1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Linux Socket Filter - Kernel level socket filtering
4 *
5 * Based on the design of the Berkeley Packet Filter. The new
6 * internal format has been designed by PLUMgrid:
7 *
8 * Copyright (c) 2011 - 2014 PLUMgrid, http://plumgrid.com
9 *
10 * Authors:
11 *
12 * Jay Schulist <jschlst@samba.org>
13 * Alexei Starovoitov <ast@plumgrid.com>
14 * Daniel Borkmann <dborkman@redhat.com>
15 *
16 * Andi Kleen - Fix a few bad bugs and races.
17 * Kris Katterjohn - Added many additional checks in bpf_check_classic()
18 */
19
20 #include <linux/atomic.h>
21 #include <linux/module.h>
22 #include <linux/types.h>
23 #include <linux/mm.h>
24 #include <linux/fcntl.h>
25 #include <linux/socket.h>
26 #include <linux/sock_diag.h>
27 #include <linux/in.h>
28 #include <linux/inet.h>
29 #include <linux/netdevice.h>
30 #include <linux/if_packet.h>
31 #include <linux/if_arp.h>
32 #include <linux/gfp.h>
33 #include <net/inet_common.h>
34 #include <net/ip.h>
35 #include <net/protocol.h>
36 #include <net/netlink.h>
37 #include <linux/skbuff.h>
38 #include <linux/skmsg.h>
39 #include <net/sock.h>
40 #include <net/flow_dissector.h>
41 #include <linux/errno.h>
42 #include <linux/timer.h>
43 #include <linux/uaccess.h>
44 #include <asm/unaligned.h>
45 #include <linux/filter.h>
46 #include <linux/ratelimit.h>
47 #include <linux/seccomp.h>
48 #include <linux/if_vlan.h>
49 #include <linux/bpf.h>
50 #include <linux/btf.h>
51 #include <net/sch_generic.h>
52 #include <net/cls_cgroup.h>
53 #include <net/dst_metadata.h>
54 #include <net/dst.h>
55 #include <net/sock_reuseport.h>
56 #include <net/busy_poll.h>
57 #include <net/tcp.h>
58 #include <net/xfrm.h>
59 #include <net/udp.h>
60 #include <linux/bpf_trace.h>
61 #include <net/xdp_sock.h>
62 #include <linux/inetdevice.h>
63 #include <net/inet_hashtables.h>
64 #include <net/inet6_hashtables.h>
65 #include <net/ip_fib.h>
66 #include <net/nexthop.h>
67 #include <net/flow.h>
68 #include <net/arp.h>
69 #include <net/ipv6.h>
70 #include <net/net_namespace.h>
71 #include <linux/seg6_local.h>
72 #include <net/seg6.h>
73 #include <net/seg6_local.h>
74 #include <net/lwtunnel.h>
75 #include <net/ipv6_stubs.h>
76 #include <net/bpf_sk_storage.h>
77 #include <net/transp_v6.h>
78 #include <linux/btf_ids.h>
79 #include <net/tls.h>
80 #include <net/xdp.h>
81
82 static const struct bpf_func_proto *
83 bpf_sk_base_func_proto(enum bpf_func_id func_id);
84
copy_bpf_fprog_from_user(struct sock_fprog * dst,sockptr_t src,int len)85 int copy_bpf_fprog_from_user(struct sock_fprog *dst, sockptr_t src, int len)
86 {
87 if (in_compat_syscall()) {
88 struct compat_sock_fprog f32;
89
90 if (len != sizeof(f32))
91 return -EINVAL;
92 if (copy_from_sockptr(&f32, src, sizeof(f32)))
93 return -EFAULT;
94 memset(dst, 0, sizeof(*dst));
95 dst->len = f32.len;
96 dst->filter = compat_ptr(f32.filter);
97 } else {
98 if (len != sizeof(*dst))
99 return -EINVAL;
100 if (copy_from_sockptr(dst, src, sizeof(*dst)))
101 return -EFAULT;
102 }
103
104 return 0;
105 }
106 EXPORT_SYMBOL_GPL(copy_bpf_fprog_from_user);
107
108 /**
109 * sk_filter_trim_cap - run a packet through a socket filter
110 * @sk: sock associated with &sk_buff
111 * @skb: buffer to filter
112 * @cap: limit on how short the eBPF program may trim the packet
113 *
114 * Run the eBPF program and then cut skb->data to correct size returned by
115 * the program. If pkt_len is 0 we toss packet. If skb->len is smaller
116 * than pkt_len we keep whole skb->data. This is the socket level
117 * wrapper to bpf_prog_run. It returns 0 if the packet should
118 * be accepted or -EPERM if the packet should be tossed.
119 *
120 */
sk_filter_trim_cap(struct sock * sk,struct sk_buff * skb,unsigned int cap)121 int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap)
122 {
123 int err;
124 struct sk_filter *filter;
125
126 /*
127 * If the skb was allocated from pfmemalloc reserves, only
128 * allow SOCK_MEMALLOC sockets to use it as this socket is
129 * helping free memory
130 */
131 if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC)) {
132 NET_INC_STATS(sock_net(sk), LINUX_MIB_PFMEMALLOCDROP);
133 return -ENOMEM;
134 }
135 err = BPF_CGROUP_RUN_PROG_INET_INGRESS(sk, skb);
136 if (err)
137 return err;
138
139 err = security_sock_rcv_skb(sk, skb);
140 if (err)
141 return err;
142
143 rcu_read_lock();
144 filter = rcu_dereference(sk->sk_filter);
145 if (filter) {
146 struct sock *save_sk = skb->sk;
147 unsigned int pkt_len;
148
149 skb->sk = sk;
150 pkt_len = bpf_prog_run_save_cb(filter->prog, skb);
151 skb->sk = save_sk;
152 err = pkt_len ? pskb_trim(skb, max(cap, pkt_len)) : -EPERM;
153 }
154 rcu_read_unlock();
155
156 return err;
157 }
158 EXPORT_SYMBOL(sk_filter_trim_cap);
159
BPF_CALL_1(bpf_skb_get_pay_offset,struct sk_buff *,skb)160 BPF_CALL_1(bpf_skb_get_pay_offset, struct sk_buff *, skb)
161 {
162 return skb_get_poff(skb);
163 }
164
BPF_CALL_3(bpf_skb_get_nlattr,struct sk_buff *,skb,u32,a,u32,x)165 BPF_CALL_3(bpf_skb_get_nlattr, struct sk_buff *, skb, u32, a, u32, x)
166 {
167 struct nlattr *nla;
168
169 if (skb_is_nonlinear(skb))
170 return 0;
171
172 if (skb->len < sizeof(struct nlattr))
173 return 0;
174
175 if (a > skb->len - sizeof(struct nlattr))
176 return 0;
177
178 nla = nla_find((struct nlattr *) &skb->data[a], skb->len - a, x);
179 if (nla)
180 return (void *) nla - (void *) skb->data;
181
182 return 0;
183 }
184
BPF_CALL_3(bpf_skb_get_nlattr_nest,struct sk_buff *,skb,u32,a,u32,x)185 BPF_CALL_3(bpf_skb_get_nlattr_nest, struct sk_buff *, skb, u32, a, u32, x)
186 {
187 struct nlattr *nla;
188
189 if (skb_is_nonlinear(skb))
190 return 0;
191
192 if (skb->len < sizeof(struct nlattr))
193 return 0;
194
195 if (a > skb->len - sizeof(struct nlattr))
196 return 0;
197
198 nla = (struct nlattr *) &skb->data[a];
199 if (nla->nla_len > skb->len - a)
200 return 0;
201
202 nla = nla_find_nested(nla, x);
203 if (nla)
204 return (void *) nla - (void *) skb->data;
205
206 return 0;
207 }
208
BPF_CALL_4(bpf_skb_load_helper_8,const struct sk_buff *,skb,const void *,data,int,headlen,int,offset)209 BPF_CALL_4(bpf_skb_load_helper_8, const struct sk_buff *, skb, const void *,
210 data, int, headlen, int, offset)
211 {
212 u8 tmp, *ptr;
213 const int len = sizeof(tmp);
214
215 if (offset >= 0) {
216 if (headlen - offset >= len)
217 return *(u8 *)(data + offset);
218 if (!skb_copy_bits(skb, offset, &tmp, sizeof(tmp)))
219 return tmp;
220 } else {
221 ptr = bpf_internal_load_pointer_neg_helper(skb, offset, len);
222 if (likely(ptr))
223 return *(u8 *)ptr;
224 }
225
226 return -EFAULT;
227 }
228
BPF_CALL_2(bpf_skb_load_helper_8_no_cache,const struct sk_buff *,skb,int,offset)229 BPF_CALL_2(bpf_skb_load_helper_8_no_cache, const struct sk_buff *, skb,
230 int, offset)
231 {
232 return ____bpf_skb_load_helper_8(skb, skb->data, skb->len - skb->data_len,
233 offset);
234 }
235
BPF_CALL_4(bpf_skb_load_helper_16,const struct sk_buff *,skb,const void *,data,int,headlen,int,offset)236 BPF_CALL_4(bpf_skb_load_helper_16, const struct sk_buff *, skb, const void *,
237 data, int, headlen, int, offset)
238 {
239 u16 tmp, *ptr;
240 const int len = sizeof(tmp);
241
242 if (offset >= 0) {
243 if (headlen - offset >= len)
244 return get_unaligned_be16(data + offset);
245 if (!skb_copy_bits(skb, offset, &tmp, sizeof(tmp)))
246 return be16_to_cpu(tmp);
247 } else {
248 ptr = bpf_internal_load_pointer_neg_helper(skb, offset, len);
249 if (likely(ptr))
250 return get_unaligned_be16(ptr);
251 }
252
253 return -EFAULT;
254 }
255
BPF_CALL_2(bpf_skb_load_helper_16_no_cache,const struct sk_buff *,skb,int,offset)256 BPF_CALL_2(bpf_skb_load_helper_16_no_cache, const struct sk_buff *, skb,
257 int, offset)
258 {
259 return ____bpf_skb_load_helper_16(skb, skb->data, skb->len - skb->data_len,
260 offset);
261 }
262
BPF_CALL_4(bpf_skb_load_helper_32,const struct sk_buff *,skb,const void *,data,int,headlen,int,offset)263 BPF_CALL_4(bpf_skb_load_helper_32, const struct sk_buff *, skb, const void *,
264 data, int, headlen, int, offset)
265 {
266 u32 tmp, *ptr;
267 const int len = sizeof(tmp);
268
269 if (likely(offset >= 0)) {
270 if (headlen - offset >= len)
271 return get_unaligned_be32(data + offset);
272 if (!skb_copy_bits(skb, offset, &tmp, sizeof(tmp)))
273 return be32_to_cpu(tmp);
274 } else {
275 ptr = bpf_internal_load_pointer_neg_helper(skb, offset, len);
276 if (likely(ptr))
277 return get_unaligned_be32(ptr);
278 }
279
280 return -EFAULT;
281 }
282
BPF_CALL_2(bpf_skb_load_helper_32_no_cache,const struct sk_buff *,skb,int,offset)283 BPF_CALL_2(bpf_skb_load_helper_32_no_cache, const struct sk_buff *, skb,
284 int, offset)
285 {
286 return ____bpf_skb_load_helper_32(skb, skb->data, skb->len - skb->data_len,
287 offset);
288 }
289
convert_skb_access(int skb_field,int dst_reg,int src_reg,struct bpf_insn * insn_buf)290 static u32 convert_skb_access(int skb_field, int dst_reg, int src_reg,
291 struct bpf_insn *insn_buf)
292 {
293 struct bpf_insn *insn = insn_buf;
294
295 switch (skb_field) {
296 case SKF_AD_MARK:
297 BUILD_BUG_ON(sizeof_field(struct sk_buff, mark) != 4);
298
299 *insn++ = BPF_LDX_MEM(BPF_W, dst_reg, src_reg,
300 offsetof(struct sk_buff, mark));
301 break;
302
303 case SKF_AD_PKTTYPE:
304 *insn++ = BPF_LDX_MEM(BPF_B, dst_reg, src_reg, PKT_TYPE_OFFSET());
305 *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, PKT_TYPE_MAX);
306 #ifdef __BIG_ENDIAN_BITFIELD
307 *insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, 5);
308 #endif
309 break;
310
311 case SKF_AD_QUEUE:
312 BUILD_BUG_ON(sizeof_field(struct sk_buff, queue_mapping) != 2);
313
314 *insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg,
315 offsetof(struct sk_buff, queue_mapping));
316 break;
317
318 case SKF_AD_VLAN_TAG:
319 BUILD_BUG_ON(sizeof_field(struct sk_buff, vlan_tci) != 2);
320
321 /* dst_reg = *(u16 *) (src_reg + offsetof(vlan_tci)) */
322 *insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg,
323 offsetof(struct sk_buff, vlan_tci));
324 break;
325 case SKF_AD_VLAN_TAG_PRESENT:
326 *insn++ = BPF_LDX_MEM(BPF_B, dst_reg, src_reg, PKT_VLAN_PRESENT_OFFSET());
327 if (PKT_VLAN_PRESENT_BIT)
328 *insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, PKT_VLAN_PRESENT_BIT);
329 if (PKT_VLAN_PRESENT_BIT < 7)
330 *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, 1);
331 break;
332 }
333
334 return insn - insn_buf;
335 }
336
convert_bpf_extensions(struct sock_filter * fp,struct bpf_insn ** insnp)337 static bool convert_bpf_extensions(struct sock_filter *fp,
338 struct bpf_insn **insnp)
339 {
340 struct bpf_insn *insn = *insnp;
341 u32 cnt;
342
343 switch (fp->k) {
344 case SKF_AD_OFF + SKF_AD_PROTOCOL:
345 BUILD_BUG_ON(sizeof_field(struct sk_buff, protocol) != 2);
346
347 /* A = *(u16 *) (CTX + offsetof(protocol)) */
348 *insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX,
349 offsetof(struct sk_buff, protocol));
350 /* A = ntohs(A) [emitting a nop or swap16] */
351 *insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16);
352 break;
353
354 case SKF_AD_OFF + SKF_AD_PKTTYPE:
355 cnt = convert_skb_access(SKF_AD_PKTTYPE, BPF_REG_A, BPF_REG_CTX, insn);
356 insn += cnt - 1;
357 break;
358
359 case SKF_AD_OFF + SKF_AD_IFINDEX:
360 case SKF_AD_OFF + SKF_AD_HATYPE:
361 BUILD_BUG_ON(sizeof_field(struct net_device, ifindex) != 4);
362 BUILD_BUG_ON(sizeof_field(struct net_device, type) != 2);
363
364 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
365 BPF_REG_TMP, BPF_REG_CTX,
366 offsetof(struct sk_buff, dev));
367 /* if (tmp != 0) goto pc + 1 */
368 *insn++ = BPF_JMP_IMM(BPF_JNE, BPF_REG_TMP, 0, 1);
369 *insn++ = BPF_EXIT_INSN();
370 if (fp->k == SKF_AD_OFF + SKF_AD_IFINDEX)
371 *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_TMP,
372 offsetof(struct net_device, ifindex));
373 else
374 *insn = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_TMP,
375 offsetof(struct net_device, type));
376 break;
377
378 case SKF_AD_OFF + SKF_AD_MARK:
379 cnt = convert_skb_access(SKF_AD_MARK, BPF_REG_A, BPF_REG_CTX, insn);
380 insn += cnt - 1;
381 break;
382
383 case SKF_AD_OFF + SKF_AD_RXHASH:
384 BUILD_BUG_ON(sizeof_field(struct sk_buff, hash) != 4);
385
386 *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX,
387 offsetof(struct sk_buff, hash));
388 break;
389
390 case SKF_AD_OFF + SKF_AD_QUEUE:
391 cnt = convert_skb_access(SKF_AD_QUEUE, BPF_REG_A, BPF_REG_CTX, insn);
392 insn += cnt - 1;
393 break;
394
395 case SKF_AD_OFF + SKF_AD_VLAN_TAG:
396 cnt = convert_skb_access(SKF_AD_VLAN_TAG,
397 BPF_REG_A, BPF_REG_CTX, insn);
398 insn += cnt - 1;
399 break;
400
401 case SKF_AD_OFF + SKF_AD_VLAN_TAG_PRESENT:
402 cnt = convert_skb_access(SKF_AD_VLAN_TAG_PRESENT,
403 BPF_REG_A, BPF_REG_CTX, insn);
404 insn += cnt - 1;
405 break;
406
407 case SKF_AD_OFF + SKF_AD_VLAN_TPID:
408 BUILD_BUG_ON(sizeof_field(struct sk_buff, vlan_proto) != 2);
409
410 /* A = *(u16 *) (CTX + offsetof(vlan_proto)) */
411 *insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX,
412 offsetof(struct sk_buff, vlan_proto));
413 /* A = ntohs(A) [emitting a nop or swap16] */
414 *insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16);
415 break;
416
417 case SKF_AD_OFF + SKF_AD_PAY_OFFSET:
418 case SKF_AD_OFF + SKF_AD_NLATTR:
419 case SKF_AD_OFF + SKF_AD_NLATTR_NEST:
420 case SKF_AD_OFF + SKF_AD_CPU:
421 case SKF_AD_OFF + SKF_AD_RANDOM:
422 /* arg1 = CTX */
423 *insn++ = BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_CTX);
424 /* arg2 = A */
425 *insn++ = BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_A);
426 /* arg3 = X */
427 *insn++ = BPF_MOV64_REG(BPF_REG_ARG3, BPF_REG_X);
428 /* Emit call(arg1=CTX, arg2=A, arg3=X) */
429 switch (fp->k) {
430 case SKF_AD_OFF + SKF_AD_PAY_OFFSET:
431 *insn = BPF_EMIT_CALL(bpf_skb_get_pay_offset);
432 break;
433 case SKF_AD_OFF + SKF_AD_NLATTR:
434 *insn = BPF_EMIT_CALL(bpf_skb_get_nlattr);
435 break;
436 case SKF_AD_OFF + SKF_AD_NLATTR_NEST:
437 *insn = BPF_EMIT_CALL(bpf_skb_get_nlattr_nest);
438 break;
439 case SKF_AD_OFF + SKF_AD_CPU:
440 *insn = BPF_EMIT_CALL(bpf_get_raw_cpu_id);
441 break;
442 case SKF_AD_OFF + SKF_AD_RANDOM:
443 *insn = BPF_EMIT_CALL(bpf_user_rnd_u32);
444 bpf_user_rnd_init_once();
445 break;
446 }
447 break;
448
449 case SKF_AD_OFF + SKF_AD_ALU_XOR_X:
450 /* A ^= X */
451 *insn = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_X);
452 break;
453
454 default:
455 /* This is just a dummy call to avoid letting the compiler
456 * evict __bpf_call_base() as an optimization. Placed here
457 * where no-one bothers.
458 */
459 BUG_ON(__bpf_call_base(0, 0, 0, 0, 0) != 0);
460 return false;
461 }
462
463 *insnp = insn;
464 return true;
465 }
466
convert_bpf_ld_abs(struct sock_filter * fp,struct bpf_insn ** insnp)467 static bool convert_bpf_ld_abs(struct sock_filter *fp, struct bpf_insn **insnp)
468 {
469 const bool unaligned_ok = IS_BUILTIN(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS);
470 int size = bpf_size_to_bytes(BPF_SIZE(fp->code));
471 bool endian = BPF_SIZE(fp->code) == BPF_H ||
472 BPF_SIZE(fp->code) == BPF_W;
473 bool indirect = BPF_MODE(fp->code) == BPF_IND;
474 const int ip_align = NET_IP_ALIGN;
475 struct bpf_insn *insn = *insnp;
476 int offset = fp->k;
477
478 if (!indirect &&
479 ((unaligned_ok && offset >= 0) ||
480 (!unaligned_ok && offset >= 0 &&
481 offset + ip_align >= 0 &&
482 offset + ip_align % size == 0))) {
483 bool ldx_off_ok = offset <= S16_MAX;
484
485 *insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_H);
486 if (offset)
487 *insn++ = BPF_ALU64_IMM(BPF_SUB, BPF_REG_TMP, offset);
488 *insn++ = BPF_JMP_IMM(BPF_JSLT, BPF_REG_TMP,
489 size, 2 + endian + (!ldx_off_ok * 2));
490 if (ldx_off_ok) {
491 *insn++ = BPF_LDX_MEM(BPF_SIZE(fp->code), BPF_REG_A,
492 BPF_REG_D, offset);
493 } else {
494 *insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_D);
495 *insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_TMP, offset);
496 *insn++ = BPF_LDX_MEM(BPF_SIZE(fp->code), BPF_REG_A,
497 BPF_REG_TMP, 0);
498 }
499 if (endian)
500 *insn++ = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, size * 8);
501 *insn++ = BPF_JMP_A(8);
502 }
503
504 *insn++ = BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_CTX);
505 *insn++ = BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_D);
506 *insn++ = BPF_MOV64_REG(BPF_REG_ARG3, BPF_REG_H);
507 if (!indirect) {
508 *insn++ = BPF_MOV64_IMM(BPF_REG_ARG4, offset);
509 } else {
510 *insn++ = BPF_MOV64_REG(BPF_REG_ARG4, BPF_REG_X);
511 if (fp->k)
512 *insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_ARG4, offset);
513 }
514
515 switch (BPF_SIZE(fp->code)) {
516 case BPF_B:
517 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_8);
518 break;
519 case BPF_H:
520 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_16);
521 break;
522 case BPF_W:
523 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_32);
524 break;
525 default:
526 return false;
527 }
528
529 *insn++ = BPF_JMP_IMM(BPF_JSGE, BPF_REG_A, 0, 2);
530 *insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A);
531 *insn = BPF_EXIT_INSN();
532
533 *insnp = insn;
534 return true;
535 }
536
537 /**
538 * bpf_convert_filter - convert filter program
539 * @prog: the user passed filter program
540 * @len: the length of the user passed filter program
541 * @new_prog: allocated 'struct bpf_prog' or NULL
542 * @new_len: pointer to store length of converted program
543 * @seen_ld_abs: bool whether we've seen ld_abs/ind
544 *
545 * Remap 'sock_filter' style classic BPF (cBPF) instruction set to 'bpf_insn'
546 * style extended BPF (eBPF).
547 * Conversion workflow:
548 *
549 * 1) First pass for calculating the new program length:
550 * bpf_convert_filter(old_prog, old_len, NULL, &new_len, &seen_ld_abs)
551 *
552 * 2) 2nd pass to remap in two passes: 1st pass finds new
553 * jump offsets, 2nd pass remapping:
554 * bpf_convert_filter(old_prog, old_len, new_prog, &new_len, &seen_ld_abs)
555 */
bpf_convert_filter(struct sock_filter * prog,int len,struct bpf_prog * new_prog,int * new_len,bool * seen_ld_abs)556 static int bpf_convert_filter(struct sock_filter *prog, int len,
557 struct bpf_prog *new_prog, int *new_len,
558 bool *seen_ld_abs)
559 {
560 int new_flen = 0, pass = 0, target, i, stack_off;
561 struct bpf_insn *new_insn, *first_insn = NULL;
562 struct sock_filter *fp;
563 int *addrs = NULL;
564 u8 bpf_src;
565
566 BUILD_BUG_ON(BPF_MEMWORDS * sizeof(u32) > MAX_BPF_STACK);
567 BUILD_BUG_ON(BPF_REG_FP + 1 != MAX_BPF_REG);
568
569 if (len <= 0 || len > BPF_MAXINSNS)
570 return -EINVAL;
571
572 if (new_prog) {
573 first_insn = new_prog->insnsi;
574 addrs = kcalloc(len, sizeof(*addrs),
575 GFP_KERNEL | __GFP_NOWARN);
576 if (!addrs)
577 return -ENOMEM;
578 }
579
580 do_pass:
581 new_insn = first_insn;
582 fp = prog;
583
584 /* Classic BPF related prologue emission. */
585 if (new_prog) {
586 /* Classic BPF expects A and X to be reset first. These need
587 * to be guaranteed to be the first two instructions.
588 */
589 *new_insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A);
590 *new_insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_X, BPF_REG_X);
591
592 /* All programs must keep CTX in callee saved BPF_REG_CTX.
593 * In eBPF case it's done by the compiler, here we need to
594 * do this ourself. Initial CTX is present in BPF_REG_ARG1.
595 */
596 *new_insn++ = BPF_MOV64_REG(BPF_REG_CTX, BPF_REG_ARG1);
597 if (*seen_ld_abs) {
598 /* For packet access in classic BPF, cache skb->data
599 * in callee-saved BPF R8 and skb->len - skb->data_len
600 * (headlen) in BPF R9. Since classic BPF is read-only
601 * on CTX, we only need to cache it once.
602 */
603 *new_insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
604 BPF_REG_D, BPF_REG_CTX,
605 offsetof(struct sk_buff, data));
606 *new_insn++ = BPF_LDX_MEM(BPF_W, BPF_REG_H, BPF_REG_CTX,
607 offsetof(struct sk_buff, len));
608 *new_insn++ = BPF_LDX_MEM(BPF_W, BPF_REG_TMP, BPF_REG_CTX,
609 offsetof(struct sk_buff, data_len));
610 *new_insn++ = BPF_ALU32_REG(BPF_SUB, BPF_REG_H, BPF_REG_TMP);
611 }
612 } else {
613 new_insn += 3;
614 }
615
616 for (i = 0; i < len; fp++, i++) {
617 struct bpf_insn tmp_insns[32] = { };
618 struct bpf_insn *insn = tmp_insns;
619
620 if (addrs)
621 addrs[i] = new_insn - first_insn;
622
623 switch (fp->code) {
624 /* All arithmetic insns and skb loads map as-is. */
625 case BPF_ALU | BPF_ADD | BPF_X:
626 case BPF_ALU | BPF_ADD | BPF_K:
627 case BPF_ALU | BPF_SUB | BPF_X:
628 case BPF_ALU | BPF_SUB | BPF_K:
629 case BPF_ALU | BPF_AND | BPF_X:
630 case BPF_ALU | BPF_AND | BPF_K:
631 case BPF_ALU | BPF_OR | BPF_X:
632 case BPF_ALU | BPF_OR | BPF_K:
633 case BPF_ALU | BPF_LSH | BPF_X:
634 case BPF_ALU | BPF_LSH | BPF_K:
635 case BPF_ALU | BPF_RSH | BPF_X:
636 case BPF_ALU | BPF_RSH | BPF_K:
637 case BPF_ALU | BPF_XOR | BPF_X:
638 case BPF_ALU | BPF_XOR | BPF_K:
639 case BPF_ALU | BPF_MUL | BPF_X:
640 case BPF_ALU | BPF_MUL | BPF_K:
641 case BPF_ALU | BPF_DIV | BPF_X:
642 case BPF_ALU | BPF_DIV | BPF_K:
643 case BPF_ALU | BPF_MOD | BPF_X:
644 case BPF_ALU | BPF_MOD | BPF_K:
645 case BPF_ALU | BPF_NEG:
646 case BPF_LD | BPF_ABS | BPF_W:
647 case BPF_LD | BPF_ABS | BPF_H:
648 case BPF_LD | BPF_ABS | BPF_B:
649 case BPF_LD | BPF_IND | BPF_W:
650 case BPF_LD | BPF_IND | BPF_H:
651 case BPF_LD | BPF_IND | BPF_B:
652 /* Check for overloaded BPF extension and
653 * directly convert it if found, otherwise
654 * just move on with mapping.
655 */
656 if (BPF_CLASS(fp->code) == BPF_LD &&
657 BPF_MODE(fp->code) == BPF_ABS &&
658 convert_bpf_extensions(fp, &insn))
659 break;
660 if (BPF_CLASS(fp->code) == BPF_LD &&
661 convert_bpf_ld_abs(fp, &insn)) {
662 *seen_ld_abs = true;
663 break;
664 }
665
666 if (fp->code == (BPF_ALU | BPF_DIV | BPF_X) ||
667 fp->code == (BPF_ALU | BPF_MOD | BPF_X)) {
668 *insn++ = BPF_MOV32_REG(BPF_REG_X, BPF_REG_X);
669 /* Error with exception code on div/mod by 0.
670 * For cBPF programs, this was always return 0.
671 */
672 *insn++ = BPF_JMP_IMM(BPF_JNE, BPF_REG_X, 0, 2);
673 *insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A);
674 *insn++ = BPF_EXIT_INSN();
675 }
676
677 *insn = BPF_RAW_INSN(fp->code, BPF_REG_A, BPF_REG_X, 0, fp->k);
678 break;
679
680 /* Jump transformation cannot use BPF block macros
681 * everywhere as offset calculation and target updates
682 * require a bit more work than the rest, i.e. jump
683 * opcodes map as-is, but offsets need adjustment.
684 */
685
686 #define BPF_EMIT_JMP \
687 do { \
688 const s32 off_min = S16_MIN, off_max = S16_MAX; \
689 s32 off; \
690 \
691 if (target >= len || target < 0) \
692 goto err; \
693 off = addrs ? addrs[target] - addrs[i] - 1 : 0; \
694 /* Adjust pc relative offset for 2nd or 3rd insn. */ \
695 off -= insn - tmp_insns; \
696 /* Reject anything not fitting into insn->off. */ \
697 if (off < off_min || off > off_max) \
698 goto err; \
699 insn->off = off; \
700 } while (0)
701
702 case BPF_JMP | BPF_JA:
703 target = i + fp->k + 1;
704 insn->code = fp->code;
705 BPF_EMIT_JMP;
706 break;
707
708 case BPF_JMP | BPF_JEQ | BPF_K:
709 case BPF_JMP | BPF_JEQ | BPF_X:
710 case BPF_JMP | BPF_JSET | BPF_K:
711 case BPF_JMP | BPF_JSET | BPF_X:
712 case BPF_JMP | BPF_JGT | BPF_K:
713 case BPF_JMP | BPF_JGT | BPF_X:
714 case BPF_JMP | BPF_JGE | BPF_K:
715 case BPF_JMP | BPF_JGE | BPF_X:
716 if (BPF_SRC(fp->code) == BPF_K && (int) fp->k < 0) {
717 /* BPF immediates are signed, zero extend
718 * immediate into tmp register and use it
719 * in compare insn.
720 */
721 *insn++ = BPF_MOV32_IMM(BPF_REG_TMP, fp->k);
722
723 insn->dst_reg = BPF_REG_A;
724 insn->src_reg = BPF_REG_TMP;
725 bpf_src = BPF_X;
726 } else {
727 insn->dst_reg = BPF_REG_A;
728 insn->imm = fp->k;
729 bpf_src = BPF_SRC(fp->code);
730 insn->src_reg = bpf_src == BPF_X ? BPF_REG_X : 0;
731 }
732
733 /* Common case where 'jump_false' is next insn. */
734 if (fp->jf == 0) {
735 insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src;
736 target = i + fp->jt + 1;
737 BPF_EMIT_JMP;
738 break;
739 }
740
741 /* Convert some jumps when 'jump_true' is next insn. */
742 if (fp->jt == 0) {
743 switch (BPF_OP(fp->code)) {
744 case BPF_JEQ:
745 insn->code = BPF_JMP | BPF_JNE | bpf_src;
746 break;
747 case BPF_JGT:
748 insn->code = BPF_JMP | BPF_JLE | bpf_src;
749 break;
750 case BPF_JGE:
751 insn->code = BPF_JMP | BPF_JLT | bpf_src;
752 break;
753 default:
754 goto jmp_rest;
755 }
756
757 target = i + fp->jf + 1;
758 BPF_EMIT_JMP;
759 break;
760 }
761 jmp_rest:
762 /* Other jumps are mapped into two insns: Jxx and JA. */
763 target = i + fp->jt + 1;
764 insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src;
765 BPF_EMIT_JMP;
766 insn++;
767
768 insn->code = BPF_JMP | BPF_JA;
769 target = i + fp->jf + 1;
770 BPF_EMIT_JMP;
771 break;
772
773 /* ldxb 4 * ([14] & 0xf) is remaped into 6 insns. */
774 case BPF_LDX | BPF_MSH | BPF_B: {
775 struct sock_filter tmp = {
776 .code = BPF_LD | BPF_ABS | BPF_B,
777 .k = fp->k,
778 };
779
780 *seen_ld_abs = true;
781
782 /* X = A */
783 *insn++ = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
784 /* A = BPF_R0 = *(u8 *) (skb->data + K) */
785 convert_bpf_ld_abs(&tmp, &insn);
786 insn++;
787 /* A &= 0xf */
788 *insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_A, 0xf);
789 /* A <<= 2 */
790 *insn++ = BPF_ALU32_IMM(BPF_LSH, BPF_REG_A, 2);
791 /* tmp = X */
792 *insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_X);
793 /* X = A */
794 *insn++ = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
795 /* A = tmp */
796 *insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_TMP);
797 break;
798 }
799 /* RET_K is remaped into 2 insns. RET_A case doesn't need an
800 * extra mov as BPF_REG_0 is already mapped into BPF_REG_A.
801 */
802 case BPF_RET | BPF_A:
803 case BPF_RET | BPF_K:
804 if (BPF_RVAL(fp->code) == BPF_K)
805 *insn++ = BPF_MOV32_RAW(BPF_K, BPF_REG_0,
806 0, fp->k);
807 *insn = BPF_EXIT_INSN();
808 break;
809
810 /* Store to stack. */
811 case BPF_ST:
812 case BPF_STX:
813 stack_off = fp->k * 4 + 4;
814 *insn = BPF_STX_MEM(BPF_W, BPF_REG_FP, BPF_CLASS(fp->code) ==
815 BPF_ST ? BPF_REG_A : BPF_REG_X,
816 -stack_off);
817 /* check_load_and_stores() verifies that classic BPF can
818 * load from stack only after write, so tracking
819 * stack_depth for ST|STX insns is enough
820 */
821 if (new_prog && new_prog->aux->stack_depth < stack_off)
822 new_prog->aux->stack_depth = stack_off;
823 break;
824
825 /* Load from stack. */
826 case BPF_LD | BPF_MEM:
827 case BPF_LDX | BPF_MEM:
828 stack_off = fp->k * 4 + 4;
829 *insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD ?
830 BPF_REG_A : BPF_REG_X, BPF_REG_FP,
831 -stack_off);
832 break;
833
834 /* A = K or X = K */
835 case BPF_LD | BPF_IMM:
836 case BPF_LDX | BPF_IMM:
837 *insn = BPF_MOV32_IMM(BPF_CLASS(fp->code) == BPF_LD ?
838 BPF_REG_A : BPF_REG_X, fp->k);
839 break;
840
841 /* X = A */
842 case BPF_MISC | BPF_TAX:
843 *insn = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
844 break;
845
846 /* A = X */
847 case BPF_MISC | BPF_TXA:
848 *insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_X);
849 break;
850
851 /* A = skb->len or X = skb->len */
852 case BPF_LD | BPF_W | BPF_LEN:
853 case BPF_LDX | BPF_W | BPF_LEN:
854 *insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD ?
855 BPF_REG_A : BPF_REG_X, BPF_REG_CTX,
856 offsetof(struct sk_buff, len));
857 break;
858
859 /* Access seccomp_data fields. */
860 case BPF_LDX | BPF_ABS | BPF_W:
861 /* A = *(u32 *) (ctx + K) */
862 *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX, fp->k);
863 break;
864
865 /* Unknown instruction. */
866 default:
867 goto err;
868 }
869
870 insn++;
871 if (new_prog)
872 memcpy(new_insn, tmp_insns,
873 sizeof(*insn) * (insn - tmp_insns));
874 new_insn += insn - tmp_insns;
875 }
876
877 if (!new_prog) {
878 /* Only calculating new length. */
879 *new_len = new_insn - first_insn;
880 if (*seen_ld_abs)
881 *new_len += 4; /* Prologue bits. */
882 return 0;
883 }
884
885 pass++;
886 if (new_flen != new_insn - first_insn) {
887 new_flen = new_insn - first_insn;
888 if (pass > 2)
889 goto err;
890 goto do_pass;
891 }
892
893 kfree(addrs);
894 BUG_ON(*new_len != new_flen);
895 return 0;
896 err:
897 kfree(addrs);
898 return -EINVAL;
899 }
900
901 /* Security:
902 *
903 * As we dont want to clear mem[] array for each packet going through
904 * __bpf_prog_run(), we check that filter loaded by user never try to read
905 * a cell if not previously written, and we check all branches to be sure
906 * a malicious user doesn't try to abuse us.
907 */
check_load_and_stores(const struct sock_filter * filter,int flen)908 static int check_load_and_stores(const struct sock_filter *filter, int flen)
909 {
910 u16 *masks, memvalid = 0; /* One bit per cell, 16 cells */
911 int pc, ret = 0;
912
913 BUILD_BUG_ON(BPF_MEMWORDS > 16);
914
915 masks = kmalloc_array(flen, sizeof(*masks), GFP_KERNEL);
916 if (!masks)
917 return -ENOMEM;
918
919 memset(masks, 0xff, flen * sizeof(*masks));
920
921 for (pc = 0; pc < flen; pc++) {
922 memvalid &= masks[pc];
923
924 switch (filter[pc].code) {
925 case BPF_ST:
926 case BPF_STX:
927 memvalid |= (1 << filter[pc].k);
928 break;
929 case BPF_LD | BPF_MEM:
930 case BPF_LDX | BPF_MEM:
931 if (!(memvalid & (1 << filter[pc].k))) {
932 ret = -EINVAL;
933 goto error;
934 }
935 break;
936 case BPF_JMP | BPF_JA:
937 /* A jump must set masks on target */
938 masks[pc + 1 + filter[pc].k] &= memvalid;
939 memvalid = ~0;
940 break;
941 case BPF_JMP | BPF_JEQ | BPF_K:
942 case BPF_JMP | BPF_JEQ | BPF_X:
943 case BPF_JMP | BPF_JGE | BPF_K:
944 case BPF_JMP | BPF_JGE | BPF_X:
945 case BPF_JMP | BPF_JGT | BPF_K:
946 case BPF_JMP | BPF_JGT | BPF_X:
947 case BPF_JMP | BPF_JSET | BPF_K:
948 case BPF_JMP | BPF_JSET | BPF_X:
949 /* A jump must set masks on targets */
950 masks[pc + 1 + filter[pc].jt] &= memvalid;
951 masks[pc + 1 + filter[pc].jf] &= memvalid;
952 memvalid = ~0;
953 break;
954 }
955 }
956 error:
957 kfree(masks);
958 return ret;
959 }
960
chk_code_allowed(u16 code_to_probe)961 static bool chk_code_allowed(u16 code_to_probe)
962 {
963 static const bool codes[] = {
964 /* 32 bit ALU operations */
965 [BPF_ALU | BPF_ADD | BPF_K] = true,
966 [BPF_ALU | BPF_ADD | BPF_X] = true,
967 [BPF_ALU | BPF_SUB | BPF_K] = true,
968 [BPF_ALU | BPF_SUB | BPF_X] = true,
969 [BPF_ALU | BPF_MUL | BPF_K] = true,
970 [BPF_ALU | BPF_MUL | BPF_X] = true,
971 [BPF_ALU | BPF_DIV | BPF_K] = true,
972 [BPF_ALU | BPF_DIV | BPF_X] = true,
973 [BPF_ALU | BPF_MOD | BPF_K] = true,
974 [BPF_ALU | BPF_MOD | BPF_X] = true,
975 [BPF_ALU | BPF_AND | BPF_K] = true,
976 [BPF_ALU | BPF_AND | BPF_X] = true,
977 [BPF_ALU | BPF_OR | BPF_K] = true,
978 [BPF_ALU | BPF_OR | BPF_X] = true,
979 [BPF_ALU | BPF_XOR | BPF_K] = true,
980 [BPF_ALU | BPF_XOR | BPF_X] = true,
981 [BPF_ALU | BPF_LSH | BPF_K] = true,
982 [BPF_ALU | BPF_LSH | BPF_X] = true,
983 [BPF_ALU | BPF_RSH | BPF_K] = true,
984 [BPF_ALU | BPF_RSH | BPF_X] = true,
985 [BPF_ALU | BPF_NEG] = true,
986 /* Load instructions */
987 [BPF_LD | BPF_W | BPF_ABS] = true,
988 [BPF_LD | BPF_H | BPF_ABS] = true,
989 [BPF_LD | BPF_B | BPF_ABS] = true,
990 [BPF_LD | BPF_W | BPF_LEN] = true,
991 [BPF_LD | BPF_W | BPF_IND] = true,
992 [BPF_LD | BPF_H | BPF_IND] = true,
993 [BPF_LD | BPF_B | BPF_IND] = true,
994 [BPF_LD | BPF_IMM] = true,
995 [BPF_LD | BPF_MEM] = true,
996 [BPF_LDX | BPF_W | BPF_LEN] = true,
997 [BPF_LDX | BPF_B | BPF_MSH] = true,
998 [BPF_LDX | BPF_IMM] = true,
999 [BPF_LDX | BPF_MEM] = true,
1000 /* Store instructions */
1001 [BPF_ST] = true,
1002 [BPF_STX] = true,
1003 /* Misc instructions */
1004 [BPF_MISC | BPF_TAX] = true,
1005 [BPF_MISC | BPF_TXA] = true,
1006 /* Return instructions */
1007 [BPF_RET | BPF_K] = true,
1008 [BPF_RET | BPF_A] = true,
1009 /* Jump instructions */
1010 [BPF_JMP | BPF_JA] = true,
1011 [BPF_JMP | BPF_JEQ | BPF_K] = true,
1012 [BPF_JMP | BPF_JEQ | BPF_X] = true,
1013 [BPF_JMP | BPF_JGE | BPF_K] = true,
1014 [BPF_JMP | BPF_JGE | BPF_X] = true,
1015 [BPF_JMP | BPF_JGT | BPF_K] = true,
1016 [BPF_JMP | BPF_JGT | BPF_X] = true,
1017 [BPF_JMP | BPF_JSET | BPF_K] = true,
1018 [BPF_JMP | BPF_JSET | BPF_X] = true,
1019 };
1020
1021 if (code_to_probe >= ARRAY_SIZE(codes))
1022 return false;
1023
1024 return codes[code_to_probe];
1025 }
1026
bpf_check_basics_ok(const struct sock_filter * filter,unsigned int flen)1027 static bool bpf_check_basics_ok(const struct sock_filter *filter,
1028 unsigned int flen)
1029 {
1030 if (filter == NULL)
1031 return false;
1032 if (flen == 0 || flen > BPF_MAXINSNS)
1033 return false;
1034
1035 return true;
1036 }
1037
1038 /**
1039 * bpf_check_classic - verify socket filter code
1040 * @filter: filter to verify
1041 * @flen: length of filter
1042 *
1043 * Check the user's filter code. If we let some ugly
1044 * filter code slip through kaboom! The filter must contain
1045 * no references or jumps that are out of range, no illegal
1046 * instructions, and must end with a RET instruction.
1047 *
1048 * All jumps are forward as they are not signed.
1049 *
1050 * Returns 0 if the rule set is legal or -EINVAL if not.
1051 */
bpf_check_classic(const struct sock_filter * filter,unsigned int flen)1052 static int bpf_check_classic(const struct sock_filter *filter,
1053 unsigned int flen)
1054 {
1055 bool anc_found;
1056 int pc;
1057
1058 /* Check the filter code now */
1059 for (pc = 0; pc < flen; pc++) {
1060 const struct sock_filter *ftest = &filter[pc];
1061
1062 /* May we actually operate on this code? */
1063 if (!chk_code_allowed(ftest->code))
1064 return -EINVAL;
1065
1066 /* Some instructions need special checks */
1067 switch (ftest->code) {
1068 case BPF_ALU | BPF_DIV | BPF_K:
1069 case BPF_ALU | BPF_MOD | BPF_K:
1070 /* Check for division by zero */
1071 if (ftest->k == 0)
1072 return -EINVAL;
1073 break;
1074 case BPF_ALU | BPF_LSH | BPF_K:
1075 case BPF_ALU | BPF_RSH | BPF_K:
1076 if (ftest->k >= 32)
1077 return -EINVAL;
1078 break;
1079 case BPF_LD | BPF_MEM:
1080 case BPF_LDX | BPF_MEM:
1081 case BPF_ST:
1082 case BPF_STX:
1083 /* Check for invalid memory addresses */
1084 if (ftest->k >= BPF_MEMWORDS)
1085 return -EINVAL;
1086 break;
1087 case BPF_JMP | BPF_JA:
1088 /* Note, the large ftest->k might cause loops.
1089 * Compare this with conditional jumps below,
1090 * where offsets are limited. --ANK (981016)
1091 */
1092 if (ftest->k >= (unsigned int)(flen - pc - 1))
1093 return -EINVAL;
1094 break;
1095 case BPF_JMP | BPF_JEQ | BPF_K:
1096 case BPF_JMP | BPF_JEQ | BPF_X:
1097 case BPF_JMP | BPF_JGE | BPF_K:
1098 case BPF_JMP | BPF_JGE | BPF_X:
1099 case BPF_JMP | BPF_JGT | BPF_K:
1100 case BPF_JMP | BPF_JGT | BPF_X:
1101 case BPF_JMP | BPF_JSET | BPF_K:
1102 case BPF_JMP | BPF_JSET | BPF_X:
1103 /* Both conditionals must be safe */
1104 if (pc + ftest->jt + 1 >= flen ||
1105 pc + ftest->jf + 1 >= flen)
1106 return -EINVAL;
1107 break;
1108 case BPF_LD | BPF_W | BPF_ABS:
1109 case BPF_LD | BPF_H | BPF_ABS:
1110 case BPF_LD | BPF_B | BPF_ABS:
1111 anc_found = false;
1112 if (bpf_anc_helper(ftest) & BPF_ANC)
1113 anc_found = true;
1114 /* Ancillary operation unknown or unsupported */
1115 if (anc_found == false && ftest->k >= SKF_AD_OFF)
1116 return -EINVAL;
1117 }
1118 }
1119
1120 /* Last instruction must be a RET code */
1121 switch (filter[flen - 1].code) {
1122 case BPF_RET | BPF_K:
1123 case BPF_RET | BPF_A:
1124 return check_load_and_stores(filter, flen);
1125 }
1126
1127 return -EINVAL;
1128 }
1129
bpf_prog_store_orig_filter(struct bpf_prog * fp,const struct sock_fprog * fprog)1130 static int bpf_prog_store_orig_filter(struct bpf_prog *fp,
1131 const struct sock_fprog *fprog)
1132 {
1133 unsigned int fsize = bpf_classic_proglen(fprog);
1134 struct sock_fprog_kern *fkprog;
1135
1136 fp->orig_prog = kmalloc(sizeof(*fkprog), GFP_KERNEL);
1137 if (!fp->orig_prog)
1138 return -ENOMEM;
1139
1140 fkprog = fp->orig_prog;
1141 fkprog->len = fprog->len;
1142
1143 fkprog->filter = kmemdup(fp->insns, fsize,
1144 GFP_KERNEL | __GFP_NOWARN);
1145 if (!fkprog->filter) {
1146 kfree(fp->orig_prog);
1147 return -ENOMEM;
1148 }
1149
1150 return 0;
1151 }
1152
bpf_release_orig_filter(struct bpf_prog * fp)1153 static void bpf_release_orig_filter(struct bpf_prog *fp)
1154 {
1155 struct sock_fprog_kern *fprog = fp->orig_prog;
1156
1157 if (fprog) {
1158 kfree(fprog->filter);
1159 kfree(fprog);
1160 }
1161 }
1162
__bpf_prog_release(struct bpf_prog * prog)1163 static void __bpf_prog_release(struct bpf_prog *prog)
1164 {
1165 if (prog->type == BPF_PROG_TYPE_SOCKET_FILTER) {
1166 bpf_prog_put(prog);
1167 } else {
1168 bpf_release_orig_filter(prog);
1169 bpf_prog_free(prog);
1170 }
1171 }
1172
__sk_filter_release(struct sk_filter * fp)1173 static void __sk_filter_release(struct sk_filter *fp)
1174 {
1175 __bpf_prog_release(fp->prog);
1176 kfree(fp);
1177 }
1178
1179 /**
1180 * sk_filter_release_rcu - Release a socket filter by rcu_head
1181 * @rcu: rcu_head that contains the sk_filter to free
1182 */
sk_filter_release_rcu(struct rcu_head * rcu)1183 static void sk_filter_release_rcu(struct rcu_head *rcu)
1184 {
1185 struct sk_filter *fp = container_of(rcu, struct sk_filter, rcu);
1186
1187 __sk_filter_release(fp);
1188 }
1189
1190 /**
1191 * sk_filter_release - release a socket filter
1192 * @fp: filter to remove
1193 *
1194 * Remove a filter from a socket and release its resources.
1195 */
sk_filter_release(struct sk_filter * fp)1196 static void sk_filter_release(struct sk_filter *fp)
1197 {
1198 if (refcount_dec_and_test(&fp->refcnt))
1199 call_rcu(&fp->rcu, sk_filter_release_rcu);
1200 }
1201
sk_filter_uncharge(struct sock * sk,struct sk_filter * fp)1202 void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp)
1203 {
1204 u32 filter_size = bpf_prog_size(fp->prog->len);
1205
1206 atomic_sub(filter_size, &sk->sk_omem_alloc);
1207 sk_filter_release(fp);
1208 }
1209
1210 /* try to charge the socket memory if there is space available
1211 * return true on success
1212 */
__sk_filter_charge(struct sock * sk,struct sk_filter * fp)1213 static bool __sk_filter_charge(struct sock *sk, struct sk_filter *fp)
1214 {
1215 u32 filter_size = bpf_prog_size(fp->prog->len);
1216
1217 /* same check as in sock_kmalloc() */
1218 if (filter_size <= sysctl_optmem_max &&
1219 atomic_read(&sk->sk_omem_alloc) + filter_size < sysctl_optmem_max) {
1220 atomic_add(filter_size, &sk->sk_omem_alloc);
1221 return true;
1222 }
1223 return false;
1224 }
1225
sk_filter_charge(struct sock * sk,struct sk_filter * fp)1226 bool sk_filter_charge(struct sock *sk, struct sk_filter *fp)
1227 {
1228 if (!refcount_inc_not_zero(&fp->refcnt))
1229 return false;
1230
1231 if (!__sk_filter_charge(sk, fp)) {
1232 sk_filter_release(fp);
1233 return false;
1234 }
1235 return true;
1236 }
1237
bpf_migrate_filter(struct bpf_prog * fp)1238 static struct bpf_prog *bpf_migrate_filter(struct bpf_prog *fp)
1239 {
1240 struct sock_filter *old_prog;
1241 struct bpf_prog *old_fp;
1242 int err, new_len, old_len = fp->len;
1243 bool seen_ld_abs = false;
1244
1245 /* We are free to overwrite insns et al right here as it
1246 * won't be used at this point in time anymore internally
1247 * after the migration to the internal BPF instruction
1248 * representation.
1249 */
1250 BUILD_BUG_ON(sizeof(struct sock_filter) !=
1251 sizeof(struct bpf_insn));
1252
1253 /* Conversion cannot happen on overlapping memory areas,
1254 * so we need to keep the user BPF around until the 2nd
1255 * pass. At this time, the user BPF is stored in fp->insns.
1256 */
1257 old_prog = kmemdup(fp->insns, old_len * sizeof(struct sock_filter),
1258 GFP_KERNEL | __GFP_NOWARN);
1259 if (!old_prog) {
1260 err = -ENOMEM;
1261 goto out_err;
1262 }
1263
1264 /* 1st pass: calculate the new program length. */
1265 err = bpf_convert_filter(old_prog, old_len, NULL, &new_len,
1266 &seen_ld_abs);
1267 if (err)
1268 goto out_err_free;
1269
1270 /* Expand fp for appending the new filter representation. */
1271 old_fp = fp;
1272 fp = bpf_prog_realloc(old_fp, bpf_prog_size(new_len), 0);
1273 if (!fp) {
1274 /* The old_fp is still around in case we couldn't
1275 * allocate new memory, so uncharge on that one.
1276 */
1277 fp = old_fp;
1278 err = -ENOMEM;
1279 goto out_err_free;
1280 }
1281
1282 fp->len = new_len;
1283
1284 /* 2nd pass: remap sock_filter insns into bpf_insn insns. */
1285 err = bpf_convert_filter(old_prog, old_len, fp, &new_len,
1286 &seen_ld_abs);
1287 if (err)
1288 /* 2nd bpf_convert_filter() can fail only if it fails
1289 * to allocate memory, remapping must succeed. Note,
1290 * that at this time old_fp has already been released
1291 * by krealloc().
1292 */
1293 goto out_err_free;
1294
1295 fp = bpf_prog_select_runtime(fp, &err);
1296 if (err)
1297 goto out_err_free;
1298
1299 kfree(old_prog);
1300 return fp;
1301
1302 out_err_free:
1303 kfree(old_prog);
1304 out_err:
1305 __bpf_prog_release(fp);
1306 return ERR_PTR(err);
1307 }
1308
bpf_prepare_filter(struct bpf_prog * fp,bpf_aux_classic_check_t trans)1309 static struct bpf_prog *bpf_prepare_filter(struct bpf_prog *fp,
1310 bpf_aux_classic_check_t trans)
1311 {
1312 int err;
1313
1314 fp->bpf_func = NULL;
1315 fp->jited = 0;
1316
1317 err = bpf_check_classic(fp->insns, fp->len);
1318 if (err) {
1319 __bpf_prog_release(fp);
1320 return ERR_PTR(err);
1321 }
1322
1323 /* There might be additional checks and transformations
1324 * needed on classic filters, f.e. in case of seccomp.
1325 */
1326 if (trans) {
1327 err = trans(fp->insns, fp->len);
1328 if (err) {
1329 __bpf_prog_release(fp);
1330 return ERR_PTR(err);
1331 }
1332 }
1333
1334 /* Probe if we can JIT compile the filter and if so, do
1335 * the compilation of the filter.
1336 */
1337 bpf_jit_compile(fp);
1338
1339 /* JIT compiler couldn't process this filter, so do the
1340 * internal BPF translation for the optimized interpreter.
1341 */
1342 if (!fp->jited)
1343 fp = bpf_migrate_filter(fp);
1344
1345 return fp;
1346 }
1347
1348 /**
1349 * bpf_prog_create - create an unattached filter
1350 * @pfp: the unattached filter that is created
1351 * @fprog: the filter program
1352 *
1353 * Create a filter independent of any socket. We first run some
1354 * sanity checks on it to make sure it does not explode on us later.
1355 * If an error occurs or there is insufficient memory for the filter
1356 * a negative errno code is returned. On success the return is zero.
1357 */
bpf_prog_create(struct bpf_prog ** pfp,struct sock_fprog_kern * fprog)1358 int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog)
1359 {
1360 unsigned int fsize = bpf_classic_proglen(fprog);
1361 struct bpf_prog *fp;
1362
1363 /* Make sure new filter is there and in the right amounts. */
1364 if (!bpf_check_basics_ok(fprog->filter, fprog->len))
1365 return -EINVAL;
1366
1367 fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
1368 if (!fp)
1369 return -ENOMEM;
1370
1371 memcpy(fp->insns, fprog->filter, fsize);
1372
1373 fp->len = fprog->len;
1374 /* Since unattached filters are not copied back to user
1375 * space through sk_get_filter(), we do not need to hold
1376 * a copy here, and can spare us the work.
1377 */
1378 fp->orig_prog = NULL;
1379
1380 /* bpf_prepare_filter() already takes care of freeing
1381 * memory in case something goes wrong.
1382 */
1383 fp = bpf_prepare_filter(fp, NULL);
1384 if (IS_ERR(fp))
1385 return PTR_ERR(fp);
1386
1387 *pfp = fp;
1388 return 0;
1389 }
1390 EXPORT_SYMBOL_GPL(bpf_prog_create);
1391
1392 /**
1393 * bpf_prog_create_from_user - create an unattached filter from user buffer
1394 * @pfp: the unattached filter that is created
1395 * @fprog: the filter program
1396 * @trans: post-classic verifier transformation handler
1397 * @save_orig: save classic BPF program
1398 *
1399 * This function effectively does the same as bpf_prog_create(), only
1400 * that it builds up its insns buffer from user space provided buffer.
1401 * It also allows for passing a bpf_aux_classic_check_t handler.
1402 */
bpf_prog_create_from_user(struct bpf_prog ** pfp,struct sock_fprog * fprog,bpf_aux_classic_check_t trans,bool save_orig)1403 int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog,
1404 bpf_aux_classic_check_t trans, bool save_orig)
1405 {
1406 unsigned int fsize = bpf_classic_proglen(fprog);
1407 struct bpf_prog *fp;
1408 int err;
1409
1410 /* Make sure new filter is there and in the right amounts. */
1411 if (!bpf_check_basics_ok(fprog->filter, fprog->len))
1412 return -EINVAL;
1413
1414 fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
1415 if (!fp)
1416 return -ENOMEM;
1417
1418 if (copy_from_user(fp->insns, fprog->filter, fsize)) {
1419 __bpf_prog_free(fp);
1420 return -EFAULT;
1421 }
1422
1423 fp->len = fprog->len;
1424 fp->orig_prog = NULL;
1425
1426 if (save_orig) {
1427 err = bpf_prog_store_orig_filter(fp, fprog);
1428 if (err) {
1429 __bpf_prog_free(fp);
1430 return -ENOMEM;
1431 }
1432 }
1433
1434 /* bpf_prepare_filter() already takes care of freeing
1435 * memory in case something goes wrong.
1436 */
1437 fp = bpf_prepare_filter(fp, trans);
1438 if (IS_ERR(fp))
1439 return PTR_ERR(fp);
1440
1441 *pfp = fp;
1442 return 0;
1443 }
1444 EXPORT_SYMBOL_GPL(bpf_prog_create_from_user);
1445
bpf_prog_destroy(struct bpf_prog * fp)1446 void bpf_prog_destroy(struct bpf_prog *fp)
1447 {
1448 __bpf_prog_release(fp);
1449 }
1450 EXPORT_SYMBOL_GPL(bpf_prog_destroy);
1451
__sk_attach_prog(struct bpf_prog * prog,struct sock * sk)1452 static int __sk_attach_prog(struct bpf_prog *prog, struct sock *sk)
1453 {
1454 struct sk_filter *fp, *old_fp;
1455
1456 fp = kmalloc(sizeof(*fp), GFP_KERNEL);
1457 if (!fp)
1458 return -ENOMEM;
1459
1460 fp->prog = prog;
1461
1462 if (!__sk_filter_charge(sk, fp)) {
1463 kfree(fp);
1464 return -ENOMEM;
1465 }
1466 refcount_set(&fp->refcnt, 1);
1467
1468 old_fp = rcu_dereference_protected(sk->sk_filter,
1469 lockdep_sock_is_held(sk));
1470 rcu_assign_pointer(sk->sk_filter, fp);
1471
1472 if (old_fp)
1473 sk_filter_uncharge(sk, old_fp);
1474
1475 return 0;
1476 }
1477
1478 static
__get_filter(struct sock_fprog * fprog,struct sock * sk)1479 struct bpf_prog *__get_filter(struct sock_fprog *fprog, struct sock *sk)
1480 {
1481 unsigned int fsize = bpf_classic_proglen(fprog);
1482 struct bpf_prog *prog;
1483 int err;
1484
1485 if (sock_flag(sk, SOCK_FILTER_LOCKED))
1486 return ERR_PTR(-EPERM);
1487
1488 /* Make sure new filter is there and in the right amounts. */
1489 if (!bpf_check_basics_ok(fprog->filter, fprog->len))
1490 return ERR_PTR(-EINVAL);
1491
1492 prog = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
1493 if (!prog)
1494 return ERR_PTR(-ENOMEM);
1495
1496 if (copy_from_user(prog->insns, fprog->filter, fsize)) {
1497 __bpf_prog_free(prog);
1498 return ERR_PTR(-EFAULT);
1499 }
1500
1501 prog->len = fprog->len;
1502
1503 err = bpf_prog_store_orig_filter(prog, fprog);
1504 if (err) {
1505 __bpf_prog_free(prog);
1506 return ERR_PTR(-ENOMEM);
1507 }
1508
1509 /* bpf_prepare_filter() already takes care of freeing
1510 * memory in case something goes wrong.
1511 */
1512 return bpf_prepare_filter(prog, NULL);
1513 }
1514
1515 /**
1516 * sk_attach_filter - attach a socket filter
1517 * @fprog: the filter program
1518 * @sk: the socket to use
1519 *
1520 * Attach the user's filter code. We first run some sanity checks on
1521 * it to make sure it does not explode on us later. If an error
1522 * occurs or there is insufficient memory for the filter a negative
1523 * errno code is returned. On success the return is zero.
1524 */
sk_attach_filter(struct sock_fprog * fprog,struct sock * sk)1525 int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk)
1526 {
1527 struct bpf_prog *prog = __get_filter(fprog, sk);
1528 int err;
1529
1530 if (IS_ERR(prog))
1531 return PTR_ERR(prog);
1532
1533 err = __sk_attach_prog(prog, sk);
1534 if (err < 0) {
1535 __bpf_prog_release(prog);
1536 return err;
1537 }
1538
1539 return 0;
1540 }
1541 EXPORT_SYMBOL_GPL(sk_attach_filter);
1542
sk_reuseport_attach_filter(struct sock_fprog * fprog,struct sock * sk)1543 int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk)
1544 {
1545 struct bpf_prog *prog = __get_filter(fprog, sk);
1546 int err;
1547
1548 if (IS_ERR(prog))
1549 return PTR_ERR(prog);
1550
1551 if (bpf_prog_size(prog->len) > sysctl_optmem_max)
1552 err = -ENOMEM;
1553 else
1554 err = reuseport_attach_prog(sk, prog);
1555
1556 if (err)
1557 __bpf_prog_release(prog);
1558
1559 return err;
1560 }
1561
__get_bpf(u32 ufd,struct sock * sk)1562 static struct bpf_prog *__get_bpf(u32 ufd, struct sock *sk)
1563 {
1564 if (sock_flag(sk, SOCK_FILTER_LOCKED))
1565 return ERR_PTR(-EPERM);
1566
1567 return bpf_prog_get_type(ufd, BPF_PROG_TYPE_SOCKET_FILTER);
1568 }
1569
sk_attach_bpf(u32 ufd,struct sock * sk)1570 int sk_attach_bpf(u32 ufd, struct sock *sk)
1571 {
1572 struct bpf_prog *prog = __get_bpf(ufd, sk);
1573 int err;
1574
1575 if (IS_ERR(prog))
1576 return PTR_ERR(prog);
1577
1578 err = __sk_attach_prog(prog, sk);
1579 if (err < 0) {
1580 bpf_prog_put(prog);
1581 return err;
1582 }
1583
1584 return 0;
1585 }
1586
sk_reuseport_attach_bpf(u32 ufd,struct sock * sk)1587 int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk)
1588 {
1589 struct bpf_prog *prog;
1590 int err;
1591
1592 if (sock_flag(sk, SOCK_FILTER_LOCKED))
1593 return -EPERM;
1594
1595 prog = bpf_prog_get_type(ufd, BPF_PROG_TYPE_SOCKET_FILTER);
1596 if (PTR_ERR(prog) == -EINVAL)
1597 prog = bpf_prog_get_type(ufd, BPF_PROG_TYPE_SK_REUSEPORT);
1598 if (IS_ERR(prog))
1599 return PTR_ERR(prog);
1600
1601 if (prog->type == BPF_PROG_TYPE_SK_REUSEPORT) {
1602 /* Like other non BPF_PROG_TYPE_SOCKET_FILTER
1603 * bpf prog (e.g. sockmap). It depends on the
1604 * limitation imposed by bpf_prog_load().
1605 * Hence, sysctl_optmem_max is not checked.
1606 */
1607 if ((sk->sk_type != SOCK_STREAM &&
1608 sk->sk_type != SOCK_DGRAM) ||
1609 (sk->sk_protocol != IPPROTO_UDP &&
1610 sk->sk_protocol != IPPROTO_TCP) ||
1611 (sk->sk_family != AF_INET &&
1612 sk->sk_family != AF_INET6)) {
1613 err = -ENOTSUPP;
1614 goto err_prog_put;
1615 }
1616 } else {
1617 /* BPF_PROG_TYPE_SOCKET_FILTER */
1618 if (bpf_prog_size(prog->len) > sysctl_optmem_max) {
1619 err = -ENOMEM;
1620 goto err_prog_put;
1621 }
1622 }
1623
1624 err = reuseport_attach_prog(sk, prog);
1625 err_prog_put:
1626 if (err)
1627 bpf_prog_put(prog);
1628
1629 return err;
1630 }
1631
sk_reuseport_prog_free(struct bpf_prog * prog)1632 void sk_reuseport_prog_free(struct bpf_prog *prog)
1633 {
1634 if (!prog)
1635 return;
1636
1637 if (prog->type == BPF_PROG_TYPE_SK_REUSEPORT)
1638 bpf_prog_put(prog);
1639 else
1640 bpf_prog_destroy(prog);
1641 }
1642
1643 struct bpf_scratchpad {
1644 union {
1645 __be32 diff[MAX_BPF_STACK / sizeof(__be32)];
1646 u8 buff[MAX_BPF_STACK];
1647 };
1648 };
1649
1650 static DEFINE_PER_CPU(struct bpf_scratchpad, bpf_sp);
1651
__bpf_try_make_writable(struct sk_buff * skb,unsigned int write_len)1652 static inline int __bpf_try_make_writable(struct sk_buff *skb,
1653 unsigned int write_len)
1654 {
1655 return skb_ensure_writable(skb, write_len);
1656 }
1657
bpf_try_make_writable(struct sk_buff * skb,unsigned int write_len)1658 static inline int bpf_try_make_writable(struct sk_buff *skb,
1659 unsigned int write_len)
1660 {
1661 int err = __bpf_try_make_writable(skb, write_len);
1662
1663 bpf_compute_data_pointers(skb);
1664 return err;
1665 }
1666
bpf_try_make_head_writable(struct sk_buff * skb)1667 static int bpf_try_make_head_writable(struct sk_buff *skb)
1668 {
1669 return bpf_try_make_writable(skb, skb_headlen(skb));
1670 }
1671
bpf_push_mac_rcsum(struct sk_buff * skb)1672 static inline void bpf_push_mac_rcsum(struct sk_buff *skb)
1673 {
1674 if (skb_at_tc_ingress(skb))
1675 skb_postpush_rcsum(skb, skb_mac_header(skb), skb->mac_len);
1676 }
1677
bpf_pull_mac_rcsum(struct sk_buff * skb)1678 static inline void bpf_pull_mac_rcsum(struct sk_buff *skb)
1679 {
1680 if (skb_at_tc_ingress(skb))
1681 skb_postpull_rcsum(skb, skb_mac_header(skb), skb->mac_len);
1682 }
1683
BPF_CALL_5(bpf_skb_store_bytes,struct sk_buff *,skb,u32,offset,const void *,from,u32,len,u64,flags)1684 BPF_CALL_5(bpf_skb_store_bytes, struct sk_buff *, skb, u32, offset,
1685 const void *, from, u32, len, u64, flags)
1686 {
1687 void *ptr;
1688
1689 if (unlikely(flags & ~(BPF_F_RECOMPUTE_CSUM | BPF_F_INVALIDATE_HASH)))
1690 return -EINVAL;
1691 if (unlikely(offset > 0xffff))
1692 return -EFAULT;
1693 if (unlikely(bpf_try_make_writable(skb, offset + len)))
1694 return -EFAULT;
1695
1696 ptr = skb->data + offset;
1697 if (flags & BPF_F_RECOMPUTE_CSUM)
1698 __skb_postpull_rcsum(skb, ptr, len, offset);
1699
1700 memcpy(ptr, from, len);
1701
1702 if (flags & BPF_F_RECOMPUTE_CSUM)
1703 __skb_postpush_rcsum(skb, ptr, len, offset);
1704 if (flags & BPF_F_INVALIDATE_HASH)
1705 skb_clear_hash(skb);
1706
1707 return 0;
1708 }
1709
1710 static const struct bpf_func_proto bpf_skb_store_bytes_proto = {
1711 .func = bpf_skb_store_bytes,
1712 .gpl_only = false,
1713 .ret_type = RET_INTEGER,
1714 .arg1_type = ARG_PTR_TO_CTX,
1715 .arg2_type = ARG_ANYTHING,
1716 .arg3_type = ARG_PTR_TO_MEM,
1717 .arg4_type = ARG_CONST_SIZE,
1718 .arg5_type = ARG_ANYTHING,
1719 };
1720
BPF_CALL_4(bpf_skb_load_bytes,const struct sk_buff *,skb,u32,offset,void *,to,u32,len)1721 BPF_CALL_4(bpf_skb_load_bytes, const struct sk_buff *, skb, u32, offset,
1722 void *, to, u32, len)
1723 {
1724 void *ptr;
1725
1726 if (unlikely(offset > 0xffff))
1727 goto err_clear;
1728
1729 ptr = skb_header_pointer(skb, offset, len, to);
1730 if (unlikely(!ptr))
1731 goto err_clear;
1732 if (ptr != to)
1733 memcpy(to, ptr, len);
1734
1735 return 0;
1736 err_clear:
1737 memset(to, 0, len);
1738 return -EFAULT;
1739 }
1740
1741 static const struct bpf_func_proto bpf_skb_load_bytes_proto = {
1742 .func = bpf_skb_load_bytes,
1743 .gpl_only = false,
1744 .ret_type = RET_INTEGER,
1745 .arg1_type = ARG_PTR_TO_CTX,
1746 .arg2_type = ARG_ANYTHING,
1747 .arg3_type = ARG_PTR_TO_UNINIT_MEM,
1748 .arg4_type = ARG_CONST_SIZE,
1749 };
1750
BPF_CALL_4(bpf_flow_dissector_load_bytes,const struct bpf_flow_dissector *,ctx,u32,offset,void *,to,u32,len)1751 BPF_CALL_4(bpf_flow_dissector_load_bytes,
1752 const struct bpf_flow_dissector *, ctx, u32, offset,
1753 void *, to, u32, len)
1754 {
1755 void *ptr;
1756
1757 if (unlikely(offset > 0xffff))
1758 goto err_clear;
1759
1760 if (unlikely(!ctx->skb))
1761 goto err_clear;
1762
1763 ptr = skb_header_pointer(ctx->skb, offset, len, to);
1764 if (unlikely(!ptr))
1765 goto err_clear;
1766 if (ptr != to)
1767 memcpy(to, ptr, len);
1768
1769 return 0;
1770 err_clear:
1771 memset(to, 0, len);
1772 return -EFAULT;
1773 }
1774
1775 static const struct bpf_func_proto bpf_flow_dissector_load_bytes_proto = {
1776 .func = bpf_flow_dissector_load_bytes,
1777 .gpl_only = false,
1778 .ret_type = RET_INTEGER,
1779 .arg1_type = ARG_PTR_TO_CTX,
1780 .arg2_type = ARG_ANYTHING,
1781 .arg3_type = ARG_PTR_TO_UNINIT_MEM,
1782 .arg4_type = ARG_CONST_SIZE,
1783 };
1784
BPF_CALL_5(bpf_skb_load_bytes_relative,const struct sk_buff *,skb,u32,offset,void *,to,u32,len,u32,start_header)1785 BPF_CALL_5(bpf_skb_load_bytes_relative, const struct sk_buff *, skb,
1786 u32, offset, void *, to, u32, len, u32, start_header)
1787 {
1788 u8 *end = skb_tail_pointer(skb);
1789 u8 *start, *ptr;
1790
1791 if (unlikely(offset > 0xffff))
1792 goto err_clear;
1793
1794 switch (start_header) {
1795 case BPF_HDR_START_MAC:
1796 if (unlikely(!skb_mac_header_was_set(skb)))
1797 goto err_clear;
1798 start = skb_mac_header(skb);
1799 break;
1800 case BPF_HDR_START_NET:
1801 start = skb_network_header(skb);
1802 break;
1803 default:
1804 goto err_clear;
1805 }
1806
1807 ptr = start + offset;
1808
1809 if (likely(ptr + len <= end)) {
1810 memcpy(to, ptr, len);
1811 return 0;
1812 }
1813
1814 err_clear:
1815 memset(to, 0, len);
1816 return -EFAULT;
1817 }
1818
1819 static const struct bpf_func_proto bpf_skb_load_bytes_relative_proto = {
1820 .func = bpf_skb_load_bytes_relative,
1821 .gpl_only = false,
1822 .ret_type = RET_INTEGER,
1823 .arg1_type = ARG_PTR_TO_CTX,
1824 .arg2_type = ARG_ANYTHING,
1825 .arg3_type = ARG_PTR_TO_UNINIT_MEM,
1826 .arg4_type = ARG_CONST_SIZE,
1827 .arg5_type = ARG_ANYTHING,
1828 };
1829
BPF_CALL_2(bpf_skb_pull_data,struct sk_buff *,skb,u32,len)1830 BPF_CALL_2(bpf_skb_pull_data, struct sk_buff *, skb, u32, len)
1831 {
1832 /* Idea is the following: should the needed direct read/write
1833 * test fail during runtime, we can pull in more data and redo
1834 * again, since implicitly, we invalidate previous checks here.
1835 *
1836 * Or, since we know how much we need to make read/writeable,
1837 * this can be done once at the program beginning for direct
1838 * access case. By this we overcome limitations of only current
1839 * headroom being accessible.
1840 */
1841 return bpf_try_make_writable(skb, len ? : skb_headlen(skb));
1842 }
1843
1844 static const struct bpf_func_proto bpf_skb_pull_data_proto = {
1845 .func = bpf_skb_pull_data,
1846 .gpl_only = false,
1847 .ret_type = RET_INTEGER,
1848 .arg1_type = ARG_PTR_TO_CTX,
1849 .arg2_type = ARG_ANYTHING,
1850 };
1851
BPF_CALL_1(bpf_sk_fullsock,struct sock *,sk)1852 BPF_CALL_1(bpf_sk_fullsock, struct sock *, sk)
1853 {
1854 return sk_fullsock(sk) ? (unsigned long)sk : (unsigned long)NULL;
1855 }
1856
1857 static const struct bpf_func_proto bpf_sk_fullsock_proto = {
1858 .func = bpf_sk_fullsock,
1859 .gpl_only = false,
1860 .ret_type = RET_PTR_TO_SOCKET_OR_NULL,
1861 .arg1_type = ARG_PTR_TO_SOCK_COMMON,
1862 };
1863
sk_skb_try_make_writable(struct sk_buff * skb,unsigned int write_len)1864 static inline int sk_skb_try_make_writable(struct sk_buff *skb,
1865 unsigned int write_len)
1866 {
1867 return __bpf_try_make_writable(skb, write_len);
1868 }
1869
BPF_CALL_2(sk_skb_pull_data,struct sk_buff *,skb,u32,len)1870 BPF_CALL_2(sk_skb_pull_data, struct sk_buff *, skb, u32, len)
1871 {
1872 /* Idea is the following: should the needed direct read/write
1873 * test fail during runtime, we can pull in more data and redo
1874 * again, since implicitly, we invalidate previous checks here.
1875 *
1876 * Or, since we know how much we need to make read/writeable,
1877 * this can be done once at the program beginning for direct
1878 * access case. By this we overcome limitations of only current
1879 * headroom being accessible.
1880 */
1881 return sk_skb_try_make_writable(skb, len ? : skb_headlen(skb));
1882 }
1883
1884 static const struct bpf_func_proto sk_skb_pull_data_proto = {
1885 .func = sk_skb_pull_data,
1886 .gpl_only = false,
1887 .ret_type = RET_INTEGER,
1888 .arg1_type = ARG_PTR_TO_CTX,
1889 .arg2_type = ARG_ANYTHING,
1890 };
1891
BPF_CALL_5(bpf_l3_csum_replace,struct sk_buff *,skb,u32,offset,u64,from,u64,to,u64,flags)1892 BPF_CALL_5(bpf_l3_csum_replace, struct sk_buff *, skb, u32, offset,
1893 u64, from, u64, to, u64, flags)
1894 {
1895 __sum16 *ptr;
1896
1897 if (unlikely(flags & ~(BPF_F_HDR_FIELD_MASK)))
1898 return -EINVAL;
1899 if (unlikely(offset > 0xffff || offset & 1))
1900 return -EFAULT;
1901 if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr))))
1902 return -EFAULT;
1903
1904 ptr = (__sum16 *)(skb->data + offset);
1905 switch (flags & BPF_F_HDR_FIELD_MASK) {
1906 case 0:
1907 if (unlikely(from != 0))
1908 return -EINVAL;
1909
1910 csum_replace_by_diff(ptr, to);
1911 break;
1912 case 2:
1913 csum_replace2(ptr, from, to);
1914 break;
1915 case 4:
1916 csum_replace4(ptr, from, to);
1917 break;
1918 default:
1919 return -EINVAL;
1920 }
1921
1922 return 0;
1923 }
1924
1925 static const struct bpf_func_proto bpf_l3_csum_replace_proto = {
1926 .func = bpf_l3_csum_replace,
1927 .gpl_only = false,
1928 .ret_type = RET_INTEGER,
1929 .arg1_type = ARG_PTR_TO_CTX,
1930 .arg2_type = ARG_ANYTHING,
1931 .arg3_type = ARG_ANYTHING,
1932 .arg4_type = ARG_ANYTHING,
1933 .arg5_type = ARG_ANYTHING,
1934 };
1935
BPF_CALL_5(bpf_l4_csum_replace,struct sk_buff *,skb,u32,offset,u64,from,u64,to,u64,flags)1936 BPF_CALL_5(bpf_l4_csum_replace, struct sk_buff *, skb, u32, offset,
1937 u64, from, u64, to, u64, flags)
1938 {
1939 bool is_pseudo = flags & BPF_F_PSEUDO_HDR;
1940 bool is_mmzero = flags & BPF_F_MARK_MANGLED_0;
1941 bool do_mforce = flags & BPF_F_MARK_ENFORCE;
1942 __sum16 *ptr;
1943
1944 if (unlikely(flags & ~(BPF_F_MARK_MANGLED_0 | BPF_F_MARK_ENFORCE |
1945 BPF_F_PSEUDO_HDR | BPF_F_HDR_FIELD_MASK)))
1946 return -EINVAL;
1947 if (unlikely(offset > 0xffff || offset & 1))
1948 return -EFAULT;
1949 if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr))))
1950 return -EFAULT;
1951
1952 ptr = (__sum16 *)(skb->data + offset);
1953 if (is_mmzero && !do_mforce && !*ptr)
1954 return 0;
1955
1956 switch (flags & BPF_F_HDR_FIELD_MASK) {
1957 case 0:
1958 if (unlikely(from != 0))
1959 return -EINVAL;
1960
1961 inet_proto_csum_replace_by_diff(ptr, skb, to, is_pseudo);
1962 break;
1963 case 2:
1964 inet_proto_csum_replace2(ptr, skb, from, to, is_pseudo);
1965 break;
1966 case 4:
1967 inet_proto_csum_replace4(ptr, skb, from, to, is_pseudo);
1968 break;
1969 default:
1970 return -EINVAL;
1971 }
1972
1973 if (is_mmzero && !*ptr)
1974 *ptr = CSUM_MANGLED_0;
1975 return 0;
1976 }
1977
1978 static const struct bpf_func_proto bpf_l4_csum_replace_proto = {
1979 .func = bpf_l4_csum_replace,
1980 .gpl_only = false,
1981 .ret_type = RET_INTEGER,
1982 .arg1_type = ARG_PTR_TO_CTX,
1983 .arg2_type = ARG_ANYTHING,
1984 .arg3_type = ARG_ANYTHING,
1985 .arg4_type = ARG_ANYTHING,
1986 .arg5_type = ARG_ANYTHING,
1987 };
1988
BPF_CALL_5(bpf_csum_diff,__be32 *,from,u32,from_size,__be32 *,to,u32,to_size,__wsum,seed)1989 BPF_CALL_5(bpf_csum_diff, __be32 *, from, u32, from_size,
1990 __be32 *, to, u32, to_size, __wsum, seed)
1991 {
1992 struct bpf_scratchpad *sp = this_cpu_ptr(&bpf_sp);
1993 u32 diff_size = from_size + to_size;
1994 int i, j = 0;
1995
1996 /* This is quite flexible, some examples:
1997 *
1998 * from_size == 0, to_size > 0, seed := csum --> pushing data
1999 * from_size > 0, to_size == 0, seed := csum --> pulling data
2000 * from_size > 0, to_size > 0, seed := 0 --> diffing data
2001 *
2002 * Even for diffing, from_size and to_size don't need to be equal.
2003 */
2004 if (unlikely(((from_size | to_size) & (sizeof(__be32) - 1)) ||
2005 diff_size > sizeof(sp->diff)))
2006 return -EINVAL;
2007
2008 for (i = 0; i < from_size / sizeof(__be32); i++, j++)
2009 sp->diff[j] = ~from[i];
2010 for (i = 0; i < to_size / sizeof(__be32); i++, j++)
2011 sp->diff[j] = to[i];
2012
2013 return csum_partial(sp->diff, diff_size, seed);
2014 }
2015
2016 static const struct bpf_func_proto bpf_csum_diff_proto = {
2017 .func = bpf_csum_diff,
2018 .gpl_only = false,
2019 .pkt_access = true,
2020 .ret_type = RET_INTEGER,
2021 .arg1_type = ARG_PTR_TO_MEM_OR_NULL,
2022 .arg2_type = ARG_CONST_SIZE_OR_ZERO,
2023 .arg3_type = ARG_PTR_TO_MEM_OR_NULL,
2024 .arg4_type = ARG_CONST_SIZE_OR_ZERO,
2025 .arg5_type = ARG_ANYTHING,
2026 };
2027
BPF_CALL_2(bpf_csum_update,struct sk_buff *,skb,__wsum,csum)2028 BPF_CALL_2(bpf_csum_update, struct sk_buff *, skb, __wsum, csum)
2029 {
2030 /* The interface is to be used in combination with bpf_csum_diff()
2031 * for direct packet writes. csum rotation for alignment as well
2032 * as emulating csum_sub() can be done from the eBPF program.
2033 */
2034 if (skb->ip_summed == CHECKSUM_COMPLETE)
2035 return (skb->csum = csum_add(skb->csum, csum));
2036
2037 return -ENOTSUPP;
2038 }
2039
2040 static const struct bpf_func_proto bpf_csum_update_proto = {
2041 .func = bpf_csum_update,
2042 .gpl_only = false,
2043 .ret_type = RET_INTEGER,
2044 .arg1_type = ARG_PTR_TO_CTX,
2045 .arg2_type = ARG_ANYTHING,
2046 };
2047
BPF_CALL_2(bpf_csum_level,struct sk_buff *,skb,u64,level)2048 BPF_CALL_2(bpf_csum_level, struct sk_buff *, skb, u64, level)
2049 {
2050 /* The interface is to be used in combination with bpf_skb_adjust_room()
2051 * for encap/decap of packet headers when BPF_F_ADJ_ROOM_NO_CSUM_RESET
2052 * is passed as flags, for example.
2053 */
2054 switch (level) {
2055 case BPF_CSUM_LEVEL_INC:
2056 __skb_incr_checksum_unnecessary(skb);
2057 break;
2058 case BPF_CSUM_LEVEL_DEC:
2059 __skb_decr_checksum_unnecessary(skb);
2060 break;
2061 case BPF_CSUM_LEVEL_RESET:
2062 __skb_reset_checksum_unnecessary(skb);
2063 break;
2064 case BPF_CSUM_LEVEL_QUERY:
2065 return skb->ip_summed == CHECKSUM_UNNECESSARY ?
2066 skb->csum_level : -EACCES;
2067 default:
2068 return -EINVAL;
2069 }
2070
2071 return 0;
2072 }
2073
2074 static const struct bpf_func_proto bpf_csum_level_proto = {
2075 .func = bpf_csum_level,
2076 .gpl_only = false,
2077 .ret_type = RET_INTEGER,
2078 .arg1_type = ARG_PTR_TO_CTX,
2079 .arg2_type = ARG_ANYTHING,
2080 };
2081
__bpf_rx_skb(struct net_device * dev,struct sk_buff * skb)2082 static inline int __bpf_rx_skb(struct net_device *dev, struct sk_buff *skb)
2083 {
2084 return dev_forward_skb_nomtu(dev, skb);
2085 }
2086
__bpf_rx_skb_no_mac(struct net_device * dev,struct sk_buff * skb)2087 static inline int __bpf_rx_skb_no_mac(struct net_device *dev,
2088 struct sk_buff *skb)
2089 {
2090 int ret = ____dev_forward_skb(dev, skb, false);
2091
2092 if (likely(!ret)) {
2093 skb->dev = dev;
2094 ret = netif_rx(skb);
2095 }
2096
2097 return ret;
2098 }
2099
__bpf_tx_skb(struct net_device * dev,struct sk_buff * skb)2100 static inline int __bpf_tx_skb(struct net_device *dev, struct sk_buff *skb)
2101 {
2102 int ret;
2103
2104 if (dev_xmit_recursion()) {
2105 net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n");
2106 kfree_skb(skb);
2107 return -ENETDOWN;
2108 }
2109
2110 skb->dev = dev;
2111 skb->tstamp = 0;
2112
2113 dev_xmit_recursion_inc();
2114 ret = dev_queue_xmit(skb);
2115 dev_xmit_recursion_dec();
2116
2117 return ret;
2118 }
2119
__bpf_redirect_no_mac(struct sk_buff * skb,struct net_device * dev,u32 flags)2120 static int __bpf_redirect_no_mac(struct sk_buff *skb, struct net_device *dev,
2121 u32 flags)
2122 {
2123 unsigned int mlen = skb_network_offset(skb);
2124
2125 if (mlen) {
2126 __skb_pull(skb, mlen);
2127
2128 /* At ingress, the mac header has already been pulled once.
2129 * At egress, skb_pospull_rcsum has to be done in case that
2130 * the skb is originated from ingress (i.e. a forwarded skb)
2131 * to ensure that rcsum starts at net header.
2132 */
2133 if (!skb_at_tc_ingress(skb))
2134 skb_postpull_rcsum(skb, skb_mac_header(skb), mlen);
2135 }
2136 skb_pop_mac_header(skb);
2137 skb_reset_mac_len(skb);
2138 return flags & BPF_F_INGRESS ?
2139 __bpf_rx_skb_no_mac(dev, skb) : __bpf_tx_skb(dev, skb);
2140 }
2141
__bpf_redirect_common(struct sk_buff * skb,struct net_device * dev,u32 flags)2142 static int __bpf_redirect_common(struct sk_buff *skb, struct net_device *dev,
2143 u32 flags)
2144 {
2145 /* Verify that a link layer header is carried */
2146 if (unlikely(skb->mac_header >= skb->network_header)) {
2147 kfree_skb(skb);
2148 return -ERANGE;
2149 }
2150
2151 bpf_push_mac_rcsum(skb);
2152 return flags & BPF_F_INGRESS ?
2153 __bpf_rx_skb(dev, skb) : __bpf_tx_skb(dev, skb);
2154 }
2155
__bpf_redirect(struct sk_buff * skb,struct net_device * dev,u32 flags)2156 static int __bpf_redirect(struct sk_buff *skb, struct net_device *dev,
2157 u32 flags)
2158 {
2159 if (dev_is_mac_header_xmit(dev))
2160 return __bpf_redirect_common(skb, dev, flags);
2161 else
2162 return __bpf_redirect_no_mac(skb, dev, flags);
2163 }
2164
2165 #if IS_ENABLED(CONFIG_IPV6)
bpf_out_neigh_v6(struct net * net,struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2166 static int bpf_out_neigh_v6(struct net *net, struct sk_buff *skb,
2167 struct net_device *dev, struct bpf_nh_params *nh)
2168 {
2169 u32 hh_len = LL_RESERVED_SPACE(dev);
2170 const struct in6_addr *nexthop;
2171 struct dst_entry *dst = NULL;
2172 struct neighbour *neigh;
2173
2174 if (dev_xmit_recursion()) {
2175 net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n");
2176 goto out_drop;
2177 }
2178
2179 skb->dev = dev;
2180 skb->tstamp = 0;
2181
2182 if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) {
2183 skb = skb_expand_head(skb, hh_len);
2184 if (!skb)
2185 return -ENOMEM;
2186 }
2187
2188 rcu_read_lock_bh();
2189 if (!nh) {
2190 dst = skb_dst(skb);
2191 nexthop = rt6_nexthop(container_of(dst, struct rt6_info, dst),
2192 &ipv6_hdr(skb)->daddr);
2193 } else {
2194 nexthop = &nh->ipv6_nh;
2195 }
2196 neigh = ip_neigh_gw6(dev, nexthop);
2197 if (likely(!IS_ERR(neigh))) {
2198 int ret;
2199
2200 sock_confirm_neigh(skb, neigh);
2201 dev_xmit_recursion_inc();
2202 ret = neigh_output(neigh, skb, false);
2203 dev_xmit_recursion_dec();
2204 rcu_read_unlock_bh();
2205 return ret;
2206 }
2207 rcu_read_unlock_bh();
2208 if (dst)
2209 IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
2210 out_drop:
2211 kfree_skb(skb);
2212 return -ENETDOWN;
2213 }
2214
__bpf_redirect_neigh_v6(struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2215 static int __bpf_redirect_neigh_v6(struct sk_buff *skb, struct net_device *dev,
2216 struct bpf_nh_params *nh)
2217 {
2218 const struct ipv6hdr *ip6h = ipv6_hdr(skb);
2219 struct net *net = dev_net(dev);
2220 int err, ret = NET_XMIT_DROP;
2221
2222 if (!nh) {
2223 struct dst_entry *dst;
2224 struct flowi6 fl6 = {
2225 .flowi6_flags = FLOWI_FLAG_ANYSRC,
2226 .flowi6_mark = skb->mark,
2227 .flowlabel = ip6_flowinfo(ip6h),
2228 .flowi6_oif = dev->ifindex,
2229 .flowi6_proto = ip6h->nexthdr,
2230 .daddr = ip6h->daddr,
2231 .saddr = ip6h->saddr,
2232 };
2233
2234 dst = ipv6_stub->ipv6_dst_lookup_flow(net, NULL, &fl6, NULL);
2235 if (IS_ERR(dst))
2236 goto out_drop;
2237
2238 skb_dst_set(skb, dst);
2239 } else if (nh->nh_family != AF_INET6) {
2240 goto out_drop;
2241 }
2242
2243 err = bpf_out_neigh_v6(net, skb, dev, nh);
2244 if (unlikely(net_xmit_eval(err)))
2245 dev->stats.tx_errors++;
2246 else
2247 ret = NET_XMIT_SUCCESS;
2248 goto out_xmit;
2249 out_drop:
2250 dev->stats.tx_errors++;
2251 kfree_skb(skb);
2252 out_xmit:
2253 return ret;
2254 }
2255 #else
__bpf_redirect_neigh_v6(struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2256 static int __bpf_redirect_neigh_v6(struct sk_buff *skb, struct net_device *dev,
2257 struct bpf_nh_params *nh)
2258 {
2259 kfree_skb(skb);
2260 return NET_XMIT_DROP;
2261 }
2262 #endif /* CONFIG_IPV6 */
2263
2264 #if IS_ENABLED(CONFIG_INET)
bpf_out_neigh_v4(struct net * net,struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2265 static int bpf_out_neigh_v4(struct net *net, struct sk_buff *skb,
2266 struct net_device *dev, struct bpf_nh_params *nh)
2267 {
2268 u32 hh_len = LL_RESERVED_SPACE(dev);
2269 struct neighbour *neigh;
2270 bool is_v6gw = false;
2271
2272 if (dev_xmit_recursion()) {
2273 net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n");
2274 goto out_drop;
2275 }
2276
2277 skb->dev = dev;
2278 skb->tstamp = 0;
2279
2280 if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) {
2281 skb = skb_expand_head(skb, hh_len);
2282 if (!skb)
2283 return -ENOMEM;
2284 }
2285
2286 rcu_read_lock_bh();
2287 if (!nh) {
2288 struct dst_entry *dst = skb_dst(skb);
2289 struct rtable *rt = container_of(dst, struct rtable, dst);
2290
2291 neigh = ip_neigh_for_gw(rt, skb, &is_v6gw);
2292 } else if (nh->nh_family == AF_INET6) {
2293 neigh = ip_neigh_gw6(dev, &nh->ipv6_nh);
2294 is_v6gw = true;
2295 } else if (nh->nh_family == AF_INET) {
2296 neigh = ip_neigh_gw4(dev, nh->ipv4_nh);
2297 } else {
2298 rcu_read_unlock_bh();
2299 goto out_drop;
2300 }
2301
2302 if (likely(!IS_ERR(neigh))) {
2303 int ret;
2304
2305 sock_confirm_neigh(skb, neigh);
2306 dev_xmit_recursion_inc();
2307 ret = neigh_output(neigh, skb, is_v6gw);
2308 dev_xmit_recursion_dec();
2309 rcu_read_unlock_bh();
2310 return ret;
2311 }
2312 rcu_read_unlock_bh();
2313 out_drop:
2314 kfree_skb(skb);
2315 return -ENETDOWN;
2316 }
2317
__bpf_redirect_neigh_v4(struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2318 static int __bpf_redirect_neigh_v4(struct sk_buff *skb, struct net_device *dev,
2319 struct bpf_nh_params *nh)
2320 {
2321 const struct iphdr *ip4h = ip_hdr(skb);
2322 struct net *net = dev_net(dev);
2323 int err, ret = NET_XMIT_DROP;
2324
2325 if (!nh) {
2326 struct flowi4 fl4 = {
2327 .flowi4_flags = FLOWI_FLAG_ANYSRC,
2328 .flowi4_mark = skb->mark,
2329 .flowi4_tos = RT_TOS(ip4h->tos),
2330 .flowi4_oif = dev->ifindex,
2331 .flowi4_proto = ip4h->protocol,
2332 .daddr = ip4h->daddr,
2333 .saddr = ip4h->saddr,
2334 };
2335 struct rtable *rt;
2336
2337 rt = ip_route_output_flow(net, &fl4, NULL);
2338 if (IS_ERR(rt))
2339 goto out_drop;
2340 if (rt->rt_type != RTN_UNICAST && rt->rt_type != RTN_LOCAL) {
2341 ip_rt_put(rt);
2342 goto out_drop;
2343 }
2344
2345 skb_dst_set(skb, &rt->dst);
2346 }
2347
2348 err = bpf_out_neigh_v4(net, skb, dev, nh);
2349 if (unlikely(net_xmit_eval(err)))
2350 dev->stats.tx_errors++;
2351 else
2352 ret = NET_XMIT_SUCCESS;
2353 goto out_xmit;
2354 out_drop:
2355 dev->stats.tx_errors++;
2356 kfree_skb(skb);
2357 out_xmit:
2358 return ret;
2359 }
2360 #else
__bpf_redirect_neigh_v4(struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2361 static int __bpf_redirect_neigh_v4(struct sk_buff *skb, struct net_device *dev,
2362 struct bpf_nh_params *nh)
2363 {
2364 kfree_skb(skb);
2365 return NET_XMIT_DROP;
2366 }
2367 #endif /* CONFIG_INET */
2368
__bpf_redirect_neigh(struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2369 static int __bpf_redirect_neigh(struct sk_buff *skb, struct net_device *dev,
2370 struct bpf_nh_params *nh)
2371 {
2372 struct ethhdr *ethh = eth_hdr(skb);
2373
2374 if (unlikely(skb->mac_header >= skb->network_header))
2375 goto out;
2376 bpf_push_mac_rcsum(skb);
2377 if (is_multicast_ether_addr(ethh->h_dest))
2378 goto out;
2379
2380 skb_pull(skb, sizeof(*ethh));
2381 skb_unset_mac_header(skb);
2382 skb_reset_network_header(skb);
2383
2384 if (skb->protocol == htons(ETH_P_IP))
2385 return __bpf_redirect_neigh_v4(skb, dev, nh);
2386 else if (skb->protocol == htons(ETH_P_IPV6))
2387 return __bpf_redirect_neigh_v6(skb, dev, nh);
2388 out:
2389 kfree_skb(skb);
2390 return -ENOTSUPP;
2391 }
2392
2393 /* Internal, non-exposed redirect flags. */
2394 enum {
2395 BPF_F_NEIGH = (1ULL << 1),
2396 BPF_F_PEER = (1ULL << 2),
2397 BPF_F_NEXTHOP = (1ULL << 3),
2398 #define BPF_F_REDIRECT_INTERNAL (BPF_F_NEIGH | BPF_F_PEER | BPF_F_NEXTHOP)
2399 };
2400
BPF_CALL_3(bpf_clone_redirect,struct sk_buff *,skb,u32,ifindex,u64,flags)2401 BPF_CALL_3(bpf_clone_redirect, struct sk_buff *, skb, u32, ifindex, u64, flags)
2402 {
2403 struct net_device *dev;
2404 struct sk_buff *clone;
2405 int ret;
2406
2407 if (unlikely(flags & (~(BPF_F_INGRESS) | BPF_F_REDIRECT_INTERNAL)))
2408 return -EINVAL;
2409
2410 dev = dev_get_by_index_rcu(dev_net(skb->dev), ifindex);
2411 if (unlikely(!dev))
2412 return -EINVAL;
2413
2414 clone = skb_clone(skb, GFP_ATOMIC);
2415 if (unlikely(!clone))
2416 return -ENOMEM;
2417
2418 /* For direct write, we need to keep the invariant that the skbs
2419 * we're dealing with need to be uncloned. Should uncloning fail
2420 * here, we need to free the just generated clone to unclone once
2421 * again.
2422 */
2423 ret = bpf_try_make_head_writable(skb);
2424 if (unlikely(ret)) {
2425 kfree_skb(clone);
2426 return -ENOMEM;
2427 }
2428
2429 return __bpf_redirect(clone, dev, flags);
2430 }
2431
2432 static const struct bpf_func_proto bpf_clone_redirect_proto = {
2433 .func = bpf_clone_redirect,
2434 .gpl_only = false,
2435 .ret_type = RET_INTEGER,
2436 .arg1_type = ARG_PTR_TO_CTX,
2437 .arg2_type = ARG_ANYTHING,
2438 .arg3_type = ARG_ANYTHING,
2439 };
2440
2441 DEFINE_PER_CPU(struct bpf_redirect_info, bpf_redirect_info);
2442 EXPORT_PER_CPU_SYMBOL_GPL(bpf_redirect_info);
2443
skb_do_redirect(struct sk_buff * skb)2444 int skb_do_redirect(struct sk_buff *skb)
2445 {
2446 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
2447 struct net *net = dev_net(skb->dev);
2448 struct net_device *dev;
2449 u32 flags = ri->flags;
2450
2451 dev = dev_get_by_index_rcu(net, ri->tgt_index);
2452 ri->tgt_index = 0;
2453 ri->flags = 0;
2454 if (unlikely(!dev))
2455 goto out_drop;
2456 if (flags & BPF_F_PEER) {
2457 const struct net_device_ops *ops = dev->netdev_ops;
2458
2459 if (unlikely(!ops->ndo_get_peer_dev ||
2460 !skb_at_tc_ingress(skb)))
2461 goto out_drop;
2462 dev = ops->ndo_get_peer_dev(dev);
2463 if (unlikely(!dev ||
2464 !(dev->flags & IFF_UP) ||
2465 net_eq(net, dev_net(dev))))
2466 goto out_drop;
2467 skb->dev = dev;
2468 return -EAGAIN;
2469 }
2470 return flags & BPF_F_NEIGH ?
2471 __bpf_redirect_neigh(skb, dev, flags & BPF_F_NEXTHOP ?
2472 &ri->nh : NULL) :
2473 __bpf_redirect(skb, dev, flags);
2474 out_drop:
2475 kfree_skb(skb);
2476 return -EINVAL;
2477 }
2478
BPF_CALL_2(bpf_redirect,u32,ifindex,u64,flags)2479 BPF_CALL_2(bpf_redirect, u32, ifindex, u64, flags)
2480 {
2481 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
2482
2483 if (unlikely(flags & (~(BPF_F_INGRESS) | BPF_F_REDIRECT_INTERNAL)))
2484 return TC_ACT_SHOT;
2485
2486 ri->flags = flags;
2487 ri->tgt_index = ifindex;
2488
2489 return TC_ACT_REDIRECT;
2490 }
2491
2492 static const struct bpf_func_proto bpf_redirect_proto = {
2493 .func = bpf_redirect,
2494 .gpl_only = false,
2495 .ret_type = RET_INTEGER,
2496 .arg1_type = ARG_ANYTHING,
2497 .arg2_type = ARG_ANYTHING,
2498 };
2499
BPF_CALL_2(bpf_redirect_peer,u32,ifindex,u64,flags)2500 BPF_CALL_2(bpf_redirect_peer, u32, ifindex, u64, flags)
2501 {
2502 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
2503
2504 if (unlikely(flags))
2505 return TC_ACT_SHOT;
2506
2507 ri->flags = BPF_F_PEER;
2508 ri->tgt_index = ifindex;
2509
2510 return TC_ACT_REDIRECT;
2511 }
2512
2513 static const struct bpf_func_proto bpf_redirect_peer_proto = {
2514 .func = bpf_redirect_peer,
2515 .gpl_only = false,
2516 .ret_type = RET_INTEGER,
2517 .arg1_type = ARG_ANYTHING,
2518 .arg2_type = ARG_ANYTHING,
2519 };
2520
BPF_CALL_4(bpf_redirect_neigh,u32,ifindex,struct bpf_redir_neigh *,params,int,plen,u64,flags)2521 BPF_CALL_4(bpf_redirect_neigh, u32, ifindex, struct bpf_redir_neigh *, params,
2522 int, plen, u64, flags)
2523 {
2524 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
2525
2526 if (unlikely((plen && plen < sizeof(*params)) || flags))
2527 return TC_ACT_SHOT;
2528
2529 ri->flags = BPF_F_NEIGH | (plen ? BPF_F_NEXTHOP : 0);
2530 ri->tgt_index = ifindex;
2531
2532 BUILD_BUG_ON(sizeof(struct bpf_redir_neigh) != sizeof(struct bpf_nh_params));
2533 if (plen)
2534 memcpy(&ri->nh, params, sizeof(ri->nh));
2535
2536 return TC_ACT_REDIRECT;
2537 }
2538
2539 static const struct bpf_func_proto bpf_redirect_neigh_proto = {
2540 .func = bpf_redirect_neigh,
2541 .gpl_only = false,
2542 .ret_type = RET_INTEGER,
2543 .arg1_type = ARG_ANYTHING,
2544 .arg2_type = ARG_PTR_TO_MEM_OR_NULL,
2545 .arg3_type = ARG_CONST_SIZE_OR_ZERO,
2546 .arg4_type = ARG_ANYTHING,
2547 };
2548
BPF_CALL_2(bpf_msg_apply_bytes,struct sk_msg *,msg,u32,bytes)2549 BPF_CALL_2(bpf_msg_apply_bytes, struct sk_msg *, msg, u32, bytes)
2550 {
2551 msg->apply_bytes = bytes;
2552 return 0;
2553 }
2554
2555 static const struct bpf_func_proto bpf_msg_apply_bytes_proto = {
2556 .func = bpf_msg_apply_bytes,
2557 .gpl_only = false,
2558 .ret_type = RET_INTEGER,
2559 .arg1_type = ARG_PTR_TO_CTX,
2560 .arg2_type = ARG_ANYTHING,
2561 };
2562
BPF_CALL_2(bpf_msg_cork_bytes,struct sk_msg *,msg,u32,bytes)2563 BPF_CALL_2(bpf_msg_cork_bytes, struct sk_msg *, msg, u32, bytes)
2564 {
2565 msg->cork_bytes = bytes;
2566 return 0;
2567 }
2568
2569 static const struct bpf_func_proto bpf_msg_cork_bytes_proto = {
2570 .func = bpf_msg_cork_bytes,
2571 .gpl_only = false,
2572 .ret_type = RET_INTEGER,
2573 .arg1_type = ARG_PTR_TO_CTX,
2574 .arg2_type = ARG_ANYTHING,
2575 };
2576
BPF_CALL_4(bpf_msg_pull_data,struct sk_msg *,msg,u32,start,u32,end,u64,flags)2577 BPF_CALL_4(bpf_msg_pull_data, struct sk_msg *, msg, u32, start,
2578 u32, end, u64, flags)
2579 {
2580 u32 len = 0, offset = 0, copy = 0, poffset = 0, bytes = end - start;
2581 u32 first_sge, last_sge, i, shift, bytes_sg_total;
2582 struct scatterlist *sge;
2583 u8 *raw, *to, *from;
2584 struct page *page;
2585
2586 if (unlikely(flags || end <= start))
2587 return -EINVAL;
2588
2589 /* First find the starting scatterlist element */
2590 i = msg->sg.start;
2591 do {
2592 offset += len;
2593 len = sk_msg_elem(msg, i)->length;
2594 if (start < offset + len)
2595 break;
2596 sk_msg_iter_var_next(i);
2597 } while (i != msg->sg.end);
2598
2599 if (unlikely(start >= offset + len))
2600 return -EINVAL;
2601
2602 first_sge = i;
2603 /* The start may point into the sg element so we need to also
2604 * account for the headroom.
2605 */
2606 bytes_sg_total = start - offset + bytes;
2607 if (!test_bit(i, &msg->sg.copy) && bytes_sg_total <= len)
2608 goto out;
2609
2610 /* At this point we need to linearize multiple scatterlist
2611 * elements or a single shared page. Either way we need to
2612 * copy into a linear buffer exclusively owned by BPF. Then
2613 * place the buffer in the scatterlist and fixup the original
2614 * entries by removing the entries now in the linear buffer
2615 * and shifting the remaining entries. For now we do not try
2616 * to copy partial entries to avoid complexity of running out
2617 * of sg_entry slots. The downside is reading a single byte
2618 * will copy the entire sg entry.
2619 */
2620 do {
2621 copy += sk_msg_elem(msg, i)->length;
2622 sk_msg_iter_var_next(i);
2623 if (bytes_sg_total <= copy)
2624 break;
2625 } while (i != msg->sg.end);
2626 last_sge = i;
2627
2628 if (unlikely(bytes_sg_total > copy))
2629 return -EINVAL;
2630
2631 page = alloc_pages(__GFP_NOWARN | GFP_ATOMIC | __GFP_COMP,
2632 get_order(copy));
2633 if (unlikely(!page))
2634 return -ENOMEM;
2635
2636 raw = page_address(page);
2637 i = first_sge;
2638 do {
2639 sge = sk_msg_elem(msg, i);
2640 from = sg_virt(sge);
2641 len = sge->length;
2642 to = raw + poffset;
2643
2644 memcpy(to, from, len);
2645 poffset += len;
2646 sge->length = 0;
2647 put_page(sg_page(sge));
2648
2649 sk_msg_iter_var_next(i);
2650 } while (i != last_sge);
2651
2652 sg_set_page(&msg->sg.data[first_sge], page, copy, 0);
2653
2654 /* To repair sg ring we need to shift entries. If we only
2655 * had a single entry though we can just replace it and
2656 * be done. Otherwise walk the ring and shift the entries.
2657 */
2658 WARN_ON_ONCE(last_sge == first_sge);
2659 shift = last_sge > first_sge ?
2660 last_sge - first_sge - 1 :
2661 NR_MSG_FRAG_IDS - first_sge + last_sge - 1;
2662 if (!shift)
2663 goto out;
2664
2665 i = first_sge;
2666 sk_msg_iter_var_next(i);
2667 do {
2668 u32 move_from;
2669
2670 if (i + shift >= NR_MSG_FRAG_IDS)
2671 move_from = i + shift - NR_MSG_FRAG_IDS;
2672 else
2673 move_from = i + shift;
2674 if (move_from == msg->sg.end)
2675 break;
2676
2677 msg->sg.data[i] = msg->sg.data[move_from];
2678 msg->sg.data[move_from].length = 0;
2679 msg->sg.data[move_from].page_link = 0;
2680 msg->sg.data[move_from].offset = 0;
2681 sk_msg_iter_var_next(i);
2682 } while (1);
2683
2684 msg->sg.end = msg->sg.end - shift > msg->sg.end ?
2685 msg->sg.end - shift + NR_MSG_FRAG_IDS :
2686 msg->sg.end - shift;
2687 out:
2688 msg->data = sg_virt(&msg->sg.data[first_sge]) + start - offset;
2689 msg->data_end = msg->data + bytes;
2690 return 0;
2691 }
2692
2693 static const struct bpf_func_proto bpf_msg_pull_data_proto = {
2694 .func = bpf_msg_pull_data,
2695 .gpl_only = false,
2696 .ret_type = RET_INTEGER,
2697 .arg1_type = ARG_PTR_TO_CTX,
2698 .arg2_type = ARG_ANYTHING,
2699 .arg3_type = ARG_ANYTHING,
2700 .arg4_type = ARG_ANYTHING,
2701 };
2702
BPF_CALL_4(bpf_msg_push_data,struct sk_msg *,msg,u32,start,u32,len,u64,flags)2703 BPF_CALL_4(bpf_msg_push_data, struct sk_msg *, msg, u32, start,
2704 u32, len, u64, flags)
2705 {
2706 struct scatterlist sge, nsge, nnsge, rsge = {0}, *psge;
2707 u32 new, i = 0, l = 0, space, copy = 0, offset = 0;
2708 u8 *raw, *to, *from;
2709 struct page *page;
2710
2711 if (unlikely(flags))
2712 return -EINVAL;
2713
2714 /* First find the starting scatterlist element */
2715 i = msg->sg.start;
2716 do {
2717 offset += l;
2718 l = sk_msg_elem(msg, i)->length;
2719
2720 if (start < offset + l)
2721 break;
2722 sk_msg_iter_var_next(i);
2723 } while (i != msg->sg.end);
2724
2725 if (start >= offset + l)
2726 return -EINVAL;
2727
2728 space = MAX_MSG_FRAGS - sk_msg_elem_used(msg);
2729
2730 /* If no space available will fallback to copy, we need at
2731 * least one scatterlist elem available to push data into
2732 * when start aligns to the beginning of an element or two
2733 * when it falls inside an element. We handle the start equals
2734 * offset case because its the common case for inserting a
2735 * header.
2736 */
2737 if (!space || (space == 1 && start != offset))
2738 copy = msg->sg.data[i].length;
2739
2740 page = alloc_pages(__GFP_NOWARN | GFP_ATOMIC | __GFP_COMP,
2741 get_order(copy + len));
2742 if (unlikely(!page))
2743 return -ENOMEM;
2744
2745 if (copy) {
2746 int front, back;
2747
2748 raw = page_address(page);
2749
2750 psge = sk_msg_elem(msg, i);
2751 front = start - offset;
2752 back = psge->length - front;
2753 from = sg_virt(psge);
2754
2755 if (front)
2756 memcpy(raw, from, front);
2757
2758 if (back) {
2759 from += front;
2760 to = raw + front + len;
2761
2762 memcpy(to, from, back);
2763 }
2764
2765 put_page(sg_page(psge));
2766 } else if (start - offset) {
2767 psge = sk_msg_elem(msg, i);
2768 rsge = sk_msg_elem_cpy(msg, i);
2769
2770 psge->length = start - offset;
2771 rsge.length -= psge->length;
2772 rsge.offset += start;
2773
2774 sk_msg_iter_var_next(i);
2775 sg_unmark_end(psge);
2776 sg_unmark_end(&rsge);
2777 sk_msg_iter_next(msg, end);
2778 }
2779
2780 /* Slot(s) to place newly allocated data */
2781 new = i;
2782
2783 /* Shift one or two slots as needed */
2784 if (!copy) {
2785 sge = sk_msg_elem_cpy(msg, i);
2786
2787 sk_msg_iter_var_next(i);
2788 sg_unmark_end(&sge);
2789 sk_msg_iter_next(msg, end);
2790
2791 nsge = sk_msg_elem_cpy(msg, i);
2792 if (rsge.length) {
2793 sk_msg_iter_var_next(i);
2794 nnsge = sk_msg_elem_cpy(msg, i);
2795 }
2796
2797 while (i != msg->sg.end) {
2798 msg->sg.data[i] = sge;
2799 sge = nsge;
2800 sk_msg_iter_var_next(i);
2801 if (rsge.length) {
2802 nsge = nnsge;
2803 nnsge = sk_msg_elem_cpy(msg, i);
2804 } else {
2805 nsge = sk_msg_elem_cpy(msg, i);
2806 }
2807 }
2808 }
2809
2810 /* Place newly allocated data buffer */
2811 sk_mem_charge(msg->sk, len);
2812 msg->sg.size += len;
2813 __clear_bit(new, &msg->sg.copy);
2814 sg_set_page(&msg->sg.data[new], page, len + copy, 0);
2815 if (rsge.length) {
2816 get_page(sg_page(&rsge));
2817 sk_msg_iter_var_next(new);
2818 msg->sg.data[new] = rsge;
2819 }
2820
2821 sk_msg_compute_data_pointers(msg);
2822 return 0;
2823 }
2824
2825 static const struct bpf_func_proto bpf_msg_push_data_proto = {
2826 .func = bpf_msg_push_data,
2827 .gpl_only = false,
2828 .ret_type = RET_INTEGER,
2829 .arg1_type = ARG_PTR_TO_CTX,
2830 .arg2_type = ARG_ANYTHING,
2831 .arg3_type = ARG_ANYTHING,
2832 .arg4_type = ARG_ANYTHING,
2833 };
2834
sk_msg_shift_left(struct sk_msg * msg,int i)2835 static void sk_msg_shift_left(struct sk_msg *msg, int i)
2836 {
2837 int prev;
2838
2839 do {
2840 prev = i;
2841 sk_msg_iter_var_next(i);
2842 msg->sg.data[prev] = msg->sg.data[i];
2843 } while (i != msg->sg.end);
2844
2845 sk_msg_iter_prev(msg, end);
2846 }
2847
sk_msg_shift_right(struct sk_msg * msg,int i)2848 static void sk_msg_shift_right(struct sk_msg *msg, int i)
2849 {
2850 struct scatterlist tmp, sge;
2851
2852 sk_msg_iter_next(msg, end);
2853 sge = sk_msg_elem_cpy(msg, i);
2854 sk_msg_iter_var_next(i);
2855 tmp = sk_msg_elem_cpy(msg, i);
2856
2857 while (i != msg->sg.end) {
2858 msg->sg.data[i] = sge;
2859 sk_msg_iter_var_next(i);
2860 sge = tmp;
2861 tmp = sk_msg_elem_cpy(msg, i);
2862 }
2863 }
2864
BPF_CALL_4(bpf_msg_pop_data,struct sk_msg *,msg,u32,start,u32,len,u64,flags)2865 BPF_CALL_4(bpf_msg_pop_data, struct sk_msg *, msg, u32, start,
2866 u32, len, u64, flags)
2867 {
2868 u32 i = 0, l = 0, space, offset = 0;
2869 u64 last = start + len;
2870 int pop;
2871
2872 if (unlikely(flags))
2873 return -EINVAL;
2874
2875 /* First find the starting scatterlist element */
2876 i = msg->sg.start;
2877 do {
2878 offset += l;
2879 l = sk_msg_elem(msg, i)->length;
2880
2881 if (start < offset + l)
2882 break;
2883 sk_msg_iter_var_next(i);
2884 } while (i != msg->sg.end);
2885
2886 /* Bounds checks: start and pop must be inside message */
2887 if (start >= offset + l || last >= msg->sg.size)
2888 return -EINVAL;
2889
2890 space = MAX_MSG_FRAGS - sk_msg_elem_used(msg);
2891
2892 pop = len;
2893 /* --------------| offset
2894 * -| start |-------- len -------|
2895 *
2896 * |----- a ----|-------- pop -------|----- b ----|
2897 * |______________________________________________| length
2898 *
2899 *
2900 * a: region at front of scatter element to save
2901 * b: region at back of scatter element to save when length > A + pop
2902 * pop: region to pop from element, same as input 'pop' here will be
2903 * decremented below per iteration.
2904 *
2905 * Two top-level cases to handle when start != offset, first B is non
2906 * zero and second B is zero corresponding to when a pop includes more
2907 * than one element.
2908 *
2909 * Then if B is non-zero AND there is no space allocate space and
2910 * compact A, B regions into page. If there is space shift ring to
2911 * the rigth free'ing the next element in ring to place B, leaving
2912 * A untouched except to reduce length.
2913 */
2914 if (start != offset) {
2915 struct scatterlist *nsge, *sge = sk_msg_elem(msg, i);
2916 int a = start;
2917 int b = sge->length - pop - a;
2918
2919 sk_msg_iter_var_next(i);
2920
2921 if (pop < sge->length - a) {
2922 if (space) {
2923 sge->length = a;
2924 sk_msg_shift_right(msg, i);
2925 nsge = sk_msg_elem(msg, i);
2926 get_page(sg_page(sge));
2927 sg_set_page(nsge,
2928 sg_page(sge),
2929 b, sge->offset + pop + a);
2930 } else {
2931 struct page *page, *orig;
2932 u8 *to, *from;
2933
2934 page = alloc_pages(__GFP_NOWARN |
2935 __GFP_COMP | GFP_ATOMIC,
2936 get_order(a + b));
2937 if (unlikely(!page))
2938 return -ENOMEM;
2939
2940 sge->length = a;
2941 orig = sg_page(sge);
2942 from = sg_virt(sge);
2943 to = page_address(page);
2944 memcpy(to, from, a);
2945 memcpy(to + a, from + a + pop, b);
2946 sg_set_page(sge, page, a + b, 0);
2947 put_page(orig);
2948 }
2949 pop = 0;
2950 } else if (pop >= sge->length - a) {
2951 pop -= (sge->length - a);
2952 sge->length = a;
2953 }
2954 }
2955
2956 /* From above the current layout _must_ be as follows,
2957 *
2958 * -| offset
2959 * -| start
2960 *
2961 * |---- pop ---|---------------- b ------------|
2962 * |____________________________________________| length
2963 *
2964 * Offset and start of the current msg elem are equal because in the
2965 * previous case we handled offset != start and either consumed the
2966 * entire element and advanced to the next element OR pop == 0.
2967 *
2968 * Two cases to handle here are first pop is less than the length
2969 * leaving some remainder b above. Simply adjust the element's layout
2970 * in this case. Or pop >= length of the element so that b = 0. In this
2971 * case advance to next element decrementing pop.
2972 */
2973 while (pop) {
2974 struct scatterlist *sge = sk_msg_elem(msg, i);
2975
2976 if (pop < sge->length) {
2977 sge->length -= pop;
2978 sge->offset += pop;
2979 pop = 0;
2980 } else {
2981 pop -= sge->length;
2982 sk_msg_shift_left(msg, i);
2983 }
2984 sk_msg_iter_var_next(i);
2985 }
2986
2987 sk_mem_uncharge(msg->sk, len - pop);
2988 msg->sg.size -= (len - pop);
2989 sk_msg_compute_data_pointers(msg);
2990 return 0;
2991 }
2992
2993 static const struct bpf_func_proto bpf_msg_pop_data_proto = {
2994 .func = bpf_msg_pop_data,
2995 .gpl_only = false,
2996 .ret_type = RET_INTEGER,
2997 .arg1_type = ARG_PTR_TO_CTX,
2998 .arg2_type = ARG_ANYTHING,
2999 .arg3_type = ARG_ANYTHING,
3000 .arg4_type = ARG_ANYTHING,
3001 };
3002
3003 #ifdef CONFIG_CGROUP_NET_CLASSID
BPF_CALL_0(bpf_get_cgroup_classid_curr)3004 BPF_CALL_0(bpf_get_cgroup_classid_curr)
3005 {
3006 return __task_get_classid(current);
3007 }
3008
3009 static const struct bpf_func_proto bpf_get_cgroup_classid_curr_proto = {
3010 .func = bpf_get_cgroup_classid_curr,
3011 .gpl_only = false,
3012 .ret_type = RET_INTEGER,
3013 };
3014
BPF_CALL_1(bpf_skb_cgroup_classid,const struct sk_buff *,skb)3015 BPF_CALL_1(bpf_skb_cgroup_classid, const struct sk_buff *, skb)
3016 {
3017 struct sock *sk = skb_to_full_sk(skb);
3018
3019 if (!sk || !sk_fullsock(sk))
3020 return 0;
3021
3022 return sock_cgroup_classid(&sk->sk_cgrp_data);
3023 }
3024
3025 static const struct bpf_func_proto bpf_skb_cgroup_classid_proto = {
3026 .func = bpf_skb_cgroup_classid,
3027 .gpl_only = false,
3028 .ret_type = RET_INTEGER,
3029 .arg1_type = ARG_PTR_TO_CTX,
3030 };
3031 #endif
3032
BPF_CALL_1(bpf_get_cgroup_classid,const struct sk_buff *,skb)3033 BPF_CALL_1(bpf_get_cgroup_classid, const struct sk_buff *, skb)
3034 {
3035 return task_get_classid(skb);
3036 }
3037
3038 static const struct bpf_func_proto bpf_get_cgroup_classid_proto = {
3039 .func = bpf_get_cgroup_classid,
3040 .gpl_only = false,
3041 .ret_type = RET_INTEGER,
3042 .arg1_type = ARG_PTR_TO_CTX,
3043 };
3044
BPF_CALL_1(bpf_get_route_realm,const struct sk_buff *,skb)3045 BPF_CALL_1(bpf_get_route_realm, const struct sk_buff *, skb)
3046 {
3047 return dst_tclassid(skb);
3048 }
3049
3050 static const struct bpf_func_proto bpf_get_route_realm_proto = {
3051 .func = bpf_get_route_realm,
3052 .gpl_only = false,
3053 .ret_type = RET_INTEGER,
3054 .arg1_type = ARG_PTR_TO_CTX,
3055 };
3056
BPF_CALL_1(bpf_get_hash_recalc,struct sk_buff *,skb)3057 BPF_CALL_1(bpf_get_hash_recalc, struct sk_buff *, skb)
3058 {
3059 /* If skb_clear_hash() was called due to mangling, we can
3060 * trigger SW recalculation here. Later access to hash
3061 * can then use the inline skb->hash via context directly
3062 * instead of calling this helper again.
3063 */
3064 return skb_get_hash(skb);
3065 }
3066
3067 static const struct bpf_func_proto bpf_get_hash_recalc_proto = {
3068 .func = bpf_get_hash_recalc,
3069 .gpl_only = false,
3070 .ret_type = RET_INTEGER,
3071 .arg1_type = ARG_PTR_TO_CTX,
3072 };
3073
BPF_CALL_1(bpf_set_hash_invalid,struct sk_buff *,skb)3074 BPF_CALL_1(bpf_set_hash_invalid, struct sk_buff *, skb)
3075 {
3076 /* After all direct packet write, this can be used once for
3077 * triggering a lazy recalc on next skb_get_hash() invocation.
3078 */
3079 skb_clear_hash(skb);
3080 return 0;
3081 }
3082
3083 static const struct bpf_func_proto bpf_set_hash_invalid_proto = {
3084 .func = bpf_set_hash_invalid,
3085 .gpl_only = false,
3086 .ret_type = RET_INTEGER,
3087 .arg1_type = ARG_PTR_TO_CTX,
3088 };
3089
BPF_CALL_2(bpf_set_hash,struct sk_buff *,skb,u32,hash)3090 BPF_CALL_2(bpf_set_hash, struct sk_buff *, skb, u32, hash)
3091 {
3092 /* Set user specified hash as L4(+), so that it gets returned
3093 * on skb_get_hash() call unless BPF prog later on triggers a
3094 * skb_clear_hash().
3095 */
3096 __skb_set_sw_hash(skb, hash, true);
3097 return 0;
3098 }
3099
3100 static const struct bpf_func_proto bpf_set_hash_proto = {
3101 .func = bpf_set_hash,
3102 .gpl_only = false,
3103 .ret_type = RET_INTEGER,
3104 .arg1_type = ARG_PTR_TO_CTX,
3105 .arg2_type = ARG_ANYTHING,
3106 };
3107
BPF_CALL_3(bpf_skb_vlan_push,struct sk_buff *,skb,__be16,vlan_proto,u16,vlan_tci)3108 BPF_CALL_3(bpf_skb_vlan_push, struct sk_buff *, skb, __be16, vlan_proto,
3109 u16, vlan_tci)
3110 {
3111 int ret;
3112
3113 if (unlikely(vlan_proto != htons(ETH_P_8021Q) &&
3114 vlan_proto != htons(ETH_P_8021AD)))
3115 vlan_proto = htons(ETH_P_8021Q);
3116
3117 bpf_push_mac_rcsum(skb);
3118 ret = skb_vlan_push(skb, vlan_proto, vlan_tci);
3119 bpf_pull_mac_rcsum(skb);
3120
3121 bpf_compute_data_pointers(skb);
3122 return ret;
3123 }
3124
3125 static const struct bpf_func_proto bpf_skb_vlan_push_proto = {
3126 .func = bpf_skb_vlan_push,
3127 .gpl_only = false,
3128 .ret_type = RET_INTEGER,
3129 .arg1_type = ARG_PTR_TO_CTX,
3130 .arg2_type = ARG_ANYTHING,
3131 .arg3_type = ARG_ANYTHING,
3132 };
3133
BPF_CALL_1(bpf_skb_vlan_pop,struct sk_buff *,skb)3134 BPF_CALL_1(bpf_skb_vlan_pop, struct sk_buff *, skb)
3135 {
3136 int ret;
3137
3138 bpf_push_mac_rcsum(skb);
3139 ret = skb_vlan_pop(skb);
3140 bpf_pull_mac_rcsum(skb);
3141
3142 bpf_compute_data_pointers(skb);
3143 return ret;
3144 }
3145
3146 static const struct bpf_func_proto bpf_skb_vlan_pop_proto = {
3147 .func = bpf_skb_vlan_pop,
3148 .gpl_only = false,
3149 .ret_type = RET_INTEGER,
3150 .arg1_type = ARG_PTR_TO_CTX,
3151 };
3152
bpf_skb_generic_push(struct sk_buff * skb,u32 off,u32 len)3153 static int bpf_skb_generic_push(struct sk_buff *skb, u32 off, u32 len)
3154 {
3155 /* Caller already did skb_cow() with len as headroom,
3156 * so no need to do it here.
3157 */
3158 skb_push(skb, len);
3159 memmove(skb->data, skb->data + len, off);
3160 memset(skb->data + off, 0, len);
3161
3162 /* No skb_postpush_rcsum(skb, skb->data + off, len)
3163 * needed here as it does not change the skb->csum
3164 * result for checksum complete when summing over
3165 * zeroed blocks.
3166 */
3167 return 0;
3168 }
3169
bpf_skb_generic_pop(struct sk_buff * skb,u32 off,u32 len)3170 static int bpf_skb_generic_pop(struct sk_buff *skb, u32 off, u32 len)
3171 {
3172 /* skb_ensure_writable() is not needed here, as we're
3173 * already working on an uncloned skb.
3174 */
3175 if (unlikely(!pskb_may_pull(skb, off + len)))
3176 return -ENOMEM;
3177
3178 skb_postpull_rcsum(skb, skb->data + off, len);
3179 memmove(skb->data + len, skb->data, off);
3180 __skb_pull(skb, len);
3181
3182 return 0;
3183 }
3184
bpf_skb_net_hdr_push(struct sk_buff * skb,u32 off,u32 len)3185 static int bpf_skb_net_hdr_push(struct sk_buff *skb, u32 off, u32 len)
3186 {
3187 bool trans_same = skb->transport_header == skb->network_header;
3188 int ret;
3189
3190 /* There's no need for __skb_push()/__skb_pull() pair to
3191 * get to the start of the mac header as we're guaranteed
3192 * to always start from here under eBPF.
3193 */
3194 ret = bpf_skb_generic_push(skb, off, len);
3195 if (likely(!ret)) {
3196 skb->mac_header -= len;
3197 skb->network_header -= len;
3198 if (trans_same)
3199 skb->transport_header = skb->network_header;
3200 }
3201
3202 return ret;
3203 }
3204
bpf_skb_net_hdr_pop(struct sk_buff * skb,u32 off,u32 len)3205 static int bpf_skb_net_hdr_pop(struct sk_buff *skb, u32 off, u32 len)
3206 {
3207 bool trans_same = skb->transport_header == skb->network_header;
3208 int ret;
3209
3210 /* Same here, __skb_push()/__skb_pull() pair not needed. */
3211 ret = bpf_skb_generic_pop(skb, off, len);
3212 if (likely(!ret)) {
3213 skb->mac_header += len;
3214 skb->network_header += len;
3215 if (trans_same)
3216 skb->transport_header = skb->network_header;
3217 }
3218
3219 return ret;
3220 }
3221
bpf_skb_proto_4_to_6(struct sk_buff * skb)3222 static int bpf_skb_proto_4_to_6(struct sk_buff *skb)
3223 {
3224 const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr);
3225 u32 off = skb_mac_header_len(skb);
3226 int ret;
3227
3228 ret = skb_cow(skb, len_diff);
3229 if (unlikely(ret < 0))
3230 return ret;
3231
3232 ret = bpf_skb_net_hdr_push(skb, off, len_diff);
3233 if (unlikely(ret < 0))
3234 return ret;
3235
3236 if (skb_is_gso(skb)) {
3237 struct skb_shared_info *shinfo = skb_shinfo(skb);
3238
3239 /* SKB_GSO_TCPV4 needs to be changed into SKB_GSO_TCPV6. */
3240 if (shinfo->gso_type & SKB_GSO_TCPV4) {
3241 shinfo->gso_type &= ~SKB_GSO_TCPV4;
3242 shinfo->gso_type |= SKB_GSO_TCPV6;
3243 }
3244 }
3245
3246 skb->protocol = htons(ETH_P_IPV6);
3247 skb_clear_hash(skb);
3248
3249 return 0;
3250 }
3251
bpf_skb_proto_6_to_4(struct sk_buff * skb)3252 static int bpf_skb_proto_6_to_4(struct sk_buff *skb)
3253 {
3254 const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr);
3255 u32 off = skb_mac_header_len(skb);
3256 int ret;
3257
3258 ret = skb_unclone(skb, GFP_ATOMIC);
3259 if (unlikely(ret < 0))
3260 return ret;
3261
3262 ret = bpf_skb_net_hdr_pop(skb, off, len_diff);
3263 if (unlikely(ret < 0))
3264 return ret;
3265
3266 if (skb_is_gso(skb)) {
3267 struct skb_shared_info *shinfo = skb_shinfo(skb);
3268
3269 /* SKB_GSO_TCPV6 needs to be changed into SKB_GSO_TCPV4. */
3270 if (shinfo->gso_type & SKB_GSO_TCPV6) {
3271 shinfo->gso_type &= ~SKB_GSO_TCPV6;
3272 shinfo->gso_type |= SKB_GSO_TCPV4;
3273 }
3274 }
3275
3276 skb->protocol = htons(ETH_P_IP);
3277 skb_clear_hash(skb);
3278
3279 return 0;
3280 }
3281
bpf_skb_proto_xlat(struct sk_buff * skb,__be16 to_proto)3282 static int bpf_skb_proto_xlat(struct sk_buff *skb, __be16 to_proto)
3283 {
3284 __be16 from_proto = skb->protocol;
3285
3286 if (from_proto == htons(ETH_P_IP) &&
3287 to_proto == htons(ETH_P_IPV6))
3288 return bpf_skb_proto_4_to_6(skb);
3289
3290 if (from_proto == htons(ETH_P_IPV6) &&
3291 to_proto == htons(ETH_P_IP))
3292 return bpf_skb_proto_6_to_4(skb);
3293
3294 return -ENOTSUPP;
3295 }
3296
BPF_CALL_3(bpf_skb_change_proto,struct sk_buff *,skb,__be16,proto,u64,flags)3297 BPF_CALL_3(bpf_skb_change_proto, struct sk_buff *, skb, __be16, proto,
3298 u64, flags)
3299 {
3300 int ret;
3301
3302 if (unlikely(flags))
3303 return -EINVAL;
3304
3305 /* General idea is that this helper does the basic groundwork
3306 * needed for changing the protocol, and eBPF program fills the
3307 * rest through bpf_skb_store_bytes(), bpf_lX_csum_replace()
3308 * and other helpers, rather than passing a raw buffer here.
3309 *
3310 * The rationale is to keep this minimal and without a need to
3311 * deal with raw packet data. F.e. even if we would pass buffers
3312 * here, the program still needs to call the bpf_lX_csum_replace()
3313 * helpers anyway. Plus, this way we keep also separation of
3314 * concerns, since f.e. bpf_skb_store_bytes() should only take
3315 * care of stores.
3316 *
3317 * Currently, additional options and extension header space are
3318 * not supported, but flags register is reserved so we can adapt
3319 * that. For offloads, we mark packet as dodgy, so that headers
3320 * need to be verified first.
3321 */
3322 ret = bpf_skb_proto_xlat(skb, proto);
3323 bpf_compute_data_pointers(skb);
3324 return ret;
3325 }
3326
3327 static const struct bpf_func_proto bpf_skb_change_proto_proto = {
3328 .func = bpf_skb_change_proto,
3329 .gpl_only = false,
3330 .ret_type = RET_INTEGER,
3331 .arg1_type = ARG_PTR_TO_CTX,
3332 .arg2_type = ARG_ANYTHING,
3333 .arg3_type = ARG_ANYTHING,
3334 };
3335
BPF_CALL_2(bpf_skb_change_type,struct sk_buff *,skb,u32,pkt_type)3336 BPF_CALL_2(bpf_skb_change_type, struct sk_buff *, skb, u32, pkt_type)
3337 {
3338 /* We only allow a restricted subset to be changed for now. */
3339 if (unlikely(!skb_pkt_type_ok(skb->pkt_type) ||
3340 !skb_pkt_type_ok(pkt_type)))
3341 return -EINVAL;
3342
3343 skb->pkt_type = pkt_type;
3344 return 0;
3345 }
3346
3347 static const struct bpf_func_proto bpf_skb_change_type_proto = {
3348 .func = bpf_skb_change_type,
3349 .gpl_only = false,
3350 .ret_type = RET_INTEGER,
3351 .arg1_type = ARG_PTR_TO_CTX,
3352 .arg2_type = ARG_ANYTHING,
3353 };
3354
bpf_skb_net_base_len(const struct sk_buff * skb)3355 static u32 bpf_skb_net_base_len(const struct sk_buff *skb)
3356 {
3357 switch (skb->protocol) {
3358 case htons(ETH_P_IP):
3359 return sizeof(struct iphdr);
3360 case htons(ETH_P_IPV6):
3361 return sizeof(struct ipv6hdr);
3362 default:
3363 return ~0U;
3364 }
3365 }
3366
3367 #define BPF_F_ADJ_ROOM_ENCAP_L3_MASK (BPF_F_ADJ_ROOM_ENCAP_L3_IPV4 | \
3368 BPF_F_ADJ_ROOM_ENCAP_L3_IPV6)
3369
3370 #define BPF_F_ADJ_ROOM_MASK (BPF_F_ADJ_ROOM_FIXED_GSO | \
3371 BPF_F_ADJ_ROOM_ENCAP_L3_MASK | \
3372 BPF_F_ADJ_ROOM_ENCAP_L4_GRE | \
3373 BPF_F_ADJ_ROOM_ENCAP_L4_UDP | \
3374 BPF_F_ADJ_ROOM_ENCAP_L2_ETH | \
3375 BPF_F_ADJ_ROOM_ENCAP_L2( \
3376 BPF_ADJ_ROOM_ENCAP_L2_MASK))
3377
bpf_skb_net_grow(struct sk_buff * skb,u32 off,u32 len_diff,u64 flags)3378 static int bpf_skb_net_grow(struct sk_buff *skb, u32 off, u32 len_diff,
3379 u64 flags)
3380 {
3381 u8 inner_mac_len = flags >> BPF_ADJ_ROOM_ENCAP_L2_SHIFT;
3382 bool encap = flags & BPF_F_ADJ_ROOM_ENCAP_L3_MASK;
3383 u16 mac_len = 0, inner_net = 0, inner_trans = 0;
3384 unsigned int gso_type = SKB_GSO_DODGY;
3385 int ret;
3386
3387 if (skb_is_gso(skb) && !skb_is_gso_tcp(skb)) {
3388 /* udp gso_size delineates datagrams, only allow if fixed */
3389 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) ||
3390 !(flags & BPF_F_ADJ_ROOM_FIXED_GSO))
3391 return -ENOTSUPP;
3392 }
3393
3394 ret = skb_cow_head(skb, len_diff);
3395 if (unlikely(ret < 0))
3396 return ret;
3397
3398 if (encap) {
3399 if (skb->protocol != htons(ETH_P_IP) &&
3400 skb->protocol != htons(ETH_P_IPV6))
3401 return -ENOTSUPP;
3402
3403 if (flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV4 &&
3404 flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV6)
3405 return -EINVAL;
3406
3407 if (flags & BPF_F_ADJ_ROOM_ENCAP_L4_GRE &&
3408 flags & BPF_F_ADJ_ROOM_ENCAP_L4_UDP)
3409 return -EINVAL;
3410
3411 if (flags & BPF_F_ADJ_ROOM_ENCAP_L2_ETH &&
3412 inner_mac_len < ETH_HLEN)
3413 return -EINVAL;
3414
3415 if (skb->encapsulation)
3416 return -EALREADY;
3417
3418 mac_len = skb->network_header - skb->mac_header;
3419 inner_net = skb->network_header;
3420 if (inner_mac_len > len_diff)
3421 return -EINVAL;
3422 inner_trans = skb->transport_header;
3423 }
3424
3425 ret = bpf_skb_net_hdr_push(skb, off, len_diff);
3426 if (unlikely(ret < 0))
3427 return ret;
3428
3429 if (encap) {
3430 skb->inner_mac_header = inner_net - inner_mac_len;
3431 skb->inner_network_header = inner_net;
3432 skb->inner_transport_header = inner_trans;
3433
3434 if (flags & BPF_F_ADJ_ROOM_ENCAP_L2_ETH)
3435 skb_set_inner_protocol(skb, htons(ETH_P_TEB));
3436 else
3437 skb_set_inner_protocol(skb, skb->protocol);
3438
3439 skb->encapsulation = 1;
3440 skb_set_network_header(skb, mac_len);
3441
3442 if (flags & BPF_F_ADJ_ROOM_ENCAP_L4_UDP)
3443 gso_type |= SKB_GSO_UDP_TUNNEL;
3444 else if (flags & BPF_F_ADJ_ROOM_ENCAP_L4_GRE)
3445 gso_type |= SKB_GSO_GRE;
3446 else if (flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV6)
3447 gso_type |= SKB_GSO_IPXIP6;
3448 else if (flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV4)
3449 gso_type |= SKB_GSO_IPXIP4;
3450
3451 if (flags & BPF_F_ADJ_ROOM_ENCAP_L4_GRE ||
3452 flags & BPF_F_ADJ_ROOM_ENCAP_L4_UDP) {
3453 int nh_len = flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV6 ?
3454 sizeof(struct ipv6hdr) :
3455 sizeof(struct iphdr);
3456
3457 skb_set_transport_header(skb, mac_len + nh_len);
3458 }
3459
3460 /* Match skb->protocol to new outer l3 protocol */
3461 if (skb->protocol == htons(ETH_P_IP) &&
3462 flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV6)
3463 skb->protocol = htons(ETH_P_IPV6);
3464 else if (skb->protocol == htons(ETH_P_IPV6) &&
3465 flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV4)
3466 skb->protocol = htons(ETH_P_IP);
3467 }
3468
3469 if (skb_is_gso(skb)) {
3470 struct skb_shared_info *shinfo = skb_shinfo(skb);
3471
3472 /* Due to header grow, MSS needs to be downgraded. */
3473 if (!(flags & BPF_F_ADJ_ROOM_FIXED_GSO))
3474 skb_decrease_gso_size(shinfo, len_diff);
3475
3476 /* Header must be checked, and gso_segs recomputed. */
3477 shinfo->gso_type |= gso_type;
3478 shinfo->gso_segs = 0;
3479 }
3480
3481 return 0;
3482 }
3483
bpf_skb_net_shrink(struct sk_buff * skb,u32 off,u32 len_diff,u64 flags)3484 static int bpf_skb_net_shrink(struct sk_buff *skb, u32 off, u32 len_diff,
3485 u64 flags)
3486 {
3487 int ret;
3488
3489 if (unlikely(flags & ~(BPF_F_ADJ_ROOM_FIXED_GSO |
3490 BPF_F_ADJ_ROOM_NO_CSUM_RESET)))
3491 return -EINVAL;
3492
3493 if (skb_is_gso(skb) && !skb_is_gso_tcp(skb)) {
3494 /* udp gso_size delineates datagrams, only allow if fixed */
3495 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) ||
3496 !(flags & BPF_F_ADJ_ROOM_FIXED_GSO))
3497 return -ENOTSUPP;
3498 }
3499
3500 ret = skb_unclone(skb, GFP_ATOMIC);
3501 if (unlikely(ret < 0))
3502 return ret;
3503
3504 ret = bpf_skb_net_hdr_pop(skb, off, len_diff);
3505 if (unlikely(ret < 0))
3506 return ret;
3507
3508 if (skb_is_gso(skb)) {
3509 struct skb_shared_info *shinfo = skb_shinfo(skb);
3510
3511 /* Due to header shrink, MSS can be upgraded. */
3512 if (!(flags & BPF_F_ADJ_ROOM_FIXED_GSO))
3513 skb_increase_gso_size(shinfo, len_diff);
3514
3515 /* Header must be checked, and gso_segs recomputed. */
3516 shinfo->gso_type |= SKB_GSO_DODGY;
3517 shinfo->gso_segs = 0;
3518 }
3519
3520 return 0;
3521 }
3522
3523 #define BPF_SKB_MAX_LEN SKB_MAX_ALLOC
3524
BPF_CALL_4(sk_skb_adjust_room,struct sk_buff *,skb,s32,len_diff,u32,mode,u64,flags)3525 BPF_CALL_4(sk_skb_adjust_room, struct sk_buff *, skb, s32, len_diff,
3526 u32, mode, u64, flags)
3527 {
3528 u32 len_diff_abs = abs(len_diff);
3529 bool shrink = len_diff < 0;
3530 int ret = 0;
3531
3532 if (unlikely(flags || mode))
3533 return -EINVAL;
3534 if (unlikely(len_diff_abs > 0xfffU))
3535 return -EFAULT;
3536
3537 if (!shrink) {
3538 ret = skb_cow(skb, len_diff);
3539 if (unlikely(ret < 0))
3540 return ret;
3541 __skb_push(skb, len_diff_abs);
3542 memset(skb->data, 0, len_diff_abs);
3543 } else {
3544 if (unlikely(!pskb_may_pull(skb, len_diff_abs)))
3545 return -ENOMEM;
3546 __skb_pull(skb, len_diff_abs);
3547 }
3548 if (tls_sw_has_ctx_rx(skb->sk)) {
3549 struct strp_msg *rxm = strp_msg(skb);
3550
3551 rxm->full_len += len_diff;
3552 }
3553 return ret;
3554 }
3555
3556 static const struct bpf_func_proto sk_skb_adjust_room_proto = {
3557 .func = sk_skb_adjust_room,
3558 .gpl_only = false,
3559 .ret_type = RET_INTEGER,
3560 .arg1_type = ARG_PTR_TO_CTX,
3561 .arg2_type = ARG_ANYTHING,
3562 .arg3_type = ARG_ANYTHING,
3563 .arg4_type = ARG_ANYTHING,
3564 };
3565
BPF_CALL_4(bpf_skb_adjust_room,struct sk_buff *,skb,s32,len_diff,u32,mode,u64,flags)3566 BPF_CALL_4(bpf_skb_adjust_room, struct sk_buff *, skb, s32, len_diff,
3567 u32, mode, u64, flags)
3568 {
3569 u32 len_cur, len_diff_abs = abs(len_diff);
3570 u32 len_min = bpf_skb_net_base_len(skb);
3571 u32 len_max = BPF_SKB_MAX_LEN;
3572 __be16 proto = skb->protocol;
3573 bool shrink = len_diff < 0;
3574 u32 off;
3575 int ret;
3576
3577 if (unlikely(flags & ~(BPF_F_ADJ_ROOM_MASK |
3578 BPF_F_ADJ_ROOM_NO_CSUM_RESET)))
3579 return -EINVAL;
3580 if (unlikely(len_diff_abs > 0xfffU))
3581 return -EFAULT;
3582 if (unlikely(proto != htons(ETH_P_IP) &&
3583 proto != htons(ETH_P_IPV6)))
3584 return -ENOTSUPP;
3585
3586 off = skb_mac_header_len(skb);
3587 switch (mode) {
3588 case BPF_ADJ_ROOM_NET:
3589 off += bpf_skb_net_base_len(skb);
3590 break;
3591 case BPF_ADJ_ROOM_MAC:
3592 break;
3593 default:
3594 return -ENOTSUPP;
3595 }
3596
3597 len_cur = skb->len - skb_network_offset(skb);
3598 if ((shrink && (len_diff_abs >= len_cur ||
3599 len_cur - len_diff_abs < len_min)) ||
3600 (!shrink && (skb->len + len_diff_abs > len_max &&
3601 !skb_is_gso(skb))))
3602 return -ENOTSUPP;
3603
3604 ret = shrink ? bpf_skb_net_shrink(skb, off, len_diff_abs, flags) :
3605 bpf_skb_net_grow(skb, off, len_diff_abs, flags);
3606 if (!ret && !(flags & BPF_F_ADJ_ROOM_NO_CSUM_RESET))
3607 __skb_reset_checksum_unnecessary(skb);
3608
3609 bpf_compute_data_pointers(skb);
3610 return ret;
3611 }
3612
3613 static const struct bpf_func_proto bpf_skb_adjust_room_proto = {
3614 .func = bpf_skb_adjust_room,
3615 .gpl_only = false,
3616 .ret_type = RET_INTEGER,
3617 .arg1_type = ARG_PTR_TO_CTX,
3618 .arg2_type = ARG_ANYTHING,
3619 .arg3_type = ARG_ANYTHING,
3620 .arg4_type = ARG_ANYTHING,
3621 };
3622
__bpf_skb_min_len(const struct sk_buff * skb)3623 static u32 __bpf_skb_min_len(const struct sk_buff *skb)
3624 {
3625 u32 min_len = skb_network_offset(skb);
3626
3627 if (skb_transport_header_was_set(skb))
3628 min_len = skb_transport_offset(skb);
3629 if (skb->ip_summed == CHECKSUM_PARTIAL)
3630 min_len = skb_checksum_start_offset(skb) +
3631 skb->csum_offset + sizeof(__sum16);
3632 return min_len;
3633 }
3634
bpf_skb_grow_rcsum(struct sk_buff * skb,unsigned int new_len)3635 static int bpf_skb_grow_rcsum(struct sk_buff *skb, unsigned int new_len)
3636 {
3637 unsigned int old_len = skb->len;
3638 int ret;
3639
3640 ret = __skb_grow_rcsum(skb, new_len);
3641 if (!ret)
3642 memset(skb->data + old_len, 0, new_len - old_len);
3643 return ret;
3644 }
3645
bpf_skb_trim_rcsum(struct sk_buff * skb,unsigned int new_len)3646 static int bpf_skb_trim_rcsum(struct sk_buff *skb, unsigned int new_len)
3647 {
3648 return __skb_trim_rcsum(skb, new_len);
3649 }
3650
__bpf_skb_change_tail(struct sk_buff * skb,u32 new_len,u64 flags)3651 static inline int __bpf_skb_change_tail(struct sk_buff *skb, u32 new_len,
3652 u64 flags)
3653 {
3654 u32 max_len = BPF_SKB_MAX_LEN;
3655 u32 min_len = __bpf_skb_min_len(skb);
3656 int ret;
3657
3658 if (unlikely(flags || new_len > max_len || new_len < min_len))
3659 return -EINVAL;
3660 if (skb->encapsulation)
3661 return -ENOTSUPP;
3662
3663 /* The basic idea of this helper is that it's performing the
3664 * needed work to either grow or trim an skb, and eBPF program
3665 * rewrites the rest via helpers like bpf_skb_store_bytes(),
3666 * bpf_lX_csum_replace() and others rather than passing a raw
3667 * buffer here. This one is a slow path helper and intended
3668 * for replies with control messages.
3669 *
3670 * Like in bpf_skb_change_proto(), we want to keep this rather
3671 * minimal and without protocol specifics so that we are able
3672 * to separate concerns as in bpf_skb_store_bytes() should only
3673 * be the one responsible for writing buffers.
3674 *
3675 * It's really expected to be a slow path operation here for
3676 * control message replies, so we're implicitly linearizing,
3677 * uncloning and drop offloads from the skb by this.
3678 */
3679 ret = __bpf_try_make_writable(skb, skb->len);
3680 if (!ret) {
3681 if (new_len > skb->len)
3682 ret = bpf_skb_grow_rcsum(skb, new_len);
3683 else if (new_len < skb->len)
3684 ret = bpf_skb_trim_rcsum(skb, new_len);
3685 if (!ret && skb_is_gso(skb))
3686 skb_gso_reset(skb);
3687 }
3688 return ret;
3689 }
3690
BPF_CALL_3(bpf_skb_change_tail,struct sk_buff *,skb,u32,new_len,u64,flags)3691 BPF_CALL_3(bpf_skb_change_tail, struct sk_buff *, skb, u32, new_len,
3692 u64, flags)
3693 {
3694 int ret = __bpf_skb_change_tail(skb, new_len, flags);
3695
3696 bpf_compute_data_pointers(skb);
3697 return ret;
3698 }
3699
3700 static const struct bpf_func_proto bpf_skb_change_tail_proto = {
3701 .func = bpf_skb_change_tail,
3702 .gpl_only = false,
3703 .ret_type = RET_INTEGER,
3704 .arg1_type = ARG_PTR_TO_CTX,
3705 .arg2_type = ARG_ANYTHING,
3706 .arg3_type = ARG_ANYTHING,
3707 };
3708
BPF_CALL_3(sk_skb_change_tail,struct sk_buff *,skb,u32,new_len,u64,flags)3709 BPF_CALL_3(sk_skb_change_tail, struct sk_buff *, skb, u32, new_len,
3710 u64, flags)
3711 {
3712 return __bpf_skb_change_tail(skb, new_len, flags);
3713 }
3714
3715 static const struct bpf_func_proto sk_skb_change_tail_proto = {
3716 .func = sk_skb_change_tail,
3717 .gpl_only = false,
3718 .ret_type = RET_INTEGER,
3719 .arg1_type = ARG_PTR_TO_CTX,
3720 .arg2_type = ARG_ANYTHING,
3721 .arg3_type = ARG_ANYTHING,
3722 };
3723
__bpf_skb_change_head(struct sk_buff * skb,u32 head_room,u64 flags)3724 static inline int __bpf_skb_change_head(struct sk_buff *skb, u32 head_room,
3725 u64 flags)
3726 {
3727 u32 max_len = BPF_SKB_MAX_LEN;
3728 u32 new_len = skb->len + head_room;
3729 int ret;
3730
3731 if (unlikely(flags || (!skb_is_gso(skb) && new_len > max_len) ||
3732 new_len < skb->len))
3733 return -EINVAL;
3734
3735 ret = skb_cow(skb, head_room);
3736 if (likely(!ret)) {
3737 /* Idea for this helper is that we currently only
3738 * allow to expand on mac header. This means that
3739 * skb->protocol network header, etc, stay as is.
3740 * Compared to bpf_skb_change_tail(), we're more
3741 * flexible due to not needing to linearize or
3742 * reset GSO. Intention for this helper is to be
3743 * used by an L3 skb that needs to push mac header
3744 * for redirection into L2 device.
3745 */
3746 __skb_push(skb, head_room);
3747 memset(skb->data, 0, head_room);
3748 skb_reset_mac_header(skb);
3749 skb_reset_mac_len(skb);
3750 }
3751
3752 return ret;
3753 }
3754
BPF_CALL_3(bpf_skb_change_head,struct sk_buff *,skb,u32,head_room,u64,flags)3755 BPF_CALL_3(bpf_skb_change_head, struct sk_buff *, skb, u32, head_room,
3756 u64, flags)
3757 {
3758 int ret = __bpf_skb_change_head(skb, head_room, flags);
3759
3760 bpf_compute_data_pointers(skb);
3761 return ret;
3762 }
3763
3764 static const struct bpf_func_proto bpf_skb_change_head_proto = {
3765 .func = bpf_skb_change_head,
3766 .gpl_only = false,
3767 .ret_type = RET_INTEGER,
3768 .arg1_type = ARG_PTR_TO_CTX,
3769 .arg2_type = ARG_ANYTHING,
3770 .arg3_type = ARG_ANYTHING,
3771 };
3772
BPF_CALL_3(sk_skb_change_head,struct sk_buff *,skb,u32,head_room,u64,flags)3773 BPF_CALL_3(sk_skb_change_head, struct sk_buff *, skb, u32, head_room,
3774 u64, flags)
3775 {
3776 return __bpf_skb_change_head(skb, head_room, flags);
3777 }
3778
3779 static const struct bpf_func_proto sk_skb_change_head_proto = {
3780 .func = sk_skb_change_head,
3781 .gpl_only = false,
3782 .ret_type = RET_INTEGER,
3783 .arg1_type = ARG_PTR_TO_CTX,
3784 .arg2_type = ARG_ANYTHING,
3785 .arg3_type = ARG_ANYTHING,
3786 };
xdp_get_metalen(const struct xdp_buff * xdp)3787 static unsigned long xdp_get_metalen(const struct xdp_buff *xdp)
3788 {
3789 return xdp_data_meta_unsupported(xdp) ? 0 :
3790 xdp->data - xdp->data_meta;
3791 }
3792
BPF_CALL_2(bpf_xdp_adjust_head,struct xdp_buff *,xdp,int,offset)3793 BPF_CALL_2(bpf_xdp_adjust_head, struct xdp_buff *, xdp, int, offset)
3794 {
3795 void *xdp_frame_end = xdp->data_hard_start + sizeof(struct xdp_frame);
3796 unsigned long metalen = xdp_get_metalen(xdp);
3797 void *data_start = xdp_frame_end + metalen;
3798 void *data = xdp->data + offset;
3799
3800 if (unlikely(data < data_start ||
3801 data > xdp->data_end - ETH_HLEN))
3802 return -EINVAL;
3803
3804 if (metalen)
3805 memmove(xdp->data_meta + offset,
3806 xdp->data_meta, metalen);
3807 xdp->data_meta += offset;
3808 xdp->data = data;
3809
3810 return 0;
3811 }
3812
3813 static const struct bpf_func_proto bpf_xdp_adjust_head_proto = {
3814 .func = bpf_xdp_adjust_head,
3815 .gpl_only = false,
3816 .ret_type = RET_INTEGER,
3817 .arg1_type = ARG_PTR_TO_CTX,
3818 .arg2_type = ARG_ANYTHING,
3819 };
3820
BPF_CALL_2(bpf_xdp_adjust_tail,struct xdp_buff *,xdp,int,offset)3821 BPF_CALL_2(bpf_xdp_adjust_tail, struct xdp_buff *, xdp, int, offset)
3822 {
3823 void *data_hard_end = xdp_data_hard_end(xdp); /* use xdp->frame_sz */
3824 void *data_end = xdp->data_end + offset;
3825
3826 /* Notice that xdp_data_hard_end have reserved some tailroom */
3827 if (unlikely(data_end > data_hard_end))
3828 return -EINVAL;
3829
3830 /* ALL drivers MUST init xdp->frame_sz, chicken check below */
3831 if (unlikely(xdp->frame_sz > PAGE_SIZE)) {
3832 WARN_ONCE(1, "Too BIG xdp->frame_sz = %d\n", xdp->frame_sz);
3833 return -EINVAL;
3834 }
3835
3836 if (unlikely(data_end < xdp->data + ETH_HLEN))
3837 return -EINVAL;
3838
3839 /* Clear memory area on grow, can contain uninit kernel memory */
3840 if (offset > 0)
3841 memset(xdp->data_end, 0, offset);
3842
3843 xdp->data_end = data_end;
3844
3845 return 0;
3846 }
3847
3848 static const struct bpf_func_proto bpf_xdp_adjust_tail_proto = {
3849 .func = bpf_xdp_adjust_tail,
3850 .gpl_only = false,
3851 .ret_type = RET_INTEGER,
3852 .arg1_type = ARG_PTR_TO_CTX,
3853 .arg2_type = ARG_ANYTHING,
3854 };
3855
BPF_CALL_2(bpf_xdp_adjust_meta,struct xdp_buff *,xdp,int,offset)3856 BPF_CALL_2(bpf_xdp_adjust_meta, struct xdp_buff *, xdp, int, offset)
3857 {
3858 void *xdp_frame_end = xdp->data_hard_start + sizeof(struct xdp_frame);
3859 void *meta = xdp->data_meta + offset;
3860 unsigned long metalen = xdp->data - meta;
3861
3862 if (xdp_data_meta_unsupported(xdp))
3863 return -ENOTSUPP;
3864 if (unlikely(meta < xdp_frame_end ||
3865 meta > xdp->data))
3866 return -EINVAL;
3867 if (unlikely(xdp_metalen_invalid(metalen)))
3868 return -EACCES;
3869
3870 xdp->data_meta = meta;
3871
3872 return 0;
3873 }
3874
3875 static const struct bpf_func_proto bpf_xdp_adjust_meta_proto = {
3876 .func = bpf_xdp_adjust_meta,
3877 .gpl_only = false,
3878 .ret_type = RET_INTEGER,
3879 .arg1_type = ARG_PTR_TO_CTX,
3880 .arg2_type = ARG_ANYTHING,
3881 };
3882
3883 /* XDP_REDIRECT works by a three-step process, implemented in the functions
3884 * below:
3885 *
3886 * 1. The bpf_redirect() and bpf_redirect_map() helpers will lookup the target
3887 * of the redirect and store it (along with some other metadata) in a per-CPU
3888 * struct bpf_redirect_info.
3889 *
3890 * 2. When the program returns the XDP_REDIRECT return code, the driver will
3891 * call xdp_do_redirect() which will use the information in struct
3892 * bpf_redirect_info to actually enqueue the frame into a map type-specific
3893 * bulk queue structure.
3894 *
3895 * 3. Before exiting its NAPI poll loop, the driver will call xdp_do_flush(),
3896 * which will flush all the different bulk queues, thus completing the
3897 * redirect.
3898 *
3899 * Pointers to the map entries will be kept around for this whole sequence of
3900 * steps, protected by RCU. However, there is no top-level rcu_read_lock() in
3901 * the core code; instead, the RCU protection relies on everything happening
3902 * inside a single NAPI poll sequence, which means it's between a pair of calls
3903 * to local_bh_disable()/local_bh_enable().
3904 *
3905 * The map entries are marked as __rcu and the map code makes sure to
3906 * dereference those pointers with rcu_dereference_check() in a way that works
3907 * for both sections that to hold an rcu_read_lock() and sections that are
3908 * called from NAPI without a separate rcu_read_lock(). The code below does not
3909 * use RCU annotations, but relies on those in the map code.
3910 */
xdp_do_flush(void)3911 void xdp_do_flush(void)
3912 {
3913 __dev_flush();
3914 __cpu_map_flush();
3915 __xsk_map_flush();
3916 }
3917 EXPORT_SYMBOL_GPL(xdp_do_flush);
3918
bpf_clear_redirect_map(struct bpf_map * map)3919 void bpf_clear_redirect_map(struct bpf_map *map)
3920 {
3921 struct bpf_redirect_info *ri;
3922 int cpu;
3923
3924 for_each_possible_cpu(cpu) {
3925 ri = per_cpu_ptr(&bpf_redirect_info, cpu);
3926 /* Avoid polluting remote cacheline due to writes if
3927 * not needed. Once we pass this test, we need the
3928 * cmpxchg() to make sure it hasn't been changed in
3929 * the meantime by remote CPU.
3930 */
3931 if (unlikely(READ_ONCE(ri->map) == map))
3932 cmpxchg(&ri->map, map, NULL);
3933 }
3934 }
3935
3936 DEFINE_STATIC_KEY_FALSE(bpf_master_redirect_enabled_key);
3937 EXPORT_SYMBOL_GPL(bpf_master_redirect_enabled_key);
3938
xdp_master_redirect(struct xdp_buff * xdp)3939 u32 xdp_master_redirect(struct xdp_buff *xdp)
3940 {
3941 struct net_device *master, *slave;
3942 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
3943
3944 master = netdev_master_upper_dev_get_rcu(xdp->rxq->dev);
3945 slave = master->netdev_ops->ndo_xdp_get_xmit_slave(master, xdp);
3946 if (slave && slave != xdp->rxq->dev) {
3947 /* The target device is different from the receiving device, so
3948 * redirect it to the new device.
3949 * Using XDP_REDIRECT gets the correct behaviour from XDP enabled
3950 * drivers to unmap the packet from their rx ring.
3951 */
3952 ri->tgt_index = slave->ifindex;
3953 ri->map_id = INT_MAX;
3954 ri->map_type = BPF_MAP_TYPE_UNSPEC;
3955 return XDP_REDIRECT;
3956 }
3957 return XDP_TX;
3958 }
3959 EXPORT_SYMBOL_GPL(xdp_master_redirect);
3960
xdp_do_redirect(struct net_device * dev,struct xdp_buff * xdp,struct bpf_prog * xdp_prog)3961 int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp,
3962 struct bpf_prog *xdp_prog)
3963 {
3964 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
3965 enum bpf_map_type map_type = ri->map_type;
3966 void *fwd = ri->tgt_value;
3967 u32 map_id = ri->map_id;
3968 struct bpf_map *map;
3969 int err;
3970
3971 ri->map_id = 0; /* Valid map id idr range: [1,INT_MAX[ */
3972 ri->map_type = BPF_MAP_TYPE_UNSPEC;
3973
3974 switch (map_type) {
3975 case BPF_MAP_TYPE_DEVMAP:
3976 fallthrough;
3977 case BPF_MAP_TYPE_DEVMAP_HASH:
3978 map = READ_ONCE(ri->map);
3979 if (unlikely(map)) {
3980 WRITE_ONCE(ri->map, NULL);
3981 err = dev_map_enqueue_multi(xdp, dev, map,
3982 ri->flags & BPF_F_EXCLUDE_INGRESS);
3983 } else {
3984 err = dev_map_enqueue(fwd, xdp, dev);
3985 }
3986 break;
3987 case BPF_MAP_TYPE_CPUMAP:
3988 err = cpu_map_enqueue(fwd, xdp, dev);
3989 break;
3990 case BPF_MAP_TYPE_XSKMAP:
3991 err = __xsk_map_redirect(fwd, xdp);
3992 break;
3993 case BPF_MAP_TYPE_UNSPEC:
3994 if (map_id == INT_MAX) {
3995 fwd = dev_get_by_index_rcu(dev_net(dev), ri->tgt_index);
3996 if (unlikely(!fwd)) {
3997 err = -EINVAL;
3998 break;
3999 }
4000 err = dev_xdp_enqueue(fwd, xdp, dev);
4001 break;
4002 }
4003 fallthrough;
4004 default:
4005 err = -EBADRQC;
4006 }
4007
4008 if (unlikely(err))
4009 goto err;
4010
4011 _trace_xdp_redirect_map(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index);
4012 return 0;
4013 err:
4014 _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index, err);
4015 return err;
4016 }
4017 EXPORT_SYMBOL_GPL(xdp_do_redirect);
4018
xdp_do_generic_redirect_map(struct net_device * dev,struct sk_buff * skb,struct xdp_buff * xdp,struct bpf_prog * xdp_prog,void * fwd,enum bpf_map_type map_type,u32 map_id)4019 static int xdp_do_generic_redirect_map(struct net_device *dev,
4020 struct sk_buff *skb,
4021 struct xdp_buff *xdp,
4022 struct bpf_prog *xdp_prog,
4023 void *fwd,
4024 enum bpf_map_type map_type, u32 map_id)
4025 {
4026 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
4027 struct bpf_map *map;
4028 int err;
4029
4030 switch (map_type) {
4031 case BPF_MAP_TYPE_DEVMAP:
4032 fallthrough;
4033 case BPF_MAP_TYPE_DEVMAP_HASH:
4034 map = READ_ONCE(ri->map);
4035 if (unlikely(map)) {
4036 WRITE_ONCE(ri->map, NULL);
4037 err = dev_map_redirect_multi(dev, skb, xdp_prog, map,
4038 ri->flags & BPF_F_EXCLUDE_INGRESS);
4039 } else {
4040 err = dev_map_generic_redirect(fwd, skb, xdp_prog);
4041 }
4042 if (unlikely(err))
4043 goto err;
4044 break;
4045 case BPF_MAP_TYPE_XSKMAP:
4046 err = xsk_generic_rcv(fwd, xdp);
4047 if (err)
4048 goto err;
4049 consume_skb(skb);
4050 break;
4051 case BPF_MAP_TYPE_CPUMAP:
4052 err = cpu_map_generic_redirect(fwd, skb);
4053 if (unlikely(err))
4054 goto err;
4055 break;
4056 default:
4057 err = -EBADRQC;
4058 goto err;
4059 }
4060
4061 _trace_xdp_redirect_map(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index);
4062 return 0;
4063 err:
4064 _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index, err);
4065 return err;
4066 }
4067
xdp_do_generic_redirect(struct net_device * dev,struct sk_buff * skb,struct xdp_buff * xdp,struct bpf_prog * xdp_prog)4068 int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb,
4069 struct xdp_buff *xdp, struct bpf_prog *xdp_prog)
4070 {
4071 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
4072 enum bpf_map_type map_type = ri->map_type;
4073 void *fwd = ri->tgt_value;
4074 u32 map_id = ri->map_id;
4075 int err;
4076
4077 ri->map_id = 0; /* Valid map id idr range: [1,INT_MAX[ */
4078 ri->map_type = BPF_MAP_TYPE_UNSPEC;
4079
4080 if (map_type == BPF_MAP_TYPE_UNSPEC && map_id == INT_MAX) {
4081 fwd = dev_get_by_index_rcu(dev_net(dev), ri->tgt_index);
4082 if (unlikely(!fwd)) {
4083 err = -EINVAL;
4084 goto err;
4085 }
4086
4087 err = xdp_ok_fwd_dev(fwd, skb->len);
4088 if (unlikely(err))
4089 goto err;
4090
4091 skb->dev = fwd;
4092 _trace_xdp_redirect(dev, xdp_prog, ri->tgt_index);
4093 generic_xdp_tx(skb, xdp_prog);
4094 return 0;
4095 }
4096
4097 return xdp_do_generic_redirect_map(dev, skb, xdp, xdp_prog, fwd, map_type, map_id);
4098 err:
4099 _trace_xdp_redirect_err(dev, xdp_prog, ri->tgt_index, err);
4100 return err;
4101 }
4102
BPF_CALL_2(bpf_xdp_redirect,u32,ifindex,u64,flags)4103 BPF_CALL_2(bpf_xdp_redirect, u32, ifindex, u64, flags)
4104 {
4105 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
4106
4107 if (unlikely(flags))
4108 return XDP_ABORTED;
4109
4110 /* NB! Map type UNSPEC and map_id == INT_MAX (never generated
4111 * by map_idr) is used for ifindex based XDP redirect.
4112 */
4113 ri->tgt_index = ifindex;
4114 ri->map_id = INT_MAX;
4115 ri->map_type = BPF_MAP_TYPE_UNSPEC;
4116
4117 return XDP_REDIRECT;
4118 }
4119
4120 static const struct bpf_func_proto bpf_xdp_redirect_proto = {
4121 .func = bpf_xdp_redirect,
4122 .gpl_only = false,
4123 .ret_type = RET_INTEGER,
4124 .arg1_type = ARG_ANYTHING,
4125 .arg2_type = ARG_ANYTHING,
4126 };
4127
BPF_CALL_3(bpf_xdp_redirect_map,struct bpf_map *,map,u32,ifindex,u64,flags)4128 BPF_CALL_3(bpf_xdp_redirect_map, struct bpf_map *, map, u32, ifindex,
4129 u64, flags)
4130 {
4131 return map->ops->map_redirect(map, ifindex, flags);
4132 }
4133
4134 static const struct bpf_func_proto bpf_xdp_redirect_map_proto = {
4135 .func = bpf_xdp_redirect_map,
4136 .gpl_only = false,
4137 .ret_type = RET_INTEGER,
4138 .arg1_type = ARG_CONST_MAP_PTR,
4139 .arg2_type = ARG_ANYTHING,
4140 .arg3_type = ARG_ANYTHING,
4141 };
4142
bpf_skb_copy(void * dst_buff,const void * skb,unsigned long off,unsigned long len)4143 static unsigned long bpf_skb_copy(void *dst_buff, const void *skb,
4144 unsigned long off, unsigned long len)
4145 {
4146 void *ptr = skb_header_pointer(skb, off, len, dst_buff);
4147
4148 if (unlikely(!ptr))
4149 return len;
4150 if (ptr != dst_buff)
4151 memcpy(dst_buff, ptr, len);
4152
4153 return 0;
4154 }
4155
BPF_CALL_5(bpf_skb_event_output,struct sk_buff *,skb,struct bpf_map *,map,u64,flags,void *,meta,u64,meta_size)4156 BPF_CALL_5(bpf_skb_event_output, struct sk_buff *, skb, struct bpf_map *, map,
4157 u64, flags, void *, meta, u64, meta_size)
4158 {
4159 u64 skb_size = (flags & BPF_F_CTXLEN_MASK) >> 32;
4160
4161 if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK)))
4162 return -EINVAL;
4163 if (unlikely(!skb || skb_size > skb->len))
4164 return -EFAULT;
4165
4166 return bpf_event_output(map, flags, meta, meta_size, skb, skb_size,
4167 bpf_skb_copy);
4168 }
4169
4170 static const struct bpf_func_proto bpf_skb_event_output_proto = {
4171 .func = bpf_skb_event_output,
4172 .gpl_only = true,
4173 .ret_type = RET_INTEGER,
4174 .arg1_type = ARG_PTR_TO_CTX,
4175 .arg2_type = ARG_CONST_MAP_PTR,
4176 .arg3_type = ARG_ANYTHING,
4177 .arg4_type = ARG_PTR_TO_MEM,
4178 .arg5_type = ARG_CONST_SIZE_OR_ZERO,
4179 };
4180
4181 BTF_ID_LIST_SINGLE(bpf_skb_output_btf_ids, struct, sk_buff)
4182
4183 const struct bpf_func_proto bpf_skb_output_proto = {
4184 .func = bpf_skb_event_output,
4185 .gpl_only = true,
4186 .ret_type = RET_INTEGER,
4187 .arg1_type = ARG_PTR_TO_BTF_ID,
4188 .arg1_btf_id = &bpf_skb_output_btf_ids[0],
4189 .arg2_type = ARG_CONST_MAP_PTR,
4190 .arg3_type = ARG_ANYTHING,
4191 .arg4_type = ARG_PTR_TO_MEM,
4192 .arg5_type = ARG_CONST_SIZE_OR_ZERO,
4193 };
4194
bpf_tunnel_key_af(u64 flags)4195 static unsigned short bpf_tunnel_key_af(u64 flags)
4196 {
4197 return flags & BPF_F_TUNINFO_IPV6 ? AF_INET6 : AF_INET;
4198 }
4199
BPF_CALL_4(bpf_skb_get_tunnel_key,struct sk_buff *,skb,struct bpf_tunnel_key *,to,u32,size,u64,flags)4200 BPF_CALL_4(bpf_skb_get_tunnel_key, struct sk_buff *, skb, struct bpf_tunnel_key *, to,
4201 u32, size, u64, flags)
4202 {
4203 const struct ip_tunnel_info *info = skb_tunnel_info(skb);
4204 u8 compat[sizeof(struct bpf_tunnel_key)];
4205 void *to_orig = to;
4206 int err;
4207
4208 if (unlikely(!info || (flags & ~(BPF_F_TUNINFO_IPV6)))) {
4209 err = -EINVAL;
4210 goto err_clear;
4211 }
4212 if (ip_tunnel_info_af(info) != bpf_tunnel_key_af(flags)) {
4213 err = -EPROTO;
4214 goto err_clear;
4215 }
4216 if (unlikely(size != sizeof(struct bpf_tunnel_key))) {
4217 err = -EINVAL;
4218 switch (size) {
4219 case offsetof(struct bpf_tunnel_key, tunnel_label):
4220 case offsetof(struct bpf_tunnel_key, tunnel_ext):
4221 goto set_compat;
4222 case offsetof(struct bpf_tunnel_key, remote_ipv6[1]):
4223 /* Fixup deprecated structure layouts here, so we have
4224 * a common path later on.
4225 */
4226 if (ip_tunnel_info_af(info) != AF_INET)
4227 goto err_clear;
4228 set_compat:
4229 to = (struct bpf_tunnel_key *)compat;
4230 break;
4231 default:
4232 goto err_clear;
4233 }
4234 }
4235
4236 to->tunnel_id = be64_to_cpu(info->key.tun_id);
4237 to->tunnel_tos = info->key.tos;
4238 to->tunnel_ttl = info->key.ttl;
4239 to->tunnel_ext = 0;
4240
4241 if (flags & BPF_F_TUNINFO_IPV6) {
4242 memcpy(to->remote_ipv6, &info->key.u.ipv6.src,
4243 sizeof(to->remote_ipv6));
4244 to->tunnel_label = be32_to_cpu(info->key.label);
4245 } else {
4246 to->remote_ipv4 = be32_to_cpu(info->key.u.ipv4.src);
4247 memset(&to->remote_ipv6[1], 0, sizeof(__u32) * 3);
4248 to->tunnel_label = 0;
4249 }
4250
4251 if (unlikely(size != sizeof(struct bpf_tunnel_key)))
4252 memcpy(to_orig, to, size);
4253
4254 return 0;
4255 err_clear:
4256 memset(to_orig, 0, size);
4257 return err;
4258 }
4259
4260 static const struct bpf_func_proto bpf_skb_get_tunnel_key_proto = {
4261 .func = bpf_skb_get_tunnel_key,
4262 .gpl_only = false,
4263 .ret_type = RET_INTEGER,
4264 .arg1_type = ARG_PTR_TO_CTX,
4265 .arg2_type = ARG_PTR_TO_UNINIT_MEM,
4266 .arg3_type = ARG_CONST_SIZE,
4267 .arg4_type = ARG_ANYTHING,
4268 };
4269
BPF_CALL_3(bpf_skb_get_tunnel_opt,struct sk_buff *,skb,u8 *,to,u32,size)4270 BPF_CALL_3(bpf_skb_get_tunnel_opt, struct sk_buff *, skb, u8 *, to, u32, size)
4271 {
4272 const struct ip_tunnel_info *info = skb_tunnel_info(skb);
4273 int err;
4274
4275 if (unlikely(!info ||
4276 !(info->key.tun_flags & TUNNEL_OPTIONS_PRESENT))) {
4277 err = -ENOENT;
4278 goto err_clear;
4279 }
4280 if (unlikely(size < info->options_len)) {
4281 err = -ENOMEM;
4282 goto err_clear;
4283 }
4284
4285 ip_tunnel_info_opts_get(to, info);
4286 if (size > info->options_len)
4287 memset(to + info->options_len, 0, size - info->options_len);
4288
4289 return info->options_len;
4290 err_clear:
4291 memset(to, 0, size);
4292 return err;
4293 }
4294
4295 static const struct bpf_func_proto bpf_skb_get_tunnel_opt_proto = {
4296 .func = bpf_skb_get_tunnel_opt,
4297 .gpl_only = false,
4298 .ret_type = RET_INTEGER,
4299 .arg1_type = ARG_PTR_TO_CTX,
4300 .arg2_type = ARG_PTR_TO_UNINIT_MEM,
4301 .arg3_type = ARG_CONST_SIZE,
4302 };
4303
4304 static struct metadata_dst __percpu *md_dst;
4305
BPF_CALL_4(bpf_skb_set_tunnel_key,struct sk_buff *,skb,const struct bpf_tunnel_key *,from,u32,size,u64,flags)4306 BPF_CALL_4(bpf_skb_set_tunnel_key, struct sk_buff *, skb,
4307 const struct bpf_tunnel_key *, from, u32, size, u64, flags)
4308 {
4309 struct metadata_dst *md = this_cpu_ptr(md_dst);
4310 u8 compat[sizeof(struct bpf_tunnel_key)];
4311 struct ip_tunnel_info *info;
4312
4313 if (unlikely(flags & ~(BPF_F_TUNINFO_IPV6 | BPF_F_ZERO_CSUM_TX |
4314 BPF_F_DONT_FRAGMENT | BPF_F_SEQ_NUMBER)))
4315 return -EINVAL;
4316 if (unlikely(size != sizeof(struct bpf_tunnel_key))) {
4317 switch (size) {
4318 case offsetof(struct bpf_tunnel_key, tunnel_label):
4319 case offsetof(struct bpf_tunnel_key, tunnel_ext):
4320 case offsetof(struct bpf_tunnel_key, remote_ipv6[1]):
4321 /* Fixup deprecated structure layouts here, so we have
4322 * a common path later on.
4323 */
4324 memcpy(compat, from, size);
4325 memset(compat + size, 0, sizeof(compat) - size);
4326 from = (const struct bpf_tunnel_key *) compat;
4327 break;
4328 default:
4329 return -EINVAL;
4330 }
4331 }
4332 if (unlikely((!(flags & BPF_F_TUNINFO_IPV6) && from->tunnel_label) ||
4333 from->tunnel_ext))
4334 return -EINVAL;
4335
4336 skb_dst_drop(skb);
4337 dst_hold((struct dst_entry *) md);
4338 skb_dst_set(skb, (struct dst_entry *) md);
4339
4340 info = &md->u.tun_info;
4341 memset(info, 0, sizeof(*info));
4342 info->mode = IP_TUNNEL_INFO_TX;
4343
4344 info->key.tun_flags = TUNNEL_KEY | TUNNEL_CSUM | TUNNEL_NOCACHE;
4345 if (flags & BPF_F_DONT_FRAGMENT)
4346 info->key.tun_flags |= TUNNEL_DONT_FRAGMENT;
4347 if (flags & BPF_F_ZERO_CSUM_TX)
4348 info->key.tun_flags &= ~TUNNEL_CSUM;
4349 if (flags & BPF_F_SEQ_NUMBER)
4350 info->key.tun_flags |= TUNNEL_SEQ;
4351
4352 info->key.tun_id = cpu_to_be64(from->tunnel_id);
4353 info->key.tos = from->tunnel_tos;
4354 info->key.ttl = from->tunnel_ttl;
4355
4356 if (flags & BPF_F_TUNINFO_IPV6) {
4357 info->mode |= IP_TUNNEL_INFO_IPV6;
4358 memcpy(&info->key.u.ipv6.dst, from->remote_ipv6,
4359 sizeof(from->remote_ipv6));
4360 info->key.label = cpu_to_be32(from->tunnel_label) &
4361 IPV6_FLOWLABEL_MASK;
4362 } else {
4363 info->key.u.ipv4.dst = cpu_to_be32(from->remote_ipv4);
4364 }
4365
4366 return 0;
4367 }
4368
4369 static const struct bpf_func_proto bpf_skb_set_tunnel_key_proto = {
4370 .func = bpf_skb_set_tunnel_key,
4371 .gpl_only = false,
4372 .ret_type = RET_INTEGER,
4373 .arg1_type = ARG_PTR_TO_CTX,
4374 .arg2_type = ARG_PTR_TO_MEM,
4375 .arg3_type = ARG_CONST_SIZE,
4376 .arg4_type = ARG_ANYTHING,
4377 };
4378
BPF_CALL_3(bpf_skb_set_tunnel_opt,struct sk_buff *,skb,const u8 *,from,u32,size)4379 BPF_CALL_3(bpf_skb_set_tunnel_opt, struct sk_buff *, skb,
4380 const u8 *, from, u32, size)
4381 {
4382 struct ip_tunnel_info *info = skb_tunnel_info(skb);
4383 const struct metadata_dst *md = this_cpu_ptr(md_dst);
4384
4385 if (unlikely(info != &md->u.tun_info || (size & (sizeof(u32) - 1))))
4386 return -EINVAL;
4387 if (unlikely(size > IP_TUNNEL_OPTS_MAX))
4388 return -ENOMEM;
4389
4390 ip_tunnel_info_opts_set(info, from, size, TUNNEL_OPTIONS_PRESENT);
4391
4392 return 0;
4393 }
4394
4395 static const struct bpf_func_proto bpf_skb_set_tunnel_opt_proto = {
4396 .func = bpf_skb_set_tunnel_opt,
4397 .gpl_only = false,
4398 .ret_type = RET_INTEGER,
4399 .arg1_type = ARG_PTR_TO_CTX,
4400 .arg2_type = ARG_PTR_TO_MEM,
4401 .arg3_type = ARG_CONST_SIZE,
4402 };
4403
4404 static const struct bpf_func_proto *
bpf_get_skb_set_tunnel_proto(enum bpf_func_id which)4405 bpf_get_skb_set_tunnel_proto(enum bpf_func_id which)
4406 {
4407 if (!md_dst) {
4408 struct metadata_dst __percpu *tmp;
4409
4410 tmp = metadata_dst_alloc_percpu(IP_TUNNEL_OPTS_MAX,
4411 METADATA_IP_TUNNEL,
4412 GFP_KERNEL);
4413 if (!tmp)
4414 return NULL;
4415 if (cmpxchg(&md_dst, NULL, tmp))
4416 metadata_dst_free_percpu(tmp);
4417 }
4418
4419 switch (which) {
4420 case BPF_FUNC_skb_set_tunnel_key:
4421 return &bpf_skb_set_tunnel_key_proto;
4422 case BPF_FUNC_skb_set_tunnel_opt:
4423 return &bpf_skb_set_tunnel_opt_proto;
4424 default:
4425 return NULL;
4426 }
4427 }
4428
BPF_CALL_3(bpf_skb_under_cgroup,struct sk_buff *,skb,struct bpf_map *,map,u32,idx)4429 BPF_CALL_3(bpf_skb_under_cgroup, struct sk_buff *, skb, struct bpf_map *, map,
4430 u32, idx)
4431 {
4432 struct bpf_array *array = container_of(map, struct bpf_array, map);
4433 struct cgroup *cgrp;
4434 struct sock *sk;
4435
4436 sk = skb_to_full_sk(skb);
4437 if (!sk || !sk_fullsock(sk))
4438 return -ENOENT;
4439 if (unlikely(idx >= array->map.max_entries))
4440 return -E2BIG;
4441
4442 cgrp = READ_ONCE(array->ptrs[idx]);
4443 if (unlikely(!cgrp))
4444 return -EAGAIN;
4445
4446 return sk_under_cgroup_hierarchy(sk, cgrp);
4447 }
4448
4449 static const struct bpf_func_proto bpf_skb_under_cgroup_proto = {
4450 .func = bpf_skb_under_cgroup,
4451 .gpl_only = false,
4452 .ret_type = RET_INTEGER,
4453 .arg1_type = ARG_PTR_TO_CTX,
4454 .arg2_type = ARG_CONST_MAP_PTR,
4455 .arg3_type = ARG_ANYTHING,
4456 };
4457
4458 #ifdef CONFIG_SOCK_CGROUP_DATA
__bpf_sk_cgroup_id(struct sock * sk)4459 static inline u64 __bpf_sk_cgroup_id(struct sock *sk)
4460 {
4461 struct cgroup *cgrp;
4462
4463 sk = sk_to_full_sk(sk);
4464 if (!sk || !sk_fullsock(sk))
4465 return 0;
4466
4467 cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
4468 return cgroup_id(cgrp);
4469 }
4470
BPF_CALL_1(bpf_skb_cgroup_id,const struct sk_buff *,skb)4471 BPF_CALL_1(bpf_skb_cgroup_id, const struct sk_buff *, skb)
4472 {
4473 return __bpf_sk_cgroup_id(skb->sk);
4474 }
4475
4476 static const struct bpf_func_proto bpf_skb_cgroup_id_proto = {
4477 .func = bpf_skb_cgroup_id,
4478 .gpl_only = false,
4479 .ret_type = RET_INTEGER,
4480 .arg1_type = ARG_PTR_TO_CTX,
4481 };
4482
__bpf_sk_ancestor_cgroup_id(struct sock * sk,int ancestor_level)4483 static inline u64 __bpf_sk_ancestor_cgroup_id(struct sock *sk,
4484 int ancestor_level)
4485 {
4486 struct cgroup *ancestor;
4487 struct cgroup *cgrp;
4488
4489 sk = sk_to_full_sk(sk);
4490 if (!sk || !sk_fullsock(sk))
4491 return 0;
4492
4493 cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
4494 ancestor = cgroup_ancestor(cgrp, ancestor_level);
4495 if (!ancestor)
4496 return 0;
4497
4498 return cgroup_id(ancestor);
4499 }
4500
BPF_CALL_2(bpf_skb_ancestor_cgroup_id,const struct sk_buff *,skb,int,ancestor_level)4501 BPF_CALL_2(bpf_skb_ancestor_cgroup_id, const struct sk_buff *, skb, int,
4502 ancestor_level)
4503 {
4504 return __bpf_sk_ancestor_cgroup_id(skb->sk, ancestor_level);
4505 }
4506
4507 static const struct bpf_func_proto bpf_skb_ancestor_cgroup_id_proto = {
4508 .func = bpf_skb_ancestor_cgroup_id,
4509 .gpl_only = false,
4510 .ret_type = RET_INTEGER,
4511 .arg1_type = ARG_PTR_TO_CTX,
4512 .arg2_type = ARG_ANYTHING,
4513 };
4514
BPF_CALL_1(bpf_sk_cgroup_id,struct sock *,sk)4515 BPF_CALL_1(bpf_sk_cgroup_id, struct sock *, sk)
4516 {
4517 return __bpf_sk_cgroup_id(sk);
4518 }
4519
4520 static const struct bpf_func_proto bpf_sk_cgroup_id_proto = {
4521 .func = bpf_sk_cgroup_id,
4522 .gpl_only = false,
4523 .ret_type = RET_INTEGER,
4524 .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
4525 };
4526
BPF_CALL_2(bpf_sk_ancestor_cgroup_id,struct sock *,sk,int,ancestor_level)4527 BPF_CALL_2(bpf_sk_ancestor_cgroup_id, struct sock *, sk, int, ancestor_level)
4528 {
4529 return __bpf_sk_ancestor_cgroup_id(sk, ancestor_level);
4530 }
4531
4532 static const struct bpf_func_proto bpf_sk_ancestor_cgroup_id_proto = {
4533 .func = bpf_sk_ancestor_cgroup_id,
4534 .gpl_only = false,
4535 .ret_type = RET_INTEGER,
4536 .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
4537 .arg2_type = ARG_ANYTHING,
4538 };
4539 #endif
4540
bpf_xdp_copy(void * dst_buff,const void * src_buff,unsigned long off,unsigned long len)4541 static unsigned long bpf_xdp_copy(void *dst_buff, const void *src_buff,
4542 unsigned long off, unsigned long len)
4543 {
4544 memcpy(dst_buff, src_buff + off, len);
4545 return 0;
4546 }
4547
BPF_CALL_5(bpf_xdp_event_output,struct xdp_buff *,xdp,struct bpf_map *,map,u64,flags,void *,meta,u64,meta_size)4548 BPF_CALL_5(bpf_xdp_event_output, struct xdp_buff *, xdp, struct bpf_map *, map,
4549 u64, flags, void *, meta, u64, meta_size)
4550 {
4551 u64 xdp_size = (flags & BPF_F_CTXLEN_MASK) >> 32;
4552
4553 if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK)))
4554 return -EINVAL;
4555 if (unlikely(!xdp ||
4556 xdp_size > (unsigned long)(xdp->data_end - xdp->data)))
4557 return -EFAULT;
4558
4559 return bpf_event_output(map, flags, meta, meta_size, xdp->data,
4560 xdp_size, bpf_xdp_copy);
4561 }
4562
4563 static const struct bpf_func_proto bpf_xdp_event_output_proto = {
4564 .func = bpf_xdp_event_output,
4565 .gpl_only = true,
4566 .ret_type = RET_INTEGER,
4567 .arg1_type = ARG_PTR_TO_CTX,
4568 .arg2_type = ARG_CONST_MAP_PTR,
4569 .arg3_type = ARG_ANYTHING,
4570 .arg4_type = ARG_PTR_TO_MEM,
4571 .arg5_type = ARG_CONST_SIZE_OR_ZERO,
4572 };
4573
4574 BTF_ID_LIST_SINGLE(bpf_xdp_output_btf_ids, struct, xdp_buff)
4575
4576 const struct bpf_func_proto bpf_xdp_output_proto = {
4577 .func = bpf_xdp_event_output,
4578 .gpl_only = true,
4579 .ret_type = RET_INTEGER,
4580 .arg1_type = ARG_PTR_TO_BTF_ID,
4581 .arg1_btf_id = &bpf_xdp_output_btf_ids[0],
4582 .arg2_type = ARG_CONST_MAP_PTR,
4583 .arg3_type = ARG_ANYTHING,
4584 .arg4_type = ARG_PTR_TO_MEM,
4585 .arg5_type = ARG_CONST_SIZE_OR_ZERO,
4586 };
4587
BPF_CALL_1(bpf_get_socket_cookie,struct sk_buff *,skb)4588 BPF_CALL_1(bpf_get_socket_cookie, struct sk_buff *, skb)
4589 {
4590 return skb->sk ? __sock_gen_cookie(skb->sk) : 0;
4591 }
4592
4593 static const struct bpf_func_proto bpf_get_socket_cookie_proto = {
4594 .func = bpf_get_socket_cookie,
4595 .gpl_only = false,
4596 .ret_type = RET_INTEGER,
4597 .arg1_type = ARG_PTR_TO_CTX,
4598 };
4599
BPF_CALL_1(bpf_get_socket_cookie_sock_addr,struct bpf_sock_addr_kern *,ctx)4600 BPF_CALL_1(bpf_get_socket_cookie_sock_addr, struct bpf_sock_addr_kern *, ctx)
4601 {
4602 return __sock_gen_cookie(ctx->sk);
4603 }
4604
4605 static const struct bpf_func_proto bpf_get_socket_cookie_sock_addr_proto = {
4606 .func = bpf_get_socket_cookie_sock_addr,
4607 .gpl_only = false,
4608 .ret_type = RET_INTEGER,
4609 .arg1_type = ARG_PTR_TO_CTX,
4610 };
4611
BPF_CALL_1(bpf_get_socket_cookie_sock,struct sock *,ctx)4612 BPF_CALL_1(bpf_get_socket_cookie_sock, struct sock *, ctx)
4613 {
4614 return __sock_gen_cookie(ctx);
4615 }
4616
4617 static const struct bpf_func_proto bpf_get_socket_cookie_sock_proto = {
4618 .func = bpf_get_socket_cookie_sock,
4619 .gpl_only = false,
4620 .ret_type = RET_INTEGER,
4621 .arg1_type = ARG_PTR_TO_CTX,
4622 };
4623
BPF_CALL_1(bpf_get_socket_ptr_cookie,struct sock *,sk)4624 BPF_CALL_1(bpf_get_socket_ptr_cookie, struct sock *, sk)
4625 {
4626 return sk ? sock_gen_cookie(sk) : 0;
4627 }
4628
4629 const struct bpf_func_proto bpf_get_socket_ptr_cookie_proto = {
4630 .func = bpf_get_socket_ptr_cookie,
4631 .gpl_only = false,
4632 .ret_type = RET_INTEGER,
4633 .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
4634 };
4635
BPF_CALL_1(bpf_get_socket_cookie_sock_ops,struct bpf_sock_ops_kern *,ctx)4636 BPF_CALL_1(bpf_get_socket_cookie_sock_ops, struct bpf_sock_ops_kern *, ctx)
4637 {
4638 return __sock_gen_cookie(ctx->sk);
4639 }
4640
4641 static const struct bpf_func_proto bpf_get_socket_cookie_sock_ops_proto = {
4642 .func = bpf_get_socket_cookie_sock_ops,
4643 .gpl_only = false,
4644 .ret_type = RET_INTEGER,
4645 .arg1_type = ARG_PTR_TO_CTX,
4646 };
4647
__bpf_get_netns_cookie(struct sock * sk)4648 static u64 __bpf_get_netns_cookie(struct sock *sk)
4649 {
4650 const struct net *net = sk ? sock_net(sk) : &init_net;
4651
4652 return net->net_cookie;
4653 }
4654
BPF_CALL_1(bpf_get_netns_cookie_sock,struct sock *,ctx)4655 BPF_CALL_1(bpf_get_netns_cookie_sock, struct sock *, ctx)
4656 {
4657 return __bpf_get_netns_cookie(ctx);
4658 }
4659
4660 static const struct bpf_func_proto bpf_get_netns_cookie_sock_proto = {
4661 .func = bpf_get_netns_cookie_sock,
4662 .gpl_only = false,
4663 .ret_type = RET_INTEGER,
4664 .arg1_type = ARG_PTR_TO_CTX_OR_NULL,
4665 };
4666
BPF_CALL_1(bpf_get_netns_cookie_sock_addr,struct bpf_sock_addr_kern *,ctx)4667 BPF_CALL_1(bpf_get_netns_cookie_sock_addr, struct bpf_sock_addr_kern *, ctx)
4668 {
4669 return __bpf_get_netns_cookie(ctx ? ctx->sk : NULL);
4670 }
4671
4672 static const struct bpf_func_proto bpf_get_netns_cookie_sock_addr_proto = {
4673 .func = bpf_get_netns_cookie_sock_addr,
4674 .gpl_only = false,
4675 .ret_type = RET_INTEGER,
4676 .arg1_type = ARG_PTR_TO_CTX_OR_NULL,
4677 };
4678
BPF_CALL_1(bpf_get_netns_cookie_sock_ops,struct bpf_sock_ops_kern *,ctx)4679 BPF_CALL_1(bpf_get_netns_cookie_sock_ops, struct bpf_sock_ops_kern *, ctx)
4680 {
4681 return __bpf_get_netns_cookie(ctx ? ctx->sk : NULL);
4682 }
4683
4684 static const struct bpf_func_proto bpf_get_netns_cookie_sock_ops_proto = {
4685 .func = bpf_get_netns_cookie_sock_ops,
4686 .gpl_only = false,
4687 .ret_type = RET_INTEGER,
4688 .arg1_type = ARG_PTR_TO_CTX_OR_NULL,
4689 };
4690
BPF_CALL_1(bpf_get_netns_cookie_sk_msg,struct sk_msg *,ctx)4691 BPF_CALL_1(bpf_get_netns_cookie_sk_msg, struct sk_msg *, ctx)
4692 {
4693 return __bpf_get_netns_cookie(ctx ? ctx->sk : NULL);
4694 }
4695
4696 static const struct bpf_func_proto bpf_get_netns_cookie_sk_msg_proto = {
4697 .func = bpf_get_netns_cookie_sk_msg,
4698 .gpl_only = false,
4699 .ret_type = RET_INTEGER,
4700 .arg1_type = ARG_PTR_TO_CTX_OR_NULL,
4701 };
4702
BPF_CALL_1(bpf_get_socket_uid,struct sk_buff *,skb)4703 BPF_CALL_1(bpf_get_socket_uid, struct sk_buff *, skb)
4704 {
4705 struct sock *sk = sk_to_full_sk(skb->sk);
4706 kuid_t kuid;
4707
4708 if (!sk || !sk_fullsock(sk))
4709 return overflowuid;
4710 kuid = sock_net_uid(sock_net(sk), sk);
4711 return from_kuid_munged(sock_net(sk)->user_ns, kuid);
4712 }
4713
4714 static const struct bpf_func_proto bpf_get_socket_uid_proto = {
4715 .func = bpf_get_socket_uid,
4716 .gpl_only = false,
4717 .ret_type = RET_INTEGER,
4718 .arg1_type = ARG_PTR_TO_CTX,
4719 };
4720
_bpf_setsockopt(struct sock * sk,int level,int optname,char * optval,int optlen)4721 static int _bpf_setsockopt(struct sock *sk, int level, int optname,
4722 char *optval, int optlen)
4723 {
4724 char devname[IFNAMSIZ];
4725 int val, valbool;
4726 struct net *net;
4727 int ifindex;
4728 int ret = 0;
4729
4730 if (!sk_fullsock(sk))
4731 return -EINVAL;
4732
4733 sock_owned_by_me(sk);
4734
4735 if (level == SOL_SOCKET) {
4736 if (optlen != sizeof(int) && optname != SO_BINDTODEVICE)
4737 return -EINVAL;
4738 val = *((int *)optval);
4739 valbool = val ? 1 : 0;
4740
4741 /* Only some socketops are supported */
4742 switch (optname) {
4743 case SO_RCVBUF:
4744 val = min_t(u32, val, sysctl_rmem_max);
4745 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
4746 WRITE_ONCE(sk->sk_rcvbuf,
4747 max_t(int, val * 2, SOCK_MIN_RCVBUF));
4748 break;
4749 case SO_SNDBUF:
4750 val = min_t(u32, val, sysctl_wmem_max);
4751 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
4752 WRITE_ONCE(sk->sk_sndbuf,
4753 max_t(int, val * 2, SOCK_MIN_SNDBUF));
4754 break;
4755 case SO_MAX_PACING_RATE: /* 32bit version */
4756 if (val != ~0U)
4757 cmpxchg(&sk->sk_pacing_status,
4758 SK_PACING_NONE,
4759 SK_PACING_NEEDED);
4760 sk->sk_max_pacing_rate = (val == ~0U) ?
4761 ~0UL : (unsigned int)val;
4762 sk->sk_pacing_rate = min(sk->sk_pacing_rate,
4763 sk->sk_max_pacing_rate);
4764 break;
4765 case SO_PRIORITY:
4766 sk->sk_priority = val;
4767 break;
4768 case SO_RCVLOWAT:
4769 if (val < 0)
4770 val = INT_MAX;
4771 WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
4772 break;
4773 case SO_MARK:
4774 if (sk->sk_mark != val) {
4775 sk->sk_mark = val;
4776 sk_dst_reset(sk);
4777 }
4778 break;
4779 case SO_BINDTODEVICE:
4780 optlen = min_t(long, optlen, IFNAMSIZ - 1);
4781 strncpy(devname, optval, optlen);
4782 devname[optlen] = 0;
4783
4784 ifindex = 0;
4785 if (devname[0] != '\0') {
4786 struct net_device *dev;
4787
4788 ret = -ENODEV;
4789
4790 net = sock_net(sk);
4791 dev = dev_get_by_name(net, devname);
4792 if (!dev)
4793 break;
4794 ifindex = dev->ifindex;
4795 dev_put(dev);
4796 }
4797 fallthrough;
4798 case SO_BINDTOIFINDEX:
4799 if (optname == SO_BINDTOIFINDEX)
4800 ifindex = val;
4801 ret = sock_bindtoindex(sk, ifindex, false);
4802 break;
4803 case SO_KEEPALIVE:
4804 if (sk->sk_prot->keepalive)
4805 sk->sk_prot->keepalive(sk, valbool);
4806 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
4807 break;
4808 case SO_REUSEPORT:
4809 sk->sk_reuseport = valbool;
4810 break;
4811 default:
4812 ret = -EINVAL;
4813 }
4814 #ifdef CONFIG_INET
4815 } else if (level == SOL_IP) {
4816 if (optlen != sizeof(int) || sk->sk_family != AF_INET)
4817 return -EINVAL;
4818
4819 val = *((int *)optval);
4820 /* Only some options are supported */
4821 switch (optname) {
4822 case IP_TOS:
4823 if (val < -1 || val > 0xff) {
4824 ret = -EINVAL;
4825 } else {
4826 struct inet_sock *inet = inet_sk(sk);
4827
4828 if (val == -1)
4829 val = 0;
4830 inet->tos = val;
4831 }
4832 break;
4833 default:
4834 ret = -EINVAL;
4835 }
4836 #if IS_ENABLED(CONFIG_IPV6)
4837 } else if (level == SOL_IPV6) {
4838 if (optlen != sizeof(int) || sk->sk_family != AF_INET6)
4839 return -EINVAL;
4840
4841 val = *((int *)optval);
4842 /* Only some options are supported */
4843 switch (optname) {
4844 case IPV6_TCLASS:
4845 if (val < -1 || val > 0xff) {
4846 ret = -EINVAL;
4847 } else {
4848 struct ipv6_pinfo *np = inet6_sk(sk);
4849
4850 if (val == -1)
4851 val = 0;
4852 np->tclass = val;
4853 }
4854 break;
4855 default:
4856 ret = -EINVAL;
4857 }
4858 #endif
4859 } else if (level == SOL_TCP &&
4860 sk->sk_prot->setsockopt == tcp_setsockopt) {
4861 if (optname == TCP_CONGESTION) {
4862 char name[TCP_CA_NAME_MAX];
4863
4864 strncpy(name, optval, min_t(long, optlen,
4865 TCP_CA_NAME_MAX-1));
4866 name[TCP_CA_NAME_MAX-1] = 0;
4867 ret = tcp_set_congestion_control(sk, name, false, true);
4868 } else {
4869 struct inet_connection_sock *icsk = inet_csk(sk);
4870 struct tcp_sock *tp = tcp_sk(sk);
4871 unsigned long timeout;
4872
4873 if (optlen != sizeof(int))
4874 return -EINVAL;
4875
4876 val = *((int *)optval);
4877 /* Only some options are supported */
4878 switch (optname) {
4879 case TCP_BPF_IW:
4880 if (val <= 0 || tp->data_segs_out > tp->syn_data)
4881 ret = -EINVAL;
4882 else
4883 tp->snd_cwnd = val;
4884 break;
4885 case TCP_BPF_SNDCWND_CLAMP:
4886 if (val <= 0) {
4887 ret = -EINVAL;
4888 } else {
4889 tp->snd_cwnd_clamp = val;
4890 tp->snd_ssthresh = val;
4891 }
4892 break;
4893 case TCP_BPF_DELACK_MAX:
4894 timeout = usecs_to_jiffies(val);
4895 if (timeout > TCP_DELACK_MAX ||
4896 timeout < TCP_TIMEOUT_MIN)
4897 return -EINVAL;
4898 inet_csk(sk)->icsk_delack_max = timeout;
4899 break;
4900 case TCP_BPF_RTO_MIN:
4901 timeout = usecs_to_jiffies(val);
4902 if (timeout > TCP_RTO_MIN ||
4903 timeout < TCP_TIMEOUT_MIN)
4904 return -EINVAL;
4905 inet_csk(sk)->icsk_rto_min = timeout;
4906 break;
4907 case TCP_SAVE_SYN:
4908 if (val < 0 || val > 1)
4909 ret = -EINVAL;
4910 else
4911 tp->save_syn = val;
4912 break;
4913 case TCP_KEEPIDLE:
4914 ret = tcp_sock_set_keepidle_locked(sk, val);
4915 break;
4916 case TCP_KEEPINTVL:
4917 if (val < 1 || val > MAX_TCP_KEEPINTVL)
4918 ret = -EINVAL;
4919 else
4920 tp->keepalive_intvl = val * HZ;
4921 break;
4922 case TCP_KEEPCNT:
4923 if (val < 1 || val > MAX_TCP_KEEPCNT)
4924 ret = -EINVAL;
4925 else
4926 tp->keepalive_probes = val;
4927 break;
4928 case TCP_SYNCNT:
4929 if (val < 1 || val > MAX_TCP_SYNCNT)
4930 ret = -EINVAL;
4931 else
4932 icsk->icsk_syn_retries = val;
4933 break;
4934 case TCP_USER_TIMEOUT:
4935 if (val < 0)
4936 ret = -EINVAL;
4937 else
4938 icsk->icsk_user_timeout = val;
4939 break;
4940 case TCP_NOTSENT_LOWAT:
4941 tp->notsent_lowat = val;
4942 sk->sk_write_space(sk);
4943 break;
4944 case TCP_WINDOW_CLAMP:
4945 ret = tcp_set_window_clamp(sk, val);
4946 break;
4947 default:
4948 ret = -EINVAL;
4949 }
4950 }
4951 #endif
4952 } else {
4953 ret = -EINVAL;
4954 }
4955 return ret;
4956 }
4957
_bpf_getsockopt(struct sock * sk,int level,int optname,char * optval,int optlen)4958 static int _bpf_getsockopt(struct sock *sk, int level, int optname,
4959 char *optval, int optlen)
4960 {
4961 if (!sk_fullsock(sk))
4962 goto err_clear;
4963
4964 sock_owned_by_me(sk);
4965
4966 if (level == SOL_SOCKET) {
4967 if (optlen != sizeof(int))
4968 goto err_clear;
4969
4970 switch (optname) {
4971 case SO_MARK:
4972 *((int *)optval) = sk->sk_mark;
4973 break;
4974 case SO_PRIORITY:
4975 *((int *)optval) = sk->sk_priority;
4976 break;
4977 case SO_BINDTOIFINDEX:
4978 *((int *)optval) = sk->sk_bound_dev_if;
4979 break;
4980 case SO_REUSEPORT:
4981 *((int *)optval) = sk->sk_reuseport;
4982 break;
4983 default:
4984 goto err_clear;
4985 }
4986 #ifdef CONFIG_INET
4987 } else if (level == SOL_TCP && sk->sk_prot->getsockopt == tcp_getsockopt) {
4988 struct inet_connection_sock *icsk;
4989 struct tcp_sock *tp;
4990
4991 switch (optname) {
4992 case TCP_CONGESTION:
4993 icsk = inet_csk(sk);
4994
4995 if (!icsk->icsk_ca_ops || optlen <= 1)
4996 goto err_clear;
4997 strncpy(optval, icsk->icsk_ca_ops->name, optlen);
4998 optval[optlen - 1] = 0;
4999 break;
5000 case TCP_SAVED_SYN:
5001 tp = tcp_sk(sk);
5002
5003 if (optlen <= 0 || !tp->saved_syn ||
5004 optlen > tcp_saved_syn_len(tp->saved_syn))
5005 goto err_clear;
5006 memcpy(optval, tp->saved_syn->data, optlen);
5007 break;
5008 default:
5009 goto err_clear;
5010 }
5011 } else if (level == SOL_IP) {
5012 struct inet_sock *inet = inet_sk(sk);
5013
5014 if (optlen != sizeof(int) || sk->sk_family != AF_INET)
5015 goto err_clear;
5016
5017 /* Only some options are supported */
5018 switch (optname) {
5019 case IP_TOS:
5020 *((int *)optval) = (int)inet->tos;
5021 break;
5022 default:
5023 goto err_clear;
5024 }
5025 #if IS_ENABLED(CONFIG_IPV6)
5026 } else if (level == SOL_IPV6) {
5027 struct ipv6_pinfo *np = inet6_sk(sk);
5028
5029 if (optlen != sizeof(int) || sk->sk_family != AF_INET6)
5030 goto err_clear;
5031
5032 /* Only some options are supported */
5033 switch (optname) {
5034 case IPV6_TCLASS:
5035 *((int *)optval) = (int)np->tclass;
5036 break;
5037 default:
5038 goto err_clear;
5039 }
5040 #endif
5041 #endif
5042 } else {
5043 goto err_clear;
5044 }
5045 return 0;
5046 err_clear:
5047 memset(optval, 0, optlen);
5048 return -EINVAL;
5049 }
5050
BPF_CALL_5(bpf_sk_setsockopt,struct sock *,sk,int,level,int,optname,char *,optval,int,optlen)5051 BPF_CALL_5(bpf_sk_setsockopt, struct sock *, sk, int, level,
5052 int, optname, char *, optval, int, optlen)
5053 {
5054 if (level == SOL_TCP && optname == TCP_CONGESTION) {
5055 if (optlen >= sizeof("cdg") - 1 &&
5056 !strncmp("cdg", optval, optlen))
5057 return -ENOTSUPP;
5058 }
5059
5060 return _bpf_setsockopt(sk, level, optname, optval, optlen);
5061 }
5062
5063 const struct bpf_func_proto bpf_sk_setsockopt_proto = {
5064 .func = bpf_sk_setsockopt,
5065 .gpl_only = false,
5066 .ret_type = RET_INTEGER,
5067 .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
5068 .arg2_type = ARG_ANYTHING,
5069 .arg3_type = ARG_ANYTHING,
5070 .arg4_type = ARG_PTR_TO_MEM,
5071 .arg5_type = ARG_CONST_SIZE,
5072 };
5073
BPF_CALL_5(bpf_sk_getsockopt,struct sock *,sk,int,level,int,optname,char *,optval,int,optlen)5074 BPF_CALL_5(bpf_sk_getsockopt, struct sock *, sk, int, level,
5075 int, optname, char *, optval, int, optlen)
5076 {
5077 return _bpf_getsockopt(sk, level, optname, optval, optlen);
5078 }
5079
5080 const struct bpf_func_proto bpf_sk_getsockopt_proto = {
5081 .func = bpf_sk_getsockopt,
5082 .gpl_only = false,
5083 .ret_type = RET_INTEGER,
5084 .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
5085 .arg2_type = ARG_ANYTHING,
5086 .arg3_type = ARG_ANYTHING,
5087 .arg4_type = ARG_PTR_TO_UNINIT_MEM,
5088 .arg5_type = ARG_CONST_SIZE,
5089 };
5090
BPF_CALL_5(bpf_sock_addr_setsockopt,struct bpf_sock_addr_kern *,ctx,int,level,int,optname,char *,optval,int,optlen)5091 BPF_CALL_5(bpf_sock_addr_setsockopt, struct bpf_sock_addr_kern *, ctx,
5092 int, level, int, optname, char *, optval, int, optlen)
5093 {
5094 return _bpf_setsockopt(ctx->sk, level, optname, optval, optlen);
5095 }
5096
5097 static const struct bpf_func_proto bpf_sock_addr_setsockopt_proto = {
5098 .func = bpf_sock_addr_setsockopt,
5099 .gpl_only = false,
5100 .ret_type = RET_INTEGER,
5101 .arg1_type = ARG_PTR_TO_CTX,
5102 .arg2_type = ARG_ANYTHING,
5103 .arg3_type = ARG_ANYTHING,
5104 .arg4_type = ARG_PTR_TO_MEM,
5105 .arg5_type = ARG_CONST_SIZE,
5106 };
5107
BPF_CALL_5(bpf_sock_addr_getsockopt,struct bpf_sock_addr_kern *,ctx,int,level,int,optname,char *,optval,int,optlen)5108 BPF_CALL_5(bpf_sock_addr_getsockopt, struct bpf_sock_addr_kern *, ctx,
5109 int, level, int, optname, char *, optval, int, optlen)
5110 {
5111 return _bpf_getsockopt(ctx->sk, level, optname, optval, optlen);
5112 }
5113
5114 static const struct bpf_func_proto bpf_sock_addr_getsockopt_proto = {
5115 .func = bpf_sock_addr_getsockopt,
5116 .gpl_only = false,
5117 .ret_type = RET_INTEGER,
5118 .arg1_type = ARG_PTR_TO_CTX,
5119 .arg2_type = ARG_ANYTHING,
5120 .arg3_type = ARG_ANYTHING,
5121 .arg4_type = ARG_PTR_TO_UNINIT_MEM,
5122 .arg5_type = ARG_CONST_SIZE,
5123 };
5124
BPF_CALL_5(bpf_sock_ops_setsockopt,struct bpf_sock_ops_kern *,bpf_sock,int,level,int,optname,char *,optval,int,optlen)5125 BPF_CALL_5(bpf_sock_ops_setsockopt, struct bpf_sock_ops_kern *, bpf_sock,
5126 int, level, int, optname, char *, optval, int, optlen)
5127 {
5128 return _bpf_setsockopt(bpf_sock->sk, level, optname, optval, optlen);
5129 }
5130
5131 static const struct bpf_func_proto bpf_sock_ops_setsockopt_proto = {
5132 .func = bpf_sock_ops_setsockopt,
5133 .gpl_only = false,
5134 .ret_type = RET_INTEGER,
5135 .arg1_type = ARG_PTR_TO_CTX,
5136 .arg2_type = ARG_ANYTHING,
5137 .arg3_type = ARG_ANYTHING,
5138 .arg4_type = ARG_PTR_TO_MEM,
5139 .arg5_type = ARG_CONST_SIZE,
5140 };
5141
bpf_sock_ops_get_syn(struct bpf_sock_ops_kern * bpf_sock,int optname,const u8 ** start)5142 static int bpf_sock_ops_get_syn(struct bpf_sock_ops_kern *bpf_sock,
5143 int optname, const u8 **start)
5144 {
5145 struct sk_buff *syn_skb = bpf_sock->syn_skb;
5146 const u8 *hdr_start;
5147 int ret;
5148
5149 if (syn_skb) {
5150 /* sk is a request_sock here */
5151
5152 if (optname == TCP_BPF_SYN) {
5153 hdr_start = syn_skb->data;
5154 ret = tcp_hdrlen(syn_skb);
5155 } else if (optname == TCP_BPF_SYN_IP) {
5156 hdr_start = skb_network_header(syn_skb);
5157 ret = skb_network_header_len(syn_skb) +
5158 tcp_hdrlen(syn_skb);
5159 } else {
5160 /* optname == TCP_BPF_SYN_MAC */
5161 hdr_start = skb_mac_header(syn_skb);
5162 ret = skb_mac_header_len(syn_skb) +
5163 skb_network_header_len(syn_skb) +
5164 tcp_hdrlen(syn_skb);
5165 }
5166 } else {
5167 struct sock *sk = bpf_sock->sk;
5168 struct saved_syn *saved_syn;
5169
5170 if (sk->sk_state == TCP_NEW_SYN_RECV)
5171 /* synack retransmit. bpf_sock->syn_skb will
5172 * not be available. It has to resort to
5173 * saved_syn (if it is saved).
5174 */
5175 saved_syn = inet_reqsk(sk)->saved_syn;
5176 else
5177 saved_syn = tcp_sk(sk)->saved_syn;
5178
5179 if (!saved_syn)
5180 return -ENOENT;
5181
5182 if (optname == TCP_BPF_SYN) {
5183 hdr_start = saved_syn->data +
5184 saved_syn->mac_hdrlen +
5185 saved_syn->network_hdrlen;
5186 ret = saved_syn->tcp_hdrlen;
5187 } else if (optname == TCP_BPF_SYN_IP) {
5188 hdr_start = saved_syn->data +
5189 saved_syn->mac_hdrlen;
5190 ret = saved_syn->network_hdrlen +
5191 saved_syn->tcp_hdrlen;
5192 } else {
5193 /* optname == TCP_BPF_SYN_MAC */
5194
5195 /* TCP_SAVE_SYN may not have saved the mac hdr */
5196 if (!saved_syn->mac_hdrlen)
5197 return -ENOENT;
5198
5199 hdr_start = saved_syn->data;
5200 ret = saved_syn->mac_hdrlen +
5201 saved_syn->network_hdrlen +
5202 saved_syn->tcp_hdrlen;
5203 }
5204 }
5205
5206 *start = hdr_start;
5207 return ret;
5208 }
5209
BPF_CALL_5(bpf_sock_ops_getsockopt,struct bpf_sock_ops_kern *,bpf_sock,int,level,int,optname,char *,optval,int,optlen)5210 BPF_CALL_5(bpf_sock_ops_getsockopt, struct bpf_sock_ops_kern *, bpf_sock,
5211 int, level, int, optname, char *, optval, int, optlen)
5212 {
5213 if (IS_ENABLED(CONFIG_INET) && level == SOL_TCP &&
5214 optname >= TCP_BPF_SYN && optname <= TCP_BPF_SYN_MAC) {
5215 int ret, copy_len = 0;
5216 const u8 *start;
5217
5218 ret = bpf_sock_ops_get_syn(bpf_sock, optname, &start);
5219 if (ret > 0) {
5220 copy_len = ret;
5221 if (optlen < copy_len) {
5222 copy_len = optlen;
5223 ret = -ENOSPC;
5224 }
5225
5226 memcpy(optval, start, copy_len);
5227 }
5228
5229 /* Zero out unused buffer at the end */
5230 memset(optval + copy_len, 0, optlen - copy_len);
5231
5232 return ret;
5233 }
5234
5235 return _bpf_getsockopt(bpf_sock->sk, level, optname, optval, optlen);
5236 }
5237
5238 static const struct bpf_func_proto bpf_sock_ops_getsockopt_proto = {
5239 .func = bpf_sock_ops_getsockopt,
5240 .gpl_only = false,
5241 .ret_type = RET_INTEGER,
5242 .arg1_type = ARG_PTR_TO_CTX,
5243 .arg2_type = ARG_ANYTHING,
5244 .arg3_type = ARG_ANYTHING,
5245 .arg4_type = ARG_PTR_TO_UNINIT_MEM,
5246 .arg5_type = ARG_CONST_SIZE,
5247 };
5248
BPF_CALL_2(bpf_sock_ops_cb_flags_set,struct bpf_sock_ops_kern *,bpf_sock,int,argval)5249 BPF_CALL_2(bpf_sock_ops_cb_flags_set, struct bpf_sock_ops_kern *, bpf_sock,
5250 int, argval)
5251 {
5252 struct sock *sk = bpf_sock->sk;
5253 int val = argval & BPF_SOCK_OPS_ALL_CB_FLAGS;
5254
5255 if (!IS_ENABLED(CONFIG_INET) || !sk_fullsock(sk))
5256 return -EINVAL;
5257
5258 tcp_sk(sk)->bpf_sock_ops_cb_flags = val;
5259
5260 return argval & (~BPF_SOCK_OPS_ALL_CB_FLAGS);
5261 }
5262
5263 static const struct bpf_func_proto bpf_sock_ops_cb_flags_set_proto = {
5264 .func = bpf_sock_ops_cb_flags_set,
5265 .gpl_only = false,
5266 .ret_type = RET_INTEGER,
5267 .arg1_type = ARG_PTR_TO_CTX,
5268 .arg2_type = ARG_ANYTHING,
5269 };
5270
5271 const struct ipv6_bpf_stub *ipv6_bpf_stub __read_mostly;
5272 EXPORT_SYMBOL_GPL(ipv6_bpf_stub);
5273
BPF_CALL_3(bpf_bind,struct bpf_sock_addr_kern *,ctx,struct sockaddr *,addr,int,addr_len)5274 BPF_CALL_3(bpf_bind, struct bpf_sock_addr_kern *, ctx, struct sockaddr *, addr,
5275 int, addr_len)
5276 {
5277 #ifdef CONFIG_INET
5278 struct sock *sk = ctx->sk;
5279 u32 flags = BIND_FROM_BPF;
5280 int err;
5281
5282 err = -EINVAL;
5283 if (addr_len < offsetofend(struct sockaddr, sa_family))
5284 return err;
5285 if (addr->sa_family == AF_INET) {
5286 if (addr_len < sizeof(struct sockaddr_in))
5287 return err;
5288 if (((struct sockaddr_in *)addr)->sin_port == htons(0))
5289 flags |= BIND_FORCE_ADDRESS_NO_PORT;
5290 return __inet_bind(sk, addr, addr_len, flags);
5291 #if IS_ENABLED(CONFIG_IPV6)
5292 } else if (addr->sa_family == AF_INET6) {
5293 if (addr_len < SIN6_LEN_RFC2133)
5294 return err;
5295 if (((struct sockaddr_in6 *)addr)->sin6_port == htons(0))
5296 flags |= BIND_FORCE_ADDRESS_NO_PORT;
5297 /* ipv6_bpf_stub cannot be NULL, since it's called from
5298 * bpf_cgroup_inet6_connect hook and ipv6 is already loaded
5299 */
5300 return ipv6_bpf_stub->inet6_bind(sk, addr, addr_len, flags);
5301 #endif /* CONFIG_IPV6 */
5302 }
5303 #endif /* CONFIG_INET */
5304
5305 return -EAFNOSUPPORT;
5306 }
5307
5308 static const struct bpf_func_proto bpf_bind_proto = {
5309 .func = bpf_bind,
5310 .gpl_only = false,
5311 .ret_type = RET_INTEGER,
5312 .arg1_type = ARG_PTR_TO_CTX,
5313 .arg2_type = ARG_PTR_TO_MEM,
5314 .arg3_type = ARG_CONST_SIZE,
5315 };
5316
5317 #ifdef CONFIG_XFRM
BPF_CALL_5(bpf_skb_get_xfrm_state,struct sk_buff *,skb,u32,index,struct bpf_xfrm_state *,to,u32,size,u64,flags)5318 BPF_CALL_5(bpf_skb_get_xfrm_state, struct sk_buff *, skb, u32, index,
5319 struct bpf_xfrm_state *, to, u32, size, u64, flags)
5320 {
5321 const struct sec_path *sp = skb_sec_path(skb);
5322 const struct xfrm_state *x;
5323
5324 if (!sp || unlikely(index >= sp->len || flags))
5325 goto err_clear;
5326
5327 x = sp->xvec[index];
5328
5329 if (unlikely(size != sizeof(struct bpf_xfrm_state)))
5330 goto err_clear;
5331
5332 to->reqid = x->props.reqid;
5333 to->spi = x->id.spi;
5334 to->family = x->props.family;
5335 to->ext = 0;
5336
5337 if (to->family == AF_INET6) {
5338 memcpy(to->remote_ipv6, x->props.saddr.a6,
5339 sizeof(to->remote_ipv6));
5340 } else {
5341 to->remote_ipv4 = x->props.saddr.a4;
5342 memset(&to->remote_ipv6[1], 0, sizeof(__u32) * 3);
5343 }
5344
5345 return 0;
5346 err_clear:
5347 memset(to, 0, size);
5348 return -EINVAL;
5349 }
5350
5351 static const struct bpf_func_proto bpf_skb_get_xfrm_state_proto = {
5352 .func = bpf_skb_get_xfrm_state,
5353 .gpl_only = false,
5354 .ret_type = RET_INTEGER,
5355 .arg1_type = ARG_PTR_TO_CTX,
5356 .arg2_type = ARG_ANYTHING,
5357 .arg3_type = ARG_PTR_TO_UNINIT_MEM,
5358 .arg4_type = ARG_CONST_SIZE,
5359 .arg5_type = ARG_ANYTHING,
5360 };
5361 #endif
5362
5363 #if IS_ENABLED(CONFIG_INET) || IS_ENABLED(CONFIG_IPV6)
bpf_fib_set_fwd_params(struct bpf_fib_lookup * params,const struct neighbour * neigh,const struct net_device * dev,u32 mtu)5364 static int bpf_fib_set_fwd_params(struct bpf_fib_lookup *params,
5365 const struct neighbour *neigh,
5366 const struct net_device *dev, u32 mtu)
5367 {
5368 memcpy(params->dmac, neigh->ha, ETH_ALEN);
5369 memcpy(params->smac, dev->dev_addr, ETH_ALEN);
5370 params->h_vlan_TCI = 0;
5371 params->h_vlan_proto = 0;
5372 if (mtu)
5373 params->mtu_result = mtu; /* union with tot_len */
5374
5375 return 0;
5376 }
5377 #endif
5378
5379 #if IS_ENABLED(CONFIG_INET)
bpf_ipv4_fib_lookup(struct net * net,struct bpf_fib_lookup * params,u32 flags,bool check_mtu)5380 static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
5381 u32 flags, bool check_mtu)
5382 {
5383 struct fib_nh_common *nhc;
5384 struct in_device *in_dev;
5385 struct neighbour *neigh;
5386 struct net_device *dev;
5387 struct fib_result res;
5388 struct flowi4 fl4;
5389 u32 mtu = 0;
5390 int err;
5391
5392 dev = dev_get_by_index_rcu(net, params->ifindex);
5393 if (unlikely(!dev))
5394 return -ENODEV;
5395
5396 /* verify forwarding is enabled on this interface */
5397 in_dev = __in_dev_get_rcu(dev);
5398 if (unlikely(!in_dev || !IN_DEV_FORWARD(in_dev)))
5399 return BPF_FIB_LKUP_RET_FWD_DISABLED;
5400
5401 if (flags & BPF_FIB_LOOKUP_OUTPUT) {
5402 fl4.flowi4_iif = 1;
5403 fl4.flowi4_oif = params->ifindex;
5404 } else {
5405 fl4.flowi4_iif = params->ifindex;
5406 fl4.flowi4_oif = 0;
5407 }
5408 fl4.flowi4_tos = params->tos & IPTOS_RT_MASK;
5409 fl4.flowi4_scope = RT_SCOPE_UNIVERSE;
5410 fl4.flowi4_flags = 0;
5411
5412 fl4.flowi4_proto = params->l4_protocol;
5413 fl4.daddr = params->ipv4_dst;
5414 fl4.saddr = params->ipv4_src;
5415 fl4.fl4_sport = params->sport;
5416 fl4.fl4_dport = params->dport;
5417 fl4.flowi4_multipath_hash = 0;
5418
5419 if (flags & BPF_FIB_LOOKUP_DIRECT) {
5420 u32 tbid = l3mdev_fib_table_rcu(dev) ? : RT_TABLE_MAIN;
5421 struct fib_table *tb;
5422
5423 tb = fib_get_table(net, tbid);
5424 if (unlikely(!tb))
5425 return BPF_FIB_LKUP_RET_NOT_FWDED;
5426
5427 err = fib_table_lookup(tb, &fl4, &res, FIB_LOOKUP_NOREF);
5428 } else {
5429 fl4.flowi4_mark = 0;
5430 fl4.flowi4_secid = 0;
5431 fl4.flowi4_tun_key.tun_id = 0;
5432 fl4.flowi4_uid = sock_net_uid(net, NULL);
5433
5434 err = fib_lookup(net, &fl4, &res, FIB_LOOKUP_NOREF);
5435 }
5436
5437 if (err) {
5438 /* map fib lookup errors to RTN_ type */
5439 if (err == -EINVAL)
5440 return BPF_FIB_LKUP_RET_BLACKHOLE;
5441 if (err == -EHOSTUNREACH)
5442 return BPF_FIB_LKUP_RET_UNREACHABLE;
5443 if (err == -EACCES)
5444 return BPF_FIB_LKUP_RET_PROHIBIT;
5445
5446 return BPF_FIB_LKUP_RET_NOT_FWDED;
5447 }
5448
5449 if (res.type != RTN_UNICAST)
5450 return BPF_FIB_LKUP_RET_NOT_FWDED;
5451
5452 if (fib_info_num_path(res.fi) > 1)
5453 fib_select_path(net, &res, &fl4, NULL);
5454
5455 if (check_mtu) {
5456 mtu = ip_mtu_from_fib_result(&res, params->ipv4_dst);
5457 if (params->tot_len > mtu) {
5458 params->mtu_result = mtu; /* union with tot_len */
5459 return BPF_FIB_LKUP_RET_FRAG_NEEDED;
5460 }
5461 }
5462
5463 nhc = res.nhc;
5464
5465 /* do not handle lwt encaps right now */
5466 if (nhc->nhc_lwtstate)
5467 return BPF_FIB_LKUP_RET_UNSUPP_LWT;
5468
5469 dev = nhc->nhc_dev;
5470
5471 params->rt_metric = res.fi->fib_priority;
5472 params->ifindex = dev->ifindex;
5473
5474 /* xdp and cls_bpf programs are run in RCU-bh so
5475 * rcu_read_lock_bh is not needed here
5476 */
5477 if (likely(nhc->nhc_gw_family != AF_INET6)) {
5478 if (nhc->nhc_gw_family)
5479 params->ipv4_dst = nhc->nhc_gw.ipv4;
5480
5481 neigh = __ipv4_neigh_lookup_noref(dev,
5482 (__force u32)params->ipv4_dst);
5483 } else {
5484 struct in6_addr *dst = (struct in6_addr *)params->ipv6_dst;
5485
5486 params->family = AF_INET6;
5487 *dst = nhc->nhc_gw.ipv6;
5488 neigh = __ipv6_neigh_lookup_noref_stub(dev, dst);
5489 }
5490
5491 if (!neigh)
5492 return BPF_FIB_LKUP_RET_NO_NEIGH;
5493
5494 return bpf_fib_set_fwd_params(params, neigh, dev, mtu);
5495 }
5496 #endif
5497
5498 #if IS_ENABLED(CONFIG_IPV6)
bpf_ipv6_fib_lookup(struct net * net,struct bpf_fib_lookup * params,u32 flags,bool check_mtu)5499 static int bpf_ipv6_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
5500 u32 flags, bool check_mtu)
5501 {
5502 struct in6_addr *src = (struct in6_addr *) params->ipv6_src;
5503 struct in6_addr *dst = (struct in6_addr *) params->ipv6_dst;
5504 struct fib6_result res = {};
5505 struct neighbour *neigh;
5506 struct net_device *dev;
5507 struct inet6_dev *idev;
5508 struct flowi6 fl6;
5509 int strict = 0;
5510 int oif, err;
5511 u32 mtu = 0;
5512
5513 /* link local addresses are never forwarded */
5514 if (rt6_need_strict(dst) || rt6_need_strict(src))
5515 return BPF_FIB_LKUP_RET_NOT_FWDED;
5516
5517 dev = dev_get_by_index_rcu(net, params->ifindex);
5518 if (unlikely(!dev))
5519 return -ENODEV;
5520
5521 idev = __in6_dev_get_safely(dev);
5522 if (unlikely(!idev || !idev->cnf.forwarding))
5523 return BPF_FIB_LKUP_RET_FWD_DISABLED;
5524
5525 if (flags & BPF_FIB_LOOKUP_OUTPUT) {
5526 fl6.flowi6_iif = 1;
5527 oif = fl6.flowi6_oif = params->ifindex;
5528 } else {
5529 oif = fl6.flowi6_iif = params->ifindex;
5530 fl6.flowi6_oif = 0;
5531 strict = RT6_LOOKUP_F_HAS_SADDR;
5532 }
5533 fl6.flowlabel = params->flowinfo;
5534 fl6.flowi6_scope = 0;
5535 fl6.flowi6_flags = 0;
5536 fl6.mp_hash = 0;
5537
5538 fl6.flowi6_proto = params->l4_protocol;
5539 fl6.daddr = *dst;
5540 fl6.saddr = *src;
5541 fl6.fl6_sport = params->sport;
5542 fl6.fl6_dport = params->dport;
5543
5544 if (flags & BPF_FIB_LOOKUP_DIRECT) {
5545 u32 tbid = l3mdev_fib_table_rcu(dev) ? : RT_TABLE_MAIN;
5546 struct fib6_table *tb;
5547
5548 tb = ipv6_stub->fib6_get_table(net, tbid);
5549 if (unlikely(!tb))
5550 return BPF_FIB_LKUP_RET_NOT_FWDED;
5551
5552 err = ipv6_stub->fib6_table_lookup(net, tb, oif, &fl6, &res,
5553 strict);
5554 } else {
5555 fl6.flowi6_mark = 0;
5556 fl6.flowi6_secid = 0;
5557 fl6.flowi6_tun_key.tun_id = 0;
5558 fl6.flowi6_uid = sock_net_uid(net, NULL);
5559
5560 err = ipv6_stub->fib6_lookup(net, oif, &fl6, &res, strict);
5561 }
5562
5563 if (unlikely(err || IS_ERR_OR_NULL(res.f6i) ||
5564 res.f6i == net->ipv6.fib6_null_entry))
5565 return BPF_FIB_LKUP_RET_NOT_FWDED;
5566
5567 switch (res.fib6_type) {
5568 /* only unicast is forwarded */
5569 case RTN_UNICAST:
5570 break;
5571 case RTN_BLACKHOLE:
5572 return BPF_FIB_LKUP_RET_BLACKHOLE;
5573 case RTN_UNREACHABLE:
5574 return BPF_FIB_LKUP_RET_UNREACHABLE;
5575 case RTN_PROHIBIT:
5576 return BPF_FIB_LKUP_RET_PROHIBIT;
5577 default:
5578 return BPF_FIB_LKUP_RET_NOT_FWDED;
5579 }
5580
5581 ipv6_stub->fib6_select_path(net, &res, &fl6, fl6.flowi6_oif,
5582 fl6.flowi6_oif != 0, NULL, strict);
5583
5584 if (check_mtu) {
5585 mtu = ipv6_stub->ip6_mtu_from_fib6(&res, dst, src);
5586 if (params->tot_len > mtu) {
5587 params->mtu_result = mtu; /* union with tot_len */
5588 return BPF_FIB_LKUP_RET_FRAG_NEEDED;
5589 }
5590 }
5591
5592 if (res.nh->fib_nh_lws)
5593 return BPF_FIB_LKUP_RET_UNSUPP_LWT;
5594
5595 if (res.nh->fib_nh_gw_family)
5596 *dst = res.nh->fib_nh_gw6;
5597
5598 dev = res.nh->fib_nh_dev;
5599 params->rt_metric = res.f6i->fib6_metric;
5600 params->ifindex = dev->ifindex;
5601
5602 /* xdp and cls_bpf programs are run in RCU-bh so rcu_read_lock_bh is
5603 * not needed here.
5604 */
5605 neigh = __ipv6_neigh_lookup_noref_stub(dev, dst);
5606 if (!neigh)
5607 return BPF_FIB_LKUP_RET_NO_NEIGH;
5608
5609 return bpf_fib_set_fwd_params(params, neigh, dev, mtu);
5610 }
5611 #endif
5612
BPF_CALL_4(bpf_xdp_fib_lookup,struct xdp_buff *,ctx,struct bpf_fib_lookup *,params,int,plen,u32,flags)5613 BPF_CALL_4(bpf_xdp_fib_lookup, struct xdp_buff *, ctx,
5614 struct bpf_fib_lookup *, params, int, plen, u32, flags)
5615 {
5616 if (plen < sizeof(*params))
5617 return -EINVAL;
5618
5619 if (flags & ~(BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_OUTPUT))
5620 return -EINVAL;
5621
5622 switch (params->family) {
5623 #if IS_ENABLED(CONFIG_INET)
5624 case AF_INET:
5625 return bpf_ipv4_fib_lookup(dev_net(ctx->rxq->dev), params,
5626 flags, true);
5627 #endif
5628 #if IS_ENABLED(CONFIG_IPV6)
5629 case AF_INET6:
5630 return bpf_ipv6_fib_lookup(dev_net(ctx->rxq->dev), params,
5631 flags, true);
5632 #endif
5633 }
5634 return -EAFNOSUPPORT;
5635 }
5636
5637 static const struct bpf_func_proto bpf_xdp_fib_lookup_proto = {
5638 .func = bpf_xdp_fib_lookup,
5639 .gpl_only = true,
5640 .ret_type = RET_INTEGER,
5641 .arg1_type = ARG_PTR_TO_CTX,
5642 .arg2_type = ARG_PTR_TO_MEM,
5643 .arg3_type = ARG_CONST_SIZE,
5644 .arg4_type = ARG_ANYTHING,
5645 };
5646
BPF_CALL_4(bpf_skb_fib_lookup,struct sk_buff *,skb,struct bpf_fib_lookup *,params,int,plen,u32,flags)5647 BPF_CALL_4(bpf_skb_fib_lookup, struct sk_buff *, skb,
5648 struct bpf_fib_lookup *, params, int, plen, u32, flags)
5649 {
5650 struct net *net = dev_net(skb->dev);
5651 int rc = -EAFNOSUPPORT;
5652 bool check_mtu = false;
5653
5654 if (plen < sizeof(*params))
5655 return -EINVAL;
5656
5657 if (flags & ~(BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_OUTPUT))
5658 return -EINVAL;
5659
5660 if (params->tot_len)
5661 check_mtu = true;
5662
5663 switch (params->family) {
5664 #if IS_ENABLED(CONFIG_INET)
5665 case AF_INET:
5666 rc = bpf_ipv4_fib_lookup(net, params, flags, check_mtu);
5667 break;
5668 #endif
5669 #if IS_ENABLED(CONFIG_IPV6)
5670 case AF_INET6:
5671 rc = bpf_ipv6_fib_lookup(net, params, flags, check_mtu);
5672 break;
5673 #endif
5674 }
5675
5676 if (rc == BPF_FIB_LKUP_RET_SUCCESS && !check_mtu) {
5677 struct net_device *dev;
5678
5679 /* When tot_len isn't provided by user, check skb
5680 * against MTU of FIB lookup resulting net_device
5681 */
5682 dev = dev_get_by_index_rcu(net, params->ifindex);
5683 if (!is_skb_forwardable(dev, skb))
5684 rc = BPF_FIB_LKUP_RET_FRAG_NEEDED;
5685
5686 params->mtu_result = dev->mtu; /* union with tot_len */
5687 }
5688
5689 return rc;
5690 }
5691
5692 static const struct bpf_func_proto bpf_skb_fib_lookup_proto = {
5693 .func = bpf_skb_fib_lookup,
5694 .gpl_only = true,
5695 .ret_type = RET_INTEGER,
5696 .arg1_type = ARG_PTR_TO_CTX,
5697 .arg2_type = ARG_PTR_TO_MEM,
5698 .arg3_type = ARG_CONST_SIZE,
5699 .arg4_type = ARG_ANYTHING,
5700 };
5701
__dev_via_ifindex(struct net_device * dev_curr,u32 ifindex)5702 static struct net_device *__dev_via_ifindex(struct net_device *dev_curr,
5703 u32 ifindex)
5704 {
5705 struct net *netns = dev_net(dev_curr);
5706
5707 /* Non-redirect use-cases can use ifindex=0 and save ifindex lookup */
5708 if (ifindex == 0)
5709 return dev_curr;
5710
5711 return dev_get_by_index_rcu(netns, ifindex);
5712 }
5713
BPF_CALL_5(bpf_skb_check_mtu,struct sk_buff *,skb,u32,ifindex,u32 *,mtu_len,s32,len_diff,u64,flags)5714 BPF_CALL_5(bpf_skb_check_mtu, struct sk_buff *, skb,
5715 u32, ifindex, u32 *, mtu_len, s32, len_diff, u64, flags)
5716 {
5717 int ret = BPF_MTU_CHK_RET_FRAG_NEEDED;
5718 struct net_device *dev = skb->dev;
5719 int skb_len, dev_len;
5720 int mtu;
5721
5722 if (unlikely(flags & ~(BPF_MTU_CHK_SEGS)))
5723 return -EINVAL;
5724
5725 if (unlikely(flags & BPF_MTU_CHK_SEGS && (len_diff || *mtu_len)))
5726 return -EINVAL;
5727
5728 dev = __dev_via_ifindex(dev, ifindex);
5729 if (unlikely(!dev))
5730 return -ENODEV;
5731
5732 mtu = READ_ONCE(dev->mtu);
5733
5734 dev_len = mtu + dev->hard_header_len;
5735
5736 /* If set use *mtu_len as input, L3 as iph->tot_len (like fib_lookup) */
5737 skb_len = *mtu_len ? *mtu_len + dev->hard_header_len : skb->len;
5738
5739 skb_len += len_diff; /* minus result pass check */
5740 if (skb_len <= dev_len) {
5741 ret = BPF_MTU_CHK_RET_SUCCESS;
5742 goto out;
5743 }
5744 /* At this point, skb->len exceed MTU, but as it include length of all
5745 * segments, it can still be below MTU. The SKB can possibly get
5746 * re-segmented in transmit path (see validate_xmit_skb). Thus, user
5747 * must choose if segs are to be MTU checked.
5748 */
5749 if (skb_is_gso(skb)) {
5750 ret = BPF_MTU_CHK_RET_SUCCESS;
5751
5752 if (flags & BPF_MTU_CHK_SEGS &&
5753 !skb_gso_validate_network_len(skb, mtu))
5754 ret = BPF_MTU_CHK_RET_SEGS_TOOBIG;
5755 }
5756 out:
5757 /* BPF verifier guarantees valid pointer */
5758 *mtu_len = mtu;
5759
5760 return ret;
5761 }
5762
BPF_CALL_5(bpf_xdp_check_mtu,struct xdp_buff *,xdp,u32,ifindex,u32 *,mtu_len,s32,len_diff,u64,flags)5763 BPF_CALL_5(bpf_xdp_check_mtu, struct xdp_buff *, xdp,
5764 u32, ifindex, u32 *, mtu_len, s32, len_diff, u64, flags)
5765 {
5766 struct net_device *dev = xdp->rxq->dev;
5767 int xdp_len = xdp->data_end - xdp->data;
5768 int ret = BPF_MTU_CHK_RET_SUCCESS;
5769 int mtu, dev_len;
5770
5771 /* XDP variant doesn't support multi-buffer segment check (yet) */
5772 if (unlikely(flags))
5773 return -EINVAL;
5774
5775 dev = __dev_via_ifindex(dev, ifindex);
5776 if (unlikely(!dev))
5777 return -ENODEV;
5778
5779 mtu = READ_ONCE(dev->mtu);
5780
5781 /* Add L2-header as dev MTU is L3 size */
5782 dev_len = mtu + dev->hard_header_len;
5783
5784 /* Use *mtu_len as input, L3 as iph->tot_len (like fib_lookup) */
5785 if (*mtu_len)
5786 xdp_len = *mtu_len + dev->hard_header_len;
5787
5788 xdp_len += len_diff; /* minus result pass check */
5789 if (xdp_len > dev_len)
5790 ret = BPF_MTU_CHK_RET_FRAG_NEEDED;
5791
5792 /* BPF verifier guarantees valid pointer */
5793 *mtu_len = mtu;
5794
5795 return ret;
5796 }
5797
5798 static const struct bpf_func_proto bpf_skb_check_mtu_proto = {
5799 .func = bpf_skb_check_mtu,
5800 .gpl_only = true,
5801 .ret_type = RET_INTEGER,
5802 .arg1_type = ARG_PTR_TO_CTX,
5803 .arg2_type = ARG_ANYTHING,
5804 .arg3_type = ARG_PTR_TO_INT,
5805 .arg4_type = ARG_ANYTHING,
5806 .arg5_type = ARG_ANYTHING,
5807 };
5808
5809 static const struct bpf_func_proto bpf_xdp_check_mtu_proto = {
5810 .func = bpf_xdp_check_mtu,
5811 .gpl_only = true,
5812 .ret_type = RET_INTEGER,
5813 .arg1_type = ARG_PTR_TO_CTX,
5814 .arg2_type = ARG_ANYTHING,
5815 .arg3_type = ARG_PTR_TO_INT,
5816 .arg4_type = ARG_ANYTHING,
5817 .arg5_type = ARG_ANYTHING,
5818 };
5819
5820 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
bpf_push_seg6_encap(struct sk_buff * skb,u32 type,void * hdr,u32 len)5821 static int bpf_push_seg6_encap(struct sk_buff *skb, u32 type, void *hdr, u32 len)
5822 {
5823 int err;
5824 struct ipv6_sr_hdr *srh = (struct ipv6_sr_hdr *)hdr;
5825
5826 if (!seg6_validate_srh(srh, len, false))
5827 return -EINVAL;
5828
5829 switch (type) {
5830 case BPF_LWT_ENCAP_SEG6_INLINE:
5831 if (skb->protocol != htons(ETH_P_IPV6))
5832 return -EBADMSG;
5833
5834 err = seg6_do_srh_inline(skb, srh);
5835 break;
5836 case BPF_LWT_ENCAP_SEG6:
5837 skb_reset_inner_headers(skb);
5838 skb->encapsulation = 1;
5839 err = seg6_do_srh_encap(skb, srh, IPPROTO_IPV6);
5840 break;
5841 default:
5842 return -EINVAL;
5843 }
5844
5845 bpf_compute_data_pointers(skb);
5846 if (err)
5847 return err;
5848
5849 ipv6_hdr(skb)->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
5850 skb_set_transport_header(skb, sizeof(struct ipv6hdr));
5851
5852 return seg6_lookup_nexthop(skb, NULL, 0);
5853 }
5854 #endif /* CONFIG_IPV6_SEG6_BPF */
5855
5856 #if IS_ENABLED(CONFIG_LWTUNNEL_BPF)
bpf_push_ip_encap(struct sk_buff * skb,void * hdr,u32 len,bool ingress)5857 static int bpf_push_ip_encap(struct sk_buff *skb, void *hdr, u32 len,
5858 bool ingress)
5859 {
5860 return bpf_lwt_push_ip_encap(skb, hdr, len, ingress);
5861 }
5862 #endif
5863
BPF_CALL_4(bpf_lwt_in_push_encap,struct sk_buff *,skb,u32,type,void *,hdr,u32,len)5864 BPF_CALL_4(bpf_lwt_in_push_encap, struct sk_buff *, skb, u32, type, void *, hdr,
5865 u32, len)
5866 {
5867 switch (type) {
5868 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
5869 case BPF_LWT_ENCAP_SEG6:
5870 case BPF_LWT_ENCAP_SEG6_INLINE:
5871 return bpf_push_seg6_encap(skb, type, hdr, len);
5872 #endif
5873 #if IS_ENABLED(CONFIG_LWTUNNEL_BPF)
5874 case BPF_LWT_ENCAP_IP:
5875 return bpf_push_ip_encap(skb, hdr, len, true /* ingress */);
5876 #endif
5877 default:
5878 return -EINVAL;
5879 }
5880 }
5881
BPF_CALL_4(bpf_lwt_xmit_push_encap,struct sk_buff *,skb,u32,type,void *,hdr,u32,len)5882 BPF_CALL_4(bpf_lwt_xmit_push_encap, struct sk_buff *, skb, u32, type,
5883 void *, hdr, u32, len)
5884 {
5885 switch (type) {
5886 #if IS_ENABLED(CONFIG_LWTUNNEL_BPF)
5887 case BPF_LWT_ENCAP_IP:
5888 return bpf_push_ip_encap(skb, hdr, len, false /* egress */);
5889 #endif
5890 default:
5891 return -EINVAL;
5892 }
5893 }
5894
5895 static const struct bpf_func_proto bpf_lwt_in_push_encap_proto = {
5896 .func = bpf_lwt_in_push_encap,
5897 .gpl_only = false,
5898 .ret_type = RET_INTEGER,
5899 .arg1_type = ARG_PTR_TO_CTX,
5900 .arg2_type = ARG_ANYTHING,
5901 .arg3_type = ARG_PTR_TO_MEM,
5902 .arg4_type = ARG_CONST_SIZE
5903 };
5904
5905 static const struct bpf_func_proto bpf_lwt_xmit_push_encap_proto = {
5906 .func = bpf_lwt_xmit_push_encap,
5907 .gpl_only = false,
5908 .ret_type = RET_INTEGER,
5909 .arg1_type = ARG_PTR_TO_CTX,
5910 .arg2_type = ARG_ANYTHING,
5911 .arg3_type = ARG_PTR_TO_MEM,
5912 .arg4_type = ARG_CONST_SIZE
5913 };
5914
5915 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
BPF_CALL_4(bpf_lwt_seg6_store_bytes,struct sk_buff *,skb,u32,offset,const void *,from,u32,len)5916 BPF_CALL_4(bpf_lwt_seg6_store_bytes, struct sk_buff *, skb, u32, offset,
5917 const void *, from, u32, len)
5918 {
5919 struct seg6_bpf_srh_state *srh_state =
5920 this_cpu_ptr(&seg6_bpf_srh_states);
5921 struct ipv6_sr_hdr *srh = srh_state->srh;
5922 void *srh_tlvs, *srh_end, *ptr;
5923 int srhoff = 0;
5924
5925 if (srh == NULL)
5926 return -EINVAL;
5927
5928 srh_tlvs = (void *)((char *)srh + ((srh->first_segment + 1) << 4));
5929 srh_end = (void *)((char *)srh + sizeof(*srh) + srh_state->hdrlen);
5930
5931 ptr = skb->data + offset;
5932 if (ptr >= srh_tlvs && ptr + len <= srh_end)
5933 srh_state->valid = false;
5934 else if (ptr < (void *)&srh->flags ||
5935 ptr + len > (void *)&srh->segments)
5936 return -EFAULT;
5937
5938 if (unlikely(bpf_try_make_writable(skb, offset + len)))
5939 return -EFAULT;
5940 if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0)
5941 return -EINVAL;
5942 srh_state->srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
5943
5944 memcpy(skb->data + offset, from, len);
5945 return 0;
5946 }
5947
5948 static const struct bpf_func_proto bpf_lwt_seg6_store_bytes_proto = {
5949 .func = bpf_lwt_seg6_store_bytes,
5950 .gpl_only = false,
5951 .ret_type = RET_INTEGER,
5952 .arg1_type = ARG_PTR_TO_CTX,
5953 .arg2_type = ARG_ANYTHING,
5954 .arg3_type = ARG_PTR_TO_MEM,
5955 .arg4_type = ARG_CONST_SIZE
5956 };
5957
bpf_update_srh_state(struct sk_buff * skb)5958 static void bpf_update_srh_state(struct sk_buff *skb)
5959 {
5960 struct seg6_bpf_srh_state *srh_state =
5961 this_cpu_ptr(&seg6_bpf_srh_states);
5962 int srhoff = 0;
5963
5964 if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0) {
5965 srh_state->srh = NULL;
5966 } else {
5967 srh_state->srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
5968 srh_state->hdrlen = srh_state->srh->hdrlen << 3;
5969 srh_state->valid = true;
5970 }
5971 }
5972
BPF_CALL_4(bpf_lwt_seg6_action,struct sk_buff *,skb,u32,action,void *,param,u32,param_len)5973 BPF_CALL_4(bpf_lwt_seg6_action, struct sk_buff *, skb,
5974 u32, action, void *, param, u32, param_len)
5975 {
5976 struct seg6_bpf_srh_state *srh_state =
5977 this_cpu_ptr(&seg6_bpf_srh_states);
5978 int hdroff = 0;
5979 int err;
5980
5981 switch (action) {
5982 case SEG6_LOCAL_ACTION_END_X:
5983 if (!seg6_bpf_has_valid_srh(skb))
5984 return -EBADMSG;
5985 if (param_len != sizeof(struct in6_addr))
5986 return -EINVAL;
5987 return seg6_lookup_nexthop(skb, (struct in6_addr *)param, 0);
5988 case SEG6_LOCAL_ACTION_END_T:
5989 if (!seg6_bpf_has_valid_srh(skb))
5990 return -EBADMSG;
5991 if (param_len != sizeof(int))
5992 return -EINVAL;
5993 return seg6_lookup_nexthop(skb, NULL, *(int *)param);
5994 case SEG6_LOCAL_ACTION_END_DT6:
5995 if (!seg6_bpf_has_valid_srh(skb))
5996 return -EBADMSG;
5997 if (param_len != sizeof(int))
5998 return -EINVAL;
5999
6000 if (ipv6_find_hdr(skb, &hdroff, IPPROTO_IPV6, NULL, NULL) < 0)
6001 return -EBADMSG;
6002 if (!pskb_pull(skb, hdroff))
6003 return -EBADMSG;
6004
6005 skb_postpull_rcsum(skb, skb_network_header(skb), hdroff);
6006 skb_reset_network_header(skb);
6007 skb_reset_transport_header(skb);
6008 skb->encapsulation = 0;
6009
6010 bpf_compute_data_pointers(skb);
6011 bpf_update_srh_state(skb);
6012 return seg6_lookup_nexthop(skb, NULL, *(int *)param);
6013 case SEG6_LOCAL_ACTION_END_B6:
6014 if (srh_state->srh && !seg6_bpf_has_valid_srh(skb))
6015 return -EBADMSG;
6016 err = bpf_push_seg6_encap(skb, BPF_LWT_ENCAP_SEG6_INLINE,
6017 param, param_len);
6018 if (!err)
6019 bpf_update_srh_state(skb);
6020
6021 return err;
6022 case SEG6_LOCAL_ACTION_END_B6_ENCAP:
6023 if (srh_state->srh && !seg6_bpf_has_valid_srh(skb))
6024 return -EBADMSG;
6025 err = bpf_push_seg6_encap(skb, BPF_LWT_ENCAP_SEG6,
6026 param, param_len);
6027 if (!err)
6028 bpf_update_srh_state(skb);
6029
6030 return err;
6031 default:
6032 return -EINVAL;
6033 }
6034 }
6035
6036 static const struct bpf_func_proto bpf_lwt_seg6_action_proto = {
6037 .func = bpf_lwt_seg6_action,
6038 .gpl_only = false,
6039 .ret_type = RET_INTEGER,
6040 .arg1_type = ARG_PTR_TO_CTX,
6041 .arg2_type = ARG_ANYTHING,
6042 .arg3_type = ARG_PTR_TO_MEM,
6043 .arg4_type = ARG_CONST_SIZE
6044 };
6045
BPF_CALL_3(bpf_lwt_seg6_adjust_srh,struct sk_buff *,skb,u32,offset,s32,len)6046 BPF_CALL_3(bpf_lwt_seg6_adjust_srh, struct sk_buff *, skb, u32, offset,
6047 s32, len)
6048 {
6049 struct seg6_bpf_srh_state *srh_state =
6050 this_cpu_ptr(&seg6_bpf_srh_states);
6051 struct ipv6_sr_hdr *srh = srh_state->srh;
6052 void *srh_end, *srh_tlvs, *ptr;
6053 struct ipv6hdr *hdr;
6054 int srhoff = 0;
6055 int ret;
6056
6057 if (unlikely(srh == NULL))
6058 return -EINVAL;
6059
6060 srh_tlvs = (void *)((unsigned char *)srh + sizeof(*srh) +
6061 ((srh->first_segment + 1) << 4));
6062 srh_end = (void *)((unsigned char *)srh + sizeof(*srh) +
6063 srh_state->hdrlen);
6064 ptr = skb->data + offset;
6065
6066 if (unlikely(ptr < srh_tlvs || ptr > srh_end))
6067 return -EFAULT;
6068 if (unlikely(len < 0 && (void *)((char *)ptr - len) > srh_end))
6069 return -EFAULT;
6070
6071 if (len > 0) {
6072 ret = skb_cow_head(skb, len);
6073 if (unlikely(ret < 0))
6074 return ret;
6075
6076 ret = bpf_skb_net_hdr_push(skb, offset, len);
6077 } else {
6078 ret = bpf_skb_net_hdr_pop(skb, offset, -1 * len);
6079 }
6080
6081 bpf_compute_data_pointers(skb);
6082 if (unlikely(ret < 0))
6083 return ret;
6084
6085 hdr = (struct ipv6hdr *)skb->data;
6086 hdr->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
6087
6088 if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0)
6089 return -EINVAL;
6090 srh_state->srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
6091 srh_state->hdrlen += len;
6092 srh_state->valid = false;
6093 return 0;
6094 }
6095
6096 static const struct bpf_func_proto bpf_lwt_seg6_adjust_srh_proto = {
6097 .func = bpf_lwt_seg6_adjust_srh,
6098 .gpl_only = false,
6099 .ret_type = RET_INTEGER,
6100 .arg1_type = ARG_PTR_TO_CTX,
6101 .arg2_type = ARG_ANYTHING,
6102 .arg3_type = ARG_ANYTHING,
6103 };
6104 #endif /* CONFIG_IPV6_SEG6_BPF */
6105
6106 #ifdef CONFIG_INET
sk_lookup(struct net * net,struct bpf_sock_tuple * tuple,int dif,int sdif,u8 family,u8 proto)6107 static struct sock *sk_lookup(struct net *net, struct bpf_sock_tuple *tuple,
6108 int dif, int sdif, u8 family, u8 proto)
6109 {
6110 bool refcounted = false;
6111 struct sock *sk = NULL;
6112
6113 if (family == AF_INET) {
6114 __be32 src4 = tuple->ipv4.saddr;
6115 __be32 dst4 = tuple->ipv4.daddr;
6116
6117 if (proto == IPPROTO_TCP)
6118 sk = __inet_lookup(net, &tcp_hashinfo, NULL, 0,
6119 src4, tuple->ipv4.sport,
6120 dst4, tuple->ipv4.dport,
6121 dif, sdif, &refcounted);
6122 else
6123 sk = __udp4_lib_lookup(net, src4, tuple->ipv4.sport,
6124 dst4, tuple->ipv4.dport,
6125 dif, sdif, &udp_table, NULL);
6126 #if IS_ENABLED(CONFIG_IPV6)
6127 } else {
6128 struct in6_addr *src6 = (struct in6_addr *)&tuple->ipv6.saddr;
6129 struct in6_addr *dst6 = (struct in6_addr *)&tuple->ipv6.daddr;
6130
6131 if (proto == IPPROTO_TCP)
6132 sk = __inet6_lookup(net, &tcp_hashinfo, NULL, 0,
6133 src6, tuple->ipv6.sport,
6134 dst6, ntohs(tuple->ipv6.dport),
6135 dif, sdif, &refcounted);
6136 else if (likely(ipv6_bpf_stub))
6137 sk = ipv6_bpf_stub->udp6_lib_lookup(net,
6138 src6, tuple->ipv6.sport,
6139 dst6, tuple->ipv6.dport,
6140 dif, sdif,
6141 &udp_table, NULL);
6142 #endif
6143 }
6144
6145 if (unlikely(sk && !refcounted && !sock_flag(sk, SOCK_RCU_FREE))) {
6146 WARN_ONCE(1, "Found non-RCU, unreferenced socket!");
6147 sk = NULL;
6148 }
6149 return sk;
6150 }
6151
6152 /* bpf_skc_lookup performs the core lookup for different types of sockets,
6153 * taking a reference on the socket if it doesn't have the flag SOCK_RCU_FREE.
6154 * Returns the socket as an 'unsigned long' to simplify the casting in the
6155 * callers to satisfy BPF_CALL declarations.
6156 */
6157 static struct sock *
__bpf_skc_lookup(struct sk_buff * skb,struct bpf_sock_tuple * tuple,u32 len,struct net * caller_net,u32 ifindex,u8 proto,u64 netns_id,u64 flags)6158 __bpf_skc_lookup(struct sk_buff *skb, struct bpf_sock_tuple *tuple, u32 len,
6159 struct net *caller_net, u32 ifindex, u8 proto, u64 netns_id,
6160 u64 flags)
6161 {
6162 struct sock *sk = NULL;
6163 u8 family = AF_UNSPEC;
6164 struct net *net;
6165 int sdif;
6166
6167 if (len == sizeof(tuple->ipv4))
6168 family = AF_INET;
6169 else if (len == sizeof(tuple->ipv6))
6170 family = AF_INET6;
6171 else
6172 return NULL;
6173
6174 if (unlikely(family == AF_UNSPEC || flags ||
6175 !((s32)netns_id < 0 || netns_id <= S32_MAX)))
6176 goto out;
6177
6178 if (family == AF_INET)
6179 sdif = inet_sdif(skb);
6180 else
6181 sdif = inet6_sdif(skb);
6182
6183 if ((s32)netns_id < 0) {
6184 net = caller_net;
6185 sk = sk_lookup(net, tuple, ifindex, sdif, family, proto);
6186 } else {
6187 net = get_net_ns_by_id(caller_net, netns_id);
6188 if (unlikely(!net))
6189 goto out;
6190 sk = sk_lookup(net, tuple, ifindex, sdif, family, proto);
6191 put_net(net);
6192 }
6193
6194 out:
6195 return sk;
6196 }
6197
6198 static struct sock *
__bpf_sk_lookup(struct sk_buff * skb,struct bpf_sock_tuple * tuple,u32 len,struct net * caller_net,u32 ifindex,u8 proto,u64 netns_id,u64 flags)6199 __bpf_sk_lookup(struct sk_buff *skb, struct bpf_sock_tuple *tuple, u32 len,
6200 struct net *caller_net, u32 ifindex, u8 proto, u64 netns_id,
6201 u64 flags)
6202 {
6203 struct sock *sk = __bpf_skc_lookup(skb, tuple, len, caller_net,
6204 ifindex, proto, netns_id, flags);
6205
6206 if (sk) {
6207 sk = sk_to_full_sk(sk);
6208 if (!sk_fullsock(sk)) {
6209 sock_gen_put(sk);
6210 return NULL;
6211 }
6212 }
6213
6214 return sk;
6215 }
6216
6217 static struct sock *
bpf_skc_lookup(struct sk_buff * skb,struct bpf_sock_tuple * tuple,u32 len,u8 proto,u64 netns_id,u64 flags)6218 bpf_skc_lookup(struct sk_buff *skb, struct bpf_sock_tuple *tuple, u32 len,
6219 u8 proto, u64 netns_id, u64 flags)
6220 {
6221 struct net *caller_net;
6222 int ifindex;
6223
6224 if (skb->dev) {
6225 caller_net = dev_net(skb->dev);
6226 ifindex = skb->dev->ifindex;
6227 } else {
6228 caller_net = sock_net(skb->sk);
6229 ifindex = 0;
6230 }
6231
6232 return __bpf_skc_lookup(skb, tuple, len, caller_net, ifindex, proto,
6233 netns_id, flags);
6234 }
6235
6236 static struct sock *
bpf_sk_lookup(struct sk_buff * skb,struct bpf_sock_tuple * tuple,u32 len,u8 proto,u64 netns_id,u64 flags)6237 bpf_sk_lookup(struct sk_buff *skb, struct bpf_sock_tuple *tuple, u32 len,
6238 u8 proto, u64 netns_id, u64 flags)
6239 {
6240 struct sock *sk = bpf_skc_lookup(skb, tuple, len, proto, netns_id,
6241 flags);
6242
6243 if (sk) {
6244 sk = sk_to_full_sk(sk);
6245 if (!sk_fullsock(sk)) {
6246 sock_gen_put(sk);
6247 return NULL;
6248 }
6249 }
6250
6251 return sk;
6252 }
6253
BPF_CALL_5(bpf_skc_lookup_tcp,struct sk_buff *,skb,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)6254 BPF_CALL_5(bpf_skc_lookup_tcp, struct sk_buff *, skb,
6255 struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6256 {
6257 return (unsigned long)bpf_skc_lookup(skb, tuple, len, IPPROTO_TCP,
6258 netns_id, flags);
6259 }
6260
6261 static const struct bpf_func_proto bpf_skc_lookup_tcp_proto = {
6262 .func = bpf_skc_lookup_tcp,
6263 .gpl_only = false,
6264 .pkt_access = true,
6265 .ret_type = RET_PTR_TO_SOCK_COMMON_OR_NULL,
6266 .arg1_type = ARG_PTR_TO_CTX,
6267 .arg2_type = ARG_PTR_TO_MEM,
6268 .arg3_type = ARG_CONST_SIZE,
6269 .arg4_type = ARG_ANYTHING,
6270 .arg5_type = ARG_ANYTHING,
6271 };
6272
BPF_CALL_5(bpf_sk_lookup_tcp,struct sk_buff *,skb,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)6273 BPF_CALL_5(bpf_sk_lookup_tcp, struct sk_buff *, skb,
6274 struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6275 {
6276 return (unsigned long)bpf_sk_lookup(skb, tuple, len, IPPROTO_TCP,
6277 netns_id, flags);
6278 }
6279
6280 static const struct bpf_func_proto bpf_sk_lookup_tcp_proto = {
6281 .func = bpf_sk_lookup_tcp,
6282 .gpl_only = false,
6283 .pkt_access = true,
6284 .ret_type = RET_PTR_TO_SOCKET_OR_NULL,
6285 .arg1_type = ARG_PTR_TO_CTX,
6286 .arg2_type = ARG_PTR_TO_MEM,
6287 .arg3_type = ARG_CONST_SIZE,
6288 .arg4_type = ARG_ANYTHING,
6289 .arg5_type = ARG_ANYTHING,
6290 };
6291
BPF_CALL_5(bpf_sk_lookup_udp,struct sk_buff *,skb,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)6292 BPF_CALL_5(bpf_sk_lookup_udp, struct sk_buff *, skb,
6293 struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6294 {
6295 return (unsigned long)bpf_sk_lookup(skb, tuple, len, IPPROTO_UDP,
6296 netns_id, flags);
6297 }
6298
6299 static const struct bpf_func_proto bpf_sk_lookup_udp_proto = {
6300 .func = bpf_sk_lookup_udp,
6301 .gpl_only = false,
6302 .pkt_access = true,
6303 .ret_type = RET_PTR_TO_SOCKET_OR_NULL,
6304 .arg1_type = ARG_PTR_TO_CTX,
6305 .arg2_type = ARG_PTR_TO_MEM,
6306 .arg3_type = ARG_CONST_SIZE,
6307 .arg4_type = ARG_ANYTHING,
6308 .arg5_type = ARG_ANYTHING,
6309 };
6310
BPF_CALL_1(bpf_sk_release,struct sock *,sk)6311 BPF_CALL_1(bpf_sk_release, struct sock *, sk)
6312 {
6313 if (sk && sk_is_refcounted(sk))
6314 sock_gen_put(sk);
6315 return 0;
6316 }
6317
6318 static const struct bpf_func_proto bpf_sk_release_proto = {
6319 .func = bpf_sk_release,
6320 .gpl_only = false,
6321 .ret_type = RET_INTEGER,
6322 .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
6323 };
6324
BPF_CALL_5(bpf_xdp_sk_lookup_udp,struct xdp_buff *,ctx,struct bpf_sock_tuple *,tuple,u32,len,u32,netns_id,u64,flags)6325 BPF_CALL_5(bpf_xdp_sk_lookup_udp, struct xdp_buff *, ctx,
6326 struct bpf_sock_tuple *, tuple, u32, len, u32, netns_id, u64, flags)
6327 {
6328 struct net *caller_net = dev_net(ctx->rxq->dev);
6329 int ifindex = ctx->rxq->dev->ifindex;
6330
6331 return (unsigned long)__bpf_sk_lookup(NULL, tuple, len, caller_net,
6332 ifindex, IPPROTO_UDP, netns_id,
6333 flags);
6334 }
6335
6336 static const struct bpf_func_proto bpf_xdp_sk_lookup_udp_proto = {
6337 .func = bpf_xdp_sk_lookup_udp,
6338 .gpl_only = false,
6339 .pkt_access = true,
6340 .ret_type = RET_PTR_TO_SOCKET_OR_NULL,
6341 .arg1_type = ARG_PTR_TO_CTX,
6342 .arg2_type = ARG_PTR_TO_MEM,
6343 .arg3_type = ARG_CONST_SIZE,
6344 .arg4_type = ARG_ANYTHING,
6345 .arg5_type = ARG_ANYTHING,
6346 };
6347
BPF_CALL_5(bpf_xdp_skc_lookup_tcp,struct xdp_buff *,ctx,struct bpf_sock_tuple *,tuple,u32,len,u32,netns_id,u64,flags)6348 BPF_CALL_5(bpf_xdp_skc_lookup_tcp, struct xdp_buff *, ctx,
6349 struct bpf_sock_tuple *, tuple, u32, len, u32, netns_id, u64, flags)
6350 {
6351 struct net *caller_net = dev_net(ctx->rxq->dev);
6352 int ifindex = ctx->rxq->dev->ifindex;
6353
6354 return (unsigned long)__bpf_skc_lookup(NULL, tuple, len, caller_net,
6355 ifindex, IPPROTO_TCP, netns_id,
6356 flags);
6357 }
6358
6359 static const struct bpf_func_proto bpf_xdp_skc_lookup_tcp_proto = {
6360 .func = bpf_xdp_skc_lookup_tcp,
6361 .gpl_only = false,
6362 .pkt_access = true,
6363 .ret_type = RET_PTR_TO_SOCK_COMMON_OR_NULL,
6364 .arg1_type = ARG_PTR_TO_CTX,
6365 .arg2_type = ARG_PTR_TO_MEM,
6366 .arg3_type = ARG_CONST_SIZE,
6367 .arg4_type = ARG_ANYTHING,
6368 .arg5_type = ARG_ANYTHING,
6369 };
6370
BPF_CALL_5(bpf_xdp_sk_lookup_tcp,struct xdp_buff *,ctx,struct bpf_sock_tuple *,tuple,u32,len,u32,netns_id,u64,flags)6371 BPF_CALL_5(bpf_xdp_sk_lookup_tcp, struct xdp_buff *, ctx,
6372 struct bpf_sock_tuple *, tuple, u32, len, u32, netns_id, u64, flags)
6373 {
6374 struct net *caller_net = dev_net(ctx->rxq->dev);
6375 int ifindex = ctx->rxq->dev->ifindex;
6376
6377 return (unsigned long)__bpf_sk_lookup(NULL, tuple, len, caller_net,
6378 ifindex, IPPROTO_TCP, netns_id,
6379 flags);
6380 }
6381
6382 static const struct bpf_func_proto bpf_xdp_sk_lookup_tcp_proto = {
6383 .func = bpf_xdp_sk_lookup_tcp,
6384 .gpl_only = false,
6385 .pkt_access = true,
6386 .ret_type = RET_PTR_TO_SOCKET_OR_NULL,
6387 .arg1_type = ARG_PTR_TO_CTX,
6388 .arg2_type = ARG_PTR_TO_MEM,
6389 .arg3_type = ARG_CONST_SIZE,
6390 .arg4_type = ARG_ANYTHING,
6391 .arg5_type = ARG_ANYTHING,
6392 };
6393
BPF_CALL_5(bpf_sock_addr_skc_lookup_tcp,struct bpf_sock_addr_kern *,ctx,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)6394 BPF_CALL_5(bpf_sock_addr_skc_lookup_tcp, struct bpf_sock_addr_kern *, ctx,
6395 struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6396 {
6397 return (unsigned long)__bpf_skc_lookup(NULL, tuple, len,
6398 sock_net(ctx->sk), 0,
6399 IPPROTO_TCP, netns_id, flags);
6400 }
6401
6402 static const struct bpf_func_proto bpf_sock_addr_skc_lookup_tcp_proto = {
6403 .func = bpf_sock_addr_skc_lookup_tcp,
6404 .gpl_only = false,
6405 .ret_type = RET_PTR_TO_SOCK_COMMON_OR_NULL,
6406 .arg1_type = ARG_PTR_TO_CTX,
6407 .arg2_type = ARG_PTR_TO_MEM,
6408 .arg3_type = ARG_CONST_SIZE,
6409 .arg4_type = ARG_ANYTHING,
6410 .arg5_type = ARG_ANYTHING,
6411 };
6412
BPF_CALL_5(bpf_sock_addr_sk_lookup_tcp,struct bpf_sock_addr_kern *,ctx,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)6413 BPF_CALL_5(bpf_sock_addr_sk_lookup_tcp, struct bpf_sock_addr_kern *, ctx,
6414 struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6415 {
6416 return (unsigned long)__bpf_sk_lookup(NULL, tuple, len,
6417 sock_net(ctx->sk), 0, IPPROTO_TCP,
6418 netns_id, flags);
6419 }
6420
6421 static const struct bpf_func_proto bpf_sock_addr_sk_lookup_tcp_proto = {
6422 .func = bpf_sock_addr_sk_lookup_tcp,
6423 .gpl_only = false,
6424 .ret_type = RET_PTR_TO_SOCKET_OR_NULL,
6425 .arg1_type = ARG_PTR_TO_CTX,
6426 .arg2_type = ARG_PTR_TO_MEM,
6427 .arg3_type = ARG_CONST_SIZE,
6428 .arg4_type = ARG_ANYTHING,
6429 .arg5_type = ARG_ANYTHING,
6430 };
6431
BPF_CALL_5(bpf_sock_addr_sk_lookup_udp,struct bpf_sock_addr_kern *,ctx,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)6432 BPF_CALL_5(bpf_sock_addr_sk_lookup_udp, struct bpf_sock_addr_kern *, ctx,
6433 struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6434 {
6435 return (unsigned long)__bpf_sk_lookup(NULL, tuple, len,
6436 sock_net(ctx->sk), 0, IPPROTO_UDP,
6437 netns_id, flags);
6438 }
6439
6440 static const struct bpf_func_proto bpf_sock_addr_sk_lookup_udp_proto = {
6441 .func = bpf_sock_addr_sk_lookup_udp,
6442 .gpl_only = false,
6443 .ret_type = RET_PTR_TO_SOCKET_OR_NULL,
6444 .arg1_type = ARG_PTR_TO_CTX,
6445 .arg2_type = ARG_PTR_TO_MEM,
6446 .arg3_type = ARG_CONST_SIZE,
6447 .arg4_type = ARG_ANYTHING,
6448 .arg5_type = ARG_ANYTHING,
6449 };
6450
bpf_tcp_sock_is_valid_access(int off,int size,enum bpf_access_type type,struct bpf_insn_access_aux * info)6451 bool bpf_tcp_sock_is_valid_access(int off, int size, enum bpf_access_type type,
6452 struct bpf_insn_access_aux *info)
6453 {
6454 if (off < 0 || off >= offsetofend(struct bpf_tcp_sock,
6455 icsk_retransmits))
6456 return false;
6457
6458 if (off % size != 0)
6459 return false;
6460
6461 switch (off) {
6462 case offsetof(struct bpf_tcp_sock, bytes_received):
6463 case offsetof(struct bpf_tcp_sock, bytes_acked):
6464 return size == sizeof(__u64);
6465 default:
6466 return size == sizeof(__u32);
6467 }
6468 }
6469
bpf_tcp_sock_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)6470 u32 bpf_tcp_sock_convert_ctx_access(enum bpf_access_type type,
6471 const struct bpf_insn *si,
6472 struct bpf_insn *insn_buf,
6473 struct bpf_prog *prog, u32 *target_size)
6474 {
6475 struct bpf_insn *insn = insn_buf;
6476
6477 #define BPF_TCP_SOCK_GET_COMMON(FIELD) \
6478 do { \
6479 BUILD_BUG_ON(sizeof_field(struct tcp_sock, FIELD) > \
6480 sizeof_field(struct bpf_tcp_sock, FIELD)); \
6481 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct tcp_sock, FIELD),\
6482 si->dst_reg, si->src_reg, \
6483 offsetof(struct tcp_sock, FIELD)); \
6484 } while (0)
6485
6486 #define BPF_INET_SOCK_GET_COMMON(FIELD) \
6487 do { \
6488 BUILD_BUG_ON(sizeof_field(struct inet_connection_sock, \
6489 FIELD) > \
6490 sizeof_field(struct bpf_tcp_sock, FIELD)); \
6491 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \
6492 struct inet_connection_sock, \
6493 FIELD), \
6494 si->dst_reg, si->src_reg, \
6495 offsetof( \
6496 struct inet_connection_sock, \
6497 FIELD)); \
6498 } while (0)
6499
6500 if (insn > insn_buf)
6501 return insn - insn_buf;
6502
6503 switch (si->off) {
6504 case offsetof(struct bpf_tcp_sock, rtt_min):
6505 BUILD_BUG_ON(sizeof_field(struct tcp_sock, rtt_min) !=
6506 sizeof(struct minmax));
6507 BUILD_BUG_ON(sizeof(struct minmax) <
6508 sizeof(struct minmax_sample));
6509
6510 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
6511 offsetof(struct tcp_sock, rtt_min) +
6512 offsetof(struct minmax_sample, v));
6513 break;
6514 case offsetof(struct bpf_tcp_sock, snd_cwnd):
6515 BPF_TCP_SOCK_GET_COMMON(snd_cwnd);
6516 break;
6517 case offsetof(struct bpf_tcp_sock, srtt_us):
6518 BPF_TCP_SOCK_GET_COMMON(srtt_us);
6519 break;
6520 case offsetof(struct bpf_tcp_sock, snd_ssthresh):
6521 BPF_TCP_SOCK_GET_COMMON(snd_ssthresh);
6522 break;
6523 case offsetof(struct bpf_tcp_sock, rcv_nxt):
6524 BPF_TCP_SOCK_GET_COMMON(rcv_nxt);
6525 break;
6526 case offsetof(struct bpf_tcp_sock, snd_nxt):
6527 BPF_TCP_SOCK_GET_COMMON(snd_nxt);
6528 break;
6529 case offsetof(struct bpf_tcp_sock, snd_una):
6530 BPF_TCP_SOCK_GET_COMMON(snd_una);
6531 break;
6532 case offsetof(struct bpf_tcp_sock, mss_cache):
6533 BPF_TCP_SOCK_GET_COMMON(mss_cache);
6534 break;
6535 case offsetof(struct bpf_tcp_sock, ecn_flags):
6536 BPF_TCP_SOCK_GET_COMMON(ecn_flags);
6537 break;
6538 case offsetof(struct bpf_tcp_sock, rate_delivered):
6539 BPF_TCP_SOCK_GET_COMMON(rate_delivered);
6540 break;
6541 case offsetof(struct bpf_tcp_sock, rate_interval_us):
6542 BPF_TCP_SOCK_GET_COMMON(rate_interval_us);
6543 break;
6544 case offsetof(struct bpf_tcp_sock, packets_out):
6545 BPF_TCP_SOCK_GET_COMMON(packets_out);
6546 break;
6547 case offsetof(struct bpf_tcp_sock, retrans_out):
6548 BPF_TCP_SOCK_GET_COMMON(retrans_out);
6549 break;
6550 case offsetof(struct bpf_tcp_sock, total_retrans):
6551 BPF_TCP_SOCK_GET_COMMON(total_retrans);
6552 break;
6553 case offsetof(struct bpf_tcp_sock, segs_in):
6554 BPF_TCP_SOCK_GET_COMMON(segs_in);
6555 break;
6556 case offsetof(struct bpf_tcp_sock, data_segs_in):
6557 BPF_TCP_SOCK_GET_COMMON(data_segs_in);
6558 break;
6559 case offsetof(struct bpf_tcp_sock, segs_out):
6560 BPF_TCP_SOCK_GET_COMMON(segs_out);
6561 break;
6562 case offsetof(struct bpf_tcp_sock, data_segs_out):
6563 BPF_TCP_SOCK_GET_COMMON(data_segs_out);
6564 break;
6565 case offsetof(struct bpf_tcp_sock, lost_out):
6566 BPF_TCP_SOCK_GET_COMMON(lost_out);
6567 break;
6568 case offsetof(struct bpf_tcp_sock, sacked_out):
6569 BPF_TCP_SOCK_GET_COMMON(sacked_out);
6570 break;
6571 case offsetof(struct bpf_tcp_sock, bytes_received):
6572 BPF_TCP_SOCK_GET_COMMON(bytes_received);
6573 break;
6574 case offsetof(struct bpf_tcp_sock, bytes_acked):
6575 BPF_TCP_SOCK_GET_COMMON(bytes_acked);
6576 break;
6577 case offsetof(struct bpf_tcp_sock, dsack_dups):
6578 BPF_TCP_SOCK_GET_COMMON(dsack_dups);
6579 break;
6580 case offsetof(struct bpf_tcp_sock, delivered):
6581 BPF_TCP_SOCK_GET_COMMON(delivered);
6582 break;
6583 case offsetof(struct bpf_tcp_sock, delivered_ce):
6584 BPF_TCP_SOCK_GET_COMMON(delivered_ce);
6585 break;
6586 case offsetof(struct bpf_tcp_sock, icsk_retransmits):
6587 BPF_INET_SOCK_GET_COMMON(icsk_retransmits);
6588 break;
6589 }
6590
6591 return insn - insn_buf;
6592 }
6593
BPF_CALL_1(bpf_tcp_sock,struct sock *,sk)6594 BPF_CALL_1(bpf_tcp_sock, struct sock *, sk)
6595 {
6596 if (sk_fullsock(sk) && sk->sk_protocol == IPPROTO_TCP)
6597 return (unsigned long)sk;
6598
6599 return (unsigned long)NULL;
6600 }
6601
6602 const struct bpf_func_proto bpf_tcp_sock_proto = {
6603 .func = bpf_tcp_sock,
6604 .gpl_only = false,
6605 .ret_type = RET_PTR_TO_TCP_SOCK_OR_NULL,
6606 .arg1_type = ARG_PTR_TO_SOCK_COMMON,
6607 };
6608
BPF_CALL_1(bpf_get_listener_sock,struct sock *,sk)6609 BPF_CALL_1(bpf_get_listener_sock, struct sock *, sk)
6610 {
6611 sk = sk_to_full_sk(sk);
6612
6613 if (sk->sk_state == TCP_LISTEN && sock_flag(sk, SOCK_RCU_FREE))
6614 return (unsigned long)sk;
6615
6616 return (unsigned long)NULL;
6617 }
6618
6619 static const struct bpf_func_proto bpf_get_listener_sock_proto = {
6620 .func = bpf_get_listener_sock,
6621 .gpl_only = false,
6622 .ret_type = RET_PTR_TO_SOCKET_OR_NULL,
6623 .arg1_type = ARG_PTR_TO_SOCK_COMMON,
6624 };
6625
BPF_CALL_1(bpf_skb_ecn_set_ce,struct sk_buff *,skb)6626 BPF_CALL_1(bpf_skb_ecn_set_ce, struct sk_buff *, skb)
6627 {
6628 unsigned int iphdr_len;
6629
6630 switch (skb_protocol(skb, true)) {
6631 case cpu_to_be16(ETH_P_IP):
6632 iphdr_len = sizeof(struct iphdr);
6633 break;
6634 case cpu_to_be16(ETH_P_IPV6):
6635 iphdr_len = sizeof(struct ipv6hdr);
6636 break;
6637 default:
6638 return 0;
6639 }
6640
6641 if (skb_headlen(skb) < iphdr_len)
6642 return 0;
6643
6644 if (skb_cloned(skb) && !skb_clone_writable(skb, iphdr_len))
6645 return 0;
6646
6647 return INET_ECN_set_ce(skb);
6648 }
6649
bpf_xdp_sock_is_valid_access(int off,int size,enum bpf_access_type type,struct bpf_insn_access_aux * info)6650 bool bpf_xdp_sock_is_valid_access(int off, int size, enum bpf_access_type type,
6651 struct bpf_insn_access_aux *info)
6652 {
6653 if (off < 0 || off >= offsetofend(struct bpf_xdp_sock, queue_id))
6654 return false;
6655
6656 if (off % size != 0)
6657 return false;
6658
6659 switch (off) {
6660 default:
6661 return size == sizeof(__u32);
6662 }
6663 }
6664
bpf_xdp_sock_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)6665 u32 bpf_xdp_sock_convert_ctx_access(enum bpf_access_type type,
6666 const struct bpf_insn *si,
6667 struct bpf_insn *insn_buf,
6668 struct bpf_prog *prog, u32 *target_size)
6669 {
6670 struct bpf_insn *insn = insn_buf;
6671
6672 #define BPF_XDP_SOCK_GET(FIELD) \
6673 do { \
6674 BUILD_BUG_ON(sizeof_field(struct xdp_sock, FIELD) > \
6675 sizeof_field(struct bpf_xdp_sock, FIELD)); \
6676 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_sock, FIELD),\
6677 si->dst_reg, si->src_reg, \
6678 offsetof(struct xdp_sock, FIELD)); \
6679 } while (0)
6680
6681 switch (si->off) {
6682 case offsetof(struct bpf_xdp_sock, queue_id):
6683 BPF_XDP_SOCK_GET(queue_id);
6684 break;
6685 }
6686
6687 return insn - insn_buf;
6688 }
6689
6690 static const struct bpf_func_proto bpf_skb_ecn_set_ce_proto = {
6691 .func = bpf_skb_ecn_set_ce,
6692 .gpl_only = false,
6693 .ret_type = RET_INTEGER,
6694 .arg1_type = ARG_PTR_TO_CTX,
6695 };
6696
BPF_CALL_5(bpf_tcp_check_syncookie,struct sock *,sk,void *,iph,u32,iph_len,struct tcphdr *,th,u32,th_len)6697 BPF_CALL_5(bpf_tcp_check_syncookie, struct sock *, sk, void *, iph, u32, iph_len,
6698 struct tcphdr *, th, u32, th_len)
6699 {
6700 #ifdef CONFIG_SYN_COOKIES
6701 u32 cookie;
6702 int ret;
6703
6704 if (unlikely(!sk || th_len < sizeof(*th)))
6705 return -EINVAL;
6706
6707 /* sk_listener() allows TCP_NEW_SYN_RECV, which makes no sense here. */
6708 if (sk->sk_protocol != IPPROTO_TCP || sk->sk_state != TCP_LISTEN)
6709 return -EINVAL;
6710
6711 if (!sock_net(sk)->ipv4.sysctl_tcp_syncookies)
6712 return -EINVAL;
6713
6714 if (!th->ack || th->rst || th->syn)
6715 return -ENOENT;
6716
6717 if (tcp_synq_no_recent_overflow(sk))
6718 return -ENOENT;
6719
6720 cookie = ntohl(th->ack_seq) - 1;
6721
6722 switch (sk->sk_family) {
6723 case AF_INET:
6724 if (unlikely(iph_len < sizeof(struct iphdr)))
6725 return -EINVAL;
6726
6727 ret = __cookie_v4_check((struct iphdr *)iph, th, cookie);
6728 break;
6729
6730 #if IS_BUILTIN(CONFIG_IPV6)
6731 case AF_INET6:
6732 if (unlikely(iph_len < sizeof(struct ipv6hdr)))
6733 return -EINVAL;
6734
6735 ret = __cookie_v6_check((struct ipv6hdr *)iph, th, cookie);
6736 break;
6737 #endif /* CONFIG_IPV6 */
6738
6739 default:
6740 return -EPROTONOSUPPORT;
6741 }
6742
6743 if (ret > 0)
6744 return 0;
6745
6746 return -ENOENT;
6747 #else
6748 return -ENOTSUPP;
6749 #endif
6750 }
6751
6752 static const struct bpf_func_proto bpf_tcp_check_syncookie_proto = {
6753 .func = bpf_tcp_check_syncookie,
6754 .gpl_only = true,
6755 .pkt_access = true,
6756 .ret_type = RET_INTEGER,
6757 .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
6758 .arg2_type = ARG_PTR_TO_MEM,
6759 .arg3_type = ARG_CONST_SIZE,
6760 .arg4_type = ARG_PTR_TO_MEM,
6761 .arg5_type = ARG_CONST_SIZE,
6762 };
6763
BPF_CALL_5(bpf_tcp_gen_syncookie,struct sock *,sk,void *,iph,u32,iph_len,struct tcphdr *,th,u32,th_len)6764 BPF_CALL_5(bpf_tcp_gen_syncookie, struct sock *, sk, void *, iph, u32, iph_len,
6765 struct tcphdr *, th, u32, th_len)
6766 {
6767 #ifdef CONFIG_SYN_COOKIES
6768 u32 cookie;
6769 u16 mss;
6770
6771 if (unlikely(!sk || th_len < sizeof(*th) || th_len != th->doff * 4))
6772 return -EINVAL;
6773
6774 if (sk->sk_protocol != IPPROTO_TCP || sk->sk_state != TCP_LISTEN)
6775 return -EINVAL;
6776
6777 if (!sock_net(sk)->ipv4.sysctl_tcp_syncookies)
6778 return -ENOENT;
6779
6780 if (!th->syn || th->ack || th->fin || th->rst)
6781 return -EINVAL;
6782
6783 if (unlikely(iph_len < sizeof(struct iphdr)))
6784 return -EINVAL;
6785
6786 /* Both struct iphdr and struct ipv6hdr have the version field at the
6787 * same offset so we can cast to the shorter header (struct iphdr).
6788 */
6789 switch (((struct iphdr *)iph)->version) {
6790 case 4:
6791 if (sk->sk_family == AF_INET6 && sk->sk_ipv6only)
6792 return -EINVAL;
6793
6794 mss = tcp_v4_get_syncookie(sk, iph, th, &cookie);
6795 break;
6796
6797 #if IS_BUILTIN(CONFIG_IPV6)
6798 case 6:
6799 if (unlikely(iph_len < sizeof(struct ipv6hdr)))
6800 return -EINVAL;
6801
6802 if (sk->sk_family != AF_INET6)
6803 return -EINVAL;
6804
6805 mss = tcp_v6_get_syncookie(sk, iph, th, &cookie);
6806 break;
6807 #endif /* CONFIG_IPV6 */
6808
6809 default:
6810 return -EPROTONOSUPPORT;
6811 }
6812 if (mss == 0)
6813 return -ENOENT;
6814
6815 return cookie | ((u64)mss << 32);
6816 #else
6817 return -EOPNOTSUPP;
6818 #endif /* CONFIG_SYN_COOKIES */
6819 }
6820
6821 static const struct bpf_func_proto bpf_tcp_gen_syncookie_proto = {
6822 .func = bpf_tcp_gen_syncookie,
6823 .gpl_only = true, /* __cookie_v*_init_sequence() is GPL */
6824 .pkt_access = true,
6825 .ret_type = RET_INTEGER,
6826 .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
6827 .arg2_type = ARG_PTR_TO_MEM,
6828 .arg3_type = ARG_CONST_SIZE,
6829 .arg4_type = ARG_PTR_TO_MEM,
6830 .arg5_type = ARG_CONST_SIZE,
6831 };
6832
BPF_CALL_3(bpf_sk_assign,struct sk_buff *,skb,struct sock *,sk,u64,flags)6833 BPF_CALL_3(bpf_sk_assign, struct sk_buff *, skb, struct sock *, sk, u64, flags)
6834 {
6835 if (!sk || flags != 0)
6836 return -EINVAL;
6837 if (!skb_at_tc_ingress(skb))
6838 return -EOPNOTSUPP;
6839 if (unlikely(dev_net(skb->dev) != sock_net(sk)))
6840 return -ENETUNREACH;
6841 if (unlikely(sk_fullsock(sk) && sk->sk_reuseport))
6842 return -ESOCKTNOSUPPORT;
6843 if (sk_is_refcounted(sk) &&
6844 unlikely(!refcount_inc_not_zero(&sk->sk_refcnt)))
6845 return -ENOENT;
6846
6847 skb_orphan(skb);
6848 skb->sk = sk;
6849 skb->destructor = sock_pfree;
6850
6851 return 0;
6852 }
6853
6854 static const struct bpf_func_proto bpf_sk_assign_proto = {
6855 .func = bpf_sk_assign,
6856 .gpl_only = false,
6857 .ret_type = RET_INTEGER,
6858 .arg1_type = ARG_PTR_TO_CTX,
6859 .arg2_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
6860 .arg3_type = ARG_ANYTHING,
6861 };
6862
bpf_search_tcp_opt(const u8 * op,const u8 * opend,u8 search_kind,const u8 * magic,u8 magic_len,bool * eol)6863 static const u8 *bpf_search_tcp_opt(const u8 *op, const u8 *opend,
6864 u8 search_kind, const u8 *magic,
6865 u8 magic_len, bool *eol)
6866 {
6867 u8 kind, kind_len;
6868
6869 *eol = false;
6870
6871 while (op < opend) {
6872 kind = op[0];
6873
6874 if (kind == TCPOPT_EOL) {
6875 *eol = true;
6876 return ERR_PTR(-ENOMSG);
6877 } else if (kind == TCPOPT_NOP) {
6878 op++;
6879 continue;
6880 }
6881
6882 if (opend - op < 2 || opend - op < op[1] || op[1] < 2)
6883 /* Something is wrong in the received header.
6884 * Follow the TCP stack's tcp_parse_options()
6885 * and just bail here.
6886 */
6887 return ERR_PTR(-EFAULT);
6888
6889 kind_len = op[1];
6890 if (search_kind == kind) {
6891 if (!magic_len)
6892 return op;
6893
6894 if (magic_len > kind_len - 2)
6895 return ERR_PTR(-ENOMSG);
6896
6897 if (!memcmp(&op[2], magic, magic_len))
6898 return op;
6899 }
6900
6901 op += kind_len;
6902 }
6903
6904 return ERR_PTR(-ENOMSG);
6905 }
6906
BPF_CALL_4(bpf_sock_ops_load_hdr_opt,struct bpf_sock_ops_kern *,bpf_sock,void *,search_res,u32,len,u64,flags)6907 BPF_CALL_4(bpf_sock_ops_load_hdr_opt, struct bpf_sock_ops_kern *, bpf_sock,
6908 void *, search_res, u32, len, u64, flags)
6909 {
6910 bool eol, load_syn = flags & BPF_LOAD_HDR_OPT_TCP_SYN;
6911 const u8 *op, *opend, *magic, *search = search_res;
6912 u8 search_kind, search_len, copy_len, magic_len;
6913 int ret;
6914
6915 /* 2 byte is the minimal option len except TCPOPT_NOP and
6916 * TCPOPT_EOL which are useless for the bpf prog to learn
6917 * and this helper disallow loading them also.
6918 */
6919 if (len < 2 || flags & ~BPF_LOAD_HDR_OPT_TCP_SYN)
6920 return -EINVAL;
6921
6922 search_kind = search[0];
6923 search_len = search[1];
6924
6925 if (search_len > len || search_kind == TCPOPT_NOP ||
6926 search_kind == TCPOPT_EOL)
6927 return -EINVAL;
6928
6929 if (search_kind == TCPOPT_EXP || search_kind == 253) {
6930 /* 16 or 32 bit magic. +2 for kind and kind length */
6931 if (search_len != 4 && search_len != 6)
6932 return -EINVAL;
6933 magic = &search[2];
6934 magic_len = search_len - 2;
6935 } else {
6936 if (search_len)
6937 return -EINVAL;
6938 magic = NULL;
6939 magic_len = 0;
6940 }
6941
6942 if (load_syn) {
6943 ret = bpf_sock_ops_get_syn(bpf_sock, TCP_BPF_SYN, &op);
6944 if (ret < 0)
6945 return ret;
6946
6947 opend = op + ret;
6948 op += sizeof(struct tcphdr);
6949 } else {
6950 if (!bpf_sock->skb ||
6951 bpf_sock->op == BPF_SOCK_OPS_HDR_OPT_LEN_CB)
6952 /* This bpf_sock->op cannot call this helper */
6953 return -EPERM;
6954
6955 opend = bpf_sock->skb_data_end;
6956 op = bpf_sock->skb->data + sizeof(struct tcphdr);
6957 }
6958
6959 op = bpf_search_tcp_opt(op, opend, search_kind, magic, magic_len,
6960 &eol);
6961 if (IS_ERR(op))
6962 return PTR_ERR(op);
6963
6964 copy_len = op[1];
6965 ret = copy_len;
6966 if (copy_len > len) {
6967 ret = -ENOSPC;
6968 copy_len = len;
6969 }
6970
6971 memcpy(search_res, op, copy_len);
6972 return ret;
6973 }
6974
6975 static const struct bpf_func_proto bpf_sock_ops_load_hdr_opt_proto = {
6976 .func = bpf_sock_ops_load_hdr_opt,
6977 .gpl_only = false,
6978 .ret_type = RET_INTEGER,
6979 .arg1_type = ARG_PTR_TO_CTX,
6980 .arg2_type = ARG_PTR_TO_MEM,
6981 .arg3_type = ARG_CONST_SIZE,
6982 .arg4_type = ARG_ANYTHING,
6983 };
6984
BPF_CALL_4(bpf_sock_ops_store_hdr_opt,struct bpf_sock_ops_kern *,bpf_sock,const void *,from,u32,len,u64,flags)6985 BPF_CALL_4(bpf_sock_ops_store_hdr_opt, struct bpf_sock_ops_kern *, bpf_sock,
6986 const void *, from, u32, len, u64, flags)
6987 {
6988 u8 new_kind, new_kind_len, magic_len = 0, *opend;
6989 const u8 *op, *new_op, *magic = NULL;
6990 struct sk_buff *skb;
6991 bool eol;
6992
6993 if (bpf_sock->op != BPF_SOCK_OPS_WRITE_HDR_OPT_CB)
6994 return -EPERM;
6995
6996 if (len < 2 || flags)
6997 return -EINVAL;
6998
6999 new_op = from;
7000 new_kind = new_op[0];
7001 new_kind_len = new_op[1];
7002
7003 if (new_kind_len > len || new_kind == TCPOPT_NOP ||
7004 new_kind == TCPOPT_EOL)
7005 return -EINVAL;
7006
7007 if (new_kind_len > bpf_sock->remaining_opt_len)
7008 return -ENOSPC;
7009
7010 /* 253 is another experimental kind */
7011 if (new_kind == TCPOPT_EXP || new_kind == 253) {
7012 if (new_kind_len < 4)
7013 return -EINVAL;
7014 /* Match for the 2 byte magic also.
7015 * RFC 6994: the magic could be 2 or 4 bytes.
7016 * Hence, matching by 2 byte only is on the
7017 * conservative side but it is the right
7018 * thing to do for the 'search-for-duplication'
7019 * purpose.
7020 */
7021 magic = &new_op[2];
7022 magic_len = 2;
7023 }
7024
7025 /* Check for duplication */
7026 skb = bpf_sock->skb;
7027 op = skb->data + sizeof(struct tcphdr);
7028 opend = bpf_sock->skb_data_end;
7029
7030 op = bpf_search_tcp_opt(op, opend, new_kind, magic, magic_len,
7031 &eol);
7032 if (!IS_ERR(op))
7033 return -EEXIST;
7034
7035 if (PTR_ERR(op) != -ENOMSG)
7036 return PTR_ERR(op);
7037
7038 if (eol)
7039 /* The option has been ended. Treat it as no more
7040 * header option can be written.
7041 */
7042 return -ENOSPC;
7043
7044 /* No duplication found. Store the header option. */
7045 memcpy(opend, from, new_kind_len);
7046
7047 bpf_sock->remaining_opt_len -= new_kind_len;
7048 bpf_sock->skb_data_end += new_kind_len;
7049
7050 return 0;
7051 }
7052
7053 static const struct bpf_func_proto bpf_sock_ops_store_hdr_opt_proto = {
7054 .func = bpf_sock_ops_store_hdr_opt,
7055 .gpl_only = false,
7056 .ret_type = RET_INTEGER,
7057 .arg1_type = ARG_PTR_TO_CTX,
7058 .arg2_type = ARG_PTR_TO_MEM,
7059 .arg3_type = ARG_CONST_SIZE,
7060 .arg4_type = ARG_ANYTHING,
7061 };
7062
BPF_CALL_3(bpf_sock_ops_reserve_hdr_opt,struct bpf_sock_ops_kern *,bpf_sock,u32,len,u64,flags)7063 BPF_CALL_3(bpf_sock_ops_reserve_hdr_opt, struct bpf_sock_ops_kern *, bpf_sock,
7064 u32, len, u64, flags)
7065 {
7066 if (bpf_sock->op != BPF_SOCK_OPS_HDR_OPT_LEN_CB)
7067 return -EPERM;
7068
7069 if (flags || len < 2)
7070 return -EINVAL;
7071
7072 if (len > bpf_sock->remaining_opt_len)
7073 return -ENOSPC;
7074
7075 bpf_sock->remaining_opt_len -= len;
7076
7077 return 0;
7078 }
7079
7080 static const struct bpf_func_proto bpf_sock_ops_reserve_hdr_opt_proto = {
7081 .func = bpf_sock_ops_reserve_hdr_opt,
7082 .gpl_only = false,
7083 .ret_type = RET_INTEGER,
7084 .arg1_type = ARG_PTR_TO_CTX,
7085 .arg2_type = ARG_ANYTHING,
7086 .arg3_type = ARG_ANYTHING,
7087 };
7088
7089 #endif /* CONFIG_INET */
7090
bpf_helper_changes_pkt_data(void * func)7091 bool bpf_helper_changes_pkt_data(void *func)
7092 {
7093 if (func == bpf_skb_vlan_push ||
7094 func == bpf_skb_vlan_pop ||
7095 func == bpf_skb_store_bytes ||
7096 func == bpf_skb_change_proto ||
7097 func == bpf_skb_change_head ||
7098 func == sk_skb_change_head ||
7099 func == bpf_skb_change_tail ||
7100 func == sk_skb_change_tail ||
7101 func == bpf_skb_adjust_room ||
7102 func == sk_skb_adjust_room ||
7103 func == bpf_skb_pull_data ||
7104 func == sk_skb_pull_data ||
7105 func == bpf_clone_redirect ||
7106 func == bpf_l3_csum_replace ||
7107 func == bpf_l4_csum_replace ||
7108 func == bpf_xdp_adjust_head ||
7109 func == bpf_xdp_adjust_meta ||
7110 func == bpf_msg_pull_data ||
7111 func == bpf_msg_push_data ||
7112 func == bpf_msg_pop_data ||
7113 func == bpf_xdp_adjust_tail ||
7114 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
7115 func == bpf_lwt_seg6_store_bytes ||
7116 func == bpf_lwt_seg6_adjust_srh ||
7117 func == bpf_lwt_seg6_action ||
7118 #endif
7119 #ifdef CONFIG_INET
7120 func == bpf_sock_ops_store_hdr_opt ||
7121 #endif
7122 func == bpf_lwt_in_push_encap ||
7123 func == bpf_lwt_xmit_push_encap)
7124 return true;
7125
7126 return false;
7127 }
7128
7129 const struct bpf_func_proto bpf_event_output_data_proto __weak;
7130 const struct bpf_func_proto bpf_sk_storage_get_cg_sock_proto __weak;
7131
7132 static const struct bpf_func_proto *
sock_filter_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7133 sock_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7134 {
7135 switch (func_id) {
7136 /* inet and inet6 sockets are created in a process
7137 * context so there is always a valid uid/gid
7138 */
7139 case BPF_FUNC_get_current_uid_gid:
7140 return &bpf_get_current_uid_gid_proto;
7141 case BPF_FUNC_get_local_storage:
7142 return &bpf_get_local_storage_proto;
7143 case BPF_FUNC_get_socket_cookie:
7144 return &bpf_get_socket_cookie_sock_proto;
7145 case BPF_FUNC_get_netns_cookie:
7146 return &bpf_get_netns_cookie_sock_proto;
7147 case BPF_FUNC_perf_event_output:
7148 return &bpf_event_output_data_proto;
7149 case BPF_FUNC_get_current_pid_tgid:
7150 return &bpf_get_current_pid_tgid_proto;
7151 case BPF_FUNC_get_current_comm:
7152 return &bpf_get_current_comm_proto;
7153 #ifdef CONFIG_CGROUPS
7154 case BPF_FUNC_get_current_cgroup_id:
7155 return &bpf_get_current_cgroup_id_proto;
7156 case BPF_FUNC_get_current_ancestor_cgroup_id:
7157 return &bpf_get_current_ancestor_cgroup_id_proto;
7158 #endif
7159 #ifdef CONFIG_CGROUP_NET_CLASSID
7160 case BPF_FUNC_get_cgroup_classid:
7161 return &bpf_get_cgroup_classid_curr_proto;
7162 #endif
7163 case BPF_FUNC_sk_storage_get:
7164 return &bpf_sk_storage_get_cg_sock_proto;
7165 default:
7166 return bpf_base_func_proto(func_id);
7167 }
7168 }
7169
7170 static const struct bpf_func_proto *
sock_addr_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7171 sock_addr_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7172 {
7173 switch (func_id) {
7174 /* inet and inet6 sockets are created in a process
7175 * context so there is always a valid uid/gid
7176 */
7177 case BPF_FUNC_get_current_uid_gid:
7178 return &bpf_get_current_uid_gid_proto;
7179 case BPF_FUNC_bind:
7180 switch (prog->expected_attach_type) {
7181 case BPF_CGROUP_INET4_CONNECT:
7182 case BPF_CGROUP_INET6_CONNECT:
7183 return &bpf_bind_proto;
7184 default:
7185 return NULL;
7186 }
7187 case BPF_FUNC_get_socket_cookie:
7188 return &bpf_get_socket_cookie_sock_addr_proto;
7189 case BPF_FUNC_get_netns_cookie:
7190 return &bpf_get_netns_cookie_sock_addr_proto;
7191 case BPF_FUNC_get_local_storage:
7192 return &bpf_get_local_storage_proto;
7193 case BPF_FUNC_perf_event_output:
7194 return &bpf_event_output_data_proto;
7195 case BPF_FUNC_get_current_pid_tgid:
7196 return &bpf_get_current_pid_tgid_proto;
7197 case BPF_FUNC_get_current_comm:
7198 return &bpf_get_current_comm_proto;
7199 #ifdef CONFIG_CGROUPS
7200 case BPF_FUNC_get_current_cgroup_id:
7201 return &bpf_get_current_cgroup_id_proto;
7202 case BPF_FUNC_get_current_ancestor_cgroup_id:
7203 return &bpf_get_current_ancestor_cgroup_id_proto;
7204 #endif
7205 #ifdef CONFIG_CGROUP_NET_CLASSID
7206 case BPF_FUNC_get_cgroup_classid:
7207 return &bpf_get_cgroup_classid_curr_proto;
7208 #endif
7209 #ifdef CONFIG_INET
7210 case BPF_FUNC_sk_lookup_tcp:
7211 return &bpf_sock_addr_sk_lookup_tcp_proto;
7212 case BPF_FUNC_sk_lookup_udp:
7213 return &bpf_sock_addr_sk_lookup_udp_proto;
7214 case BPF_FUNC_sk_release:
7215 return &bpf_sk_release_proto;
7216 case BPF_FUNC_skc_lookup_tcp:
7217 return &bpf_sock_addr_skc_lookup_tcp_proto;
7218 #endif /* CONFIG_INET */
7219 case BPF_FUNC_sk_storage_get:
7220 return &bpf_sk_storage_get_proto;
7221 case BPF_FUNC_sk_storage_delete:
7222 return &bpf_sk_storage_delete_proto;
7223 case BPF_FUNC_setsockopt:
7224 switch (prog->expected_attach_type) {
7225 case BPF_CGROUP_INET4_BIND:
7226 case BPF_CGROUP_INET6_BIND:
7227 case BPF_CGROUP_INET4_CONNECT:
7228 case BPF_CGROUP_INET6_CONNECT:
7229 case BPF_CGROUP_UDP4_RECVMSG:
7230 case BPF_CGROUP_UDP6_RECVMSG:
7231 case BPF_CGROUP_UDP4_SENDMSG:
7232 case BPF_CGROUP_UDP6_SENDMSG:
7233 case BPF_CGROUP_INET4_GETPEERNAME:
7234 case BPF_CGROUP_INET6_GETPEERNAME:
7235 case BPF_CGROUP_INET4_GETSOCKNAME:
7236 case BPF_CGROUP_INET6_GETSOCKNAME:
7237 return &bpf_sock_addr_setsockopt_proto;
7238 default:
7239 return NULL;
7240 }
7241 case BPF_FUNC_getsockopt:
7242 switch (prog->expected_attach_type) {
7243 case BPF_CGROUP_INET4_BIND:
7244 case BPF_CGROUP_INET6_BIND:
7245 case BPF_CGROUP_INET4_CONNECT:
7246 case BPF_CGROUP_INET6_CONNECT:
7247 case BPF_CGROUP_UDP4_RECVMSG:
7248 case BPF_CGROUP_UDP6_RECVMSG:
7249 case BPF_CGROUP_UDP4_SENDMSG:
7250 case BPF_CGROUP_UDP6_SENDMSG:
7251 case BPF_CGROUP_INET4_GETPEERNAME:
7252 case BPF_CGROUP_INET6_GETPEERNAME:
7253 case BPF_CGROUP_INET4_GETSOCKNAME:
7254 case BPF_CGROUP_INET6_GETSOCKNAME:
7255 return &bpf_sock_addr_getsockopt_proto;
7256 default:
7257 return NULL;
7258 }
7259 default:
7260 return bpf_sk_base_func_proto(func_id);
7261 }
7262 }
7263
7264 static const struct bpf_func_proto *
sk_filter_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7265 sk_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7266 {
7267 switch (func_id) {
7268 case BPF_FUNC_skb_load_bytes:
7269 return &bpf_skb_load_bytes_proto;
7270 case BPF_FUNC_skb_load_bytes_relative:
7271 return &bpf_skb_load_bytes_relative_proto;
7272 case BPF_FUNC_get_socket_cookie:
7273 return &bpf_get_socket_cookie_proto;
7274 case BPF_FUNC_get_socket_uid:
7275 return &bpf_get_socket_uid_proto;
7276 case BPF_FUNC_perf_event_output:
7277 return &bpf_skb_event_output_proto;
7278 default:
7279 return bpf_sk_base_func_proto(func_id);
7280 }
7281 }
7282
7283 const struct bpf_func_proto bpf_sk_storage_get_proto __weak;
7284 const struct bpf_func_proto bpf_sk_storage_delete_proto __weak;
7285
7286 static const struct bpf_func_proto *
cg_skb_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7287 cg_skb_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7288 {
7289 switch (func_id) {
7290 case BPF_FUNC_get_local_storage:
7291 return &bpf_get_local_storage_proto;
7292 case BPF_FUNC_sk_fullsock:
7293 return &bpf_sk_fullsock_proto;
7294 case BPF_FUNC_sk_storage_get:
7295 return &bpf_sk_storage_get_proto;
7296 case BPF_FUNC_sk_storage_delete:
7297 return &bpf_sk_storage_delete_proto;
7298 case BPF_FUNC_perf_event_output:
7299 return &bpf_skb_event_output_proto;
7300 #ifdef CONFIG_SOCK_CGROUP_DATA
7301 case BPF_FUNC_skb_cgroup_id:
7302 return &bpf_skb_cgroup_id_proto;
7303 case BPF_FUNC_skb_ancestor_cgroup_id:
7304 return &bpf_skb_ancestor_cgroup_id_proto;
7305 case BPF_FUNC_sk_cgroup_id:
7306 return &bpf_sk_cgroup_id_proto;
7307 case BPF_FUNC_sk_ancestor_cgroup_id:
7308 return &bpf_sk_ancestor_cgroup_id_proto;
7309 #endif
7310 #ifdef CONFIG_INET
7311 case BPF_FUNC_sk_lookup_tcp:
7312 return &bpf_sk_lookup_tcp_proto;
7313 case BPF_FUNC_sk_lookup_udp:
7314 return &bpf_sk_lookup_udp_proto;
7315 case BPF_FUNC_sk_release:
7316 return &bpf_sk_release_proto;
7317 case BPF_FUNC_skc_lookup_tcp:
7318 return &bpf_skc_lookup_tcp_proto;
7319 case BPF_FUNC_tcp_sock:
7320 return &bpf_tcp_sock_proto;
7321 case BPF_FUNC_get_listener_sock:
7322 return &bpf_get_listener_sock_proto;
7323 case BPF_FUNC_skb_ecn_set_ce:
7324 return &bpf_skb_ecn_set_ce_proto;
7325 #endif
7326 default:
7327 return sk_filter_func_proto(func_id, prog);
7328 }
7329 }
7330
7331 static const struct bpf_func_proto *
tc_cls_act_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7332 tc_cls_act_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7333 {
7334 switch (func_id) {
7335 case BPF_FUNC_skb_store_bytes:
7336 return &bpf_skb_store_bytes_proto;
7337 case BPF_FUNC_skb_load_bytes:
7338 return &bpf_skb_load_bytes_proto;
7339 case BPF_FUNC_skb_load_bytes_relative:
7340 return &bpf_skb_load_bytes_relative_proto;
7341 case BPF_FUNC_skb_pull_data:
7342 return &bpf_skb_pull_data_proto;
7343 case BPF_FUNC_csum_diff:
7344 return &bpf_csum_diff_proto;
7345 case BPF_FUNC_csum_update:
7346 return &bpf_csum_update_proto;
7347 case BPF_FUNC_csum_level:
7348 return &bpf_csum_level_proto;
7349 case BPF_FUNC_l3_csum_replace:
7350 return &bpf_l3_csum_replace_proto;
7351 case BPF_FUNC_l4_csum_replace:
7352 return &bpf_l4_csum_replace_proto;
7353 case BPF_FUNC_clone_redirect:
7354 return &bpf_clone_redirect_proto;
7355 case BPF_FUNC_get_cgroup_classid:
7356 return &bpf_get_cgroup_classid_proto;
7357 case BPF_FUNC_skb_vlan_push:
7358 return &bpf_skb_vlan_push_proto;
7359 case BPF_FUNC_skb_vlan_pop:
7360 return &bpf_skb_vlan_pop_proto;
7361 case BPF_FUNC_skb_change_proto:
7362 return &bpf_skb_change_proto_proto;
7363 case BPF_FUNC_skb_change_type:
7364 return &bpf_skb_change_type_proto;
7365 case BPF_FUNC_skb_adjust_room:
7366 return &bpf_skb_adjust_room_proto;
7367 case BPF_FUNC_skb_change_tail:
7368 return &bpf_skb_change_tail_proto;
7369 case BPF_FUNC_skb_change_head:
7370 return &bpf_skb_change_head_proto;
7371 case BPF_FUNC_skb_get_tunnel_key:
7372 return &bpf_skb_get_tunnel_key_proto;
7373 case BPF_FUNC_skb_set_tunnel_key:
7374 return bpf_get_skb_set_tunnel_proto(func_id);
7375 case BPF_FUNC_skb_get_tunnel_opt:
7376 return &bpf_skb_get_tunnel_opt_proto;
7377 case BPF_FUNC_skb_set_tunnel_opt:
7378 return bpf_get_skb_set_tunnel_proto(func_id);
7379 case BPF_FUNC_redirect:
7380 return &bpf_redirect_proto;
7381 case BPF_FUNC_redirect_neigh:
7382 return &bpf_redirect_neigh_proto;
7383 case BPF_FUNC_redirect_peer:
7384 return &bpf_redirect_peer_proto;
7385 case BPF_FUNC_get_route_realm:
7386 return &bpf_get_route_realm_proto;
7387 case BPF_FUNC_get_hash_recalc:
7388 return &bpf_get_hash_recalc_proto;
7389 case BPF_FUNC_set_hash_invalid:
7390 return &bpf_set_hash_invalid_proto;
7391 case BPF_FUNC_set_hash:
7392 return &bpf_set_hash_proto;
7393 case BPF_FUNC_perf_event_output:
7394 return &bpf_skb_event_output_proto;
7395 case BPF_FUNC_get_smp_processor_id:
7396 return &bpf_get_smp_processor_id_proto;
7397 case BPF_FUNC_skb_under_cgroup:
7398 return &bpf_skb_under_cgroup_proto;
7399 case BPF_FUNC_get_socket_cookie:
7400 return &bpf_get_socket_cookie_proto;
7401 case BPF_FUNC_get_socket_uid:
7402 return &bpf_get_socket_uid_proto;
7403 case BPF_FUNC_fib_lookup:
7404 return &bpf_skb_fib_lookup_proto;
7405 case BPF_FUNC_check_mtu:
7406 return &bpf_skb_check_mtu_proto;
7407 case BPF_FUNC_sk_fullsock:
7408 return &bpf_sk_fullsock_proto;
7409 case BPF_FUNC_sk_storage_get:
7410 return &bpf_sk_storage_get_proto;
7411 case BPF_FUNC_sk_storage_delete:
7412 return &bpf_sk_storage_delete_proto;
7413 #ifdef CONFIG_XFRM
7414 case BPF_FUNC_skb_get_xfrm_state:
7415 return &bpf_skb_get_xfrm_state_proto;
7416 #endif
7417 #ifdef CONFIG_CGROUP_NET_CLASSID
7418 case BPF_FUNC_skb_cgroup_classid:
7419 return &bpf_skb_cgroup_classid_proto;
7420 #endif
7421 #ifdef CONFIG_SOCK_CGROUP_DATA
7422 case BPF_FUNC_skb_cgroup_id:
7423 return &bpf_skb_cgroup_id_proto;
7424 case BPF_FUNC_skb_ancestor_cgroup_id:
7425 return &bpf_skb_ancestor_cgroup_id_proto;
7426 #endif
7427 #ifdef CONFIG_INET
7428 case BPF_FUNC_sk_lookup_tcp:
7429 return &bpf_sk_lookup_tcp_proto;
7430 case BPF_FUNC_sk_lookup_udp:
7431 return &bpf_sk_lookup_udp_proto;
7432 case BPF_FUNC_sk_release:
7433 return &bpf_sk_release_proto;
7434 case BPF_FUNC_tcp_sock:
7435 return &bpf_tcp_sock_proto;
7436 case BPF_FUNC_get_listener_sock:
7437 return &bpf_get_listener_sock_proto;
7438 case BPF_FUNC_skc_lookup_tcp:
7439 return &bpf_skc_lookup_tcp_proto;
7440 case BPF_FUNC_tcp_check_syncookie:
7441 return &bpf_tcp_check_syncookie_proto;
7442 case BPF_FUNC_skb_ecn_set_ce:
7443 return &bpf_skb_ecn_set_ce_proto;
7444 case BPF_FUNC_tcp_gen_syncookie:
7445 return &bpf_tcp_gen_syncookie_proto;
7446 case BPF_FUNC_sk_assign:
7447 return &bpf_sk_assign_proto;
7448 #endif
7449 default:
7450 return bpf_sk_base_func_proto(func_id);
7451 }
7452 }
7453
7454 static const struct bpf_func_proto *
xdp_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7455 xdp_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7456 {
7457 switch (func_id) {
7458 case BPF_FUNC_perf_event_output:
7459 return &bpf_xdp_event_output_proto;
7460 case BPF_FUNC_get_smp_processor_id:
7461 return &bpf_get_smp_processor_id_proto;
7462 case BPF_FUNC_csum_diff:
7463 return &bpf_csum_diff_proto;
7464 case BPF_FUNC_xdp_adjust_head:
7465 return &bpf_xdp_adjust_head_proto;
7466 case BPF_FUNC_xdp_adjust_meta:
7467 return &bpf_xdp_adjust_meta_proto;
7468 case BPF_FUNC_redirect:
7469 return &bpf_xdp_redirect_proto;
7470 case BPF_FUNC_redirect_map:
7471 return &bpf_xdp_redirect_map_proto;
7472 case BPF_FUNC_xdp_adjust_tail:
7473 return &bpf_xdp_adjust_tail_proto;
7474 case BPF_FUNC_fib_lookup:
7475 return &bpf_xdp_fib_lookup_proto;
7476 case BPF_FUNC_check_mtu:
7477 return &bpf_xdp_check_mtu_proto;
7478 #ifdef CONFIG_INET
7479 case BPF_FUNC_sk_lookup_udp:
7480 return &bpf_xdp_sk_lookup_udp_proto;
7481 case BPF_FUNC_sk_lookup_tcp:
7482 return &bpf_xdp_sk_lookup_tcp_proto;
7483 case BPF_FUNC_sk_release:
7484 return &bpf_sk_release_proto;
7485 case BPF_FUNC_skc_lookup_tcp:
7486 return &bpf_xdp_skc_lookup_tcp_proto;
7487 case BPF_FUNC_tcp_check_syncookie:
7488 return &bpf_tcp_check_syncookie_proto;
7489 case BPF_FUNC_tcp_gen_syncookie:
7490 return &bpf_tcp_gen_syncookie_proto;
7491 #endif
7492 default:
7493 return bpf_sk_base_func_proto(func_id);
7494 }
7495 }
7496
7497 const struct bpf_func_proto bpf_sock_map_update_proto __weak;
7498 const struct bpf_func_proto bpf_sock_hash_update_proto __weak;
7499
7500 static const struct bpf_func_proto *
sock_ops_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7501 sock_ops_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7502 {
7503 switch (func_id) {
7504 case BPF_FUNC_setsockopt:
7505 return &bpf_sock_ops_setsockopt_proto;
7506 case BPF_FUNC_getsockopt:
7507 return &bpf_sock_ops_getsockopt_proto;
7508 case BPF_FUNC_sock_ops_cb_flags_set:
7509 return &bpf_sock_ops_cb_flags_set_proto;
7510 case BPF_FUNC_sock_map_update:
7511 return &bpf_sock_map_update_proto;
7512 case BPF_FUNC_sock_hash_update:
7513 return &bpf_sock_hash_update_proto;
7514 case BPF_FUNC_get_socket_cookie:
7515 return &bpf_get_socket_cookie_sock_ops_proto;
7516 case BPF_FUNC_get_local_storage:
7517 return &bpf_get_local_storage_proto;
7518 case BPF_FUNC_perf_event_output:
7519 return &bpf_event_output_data_proto;
7520 case BPF_FUNC_sk_storage_get:
7521 return &bpf_sk_storage_get_proto;
7522 case BPF_FUNC_sk_storage_delete:
7523 return &bpf_sk_storage_delete_proto;
7524 case BPF_FUNC_get_netns_cookie:
7525 return &bpf_get_netns_cookie_sock_ops_proto;
7526 #ifdef CONFIG_INET
7527 case BPF_FUNC_load_hdr_opt:
7528 return &bpf_sock_ops_load_hdr_opt_proto;
7529 case BPF_FUNC_store_hdr_opt:
7530 return &bpf_sock_ops_store_hdr_opt_proto;
7531 case BPF_FUNC_reserve_hdr_opt:
7532 return &bpf_sock_ops_reserve_hdr_opt_proto;
7533 case BPF_FUNC_tcp_sock:
7534 return &bpf_tcp_sock_proto;
7535 #endif /* CONFIG_INET */
7536 default:
7537 return bpf_sk_base_func_proto(func_id);
7538 }
7539 }
7540
7541 const struct bpf_func_proto bpf_msg_redirect_map_proto __weak;
7542 const struct bpf_func_proto bpf_msg_redirect_hash_proto __weak;
7543
7544 static const struct bpf_func_proto *
sk_msg_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7545 sk_msg_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7546 {
7547 switch (func_id) {
7548 case BPF_FUNC_msg_redirect_map:
7549 return &bpf_msg_redirect_map_proto;
7550 case BPF_FUNC_msg_redirect_hash:
7551 return &bpf_msg_redirect_hash_proto;
7552 case BPF_FUNC_msg_apply_bytes:
7553 return &bpf_msg_apply_bytes_proto;
7554 case BPF_FUNC_msg_cork_bytes:
7555 return &bpf_msg_cork_bytes_proto;
7556 case BPF_FUNC_msg_pull_data:
7557 return &bpf_msg_pull_data_proto;
7558 case BPF_FUNC_msg_push_data:
7559 return &bpf_msg_push_data_proto;
7560 case BPF_FUNC_msg_pop_data:
7561 return &bpf_msg_pop_data_proto;
7562 case BPF_FUNC_perf_event_output:
7563 return &bpf_event_output_data_proto;
7564 case BPF_FUNC_get_current_uid_gid:
7565 return &bpf_get_current_uid_gid_proto;
7566 case BPF_FUNC_get_current_pid_tgid:
7567 return &bpf_get_current_pid_tgid_proto;
7568 case BPF_FUNC_sk_storage_get:
7569 return &bpf_sk_storage_get_proto;
7570 case BPF_FUNC_sk_storage_delete:
7571 return &bpf_sk_storage_delete_proto;
7572 case BPF_FUNC_get_netns_cookie:
7573 return &bpf_get_netns_cookie_sk_msg_proto;
7574 #ifdef CONFIG_CGROUPS
7575 case BPF_FUNC_get_current_cgroup_id:
7576 return &bpf_get_current_cgroup_id_proto;
7577 case BPF_FUNC_get_current_ancestor_cgroup_id:
7578 return &bpf_get_current_ancestor_cgroup_id_proto;
7579 #endif
7580 #ifdef CONFIG_CGROUP_NET_CLASSID
7581 case BPF_FUNC_get_cgroup_classid:
7582 return &bpf_get_cgroup_classid_curr_proto;
7583 #endif
7584 default:
7585 return bpf_sk_base_func_proto(func_id);
7586 }
7587 }
7588
7589 const struct bpf_func_proto bpf_sk_redirect_map_proto __weak;
7590 const struct bpf_func_proto bpf_sk_redirect_hash_proto __weak;
7591
7592 static const struct bpf_func_proto *
sk_skb_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7593 sk_skb_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7594 {
7595 switch (func_id) {
7596 case BPF_FUNC_skb_store_bytes:
7597 return &bpf_skb_store_bytes_proto;
7598 case BPF_FUNC_skb_load_bytes:
7599 return &bpf_skb_load_bytes_proto;
7600 case BPF_FUNC_skb_pull_data:
7601 return &sk_skb_pull_data_proto;
7602 case BPF_FUNC_skb_change_tail:
7603 return &sk_skb_change_tail_proto;
7604 case BPF_FUNC_skb_change_head:
7605 return &sk_skb_change_head_proto;
7606 case BPF_FUNC_skb_adjust_room:
7607 return &sk_skb_adjust_room_proto;
7608 case BPF_FUNC_get_socket_cookie:
7609 return &bpf_get_socket_cookie_proto;
7610 case BPF_FUNC_get_socket_uid:
7611 return &bpf_get_socket_uid_proto;
7612 case BPF_FUNC_sk_redirect_map:
7613 return &bpf_sk_redirect_map_proto;
7614 case BPF_FUNC_sk_redirect_hash:
7615 return &bpf_sk_redirect_hash_proto;
7616 case BPF_FUNC_perf_event_output:
7617 return &bpf_skb_event_output_proto;
7618 #ifdef CONFIG_INET
7619 case BPF_FUNC_sk_lookup_tcp:
7620 return &bpf_sk_lookup_tcp_proto;
7621 case BPF_FUNC_sk_lookup_udp:
7622 return &bpf_sk_lookup_udp_proto;
7623 case BPF_FUNC_sk_release:
7624 return &bpf_sk_release_proto;
7625 case BPF_FUNC_skc_lookup_tcp:
7626 return &bpf_skc_lookup_tcp_proto;
7627 #endif
7628 default:
7629 return bpf_sk_base_func_proto(func_id);
7630 }
7631 }
7632
7633 static const struct bpf_func_proto *
flow_dissector_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7634 flow_dissector_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7635 {
7636 switch (func_id) {
7637 case BPF_FUNC_skb_load_bytes:
7638 return &bpf_flow_dissector_load_bytes_proto;
7639 default:
7640 return bpf_sk_base_func_proto(func_id);
7641 }
7642 }
7643
7644 static const struct bpf_func_proto *
lwt_out_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7645 lwt_out_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7646 {
7647 switch (func_id) {
7648 case BPF_FUNC_skb_load_bytes:
7649 return &bpf_skb_load_bytes_proto;
7650 case BPF_FUNC_skb_pull_data:
7651 return &bpf_skb_pull_data_proto;
7652 case BPF_FUNC_csum_diff:
7653 return &bpf_csum_diff_proto;
7654 case BPF_FUNC_get_cgroup_classid:
7655 return &bpf_get_cgroup_classid_proto;
7656 case BPF_FUNC_get_route_realm:
7657 return &bpf_get_route_realm_proto;
7658 case BPF_FUNC_get_hash_recalc:
7659 return &bpf_get_hash_recalc_proto;
7660 case BPF_FUNC_perf_event_output:
7661 return &bpf_skb_event_output_proto;
7662 case BPF_FUNC_get_smp_processor_id:
7663 return &bpf_get_smp_processor_id_proto;
7664 case BPF_FUNC_skb_under_cgroup:
7665 return &bpf_skb_under_cgroup_proto;
7666 default:
7667 return bpf_sk_base_func_proto(func_id);
7668 }
7669 }
7670
7671 static const struct bpf_func_proto *
lwt_in_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7672 lwt_in_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7673 {
7674 switch (func_id) {
7675 case BPF_FUNC_lwt_push_encap:
7676 return &bpf_lwt_in_push_encap_proto;
7677 default:
7678 return lwt_out_func_proto(func_id, prog);
7679 }
7680 }
7681
7682 static const struct bpf_func_proto *
lwt_xmit_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7683 lwt_xmit_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7684 {
7685 switch (func_id) {
7686 case BPF_FUNC_skb_get_tunnel_key:
7687 return &bpf_skb_get_tunnel_key_proto;
7688 case BPF_FUNC_skb_set_tunnel_key:
7689 return bpf_get_skb_set_tunnel_proto(func_id);
7690 case BPF_FUNC_skb_get_tunnel_opt:
7691 return &bpf_skb_get_tunnel_opt_proto;
7692 case BPF_FUNC_skb_set_tunnel_opt:
7693 return bpf_get_skb_set_tunnel_proto(func_id);
7694 case BPF_FUNC_redirect:
7695 return &bpf_redirect_proto;
7696 case BPF_FUNC_clone_redirect:
7697 return &bpf_clone_redirect_proto;
7698 case BPF_FUNC_skb_change_tail:
7699 return &bpf_skb_change_tail_proto;
7700 case BPF_FUNC_skb_change_head:
7701 return &bpf_skb_change_head_proto;
7702 case BPF_FUNC_skb_store_bytes:
7703 return &bpf_skb_store_bytes_proto;
7704 case BPF_FUNC_csum_update:
7705 return &bpf_csum_update_proto;
7706 case BPF_FUNC_csum_level:
7707 return &bpf_csum_level_proto;
7708 case BPF_FUNC_l3_csum_replace:
7709 return &bpf_l3_csum_replace_proto;
7710 case BPF_FUNC_l4_csum_replace:
7711 return &bpf_l4_csum_replace_proto;
7712 case BPF_FUNC_set_hash_invalid:
7713 return &bpf_set_hash_invalid_proto;
7714 case BPF_FUNC_lwt_push_encap:
7715 return &bpf_lwt_xmit_push_encap_proto;
7716 default:
7717 return lwt_out_func_proto(func_id, prog);
7718 }
7719 }
7720
7721 static const struct bpf_func_proto *
lwt_seg6local_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7722 lwt_seg6local_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7723 {
7724 switch (func_id) {
7725 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
7726 case BPF_FUNC_lwt_seg6_store_bytes:
7727 return &bpf_lwt_seg6_store_bytes_proto;
7728 case BPF_FUNC_lwt_seg6_action:
7729 return &bpf_lwt_seg6_action_proto;
7730 case BPF_FUNC_lwt_seg6_adjust_srh:
7731 return &bpf_lwt_seg6_adjust_srh_proto;
7732 #endif
7733 default:
7734 return lwt_out_func_proto(func_id, prog);
7735 }
7736 }
7737
bpf_skb_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)7738 static bool bpf_skb_is_valid_access(int off, int size, enum bpf_access_type type,
7739 const struct bpf_prog *prog,
7740 struct bpf_insn_access_aux *info)
7741 {
7742 const int size_default = sizeof(__u32);
7743
7744 if (off < 0 || off >= sizeof(struct __sk_buff))
7745 return false;
7746
7747 /* The verifier guarantees that size > 0. */
7748 if (off % size != 0)
7749 return false;
7750
7751 switch (off) {
7752 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
7753 if (off + size > offsetofend(struct __sk_buff, cb[4]))
7754 return false;
7755 break;
7756 case bpf_ctx_range_till(struct __sk_buff, remote_ip6[0], remote_ip6[3]):
7757 case bpf_ctx_range_till(struct __sk_buff, local_ip6[0], local_ip6[3]):
7758 case bpf_ctx_range_till(struct __sk_buff, remote_ip4, remote_ip4):
7759 case bpf_ctx_range_till(struct __sk_buff, local_ip4, local_ip4):
7760 case bpf_ctx_range(struct __sk_buff, data):
7761 case bpf_ctx_range(struct __sk_buff, data_meta):
7762 case bpf_ctx_range(struct __sk_buff, data_end):
7763 if (size != size_default)
7764 return false;
7765 break;
7766 case bpf_ctx_range_ptr(struct __sk_buff, flow_keys):
7767 return false;
7768 case bpf_ctx_range(struct __sk_buff, tstamp):
7769 if (size != sizeof(__u64))
7770 return false;
7771 break;
7772 case offsetof(struct __sk_buff, sk):
7773 if (type == BPF_WRITE || size != sizeof(__u64))
7774 return false;
7775 info->reg_type = PTR_TO_SOCK_COMMON_OR_NULL;
7776 break;
7777 default:
7778 /* Only narrow read access allowed for now. */
7779 if (type == BPF_WRITE) {
7780 if (size != size_default)
7781 return false;
7782 } else {
7783 bpf_ctx_record_field_size(info, size_default);
7784 if (!bpf_ctx_narrow_access_ok(off, size, size_default))
7785 return false;
7786 }
7787 }
7788
7789 return true;
7790 }
7791
sk_filter_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)7792 static bool sk_filter_is_valid_access(int off, int size,
7793 enum bpf_access_type type,
7794 const struct bpf_prog *prog,
7795 struct bpf_insn_access_aux *info)
7796 {
7797 switch (off) {
7798 case bpf_ctx_range(struct __sk_buff, tc_classid):
7799 case bpf_ctx_range(struct __sk_buff, data):
7800 case bpf_ctx_range(struct __sk_buff, data_meta):
7801 case bpf_ctx_range(struct __sk_buff, data_end):
7802 case bpf_ctx_range_till(struct __sk_buff, family, local_port):
7803 case bpf_ctx_range(struct __sk_buff, tstamp):
7804 case bpf_ctx_range(struct __sk_buff, wire_len):
7805 return false;
7806 }
7807
7808 if (type == BPF_WRITE) {
7809 switch (off) {
7810 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
7811 break;
7812 default:
7813 return false;
7814 }
7815 }
7816
7817 return bpf_skb_is_valid_access(off, size, type, prog, info);
7818 }
7819
cg_skb_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)7820 static bool cg_skb_is_valid_access(int off, int size,
7821 enum bpf_access_type type,
7822 const struct bpf_prog *prog,
7823 struct bpf_insn_access_aux *info)
7824 {
7825 switch (off) {
7826 case bpf_ctx_range(struct __sk_buff, tc_classid):
7827 case bpf_ctx_range(struct __sk_buff, data_meta):
7828 case bpf_ctx_range(struct __sk_buff, wire_len):
7829 return false;
7830 case bpf_ctx_range(struct __sk_buff, data):
7831 case bpf_ctx_range(struct __sk_buff, data_end):
7832 if (!bpf_capable())
7833 return false;
7834 break;
7835 }
7836
7837 if (type == BPF_WRITE) {
7838 switch (off) {
7839 case bpf_ctx_range(struct __sk_buff, mark):
7840 case bpf_ctx_range(struct __sk_buff, priority):
7841 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
7842 break;
7843 case bpf_ctx_range(struct __sk_buff, tstamp):
7844 if (!bpf_capable())
7845 return false;
7846 break;
7847 default:
7848 return false;
7849 }
7850 }
7851
7852 switch (off) {
7853 case bpf_ctx_range(struct __sk_buff, data):
7854 info->reg_type = PTR_TO_PACKET;
7855 break;
7856 case bpf_ctx_range(struct __sk_buff, data_end):
7857 info->reg_type = PTR_TO_PACKET_END;
7858 break;
7859 }
7860
7861 return bpf_skb_is_valid_access(off, size, type, prog, info);
7862 }
7863
lwt_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)7864 static bool lwt_is_valid_access(int off, int size,
7865 enum bpf_access_type type,
7866 const struct bpf_prog *prog,
7867 struct bpf_insn_access_aux *info)
7868 {
7869 switch (off) {
7870 case bpf_ctx_range(struct __sk_buff, tc_classid):
7871 case bpf_ctx_range_till(struct __sk_buff, family, local_port):
7872 case bpf_ctx_range(struct __sk_buff, data_meta):
7873 case bpf_ctx_range(struct __sk_buff, tstamp):
7874 case bpf_ctx_range(struct __sk_buff, wire_len):
7875 return false;
7876 }
7877
7878 if (type == BPF_WRITE) {
7879 switch (off) {
7880 case bpf_ctx_range(struct __sk_buff, mark):
7881 case bpf_ctx_range(struct __sk_buff, priority):
7882 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
7883 break;
7884 default:
7885 return false;
7886 }
7887 }
7888
7889 switch (off) {
7890 case bpf_ctx_range(struct __sk_buff, data):
7891 info->reg_type = PTR_TO_PACKET;
7892 break;
7893 case bpf_ctx_range(struct __sk_buff, data_end):
7894 info->reg_type = PTR_TO_PACKET_END;
7895 break;
7896 }
7897
7898 return bpf_skb_is_valid_access(off, size, type, prog, info);
7899 }
7900
7901 /* Attach type specific accesses */
__sock_filter_check_attach_type(int off,enum bpf_access_type access_type,enum bpf_attach_type attach_type)7902 static bool __sock_filter_check_attach_type(int off,
7903 enum bpf_access_type access_type,
7904 enum bpf_attach_type attach_type)
7905 {
7906 switch (off) {
7907 case offsetof(struct bpf_sock, bound_dev_if):
7908 case offsetof(struct bpf_sock, mark):
7909 case offsetof(struct bpf_sock, priority):
7910 switch (attach_type) {
7911 case BPF_CGROUP_INET_SOCK_CREATE:
7912 case BPF_CGROUP_INET_SOCK_RELEASE:
7913 goto full_access;
7914 default:
7915 return false;
7916 }
7917 case bpf_ctx_range(struct bpf_sock, src_ip4):
7918 switch (attach_type) {
7919 case BPF_CGROUP_INET4_POST_BIND:
7920 goto read_only;
7921 default:
7922 return false;
7923 }
7924 case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]):
7925 switch (attach_type) {
7926 case BPF_CGROUP_INET6_POST_BIND:
7927 goto read_only;
7928 default:
7929 return false;
7930 }
7931 case bpf_ctx_range(struct bpf_sock, src_port):
7932 switch (attach_type) {
7933 case BPF_CGROUP_INET4_POST_BIND:
7934 case BPF_CGROUP_INET6_POST_BIND:
7935 goto read_only;
7936 default:
7937 return false;
7938 }
7939 }
7940 read_only:
7941 return access_type == BPF_READ;
7942 full_access:
7943 return true;
7944 }
7945
bpf_sock_common_is_valid_access(int off,int size,enum bpf_access_type type,struct bpf_insn_access_aux * info)7946 bool bpf_sock_common_is_valid_access(int off, int size,
7947 enum bpf_access_type type,
7948 struct bpf_insn_access_aux *info)
7949 {
7950 switch (off) {
7951 case bpf_ctx_range_till(struct bpf_sock, type, priority):
7952 return false;
7953 default:
7954 return bpf_sock_is_valid_access(off, size, type, info);
7955 }
7956 }
7957
bpf_sock_is_valid_access(int off,int size,enum bpf_access_type type,struct bpf_insn_access_aux * info)7958 bool bpf_sock_is_valid_access(int off, int size, enum bpf_access_type type,
7959 struct bpf_insn_access_aux *info)
7960 {
7961 const int size_default = sizeof(__u32);
7962
7963 if (off < 0 || off >= sizeof(struct bpf_sock))
7964 return false;
7965 if (off % size != 0)
7966 return false;
7967
7968 switch (off) {
7969 case offsetof(struct bpf_sock, state):
7970 case offsetof(struct bpf_sock, family):
7971 case offsetof(struct bpf_sock, type):
7972 case offsetof(struct bpf_sock, protocol):
7973 case offsetof(struct bpf_sock, dst_port):
7974 case offsetof(struct bpf_sock, src_port):
7975 case offsetof(struct bpf_sock, rx_queue_mapping):
7976 case bpf_ctx_range(struct bpf_sock, src_ip4):
7977 case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]):
7978 case bpf_ctx_range(struct bpf_sock, dst_ip4):
7979 case bpf_ctx_range_till(struct bpf_sock, dst_ip6[0], dst_ip6[3]):
7980 bpf_ctx_record_field_size(info, size_default);
7981 return bpf_ctx_narrow_access_ok(off, size, size_default);
7982 }
7983
7984 return size == size_default;
7985 }
7986
sock_filter_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)7987 static bool sock_filter_is_valid_access(int off, int size,
7988 enum bpf_access_type type,
7989 const struct bpf_prog *prog,
7990 struct bpf_insn_access_aux *info)
7991 {
7992 if (!bpf_sock_is_valid_access(off, size, type, info))
7993 return false;
7994 return __sock_filter_check_attach_type(off, type,
7995 prog->expected_attach_type);
7996 }
7997
bpf_noop_prologue(struct bpf_insn * insn_buf,bool direct_write,const struct bpf_prog * prog)7998 static int bpf_noop_prologue(struct bpf_insn *insn_buf, bool direct_write,
7999 const struct bpf_prog *prog)
8000 {
8001 /* Neither direct read nor direct write requires any preliminary
8002 * action.
8003 */
8004 return 0;
8005 }
8006
bpf_unclone_prologue(struct bpf_insn * insn_buf,bool direct_write,const struct bpf_prog * prog,int drop_verdict)8007 static int bpf_unclone_prologue(struct bpf_insn *insn_buf, bool direct_write,
8008 const struct bpf_prog *prog, int drop_verdict)
8009 {
8010 struct bpf_insn *insn = insn_buf;
8011
8012 if (!direct_write)
8013 return 0;
8014
8015 /* if (!skb->cloned)
8016 * goto start;
8017 *
8018 * (Fast-path, otherwise approximation that we might be
8019 * a clone, do the rest in helper.)
8020 */
8021 *insn++ = BPF_LDX_MEM(BPF_B, BPF_REG_6, BPF_REG_1, CLONED_OFFSET());
8022 *insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_6, CLONED_MASK);
8023 *insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_6, 0, 7);
8024
8025 /* ret = bpf_skb_pull_data(skb, 0); */
8026 *insn++ = BPF_MOV64_REG(BPF_REG_6, BPF_REG_1);
8027 *insn++ = BPF_ALU64_REG(BPF_XOR, BPF_REG_2, BPF_REG_2);
8028 *insn++ = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
8029 BPF_FUNC_skb_pull_data);
8030 /* if (!ret)
8031 * goto restore;
8032 * return TC_ACT_SHOT;
8033 */
8034 *insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2);
8035 *insn++ = BPF_ALU32_IMM(BPF_MOV, BPF_REG_0, drop_verdict);
8036 *insn++ = BPF_EXIT_INSN();
8037
8038 /* restore: */
8039 *insn++ = BPF_MOV64_REG(BPF_REG_1, BPF_REG_6);
8040 /* start: */
8041 *insn++ = prog->insnsi[0];
8042
8043 return insn - insn_buf;
8044 }
8045
bpf_gen_ld_abs(const struct bpf_insn * orig,struct bpf_insn * insn_buf)8046 static int bpf_gen_ld_abs(const struct bpf_insn *orig,
8047 struct bpf_insn *insn_buf)
8048 {
8049 bool indirect = BPF_MODE(orig->code) == BPF_IND;
8050 struct bpf_insn *insn = insn_buf;
8051
8052 if (!indirect) {
8053 *insn++ = BPF_MOV64_IMM(BPF_REG_2, orig->imm);
8054 } else {
8055 *insn++ = BPF_MOV64_REG(BPF_REG_2, orig->src_reg);
8056 if (orig->imm)
8057 *insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, orig->imm);
8058 }
8059 /* We're guaranteed here that CTX is in R6. */
8060 *insn++ = BPF_MOV64_REG(BPF_REG_1, BPF_REG_CTX);
8061
8062 switch (BPF_SIZE(orig->code)) {
8063 case BPF_B:
8064 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_8_no_cache);
8065 break;
8066 case BPF_H:
8067 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_16_no_cache);
8068 break;
8069 case BPF_W:
8070 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_32_no_cache);
8071 break;
8072 }
8073
8074 *insn++ = BPF_JMP_IMM(BPF_JSGE, BPF_REG_0, 0, 2);
8075 *insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_0, BPF_REG_0);
8076 *insn++ = BPF_EXIT_INSN();
8077
8078 return insn - insn_buf;
8079 }
8080
tc_cls_act_prologue(struct bpf_insn * insn_buf,bool direct_write,const struct bpf_prog * prog)8081 static int tc_cls_act_prologue(struct bpf_insn *insn_buf, bool direct_write,
8082 const struct bpf_prog *prog)
8083 {
8084 return bpf_unclone_prologue(insn_buf, direct_write, prog, TC_ACT_SHOT);
8085 }
8086
tc_cls_act_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)8087 static bool tc_cls_act_is_valid_access(int off, int size,
8088 enum bpf_access_type type,
8089 const struct bpf_prog *prog,
8090 struct bpf_insn_access_aux *info)
8091 {
8092 if (type == BPF_WRITE) {
8093 switch (off) {
8094 case bpf_ctx_range(struct __sk_buff, mark):
8095 case bpf_ctx_range(struct __sk_buff, tc_index):
8096 case bpf_ctx_range(struct __sk_buff, priority):
8097 case bpf_ctx_range(struct __sk_buff, tc_classid):
8098 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
8099 case bpf_ctx_range(struct __sk_buff, tstamp):
8100 case bpf_ctx_range(struct __sk_buff, queue_mapping):
8101 break;
8102 default:
8103 return false;
8104 }
8105 }
8106
8107 switch (off) {
8108 case bpf_ctx_range(struct __sk_buff, data):
8109 info->reg_type = PTR_TO_PACKET;
8110 break;
8111 case bpf_ctx_range(struct __sk_buff, data_meta):
8112 info->reg_type = PTR_TO_PACKET_META;
8113 break;
8114 case bpf_ctx_range(struct __sk_buff, data_end):
8115 info->reg_type = PTR_TO_PACKET_END;
8116 break;
8117 case bpf_ctx_range_till(struct __sk_buff, family, local_port):
8118 return false;
8119 }
8120
8121 return bpf_skb_is_valid_access(off, size, type, prog, info);
8122 }
8123
__is_valid_xdp_access(int off,int size)8124 static bool __is_valid_xdp_access(int off, int size)
8125 {
8126 if (off < 0 || off >= sizeof(struct xdp_md))
8127 return false;
8128 if (off % size != 0)
8129 return false;
8130 if (size != sizeof(__u32))
8131 return false;
8132
8133 return true;
8134 }
8135
xdp_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)8136 static bool xdp_is_valid_access(int off, int size,
8137 enum bpf_access_type type,
8138 const struct bpf_prog *prog,
8139 struct bpf_insn_access_aux *info)
8140 {
8141 if (prog->expected_attach_type != BPF_XDP_DEVMAP) {
8142 switch (off) {
8143 case offsetof(struct xdp_md, egress_ifindex):
8144 return false;
8145 }
8146 }
8147
8148 if (type == BPF_WRITE) {
8149 if (bpf_prog_is_dev_bound(prog->aux)) {
8150 switch (off) {
8151 case offsetof(struct xdp_md, rx_queue_index):
8152 return __is_valid_xdp_access(off, size);
8153 }
8154 }
8155 return false;
8156 }
8157
8158 switch (off) {
8159 case offsetof(struct xdp_md, data):
8160 info->reg_type = PTR_TO_PACKET;
8161 break;
8162 case offsetof(struct xdp_md, data_meta):
8163 info->reg_type = PTR_TO_PACKET_META;
8164 break;
8165 case offsetof(struct xdp_md, data_end):
8166 info->reg_type = PTR_TO_PACKET_END;
8167 break;
8168 }
8169
8170 return __is_valid_xdp_access(off, size);
8171 }
8172
bpf_warn_invalid_xdp_action(u32 act)8173 void bpf_warn_invalid_xdp_action(u32 act)
8174 {
8175 const u32 act_max = XDP_REDIRECT;
8176
8177 WARN_ONCE(1, "%s XDP return value %u, expect packet loss!\n",
8178 act > act_max ? "Illegal" : "Driver unsupported",
8179 act);
8180 }
8181 EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_action);
8182
sock_addr_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)8183 static bool sock_addr_is_valid_access(int off, int size,
8184 enum bpf_access_type type,
8185 const struct bpf_prog *prog,
8186 struct bpf_insn_access_aux *info)
8187 {
8188 const int size_default = sizeof(__u32);
8189
8190 if (off < 0 || off >= sizeof(struct bpf_sock_addr))
8191 return false;
8192 if (off % size != 0)
8193 return false;
8194
8195 /* Disallow access to IPv6 fields from IPv4 contex and vise
8196 * versa.
8197 */
8198 switch (off) {
8199 case bpf_ctx_range(struct bpf_sock_addr, user_ip4):
8200 switch (prog->expected_attach_type) {
8201 case BPF_CGROUP_INET4_BIND:
8202 case BPF_CGROUP_INET4_CONNECT:
8203 case BPF_CGROUP_INET4_GETPEERNAME:
8204 case BPF_CGROUP_INET4_GETSOCKNAME:
8205 case BPF_CGROUP_UDP4_SENDMSG:
8206 case BPF_CGROUP_UDP4_RECVMSG:
8207 break;
8208 default:
8209 return false;
8210 }
8211 break;
8212 case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]):
8213 switch (prog->expected_attach_type) {
8214 case BPF_CGROUP_INET6_BIND:
8215 case BPF_CGROUP_INET6_CONNECT:
8216 case BPF_CGROUP_INET6_GETPEERNAME:
8217 case BPF_CGROUP_INET6_GETSOCKNAME:
8218 case BPF_CGROUP_UDP6_SENDMSG:
8219 case BPF_CGROUP_UDP6_RECVMSG:
8220 break;
8221 default:
8222 return false;
8223 }
8224 break;
8225 case bpf_ctx_range(struct bpf_sock_addr, msg_src_ip4):
8226 switch (prog->expected_attach_type) {
8227 case BPF_CGROUP_UDP4_SENDMSG:
8228 break;
8229 default:
8230 return false;
8231 }
8232 break;
8233 case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0],
8234 msg_src_ip6[3]):
8235 switch (prog->expected_attach_type) {
8236 case BPF_CGROUP_UDP6_SENDMSG:
8237 break;
8238 default:
8239 return false;
8240 }
8241 break;
8242 }
8243
8244 switch (off) {
8245 case bpf_ctx_range(struct bpf_sock_addr, user_ip4):
8246 case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]):
8247 case bpf_ctx_range(struct bpf_sock_addr, msg_src_ip4):
8248 case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0],
8249 msg_src_ip6[3]):
8250 case bpf_ctx_range(struct bpf_sock_addr, user_port):
8251 if (type == BPF_READ) {
8252 bpf_ctx_record_field_size(info, size_default);
8253
8254 if (bpf_ctx_wide_access_ok(off, size,
8255 struct bpf_sock_addr,
8256 user_ip6))
8257 return true;
8258
8259 if (bpf_ctx_wide_access_ok(off, size,
8260 struct bpf_sock_addr,
8261 msg_src_ip6))
8262 return true;
8263
8264 if (!bpf_ctx_narrow_access_ok(off, size, size_default))
8265 return false;
8266 } else {
8267 if (bpf_ctx_wide_access_ok(off, size,
8268 struct bpf_sock_addr,
8269 user_ip6))
8270 return true;
8271
8272 if (bpf_ctx_wide_access_ok(off, size,
8273 struct bpf_sock_addr,
8274 msg_src_ip6))
8275 return true;
8276
8277 if (size != size_default)
8278 return false;
8279 }
8280 break;
8281 case offsetof(struct bpf_sock_addr, sk):
8282 if (type != BPF_READ)
8283 return false;
8284 if (size != sizeof(__u64))
8285 return false;
8286 info->reg_type = PTR_TO_SOCKET;
8287 break;
8288 default:
8289 if (type == BPF_READ) {
8290 if (size != size_default)
8291 return false;
8292 } else {
8293 return false;
8294 }
8295 }
8296
8297 return true;
8298 }
8299
sock_ops_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)8300 static bool sock_ops_is_valid_access(int off, int size,
8301 enum bpf_access_type type,
8302 const struct bpf_prog *prog,
8303 struct bpf_insn_access_aux *info)
8304 {
8305 const int size_default = sizeof(__u32);
8306
8307 if (off < 0 || off >= sizeof(struct bpf_sock_ops))
8308 return false;
8309
8310 /* The verifier guarantees that size > 0. */
8311 if (off % size != 0)
8312 return false;
8313
8314 if (type == BPF_WRITE) {
8315 switch (off) {
8316 case offsetof(struct bpf_sock_ops, reply):
8317 case offsetof(struct bpf_sock_ops, sk_txhash):
8318 if (size != size_default)
8319 return false;
8320 break;
8321 default:
8322 return false;
8323 }
8324 } else {
8325 switch (off) {
8326 case bpf_ctx_range_till(struct bpf_sock_ops, bytes_received,
8327 bytes_acked):
8328 if (size != sizeof(__u64))
8329 return false;
8330 break;
8331 case offsetof(struct bpf_sock_ops, sk):
8332 if (size != sizeof(__u64))
8333 return false;
8334 info->reg_type = PTR_TO_SOCKET_OR_NULL;
8335 break;
8336 case offsetof(struct bpf_sock_ops, skb_data):
8337 if (size != sizeof(__u64))
8338 return false;
8339 info->reg_type = PTR_TO_PACKET;
8340 break;
8341 case offsetof(struct bpf_sock_ops, skb_data_end):
8342 if (size != sizeof(__u64))
8343 return false;
8344 info->reg_type = PTR_TO_PACKET_END;
8345 break;
8346 case offsetof(struct bpf_sock_ops, skb_tcp_flags):
8347 bpf_ctx_record_field_size(info, size_default);
8348 return bpf_ctx_narrow_access_ok(off, size,
8349 size_default);
8350 default:
8351 if (size != size_default)
8352 return false;
8353 break;
8354 }
8355 }
8356
8357 return true;
8358 }
8359
sk_skb_prologue(struct bpf_insn * insn_buf,bool direct_write,const struct bpf_prog * prog)8360 static int sk_skb_prologue(struct bpf_insn *insn_buf, bool direct_write,
8361 const struct bpf_prog *prog)
8362 {
8363 return bpf_unclone_prologue(insn_buf, direct_write, prog, SK_DROP);
8364 }
8365
sk_skb_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)8366 static bool sk_skb_is_valid_access(int off, int size,
8367 enum bpf_access_type type,
8368 const struct bpf_prog *prog,
8369 struct bpf_insn_access_aux *info)
8370 {
8371 switch (off) {
8372 case bpf_ctx_range(struct __sk_buff, tc_classid):
8373 case bpf_ctx_range(struct __sk_buff, data_meta):
8374 case bpf_ctx_range(struct __sk_buff, tstamp):
8375 case bpf_ctx_range(struct __sk_buff, wire_len):
8376 return false;
8377 }
8378
8379 if (type == BPF_WRITE) {
8380 switch (off) {
8381 case bpf_ctx_range(struct __sk_buff, tc_index):
8382 case bpf_ctx_range(struct __sk_buff, priority):
8383 break;
8384 default:
8385 return false;
8386 }
8387 }
8388
8389 switch (off) {
8390 case bpf_ctx_range(struct __sk_buff, mark):
8391 return false;
8392 case bpf_ctx_range(struct __sk_buff, data):
8393 info->reg_type = PTR_TO_PACKET;
8394 break;
8395 case bpf_ctx_range(struct __sk_buff, data_end):
8396 info->reg_type = PTR_TO_PACKET_END;
8397 break;
8398 }
8399
8400 return bpf_skb_is_valid_access(off, size, type, prog, info);
8401 }
8402
sk_msg_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)8403 static bool sk_msg_is_valid_access(int off, int size,
8404 enum bpf_access_type type,
8405 const struct bpf_prog *prog,
8406 struct bpf_insn_access_aux *info)
8407 {
8408 if (type == BPF_WRITE)
8409 return false;
8410
8411 if (off % size != 0)
8412 return false;
8413
8414 switch (off) {
8415 case offsetof(struct sk_msg_md, data):
8416 info->reg_type = PTR_TO_PACKET;
8417 if (size != sizeof(__u64))
8418 return false;
8419 break;
8420 case offsetof(struct sk_msg_md, data_end):
8421 info->reg_type = PTR_TO_PACKET_END;
8422 if (size != sizeof(__u64))
8423 return false;
8424 break;
8425 case offsetof(struct sk_msg_md, sk):
8426 if (size != sizeof(__u64))
8427 return false;
8428 info->reg_type = PTR_TO_SOCKET;
8429 break;
8430 case bpf_ctx_range(struct sk_msg_md, family):
8431 case bpf_ctx_range(struct sk_msg_md, remote_ip4):
8432 case bpf_ctx_range(struct sk_msg_md, local_ip4):
8433 case bpf_ctx_range_till(struct sk_msg_md, remote_ip6[0], remote_ip6[3]):
8434 case bpf_ctx_range_till(struct sk_msg_md, local_ip6[0], local_ip6[3]):
8435 case bpf_ctx_range(struct sk_msg_md, remote_port):
8436 case bpf_ctx_range(struct sk_msg_md, local_port):
8437 case bpf_ctx_range(struct sk_msg_md, size):
8438 if (size != sizeof(__u32))
8439 return false;
8440 break;
8441 default:
8442 return false;
8443 }
8444 return true;
8445 }
8446
flow_dissector_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)8447 static bool flow_dissector_is_valid_access(int off, int size,
8448 enum bpf_access_type type,
8449 const struct bpf_prog *prog,
8450 struct bpf_insn_access_aux *info)
8451 {
8452 const int size_default = sizeof(__u32);
8453
8454 if (off < 0 || off >= sizeof(struct __sk_buff))
8455 return false;
8456
8457 if (type == BPF_WRITE)
8458 return false;
8459
8460 switch (off) {
8461 case bpf_ctx_range(struct __sk_buff, data):
8462 if (size != size_default)
8463 return false;
8464 info->reg_type = PTR_TO_PACKET;
8465 return true;
8466 case bpf_ctx_range(struct __sk_buff, data_end):
8467 if (size != size_default)
8468 return false;
8469 info->reg_type = PTR_TO_PACKET_END;
8470 return true;
8471 case bpf_ctx_range_ptr(struct __sk_buff, flow_keys):
8472 if (size != sizeof(__u64))
8473 return false;
8474 info->reg_type = PTR_TO_FLOW_KEYS;
8475 return true;
8476 default:
8477 return false;
8478 }
8479 }
8480
flow_dissector_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)8481 static u32 flow_dissector_convert_ctx_access(enum bpf_access_type type,
8482 const struct bpf_insn *si,
8483 struct bpf_insn *insn_buf,
8484 struct bpf_prog *prog,
8485 u32 *target_size)
8486
8487 {
8488 struct bpf_insn *insn = insn_buf;
8489
8490 switch (si->off) {
8491 case offsetof(struct __sk_buff, data):
8492 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_flow_dissector, data),
8493 si->dst_reg, si->src_reg,
8494 offsetof(struct bpf_flow_dissector, data));
8495 break;
8496
8497 case offsetof(struct __sk_buff, data_end):
8498 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_flow_dissector, data_end),
8499 si->dst_reg, si->src_reg,
8500 offsetof(struct bpf_flow_dissector, data_end));
8501 break;
8502
8503 case offsetof(struct __sk_buff, flow_keys):
8504 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_flow_dissector, flow_keys),
8505 si->dst_reg, si->src_reg,
8506 offsetof(struct bpf_flow_dissector, flow_keys));
8507 break;
8508 }
8509
8510 return insn - insn_buf;
8511 }
8512
bpf_convert_shinfo_access(const struct bpf_insn * si,struct bpf_insn * insn)8513 static struct bpf_insn *bpf_convert_shinfo_access(const struct bpf_insn *si,
8514 struct bpf_insn *insn)
8515 {
8516 /* si->dst_reg = skb_shinfo(SKB); */
8517 #ifdef NET_SKBUFF_DATA_USES_OFFSET
8518 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, end),
8519 BPF_REG_AX, si->src_reg,
8520 offsetof(struct sk_buff, end));
8521 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, head),
8522 si->dst_reg, si->src_reg,
8523 offsetof(struct sk_buff, head));
8524 *insn++ = BPF_ALU64_REG(BPF_ADD, si->dst_reg, BPF_REG_AX);
8525 #else
8526 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, end),
8527 si->dst_reg, si->src_reg,
8528 offsetof(struct sk_buff, end));
8529 #endif
8530
8531 return insn;
8532 }
8533
bpf_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)8534 static u32 bpf_convert_ctx_access(enum bpf_access_type type,
8535 const struct bpf_insn *si,
8536 struct bpf_insn *insn_buf,
8537 struct bpf_prog *prog, u32 *target_size)
8538 {
8539 struct bpf_insn *insn = insn_buf;
8540 int off;
8541
8542 switch (si->off) {
8543 case offsetof(struct __sk_buff, len):
8544 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
8545 bpf_target_off(struct sk_buff, len, 4,
8546 target_size));
8547 break;
8548
8549 case offsetof(struct __sk_buff, protocol):
8550 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
8551 bpf_target_off(struct sk_buff, protocol, 2,
8552 target_size));
8553 break;
8554
8555 case offsetof(struct __sk_buff, vlan_proto):
8556 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
8557 bpf_target_off(struct sk_buff, vlan_proto, 2,
8558 target_size));
8559 break;
8560
8561 case offsetof(struct __sk_buff, priority):
8562 if (type == BPF_WRITE)
8563 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
8564 bpf_target_off(struct sk_buff, priority, 4,
8565 target_size));
8566 else
8567 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
8568 bpf_target_off(struct sk_buff, priority, 4,
8569 target_size));
8570 break;
8571
8572 case offsetof(struct __sk_buff, ingress_ifindex):
8573 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
8574 bpf_target_off(struct sk_buff, skb_iif, 4,
8575 target_size));
8576 break;
8577
8578 case offsetof(struct __sk_buff, ifindex):
8579 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
8580 si->dst_reg, si->src_reg,
8581 offsetof(struct sk_buff, dev));
8582 *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
8583 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
8584 bpf_target_off(struct net_device, ifindex, 4,
8585 target_size));
8586 break;
8587
8588 case offsetof(struct __sk_buff, hash):
8589 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
8590 bpf_target_off(struct sk_buff, hash, 4,
8591 target_size));
8592 break;
8593
8594 case offsetof(struct __sk_buff, mark):
8595 if (type == BPF_WRITE)
8596 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
8597 bpf_target_off(struct sk_buff, mark, 4,
8598 target_size));
8599 else
8600 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
8601 bpf_target_off(struct sk_buff, mark, 4,
8602 target_size));
8603 break;
8604
8605 case offsetof(struct __sk_buff, pkt_type):
8606 *target_size = 1;
8607 *insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->src_reg,
8608 PKT_TYPE_OFFSET());
8609 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, PKT_TYPE_MAX);
8610 #ifdef __BIG_ENDIAN_BITFIELD
8611 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 5);
8612 #endif
8613 break;
8614
8615 case offsetof(struct __sk_buff, queue_mapping):
8616 if (type == BPF_WRITE) {
8617 *insn++ = BPF_JMP_IMM(BPF_JGE, si->src_reg, NO_QUEUE_MAPPING, 1);
8618 *insn++ = BPF_STX_MEM(BPF_H, si->dst_reg, si->src_reg,
8619 bpf_target_off(struct sk_buff,
8620 queue_mapping,
8621 2, target_size));
8622 } else {
8623 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
8624 bpf_target_off(struct sk_buff,
8625 queue_mapping,
8626 2, target_size));
8627 }
8628 break;
8629
8630 case offsetof(struct __sk_buff, vlan_present):
8631 *target_size = 1;
8632 *insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->src_reg,
8633 PKT_VLAN_PRESENT_OFFSET());
8634 if (PKT_VLAN_PRESENT_BIT)
8635 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, PKT_VLAN_PRESENT_BIT);
8636 if (PKT_VLAN_PRESENT_BIT < 7)
8637 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, 1);
8638 break;
8639
8640 case offsetof(struct __sk_buff, vlan_tci):
8641 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
8642 bpf_target_off(struct sk_buff, vlan_tci, 2,
8643 target_size));
8644 break;
8645
8646 case offsetof(struct __sk_buff, cb[0]) ...
8647 offsetofend(struct __sk_buff, cb[4]) - 1:
8648 BUILD_BUG_ON(sizeof_field(struct qdisc_skb_cb, data) < 20);
8649 BUILD_BUG_ON((offsetof(struct sk_buff, cb) +
8650 offsetof(struct qdisc_skb_cb, data)) %
8651 sizeof(__u64));
8652
8653 prog->cb_access = 1;
8654 off = si->off;
8655 off -= offsetof(struct __sk_buff, cb[0]);
8656 off += offsetof(struct sk_buff, cb);
8657 off += offsetof(struct qdisc_skb_cb, data);
8658 if (type == BPF_WRITE)
8659 *insn++ = BPF_STX_MEM(BPF_SIZE(si->code), si->dst_reg,
8660 si->src_reg, off);
8661 else
8662 *insn++ = BPF_LDX_MEM(BPF_SIZE(si->code), si->dst_reg,
8663 si->src_reg, off);
8664 break;
8665
8666 case offsetof(struct __sk_buff, tc_classid):
8667 BUILD_BUG_ON(sizeof_field(struct qdisc_skb_cb, tc_classid) != 2);
8668
8669 off = si->off;
8670 off -= offsetof(struct __sk_buff, tc_classid);
8671 off += offsetof(struct sk_buff, cb);
8672 off += offsetof(struct qdisc_skb_cb, tc_classid);
8673 *target_size = 2;
8674 if (type == BPF_WRITE)
8675 *insn++ = BPF_STX_MEM(BPF_H, si->dst_reg,
8676 si->src_reg, off);
8677 else
8678 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg,
8679 si->src_reg, off);
8680 break;
8681
8682 case offsetof(struct __sk_buff, data):
8683 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
8684 si->dst_reg, si->src_reg,
8685 offsetof(struct sk_buff, data));
8686 break;
8687
8688 case offsetof(struct __sk_buff, data_meta):
8689 off = si->off;
8690 off -= offsetof(struct __sk_buff, data_meta);
8691 off += offsetof(struct sk_buff, cb);
8692 off += offsetof(struct bpf_skb_data_end, data_meta);
8693 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
8694 si->src_reg, off);
8695 break;
8696
8697 case offsetof(struct __sk_buff, data_end):
8698 off = si->off;
8699 off -= offsetof(struct __sk_buff, data_end);
8700 off += offsetof(struct sk_buff, cb);
8701 off += offsetof(struct bpf_skb_data_end, data_end);
8702 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
8703 si->src_reg, off);
8704 break;
8705
8706 case offsetof(struct __sk_buff, tc_index):
8707 #ifdef CONFIG_NET_SCHED
8708 if (type == BPF_WRITE)
8709 *insn++ = BPF_STX_MEM(BPF_H, si->dst_reg, si->src_reg,
8710 bpf_target_off(struct sk_buff, tc_index, 2,
8711 target_size));
8712 else
8713 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
8714 bpf_target_off(struct sk_buff, tc_index, 2,
8715 target_size));
8716 #else
8717 *target_size = 2;
8718 if (type == BPF_WRITE)
8719 *insn++ = BPF_MOV64_REG(si->dst_reg, si->dst_reg);
8720 else
8721 *insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
8722 #endif
8723 break;
8724
8725 case offsetof(struct __sk_buff, napi_id):
8726 #if defined(CONFIG_NET_RX_BUSY_POLL)
8727 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
8728 bpf_target_off(struct sk_buff, napi_id, 4,
8729 target_size));
8730 *insn++ = BPF_JMP_IMM(BPF_JGE, si->dst_reg, MIN_NAPI_ID, 1);
8731 *insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
8732 #else
8733 *target_size = 4;
8734 *insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
8735 #endif
8736 break;
8737 case offsetof(struct __sk_buff, family):
8738 BUILD_BUG_ON(sizeof_field(struct sock_common, skc_family) != 2);
8739
8740 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
8741 si->dst_reg, si->src_reg,
8742 offsetof(struct sk_buff, sk));
8743 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
8744 bpf_target_off(struct sock_common,
8745 skc_family,
8746 2, target_size));
8747 break;
8748 case offsetof(struct __sk_buff, remote_ip4):
8749 BUILD_BUG_ON(sizeof_field(struct sock_common, skc_daddr) != 4);
8750
8751 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
8752 si->dst_reg, si->src_reg,
8753 offsetof(struct sk_buff, sk));
8754 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
8755 bpf_target_off(struct sock_common,
8756 skc_daddr,
8757 4, target_size));
8758 break;
8759 case offsetof(struct __sk_buff, local_ip4):
8760 BUILD_BUG_ON(sizeof_field(struct sock_common,
8761 skc_rcv_saddr) != 4);
8762
8763 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
8764 si->dst_reg, si->src_reg,
8765 offsetof(struct sk_buff, sk));
8766 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
8767 bpf_target_off(struct sock_common,
8768 skc_rcv_saddr,
8769 4, target_size));
8770 break;
8771 case offsetof(struct __sk_buff, remote_ip6[0]) ...
8772 offsetof(struct __sk_buff, remote_ip6[3]):
8773 #if IS_ENABLED(CONFIG_IPV6)
8774 BUILD_BUG_ON(sizeof_field(struct sock_common,
8775 skc_v6_daddr.s6_addr32[0]) != 4);
8776
8777 off = si->off;
8778 off -= offsetof(struct __sk_buff, remote_ip6[0]);
8779
8780 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
8781 si->dst_reg, si->src_reg,
8782 offsetof(struct sk_buff, sk));
8783 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
8784 offsetof(struct sock_common,
8785 skc_v6_daddr.s6_addr32[0]) +
8786 off);
8787 #else
8788 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
8789 #endif
8790 break;
8791 case offsetof(struct __sk_buff, local_ip6[0]) ...
8792 offsetof(struct __sk_buff, local_ip6[3]):
8793 #if IS_ENABLED(CONFIG_IPV6)
8794 BUILD_BUG_ON(sizeof_field(struct sock_common,
8795 skc_v6_rcv_saddr.s6_addr32[0]) != 4);
8796
8797 off = si->off;
8798 off -= offsetof(struct __sk_buff, local_ip6[0]);
8799
8800 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
8801 si->dst_reg, si->src_reg,
8802 offsetof(struct sk_buff, sk));
8803 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
8804 offsetof(struct sock_common,
8805 skc_v6_rcv_saddr.s6_addr32[0]) +
8806 off);
8807 #else
8808 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
8809 #endif
8810 break;
8811
8812 case offsetof(struct __sk_buff, remote_port):
8813 BUILD_BUG_ON(sizeof_field(struct sock_common, skc_dport) != 2);
8814
8815 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
8816 si->dst_reg, si->src_reg,
8817 offsetof(struct sk_buff, sk));
8818 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
8819 bpf_target_off(struct sock_common,
8820 skc_dport,
8821 2, target_size));
8822 #ifndef __BIG_ENDIAN_BITFIELD
8823 *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
8824 #endif
8825 break;
8826
8827 case offsetof(struct __sk_buff, local_port):
8828 BUILD_BUG_ON(sizeof_field(struct sock_common, skc_num) != 2);
8829
8830 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
8831 si->dst_reg, si->src_reg,
8832 offsetof(struct sk_buff, sk));
8833 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
8834 bpf_target_off(struct sock_common,
8835 skc_num, 2, target_size));
8836 break;
8837
8838 case offsetof(struct __sk_buff, tstamp):
8839 BUILD_BUG_ON(sizeof_field(struct sk_buff, tstamp) != 8);
8840
8841 if (type == BPF_WRITE)
8842 *insn++ = BPF_STX_MEM(BPF_DW,
8843 si->dst_reg, si->src_reg,
8844 bpf_target_off(struct sk_buff,
8845 tstamp, 8,
8846 target_size));
8847 else
8848 *insn++ = BPF_LDX_MEM(BPF_DW,
8849 si->dst_reg, si->src_reg,
8850 bpf_target_off(struct sk_buff,
8851 tstamp, 8,
8852 target_size));
8853 break;
8854
8855 case offsetof(struct __sk_buff, gso_segs):
8856 insn = bpf_convert_shinfo_access(si, insn);
8857 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct skb_shared_info, gso_segs),
8858 si->dst_reg, si->dst_reg,
8859 bpf_target_off(struct skb_shared_info,
8860 gso_segs, 2,
8861 target_size));
8862 break;
8863 case offsetof(struct __sk_buff, gso_size):
8864 insn = bpf_convert_shinfo_access(si, insn);
8865 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct skb_shared_info, gso_size),
8866 si->dst_reg, si->dst_reg,
8867 bpf_target_off(struct skb_shared_info,
8868 gso_size, 2,
8869 target_size));
8870 break;
8871 case offsetof(struct __sk_buff, wire_len):
8872 BUILD_BUG_ON(sizeof_field(struct qdisc_skb_cb, pkt_len) != 4);
8873
8874 off = si->off;
8875 off -= offsetof(struct __sk_buff, wire_len);
8876 off += offsetof(struct sk_buff, cb);
8877 off += offsetof(struct qdisc_skb_cb, pkt_len);
8878 *target_size = 4;
8879 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, off);
8880 break;
8881
8882 case offsetof(struct __sk_buff, sk):
8883 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
8884 si->dst_reg, si->src_reg,
8885 offsetof(struct sk_buff, sk));
8886 break;
8887 }
8888
8889 return insn - insn_buf;
8890 }
8891
bpf_sock_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)8892 u32 bpf_sock_convert_ctx_access(enum bpf_access_type type,
8893 const struct bpf_insn *si,
8894 struct bpf_insn *insn_buf,
8895 struct bpf_prog *prog, u32 *target_size)
8896 {
8897 struct bpf_insn *insn = insn_buf;
8898 int off;
8899
8900 switch (si->off) {
8901 case offsetof(struct bpf_sock, bound_dev_if):
8902 BUILD_BUG_ON(sizeof_field(struct sock, sk_bound_dev_if) != 4);
8903
8904 if (type == BPF_WRITE)
8905 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
8906 offsetof(struct sock, sk_bound_dev_if));
8907 else
8908 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
8909 offsetof(struct sock, sk_bound_dev_if));
8910 break;
8911
8912 case offsetof(struct bpf_sock, mark):
8913 BUILD_BUG_ON(sizeof_field(struct sock, sk_mark) != 4);
8914
8915 if (type == BPF_WRITE)
8916 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
8917 offsetof(struct sock, sk_mark));
8918 else
8919 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
8920 offsetof(struct sock, sk_mark));
8921 break;
8922
8923 case offsetof(struct bpf_sock, priority):
8924 BUILD_BUG_ON(sizeof_field(struct sock, sk_priority) != 4);
8925
8926 if (type == BPF_WRITE)
8927 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
8928 offsetof(struct sock, sk_priority));
8929 else
8930 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
8931 offsetof(struct sock, sk_priority));
8932 break;
8933
8934 case offsetof(struct bpf_sock, family):
8935 *insn++ = BPF_LDX_MEM(
8936 BPF_FIELD_SIZEOF(struct sock_common, skc_family),
8937 si->dst_reg, si->src_reg,
8938 bpf_target_off(struct sock_common,
8939 skc_family,
8940 sizeof_field(struct sock_common,
8941 skc_family),
8942 target_size));
8943 break;
8944
8945 case offsetof(struct bpf_sock, type):
8946 *insn++ = BPF_LDX_MEM(
8947 BPF_FIELD_SIZEOF(struct sock, sk_type),
8948 si->dst_reg, si->src_reg,
8949 bpf_target_off(struct sock, sk_type,
8950 sizeof_field(struct sock, sk_type),
8951 target_size));
8952 break;
8953
8954 case offsetof(struct bpf_sock, protocol):
8955 *insn++ = BPF_LDX_MEM(
8956 BPF_FIELD_SIZEOF(struct sock, sk_protocol),
8957 si->dst_reg, si->src_reg,
8958 bpf_target_off(struct sock, sk_protocol,
8959 sizeof_field(struct sock, sk_protocol),
8960 target_size));
8961 break;
8962
8963 case offsetof(struct bpf_sock, src_ip4):
8964 *insn++ = BPF_LDX_MEM(
8965 BPF_SIZE(si->code), si->dst_reg, si->src_reg,
8966 bpf_target_off(struct sock_common, skc_rcv_saddr,
8967 sizeof_field(struct sock_common,
8968 skc_rcv_saddr),
8969 target_size));
8970 break;
8971
8972 case offsetof(struct bpf_sock, dst_ip4):
8973 *insn++ = BPF_LDX_MEM(
8974 BPF_SIZE(si->code), si->dst_reg, si->src_reg,
8975 bpf_target_off(struct sock_common, skc_daddr,
8976 sizeof_field(struct sock_common,
8977 skc_daddr),
8978 target_size));
8979 break;
8980
8981 case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]):
8982 #if IS_ENABLED(CONFIG_IPV6)
8983 off = si->off;
8984 off -= offsetof(struct bpf_sock, src_ip6[0]);
8985 *insn++ = BPF_LDX_MEM(
8986 BPF_SIZE(si->code), si->dst_reg, si->src_reg,
8987 bpf_target_off(
8988 struct sock_common,
8989 skc_v6_rcv_saddr.s6_addr32[0],
8990 sizeof_field(struct sock_common,
8991 skc_v6_rcv_saddr.s6_addr32[0]),
8992 target_size) + off);
8993 #else
8994 (void)off;
8995 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
8996 #endif
8997 break;
8998
8999 case bpf_ctx_range_till(struct bpf_sock, dst_ip6[0], dst_ip6[3]):
9000 #if IS_ENABLED(CONFIG_IPV6)
9001 off = si->off;
9002 off -= offsetof(struct bpf_sock, dst_ip6[0]);
9003 *insn++ = BPF_LDX_MEM(
9004 BPF_SIZE(si->code), si->dst_reg, si->src_reg,
9005 bpf_target_off(struct sock_common,
9006 skc_v6_daddr.s6_addr32[0],
9007 sizeof_field(struct sock_common,
9008 skc_v6_daddr.s6_addr32[0]),
9009 target_size) + off);
9010 #else
9011 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
9012 *target_size = 4;
9013 #endif
9014 break;
9015
9016 case offsetof(struct bpf_sock, src_port):
9017 *insn++ = BPF_LDX_MEM(
9018 BPF_FIELD_SIZEOF(struct sock_common, skc_num),
9019 si->dst_reg, si->src_reg,
9020 bpf_target_off(struct sock_common, skc_num,
9021 sizeof_field(struct sock_common,
9022 skc_num),
9023 target_size));
9024 break;
9025
9026 case offsetof(struct bpf_sock, dst_port):
9027 *insn++ = BPF_LDX_MEM(
9028 BPF_FIELD_SIZEOF(struct sock_common, skc_dport),
9029 si->dst_reg, si->src_reg,
9030 bpf_target_off(struct sock_common, skc_dport,
9031 sizeof_field(struct sock_common,
9032 skc_dport),
9033 target_size));
9034 break;
9035
9036 case offsetof(struct bpf_sock, state):
9037 *insn++ = BPF_LDX_MEM(
9038 BPF_FIELD_SIZEOF(struct sock_common, skc_state),
9039 si->dst_reg, si->src_reg,
9040 bpf_target_off(struct sock_common, skc_state,
9041 sizeof_field(struct sock_common,
9042 skc_state),
9043 target_size));
9044 break;
9045 case offsetof(struct bpf_sock, rx_queue_mapping):
9046 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
9047 *insn++ = BPF_LDX_MEM(
9048 BPF_FIELD_SIZEOF(struct sock, sk_rx_queue_mapping),
9049 si->dst_reg, si->src_reg,
9050 bpf_target_off(struct sock, sk_rx_queue_mapping,
9051 sizeof_field(struct sock,
9052 sk_rx_queue_mapping),
9053 target_size));
9054 *insn++ = BPF_JMP_IMM(BPF_JNE, si->dst_reg, NO_QUEUE_MAPPING,
9055 1);
9056 *insn++ = BPF_MOV64_IMM(si->dst_reg, -1);
9057 #else
9058 *insn++ = BPF_MOV64_IMM(si->dst_reg, -1);
9059 *target_size = 2;
9060 #endif
9061 break;
9062 }
9063
9064 return insn - insn_buf;
9065 }
9066
tc_cls_act_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)9067 static u32 tc_cls_act_convert_ctx_access(enum bpf_access_type type,
9068 const struct bpf_insn *si,
9069 struct bpf_insn *insn_buf,
9070 struct bpf_prog *prog, u32 *target_size)
9071 {
9072 struct bpf_insn *insn = insn_buf;
9073
9074 switch (si->off) {
9075 case offsetof(struct __sk_buff, ifindex):
9076 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
9077 si->dst_reg, si->src_reg,
9078 offsetof(struct sk_buff, dev));
9079 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9080 bpf_target_off(struct net_device, ifindex, 4,
9081 target_size));
9082 break;
9083 default:
9084 return bpf_convert_ctx_access(type, si, insn_buf, prog,
9085 target_size);
9086 }
9087
9088 return insn - insn_buf;
9089 }
9090
xdp_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)9091 static u32 xdp_convert_ctx_access(enum bpf_access_type type,
9092 const struct bpf_insn *si,
9093 struct bpf_insn *insn_buf,
9094 struct bpf_prog *prog, u32 *target_size)
9095 {
9096 struct bpf_insn *insn = insn_buf;
9097
9098 switch (si->off) {
9099 case offsetof(struct xdp_md, data):
9100 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data),
9101 si->dst_reg, si->src_reg,
9102 offsetof(struct xdp_buff, data));
9103 break;
9104 case offsetof(struct xdp_md, data_meta):
9105 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_meta),
9106 si->dst_reg, si->src_reg,
9107 offsetof(struct xdp_buff, data_meta));
9108 break;
9109 case offsetof(struct xdp_md, data_end):
9110 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_end),
9111 si->dst_reg, si->src_reg,
9112 offsetof(struct xdp_buff, data_end));
9113 break;
9114 case offsetof(struct xdp_md, ingress_ifindex):
9115 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, rxq),
9116 si->dst_reg, si->src_reg,
9117 offsetof(struct xdp_buff, rxq));
9118 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_rxq_info, dev),
9119 si->dst_reg, si->dst_reg,
9120 offsetof(struct xdp_rxq_info, dev));
9121 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9122 offsetof(struct net_device, ifindex));
9123 break;
9124 case offsetof(struct xdp_md, rx_queue_index):
9125 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, rxq),
9126 si->dst_reg, si->src_reg,
9127 offsetof(struct xdp_buff, rxq));
9128 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9129 offsetof(struct xdp_rxq_info,
9130 queue_index));
9131 break;
9132 case offsetof(struct xdp_md, egress_ifindex):
9133 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, txq),
9134 si->dst_reg, si->src_reg,
9135 offsetof(struct xdp_buff, txq));
9136 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_txq_info, dev),
9137 si->dst_reg, si->dst_reg,
9138 offsetof(struct xdp_txq_info, dev));
9139 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9140 offsetof(struct net_device, ifindex));
9141 break;
9142 }
9143
9144 return insn - insn_buf;
9145 }
9146
9147 /* SOCK_ADDR_LOAD_NESTED_FIELD() loads Nested Field S.F.NF where S is type of
9148 * context Structure, F is Field in context structure that contains a pointer
9149 * to Nested Structure of type NS that has the field NF.
9150 *
9151 * SIZE encodes the load size (BPF_B, BPF_H, etc). It's up to caller to make
9152 * sure that SIZE is not greater than actual size of S.F.NF.
9153 *
9154 * If offset OFF is provided, the load happens from that offset relative to
9155 * offset of NF.
9156 */
9157 #define SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, SIZE, OFF) \
9158 do { \
9159 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(S, F), si->dst_reg, \
9160 si->src_reg, offsetof(S, F)); \
9161 *insn++ = BPF_LDX_MEM( \
9162 SIZE, si->dst_reg, si->dst_reg, \
9163 bpf_target_off(NS, NF, sizeof_field(NS, NF), \
9164 target_size) \
9165 + OFF); \
9166 } while (0)
9167
9168 #define SOCK_ADDR_LOAD_NESTED_FIELD(S, NS, F, NF) \
9169 SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, \
9170 BPF_FIELD_SIZEOF(NS, NF), 0)
9171
9172 /* SOCK_ADDR_STORE_NESTED_FIELD_OFF() has semantic similar to
9173 * SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF() but for store operation.
9174 *
9175 * In addition it uses Temporary Field TF (member of struct S) as the 3rd
9176 * "register" since two registers available in convert_ctx_access are not
9177 * enough: we can't override neither SRC, since it contains value to store, nor
9178 * DST since it contains pointer to context that may be used by later
9179 * instructions. But we need a temporary place to save pointer to nested
9180 * structure whose field we want to store to.
9181 */
9182 #define SOCK_ADDR_STORE_NESTED_FIELD_OFF(S, NS, F, NF, SIZE, OFF, TF) \
9183 do { \
9184 int tmp_reg = BPF_REG_9; \
9185 if (si->src_reg == tmp_reg || si->dst_reg == tmp_reg) \
9186 --tmp_reg; \
9187 if (si->src_reg == tmp_reg || si->dst_reg == tmp_reg) \
9188 --tmp_reg; \
9189 *insn++ = BPF_STX_MEM(BPF_DW, si->dst_reg, tmp_reg, \
9190 offsetof(S, TF)); \
9191 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(S, F), tmp_reg, \
9192 si->dst_reg, offsetof(S, F)); \
9193 *insn++ = BPF_STX_MEM(SIZE, tmp_reg, si->src_reg, \
9194 bpf_target_off(NS, NF, sizeof_field(NS, NF), \
9195 target_size) \
9196 + OFF); \
9197 *insn++ = BPF_LDX_MEM(BPF_DW, tmp_reg, si->dst_reg, \
9198 offsetof(S, TF)); \
9199 } while (0)
9200
9201 #define SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, SIZE, OFF, \
9202 TF) \
9203 do { \
9204 if (type == BPF_WRITE) { \
9205 SOCK_ADDR_STORE_NESTED_FIELD_OFF(S, NS, F, NF, SIZE, \
9206 OFF, TF); \
9207 } else { \
9208 SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF( \
9209 S, NS, F, NF, SIZE, OFF); \
9210 } \
9211 } while (0)
9212
9213 #define SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD(S, NS, F, NF, TF) \
9214 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF( \
9215 S, NS, F, NF, BPF_FIELD_SIZEOF(NS, NF), 0, TF)
9216
sock_addr_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)9217 static u32 sock_addr_convert_ctx_access(enum bpf_access_type type,
9218 const struct bpf_insn *si,
9219 struct bpf_insn *insn_buf,
9220 struct bpf_prog *prog, u32 *target_size)
9221 {
9222 int off, port_size = sizeof_field(struct sockaddr_in6, sin6_port);
9223 struct bpf_insn *insn = insn_buf;
9224
9225 switch (si->off) {
9226 case offsetof(struct bpf_sock_addr, user_family):
9227 SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern,
9228 struct sockaddr, uaddr, sa_family);
9229 break;
9230
9231 case offsetof(struct bpf_sock_addr, user_ip4):
9232 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
9233 struct bpf_sock_addr_kern, struct sockaddr_in, uaddr,
9234 sin_addr, BPF_SIZE(si->code), 0, tmp_reg);
9235 break;
9236
9237 case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]):
9238 off = si->off;
9239 off -= offsetof(struct bpf_sock_addr, user_ip6[0]);
9240 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
9241 struct bpf_sock_addr_kern, struct sockaddr_in6, uaddr,
9242 sin6_addr.s6_addr32[0], BPF_SIZE(si->code), off,
9243 tmp_reg);
9244 break;
9245
9246 case offsetof(struct bpf_sock_addr, user_port):
9247 /* To get port we need to know sa_family first and then treat
9248 * sockaddr as either sockaddr_in or sockaddr_in6.
9249 * Though we can simplify since port field has same offset and
9250 * size in both structures.
9251 * Here we check this invariant and use just one of the
9252 * structures if it's true.
9253 */
9254 BUILD_BUG_ON(offsetof(struct sockaddr_in, sin_port) !=
9255 offsetof(struct sockaddr_in6, sin6_port));
9256 BUILD_BUG_ON(sizeof_field(struct sockaddr_in, sin_port) !=
9257 sizeof_field(struct sockaddr_in6, sin6_port));
9258 /* Account for sin6_port being smaller than user_port. */
9259 port_size = min(port_size, BPF_LDST_BYTES(si));
9260 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
9261 struct bpf_sock_addr_kern, struct sockaddr_in6, uaddr,
9262 sin6_port, bytes_to_bpf_size(port_size), 0, tmp_reg);
9263 break;
9264
9265 case offsetof(struct bpf_sock_addr, family):
9266 SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern,
9267 struct sock, sk, sk_family);
9268 break;
9269
9270 case offsetof(struct bpf_sock_addr, type):
9271 SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern,
9272 struct sock, sk, sk_type);
9273 break;
9274
9275 case offsetof(struct bpf_sock_addr, protocol):
9276 SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern,
9277 struct sock, sk, sk_protocol);
9278 break;
9279
9280 case offsetof(struct bpf_sock_addr, msg_src_ip4):
9281 /* Treat t_ctx as struct in_addr for msg_src_ip4. */
9282 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
9283 struct bpf_sock_addr_kern, struct in_addr, t_ctx,
9284 s_addr, BPF_SIZE(si->code), 0, tmp_reg);
9285 break;
9286
9287 case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0],
9288 msg_src_ip6[3]):
9289 off = si->off;
9290 off -= offsetof(struct bpf_sock_addr, msg_src_ip6[0]);
9291 /* Treat t_ctx as struct in6_addr for msg_src_ip6. */
9292 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
9293 struct bpf_sock_addr_kern, struct in6_addr, t_ctx,
9294 s6_addr32[0], BPF_SIZE(si->code), off, tmp_reg);
9295 break;
9296 case offsetof(struct bpf_sock_addr, sk):
9297 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_addr_kern, sk),
9298 si->dst_reg, si->src_reg,
9299 offsetof(struct bpf_sock_addr_kern, sk));
9300 break;
9301 }
9302
9303 return insn - insn_buf;
9304 }
9305
sock_ops_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)9306 static u32 sock_ops_convert_ctx_access(enum bpf_access_type type,
9307 const struct bpf_insn *si,
9308 struct bpf_insn *insn_buf,
9309 struct bpf_prog *prog,
9310 u32 *target_size)
9311 {
9312 struct bpf_insn *insn = insn_buf;
9313 int off;
9314
9315 /* Helper macro for adding read access to tcp_sock or sock fields. */
9316 #define SOCK_OPS_GET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ) \
9317 do { \
9318 int fullsock_reg = si->dst_reg, reg = BPF_REG_9, jmp = 2; \
9319 BUILD_BUG_ON(sizeof_field(OBJ, OBJ_FIELD) > \
9320 sizeof_field(struct bpf_sock_ops, BPF_FIELD)); \
9321 if (si->dst_reg == reg || si->src_reg == reg) \
9322 reg--; \
9323 if (si->dst_reg == reg || si->src_reg == reg) \
9324 reg--; \
9325 if (si->dst_reg == si->src_reg) { \
9326 *insn++ = BPF_STX_MEM(BPF_DW, si->src_reg, reg, \
9327 offsetof(struct bpf_sock_ops_kern, \
9328 temp)); \
9329 fullsock_reg = reg; \
9330 jmp += 2; \
9331 } \
9332 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \
9333 struct bpf_sock_ops_kern, \
9334 is_fullsock), \
9335 fullsock_reg, si->src_reg, \
9336 offsetof(struct bpf_sock_ops_kern, \
9337 is_fullsock)); \
9338 *insn++ = BPF_JMP_IMM(BPF_JEQ, fullsock_reg, 0, jmp); \
9339 if (si->dst_reg == si->src_reg) \
9340 *insn++ = BPF_LDX_MEM(BPF_DW, reg, si->src_reg, \
9341 offsetof(struct bpf_sock_ops_kern, \
9342 temp)); \
9343 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \
9344 struct bpf_sock_ops_kern, sk),\
9345 si->dst_reg, si->src_reg, \
9346 offsetof(struct bpf_sock_ops_kern, sk));\
9347 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(OBJ, \
9348 OBJ_FIELD), \
9349 si->dst_reg, si->dst_reg, \
9350 offsetof(OBJ, OBJ_FIELD)); \
9351 if (si->dst_reg == si->src_reg) { \
9352 *insn++ = BPF_JMP_A(1); \
9353 *insn++ = BPF_LDX_MEM(BPF_DW, reg, si->src_reg, \
9354 offsetof(struct bpf_sock_ops_kern, \
9355 temp)); \
9356 } \
9357 } while (0)
9358
9359 #define SOCK_OPS_GET_SK() \
9360 do { \
9361 int fullsock_reg = si->dst_reg, reg = BPF_REG_9, jmp = 1; \
9362 if (si->dst_reg == reg || si->src_reg == reg) \
9363 reg--; \
9364 if (si->dst_reg == reg || si->src_reg == reg) \
9365 reg--; \
9366 if (si->dst_reg == si->src_reg) { \
9367 *insn++ = BPF_STX_MEM(BPF_DW, si->src_reg, reg, \
9368 offsetof(struct bpf_sock_ops_kern, \
9369 temp)); \
9370 fullsock_reg = reg; \
9371 jmp += 2; \
9372 } \
9373 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \
9374 struct bpf_sock_ops_kern, \
9375 is_fullsock), \
9376 fullsock_reg, si->src_reg, \
9377 offsetof(struct bpf_sock_ops_kern, \
9378 is_fullsock)); \
9379 *insn++ = BPF_JMP_IMM(BPF_JEQ, fullsock_reg, 0, jmp); \
9380 if (si->dst_reg == si->src_reg) \
9381 *insn++ = BPF_LDX_MEM(BPF_DW, reg, si->src_reg, \
9382 offsetof(struct bpf_sock_ops_kern, \
9383 temp)); \
9384 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \
9385 struct bpf_sock_ops_kern, sk),\
9386 si->dst_reg, si->src_reg, \
9387 offsetof(struct bpf_sock_ops_kern, sk));\
9388 if (si->dst_reg == si->src_reg) { \
9389 *insn++ = BPF_JMP_A(1); \
9390 *insn++ = BPF_LDX_MEM(BPF_DW, reg, si->src_reg, \
9391 offsetof(struct bpf_sock_ops_kern, \
9392 temp)); \
9393 } \
9394 } while (0)
9395
9396 #define SOCK_OPS_GET_TCP_SOCK_FIELD(FIELD) \
9397 SOCK_OPS_GET_FIELD(FIELD, FIELD, struct tcp_sock)
9398
9399 /* Helper macro for adding write access to tcp_sock or sock fields.
9400 * The macro is called with two registers, dst_reg which contains a pointer
9401 * to ctx (context) and src_reg which contains the value that should be
9402 * stored. However, we need an additional register since we cannot overwrite
9403 * dst_reg because it may be used later in the program.
9404 * Instead we "borrow" one of the other register. We first save its value
9405 * into a new (temp) field in bpf_sock_ops_kern, use it, and then restore
9406 * it at the end of the macro.
9407 */
9408 #define SOCK_OPS_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ) \
9409 do { \
9410 int reg = BPF_REG_9; \
9411 BUILD_BUG_ON(sizeof_field(OBJ, OBJ_FIELD) > \
9412 sizeof_field(struct bpf_sock_ops, BPF_FIELD)); \
9413 if (si->dst_reg == reg || si->src_reg == reg) \
9414 reg--; \
9415 if (si->dst_reg == reg || si->src_reg == reg) \
9416 reg--; \
9417 *insn++ = BPF_STX_MEM(BPF_DW, si->dst_reg, reg, \
9418 offsetof(struct bpf_sock_ops_kern, \
9419 temp)); \
9420 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \
9421 struct bpf_sock_ops_kern, \
9422 is_fullsock), \
9423 reg, si->dst_reg, \
9424 offsetof(struct bpf_sock_ops_kern, \
9425 is_fullsock)); \
9426 *insn++ = BPF_JMP_IMM(BPF_JEQ, reg, 0, 2); \
9427 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \
9428 struct bpf_sock_ops_kern, sk),\
9429 reg, si->dst_reg, \
9430 offsetof(struct bpf_sock_ops_kern, sk));\
9431 *insn++ = BPF_STX_MEM(BPF_FIELD_SIZEOF(OBJ, OBJ_FIELD), \
9432 reg, si->src_reg, \
9433 offsetof(OBJ, OBJ_FIELD)); \
9434 *insn++ = BPF_LDX_MEM(BPF_DW, reg, si->dst_reg, \
9435 offsetof(struct bpf_sock_ops_kern, \
9436 temp)); \
9437 } while (0)
9438
9439 #define SOCK_OPS_GET_OR_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ, TYPE) \
9440 do { \
9441 if (TYPE == BPF_WRITE) \
9442 SOCK_OPS_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ); \
9443 else \
9444 SOCK_OPS_GET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ); \
9445 } while (0)
9446
9447 if (insn > insn_buf)
9448 return insn - insn_buf;
9449
9450 switch (si->off) {
9451 case offsetof(struct bpf_sock_ops, op):
9452 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
9453 op),
9454 si->dst_reg, si->src_reg,
9455 offsetof(struct bpf_sock_ops_kern, op));
9456 break;
9457
9458 case offsetof(struct bpf_sock_ops, replylong[0]) ...
9459 offsetof(struct bpf_sock_ops, replylong[3]):
9460 BUILD_BUG_ON(sizeof_field(struct bpf_sock_ops, reply) !=
9461 sizeof_field(struct bpf_sock_ops_kern, reply));
9462 BUILD_BUG_ON(sizeof_field(struct bpf_sock_ops, replylong) !=
9463 sizeof_field(struct bpf_sock_ops_kern, replylong));
9464 off = si->off;
9465 off -= offsetof(struct bpf_sock_ops, replylong[0]);
9466 off += offsetof(struct bpf_sock_ops_kern, replylong[0]);
9467 if (type == BPF_WRITE)
9468 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
9469 off);
9470 else
9471 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9472 off);
9473 break;
9474
9475 case offsetof(struct bpf_sock_ops, family):
9476 BUILD_BUG_ON(sizeof_field(struct sock_common, skc_family) != 2);
9477
9478 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
9479 struct bpf_sock_ops_kern, sk),
9480 si->dst_reg, si->src_reg,
9481 offsetof(struct bpf_sock_ops_kern, sk));
9482 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
9483 offsetof(struct sock_common, skc_family));
9484 break;
9485
9486 case offsetof(struct bpf_sock_ops, remote_ip4):
9487 BUILD_BUG_ON(sizeof_field(struct sock_common, skc_daddr) != 4);
9488
9489 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
9490 struct bpf_sock_ops_kern, sk),
9491 si->dst_reg, si->src_reg,
9492 offsetof(struct bpf_sock_ops_kern, sk));
9493 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9494 offsetof(struct sock_common, skc_daddr));
9495 break;
9496
9497 case offsetof(struct bpf_sock_ops, local_ip4):
9498 BUILD_BUG_ON(sizeof_field(struct sock_common,
9499 skc_rcv_saddr) != 4);
9500
9501 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
9502 struct bpf_sock_ops_kern, sk),
9503 si->dst_reg, si->src_reg,
9504 offsetof(struct bpf_sock_ops_kern, sk));
9505 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9506 offsetof(struct sock_common,
9507 skc_rcv_saddr));
9508 break;
9509
9510 case offsetof(struct bpf_sock_ops, remote_ip6[0]) ...
9511 offsetof(struct bpf_sock_ops, remote_ip6[3]):
9512 #if IS_ENABLED(CONFIG_IPV6)
9513 BUILD_BUG_ON(sizeof_field(struct sock_common,
9514 skc_v6_daddr.s6_addr32[0]) != 4);
9515
9516 off = si->off;
9517 off -= offsetof(struct bpf_sock_ops, remote_ip6[0]);
9518 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
9519 struct bpf_sock_ops_kern, sk),
9520 si->dst_reg, si->src_reg,
9521 offsetof(struct bpf_sock_ops_kern, sk));
9522 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9523 offsetof(struct sock_common,
9524 skc_v6_daddr.s6_addr32[0]) +
9525 off);
9526 #else
9527 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
9528 #endif
9529 break;
9530
9531 case offsetof(struct bpf_sock_ops, local_ip6[0]) ...
9532 offsetof(struct bpf_sock_ops, local_ip6[3]):
9533 #if IS_ENABLED(CONFIG_IPV6)
9534 BUILD_BUG_ON(sizeof_field(struct sock_common,
9535 skc_v6_rcv_saddr.s6_addr32[0]) != 4);
9536
9537 off = si->off;
9538 off -= offsetof(struct bpf_sock_ops, local_ip6[0]);
9539 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
9540 struct bpf_sock_ops_kern, sk),
9541 si->dst_reg, si->src_reg,
9542 offsetof(struct bpf_sock_ops_kern, sk));
9543 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9544 offsetof(struct sock_common,
9545 skc_v6_rcv_saddr.s6_addr32[0]) +
9546 off);
9547 #else
9548 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
9549 #endif
9550 break;
9551
9552 case offsetof(struct bpf_sock_ops, remote_port):
9553 BUILD_BUG_ON(sizeof_field(struct sock_common, skc_dport) != 2);
9554
9555 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
9556 struct bpf_sock_ops_kern, sk),
9557 si->dst_reg, si->src_reg,
9558 offsetof(struct bpf_sock_ops_kern, sk));
9559 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
9560 offsetof(struct sock_common, skc_dport));
9561 #ifndef __BIG_ENDIAN_BITFIELD
9562 *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
9563 #endif
9564 break;
9565
9566 case offsetof(struct bpf_sock_ops, local_port):
9567 BUILD_BUG_ON(sizeof_field(struct sock_common, skc_num) != 2);
9568
9569 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
9570 struct bpf_sock_ops_kern, sk),
9571 si->dst_reg, si->src_reg,
9572 offsetof(struct bpf_sock_ops_kern, sk));
9573 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
9574 offsetof(struct sock_common, skc_num));
9575 break;
9576
9577 case offsetof(struct bpf_sock_ops, is_fullsock):
9578 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
9579 struct bpf_sock_ops_kern,
9580 is_fullsock),
9581 si->dst_reg, si->src_reg,
9582 offsetof(struct bpf_sock_ops_kern,
9583 is_fullsock));
9584 break;
9585
9586 case offsetof(struct bpf_sock_ops, state):
9587 BUILD_BUG_ON(sizeof_field(struct sock_common, skc_state) != 1);
9588
9589 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
9590 struct bpf_sock_ops_kern, sk),
9591 si->dst_reg, si->src_reg,
9592 offsetof(struct bpf_sock_ops_kern, sk));
9593 *insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->dst_reg,
9594 offsetof(struct sock_common, skc_state));
9595 break;
9596
9597 case offsetof(struct bpf_sock_ops, rtt_min):
9598 BUILD_BUG_ON(sizeof_field(struct tcp_sock, rtt_min) !=
9599 sizeof(struct minmax));
9600 BUILD_BUG_ON(sizeof(struct minmax) <
9601 sizeof(struct minmax_sample));
9602
9603 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
9604 struct bpf_sock_ops_kern, sk),
9605 si->dst_reg, si->src_reg,
9606 offsetof(struct bpf_sock_ops_kern, sk));
9607 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9608 offsetof(struct tcp_sock, rtt_min) +
9609 sizeof_field(struct minmax_sample, t));
9610 break;
9611
9612 case offsetof(struct bpf_sock_ops, bpf_sock_ops_cb_flags):
9613 SOCK_OPS_GET_FIELD(bpf_sock_ops_cb_flags, bpf_sock_ops_cb_flags,
9614 struct tcp_sock);
9615 break;
9616
9617 case offsetof(struct bpf_sock_ops, sk_txhash):
9618 SOCK_OPS_GET_OR_SET_FIELD(sk_txhash, sk_txhash,
9619 struct sock, type);
9620 break;
9621 case offsetof(struct bpf_sock_ops, snd_cwnd):
9622 SOCK_OPS_GET_TCP_SOCK_FIELD(snd_cwnd);
9623 break;
9624 case offsetof(struct bpf_sock_ops, srtt_us):
9625 SOCK_OPS_GET_TCP_SOCK_FIELD(srtt_us);
9626 break;
9627 case offsetof(struct bpf_sock_ops, snd_ssthresh):
9628 SOCK_OPS_GET_TCP_SOCK_FIELD(snd_ssthresh);
9629 break;
9630 case offsetof(struct bpf_sock_ops, rcv_nxt):
9631 SOCK_OPS_GET_TCP_SOCK_FIELD(rcv_nxt);
9632 break;
9633 case offsetof(struct bpf_sock_ops, snd_nxt):
9634 SOCK_OPS_GET_TCP_SOCK_FIELD(snd_nxt);
9635 break;
9636 case offsetof(struct bpf_sock_ops, snd_una):
9637 SOCK_OPS_GET_TCP_SOCK_FIELD(snd_una);
9638 break;
9639 case offsetof(struct bpf_sock_ops, mss_cache):
9640 SOCK_OPS_GET_TCP_SOCK_FIELD(mss_cache);
9641 break;
9642 case offsetof(struct bpf_sock_ops, ecn_flags):
9643 SOCK_OPS_GET_TCP_SOCK_FIELD(ecn_flags);
9644 break;
9645 case offsetof(struct bpf_sock_ops, rate_delivered):
9646 SOCK_OPS_GET_TCP_SOCK_FIELD(rate_delivered);
9647 break;
9648 case offsetof(struct bpf_sock_ops, rate_interval_us):
9649 SOCK_OPS_GET_TCP_SOCK_FIELD(rate_interval_us);
9650 break;
9651 case offsetof(struct bpf_sock_ops, packets_out):
9652 SOCK_OPS_GET_TCP_SOCK_FIELD(packets_out);
9653 break;
9654 case offsetof(struct bpf_sock_ops, retrans_out):
9655 SOCK_OPS_GET_TCP_SOCK_FIELD(retrans_out);
9656 break;
9657 case offsetof(struct bpf_sock_ops, total_retrans):
9658 SOCK_OPS_GET_TCP_SOCK_FIELD(total_retrans);
9659 break;
9660 case offsetof(struct bpf_sock_ops, segs_in):
9661 SOCK_OPS_GET_TCP_SOCK_FIELD(segs_in);
9662 break;
9663 case offsetof(struct bpf_sock_ops, data_segs_in):
9664 SOCK_OPS_GET_TCP_SOCK_FIELD(data_segs_in);
9665 break;
9666 case offsetof(struct bpf_sock_ops, segs_out):
9667 SOCK_OPS_GET_TCP_SOCK_FIELD(segs_out);
9668 break;
9669 case offsetof(struct bpf_sock_ops, data_segs_out):
9670 SOCK_OPS_GET_TCP_SOCK_FIELD(data_segs_out);
9671 break;
9672 case offsetof(struct bpf_sock_ops, lost_out):
9673 SOCK_OPS_GET_TCP_SOCK_FIELD(lost_out);
9674 break;
9675 case offsetof(struct bpf_sock_ops, sacked_out):
9676 SOCK_OPS_GET_TCP_SOCK_FIELD(sacked_out);
9677 break;
9678 case offsetof(struct bpf_sock_ops, bytes_received):
9679 SOCK_OPS_GET_TCP_SOCK_FIELD(bytes_received);
9680 break;
9681 case offsetof(struct bpf_sock_ops, bytes_acked):
9682 SOCK_OPS_GET_TCP_SOCK_FIELD(bytes_acked);
9683 break;
9684 case offsetof(struct bpf_sock_ops, sk):
9685 SOCK_OPS_GET_SK();
9686 break;
9687 case offsetof(struct bpf_sock_ops, skb_data_end):
9688 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
9689 skb_data_end),
9690 si->dst_reg, si->src_reg,
9691 offsetof(struct bpf_sock_ops_kern,
9692 skb_data_end));
9693 break;
9694 case offsetof(struct bpf_sock_ops, skb_data):
9695 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
9696 skb),
9697 si->dst_reg, si->src_reg,
9698 offsetof(struct bpf_sock_ops_kern,
9699 skb));
9700 *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
9701 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
9702 si->dst_reg, si->dst_reg,
9703 offsetof(struct sk_buff, data));
9704 break;
9705 case offsetof(struct bpf_sock_ops, skb_len):
9706 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
9707 skb),
9708 si->dst_reg, si->src_reg,
9709 offsetof(struct bpf_sock_ops_kern,
9710 skb));
9711 *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
9712 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, len),
9713 si->dst_reg, si->dst_reg,
9714 offsetof(struct sk_buff, len));
9715 break;
9716 case offsetof(struct bpf_sock_ops, skb_tcp_flags):
9717 off = offsetof(struct sk_buff, cb);
9718 off += offsetof(struct tcp_skb_cb, tcp_flags);
9719 *target_size = sizeof_field(struct tcp_skb_cb, tcp_flags);
9720 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
9721 skb),
9722 si->dst_reg, si->src_reg,
9723 offsetof(struct bpf_sock_ops_kern,
9724 skb));
9725 *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
9726 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct tcp_skb_cb,
9727 tcp_flags),
9728 si->dst_reg, si->dst_reg, off);
9729 break;
9730 }
9731 return insn - insn_buf;
9732 }
9733
9734 /* data_end = skb->data + skb_headlen() */
bpf_convert_data_end_access(const struct bpf_insn * si,struct bpf_insn * insn)9735 static struct bpf_insn *bpf_convert_data_end_access(const struct bpf_insn *si,
9736 struct bpf_insn *insn)
9737 {
9738 /* si->dst_reg = skb->data */
9739 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
9740 si->dst_reg, si->src_reg,
9741 offsetof(struct sk_buff, data));
9742 /* AX = skb->len */
9743 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, len),
9744 BPF_REG_AX, si->src_reg,
9745 offsetof(struct sk_buff, len));
9746 /* si->dst_reg = skb->data + skb->len */
9747 *insn++ = BPF_ALU64_REG(BPF_ADD, si->dst_reg, BPF_REG_AX);
9748 /* AX = skb->data_len */
9749 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data_len),
9750 BPF_REG_AX, si->src_reg,
9751 offsetof(struct sk_buff, data_len));
9752 /* si->dst_reg = skb->data + skb->len - skb->data_len */
9753 *insn++ = BPF_ALU64_REG(BPF_SUB, si->dst_reg, BPF_REG_AX);
9754
9755 return insn;
9756 }
9757
sk_skb_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)9758 static u32 sk_skb_convert_ctx_access(enum bpf_access_type type,
9759 const struct bpf_insn *si,
9760 struct bpf_insn *insn_buf,
9761 struct bpf_prog *prog, u32 *target_size)
9762 {
9763 struct bpf_insn *insn = insn_buf;
9764
9765 switch (si->off) {
9766 case offsetof(struct __sk_buff, data_end):
9767 insn = bpf_convert_data_end_access(si, insn);
9768 break;
9769 default:
9770 return bpf_convert_ctx_access(type, si, insn_buf, prog,
9771 target_size);
9772 }
9773
9774 return insn - insn_buf;
9775 }
9776
sk_msg_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)9777 static u32 sk_msg_convert_ctx_access(enum bpf_access_type type,
9778 const struct bpf_insn *si,
9779 struct bpf_insn *insn_buf,
9780 struct bpf_prog *prog, u32 *target_size)
9781 {
9782 struct bpf_insn *insn = insn_buf;
9783 #if IS_ENABLED(CONFIG_IPV6)
9784 int off;
9785 #endif
9786
9787 /* convert ctx uses the fact sg element is first in struct */
9788 BUILD_BUG_ON(offsetof(struct sk_msg, sg) != 0);
9789
9790 switch (si->off) {
9791 case offsetof(struct sk_msg_md, data):
9792 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg, data),
9793 si->dst_reg, si->src_reg,
9794 offsetof(struct sk_msg, data));
9795 break;
9796 case offsetof(struct sk_msg_md, data_end):
9797 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg, data_end),
9798 si->dst_reg, si->src_reg,
9799 offsetof(struct sk_msg, data_end));
9800 break;
9801 case offsetof(struct sk_msg_md, family):
9802 BUILD_BUG_ON(sizeof_field(struct sock_common, skc_family) != 2);
9803
9804 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
9805 struct sk_msg, sk),
9806 si->dst_reg, si->src_reg,
9807 offsetof(struct sk_msg, sk));
9808 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
9809 offsetof(struct sock_common, skc_family));
9810 break;
9811
9812 case offsetof(struct sk_msg_md, remote_ip4):
9813 BUILD_BUG_ON(sizeof_field(struct sock_common, skc_daddr) != 4);
9814
9815 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
9816 struct sk_msg, sk),
9817 si->dst_reg, si->src_reg,
9818 offsetof(struct sk_msg, sk));
9819 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9820 offsetof(struct sock_common, skc_daddr));
9821 break;
9822
9823 case offsetof(struct sk_msg_md, local_ip4):
9824 BUILD_BUG_ON(sizeof_field(struct sock_common,
9825 skc_rcv_saddr) != 4);
9826
9827 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
9828 struct sk_msg, sk),
9829 si->dst_reg, si->src_reg,
9830 offsetof(struct sk_msg, sk));
9831 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9832 offsetof(struct sock_common,
9833 skc_rcv_saddr));
9834 break;
9835
9836 case offsetof(struct sk_msg_md, remote_ip6[0]) ...
9837 offsetof(struct sk_msg_md, remote_ip6[3]):
9838 #if IS_ENABLED(CONFIG_IPV6)
9839 BUILD_BUG_ON(sizeof_field(struct sock_common,
9840 skc_v6_daddr.s6_addr32[0]) != 4);
9841
9842 off = si->off;
9843 off -= offsetof(struct sk_msg_md, remote_ip6[0]);
9844 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
9845 struct sk_msg, sk),
9846 si->dst_reg, si->src_reg,
9847 offsetof(struct sk_msg, sk));
9848 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9849 offsetof(struct sock_common,
9850 skc_v6_daddr.s6_addr32[0]) +
9851 off);
9852 #else
9853 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
9854 #endif
9855 break;
9856
9857 case offsetof(struct sk_msg_md, local_ip6[0]) ...
9858 offsetof(struct sk_msg_md, local_ip6[3]):
9859 #if IS_ENABLED(CONFIG_IPV6)
9860 BUILD_BUG_ON(sizeof_field(struct sock_common,
9861 skc_v6_rcv_saddr.s6_addr32[0]) != 4);
9862
9863 off = si->off;
9864 off -= offsetof(struct sk_msg_md, local_ip6[0]);
9865 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
9866 struct sk_msg, sk),
9867 si->dst_reg, si->src_reg,
9868 offsetof(struct sk_msg, sk));
9869 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9870 offsetof(struct sock_common,
9871 skc_v6_rcv_saddr.s6_addr32[0]) +
9872 off);
9873 #else
9874 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
9875 #endif
9876 break;
9877
9878 case offsetof(struct sk_msg_md, remote_port):
9879 BUILD_BUG_ON(sizeof_field(struct sock_common, skc_dport) != 2);
9880
9881 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
9882 struct sk_msg, sk),
9883 si->dst_reg, si->src_reg,
9884 offsetof(struct sk_msg, sk));
9885 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
9886 offsetof(struct sock_common, skc_dport));
9887 #ifndef __BIG_ENDIAN_BITFIELD
9888 *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
9889 #endif
9890 break;
9891
9892 case offsetof(struct sk_msg_md, local_port):
9893 BUILD_BUG_ON(sizeof_field(struct sock_common, skc_num) != 2);
9894
9895 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
9896 struct sk_msg, sk),
9897 si->dst_reg, si->src_reg,
9898 offsetof(struct sk_msg, sk));
9899 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
9900 offsetof(struct sock_common, skc_num));
9901 break;
9902
9903 case offsetof(struct sk_msg_md, size):
9904 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg_sg, size),
9905 si->dst_reg, si->src_reg,
9906 offsetof(struct sk_msg_sg, size));
9907 break;
9908
9909 case offsetof(struct sk_msg_md, sk):
9910 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg, sk),
9911 si->dst_reg, si->src_reg,
9912 offsetof(struct sk_msg, sk));
9913 break;
9914 }
9915
9916 return insn - insn_buf;
9917 }
9918
9919 const struct bpf_verifier_ops sk_filter_verifier_ops = {
9920 .get_func_proto = sk_filter_func_proto,
9921 .is_valid_access = sk_filter_is_valid_access,
9922 .convert_ctx_access = bpf_convert_ctx_access,
9923 .gen_ld_abs = bpf_gen_ld_abs,
9924 };
9925
9926 const struct bpf_prog_ops sk_filter_prog_ops = {
9927 .test_run = bpf_prog_test_run_skb,
9928 };
9929
9930 const struct bpf_verifier_ops tc_cls_act_verifier_ops = {
9931 .get_func_proto = tc_cls_act_func_proto,
9932 .is_valid_access = tc_cls_act_is_valid_access,
9933 .convert_ctx_access = tc_cls_act_convert_ctx_access,
9934 .gen_prologue = tc_cls_act_prologue,
9935 .gen_ld_abs = bpf_gen_ld_abs,
9936 .check_kfunc_call = bpf_prog_test_check_kfunc_call,
9937 };
9938
9939 const struct bpf_prog_ops tc_cls_act_prog_ops = {
9940 .test_run = bpf_prog_test_run_skb,
9941 };
9942
9943 const struct bpf_verifier_ops xdp_verifier_ops = {
9944 .get_func_proto = xdp_func_proto,
9945 .is_valid_access = xdp_is_valid_access,
9946 .convert_ctx_access = xdp_convert_ctx_access,
9947 .gen_prologue = bpf_noop_prologue,
9948 };
9949
9950 const struct bpf_prog_ops xdp_prog_ops = {
9951 .test_run = bpf_prog_test_run_xdp,
9952 };
9953
9954 const struct bpf_verifier_ops cg_skb_verifier_ops = {
9955 .get_func_proto = cg_skb_func_proto,
9956 .is_valid_access = cg_skb_is_valid_access,
9957 .convert_ctx_access = bpf_convert_ctx_access,
9958 };
9959
9960 const struct bpf_prog_ops cg_skb_prog_ops = {
9961 .test_run = bpf_prog_test_run_skb,
9962 };
9963
9964 const struct bpf_verifier_ops lwt_in_verifier_ops = {
9965 .get_func_proto = lwt_in_func_proto,
9966 .is_valid_access = lwt_is_valid_access,
9967 .convert_ctx_access = bpf_convert_ctx_access,
9968 };
9969
9970 const struct bpf_prog_ops lwt_in_prog_ops = {
9971 .test_run = bpf_prog_test_run_skb,
9972 };
9973
9974 const struct bpf_verifier_ops lwt_out_verifier_ops = {
9975 .get_func_proto = lwt_out_func_proto,
9976 .is_valid_access = lwt_is_valid_access,
9977 .convert_ctx_access = bpf_convert_ctx_access,
9978 };
9979
9980 const struct bpf_prog_ops lwt_out_prog_ops = {
9981 .test_run = bpf_prog_test_run_skb,
9982 };
9983
9984 const struct bpf_verifier_ops lwt_xmit_verifier_ops = {
9985 .get_func_proto = lwt_xmit_func_proto,
9986 .is_valid_access = lwt_is_valid_access,
9987 .convert_ctx_access = bpf_convert_ctx_access,
9988 .gen_prologue = tc_cls_act_prologue,
9989 };
9990
9991 const struct bpf_prog_ops lwt_xmit_prog_ops = {
9992 .test_run = bpf_prog_test_run_skb,
9993 };
9994
9995 const struct bpf_verifier_ops lwt_seg6local_verifier_ops = {
9996 .get_func_proto = lwt_seg6local_func_proto,
9997 .is_valid_access = lwt_is_valid_access,
9998 .convert_ctx_access = bpf_convert_ctx_access,
9999 };
10000
10001 const struct bpf_prog_ops lwt_seg6local_prog_ops = {
10002 .test_run = bpf_prog_test_run_skb,
10003 };
10004
10005 const struct bpf_verifier_ops cg_sock_verifier_ops = {
10006 .get_func_proto = sock_filter_func_proto,
10007 .is_valid_access = sock_filter_is_valid_access,
10008 .convert_ctx_access = bpf_sock_convert_ctx_access,
10009 };
10010
10011 const struct bpf_prog_ops cg_sock_prog_ops = {
10012 };
10013
10014 const struct bpf_verifier_ops cg_sock_addr_verifier_ops = {
10015 .get_func_proto = sock_addr_func_proto,
10016 .is_valid_access = sock_addr_is_valid_access,
10017 .convert_ctx_access = sock_addr_convert_ctx_access,
10018 };
10019
10020 const struct bpf_prog_ops cg_sock_addr_prog_ops = {
10021 };
10022
10023 const struct bpf_verifier_ops sock_ops_verifier_ops = {
10024 .get_func_proto = sock_ops_func_proto,
10025 .is_valid_access = sock_ops_is_valid_access,
10026 .convert_ctx_access = sock_ops_convert_ctx_access,
10027 };
10028
10029 const struct bpf_prog_ops sock_ops_prog_ops = {
10030 };
10031
10032 const struct bpf_verifier_ops sk_skb_verifier_ops = {
10033 .get_func_proto = sk_skb_func_proto,
10034 .is_valid_access = sk_skb_is_valid_access,
10035 .convert_ctx_access = sk_skb_convert_ctx_access,
10036 .gen_prologue = sk_skb_prologue,
10037 };
10038
10039 const struct bpf_prog_ops sk_skb_prog_ops = {
10040 };
10041
10042 const struct bpf_verifier_ops sk_msg_verifier_ops = {
10043 .get_func_proto = sk_msg_func_proto,
10044 .is_valid_access = sk_msg_is_valid_access,
10045 .convert_ctx_access = sk_msg_convert_ctx_access,
10046 .gen_prologue = bpf_noop_prologue,
10047 };
10048
10049 const struct bpf_prog_ops sk_msg_prog_ops = {
10050 };
10051
10052 const struct bpf_verifier_ops flow_dissector_verifier_ops = {
10053 .get_func_proto = flow_dissector_func_proto,
10054 .is_valid_access = flow_dissector_is_valid_access,
10055 .convert_ctx_access = flow_dissector_convert_ctx_access,
10056 };
10057
10058 const struct bpf_prog_ops flow_dissector_prog_ops = {
10059 .test_run = bpf_prog_test_run_flow_dissector,
10060 };
10061
sk_detach_filter(struct sock * sk)10062 int sk_detach_filter(struct sock *sk)
10063 {
10064 int ret = -ENOENT;
10065 struct sk_filter *filter;
10066
10067 if (sock_flag(sk, SOCK_FILTER_LOCKED))
10068 return -EPERM;
10069
10070 filter = rcu_dereference_protected(sk->sk_filter,
10071 lockdep_sock_is_held(sk));
10072 if (filter) {
10073 RCU_INIT_POINTER(sk->sk_filter, NULL);
10074 sk_filter_uncharge(sk, filter);
10075 ret = 0;
10076 }
10077
10078 return ret;
10079 }
10080 EXPORT_SYMBOL_GPL(sk_detach_filter);
10081
sk_get_filter(struct sock * sk,struct sock_filter __user * ubuf,unsigned int len)10082 int sk_get_filter(struct sock *sk, struct sock_filter __user *ubuf,
10083 unsigned int len)
10084 {
10085 struct sock_fprog_kern *fprog;
10086 struct sk_filter *filter;
10087 int ret = 0;
10088
10089 lock_sock(sk);
10090 filter = rcu_dereference_protected(sk->sk_filter,
10091 lockdep_sock_is_held(sk));
10092 if (!filter)
10093 goto out;
10094
10095 /* We're copying the filter that has been originally attached,
10096 * so no conversion/decode needed anymore. eBPF programs that
10097 * have no original program cannot be dumped through this.
10098 */
10099 ret = -EACCES;
10100 fprog = filter->prog->orig_prog;
10101 if (!fprog)
10102 goto out;
10103
10104 ret = fprog->len;
10105 if (!len)
10106 /* User space only enquires number of filter blocks. */
10107 goto out;
10108
10109 ret = -EINVAL;
10110 if (len < fprog->len)
10111 goto out;
10112
10113 ret = -EFAULT;
10114 if (copy_to_user(ubuf, fprog->filter, bpf_classic_proglen(fprog)))
10115 goto out;
10116
10117 /* Instead of bytes, the API requests to return the number
10118 * of filter blocks.
10119 */
10120 ret = fprog->len;
10121 out:
10122 release_sock(sk);
10123 return ret;
10124 }
10125
10126 #ifdef CONFIG_INET
bpf_init_reuseport_kern(struct sk_reuseport_kern * reuse_kern,struct sock_reuseport * reuse,struct sock * sk,struct sk_buff * skb,struct sock * migrating_sk,u32 hash)10127 static void bpf_init_reuseport_kern(struct sk_reuseport_kern *reuse_kern,
10128 struct sock_reuseport *reuse,
10129 struct sock *sk, struct sk_buff *skb,
10130 struct sock *migrating_sk,
10131 u32 hash)
10132 {
10133 reuse_kern->skb = skb;
10134 reuse_kern->sk = sk;
10135 reuse_kern->selected_sk = NULL;
10136 reuse_kern->migrating_sk = migrating_sk;
10137 reuse_kern->data_end = skb->data + skb_headlen(skb);
10138 reuse_kern->hash = hash;
10139 reuse_kern->reuseport_id = reuse->reuseport_id;
10140 reuse_kern->bind_inany = reuse->bind_inany;
10141 }
10142
bpf_run_sk_reuseport(struct sock_reuseport * reuse,struct sock * sk,struct bpf_prog * prog,struct sk_buff * skb,struct sock * migrating_sk,u32 hash)10143 struct sock *bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
10144 struct bpf_prog *prog, struct sk_buff *skb,
10145 struct sock *migrating_sk,
10146 u32 hash)
10147 {
10148 struct sk_reuseport_kern reuse_kern;
10149 enum sk_action action;
10150
10151 bpf_init_reuseport_kern(&reuse_kern, reuse, sk, skb, migrating_sk, hash);
10152 action = bpf_prog_run(prog, &reuse_kern);
10153
10154 if (action == SK_PASS)
10155 return reuse_kern.selected_sk;
10156 else
10157 return ERR_PTR(-ECONNREFUSED);
10158 }
10159
BPF_CALL_4(sk_select_reuseport,struct sk_reuseport_kern *,reuse_kern,struct bpf_map *,map,void *,key,u32,flags)10160 BPF_CALL_4(sk_select_reuseport, struct sk_reuseport_kern *, reuse_kern,
10161 struct bpf_map *, map, void *, key, u32, flags)
10162 {
10163 bool is_sockarray = map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY;
10164 struct sock_reuseport *reuse;
10165 struct sock *selected_sk;
10166
10167 selected_sk = map->ops->map_lookup_elem(map, key);
10168 if (!selected_sk)
10169 return -ENOENT;
10170
10171 reuse = rcu_dereference(selected_sk->sk_reuseport_cb);
10172 if (!reuse) {
10173 /* Lookup in sock_map can return TCP ESTABLISHED sockets. */
10174 if (sk_is_refcounted(selected_sk))
10175 sock_put(selected_sk);
10176
10177 /* reuseport_array has only sk with non NULL sk_reuseport_cb.
10178 * The only (!reuse) case here is - the sk has already been
10179 * unhashed (e.g. by close()), so treat it as -ENOENT.
10180 *
10181 * Other maps (e.g. sock_map) do not provide this guarantee and
10182 * the sk may never be in the reuseport group to begin with.
10183 */
10184 return is_sockarray ? -ENOENT : -EINVAL;
10185 }
10186
10187 if (unlikely(reuse->reuseport_id != reuse_kern->reuseport_id)) {
10188 struct sock *sk = reuse_kern->sk;
10189
10190 if (sk->sk_protocol != selected_sk->sk_protocol)
10191 return -EPROTOTYPE;
10192 else if (sk->sk_family != selected_sk->sk_family)
10193 return -EAFNOSUPPORT;
10194
10195 /* Catch all. Likely bound to a different sockaddr. */
10196 return -EBADFD;
10197 }
10198
10199 reuse_kern->selected_sk = selected_sk;
10200
10201 return 0;
10202 }
10203
10204 static const struct bpf_func_proto sk_select_reuseport_proto = {
10205 .func = sk_select_reuseport,
10206 .gpl_only = false,
10207 .ret_type = RET_INTEGER,
10208 .arg1_type = ARG_PTR_TO_CTX,
10209 .arg2_type = ARG_CONST_MAP_PTR,
10210 .arg3_type = ARG_PTR_TO_MAP_KEY,
10211 .arg4_type = ARG_ANYTHING,
10212 };
10213
BPF_CALL_4(sk_reuseport_load_bytes,const struct sk_reuseport_kern *,reuse_kern,u32,offset,void *,to,u32,len)10214 BPF_CALL_4(sk_reuseport_load_bytes,
10215 const struct sk_reuseport_kern *, reuse_kern, u32, offset,
10216 void *, to, u32, len)
10217 {
10218 return ____bpf_skb_load_bytes(reuse_kern->skb, offset, to, len);
10219 }
10220
10221 static const struct bpf_func_proto sk_reuseport_load_bytes_proto = {
10222 .func = sk_reuseport_load_bytes,
10223 .gpl_only = false,
10224 .ret_type = RET_INTEGER,
10225 .arg1_type = ARG_PTR_TO_CTX,
10226 .arg2_type = ARG_ANYTHING,
10227 .arg3_type = ARG_PTR_TO_UNINIT_MEM,
10228 .arg4_type = ARG_CONST_SIZE,
10229 };
10230
BPF_CALL_5(sk_reuseport_load_bytes_relative,const struct sk_reuseport_kern *,reuse_kern,u32,offset,void *,to,u32,len,u32,start_header)10231 BPF_CALL_5(sk_reuseport_load_bytes_relative,
10232 const struct sk_reuseport_kern *, reuse_kern, u32, offset,
10233 void *, to, u32, len, u32, start_header)
10234 {
10235 return ____bpf_skb_load_bytes_relative(reuse_kern->skb, offset, to,
10236 len, start_header);
10237 }
10238
10239 static const struct bpf_func_proto sk_reuseport_load_bytes_relative_proto = {
10240 .func = sk_reuseport_load_bytes_relative,
10241 .gpl_only = false,
10242 .ret_type = RET_INTEGER,
10243 .arg1_type = ARG_PTR_TO_CTX,
10244 .arg2_type = ARG_ANYTHING,
10245 .arg3_type = ARG_PTR_TO_UNINIT_MEM,
10246 .arg4_type = ARG_CONST_SIZE,
10247 .arg5_type = ARG_ANYTHING,
10248 };
10249
10250 static const struct bpf_func_proto *
sk_reuseport_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)10251 sk_reuseport_func_proto(enum bpf_func_id func_id,
10252 const struct bpf_prog *prog)
10253 {
10254 switch (func_id) {
10255 case BPF_FUNC_sk_select_reuseport:
10256 return &sk_select_reuseport_proto;
10257 case BPF_FUNC_skb_load_bytes:
10258 return &sk_reuseport_load_bytes_proto;
10259 case BPF_FUNC_skb_load_bytes_relative:
10260 return &sk_reuseport_load_bytes_relative_proto;
10261 case BPF_FUNC_get_socket_cookie:
10262 return &bpf_get_socket_ptr_cookie_proto;
10263 default:
10264 return bpf_base_func_proto(func_id);
10265 }
10266 }
10267
10268 static bool
sk_reuseport_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)10269 sk_reuseport_is_valid_access(int off, int size,
10270 enum bpf_access_type type,
10271 const struct bpf_prog *prog,
10272 struct bpf_insn_access_aux *info)
10273 {
10274 const u32 size_default = sizeof(__u32);
10275
10276 if (off < 0 || off >= sizeof(struct sk_reuseport_md) ||
10277 off % size || type != BPF_READ)
10278 return false;
10279
10280 switch (off) {
10281 case offsetof(struct sk_reuseport_md, data):
10282 info->reg_type = PTR_TO_PACKET;
10283 return size == sizeof(__u64);
10284
10285 case offsetof(struct sk_reuseport_md, data_end):
10286 info->reg_type = PTR_TO_PACKET_END;
10287 return size == sizeof(__u64);
10288
10289 case offsetof(struct sk_reuseport_md, hash):
10290 return size == size_default;
10291
10292 case offsetof(struct sk_reuseport_md, sk):
10293 info->reg_type = PTR_TO_SOCKET;
10294 return size == sizeof(__u64);
10295
10296 case offsetof(struct sk_reuseport_md, migrating_sk):
10297 info->reg_type = PTR_TO_SOCK_COMMON_OR_NULL;
10298 return size == sizeof(__u64);
10299
10300 /* Fields that allow narrowing */
10301 case bpf_ctx_range(struct sk_reuseport_md, eth_protocol):
10302 if (size < sizeof_field(struct sk_buff, protocol))
10303 return false;
10304 fallthrough;
10305 case bpf_ctx_range(struct sk_reuseport_md, ip_protocol):
10306 case bpf_ctx_range(struct sk_reuseport_md, bind_inany):
10307 case bpf_ctx_range(struct sk_reuseport_md, len):
10308 bpf_ctx_record_field_size(info, size_default);
10309 return bpf_ctx_narrow_access_ok(off, size, size_default);
10310
10311 default:
10312 return false;
10313 }
10314 }
10315
10316 #define SK_REUSEPORT_LOAD_FIELD(F) ({ \
10317 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_reuseport_kern, F), \
10318 si->dst_reg, si->src_reg, \
10319 bpf_target_off(struct sk_reuseport_kern, F, \
10320 sizeof_field(struct sk_reuseport_kern, F), \
10321 target_size)); \
10322 })
10323
10324 #define SK_REUSEPORT_LOAD_SKB_FIELD(SKB_FIELD) \
10325 SOCK_ADDR_LOAD_NESTED_FIELD(struct sk_reuseport_kern, \
10326 struct sk_buff, \
10327 skb, \
10328 SKB_FIELD)
10329
10330 #define SK_REUSEPORT_LOAD_SK_FIELD(SK_FIELD) \
10331 SOCK_ADDR_LOAD_NESTED_FIELD(struct sk_reuseport_kern, \
10332 struct sock, \
10333 sk, \
10334 SK_FIELD)
10335
sk_reuseport_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)10336 static u32 sk_reuseport_convert_ctx_access(enum bpf_access_type type,
10337 const struct bpf_insn *si,
10338 struct bpf_insn *insn_buf,
10339 struct bpf_prog *prog,
10340 u32 *target_size)
10341 {
10342 struct bpf_insn *insn = insn_buf;
10343
10344 switch (si->off) {
10345 case offsetof(struct sk_reuseport_md, data):
10346 SK_REUSEPORT_LOAD_SKB_FIELD(data);
10347 break;
10348
10349 case offsetof(struct sk_reuseport_md, len):
10350 SK_REUSEPORT_LOAD_SKB_FIELD(len);
10351 break;
10352
10353 case offsetof(struct sk_reuseport_md, eth_protocol):
10354 SK_REUSEPORT_LOAD_SKB_FIELD(protocol);
10355 break;
10356
10357 case offsetof(struct sk_reuseport_md, ip_protocol):
10358 SK_REUSEPORT_LOAD_SK_FIELD(sk_protocol);
10359 break;
10360
10361 case offsetof(struct sk_reuseport_md, data_end):
10362 SK_REUSEPORT_LOAD_FIELD(data_end);
10363 break;
10364
10365 case offsetof(struct sk_reuseport_md, hash):
10366 SK_REUSEPORT_LOAD_FIELD(hash);
10367 break;
10368
10369 case offsetof(struct sk_reuseport_md, bind_inany):
10370 SK_REUSEPORT_LOAD_FIELD(bind_inany);
10371 break;
10372
10373 case offsetof(struct sk_reuseport_md, sk):
10374 SK_REUSEPORT_LOAD_FIELD(sk);
10375 break;
10376
10377 case offsetof(struct sk_reuseport_md, migrating_sk):
10378 SK_REUSEPORT_LOAD_FIELD(migrating_sk);
10379 break;
10380 }
10381
10382 return insn - insn_buf;
10383 }
10384
10385 const struct bpf_verifier_ops sk_reuseport_verifier_ops = {
10386 .get_func_proto = sk_reuseport_func_proto,
10387 .is_valid_access = sk_reuseport_is_valid_access,
10388 .convert_ctx_access = sk_reuseport_convert_ctx_access,
10389 };
10390
10391 const struct bpf_prog_ops sk_reuseport_prog_ops = {
10392 };
10393
10394 DEFINE_STATIC_KEY_FALSE(bpf_sk_lookup_enabled);
10395 EXPORT_SYMBOL(bpf_sk_lookup_enabled);
10396
BPF_CALL_3(bpf_sk_lookup_assign,struct bpf_sk_lookup_kern *,ctx,struct sock *,sk,u64,flags)10397 BPF_CALL_3(bpf_sk_lookup_assign, struct bpf_sk_lookup_kern *, ctx,
10398 struct sock *, sk, u64, flags)
10399 {
10400 if (unlikely(flags & ~(BPF_SK_LOOKUP_F_REPLACE |
10401 BPF_SK_LOOKUP_F_NO_REUSEPORT)))
10402 return -EINVAL;
10403 if (unlikely(sk && sk_is_refcounted(sk)))
10404 return -ESOCKTNOSUPPORT; /* reject non-RCU freed sockets */
10405 if (unlikely(sk && sk->sk_state == TCP_ESTABLISHED))
10406 return -ESOCKTNOSUPPORT; /* reject connected sockets */
10407
10408 /* Check if socket is suitable for packet L3/L4 protocol */
10409 if (sk && sk->sk_protocol != ctx->protocol)
10410 return -EPROTOTYPE;
10411 if (sk && sk->sk_family != ctx->family &&
10412 (sk->sk_family == AF_INET || ipv6_only_sock(sk)))
10413 return -EAFNOSUPPORT;
10414
10415 if (ctx->selected_sk && !(flags & BPF_SK_LOOKUP_F_REPLACE))
10416 return -EEXIST;
10417
10418 /* Select socket as lookup result */
10419 ctx->selected_sk = sk;
10420 ctx->no_reuseport = flags & BPF_SK_LOOKUP_F_NO_REUSEPORT;
10421 return 0;
10422 }
10423
10424 static const struct bpf_func_proto bpf_sk_lookup_assign_proto = {
10425 .func = bpf_sk_lookup_assign,
10426 .gpl_only = false,
10427 .ret_type = RET_INTEGER,
10428 .arg1_type = ARG_PTR_TO_CTX,
10429 .arg2_type = ARG_PTR_TO_SOCKET_OR_NULL,
10430 .arg3_type = ARG_ANYTHING,
10431 };
10432
10433 static const struct bpf_func_proto *
sk_lookup_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)10434 sk_lookup_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
10435 {
10436 switch (func_id) {
10437 case BPF_FUNC_perf_event_output:
10438 return &bpf_event_output_data_proto;
10439 case BPF_FUNC_sk_assign:
10440 return &bpf_sk_lookup_assign_proto;
10441 case BPF_FUNC_sk_release:
10442 return &bpf_sk_release_proto;
10443 default:
10444 return bpf_sk_base_func_proto(func_id);
10445 }
10446 }
10447
sk_lookup_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)10448 static bool sk_lookup_is_valid_access(int off, int size,
10449 enum bpf_access_type type,
10450 const struct bpf_prog *prog,
10451 struct bpf_insn_access_aux *info)
10452 {
10453 if (off < 0 || off >= sizeof(struct bpf_sk_lookup))
10454 return false;
10455 if (off % size != 0)
10456 return false;
10457 if (type != BPF_READ)
10458 return false;
10459
10460 switch (off) {
10461 case offsetof(struct bpf_sk_lookup, sk):
10462 info->reg_type = PTR_TO_SOCKET_OR_NULL;
10463 return size == sizeof(__u64);
10464
10465 case bpf_ctx_range(struct bpf_sk_lookup, family):
10466 case bpf_ctx_range(struct bpf_sk_lookup, protocol):
10467 case bpf_ctx_range(struct bpf_sk_lookup, remote_ip4):
10468 case bpf_ctx_range(struct bpf_sk_lookup, local_ip4):
10469 case bpf_ctx_range_till(struct bpf_sk_lookup, remote_ip6[0], remote_ip6[3]):
10470 case bpf_ctx_range_till(struct bpf_sk_lookup, local_ip6[0], local_ip6[3]):
10471 case bpf_ctx_range(struct bpf_sk_lookup, remote_port):
10472 case bpf_ctx_range(struct bpf_sk_lookup, local_port):
10473 bpf_ctx_record_field_size(info, sizeof(__u32));
10474 return bpf_ctx_narrow_access_ok(off, size, sizeof(__u32));
10475
10476 default:
10477 return false;
10478 }
10479 }
10480
sk_lookup_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)10481 static u32 sk_lookup_convert_ctx_access(enum bpf_access_type type,
10482 const struct bpf_insn *si,
10483 struct bpf_insn *insn_buf,
10484 struct bpf_prog *prog,
10485 u32 *target_size)
10486 {
10487 struct bpf_insn *insn = insn_buf;
10488
10489 switch (si->off) {
10490 case offsetof(struct bpf_sk_lookup, sk):
10491 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg, si->src_reg,
10492 offsetof(struct bpf_sk_lookup_kern, selected_sk));
10493 break;
10494
10495 case offsetof(struct bpf_sk_lookup, family):
10496 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
10497 bpf_target_off(struct bpf_sk_lookup_kern,
10498 family, 2, target_size));
10499 break;
10500
10501 case offsetof(struct bpf_sk_lookup, protocol):
10502 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
10503 bpf_target_off(struct bpf_sk_lookup_kern,
10504 protocol, 2, target_size));
10505 break;
10506
10507 case offsetof(struct bpf_sk_lookup, remote_ip4):
10508 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
10509 bpf_target_off(struct bpf_sk_lookup_kern,
10510 v4.saddr, 4, target_size));
10511 break;
10512
10513 case offsetof(struct bpf_sk_lookup, local_ip4):
10514 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
10515 bpf_target_off(struct bpf_sk_lookup_kern,
10516 v4.daddr, 4, target_size));
10517 break;
10518
10519 case bpf_ctx_range_till(struct bpf_sk_lookup,
10520 remote_ip6[0], remote_ip6[3]): {
10521 #if IS_ENABLED(CONFIG_IPV6)
10522 int off = si->off;
10523
10524 off -= offsetof(struct bpf_sk_lookup, remote_ip6[0]);
10525 off += bpf_target_off(struct in6_addr, s6_addr32[0], 4, target_size);
10526 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg, si->src_reg,
10527 offsetof(struct bpf_sk_lookup_kern, v6.saddr));
10528 *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
10529 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, off);
10530 #else
10531 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
10532 #endif
10533 break;
10534 }
10535 case bpf_ctx_range_till(struct bpf_sk_lookup,
10536 local_ip6[0], local_ip6[3]): {
10537 #if IS_ENABLED(CONFIG_IPV6)
10538 int off = si->off;
10539
10540 off -= offsetof(struct bpf_sk_lookup, local_ip6[0]);
10541 off += bpf_target_off(struct in6_addr, s6_addr32[0], 4, target_size);
10542 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg, si->src_reg,
10543 offsetof(struct bpf_sk_lookup_kern, v6.daddr));
10544 *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
10545 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, off);
10546 #else
10547 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
10548 #endif
10549 break;
10550 }
10551 case offsetof(struct bpf_sk_lookup, remote_port):
10552 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
10553 bpf_target_off(struct bpf_sk_lookup_kern,
10554 sport, 2, target_size));
10555 break;
10556
10557 case offsetof(struct bpf_sk_lookup, local_port):
10558 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
10559 bpf_target_off(struct bpf_sk_lookup_kern,
10560 dport, 2, target_size));
10561 break;
10562 }
10563
10564 return insn - insn_buf;
10565 }
10566
10567 const struct bpf_prog_ops sk_lookup_prog_ops = {
10568 .test_run = bpf_prog_test_run_sk_lookup,
10569 };
10570
10571 const struct bpf_verifier_ops sk_lookup_verifier_ops = {
10572 .get_func_proto = sk_lookup_func_proto,
10573 .is_valid_access = sk_lookup_is_valid_access,
10574 .convert_ctx_access = sk_lookup_convert_ctx_access,
10575 };
10576
10577 #endif /* CONFIG_INET */
10578
DEFINE_BPF_DISPATCHER(xdp)10579 DEFINE_BPF_DISPATCHER(xdp)
10580
10581 void bpf_prog_change_xdp(struct bpf_prog *prev_prog, struct bpf_prog *prog)
10582 {
10583 bpf_dispatcher_change_prog(BPF_DISPATCHER_PTR(xdp), prev_prog, prog);
10584 }
10585
10586 #ifdef CONFIG_DEBUG_INFO_BTF
BTF_ID_LIST_GLOBAL(btf_sock_ids)10587 BTF_ID_LIST_GLOBAL(btf_sock_ids)
10588 #define BTF_SOCK_TYPE(name, type) BTF_ID(struct, type)
10589 BTF_SOCK_TYPE_xxx
10590 #undef BTF_SOCK_TYPE
10591 #else
10592 u32 btf_sock_ids[MAX_BTF_SOCK_TYPE];
10593 #endif
10594
10595 BPF_CALL_1(bpf_skc_to_tcp6_sock, struct sock *, sk)
10596 {
10597 /* tcp6_sock type is not generated in dwarf and hence btf,
10598 * trigger an explicit type generation here.
10599 */
10600 BTF_TYPE_EMIT(struct tcp6_sock);
10601 if (sk && sk_fullsock(sk) && sk->sk_protocol == IPPROTO_TCP &&
10602 sk->sk_family == AF_INET6)
10603 return (unsigned long)sk;
10604
10605 return (unsigned long)NULL;
10606 }
10607
10608 const struct bpf_func_proto bpf_skc_to_tcp6_sock_proto = {
10609 .func = bpf_skc_to_tcp6_sock,
10610 .gpl_only = false,
10611 .ret_type = RET_PTR_TO_BTF_ID_OR_NULL,
10612 .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
10613 .ret_btf_id = &btf_sock_ids[BTF_SOCK_TYPE_TCP6],
10614 };
10615
BPF_CALL_1(bpf_skc_to_tcp_sock,struct sock *,sk)10616 BPF_CALL_1(bpf_skc_to_tcp_sock, struct sock *, sk)
10617 {
10618 if (sk && sk_fullsock(sk) && sk->sk_protocol == IPPROTO_TCP)
10619 return (unsigned long)sk;
10620
10621 return (unsigned long)NULL;
10622 }
10623
10624 const struct bpf_func_proto bpf_skc_to_tcp_sock_proto = {
10625 .func = bpf_skc_to_tcp_sock,
10626 .gpl_only = false,
10627 .ret_type = RET_PTR_TO_BTF_ID_OR_NULL,
10628 .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
10629 .ret_btf_id = &btf_sock_ids[BTF_SOCK_TYPE_TCP],
10630 };
10631
BPF_CALL_1(bpf_skc_to_tcp_timewait_sock,struct sock *,sk)10632 BPF_CALL_1(bpf_skc_to_tcp_timewait_sock, struct sock *, sk)
10633 {
10634 /* BTF types for tcp_timewait_sock and inet_timewait_sock are not
10635 * generated if CONFIG_INET=n. Trigger an explicit generation here.
10636 */
10637 BTF_TYPE_EMIT(struct inet_timewait_sock);
10638 BTF_TYPE_EMIT(struct tcp_timewait_sock);
10639
10640 #ifdef CONFIG_INET
10641 if (sk && sk->sk_prot == &tcp_prot && sk->sk_state == TCP_TIME_WAIT)
10642 return (unsigned long)sk;
10643 #endif
10644
10645 #if IS_BUILTIN(CONFIG_IPV6)
10646 if (sk && sk->sk_prot == &tcpv6_prot && sk->sk_state == TCP_TIME_WAIT)
10647 return (unsigned long)sk;
10648 #endif
10649
10650 return (unsigned long)NULL;
10651 }
10652
10653 const struct bpf_func_proto bpf_skc_to_tcp_timewait_sock_proto = {
10654 .func = bpf_skc_to_tcp_timewait_sock,
10655 .gpl_only = false,
10656 .ret_type = RET_PTR_TO_BTF_ID_OR_NULL,
10657 .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
10658 .ret_btf_id = &btf_sock_ids[BTF_SOCK_TYPE_TCP_TW],
10659 };
10660
BPF_CALL_1(bpf_skc_to_tcp_request_sock,struct sock *,sk)10661 BPF_CALL_1(bpf_skc_to_tcp_request_sock, struct sock *, sk)
10662 {
10663 #ifdef CONFIG_INET
10664 if (sk && sk->sk_prot == &tcp_prot && sk->sk_state == TCP_NEW_SYN_RECV)
10665 return (unsigned long)sk;
10666 #endif
10667
10668 #if IS_BUILTIN(CONFIG_IPV6)
10669 if (sk && sk->sk_prot == &tcpv6_prot && sk->sk_state == TCP_NEW_SYN_RECV)
10670 return (unsigned long)sk;
10671 #endif
10672
10673 return (unsigned long)NULL;
10674 }
10675
10676 const struct bpf_func_proto bpf_skc_to_tcp_request_sock_proto = {
10677 .func = bpf_skc_to_tcp_request_sock,
10678 .gpl_only = false,
10679 .ret_type = RET_PTR_TO_BTF_ID_OR_NULL,
10680 .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
10681 .ret_btf_id = &btf_sock_ids[BTF_SOCK_TYPE_TCP_REQ],
10682 };
10683
BPF_CALL_1(bpf_skc_to_udp6_sock,struct sock *,sk)10684 BPF_CALL_1(bpf_skc_to_udp6_sock, struct sock *, sk)
10685 {
10686 /* udp6_sock type is not generated in dwarf and hence btf,
10687 * trigger an explicit type generation here.
10688 */
10689 BTF_TYPE_EMIT(struct udp6_sock);
10690 if (sk && sk_fullsock(sk) && sk->sk_protocol == IPPROTO_UDP &&
10691 sk->sk_type == SOCK_DGRAM && sk->sk_family == AF_INET6)
10692 return (unsigned long)sk;
10693
10694 return (unsigned long)NULL;
10695 }
10696
10697 const struct bpf_func_proto bpf_skc_to_udp6_sock_proto = {
10698 .func = bpf_skc_to_udp6_sock,
10699 .gpl_only = false,
10700 .ret_type = RET_PTR_TO_BTF_ID_OR_NULL,
10701 .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
10702 .ret_btf_id = &btf_sock_ids[BTF_SOCK_TYPE_UDP6],
10703 };
10704
BPF_CALL_1(bpf_sock_from_file,struct file *,file)10705 BPF_CALL_1(bpf_sock_from_file, struct file *, file)
10706 {
10707 return (unsigned long)sock_from_file(file);
10708 }
10709
10710 BTF_ID_LIST(bpf_sock_from_file_btf_ids)
10711 BTF_ID(struct, socket)
10712 BTF_ID(struct, file)
10713
10714 const struct bpf_func_proto bpf_sock_from_file_proto = {
10715 .func = bpf_sock_from_file,
10716 .gpl_only = false,
10717 .ret_type = RET_PTR_TO_BTF_ID_OR_NULL,
10718 .ret_btf_id = &bpf_sock_from_file_btf_ids[0],
10719 .arg1_type = ARG_PTR_TO_BTF_ID,
10720 .arg1_btf_id = &bpf_sock_from_file_btf_ids[1],
10721 };
10722
10723 static const struct bpf_func_proto *
bpf_sk_base_func_proto(enum bpf_func_id func_id)10724 bpf_sk_base_func_proto(enum bpf_func_id func_id)
10725 {
10726 const struct bpf_func_proto *func;
10727
10728 switch (func_id) {
10729 case BPF_FUNC_skc_to_tcp6_sock:
10730 func = &bpf_skc_to_tcp6_sock_proto;
10731 break;
10732 case BPF_FUNC_skc_to_tcp_sock:
10733 func = &bpf_skc_to_tcp_sock_proto;
10734 break;
10735 case BPF_FUNC_skc_to_tcp_timewait_sock:
10736 func = &bpf_skc_to_tcp_timewait_sock_proto;
10737 break;
10738 case BPF_FUNC_skc_to_tcp_request_sock:
10739 func = &bpf_skc_to_tcp_request_sock_proto;
10740 break;
10741 case BPF_FUNC_skc_to_udp6_sock:
10742 func = &bpf_skc_to_udp6_sock_proto;
10743 break;
10744 default:
10745 return bpf_base_func_proto(func_id);
10746 }
10747
10748 if (!perfmon_capable())
10749 return NULL;
10750
10751 return func;
10752 }
10753