1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * common UDP/RAW code
4 * Linux INET6 implementation
5 *
6 * Authors:
7 * Pedro Roque <roque@di.fc.ul.pt>
8 */
9
10 #include <linux/capability.h>
11 #include <linux/errno.h>
12 #include <linux/types.h>
13 #include <linux/kernel.h>
14 #include <linux/interrupt.h>
15 #include <linux/socket.h>
16 #include <linux/sockios.h>
17 #include <linux/in6.h>
18 #include <linux/ipv6.h>
19 #include <linux/route.h>
20 #include <linux/slab.h>
21 #include <linux/export.h>
22
23 #include <net/ipv6.h>
24 #include <net/ndisc.h>
25 #include <net/addrconf.h>
26 #include <net/transp_v6.h>
27 #include <net/ip6_route.h>
28 #include <net/tcp_states.h>
29 #include <net/dsfield.h>
30 #include <net/sock_reuseport.h>
31
32 #include <linux/errqueue.h>
33 #include <linux/uaccess.h>
34
ipv6_mapped_addr_any(const struct in6_addr * a)35 static bool ipv6_mapped_addr_any(const struct in6_addr *a)
36 {
37 return ipv6_addr_v4mapped(a) && (a->s6_addr32[3] == 0);
38 }
39
ip6_datagram_flow_key_init(struct flowi6 * fl6,struct sock * sk)40 static void ip6_datagram_flow_key_init(struct flowi6 *fl6, struct sock *sk)
41 {
42 struct inet_sock *inet = inet_sk(sk);
43 struct ipv6_pinfo *np = inet6_sk(sk);
44
45 memset(fl6, 0, sizeof(*fl6));
46 fl6->flowi6_proto = sk->sk_protocol;
47 fl6->daddr = sk->sk_v6_daddr;
48 fl6->saddr = np->saddr;
49 fl6->flowi6_oif = sk->sk_bound_dev_if;
50 fl6->flowi6_mark = sk->sk_mark;
51 fl6->fl6_dport = inet->inet_dport;
52 fl6->fl6_sport = inet->inet_sport;
53 fl6->flowlabel = np->flow_label;
54 fl6->flowi6_uid = sk->sk_uid;
55
56 if (!fl6->flowi6_oif)
57 fl6->flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
58
59 if (!fl6->flowi6_oif && ipv6_addr_is_multicast(&fl6->daddr))
60 fl6->flowi6_oif = np->mcast_oif;
61
62 security_sk_classify_flow(sk, flowi6_to_flowi(fl6));
63 }
64
ip6_datagram_dst_update(struct sock * sk,bool fix_sk_saddr)65 int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr)
66 {
67 struct ip6_flowlabel *flowlabel = NULL;
68 struct in6_addr *final_p, final;
69 struct ipv6_txoptions *opt;
70 struct dst_entry *dst;
71 struct inet_sock *inet = inet_sk(sk);
72 struct ipv6_pinfo *np = inet6_sk(sk);
73 struct flowi6 fl6;
74 int err = 0;
75
76 if (np->sndflow && (np->flow_label & IPV6_FLOWLABEL_MASK)) {
77 flowlabel = fl6_sock_lookup(sk, np->flow_label);
78 if (IS_ERR(flowlabel))
79 return -EINVAL;
80 }
81 ip6_datagram_flow_key_init(&fl6, sk);
82
83 rcu_read_lock();
84 opt = flowlabel ? flowlabel->opt : rcu_dereference(np->opt);
85 final_p = fl6_update_dst(&fl6, opt, &final);
86 rcu_read_unlock();
87
88 dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
89 if (IS_ERR(dst)) {
90 err = PTR_ERR(dst);
91 goto out;
92 }
93
94 if (fix_sk_saddr) {
95 if (ipv6_addr_any(&np->saddr))
96 np->saddr = fl6.saddr;
97
98 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr)) {
99 sk->sk_v6_rcv_saddr = fl6.saddr;
100 inet->inet_rcv_saddr = LOOPBACK4_IPV6;
101 if (sk->sk_prot->rehash)
102 sk->sk_prot->rehash(sk);
103 }
104 }
105
106 ip6_sk_dst_store_flow(sk, dst, &fl6);
107
108 out:
109 fl6_sock_release(flowlabel);
110 return err;
111 }
112
ip6_datagram_release_cb(struct sock * sk)113 void ip6_datagram_release_cb(struct sock *sk)
114 {
115 struct dst_entry *dst;
116
117 if (ipv6_addr_v4mapped(&sk->sk_v6_daddr))
118 return;
119
120 rcu_read_lock();
121 dst = __sk_dst_get(sk);
122 if (!dst || !dst->obsolete ||
123 dst->ops->check(dst, inet6_sk(sk)->dst_cookie)) {
124 rcu_read_unlock();
125 return;
126 }
127 rcu_read_unlock();
128
129 ip6_datagram_dst_update(sk, false);
130 }
131 EXPORT_SYMBOL_GPL(ip6_datagram_release_cb);
132
__ip6_datagram_connect(struct sock * sk,struct sockaddr * uaddr,int addr_len)133 int __ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr,
134 int addr_len)
135 {
136 struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr;
137 struct inet_sock *inet = inet_sk(sk);
138 struct ipv6_pinfo *np = inet6_sk(sk);
139 struct in6_addr *daddr, old_daddr;
140 __be32 fl6_flowlabel = 0;
141 __be32 old_fl6_flowlabel;
142 __be16 old_dport;
143 int addr_type;
144 int err;
145
146 if (usin->sin6_family == AF_INET) {
147 if (__ipv6_only_sock(sk))
148 return -EAFNOSUPPORT;
149 err = __ip4_datagram_connect(sk, uaddr, addr_len);
150 goto ipv4_connected;
151 }
152
153 if (addr_len < SIN6_LEN_RFC2133)
154 return -EINVAL;
155
156 if (usin->sin6_family != AF_INET6)
157 return -EAFNOSUPPORT;
158
159 if (np->sndflow)
160 fl6_flowlabel = usin->sin6_flowinfo & IPV6_FLOWINFO_MASK;
161
162 if (ipv6_addr_any(&usin->sin6_addr)) {
163 /*
164 * connect to self
165 */
166 if (ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr))
167 ipv6_addr_set_v4mapped(htonl(INADDR_LOOPBACK),
168 &usin->sin6_addr);
169 else
170 usin->sin6_addr = in6addr_loopback;
171 }
172
173 addr_type = ipv6_addr_type(&usin->sin6_addr);
174
175 daddr = &usin->sin6_addr;
176
177 if (addr_type & IPV6_ADDR_MAPPED) {
178 struct sockaddr_in sin;
179
180 if (__ipv6_only_sock(sk)) {
181 err = -ENETUNREACH;
182 goto out;
183 }
184 sin.sin_family = AF_INET;
185 sin.sin_addr.s_addr = daddr->s6_addr32[3];
186 sin.sin_port = usin->sin6_port;
187
188 err = __ip4_datagram_connect(sk,
189 (struct sockaddr *) &sin,
190 sizeof(sin));
191
192 ipv4_connected:
193 if (err)
194 goto out;
195
196 ipv6_addr_set_v4mapped(inet->inet_daddr, &sk->sk_v6_daddr);
197
198 if (ipv6_addr_any(&np->saddr) ||
199 ipv6_mapped_addr_any(&np->saddr))
200 ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr);
201
202 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr) ||
203 ipv6_mapped_addr_any(&sk->sk_v6_rcv_saddr)) {
204 ipv6_addr_set_v4mapped(inet->inet_rcv_saddr,
205 &sk->sk_v6_rcv_saddr);
206 if (sk->sk_prot->rehash)
207 sk->sk_prot->rehash(sk);
208 }
209
210 goto out;
211 }
212
213 if (__ipv6_addr_needs_scope_id(addr_type)) {
214 if (addr_len >= sizeof(struct sockaddr_in6) &&
215 usin->sin6_scope_id) {
216 if (!sk_dev_equal_l3scope(sk, usin->sin6_scope_id)) {
217 err = -EINVAL;
218 goto out;
219 }
220 sk->sk_bound_dev_if = usin->sin6_scope_id;
221 }
222
223 if (!sk->sk_bound_dev_if && (addr_type & IPV6_ADDR_MULTICAST))
224 sk->sk_bound_dev_if = np->mcast_oif;
225
226 /* Connect to link-local address requires an interface */
227 if (!sk->sk_bound_dev_if) {
228 err = -EINVAL;
229 goto out;
230 }
231 }
232
233 /* save the current peer information before updating it */
234 old_daddr = sk->sk_v6_daddr;
235 old_fl6_flowlabel = np->flow_label;
236 old_dport = inet->inet_dport;
237
238 sk->sk_v6_daddr = *daddr;
239 np->flow_label = fl6_flowlabel;
240 inet->inet_dport = usin->sin6_port;
241
242 /*
243 * Check for a route to destination an obtain the
244 * destination cache for it.
245 */
246
247 err = ip6_datagram_dst_update(sk, true);
248 if (err) {
249 /* Restore the socket peer info, to keep it consistent with
250 * the old socket state
251 */
252 sk->sk_v6_daddr = old_daddr;
253 np->flow_label = old_fl6_flowlabel;
254 inet->inet_dport = old_dport;
255 goto out;
256 }
257
258 reuseport_has_conns(sk, true);
259 sk->sk_state = TCP_ESTABLISHED;
260 sk_set_txhash(sk);
261 out:
262 return err;
263 }
264 EXPORT_SYMBOL_GPL(__ip6_datagram_connect);
265
ip6_datagram_connect(struct sock * sk,struct sockaddr * uaddr,int addr_len)266 int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
267 {
268 int res;
269
270 lock_sock(sk);
271 res = __ip6_datagram_connect(sk, uaddr, addr_len);
272 release_sock(sk);
273 return res;
274 }
275 EXPORT_SYMBOL_GPL(ip6_datagram_connect);
276
ip6_datagram_connect_v6_only(struct sock * sk,struct sockaddr * uaddr,int addr_len)277 int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *uaddr,
278 int addr_len)
279 {
280 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, uaddr);
281 if (sin6->sin6_family != AF_INET6)
282 return -EAFNOSUPPORT;
283 return ip6_datagram_connect(sk, uaddr, addr_len);
284 }
285 EXPORT_SYMBOL_GPL(ip6_datagram_connect_v6_only);
286
ipv6_icmp_error(struct sock * sk,struct sk_buff * skb,int err,__be16 port,u32 info,u8 * payload)287 void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
288 __be16 port, u32 info, u8 *payload)
289 {
290 struct ipv6_pinfo *np = inet6_sk(sk);
291 struct icmp6hdr *icmph = icmp6_hdr(skb);
292 struct sock_exterr_skb *serr;
293
294 if (!np->recverr)
295 return;
296
297 skb = skb_clone(skb, GFP_ATOMIC);
298 if (!skb)
299 return;
300
301 skb->protocol = htons(ETH_P_IPV6);
302
303 serr = SKB_EXT_ERR(skb);
304 serr->ee.ee_errno = err;
305 serr->ee.ee_origin = SO_EE_ORIGIN_ICMP6;
306 serr->ee.ee_type = icmph->icmp6_type;
307 serr->ee.ee_code = icmph->icmp6_code;
308 serr->ee.ee_pad = 0;
309 serr->ee.ee_info = info;
310 serr->ee.ee_data = 0;
311 serr->addr_offset = (u8 *)&(((struct ipv6hdr *)(icmph + 1))->daddr) -
312 skb_network_header(skb);
313 serr->port = port;
314
315 __skb_pull(skb, payload - skb->data);
316 skb_reset_transport_header(skb);
317
318 if (sock_queue_err_skb(sk, skb))
319 kfree_skb(skb);
320 }
321
ipv6_local_error(struct sock * sk,int err,struct flowi6 * fl6,u32 info)322 void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info)
323 {
324 const struct ipv6_pinfo *np = inet6_sk(sk);
325 struct sock_exterr_skb *serr;
326 struct ipv6hdr *iph;
327 struct sk_buff *skb;
328
329 if (!np->recverr)
330 return;
331
332 skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
333 if (!skb)
334 return;
335
336 skb->protocol = htons(ETH_P_IPV6);
337
338 skb_put(skb, sizeof(struct ipv6hdr));
339 skb_reset_network_header(skb);
340 iph = ipv6_hdr(skb);
341 iph->daddr = fl6->daddr;
342 ip6_flow_hdr(iph, 0, 0);
343
344 serr = SKB_EXT_ERR(skb);
345 serr->ee.ee_errno = err;
346 serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
347 serr->ee.ee_type = 0;
348 serr->ee.ee_code = 0;
349 serr->ee.ee_pad = 0;
350 serr->ee.ee_info = info;
351 serr->ee.ee_data = 0;
352 serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
353 serr->port = fl6->fl6_dport;
354
355 __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
356 skb_reset_transport_header(skb);
357
358 if (sock_queue_err_skb(sk, skb))
359 kfree_skb(skb);
360 }
361
ipv6_local_rxpmtu(struct sock * sk,struct flowi6 * fl6,u32 mtu)362 void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu)
363 {
364 struct ipv6_pinfo *np = inet6_sk(sk);
365 struct ipv6hdr *iph;
366 struct sk_buff *skb;
367 struct ip6_mtuinfo *mtu_info;
368
369 if (!np->rxopt.bits.rxpmtu)
370 return;
371
372 skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
373 if (!skb)
374 return;
375
376 skb_put(skb, sizeof(struct ipv6hdr));
377 skb_reset_network_header(skb);
378 iph = ipv6_hdr(skb);
379 iph->daddr = fl6->daddr;
380
381 mtu_info = IP6CBMTU(skb);
382
383 mtu_info->ip6m_mtu = mtu;
384 mtu_info->ip6m_addr.sin6_family = AF_INET6;
385 mtu_info->ip6m_addr.sin6_port = 0;
386 mtu_info->ip6m_addr.sin6_flowinfo = 0;
387 mtu_info->ip6m_addr.sin6_scope_id = fl6->flowi6_oif;
388 mtu_info->ip6m_addr.sin6_addr = ipv6_hdr(skb)->daddr;
389
390 __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
391 skb_reset_transport_header(skb);
392
393 skb = xchg(&np->rxpmtu, skb);
394 kfree_skb(skb);
395 }
396
397 /* For some errors we have valid addr_offset even with zero payload and
398 * zero port. Also, addr_offset should be supported if port is set.
399 */
ipv6_datagram_support_addr(struct sock_exterr_skb * serr)400 static inline bool ipv6_datagram_support_addr(struct sock_exterr_skb *serr)
401 {
402 return serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6 ||
403 serr->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
404 serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL || serr->port;
405 }
406
407 /* IPv6 supports cmsg on all origins aside from SO_EE_ORIGIN_LOCAL.
408 *
409 * At one point, excluding local errors was a quick test to identify icmp/icmp6
410 * errors. This is no longer true, but the test remained, so the v6 stack,
411 * unlike v4, also honors cmsg requests on all wifi and timestamp errors.
412 */
ip6_datagram_support_cmsg(struct sk_buff * skb,struct sock_exterr_skb * serr)413 static bool ip6_datagram_support_cmsg(struct sk_buff *skb,
414 struct sock_exterr_skb *serr)
415 {
416 if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
417 serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6)
418 return true;
419
420 if (serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL)
421 return false;
422
423 if (!IP6CB(skb)->iif)
424 return false;
425
426 return true;
427 }
428
429 /*
430 * Handle MSG_ERRQUEUE
431 */
ipv6_recv_error(struct sock * sk,struct msghdr * msg,int len,int * addr_len)432 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
433 {
434 struct ipv6_pinfo *np = inet6_sk(sk);
435 struct sock_exterr_skb *serr;
436 struct sk_buff *skb;
437 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name);
438 struct {
439 struct sock_extended_err ee;
440 struct sockaddr_in6 offender;
441 } errhdr;
442 int err;
443 int copied;
444
445 err = -EAGAIN;
446 skb = sock_dequeue_err_skb(sk);
447 if (!skb)
448 goto out;
449
450 copied = skb->len;
451 if (copied > len) {
452 msg->msg_flags |= MSG_TRUNC;
453 copied = len;
454 }
455 err = skb_copy_datagram_msg(skb, 0, msg, copied);
456 if (unlikely(err)) {
457 kfree_skb(skb);
458 return err;
459 }
460 sock_recv_timestamp(msg, sk, skb);
461
462 serr = SKB_EXT_ERR(skb);
463
464 if (sin && ipv6_datagram_support_addr(serr)) {
465 const unsigned char *nh = skb_network_header(skb);
466 sin->sin6_family = AF_INET6;
467 sin->sin6_flowinfo = 0;
468 sin->sin6_port = serr->port;
469 if (skb->protocol == htons(ETH_P_IPV6)) {
470 const struct ipv6hdr *ip6h = container_of((struct in6_addr *)(nh + serr->addr_offset),
471 struct ipv6hdr, daddr);
472 sin->sin6_addr = ip6h->daddr;
473 if (np->sndflow)
474 sin->sin6_flowinfo = ip6_flowinfo(ip6h);
475 sin->sin6_scope_id =
476 ipv6_iface_scope_id(&sin->sin6_addr,
477 IP6CB(skb)->iif);
478 } else {
479 ipv6_addr_set_v4mapped(*(__be32 *)(nh + serr->addr_offset),
480 &sin->sin6_addr);
481 sin->sin6_scope_id = 0;
482 }
483 *addr_len = sizeof(*sin);
484 }
485
486 memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
487 sin = &errhdr.offender;
488 memset(sin, 0, sizeof(*sin));
489
490 if (ip6_datagram_support_cmsg(skb, serr)) {
491 sin->sin6_family = AF_INET6;
492 if (np->rxopt.all)
493 ip6_datagram_recv_common_ctl(sk, msg, skb);
494 if (skb->protocol == htons(ETH_P_IPV6)) {
495 sin->sin6_addr = ipv6_hdr(skb)->saddr;
496 if (np->rxopt.all)
497 ip6_datagram_recv_specific_ctl(sk, msg, skb);
498 sin->sin6_scope_id =
499 ipv6_iface_scope_id(&sin->sin6_addr,
500 IP6CB(skb)->iif);
501 } else {
502 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
503 &sin->sin6_addr);
504 if (inet_sk(sk)->cmsg_flags)
505 ip_cmsg_recv(msg, skb);
506 }
507 }
508
509 put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr);
510
511 /* Now we could try to dump offended packet options */
512
513 msg->msg_flags |= MSG_ERRQUEUE;
514 err = copied;
515
516 consume_skb(skb);
517 out:
518 return err;
519 }
520 EXPORT_SYMBOL_GPL(ipv6_recv_error);
521
522 /*
523 * Handle IPV6_RECVPATHMTU
524 */
ipv6_recv_rxpmtu(struct sock * sk,struct msghdr * msg,int len,int * addr_len)525 int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len,
526 int *addr_len)
527 {
528 struct ipv6_pinfo *np = inet6_sk(sk);
529 struct sk_buff *skb;
530 struct ip6_mtuinfo mtu_info;
531 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name);
532 int err;
533 int copied;
534
535 err = -EAGAIN;
536 skb = xchg(&np->rxpmtu, NULL);
537 if (!skb)
538 goto out;
539
540 copied = skb->len;
541 if (copied > len) {
542 msg->msg_flags |= MSG_TRUNC;
543 copied = len;
544 }
545 err = skb_copy_datagram_msg(skb, 0, msg, copied);
546 if (err)
547 goto out_free_skb;
548
549 sock_recv_timestamp(msg, sk, skb);
550
551 memcpy(&mtu_info, IP6CBMTU(skb), sizeof(mtu_info));
552
553 if (sin) {
554 sin->sin6_family = AF_INET6;
555 sin->sin6_flowinfo = 0;
556 sin->sin6_port = 0;
557 sin->sin6_scope_id = mtu_info.ip6m_addr.sin6_scope_id;
558 sin->sin6_addr = mtu_info.ip6m_addr.sin6_addr;
559 *addr_len = sizeof(*sin);
560 }
561
562 put_cmsg(msg, SOL_IPV6, IPV6_PATHMTU, sizeof(mtu_info), &mtu_info);
563
564 err = copied;
565
566 out_free_skb:
567 kfree_skb(skb);
568 out:
569 return err;
570 }
571
572
ip6_datagram_recv_common_ctl(struct sock * sk,struct msghdr * msg,struct sk_buff * skb)573 void ip6_datagram_recv_common_ctl(struct sock *sk, struct msghdr *msg,
574 struct sk_buff *skb)
575 {
576 struct ipv6_pinfo *np = inet6_sk(sk);
577 bool is_ipv6 = skb->protocol == htons(ETH_P_IPV6);
578
579 if (np->rxopt.bits.rxinfo) {
580 struct in6_pktinfo src_info;
581
582 if (is_ipv6) {
583 src_info.ipi6_ifindex = IP6CB(skb)->iif;
584 src_info.ipi6_addr = ipv6_hdr(skb)->daddr;
585 } else {
586 src_info.ipi6_ifindex =
587 PKTINFO_SKB_CB(skb)->ipi_ifindex;
588 ipv6_addr_set_v4mapped(ip_hdr(skb)->daddr,
589 &src_info.ipi6_addr);
590 }
591
592 if (src_info.ipi6_ifindex >= 0)
593 put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO,
594 sizeof(src_info), &src_info);
595 }
596 }
597
ip6_datagram_recv_specific_ctl(struct sock * sk,struct msghdr * msg,struct sk_buff * skb)598 void ip6_datagram_recv_specific_ctl(struct sock *sk, struct msghdr *msg,
599 struct sk_buff *skb)
600 {
601 struct ipv6_pinfo *np = inet6_sk(sk);
602 struct inet6_skb_parm *opt = IP6CB(skb);
603 unsigned char *nh = skb_network_header(skb);
604
605 if (np->rxopt.bits.rxhlim) {
606 int hlim = ipv6_hdr(skb)->hop_limit;
607 put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
608 }
609
610 if (np->rxopt.bits.rxtclass) {
611 int tclass = ipv6_get_dsfield(ipv6_hdr(skb));
612 put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
613 }
614
615 if (np->rxopt.bits.rxflow) {
616 __be32 flowinfo = ip6_flowinfo((struct ipv6hdr *)nh);
617 if (flowinfo)
618 put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
619 }
620
621 /* HbH is allowed only once */
622 if (np->rxopt.bits.hopopts && (opt->flags & IP6SKB_HOPBYHOP)) {
623 u8 *ptr = nh + sizeof(struct ipv6hdr);
624 put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr);
625 }
626
627 if (opt->lastopt &&
628 (np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) {
629 /*
630 * Silly enough, but we need to reparse in order to
631 * report extension headers (except for HbH)
632 * in order.
633 *
634 * Also note that IPV6_RECVRTHDRDSTOPTS is NOT
635 * (and WILL NOT be) defined because
636 * IPV6_RECVDSTOPTS is more generic. --yoshfuji
637 */
638 unsigned int off = sizeof(struct ipv6hdr);
639 u8 nexthdr = ipv6_hdr(skb)->nexthdr;
640
641 while (off <= opt->lastopt) {
642 unsigned int len;
643 u8 *ptr = nh + off;
644
645 switch (nexthdr) {
646 case IPPROTO_DSTOPTS:
647 nexthdr = ptr[0];
648 len = (ptr[1] + 1) << 3;
649 if (np->rxopt.bits.dstopts)
650 put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, ptr);
651 break;
652 case IPPROTO_ROUTING:
653 nexthdr = ptr[0];
654 len = (ptr[1] + 1) << 3;
655 if (np->rxopt.bits.srcrt)
656 put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, ptr);
657 break;
658 case IPPROTO_AH:
659 nexthdr = ptr[0];
660 len = (ptr[1] + 2) << 2;
661 break;
662 default:
663 nexthdr = ptr[0];
664 len = (ptr[1] + 1) << 3;
665 break;
666 }
667
668 off += len;
669 }
670 }
671
672 /* socket options in old style */
673 if (np->rxopt.bits.rxoinfo) {
674 struct in6_pktinfo src_info;
675
676 src_info.ipi6_ifindex = opt->iif;
677 src_info.ipi6_addr = ipv6_hdr(skb)->daddr;
678 put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
679 }
680 if (np->rxopt.bits.rxohlim) {
681 int hlim = ipv6_hdr(skb)->hop_limit;
682 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
683 }
684 if (np->rxopt.bits.ohopopts && (opt->flags & IP6SKB_HOPBYHOP)) {
685 u8 *ptr = nh + sizeof(struct ipv6hdr);
686 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, (ptr[1]+1)<<3, ptr);
687 }
688 if (np->rxopt.bits.odstopts && opt->dst0) {
689 u8 *ptr = nh + opt->dst0;
690 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
691 }
692 if (np->rxopt.bits.osrcrt && opt->srcrt) {
693 struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt);
694 put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, (rthdr->hdrlen+1) << 3, rthdr);
695 }
696 if (np->rxopt.bits.odstopts && opt->dst1) {
697 u8 *ptr = nh + opt->dst1;
698 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
699 }
700 if (np->rxopt.bits.rxorigdstaddr) {
701 struct sockaddr_in6 sin6;
702 __be16 _ports[2], *ports;
703
704 ports = skb_header_pointer(skb, skb_transport_offset(skb),
705 sizeof(_ports), &_ports);
706 if (ports) {
707 /* All current transport protocols have the port numbers in the
708 * first four bytes of the transport header and this function is
709 * written with this assumption in mind.
710 */
711 sin6.sin6_family = AF_INET6;
712 sin6.sin6_addr = ipv6_hdr(skb)->daddr;
713 sin6.sin6_port = ports[1];
714 sin6.sin6_flowinfo = 0;
715 sin6.sin6_scope_id =
716 ipv6_iface_scope_id(&ipv6_hdr(skb)->daddr,
717 opt->iif);
718
719 put_cmsg(msg, SOL_IPV6, IPV6_ORIGDSTADDR, sizeof(sin6), &sin6);
720 }
721 }
722 if (np->rxopt.bits.recvfragsize && opt->frag_max_size) {
723 int val = opt->frag_max_size;
724
725 put_cmsg(msg, SOL_IPV6, IPV6_RECVFRAGSIZE, sizeof(val), &val);
726 }
727 }
728
ip6_datagram_recv_ctl(struct sock * sk,struct msghdr * msg,struct sk_buff * skb)729 void ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg,
730 struct sk_buff *skb)
731 {
732 ip6_datagram_recv_common_ctl(sk, msg, skb);
733 ip6_datagram_recv_specific_ctl(sk, msg, skb);
734 }
735 EXPORT_SYMBOL_GPL(ip6_datagram_recv_ctl);
736
ip6_datagram_send_ctl(struct net * net,struct sock * sk,struct msghdr * msg,struct flowi6 * fl6,struct ipcm6_cookie * ipc6)737 int ip6_datagram_send_ctl(struct net *net, struct sock *sk,
738 struct msghdr *msg, struct flowi6 *fl6,
739 struct ipcm6_cookie *ipc6)
740 {
741 struct in6_pktinfo *src_info;
742 struct cmsghdr *cmsg;
743 struct ipv6_rt_hdr *rthdr;
744 struct ipv6_opt_hdr *hdr;
745 struct ipv6_txoptions *opt = ipc6->opt;
746 int len;
747 int err = 0;
748
749 for_each_cmsghdr(cmsg, msg) {
750 int addr_type;
751
752 if (!CMSG_OK(msg, cmsg)) {
753 err = -EINVAL;
754 goto exit_f;
755 }
756
757 if (cmsg->cmsg_level == SOL_SOCKET) {
758 err = __sock_cmsg_send(sk, msg, cmsg, &ipc6->sockc);
759 if (err)
760 return err;
761 continue;
762 }
763
764 if (cmsg->cmsg_level != SOL_IPV6)
765 continue;
766
767 switch (cmsg->cmsg_type) {
768 case IPV6_PKTINFO:
769 case IPV6_2292PKTINFO:
770 {
771 struct net_device *dev = NULL;
772 int src_idx;
773
774 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) {
775 err = -EINVAL;
776 goto exit_f;
777 }
778
779 src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
780 src_idx = src_info->ipi6_ifindex;
781
782 if (src_idx) {
783 if (fl6->flowi6_oif &&
784 src_idx != fl6->flowi6_oif &&
785 (sk->sk_bound_dev_if != fl6->flowi6_oif ||
786 !sk_dev_equal_l3scope(sk, src_idx)))
787 return -EINVAL;
788 fl6->flowi6_oif = src_idx;
789 }
790
791 addr_type = __ipv6_addr_type(&src_info->ipi6_addr);
792
793 rcu_read_lock();
794 if (fl6->flowi6_oif) {
795 dev = dev_get_by_index_rcu(net, fl6->flowi6_oif);
796 if (!dev) {
797 rcu_read_unlock();
798 return -ENODEV;
799 }
800 } else if (addr_type & IPV6_ADDR_LINKLOCAL) {
801 rcu_read_unlock();
802 return -EINVAL;
803 }
804
805 if (addr_type != IPV6_ADDR_ANY) {
806 int strict = __ipv6_addr_src_scope(addr_type) <= IPV6_ADDR_SCOPE_LINKLOCAL;
807 if (!ipv6_can_nonlocal_bind(net, inet_sk(sk)) &&
808 !ipv6_chk_addr_and_flags(net, &src_info->ipi6_addr,
809 dev, !strict, 0,
810 IFA_F_TENTATIVE) &&
811 !ipv6_chk_acast_addr_src(net, dev,
812 &src_info->ipi6_addr))
813 err = -EINVAL;
814 else
815 fl6->saddr = src_info->ipi6_addr;
816 }
817
818 rcu_read_unlock();
819
820 if (err)
821 goto exit_f;
822
823 break;
824 }
825
826 case IPV6_FLOWINFO:
827 if (cmsg->cmsg_len < CMSG_LEN(4)) {
828 err = -EINVAL;
829 goto exit_f;
830 }
831
832 if (fl6->flowlabel&IPV6_FLOWINFO_MASK) {
833 if ((fl6->flowlabel^*(__be32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) {
834 err = -EINVAL;
835 goto exit_f;
836 }
837 }
838 fl6->flowlabel = IPV6_FLOWINFO_MASK & *(__be32 *)CMSG_DATA(cmsg);
839 break;
840
841 case IPV6_2292HOPOPTS:
842 case IPV6_HOPOPTS:
843 if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
844 err = -EINVAL;
845 goto exit_f;
846 }
847
848 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
849 len = ((hdr->hdrlen + 1) << 3);
850 if (cmsg->cmsg_len < CMSG_LEN(len)) {
851 err = -EINVAL;
852 goto exit_f;
853 }
854 if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
855 err = -EPERM;
856 goto exit_f;
857 }
858 opt->opt_nflen += len;
859 opt->hopopt = hdr;
860 break;
861
862 case IPV6_2292DSTOPTS:
863 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
864 err = -EINVAL;
865 goto exit_f;
866 }
867
868 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
869 len = ((hdr->hdrlen + 1) << 3);
870 if (cmsg->cmsg_len < CMSG_LEN(len)) {
871 err = -EINVAL;
872 goto exit_f;
873 }
874 if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
875 err = -EPERM;
876 goto exit_f;
877 }
878 if (opt->dst1opt) {
879 err = -EINVAL;
880 goto exit_f;
881 }
882 opt->opt_flen += len;
883 opt->dst1opt = hdr;
884 break;
885
886 case IPV6_DSTOPTS:
887 case IPV6_RTHDRDSTOPTS:
888 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
889 err = -EINVAL;
890 goto exit_f;
891 }
892
893 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
894 len = ((hdr->hdrlen + 1) << 3);
895 if (cmsg->cmsg_len < CMSG_LEN(len)) {
896 err = -EINVAL;
897 goto exit_f;
898 }
899 if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
900 err = -EPERM;
901 goto exit_f;
902 }
903 if (cmsg->cmsg_type == IPV6_DSTOPTS) {
904 opt->opt_flen += len;
905 opt->dst1opt = hdr;
906 } else {
907 opt->opt_nflen += len;
908 opt->dst0opt = hdr;
909 }
910 break;
911
912 case IPV6_2292RTHDR:
913 case IPV6_RTHDR:
914 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) {
915 err = -EINVAL;
916 goto exit_f;
917 }
918
919 rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg);
920
921 switch (rthdr->type) {
922 #if IS_ENABLED(CONFIG_IPV6_MIP6)
923 case IPV6_SRCRT_TYPE_2:
924 if (rthdr->hdrlen != 2 ||
925 rthdr->segments_left != 1) {
926 err = -EINVAL;
927 goto exit_f;
928 }
929 break;
930 #endif
931 default:
932 err = -EINVAL;
933 goto exit_f;
934 }
935
936 len = ((rthdr->hdrlen + 1) << 3);
937
938 if (cmsg->cmsg_len < CMSG_LEN(len)) {
939 err = -EINVAL;
940 goto exit_f;
941 }
942
943 /* segments left must also match */
944 if ((rthdr->hdrlen >> 1) != rthdr->segments_left) {
945 err = -EINVAL;
946 goto exit_f;
947 }
948
949 opt->opt_nflen += len;
950 opt->srcrt = rthdr;
951
952 if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) {
953 int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3);
954
955 opt->opt_nflen += dsthdrlen;
956 opt->dst0opt = opt->dst1opt;
957 opt->dst1opt = NULL;
958 opt->opt_flen -= dsthdrlen;
959 }
960
961 break;
962
963 case IPV6_2292HOPLIMIT:
964 case IPV6_HOPLIMIT:
965 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
966 err = -EINVAL;
967 goto exit_f;
968 }
969
970 ipc6->hlimit = *(int *)CMSG_DATA(cmsg);
971 if (ipc6->hlimit < -1 || ipc6->hlimit > 0xff) {
972 err = -EINVAL;
973 goto exit_f;
974 }
975
976 break;
977
978 case IPV6_TCLASS:
979 {
980 int tc;
981
982 err = -EINVAL;
983 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
984 goto exit_f;
985
986 tc = *(int *)CMSG_DATA(cmsg);
987 if (tc < -1 || tc > 0xff)
988 goto exit_f;
989
990 err = 0;
991 ipc6->tclass = tc;
992
993 break;
994 }
995
996 case IPV6_DONTFRAG:
997 {
998 int df;
999
1000 err = -EINVAL;
1001 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
1002 goto exit_f;
1003
1004 df = *(int *)CMSG_DATA(cmsg);
1005 if (df < 0 || df > 1)
1006 goto exit_f;
1007
1008 err = 0;
1009 ipc6->dontfrag = df;
1010
1011 break;
1012 }
1013 default:
1014 net_dbg_ratelimited("invalid cmsg type: %d\n",
1015 cmsg->cmsg_type);
1016 err = -EINVAL;
1017 goto exit_f;
1018 }
1019 }
1020
1021 exit_f:
1022 return err;
1023 }
1024 EXPORT_SYMBOL_GPL(ip6_datagram_send_ctl);
1025
__ip6_dgram_sock_seq_show(struct seq_file * seq,struct sock * sp,__u16 srcp,__u16 destp,int rqueue,int bucket)1026 void __ip6_dgram_sock_seq_show(struct seq_file *seq, struct sock *sp,
1027 __u16 srcp, __u16 destp, int rqueue, int bucket)
1028 {
1029 const struct in6_addr *dest, *src;
1030
1031 dest = &sp->sk_v6_daddr;
1032 src = &sp->sk_v6_rcv_saddr;
1033 seq_printf(seq,
1034 "%5d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1035 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %u\n",
1036 bucket,
1037 src->s6_addr32[0], src->s6_addr32[1],
1038 src->s6_addr32[2], src->s6_addr32[3], srcp,
1039 dest->s6_addr32[0], dest->s6_addr32[1],
1040 dest->s6_addr32[2], dest->s6_addr32[3], destp,
1041 sp->sk_state,
1042 sk_wmem_alloc_get(sp),
1043 rqueue,
1044 0, 0L, 0,
1045 from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)),
1046 0,
1047 sock_i_ino(sp),
1048 refcount_read(&sp->sk_refcnt), sp,
1049 atomic_read(&sp->sk_drops));
1050 }
1051
