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