Loading...
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 <asm/uaccess.h>
37
38static bool ipv6_mapped_addr_any(const struct in6_addr *a)
39{
40 return ipv6_addr_v4mapped(a) && (a->s6_addr32[3] == 0);
41}
42
43static 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
58 if (!fl6->flowi6_oif)
59 fl6->flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
60
61 if (!fl6->flowi6_oif && ipv6_addr_is_multicast(&fl6->daddr))
62 fl6->flowi6_oif = np->mcast_oif;
63
64 security_sk_classify_flow(sk, flowi6_to_flowi(fl6));
65}
66
67int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr)
68{
69 struct ip6_flowlabel *flowlabel = NULL;
70 struct in6_addr *final_p, final;
71 struct ipv6_txoptions *opt;
72 struct dst_entry *dst;
73 struct inet_sock *inet = inet_sk(sk);
74 struct ipv6_pinfo *np = inet6_sk(sk);
75 struct flowi6 fl6;
76 int err = 0;
77
78 if (np->sndflow && (np->flow_label & IPV6_FLOWLABEL_MASK)) {
79 flowlabel = fl6_sock_lookup(sk, np->flow_label);
80 if (!flowlabel)
81 return -EINVAL;
82 }
83 ip6_datagram_flow_key_init(&fl6, sk);
84
85 rcu_read_lock();
86 opt = flowlabel ? flowlabel->opt : rcu_dereference(np->opt);
87 final_p = fl6_update_dst(&fl6, opt, &final);
88 rcu_read_unlock();
89
90 dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
91 if (IS_ERR(dst)) {
92 err = PTR_ERR(dst);
93 goto out;
94 }
95
96 if (fix_sk_saddr) {
97 if (ipv6_addr_any(&np->saddr))
98 np->saddr = fl6.saddr;
99
100 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr)) {
101 sk->sk_v6_rcv_saddr = fl6.saddr;
102 inet->inet_rcv_saddr = LOOPBACK4_IPV6;
103 if (sk->sk_prot->rehash)
104 sk->sk_prot->rehash(sk);
105 }
106 }
107
108 ip6_dst_store(sk, dst,
109 ipv6_addr_equal(&fl6.daddr, &sk->sk_v6_daddr) ?
110 &sk->sk_v6_daddr : NULL,
111#ifdef CONFIG_IPV6_SUBTREES
112 ipv6_addr_equal(&fl6.saddr, &np->saddr) ?
113 &np->saddr :
114#endif
115 NULL);
116
117out:
118 fl6_sock_release(flowlabel);
119 return err;
120}
121
122void ip6_datagram_release_cb(struct sock *sk)
123{
124 struct dst_entry *dst;
125
126 if (ipv6_addr_v4mapped(&sk->sk_v6_daddr))
127 return;
128
129 rcu_read_lock();
130 dst = __sk_dst_get(sk);
131 if (!dst || !dst->obsolete ||
132 dst->ops->check(dst, inet6_sk(sk)->dst_cookie)) {
133 rcu_read_unlock();
134 return;
135 }
136 rcu_read_unlock();
137
138 ip6_datagram_dst_update(sk, false);
139}
140EXPORT_SYMBOL_GPL(ip6_datagram_release_cb);
141
142static int __ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
143{
144 struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr;
145 struct inet_sock *inet = inet_sk(sk);
146 struct ipv6_pinfo *np = inet6_sk(sk);
147 struct in6_addr *daddr;
148 int addr_type;
149 int err;
150 __be32 fl6_flowlabel = 0;
151
152 if (usin->sin6_family == AF_INET) {
153 if (__ipv6_only_sock(sk))
154 return -EAFNOSUPPORT;
155 err = __ip4_datagram_connect(sk, uaddr, addr_len);
156 goto ipv4_connected;
157 }
158
159 if (addr_len < SIN6_LEN_RFC2133)
160 return -EINVAL;
161
162 if (usin->sin6_family != AF_INET6)
163 return -EAFNOSUPPORT;
164
165 if (np->sndflow)
166 fl6_flowlabel = usin->sin6_flowinfo & IPV6_FLOWINFO_MASK;
167
168 addr_type = ipv6_addr_type(&usin->sin6_addr);
169
170 if (addr_type == IPV6_ADDR_ANY) {
171 /*
172 * connect to self
173 */
174 usin->sin6_addr.s6_addr[15] = 0x01;
175 }
176
177 daddr = &usin->sin6_addr;
178
179 if (addr_type == IPV6_ADDR_MAPPED) {
180 struct sockaddr_in sin;
181
182 if (__ipv6_only_sock(sk)) {
183 err = -ENETUNREACH;
184 goto out;
185 }
186 sin.sin_family = AF_INET;
187 sin.sin_addr.s_addr = daddr->s6_addr32[3];
188 sin.sin_port = usin->sin6_port;
189
190 err = __ip4_datagram_connect(sk,
191 (struct sockaddr *) &sin,
192 sizeof(sin));
193
194ipv4_connected:
195 if (err)
196 goto out;
197
198 ipv6_addr_set_v4mapped(inet->inet_daddr, &sk->sk_v6_daddr);
199
200 if (ipv6_addr_any(&np->saddr) ||
201 ipv6_mapped_addr_any(&np->saddr))
202 ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr);
203
204 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr) ||
205 ipv6_mapped_addr_any(&sk->sk_v6_rcv_saddr)) {
206 ipv6_addr_set_v4mapped(inet->inet_rcv_saddr,
207 &sk->sk_v6_rcv_saddr);
208 if (sk->sk_prot->rehash)
209 sk->sk_prot->rehash(sk);
210 }
211
212 goto out;
213 }
214
215 if (__ipv6_addr_needs_scope_id(addr_type)) {
216 if (addr_len >= sizeof(struct sockaddr_in6) &&
217 usin->sin6_scope_id) {
218 if (sk->sk_bound_dev_if &&
219 sk->sk_bound_dev_if != 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 sk->sk_v6_daddr = *daddr;
237 np->flow_label = fl6_flowlabel;
238
239 inet->inet_dport = usin->sin6_port;
240
241 /*
242 * Check for a route to destination an obtain the
243 * destination cache for it.
244 */
245
246 err = ip6_datagram_dst_update(sk, true);
247 if (err)
248 goto out;
249
250 sk->sk_state = TCP_ESTABLISHED;
251 sk_set_txhash(sk);
252out:
253 return err;
254}
255
256int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
257{
258 int res;
259
260 lock_sock(sk);
261 res = __ip6_datagram_connect(sk, uaddr, addr_len);
262 release_sock(sk);
263 return res;
264}
265EXPORT_SYMBOL_GPL(ip6_datagram_connect);
266
267int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *uaddr,
268 int addr_len)
269{
270 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, uaddr);
271 if (sin6->sin6_family != AF_INET6)
272 return -EAFNOSUPPORT;
273 return ip6_datagram_connect(sk, uaddr, addr_len);
274}
275EXPORT_SYMBOL_GPL(ip6_datagram_connect_v6_only);
276
277void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
278 __be16 port, u32 info, u8 *payload)
279{
280 struct ipv6_pinfo *np = inet6_sk(sk);
281 struct icmp6hdr *icmph = icmp6_hdr(skb);
282 struct sock_exterr_skb *serr;
283
284 if (!np->recverr)
285 return;
286
287 skb = skb_clone(skb, GFP_ATOMIC);
288 if (!skb)
289 return;
290
291 skb->protocol = htons(ETH_P_IPV6);
292
293 serr = SKB_EXT_ERR(skb);
294 serr->ee.ee_errno = err;
295 serr->ee.ee_origin = SO_EE_ORIGIN_ICMP6;
296 serr->ee.ee_type = icmph->icmp6_type;
297 serr->ee.ee_code = icmph->icmp6_code;
298 serr->ee.ee_pad = 0;
299 serr->ee.ee_info = info;
300 serr->ee.ee_data = 0;
301 serr->addr_offset = (u8 *)&(((struct ipv6hdr *)(icmph + 1))->daddr) -
302 skb_network_header(skb);
303 serr->port = port;
304
305 __skb_pull(skb, payload - skb->data);
306 skb_reset_transport_header(skb);
307
308 if (sock_queue_err_skb(sk, skb))
309 kfree_skb(skb);
310}
311
312void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info)
313{
314 const struct ipv6_pinfo *np = inet6_sk(sk);
315 struct sock_exterr_skb *serr;
316 struct ipv6hdr *iph;
317 struct sk_buff *skb;
318
319 if (!np->recverr)
320 return;
321
322 skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
323 if (!skb)
324 return;
325
326 skb->protocol = htons(ETH_P_IPV6);
327
328 skb_put(skb, sizeof(struct ipv6hdr));
329 skb_reset_network_header(skb);
330 iph = ipv6_hdr(skb);
331 iph->daddr = fl6->daddr;
332
333 serr = SKB_EXT_ERR(skb);
334 serr->ee.ee_errno = err;
335 serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
336 serr->ee.ee_type = 0;
337 serr->ee.ee_code = 0;
338 serr->ee.ee_pad = 0;
339 serr->ee.ee_info = info;
340 serr->ee.ee_data = 0;
341 serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
342 serr->port = fl6->fl6_dport;
343
344 __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
345 skb_reset_transport_header(skb);
346
347 if (sock_queue_err_skb(sk, skb))
348 kfree_skb(skb);
349}
350
351void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu)
352{
353 struct ipv6_pinfo *np = inet6_sk(sk);
354 struct ipv6hdr *iph;
355 struct sk_buff *skb;
356 struct ip6_mtuinfo *mtu_info;
357
358 if (!np->rxopt.bits.rxpmtu)
359 return;
360
361 skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
362 if (!skb)
363 return;
364
365 skb_put(skb, sizeof(struct ipv6hdr));
366 skb_reset_network_header(skb);
367 iph = ipv6_hdr(skb);
368 iph->daddr = fl6->daddr;
369
370 mtu_info = IP6CBMTU(skb);
371
372 mtu_info->ip6m_mtu = mtu;
373 mtu_info->ip6m_addr.sin6_family = AF_INET6;
374 mtu_info->ip6m_addr.sin6_port = 0;
375 mtu_info->ip6m_addr.sin6_flowinfo = 0;
376 mtu_info->ip6m_addr.sin6_scope_id = fl6->flowi6_oif;
377 mtu_info->ip6m_addr.sin6_addr = ipv6_hdr(skb)->daddr;
378
379 __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
380 skb_reset_transport_header(skb);
381
382 skb = xchg(&np->rxpmtu, skb);
383 kfree_skb(skb);
384}
385
386/* For some errors we have valid addr_offset even with zero payload and
387 * zero port. Also, addr_offset should be supported if port is set.
388 */
389static inline bool ipv6_datagram_support_addr(struct sock_exterr_skb *serr)
390{
391 return serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6 ||
392 serr->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
393 serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL || serr->port;
394}
395
396/* IPv6 supports cmsg on all origins aside from SO_EE_ORIGIN_LOCAL.
397 *
398 * At one point, excluding local errors was a quick test to identify icmp/icmp6
399 * errors. This is no longer true, but the test remained, so the v6 stack,
400 * unlike v4, also honors cmsg requests on all wifi and timestamp errors.
401 *
402 * Timestamp code paths do not initialize the fields expected by cmsg:
403 * the PKTINFO fields in skb->cb[]. Fill those in here.
404 */
405static bool ip6_datagram_support_cmsg(struct sk_buff *skb,
406 struct sock_exterr_skb *serr)
407{
408 if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
409 serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6)
410 return true;
411
412 if (serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL)
413 return false;
414
415 if (!skb->dev)
416 return false;
417
418 if (skb->protocol == htons(ETH_P_IPV6))
419 IP6CB(skb)->iif = skb->dev->ifindex;
420 else
421 PKTINFO_SKB_CB(skb)->ipi_ifindex = skb->dev->ifindex;
422
423 return true;
424}
425
426/*
427 * Handle MSG_ERRQUEUE
428 */
429int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
430{
431 struct ipv6_pinfo *np = inet6_sk(sk);
432 struct sock_exterr_skb *serr;
433 struct sk_buff *skb;
434 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name);
435 struct {
436 struct sock_extended_err ee;
437 struct sockaddr_in6 offender;
438 } errhdr;
439 int err;
440 int copied;
441
442 err = -EAGAIN;
443 skb = sock_dequeue_err_skb(sk);
444 if (!skb)
445 goto out;
446
447 copied = skb->len;
448 if (copied > len) {
449 msg->msg_flags |= MSG_TRUNC;
450 copied = len;
451 }
452 err = skb_copy_datagram_msg(skb, 0, msg, copied);
453 if (err)
454 goto out_free_skb;
455
456 sock_recv_timestamp(msg, sk, skb);
457
458 serr = SKB_EXT_ERR(skb);
459
460 if (sin && ipv6_datagram_support_addr(serr)) {
461 const unsigned char *nh = skb_network_header(skb);
462 sin->sin6_family = AF_INET6;
463 sin->sin6_flowinfo = 0;
464 sin->sin6_port = serr->port;
465 if (skb->protocol == htons(ETH_P_IPV6)) {
466 const struct ipv6hdr *ip6h = container_of((struct in6_addr *)(nh + serr->addr_offset),
467 struct ipv6hdr, daddr);
468 sin->sin6_addr = ip6h->daddr;
469 if (np->sndflow)
470 sin->sin6_flowinfo = ip6_flowinfo(ip6h);
471 sin->sin6_scope_id =
472 ipv6_iface_scope_id(&sin->sin6_addr,
473 IP6CB(skb)->iif);
474 } else {
475 ipv6_addr_set_v4mapped(*(__be32 *)(nh + serr->addr_offset),
476 &sin->sin6_addr);
477 sin->sin6_scope_id = 0;
478 }
479 *addr_len = sizeof(*sin);
480 }
481
482 memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
483 sin = &errhdr.offender;
484 memset(sin, 0, sizeof(*sin));
485
486 if (ip6_datagram_support_cmsg(skb, serr)) {
487 sin->sin6_family = AF_INET6;
488 if (np->rxopt.all)
489 ip6_datagram_recv_common_ctl(sk, msg, skb);
490 if (skb->protocol == htons(ETH_P_IPV6)) {
491 sin->sin6_addr = ipv6_hdr(skb)->saddr;
492 if (np->rxopt.all)
493 ip6_datagram_recv_specific_ctl(sk, msg, skb);
494 sin->sin6_scope_id =
495 ipv6_iface_scope_id(&sin->sin6_addr,
496 IP6CB(skb)->iif);
497 } else {
498 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
499 &sin->sin6_addr);
500 if (inet_sk(sk)->cmsg_flags)
501 ip_cmsg_recv(msg, skb);
502 }
503 }
504
505 put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr);
506
507 /* Now we could try to dump offended packet options */
508
509 msg->msg_flags |= MSG_ERRQUEUE;
510 err = copied;
511
512out_free_skb:
513 kfree_skb(skb);
514out:
515 return err;
516}
517EXPORT_SYMBOL_GPL(ipv6_recv_error);
518
519/*
520 * Handle IPV6_RECVPATHMTU
521 */
522int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len,
523 int *addr_len)
524{
525 struct ipv6_pinfo *np = inet6_sk(sk);
526 struct sk_buff *skb;
527 struct ip6_mtuinfo mtu_info;
528 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name);
529 int err;
530 int copied;
531
532 err = -EAGAIN;
533 skb = xchg(&np->rxpmtu, NULL);
534 if (!skb)
535 goto out;
536
537 copied = skb->len;
538 if (copied > len) {
539 msg->msg_flags |= MSG_TRUNC;
540 copied = len;
541 }
542 err = skb_copy_datagram_msg(skb, 0, msg, copied);
543 if (err)
544 goto out_free_skb;
545
546 sock_recv_timestamp(msg, sk, skb);
547
548 memcpy(&mtu_info, IP6CBMTU(skb), sizeof(mtu_info));
549
550 if (sin) {
551 sin->sin6_family = AF_INET6;
552 sin->sin6_flowinfo = 0;
553 sin->sin6_port = 0;
554 sin->sin6_scope_id = mtu_info.ip6m_addr.sin6_scope_id;
555 sin->sin6_addr = mtu_info.ip6m_addr.sin6_addr;
556 *addr_len = sizeof(*sin);
557 }
558
559 put_cmsg(msg, SOL_IPV6, IPV6_PATHMTU, sizeof(mtu_info), &mtu_info);
560
561 err = copied;
562
563out_free_skb:
564 kfree_skb(skb);
565out:
566 return err;
567}
568
569
570void ip6_datagram_recv_common_ctl(struct sock *sk, struct msghdr *msg,
571 struct sk_buff *skb)
572{
573 struct ipv6_pinfo *np = inet6_sk(sk);
574 bool is_ipv6 = skb->protocol == htons(ETH_P_IPV6);
575
576 if (np->rxopt.bits.rxinfo) {
577 struct in6_pktinfo src_info;
578
579 if (is_ipv6) {
580 src_info.ipi6_ifindex = IP6CB(skb)->iif;
581 src_info.ipi6_addr = ipv6_hdr(skb)->daddr;
582 } else {
583 src_info.ipi6_ifindex =
584 PKTINFO_SKB_CB(skb)->ipi_ifindex;
585 ipv6_addr_set_v4mapped(ip_hdr(skb)->daddr,
586 &src_info.ipi6_addr);
587 }
588
589 if (src_info.ipi6_ifindex >= 0)
590 put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO,
591 sizeof(src_info), &src_info);
592 }
593}
594
595void ip6_datagram_recv_specific_ctl(struct sock *sk, struct msghdr *msg,
596 struct sk_buff *skb)
597{
598 struct ipv6_pinfo *np = inet6_sk(sk);
599 struct inet6_skb_parm *opt = IP6CB(skb);
600 unsigned char *nh = skb_network_header(skb);
601
602 if (np->rxopt.bits.rxhlim) {
603 int hlim = ipv6_hdr(skb)->hop_limit;
604 put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
605 }
606
607 if (np->rxopt.bits.rxtclass) {
608 int tclass = ipv6_get_dsfield(ipv6_hdr(skb));
609 put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
610 }
611
612 if (np->rxopt.bits.rxflow) {
613 __be32 flowinfo = ip6_flowinfo((struct ipv6hdr *)nh);
614 if (flowinfo)
615 put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
616 }
617
618 /* HbH is allowed only once */
619 if (np->rxopt.bits.hopopts && (opt->flags & IP6SKB_HOPBYHOP)) {
620 u8 *ptr = nh + sizeof(struct ipv6hdr);
621 put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr);
622 }
623
624 if (opt->lastopt &&
625 (np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) {
626 /*
627 * Silly enough, but we need to reparse in order to
628 * report extension headers (except for HbH)
629 * in order.
630 *
631 * Also note that IPV6_RECVRTHDRDSTOPTS is NOT
632 * (and WILL NOT be) defined because
633 * IPV6_RECVDSTOPTS is more generic. --yoshfuji
634 */
635 unsigned int off = sizeof(struct ipv6hdr);
636 u8 nexthdr = ipv6_hdr(skb)->nexthdr;
637
638 while (off <= opt->lastopt) {
639 unsigned int len;
640 u8 *ptr = nh + off;
641
642 switch (nexthdr) {
643 case IPPROTO_DSTOPTS:
644 nexthdr = ptr[0];
645 len = (ptr[1] + 1) << 3;
646 if (np->rxopt.bits.dstopts)
647 put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, ptr);
648 break;
649 case IPPROTO_ROUTING:
650 nexthdr = ptr[0];
651 len = (ptr[1] + 1) << 3;
652 if (np->rxopt.bits.srcrt)
653 put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, ptr);
654 break;
655 case IPPROTO_AH:
656 nexthdr = ptr[0];
657 len = (ptr[1] + 2) << 2;
658 break;
659 default:
660 nexthdr = ptr[0];
661 len = (ptr[1] + 1) << 3;
662 break;
663 }
664
665 off += len;
666 }
667 }
668
669 /* socket options in old style */
670 if (np->rxopt.bits.rxoinfo) {
671 struct in6_pktinfo src_info;
672
673 src_info.ipi6_ifindex = opt->iif;
674 src_info.ipi6_addr = ipv6_hdr(skb)->daddr;
675 put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
676 }
677 if (np->rxopt.bits.rxohlim) {
678 int hlim = ipv6_hdr(skb)->hop_limit;
679 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
680 }
681 if (np->rxopt.bits.ohopopts && (opt->flags & IP6SKB_HOPBYHOP)) {
682 u8 *ptr = nh + sizeof(struct ipv6hdr);
683 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, (ptr[1]+1)<<3, ptr);
684 }
685 if (np->rxopt.bits.odstopts && opt->dst0) {
686 u8 *ptr = nh + opt->dst0;
687 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
688 }
689 if (np->rxopt.bits.osrcrt && opt->srcrt) {
690 struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt);
691 put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, (rthdr->hdrlen+1) << 3, rthdr);
692 }
693 if (np->rxopt.bits.odstopts && opt->dst1) {
694 u8 *ptr = nh + opt->dst1;
695 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
696 }
697 if (np->rxopt.bits.rxorigdstaddr) {
698 struct sockaddr_in6 sin6;
699 __be16 *ports = (__be16 *) skb_transport_header(skb);
700
701 if (skb_transport_offset(skb) + 4 <= skb->len) {
702 /* All current transport protocols have the port numbers in the
703 * first four bytes of the transport header and this function is
704 * written with this assumption in mind.
705 */
706
707 sin6.sin6_family = AF_INET6;
708 sin6.sin6_addr = ipv6_hdr(skb)->daddr;
709 sin6.sin6_port = ports[1];
710 sin6.sin6_flowinfo = 0;
711 sin6.sin6_scope_id =
712 ipv6_iface_scope_id(&ipv6_hdr(skb)->daddr,
713 opt->iif);
714
715 put_cmsg(msg, SOL_IPV6, IPV6_ORIGDSTADDR, sizeof(sin6), &sin6);
716 }
717 }
718}
719
720void ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg,
721 struct sk_buff *skb)
722{
723 ip6_datagram_recv_common_ctl(sk, msg, skb);
724 ip6_datagram_recv_specific_ctl(sk, msg, skb);
725}
726EXPORT_SYMBOL_GPL(ip6_datagram_recv_ctl);
727
728int ip6_datagram_send_ctl(struct net *net, struct sock *sk,
729 struct msghdr *msg, struct flowi6 *fl6,
730 struct ipv6_txoptions *opt,
731 int *hlimit, int *tclass, int *dontfrag)
732{
733 struct in6_pktinfo *src_info;
734 struct cmsghdr *cmsg;
735 struct ipv6_rt_hdr *rthdr;
736 struct ipv6_opt_hdr *hdr;
737 int len;
738 int err = 0;
739
740 for_each_cmsghdr(cmsg, msg) {
741 int addr_type;
742
743 if (!CMSG_OK(msg, cmsg)) {
744 err = -EINVAL;
745 goto exit_f;
746 }
747
748 if (cmsg->cmsg_level != SOL_IPV6)
749 continue;
750
751 switch (cmsg->cmsg_type) {
752 case IPV6_PKTINFO:
753 case IPV6_2292PKTINFO:
754 {
755 struct net_device *dev = NULL;
756
757 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) {
758 err = -EINVAL;
759 goto exit_f;
760 }
761
762 src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
763
764 if (src_info->ipi6_ifindex) {
765 if (fl6->flowi6_oif &&
766 src_info->ipi6_ifindex != fl6->flowi6_oif)
767 return -EINVAL;
768 fl6->flowi6_oif = src_info->ipi6_ifindex;
769 }
770
771 addr_type = __ipv6_addr_type(&src_info->ipi6_addr);
772
773 rcu_read_lock();
774 if (fl6->flowi6_oif) {
775 dev = dev_get_by_index_rcu(net, fl6->flowi6_oif);
776 if (!dev) {
777 rcu_read_unlock();
778 return -ENODEV;
779 }
780 } else if (addr_type & IPV6_ADDR_LINKLOCAL) {
781 rcu_read_unlock();
782 return -EINVAL;
783 }
784
785 if (addr_type != IPV6_ADDR_ANY) {
786 int strict = __ipv6_addr_src_scope(addr_type) <= IPV6_ADDR_SCOPE_LINKLOCAL;
787 if (!(inet_sk(sk)->freebind || inet_sk(sk)->transparent) &&
788 !ipv6_chk_addr(net, &src_info->ipi6_addr,
789 strict ? dev : NULL, 0) &&
790 !ipv6_chk_acast_addr_src(net, dev,
791 &src_info->ipi6_addr))
792 err = -EINVAL;
793 else
794 fl6->saddr = src_info->ipi6_addr;
795 }
796
797 rcu_read_unlock();
798
799 if (err)
800 goto exit_f;
801
802 break;
803 }
804
805 case IPV6_FLOWINFO:
806 if (cmsg->cmsg_len < CMSG_LEN(4)) {
807 err = -EINVAL;
808 goto exit_f;
809 }
810
811 if (fl6->flowlabel&IPV6_FLOWINFO_MASK) {
812 if ((fl6->flowlabel^*(__be32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) {
813 err = -EINVAL;
814 goto exit_f;
815 }
816 }
817 fl6->flowlabel = IPV6_FLOWINFO_MASK & *(__be32 *)CMSG_DATA(cmsg);
818 break;
819
820 case IPV6_2292HOPOPTS:
821 case IPV6_HOPOPTS:
822 if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
823 err = -EINVAL;
824 goto exit_f;
825 }
826
827 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
828 len = ((hdr->hdrlen + 1) << 3);
829 if (cmsg->cmsg_len < CMSG_LEN(len)) {
830 err = -EINVAL;
831 goto exit_f;
832 }
833 if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
834 err = -EPERM;
835 goto exit_f;
836 }
837 opt->opt_nflen += len;
838 opt->hopopt = hdr;
839 break;
840
841 case IPV6_2292DSTOPTS:
842 if (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 if (opt->dst1opt) {
858 err = -EINVAL;
859 goto exit_f;
860 }
861 opt->opt_flen += len;
862 opt->dst1opt = hdr;
863 break;
864
865 case IPV6_DSTOPTS:
866 case IPV6_RTHDRDSTOPTS:
867 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
868 err = -EINVAL;
869 goto exit_f;
870 }
871
872 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
873 len = ((hdr->hdrlen + 1) << 3);
874 if (cmsg->cmsg_len < CMSG_LEN(len)) {
875 err = -EINVAL;
876 goto exit_f;
877 }
878 if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
879 err = -EPERM;
880 goto exit_f;
881 }
882 if (cmsg->cmsg_type == IPV6_DSTOPTS) {
883 opt->opt_flen += len;
884 opt->dst1opt = hdr;
885 } else {
886 opt->opt_nflen += len;
887 opt->dst0opt = hdr;
888 }
889 break;
890
891 case IPV6_2292RTHDR:
892 case IPV6_RTHDR:
893 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) {
894 err = -EINVAL;
895 goto exit_f;
896 }
897
898 rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg);
899
900 switch (rthdr->type) {
901#if IS_ENABLED(CONFIG_IPV6_MIP6)
902 case IPV6_SRCRT_TYPE_2:
903 if (rthdr->hdrlen != 2 ||
904 rthdr->segments_left != 1) {
905 err = -EINVAL;
906 goto exit_f;
907 }
908 break;
909#endif
910 default:
911 err = -EINVAL;
912 goto exit_f;
913 }
914
915 len = ((rthdr->hdrlen + 1) << 3);
916
917 if (cmsg->cmsg_len < CMSG_LEN(len)) {
918 err = -EINVAL;
919 goto exit_f;
920 }
921
922 /* segments left must also match */
923 if ((rthdr->hdrlen >> 1) != rthdr->segments_left) {
924 err = -EINVAL;
925 goto exit_f;
926 }
927
928 opt->opt_nflen += len;
929 opt->srcrt = rthdr;
930
931 if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) {
932 int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3);
933
934 opt->opt_nflen += dsthdrlen;
935 opt->dst0opt = opt->dst1opt;
936 opt->dst1opt = NULL;
937 opt->opt_flen -= dsthdrlen;
938 }
939
940 break;
941
942 case IPV6_2292HOPLIMIT:
943 case IPV6_HOPLIMIT:
944 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
945 err = -EINVAL;
946 goto exit_f;
947 }
948
949 *hlimit = *(int *)CMSG_DATA(cmsg);
950 if (*hlimit < -1 || *hlimit > 0xff) {
951 err = -EINVAL;
952 goto exit_f;
953 }
954
955 break;
956
957 case IPV6_TCLASS:
958 {
959 int tc;
960
961 err = -EINVAL;
962 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
963 goto exit_f;
964
965 tc = *(int *)CMSG_DATA(cmsg);
966 if (tc < -1 || tc > 0xff)
967 goto exit_f;
968
969 err = 0;
970 *tclass = tc;
971
972 break;
973 }
974
975 case IPV6_DONTFRAG:
976 {
977 int df;
978
979 err = -EINVAL;
980 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
981 goto exit_f;
982
983 df = *(int *)CMSG_DATA(cmsg);
984 if (df < 0 || df > 1)
985 goto exit_f;
986
987 err = 0;
988 *dontfrag = df;
989
990 break;
991 }
992 default:
993 net_dbg_ratelimited("invalid cmsg type: %d\n",
994 cmsg->cmsg_type);
995 err = -EINVAL;
996 goto exit_f;
997 }
998 }
999
1000exit_f:
1001 return err;
1002}
1003EXPORT_SYMBOL_GPL(ip6_datagram_send_ctl);
1004
1005void ip6_dgram_sock_seq_show(struct seq_file *seq, struct sock *sp,
1006 __u16 srcp, __u16 destp, int bucket)
1007{
1008 const struct in6_addr *dest, *src;
1009
1010 dest = &sp->sk_v6_daddr;
1011 src = &sp->sk_v6_rcv_saddr;
1012 seq_printf(seq,
1013 "%5d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1014 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %d\n",
1015 bucket,
1016 src->s6_addr32[0], src->s6_addr32[1],
1017 src->s6_addr32[2], src->s6_addr32[3], srcp,
1018 dest->s6_addr32[0], dest->s6_addr32[1],
1019 dest->s6_addr32[2], dest->s6_addr32[3], destp,
1020 sp->sk_state,
1021 sk_wmem_alloc_get(sp),
1022 sk_rmem_alloc_get(sp),
1023 0, 0L, 0,
1024 from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)),
1025 0,
1026 sock_i_ino(sp),
1027 atomic_read(&sp->sk_refcnt), sp,
1028 atomic_read(&sp->sk_drops));
1029}
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
26#include <net/ipv6.h>
27#include <net/ndisc.h>
28#include <net/addrconf.h>
29#include <net/transp_v6.h>
30#include <net/ip6_route.h>
31#include <net/tcp_states.h>
32
33#include <linux/errqueue.h>
34#include <asm/uaccess.h>
35
36static inline int ipv6_mapped_addr_any(const struct in6_addr *a)
37{
38 return (ipv6_addr_v4mapped(a) && (a->s6_addr32[3] == 0));
39}
40
41int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
42{
43 struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr;
44 struct inet_sock *inet = inet_sk(sk);
45 struct ipv6_pinfo *np = inet6_sk(sk);
46 struct in6_addr *daddr, *final_p, final;
47 struct dst_entry *dst;
48 struct flowi6 fl6;
49 struct ip6_flowlabel *flowlabel = NULL;
50 struct ipv6_txoptions *opt;
51 int addr_type;
52 int err;
53
54 if (usin->sin6_family == AF_INET) {
55 if (__ipv6_only_sock(sk))
56 return -EAFNOSUPPORT;
57 err = ip4_datagram_connect(sk, uaddr, addr_len);
58 goto ipv4_connected;
59 }
60
61 if (addr_len < SIN6_LEN_RFC2133)
62 return -EINVAL;
63
64 if (usin->sin6_family != AF_INET6)
65 return -EAFNOSUPPORT;
66
67 memset(&fl6, 0, sizeof(fl6));
68 if (np->sndflow) {
69 fl6.flowlabel = usin->sin6_flowinfo&IPV6_FLOWINFO_MASK;
70 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
71 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
72 if (flowlabel == NULL)
73 return -EINVAL;
74 ipv6_addr_copy(&usin->sin6_addr, &flowlabel->dst);
75 }
76 }
77
78 addr_type = ipv6_addr_type(&usin->sin6_addr);
79
80 if (addr_type == IPV6_ADDR_ANY) {
81 /*
82 * connect to self
83 */
84 usin->sin6_addr.s6_addr[15] = 0x01;
85 }
86
87 daddr = &usin->sin6_addr;
88
89 if (addr_type == IPV6_ADDR_MAPPED) {
90 struct sockaddr_in sin;
91
92 if (__ipv6_only_sock(sk)) {
93 err = -ENETUNREACH;
94 goto out;
95 }
96 sin.sin_family = AF_INET;
97 sin.sin_addr.s_addr = daddr->s6_addr32[3];
98 sin.sin_port = usin->sin6_port;
99
100 err = ip4_datagram_connect(sk,
101 (struct sockaddr*) &sin,
102 sizeof(sin));
103
104ipv4_connected:
105 if (err)
106 goto out;
107
108 ipv6_addr_set_v4mapped(inet->inet_daddr, &np->daddr);
109
110 if (ipv6_addr_any(&np->saddr) ||
111 ipv6_mapped_addr_any(&np->saddr))
112 ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr);
113
114 if (ipv6_addr_any(&np->rcv_saddr) ||
115 ipv6_mapped_addr_any(&np->rcv_saddr)) {
116 ipv6_addr_set_v4mapped(inet->inet_rcv_saddr,
117 &np->rcv_saddr);
118 if (sk->sk_prot->rehash)
119 sk->sk_prot->rehash(sk);
120 }
121
122 goto out;
123 }
124
125 if (addr_type&IPV6_ADDR_LINKLOCAL) {
126 if (addr_len >= sizeof(struct sockaddr_in6) &&
127 usin->sin6_scope_id) {
128 if (sk->sk_bound_dev_if &&
129 sk->sk_bound_dev_if != usin->sin6_scope_id) {
130 err = -EINVAL;
131 goto out;
132 }
133 sk->sk_bound_dev_if = usin->sin6_scope_id;
134 }
135
136 if (!sk->sk_bound_dev_if && (addr_type & IPV6_ADDR_MULTICAST))
137 sk->sk_bound_dev_if = np->mcast_oif;
138
139 /* Connect to link-local address requires an interface */
140 if (!sk->sk_bound_dev_if) {
141 err = -EINVAL;
142 goto out;
143 }
144 }
145
146 ipv6_addr_copy(&np->daddr, daddr);
147 np->flow_label = fl6.flowlabel;
148
149 inet->inet_dport = usin->sin6_port;
150
151 /*
152 * Check for a route to destination an obtain the
153 * destination cache for it.
154 */
155
156 fl6.flowi6_proto = sk->sk_protocol;
157 ipv6_addr_copy(&fl6.daddr, &np->daddr);
158 ipv6_addr_copy(&fl6.saddr, &np->saddr);
159 fl6.flowi6_oif = sk->sk_bound_dev_if;
160 fl6.flowi6_mark = sk->sk_mark;
161 fl6.fl6_dport = inet->inet_dport;
162 fl6.fl6_sport = inet->inet_sport;
163
164 if (!fl6.flowi6_oif && (addr_type&IPV6_ADDR_MULTICAST))
165 fl6.flowi6_oif = np->mcast_oif;
166
167 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
168
169 opt = flowlabel ? flowlabel->opt : np->opt;
170 final_p = fl6_update_dst(&fl6, opt, &final);
171
172 dst = ip6_dst_lookup_flow(sk, &fl6, final_p, true);
173 err = 0;
174 if (IS_ERR(dst)) {
175 err = PTR_ERR(dst);
176 goto out;
177 }
178
179 /* source address lookup done in ip6_dst_lookup */
180
181 if (ipv6_addr_any(&np->saddr))
182 ipv6_addr_copy(&np->saddr, &fl6.saddr);
183
184 if (ipv6_addr_any(&np->rcv_saddr)) {
185 ipv6_addr_copy(&np->rcv_saddr, &fl6.saddr);
186 inet->inet_rcv_saddr = LOOPBACK4_IPV6;
187 if (sk->sk_prot->rehash)
188 sk->sk_prot->rehash(sk);
189 }
190
191 ip6_dst_store(sk, dst,
192 ipv6_addr_equal(&fl6.daddr, &np->daddr) ?
193 &np->daddr : NULL,
194#ifdef CONFIG_IPV6_SUBTREES
195 ipv6_addr_equal(&fl6.saddr, &np->saddr) ?
196 &np->saddr :
197#endif
198 NULL);
199
200 sk->sk_state = TCP_ESTABLISHED;
201out:
202 fl6_sock_release(flowlabel);
203 return err;
204}
205
206void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
207 __be16 port, u32 info, u8 *payload)
208{
209 struct ipv6_pinfo *np = inet6_sk(sk);
210 struct icmp6hdr *icmph = icmp6_hdr(skb);
211 struct sock_exterr_skb *serr;
212
213 if (!np->recverr)
214 return;
215
216 skb = skb_clone(skb, GFP_ATOMIC);
217 if (!skb)
218 return;
219
220 skb->protocol = htons(ETH_P_IPV6);
221
222 serr = SKB_EXT_ERR(skb);
223 serr->ee.ee_errno = err;
224 serr->ee.ee_origin = SO_EE_ORIGIN_ICMP6;
225 serr->ee.ee_type = icmph->icmp6_type;
226 serr->ee.ee_code = icmph->icmp6_code;
227 serr->ee.ee_pad = 0;
228 serr->ee.ee_info = info;
229 serr->ee.ee_data = 0;
230 serr->addr_offset = (u8 *)&(((struct ipv6hdr *)(icmph + 1))->daddr) -
231 skb_network_header(skb);
232 serr->port = port;
233
234 __skb_pull(skb, payload - skb->data);
235 skb_reset_transport_header(skb);
236
237 if (sock_queue_err_skb(sk, skb))
238 kfree_skb(skb);
239}
240
241void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info)
242{
243 struct ipv6_pinfo *np = inet6_sk(sk);
244 struct sock_exterr_skb *serr;
245 struct ipv6hdr *iph;
246 struct sk_buff *skb;
247
248 if (!np->recverr)
249 return;
250
251 skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
252 if (!skb)
253 return;
254
255 skb->protocol = htons(ETH_P_IPV6);
256
257 skb_put(skb, sizeof(struct ipv6hdr));
258 skb_reset_network_header(skb);
259 iph = ipv6_hdr(skb);
260 ipv6_addr_copy(&iph->daddr, &fl6->daddr);
261
262 serr = SKB_EXT_ERR(skb);
263 serr->ee.ee_errno = err;
264 serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
265 serr->ee.ee_type = 0;
266 serr->ee.ee_code = 0;
267 serr->ee.ee_pad = 0;
268 serr->ee.ee_info = info;
269 serr->ee.ee_data = 0;
270 serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
271 serr->port = fl6->fl6_dport;
272
273 __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
274 skb_reset_transport_header(skb);
275
276 if (sock_queue_err_skb(sk, skb))
277 kfree_skb(skb);
278}
279
280void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu)
281{
282 struct ipv6_pinfo *np = inet6_sk(sk);
283 struct ipv6hdr *iph;
284 struct sk_buff *skb;
285 struct ip6_mtuinfo *mtu_info;
286
287 if (!np->rxopt.bits.rxpmtu)
288 return;
289
290 skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
291 if (!skb)
292 return;
293
294 skb_put(skb, sizeof(struct ipv6hdr));
295 skb_reset_network_header(skb);
296 iph = ipv6_hdr(skb);
297 ipv6_addr_copy(&iph->daddr, &fl6->daddr);
298
299 mtu_info = IP6CBMTU(skb);
300 if (!mtu_info) {
301 kfree_skb(skb);
302 return;
303 }
304
305 mtu_info->ip6m_mtu = mtu;
306 mtu_info->ip6m_addr.sin6_family = AF_INET6;
307 mtu_info->ip6m_addr.sin6_port = 0;
308 mtu_info->ip6m_addr.sin6_flowinfo = 0;
309 mtu_info->ip6m_addr.sin6_scope_id = fl6->flowi6_oif;
310 ipv6_addr_copy(&mtu_info->ip6m_addr.sin6_addr, &ipv6_hdr(skb)->daddr);
311
312 __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
313 skb_reset_transport_header(skb);
314
315 skb = xchg(&np->rxpmtu, skb);
316 kfree_skb(skb);
317}
318
319/*
320 * Handle MSG_ERRQUEUE
321 */
322int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len)
323{
324 struct ipv6_pinfo *np = inet6_sk(sk);
325 struct sock_exterr_skb *serr;
326 struct sk_buff *skb, *skb2;
327 struct sockaddr_in6 *sin;
328 struct {
329 struct sock_extended_err ee;
330 struct sockaddr_in6 offender;
331 } errhdr;
332 int err;
333 int copied;
334
335 err = -EAGAIN;
336 skb = skb_dequeue(&sk->sk_error_queue);
337 if (skb == NULL)
338 goto out;
339
340 copied = skb->len;
341 if (copied > len) {
342 msg->msg_flags |= MSG_TRUNC;
343 copied = len;
344 }
345 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
346 if (err)
347 goto out_free_skb;
348
349 sock_recv_timestamp(msg, sk, skb);
350
351 serr = SKB_EXT_ERR(skb);
352
353 sin = (struct sockaddr_in6 *)msg->msg_name;
354 if (sin) {
355 const unsigned char *nh = skb_network_header(skb);
356 sin->sin6_family = AF_INET6;
357 sin->sin6_flowinfo = 0;
358 sin->sin6_port = serr->port;
359 sin->sin6_scope_id = 0;
360 if (skb->protocol == htons(ETH_P_IPV6)) {
361 ipv6_addr_copy(&sin->sin6_addr,
362 (struct in6_addr *)(nh + serr->addr_offset));
363 if (np->sndflow)
364 sin->sin6_flowinfo =
365 (*(__be32 *)(nh + serr->addr_offset - 24) &
366 IPV6_FLOWINFO_MASK);
367 if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
368 sin->sin6_scope_id = IP6CB(skb)->iif;
369 } else {
370 ipv6_addr_set_v4mapped(*(__be32 *)(nh + serr->addr_offset),
371 &sin->sin6_addr);
372 }
373 }
374
375 memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
376 sin = &errhdr.offender;
377 sin->sin6_family = AF_UNSPEC;
378 if (serr->ee.ee_origin != SO_EE_ORIGIN_LOCAL) {
379 sin->sin6_family = AF_INET6;
380 sin->sin6_flowinfo = 0;
381 sin->sin6_scope_id = 0;
382 if (skb->protocol == htons(ETH_P_IPV6)) {
383 ipv6_addr_copy(&sin->sin6_addr, &ipv6_hdr(skb)->saddr);
384 if (np->rxopt.all)
385 datagram_recv_ctl(sk, msg, skb);
386 if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
387 sin->sin6_scope_id = IP6CB(skb)->iif;
388 } else {
389 struct inet_sock *inet = inet_sk(sk);
390
391 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
392 &sin->sin6_addr);
393 if (inet->cmsg_flags)
394 ip_cmsg_recv(msg, skb);
395 }
396 }
397
398 put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr);
399
400 /* Now we could try to dump offended packet options */
401
402 msg->msg_flags |= MSG_ERRQUEUE;
403 err = copied;
404
405 /* Reset and regenerate socket error */
406 spin_lock_bh(&sk->sk_error_queue.lock);
407 sk->sk_err = 0;
408 if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
409 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
410 spin_unlock_bh(&sk->sk_error_queue.lock);
411 sk->sk_error_report(sk);
412 } else {
413 spin_unlock_bh(&sk->sk_error_queue.lock);
414 }
415
416out_free_skb:
417 kfree_skb(skb);
418out:
419 return err;
420}
421
422/*
423 * Handle IPV6_RECVPATHMTU
424 */
425int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len)
426{
427 struct ipv6_pinfo *np = inet6_sk(sk);
428 struct sk_buff *skb;
429 struct sockaddr_in6 *sin;
430 struct ip6_mtuinfo mtu_info;
431 int err;
432 int copied;
433
434 err = -EAGAIN;
435 skb = xchg(&np->rxpmtu, NULL);
436 if (skb == NULL)
437 goto out;
438
439 copied = skb->len;
440 if (copied > len) {
441 msg->msg_flags |= MSG_TRUNC;
442 copied = len;
443 }
444 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
445 if (err)
446 goto out_free_skb;
447
448 sock_recv_timestamp(msg, sk, skb);
449
450 memcpy(&mtu_info, IP6CBMTU(skb), sizeof(mtu_info));
451
452 sin = (struct sockaddr_in6 *)msg->msg_name;
453 if (sin) {
454 sin->sin6_family = AF_INET6;
455 sin->sin6_flowinfo = 0;
456 sin->sin6_port = 0;
457 sin->sin6_scope_id = mtu_info.ip6m_addr.sin6_scope_id;
458 ipv6_addr_copy(&sin->sin6_addr, &mtu_info.ip6m_addr.sin6_addr);
459 }
460
461 put_cmsg(msg, SOL_IPV6, IPV6_PATHMTU, sizeof(mtu_info), &mtu_info);
462
463 err = copied;
464
465out_free_skb:
466 kfree_skb(skb);
467out:
468 return err;
469}
470
471
472int datagram_recv_ctl(struct sock *sk, struct msghdr *msg, struct sk_buff *skb)
473{
474 struct ipv6_pinfo *np = inet6_sk(sk);
475 struct inet6_skb_parm *opt = IP6CB(skb);
476 unsigned char *nh = skb_network_header(skb);
477
478 if (np->rxopt.bits.rxinfo) {
479 struct in6_pktinfo src_info;
480
481 src_info.ipi6_ifindex = opt->iif;
482 ipv6_addr_copy(&src_info.ipi6_addr, &ipv6_hdr(skb)->daddr);
483 put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
484 }
485
486 if (np->rxopt.bits.rxhlim) {
487 int hlim = ipv6_hdr(skb)->hop_limit;
488 put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
489 }
490
491 if (np->rxopt.bits.rxtclass) {
492 int tclass = (ntohl(*(__be32 *)ipv6_hdr(skb)) >> 20) & 0xff;
493 put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
494 }
495
496 if (np->rxopt.bits.rxflow && (*(__be32 *)nh & IPV6_FLOWINFO_MASK)) {
497 __be32 flowinfo = *(__be32 *)nh & IPV6_FLOWINFO_MASK;
498 put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
499 }
500
501 /* HbH is allowed only once */
502 if (np->rxopt.bits.hopopts && opt->hop) {
503 u8 *ptr = nh + opt->hop;
504 put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr);
505 }
506
507 if (opt->lastopt &&
508 (np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) {
509 /*
510 * Silly enough, but we need to reparse in order to
511 * report extension headers (except for HbH)
512 * in order.
513 *
514 * Also note that IPV6_RECVRTHDRDSTOPTS is NOT
515 * (and WILL NOT be) defined because
516 * IPV6_RECVDSTOPTS is more generic. --yoshfuji
517 */
518 unsigned int off = sizeof(struct ipv6hdr);
519 u8 nexthdr = ipv6_hdr(skb)->nexthdr;
520
521 while (off <= opt->lastopt) {
522 unsigned len;
523 u8 *ptr = nh + off;
524
525 switch(nexthdr) {
526 case IPPROTO_DSTOPTS:
527 nexthdr = ptr[0];
528 len = (ptr[1] + 1) << 3;
529 if (np->rxopt.bits.dstopts)
530 put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, ptr);
531 break;
532 case IPPROTO_ROUTING:
533 nexthdr = ptr[0];
534 len = (ptr[1] + 1) << 3;
535 if (np->rxopt.bits.srcrt)
536 put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, ptr);
537 break;
538 case IPPROTO_AH:
539 nexthdr = ptr[0];
540 len = (ptr[1] + 2) << 2;
541 break;
542 default:
543 nexthdr = ptr[0];
544 len = (ptr[1] + 1) << 3;
545 break;
546 }
547
548 off += len;
549 }
550 }
551
552 /* socket options in old style */
553 if (np->rxopt.bits.rxoinfo) {
554 struct in6_pktinfo src_info;
555
556 src_info.ipi6_ifindex = opt->iif;
557 ipv6_addr_copy(&src_info.ipi6_addr, &ipv6_hdr(skb)->daddr);
558 put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
559 }
560 if (np->rxopt.bits.rxohlim) {
561 int hlim = ipv6_hdr(skb)->hop_limit;
562 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
563 }
564 if (np->rxopt.bits.ohopopts && opt->hop) {
565 u8 *ptr = nh + opt->hop;
566 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, (ptr[1]+1)<<3, ptr);
567 }
568 if (np->rxopt.bits.odstopts && opt->dst0) {
569 u8 *ptr = nh + opt->dst0;
570 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
571 }
572 if (np->rxopt.bits.osrcrt && opt->srcrt) {
573 struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt);
574 put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, (rthdr->hdrlen+1) << 3, rthdr);
575 }
576 if (np->rxopt.bits.odstopts && opt->dst1) {
577 u8 *ptr = nh + opt->dst1;
578 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
579 }
580 if (np->rxopt.bits.rxorigdstaddr) {
581 struct sockaddr_in6 sin6;
582 u16 *ports = (u16 *) skb_transport_header(skb);
583
584 if (skb_transport_offset(skb) + 4 <= skb->len) {
585 /* All current transport protocols have the port numbers in the
586 * first four bytes of the transport header and this function is
587 * written with this assumption in mind.
588 */
589
590 sin6.sin6_family = AF_INET6;
591 ipv6_addr_copy(&sin6.sin6_addr, &ipv6_hdr(skb)->daddr);
592 sin6.sin6_port = ports[1];
593 sin6.sin6_flowinfo = 0;
594 sin6.sin6_scope_id = 0;
595
596 put_cmsg(msg, SOL_IPV6, IPV6_ORIGDSTADDR, sizeof(sin6), &sin6);
597 }
598 }
599 return 0;
600}
601
602int datagram_send_ctl(struct net *net, struct sock *sk,
603 struct msghdr *msg, struct flowi6 *fl6,
604 struct ipv6_txoptions *opt,
605 int *hlimit, int *tclass, int *dontfrag)
606{
607 struct in6_pktinfo *src_info;
608 struct cmsghdr *cmsg;
609 struct ipv6_rt_hdr *rthdr;
610 struct ipv6_opt_hdr *hdr;
611 int len;
612 int err = 0;
613
614 for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
615 int addr_type;
616
617 if (!CMSG_OK(msg, cmsg)) {
618 err = -EINVAL;
619 goto exit_f;
620 }
621
622 if (cmsg->cmsg_level != SOL_IPV6)
623 continue;
624
625 switch (cmsg->cmsg_type) {
626 case IPV6_PKTINFO:
627 case IPV6_2292PKTINFO:
628 {
629 struct net_device *dev = NULL;
630
631 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) {
632 err = -EINVAL;
633 goto exit_f;
634 }
635
636 src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
637
638 if (src_info->ipi6_ifindex) {
639 if (fl6->flowi6_oif &&
640 src_info->ipi6_ifindex != fl6->flowi6_oif)
641 return -EINVAL;
642 fl6->flowi6_oif = src_info->ipi6_ifindex;
643 }
644
645 addr_type = __ipv6_addr_type(&src_info->ipi6_addr);
646
647 rcu_read_lock();
648 if (fl6->flowi6_oif) {
649 dev = dev_get_by_index_rcu(net, fl6->flowi6_oif);
650 if (!dev) {
651 rcu_read_unlock();
652 return -ENODEV;
653 }
654 } else if (addr_type & IPV6_ADDR_LINKLOCAL) {
655 rcu_read_unlock();
656 return -EINVAL;
657 }
658
659 if (addr_type != IPV6_ADDR_ANY) {
660 int strict = __ipv6_addr_src_scope(addr_type) <= IPV6_ADDR_SCOPE_LINKLOCAL;
661 if (!inet_sk(sk)->transparent &&
662 !ipv6_chk_addr(net, &src_info->ipi6_addr,
663 strict ? dev : NULL, 0))
664 err = -EINVAL;
665 else
666 ipv6_addr_copy(&fl6->saddr, &src_info->ipi6_addr);
667 }
668
669 rcu_read_unlock();
670
671 if (err)
672 goto exit_f;
673
674 break;
675 }
676
677 case IPV6_FLOWINFO:
678 if (cmsg->cmsg_len < CMSG_LEN(4)) {
679 err = -EINVAL;
680 goto exit_f;
681 }
682
683 if (fl6->flowlabel&IPV6_FLOWINFO_MASK) {
684 if ((fl6->flowlabel^*(__be32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) {
685 err = -EINVAL;
686 goto exit_f;
687 }
688 }
689 fl6->flowlabel = IPV6_FLOWINFO_MASK & *(__be32 *)CMSG_DATA(cmsg);
690 break;
691
692 case IPV6_2292HOPOPTS:
693 case IPV6_HOPOPTS:
694 if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
695 err = -EINVAL;
696 goto exit_f;
697 }
698
699 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
700 len = ((hdr->hdrlen + 1) << 3);
701 if (cmsg->cmsg_len < CMSG_LEN(len)) {
702 err = -EINVAL;
703 goto exit_f;
704 }
705 if (!capable(CAP_NET_RAW)) {
706 err = -EPERM;
707 goto exit_f;
708 }
709 opt->opt_nflen += len;
710 opt->hopopt = hdr;
711 break;
712
713 case IPV6_2292DSTOPTS:
714 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
715 err = -EINVAL;
716 goto exit_f;
717 }
718
719 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
720 len = ((hdr->hdrlen + 1) << 3);
721 if (cmsg->cmsg_len < CMSG_LEN(len)) {
722 err = -EINVAL;
723 goto exit_f;
724 }
725 if (!capable(CAP_NET_RAW)) {
726 err = -EPERM;
727 goto exit_f;
728 }
729 if (opt->dst1opt) {
730 err = -EINVAL;
731 goto exit_f;
732 }
733 opt->opt_flen += len;
734 opt->dst1opt = hdr;
735 break;
736
737 case IPV6_DSTOPTS:
738 case IPV6_RTHDRDSTOPTS:
739 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
740 err = -EINVAL;
741 goto exit_f;
742 }
743
744 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
745 len = ((hdr->hdrlen + 1) << 3);
746 if (cmsg->cmsg_len < CMSG_LEN(len)) {
747 err = -EINVAL;
748 goto exit_f;
749 }
750 if (!capable(CAP_NET_RAW)) {
751 err = -EPERM;
752 goto exit_f;
753 }
754 if (cmsg->cmsg_type == IPV6_DSTOPTS) {
755 opt->opt_flen += len;
756 opt->dst1opt = hdr;
757 } else {
758 opt->opt_nflen += len;
759 opt->dst0opt = hdr;
760 }
761 break;
762
763 case IPV6_2292RTHDR:
764 case IPV6_RTHDR:
765 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) {
766 err = -EINVAL;
767 goto exit_f;
768 }
769
770 rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg);
771
772 switch (rthdr->type) {
773#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
774 case IPV6_SRCRT_TYPE_2:
775 if (rthdr->hdrlen != 2 ||
776 rthdr->segments_left != 1) {
777 err = -EINVAL;
778 goto exit_f;
779 }
780 break;
781#endif
782 default:
783 err = -EINVAL;
784 goto exit_f;
785 }
786
787 len = ((rthdr->hdrlen + 1) << 3);
788
789 if (cmsg->cmsg_len < CMSG_LEN(len)) {
790 err = -EINVAL;
791 goto exit_f;
792 }
793
794 /* segments left must also match */
795 if ((rthdr->hdrlen >> 1) != rthdr->segments_left) {
796 err = -EINVAL;
797 goto exit_f;
798 }
799
800 opt->opt_nflen += len;
801 opt->srcrt = rthdr;
802
803 if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) {
804 int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3);
805
806 opt->opt_nflen += dsthdrlen;
807 opt->dst0opt = opt->dst1opt;
808 opt->dst1opt = NULL;
809 opt->opt_flen -= dsthdrlen;
810 }
811
812 break;
813
814 case IPV6_2292HOPLIMIT:
815 case IPV6_HOPLIMIT:
816 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
817 err = -EINVAL;
818 goto exit_f;
819 }
820
821 *hlimit = *(int *)CMSG_DATA(cmsg);
822 if (*hlimit < -1 || *hlimit > 0xff) {
823 err = -EINVAL;
824 goto exit_f;
825 }
826
827 break;
828
829 case IPV6_TCLASS:
830 {
831 int tc;
832
833 err = -EINVAL;
834 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
835 goto exit_f;
836 }
837
838 tc = *(int *)CMSG_DATA(cmsg);
839 if (tc < -1 || tc > 0xff)
840 goto exit_f;
841
842 err = 0;
843 *tclass = tc;
844
845 break;
846 }
847
848 case IPV6_DONTFRAG:
849 {
850 int df;
851
852 err = -EINVAL;
853 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
854 goto exit_f;
855 }
856
857 df = *(int *)CMSG_DATA(cmsg);
858 if (df < 0 || df > 1)
859 goto exit_f;
860
861 err = 0;
862 *dontfrag = df;
863
864 break;
865 }
866 default:
867 LIMIT_NETDEBUG(KERN_DEBUG "invalid cmsg type: %d\n",
868 cmsg->cmsg_type);
869 err = -EINVAL;
870 goto exit_f;
871 }
872 }
873
874exit_f:
875 return err;
876}