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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}
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
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 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
68int 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_dst_store(sk, dst,
110 ipv6_addr_equal(&fl6.daddr, &sk->sk_v6_daddr) ?
111 &sk->sk_v6_daddr : NULL,
112#ifdef CONFIG_IPV6_SUBTREES
113 ipv6_addr_equal(&fl6.saddr, &np->saddr) ?
114 &np->saddr :
115#endif
116 NULL);
117
118out:
119 fl6_sock_release(flowlabel);
120 return err;
121}
122
123void ip6_datagram_release_cb(struct sock *sk)
124{
125 struct dst_entry *dst;
126
127 if (ipv6_addr_v4mapped(&sk->sk_v6_daddr))
128 return;
129
130 rcu_read_lock();
131 dst = __sk_dst_get(sk);
132 if (!dst || !dst->obsolete ||
133 dst->ops->check(dst, inet6_sk(sk)->dst_cookie)) {
134 rcu_read_unlock();
135 return;
136 }
137 rcu_read_unlock();
138
139 ip6_datagram_dst_update(sk, false);
140}
141EXPORT_SYMBOL_GPL(ip6_datagram_release_cb);
142
143int __ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr,
144 int addr_len)
145{
146 struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr;
147 struct inet_sock *inet = inet_sk(sk);
148 struct ipv6_pinfo *np = inet6_sk(sk);
149 struct in6_addr *daddr;
150 int addr_type;
151 int err;
152 __be32 fl6_flowlabel = 0;
153
154 if (usin->sin6_family == AF_INET) {
155 if (__ipv6_only_sock(sk))
156 return -EAFNOSUPPORT;
157 err = __ip4_datagram_connect(sk, uaddr, addr_len);
158 goto ipv4_connected;
159 }
160
161 if (addr_len < SIN6_LEN_RFC2133)
162 return -EINVAL;
163
164 if (usin->sin6_family != AF_INET6)
165 return -EAFNOSUPPORT;
166
167 if (np->sndflow)
168 fl6_flowlabel = usin->sin6_flowinfo & IPV6_FLOWINFO_MASK;
169
170 if (ipv6_addr_any(&usin->sin6_addr)) {
171 /*
172 * connect to self
173 */
174 if (ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr))
175 ipv6_addr_set_v4mapped(htonl(INADDR_LOOPBACK),
176 &usin->sin6_addr);
177 else
178 usin->sin6_addr = in6addr_loopback;
179 }
180
181 addr_type = ipv6_addr_type(&usin->sin6_addr);
182
183 daddr = &usin->sin6_addr;
184
185 if (addr_type & IPV6_ADDR_MAPPED) {
186 struct sockaddr_in sin;
187
188 if (__ipv6_only_sock(sk)) {
189 err = -ENETUNREACH;
190 goto out;
191 }
192 sin.sin_family = AF_INET;
193 sin.sin_addr.s_addr = daddr->s6_addr32[3];
194 sin.sin_port = usin->sin6_port;
195
196 err = __ip4_datagram_connect(sk,
197 (struct sockaddr *) &sin,
198 sizeof(sin));
199
200ipv4_connected:
201 if (err)
202 goto out;
203
204 ipv6_addr_set_v4mapped(inet->inet_daddr, &sk->sk_v6_daddr);
205
206 if (ipv6_addr_any(&np->saddr) ||
207 ipv6_mapped_addr_any(&np->saddr))
208 ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr);
209
210 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr) ||
211 ipv6_mapped_addr_any(&sk->sk_v6_rcv_saddr)) {
212 ipv6_addr_set_v4mapped(inet->inet_rcv_saddr,
213 &sk->sk_v6_rcv_saddr);
214 if (sk->sk_prot->rehash)
215 sk->sk_prot->rehash(sk);
216 }
217
218 goto out;
219 }
220
221 if (__ipv6_addr_needs_scope_id(addr_type)) {
222 if (addr_len >= sizeof(struct sockaddr_in6) &&
223 usin->sin6_scope_id) {
224 if (sk->sk_bound_dev_if &&
225 sk->sk_bound_dev_if != usin->sin6_scope_id) {
226 err = -EINVAL;
227 goto out;
228 }
229 sk->sk_bound_dev_if = usin->sin6_scope_id;
230 }
231
232 if (!sk->sk_bound_dev_if && (addr_type & IPV6_ADDR_MULTICAST))
233 sk->sk_bound_dev_if = np->mcast_oif;
234
235 /* Connect to link-local address requires an interface */
236 if (!sk->sk_bound_dev_if) {
237 err = -EINVAL;
238 goto out;
239 }
240 }
241
242 sk->sk_v6_daddr = *daddr;
243 np->flow_label = fl6_flowlabel;
244
245 inet->inet_dport = usin->sin6_port;
246
247 /*
248 * Check for a route to destination an obtain the
249 * destination cache for it.
250 */
251
252 err = ip6_datagram_dst_update(sk, true);
253 if (err)
254 goto out;
255
256 sk->sk_state = TCP_ESTABLISHED;
257 sk_set_txhash(sk);
258out:
259 return err;
260}
261EXPORT_SYMBOL_GPL(__ip6_datagram_connect);
262
263int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
264{
265 int res;
266
267 lock_sock(sk);
268 res = __ip6_datagram_connect(sk, uaddr, addr_len);
269 release_sock(sk);
270 return res;
271}
272EXPORT_SYMBOL_GPL(ip6_datagram_connect);
273
274int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *uaddr,
275 int addr_len)
276{
277 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, uaddr);
278 if (sin6->sin6_family != AF_INET6)
279 return -EAFNOSUPPORT;
280 return ip6_datagram_connect(sk, uaddr, addr_len);
281}
282EXPORT_SYMBOL_GPL(ip6_datagram_connect_v6_only);
283
284void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
285 __be16 port, u32 info, u8 *payload)
286{
287 struct ipv6_pinfo *np = inet6_sk(sk);
288 struct icmp6hdr *icmph = icmp6_hdr(skb);
289 struct sock_exterr_skb *serr;
290
291 if (!np->recverr)
292 return;
293
294 skb = skb_clone(skb, GFP_ATOMIC);
295 if (!skb)
296 return;
297
298 skb->protocol = htons(ETH_P_IPV6);
299
300 serr = SKB_EXT_ERR(skb);
301 serr->ee.ee_errno = err;
302 serr->ee.ee_origin = SO_EE_ORIGIN_ICMP6;
303 serr->ee.ee_type = icmph->icmp6_type;
304 serr->ee.ee_code = icmph->icmp6_code;
305 serr->ee.ee_pad = 0;
306 serr->ee.ee_info = info;
307 serr->ee.ee_data = 0;
308 serr->addr_offset = (u8 *)&(((struct ipv6hdr *)(icmph + 1))->daddr) -
309 skb_network_header(skb);
310 serr->port = port;
311
312 __skb_pull(skb, payload - skb->data);
313 skb_reset_transport_header(skb);
314
315 if (sock_queue_err_skb(sk, skb))
316 kfree_skb(skb);
317}
318
319void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info)
320{
321 const struct ipv6_pinfo *np = inet6_sk(sk);
322 struct sock_exterr_skb *serr;
323 struct ipv6hdr *iph;
324 struct sk_buff *skb;
325
326 if (!np->recverr)
327 return;
328
329 skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
330 if (!skb)
331 return;
332
333 skb->protocol = htons(ETH_P_IPV6);
334
335 skb_put(skb, sizeof(struct ipv6hdr));
336 skb_reset_network_header(skb);
337 iph = ipv6_hdr(skb);
338 iph->daddr = fl6->daddr;
339
340 serr = SKB_EXT_ERR(skb);
341 serr->ee.ee_errno = err;
342 serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
343 serr->ee.ee_type = 0;
344 serr->ee.ee_code = 0;
345 serr->ee.ee_pad = 0;
346 serr->ee.ee_info = info;
347 serr->ee.ee_data = 0;
348 serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
349 serr->port = fl6->fl6_dport;
350
351 __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
352 skb_reset_transport_header(skb);
353
354 if (sock_queue_err_skb(sk, skb))
355 kfree_skb(skb);
356}
357
358void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu)
359{
360 struct ipv6_pinfo *np = inet6_sk(sk);
361 struct ipv6hdr *iph;
362 struct sk_buff *skb;
363 struct ip6_mtuinfo *mtu_info;
364
365 if (!np->rxopt.bits.rxpmtu)
366 return;
367
368 skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
369 if (!skb)
370 return;
371
372 skb_put(skb, sizeof(struct ipv6hdr));
373 skb_reset_network_header(skb);
374 iph = ipv6_hdr(skb);
375 iph->daddr = fl6->daddr;
376
377 mtu_info = IP6CBMTU(skb);
378
379 mtu_info->ip6m_mtu = mtu;
380 mtu_info->ip6m_addr.sin6_family = AF_INET6;
381 mtu_info->ip6m_addr.sin6_port = 0;
382 mtu_info->ip6m_addr.sin6_flowinfo = 0;
383 mtu_info->ip6m_addr.sin6_scope_id = fl6->flowi6_oif;
384 mtu_info->ip6m_addr.sin6_addr = ipv6_hdr(skb)->daddr;
385
386 __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
387 skb_reset_transport_header(skb);
388
389 skb = xchg(&np->rxpmtu, skb);
390 kfree_skb(skb);
391}
392
393/* For some errors we have valid addr_offset even with zero payload and
394 * zero port. Also, addr_offset should be supported if port is set.
395 */
396static inline bool ipv6_datagram_support_addr(struct sock_exterr_skb *serr)
397{
398 return serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6 ||
399 serr->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
400 serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL || serr->port;
401}
402
403/* IPv6 supports cmsg on all origins aside from SO_EE_ORIGIN_LOCAL.
404 *
405 * At one point, excluding local errors was a quick test to identify icmp/icmp6
406 * errors. This is no longer true, but the test remained, so the v6 stack,
407 * unlike v4, also honors cmsg requests on all wifi and timestamp errors.
408 *
409 * Timestamp code paths do not initialize the fields expected by cmsg:
410 * the PKTINFO fields in skb->cb[]. Fill those in here.
411 */
412static bool ip6_datagram_support_cmsg(struct sk_buff *skb,
413 struct sock_exterr_skb *serr)
414{
415 if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
416 serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6)
417 return true;
418
419 if (serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL)
420 return false;
421
422 if (!skb->dev)
423 return false;
424
425 if (skb->protocol == htons(ETH_P_IPV6))
426 IP6CB(skb)->iif = skb->dev->ifindex;
427 else
428 PKTINFO_SKB_CB(skb)->ipi_ifindex = skb->dev->ifindex;
429
430 return true;
431}
432
433/*
434 * Handle MSG_ERRQUEUE
435 */
436int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
437{
438 struct ipv6_pinfo *np = inet6_sk(sk);
439 struct sock_exterr_skb *serr;
440 struct sk_buff *skb;
441 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name);
442 struct {
443 struct sock_extended_err ee;
444 struct sockaddr_in6 offender;
445 } errhdr;
446 int err;
447 int copied;
448
449 err = -EAGAIN;
450 skb = sock_dequeue_err_skb(sk);
451 if (!skb)
452 goto out;
453
454 copied = skb->len;
455 if (copied > len) {
456 msg->msg_flags |= MSG_TRUNC;
457 copied = len;
458 }
459 err = skb_copy_datagram_msg(skb, 0, msg, copied);
460 if (unlikely(err)) {
461 kfree_skb(skb);
462 return err;
463 }
464 sock_recv_timestamp(msg, sk, skb);
465
466 serr = SKB_EXT_ERR(skb);
467
468 if (sin && ipv6_datagram_support_addr(serr)) {
469 const unsigned char *nh = skb_network_header(skb);
470 sin->sin6_family = AF_INET6;
471 sin->sin6_flowinfo = 0;
472 sin->sin6_port = serr->port;
473 if (skb->protocol == htons(ETH_P_IPV6)) {
474 const struct ipv6hdr *ip6h = container_of((struct in6_addr *)(nh + serr->addr_offset),
475 struct ipv6hdr, daddr);
476 sin->sin6_addr = ip6h->daddr;
477 if (np->sndflow)
478 sin->sin6_flowinfo = ip6_flowinfo(ip6h);
479 sin->sin6_scope_id =
480 ipv6_iface_scope_id(&sin->sin6_addr,
481 IP6CB(skb)->iif);
482 } else {
483 ipv6_addr_set_v4mapped(*(__be32 *)(nh + serr->addr_offset),
484 &sin->sin6_addr);
485 sin->sin6_scope_id = 0;
486 }
487 *addr_len = sizeof(*sin);
488 }
489
490 memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
491 sin = &errhdr.offender;
492 memset(sin, 0, sizeof(*sin));
493
494 if (ip6_datagram_support_cmsg(skb, serr)) {
495 sin->sin6_family = AF_INET6;
496 if (np->rxopt.all)
497 ip6_datagram_recv_common_ctl(sk, msg, skb);
498 if (skb->protocol == htons(ETH_P_IPV6)) {
499 sin->sin6_addr = ipv6_hdr(skb)->saddr;
500 if (np->rxopt.all)
501 ip6_datagram_recv_specific_ctl(sk, msg, skb);
502 sin->sin6_scope_id =
503 ipv6_iface_scope_id(&sin->sin6_addr,
504 IP6CB(skb)->iif);
505 } else {
506 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
507 &sin->sin6_addr);
508 if (inet_sk(sk)->cmsg_flags)
509 ip_cmsg_recv(msg, skb);
510 }
511 }
512
513 put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr);
514
515 /* Now we could try to dump offended packet options */
516
517 msg->msg_flags |= MSG_ERRQUEUE;
518 err = copied;
519
520 consume_skb(skb);
521out:
522 return err;
523}
524EXPORT_SYMBOL_GPL(ipv6_recv_error);
525
526/*
527 * Handle IPV6_RECVPATHMTU
528 */
529int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len,
530 int *addr_len)
531{
532 struct ipv6_pinfo *np = inet6_sk(sk);
533 struct sk_buff *skb;
534 struct ip6_mtuinfo mtu_info;
535 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name);
536 int err;
537 int copied;
538
539 err = -EAGAIN;
540 skb = xchg(&np->rxpmtu, NULL);
541 if (!skb)
542 goto out;
543
544 copied = skb->len;
545 if (copied > len) {
546 msg->msg_flags |= MSG_TRUNC;
547 copied = len;
548 }
549 err = skb_copy_datagram_msg(skb, 0, msg, copied);
550 if (err)
551 goto out_free_skb;
552
553 sock_recv_timestamp(msg, sk, skb);
554
555 memcpy(&mtu_info, IP6CBMTU(skb), sizeof(mtu_info));
556
557 if (sin) {
558 sin->sin6_family = AF_INET6;
559 sin->sin6_flowinfo = 0;
560 sin->sin6_port = 0;
561 sin->sin6_scope_id = mtu_info.ip6m_addr.sin6_scope_id;
562 sin->sin6_addr = mtu_info.ip6m_addr.sin6_addr;
563 *addr_len = sizeof(*sin);
564 }
565
566 put_cmsg(msg, SOL_IPV6, IPV6_PATHMTU, sizeof(mtu_info), &mtu_info);
567
568 err = copied;
569
570out_free_skb:
571 kfree_skb(skb);
572out:
573 return err;
574}
575
576
577void ip6_datagram_recv_common_ctl(struct sock *sk, struct msghdr *msg,
578 struct sk_buff *skb)
579{
580 struct ipv6_pinfo *np = inet6_sk(sk);
581 bool is_ipv6 = skb->protocol == htons(ETH_P_IPV6);
582
583 if (np->rxopt.bits.rxinfo) {
584 struct in6_pktinfo src_info;
585
586 if (is_ipv6) {
587 src_info.ipi6_ifindex = IP6CB(skb)->iif;
588 src_info.ipi6_addr = ipv6_hdr(skb)->daddr;
589 } else {
590 src_info.ipi6_ifindex =
591 PKTINFO_SKB_CB(skb)->ipi_ifindex;
592 ipv6_addr_set_v4mapped(ip_hdr(skb)->daddr,
593 &src_info.ipi6_addr);
594 }
595
596 if (src_info.ipi6_ifindex >= 0)
597 put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO,
598 sizeof(src_info), &src_info);
599 }
600}
601
602void ip6_datagram_recv_specific_ctl(struct sock *sk, struct msghdr *msg,
603 struct sk_buff *skb)
604{
605 struct ipv6_pinfo *np = inet6_sk(sk);
606 struct inet6_skb_parm *opt = IP6CB(skb);
607 unsigned char *nh = skb_network_header(skb);
608
609 if (np->rxopt.bits.rxhlim) {
610 int hlim = ipv6_hdr(skb)->hop_limit;
611 put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
612 }
613
614 if (np->rxopt.bits.rxtclass) {
615 int tclass = ipv6_get_dsfield(ipv6_hdr(skb));
616 put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
617 }
618
619 if (np->rxopt.bits.rxflow) {
620 __be32 flowinfo = ip6_flowinfo((struct ipv6hdr *)nh);
621 if (flowinfo)
622 put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
623 }
624
625 /* HbH is allowed only once */
626 if (np->rxopt.bits.hopopts && (opt->flags & IP6SKB_HOPBYHOP)) {
627 u8 *ptr = nh + sizeof(struct ipv6hdr);
628 put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr);
629 }
630
631 if (opt->lastopt &&
632 (np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) {
633 /*
634 * Silly enough, but we need to reparse in order to
635 * report extension headers (except for HbH)
636 * in order.
637 *
638 * Also note that IPV6_RECVRTHDRDSTOPTS is NOT
639 * (and WILL NOT be) defined because
640 * IPV6_RECVDSTOPTS is more generic. --yoshfuji
641 */
642 unsigned int off = sizeof(struct ipv6hdr);
643 u8 nexthdr = ipv6_hdr(skb)->nexthdr;
644
645 while (off <= opt->lastopt) {
646 unsigned int len;
647 u8 *ptr = nh + off;
648
649 switch (nexthdr) {
650 case IPPROTO_DSTOPTS:
651 nexthdr = ptr[0];
652 len = (ptr[1] + 1) << 3;
653 if (np->rxopt.bits.dstopts)
654 put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, ptr);
655 break;
656 case IPPROTO_ROUTING:
657 nexthdr = ptr[0];
658 len = (ptr[1] + 1) << 3;
659 if (np->rxopt.bits.srcrt)
660 put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, ptr);
661 break;
662 case IPPROTO_AH:
663 nexthdr = ptr[0];
664 len = (ptr[1] + 2) << 2;
665 break;
666 default:
667 nexthdr = ptr[0];
668 len = (ptr[1] + 1) << 3;
669 break;
670 }
671
672 off += len;
673 }
674 }
675
676 /* socket options in old style */
677 if (np->rxopt.bits.rxoinfo) {
678 struct in6_pktinfo src_info;
679
680 src_info.ipi6_ifindex = opt->iif;
681 src_info.ipi6_addr = ipv6_hdr(skb)->daddr;
682 put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
683 }
684 if (np->rxopt.bits.rxohlim) {
685 int hlim = ipv6_hdr(skb)->hop_limit;
686 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
687 }
688 if (np->rxopt.bits.ohopopts && (opt->flags & IP6SKB_HOPBYHOP)) {
689 u8 *ptr = nh + sizeof(struct ipv6hdr);
690 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, (ptr[1]+1)<<3, ptr);
691 }
692 if (np->rxopt.bits.odstopts && opt->dst0) {
693 u8 *ptr = nh + opt->dst0;
694 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
695 }
696 if (np->rxopt.bits.osrcrt && opt->srcrt) {
697 struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt);
698 put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, (rthdr->hdrlen+1) << 3, rthdr);
699 }
700 if (np->rxopt.bits.odstopts && opt->dst1) {
701 u8 *ptr = nh + opt->dst1;
702 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
703 }
704 if (np->rxopt.bits.rxorigdstaddr) {
705 struct sockaddr_in6 sin6;
706 __be16 *ports = (__be16 *) skb_transport_header(skb);
707
708 if (skb_transport_offset(skb) + 4 <= (int)skb->len) {
709 /* All current transport protocols have the port numbers in the
710 * first four bytes of the transport header and this function is
711 * written with this assumption in mind.
712 */
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
732void 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}
738EXPORT_SYMBOL_GPL(ip6_datagram_recv_ctl);
739
740int ip6_datagram_send_ctl(struct net *net, struct sock *sk,
741 struct msghdr *msg, struct flowi6 *fl6,
742 struct ipcm6_cookie *ipc6, struct sockcm_cookie *sockc)
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, 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 (!(inet_sk(sk)->freebind || inet_sk(sk)->transparent) &&
807 !ipv6_chk_addr(net, &src_info->ipi6_addr,
808 strict ? dev : NULL, 0) &&
809 !ipv6_chk_acast_addr_src(net, dev,
810 &src_info->ipi6_addr))
811 err = -EINVAL;
812 else
813 fl6->saddr = src_info->ipi6_addr;
814 }
815
816 rcu_read_unlock();
817
818 if (err)
819 goto exit_f;
820
821 break;
822 }
823
824 case IPV6_FLOWINFO:
825 if (cmsg->cmsg_len < CMSG_LEN(4)) {
826 err = -EINVAL;
827 goto exit_f;
828 }
829
830 if (fl6->flowlabel&IPV6_FLOWINFO_MASK) {
831 if ((fl6->flowlabel^*(__be32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) {
832 err = -EINVAL;
833 goto exit_f;
834 }
835 }
836 fl6->flowlabel = IPV6_FLOWINFO_MASK & *(__be32 *)CMSG_DATA(cmsg);
837 break;
838
839 case IPV6_2292HOPOPTS:
840 case IPV6_HOPOPTS:
841 if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
842 err = -EINVAL;
843 goto exit_f;
844 }
845
846 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
847 len = ((hdr->hdrlen + 1) << 3);
848 if (cmsg->cmsg_len < CMSG_LEN(len)) {
849 err = -EINVAL;
850 goto exit_f;
851 }
852 if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
853 err = -EPERM;
854 goto exit_f;
855 }
856 opt->opt_nflen += len;
857 opt->hopopt = hdr;
858 break;
859
860 case IPV6_2292DSTOPTS:
861 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
862 err = -EINVAL;
863 goto exit_f;
864 }
865
866 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
867 len = ((hdr->hdrlen + 1) << 3);
868 if (cmsg->cmsg_len < CMSG_LEN(len)) {
869 err = -EINVAL;
870 goto exit_f;
871 }
872 if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
873 err = -EPERM;
874 goto exit_f;
875 }
876 if (opt->dst1opt) {
877 err = -EINVAL;
878 goto exit_f;
879 }
880 opt->opt_flen += len;
881 opt->dst1opt = hdr;
882 break;
883
884 case IPV6_DSTOPTS:
885 case IPV6_RTHDRDSTOPTS:
886 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
887 err = -EINVAL;
888 goto exit_f;
889 }
890
891 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
892 len = ((hdr->hdrlen + 1) << 3);
893 if (cmsg->cmsg_len < CMSG_LEN(len)) {
894 err = -EINVAL;
895 goto exit_f;
896 }
897 if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
898 err = -EPERM;
899 goto exit_f;
900 }
901 if (cmsg->cmsg_type == IPV6_DSTOPTS) {
902 opt->opt_flen += len;
903 opt->dst1opt = hdr;
904 } else {
905 opt->opt_nflen += len;
906 opt->dst0opt = hdr;
907 }
908 break;
909
910 case IPV6_2292RTHDR:
911 case IPV6_RTHDR:
912 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) {
913 err = -EINVAL;
914 goto exit_f;
915 }
916
917 rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg);
918
919 switch (rthdr->type) {
920#if IS_ENABLED(CONFIG_IPV6_MIP6)
921 case IPV6_SRCRT_TYPE_2:
922 if (rthdr->hdrlen != 2 ||
923 rthdr->segments_left != 1) {
924 err = -EINVAL;
925 goto exit_f;
926 }
927 break;
928#endif
929 default:
930 err = -EINVAL;
931 goto exit_f;
932 }
933
934 len = ((rthdr->hdrlen + 1) << 3);
935
936 if (cmsg->cmsg_len < CMSG_LEN(len)) {
937 err = -EINVAL;
938 goto exit_f;
939 }
940
941 /* segments left must also match */
942 if ((rthdr->hdrlen >> 1) != rthdr->segments_left) {
943 err = -EINVAL;
944 goto exit_f;
945 }
946
947 opt->opt_nflen += len;
948 opt->srcrt = rthdr;
949
950 if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) {
951 int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3);
952
953 opt->opt_nflen += dsthdrlen;
954 opt->dst0opt = opt->dst1opt;
955 opt->dst1opt = NULL;
956 opt->opt_flen -= dsthdrlen;
957 }
958
959 break;
960
961 case IPV6_2292HOPLIMIT:
962 case IPV6_HOPLIMIT:
963 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
964 err = -EINVAL;
965 goto exit_f;
966 }
967
968 ipc6->hlimit = *(int *)CMSG_DATA(cmsg);
969 if (ipc6->hlimit < -1 || ipc6->hlimit > 0xff) {
970 err = -EINVAL;
971 goto exit_f;
972 }
973
974 break;
975
976 case IPV6_TCLASS:
977 {
978 int tc;
979
980 err = -EINVAL;
981 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
982 goto exit_f;
983
984 tc = *(int *)CMSG_DATA(cmsg);
985 if (tc < -1 || tc > 0xff)
986 goto exit_f;
987
988 err = 0;
989 ipc6->tclass = tc;
990
991 break;
992 }
993
994 case IPV6_DONTFRAG:
995 {
996 int df;
997
998 err = -EINVAL;
999 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
1000 goto exit_f;
1001
1002 df = *(int *)CMSG_DATA(cmsg);
1003 if (df < 0 || df > 1)
1004 goto exit_f;
1005
1006 err = 0;
1007 ipc6->dontfrag = df;
1008
1009 break;
1010 }
1011 default:
1012 net_dbg_ratelimited("invalid cmsg type: %d\n",
1013 cmsg->cmsg_type);
1014 err = -EINVAL;
1015 goto exit_f;
1016 }
1017 }
1018
1019exit_f:
1020 return err;
1021}
1022EXPORT_SYMBOL_GPL(ip6_datagram_send_ctl);
1023
1024void ip6_dgram_sock_seq_show(struct seq_file *seq, struct sock *sp,
1025 __u16 srcp, __u16 destp, int bucket)
1026{
1027 const struct in6_addr *dest, *src;
1028
1029 dest = &sp->sk_v6_daddr;
1030 src = &sp->sk_v6_rcv_saddr;
1031 seq_printf(seq,
1032 "%5d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1033 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %d\n",
1034 bucket,
1035 src->s6_addr32[0], src->s6_addr32[1],
1036 src->s6_addr32[2], src->s6_addr32[3], srcp,
1037 dest->s6_addr32[0], dest->s6_addr32[1],
1038 dest->s6_addr32[2], dest->s6_addr32[3], destp,
1039 sp->sk_state,
1040 sk_wmem_alloc_get(sp),
1041 sk_rmem_alloc_get(sp),
1042 0, 0L, 0,
1043 from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)),
1044 0,
1045 sock_i_ino(sp),
1046 atomic_read(&sp->sk_refcnt), sp,
1047 atomic_read(&sp->sk_drops));
1048}