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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// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * common UDP/RAW code
4 * Linux INET6 implementation
5 *
6 * Authors:
7 * Pedro Roque <roque@di.fc.ul.pt>
8 */
9
10#include <linux/capability.h>
11#include <linux/errno.h>
12#include <linux/types.h>
13#include <linux/kernel.h>
14#include <linux/interrupt.h>
15#include <linux/socket.h>
16#include <linux/sockios.h>
17#include <linux/in6.h>
18#include <linux/ipv6.h>
19#include <linux/route.h>
20#include <linux/slab.h>
21#include <linux/export.h>
22#include <linux/icmp.h>
23
24#include <net/ipv6.h>
25#include <net/ndisc.h>
26#include <net/addrconf.h>
27#include <net/transp_v6.h>
28#include <net/ip6_route.h>
29#include <net/tcp_states.h>
30#include <net/dsfield.h>
31#include <net/sock_reuseport.h>
32
33#include <linux/errqueue.h>
34#include <linux/uaccess.h>
35
36static bool ipv6_mapped_addr_any(const struct in6_addr *a)
37{
38 return ipv6_addr_v4mapped(a) && (a->s6_addr32[3] == 0);
39}
40
41static void ip6_datagram_flow_key_init(struct flowi6 *fl6, struct sock *sk)
42{
43 struct inet_sock *inet = inet_sk(sk);
44 struct ipv6_pinfo *np = inet6_sk(sk);
45 int oif = sk->sk_bound_dev_if;
46
47 memset(fl6, 0, sizeof(*fl6));
48 fl6->flowi6_proto = sk->sk_protocol;
49 fl6->daddr = sk->sk_v6_daddr;
50 fl6->saddr = np->saddr;
51 fl6->flowi6_mark = sk->sk_mark;
52 fl6->fl6_dport = inet->inet_dport;
53 fl6->fl6_sport = inet->inet_sport;
54 fl6->flowlabel = ip6_make_flowinfo(np->tclass, np->flow_label);
55 fl6->flowi6_uid = sk->sk_uid;
56
57 if (!oif)
58 oif = np->sticky_pktinfo.ipi6_ifindex;
59
60 if (!oif) {
61 if (ipv6_addr_is_multicast(&fl6->daddr))
62 oif = np->mcast_oif;
63 else
64 oif = np->ucast_oif;
65 }
66
67 fl6->flowi6_oif = oif;
68 security_sk_classify_flow(sk, flowi6_to_flowi_common(fl6));
69}
70
71int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr)
72{
73 struct ip6_flowlabel *flowlabel = NULL;
74 struct in6_addr *final_p, final;
75 struct ipv6_txoptions *opt;
76 struct dst_entry *dst;
77 struct inet_sock *inet = inet_sk(sk);
78 struct ipv6_pinfo *np = inet6_sk(sk);
79 struct flowi6 fl6;
80 int err = 0;
81
82 if (np->sndflow && (np->flow_label & IPV6_FLOWLABEL_MASK)) {
83 flowlabel = fl6_sock_lookup(sk, np->flow_label);
84 if (IS_ERR(flowlabel))
85 return -EINVAL;
86 }
87 ip6_datagram_flow_key_init(&fl6, sk);
88
89 rcu_read_lock();
90 opt = flowlabel ? flowlabel->opt : rcu_dereference(np->opt);
91 final_p = fl6_update_dst(&fl6, opt, &final);
92 rcu_read_unlock();
93
94 dst = ip6_dst_lookup_flow(sock_net(sk), sk, &fl6, final_p);
95 if (IS_ERR(dst)) {
96 err = PTR_ERR(dst);
97 goto out;
98 }
99
100 if (fix_sk_saddr) {
101 if (ipv6_addr_any(&np->saddr))
102 np->saddr = fl6.saddr;
103
104 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr)) {
105 sk->sk_v6_rcv_saddr = fl6.saddr;
106 inet->inet_rcv_saddr = LOOPBACK4_IPV6;
107 if (sk->sk_prot->rehash)
108 sk->sk_prot->rehash(sk);
109 }
110 }
111
112 ip6_sk_dst_store_flow(sk, dst, &fl6);
113
114out:
115 fl6_sock_release(flowlabel);
116 return err;
117}
118
119void ip6_datagram_release_cb(struct sock *sk)
120{
121 struct dst_entry *dst;
122
123 if (ipv6_addr_v4mapped(&sk->sk_v6_daddr))
124 return;
125
126 rcu_read_lock();
127 dst = __sk_dst_get(sk);
128 if (!dst || !dst->obsolete ||
129 dst->ops->check(dst, inet6_sk(sk)->dst_cookie)) {
130 rcu_read_unlock();
131 return;
132 }
133 rcu_read_unlock();
134
135 ip6_datagram_dst_update(sk, false);
136}
137EXPORT_SYMBOL_GPL(ip6_datagram_release_cb);
138
139int __ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr,
140 int addr_len)
141{
142 struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr;
143 struct inet_sock *inet = inet_sk(sk);
144 struct ipv6_pinfo *np = inet6_sk(sk);
145 struct in6_addr *daddr, old_daddr;
146 __be32 fl6_flowlabel = 0;
147 __be32 old_fl6_flowlabel;
148 __be16 old_dport;
149 int addr_type;
150 int err;
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 if (ipv6_addr_any(&usin->sin6_addr)) {
169 /*
170 * connect to self
171 */
172 if (ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr))
173 ipv6_addr_set_v4mapped(htonl(INADDR_LOOPBACK),
174 &usin->sin6_addr);
175 else
176 usin->sin6_addr = in6addr_loopback;
177 }
178
179 addr_type = ipv6_addr_type(&usin->sin6_addr);
180
181 daddr = &usin->sin6_addr;
182
183 if (addr_type & IPV6_ADDR_MAPPED) {
184 struct sockaddr_in sin;
185
186 if (ipv6_only_sock(sk)) {
187 err = -ENETUNREACH;
188 goto out;
189 }
190 sin.sin_family = AF_INET;
191 sin.sin_addr.s_addr = daddr->s6_addr32[3];
192 sin.sin_port = usin->sin6_port;
193
194 err = __ip4_datagram_connect(sk,
195 (struct sockaddr *) &sin,
196 sizeof(sin));
197
198ipv4_connected:
199 if (err)
200 goto out;
201
202 ipv6_addr_set_v4mapped(inet->inet_daddr, &sk->sk_v6_daddr);
203
204 if (ipv6_addr_any(&np->saddr) ||
205 ipv6_mapped_addr_any(&np->saddr))
206 ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr);
207
208 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr) ||
209 ipv6_mapped_addr_any(&sk->sk_v6_rcv_saddr)) {
210 ipv6_addr_set_v4mapped(inet->inet_rcv_saddr,
211 &sk->sk_v6_rcv_saddr);
212 if (sk->sk_prot->rehash)
213 sk->sk_prot->rehash(sk);
214 }
215
216 goto out;
217 }
218
219 if (__ipv6_addr_needs_scope_id(addr_type)) {
220 if (addr_len >= sizeof(struct sockaddr_in6) &&
221 usin->sin6_scope_id) {
222 if (!sk_dev_equal_l3scope(sk, usin->sin6_scope_id)) {
223 err = -EINVAL;
224 goto out;
225 }
226 WRITE_ONCE(sk->sk_bound_dev_if, usin->sin6_scope_id);
227 }
228
229 if (!sk->sk_bound_dev_if && (addr_type & IPV6_ADDR_MULTICAST))
230 WRITE_ONCE(sk->sk_bound_dev_if, np->mcast_oif);
231
232 /* Connect to link-local address requires an interface */
233 if (!sk->sk_bound_dev_if) {
234 err = -EINVAL;
235 goto out;
236 }
237 }
238
239 /* save the current peer information before updating it */
240 old_daddr = sk->sk_v6_daddr;
241 old_fl6_flowlabel = np->flow_label;
242 old_dport = inet->inet_dport;
243
244 sk->sk_v6_daddr = *daddr;
245 np->flow_label = fl6_flowlabel;
246 inet->inet_dport = usin->sin6_port;
247
248 /*
249 * Check for a route to destination an obtain the
250 * destination cache for it.
251 */
252
253 err = ip6_datagram_dst_update(sk, true);
254 if (err) {
255 /* Restore the socket peer info, to keep it consistent with
256 * the old socket state
257 */
258 sk->sk_v6_daddr = old_daddr;
259 np->flow_label = old_fl6_flowlabel;
260 inet->inet_dport = old_dport;
261 goto out;
262 }
263
264 reuseport_has_conns_set(sk);
265 sk->sk_state = TCP_ESTABLISHED;
266 sk_set_txhash(sk);
267out:
268 return err;
269}
270EXPORT_SYMBOL_GPL(__ip6_datagram_connect);
271
272int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
273{
274 int res;
275
276 lock_sock(sk);
277 res = __ip6_datagram_connect(sk, uaddr, addr_len);
278 release_sock(sk);
279 return res;
280}
281EXPORT_SYMBOL_GPL(ip6_datagram_connect);
282
283int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *uaddr,
284 int addr_len)
285{
286 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, uaddr);
287 if (sin6->sin6_family != AF_INET6)
288 return -EAFNOSUPPORT;
289 return ip6_datagram_connect(sk, uaddr, addr_len);
290}
291EXPORT_SYMBOL_GPL(ip6_datagram_connect_v6_only);
292
293static void ipv6_icmp_error_rfc4884(const struct sk_buff *skb,
294 struct sock_ee_data_rfc4884 *out)
295{
296 switch (icmp6_hdr(skb)->icmp6_type) {
297 case ICMPV6_TIME_EXCEED:
298 case ICMPV6_DEST_UNREACH:
299 ip_icmp_error_rfc4884(skb, out, sizeof(struct icmp6hdr),
300 icmp6_hdr(skb)->icmp6_datagram_len * 8);
301 }
302}
303
304void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
305 __be16 port, u32 info, u8 *payload)
306{
307 struct ipv6_pinfo *np = inet6_sk(sk);
308 struct icmp6hdr *icmph = icmp6_hdr(skb);
309 struct sock_exterr_skb *serr;
310
311 if (!np->recverr)
312 return;
313
314 skb = skb_clone(skb, GFP_ATOMIC);
315 if (!skb)
316 return;
317
318 skb->protocol = htons(ETH_P_IPV6);
319
320 serr = SKB_EXT_ERR(skb);
321 serr->ee.ee_errno = err;
322 serr->ee.ee_origin = SO_EE_ORIGIN_ICMP6;
323 serr->ee.ee_type = icmph->icmp6_type;
324 serr->ee.ee_code = icmph->icmp6_code;
325 serr->ee.ee_pad = 0;
326 serr->ee.ee_info = info;
327 serr->ee.ee_data = 0;
328 serr->addr_offset = (u8 *)&(((struct ipv6hdr *)(icmph + 1))->daddr) -
329 skb_network_header(skb);
330 serr->port = port;
331
332 __skb_pull(skb, payload - skb->data);
333
334 if (inet6_sk(sk)->recverr_rfc4884)
335 ipv6_icmp_error_rfc4884(skb, &serr->ee.ee_rfc4884);
336
337 skb_reset_transport_header(skb);
338
339 if (sock_queue_err_skb(sk, skb))
340 kfree_skb(skb);
341}
342EXPORT_SYMBOL_GPL(ipv6_icmp_error);
343
344void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info)
345{
346 const struct ipv6_pinfo *np = inet6_sk(sk);
347 struct sock_exterr_skb *serr;
348 struct ipv6hdr *iph;
349 struct sk_buff *skb;
350
351 if (!np->recverr)
352 return;
353
354 skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
355 if (!skb)
356 return;
357
358 skb->protocol = htons(ETH_P_IPV6);
359
360 skb_put(skb, sizeof(struct ipv6hdr));
361 skb_reset_network_header(skb);
362 iph = ipv6_hdr(skb);
363 iph->daddr = fl6->daddr;
364 ip6_flow_hdr(iph, 0, 0);
365
366 serr = SKB_EXT_ERR(skb);
367 serr->ee.ee_errno = err;
368 serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
369 serr->ee.ee_type = 0;
370 serr->ee.ee_code = 0;
371 serr->ee.ee_pad = 0;
372 serr->ee.ee_info = info;
373 serr->ee.ee_data = 0;
374 serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
375 serr->port = fl6->fl6_dport;
376
377 __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
378 skb_reset_transport_header(skb);
379
380 if (sock_queue_err_skb(sk, skb))
381 kfree_skb(skb);
382}
383
384void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu)
385{
386 struct ipv6_pinfo *np = inet6_sk(sk);
387 struct ipv6hdr *iph;
388 struct sk_buff *skb;
389 struct ip6_mtuinfo *mtu_info;
390
391 if (!np->rxopt.bits.rxpmtu)
392 return;
393
394 skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
395 if (!skb)
396 return;
397
398 skb_put(skb, sizeof(struct ipv6hdr));
399 skb_reset_network_header(skb);
400 iph = ipv6_hdr(skb);
401 iph->daddr = fl6->daddr;
402
403 mtu_info = IP6CBMTU(skb);
404
405 mtu_info->ip6m_mtu = mtu;
406 mtu_info->ip6m_addr.sin6_family = AF_INET6;
407 mtu_info->ip6m_addr.sin6_port = 0;
408 mtu_info->ip6m_addr.sin6_flowinfo = 0;
409 mtu_info->ip6m_addr.sin6_scope_id = fl6->flowi6_oif;
410 mtu_info->ip6m_addr.sin6_addr = ipv6_hdr(skb)->daddr;
411
412 __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
413 skb_reset_transport_header(skb);
414
415 skb = xchg(&np->rxpmtu, skb);
416 kfree_skb(skb);
417}
418
419/* For some errors we have valid addr_offset even with zero payload and
420 * zero port. Also, addr_offset should be supported if port is set.
421 */
422static inline bool ipv6_datagram_support_addr(struct sock_exterr_skb *serr)
423{
424 return serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6 ||
425 serr->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
426 serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL || serr->port;
427}
428
429/* IPv6 supports cmsg on all origins aside from SO_EE_ORIGIN_LOCAL.
430 *
431 * At one point, excluding local errors was a quick test to identify icmp/icmp6
432 * errors. This is no longer true, but the test remained, so the v6 stack,
433 * unlike v4, also honors cmsg requests on all wifi and timestamp errors.
434 */
435static bool ip6_datagram_support_cmsg(struct sk_buff *skb,
436 struct sock_exterr_skb *serr)
437{
438 if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
439 serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6)
440 return true;
441
442 if (serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL)
443 return false;
444
445 if (!IP6CB(skb)->iif)
446 return false;
447
448 return true;
449}
450
451/*
452 * Handle MSG_ERRQUEUE
453 */
454int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
455{
456 struct ipv6_pinfo *np = inet6_sk(sk);
457 struct sock_exterr_skb *serr;
458 struct sk_buff *skb;
459 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name);
460 struct {
461 struct sock_extended_err ee;
462 struct sockaddr_in6 offender;
463 } errhdr;
464 int err;
465 int copied;
466
467 err = -EAGAIN;
468 skb = sock_dequeue_err_skb(sk);
469 if (!skb)
470 goto out;
471
472 copied = skb->len;
473 if (copied > len) {
474 msg->msg_flags |= MSG_TRUNC;
475 copied = len;
476 }
477 err = skb_copy_datagram_msg(skb, 0, msg, copied);
478 if (unlikely(err)) {
479 kfree_skb(skb);
480 return err;
481 }
482 sock_recv_timestamp(msg, sk, skb);
483
484 serr = SKB_EXT_ERR(skb);
485
486 if (sin && ipv6_datagram_support_addr(serr)) {
487 const unsigned char *nh = skb_network_header(skb);
488 sin->sin6_family = AF_INET6;
489 sin->sin6_flowinfo = 0;
490 sin->sin6_port = serr->port;
491 if (skb->protocol == htons(ETH_P_IPV6)) {
492 const struct ipv6hdr *ip6h = container_of((struct in6_addr *)(nh + serr->addr_offset),
493 struct ipv6hdr, daddr);
494 sin->sin6_addr = ip6h->daddr;
495 if (np->sndflow)
496 sin->sin6_flowinfo = ip6_flowinfo(ip6h);
497 sin->sin6_scope_id =
498 ipv6_iface_scope_id(&sin->sin6_addr,
499 IP6CB(skb)->iif);
500 } else {
501 ipv6_addr_set_v4mapped(*(__be32 *)(nh + serr->addr_offset),
502 &sin->sin6_addr);
503 sin->sin6_scope_id = 0;
504 }
505 *addr_len = sizeof(*sin);
506 }
507
508 memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
509 sin = &errhdr.offender;
510 memset(sin, 0, sizeof(*sin));
511
512 if (ip6_datagram_support_cmsg(skb, serr)) {
513 sin->sin6_family = AF_INET6;
514 if (np->rxopt.all)
515 ip6_datagram_recv_common_ctl(sk, msg, skb);
516 if (skb->protocol == htons(ETH_P_IPV6)) {
517 sin->sin6_addr = ipv6_hdr(skb)->saddr;
518 if (np->rxopt.all)
519 ip6_datagram_recv_specific_ctl(sk, msg, skb);
520 sin->sin6_scope_id =
521 ipv6_iface_scope_id(&sin->sin6_addr,
522 IP6CB(skb)->iif);
523 } else {
524 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
525 &sin->sin6_addr);
526 if (inet_sk(sk)->cmsg_flags)
527 ip_cmsg_recv(msg, skb);
528 }
529 }
530
531 put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr);
532
533 /* Now we could try to dump offended packet options */
534
535 msg->msg_flags |= MSG_ERRQUEUE;
536 err = copied;
537
538 consume_skb(skb);
539out:
540 return err;
541}
542EXPORT_SYMBOL_GPL(ipv6_recv_error);
543
544/*
545 * Handle IPV6_RECVPATHMTU
546 */
547int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len,
548 int *addr_len)
549{
550 struct ipv6_pinfo *np = inet6_sk(sk);
551 struct sk_buff *skb;
552 struct ip6_mtuinfo mtu_info;
553 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name);
554 int err;
555 int copied;
556
557 err = -EAGAIN;
558 skb = xchg(&np->rxpmtu, NULL);
559 if (!skb)
560 goto out;
561
562 copied = skb->len;
563 if (copied > len) {
564 msg->msg_flags |= MSG_TRUNC;
565 copied = len;
566 }
567 err = skb_copy_datagram_msg(skb, 0, msg, copied);
568 if (err)
569 goto out_free_skb;
570
571 sock_recv_timestamp(msg, sk, skb);
572
573 memcpy(&mtu_info, IP6CBMTU(skb), sizeof(mtu_info));
574
575 if (sin) {
576 sin->sin6_family = AF_INET6;
577 sin->sin6_flowinfo = 0;
578 sin->sin6_port = 0;
579 sin->sin6_scope_id = mtu_info.ip6m_addr.sin6_scope_id;
580 sin->sin6_addr = mtu_info.ip6m_addr.sin6_addr;
581 *addr_len = sizeof(*sin);
582 }
583
584 put_cmsg(msg, SOL_IPV6, IPV6_PATHMTU, sizeof(mtu_info), &mtu_info);
585
586 err = copied;
587
588out_free_skb:
589 kfree_skb(skb);
590out:
591 return err;
592}
593
594
595void ip6_datagram_recv_common_ctl(struct sock *sk, struct msghdr *msg,
596 struct sk_buff *skb)
597{
598 struct ipv6_pinfo *np = inet6_sk(sk);
599 bool is_ipv6 = skb->protocol == htons(ETH_P_IPV6);
600
601 if (np->rxopt.bits.rxinfo) {
602 struct in6_pktinfo src_info;
603
604 if (is_ipv6) {
605 src_info.ipi6_ifindex = IP6CB(skb)->iif;
606 src_info.ipi6_addr = ipv6_hdr(skb)->daddr;
607 } else {
608 src_info.ipi6_ifindex =
609 PKTINFO_SKB_CB(skb)->ipi_ifindex;
610 ipv6_addr_set_v4mapped(ip_hdr(skb)->daddr,
611 &src_info.ipi6_addr);
612 }
613
614 if (src_info.ipi6_ifindex >= 0)
615 put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO,
616 sizeof(src_info), &src_info);
617 }
618}
619
620void ip6_datagram_recv_specific_ctl(struct sock *sk, struct msghdr *msg,
621 struct sk_buff *skb)
622{
623 struct ipv6_pinfo *np = inet6_sk(sk);
624 struct inet6_skb_parm *opt = IP6CB(skb);
625 unsigned char *nh = skb_network_header(skb);
626
627 if (np->rxopt.bits.rxhlim) {
628 int hlim = ipv6_hdr(skb)->hop_limit;
629 put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
630 }
631
632 if (np->rxopt.bits.rxtclass) {
633 int tclass = ipv6_get_dsfield(ipv6_hdr(skb));
634 put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
635 }
636
637 if (np->rxopt.bits.rxflow) {
638 __be32 flowinfo = ip6_flowinfo((struct ipv6hdr *)nh);
639 if (flowinfo)
640 put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
641 }
642
643 /* HbH is allowed only once */
644 if (np->rxopt.bits.hopopts && (opt->flags & IP6SKB_HOPBYHOP)) {
645 u8 *ptr = nh + sizeof(struct ipv6hdr);
646 put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr);
647 }
648
649 if (opt->lastopt &&
650 (np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) {
651 /*
652 * Silly enough, but we need to reparse in order to
653 * report extension headers (except for HbH)
654 * in order.
655 *
656 * Also note that IPV6_RECVRTHDRDSTOPTS is NOT
657 * (and WILL NOT be) defined because
658 * IPV6_RECVDSTOPTS is more generic. --yoshfuji
659 */
660 unsigned int off = sizeof(struct ipv6hdr);
661 u8 nexthdr = ipv6_hdr(skb)->nexthdr;
662
663 while (off <= opt->lastopt) {
664 unsigned int len;
665 u8 *ptr = nh + off;
666
667 switch (nexthdr) {
668 case IPPROTO_DSTOPTS:
669 nexthdr = ptr[0];
670 len = (ptr[1] + 1) << 3;
671 if (np->rxopt.bits.dstopts)
672 put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, ptr);
673 break;
674 case IPPROTO_ROUTING:
675 nexthdr = ptr[0];
676 len = (ptr[1] + 1) << 3;
677 if (np->rxopt.bits.srcrt)
678 put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, ptr);
679 break;
680 case IPPROTO_AH:
681 nexthdr = ptr[0];
682 len = (ptr[1] + 2) << 2;
683 break;
684 default:
685 nexthdr = ptr[0];
686 len = (ptr[1] + 1) << 3;
687 break;
688 }
689
690 off += len;
691 }
692 }
693
694 /* socket options in old style */
695 if (np->rxopt.bits.rxoinfo) {
696 struct in6_pktinfo src_info;
697
698 src_info.ipi6_ifindex = opt->iif;
699 src_info.ipi6_addr = ipv6_hdr(skb)->daddr;
700 put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
701 }
702 if (np->rxopt.bits.rxohlim) {
703 int hlim = ipv6_hdr(skb)->hop_limit;
704 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
705 }
706 if (np->rxopt.bits.ohopopts && (opt->flags & IP6SKB_HOPBYHOP)) {
707 u8 *ptr = nh + sizeof(struct ipv6hdr);
708 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, (ptr[1]+1)<<3, ptr);
709 }
710 if (np->rxopt.bits.odstopts && opt->dst0) {
711 u8 *ptr = nh + opt->dst0;
712 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
713 }
714 if (np->rxopt.bits.osrcrt && opt->srcrt) {
715 struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt);
716 put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, (rthdr->hdrlen+1) << 3, rthdr);
717 }
718 if (np->rxopt.bits.odstopts && opt->dst1) {
719 u8 *ptr = nh + opt->dst1;
720 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
721 }
722 if (np->rxopt.bits.rxorigdstaddr) {
723 struct sockaddr_in6 sin6;
724 __be16 _ports[2], *ports;
725
726 ports = skb_header_pointer(skb, skb_transport_offset(skb),
727 sizeof(_ports), &_ports);
728 if (ports) {
729 /* All current transport protocols have the port numbers in the
730 * first four bytes of the transport header and this function is
731 * written with this assumption in mind.
732 */
733 sin6.sin6_family = AF_INET6;
734 sin6.sin6_addr = ipv6_hdr(skb)->daddr;
735 sin6.sin6_port = ports[1];
736 sin6.sin6_flowinfo = 0;
737 sin6.sin6_scope_id =
738 ipv6_iface_scope_id(&ipv6_hdr(skb)->daddr,
739 opt->iif);
740
741 put_cmsg(msg, SOL_IPV6, IPV6_ORIGDSTADDR, sizeof(sin6), &sin6);
742 }
743 }
744 if (np->rxopt.bits.recvfragsize && opt->frag_max_size) {
745 int val = opt->frag_max_size;
746
747 put_cmsg(msg, SOL_IPV6, IPV6_RECVFRAGSIZE, sizeof(val), &val);
748 }
749}
750
751void ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg,
752 struct sk_buff *skb)
753{
754 ip6_datagram_recv_common_ctl(sk, msg, skb);
755 ip6_datagram_recv_specific_ctl(sk, msg, skb);
756}
757EXPORT_SYMBOL_GPL(ip6_datagram_recv_ctl);
758
759int ip6_datagram_send_ctl(struct net *net, struct sock *sk,
760 struct msghdr *msg, struct flowi6 *fl6,
761 struct ipcm6_cookie *ipc6)
762{
763 struct in6_pktinfo *src_info;
764 struct cmsghdr *cmsg;
765 struct ipv6_rt_hdr *rthdr;
766 struct ipv6_opt_hdr *hdr;
767 struct ipv6_txoptions *opt = ipc6->opt;
768 int len;
769 int err = 0;
770
771 for_each_cmsghdr(cmsg, msg) {
772 int addr_type;
773
774 if (!CMSG_OK(msg, cmsg)) {
775 err = -EINVAL;
776 goto exit_f;
777 }
778
779 if (cmsg->cmsg_level == SOL_SOCKET) {
780 err = __sock_cmsg_send(sk, cmsg, &ipc6->sockc);
781 if (err)
782 return err;
783 continue;
784 }
785
786 if (cmsg->cmsg_level != SOL_IPV6)
787 continue;
788
789 switch (cmsg->cmsg_type) {
790 case IPV6_PKTINFO:
791 case IPV6_2292PKTINFO:
792 {
793 struct net_device *dev = NULL;
794 int src_idx;
795
796 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) {
797 err = -EINVAL;
798 goto exit_f;
799 }
800
801 src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
802 src_idx = src_info->ipi6_ifindex;
803
804 if (src_idx) {
805 if (fl6->flowi6_oif &&
806 src_idx != fl6->flowi6_oif &&
807 (READ_ONCE(sk->sk_bound_dev_if) != fl6->flowi6_oif ||
808 !sk_dev_equal_l3scope(sk, src_idx)))
809 return -EINVAL;
810 fl6->flowi6_oif = src_idx;
811 }
812
813 addr_type = __ipv6_addr_type(&src_info->ipi6_addr);
814
815 rcu_read_lock();
816 if (fl6->flowi6_oif) {
817 dev = dev_get_by_index_rcu(net, fl6->flowi6_oif);
818 if (!dev) {
819 rcu_read_unlock();
820 return -ENODEV;
821 }
822 } else if (addr_type & IPV6_ADDR_LINKLOCAL) {
823 rcu_read_unlock();
824 return -EINVAL;
825 }
826
827 if (addr_type != IPV6_ADDR_ANY) {
828 int strict = __ipv6_addr_src_scope(addr_type) <= IPV6_ADDR_SCOPE_LINKLOCAL;
829 if (!ipv6_can_nonlocal_bind(net, inet_sk(sk)) &&
830 !ipv6_chk_addr_and_flags(net, &src_info->ipi6_addr,
831 dev, !strict, 0,
832 IFA_F_TENTATIVE) &&
833 !ipv6_chk_acast_addr_src(net, dev,
834 &src_info->ipi6_addr))
835 err = -EINVAL;
836 else
837 fl6->saddr = src_info->ipi6_addr;
838 }
839
840 rcu_read_unlock();
841
842 if (err)
843 goto exit_f;
844
845 break;
846 }
847
848 case IPV6_FLOWINFO:
849 if (cmsg->cmsg_len < CMSG_LEN(4)) {
850 err = -EINVAL;
851 goto exit_f;
852 }
853
854 if (fl6->flowlabel&IPV6_FLOWINFO_MASK) {
855 if ((fl6->flowlabel^*(__be32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) {
856 err = -EINVAL;
857 goto exit_f;
858 }
859 }
860 fl6->flowlabel = IPV6_FLOWINFO_MASK & *(__be32 *)CMSG_DATA(cmsg);
861 break;
862
863 case IPV6_2292HOPOPTS:
864 case IPV6_HOPOPTS:
865 if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
866 err = -EINVAL;
867 goto exit_f;
868 }
869
870 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
871 len = ((hdr->hdrlen + 1) << 3);
872 if (cmsg->cmsg_len < CMSG_LEN(len)) {
873 err = -EINVAL;
874 goto exit_f;
875 }
876 if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
877 err = -EPERM;
878 goto exit_f;
879 }
880 opt->opt_nflen += len;
881 opt->hopopt = hdr;
882 break;
883
884 case IPV6_2292DSTOPTS:
885 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
886 err = -EINVAL;
887 goto exit_f;
888 }
889
890 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
891 len = ((hdr->hdrlen + 1) << 3);
892 if (cmsg->cmsg_len < CMSG_LEN(len)) {
893 err = -EINVAL;
894 goto exit_f;
895 }
896 if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
897 err = -EPERM;
898 goto exit_f;
899 }
900 if (opt->dst1opt) {
901 err = -EINVAL;
902 goto exit_f;
903 }
904 opt->opt_flen += len;
905 opt->dst1opt = hdr;
906 break;
907
908 case IPV6_DSTOPTS:
909 case IPV6_RTHDRDSTOPTS:
910 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
911 err = -EINVAL;
912 goto exit_f;
913 }
914
915 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
916 len = ((hdr->hdrlen + 1) << 3);
917 if (cmsg->cmsg_len < CMSG_LEN(len)) {
918 err = -EINVAL;
919 goto exit_f;
920 }
921 if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
922 err = -EPERM;
923 goto exit_f;
924 }
925 if (cmsg->cmsg_type == IPV6_DSTOPTS) {
926 opt->opt_flen += len;
927 opt->dst1opt = hdr;
928 } else {
929 opt->opt_nflen += len;
930 opt->dst0opt = hdr;
931 }
932 break;
933
934 case IPV6_2292RTHDR:
935 case IPV6_RTHDR:
936 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) {
937 err = -EINVAL;
938 goto exit_f;
939 }
940
941 rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg);
942
943 switch (rthdr->type) {
944#if IS_ENABLED(CONFIG_IPV6_MIP6)
945 case IPV6_SRCRT_TYPE_2:
946 if (rthdr->hdrlen != 2 ||
947 rthdr->segments_left != 1) {
948 err = -EINVAL;
949 goto exit_f;
950 }
951 break;
952#endif
953 default:
954 err = -EINVAL;
955 goto exit_f;
956 }
957
958 len = ((rthdr->hdrlen + 1) << 3);
959
960 if (cmsg->cmsg_len < CMSG_LEN(len)) {
961 err = -EINVAL;
962 goto exit_f;
963 }
964
965 /* segments left must also match */
966 if ((rthdr->hdrlen >> 1) != rthdr->segments_left) {
967 err = -EINVAL;
968 goto exit_f;
969 }
970
971 opt->opt_nflen += len;
972 opt->srcrt = rthdr;
973
974 if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) {
975 int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3);
976
977 opt->opt_nflen += dsthdrlen;
978 opt->dst0opt = opt->dst1opt;
979 opt->dst1opt = NULL;
980 opt->opt_flen -= dsthdrlen;
981 }
982
983 break;
984
985 case IPV6_2292HOPLIMIT:
986 case IPV6_HOPLIMIT:
987 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
988 err = -EINVAL;
989 goto exit_f;
990 }
991
992 ipc6->hlimit = *(int *)CMSG_DATA(cmsg);
993 if (ipc6->hlimit < -1 || ipc6->hlimit > 0xff) {
994 err = -EINVAL;
995 goto exit_f;
996 }
997
998 break;
999
1000 case IPV6_TCLASS:
1001 {
1002 int tc;
1003
1004 err = -EINVAL;
1005 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
1006 goto exit_f;
1007
1008 tc = *(int *)CMSG_DATA(cmsg);
1009 if (tc < -1 || tc > 0xff)
1010 goto exit_f;
1011
1012 err = 0;
1013 ipc6->tclass = tc;
1014
1015 break;
1016 }
1017
1018 case IPV6_DONTFRAG:
1019 {
1020 int df;
1021
1022 err = -EINVAL;
1023 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
1024 goto exit_f;
1025
1026 df = *(int *)CMSG_DATA(cmsg);
1027 if (df < 0 || df > 1)
1028 goto exit_f;
1029
1030 err = 0;
1031 ipc6->dontfrag = df;
1032
1033 break;
1034 }
1035 default:
1036 net_dbg_ratelimited("invalid cmsg type: %d\n",
1037 cmsg->cmsg_type);
1038 err = -EINVAL;
1039 goto exit_f;
1040 }
1041 }
1042
1043exit_f:
1044 return err;
1045}
1046EXPORT_SYMBOL_GPL(ip6_datagram_send_ctl);
1047
1048void __ip6_dgram_sock_seq_show(struct seq_file *seq, struct sock *sp,
1049 __u16 srcp, __u16 destp, int rqueue, int bucket)
1050{
1051 const struct in6_addr *dest, *src;
1052
1053 dest = &sp->sk_v6_daddr;
1054 src = &sp->sk_v6_rcv_saddr;
1055 seq_printf(seq,
1056 "%5d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1057 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %u\n",
1058 bucket,
1059 src->s6_addr32[0], src->s6_addr32[1],
1060 src->s6_addr32[2], src->s6_addr32[3], srcp,
1061 dest->s6_addr32[0], dest->s6_addr32[1],
1062 dest->s6_addr32[2], dest->s6_addr32[3], destp,
1063 sp->sk_state,
1064 sk_wmem_alloc_get(sp),
1065 rqueue,
1066 0, 0L, 0,
1067 from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)),
1068 0,
1069 sock_i_ino(sp),
1070 refcount_read(&sp->sk_refcnt), sp,
1071 atomic_read(&sp->sk_drops));
1072}