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