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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 <[email protected]>
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,
42 const struct sock *sk)
43{
44 const struct inet_sock *inet = inet_sk(sk);
45 const struct ipv6_pinfo *np = inet6_sk(sk);
46 int oif = sk->sk_bound_dev_if;
47
48 memset(fl6, 0, sizeof(*fl6));
49 fl6->flowi6_proto = sk->sk_protocol;
50 fl6->daddr = sk->sk_v6_daddr;
51 fl6->saddr = np->saddr;
52 fl6->flowi6_mark = sk->sk_mark;
53 fl6->fl6_dport = inet->inet_dport;
54 fl6->fl6_sport = inet->inet_sport;
55 fl6->flowlabel = ip6_make_flowinfo(np->tclass, np->flow_label);
56 fl6->flowi6_uid = sk_uid(sk);
57
58 if (!oif)
59 oif = np->sticky_pktinfo.ipi6_ifindex;
60
61 if (!oif) {
62 if (ipv6_addr_is_multicast(&fl6->daddr))
63 oif = READ_ONCE(np->mcast_oif);
64 else
65 oif = READ_ONCE(np->ucast_oif);
66 }
67
68 fl6->flowi6_oif = oif;
69 security_sk_classify_flow(sk, flowi6_to_flowi_common(fl6));
70}
71
72int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr)
73{
74 struct ip6_flowlabel *flowlabel = NULL;
75 struct inet_sock *inet = inet_sk(sk);
76 struct ipv6_pinfo *np = inet6_sk(sk);
77 struct ipv6_txoptions *opt;
78 struct in6_addr *final_p;
79 struct dst_entry *dst;
80 struct flowi6 *fl6;
81 int err = 0;
82
83 if (inet6_test_bit(SNDFLOW, sk) &&
84 (np->flow_label & IPV6_FLOWLABEL_MASK)) {
85 flowlabel = fl6_sock_lookup(sk, np->flow_label);
86 if (IS_ERR(flowlabel))
87 return -EINVAL;
88 }
89 fl6 = &inet_sk(sk)->cork.fl.u.ip6;
90 ip6_datagram_flow_key_init(fl6, sk);
91
92 rcu_read_lock();
93 opt = flowlabel ? flowlabel->opt : rcu_dereference(np->opt);
94 final_p = fl6_update_dst(fl6, opt, &np->final);
95 rcu_read_unlock();
96
97 dst = ip6_dst_lookup_flow(sock_net(sk), sk, fl6, final_p);
98 if (IS_ERR(dst)) {
99 err = PTR_ERR(dst);
100 goto out;
101 }
102
103 if (fix_sk_saddr) {
104 if (ipv6_addr_any(&np->saddr))
105 np->saddr = fl6->saddr;
106
107 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr)) {
108 sk->sk_v6_rcv_saddr = fl6->saddr;
109 inet->inet_rcv_saddr = LOOPBACK4_IPV6;
110 if (sk->sk_prot->rehash)
111 sk->sk_prot->rehash(sk);
112 }
113 }
114
115 ip6_sk_dst_store_flow(sk, dst, fl6);
116
117out:
118 fl6_sock_release(flowlabel);
119 return err;
120}
121
122void ip6_datagram_release_cb(struct sock *sk)
123{
124 struct dst_entry *dst;
125
126 if (ipv6_addr_v4mapped(&sk->sk_v6_daddr))
127 return;
128
129 rcu_read_lock();
130 dst = __sk_dst_get(sk);
131 if (!dst || !READ_ONCE(dst->obsolete) ||
132 dst->ops->check(dst, inet6_sk(sk)->dst_cookie)) {
133 rcu_read_unlock();
134 return;
135 }
136 rcu_read_unlock();
137
138 ip6_datagram_dst_update(sk, false);
139}
140EXPORT_SYMBOL_GPL(ip6_datagram_release_cb);
141
142int __ip6_datagram_connect(struct sock *sk, struct sockaddr_unsized *uaddr,
143 int addr_len)
144{
145 struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr;
146 struct inet_sock *inet = inet_sk(sk);
147 struct ipv6_pinfo *np = inet6_sk(sk);
148 struct in6_addr *daddr, old_daddr;
149 __be32 fl6_flowlabel = 0;
150 __be32 old_fl6_flowlabel;
151 __be16 old_dport;
152 int addr_type;
153 int err;
154
155 if (usin->sin6_family == AF_INET) {
156 if (ipv6_only_sock(sk))
157 return -EAFNOSUPPORT;
158 err = __ip4_datagram_connect(sk, uaddr, addr_len);
159 goto ipv4_connected;
160 }
161
162 if (addr_len < SIN6_LEN_RFC2133)
163 return -EINVAL;
164
165 if (usin->sin6_family != AF_INET6)
166 return -EAFNOSUPPORT;
167
168 if (inet6_test_bit(SNDFLOW, sk))
169 fl6_flowlabel = usin->sin6_flowinfo & IPV6_FLOWINFO_MASK;
170
171 if (ipv6_addr_any(&usin->sin6_addr)) {
172 /*
173 * connect to self
174 */
175 if (ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr))
176 ipv6_addr_set_v4mapped(htonl(INADDR_LOOPBACK),
177 &usin->sin6_addr);
178 else
179 usin->sin6_addr = in6addr_loopback;
180 }
181
182 addr_type = ipv6_addr_type(&usin->sin6_addr);
183
184 daddr = &usin->sin6_addr;
185
186 if (addr_type & IPV6_ADDR_MAPPED) {
187 struct sockaddr_in sin;
188
189 if (ipv6_only_sock(sk)) {
190 err = -ENETUNREACH;
191 goto out;
192 }
193 sin.sin_family = AF_INET;
194 sin.sin_addr.s_addr = daddr->s6_addr32[3];
195 sin.sin_port = usin->sin6_port;
196
197 err = __ip4_datagram_connect(sk,
198 (struct sockaddr_unsized *)&sin,
199 sizeof(sin));
200
201ipv4_connected:
202 if (err)
203 goto out;
204
205 ipv6_addr_set_v4mapped(inet->inet_daddr, &sk->sk_v6_daddr);
206
207 if (ipv6_addr_any(&np->saddr) ||
208 ipv6_mapped_addr_any(&np->saddr))
209 ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr);
210
211 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr) ||
212 ipv6_mapped_addr_any(&sk->sk_v6_rcv_saddr)) {
213 ipv6_addr_set_v4mapped(inet->inet_rcv_saddr,
214 &sk->sk_v6_rcv_saddr);
215 if (sk->sk_prot->rehash)
216 sk->sk_prot->rehash(sk);
217 }
218
219 goto out;
220 }
221
222 if (__ipv6_addr_needs_scope_id(addr_type)) {
223 if (addr_len >= sizeof(struct sockaddr_in6) &&
224 usin->sin6_scope_id) {
225 if (!sk_dev_equal_l3scope(sk, usin->sin6_scope_id)) {
226 err = -EINVAL;
227 goto out;
228 }
229 WRITE_ONCE(sk->sk_bound_dev_if, usin->sin6_scope_id);
230 }
231
232 if (!sk->sk_bound_dev_if && (addr_type & IPV6_ADDR_MULTICAST))
233 WRITE_ONCE(sk->sk_bound_dev_if, READ_ONCE(np->mcast_oif));
234
235 /* Connect to link-local address requires an interface */
236 if (!sk->sk_bound_dev_if) {
237 err = -EINVAL;
238 goto out;
239 }
240 }
241
242 /* save the current peer information before updating it */
243 old_daddr = sk->sk_v6_daddr;
244 old_fl6_flowlabel = np->flow_label;
245 old_dport = inet->inet_dport;
246
247 sk->sk_v6_daddr = *daddr;
248 np->flow_label = fl6_flowlabel;
249 inet->inet_dport = usin->sin6_port;
250
251 /*
252 * Check for a route to destination an obtain the
253 * destination cache for it.
254 */
255
256 err = ip6_datagram_dst_update(sk, true);
257 if (err) {
258 /* Restore the socket peer info, to keep it consistent with
259 * the old socket state
260 */
261 sk->sk_v6_daddr = old_daddr;
262 np->flow_label = old_fl6_flowlabel;
263 inet->inet_dport = old_dport;
264 goto out;
265 }
266
267 reuseport_has_conns_set(sk);
268 sk->sk_state = TCP_ESTABLISHED;
269 sk_set_txhash(sk);
270out:
271 return err;
272}
273EXPORT_SYMBOL_GPL(__ip6_datagram_connect);
274
275int ip6_datagram_connect(struct sock *sk, struct sockaddr_unsized *uaddr, int addr_len)
276{
277 int res;
278
279 lock_sock(sk);
280 res = __ip6_datagram_connect(sk, uaddr, addr_len);
281 release_sock(sk);
282 return res;
283}
284EXPORT_SYMBOL_GPL(ip6_datagram_connect);
285
286int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr_unsized *uaddr,
287 int addr_len)
288{
289 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, uaddr);
290 if (sin6->sin6_family != AF_INET6)
291 return -EAFNOSUPPORT;
292 return ip6_datagram_connect(sk, uaddr, addr_len);
293}
294EXPORT_SYMBOL_GPL(ip6_datagram_connect_v6_only);
295
296static void ipv6_icmp_error_rfc4884(const struct sk_buff *skb,
297 struct sock_ee_data_rfc4884 *out)
298{
299 switch (icmp6_hdr(skb)->icmp6_type) {
300 case ICMPV6_TIME_EXCEED:
301 case ICMPV6_DEST_UNREACH:
302 ip_icmp_error_rfc4884(skb, out, sizeof(struct icmp6hdr),
303 icmp6_hdr(skb)->icmp6_datagram_len * 8);
304 }
305}
306
307void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
308 __be16 port, u32 info, u8 *payload)
309{
310 struct icmp6hdr *icmph = icmp6_hdr(skb);
311 struct sock_exterr_skb *serr;
312
313 if (!inet6_test_bit(RECVERR6, sk))
314 return;
315
316 skb = skb_clone(skb, GFP_ATOMIC);
317 if (!skb)
318 return;
319
320 skb->protocol = htons(ETH_P_IPV6);
321
322 serr = SKB_EXT_ERR(skb);
323 serr->ee.ee_errno = err;
324 serr->ee.ee_origin = SO_EE_ORIGIN_ICMP6;
325 serr->ee.ee_type = icmph->icmp6_type;
326 serr->ee.ee_code = icmph->icmp6_code;
327 serr->ee.ee_pad = 0;
328 serr->ee.ee_info = info;
329 serr->ee.ee_data = 0;
330 serr->addr_offset = (u8 *)&(((struct ipv6hdr *)(icmph + 1))->daddr) -
331 skb_network_header(skb);
332 serr->port = port;
333
334 __skb_pull(skb, payload - skb->data);
335
336 if (inet6_test_bit(RECVERR6_RFC4884, sk))
337 ipv6_icmp_error_rfc4884(skb, &serr->ee.ee_rfc4884);
338
339 skb_reset_transport_header(skb);
340
341 if (sock_queue_err_skb(sk, skb))
342 kfree_skb(skb);
343}
344EXPORT_SYMBOL_GPL(ipv6_icmp_error);
345
346void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info)
347{
348 struct sock_exterr_skb *serr;
349 struct ipv6hdr *iph;
350 struct sk_buff *skb;
351
352 if (!inet6_test_bit(RECVERR6, sk))
353 return;
354
355 skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
356 if (!skb)
357 return;
358
359 skb->protocol = htons(ETH_P_IPV6);
360
361 skb_put(skb, sizeof(struct ipv6hdr));
362 skb_reset_network_header(skb);
363 iph = ipv6_hdr(skb);
364 iph->daddr = fl6->daddr;
365 ip6_flow_hdr(iph, 0, 0);
366
367 serr = SKB_EXT_ERR(skb);
368 serr->ee.ee_errno = err;
369 serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
370 serr->ee.ee_type = 0;
371 serr->ee.ee_code = 0;
372 serr->ee.ee_pad = 0;
373 serr->ee.ee_info = info;
374 serr->ee.ee_data = 0;
375 serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
376 serr->port = fl6->fl6_dport;
377
378 __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
379 skb_reset_transport_header(skb);
380
381 if (sock_queue_err_skb(sk, skb))
382 kfree_skb(skb);
383}
384
385void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu)
386{
387 struct ipv6_pinfo *np = inet6_sk(sk);
388 struct ipv6hdr *iph;
389 struct sk_buff *skb;
390 struct ip6_mtuinfo *mtu_info;
391
392 if (!np->rxopt.bits.rxpmtu)
393 return;
394
395 skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
396 if (!skb)
397 return;
398
399 skb_put(skb, sizeof(struct ipv6hdr));
400 skb_reset_network_header(skb);
401 iph = ipv6_hdr(skb);
402 iph->daddr = fl6->daddr;
403
404 mtu_info = IP6CBMTU(skb);
405
406 mtu_info->ip6m_mtu = mtu;
407 mtu_info->ip6m_addr.sin6_family = AF_INET6;
408 mtu_info->ip6m_addr.sin6_port = 0;
409 mtu_info->ip6m_addr.sin6_flowinfo = 0;
410 mtu_info->ip6m_addr.sin6_scope_id = fl6->flowi6_oif;
411 mtu_info->ip6m_addr.sin6_addr = ipv6_hdr(skb)->daddr;
412
413 __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
414 skb_reset_transport_header(skb);
415
416 skb = xchg(&np->rxpmtu, skb);
417 kfree_skb(skb);
418}
419
420/* For some errors we have valid addr_offset even with zero payload and
421 * zero port. Also, addr_offset should be supported if port is set.
422 */
423static inline bool ipv6_datagram_support_addr(struct sock_exterr_skb *serr)
424{
425 return serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6 ||
426 serr->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
427 serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL || serr->port;
428}
429
430/* IPv6 supports cmsg on all origins aside from SO_EE_ORIGIN_LOCAL.
431 *
432 * At one point, excluding local errors was a quick test to identify icmp/icmp6
433 * errors. This is no longer true, but the test remained, so the v6 stack,
434 * unlike v4, also honors cmsg requests on all wifi and timestamp errors.
435 */
436static bool ip6_datagram_support_cmsg(struct sk_buff *skb,
437 struct sock_exterr_skb *serr)
438{
439 if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
440 serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6)
441 return true;
442
443 if (serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL)
444 return false;
445
446 if (!IP6CB(skb)->iif)
447 return false;
448
449 return true;
450}
451
452/*
453 * Handle MSG_ERRQUEUE
454 */
455int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len)
456{
457 struct ipv6_pinfo *np = inet6_sk(sk);
458 struct sock_exterr_skb *serr;
459 struct sk_buff *skb;
460 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name);
461 struct {
462 struct sock_extended_err ee;
463 struct sockaddr_in6 offender;
464 } errhdr;
465 int err;
466 int copied;
467
468 err = -EAGAIN;
469 skb = sock_dequeue_err_skb(sk);
470 if (!skb)
471 goto out;
472
473 copied = skb->len;
474 if (copied > len) {
475 msg->msg_flags |= MSG_TRUNC;
476 copied = len;
477 }
478 err = skb_copy_datagram_msg(skb, 0, msg, copied);
479 if (unlikely(err)) {
480 kfree_skb(skb);
481 return err;
482 }
483 sock_recv_timestamp(msg, sk, skb);
484
485 serr = SKB_EXT_ERR(skb);
486
487 if (sin && ipv6_datagram_support_addr(serr)) {
488 const unsigned char *nh = skb_network_header(skb);
489 sin->sin6_family = AF_INET6;
490 sin->sin6_flowinfo = 0;
491 sin->sin6_port = serr->port;
492 if (skb->protocol == htons(ETH_P_IPV6)) {
493 const struct ipv6hdr *ip6h = container_of((struct in6_addr *)(nh + serr->addr_offset),
494 struct ipv6hdr, daddr);
495 sin->sin6_addr = ip6h->daddr;
496 if (inet6_test_bit(SNDFLOW, sk))
497 sin->sin6_flowinfo = ip6_flowinfo(ip6h);
498 sin->sin6_scope_id =
499 ipv6_iface_scope_id(&sin->sin6_addr,
500 IP6CB(skb)->iif);
501 } else {
502 ipv6_addr_set_v4mapped(*(__be32 *)(nh + serr->addr_offset),
503 &sin->sin6_addr);
504 sin->sin6_scope_id = 0;
505 }
506 msg->msg_namelen = sizeof(*sin);
507 }
508
509 memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
510 sin = &errhdr.offender;
511 memset(sin, 0, sizeof(*sin));
512
513 if (ip6_datagram_support_cmsg(skb, serr)) {
514 sin->sin6_family = AF_INET6;
515 if (np->rxopt.all)
516 ip6_datagram_recv_common_ctl(sk, msg, skb);
517 if (skb->protocol == htons(ETH_P_IPV6)) {
518 sin->sin6_addr = ipv6_hdr(skb)->saddr;
519 if (np->rxopt.all)
520 ip6_datagram_recv_specific_ctl(sk, msg, skb);
521 sin->sin6_scope_id =
522 ipv6_iface_scope_id(&sin->sin6_addr,
523 IP6CB(skb)->iif);
524 } else {
525 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
526 &sin->sin6_addr);
527 if (inet_cmsg_flags(inet_sk(sk)))
528 ip_cmsg_recv(msg, skb);
529 }
530 }
531
532 put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr);
533
534 /* Now we could try to dump offended packet options */
535
536 msg->msg_flags |= MSG_ERRQUEUE;
537 err = copied;
538
539 consume_skb(skb);
540out:
541 return err;
542}
543EXPORT_SYMBOL_GPL(ipv6_recv_error);
544
545/*
546 * Handle IPV6_RECVPATHMTU
547 */
548int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int 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 msg->msg_namelen = 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
620static u16 ipv6_get_exthdr_len(const struct sk_buff *skb, const u8 *ptr)
621{
622 u16 len;
623
624 if (ptr + 2 > skb_tail_pointer(skb))
625 return 0;
626
627 len = (ptr[1] + 1) << 3;
628
629 return (len <= skb_tail_pointer(skb) - ptr) ? len : 0;
630}
631
632void ip6_datagram_recv_specific_ctl(struct sock *sk, struct msghdr *msg,
633 struct sk_buff *skb)
634{
635 struct ipv6_pinfo *np = inet6_sk(sk);
636 struct inet6_skb_parm *opt = IP6CB(skb);
637 unsigned char *nh = skb_network_header(skb);
638
639 if (np->rxopt.bits.rxhlim) {
640 int hlim = ipv6_hdr(skb)->hop_limit;
641 put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
642 }
643
644 if (np->rxopt.bits.rxtclass) {
645 int tclass = ipv6_get_dsfield(ipv6_hdr(skb));
646 put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
647 }
648
649 if (np->rxopt.bits.rxflow) {
650 __be32 flowinfo = ip6_flowinfo((struct ipv6hdr *)nh);
651 if (flowinfo)
652 put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
653 }
654
655 /* HbH is allowed only once */
656 if (np->rxopt.bits.hopopts && (opt->flags & IP6SKB_HOPBYHOP)) {
657 u8 *ptr = nh + sizeof(struct ipv6hdr);
658 u16 len = ipv6_get_exthdr_len(skb, ptr);
659
660 if (len)
661 put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, len, ptr);
662 }
663
664 if (opt->lastopt &&
665 (np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) {
666 /*
667 * Silly enough, but we need to reparse in order to
668 * report extension headers (except for HbH)
669 * in order.
670 *
671 * Also note that IPV6_RECVRTHDRDSTOPTS is NOT
672 * (and WILL NOT be) defined because
673 * IPV6_RECVDSTOPTS is more generic. --yoshfuji
674 */
675 unsigned int off = sizeof(struct ipv6hdr);
676 u8 nexthdr = ipv6_hdr(skb)->nexthdr;
677
678 while (off <= opt->lastopt) {
679 unsigned int len;
680 u8 *ptr = nh + off;
681
682 if (ptr + 2 > skb_tail_pointer(skb))
683 return;
684
685 switch (nexthdr) {
686 case IPPROTO_DSTOPTS:
687 nexthdr = ptr[0];
688 len = ipv6_get_exthdr_len(skb, ptr);
689 if (!len)
690 return;
691 if (np->rxopt.bits.dstopts)
692 put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, ptr);
693 break;
694 case IPPROTO_ROUTING:
695 nexthdr = ptr[0];
696 len = ipv6_get_exthdr_len(skb, ptr);
697 if (!len)
698 return;
699 if (np->rxopt.bits.srcrt)
700 put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, ptr);
701 break;
702 case IPPROTO_AH:
703 nexthdr = ptr[0];
704 len = (ptr[1] + 2) << 2;
705 if (ptr + len > skb_tail_pointer(skb))
706 return;
707 break;
708 default:
709 nexthdr = ptr[0];
710 len = ipv6_get_exthdr_len(skb, ptr);
711 if (!len)
712 return;
713 break;
714 }
715
716 off += len;
717 }
718 }
719
720 /* socket options in old style */
721 if (np->rxopt.bits.rxoinfo) {
722 struct in6_pktinfo src_info;
723
724 src_info.ipi6_ifindex = opt->iif;
725 src_info.ipi6_addr = ipv6_hdr(skb)->daddr;
726 put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
727 }
728 if (np->rxopt.bits.rxohlim) {
729 int hlim = ipv6_hdr(skb)->hop_limit;
730 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
731 }
732 if (np->rxopt.bits.ohopopts && (opt->flags & IP6SKB_HOPBYHOP)) {
733 u8 *ptr = nh + sizeof(struct ipv6hdr);
734 u16 len = ipv6_get_exthdr_len(skb, ptr);
735
736 if (len)
737 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, len, ptr);
738 }
739 if (np->rxopt.bits.odstopts && opt->dst0) {
740 u8 *ptr = nh + opt->dst0;
741 u16 len = ipv6_get_exthdr_len(skb, ptr);
742
743 if (len)
744 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, len, ptr);
745 }
746 if (np->rxopt.bits.osrcrt && opt->srcrt) {
747 struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt);
748 u16 len = ipv6_get_exthdr_len(skb, (u8 *)rthdr);
749
750 if (len)
751 put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, len, rthdr);
752 }
753 if (np->rxopt.bits.odstopts && opt->dst1) {
754 u8 *ptr = nh + opt->dst1;
755 u16 len = ipv6_get_exthdr_len(skb, ptr);
756
757 if (len)
758 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, len, ptr);
759 }
760 if (np->rxopt.bits.rxorigdstaddr) {
761 struct sockaddr_in6 sin6;
762 __be16 _ports[2], *ports;
763
764 ports = skb_header_pointer(skb, skb_transport_offset(skb),
765 sizeof(_ports), &_ports);
766 if (ports) {
767 /* All current transport protocols have the port numbers in the
768 * first four bytes of the transport header and this function is
769 * written with this assumption in mind.
770 */
771 sin6.sin6_family = AF_INET6;
772 sin6.sin6_addr = ipv6_hdr(skb)->daddr;
773 sin6.sin6_port = ports[1];
774 sin6.sin6_flowinfo = 0;
775 sin6.sin6_scope_id =
776 ipv6_iface_scope_id(&ipv6_hdr(skb)->daddr,
777 opt->iif);
778
779 put_cmsg(msg, SOL_IPV6, IPV6_ORIGDSTADDR, sizeof(sin6), &sin6);
780 }
781 }
782 if (np->rxopt.bits.recvfragsize && opt->frag_max_size) {
783 int val = opt->frag_max_size;
784
785 put_cmsg(msg, SOL_IPV6, IPV6_RECVFRAGSIZE, sizeof(val), &val);
786 }
787}
788
789void ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg,
790 struct sk_buff *skb)
791{
792 ip6_datagram_recv_common_ctl(sk, msg, skb);
793 ip6_datagram_recv_specific_ctl(sk, msg, skb);
794}
795EXPORT_SYMBOL_GPL(ip6_datagram_recv_ctl);
796
797int ip6_datagram_send_ctl(struct net *net, struct sock *sk,
798 struct msghdr *msg, struct flowi6 *fl6,
799 struct ipcm6_cookie *ipc6)
800{
801 struct in6_pktinfo *src_info;
802 struct cmsghdr *cmsg;
803 struct ipv6_rt_hdr *orthdr;
804 struct ipv6_rt_hdr *rthdr;
805 struct ipv6_opt_hdr *hdr;
806 struct ipv6_txoptions *opt = ipc6->opt;
807 int len;
808 int err = 0;
809
810 for_each_cmsghdr(cmsg, msg) {
811 int addr_type;
812
813 if (!CMSG_OK(msg, cmsg)) {
814 err = -EINVAL;
815 goto exit_f;
816 }
817
818 if (cmsg->cmsg_level == SOL_SOCKET) {
819 err = __sock_cmsg_send(sk, cmsg, &ipc6->sockc);
820 if (err)
821 return err;
822 continue;
823 }
824
825 if (cmsg->cmsg_level != SOL_IPV6)
826 continue;
827
828 switch (cmsg->cmsg_type) {
829 case IPV6_PKTINFO:
830 case IPV6_2292PKTINFO:
831 {
832 struct net_device *dev = NULL;
833 int src_idx;
834
835 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) {
836 err = -EINVAL;
837 goto exit_f;
838 }
839
840 src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
841 src_idx = src_info->ipi6_ifindex;
842
843 if (src_idx) {
844 if (fl6->flowi6_oif &&
845 src_idx != fl6->flowi6_oif &&
846 (READ_ONCE(sk->sk_bound_dev_if) != fl6->flowi6_oif ||
847 !sk_dev_equal_l3scope(sk, src_idx)))
848 return -EINVAL;
849 fl6->flowi6_oif = src_idx;
850 }
851
852 addr_type = __ipv6_addr_type(&src_info->ipi6_addr);
853
854 rcu_read_lock();
855 if (fl6->flowi6_oif) {
856 dev = dev_get_by_index_rcu(net, fl6->flowi6_oif);
857 if (!dev) {
858 rcu_read_unlock();
859 return -ENODEV;
860 }
861 } else if (addr_type & IPV6_ADDR_LINKLOCAL) {
862 rcu_read_unlock();
863 return -EINVAL;
864 }
865
866 if (addr_type != IPV6_ADDR_ANY) {
867 int strict = __ipv6_addr_src_scope(addr_type) <= IPV6_ADDR_SCOPE_LINKLOCAL;
868 if (!ipv6_can_nonlocal_bind(net, inet_sk(sk)) &&
869 !ipv6_chk_addr_and_flags(net, &src_info->ipi6_addr,
870 dev, !strict, 0,
871 IFA_F_TENTATIVE) &&
872 !ipv6_chk_acast_addr_src(net, dev,
873 &src_info->ipi6_addr))
874 err = -EINVAL;
875 else
876 fl6->saddr = src_info->ipi6_addr;
877 }
878
879 rcu_read_unlock();
880
881 if (err)
882 goto exit_f;
883
884 break;
885 }
886
887 case IPV6_FLOWINFO:
888 if (cmsg->cmsg_len < CMSG_LEN(4)) {
889 err = -EINVAL;
890 goto exit_f;
891 }
892
893 if (fl6->flowlabel&IPV6_FLOWINFO_MASK) {
894 if ((fl6->flowlabel^*(__be32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) {
895 err = -EINVAL;
896 goto exit_f;
897 }
898 }
899 fl6->flowlabel = IPV6_FLOWINFO_MASK & *(__be32 *)CMSG_DATA(cmsg);
900 break;
901
902 case IPV6_2292HOPOPTS:
903 case IPV6_HOPOPTS:
904 if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
905 err = -EINVAL;
906 goto exit_f;
907 }
908
909 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
910 len = ((hdr->hdrlen + 1) << 3);
911 if (cmsg->cmsg_len < CMSG_LEN(len)) {
912 err = -EINVAL;
913 goto exit_f;
914 }
915 if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
916 err = -EPERM;
917 goto exit_f;
918 }
919 opt->opt_nflen += len;
920 opt->hopopt = hdr;
921 break;
922
923 case IPV6_2292DSTOPTS:
924 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
925 err = -EINVAL;
926 goto exit_f;
927 }
928
929 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
930 len = ((hdr->hdrlen + 1) << 3);
931 if (cmsg->cmsg_len < CMSG_LEN(len)) {
932 err = -EINVAL;
933 goto exit_f;
934 }
935 if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
936 err = -EPERM;
937 goto exit_f;
938 }
939 if (opt->dst1opt) {
940 err = -EINVAL;
941 goto exit_f;
942 }
943 opt->opt_flen += len;
944 opt->dst1opt = hdr;
945 break;
946
947 case IPV6_DSTOPTS:
948 case IPV6_RTHDRDSTOPTS:
949 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
950 err = -EINVAL;
951 goto exit_f;
952 }
953
954 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
955 len = ((hdr->hdrlen + 1) << 3);
956 if (cmsg->cmsg_len < CMSG_LEN(len)) {
957 err = -EINVAL;
958 goto exit_f;
959 }
960 if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
961 err = -EPERM;
962 goto exit_f;
963 }
964 if (cmsg->cmsg_type == IPV6_DSTOPTS) {
965 if (opt->dst1opt)
966 opt->opt_flen -= ipv6_optlen(opt->dst1opt);
967 opt->opt_flen += len;
968 opt->dst1opt = hdr;
969 } else {
970 if (opt->dst0opt)
971 opt->opt_nflen -= ipv6_optlen(opt->dst0opt);
972 opt->opt_nflen += len;
973 opt->dst0opt = hdr;
974 }
975 break;
976
977 case IPV6_2292RTHDR:
978 case IPV6_RTHDR:
979 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) {
980 err = -EINVAL;
981 goto exit_f;
982 }
983
984 rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg);
985
986 switch (rthdr->type) {
987#if IS_ENABLED(CONFIG_IPV6_MIP6)
988 case IPV6_SRCRT_TYPE_2:
989 if (rthdr->hdrlen != 2 ||
990 rthdr->segments_left != 1) {
991 err = -EINVAL;
992 goto exit_f;
993 }
994 break;
995#endif
996 default:
997 err = -EINVAL;
998 goto exit_f;
999 }
1000
1001 len = ((rthdr->hdrlen + 1) << 3);
1002
1003 if (cmsg->cmsg_len < CMSG_LEN(len)) {
1004 err = -EINVAL;
1005 goto exit_f;
1006 }
1007
1008 /* segments left must also match */
1009 if ((rthdr->hdrlen >> 1) != rthdr->segments_left) {
1010 err = -EINVAL;
1011 goto exit_f;
1012 }
1013
1014 orthdr = opt->srcrt;
1015 if (orthdr)
1016 opt->opt_nflen -= ((orthdr->hdrlen + 1) << 3);
1017 opt->opt_nflen += len;
1018 opt->srcrt = rthdr;
1019
1020 if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) {
1021 int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3);
1022
1023 if (opt->dst0opt)
1024 opt->opt_nflen -= ipv6_optlen(opt->dst0opt);
1025 opt->opt_nflen += dsthdrlen;
1026 opt->dst0opt = opt->dst1opt;
1027 opt->dst1opt = NULL;
1028 opt->opt_flen -= dsthdrlen;
1029 }
1030
1031 break;
1032
1033 case IPV6_2292HOPLIMIT:
1034 case IPV6_HOPLIMIT:
1035 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
1036 err = -EINVAL;
1037 goto exit_f;
1038 }
1039
1040 ipc6->hlimit = *(int *)CMSG_DATA(cmsg);
1041 if (ipc6->hlimit < -1 || ipc6->hlimit > 0xff) {
1042 err = -EINVAL;
1043 goto exit_f;
1044 }
1045
1046 break;
1047
1048 case IPV6_TCLASS:
1049 {
1050 int tc;
1051
1052 err = -EINVAL;
1053 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
1054 goto exit_f;
1055
1056 tc = *(int *)CMSG_DATA(cmsg);
1057 if (tc < -1 || tc > 0xff)
1058 goto exit_f;
1059
1060 err = 0;
1061 ipc6->tclass = tc;
1062
1063 break;
1064 }
1065
1066 case IPV6_DONTFRAG:
1067 {
1068 int df;
1069
1070 err = -EINVAL;
1071 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
1072 goto exit_f;
1073
1074 df = *(int *)CMSG_DATA(cmsg);
1075 if (df < 0 || df > 1)
1076 goto exit_f;
1077
1078 err = 0;
1079 ipc6->dontfrag = df;
1080
1081 break;
1082 }
1083 default:
1084 net_dbg_ratelimited("invalid cmsg type: %d\n",
1085 cmsg->cmsg_type);
1086 err = -EINVAL;
1087 goto exit_f;
1088 }
1089 }
1090
1091exit_f:
1092 return err;
1093}
1094EXPORT_SYMBOL_GPL(ip6_datagram_send_ctl);
1095
1096void __ip6_dgram_sock_seq_show(struct seq_file *seq, struct sock *sp,
1097 __u16 srcp, __u16 destp, int rqueue, int bucket)
1098{
1099 const struct in6_addr *dest, *src;
1100
1101 dest = &sp->sk_v6_daddr;
1102 src = &sp->sk_v6_rcv_saddr;
1103 seq_printf(seq,
1104 "%5d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1105 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %llu %d %pK %u\n",
1106 bucket,
1107 src->s6_addr32[0], src->s6_addr32[1],
1108 src->s6_addr32[2], src->s6_addr32[3], srcp,
1109 dest->s6_addr32[0], dest->s6_addr32[1],
1110 dest->s6_addr32[2], dest->s6_addr32[3], destp,
1111 sp->sk_state,
1112 sk_wmem_alloc_get(sp),
1113 rqueue,
1114 0, 0L, 0,
1115 from_kuid_munged(seq_user_ns(seq), sk_uid(sp)),
1116 0,
1117 sock_i_ino(sp),
1118 refcount_read(&sp->sk_refcnt), sp,
1119 sk_drops_read(sp));
1120}