1 /*
2 * common UDP/RAW code
3 * Linux INET6 implementation
4 *
5 * Authors:
6 * Pedro Roque <roque@di.fc.ul.pt>
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * as published by the Free Software Foundation; either version
11 * 2 of the License, or (at your option) any later version.
12 */
13
14 #include <linux/capability.h>
15 #include <linux/errno.h>
16 #include <linux/types.h>
17 #include <linux/kernel.h>
18 #include <linux/interrupt.h>
19 #include <linux/socket.h>
20 #include <linux/sockios.h>
21 #include <linux/in6.h>
22 #include <linux/ipv6.h>
23 #include <linux/route.h>
24 #include <linux/slab.h>
25 #include <linux/export.h>
26
27 #include <net/ipv6.h>
28 #include <net/ndisc.h>
29 #include <net/addrconf.h>
30 #include <net/transp_v6.h>
31 #include <net/ip6_route.h>
32 #include <net/tcp_states.h>
33 #include <net/dsfield.h>
34
35 #include <linux/errqueue.h>
36 #include <asm/uaccess.h>
37
ipv6_mapped_addr_any(const struct in6_addr * a)38 static bool ipv6_mapped_addr_any(const struct in6_addr *a)
39 {
40 return ipv6_addr_v4mapped(a) && (a->s6_addr32[3] == 0);
41 }
42
ip6_datagram_flow_key_init(struct flowi6 * fl6,struct sock * sk)43 static void ip6_datagram_flow_key_init(struct flowi6 *fl6, struct sock *sk)
44 {
45 struct inet_sock *inet = inet_sk(sk);
46 struct ipv6_pinfo *np = inet6_sk(sk);
47
48 memset(fl6, 0, sizeof(*fl6));
49 fl6->flowi6_proto = sk->sk_protocol;
50 fl6->daddr = sk->sk_v6_daddr;
51 fl6->saddr = np->saddr;
52 fl6->flowi6_oif = sk->sk_bound_dev_if;
53 fl6->flowi6_mark = sk->sk_mark;
54 fl6->fl6_dport = inet->inet_dport;
55 fl6->fl6_sport = inet->inet_sport;
56 fl6->flowlabel = np->flow_label;
57 fl6->flowi6_uid = sk->sk_uid;
58
59 if (!fl6->flowi6_oif)
60 fl6->flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
61
62 if (!fl6->flowi6_oif && ipv6_addr_is_multicast(&fl6->daddr))
63 fl6->flowi6_oif = np->mcast_oif;
64
65 security_sk_classify_flow(sk, flowi6_to_flowi(fl6));
66 }
67
ip6_datagram_dst_update(struct sock * sk,bool fix_sk_saddr)68 int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr)
69 {
70 struct ip6_flowlabel *flowlabel = NULL;
71 struct in6_addr *final_p, final;
72 struct ipv6_txoptions *opt;
73 struct dst_entry *dst;
74 struct inet_sock *inet = inet_sk(sk);
75 struct ipv6_pinfo *np = inet6_sk(sk);
76 struct flowi6 fl6;
77 int err = 0;
78
79 if (np->sndflow && (np->flow_label & IPV6_FLOWLABEL_MASK)) {
80 flowlabel = fl6_sock_lookup(sk, np->flow_label);
81 if (!flowlabel)
82 return -EINVAL;
83 }
84 ip6_datagram_flow_key_init(&fl6, sk);
85
86 rcu_read_lock();
87 opt = flowlabel ? flowlabel->opt : rcu_dereference(np->opt);
88 final_p = fl6_update_dst(&fl6, opt, &final);
89 rcu_read_unlock();
90
91 dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
92 if (IS_ERR(dst)) {
93 err = PTR_ERR(dst);
94 goto out;
95 }
96
97 if (fix_sk_saddr) {
98 if (ipv6_addr_any(&np->saddr))
99 np->saddr = fl6.saddr;
100
101 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr)) {
102 sk->sk_v6_rcv_saddr = fl6.saddr;
103 inet->inet_rcv_saddr = LOOPBACK4_IPV6;
104 if (sk->sk_prot->rehash)
105 sk->sk_prot->rehash(sk);
106 }
107 }
108
109 ip6_dst_store(sk, dst,
110 ipv6_addr_equal(&fl6.daddr, &sk->sk_v6_daddr) ?
111 &sk->sk_v6_daddr : NULL,
112 #ifdef CONFIG_IPV6_SUBTREES
113 ipv6_addr_equal(&fl6.saddr, &np->saddr) ?
114 &np->saddr :
115 #endif
116 NULL);
117
118 out:
119 fl6_sock_release(flowlabel);
120 return err;
121 }
122
ip6_datagram_release_cb(struct sock * sk)123 void ip6_datagram_release_cb(struct sock *sk)
124 {
125 struct dst_entry *dst;
126
127 if (ipv6_addr_v4mapped(&sk->sk_v6_daddr))
128 return;
129
130 rcu_read_lock();
131 dst = __sk_dst_get(sk);
132 if (!dst || !dst->obsolete ||
133 dst->ops->check(dst, inet6_sk(sk)->dst_cookie)) {
134 rcu_read_unlock();
135 return;
136 }
137 rcu_read_unlock();
138
139 ip6_datagram_dst_update(sk, false);
140 }
141 EXPORT_SYMBOL_GPL(ip6_datagram_release_cb);
142
__ip6_datagram_connect(struct sock * sk,struct sockaddr * uaddr,int addr_len)143 int __ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr,
144 int addr_len)
145 {
146 struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr;
147 struct inet_sock *inet = inet_sk(sk);
148 struct ipv6_pinfo *np = inet6_sk(sk);
149 struct in6_addr *daddr;
150 int addr_type;
151 int err;
152 __be32 fl6_flowlabel = 0;
153
154 if (usin->sin6_family == AF_INET) {
155 if (__ipv6_only_sock(sk))
156 return -EAFNOSUPPORT;
157 err = __ip4_datagram_connect(sk, uaddr, addr_len);
158 goto ipv4_connected;
159 }
160
161 if (addr_len < SIN6_LEN_RFC2133)
162 return -EINVAL;
163
164 if (usin->sin6_family != AF_INET6)
165 return -EAFNOSUPPORT;
166
167 if (np->sndflow)
168 fl6_flowlabel = usin->sin6_flowinfo & IPV6_FLOWINFO_MASK;
169
170 if (ipv6_addr_any(&usin->sin6_addr)) {
171 /*
172 * connect to self
173 */
174 if (ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr))
175 ipv6_addr_set_v4mapped(htonl(INADDR_LOOPBACK),
176 &usin->sin6_addr);
177 else
178 usin->sin6_addr = in6addr_loopback;
179 }
180
181 addr_type = ipv6_addr_type(&usin->sin6_addr);
182
183 daddr = &usin->sin6_addr;
184
185 if (addr_type & IPV6_ADDR_MAPPED) {
186 struct sockaddr_in sin;
187
188 if (__ipv6_only_sock(sk)) {
189 err = -ENETUNREACH;
190 goto out;
191 }
192 sin.sin_family = AF_INET;
193 sin.sin_addr.s_addr = daddr->s6_addr32[3];
194 sin.sin_port = usin->sin6_port;
195
196 err = __ip4_datagram_connect(sk,
197 (struct sockaddr *) &sin,
198 sizeof(sin));
199
200 ipv4_connected:
201 if (err)
202 goto out;
203
204 ipv6_addr_set_v4mapped(inet->inet_daddr, &sk->sk_v6_daddr);
205
206 if (ipv6_addr_any(&np->saddr) ||
207 ipv6_mapped_addr_any(&np->saddr))
208 ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr);
209
210 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr) ||
211 ipv6_mapped_addr_any(&sk->sk_v6_rcv_saddr)) {
212 ipv6_addr_set_v4mapped(inet->inet_rcv_saddr,
213 &sk->sk_v6_rcv_saddr);
214 if (sk->sk_prot->rehash)
215 sk->sk_prot->rehash(sk);
216 }
217
218 goto out;
219 }
220
221 if (__ipv6_addr_needs_scope_id(addr_type)) {
222 if (addr_len >= sizeof(struct sockaddr_in6) &&
223 usin->sin6_scope_id) {
224 if (sk->sk_bound_dev_if &&
225 sk->sk_bound_dev_if != usin->sin6_scope_id) {
226 err = -EINVAL;
227 goto out;
228 }
229 sk->sk_bound_dev_if = usin->sin6_scope_id;
230 }
231
232 if (!sk->sk_bound_dev_if && (addr_type & IPV6_ADDR_MULTICAST))
233 sk->sk_bound_dev_if = np->mcast_oif;
234
235 /* Connect to link-local address requires an interface */
236 if (!sk->sk_bound_dev_if) {
237 err = -EINVAL;
238 goto out;
239 }
240 }
241
242 sk->sk_v6_daddr = *daddr;
243 np->flow_label = fl6_flowlabel;
244
245 inet->inet_dport = usin->sin6_port;
246
247 /*
248 * Check for a route to destination an obtain the
249 * destination cache for it.
250 */
251
252 err = ip6_datagram_dst_update(sk, true);
253 if (err)
254 goto out;
255
256 sk->sk_state = TCP_ESTABLISHED;
257 sk_set_txhash(sk);
258 out:
259 return err;
260 }
261 EXPORT_SYMBOL_GPL(__ip6_datagram_connect);
262
ip6_datagram_connect(struct sock * sk,struct sockaddr * uaddr,int addr_len)263 int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
264 {
265 int res;
266
267 lock_sock(sk);
268 res = __ip6_datagram_connect(sk, uaddr, addr_len);
269 release_sock(sk);
270 return res;
271 }
272 EXPORT_SYMBOL_GPL(ip6_datagram_connect);
273
ip6_datagram_connect_v6_only(struct sock * sk,struct sockaddr * uaddr,int addr_len)274 int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *uaddr,
275 int addr_len)
276 {
277 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, uaddr);
278 if (sin6->sin6_family != AF_INET6)
279 return -EAFNOSUPPORT;
280 return ip6_datagram_connect(sk, uaddr, addr_len);
281 }
282 EXPORT_SYMBOL_GPL(ip6_datagram_connect_v6_only);
283
ipv6_icmp_error(struct sock * sk,struct sk_buff * skb,int err,__be16 port,u32 info,u8 * payload)284 void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
285 __be16 port, u32 info, u8 *payload)
286 {
287 struct ipv6_pinfo *np = inet6_sk(sk);
288 struct icmp6hdr *icmph = icmp6_hdr(skb);
289 struct sock_exterr_skb *serr;
290
291 if (!np->recverr)
292 return;
293
294 skb = skb_clone(skb, GFP_ATOMIC);
295 if (!skb)
296 return;
297
298 skb->protocol = htons(ETH_P_IPV6);
299
300 serr = SKB_EXT_ERR(skb);
301 serr->ee.ee_errno = err;
302 serr->ee.ee_origin = SO_EE_ORIGIN_ICMP6;
303 serr->ee.ee_type = icmph->icmp6_type;
304 serr->ee.ee_code = icmph->icmp6_code;
305 serr->ee.ee_pad = 0;
306 serr->ee.ee_info = info;
307 serr->ee.ee_data = 0;
308 serr->addr_offset = (u8 *)&(((struct ipv6hdr *)(icmph + 1))->daddr) -
309 skb_network_header(skb);
310 serr->port = port;
311
312 __skb_pull(skb, payload - skb->data);
313 skb_reset_transport_header(skb);
314
315 if (sock_queue_err_skb(sk, skb))
316 kfree_skb(skb);
317 }
318
ipv6_local_error(struct sock * sk,int err,struct flowi6 * fl6,u32 info)319 void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info)
320 {
321 const struct ipv6_pinfo *np = inet6_sk(sk);
322 struct sock_exterr_skb *serr;
323 struct ipv6hdr *iph;
324 struct sk_buff *skb;
325
326 if (!np->recverr)
327 return;
328
329 skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
330 if (!skb)
331 return;
332
333 skb->protocol = htons(ETH_P_IPV6);
334
335 skb_put(skb, sizeof(struct ipv6hdr));
336 skb_reset_network_header(skb);
337 iph = ipv6_hdr(skb);
338 iph->daddr = fl6->daddr;
339
340 serr = SKB_EXT_ERR(skb);
341 serr->ee.ee_errno = err;
342 serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
343 serr->ee.ee_type = 0;
344 serr->ee.ee_code = 0;
345 serr->ee.ee_pad = 0;
346 serr->ee.ee_info = info;
347 serr->ee.ee_data = 0;
348 serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
349 serr->port = fl6->fl6_dport;
350
351 __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
352 skb_reset_transport_header(skb);
353
354 if (sock_queue_err_skb(sk, skb))
355 kfree_skb(skb);
356 }
357
ipv6_local_rxpmtu(struct sock * sk,struct flowi6 * fl6,u32 mtu)358 void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu)
359 {
360 struct ipv6_pinfo *np = inet6_sk(sk);
361 struct ipv6hdr *iph;
362 struct sk_buff *skb;
363 struct ip6_mtuinfo *mtu_info;
364
365 if (!np->rxopt.bits.rxpmtu)
366 return;
367
368 skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
369 if (!skb)
370 return;
371
372 skb_put(skb, sizeof(struct ipv6hdr));
373 skb_reset_network_header(skb);
374 iph = ipv6_hdr(skb);
375 iph->daddr = fl6->daddr;
376
377 mtu_info = IP6CBMTU(skb);
378
379 mtu_info->ip6m_mtu = mtu;
380 mtu_info->ip6m_addr.sin6_family = AF_INET6;
381 mtu_info->ip6m_addr.sin6_port = 0;
382 mtu_info->ip6m_addr.sin6_flowinfo = 0;
383 mtu_info->ip6m_addr.sin6_scope_id = fl6->flowi6_oif;
384 mtu_info->ip6m_addr.sin6_addr = ipv6_hdr(skb)->daddr;
385
386 __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
387 skb_reset_transport_header(skb);
388
389 skb = xchg(&np->rxpmtu, skb);
390 kfree_skb(skb);
391 }
392
393 /* For some errors we have valid addr_offset even with zero payload and
394 * zero port. Also, addr_offset should be supported if port is set.
395 */
ipv6_datagram_support_addr(struct sock_exterr_skb * serr)396 static inline bool ipv6_datagram_support_addr(struct sock_exterr_skb *serr)
397 {
398 return serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6 ||
399 serr->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
400 serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL || serr->port;
401 }
402
403 /* IPv6 supports cmsg on all origins aside from SO_EE_ORIGIN_LOCAL.
404 *
405 * At one point, excluding local errors was a quick test to identify icmp/icmp6
406 * errors. This is no longer true, but the test remained, so the v6 stack,
407 * unlike v4, also honors cmsg requests on all wifi and timestamp errors.
408 */
ip6_datagram_support_cmsg(struct sk_buff * skb,struct sock_exterr_skb * serr)409 static bool ip6_datagram_support_cmsg(struct sk_buff *skb,
410 struct sock_exterr_skb *serr)
411 {
412 if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
413 serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6)
414 return true;
415
416 if (serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL)
417 return false;
418
419 if (!IP6CB(skb)->iif)
420 return false;
421
422 return true;
423 }
424
425 /*
426 * Handle MSG_ERRQUEUE
427 */
ipv6_recv_error(struct sock * sk,struct msghdr * msg,int len,int * addr_len)428 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
429 {
430 struct ipv6_pinfo *np = inet6_sk(sk);
431 struct sock_exterr_skb *serr;
432 struct sk_buff *skb;
433 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name);
434 struct {
435 struct sock_extended_err ee;
436 struct sockaddr_in6 offender;
437 } errhdr;
438 int err;
439 int copied;
440
441 err = -EAGAIN;
442 skb = sock_dequeue_err_skb(sk);
443 if (!skb)
444 goto out;
445
446 copied = skb->len;
447 if (copied > len) {
448 msg->msg_flags |= MSG_TRUNC;
449 copied = len;
450 }
451 err = skb_copy_datagram_msg(skb, 0, msg, copied);
452 if (unlikely(err)) {
453 kfree_skb(skb);
454 return err;
455 }
456 sock_recv_timestamp(msg, sk, skb);
457
458 serr = SKB_EXT_ERR(skb);
459
460 if (sin && ipv6_datagram_support_addr(serr)) {
461 const unsigned char *nh = skb_network_header(skb);
462 sin->sin6_family = AF_INET6;
463 sin->sin6_flowinfo = 0;
464 sin->sin6_port = serr->port;
465 if (skb->protocol == htons(ETH_P_IPV6)) {
466 const struct ipv6hdr *ip6h = container_of((struct in6_addr *)(nh + serr->addr_offset),
467 struct ipv6hdr, daddr);
468 sin->sin6_addr = ip6h->daddr;
469 if (np->sndflow)
470 sin->sin6_flowinfo = ip6_flowinfo(ip6h);
471 sin->sin6_scope_id =
472 ipv6_iface_scope_id(&sin->sin6_addr,
473 IP6CB(skb)->iif);
474 } else {
475 ipv6_addr_set_v4mapped(*(__be32 *)(nh + serr->addr_offset),
476 &sin->sin6_addr);
477 sin->sin6_scope_id = 0;
478 }
479 *addr_len = sizeof(*sin);
480 }
481
482 memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
483 sin = &errhdr.offender;
484 memset(sin, 0, sizeof(*sin));
485
486 if (ip6_datagram_support_cmsg(skb, serr)) {
487 sin->sin6_family = AF_INET6;
488 if (np->rxopt.all)
489 ip6_datagram_recv_common_ctl(sk, msg, skb);
490 if (skb->protocol == htons(ETH_P_IPV6)) {
491 sin->sin6_addr = ipv6_hdr(skb)->saddr;
492 if (np->rxopt.all)
493 ip6_datagram_recv_specific_ctl(sk, msg, skb);
494 sin->sin6_scope_id =
495 ipv6_iface_scope_id(&sin->sin6_addr,
496 IP6CB(skb)->iif);
497 } else {
498 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
499 &sin->sin6_addr);
500 if (inet_sk(sk)->cmsg_flags)
501 ip_cmsg_recv(msg, skb);
502 }
503 }
504
505 put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr);
506
507 /* Now we could try to dump offended packet options */
508
509 msg->msg_flags |= MSG_ERRQUEUE;
510 err = copied;
511
512 consume_skb(skb);
513 out:
514 return err;
515 }
516 EXPORT_SYMBOL_GPL(ipv6_recv_error);
517
518 /*
519 * Handle IPV6_RECVPATHMTU
520 */
ipv6_recv_rxpmtu(struct sock * sk,struct msghdr * msg,int len,int * addr_len)521 int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len,
522 int *addr_len)
523 {
524 struct ipv6_pinfo *np = inet6_sk(sk);
525 struct sk_buff *skb;
526 struct ip6_mtuinfo mtu_info;
527 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name);
528 int err;
529 int copied;
530
531 err = -EAGAIN;
532 skb = xchg(&np->rxpmtu, NULL);
533 if (!skb)
534 goto out;
535
536 copied = skb->len;
537 if (copied > len) {
538 msg->msg_flags |= MSG_TRUNC;
539 copied = len;
540 }
541 err = skb_copy_datagram_msg(skb, 0, msg, copied);
542 if (err)
543 goto out_free_skb;
544
545 sock_recv_timestamp(msg, sk, skb);
546
547 memcpy(&mtu_info, IP6CBMTU(skb), sizeof(mtu_info));
548
549 if (sin) {
550 sin->sin6_family = AF_INET6;
551 sin->sin6_flowinfo = 0;
552 sin->sin6_port = 0;
553 sin->sin6_scope_id = mtu_info.ip6m_addr.sin6_scope_id;
554 sin->sin6_addr = mtu_info.ip6m_addr.sin6_addr;
555 *addr_len = sizeof(*sin);
556 }
557
558 put_cmsg(msg, SOL_IPV6, IPV6_PATHMTU, sizeof(mtu_info), &mtu_info);
559
560 err = copied;
561
562 out_free_skb:
563 kfree_skb(skb);
564 out:
565 return err;
566 }
567
568
ip6_datagram_recv_common_ctl(struct sock * sk,struct msghdr * msg,struct sk_buff * skb)569 void ip6_datagram_recv_common_ctl(struct sock *sk, struct msghdr *msg,
570 struct sk_buff *skb)
571 {
572 struct ipv6_pinfo *np = inet6_sk(sk);
573 bool is_ipv6 = skb->protocol == htons(ETH_P_IPV6);
574
575 if (np->rxopt.bits.rxinfo) {
576 struct in6_pktinfo src_info;
577
578 if (is_ipv6) {
579 src_info.ipi6_ifindex = IP6CB(skb)->iif;
580 src_info.ipi6_addr = ipv6_hdr(skb)->daddr;
581 } else {
582 src_info.ipi6_ifindex =
583 PKTINFO_SKB_CB(skb)->ipi_ifindex;
584 ipv6_addr_set_v4mapped(ip_hdr(skb)->daddr,
585 &src_info.ipi6_addr);
586 }
587
588 if (src_info.ipi6_ifindex >= 0)
589 put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO,
590 sizeof(src_info), &src_info);
591 }
592 }
593
ip6_datagram_recv_specific_ctl(struct sock * sk,struct msghdr * msg,struct sk_buff * skb)594 void ip6_datagram_recv_specific_ctl(struct sock *sk, struct msghdr *msg,
595 struct sk_buff *skb)
596 {
597 struct ipv6_pinfo *np = inet6_sk(sk);
598 struct inet6_skb_parm *opt = IP6CB(skb);
599 unsigned char *nh = skb_network_header(skb);
600
601 if (np->rxopt.bits.rxhlim) {
602 int hlim = ipv6_hdr(skb)->hop_limit;
603 put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
604 }
605
606 if (np->rxopt.bits.rxtclass) {
607 int tclass = ipv6_get_dsfield(ipv6_hdr(skb));
608 put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
609 }
610
611 if (np->rxopt.bits.rxflow) {
612 __be32 flowinfo = ip6_flowinfo((struct ipv6hdr *)nh);
613 if (flowinfo)
614 put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
615 }
616
617 /* HbH is allowed only once */
618 if (np->rxopt.bits.hopopts && (opt->flags & IP6SKB_HOPBYHOP)) {
619 u8 *ptr = nh + sizeof(struct ipv6hdr);
620 put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr);
621 }
622
623 if (opt->lastopt &&
624 (np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) {
625 /*
626 * Silly enough, but we need to reparse in order to
627 * report extension headers (except for HbH)
628 * in order.
629 *
630 * Also note that IPV6_RECVRTHDRDSTOPTS is NOT
631 * (and WILL NOT be) defined because
632 * IPV6_RECVDSTOPTS is more generic. --yoshfuji
633 */
634 unsigned int off = sizeof(struct ipv6hdr);
635 u8 nexthdr = ipv6_hdr(skb)->nexthdr;
636
637 while (off <= opt->lastopt) {
638 unsigned int len;
639 u8 *ptr = nh + off;
640
641 switch (nexthdr) {
642 case IPPROTO_DSTOPTS:
643 nexthdr = ptr[0];
644 len = (ptr[1] + 1) << 3;
645 if (np->rxopt.bits.dstopts)
646 put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, ptr);
647 break;
648 case IPPROTO_ROUTING:
649 nexthdr = ptr[0];
650 len = (ptr[1] + 1) << 3;
651 if (np->rxopt.bits.srcrt)
652 put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, ptr);
653 break;
654 case IPPROTO_AH:
655 nexthdr = ptr[0];
656 len = (ptr[1] + 2) << 2;
657 break;
658 default:
659 nexthdr = ptr[0];
660 len = (ptr[1] + 1) << 3;
661 break;
662 }
663
664 off += len;
665 }
666 }
667
668 /* socket options in old style */
669 if (np->rxopt.bits.rxoinfo) {
670 struct in6_pktinfo src_info;
671
672 src_info.ipi6_ifindex = opt->iif;
673 src_info.ipi6_addr = ipv6_hdr(skb)->daddr;
674 put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
675 }
676 if (np->rxopt.bits.rxohlim) {
677 int hlim = ipv6_hdr(skb)->hop_limit;
678 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
679 }
680 if (np->rxopt.bits.ohopopts && (opt->flags & IP6SKB_HOPBYHOP)) {
681 u8 *ptr = nh + sizeof(struct ipv6hdr);
682 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, (ptr[1]+1)<<3, ptr);
683 }
684 if (np->rxopt.bits.odstopts && opt->dst0) {
685 u8 *ptr = nh + opt->dst0;
686 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
687 }
688 if (np->rxopt.bits.osrcrt && opt->srcrt) {
689 struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt);
690 put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, (rthdr->hdrlen+1) << 3, rthdr);
691 }
692 if (np->rxopt.bits.odstopts && opt->dst1) {
693 u8 *ptr = nh + opt->dst1;
694 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
695 }
696 if (np->rxopt.bits.rxorigdstaddr) {
697 struct sockaddr_in6 sin6;
698 __be16 *ports = (__be16 *) skb_transport_header(skb);
699
700 if (skb_transport_offset(skb) + 4 <= (int)skb->len) {
701 /* All current transport protocols have the port numbers in the
702 * first four bytes of the transport header and this function is
703 * written with this assumption in mind.
704 */
705
706 sin6.sin6_family = AF_INET6;
707 sin6.sin6_addr = ipv6_hdr(skb)->daddr;
708 sin6.sin6_port = ports[1];
709 sin6.sin6_flowinfo = 0;
710 sin6.sin6_scope_id =
711 ipv6_iface_scope_id(&ipv6_hdr(skb)->daddr,
712 opt->iif);
713
714 put_cmsg(msg, SOL_IPV6, IPV6_ORIGDSTADDR, sizeof(sin6), &sin6);
715 }
716 }
717 }
718
ip6_datagram_recv_ctl(struct sock * sk,struct msghdr * msg,struct sk_buff * skb)719 void ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg,
720 struct sk_buff *skb)
721 {
722 ip6_datagram_recv_common_ctl(sk, msg, skb);
723 ip6_datagram_recv_specific_ctl(sk, msg, skb);
724 }
725 EXPORT_SYMBOL_GPL(ip6_datagram_recv_ctl);
726
ip6_datagram_send_ctl(struct net * net,struct sock * sk,struct msghdr * msg,struct flowi6 * fl6,struct ipcm6_cookie * ipc6,struct sockcm_cookie * sockc)727 int ip6_datagram_send_ctl(struct net *net, struct sock *sk,
728 struct msghdr *msg, struct flowi6 *fl6,
729 struct ipcm6_cookie *ipc6, struct sockcm_cookie *sockc)
730 {
731 struct in6_pktinfo *src_info;
732 struct cmsghdr *cmsg;
733 struct ipv6_rt_hdr *rthdr;
734 struct ipv6_opt_hdr *hdr;
735 struct ipv6_txoptions *opt = ipc6->opt;
736 int len;
737 int err = 0;
738
739 for_each_cmsghdr(cmsg, msg) {
740 int addr_type;
741
742 if (!CMSG_OK(msg, cmsg)) {
743 err = -EINVAL;
744 goto exit_f;
745 }
746
747 if (cmsg->cmsg_level == SOL_SOCKET) {
748 err = __sock_cmsg_send(sk, msg, cmsg, sockc);
749 if (err)
750 return err;
751 continue;
752 }
753
754 if (cmsg->cmsg_level != SOL_IPV6)
755 continue;
756
757 switch (cmsg->cmsg_type) {
758 case IPV6_PKTINFO:
759 case IPV6_2292PKTINFO:
760 {
761 struct net_device *dev = NULL;
762
763 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) {
764 err = -EINVAL;
765 goto exit_f;
766 }
767
768 src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
769
770 if (src_info->ipi6_ifindex) {
771 if (fl6->flowi6_oif &&
772 src_info->ipi6_ifindex != fl6->flowi6_oif)
773 return -EINVAL;
774 fl6->flowi6_oif = src_info->ipi6_ifindex;
775 }
776
777 addr_type = __ipv6_addr_type(&src_info->ipi6_addr);
778
779 rcu_read_lock();
780 if (fl6->flowi6_oif) {
781 dev = dev_get_by_index_rcu(net, fl6->flowi6_oif);
782 if (!dev) {
783 rcu_read_unlock();
784 return -ENODEV;
785 }
786 } else if (addr_type & IPV6_ADDR_LINKLOCAL) {
787 rcu_read_unlock();
788 return -EINVAL;
789 }
790
791 if (addr_type != IPV6_ADDR_ANY) {
792 int strict = __ipv6_addr_src_scope(addr_type) <= IPV6_ADDR_SCOPE_LINKLOCAL;
793 if (!(inet_sk(sk)->freebind || inet_sk(sk)->transparent) &&
794 !ipv6_chk_addr(net, &src_info->ipi6_addr,
795 strict ? dev : NULL, 0) &&
796 !ipv6_chk_acast_addr_src(net, dev,
797 &src_info->ipi6_addr))
798 err = -EINVAL;
799 else
800 fl6->saddr = src_info->ipi6_addr;
801 }
802
803 rcu_read_unlock();
804
805 if (err)
806 goto exit_f;
807
808 break;
809 }
810
811 case IPV6_FLOWINFO:
812 if (cmsg->cmsg_len < CMSG_LEN(4)) {
813 err = -EINVAL;
814 goto exit_f;
815 }
816
817 if (fl6->flowlabel&IPV6_FLOWINFO_MASK) {
818 if ((fl6->flowlabel^*(__be32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) {
819 err = -EINVAL;
820 goto exit_f;
821 }
822 }
823 fl6->flowlabel = IPV6_FLOWINFO_MASK & *(__be32 *)CMSG_DATA(cmsg);
824 break;
825
826 case IPV6_2292HOPOPTS:
827 case IPV6_HOPOPTS:
828 if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
829 err = -EINVAL;
830 goto exit_f;
831 }
832
833 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
834 len = ((hdr->hdrlen + 1) << 3);
835 if (cmsg->cmsg_len < CMSG_LEN(len)) {
836 err = -EINVAL;
837 goto exit_f;
838 }
839 if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
840 err = -EPERM;
841 goto exit_f;
842 }
843 opt->opt_nflen += len;
844 opt->hopopt = hdr;
845 break;
846
847 case IPV6_2292DSTOPTS:
848 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
849 err = -EINVAL;
850 goto exit_f;
851 }
852
853 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
854 len = ((hdr->hdrlen + 1) << 3);
855 if (cmsg->cmsg_len < CMSG_LEN(len)) {
856 err = -EINVAL;
857 goto exit_f;
858 }
859 if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
860 err = -EPERM;
861 goto exit_f;
862 }
863 if (opt->dst1opt) {
864 err = -EINVAL;
865 goto exit_f;
866 }
867 opt->opt_flen += len;
868 opt->dst1opt = hdr;
869 break;
870
871 case IPV6_DSTOPTS:
872 case IPV6_RTHDRDSTOPTS:
873 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
874 err = -EINVAL;
875 goto exit_f;
876 }
877
878 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
879 len = ((hdr->hdrlen + 1) << 3);
880 if (cmsg->cmsg_len < CMSG_LEN(len)) {
881 err = -EINVAL;
882 goto exit_f;
883 }
884 if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
885 err = -EPERM;
886 goto exit_f;
887 }
888 if (cmsg->cmsg_type == IPV6_DSTOPTS) {
889 opt->opt_flen += len;
890 opt->dst1opt = hdr;
891 } else {
892 opt->opt_nflen += len;
893 opt->dst0opt = hdr;
894 }
895 break;
896
897 case IPV6_2292RTHDR:
898 case IPV6_RTHDR:
899 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) {
900 err = -EINVAL;
901 goto exit_f;
902 }
903
904 rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg);
905
906 switch (rthdr->type) {
907 #if IS_ENABLED(CONFIG_IPV6_MIP6)
908 case IPV6_SRCRT_TYPE_2:
909 if (rthdr->hdrlen != 2 ||
910 rthdr->segments_left != 1) {
911 err = -EINVAL;
912 goto exit_f;
913 }
914 break;
915 #endif
916 default:
917 err = -EINVAL;
918 goto exit_f;
919 }
920
921 len = ((rthdr->hdrlen + 1) << 3);
922
923 if (cmsg->cmsg_len < CMSG_LEN(len)) {
924 err = -EINVAL;
925 goto exit_f;
926 }
927
928 /* segments left must also match */
929 if ((rthdr->hdrlen >> 1) != rthdr->segments_left) {
930 err = -EINVAL;
931 goto exit_f;
932 }
933
934 opt->opt_nflen += len;
935 opt->srcrt = rthdr;
936
937 if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) {
938 int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3);
939
940 opt->opt_nflen += dsthdrlen;
941 opt->dst0opt = opt->dst1opt;
942 opt->dst1opt = NULL;
943 opt->opt_flen -= dsthdrlen;
944 }
945
946 break;
947
948 case IPV6_2292HOPLIMIT:
949 case IPV6_HOPLIMIT:
950 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
951 err = -EINVAL;
952 goto exit_f;
953 }
954
955 ipc6->hlimit = *(int *)CMSG_DATA(cmsg);
956 if (ipc6->hlimit < -1 || ipc6->hlimit > 0xff) {
957 err = -EINVAL;
958 goto exit_f;
959 }
960
961 break;
962
963 case IPV6_TCLASS:
964 {
965 int tc;
966
967 err = -EINVAL;
968 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
969 goto exit_f;
970
971 tc = *(int *)CMSG_DATA(cmsg);
972 if (tc < -1 || tc > 0xff)
973 goto exit_f;
974
975 err = 0;
976 ipc6->tclass = tc;
977
978 break;
979 }
980
981 case IPV6_DONTFRAG:
982 {
983 int df;
984
985 err = -EINVAL;
986 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
987 goto exit_f;
988
989 df = *(int *)CMSG_DATA(cmsg);
990 if (df < 0 || df > 1)
991 goto exit_f;
992
993 err = 0;
994 ipc6->dontfrag = df;
995
996 break;
997 }
998 default:
999 net_dbg_ratelimited("invalid cmsg type: %d\n",
1000 cmsg->cmsg_type);
1001 err = -EINVAL;
1002 goto exit_f;
1003 }
1004 }
1005
1006 exit_f:
1007 return err;
1008 }
1009 EXPORT_SYMBOL_GPL(ip6_datagram_send_ctl);
1010
ip6_dgram_sock_seq_show(struct seq_file * seq,struct sock * sp,__u16 srcp,__u16 destp,int bucket)1011 void ip6_dgram_sock_seq_show(struct seq_file *seq, struct sock *sp,
1012 __u16 srcp, __u16 destp, int bucket)
1013 {
1014 const struct in6_addr *dest, *src;
1015
1016 dest = &sp->sk_v6_daddr;
1017 src = &sp->sk_v6_rcv_saddr;
1018 seq_printf(seq,
1019 "%5d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1020 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %d\n",
1021 bucket,
1022 src->s6_addr32[0], src->s6_addr32[1],
1023 src->s6_addr32[2], src->s6_addr32[3], srcp,
1024 dest->s6_addr32[0], dest->s6_addr32[1],
1025 dest->s6_addr32[2], dest->s6_addr32[3], destp,
1026 sp->sk_state,
1027 sk_wmem_alloc_get(sp),
1028 sk_rmem_alloc_get(sp),
1029 0, 0L, 0,
1030 from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)),
1031 0,
1032 sock_i_ino(sp),
1033 atomic_read(&sp->sk_refcnt), sp,
1034 atomic_read(&sp->sk_drops));
1035 }
1036