1 /*
2 * common UDP/RAW code
3 * Linux INET6 implementation
4 *
5 * Authors:
6 * Pedro Roque <roque@di.fc.ul.pt>
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * as published by the Free Software Foundation; either version
11 * 2 of the License, or (at your option) any later version.
12 */
13
14 #include <linux/capability.h>
15 #include <linux/errno.h>
16 #include <linux/types.h>
17 #include <linux/kernel.h>
18 #include <linux/interrupt.h>
19 #include <linux/socket.h>
20 #include <linux/sockios.h>
21 #include <linux/in6.h>
22 #include <linux/ipv6.h>
23 #include <linux/route.h>
24 #include <linux/slab.h>
25 #include <linux/export.h>
26
27 #include <net/ipv6.h>
28 #include <net/ndisc.h>
29 #include <net/addrconf.h>
30 #include <net/transp_v6.h>
31 #include <net/ip6_route.h>
32 #include <net/tcp_states.h>
33 #include <net/dsfield.h>
34
35 #include <linux/errqueue.h>
36 #include <linux/uaccess.h>
37
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, old_daddr;
150 __be32 fl6_flowlabel = 0;
151 __be32 old_fl6_flowlabel;
152 __be16 old_dport;
153 int addr_type;
154 int err;
155
156 if (usin->sin6_family == AF_INET) {
157 if (__ipv6_only_sock(sk))
158 return -EAFNOSUPPORT;
159 err = __ip4_datagram_connect(sk, uaddr, addr_len);
160 goto ipv4_connected;
161 }
162
163 if (addr_len < SIN6_LEN_RFC2133)
164 return -EINVAL;
165
166 if (usin->sin6_family != AF_INET6)
167 return -EAFNOSUPPORT;
168
169 if (np->sndflow)
170 fl6_flowlabel = usin->sin6_flowinfo & IPV6_FLOWINFO_MASK;
171
172 if (ipv6_addr_any(&usin->sin6_addr)) {
173 /*
174 * connect to self
175 */
176 if (ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr))
177 ipv6_addr_set_v4mapped(htonl(INADDR_LOOPBACK),
178 &usin->sin6_addr);
179 else
180 usin->sin6_addr = in6addr_loopback;
181 }
182
183 addr_type = ipv6_addr_type(&usin->sin6_addr);
184
185 daddr = &usin->sin6_addr;
186
187 if (addr_type & IPV6_ADDR_MAPPED) {
188 struct sockaddr_in sin;
189
190 if (__ipv6_only_sock(sk)) {
191 err = -ENETUNREACH;
192 goto out;
193 }
194 sin.sin_family = AF_INET;
195 sin.sin_addr.s_addr = daddr->s6_addr32[3];
196 sin.sin_port = usin->sin6_port;
197
198 err = __ip4_datagram_connect(sk,
199 (struct sockaddr *) &sin,
200 sizeof(sin));
201
202 ipv4_connected:
203 if (err)
204 goto out;
205
206 ipv6_addr_set_v4mapped(inet->inet_daddr, &sk->sk_v6_daddr);
207
208 if (ipv6_addr_any(&np->saddr) ||
209 ipv6_mapped_addr_any(&np->saddr))
210 ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr);
211
212 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr) ||
213 ipv6_mapped_addr_any(&sk->sk_v6_rcv_saddr)) {
214 ipv6_addr_set_v4mapped(inet->inet_rcv_saddr,
215 &sk->sk_v6_rcv_saddr);
216 if (sk->sk_prot->rehash)
217 sk->sk_prot->rehash(sk);
218 }
219
220 goto out;
221 }
222
223 if (__ipv6_addr_needs_scope_id(addr_type)) {
224 if (addr_len >= sizeof(struct sockaddr_in6) &&
225 usin->sin6_scope_id) {
226 if (sk->sk_bound_dev_if &&
227 sk->sk_bound_dev_if != usin->sin6_scope_id) {
228 err = -EINVAL;
229 goto out;
230 }
231 sk->sk_bound_dev_if = usin->sin6_scope_id;
232 }
233
234 if (!sk->sk_bound_dev_if && (addr_type & IPV6_ADDR_MULTICAST))
235 sk->sk_bound_dev_if = np->mcast_oif;
236
237 /* Connect to link-local address requires an interface */
238 if (!sk->sk_bound_dev_if) {
239 err = -EINVAL;
240 goto out;
241 }
242 }
243
244 /* save the current peer information before updating it */
245 old_daddr = sk->sk_v6_daddr;
246 old_fl6_flowlabel = np->flow_label;
247 old_dport = inet->inet_dport;
248
249 sk->sk_v6_daddr = *daddr;
250 np->flow_label = fl6_flowlabel;
251 inet->inet_dport = usin->sin6_port;
252
253 /*
254 * Check for a route to destination an obtain the
255 * destination cache for it.
256 */
257
258 err = ip6_datagram_dst_update(sk, true);
259 if (err) {
260 /* Restore the socket peer info, to keep it consistent with
261 * the old socket state
262 */
263 sk->sk_v6_daddr = old_daddr;
264 np->flow_label = old_fl6_flowlabel;
265 inet->inet_dport = old_dport;
266 goto out;
267 }
268
269 sk->sk_state = TCP_ESTABLISHED;
270 sk_set_txhash(sk);
271 out:
272 return err;
273 }
274 EXPORT_SYMBOL_GPL(__ip6_datagram_connect);
275
ip6_datagram_connect(struct sock * sk,struct sockaddr * uaddr,int addr_len)276 int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
277 {
278 int res;
279
280 lock_sock(sk);
281 res = __ip6_datagram_connect(sk, uaddr, addr_len);
282 release_sock(sk);
283 return res;
284 }
285 EXPORT_SYMBOL_GPL(ip6_datagram_connect);
286
ip6_datagram_connect_v6_only(struct sock * sk,struct sockaddr * uaddr,int addr_len)287 int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *uaddr,
288 int addr_len)
289 {
290 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, uaddr);
291 if (sin6->sin6_family != AF_INET6)
292 return -EAFNOSUPPORT;
293 return ip6_datagram_connect(sk, uaddr, addr_len);
294 }
295 EXPORT_SYMBOL_GPL(ip6_datagram_connect_v6_only);
296
ipv6_icmp_error(struct sock * sk,struct sk_buff * skb,int err,__be16 port,u32 info,u8 * payload)297 void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
298 __be16 port, u32 info, u8 *payload)
299 {
300 struct ipv6_pinfo *np = inet6_sk(sk);
301 struct icmp6hdr *icmph = icmp6_hdr(skb);
302 struct sock_exterr_skb *serr;
303
304 if (!np->recverr)
305 return;
306
307 skb = skb_clone(skb, GFP_ATOMIC);
308 if (!skb)
309 return;
310
311 skb->protocol = htons(ETH_P_IPV6);
312
313 serr = SKB_EXT_ERR(skb);
314 serr->ee.ee_errno = err;
315 serr->ee.ee_origin = SO_EE_ORIGIN_ICMP6;
316 serr->ee.ee_type = icmph->icmp6_type;
317 serr->ee.ee_code = icmph->icmp6_code;
318 serr->ee.ee_pad = 0;
319 serr->ee.ee_info = info;
320 serr->ee.ee_data = 0;
321 serr->addr_offset = (u8 *)&(((struct ipv6hdr *)(icmph + 1))->daddr) -
322 skb_network_header(skb);
323 serr->port = port;
324
325 __skb_pull(skb, payload - skb->data);
326 skb_reset_transport_header(skb);
327
328 if (sock_queue_err_skb(sk, skb))
329 kfree_skb(skb);
330 }
331
ipv6_local_error(struct sock * sk,int err,struct flowi6 * fl6,u32 info)332 void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info)
333 {
334 const struct ipv6_pinfo *np = inet6_sk(sk);
335 struct sock_exterr_skb *serr;
336 struct ipv6hdr *iph;
337 struct sk_buff *skb;
338
339 if (!np->recverr)
340 return;
341
342 skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
343 if (!skb)
344 return;
345
346 skb->protocol = htons(ETH_P_IPV6);
347
348 skb_put(skb, sizeof(struct ipv6hdr));
349 skb_reset_network_header(skb);
350 iph = ipv6_hdr(skb);
351 iph->daddr = fl6->daddr;
352 ip6_flow_hdr(iph, 0, 0);
353
354 serr = SKB_EXT_ERR(skb);
355 serr->ee.ee_errno = err;
356 serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
357 serr->ee.ee_type = 0;
358 serr->ee.ee_code = 0;
359 serr->ee.ee_pad = 0;
360 serr->ee.ee_info = info;
361 serr->ee.ee_data = 0;
362 serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
363 serr->port = fl6->fl6_dport;
364
365 __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
366 skb_reset_transport_header(skb);
367
368 if (sock_queue_err_skb(sk, skb))
369 kfree_skb(skb);
370 }
371
ipv6_local_rxpmtu(struct sock * sk,struct flowi6 * fl6,u32 mtu)372 void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu)
373 {
374 struct ipv6_pinfo *np = inet6_sk(sk);
375 struct ipv6hdr *iph;
376 struct sk_buff *skb;
377 struct ip6_mtuinfo *mtu_info;
378
379 if (!np->rxopt.bits.rxpmtu)
380 return;
381
382 skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
383 if (!skb)
384 return;
385
386 skb_put(skb, sizeof(struct ipv6hdr));
387 skb_reset_network_header(skb);
388 iph = ipv6_hdr(skb);
389 iph->daddr = fl6->daddr;
390
391 mtu_info = IP6CBMTU(skb);
392
393 mtu_info->ip6m_mtu = mtu;
394 mtu_info->ip6m_addr.sin6_family = AF_INET6;
395 mtu_info->ip6m_addr.sin6_port = 0;
396 mtu_info->ip6m_addr.sin6_flowinfo = 0;
397 mtu_info->ip6m_addr.sin6_scope_id = fl6->flowi6_oif;
398 mtu_info->ip6m_addr.sin6_addr = ipv6_hdr(skb)->daddr;
399
400 __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
401 skb_reset_transport_header(skb);
402
403 skb = xchg(&np->rxpmtu, skb);
404 kfree_skb(skb);
405 }
406
407 /* For some errors we have valid addr_offset even with zero payload and
408 * zero port. Also, addr_offset should be supported if port is set.
409 */
ipv6_datagram_support_addr(struct sock_exterr_skb * serr)410 static inline bool ipv6_datagram_support_addr(struct sock_exterr_skb *serr)
411 {
412 return serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6 ||
413 serr->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
414 serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL || serr->port;
415 }
416
417 /* IPv6 supports cmsg on all origins aside from SO_EE_ORIGIN_LOCAL.
418 *
419 * At one point, excluding local errors was a quick test to identify icmp/icmp6
420 * errors. This is no longer true, but the test remained, so the v6 stack,
421 * unlike v4, also honors cmsg requests on all wifi and timestamp errors.
422 */
ip6_datagram_support_cmsg(struct sk_buff * skb,struct sock_exterr_skb * serr)423 static bool ip6_datagram_support_cmsg(struct sk_buff *skb,
424 struct sock_exterr_skb *serr)
425 {
426 if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
427 serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6)
428 return true;
429
430 if (serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL)
431 return false;
432
433 if (!IP6CB(skb)->iif)
434 return false;
435
436 return true;
437 }
438
439 /*
440 * Handle MSG_ERRQUEUE
441 */
ipv6_recv_error(struct sock * sk,struct msghdr * msg,int len,int * addr_len)442 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
443 {
444 struct ipv6_pinfo *np = inet6_sk(sk);
445 struct sock_exterr_skb *serr;
446 struct sk_buff *skb;
447 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name);
448 struct {
449 struct sock_extended_err ee;
450 struct sockaddr_in6 offender;
451 } errhdr;
452 int err;
453 int copied;
454
455 err = -EAGAIN;
456 skb = sock_dequeue_err_skb(sk);
457 if (!skb)
458 goto out;
459
460 copied = skb->len;
461 if (copied > len) {
462 msg->msg_flags |= MSG_TRUNC;
463 copied = len;
464 }
465 err = skb_copy_datagram_msg(skb, 0, msg, copied);
466 if (unlikely(err)) {
467 kfree_skb(skb);
468 return err;
469 }
470 sock_recv_timestamp(msg, sk, skb);
471
472 serr = SKB_EXT_ERR(skb);
473
474 if (sin && ipv6_datagram_support_addr(serr)) {
475 const unsigned char *nh = skb_network_header(skb);
476 sin->sin6_family = AF_INET6;
477 sin->sin6_flowinfo = 0;
478 sin->sin6_port = serr->port;
479 if (skb->protocol == htons(ETH_P_IPV6)) {
480 const struct ipv6hdr *ip6h = container_of((struct in6_addr *)(nh + serr->addr_offset),
481 struct ipv6hdr, daddr);
482 sin->sin6_addr = ip6h->daddr;
483 if (np->sndflow)
484 sin->sin6_flowinfo = ip6_flowinfo(ip6h);
485 sin->sin6_scope_id =
486 ipv6_iface_scope_id(&sin->sin6_addr,
487 IP6CB(skb)->iif);
488 } else {
489 ipv6_addr_set_v4mapped(*(__be32 *)(nh + serr->addr_offset),
490 &sin->sin6_addr);
491 sin->sin6_scope_id = 0;
492 }
493 *addr_len = sizeof(*sin);
494 }
495
496 memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
497 sin = &errhdr.offender;
498 memset(sin, 0, sizeof(*sin));
499
500 if (ip6_datagram_support_cmsg(skb, serr)) {
501 sin->sin6_family = AF_INET6;
502 if (np->rxopt.all)
503 ip6_datagram_recv_common_ctl(sk, msg, skb);
504 if (skb->protocol == htons(ETH_P_IPV6)) {
505 sin->sin6_addr = ipv6_hdr(skb)->saddr;
506 if (np->rxopt.all)
507 ip6_datagram_recv_specific_ctl(sk, msg, skb);
508 sin->sin6_scope_id =
509 ipv6_iface_scope_id(&sin->sin6_addr,
510 IP6CB(skb)->iif);
511 } else {
512 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
513 &sin->sin6_addr);
514 if (inet_sk(sk)->cmsg_flags)
515 ip_cmsg_recv(msg, skb);
516 }
517 }
518
519 put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr);
520
521 /* Now we could try to dump offended packet options */
522
523 msg->msg_flags |= MSG_ERRQUEUE;
524 err = copied;
525
526 consume_skb(skb);
527 out:
528 return err;
529 }
530 EXPORT_SYMBOL_GPL(ipv6_recv_error);
531
532 /*
533 * Handle IPV6_RECVPATHMTU
534 */
ipv6_recv_rxpmtu(struct sock * sk,struct msghdr * msg,int len,int * addr_len)535 int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len,
536 int *addr_len)
537 {
538 struct ipv6_pinfo *np = inet6_sk(sk);
539 struct sk_buff *skb;
540 struct ip6_mtuinfo mtu_info;
541 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name);
542 int err;
543 int copied;
544
545 err = -EAGAIN;
546 skb = xchg(&np->rxpmtu, NULL);
547 if (!skb)
548 goto out;
549
550 copied = skb->len;
551 if (copied > len) {
552 msg->msg_flags |= MSG_TRUNC;
553 copied = len;
554 }
555 err = skb_copy_datagram_msg(skb, 0, msg, copied);
556 if (err)
557 goto out_free_skb;
558
559 sock_recv_timestamp(msg, sk, skb);
560
561 memcpy(&mtu_info, IP6CBMTU(skb), sizeof(mtu_info));
562
563 if (sin) {
564 sin->sin6_family = AF_INET6;
565 sin->sin6_flowinfo = 0;
566 sin->sin6_port = 0;
567 sin->sin6_scope_id = mtu_info.ip6m_addr.sin6_scope_id;
568 sin->sin6_addr = mtu_info.ip6m_addr.sin6_addr;
569 *addr_len = sizeof(*sin);
570 }
571
572 put_cmsg(msg, SOL_IPV6, IPV6_PATHMTU, sizeof(mtu_info), &mtu_info);
573
574 err = copied;
575
576 out_free_skb:
577 kfree_skb(skb);
578 out:
579 return err;
580 }
581
582
ip6_datagram_recv_common_ctl(struct sock * sk,struct msghdr * msg,struct sk_buff * skb)583 void ip6_datagram_recv_common_ctl(struct sock *sk, struct msghdr *msg,
584 struct sk_buff *skb)
585 {
586 struct ipv6_pinfo *np = inet6_sk(sk);
587 bool is_ipv6 = skb->protocol == htons(ETH_P_IPV6);
588
589 if (np->rxopt.bits.rxinfo) {
590 struct in6_pktinfo src_info;
591
592 if (is_ipv6) {
593 src_info.ipi6_ifindex = IP6CB(skb)->iif;
594 src_info.ipi6_addr = ipv6_hdr(skb)->daddr;
595 } else {
596 src_info.ipi6_ifindex =
597 PKTINFO_SKB_CB(skb)->ipi_ifindex;
598 ipv6_addr_set_v4mapped(ip_hdr(skb)->daddr,
599 &src_info.ipi6_addr);
600 }
601
602 if (src_info.ipi6_ifindex >= 0)
603 put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO,
604 sizeof(src_info), &src_info);
605 }
606 }
607
ip6_datagram_recv_specific_ctl(struct sock * sk,struct msghdr * msg,struct sk_buff * skb)608 void ip6_datagram_recv_specific_ctl(struct sock *sk, struct msghdr *msg,
609 struct sk_buff *skb)
610 {
611 struct ipv6_pinfo *np = inet6_sk(sk);
612 struct inet6_skb_parm *opt = IP6CB(skb);
613 unsigned char *nh = skb_network_header(skb);
614
615 if (np->rxopt.bits.rxhlim) {
616 int hlim = ipv6_hdr(skb)->hop_limit;
617 put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
618 }
619
620 if (np->rxopt.bits.rxtclass) {
621 int tclass = ipv6_get_dsfield(ipv6_hdr(skb));
622 put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
623 }
624
625 if (np->rxopt.bits.rxflow) {
626 __be32 flowinfo = ip6_flowinfo((struct ipv6hdr *)nh);
627 if (flowinfo)
628 put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
629 }
630
631 /* HbH is allowed only once */
632 if (np->rxopt.bits.hopopts && (opt->flags & IP6SKB_HOPBYHOP)) {
633 u8 *ptr = nh + sizeof(struct ipv6hdr);
634 put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr);
635 }
636
637 if (opt->lastopt &&
638 (np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) {
639 /*
640 * Silly enough, but we need to reparse in order to
641 * report extension headers (except for HbH)
642 * in order.
643 *
644 * Also note that IPV6_RECVRTHDRDSTOPTS is NOT
645 * (and WILL NOT be) defined because
646 * IPV6_RECVDSTOPTS is more generic. --yoshfuji
647 */
648 unsigned int off = sizeof(struct ipv6hdr);
649 u8 nexthdr = ipv6_hdr(skb)->nexthdr;
650
651 while (off <= opt->lastopt) {
652 unsigned int len;
653 u8 *ptr = nh + off;
654
655 switch (nexthdr) {
656 case IPPROTO_DSTOPTS:
657 nexthdr = ptr[0];
658 len = (ptr[1] + 1) << 3;
659 if (np->rxopt.bits.dstopts)
660 put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, ptr);
661 break;
662 case IPPROTO_ROUTING:
663 nexthdr = ptr[0];
664 len = (ptr[1] + 1) << 3;
665 if (np->rxopt.bits.srcrt)
666 put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, ptr);
667 break;
668 case IPPROTO_AH:
669 nexthdr = ptr[0];
670 len = (ptr[1] + 2) << 2;
671 break;
672 default:
673 nexthdr = ptr[0];
674 len = (ptr[1] + 1) << 3;
675 break;
676 }
677
678 off += len;
679 }
680 }
681
682 /* socket options in old style */
683 if (np->rxopt.bits.rxoinfo) {
684 struct in6_pktinfo src_info;
685
686 src_info.ipi6_ifindex = opt->iif;
687 src_info.ipi6_addr = ipv6_hdr(skb)->daddr;
688 put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
689 }
690 if (np->rxopt.bits.rxohlim) {
691 int hlim = ipv6_hdr(skb)->hop_limit;
692 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
693 }
694 if (np->rxopt.bits.ohopopts && (opt->flags & IP6SKB_HOPBYHOP)) {
695 u8 *ptr = nh + sizeof(struct ipv6hdr);
696 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, (ptr[1]+1)<<3, ptr);
697 }
698 if (np->rxopt.bits.odstopts && opt->dst0) {
699 u8 *ptr = nh + opt->dst0;
700 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
701 }
702 if (np->rxopt.bits.osrcrt && opt->srcrt) {
703 struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt);
704 put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, (rthdr->hdrlen+1) << 3, rthdr);
705 }
706 if (np->rxopt.bits.odstopts && opt->dst1) {
707 u8 *ptr = nh + opt->dst1;
708 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
709 }
710 if (np->rxopt.bits.rxorigdstaddr) {
711 struct sockaddr_in6 sin6;
712 __be16 _ports[2], *ports;
713
714 ports = skb_header_pointer(skb, skb_transport_offset(skb),
715 sizeof(_ports), &_ports);
716 if (ports) {
717 /* All current transport protocols have the port numbers in the
718 * first four bytes of the transport header and this function is
719 * written with this assumption in mind.
720 */
721 sin6.sin6_family = AF_INET6;
722 sin6.sin6_addr = ipv6_hdr(skb)->daddr;
723 sin6.sin6_port = ports[1];
724 sin6.sin6_flowinfo = 0;
725 sin6.sin6_scope_id =
726 ipv6_iface_scope_id(&ipv6_hdr(skb)->daddr,
727 opt->iif);
728
729 put_cmsg(msg, SOL_IPV6, IPV6_ORIGDSTADDR, sizeof(sin6), &sin6);
730 }
731 }
732 if (np->rxopt.bits.recvfragsize && opt->frag_max_size) {
733 int val = opt->frag_max_size;
734
735 put_cmsg(msg, SOL_IPV6, IPV6_RECVFRAGSIZE, sizeof(val), &val);
736 }
737 }
738
ip6_datagram_recv_ctl(struct sock * sk,struct msghdr * msg,struct sk_buff * skb)739 void ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg,
740 struct sk_buff *skb)
741 {
742 ip6_datagram_recv_common_ctl(sk, msg, skb);
743 ip6_datagram_recv_specific_ctl(sk, msg, skb);
744 }
745 EXPORT_SYMBOL_GPL(ip6_datagram_recv_ctl);
746
ip6_datagram_send_ctl(struct net * net,struct sock * sk,struct msghdr * msg,struct flowi6 * fl6,struct ipcm6_cookie * ipc6,struct sockcm_cookie * sockc)747 int ip6_datagram_send_ctl(struct net *net, struct sock *sk,
748 struct msghdr *msg, struct flowi6 *fl6,
749 struct ipcm6_cookie *ipc6, struct sockcm_cookie *sockc)
750 {
751 struct in6_pktinfo *src_info;
752 struct cmsghdr *cmsg;
753 struct ipv6_rt_hdr *rthdr;
754 struct ipv6_opt_hdr *hdr;
755 struct ipv6_txoptions *opt = ipc6->opt;
756 int len;
757 int err = 0;
758
759 for_each_cmsghdr(cmsg, msg) {
760 int addr_type;
761
762 if (!CMSG_OK(msg, cmsg)) {
763 err = -EINVAL;
764 goto exit_f;
765 }
766
767 if (cmsg->cmsg_level == SOL_SOCKET) {
768 err = __sock_cmsg_send(sk, msg, cmsg, sockc);
769 if (err)
770 return err;
771 continue;
772 }
773
774 if (cmsg->cmsg_level != SOL_IPV6)
775 continue;
776
777 switch (cmsg->cmsg_type) {
778 case IPV6_PKTINFO:
779 case IPV6_2292PKTINFO:
780 {
781 struct net_device *dev = NULL;
782
783 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) {
784 err = -EINVAL;
785 goto exit_f;
786 }
787
788 src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
789
790 if (src_info->ipi6_ifindex) {
791 if (fl6->flowi6_oif &&
792 src_info->ipi6_ifindex != fl6->flowi6_oif)
793 return -EINVAL;
794 fl6->flowi6_oif = src_info->ipi6_ifindex;
795 }
796
797 addr_type = __ipv6_addr_type(&src_info->ipi6_addr);
798
799 rcu_read_lock();
800 if (fl6->flowi6_oif) {
801 dev = dev_get_by_index_rcu(net, fl6->flowi6_oif);
802 if (!dev) {
803 rcu_read_unlock();
804 return -ENODEV;
805 }
806 } else if (addr_type & IPV6_ADDR_LINKLOCAL) {
807 rcu_read_unlock();
808 return -EINVAL;
809 }
810
811 if (addr_type != IPV6_ADDR_ANY) {
812 int strict = __ipv6_addr_src_scope(addr_type) <= IPV6_ADDR_SCOPE_LINKLOCAL;
813 if (!(inet_sk(sk)->freebind || inet_sk(sk)->transparent) &&
814 !ipv6_chk_addr(net, &src_info->ipi6_addr,
815 strict ? dev : NULL, 0) &&
816 !ipv6_chk_acast_addr_src(net, dev,
817 &src_info->ipi6_addr))
818 err = -EINVAL;
819 else
820 fl6->saddr = src_info->ipi6_addr;
821 }
822
823 rcu_read_unlock();
824
825 if (err)
826 goto exit_f;
827
828 break;
829 }
830
831 case IPV6_FLOWINFO:
832 if (cmsg->cmsg_len < CMSG_LEN(4)) {
833 err = -EINVAL;
834 goto exit_f;
835 }
836
837 if (fl6->flowlabel&IPV6_FLOWINFO_MASK) {
838 if ((fl6->flowlabel^*(__be32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) {
839 err = -EINVAL;
840 goto exit_f;
841 }
842 }
843 fl6->flowlabel = IPV6_FLOWINFO_MASK & *(__be32 *)CMSG_DATA(cmsg);
844 break;
845
846 case IPV6_2292HOPOPTS:
847 case IPV6_HOPOPTS:
848 if (opt->hopopt || 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 opt->opt_nflen += len;
864 opt->hopopt = hdr;
865 break;
866
867 case IPV6_2292DSTOPTS:
868 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
869 err = -EINVAL;
870 goto exit_f;
871 }
872
873 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
874 len = ((hdr->hdrlen + 1) << 3);
875 if (cmsg->cmsg_len < CMSG_LEN(len)) {
876 err = -EINVAL;
877 goto exit_f;
878 }
879 if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
880 err = -EPERM;
881 goto exit_f;
882 }
883 if (opt->dst1opt) {
884 err = -EINVAL;
885 goto exit_f;
886 }
887 opt->opt_flen += len;
888 opt->dst1opt = hdr;
889 break;
890
891 case IPV6_DSTOPTS:
892 case IPV6_RTHDRDSTOPTS:
893 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
894 err = -EINVAL;
895 goto exit_f;
896 }
897
898 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
899 len = ((hdr->hdrlen + 1) << 3);
900 if (cmsg->cmsg_len < CMSG_LEN(len)) {
901 err = -EINVAL;
902 goto exit_f;
903 }
904 if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
905 err = -EPERM;
906 goto exit_f;
907 }
908 if (cmsg->cmsg_type == IPV6_DSTOPTS) {
909 opt->opt_flen += len;
910 opt->dst1opt = hdr;
911 } else {
912 opt->opt_nflen += len;
913 opt->dst0opt = hdr;
914 }
915 break;
916
917 case IPV6_2292RTHDR:
918 case IPV6_RTHDR:
919 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) {
920 err = -EINVAL;
921 goto exit_f;
922 }
923
924 rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg);
925
926 switch (rthdr->type) {
927 #if IS_ENABLED(CONFIG_IPV6_MIP6)
928 case IPV6_SRCRT_TYPE_2:
929 if (rthdr->hdrlen != 2 ||
930 rthdr->segments_left != 1) {
931 err = -EINVAL;
932 goto exit_f;
933 }
934 break;
935 #endif
936 default:
937 err = -EINVAL;
938 goto exit_f;
939 }
940
941 len = ((rthdr->hdrlen + 1) << 3);
942
943 if (cmsg->cmsg_len < CMSG_LEN(len)) {
944 err = -EINVAL;
945 goto exit_f;
946 }
947
948 /* segments left must also match */
949 if ((rthdr->hdrlen >> 1) != rthdr->segments_left) {
950 err = -EINVAL;
951 goto exit_f;
952 }
953
954 opt->opt_nflen += len;
955 opt->srcrt = rthdr;
956
957 if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) {
958 int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3);
959
960 opt->opt_nflen += dsthdrlen;
961 opt->dst0opt = opt->dst1opt;
962 opt->dst1opt = NULL;
963 opt->opt_flen -= dsthdrlen;
964 }
965
966 break;
967
968 case IPV6_2292HOPLIMIT:
969 case IPV6_HOPLIMIT:
970 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
971 err = -EINVAL;
972 goto exit_f;
973 }
974
975 ipc6->hlimit = *(int *)CMSG_DATA(cmsg);
976 if (ipc6->hlimit < -1 || ipc6->hlimit > 0xff) {
977 err = -EINVAL;
978 goto exit_f;
979 }
980
981 break;
982
983 case IPV6_TCLASS:
984 {
985 int tc;
986
987 err = -EINVAL;
988 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
989 goto exit_f;
990
991 tc = *(int *)CMSG_DATA(cmsg);
992 if (tc < -1 || tc > 0xff)
993 goto exit_f;
994
995 err = 0;
996 ipc6->tclass = tc;
997
998 break;
999 }
1000
1001 case IPV6_DONTFRAG:
1002 {
1003 int df;
1004
1005 err = -EINVAL;
1006 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
1007 goto exit_f;
1008
1009 df = *(int *)CMSG_DATA(cmsg);
1010 if (df < 0 || df > 1)
1011 goto exit_f;
1012
1013 err = 0;
1014 ipc6->dontfrag = df;
1015
1016 break;
1017 }
1018 default:
1019 net_dbg_ratelimited("invalid cmsg type: %d\n",
1020 cmsg->cmsg_type);
1021 err = -EINVAL;
1022 goto exit_f;
1023 }
1024 }
1025
1026 exit_f:
1027 return err;
1028 }
1029 EXPORT_SYMBOL_GPL(ip6_datagram_send_ctl);
1030
__ip6_dgram_sock_seq_show(struct seq_file * seq,struct sock * sp,__u16 srcp,__u16 destp,int rqueue,int bucket)1031 void __ip6_dgram_sock_seq_show(struct seq_file *seq, struct sock *sp,
1032 __u16 srcp, __u16 destp, int rqueue, int bucket)
1033 {
1034 const struct in6_addr *dest, *src;
1035
1036 dest = &sp->sk_v6_daddr;
1037 src = &sp->sk_v6_rcv_saddr;
1038 seq_printf(seq,
1039 "%5d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1040 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %d\n",
1041 bucket,
1042 src->s6_addr32[0], src->s6_addr32[1],
1043 src->s6_addr32[2], src->s6_addr32[3], srcp,
1044 dest->s6_addr32[0], dest->s6_addr32[1],
1045 dest->s6_addr32[2], dest->s6_addr32[3], destp,
1046 sp->sk_state,
1047 sk_wmem_alloc_get(sp),
1048 rqueue,
1049 0, 0L, 0,
1050 from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)),
1051 0,
1052 sock_i_ino(sp),
1053 refcount_read(&sp->sk_refcnt), sp,
1054 atomic_read(&sp->sk_drops));
1055 }
1056