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
ipv6_mapped_addr_any(const struct in6_addr * a)36 static 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
ip6_datagram_connect(struct sock * sk,struct sockaddr * uaddr,int addr_len)41 int 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 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
104 ipv4_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 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 fl6.daddr = np->daddr;
158 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 np->saddr = fl6.saddr;
183
184 if (ipv6_addr_any(&np->rcv_saddr)) {
185 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;
201 out:
202 fl6_sock_release(flowlabel);
203 return err;
204 }
205
ipv6_icmp_error(struct sock * sk,struct sk_buff * skb,int err,__be16 port,u32 info,u8 * payload)206 void 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
ipv6_local_error(struct sock * sk,int err,struct flowi6 * fl6,u32 info)241 void 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 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
ipv6_local_rxpmtu(struct sock * sk,struct flowi6 * fl6,u32 mtu)280 void 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 iph->daddr = fl6->daddr;
298
299 mtu_info = IP6CBMTU(skb);
300
301 mtu_info->ip6m_mtu = mtu;
302 mtu_info->ip6m_addr.sin6_family = AF_INET6;
303 mtu_info->ip6m_addr.sin6_port = 0;
304 mtu_info->ip6m_addr.sin6_flowinfo = 0;
305 mtu_info->ip6m_addr.sin6_scope_id = fl6->flowi6_oif;
306 mtu_info->ip6m_addr.sin6_addr = ipv6_hdr(skb)->daddr;
307
308 __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
309 skb_reset_transport_header(skb);
310
311 skb = xchg(&np->rxpmtu, skb);
312 kfree_skb(skb);
313 }
314
315 /*
316 * Handle MSG_ERRQUEUE
317 */
ipv6_recv_error(struct sock * sk,struct msghdr * msg,int len,int * addr_len)318 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
319 {
320 struct ipv6_pinfo *np = inet6_sk(sk);
321 struct sock_exterr_skb *serr;
322 struct sk_buff *skb, *skb2;
323 struct sockaddr_in6 *sin;
324 struct {
325 struct sock_extended_err ee;
326 struct sockaddr_in6 offender;
327 } errhdr;
328 int err;
329 int copied;
330
331 err = -EAGAIN;
332 skb = skb_dequeue(&sk->sk_error_queue);
333 if (skb == NULL)
334 goto out;
335
336 copied = skb->len;
337 if (copied > len) {
338 msg->msg_flags |= MSG_TRUNC;
339 copied = len;
340 }
341 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
342 if (err)
343 goto out_free_skb;
344
345 sock_recv_timestamp(msg, sk, skb);
346
347 serr = SKB_EXT_ERR(skb);
348
349 sin = (struct sockaddr_in6 *)msg->msg_name;
350 if (sin) {
351 const unsigned char *nh = skb_network_header(skb);
352 sin->sin6_family = AF_INET6;
353 sin->sin6_flowinfo = 0;
354 sin->sin6_port = serr->port;
355 sin->sin6_scope_id = 0;
356 if (skb->protocol == htons(ETH_P_IPV6)) {
357 sin->sin6_addr =
358 *(struct in6_addr *)(nh + serr->addr_offset);
359 if (np->sndflow)
360 sin->sin6_flowinfo =
361 (*(__be32 *)(nh + serr->addr_offset - 24) &
362 IPV6_FLOWINFO_MASK);
363 if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
364 sin->sin6_scope_id = IP6CB(skb)->iif;
365 } else {
366 ipv6_addr_set_v4mapped(*(__be32 *)(nh + serr->addr_offset),
367 &sin->sin6_addr);
368 }
369 *addr_len = sizeof(*sin);
370 }
371
372 memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
373 sin = &errhdr.offender;
374 sin->sin6_family = AF_UNSPEC;
375 if (serr->ee.ee_origin != SO_EE_ORIGIN_LOCAL) {
376 sin->sin6_family = AF_INET6;
377 sin->sin6_flowinfo = 0;
378 sin->sin6_port = 0;
379 sin->sin6_scope_id = 0;
380 if (skb->protocol == htons(ETH_P_IPV6)) {
381 sin->sin6_addr = ipv6_hdr(skb)->saddr;
382 if (np->rxopt.all)
383 datagram_recv_ctl(sk, msg, skb);
384 if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
385 sin->sin6_scope_id = IP6CB(skb)->iif;
386 } else {
387 struct inet_sock *inet = inet_sk(sk);
388
389 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
390 &sin->sin6_addr);
391 if (inet->cmsg_flags)
392 ip_cmsg_recv(msg, skb);
393 }
394 }
395
396 put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr);
397
398 /* Now we could try to dump offended packet options */
399
400 msg->msg_flags |= MSG_ERRQUEUE;
401 err = copied;
402
403 /* Reset and regenerate socket error */
404 spin_lock_bh(&sk->sk_error_queue.lock);
405 sk->sk_err = 0;
406 if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
407 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
408 spin_unlock_bh(&sk->sk_error_queue.lock);
409 sk->sk_error_report(sk);
410 } else {
411 spin_unlock_bh(&sk->sk_error_queue.lock);
412 }
413
414 out_free_skb:
415 kfree_skb(skb);
416 out:
417 return err;
418 }
419
420 /*
421 * Handle IPV6_RECVPATHMTU
422 */
ipv6_recv_rxpmtu(struct sock * sk,struct msghdr * msg,int len,int * addr_len)423 int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len,
424 int *addr_len)
425 {
426 struct ipv6_pinfo *np = inet6_sk(sk);
427 struct sk_buff *skb;
428 struct sockaddr_in6 *sin;
429 struct ip6_mtuinfo mtu_info;
430 int err;
431 int copied;
432
433 err = -EAGAIN;
434 skb = xchg(&np->rxpmtu, NULL);
435 if (skb == NULL)
436 goto out;
437
438 copied = skb->len;
439 if (copied > len) {
440 msg->msg_flags |= MSG_TRUNC;
441 copied = len;
442 }
443 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
444 if (err)
445 goto out_free_skb;
446
447 sock_recv_timestamp(msg, sk, skb);
448
449 memcpy(&mtu_info, IP6CBMTU(skb), sizeof(mtu_info));
450
451 sin = (struct sockaddr_in6 *)msg->msg_name;
452 if (sin) {
453 sin->sin6_family = AF_INET6;
454 sin->sin6_flowinfo = 0;
455 sin->sin6_port = 0;
456 sin->sin6_scope_id = mtu_info.ip6m_addr.sin6_scope_id;
457 sin->sin6_addr = mtu_info.ip6m_addr.sin6_addr;
458 *addr_len = sizeof(*sin);
459 }
460
461 put_cmsg(msg, SOL_IPV6, IPV6_PATHMTU, sizeof(mtu_info), &mtu_info);
462
463 err = copied;
464
465 out_free_skb:
466 kfree_skb(skb);
467 out:
468 return err;
469 }
470
471
datagram_recv_ctl(struct sock * sk,struct msghdr * msg,struct sk_buff * skb)472 int 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 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 = ipv6_tclass(ipv6_hdr(skb));
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 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 __be16 *ports = (__be16 *) 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 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
datagram_send_ctl(struct net * net,struct sock * sk,struct msghdr * msg,struct flowi6 * fl6,struct ipv6_txoptions * opt,int * hlimit,int * tclass,int * dontfrag)602 int 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)->freebind || inet_sk(sk)->transparent) &&
662 !ipv6_chk_addr(net, &src_info->ipi6_addr,
663 strict ? dev : NULL, 0))
664 err = -EINVAL;
665 else
666 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
874 exit_f:
875 return err;
876 }
877