[IPV6]: Check outgoing interface even if source address is unspecified.
[linux-3.10.git] / net / ipv6 / datagram.c
1 /*
2  *      common UDP/RAW code
3  *      Linux INET6 implementation
4  *
5  *      Authors:
6  *      Pedro Roque             <roque@di.fc.ul.pt>
7  *
8  *      $Id: datagram.c,v 1.24 2002/02/01 22:01:04 davem Exp $
9  *
10  *      This program is free software; you can redistribute it and/or
11  *      modify it under the terms of the GNU General Public License
12  *      as published by the Free Software Foundation; either version
13  *      2 of the License, or (at your option) any later version.
14  */
15
16 #include <linux/capability.h>
17 #include <linux/errno.h>
18 #include <linux/types.h>
19 #include <linux/kernel.h>
20 #include <linux/interrupt.h>
21 #include <linux/socket.h>
22 #include <linux/sockios.h>
23 #include <linux/in6.h>
24 #include <linux/ipv6.h>
25 #include <linux/route.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
34 #include <linux/errqueue.h>
35 #include <asm/uaccess.h>
36
37 int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
38 {
39         struct sockaddr_in6     *usin = (struct sockaddr_in6 *) uaddr;
40         struct inet_sock        *inet = inet_sk(sk);
41         struct ipv6_pinfo       *np = inet6_sk(sk);
42         struct in6_addr         *daddr, *final_p = NULL, final;
43         struct dst_entry        *dst;
44         struct flowi            fl;
45         struct ip6_flowlabel    *flowlabel = NULL;
46         int                     addr_type;
47         int                     err;
48
49         if (usin->sin6_family == AF_INET) {
50                 if (__ipv6_only_sock(sk))
51                         return -EAFNOSUPPORT;
52                 err = ip4_datagram_connect(sk, uaddr, addr_len);
53                 goto ipv4_connected;
54         }
55
56         if (addr_len < SIN6_LEN_RFC2133)
57                 return -EINVAL;
58
59         if (usin->sin6_family != AF_INET6)
60                 return -EAFNOSUPPORT;
61
62         memset(&fl, 0, sizeof(fl));
63         if (np->sndflow) {
64                 fl.fl6_flowlabel = usin->sin6_flowinfo&IPV6_FLOWINFO_MASK;
65                 if (fl.fl6_flowlabel&IPV6_FLOWLABEL_MASK) {
66                         flowlabel = fl6_sock_lookup(sk, fl.fl6_flowlabel);
67                         if (flowlabel == NULL)
68                                 return -EINVAL;
69                         ipv6_addr_copy(&usin->sin6_addr, &flowlabel->dst);
70                 }
71         }
72
73         addr_type = ipv6_addr_type(&usin->sin6_addr);
74
75         if (addr_type == IPV6_ADDR_ANY) {
76                 /*
77                  *      connect to self
78                  */
79                 usin->sin6_addr.s6_addr[15] = 0x01;
80         }
81
82         daddr = &usin->sin6_addr;
83
84         if (addr_type == IPV6_ADDR_MAPPED) {
85                 struct sockaddr_in sin;
86
87                 if (__ipv6_only_sock(sk)) {
88                         err = -ENETUNREACH;
89                         goto out;
90                 }
91                 sin.sin_family = AF_INET;
92                 sin.sin_addr.s_addr = daddr->s6_addr32[3];
93                 sin.sin_port = usin->sin6_port;
94
95                 err = ip4_datagram_connect(sk,
96                                            (struct sockaddr*) &sin,
97                                            sizeof(sin));
98
99 ipv4_connected:
100                 if (err)
101                         goto out;
102
103                 ipv6_addr_set(&np->daddr, 0, 0, htonl(0x0000ffff), inet->daddr);
104
105                 if (ipv6_addr_any(&np->saddr)) {
106                         ipv6_addr_set(&np->saddr, 0, 0, htonl(0x0000ffff),
107                                       inet->saddr);
108                 }
109
110                 if (ipv6_addr_any(&np->rcv_saddr)) {
111                         ipv6_addr_set(&np->rcv_saddr, 0, 0, htonl(0x0000ffff),
112                                       inet->rcv_saddr);
113                 }
114                 goto out;
115         }
116
117         if (addr_type&IPV6_ADDR_LINKLOCAL) {
118                 if (addr_len >= sizeof(struct sockaddr_in6) &&
119                     usin->sin6_scope_id) {
120                         if (sk->sk_bound_dev_if &&
121                             sk->sk_bound_dev_if != usin->sin6_scope_id) {
122                                 err = -EINVAL;
123                                 goto out;
124                         }
125                         sk->sk_bound_dev_if = usin->sin6_scope_id;
126                 }
127
128                 if (!sk->sk_bound_dev_if && (addr_type & IPV6_ADDR_MULTICAST))
129                         sk->sk_bound_dev_if = np->mcast_oif;
130
131                 /* Connect to link-local address requires an interface */
132                 if (!sk->sk_bound_dev_if) {
133                         err = -EINVAL;
134                         goto out;
135                 }
136         }
137
138         ipv6_addr_copy(&np->daddr, daddr);
139         np->flow_label = fl.fl6_flowlabel;
140
141         inet->dport = usin->sin6_port;
142
143         /*
144          *      Check for a route to destination an obtain the
145          *      destination cache for it.
146          */
147
148         fl.proto = sk->sk_protocol;
149         ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
150         ipv6_addr_copy(&fl.fl6_src, &np->saddr);
151         fl.oif = sk->sk_bound_dev_if;
152         fl.fl_ip_dport = inet->dport;
153         fl.fl_ip_sport = inet->sport;
154
155         if (!fl.oif && (addr_type&IPV6_ADDR_MULTICAST))
156                 fl.oif = np->mcast_oif;
157
158         security_sk_classify_flow(sk, &fl);
159
160         if (flowlabel) {
161                 if (flowlabel->opt && flowlabel->opt->srcrt) {
162                         struct rt0_hdr *rt0 = (struct rt0_hdr *) flowlabel->opt->srcrt;
163                         ipv6_addr_copy(&final, &fl.fl6_dst);
164                         ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
165                         final_p = &final;
166                 }
167         } else if (np->opt && np->opt->srcrt) {
168                 struct rt0_hdr *rt0 = (struct rt0_hdr *)np->opt->srcrt;
169                 ipv6_addr_copy(&final, &fl.fl6_dst);
170                 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
171                 final_p = &final;
172         }
173
174         err = ip6_dst_lookup(sk, &dst, &fl);
175         if (err)
176                 goto out;
177         if (final_p)
178                 ipv6_addr_copy(&fl.fl6_dst, final_p);
179
180         if ((err = __xfrm_lookup(&dst, &fl, sk, XFRM_LOOKUP_WAIT)) < 0) {
181                 if (err == -EREMOTE)
182                         err = ip6_dst_blackhole(sk, &dst, &fl);
183                 if (err < 0)
184                         goto out;
185         }
186
187         /* source address lookup done in ip6_dst_lookup */
188
189         if (ipv6_addr_any(&np->saddr))
190                 ipv6_addr_copy(&np->saddr, &fl.fl6_src);
191
192         if (ipv6_addr_any(&np->rcv_saddr)) {
193                 ipv6_addr_copy(&np->rcv_saddr, &fl.fl6_src);
194                 inet->rcv_saddr = LOOPBACK4_IPV6;
195         }
196
197         ip6_dst_store(sk, dst,
198                       ipv6_addr_equal(&fl.fl6_dst, &np->daddr) ?
199                       &np->daddr : NULL,
200 #ifdef CONFIG_IPV6_SUBTREES
201                       ipv6_addr_equal(&fl.fl6_src, &np->saddr) ?
202                       &np->saddr :
203 #endif
204                       NULL);
205
206         sk->sk_state = TCP_ESTABLISHED;
207 out:
208         fl6_sock_release(flowlabel);
209         return err;
210 }
211
212 void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
213                      __be16 port, u32 info, u8 *payload)
214 {
215         struct ipv6_pinfo *np  = inet6_sk(sk);
216         struct icmp6hdr *icmph = icmp6_hdr(skb);
217         struct sock_exterr_skb *serr;
218
219         if (!np->recverr)
220                 return;
221
222         skb = skb_clone(skb, GFP_ATOMIC);
223         if (!skb)
224                 return;
225
226         serr = SKB_EXT_ERR(skb);
227         serr->ee.ee_errno = err;
228         serr->ee.ee_origin = SO_EE_ORIGIN_ICMP6;
229         serr->ee.ee_type = icmph->icmp6_type;
230         serr->ee.ee_code = icmph->icmp6_code;
231         serr->ee.ee_pad = 0;
232         serr->ee.ee_info = info;
233         serr->ee.ee_data = 0;
234         serr->addr_offset = (u8 *)&(((struct ipv6hdr *)(icmph + 1))->daddr) -
235                                   skb_network_header(skb);
236         serr->port = port;
237
238         __skb_pull(skb, payload - skb->data);
239         skb_reset_transport_header(skb);
240
241         if (sock_queue_err_skb(sk, skb))
242                 kfree_skb(skb);
243 }
244
245 void ipv6_local_error(struct sock *sk, int err, struct flowi *fl, u32 info)
246 {
247         struct ipv6_pinfo *np = inet6_sk(sk);
248         struct sock_exterr_skb *serr;
249         struct ipv6hdr *iph;
250         struct sk_buff *skb;
251
252         if (!np->recverr)
253                 return;
254
255         skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
256         if (!skb)
257                 return;
258
259         skb_put(skb, sizeof(struct ipv6hdr));
260         skb_reset_network_header(skb);
261         iph = ipv6_hdr(skb);
262         ipv6_addr_copy(&iph->daddr, &fl->fl6_dst);
263
264         serr = SKB_EXT_ERR(skb);
265         serr->ee.ee_errno = err;
266         serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
267         serr->ee.ee_type = 0;
268         serr->ee.ee_code = 0;
269         serr->ee.ee_pad = 0;
270         serr->ee.ee_info = info;
271         serr->ee.ee_data = 0;
272         serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
273         serr->port = fl->fl_ip_dport;
274
275         __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
276         skb_reset_transport_header(skb);
277
278         if (sock_queue_err_skb(sk, skb))
279                 kfree_skb(skb);
280 }
281
282 /*
283  *      Handle MSG_ERRQUEUE
284  */
285 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len)
286 {
287         struct ipv6_pinfo *np = inet6_sk(sk);
288         struct sock_exterr_skb *serr;
289         struct sk_buff *skb, *skb2;
290         struct sockaddr_in6 *sin;
291         struct {
292                 struct sock_extended_err ee;
293                 struct sockaddr_in6      offender;
294         } errhdr;
295         int err;
296         int copied;
297
298         err = -EAGAIN;
299         skb = skb_dequeue(&sk->sk_error_queue);
300         if (skb == NULL)
301                 goto out;
302
303         copied = skb->len;
304         if (copied > len) {
305                 msg->msg_flags |= MSG_TRUNC;
306                 copied = len;
307         }
308         err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
309         if (err)
310                 goto out_free_skb;
311
312         sock_recv_timestamp(msg, sk, skb);
313
314         serr = SKB_EXT_ERR(skb);
315
316         sin = (struct sockaddr_in6 *)msg->msg_name;
317         if (sin) {
318                 const unsigned char *nh = skb_network_header(skb);
319                 sin->sin6_family = AF_INET6;
320                 sin->sin6_flowinfo = 0;
321                 sin->sin6_port = serr->port;
322                 sin->sin6_scope_id = 0;
323                 if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6) {
324                         ipv6_addr_copy(&sin->sin6_addr,
325                                   (struct in6_addr *)(nh + serr->addr_offset));
326                         if (np->sndflow)
327                                 sin->sin6_flowinfo =
328                                         (*(__be32 *)(nh + serr->addr_offset - 24) &
329                                          IPV6_FLOWINFO_MASK);
330                         if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
331                                 sin->sin6_scope_id = IP6CB(skb)->iif;
332                 } else {
333                         ipv6_addr_set(&sin->sin6_addr, 0, 0,
334                                       htonl(0xffff),
335                                       *(__be32 *)(nh + serr->addr_offset));
336                 }
337         }
338
339         memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
340         sin = &errhdr.offender;
341         sin->sin6_family = AF_UNSPEC;
342         if (serr->ee.ee_origin != SO_EE_ORIGIN_LOCAL) {
343                 sin->sin6_family = AF_INET6;
344                 sin->sin6_flowinfo = 0;
345                 sin->sin6_scope_id = 0;
346                 if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6) {
347                         ipv6_addr_copy(&sin->sin6_addr, &ipv6_hdr(skb)->saddr);
348                         if (np->rxopt.all)
349                                 datagram_recv_ctl(sk, msg, skb);
350                         if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
351                                 sin->sin6_scope_id = IP6CB(skb)->iif;
352                 } else {
353                         struct inet_sock *inet = inet_sk(sk);
354
355                         ipv6_addr_set(&sin->sin6_addr, 0, 0,
356                                       htonl(0xffff), ip_hdr(skb)->saddr);
357                         if (inet->cmsg_flags)
358                                 ip_cmsg_recv(msg, skb);
359                 }
360         }
361
362         put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr);
363
364         /* Now we could try to dump offended packet options */
365
366         msg->msg_flags |= MSG_ERRQUEUE;
367         err = copied;
368
369         /* Reset and regenerate socket error */
370         spin_lock_bh(&sk->sk_error_queue.lock);
371         sk->sk_err = 0;
372         if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
373                 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
374                 spin_unlock_bh(&sk->sk_error_queue.lock);
375                 sk->sk_error_report(sk);
376         } else {
377                 spin_unlock_bh(&sk->sk_error_queue.lock);
378         }
379
380 out_free_skb:
381         kfree_skb(skb);
382 out:
383         return err;
384 }
385
386
387
388 int datagram_recv_ctl(struct sock *sk, struct msghdr *msg, struct sk_buff *skb)
389 {
390         struct ipv6_pinfo *np = inet6_sk(sk);
391         struct inet6_skb_parm *opt = IP6CB(skb);
392         unsigned char *nh = skb_network_header(skb);
393
394         if (np->rxopt.bits.rxinfo) {
395                 struct in6_pktinfo src_info;
396
397                 src_info.ipi6_ifindex = opt->iif;
398                 ipv6_addr_copy(&src_info.ipi6_addr, &ipv6_hdr(skb)->daddr);
399                 put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
400         }
401
402         if (np->rxopt.bits.rxhlim) {
403                 int hlim = ipv6_hdr(skb)->hop_limit;
404                 put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
405         }
406
407         if (np->rxopt.bits.rxtclass) {
408                 int tclass = (ntohl(*(__be32 *)ipv6_hdr(skb)) >> 20) & 0xff;
409                 put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
410         }
411
412         if (np->rxopt.bits.rxflow && (*(__be32 *)nh & IPV6_FLOWINFO_MASK)) {
413                 __be32 flowinfo = *(__be32 *)nh & IPV6_FLOWINFO_MASK;
414                 put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
415         }
416
417         /* HbH is allowed only once */
418         if (np->rxopt.bits.hopopts && opt->hop) {
419                 u8 *ptr = nh + opt->hop;
420                 put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr);
421         }
422
423         if (opt->lastopt &&
424             (np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) {
425                 /*
426                  * Silly enough, but we need to reparse in order to
427                  * report extension headers (except for HbH)
428                  * in order.
429                  *
430                  * Also note that IPV6_RECVRTHDRDSTOPTS is NOT
431                  * (and WILL NOT be) defined because
432                  * IPV6_RECVDSTOPTS is more generic. --yoshfuji
433                  */
434                 unsigned int off = sizeof(struct ipv6hdr);
435                 u8 nexthdr = ipv6_hdr(skb)->nexthdr;
436
437                 while (off <= opt->lastopt) {
438                         unsigned len;
439                         u8 *ptr = nh + off;
440
441                         switch(nexthdr) {
442                         case IPPROTO_DSTOPTS:
443                                 nexthdr = ptr[0];
444                                 len = (ptr[1] + 1) << 3;
445                                 if (np->rxopt.bits.dstopts)
446                                         put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, ptr);
447                                 break;
448                         case IPPROTO_ROUTING:
449                                 nexthdr = ptr[0];
450                                 len = (ptr[1] + 1) << 3;
451                                 if (np->rxopt.bits.srcrt)
452                                         put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, ptr);
453                                 break;
454                         case IPPROTO_AH:
455                                 nexthdr = ptr[0];
456                                 len = (ptr[1] + 2) << 2;
457                                 break;
458                         default:
459                                 nexthdr = ptr[0];
460                                 len = (ptr[1] + 1) << 3;
461                                 break;
462                         }
463
464                         off += len;
465                 }
466         }
467
468         /* socket options in old style */
469         if (np->rxopt.bits.rxoinfo) {
470                 struct in6_pktinfo src_info;
471
472                 src_info.ipi6_ifindex = opt->iif;
473                 ipv6_addr_copy(&src_info.ipi6_addr, &ipv6_hdr(skb)->daddr);
474                 put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
475         }
476         if (np->rxopt.bits.rxohlim) {
477                 int hlim = ipv6_hdr(skb)->hop_limit;
478                 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
479         }
480         if (np->rxopt.bits.ohopopts && opt->hop) {
481                 u8 *ptr = nh + opt->hop;
482                 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, (ptr[1]+1)<<3, ptr);
483         }
484         if (np->rxopt.bits.odstopts && opt->dst0) {
485                 u8 *ptr = nh + opt->dst0;
486                 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
487         }
488         if (np->rxopt.bits.osrcrt && opt->srcrt) {
489                 struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt);
490                 put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, (rthdr->hdrlen+1) << 3, rthdr);
491         }
492         if (np->rxopt.bits.odstopts && opt->dst1) {
493                 u8 *ptr = nh + opt->dst1;
494                 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
495         }
496         return 0;
497 }
498
499 int datagram_send_ctl(struct msghdr *msg, struct flowi *fl,
500                       struct ipv6_txoptions *opt,
501                       int *hlimit, int *tclass)
502 {
503         struct in6_pktinfo *src_info;
504         struct cmsghdr *cmsg;
505         struct ipv6_rt_hdr *rthdr;
506         struct ipv6_opt_hdr *hdr;
507         int len;
508         int err = 0;
509
510         for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
511                 int addr_type;
512
513                 if (!CMSG_OK(msg, cmsg)) {
514                         err = -EINVAL;
515                         goto exit_f;
516                 }
517
518                 if (cmsg->cmsg_level != SOL_IPV6)
519                         continue;
520
521                 switch (cmsg->cmsg_type) {
522                 case IPV6_PKTINFO:
523                 case IPV6_2292PKTINFO:
524                     {
525                         struct net_device *dev = NULL;
526
527                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) {
528                                 err = -EINVAL;
529                                 goto exit_f;
530                         }
531
532                         src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
533
534                         if (src_info->ipi6_ifindex) {
535                                 if (fl->oif && src_info->ipi6_ifindex != fl->oif)
536                                         return -EINVAL;
537                                 fl->oif = src_info->ipi6_ifindex;
538                         }
539
540                         addr_type = __ipv6_addr_type(&src_info->ipi6_addr);
541
542                         if (fl->oif) {
543                                 dev = dev_get_by_index(&init_net, fl->oif);
544                                 if (!dev)
545                                         return -ENODEV;
546                         } else if (addr_type & IPV6_ADDR_LINKLOCAL)
547                                 return -EINVAL;
548
549                         if (addr_type != IPV6_ADDR_ANY) {
550                                 int strict = __ipv6_addr_src_scope(addr_type) <= IPV6_ADDR_SCOPE_LINKLOCAL;
551                                 if (!ipv6_chk_addr(&init_net, &src_info->ipi6_addr,
552                                                    strict ? dev : NULL, 0))
553                                         err = -EINVAL;
554                                 else
555                                         ipv6_addr_copy(&fl->fl6_src, &src_info->ipi6_addr);
556                         }
557
558                         if (dev)
559                                 dev_put(dev);
560
561                         if (err)
562                                 goto exit_f;
563
564                         break;
565                     }
566
567                 case IPV6_FLOWINFO:
568                         if (cmsg->cmsg_len < CMSG_LEN(4)) {
569                                 err = -EINVAL;
570                                 goto exit_f;
571                         }
572
573                         if (fl->fl6_flowlabel&IPV6_FLOWINFO_MASK) {
574                                 if ((fl->fl6_flowlabel^*(__be32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) {
575                                         err = -EINVAL;
576                                         goto exit_f;
577                                 }
578                         }
579                         fl->fl6_flowlabel = IPV6_FLOWINFO_MASK & *(__be32 *)CMSG_DATA(cmsg);
580                         break;
581
582                 case IPV6_2292HOPOPTS:
583                 case IPV6_HOPOPTS:
584                         if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
585                                 err = -EINVAL;
586                                 goto exit_f;
587                         }
588
589                         hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
590                         len = ((hdr->hdrlen + 1) << 3);
591                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
592                                 err = -EINVAL;
593                                 goto exit_f;
594                         }
595                         if (!capable(CAP_NET_RAW)) {
596                                 err = -EPERM;
597                                 goto exit_f;
598                         }
599                         opt->opt_nflen += len;
600                         opt->hopopt = hdr;
601                         break;
602
603                 case IPV6_2292DSTOPTS:
604                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
605                                 err = -EINVAL;
606                                 goto exit_f;
607                         }
608
609                         hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
610                         len = ((hdr->hdrlen + 1) << 3);
611                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
612                                 err = -EINVAL;
613                                 goto exit_f;
614                         }
615                         if (!capable(CAP_NET_RAW)) {
616                                 err = -EPERM;
617                                 goto exit_f;
618                         }
619                         if (opt->dst1opt) {
620                                 err = -EINVAL;
621                                 goto exit_f;
622                         }
623                         opt->opt_flen += len;
624                         opt->dst1opt = hdr;
625                         break;
626
627                 case IPV6_DSTOPTS:
628                 case IPV6_RTHDRDSTOPTS:
629                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
630                                 err = -EINVAL;
631                                 goto exit_f;
632                         }
633
634                         hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
635                         len = ((hdr->hdrlen + 1) << 3);
636                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
637                                 err = -EINVAL;
638                                 goto exit_f;
639                         }
640                         if (!capable(CAP_NET_RAW)) {
641                                 err = -EPERM;
642                                 goto exit_f;
643                         }
644                         if (cmsg->cmsg_type == IPV6_DSTOPTS) {
645                                 opt->opt_flen += len;
646                                 opt->dst1opt = hdr;
647                         } else {
648                                 opt->opt_nflen += len;
649                                 opt->dst0opt = hdr;
650                         }
651                         break;
652
653                 case IPV6_2292RTHDR:
654                 case IPV6_RTHDR:
655                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) {
656                                 err = -EINVAL;
657                                 goto exit_f;
658                         }
659
660                         rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg);
661
662                         switch (rthdr->type) {
663 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
664                         case IPV6_SRCRT_TYPE_2:
665                                 break;
666 #endif
667                         default:
668                                 err = -EINVAL;
669                                 goto exit_f;
670                         }
671
672                         len = ((rthdr->hdrlen + 1) << 3);
673
674                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
675                                 err = -EINVAL;
676                                 goto exit_f;
677                         }
678
679                         /* segments left must also match */
680                         if ((rthdr->hdrlen >> 1) != rthdr->segments_left) {
681                                 err = -EINVAL;
682                                 goto exit_f;
683                         }
684
685                         opt->opt_nflen += len;
686                         opt->srcrt = rthdr;
687
688                         if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) {
689                                 int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3);
690
691                                 opt->opt_nflen += dsthdrlen;
692                                 opt->dst0opt = opt->dst1opt;
693                                 opt->dst1opt = NULL;
694                                 opt->opt_flen -= dsthdrlen;
695                         }
696
697                         break;
698
699                 case IPV6_2292HOPLIMIT:
700                 case IPV6_HOPLIMIT:
701                         if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
702                                 err = -EINVAL;
703                                 goto exit_f;
704                         }
705
706                         *hlimit = *(int *)CMSG_DATA(cmsg);
707                         break;
708
709                 case IPV6_TCLASS:
710                     {
711                         int tc;
712
713                         err = -EINVAL;
714                         if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
715                                 goto exit_f;
716                         }
717
718                         tc = *(int *)CMSG_DATA(cmsg);
719                         if (tc < -1 || tc > 0xff)
720                                 goto exit_f;
721
722                         err = 0;
723                         *tclass = tc;
724
725                         break;
726                     }
727                 default:
728                         LIMIT_NETDEBUG(KERN_DEBUG "invalid cmsg type: %d\n",
729                                        cmsg->cmsg_type);
730                         err = -EINVAL;
731                         break;
732                 }
733         }
734
735 exit_f:
736         return err;
737 }