Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
[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  *      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
25 #include <net/ipv6.h>
26 #include <net/ndisc.h>
27 #include <net/addrconf.h>
28 #include <net/transp_v6.h>
29 #include <net/ip6_route.h>
30 #include <net/tcp_states.h>
31
32 #include <linux/errqueue.h>
33 #include <asm/uaccess.h>
34
35 int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
36 {
37         struct sockaddr_in6     *usin = (struct sockaddr_in6 *) uaddr;
38         struct inet_sock        *inet = inet_sk(sk);
39         struct ipv6_pinfo       *np = inet6_sk(sk);
40         struct in6_addr         *daddr, *final_p = NULL, final;
41         struct dst_entry        *dst;
42         struct flowi            fl;
43         struct ip6_flowlabel    *flowlabel = NULL;
44         int                     addr_type;
45         int                     err;
46
47         if (usin->sin6_family == AF_INET) {
48                 if (__ipv6_only_sock(sk))
49                         return -EAFNOSUPPORT;
50                 err = ip4_datagram_connect(sk, uaddr, addr_len);
51                 goto ipv4_connected;
52         }
53
54         if (addr_len < SIN6_LEN_RFC2133)
55                 return -EINVAL;
56
57         if (usin->sin6_family != AF_INET6)
58                 return -EAFNOSUPPORT;
59
60         memset(&fl, 0, sizeof(fl));
61         if (np->sndflow) {
62                 fl.fl6_flowlabel = usin->sin6_flowinfo&IPV6_FLOWINFO_MASK;
63                 if (fl.fl6_flowlabel&IPV6_FLOWLABEL_MASK) {
64                         flowlabel = fl6_sock_lookup(sk, fl.fl6_flowlabel);
65                         if (flowlabel == NULL)
66                                 return -EINVAL;
67                         ipv6_addr_copy(&usin->sin6_addr, &flowlabel->dst);
68                 }
69         }
70
71         addr_type = ipv6_addr_type(&usin->sin6_addr);
72
73         if (addr_type == IPV6_ADDR_ANY) {
74                 /*
75                  *      connect to self
76                  */
77                 usin->sin6_addr.s6_addr[15] = 0x01;
78         }
79
80         daddr = &usin->sin6_addr;
81
82         if (addr_type == IPV6_ADDR_MAPPED) {
83                 struct sockaddr_in sin;
84
85                 if (__ipv6_only_sock(sk)) {
86                         err = -ENETUNREACH;
87                         goto out;
88                 }
89                 sin.sin_family = AF_INET;
90                 sin.sin_addr.s_addr = daddr->s6_addr32[3];
91                 sin.sin_port = usin->sin6_port;
92
93                 err = ip4_datagram_connect(sk,
94                                            (struct sockaddr*) &sin,
95                                            sizeof(sin));
96
97 ipv4_connected:
98                 if (err)
99                         goto out;
100
101                 ipv6_addr_set(&np->daddr, 0, 0, htonl(0x0000ffff), inet->daddr);
102
103                 if (ipv6_addr_any(&np->saddr)) {
104                         ipv6_addr_set(&np->saddr, 0, 0, htonl(0x0000ffff),
105                                       inet->saddr);
106                 }
107
108                 if (ipv6_addr_any(&np->rcv_saddr)) {
109                         ipv6_addr_set(&np->rcv_saddr, 0, 0, htonl(0x0000ffff),
110                                       inet->rcv_saddr);
111                 }
112                 goto out;
113         }
114
115         if (addr_type&IPV6_ADDR_LINKLOCAL) {
116                 if (addr_len >= sizeof(struct sockaddr_in6) &&
117                     usin->sin6_scope_id) {
118                         if (sk->sk_bound_dev_if &&
119                             sk->sk_bound_dev_if != usin->sin6_scope_id) {
120                                 err = -EINVAL;
121                                 goto out;
122                         }
123                         sk->sk_bound_dev_if = usin->sin6_scope_id;
124                 }
125
126                 if (!sk->sk_bound_dev_if && (addr_type & IPV6_ADDR_MULTICAST))
127                         sk->sk_bound_dev_if = np->mcast_oif;
128
129                 /* Connect to link-local address requires an interface */
130                 if (!sk->sk_bound_dev_if) {
131                         err = -EINVAL;
132                         goto out;
133                 }
134         }
135
136         ipv6_addr_copy(&np->daddr, daddr);
137         np->flow_label = fl.fl6_flowlabel;
138
139         inet->dport = usin->sin6_port;
140
141         /*
142          *      Check for a route to destination an obtain the
143          *      destination cache for it.
144          */
145
146         fl.proto = sk->sk_protocol;
147         ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
148         ipv6_addr_copy(&fl.fl6_src, &np->saddr);
149         fl.oif = sk->sk_bound_dev_if;
150         fl.fl_ip_dport = inet->dport;
151         fl.fl_ip_sport = inet->sport;
152
153         if (!fl.oif && (addr_type&IPV6_ADDR_MULTICAST))
154                 fl.oif = np->mcast_oif;
155
156         security_sk_classify_flow(sk, &fl);
157
158         if (flowlabel) {
159                 if (flowlabel->opt && flowlabel->opt->srcrt) {
160                         struct rt0_hdr *rt0 = (struct rt0_hdr *) flowlabel->opt->srcrt;
161                         ipv6_addr_copy(&final, &fl.fl6_dst);
162                         ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
163                         final_p = &final;
164                 }
165         } else if (np->opt && np->opt->srcrt) {
166                 struct rt0_hdr *rt0 = (struct rt0_hdr *)np->opt->srcrt;
167                 ipv6_addr_copy(&final, &fl.fl6_dst);
168                 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
169                 final_p = &final;
170         }
171
172         err = ip6_dst_lookup(sk, &dst, &fl);
173         if (err)
174                 goto out;
175         if (final_p)
176                 ipv6_addr_copy(&fl.fl6_dst, final_p);
177
178         if ((err = __xfrm_lookup(&dst, &fl, sk, XFRM_LOOKUP_WAIT)) < 0) {
179                 if (err == -EREMOTE)
180                         err = ip6_dst_blackhole(sk, &dst, &fl);
181                 if (err < 0)
182                         goto out;
183         }
184
185         /* source address lookup done in ip6_dst_lookup */
186
187         if (ipv6_addr_any(&np->saddr))
188                 ipv6_addr_copy(&np->saddr, &fl.fl6_src);
189
190         if (ipv6_addr_any(&np->rcv_saddr)) {
191                 ipv6_addr_copy(&np->rcv_saddr, &fl.fl6_src);
192                 inet->rcv_saddr = LOOPBACK4_IPV6;
193         }
194
195         ip6_dst_store(sk, dst,
196                       ipv6_addr_equal(&fl.fl6_dst, &np->daddr) ?
197                       &np->daddr : NULL,
198 #ifdef CONFIG_IPV6_SUBTREES
199                       ipv6_addr_equal(&fl.fl6_src, &np->saddr) ?
200                       &np->saddr :
201 #endif
202                       NULL);
203
204         sk->sk_state = TCP_ESTABLISHED;
205 out:
206         fl6_sock_release(flowlabel);
207         return err;
208 }
209
210 void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
211                      __be16 port, u32 info, u8 *payload)
212 {
213         struct ipv6_pinfo *np  = inet6_sk(sk);
214         struct icmp6hdr *icmph = icmp6_hdr(skb);
215         struct sock_exterr_skb *serr;
216
217         if (!np->recverr)
218                 return;
219
220         skb = skb_clone(skb, GFP_ATOMIC);
221         if (!skb)
222                 return;
223
224         serr = SKB_EXT_ERR(skb);
225         serr->ee.ee_errno = err;
226         serr->ee.ee_origin = SO_EE_ORIGIN_ICMP6;
227         serr->ee.ee_type = icmph->icmp6_type;
228         serr->ee.ee_code = icmph->icmp6_code;
229         serr->ee.ee_pad = 0;
230         serr->ee.ee_info = info;
231         serr->ee.ee_data = 0;
232         serr->addr_offset = (u8 *)&(((struct ipv6hdr *)(icmph + 1))->daddr) -
233                                   skb_network_header(skb);
234         serr->port = port;
235
236         __skb_pull(skb, payload - skb->data);
237         skb_reset_transport_header(skb);
238
239         if (sock_queue_err_skb(sk, skb))
240                 kfree_skb(skb);
241 }
242
243 void ipv6_local_error(struct sock *sk, int err, struct flowi *fl, u32 info)
244 {
245         struct ipv6_pinfo *np = inet6_sk(sk);
246         struct sock_exterr_skb *serr;
247         struct ipv6hdr *iph;
248         struct sk_buff *skb;
249
250         if (!np->recverr)
251                 return;
252
253         skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
254         if (!skb)
255                 return;
256
257         skb_put(skb, sizeof(struct ipv6hdr));
258         skb_reset_network_header(skb);
259         iph = ipv6_hdr(skb);
260         ipv6_addr_copy(&iph->daddr, &fl->fl6_dst);
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 = fl->fl_ip_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
280 /*
281  *      Handle MSG_ERRQUEUE
282  */
283 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len)
284 {
285         struct ipv6_pinfo *np = inet6_sk(sk);
286         struct sock_exterr_skb *serr;
287         struct sk_buff *skb, *skb2;
288         struct sockaddr_in6 *sin;
289         struct {
290                 struct sock_extended_err ee;
291                 struct sockaddr_in6      offender;
292         } errhdr;
293         int err;
294         int copied;
295
296         err = -EAGAIN;
297         skb = skb_dequeue(&sk->sk_error_queue);
298         if (skb == NULL)
299                 goto out;
300
301         copied = skb->len;
302         if (copied > len) {
303                 msg->msg_flags |= MSG_TRUNC;
304                 copied = len;
305         }
306         err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
307         if (err)
308                 goto out_free_skb;
309
310         sock_recv_timestamp(msg, sk, skb);
311
312         serr = SKB_EXT_ERR(skb);
313
314         sin = (struct sockaddr_in6 *)msg->msg_name;
315         if (sin) {
316                 const unsigned char *nh = skb_network_header(skb);
317                 sin->sin6_family = AF_INET6;
318                 sin->sin6_flowinfo = 0;
319                 sin->sin6_port = serr->port;
320                 sin->sin6_scope_id = 0;
321                 if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6) {
322                         ipv6_addr_copy(&sin->sin6_addr,
323                                   (struct in6_addr *)(nh + serr->addr_offset));
324                         if (np->sndflow)
325                                 sin->sin6_flowinfo =
326                                         (*(__be32 *)(nh + serr->addr_offset - 24) &
327                                          IPV6_FLOWINFO_MASK);
328                         if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
329                                 sin->sin6_scope_id = IP6CB(skb)->iif;
330                 } else {
331                         ipv6_addr_set(&sin->sin6_addr, 0, 0,
332                                       htonl(0xffff),
333                                       *(__be32 *)(nh + serr->addr_offset));
334                 }
335         }
336
337         memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
338         sin = &errhdr.offender;
339         sin->sin6_family = AF_UNSPEC;
340         if (serr->ee.ee_origin != SO_EE_ORIGIN_LOCAL) {
341                 sin->sin6_family = AF_INET6;
342                 sin->sin6_flowinfo = 0;
343                 sin->sin6_scope_id = 0;
344                 if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6) {
345                         ipv6_addr_copy(&sin->sin6_addr, &ipv6_hdr(skb)->saddr);
346                         if (np->rxopt.all)
347                                 datagram_recv_ctl(sk, msg, skb);
348                         if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
349                                 sin->sin6_scope_id = IP6CB(skb)->iif;
350                 } else {
351                         struct inet_sock *inet = inet_sk(sk);
352
353                         ipv6_addr_set(&sin->sin6_addr, 0, 0,
354                                       htonl(0xffff), ip_hdr(skb)->saddr);
355                         if (inet->cmsg_flags)
356                                 ip_cmsg_recv(msg, skb);
357                 }
358         }
359
360         put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr);
361
362         /* Now we could try to dump offended packet options */
363
364         msg->msg_flags |= MSG_ERRQUEUE;
365         err = copied;
366
367         /* Reset and regenerate socket error */
368         spin_lock_bh(&sk->sk_error_queue.lock);
369         sk->sk_err = 0;
370         if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
371                 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
372                 spin_unlock_bh(&sk->sk_error_queue.lock);
373                 sk->sk_error_report(sk);
374         } else {
375                 spin_unlock_bh(&sk->sk_error_queue.lock);
376         }
377
378 out_free_skb:
379         kfree_skb(skb);
380 out:
381         return err;
382 }
383
384
385
386 int datagram_recv_ctl(struct sock *sk, struct msghdr *msg, struct sk_buff *skb)
387 {
388         struct ipv6_pinfo *np = inet6_sk(sk);
389         struct inet6_skb_parm *opt = IP6CB(skb);
390         unsigned char *nh = skb_network_header(skb);
391
392         if (np->rxopt.bits.rxinfo) {
393                 struct in6_pktinfo src_info;
394
395                 src_info.ipi6_ifindex = opt->iif;
396                 ipv6_addr_copy(&src_info.ipi6_addr, &ipv6_hdr(skb)->daddr);
397                 put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
398         }
399
400         if (np->rxopt.bits.rxhlim) {
401                 int hlim = ipv6_hdr(skb)->hop_limit;
402                 put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
403         }
404
405         if (np->rxopt.bits.rxtclass) {
406                 int tclass = (ntohl(*(__be32 *)ipv6_hdr(skb)) >> 20) & 0xff;
407                 put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
408         }
409
410         if (np->rxopt.bits.rxflow && (*(__be32 *)nh & IPV6_FLOWINFO_MASK)) {
411                 __be32 flowinfo = *(__be32 *)nh & IPV6_FLOWINFO_MASK;
412                 put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
413         }
414
415         /* HbH is allowed only once */
416         if (np->rxopt.bits.hopopts && opt->hop) {
417                 u8 *ptr = nh + opt->hop;
418                 put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr);
419         }
420
421         if (opt->lastopt &&
422             (np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) {
423                 /*
424                  * Silly enough, but we need to reparse in order to
425                  * report extension headers (except for HbH)
426                  * in order.
427                  *
428                  * Also note that IPV6_RECVRTHDRDSTOPTS is NOT
429                  * (and WILL NOT be) defined because
430                  * IPV6_RECVDSTOPTS is more generic. --yoshfuji
431                  */
432                 unsigned int off = sizeof(struct ipv6hdr);
433                 u8 nexthdr = ipv6_hdr(skb)->nexthdr;
434
435                 while (off <= opt->lastopt) {
436                         unsigned len;
437                         u8 *ptr = nh + off;
438
439                         switch(nexthdr) {
440                         case IPPROTO_DSTOPTS:
441                                 nexthdr = ptr[0];
442                                 len = (ptr[1] + 1) << 3;
443                                 if (np->rxopt.bits.dstopts)
444                                         put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, ptr);
445                                 break;
446                         case IPPROTO_ROUTING:
447                                 nexthdr = ptr[0];
448                                 len = (ptr[1] + 1) << 3;
449                                 if (np->rxopt.bits.srcrt)
450                                         put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, ptr);
451                                 break;
452                         case IPPROTO_AH:
453                                 nexthdr = ptr[0];
454                                 len = (ptr[1] + 2) << 2;
455                                 break;
456                         default:
457                                 nexthdr = ptr[0];
458                                 len = (ptr[1] + 1) << 3;
459                                 break;
460                         }
461
462                         off += len;
463                 }
464         }
465
466         /* socket options in old style */
467         if (np->rxopt.bits.rxoinfo) {
468                 struct in6_pktinfo src_info;
469
470                 src_info.ipi6_ifindex = opt->iif;
471                 ipv6_addr_copy(&src_info.ipi6_addr, &ipv6_hdr(skb)->daddr);
472                 put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
473         }
474         if (np->rxopt.bits.rxohlim) {
475                 int hlim = ipv6_hdr(skb)->hop_limit;
476                 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
477         }
478         if (np->rxopt.bits.ohopopts && opt->hop) {
479                 u8 *ptr = nh + opt->hop;
480                 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, (ptr[1]+1)<<3, ptr);
481         }
482         if (np->rxopt.bits.odstopts && opt->dst0) {
483                 u8 *ptr = nh + opt->dst0;
484                 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
485         }
486         if (np->rxopt.bits.osrcrt && opt->srcrt) {
487                 struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt);
488                 put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, (rthdr->hdrlen+1) << 3, rthdr);
489         }
490         if (np->rxopt.bits.odstopts && opt->dst1) {
491                 u8 *ptr = nh + opt->dst1;
492                 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
493         }
494         return 0;
495 }
496
497 int datagram_send_ctl(struct net *net,
498                       struct msghdr *msg, struct flowi *fl,
499                       struct ipv6_txoptions *opt,
500                       int *hlimit, int *tclass)
501 {
502         struct in6_pktinfo *src_info;
503         struct cmsghdr *cmsg;
504         struct ipv6_rt_hdr *rthdr;
505         struct ipv6_opt_hdr *hdr;
506         int len;
507         int err = 0;
508
509         for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
510                 int addr_type;
511
512                 if (!CMSG_OK(msg, cmsg)) {
513                         err = -EINVAL;
514                         goto exit_f;
515                 }
516
517                 if (cmsg->cmsg_level != SOL_IPV6)
518                         continue;
519
520                 switch (cmsg->cmsg_type) {
521                 case IPV6_PKTINFO:
522                 case IPV6_2292PKTINFO:
523                     {
524                         struct net_device *dev = NULL;
525
526                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) {
527                                 err = -EINVAL;
528                                 goto exit_f;
529                         }
530
531                         src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
532
533                         if (src_info->ipi6_ifindex) {
534                                 if (fl->oif && src_info->ipi6_ifindex != fl->oif)
535                                         return -EINVAL;
536                                 fl->oif = src_info->ipi6_ifindex;
537                         }
538
539                         addr_type = __ipv6_addr_type(&src_info->ipi6_addr);
540
541                         if (fl->oif) {
542                                 dev = dev_get_by_index(net, fl->oif);
543                                 if (!dev)
544                                         return -ENODEV;
545                         } else if (addr_type & IPV6_ADDR_LINKLOCAL)
546                                 return -EINVAL;
547
548                         if (addr_type != IPV6_ADDR_ANY) {
549                                 int strict = __ipv6_addr_src_scope(addr_type) <= IPV6_ADDR_SCOPE_LINKLOCAL;
550                                 if (!ipv6_chk_addr(net, &src_info->ipi6_addr,
551                                                    strict ? dev : NULL, 0))
552                                         err = -EINVAL;
553                                 else
554                                         ipv6_addr_copy(&fl->fl6_src, &src_info->ipi6_addr);
555                         }
556
557                         if (dev)
558                                 dev_put(dev);
559
560                         if (err)
561                                 goto exit_f;
562
563                         break;
564                     }
565
566                 case IPV6_FLOWINFO:
567                         if (cmsg->cmsg_len < CMSG_LEN(4)) {
568                                 err = -EINVAL;
569                                 goto exit_f;
570                         }
571
572                         if (fl->fl6_flowlabel&IPV6_FLOWINFO_MASK) {
573                                 if ((fl->fl6_flowlabel^*(__be32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) {
574                                         err = -EINVAL;
575                                         goto exit_f;
576                                 }
577                         }
578                         fl->fl6_flowlabel = IPV6_FLOWINFO_MASK & *(__be32 *)CMSG_DATA(cmsg);
579                         break;
580
581                 case IPV6_2292HOPOPTS:
582                 case IPV6_HOPOPTS:
583                         if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
584                                 err = -EINVAL;
585                                 goto exit_f;
586                         }
587
588                         hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
589                         len = ((hdr->hdrlen + 1) << 3);
590                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
591                                 err = -EINVAL;
592                                 goto exit_f;
593                         }
594                         if (!capable(CAP_NET_RAW)) {
595                                 err = -EPERM;
596                                 goto exit_f;
597                         }
598                         opt->opt_nflen += len;
599                         opt->hopopt = hdr;
600                         break;
601
602                 case IPV6_2292DSTOPTS:
603                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
604                                 err = -EINVAL;
605                                 goto exit_f;
606                         }
607
608                         hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
609                         len = ((hdr->hdrlen + 1) << 3);
610                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
611                                 err = -EINVAL;
612                                 goto exit_f;
613                         }
614                         if (!capable(CAP_NET_RAW)) {
615                                 err = -EPERM;
616                                 goto exit_f;
617                         }
618                         if (opt->dst1opt) {
619                                 err = -EINVAL;
620                                 goto exit_f;
621                         }
622                         opt->opt_flen += len;
623                         opt->dst1opt = hdr;
624                         break;
625
626                 case IPV6_DSTOPTS:
627                 case IPV6_RTHDRDSTOPTS:
628                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
629                                 err = -EINVAL;
630                                 goto exit_f;
631                         }
632
633                         hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
634                         len = ((hdr->hdrlen + 1) << 3);
635                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
636                                 err = -EINVAL;
637                                 goto exit_f;
638                         }
639                         if (!capable(CAP_NET_RAW)) {
640                                 err = -EPERM;
641                                 goto exit_f;
642                         }
643                         if (cmsg->cmsg_type == IPV6_DSTOPTS) {
644                                 opt->opt_flen += len;
645                                 opt->dst1opt = hdr;
646                         } else {
647                                 opt->opt_nflen += len;
648                                 opt->dst0opt = hdr;
649                         }
650                         break;
651
652                 case IPV6_2292RTHDR:
653                 case IPV6_RTHDR:
654                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) {
655                                 err = -EINVAL;
656                                 goto exit_f;
657                         }
658
659                         rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg);
660
661                         switch (rthdr->type) {
662 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
663                         case IPV6_SRCRT_TYPE_2:
664                                 break;
665 #endif
666                         default:
667                                 err = -EINVAL;
668                                 goto exit_f;
669                         }
670
671                         len = ((rthdr->hdrlen + 1) << 3);
672
673                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
674                                 err = -EINVAL;
675                                 goto exit_f;
676                         }
677
678                         /* segments left must also match */
679                         if ((rthdr->hdrlen >> 1) != rthdr->segments_left) {
680                                 err = -EINVAL;
681                                 goto exit_f;
682                         }
683
684                         opt->opt_nflen += len;
685                         opt->srcrt = rthdr;
686
687                         if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) {
688                                 int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3);
689
690                                 opt->opt_nflen += dsthdrlen;
691                                 opt->dst0opt = opt->dst1opt;
692                                 opt->dst1opt = NULL;
693                                 opt->opt_flen -= dsthdrlen;
694                         }
695
696                         break;
697
698                 case IPV6_2292HOPLIMIT:
699                 case IPV6_HOPLIMIT:
700                         if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
701                                 err = -EINVAL;
702                                 goto exit_f;
703                         }
704
705                         *hlimit = *(int *)CMSG_DATA(cmsg);
706                         if (*hlimit < -1 || *hlimit > 0xff) {
707                                 err = -EINVAL;
708                                 goto exit_f;
709                         }
710
711                         break;
712
713                 case IPV6_TCLASS:
714                     {
715                         int tc;
716
717                         err = -EINVAL;
718                         if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
719                                 goto exit_f;
720                         }
721
722                         tc = *(int *)CMSG_DATA(cmsg);
723                         if (tc < -1 || tc > 0xff)
724                                 goto exit_f;
725
726                         err = 0;
727                         *tclass = tc;
728
729                         break;
730                     }
731                 default:
732                         LIMIT_NETDEBUG(KERN_DEBUG "invalid cmsg type: %d\n",
733                                        cmsg->cmsg_type);
734                         err = -EINVAL;
735                         break;
736                 }
737         }
738
739 exit_f:
740         return err;
741 }