Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux-2.6] / 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         err = __xfrm_lookup(sock_net(sk), &dst, &fl, sk, XFRM_LOOKUP_WAIT);
179         if (err < 0) {
180                 if (err == -EREMOTE)
181                         err = ip6_dst_blackhole(sk, &dst, &fl);
182                 if (err < 0)
183                         goto out;
184         }
185
186         /* source address lookup done in ip6_dst_lookup */
187
188         if (ipv6_addr_any(&np->saddr))
189                 ipv6_addr_copy(&np->saddr, &fl.fl6_src);
190
191         if (ipv6_addr_any(&np->rcv_saddr)) {
192                 ipv6_addr_copy(&np->rcv_saddr, &fl.fl6_src);
193                 inet->rcv_saddr = LOOPBACK4_IPV6;
194         }
195
196         ip6_dst_store(sk, dst,
197                       ipv6_addr_equal(&fl.fl6_dst, &np->daddr) ?
198                       &np->daddr : NULL,
199 #ifdef CONFIG_IPV6_SUBTREES
200                       ipv6_addr_equal(&fl.fl6_src, &np->saddr) ?
201                       &np->saddr :
202 #endif
203                       NULL);
204
205         sk->sk_state = TCP_ESTABLISHED;
206 out:
207         fl6_sock_release(flowlabel);
208         return err;
209 }
210
211 void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
212                      __be16 port, u32 info, u8 *payload)
213 {
214         struct ipv6_pinfo *np  = inet6_sk(sk);
215         struct icmp6hdr *icmph = icmp6_hdr(skb);
216         struct sock_exterr_skb *serr;
217
218         if (!np->recverr)
219                 return;
220
221         skb = skb_clone(skb, GFP_ATOMIC);
222         if (!skb)
223                 return;
224
225         serr = SKB_EXT_ERR(skb);
226         serr->ee.ee_errno = err;
227         serr->ee.ee_origin = SO_EE_ORIGIN_ICMP6;
228         serr->ee.ee_type = icmph->icmp6_type;
229         serr->ee.ee_code = icmph->icmp6_code;
230         serr->ee.ee_pad = 0;
231         serr->ee.ee_info = info;
232         serr->ee.ee_data = 0;
233         serr->addr_offset = (u8 *)&(((struct ipv6hdr *)(icmph + 1))->daddr) -
234                                   skb_network_header(skb);
235         serr->port = port;
236
237         __skb_pull(skb, payload - skb->data);
238         skb_reset_transport_header(skb);
239
240         if (sock_queue_err_skb(sk, skb))
241                 kfree_skb(skb);
242 }
243
244 void ipv6_local_error(struct sock *sk, int err, struct flowi *fl, u32 info)
245 {
246         struct ipv6_pinfo *np = inet6_sk(sk);
247         struct sock_exterr_skb *serr;
248         struct ipv6hdr *iph;
249         struct sk_buff *skb;
250
251         if (!np->recverr)
252                 return;
253
254         skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
255         if (!skb)
256                 return;
257
258         skb_put(skb, sizeof(struct ipv6hdr));
259         skb_reset_network_header(skb);
260         iph = ipv6_hdr(skb);
261         ipv6_addr_copy(&iph->daddr, &fl->fl6_dst);
262
263         serr = SKB_EXT_ERR(skb);
264         serr->ee.ee_errno = err;
265         serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
266         serr->ee.ee_type = 0;
267         serr->ee.ee_code = 0;
268         serr->ee.ee_pad = 0;
269         serr->ee.ee_info = info;
270         serr->ee.ee_data = 0;
271         serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
272         serr->port = fl->fl_ip_dport;
273
274         __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
275         skb_reset_transport_header(skb);
276
277         if (sock_queue_err_skb(sk, skb))
278                 kfree_skb(skb);
279 }
280
281 /*
282  *      Handle MSG_ERRQUEUE
283  */
284 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len)
285 {
286         struct ipv6_pinfo *np = inet6_sk(sk);
287         struct sock_exterr_skb *serr;
288         struct sk_buff *skb, *skb2;
289         struct sockaddr_in6 *sin;
290         struct {
291                 struct sock_extended_err ee;
292                 struct sockaddr_in6      offender;
293         } errhdr;
294         int err;
295         int copied;
296
297         err = -EAGAIN;
298         skb = skb_dequeue(&sk->sk_error_queue);
299         if (skb == NULL)
300                 goto out;
301
302         copied = skb->len;
303         if (copied > len) {
304                 msg->msg_flags |= MSG_TRUNC;
305                 copied = len;
306         }
307         err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
308         if (err)
309                 goto out_free_skb;
310
311         sock_recv_timestamp(msg, sk, skb);
312
313         serr = SKB_EXT_ERR(skb);
314
315         sin = (struct sockaddr_in6 *)msg->msg_name;
316         if (sin) {
317                 const unsigned char *nh = skb_network_header(skb);
318                 sin->sin6_family = AF_INET6;
319                 sin->sin6_flowinfo = 0;
320                 sin->sin6_port = serr->port;
321                 sin->sin6_scope_id = 0;
322                 if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6) {
323                         ipv6_addr_copy(&sin->sin6_addr,
324                                   (struct in6_addr *)(nh + serr->addr_offset));
325                         if (np->sndflow)
326                                 sin->sin6_flowinfo =
327                                         (*(__be32 *)(nh + serr->addr_offset - 24) &
328                                          IPV6_FLOWINFO_MASK);
329                         if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
330                                 sin->sin6_scope_id = IP6CB(skb)->iif;
331                 } else {
332                         ipv6_addr_set(&sin->sin6_addr, 0, 0,
333                                       htonl(0xffff),
334                                       *(__be32 *)(nh + serr->addr_offset));
335                 }
336         }
337
338         memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
339         sin = &errhdr.offender;
340         sin->sin6_family = AF_UNSPEC;
341         if (serr->ee.ee_origin != SO_EE_ORIGIN_LOCAL) {
342                 sin->sin6_family = AF_INET6;
343                 sin->sin6_flowinfo = 0;
344                 sin->sin6_scope_id = 0;
345                 if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6) {
346                         ipv6_addr_copy(&sin->sin6_addr, &ipv6_hdr(skb)->saddr);
347                         if (np->rxopt.all)
348                                 datagram_recv_ctl(sk, msg, skb);
349                         if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
350                                 sin->sin6_scope_id = IP6CB(skb)->iif;
351                 } else {
352                         struct inet_sock *inet = inet_sk(sk);
353
354                         ipv6_addr_set(&sin->sin6_addr, 0, 0,
355                                       htonl(0xffff), ip_hdr(skb)->saddr);
356                         if (inet->cmsg_flags)
357                                 ip_cmsg_recv(msg, skb);
358                 }
359         }
360
361         put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr);
362
363         /* Now we could try to dump offended packet options */
364
365         msg->msg_flags |= MSG_ERRQUEUE;
366         err = copied;
367
368         /* Reset and regenerate socket error */
369         spin_lock_bh(&sk->sk_error_queue.lock);
370         sk->sk_err = 0;
371         if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
372                 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
373                 spin_unlock_bh(&sk->sk_error_queue.lock);
374                 sk->sk_error_report(sk);
375         } else {
376                 spin_unlock_bh(&sk->sk_error_queue.lock);
377         }
378
379 out_free_skb:
380         kfree_skb(skb);
381 out:
382         return err;
383 }
384
385
386
387 int datagram_recv_ctl(struct sock *sk, struct msghdr *msg, struct sk_buff *skb)
388 {
389         struct ipv6_pinfo *np = inet6_sk(sk);
390         struct inet6_skb_parm *opt = IP6CB(skb);
391         unsigned char *nh = skb_network_header(skb);
392
393         if (np->rxopt.bits.rxinfo) {
394                 struct in6_pktinfo src_info;
395
396                 src_info.ipi6_ifindex = opt->iif;
397                 ipv6_addr_copy(&src_info.ipi6_addr, &ipv6_hdr(skb)->daddr);
398                 put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
399         }
400
401         if (np->rxopt.bits.rxhlim) {
402                 int hlim = ipv6_hdr(skb)->hop_limit;
403                 put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
404         }
405
406         if (np->rxopt.bits.rxtclass) {
407                 int tclass = (ntohl(*(__be32 *)ipv6_hdr(skb)) >> 20) & 0xff;
408                 put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
409         }
410
411         if (np->rxopt.bits.rxflow && (*(__be32 *)nh & IPV6_FLOWINFO_MASK)) {
412                 __be32 flowinfo = *(__be32 *)nh & IPV6_FLOWINFO_MASK;
413                 put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
414         }
415
416         /* HbH is allowed only once */
417         if (np->rxopt.bits.hopopts && opt->hop) {
418                 u8 *ptr = nh + opt->hop;
419                 put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr);
420         }
421
422         if (opt->lastopt &&
423             (np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) {
424                 /*
425                  * Silly enough, but we need to reparse in order to
426                  * report extension headers (except for HbH)
427                  * in order.
428                  *
429                  * Also note that IPV6_RECVRTHDRDSTOPTS is NOT
430                  * (and WILL NOT be) defined because
431                  * IPV6_RECVDSTOPTS is more generic. --yoshfuji
432                  */
433                 unsigned int off = sizeof(struct ipv6hdr);
434                 u8 nexthdr = ipv6_hdr(skb)->nexthdr;
435
436                 while (off <= opt->lastopt) {
437                         unsigned len;
438                         u8 *ptr = nh + off;
439
440                         switch(nexthdr) {
441                         case IPPROTO_DSTOPTS:
442                                 nexthdr = ptr[0];
443                                 len = (ptr[1] + 1) << 3;
444                                 if (np->rxopt.bits.dstopts)
445                                         put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, ptr);
446                                 break;
447                         case IPPROTO_ROUTING:
448                                 nexthdr = ptr[0];
449                                 len = (ptr[1] + 1) << 3;
450                                 if (np->rxopt.bits.srcrt)
451                                         put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, ptr);
452                                 break;
453                         case IPPROTO_AH:
454                                 nexthdr = ptr[0];
455                                 len = (ptr[1] + 2) << 2;
456                                 break;
457                         default:
458                                 nexthdr = ptr[0];
459                                 len = (ptr[1] + 1) << 3;
460                                 break;
461                         }
462
463                         off += len;
464                 }
465         }
466
467         /* socket options in old style */
468         if (np->rxopt.bits.rxoinfo) {
469                 struct in6_pktinfo src_info;
470
471                 src_info.ipi6_ifindex = opt->iif;
472                 ipv6_addr_copy(&src_info.ipi6_addr, &ipv6_hdr(skb)->daddr);
473                 put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
474         }
475         if (np->rxopt.bits.rxohlim) {
476                 int hlim = ipv6_hdr(skb)->hop_limit;
477                 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
478         }
479         if (np->rxopt.bits.ohopopts && opt->hop) {
480                 u8 *ptr = nh + opt->hop;
481                 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, (ptr[1]+1)<<3, ptr);
482         }
483         if (np->rxopt.bits.odstopts && opt->dst0) {
484                 u8 *ptr = nh + opt->dst0;
485                 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
486         }
487         if (np->rxopt.bits.osrcrt && opt->srcrt) {
488                 struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt);
489                 put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, (rthdr->hdrlen+1) << 3, rthdr);
490         }
491         if (np->rxopt.bits.odstopts && opt->dst1) {
492                 u8 *ptr = nh + opt->dst1;
493                 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
494         }
495         return 0;
496 }
497
498 int datagram_send_ctl(struct net *net,
499                       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(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(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                                 if (rthdr->hdrlen != 2 ||
666                                     rthdr->segments_left != 1) {
667                                         err = -EINVAL;
668                                         goto exit_f;
669                                 }
670                                 break;
671 #endif
672                         default:
673                                 err = -EINVAL;
674                                 goto exit_f;
675                         }
676
677                         len = ((rthdr->hdrlen + 1) << 3);
678
679                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
680                                 err = -EINVAL;
681                                 goto exit_f;
682                         }
683
684                         /* segments left must also match */
685                         if ((rthdr->hdrlen >> 1) != rthdr->segments_left) {
686                                 err = -EINVAL;
687                                 goto exit_f;
688                         }
689
690                         opt->opt_nflen += len;
691                         opt->srcrt = rthdr;
692
693                         if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) {
694                                 int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3);
695
696                                 opt->opt_nflen += dsthdrlen;
697                                 opt->dst0opt = opt->dst1opt;
698                                 opt->dst1opt = NULL;
699                                 opt->opt_flen -= dsthdrlen;
700                         }
701
702                         break;
703
704                 case IPV6_2292HOPLIMIT:
705                 case IPV6_HOPLIMIT:
706                         if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
707                                 err = -EINVAL;
708                                 goto exit_f;
709                         }
710
711                         *hlimit = *(int *)CMSG_DATA(cmsg);
712                         if (*hlimit < -1 || *hlimit > 0xff) {
713                                 err = -EINVAL;
714                                 goto exit_f;
715                         }
716
717                         break;
718
719                 case IPV6_TCLASS:
720                     {
721                         int tc;
722
723                         err = -EINVAL;
724                         if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
725                                 goto exit_f;
726                         }
727
728                         tc = *(int *)CMSG_DATA(cmsg);
729                         if (tc < -1 || tc > 0xff)
730                                 goto exit_f;
731
732                         err = 0;
733                         *tclass = tc;
734
735                         break;
736                     }
737                 default:
738                         LIMIT_NETDEBUG(KERN_DEBUG "invalid cmsg type: %d\n",
739                                        cmsg->cmsg_type);
740                         err = -EINVAL;
741                         goto exit_f;
742                 }
743         }
744
745 exit_f:
746         return err;
747 }