Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6
[linux-2.6.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_v4mapped(inet->inet_daddr, &np->daddr);
102
103                 if (ipv6_addr_any(&np->saddr))
104                         ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr);
105
106                 if (ipv6_addr_any(&np->rcv_saddr))
107                         ipv6_addr_set_v4mapped(inet->inet_rcv_saddr,
108                                                &np->rcv_saddr);
109
110                 goto out;
111         }
112
113         if (addr_type&IPV6_ADDR_LINKLOCAL) {
114                 if (addr_len >= sizeof(struct sockaddr_in6) &&
115                     usin->sin6_scope_id) {
116                         if (sk->sk_bound_dev_if &&
117                             sk->sk_bound_dev_if != usin->sin6_scope_id) {
118                                 err = -EINVAL;
119                                 goto out;
120                         }
121                         sk->sk_bound_dev_if = usin->sin6_scope_id;
122                 }
123
124                 if (!sk->sk_bound_dev_if && (addr_type & IPV6_ADDR_MULTICAST))
125                         sk->sk_bound_dev_if = np->mcast_oif;
126
127                 /* Connect to link-local address requires an interface */
128                 if (!sk->sk_bound_dev_if) {
129                         err = -EINVAL;
130                         goto out;
131                 }
132         }
133
134         ipv6_addr_copy(&np->daddr, daddr);
135         np->flow_label = fl.fl6_flowlabel;
136
137         inet->inet_dport = usin->sin6_port;
138
139         /*
140          *      Check for a route to destination an obtain the
141          *      destination cache for it.
142          */
143
144         fl.proto = sk->sk_protocol;
145         ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
146         ipv6_addr_copy(&fl.fl6_src, &np->saddr);
147         fl.oif = sk->sk_bound_dev_if;
148         fl.mark = sk->sk_mark;
149         fl.fl_ip_dport = inet->inet_dport;
150         fl.fl_ip_sport = inet->inet_sport;
151
152         if (!fl.oif && (addr_type&IPV6_ADDR_MULTICAST))
153                 fl.oif = np->mcast_oif;
154
155         security_sk_classify_flow(sk, &fl);
156
157         if (flowlabel) {
158                 if (flowlabel->opt && flowlabel->opt->srcrt) {
159                         struct rt0_hdr *rt0 = (struct rt0_hdr *) flowlabel->opt->srcrt;
160                         ipv6_addr_copy(&final, &fl.fl6_dst);
161                         ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
162                         final_p = &final;
163                 }
164         } else if (np->opt && np->opt->srcrt) {
165                 struct rt0_hdr *rt0 = (struct rt0_hdr *)np->opt->srcrt;
166                 ipv6_addr_copy(&final, &fl.fl6_dst);
167                 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
168                 final_p = &final;
169         }
170
171         err = ip6_dst_lookup(sk, &dst, &fl);
172         if (err)
173                 goto out;
174         if (final_p)
175                 ipv6_addr_copy(&fl.fl6_dst, final_p);
176
177         err = __xfrm_lookup(sock_net(sk), &dst, &fl, sk, XFRM_LOOKUP_WAIT);
178         if (err < 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->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_v4mapped(*(__be32 *)(nh + serr->addr_offset),
332                                                &sin->sin6_addr);
333                 }
334         }
335
336         memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
337         sin = &errhdr.offender;
338         sin->sin6_family = AF_UNSPEC;
339         if (serr->ee.ee_origin != SO_EE_ORIGIN_LOCAL) {
340                 sin->sin6_family = AF_INET6;
341                 sin->sin6_flowinfo = 0;
342                 sin->sin6_scope_id = 0;
343                 if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6) {
344                         ipv6_addr_copy(&sin->sin6_addr, &ipv6_hdr(skb)->saddr);
345                         if (np->rxopt.all)
346                                 datagram_recv_ctl(sk, msg, skb);
347                         if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
348                                 sin->sin6_scope_id = IP6CB(skb)->iif;
349                 } else {
350                         struct inet_sock *inet = inet_sk(sk);
351
352                         ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
353                                                &sin->sin6_addr);
354                         if (inet->cmsg_flags)
355                                 ip_cmsg_recv(msg, skb);
356                 }
357         }
358
359         put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr);
360
361         /* Now we could try to dump offended packet options */
362
363         msg->msg_flags |= MSG_ERRQUEUE;
364         err = copied;
365
366         /* Reset and regenerate socket error */
367         spin_lock_bh(&sk->sk_error_queue.lock);
368         sk->sk_err = 0;
369         if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
370                 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
371                 spin_unlock_bh(&sk->sk_error_queue.lock);
372                 sk->sk_error_report(sk);
373         } else {
374                 spin_unlock_bh(&sk->sk_error_queue.lock);
375         }
376
377 out_free_skb:
378         kfree_skb(skb);
379 out:
380         return err;
381 }
382
383
384
385 int datagram_recv_ctl(struct sock *sk, struct msghdr *msg, struct sk_buff *skb)
386 {
387         struct ipv6_pinfo *np = inet6_sk(sk);
388         struct inet6_skb_parm *opt = IP6CB(skb);
389         unsigned char *nh = skb_network_header(skb);
390
391         if (np->rxopt.bits.rxinfo) {
392                 struct in6_pktinfo src_info;
393
394                 src_info.ipi6_ifindex = opt->iif;
395                 ipv6_addr_copy(&src_info.ipi6_addr, &ipv6_hdr(skb)->daddr);
396                 put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
397         }
398
399         if (np->rxopt.bits.rxhlim) {
400                 int hlim = ipv6_hdr(skb)->hop_limit;
401                 put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
402         }
403
404         if (np->rxopt.bits.rxtclass) {
405                 int tclass = (ntohl(*(__be32 *)ipv6_hdr(skb)) >> 20) & 0xff;
406                 put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
407         }
408
409         if (np->rxopt.bits.rxflow && (*(__be32 *)nh & IPV6_FLOWINFO_MASK)) {
410                 __be32 flowinfo = *(__be32 *)nh & IPV6_FLOWINFO_MASK;
411                 put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
412         }
413
414         /* HbH is allowed only once */
415         if (np->rxopt.bits.hopopts && opt->hop) {
416                 u8 *ptr = nh + opt->hop;
417                 put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr);
418         }
419
420         if (opt->lastopt &&
421             (np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) {
422                 /*
423                  * Silly enough, but we need to reparse in order to
424                  * report extension headers (except for HbH)
425                  * in order.
426                  *
427                  * Also note that IPV6_RECVRTHDRDSTOPTS is NOT
428                  * (and WILL NOT be) defined because
429                  * IPV6_RECVDSTOPTS is more generic. --yoshfuji
430                  */
431                 unsigned int off = sizeof(struct ipv6hdr);
432                 u8 nexthdr = ipv6_hdr(skb)->nexthdr;
433
434                 while (off <= opt->lastopt) {
435                         unsigned len;
436                         u8 *ptr = nh + off;
437
438                         switch(nexthdr) {
439                         case IPPROTO_DSTOPTS:
440                                 nexthdr = ptr[0];
441                                 len = (ptr[1] + 1) << 3;
442                                 if (np->rxopt.bits.dstopts)
443                                         put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, ptr);
444                                 break;
445                         case IPPROTO_ROUTING:
446                                 nexthdr = ptr[0];
447                                 len = (ptr[1] + 1) << 3;
448                                 if (np->rxopt.bits.srcrt)
449                                         put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, ptr);
450                                 break;
451                         case IPPROTO_AH:
452                                 nexthdr = ptr[0];
453                                 len = (ptr[1] + 2) << 2;
454                                 break;
455                         default:
456                                 nexthdr = ptr[0];
457                                 len = (ptr[1] + 1) << 3;
458                                 break;
459                         }
460
461                         off += len;
462                 }
463         }
464
465         /* socket options in old style */
466         if (np->rxopt.bits.rxoinfo) {
467                 struct in6_pktinfo src_info;
468
469                 src_info.ipi6_ifindex = opt->iif;
470                 ipv6_addr_copy(&src_info.ipi6_addr, &ipv6_hdr(skb)->daddr);
471                 put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
472         }
473         if (np->rxopt.bits.rxohlim) {
474                 int hlim = ipv6_hdr(skb)->hop_limit;
475                 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
476         }
477         if (np->rxopt.bits.ohopopts && opt->hop) {
478                 u8 *ptr = nh + opt->hop;
479                 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, (ptr[1]+1)<<3, ptr);
480         }
481         if (np->rxopt.bits.odstopts && opt->dst0) {
482                 u8 *ptr = nh + opt->dst0;
483                 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
484         }
485         if (np->rxopt.bits.osrcrt && opt->srcrt) {
486                 struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt);
487                 put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, (rthdr->hdrlen+1) << 3, rthdr);
488         }
489         if (np->rxopt.bits.odstopts && opt->dst1) {
490                 u8 *ptr = nh + opt->dst1;
491                 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
492         }
493         return 0;
494 }
495
496 int datagram_send_ctl(struct net *net,
497                       struct msghdr *msg, struct flowi *fl,
498                       struct ipv6_txoptions *opt,
499                       int *hlimit, int *tclass)
500 {
501         struct in6_pktinfo *src_info;
502         struct cmsghdr *cmsg;
503         struct ipv6_rt_hdr *rthdr;
504         struct ipv6_opt_hdr *hdr;
505         int len;
506         int err = 0;
507
508         for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
509                 int addr_type;
510
511                 if (!CMSG_OK(msg, cmsg)) {
512                         err = -EINVAL;
513                         goto exit_f;
514                 }
515
516                 if (cmsg->cmsg_level != SOL_IPV6)
517                         continue;
518
519                 switch (cmsg->cmsg_type) {
520                 case IPV6_PKTINFO:
521                 case IPV6_2292PKTINFO:
522                     {
523                         struct net_device *dev = NULL;
524
525                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) {
526                                 err = -EINVAL;
527                                 goto exit_f;
528                         }
529
530                         src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
531
532                         if (src_info->ipi6_ifindex) {
533                                 if (fl->oif && src_info->ipi6_ifindex != fl->oif)
534                                         return -EINVAL;
535                                 fl->oif = src_info->ipi6_ifindex;
536                         }
537
538                         addr_type = __ipv6_addr_type(&src_info->ipi6_addr);
539
540                         rcu_read_lock();
541                         if (fl->oif) {
542                                 dev = dev_get_by_index_rcu(net, fl->oif);
543                                 if (!dev) {
544                                         rcu_read_unlock();
545                                         return -ENODEV;
546                                 }
547                         } else if (addr_type & IPV6_ADDR_LINKLOCAL) {
548                                 rcu_read_unlock();
549                                 return -EINVAL;
550                         }
551
552                         if (addr_type != IPV6_ADDR_ANY) {
553                                 int strict = __ipv6_addr_src_scope(addr_type) <= IPV6_ADDR_SCOPE_LINKLOCAL;
554                                 if (!ipv6_chk_addr(net, &src_info->ipi6_addr,
555                                                    strict ? dev : NULL, 0))
556                                         err = -EINVAL;
557                                 else
558                                         ipv6_addr_copy(&fl->fl6_src, &src_info->ipi6_addr);
559                         }
560
561                         rcu_read_unlock();
562
563                         if (err)
564                                 goto exit_f;
565
566                         break;
567                     }
568
569                 case IPV6_FLOWINFO:
570                         if (cmsg->cmsg_len < CMSG_LEN(4)) {
571                                 err = -EINVAL;
572                                 goto exit_f;
573                         }
574
575                         if (fl->fl6_flowlabel&IPV6_FLOWINFO_MASK) {
576                                 if ((fl->fl6_flowlabel^*(__be32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) {
577                                         err = -EINVAL;
578                                         goto exit_f;
579                                 }
580                         }
581                         fl->fl6_flowlabel = IPV6_FLOWINFO_MASK & *(__be32 *)CMSG_DATA(cmsg);
582                         break;
583
584                 case IPV6_2292HOPOPTS:
585                 case IPV6_HOPOPTS:
586                         if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
587                                 err = -EINVAL;
588                                 goto exit_f;
589                         }
590
591                         hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
592                         len = ((hdr->hdrlen + 1) << 3);
593                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
594                                 err = -EINVAL;
595                                 goto exit_f;
596                         }
597                         if (!capable(CAP_NET_RAW)) {
598                                 err = -EPERM;
599                                 goto exit_f;
600                         }
601                         opt->opt_nflen += len;
602                         opt->hopopt = hdr;
603                         break;
604
605                 case IPV6_2292DSTOPTS:
606                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
607                                 err = -EINVAL;
608                                 goto exit_f;
609                         }
610
611                         hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
612                         len = ((hdr->hdrlen + 1) << 3);
613                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
614                                 err = -EINVAL;
615                                 goto exit_f;
616                         }
617                         if (!capable(CAP_NET_RAW)) {
618                                 err = -EPERM;
619                                 goto exit_f;
620                         }
621                         if (opt->dst1opt) {
622                                 err = -EINVAL;
623                                 goto exit_f;
624                         }
625                         opt->opt_flen += len;
626                         opt->dst1opt = hdr;
627                         break;
628
629                 case IPV6_DSTOPTS:
630                 case IPV6_RTHDRDSTOPTS:
631                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
632                                 err = -EINVAL;
633                                 goto exit_f;
634                         }
635
636                         hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
637                         len = ((hdr->hdrlen + 1) << 3);
638                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
639                                 err = -EINVAL;
640                                 goto exit_f;
641                         }
642                         if (!capable(CAP_NET_RAW)) {
643                                 err = -EPERM;
644                                 goto exit_f;
645                         }
646                         if (cmsg->cmsg_type == IPV6_DSTOPTS) {
647                                 opt->opt_flen += len;
648                                 opt->dst1opt = hdr;
649                         } else {
650                                 opt->opt_nflen += len;
651                                 opt->dst0opt = hdr;
652                         }
653                         break;
654
655                 case IPV6_2292RTHDR:
656                 case IPV6_RTHDR:
657                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) {
658                                 err = -EINVAL;
659                                 goto exit_f;
660                         }
661
662                         rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg);
663
664                         switch (rthdr->type) {
665 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
666                         case IPV6_SRCRT_TYPE_2:
667                                 if (rthdr->hdrlen != 2 ||
668                                     rthdr->segments_left != 1) {
669                                         err = -EINVAL;
670                                         goto exit_f;
671                                 }
672                                 break;
673 #endif
674                         default:
675                                 err = -EINVAL;
676                                 goto exit_f;
677                         }
678
679                         len = ((rthdr->hdrlen + 1) << 3);
680
681                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
682                                 err = -EINVAL;
683                                 goto exit_f;
684                         }
685
686                         /* segments left must also match */
687                         if ((rthdr->hdrlen >> 1) != rthdr->segments_left) {
688                                 err = -EINVAL;
689                                 goto exit_f;
690                         }
691
692                         opt->opt_nflen += len;
693                         opt->srcrt = rthdr;
694
695                         if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) {
696                                 int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3);
697
698                                 opt->opt_nflen += dsthdrlen;
699                                 opt->dst0opt = opt->dst1opt;
700                                 opt->dst1opt = NULL;
701                                 opt->opt_flen -= dsthdrlen;
702                         }
703
704                         break;
705
706                 case IPV6_2292HOPLIMIT:
707                 case IPV6_HOPLIMIT:
708                         if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
709                                 err = -EINVAL;
710                                 goto exit_f;
711                         }
712
713                         *hlimit = *(int *)CMSG_DATA(cmsg);
714                         if (*hlimit < -1 || *hlimit > 0xff) {
715                                 err = -EINVAL;
716                                 goto exit_f;
717                         }
718
719                         break;
720
721                 case IPV6_TCLASS:
722                     {
723                         int tc;
724
725                         err = -EINVAL;
726                         if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
727                                 goto exit_f;
728                         }
729
730                         tc = *(int *)CMSG_DATA(cmsg);
731                         if (tc < -1 || tc > 0xff)
732                                 goto exit_f;
733
734                         err = 0;
735                         *tclass = tc;
736
737                         break;
738                     }
739                 default:
740                         LIMIT_NETDEBUG(KERN_DEBUG "invalid cmsg type: %d\n",
741                                        cmsg->cmsg_type);
742                         err = -EINVAL;
743                         goto exit_f;
744                 }
745         }
746
747 exit_f:
748         return err;
749 }