net: remove ipv6_addr_copy()
[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 #include <linux/slab.h>
25
26 #include <net/ipv6.h>
27 #include <net/ndisc.h>
28 #include <net/addrconf.h>
29 #include <net/transp_v6.h>
30 #include <net/ip6_route.h>
31 #include <net/tcp_states.h>
32
33 #include <linux/errqueue.h>
34 #include <asm/uaccess.h>
35
36 static inline int ipv6_mapped_addr_any(const struct in6_addr *a)
37 {
38         return (ipv6_addr_v4mapped(a) && (a->s6_addr32[3] == 0));
39 }
40
41 int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
42 {
43         struct sockaddr_in6     *usin = (struct sockaddr_in6 *) uaddr;
44         struct inet_sock        *inet = inet_sk(sk);
45         struct ipv6_pinfo       *np = inet6_sk(sk);
46         struct in6_addr         *daddr, *final_p, final;
47         struct dst_entry        *dst;
48         struct flowi6           fl6;
49         struct ip6_flowlabel    *flowlabel = NULL;
50         struct ipv6_txoptions   *opt;
51         int                     addr_type;
52         int                     err;
53
54         if (usin->sin6_family == AF_INET) {
55                 if (__ipv6_only_sock(sk))
56                         return -EAFNOSUPPORT;
57                 err = ip4_datagram_connect(sk, uaddr, addr_len);
58                 goto ipv4_connected;
59         }
60
61         if (addr_len < SIN6_LEN_RFC2133)
62                 return -EINVAL;
63
64         if (usin->sin6_family != AF_INET6)
65                 return -EAFNOSUPPORT;
66
67         memset(&fl6, 0, sizeof(fl6));
68         if (np->sndflow) {
69                 fl6.flowlabel = usin->sin6_flowinfo&IPV6_FLOWINFO_MASK;
70                 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
71                         flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
72                         if (flowlabel == NULL)
73                                 return -EINVAL;
74                         usin->sin6_addr = flowlabel->dst;
75                 }
76         }
77
78         addr_type = ipv6_addr_type(&usin->sin6_addr);
79
80         if (addr_type == IPV6_ADDR_ANY) {
81                 /*
82                  *      connect to self
83                  */
84                 usin->sin6_addr.s6_addr[15] = 0x01;
85         }
86
87         daddr = &usin->sin6_addr;
88
89         if (addr_type == IPV6_ADDR_MAPPED) {
90                 struct sockaddr_in sin;
91
92                 if (__ipv6_only_sock(sk)) {
93                         err = -ENETUNREACH;
94                         goto out;
95                 }
96                 sin.sin_family = AF_INET;
97                 sin.sin_addr.s_addr = daddr->s6_addr32[3];
98                 sin.sin_port = usin->sin6_port;
99
100                 err = ip4_datagram_connect(sk,
101                                            (struct sockaddr*) &sin,
102                                            sizeof(sin));
103
104 ipv4_connected:
105                 if (err)
106                         goto out;
107
108                 ipv6_addr_set_v4mapped(inet->inet_daddr, &np->daddr);
109
110                 if (ipv6_addr_any(&np->saddr) ||
111                     ipv6_mapped_addr_any(&np->saddr))
112                         ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr);
113
114                 if (ipv6_addr_any(&np->rcv_saddr) ||
115                     ipv6_mapped_addr_any(&np->rcv_saddr)) {
116                         ipv6_addr_set_v4mapped(inet->inet_rcv_saddr,
117                                                &np->rcv_saddr);
118                         if (sk->sk_prot->rehash)
119                                 sk->sk_prot->rehash(sk);
120                 }
121
122                 goto out;
123         }
124
125         if (addr_type&IPV6_ADDR_LINKLOCAL) {
126                 if (addr_len >= sizeof(struct sockaddr_in6) &&
127                     usin->sin6_scope_id) {
128                         if (sk->sk_bound_dev_if &&
129                             sk->sk_bound_dev_if != usin->sin6_scope_id) {
130                                 err = -EINVAL;
131                                 goto out;
132                         }
133                         sk->sk_bound_dev_if = usin->sin6_scope_id;
134                 }
135
136                 if (!sk->sk_bound_dev_if && (addr_type & IPV6_ADDR_MULTICAST))
137                         sk->sk_bound_dev_if = np->mcast_oif;
138
139                 /* Connect to link-local address requires an interface */
140                 if (!sk->sk_bound_dev_if) {
141                         err = -EINVAL;
142                         goto out;
143                 }
144         }
145
146         np->daddr = *daddr;
147         np->flow_label = fl6.flowlabel;
148
149         inet->inet_dport = usin->sin6_port;
150
151         /*
152          *      Check for a route to destination an obtain the
153          *      destination cache for it.
154          */
155
156         fl6.flowi6_proto = sk->sk_protocol;
157         fl6.daddr = np->daddr;
158         fl6.saddr = np->saddr;
159         fl6.flowi6_oif = sk->sk_bound_dev_if;
160         fl6.flowi6_mark = sk->sk_mark;
161         fl6.fl6_dport = inet->inet_dport;
162         fl6.fl6_sport = inet->inet_sport;
163
164         if (!fl6.flowi6_oif && (addr_type&IPV6_ADDR_MULTICAST))
165                 fl6.flowi6_oif = np->mcast_oif;
166
167         security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
168
169         opt = flowlabel ? flowlabel->opt : np->opt;
170         final_p = fl6_update_dst(&fl6, opt, &final);
171
172         dst = ip6_dst_lookup_flow(sk, &fl6, final_p, true);
173         err = 0;
174         if (IS_ERR(dst)) {
175                 err = PTR_ERR(dst);
176                 goto out;
177         }
178
179         /* source address lookup done in ip6_dst_lookup */
180
181         if (ipv6_addr_any(&np->saddr))
182                 np->saddr = fl6.saddr;
183
184         if (ipv6_addr_any(&np->rcv_saddr)) {
185                 np->rcv_saddr = fl6.saddr;
186                 inet->inet_rcv_saddr = LOOPBACK4_IPV6;
187                 if (sk->sk_prot->rehash)
188                         sk->sk_prot->rehash(sk);
189         }
190
191         ip6_dst_store(sk, dst,
192                       ipv6_addr_equal(&fl6.daddr, &np->daddr) ?
193                       &np->daddr : NULL,
194 #ifdef CONFIG_IPV6_SUBTREES
195                       ipv6_addr_equal(&fl6.saddr, &np->saddr) ?
196                       &np->saddr :
197 #endif
198                       NULL);
199
200         sk->sk_state = TCP_ESTABLISHED;
201 out:
202         fl6_sock_release(flowlabel);
203         return err;
204 }
205
206 void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
207                      __be16 port, u32 info, u8 *payload)
208 {
209         struct ipv6_pinfo *np  = inet6_sk(sk);
210         struct icmp6hdr *icmph = icmp6_hdr(skb);
211         struct sock_exterr_skb *serr;
212
213         if (!np->recverr)
214                 return;
215
216         skb = skb_clone(skb, GFP_ATOMIC);
217         if (!skb)
218                 return;
219
220         skb->protocol = htons(ETH_P_IPV6);
221
222         serr = SKB_EXT_ERR(skb);
223         serr->ee.ee_errno = err;
224         serr->ee.ee_origin = SO_EE_ORIGIN_ICMP6;
225         serr->ee.ee_type = icmph->icmp6_type;
226         serr->ee.ee_code = icmph->icmp6_code;
227         serr->ee.ee_pad = 0;
228         serr->ee.ee_info = info;
229         serr->ee.ee_data = 0;
230         serr->addr_offset = (u8 *)&(((struct ipv6hdr *)(icmph + 1))->daddr) -
231                                   skb_network_header(skb);
232         serr->port = port;
233
234         __skb_pull(skb, payload - skb->data);
235         skb_reset_transport_header(skb);
236
237         if (sock_queue_err_skb(sk, skb))
238                 kfree_skb(skb);
239 }
240
241 void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info)
242 {
243         struct ipv6_pinfo *np = inet6_sk(sk);
244         struct sock_exterr_skb *serr;
245         struct ipv6hdr *iph;
246         struct sk_buff *skb;
247
248         if (!np->recverr)
249                 return;
250
251         skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
252         if (!skb)
253                 return;
254
255         skb->protocol = htons(ETH_P_IPV6);
256
257         skb_put(skb, sizeof(struct ipv6hdr));
258         skb_reset_network_header(skb);
259         iph = ipv6_hdr(skb);
260         iph->daddr = fl6->daddr;
261
262         serr = SKB_EXT_ERR(skb);
263         serr->ee.ee_errno = err;
264         serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
265         serr->ee.ee_type = 0;
266         serr->ee.ee_code = 0;
267         serr->ee.ee_pad = 0;
268         serr->ee.ee_info = info;
269         serr->ee.ee_data = 0;
270         serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
271         serr->port = fl6->fl6_dport;
272
273         __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
274         skb_reset_transport_header(skb);
275
276         if (sock_queue_err_skb(sk, skb))
277                 kfree_skb(skb);
278 }
279
280 void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu)
281 {
282         struct ipv6_pinfo *np = inet6_sk(sk);
283         struct ipv6hdr *iph;
284         struct sk_buff *skb;
285         struct ip6_mtuinfo *mtu_info;
286
287         if (!np->rxopt.bits.rxpmtu)
288                 return;
289
290         skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
291         if (!skb)
292                 return;
293
294         skb_put(skb, sizeof(struct ipv6hdr));
295         skb_reset_network_header(skb);
296         iph = ipv6_hdr(skb);
297         iph->daddr = fl6->daddr;
298
299         mtu_info = IP6CBMTU(skb);
300
301         mtu_info->ip6m_mtu = mtu;
302         mtu_info->ip6m_addr.sin6_family = AF_INET6;
303         mtu_info->ip6m_addr.sin6_port = 0;
304         mtu_info->ip6m_addr.sin6_flowinfo = 0;
305         mtu_info->ip6m_addr.sin6_scope_id = fl6->flowi6_oif;
306         mtu_info->ip6m_addr.sin6_addr = ipv6_hdr(skb)->daddr;
307
308         __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
309         skb_reset_transport_header(skb);
310
311         skb = xchg(&np->rxpmtu, skb);
312         kfree_skb(skb);
313 }
314
315 /*
316  *      Handle MSG_ERRQUEUE
317  */
318 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len)
319 {
320         struct ipv6_pinfo *np = inet6_sk(sk);
321         struct sock_exterr_skb *serr;
322         struct sk_buff *skb, *skb2;
323         struct sockaddr_in6 *sin;
324         struct {
325                 struct sock_extended_err ee;
326                 struct sockaddr_in6      offender;
327         } errhdr;
328         int err;
329         int copied;
330
331         err = -EAGAIN;
332         skb = skb_dequeue(&sk->sk_error_queue);
333         if (skb == NULL)
334                 goto out;
335
336         copied = skb->len;
337         if (copied > len) {
338                 msg->msg_flags |= MSG_TRUNC;
339                 copied = len;
340         }
341         err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
342         if (err)
343                 goto out_free_skb;
344
345         sock_recv_timestamp(msg, sk, skb);
346
347         serr = SKB_EXT_ERR(skb);
348
349         sin = (struct sockaddr_in6 *)msg->msg_name;
350         if (sin) {
351                 const unsigned char *nh = skb_network_header(skb);
352                 sin->sin6_family = AF_INET6;
353                 sin->sin6_flowinfo = 0;
354                 sin->sin6_port = serr->port;
355                 sin->sin6_scope_id = 0;
356                 if (skb->protocol == htons(ETH_P_IPV6)) {
357                         sin->sin6_addr =
358                                 *(struct in6_addr *)(nh + serr->addr_offset);
359                         if (np->sndflow)
360                                 sin->sin6_flowinfo =
361                                         (*(__be32 *)(nh + serr->addr_offset - 24) &
362                                          IPV6_FLOWINFO_MASK);
363                         if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
364                                 sin->sin6_scope_id = IP6CB(skb)->iif;
365                 } else {
366                         ipv6_addr_set_v4mapped(*(__be32 *)(nh + serr->addr_offset),
367                                                &sin->sin6_addr);
368                 }
369         }
370
371         memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
372         sin = &errhdr.offender;
373         sin->sin6_family = AF_UNSPEC;
374         if (serr->ee.ee_origin != SO_EE_ORIGIN_LOCAL) {
375                 sin->sin6_family = AF_INET6;
376                 sin->sin6_flowinfo = 0;
377                 sin->sin6_scope_id = 0;
378                 if (skb->protocol == htons(ETH_P_IPV6)) {
379                         sin->sin6_addr = ipv6_hdr(skb)->saddr;
380                         if (np->rxopt.all)
381                                 datagram_recv_ctl(sk, msg, skb);
382                         if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
383                                 sin->sin6_scope_id = IP6CB(skb)->iif;
384                 } else {
385                         struct inet_sock *inet = inet_sk(sk);
386
387                         ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
388                                                &sin->sin6_addr);
389                         if (inet->cmsg_flags)
390                                 ip_cmsg_recv(msg, skb);
391                 }
392         }
393
394         put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr);
395
396         /* Now we could try to dump offended packet options */
397
398         msg->msg_flags |= MSG_ERRQUEUE;
399         err = copied;
400
401         /* Reset and regenerate socket error */
402         spin_lock_bh(&sk->sk_error_queue.lock);
403         sk->sk_err = 0;
404         if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
405                 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
406                 spin_unlock_bh(&sk->sk_error_queue.lock);
407                 sk->sk_error_report(sk);
408         } else {
409                 spin_unlock_bh(&sk->sk_error_queue.lock);
410         }
411
412 out_free_skb:
413         kfree_skb(skb);
414 out:
415         return err;
416 }
417
418 /*
419  *      Handle IPV6_RECVPATHMTU
420  */
421 int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len)
422 {
423         struct ipv6_pinfo *np = inet6_sk(sk);
424         struct sk_buff *skb;
425         struct sockaddr_in6 *sin;
426         struct ip6_mtuinfo mtu_info;
427         int err;
428         int copied;
429
430         err = -EAGAIN;
431         skb = xchg(&np->rxpmtu, NULL);
432         if (skb == NULL)
433                 goto out;
434
435         copied = skb->len;
436         if (copied > len) {
437                 msg->msg_flags |= MSG_TRUNC;
438                 copied = len;
439         }
440         err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
441         if (err)
442                 goto out_free_skb;
443
444         sock_recv_timestamp(msg, sk, skb);
445
446         memcpy(&mtu_info, IP6CBMTU(skb), sizeof(mtu_info));
447
448         sin = (struct sockaddr_in6 *)msg->msg_name;
449         if (sin) {
450                 sin->sin6_family = AF_INET6;
451                 sin->sin6_flowinfo = 0;
452                 sin->sin6_port = 0;
453                 sin->sin6_scope_id = mtu_info.ip6m_addr.sin6_scope_id;
454                 sin->sin6_addr = mtu_info.ip6m_addr.sin6_addr;
455         }
456
457         put_cmsg(msg, SOL_IPV6, IPV6_PATHMTU, sizeof(mtu_info), &mtu_info);
458
459         err = copied;
460
461 out_free_skb:
462         kfree_skb(skb);
463 out:
464         return err;
465 }
466
467
468 int datagram_recv_ctl(struct sock *sk, struct msghdr *msg, struct sk_buff *skb)
469 {
470         struct ipv6_pinfo *np = inet6_sk(sk);
471         struct inet6_skb_parm *opt = IP6CB(skb);
472         unsigned char *nh = skb_network_header(skb);
473
474         if (np->rxopt.bits.rxinfo) {
475                 struct in6_pktinfo src_info;
476
477                 src_info.ipi6_ifindex = opt->iif;
478                 src_info.ipi6_addr = ipv6_hdr(skb)->daddr;
479                 put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
480         }
481
482         if (np->rxopt.bits.rxhlim) {
483                 int hlim = ipv6_hdr(skb)->hop_limit;
484                 put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
485         }
486
487         if (np->rxopt.bits.rxtclass) {
488                 int tclass = (ntohl(*(__be32 *)ipv6_hdr(skb)) >> 20) & 0xff;
489                 put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
490         }
491
492         if (np->rxopt.bits.rxflow && (*(__be32 *)nh & IPV6_FLOWINFO_MASK)) {
493                 __be32 flowinfo = *(__be32 *)nh & IPV6_FLOWINFO_MASK;
494                 put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
495         }
496
497         /* HbH is allowed only once */
498         if (np->rxopt.bits.hopopts && opt->hop) {
499                 u8 *ptr = nh + opt->hop;
500                 put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr);
501         }
502
503         if (opt->lastopt &&
504             (np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) {
505                 /*
506                  * Silly enough, but we need to reparse in order to
507                  * report extension headers (except for HbH)
508                  * in order.
509                  *
510                  * Also note that IPV6_RECVRTHDRDSTOPTS is NOT
511                  * (and WILL NOT be) defined because
512                  * IPV6_RECVDSTOPTS is more generic. --yoshfuji
513                  */
514                 unsigned int off = sizeof(struct ipv6hdr);
515                 u8 nexthdr = ipv6_hdr(skb)->nexthdr;
516
517                 while (off <= opt->lastopt) {
518                         unsigned len;
519                         u8 *ptr = nh + off;
520
521                         switch(nexthdr) {
522                         case IPPROTO_DSTOPTS:
523                                 nexthdr = ptr[0];
524                                 len = (ptr[1] + 1) << 3;
525                                 if (np->rxopt.bits.dstopts)
526                                         put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, ptr);
527                                 break;
528                         case IPPROTO_ROUTING:
529                                 nexthdr = ptr[0];
530                                 len = (ptr[1] + 1) << 3;
531                                 if (np->rxopt.bits.srcrt)
532                                         put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, ptr);
533                                 break;
534                         case IPPROTO_AH:
535                                 nexthdr = ptr[0];
536                                 len = (ptr[1] + 2) << 2;
537                                 break;
538                         default:
539                                 nexthdr = ptr[0];
540                                 len = (ptr[1] + 1) << 3;
541                                 break;
542                         }
543
544                         off += len;
545                 }
546         }
547
548         /* socket options in old style */
549         if (np->rxopt.bits.rxoinfo) {
550                 struct in6_pktinfo src_info;
551
552                 src_info.ipi6_ifindex = opt->iif;
553                 src_info.ipi6_addr = ipv6_hdr(skb)->daddr;
554                 put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
555         }
556         if (np->rxopt.bits.rxohlim) {
557                 int hlim = ipv6_hdr(skb)->hop_limit;
558                 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
559         }
560         if (np->rxopt.bits.ohopopts && opt->hop) {
561                 u8 *ptr = nh + opt->hop;
562                 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, (ptr[1]+1)<<3, ptr);
563         }
564         if (np->rxopt.bits.odstopts && opt->dst0) {
565                 u8 *ptr = nh + opt->dst0;
566                 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
567         }
568         if (np->rxopt.bits.osrcrt && opt->srcrt) {
569                 struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt);
570                 put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, (rthdr->hdrlen+1) << 3, rthdr);
571         }
572         if (np->rxopt.bits.odstopts && opt->dst1) {
573                 u8 *ptr = nh + opt->dst1;
574                 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
575         }
576         if (np->rxopt.bits.rxorigdstaddr) {
577                 struct sockaddr_in6 sin6;
578                 u16 *ports = (u16 *) skb_transport_header(skb);
579
580                 if (skb_transport_offset(skb) + 4 <= skb->len) {
581                         /* All current transport protocols have the port numbers in the
582                          * first four bytes of the transport header and this function is
583                          * written with this assumption in mind.
584                          */
585
586                         sin6.sin6_family = AF_INET6;
587                         sin6.sin6_addr = ipv6_hdr(skb)->daddr;
588                         sin6.sin6_port = ports[1];
589                         sin6.sin6_flowinfo = 0;
590                         sin6.sin6_scope_id = 0;
591
592                         put_cmsg(msg, SOL_IPV6, IPV6_ORIGDSTADDR, sizeof(sin6), &sin6);
593                 }
594         }
595         return 0;
596 }
597
598 int datagram_send_ctl(struct net *net, struct sock *sk,
599                       struct msghdr *msg, struct flowi6 *fl6,
600                       struct ipv6_txoptions *opt,
601                       int *hlimit, int *tclass, int *dontfrag)
602 {
603         struct in6_pktinfo *src_info;
604         struct cmsghdr *cmsg;
605         struct ipv6_rt_hdr *rthdr;
606         struct ipv6_opt_hdr *hdr;
607         int len;
608         int err = 0;
609
610         for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
611                 int addr_type;
612
613                 if (!CMSG_OK(msg, cmsg)) {
614                         err = -EINVAL;
615                         goto exit_f;
616                 }
617
618                 if (cmsg->cmsg_level != SOL_IPV6)
619                         continue;
620
621                 switch (cmsg->cmsg_type) {
622                 case IPV6_PKTINFO:
623                 case IPV6_2292PKTINFO:
624                     {
625                         struct net_device *dev = NULL;
626
627                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) {
628                                 err = -EINVAL;
629                                 goto exit_f;
630                         }
631
632                         src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
633
634                         if (src_info->ipi6_ifindex) {
635                                 if (fl6->flowi6_oif &&
636                                     src_info->ipi6_ifindex != fl6->flowi6_oif)
637                                         return -EINVAL;
638                                 fl6->flowi6_oif = src_info->ipi6_ifindex;
639                         }
640
641                         addr_type = __ipv6_addr_type(&src_info->ipi6_addr);
642
643                         rcu_read_lock();
644                         if (fl6->flowi6_oif) {
645                                 dev = dev_get_by_index_rcu(net, fl6->flowi6_oif);
646                                 if (!dev) {
647                                         rcu_read_unlock();
648                                         return -ENODEV;
649                                 }
650                         } else if (addr_type & IPV6_ADDR_LINKLOCAL) {
651                                 rcu_read_unlock();
652                                 return -EINVAL;
653                         }
654
655                         if (addr_type != IPV6_ADDR_ANY) {
656                                 int strict = __ipv6_addr_src_scope(addr_type) <= IPV6_ADDR_SCOPE_LINKLOCAL;
657                                 if (!(inet_sk(sk)->freebind || inet_sk(sk)->transparent) &&
658                                     !ipv6_chk_addr(net, &src_info->ipi6_addr,
659                                                    strict ? dev : NULL, 0))
660                                         err = -EINVAL;
661                                 else
662                                         fl6->saddr = src_info->ipi6_addr;
663                         }
664
665                         rcu_read_unlock();
666
667                         if (err)
668                                 goto exit_f;
669
670                         break;
671                     }
672
673                 case IPV6_FLOWINFO:
674                         if (cmsg->cmsg_len < CMSG_LEN(4)) {
675                                 err = -EINVAL;
676                                 goto exit_f;
677                         }
678
679                         if (fl6->flowlabel&IPV6_FLOWINFO_MASK) {
680                                 if ((fl6->flowlabel^*(__be32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) {
681                                         err = -EINVAL;
682                                         goto exit_f;
683                                 }
684                         }
685                         fl6->flowlabel = IPV6_FLOWINFO_MASK & *(__be32 *)CMSG_DATA(cmsg);
686                         break;
687
688                 case IPV6_2292HOPOPTS:
689                 case IPV6_HOPOPTS:
690                         if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
691                                 err = -EINVAL;
692                                 goto exit_f;
693                         }
694
695                         hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
696                         len = ((hdr->hdrlen + 1) << 3);
697                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
698                                 err = -EINVAL;
699                                 goto exit_f;
700                         }
701                         if (!capable(CAP_NET_RAW)) {
702                                 err = -EPERM;
703                                 goto exit_f;
704                         }
705                         opt->opt_nflen += len;
706                         opt->hopopt = hdr;
707                         break;
708
709                 case IPV6_2292DSTOPTS:
710                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
711                                 err = -EINVAL;
712                                 goto exit_f;
713                         }
714
715                         hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
716                         len = ((hdr->hdrlen + 1) << 3);
717                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
718                                 err = -EINVAL;
719                                 goto exit_f;
720                         }
721                         if (!capable(CAP_NET_RAW)) {
722                                 err = -EPERM;
723                                 goto exit_f;
724                         }
725                         if (opt->dst1opt) {
726                                 err = -EINVAL;
727                                 goto exit_f;
728                         }
729                         opt->opt_flen += len;
730                         opt->dst1opt = hdr;
731                         break;
732
733                 case IPV6_DSTOPTS:
734                 case IPV6_RTHDRDSTOPTS:
735                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
736                                 err = -EINVAL;
737                                 goto exit_f;
738                         }
739
740                         hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
741                         len = ((hdr->hdrlen + 1) << 3);
742                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
743                                 err = -EINVAL;
744                                 goto exit_f;
745                         }
746                         if (!capable(CAP_NET_RAW)) {
747                                 err = -EPERM;
748                                 goto exit_f;
749                         }
750                         if (cmsg->cmsg_type == IPV6_DSTOPTS) {
751                                 opt->opt_flen += len;
752                                 opt->dst1opt = hdr;
753                         } else {
754                                 opt->opt_nflen += len;
755                                 opt->dst0opt = hdr;
756                         }
757                         break;
758
759                 case IPV6_2292RTHDR:
760                 case IPV6_RTHDR:
761                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) {
762                                 err = -EINVAL;
763                                 goto exit_f;
764                         }
765
766                         rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg);
767
768                         switch (rthdr->type) {
769 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
770                         case IPV6_SRCRT_TYPE_2:
771                                 if (rthdr->hdrlen != 2 ||
772                                     rthdr->segments_left != 1) {
773                                         err = -EINVAL;
774                                         goto exit_f;
775                                 }
776                                 break;
777 #endif
778                         default:
779                                 err = -EINVAL;
780                                 goto exit_f;
781                         }
782
783                         len = ((rthdr->hdrlen + 1) << 3);
784
785                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
786                                 err = -EINVAL;
787                                 goto exit_f;
788                         }
789
790                         /* segments left must also match */
791                         if ((rthdr->hdrlen >> 1) != rthdr->segments_left) {
792                                 err = -EINVAL;
793                                 goto exit_f;
794                         }
795
796                         opt->opt_nflen += len;
797                         opt->srcrt = rthdr;
798
799                         if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) {
800                                 int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3);
801
802                                 opt->opt_nflen += dsthdrlen;
803                                 opt->dst0opt = opt->dst1opt;
804                                 opt->dst1opt = NULL;
805                                 opt->opt_flen -= dsthdrlen;
806                         }
807
808                         break;
809
810                 case IPV6_2292HOPLIMIT:
811                 case IPV6_HOPLIMIT:
812                         if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
813                                 err = -EINVAL;
814                                 goto exit_f;
815                         }
816
817                         *hlimit = *(int *)CMSG_DATA(cmsg);
818                         if (*hlimit < -1 || *hlimit > 0xff) {
819                                 err = -EINVAL;
820                                 goto exit_f;
821                         }
822
823                         break;
824
825                 case IPV6_TCLASS:
826                     {
827                         int tc;
828
829                         err = -EINVAL;
830                         if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
831                                 goto exit_f;
832                         }
833
834                         tc = *(int *)CMSG_DATA(cmsg);
835                         if (tc < -1 || tc > 0xff)
836                                 goto exit_f;
837
838                         err = 0;
839                         *tclass = tc;
840
841                         break;
842                     }
843
844                 case IPV6_DONTFRAG:
845                     {
846                         int df;
847
848                         err = -EINVAL;
849                         if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
850                                 goto exit_f;
851                         }
852
853                         df = *(int *)CMSG_DATA(cmsg);
854                         if (df < 0 || df > 1)
855                                 goto exit_f;
856
857                         err = 0;
858                         *dontfrag = df;
859
860                         break;
861                     }
862                 default:
863                         LIMIT_NETDEBUG(KERN_DEBUG "invalid cmsg type: %d\n",
864                                        cmsg->cmsg_type);
865                         err = -EINVAL;
866                         goto exit_f;
867                 }
868         }
869
870 exit_f:
871         return err;
872 }