[SCTP]: Switch ->from_skb() to net-endian.
[linux-2.6] / net / sctp / ipv6.c
1 /* SCTP kernel reference Implementation
2  * (C) Copyright IBM Corp. 2002, 2004
3  * Copyright (c) 2001 Nokia, Inc.
4  * Copyright (c) 2001 La Monte H.P. Yarroll
5  * Copyright (c) 2002-2003 Intel Corp.
6  *
7  * This file is part of the SCTP kernel reference Implementation
8  *
9  * SCTP over IPv6.
10  *
11  * The SCTP reference implementation is free software;
12  * you can redistribute it and/or modify it under the terms of
13  * the GNU General Public License as published by
14  * the Free Software Foundation; either version 2, or (at your option)
15  * any later version.
16  *
17  * The SCTP reference implementation is distributed in the hope that it
18  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
19  *                 ************************
20  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
21  * See the GNU General Public License for more details.
22  *
23  * You should have received a copy of the GNU General Public License
24  * along with GNU CC; see the file COPYING.  If not, write to
25  * the Free Software Foundation, 59 Temple Place - Suite 330,
26  * Boston, MA 02111-1307, USA.
27  *
28  * Please send any bug reports or fixes you make to the
29  * email address(es):
30  *    lksctp developers <lksctp-developers@lists.sourceforge.net>
31  *
32  * Or submit a bug report through the following website:
33  *    http://www.sf.net/projects/lksctp
34  *
35  * Written or modified by:
36  *    Le Yanqun             <yanqun.le@nokia.com>
37  *    Hui Huang             <hui.huang@nokia.com>
38  *    La Monte H.P. Yarroll <piggy@acm.org>
39  *    Sridhar Samudrala     <sri@us.ibm.com>
40  *    Jon Grimm             <jgrimm@us.ibm.com>
41  *    Ardelle Fan           <ardelle.fan@intel.com>
42  *
43  * Based on:
44  *      linux/net/ipv6/tcp_ipv6.c
45  *
46  * Any bugs reported given to us we will try to fix... any fixes shared will
47  * be incorporated into the next SCTP release.
48  */
49
50 #include <linux/module.h>
51 #include <linux/errno.h>
52 #include <linux/types.h>
53 #include <linux/socket.h>
54 #include <linux/sockios.h>
55 #include <linux/net.h>
56 #include <linux/sched.h>
57 #include <linux/in.h>
58 #include <linux/in6.h>
59 #include <linux/netdevice.h>
60 #include <linux/init.h>
61 #include <linux/ipsec.h>
62
63 #include <linux/ipv6.h>
64 #include <linux/icmpv6.h>
65 #include <linux/random.h>
66 #include <linux/seq_file.h>
67
68 #include <net/protocol.h>
69 #include <net/ndisc.h>
70 #include <net/ip.h>
71 #include <net/ipv6.h>
72 #include <net/transp_v6.h>
73 #include <net/addrconf.h>
74 #include <net/ip6_route.h>
75 #include <net/inet_common.h>
76 #include <net/inet_ecn.h>
77 #include <net/sctp/sctp.h>
78
79 #include <asm/uaccess.h>
80
81 static struct notifier_block sctp_inet6addr_notifier = {
82         .notifier_call = sctp_inetaddr_event,
83 };
84
85 /* ICMP error handler. */
86 SCTP_STATIC void sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
87                              int type, int code, int offset, __be32 info)
88 {
89         struct inet6_dev *idev;
90         struct ipv6hdr *iph = (struct ipv6hdr *)skb->data;
91         struct sctphdr *sh = (struct sctphdr *)(skb->data + offset);
92         struct sock *sk;
93         struct sctp_association *asoc;
94         struct sctp_transport *transport;
95         struct ipv6_pinfo *np;
96         char *saveip, *savesctp;
97         int err;
98
99         idev = in6_dev_get(skb->dev);
100
101         /* Fix up skb to look at the embedded net header. */
102         saveip = skb->nh.raw;
103         savesctp  = skb->h.raw;
104         skb->nh.ipv6h = iph;
105         skb->h.raw = (char *)sh;
106         sk = sctp_err_lookup(AF_INET6, skb, sh, &asoc, &transport);
107         /* Put back, the original pointers. */
108         skb->nh.raw = saveip;
109         skb->h.raw = savesctp;
110         if (!sk) {
111                 ICMP6_INC_STATS_BH(idev, ICMP6_MIB_INERRORS);
112                 goto out;
113         }
114
115         /* Warning:  The sock lock is held.  Remember to call
116          * sctp_err_finish!
117          */
118
119         switch (type) {
120         case ICMPV6_PKT_TOOBIG:
121                 sctp_icmp_frag_needed(sk, asoc, transport, ntohl(info));
122                 goto out_unlock;
123         case ICMPV6_PARAMPROB:
124                 if (ICMPV6_UNK_NEXTHDR == code) {
125                         sctp_icmp_proto_unreachable(sk, asoc, transport);
126                         goto out_unlock;
127                 }
128                 break;
129         default:
130                 break;
131         }
132
133         np = inet6_sk(sk);
134         icmpv6_err_convert(type, code, &err);
135         if (!sock_owned_by_user(sk) && np->recverr) {
136                 sk->sk_err = err;
137                 sk->sk_error_report(sk);
138         } else {  /* Only an error on timeout */
139                 sk->sk_err_soft = err;
140         }
141
142 out_unlock:
143         sctp_err_finish(sk, asoc);
144 out:
145         if (likely(idev != NULL))
146                 in6_dev_put(idev);
147 }
148
149 /* Based on tcp_v6_xmit() in tcp_ipv6.c. */
150 static int sctp_v6_xmit(struct sk_buff *skb, struct sctp_transport *transport,
151                         int ipfragok)
152 {
153         struct sock *sk = skb->sk;
154         struct ipv6_pinfo *np = inet6_sk(sk);
155         struct flowi fl;
156
157         memset(&fl, 0, sizeof(fl));
158
159         fl.proto = sk->sk_protocol;
160
161         /* Fill in the dest address from the route entry passed with the skb
162          * and the source address from the transport.
163          */
164         ipv6_addr_copy(&fl.fl6_dst, &transport->ipaddr_h.v6.sin6_addr);
165         ipv6_addr_copy(&fl.fl6_src, &transport->saddr_h.v6.sin6_addr);
166
167         fl.fl6_flowlabel = np->flow_label;
168         IP6_ECN_flow_xmit(sk, fl.fl6_flowlabel);
169         if (ipv6_addr_type(&fl.fl6_src) & IPV6_ADDR_LINKLOCAL)
170                 fl.oif = transport->saddr_h.v6.sin6_scope_id;
171         else
172                 fl.oif = sk->sk_bound_dev_if;
173         fl.fl_ip_sport = inet_sk(sk)->sport;
174         fl.fl_ip_dport = transport->ipaddr_h.v6.sin6_port;
175
176         if (np->opt && np->opt->srcrt) {
177                 struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt;
178                 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
179         }
180
181         SCTP_DEBUG_PRINTK("%s: skb:%p, len:%d, "
182                           "src:" NIP6_FMT " dst:" NIP6_FMT "\n",
183                           __FUNCTION__, skb, skb->len,
184                           NIP6(fl.fl6_src), NIP6(fl.fl6_dst));
185
186         SCTP_INC_STATS(SCTP_MIB_OUTSCTPPACKS);
187
188         return ip6_xmit(sk, skb, &fl, np->opt, ipfragok);
189 }
190
191 /* Returns the dst cache entry for the given source and destination ip
192  * addresses.
193  */
194 static struct dst_entry *sctp_v6_get_dst(struct sctp_association *asoc,
195                                          union sctp_addr *daddr,
196                                          union sctp_addr *saddr)
197 {
198         struct dst_entry *dst;
199         struct flowi fl;
200
201         memset(&fl, 0, sizeof(fl));
202         ipv6_addr_copy(&fl.fl6_dst, &daddr->v6.sin6_addr);
203         if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
204                 fl.oif = daddr->v6.sin6_scope_id;
205         
206
207         SCTP_DEBUG_PRINTK("%s: DST=" NIP6_FMT " ",
208                           __FUNCTION__, NIP6(fl.fl6_dst));
209
210         if (saddr) {
211                 ipv6_addr_copy(&fl.fl6_src, &saddr->v6.sin6_addr);
212                 SCTP_DEBUG_PRINTK(
213                         "SRC=" NIP6_FMT " - ",
214                         NIP6(fl.fl6_src));
215         }
216
217         dst = ip6_route_output(NULL, &fl);
218         if (!dst->error) {
219                 struct rt6_info *rt;
220                 rt = (struct rt6_info *)dst;
221                 SCTP_DEBUG_PRINTK(
222                         "rt6_dst:" NIP6_FMT " rt6_src:" NIP6_FMT "\n",
223                         NIP6(rt->rt6i_dst.addr), NIP6(rt->rt6i_src.addr));
224                 return dst;
225         }
226         SCTP_DEBUG_PRINTK("NO ROUTE\n");
227         dst_release(dst);
228         return NULL;
229 }
230
231 /* Returns the number of consecutive initial bits that match in the 2 ipv6
232  * addresses.
233  */
234 static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
235                                          union sctp_addr *s2)
236 {
237         struct in6_addr *a1 = &s1->v6.sin6_addr;
238         struct in6_addr *a2 = &s2->v6.sin6_addr;
239         int i, j;
240
241         for (i = 0; i < 4 ; i++) {
242                 __be32 a1xora2;
243
244                 a1xora2 = a1->s6_addr32[i] ^ a2->s6_addr32[i];
245
246                 if ((j = fls(ntohl(a1xora2))))
247                         return (i * 32 + 32 - j);
248         }
249
250         return (i*32);
251 }
252
253 /* Fills in the source address(saddr) based on the destination address(daddr)
254  * and asoc's bind address list.
255  */
256 static void sctp_v6_get_saddr(struct sctp_association *asoc,
257                               struct dst_entry *dst,
258                               union sctp_addr *daddr,
259                               union sctp_addr *saddr)
260 {
261         struct sctp_bind_addr *bp;
262         rwlock_t *addr_lock;
263         struct sctp_sockaddr_entry *laddr;
264         struct list_head *pos;
265         sctp_scope_t scope;
266         union sctp_addr *baddr = NULL;
267         __u8 matchlen = 0;
268         __u8 bmatchlen;
269
270         SCTP_DEBUG_PRINTK("%s: asoc:%p dst:%p "
271                           "daddr:" NIP6_FMT " ",
272                           __FUNCTION__, asoc, dst, NIP6(daddr->v6.sin6_addr));
273
274         if (!asoc) {
275                 ipv6_get_saddr(dst, &daddr->v6.sin6_addr,&saddr->v6.sin6_addr);
276                 SCTP_DEBUG_PRINTK("saddr from ipv6_get_saddr: " NIP6_FMT "\n",
277                                   NIP6(saddr->v6.sin6_addr));
278                 return;
279         }
280
281         scope = sctp_scope(daddr);
282
283         bp = &asoc->base.bind_addr;
284         addr_lock = &asoc->base.addr_lock;
285
286         /* Go through the bind address list and find the best source address
287          * that matches the scope of the destination address.
288          */
289         sctp_read_lock(addr_lock);
290         list_for_each(pos, &bp->address_list) {
291                 laddr = list_entry(pos, struct sctp_sockaddr_entry, list);
292                 if ((laddr->use_as_src) &&
293                     (laddr->a_h.sa.sa_family == AF_INET6) &&
294                     (scope <= sctp_scope(&laddr->a_h))) {
295                         bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a_h);
296                         if (!baddr || (matchlen < bmatchlen)) {
297                                 baddr = &laddr->a_h;
298                                 matchlen = bmatchlen;
299                         }
300                 }
301         }
302
303         if (baddr) {
304                 memcpy(saddr, baddr, sizeof(union sctp_addr));
305                 SCTP_DEBUG_PRINTK("saddr: " NIP6_FMT "\n",
306                                   NIP6(saddr->v6.sin6_addr));
307         } else {
308                 printk(KERN_ERR "%s: asoc:%p Could not find a valid source "
309                        "address for the dest:" NIP6_FMT "\n",
310                        __FUNCTION__, asoc, NIP6(daddr->v6.sin6_addr));
311         }
312
313         sctp_read_unlock(addr_lock);
314 }
315
316 /* Make a copy of all potential local addresses. */
317 static void sctp_v6_copy_addrlist(struct list_head *addrlist,
318                                   struct net_device *dev)
319 {
320         struct inet6_dev *in6_dev;
321         struct inet6_ifaddr *ifp;
322         struct sctp_sockaddr_entry *addr;
323
324         rcu_read_lock();
325         if ((in6_dev = __in6_dev_get(dev)) == NULL) {
326                 rcu_read_unlock();
327                 return;
328         }
329
330         read_lock(&in6_dev->lock);
331         for (ifp = in6_dev->addr_list; ifp; ifp = ifp->if_next) {
332                 /* Add the address to the local list.  */
333                 addr = t_new(struct sctp_sockaddr_entry, GFP_ATOMIC);
334                 if (addr) {
335                         addr->a.v6.sin6_family = AF_INET6;
336                         addr->a.v6.sin6_port = 0;
337                         addr->a.v6.sin6_addr = ifp->addr;
338                         addr->a.v6.sin6_scope_id = dev->ifindex;
339                         addr->a_h = addr->a;
340                         INIT_LIST_HEAD(&addr->list);
341                         list_add_tail(&addr->list, addrlist);
342                 }
343         }
344
345         read_unlock(&in6_dev->lock);
346         rcu_read_unlock();
347 }
348
349 /* Initialize a sockaddr_storage from in incoming skb. */
350 static void sctp_v6_from_skb(union sctp_addr *addr,struct sk_buff *skb,
351                              int is_saddr)
352 {
353         void *from;
354         __be16 *port;
355         struct sctphdr *sh;
356
357         port = &addr->v6.sin6_port;
358         addr->v6.sin6_family = AF_INET6;
359         addr->v6.sin6_flowinfo = 0; /* FIXME */
360         addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif;
361
362         sh = (struct sctphdr *) skb->h.raw;
363         if (is_saddr) {
364                 *port  = sh->source;
365                 from = &skb->nh.ipv6h->saddr;
366         } else {
367                 *port = sh->dest;
368                 from = &skb->nh.ipv6h->daddr;
369         }
370         ipv6_addr_copy(&addr->v6.sin6_addr, from);
371 }
372
373 /* Initialize an sctp_addr from a socket. */
374 static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk)
375 {
376         addr->v6.sin6_family = AF_INET6;
377         addr->v6.sin6_port = inet_sk(sk)->num;
378         addr->v6.sin6_addr = inet6_sk(sk)->rcv_saddr;
379 }
380
381 /* Initialize sk->sk_rcv_saddr from sctp_addr. */
382 static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
383 {
384         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
385                 inet6_sk(sk)->rcv_saddr.s6_addr32[0] = 0;
386                 inet6_sk(sk)->rcv_saddr.s6_addr32[1] = 0;
387                 inet6_sk(sk)->rcv_saddr.s6_addr32[2] = htonl(0x0000ffff);
388                 inet6_sk(sk)->rcv_saddr.s6_addr32[3] =
389                         addr->v4.sin_addr.s_addr;
390         } else {
391                 inet6_sk(sk)->rcv_saddr = addr->v6.sin6_addr;
392         }
393 }
394
395 /* Initialize sk->sk_daddr from sctp_addr. */
396 static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
397 {
398         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
399                 inet6_sk(sk)->daddr.s6_addr32[0] = 0;
400                 inet6_sk(sk)->daddr.s6_addr32[1] = 0;
401                 inet6_sk(sk)->daddr.s6_addr32[2] = htonl(0x0000ffff);
402                 inet6_sk(sk)->daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
403         } else {
404                 inet6_sk(sk)->daddr = addr->v6.sin6_addr;
405         }
406 }
407
408 /* Initialize a sctp_addr from an address parameter. */
409 static void sctp_v6_from_addr_param(union sctp_addr *addr,
410                                     union sctp_addr_param *param,
411                                     __u16 port, int iif)
412 {
413         addr->v6.sin6_family = AF_INET6;
414         addr->v6.sin6_port = port;
415         addr->v6.sin6_flowinfo = 0; /* BUG */
416         ipv6_addr_copy(&addr->v6.sin6_addr, &param->v6.addr);
417         addr->v6.sin6_scope_id = iif;
418 }
419
420 /* Initialize an address parameter from a sctp_addr and return the length
421  * of the address parameter.
422  */
423 static int sctp_v6_to_addr_param(const union sctp_addr *addr,
424                                  union sctp_addr_param *param)
425 {
426         int length = sizeof(sctp_ipv6addr_param_t);
427
428         param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS;
429         param->v6.param_hdr.length = htons(length);
430         ipv6_addr_copy(&param->v6.addr, &addr->v6.sin6_addr);
431
432         return length;
433 }
434
435 /* Initialize a sctp_addr from a dst_entry. */
436 static void sctp_v6_dst_saddr(union sctp_addr *addr, struct dst_entry *dst,
437                               __be16 port)
438 {
439         struct rt6_info *rt = (struct rt6_info *)dst;
440         addr->sa.sa_family = AF_INET6;
441         addr->v6.sin6_port = port;
442         ipv6_addr_copy(&addr->v6.sin6_addr, &rt->rt6i_src.addr);
443 }
444
445 /* Compare addresses exactly.
446  * v4-mapped-v6 is also in consideration.
447  */
448 static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
449                             const union sctp_addr *addr2)
450 {
451         if (addr1->sa.sa_family != addr2->sa.sa_family) {
452                 if (addr1->sa.sa_family == AF_INET &&
453                     addr2->sa.sa_family == AF_INET6 &&
454                     IPV6_ADDR_MAPPED == ipv6_addr_type(&addr2->v6.sin6_addr)) {
455                         if (addr2->v6.sin6_port == addr1->v4.sin_port &&
456                             addr2->v6.sin6_addr.s6_addr32[3] ==
457                             addr1->v4.sin_addr.s_addr)
458                                 return 1;
459                 }
460                 if (addr2->sa.sa_family == AF_INET &&
461                     addr1->sa.sa_family == AF_INET6 &&
462                     IPV6_ADDR_MAPPED == ipv6_addr_type(&addr1->v6.sin6_addr)) {
463                         if (addr1->v6.sin6_port == addr2->v4.sin_port &&
464                             addr1->v6.sin6_addr.s6_addr32[3] ==
465                             addr2->v4.sin_addr.s_addr)
466                                 return 1;
467                 }
468                 return 0;
469         }
470         if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))
471                 return 0;
472         /* If this is a linklocal address, compare the scope_id. */
473         if (ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) {
474                 if (addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&
475                     (addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)) {
476                         return 0;
477                 }
478         }
479
480         return 1;
481 }
482
483 /* Initialize addr struct to INADDR_ANY. */
484 static void sctp_v6_inaddr_any(union sctp_addr *addr, unsigned short port)
485 {
486         memset(addr, 0x00, sizeof(union sctp_addr));
487         addr->v6.sin6_family = AF_INET6;
488         addr->v6.sin6_port = port;
489 }
490
491 /* Is this a wildcard address? */
492 static int sctp_v6_is_any(const union sctp_addr *addr)
493 {
494         return ipv6_addr_any(&addr->v6.sin6_addr);
495 }
496
497 /* Should this be available for binding?   */
498 static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp)
499 {
500         int type;
501         struct in6_addr *in6 = (struct in6_addr *)&addr->v6.sin6_addr;
502
503         type = ipv6_addr_type(in6);
504         if (IPV6_ADDR_ANY == type)
505                 return 1;
506         if (type == IPV6_ADDR_MAPPED) {
507                 if (sp && !sp->v4mapped)
508                         return 0;
509                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
510                         return 0;
511                 sctp_v6_map_v4(addr);
512                 return sctp_get_af_specific(AF_INET)->available(addr, sp);
513         }
514         if (!(type & IPV6_ADDR_UNICAST))
515                 return 0;
516
517         return ipv6_chk_addr(in6, NULL, 0);
518 }
519
520 /* This function checks if the address is a valid address to be used for
521  * SCTP.
522  *
523  * Output:
524  * Return 0 - If the address is a non-unicast or an illegal address.
525  * Return 1 - If the address is a unicast.
526  */
527 static int sctp_v6_addr_valid(union sctp_addr *addr,
528                               struct sctp_sock *sp,
529                               const struct sk_buff *skb)
530 {
531         int ret = ipv6_addr_type(&addr->v6.sin6_addr);
532
533         /* Support v4-mapped-v6 address. */
534         if (ret == IPV6_ADDR_MAPPED) {
535                 /* Note: This routine is used in input, so v4-mapped-v6
536                  * are disallowed here when there is no sctp_sock.
537                  */
538                 if (!sp || !sp->v4mapped)
539                         return 0;
540                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
541                         return 0;
542                 sctp_v6_map_v4(addr);
543                 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb);
544         }
545
546         /* Is this a non-unicast address */
547         if (!(ret & IPV6_ADDR_UNICAST))
548                 return 0;
549
550         return 1;
551 }
552
553 /* What is the scope of 'addr'?  */
554 static sctp_scope_t sctp_v6_scope(union sctp_addr *addr)
555 {
556         int v6scope;
557         sctp_scope_t retval;
558
559         /* The IPv6 scope is really a set of bit fields.
560          * See IFA_* in <net/if_inet6.h>.  Map to a generic SCTP scope.
561          */
562
563         v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
564         switch (v6scope) {
565         case IFA_HOST:
566                 retval = SCTP_SCOPE_LOOPBACK;
567                 break;
568         case IFA_LINK:
569                 retval = SCTP_SCOPE_LINK;
570                 break;
571         case IFA_SITE:
572                 retval = SCTP_SCOPE_PRIVATE;
573                 break;
574         default:
575                 retval = SCTP_SCOPE_GLOBAL;
576                 break;
577         };
578
579         return retval;
580 }
581
582 /* Create and initialize a new sk for the socket to be returned by accept(). */
583 static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
584                                              struct sctp_association *asoc)
585 {
586         struct inet_sock *inet = inet_sk(sk);
587         struct sock *newsk;
588         struct inet_sock *newinet;
589         struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
590         struct sctp6_sock *newsctp6sk;
591
592         newsk = sk_alloc(PF_INET6, GFP_KERNEL, sk->sk_prot, 1);
593         if (!newsk)
594                 goto out;
595
596         sock_init_data(NULL, newsk);
597
598         newsk->sk_type = SOCK_STREAM;
599
600         newsk->sk_prot = sk->sk_prot;
601         newsk->sk_no_check = sk->sk_no_check;
602         newsk->sk_reuse = sk->sk_reuse;
603
604         newsk->sk_destruct = inet_sock_destruct;
605         newsk->sk_family = PF_INET6;
606         newsk->sk_protocol = IPPROTO_SCTP;
607         newsk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
608         newsk->sk_shutdown = sk->sk_shutdown;
609         sock_reset_flag(sk, SOCK_ZAPPED);
610
611         newsctp6sk = (struct sctp6_sock *)newsk;
612         inet_sk(newsk)->pinet6 = &newsctp6sk->inet6;
613
614         newinet = inet_sk(newsk);
615         newnp = inet6_sk(newsk);
616
617         memcpy(newnp, np, sizeof(struct ipv6_pinfo));
618
619         /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
620          * and getpeername().
621          */
622         newinet->sport = inet->sport;
623         newnp->saddr = np->saddr;
624         newnp->rcv_saddr = np->rcv_saddr;
625         newinet->dport = htons(asoc->peer.port);
626         sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
627
628         /* Init the ipv4 part of the socket since we can have sockets
629          * using v6 API for ipv4.
630          */
631         newinet->uc_ttl = -1;
632         newinet->mc_loop = 1;
633         newinet->mc_ttl = 1;
634         newinet->mc_index = 0;
635         newinet->mc_list = NULL;
636
637         if (ipv4_config.no_pmtu_disc)
638                 newinet->pmtudisc = IP_PMTUDISC_DONT;
639         else
640                 newinet->pmtudisc = IP_PMTUDISC_WANT;
641
642         sk_refcnt_debug_inc(newsk);
643
644         if (newsk->sk_prot->init(newsk)) {
645                 sk_common_release(newsk);
646                 newsk = NULL;
647         }
648
649 out:
650         return newsk;
651 }
652
653 /* Map v4 address to mapped v6 address */
654 static void sctp_v6_addr_v4map(struct sctp_sock *sp, union sctp_addr *addr)
655 {
656         if (sp->v4mapped && AF_INET == addr->sa.sa_family)
657                 sctp_v4_map_v6(addr);
658 }
659
660 /* Where did this skb come from?  */
661 static int sctp_v6_skb_iif(const struct sk_buff *skb)
662 {
663         struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb;
664         return opt->iif;
665 }
666
667 /* Was this packet marked by Explicit Congestion Notification? */
668 static int sctp_v6_is_ce(const struct sk_buff *skb)
669 {
670         return *((__u32 *)(skb->nh.ipv6h)) & htonl(1<<20);
671 }
672
673 /* Dump the v6 addr to the seq file. */
674 static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
675 {
676         seq_printf(seq, NIP6_FMT " ", NIP6(addr->v6.sin6_addr));
677 }
678
679 /* Initialize a PF_INET6 socket msg_name. */
680 static void sctp_inet6_msgname(char *msgname, int *addr_len)
681 {
682         struct sockaddr_in6 *sin6;
683
684         sin6 = (struct sockaddr_in6 *)msgname;
685         sin6->sin6_family = AF_INET6;
686         sin6->sin6_flowinfo = 0;
687         sin6->sin6_scope_id = 0; /*FIXME */
688         *addr_len = sizeof(struct sockaddr_in6);
689 }
690
691 /* Initialize a PF_INET msgname from a ulpevent. */
692 static void sctp_inet6_event_msgname(struct sctp_ulpevent *event,
693                                      char *msgname, int *addrlen)
694 {
695         struct sockaddr_in6 *sin6, *sin6from;
696
697         if (msgname) {
698                 union sctp_addr *addr;
699                 struct sctp_association *asoc;
700
701                 asoc = event->asoc;
702                 sctp_inet6_msgname(msgname, addrlen);
703                 sin6 = (struct sockaddr_in6 *)msgname;
704                 sin6->sin6_port = htons(asoc->peer.port);
705                 addr = &asoc->peer.primary_addr;
706
707                 /* Note: If we go to a common v6 format, this code
708                  * will change.
709                  */
710
711                 /* Map ipv4 address into v4-mapped-on-v6 address.  */
712                 if (sctp_sk(asoc->base.sk)->v4mapped &&
713                     AF_INET == addr->sa.sa_family) {
714                         sctp_v4_map_v6((union sctp_addr *)sin6);
715                         sin6->sin6_addr.s6_addr32[3] =
716                                 addr->v4.sin_addr.s_addr;
717                         return;
718                 }
719
720                 sin6from = &asoc->peer.primary_addr.v6;
721                 ipv6_addr_copy(&sin6->sin6_addr, &sin6from->sin6_addr);
722                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
723                         sin6->sin6_scope_id = sin6from->sin6_scope_id;
724         }
725 }
726
727 /* Initialize a msg_name from an inbound skb. */
728 static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname,
729                                    int *addr_len)
730 {
731         struct sctphdr *sh;
732         struct sockaddr_in6 *sin6;
733
734         if (msgname) {
735                 sctp_inet6_msgname(msgname, addr_len);
736                 sin6 = (struct sockaddr_in6 *)msgname;
737                 sh = (struct sctphdr *)skb->h.raw;
738                 sin6->sin6_port = sh->source;
739
740                 /* Map ipv4 address into v4-mapped-on-v6 address. */
741                 if (sctp_sk(skb->sk)->v4mapped &&
742                     skb->nh.iph->version == 4) {
743                         sctp_v4_map_v6((union sctp_addr *)sin6);
744                         sin6->sin6_addr.s6_addr32[3] = skb->nh.iph->saddr;
745                         return;
746                 }
747
748                 /* Otherwise, just copy the v6 address. */
749                 ipv6_addr_copy(&sin6->sin6_addr, &skb->nh.ipv6h->saddr);
750                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) {
751                         struct sctp_ulpevent *ev = sctp_skb2event(skb);
752                         sin6->sin6_scope_id = ev->iif;
753                 }
754         }
755 }
756
757 /* Do we support this AF? */
758 static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp)
759 {
760         switch (family) {
761         case AF_INET6:
762                 return 1;
763         /* v4-mapped-v6 addresses */
764         case AF_INET:
765                 if (!__ipv6_only_sock(sctp_opt2sk(sp)) && sp->v4mapped)
766                         return 1;
767         default:
768                 return 0;
769         }
770 }
771
772 /* Address matching with wildcards allowed.  This extra level
773  * of indirection lets us choose whether a PF_INET6 should
774  * disallow any v4 addresses if we so choose.
775  */
776 static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
777                                const union sctp_addr *addr2,
778                                struct sctp_sock *opt)
779 {
780         struct sctp_af *af1, *af2;
781
782         af1 = sctp_get_af_specific(addr1->sa.sa_family);
783         af2 = sctp_get_af_specific(addr2->sa.sa_family);
784
785         if (!af1 || !af2)
786                 return 0;
787         /* Today, wildcard AF_INET/AF_INET6. */
788         if (sctp_is_any(addr1) || sctp_is_any(addr2))
789                 return 1;
790
791         if (addr1->sa.sa_family != addr2->sa.sa_family)
792                 return 0;
793
794         return af1->cmp_addr(addr1, addr2);
795 }
796
797 /* Verify that the provided sockaddr looks bindable.   Common verification,
798  * has already been taken care of.
799  */
800 static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
801 {
802         struct sctp_af *af;
803
804         /* ASSERT: address family has already been verified. */
805         if (addr->sa.sa_family != AF_INET6)
806                 af = sctp_get_af_specific(addr->sa.sa_family);
807         else {
808                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
809                 struct net_device *dev;
810
811                 if (type & IPV6_ADDR_LINKLOCAL) {
812                         if (!addr->v6.sin6_scope_id)
813                                 return 0;
814                         dev = dev_get_by_index(addr->v6.sin6_scope_id);
815                         if (!dev)
816                                 return 0;
817                         dev_put(dev);
818                 }
819                 af = opt->pf->af;
820         }
821         return af->available(addr, opt);
822 }
823
824 /* Verify that the provided sockaddr looks sendable.   Common verification,
825  * has already been taken care of.
826  */
827 static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
828 {
829         struct sctp_af *af = NULL;
830
831         /* ASSERT: address family has already been verified. */
832         if (addr->sa.sa_family != AF_INET6)
833                 af = sctp_get_af_specific(addr->sa.sa_family);
834         else {
835                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
836                 struct net_device *dev;
837
838                 if (type & IPV6_ADDR_LINKLOCAL) {
839                         if (!addr->v6.sin6_scope_id)
840                                 return 0;
841                         dev = dev_get_by_index(addr->v6.sin6_scope_id);
842                         if (!dev)
843                                 return 0;
844                         dev_put(dev);
845                 }
846                 af = opt->pf->af;
847         }
848
849         return af != NULL;
850 }
851
852 /* Fill in Supported Address Type information for INIT and INIT-ACK
853  * chunks.   Note: In the future, we may want to look at sock options
854  * to determine whether a PF_INET6 socket really wants to have IPV4
855  * addresses.
856  * Returns number of addresses supported.
857  */
858 static int sctp_inet6_supported_addrs(const struct sctp_sock *opt,
859                                       __u16 *types)
860 {
861         types[0] = SCTP_PARAM_IPV4_ADDRESS;
862         types[1] = SCTP_PARAM_IPV6_ADDRESS;
863         return 2;
864 }
865
866 static const struct proto_ops inet6_seqpacket_ops = {
867         .family            = PF_INET6,
868         .owner             = THIS_MODULE,
869         .release           = inet6_release,
870         .bind              = inet6_bind,
871         .connect           = inet_dgram_connect,
872         .socketpair        = sock_no_socketpair,
873         .accept            = inet_accept,
874         .getname           = inet6_getname,
875         .poll              = sctp_poll,
876         .ioctl             = inet6_ioctl,
877         .listen            = sctp_inet_listen,
878         .shutdown          = inet_shutdown,
879         .setsockopt        = sock_common_setsockopt,
880         .getsockopt        = sock_common_getsockopt,
881         .sendmsg           = inet_sendmsg,
882         .recvmsg           = sock_common_recvmsg,
883         .mmap              = sock_no_mmap,
884 #ifdef CONFIG_COMPAT
885         .compat_setsockopt = compat_sock_common_setsockopt,
886         .compat_getsockopt = compat_sock_common_getsockopt,
887 #endif
888 };
889
890 static struct inet_protosw sctpv6_seqpacket_protosw = {
891         .type          = SOCK_SEQPACKET,
892         .protocol      = IPPROTO_SCTP,
893         .prot          = &sctpv6_prot,
894         .ops           = &inet6_seqpacket_ops,
895         .capability    = -1,
896         .no_check      = 0,
897         .flags         = SCTP_PROTOSW_FLAG
898 };
899 static struct inet_protosw sctpv6_stream_protosw = {
900         .type          = SOCK_STREAM,
901         .protocol      = IPPROTO_SCTP,
902         .prot          = &sctpv6_prot,
903         .ops           = &inet6_seqpacket_ops,
904         .capability    = -1,
905         .no_check      = 0,
906         .flags         = SCTP_PROTOSW_FLAG,
907 };
908
909 static int sctp6_rcv(struct sk_buff **pskb)
910 {
911         return sctp_rcv(*pskb) ? -1 : 0;
912 }
913
914 static struct inet6_protocol sctpv6_protocol = {
915         .handler      = sctp6_rcv,
916         .err_handler  = sctp_v6_err,
917         .flags        = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
918 };
919
920 static struct sctp_af sctp_ipv6_specific = {
921         .sa_family         = AF_INET6,
922         .sctp_xmit         = sctp_v6_xmit,
923         .setsockopt        = ipv6_setsockopt,
924         .getsockopt        = ipv6_getsockopt,
925         .get_dst           = sctp_v6_get_dst,
926         .get_saddr         = sctp_v6_get_saddr,
927         .copy_addrlist     = sctp_v6_copy_addrlist,
928         .from_skb          = sctp_v6_from_skb,
929         .from_sk           = sctp_v6_from_sk,
930         .to_sk_saddr       = sctp_v6_to_sk_saddr,
931         .to_sk_daddr       = sctp_v6_to_sk_daddr,
932         .from_addr_param   = sctp_v6_from_addr_param,
933         .to_addr_param     = sctp_v6_to_addr_param,
934         .dst_saddr         = sctp_v6_dst_saddr,
935         .cmp_addr          = sctp_v6_cmp_addr,
936         .scope             = sctp_v6_scope,
937         .addr_valid        = sctp_v6_addr_valid,
938         .inaddr_any        = sctp_v6_inaddr_any,
939         .is_any            = sctp_v6_is_any,
940         .available         = sctp_v6_available,
941         .skb_iif           = sctp_v6_skb_iif,
942         .is_ce             = sctp_v6_is_ce,
943         .seq_dump_addr     = sctp_v6_seq_dump_addr,
944         .net_header_len    = sizeof(struct ipv6hdr),
945         .sockaddr_len      = sizeof(struct sockaddr_in6),
946 #ifdef CONFIG_COMPAT
947         .compat_setsockopt = compat_ipv6_setsockopt,
948         .compat_getsockopt = compat_ipv6_getsockopt,
949 #endif
950 };
951
952 static struct sctp_pf sctp_pf_inet6_specific = {
953         .event_msgname = sctp_inet6_event_msgname,
954         .skb_msgname   = sctp_inet6_skb_msgname,
955         .af_supported  = sctp_inet6_af_supported,
956         .cmp_addr      = sctp_inet6_cmp_addr,
957         .bind_verify   = sctp_inet6_bind_verify,
958         .send_verify   = sctp_inet6_send_verify,
959         .supported_addrs = sctp_inet6_supported_addrs,
960         .create_accept_sk = sctp_v6_create_accept_sk,
961         .addr_v4map    = sctp_v6_addr_v4map,
962         .af            = &sctp_ipv6_specific,
963 };
964
965 /* Initialize IPv6 support and register with inet6 stack.  */
966 int sctp_v6_init(void)
967 {
968         int rc = proto_register(&sctpv6_prot, 1);
969
970         if (rc)
971                 goto out;
972         /* Register inet6 protocol. */
973         rc = -EAGAIN;
974         if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
975                 goto out_unregister_sctp_proto;
976
977         /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
978         inet6_register_protosw(&sctpv6_seqpacket_protosw);
979         inet6_register_protosw(&sctpv6_stream_protosw);
980
981         /* Register the SCTP specific PF_INET6 functions. */
982         sctp_register_pf(&sctp_pf_inet6_specific, PF_INET6);
983
984         /* Register the SCTP specific AF_INET6 functions. */
985         sctp_register_af(&sctp_ipv6_specific);
986
987         /* Register notifier for inet6 address additions/deletions. */
988         register_inet6addr_notifier(&sctp_inet6addr_notifier);
989         rc = 0;
990 out:
991         return rc;
992 out_unregister_sctp_proto:
993         proto_unregister(&sctpv6_prot);
994         goto out;
995 }
996
997 /* IPv6 specific exit support. */
998 void sctp_v6_exit(void)
999 {
1000         list_del(&sctp_ipv6_specific.list);
1001         inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
1002         inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
1003         inet6_unregister_protosw(&sctpv6_stream_protosw);
1004         unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
1005         proto_unregister(&sctpv6_prot);
1006 }