sctp: do not inherit ipv6_{mc|ac|fl}_list from parent
[pandora-kernel.git] / net / sctp / ipv6.c
1 /* SCTP kernel 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 implementation
8  *
9  * SCTP over IPv6.
10  *
11  * This SCTP 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  * This SCTP 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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
51
52 #include <linux/module.h>
53 #include <linux/errno.h>
54 #include <linux/types.h>
55 #include <linux/socket.h>
56 #include <linux/sockios.h>
57 #include <linux/net.h>
58 #include <linux/in.h>
59 #include <linux/in6.h>
60 #include <linux/netdevice.h>
61 #include <linux/init.h>
62 #include <linux/ipsec.h>
63 #include <linux/slab.h>
64
65 #include <linux/ipv6.h>
66 #include <linux/icmpv6.h>
67 #include <linux/random.h>
68 #include <linux/seq_file.h>
69
70 #include <net/protocol.h>
71 #include <net/ndisc.h>
72 #include <net/ip.h>
73 #include <net/ipv6.h>
74 #include <net/transp_v6.h>
75 #include <net/addrconf.h>
76 #include <net/ip6_route.h>
77 #include <net/inet_common.h>
78 #include <net/inet_ecn.h>
79 #include <net/sctp/sctp.h>
80
81 #include <asm/uaccess.h>
82
83 static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
84                                          union sctp_addr *s2);
85 static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr,
86                               __be16 port);
87 static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
88                             const union sctp_addr *addr2);
89
90 /* Event handler for inet6 address addition/deletion events.
91  * The sctp_local_addr_list needs to be protocted by a spin lock since
92  * multiple notifiers (say IPv4 and IPv6) may be running at the same
93  * time and thus corrupt the list.
94  * The reader side is protected with RCU.
95  */
96 static int sctp_inet6addr_event(struct notifier_block *this, unsigned long ev,
97                                 void *ptr)
98 {
99         struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
100         struct sctp_sockaddr_entry *addr = NULL;
101         struct sctp_sockaddr_entry *temp;
102         int found = 0;
103
104         switch (ev) {
105         case NETDEV_UP:
106                 addr = kmalloc(sizeof(struct sctp_sockaddr_entry), GFP_ATOMIC);
107                 if (addr) {
108                         addr->a.v6.sin6_family = AF_INET6;
109                         addr->a.v6.sin6_port = 0;
110                         ipv6_addr_copy(&addr->a.v6.sin6_addr, &ifa->addr);
111                         addr->a.v6.sin6_scope_id = ifa->idev->dev->ifindex;
112                         addr->valid = 1;
113                         spin_lock_bh(&sctp_local_addr_lock);
114                         list_add_tail_rcu(&addr->list, &sctp_local_addr_list);
115                         sctp_addr_wq_mgmt(addr, SCTP_ADDR_NEW);
116                         spin_unlock_bh(&sctp_local_addr_lock);
117                 }
118                 break;
119         case NETDEV_DOWN:
120                 spin_lock_bh(&sctp_local_addr_lock);
121                 list_for_each_entry_safe(addr, temp,
122                                         &sctp_local_addr_list, list) {
123                         if (addr->a.sa.sa_family == AF_INET6 &&
124                                         ipv6_addr_equal(&addr->a.v6.sin6_addr,
125                                                 &ifa->addr)) {
126                                 sctp_addr_wq_mgmt(addr, SCTP_ADDR_DEL);
127                                 found = 1;
128                                 addr->valid = 0;
129                                 list_del_rcu(&addr->list);
130                                 break;
131                         }
132                 }
133                 spin_unlock_bh(&sctp_local_addr_lock);
134                 if (found)
135                         kfree_rcu(addr, rcu);
136                 break;
137         }
138
139         return NOTIFY_DONE;
140 }
141
142 static struct notifier_block sctp_inet6addr_notifier = {
143         .notifier_call = sctp_inet6addr_event,
144 };
145
146 /* ICMP error handler. */
147 SCTP_STATIC void sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
148                              u8 type, u8 code, int offset, __be32 info)
149 {
150         struct inet6_dev *idev;
151         struct sock *sk;
152         struct sctp_association *asoc;
153         struct sctp_transport *transport;
154         struct ipv6_pinfo *np;
155         sk_buff_data_t saveip, savesctp;
156         int err;
157
158         idev = in6_dev_get(skb->dev);
159
160         /* Fix up skb to look at the embedded net header. */
161         saveip   = skb->network_header;
162         savesctp = skb->transport_header;
163         skb_reset_network_header(skb);
164         skb_set_transport_header(skb, offset);
165         sk = sctp_err_lookup(AF_INET6, skb, sctp_hdr(skb), &asoc, &transport);
166         /* Put back, the original pointers. */
167         skb->network_header   = saveip;
168         skb->transport_header = savesctp;
169         if (!sk) {
170                 ICMP6_INC_STATS_BH(dev_net(skb->dev), idev, ICMP6_MIB_INERRORS);
171                 goto out;
172         }
173
174         /* Warning:  The sock lock is held.  Remember to call
175          * sctp_err_finish!
176          */
177
178         switch (type) {
179         case ICMPV6_PKT_TOOBIG:
180                 sctp_icmp_frag_needed(sk, asoc, transport, ntohl(info));
181                 goto out_unlock;
182         case ICMPV6_PARAMPROB:
183                 if (ICMPV6_UNK_NEXTHDR == code) {
184                         sctp_icmp_proto_unreachable(sk, asoc, transport);
185                         goto out_unlock;
186                 }
187                 break;
188         default:
189                 break;
190         }
191
192         np = inet6_sk(sk);
193         icmpv6_err_convert(type, code, &err);
194         if (!sock_owned_by_user(sk) && np->recverr) {
195                 sk->sk_err = err;
196                 sk->sk_error_report(sk);
197         } else {  /* Only an error on timeout */
198                 sk->sk_err_soft = err;
199         }
200
201 out_unlock:
202         sctp_err_finish(sk, asoc);
203 out:
204         if (likely(idev != NULL))
205                 in6_dev_put(idev);
206 }
207
208 static int sctp_v6_xmit(struct sk_buff *skb, struct sctp_transport *transport)
209 {
210         struct sock *sk = skb->sk;
211         struct ipv6_pinfo *np = inet6_sk(sk);
212         struct flowi6 *fl6 = &transport->fl.u.ip6;
213
214         SCTP_DEBUG_PRINTK("%s: skb:%p, len:%d, src:%pI6 dst:%pI6\n",
215                           __func__, skb, skb->len,
216                           &fl6->saddr, &fl6->daddr);
217
218         IP6_ECN_flow_xmit(sk, fl6->flowlabel);
219
220         if (!(transport->param_flags & SPP_PMTUD_ENABLE))
221                 skb->local_df = 1;
222
223         SCTP_INC_STATS(SCTP_MIB_OUTSCTPPACKS);
224
225         return ip6_xmit(sk, skb, fl6, np->opt, np->tclass);
226 }
227
228 /* Returns the dst cache entry for the given source and destination ip
229  * addresses.
230  */
231 static void sctp_v6_get_dst(struct sctp_transport *t, union sctp_addr *saddr,
232                             struct flowi *fl, struct sock *sk)
233 {
234         struct sctp_association *asoc = t->asoc;
235         struct dst_entry *dst = NULL;
236         struct flowi6 *fl6 = &fl->u.ip6;
237         struct sctp_bind_addr *bp;
238         struct ipv6_pinfo *np = inet6_sk(sk);
239         struct sctp_sockaddr_entry *laddr;
240         union sctp_addr *baddr = NULL;
241         union sctp_addr *daddr = &t->ipaddr;
242         union sctp_addr dst_saddr;
243         struct in6_addr *final_p, final;
244         __u8 matchlen = 0;
245         __u8 bmatchlen;
246         sctp_scope_t scope;
247
248         memset(fl6, 0, sizeof(struct flowi6));
249         ipv6_addr_copy(&fl6->daddr, &daddr->v6.sin6_addr);
250         fl6->fl6_dport = daddr->v6.sin6_port;
251         fl6->flowi6_proto = IPPROTO_SCTP;
252         if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
253                 fl6->flowi6_oif = daddr->v6.sin6_scope_id;
254
255         SCTP_DEBUG_PRINTK("%s: DST=%pI6 ", __func__, &fl6->daddr);
256
257         if (asoc)
258                 fl6->fl6_sport = htons(asoc->base.bind_addr.port);
259
260         if (saddr) {
261                 ipv6_addr_copy(&fl6->saddr, &saddr->v6.sin6_addr);
262                 fl6->fl6_sport = saddr->v6.sin6_port;
263                 SCTP_DEBUG_PRINTK("SRC=%pI6 - ", &fl6->saddr);
264         }
265
266         final_p = fl6_update_dst(fl6, np->opt, &final);
267         dst = ip6_dst_lookup_flow(sk, fl6, final_p, false);
268         if (!asoc || saddr)
269                 goto out;
270
271         bp = &asoc->base.bind_addr;
272         scope = sctp_scope(daddr);
273         /* ip6_dst_lookup has filled in the fl6->saddr for us.  Check
274          * to see if we can use it.
275          */
276         if (!IS_ERR(dst)) {
277                 /* Walk through the bind address list and look for a bind
278                  * address that matches the source address of the returned dst.
279                  */
280                 sctp_v6_to_addr(&dst_saddr, &fl6->saddr, htons(bp->port));
281                 rcu_read_lock();
282                 list_for_each_entry_rcu(laddr, &bp->address_list, list) {
283                         if (!laddr->valid || (laddr->state != SCTP_ADDR_SRC))
284                                 continue;
285
286                         /* Do not compare against v4 addrs */
287                         if ((laddr->a.sa.sa_family == AF_INET6) &&
288                             (sctp_v6_cmp_addr(&dst_saddr, &laddr->a))) {
289                                 rcu_read_unlock();
290                                 goto out;
291                         }
292                 }
293                 rcu_read_unlock();
294                 /* None of the bound addresses match the source address of the
295                  * dst. So release it.
296                  */
297                 dst_release(dst);
298                 dst = NULL;
299         }
300
301         /* Walk through the bind address list and try to get the
302          * best source address for a given destination.
303          */
304         rcu_read_lock();
305         list_for_each_entry_rcu(laddr, &bp->address_list, list) {
306                 if (!laddr->valid && laddr->state != SCTP_ADDR_SRC)
307                         continue;
308                 if ((laddr->a.sa.sa_family == AF_INET6) &&
309                     (scope <= sctp_scope(&laddr->a))) {
310                         bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a);
311                         if (!baddr || (matchlen < bmatchlen)) {
312                                 baddr = &laddr->a;
313                                 matchlen = bmatchlen;
314                         }
315                 }
316         }
317         if (baddr) {
318                 ipv6_addr_copy(&fl6->saddr, &baddr->v6.sin6_addr);
319                 fl6->fl6_sport = baddr->v6.sin6_port;
320                 final_p = fl6_update_dst(fl6, np->opt, &final);
321                 dst = ip6_dst_lookup_flow(sk, fl6, final_p, false);
322         }
323         rcu_read_unlock();
324
325 out:
326         if (!IS_ERR(dst)) {
327                 struct rt6_info *rt;
328                 rt = (struct rt6_info *)dst;
329                 t->dst = dst;
330                 SCTP_DEBUG_PRINTK("rt6_dst:%pI6 rt6_src:%pI6\n",
331                         &rt->rt6i_dst.addr, &fl6->saddr);
332         } else {
333                 t->dst = NULL;
334                 SCTP_DEBUG_PRINTK("NO ROUTE\n");
335         }
336 }
337
338 /* Returns the number of consecutive initial bits that match in the 2 ipv6
339  * addresses.
340  */
341 static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
342                                          union sctp_addr *s2)
343 {
344         return ipv6_addr_diff(&s1->v6.sin6_addr, &s2->v6.sin6_addr);
345 }
346
347 /* Fills in the source address(saddr) based on the destination address(daddr)
348  * and asoc's bind address list.
349  */
350 static void sctp_v6_get_saddr(struct sctp_sock *sk,
351                               struct sctp_transport *t,
352                               struct flowi *fl)
353 {
354         struct flowi6 *fl6 = &fl->u.ip6;
355         union sctp_addr *saddr = &t->saddr;
356
357         SCTP_DEBUG_PRINTK("%s: asoc:%p dst:%p\n", __func__, t->asoc, t->dst);
358
359         if (t->dst) {
360                 saddr->v6.sin6_family = AF_INET6;
361                 ipv6_addr_copy(&saddr->v6.sin6_addr, &fl6->saddr);
362         }
363 }
364
365 /* Make a copy of all potential local addresses. */
366 static void sctp_v6_copy_addrlist(struct list_head *addrlist,
367                                   struct net_device *dev)
368 {
369         struct inet6_dev *in6_dev;
370         struct inet6_ifaddr *ifp;
371         struct sctp_sockaddr_entry *addr;
372
373         rcu_read_lock();
374         if ((in6_dev = __in6_dev_get(dev)) == NULL) {
375                 rcu_read_unlock();
376                 return;
377         }
378
379         read_lock_bh(&in6_dev->lock);
380         list_for_each_entry(ifp, &in6_dev->addr_list, if_list) {
381                 /* Add the address to the local list.  */
382                 addr = t_new(struct sctp_sockaddr_entry, GFP_ATOMIC);
383                 if (addr) {
384                         addr->a.v6.sin6_family = AF_INET6;
385                         addr->a.v6.sin6_port = 0;
386                         ipv6_addr_copy(&addr->a.v6.sin6_addr, &ifp->addr);
387                         addr->a.v6.sin6_scope_id = dev->ifindex;
388                         addr->valid = 1;
389                         INIT_LIST_HEAD(&addr->list);
390                         list_add_tail(&addr->list, addrlist);
391                 }
392         }
393
394         read_unlock_bh(&in6_dev->lock);
395         rcu_read_unlock();
396 }
397
398 /* Initialize a sockaddr_storage from in incoming skb. */
399 static void sctp_v6_from_skb(union sctp_addr *addr,struct sk_buff *skb,
400                              int is_saddr)
401 {
402         void *from;
403         __be16 *port;
404         struct sctphdr *sh;
405
406         port = &addr->v6.sin6_port;
407         addr->v6.sin6_family = AF_INET6;
408         addr->v6.sin6_flowinfo = 0; /* FIXME */
409         addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif;
410
411         sh = sctp_hdr(skb);
412         if (is_saddr) {
413                 *port  = sh->source;
414                 from = &ipv6_hdr(skb)->saddr;
415         } else {
416                 *port = sh->dest;
417                 from = &ipv6_hdr(skb)->daddr;
418         }
419         ipv6_addr_copy(&addr->v6.sin6_addr, from);
420 }
421
422 /* Initialize an sctp_addr from a socket. */
423 static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk)
424 {
425         addr->v6.sin6_family = AF_INET6;
426         addr->v6.sin6_port = 0;
427         ipv6_addr_copy(&addr->v6.sin6_addr, &inet6_sk(sk)->rcv_saddr);
428 }
429
430 /* Initialize sk->sk_rcv_saddr from sctp_addr. */
431 static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
432 {
433         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
434                 inet6_sk(sk)->rcv_saddr.s6_addr32[0] = 0;
435                 inet6_sk(sk)->rcv_saddr.s6_addr32[1] = 0;
436                 inet6_sk(sk)->rcv_saddr.s6_addr32[2] = htonl(0x0000ffff);
437                 inet6_sk(sk)->rcv_saddr.s6_addr32[3] =
438                         addr->v4.sin_addr.s_addr;
439         } else {
440                 ipv6_addr_copy(&inet6_sk(sk)->rcv_saddr, &addr->v6.sin6_addr);
441         }
442 }
443
444 /* Initialize sk->sk_daddr from sctp_addr. */
445 static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
446 {
447         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
448                 inet6_sk(sk)->daddr.s6_addr32[0] = 0;
449                 inet6_sk(sk)->daddr.s6_addr32[1] = 0;
450                 inet6_sk(sk)->daddr.s6_addr32[2] = htonl(0x0000ffff);
451                 inet6_sk(sk)->daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
452         } else {
453                 ipv6_addr_copy(&inet6_sk(sk)->daddr, &addr->v6.sin6_addr);
454         }
455 }
456
457 /* Initialize a sctp_addr from an address parameter. */
458 static void sctp_v6_from_addr_param(union sctp_addr *addr,
459                                     union sctp_addr_param *param,
460                                     __be16 port, int iif)
461 {
462         addr->v6.sin6_family = AF_INET6;
463         addr->v6.sin6_port = port;
464         addr->v6.sin6_flowinfo = 0; /* BUG */
465         ipv6_addr_copy(&addr->v6.sin6_addr, &param->v6.addr);
466         addr->v6.sin6_scope_id = iif;
467 }
468
469 /* Initialize an address parameter from a sctp_addr and return the length
470  * of the address parameter.
471  */
472 static int sctp_v6_to_addr_param(const union sctp_addr *addr,
473                                  union sctp_addr_param *param)
474 {
475         int length = sizeof(sctp_ipv6addr_param_t);
476
477         param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS;
478         param->v6.param_hdr.length = htons(length);
479         ipv6_addr_copy(&param->v6.addr, &addr->v6.sin6_addr);
480
481         return length;
482 }
483
484 /* Initialize a sctp_addr from struct in6_addr. */
485 static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr,
486                               __be16 port)
487 {
488         addr->sa.sa_family = AF_INET6;
489         addr->v6.sin6_port = port;
490         ipv6_addr_copy(&addr->v6.sin6_addr, saddr);
491 }
492
493 /* Compare addresses exactly.
494  * v4-mapped-v6 is also in consideration.
495  */
496 static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
497                             const union sctp_addr *addr2)
498 {
499         if (addr1->sa.sa_family != addr2->sa.sa_family) {
500                 if (addr1->sa.sa_family == AF_INET &&
501                     addr2->sa.sa_family == AF_INET6 &&
502                     ipv6_addr_v4mapped(&addr2->v6.sin6_addr)) {
503                         if (addr2->v6.sin6_port == addr1->v4.sin_port &&
504                             addr2->v6.sin6_addr.s6_addr32[3] ==
505                             addr1->v4.sin_addr.s_addr)
506                                 return 1;
507                 }
508                 if (addr2->sa.sa_family == AF_INET &&
509                     addr1->sa.sa_family == AF_INET6 &&
510                     ipv6_addr_v4mapped(&addr1->v6.sin6_addr)) {
511                         if (addr1->v6.sin6_port == addr2->v4.sin_port &&
512                             addr1->v6.sin6_addr.s6_addr32[3] ==
513                             addr2->v4.sin_addr.s_addr)
514                                 return 1;
515                 }
516                 return 0;
517         }
518         if (addr1->v6.sin6_port != addr2->v6.sin6_port)
519                 return 0;
520         if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))
521                 return 0;
522         /* If this is a linklocal address, compare the scope_id. */
523         if (ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) {
524                 if (addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&
525                     (addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)) {
526                         return 0;
527                 }
528         }
529
530         return 1;
531 }
532
533 /* Initialize addr struct to INADDR_ANY. */
534 static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port)
535 {
536         memset(addr, 0x00, sizeof(union sctp_addr));
537         addr->v6.sin6_family = AF_INET6;
538         addr->v6.sin6_port = port;
539 }
540
541 /* Is this a wildcard address? */
542 static int sctp_v6_is_any(const union sctp_addr *addr)
543 {
544         return ipv6_addr_any(&addr->v6.sin6_addr);
545 }
546
547 /* Should this be available for binding?   */
548 static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp)
549 {
550         int type;
551         const struct in6_addr *in6 = (const struct in6_addr *)&addr->v6.sin6_addr;
552
553         type = ipv6_addr_type(in6);
554         if (IPV6_ADDR_ANY == type)
555                 return 1;
556         if (type == IPV6_ADDR_MAPPED) {
557                 if (sp && !sp->v4mapped)
558                         return 0;
559                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
560                         return 0;
561                 sctp_v6_map_v4(addr);
562                 return sctp_get_af_specific(AF_INET)->available(addr, sp);
563         }
564         if (!(type & IPV6_ADDR_UNICAST))
565                 return 0;
566
567         return ipv6_chk_addr(&init_net, in6, NULL, 0);
568 }
569
570 /* This function checks if the address is a valid address to be used for
571  * SCTP.
572  *
573  * Output:
574  * Return 0 - If the address is a non-unicast or an illegal address.
575  * Return 1 - If the address is a unicast.
576  */
577 static int sctp_v6_addr_valid(union sctp_addr *addr,
578                               struct sctp_sock *sp,
579                               const struct sk_buff *skb)
580 {
581         int ret = ipv6_addr_type(&addr->v6.sin6_addr);
582
583         /* Support v4-mapped-v6 address. */
584         if (ret == IPV6_ADDR_MAPPED) {
585                 /* Note: This routine is used in input, so v4-mapped-v6
586                  * are disallowed here when there is no sctp_sock.
587                  */
588                 if (!sp || !sp->v4mapped)
589                         return 0;
590                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
591                         return 0;
592                 sctp_v6_map_v4(addr);
593                 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb);
594         }
595
596         /* Is this a non-unicast address */
597         if (!(ret & IPV6_ADDR_UNICAST))
598                 return 0;
599
600         return 1;
601 }
602
603 /* What is the scope of 'addr'?  */
604 static sctp_scope_t sctp_v6_scope(union sctp_addr *addr)
605 {
606         int v6scope;
607         sctp_scope_t retval;
608
609         /* The IPv6 scope is really a set of bit fields.
610          * See IFA_* in <net/if_inet6.h>.  Map to a generic SCTP scope.
611          */
612
613         v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
614         switch (v6scope) {
615         case IFA_HOST:
616                 retval = SCTP_SCOPE_LOOPBACK;
617                 break;
618         case IFA_LINK:
619                 retval = SCTP_SCOPE_LINK;
620                 break;
621         case IFA_SITE:
622                 retval = SCTP_SCOPE_PRIVATE;
623                 break;
624         default:
625                 retval = SCTP_SCOPE_GLOBAL;
626                 break;
627         }
628
629         return retval;
630 }
631
632 /* Create and initialize a new sk for the socket to be returned by accept(). */
633 static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
634                                              struct sctp_association *asoc)
635 {
636         struct sock *newsk;
637         struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
638         struct sctp6_sock *newsctp6sk;
639         struct ipv6_txoptions *opt;
640
641         newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot);
642         if (!newsk)
643                 goto out;
644
645         sock_init_data(NULL, newsk);
646
647         sctp_copy_sock(newsk, sk, asoc);
648         sock_reset_flag(sk, SOCK_ZAPPED);
649
650         newsctp6sk = (struct sctp6_sock *)newsk;
651         inet_sk(newsk)->pinet6 = &newsctp6sk->inet6;
652
653         sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped;
654
655         newnp = inet6_sk(newsk);
656
657         memcpy(newnp, np, sizeof(struct ipv6_pinfo));
658         newnp->ipv6_mc_list = NULL;
659         newnp->ipv6_ac_list = NULL;
660         newnp->ipv6_fl_list = NULL;
661
662         rcu_read_lock();
663         opt = rcu_dereference(np->opt);
664         if (opt)
665                 opt = ipv6_dup_options(newsk, opt);
666         RCU_INIT_POINTER(newnp->opt, opt);
667         rcu_read_unlock();
668
669         /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
670          * and getpeername().
671          */
672         sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
673
674         sk_refcnt_debug_inc(newsk);
675
676         if (newsk->sk_prot->init(newsk)) {
677                 sk_common_release(newsk);
678                 newsk = NULL;
679         }
680
681 out:
682         return newsk;
683 }
684
685 /* Map v4 address to mapped v6 address */
686 static void sctp_v6_addr_v4map(struct sctp_sock *sp, union sctp_addr *addr)
687 {
688         if (sp->v4mapped && AF_INET == addr->sa.sa_family)
689                 sctp_v4_map_v6(addr);
690 }
691
692 /* Where did this skb come from?  */
693 static int sctp_v6_skb_iif(const struct sk_buff *skb)
694 {
695         struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb;
696         return opt->iif;
697 }
698
699 /* Was this packet marked by Explicit Congestion Notification? */
700 static int sctp_v6_is_ce(const struct sk_buff *skb)
701 {
702         return *((__u32 *)(ipv6_hdr(skb))) & htonl(1 << 20);
703 }
704
705 /* Dump the v6 addr to the seq file. */
706 static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
707 {
708         seq_printf(seq, "%pI6 ", &addr->v6.sin6_addr);
709 }
710
711 static void sctp_v6_ecn_capable(struct sock *sk)
712 {
713         inet6_sk(sk)->tclass |= INET_ECN_ECT_0;
714 }
715
716 /* Initialize a PF_INET6 socket msg_name. */
717 static void sctp_inet6_msgname(char *msgname, int *addr_len)
718 {
719         struct sockaddr_in6 *sin6;
720
721         sin6 = (struct sockaddr_in6 *)msgname;
722         sin6->sin6_family = AF_INET6;
723         sin6->sin6_flowinfo = 0;
724         sin6->sin6_scope_id = 0; /*FIXME */
725         *addr_len = sizeof(struct sockaddr_in6);
726 }
727
728 /* Initialize a PF_INET msgname from a ulpevent. */
729 static void sctp_inet6_event_msgname(struct sctp_ulpevent *event,
730                                      char *msgname, int *addrlen)
731 {
732         struct sockaddr_in6 *sin6, *sin6from;
733
734         if (msgname) {
735                 union sctp_addr *addr;
736                 struct sctp_association *asoc;
737
738                 asoc = event->asoc;
739                 sctp_inet6_msgname(msgname, addrlen);
740                 sin6 = (struct sockaddr_in6 *)msgname;
741                 sin6->sin6_port = htons(asoc->peer.port);
742                 addr = &asoc->peer.primary_addr;
743
744                 /* Note: If we go to a common v6 format, this code
745                  * will change.
746                  */
747
748                 /* Map ipv4 address into v4-mapped-on-v6 address.  */
749                 if (sctp_sk(asoc->base.sk)->v4mapped &&
750                     AF_INET == addr->sa.sa_family) {
751                         sctp_v4_map_v6((union sctp_addr *)sin6);
752                         sin6->sin6_addr.s6_addr32[3] =
753                                 addr->v4.sin_addr.s_addr;
754                         return;
755                 }
756
757                 sin6from = &asoc->peer.primary_addr.v6;
758                 ipv6_addr_copy(&sin6->sin6_addr, &sin6from->sin6_addr);
759                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
760                         sin6->sin6_scope_id = sin6from->sin6_scope_id;
761         }
762 }
763
764 /* Initialize a msg_name from an inbound skb. */
765 static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname,
766                                    int *addr_len)
767 {
768         struct sctphdr *sh;
769         struct sockaddr_in6 *sin6;
770
771         if (msgname) {
772                 sctp_inet6_msgname(msgname, addr_len);
773                 sin6 = (struct sockaddr_in6 *)msgname;
774                 sh = sctp_hdr(skb);
775                 sin6->sin6_port = sh->source;
776
777                 /* Map ipv4 address into v4-mapped-on-v6 address. */
778                 if (sctp_sk(skb->sk)->v4mapped &&
779                     ip_hdr(skb)->version == 4) {
780                         sctp_v4_map_v6((union sctp_addr *)sin6);
781                         sin6->sin6_addr.s6_addr32[3] = ip_hdr(skb)->saddr;
782                         return;
783                 }
784
785                 /* Otherwise, just copy the v6 address. */
786                 ipv6_addr_copy(&sin6->sin6_addr, &ipv6_hdr(skb)->saddr);
787                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) {
788                         struct sctp_ulpevent *ev = sctp_skb2event(skb);
789                         sin6->sin6_scope_id = ev->iif;
790                 }
791         }
792 }
793
794 /* Do we support this AF? */
795 static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp)
796 {
797         switch (family) {
798         case AF_INET6:
799                 return 1;
800         /* v4-mapped-v6 addresses */
801         case AF_INET:
802                 if (!__ipv6_only_sock(sctp_opt2sk(sp)))
803                         return 1;
804         default:
805                 return 0;
806         }
807 }
808
809 /* Address matching with wildcards allowed.  This extra level
810  * of indirection lets us choose whether a PF_INET6 should
811  * disallow any v4 addresses if we so choose.
812  */
813 static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
814                                const union sctp_addr *addr2,
815                                struct sctp_sock *opt)
816 {
817         struct sctp_af *af1, *af2;
818         struct sock *sk = sctp_opt2sk(opt);
819
820         af1 = sctp_get_af_specific(addr1->sa.sa_family);
821         af2 = sctp_get_af_specific(addr2->sa.sa_family);
822
823         if (!af1 || !af2)
824                 return 0;
825
826         /* If the socket is IPv6 only, v4 addrs will not match */
827         if (__ipv6_only_sock(sk) && af1 != af2)
828                 return 0;
829
830         /* Today, wildcard AF_INET/AF_INET6. */
831         if (sctp_is_any(sk, addr1) || sctp_is_any(sk, addr2))
832                 return 1;
833
834         if (addr1->sa.sa_family != addr2->sa.sa_family)
835                 return 0;
836
837         return af1->cmp_addr(addr1, addr2);
838 }
839
840 /* Verify that the provided sockaddr looks bindable.   Common verification,
841  * has already been taken care of.
842  */
843 static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
844 {
845         struct sctp_af *af;
846
847         /* ASSERT: address family has already been verified. */
848         if (addr->sa.sa_family != AF_INET6)
849                 af = sctp_get_af_specific(addr->sa.sa_family);
850         else {
851                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
852                 struct net_device *dev;
853
854                 if (type & IPV6_ADDR_LINKLOCAL) {
855                         if (!addr->v6.sin6_scope_id)
856                                 return 0;
857                         rcu_read_lock();
858                         dev = dev_get_by_index_rcu(&init_net,
859                                                    addr->v6.sin6_scope_id);
860                         if (!dev ||
861                             !ipv6_chk_addr(&init_net, &addr->v6.sin6_addr,
862                                            dev, 0)) {
863                                 rcu_read_unlock();
864                                 return 0;
865                         }
866                         rcu_read_unlock();
867                 } else if (type == IPV6_ADDR_MAPPED) {
868                         if (!opt->v4mapped)
869                                 return 0;
870                 }
871
872                 af = opt->pf->af;
873         }
874         return af->available(addr, opt);
875 }
876
877 /* Verify that the provided sockaddr looks sendable.   Common verification,
878  * has already been taken care of.
879  */
880 static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
881 {
882         struct sctp_af *af = NULL;
883
884         /* ASSERT: address family has already been verified. */
885         if (addr->sa.sa_family != AF_INET6)
886                 af = sctp_get_af_specific(addr->sa.sa_family);
887         else {
888                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
889                 struct net_device *dev;
890
891                 if (type & IPV6_ADDR_LINKLOCAL) {
892                         if (!addr->v6.sin6_scope_id)
893                                 return 0;
894                         rcu_read_lock();
895                         dev = dev_get_by_index_rcu(&init_net,
896                                                    addr->v6.sin6_scope_id);
897                         rcu_read_unlock();
898                         if (!dev)
899                                 return 0;
900                 }
901                 af = opt->pf->af;
902         }
903
904         return af != NULL;
905 }
906
907 /* Fill in Supported Address Type information for INIT and INIT-ACK
908  * chunks.   Note: In the future, we may want to look at sock options
909  * to determine whether a PF_INET6 socket really wants to have IPV4
910  * addresses.
911  * Returns number of addresses supported.
912  */
913 static int sctp_inet6_supported_addrs(const struct sctp_sock *opt,
914                                       __be16 *types)
915 {
916         types[0] = SCTP_PARAM_IPV6_ADDRESS;
917         if (!opt || !ipv6_only_sock(sctp_opt2sk(opt))) {
918                 types[1] = SCTP_PARAM_IPV4_ADDRESS;
919                 return 2;
920         }
921         return 1;
922 }
923
924 static const struct proto_ops inet6_seqpacket_ops = {
925         .family            = PF_INET6,
926         .owner             = THIS_MODULE,
927         .release           = inet6_release,
928         .bind              = inet6_bind,
929         .connect           = inet_dgram_connect,
930         .socketpair        = sock_no_socketpair,
931         .accept            = inet_accept,
932         .getname           = inet6_getname,
933         .poll              = sctp_poll,
934         .ioctl             = inet6_ioctl,
935         .listen            = sctp_inet_listen,
936         .shutdown          = inet_shutdown,
937         .setsockopt        = sock_common_setsockopt,
938         .getsockopt        = sock_common_getsockopt,
939         .sendmsg           = inet_sendmsg,
940         .recvmsg           = sock_common_recvmsg,
941         .mmap              = sock_no_mmap,
942 #ifdef CONFIG_COMPAT
943         .compat_setsockopt = compat_sock_common_setsockopt,
944         .compat_getsockopt = compat_sock_common_getsockopt,
945 #endif
946 };
947
948 static struct inet_protosw sctpv6_seqpacket_protosw = {
949         .type          = SOCK_SEQPACKET,
950         .protocol      = IPPROTO_SCTP,
951         .prot          = &sctpv6_prot,
952         .ops           = &inet6_seqpacket_ops,
953         .no_check      = 0,
954         .flags         = SCTP_PROTOSW_FLAG
955 };
956 static struct inet_protosw sctpv6_stream_protosw = {
957         .type          = SOCK_STREAM,
958         .protocol      = IPPROTO_SCTP,
959         .prot          = &sctpv6_prot,
960         .ops           = &inet6_seqpacket_ops,
961         .no_check      = 0,
962         .flags         = SCTP_PROTOSW_FLAG,
963 };
964
965 static int sctp6_rcv(struct sk_buff *skb)
966 {
967         return sctp_rcv(skb) ? -1 : 0;
968 }
969
970 static const struct inet6_protocol sctpv6_protocol = {
971         .handler      = sctp6_rcv,
972         .err_handler  = sctp_v6_err,
973         .flags        = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
974 };
975
976 static struct sctp_af sctp_af_inet6 = {
977         .sa_family         = AF_INET6,
978         .sctp_xmit         = sctp_v6_xmit,
979         .setsockopt        = ipv6_setsockopt,
980         .getsockopt        = ipv6_getsockopt,
981         .get_dst           = sctp_v6_get_dst,
982         .get_saddr         = sctp_v6_get_saddr,
983         .copy_addrlist     = sctp_v6_copy_addrlist,
984         .from_skb          = sctp_v6_from_skb,
985         .from_sk           = sctp_v6_from_sk,
986         .to_sk_saddr       = sctp_v6_to_sk_saddr,
987         .to_sk_daddr       = sctp_v6_to_sk_daddr,
988         .from_addr_param   = sctp_v6_from_addr_param,
989         .to_addr_param     = sctp_v6_to_addr_param,
990         .cmp_addr          = sctp_v6_cmp_addr,
991         .scope             = sctp_v6_scope,
992         .addr_valid        = sctp_v6_addr_valid,
993         .inaddr_any        = sctp_v6_inaddr_any,
994         .is_any            = sctp_v6_is_any,
995         .available         = sctp_v6_available,
996         .skb_iif           = sctp_v6_skb_iif,
997         .is_ce             = sctp_v6_is_ce,
998         .seq_dump_addr     = sctp_v6_seq_dump_addr,
999         .ecn_capable       = sctp_v6_ecn_capable,
1000         .net_header_len    = sizeof(struct ipv6hdr),
1001         .sockaddr_len      = sizeof(struct sockaddr_in6),
1002 #ifdef CONFIG_COMPAT
1003         .compat_setsockopt = compat_ipv6_setsockopt,
1004         .compat_getsockopt = compat_ipv6_getsockopt,
1005 #endif
1006 };
1007
1008 static struct sctp_pf sctp_pf_inet6 = {
1009         .event_msgname = sctp_inet6_event_msgname,
1010         .skb_msgname   = sctp_inet6_skb_msgname,
1011         .af_supported  = sctp_inet6_af_supported,
1012         .cmp_addr      = sctp_inet6_cmp_addr,
1013         .bind_verify   = sctp_inet6_bind_verify,
1014         .send_verify   = sctp_inet6_send_verify,
1015         .supported_addrs = sctp_inet6_supported_addrs,
1016         .create_accept_sk = sctp_v6_create_accept_sk,
1017         .addr_v4map    = sctp_v6_addr_v4map,
1018         .af            = &sctp_af_inet6,
1019 };
1020
1021 /* Initialize IPv6 support and register with socket layer.  */
1022 void sctp_v6_pf_init(void)
1023 {
1024         /* Register the SCTP specific PF_INET6 functions. */
1025         sctp_register_pf(&sctp_pf_inet6, PF_INET6);
1026
1027         /* Register the SCTP specific AF_INET6 functions. */
1028         sctp_register_af(&sctp_af_inet6);
1029 }
1030
1031 void sctp_v6_pf_exit(void)
1032 {
1033         list_del(&sctp_af_inet6.list);
1034 }
1035
1036 /* Initialize IPv6 support and register with socket layer.  */
1037 int sctp_v6_protosw_init(void)
1038 {
1039         int rc;
1040
1041         rc = proto_register(&sctpv6_prot, 1);
1042         if (rc)
1043                 return rc;
1044
1045         /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
1046         inet6_register_protosw(&sctpv6_seqpacket_protosw);
1047         inet6_register_protosw(&sctpv6_stream_protosw);
1048
1049         return 0;
1050 }
1051
1052 void sctp_v6_protosw_exit(void)
1053 {
1054         inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
1055         inet6_unregister_protosw(&sctpv6_stream_protosw);
1056         proto_unregister(&sctpv6_prot);
1057 }
1058
1059
1060 /* Register with inet6 layer. */
1061 int sctp_v6_add_protocol(void)
1062 {
1063         /* Register notifier for inet6 address additions/deletions. */
1064         register_inet6addr_notifier(&sctp_inet6addr_notifier);
1065
1066         if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
1067                 return -EAGAIN;
1068
1069         return 0;
1070 }
1071
1072 /* Unregister with inet6 layer. */
1073 void sctp_v6_del_protocol(void)
1074 {
1075         inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
1076         unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
1077 }