4124bbb9994774cc6536cd1dd8f092202ca68d6e
[linux-2.6.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 #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/in.h>
57 #include <linux/in6.h>
58 #include <linux/netdevice.h>
59 #include <linux/init.h>
60 #include <linux/ipsec.h>
61
62 #include <linux/ipv6.h>
63 #include <linux/icmpv6.h>
64 #include <linux/random.h>
65 #include <linux/seq_file.h>
66
67 #include <net/protocol.h>
68 #include <net/ndisc.h>
69 #include <net/ip.h>
70 #include <net/ipv6.h>
71 #include <net/transp_v6.h>
72 #include <net/addrconf.h>
73 #include <net/ip6_route.h>
74 #include <net/inet_common.h>
75 #include <net/inet_ecn.h>
76 #include <net/sctp/sctp.h>
77
78 #include <asm/uaccess.h>
79
80 /* Event handler for inet6 address addition/deletion events.
81  * The sctp_local_addr_list needs to be protocted by a spin lock since
82  * multiple notifiers (say IPv4 and IPv6) may be running at the same
83  * time and thus corrupt the list.
84  * The reader side is protected with RCU.
85  */
86 static int sctp_inet6addr_event(struct notifier_block *this, unsigned long ev,
87                                 void *ptr)
88 {
89         struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
90         struct sctp_sockaddr_entry *addr = NULL;
91         struct sctp_sockaddr_entry *temp;
92         int found = 0;
93
94         switch (ev) {
95         case NETDEV_UP:
96                 addr = kmalloc(sizeof(struct sctp_sockaddr_entry), GFP_ATOMIC);
97                 if (addr) {
98                         addr->a.v6.sin6_family = AF_INET6;
99                         addr->a.v6.sin6_port = 0;
100                         memcpy(&addr->a.v6.sin6_addr, &ifa->addr,
101                                  sizeof(struct in6_addr));
102                         addr->a.v6.sin6_scope_id = ifa->idev->dev->ifindex;
103                         addr->valid = 1;
104                         spin_lock_bh(&sctp_local_addr_lock);
105                         list_add_tail_rcu(&addr->list, &sctp_local_addr_list);
106                         spin_unlock_bh(&sctp_local_addr_lock);
107                 }
108                 break;
109         case NETDEV_DOWN:
110                 spin_lock_bh(&sctp_local_addr_lock);
111                 list_for_each_entry_safe(addr, temp,
112                                         &sctp_local_addr_list, list) {
113                         if (addr->a.sa.sa_family == AF_INET6 &&
114                                         ipv6_addr_equal(&addr->a.v6.sin6_addr,
115                                                 &ifa->addr)) {
116                                 found = 1;
117                                 addr->valid = 0;
118                                 list_del_rcu(&addr->list);
119                                 break;
120                         }
121                 }
122                 spin_unlock_bh(&sctp_local_addr_lock);
123                 if (found)
124                         call_rcu(&addr->rcu, sctp_local_addr_free);
125                 break;
126         }
127
128         return NOTIFY_DONE;
129 }
130
131 static struct notifier_block sctp_inet6addr_notifier = {
132         .notifier_call = sctp_inet6addr_event,
133 };
134
135 /* ICMP error handler. */
136 SCTP_STATIC void sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
137                              int type, int code, int offset, __be32 info)
138 {
139         struct inet6_dev *idev;
140         struct sock *sk;
141         struct sctp_association *asoc;
142         struct sctp_transport *transport;
143         struct ipv6_pinfo *np;
144         sk_buff_data_t saveip, savesctp;
145         int err;
146
147         idev = in6_dev_get(skb->dev);
148
149         /* Fix up skb to look at the embedded net header. */
150         saveip   = skb->network_header;
151         savesctp = skb->transport_header;
152         skb_reset_network_header(skb);
153         skb_set_transport_header(skb, offset);
154         sk = sctp_err_lookup(AF_INET6, skb, sctp_hdr(skb), &asoc, &transport);
155         /* Put back, the original pointers. */
156         skb->network_header   = saveip;
157         skb->transport_header = savesctp;
158         if (!sk) {
159                 ICMP6_INC_STATS_BH(dev_net(skb->dev), idev, ICMP6_MIB_INERRORS);
160                 goto out;
161         }
162
163         /* Warning:  The sock lock is held.  Remember to call
164          * sctp_err_finish!
165          */
166
167         switch (type) {
168         case ICMPV6_PKT_TOOBIG:
169                 sctp_icmp_frag_needed(sk, asoc, transport, ntohl(info));
170                 goto out_unlock;
171         case ICMPV6_PARAMPROB:
172                 if (ICMPV6_UNK_NEXTHDR == code) {
173                         sctp_icmp_proto_unreachable(sk, asoc, transport);
174                         goto out_unlock;
175                 }
176                 break;
177         default:
178                 break;
179         }
180
181         np = inet6_sk(sk);
182         icmpv6_err_convert(type, code, &err);
183         if (!sock_owned_by_user(sk) && np->recverr) {
184                 sk->sk_err = err;
185                 sk->sk_error_report(sk);
186         } else {  /* Only an error on timeout */
187                 sk->sk_err_soft = err;
188         }
189
190 out_unlock:
191         sctp_err_finish(sk, asoc);
192 out:
193         if (likely(idev != NULL))
194                 in6_dev_put(idev);
195 }
196
197 /* Based on tcp_v6_xmit() in tcp_ipv6.c. */
198 static int sctp_v6_xmit(struct sk_buff *skb, struct sctp_transport *transport)
199 {
200         struct sock *sk = skb->sk;
201         struct ipv6_pinfo *np = inet6_sk(sk);
202         struct flowi fl;
203
204         memset(&fl, 0, sizeof(fl));
205
206         fl.proto = sk->sk_protocol;
207
208         /* Fill in the dest address from the route entry passed with the skb
209          * and the source address from the transport.
210          */
211         ipv6_addr_copy(&fl.fl6_dst, &transport->ipaddr.v6.sin6_addr);
212         ipv6_addr_copy(&fl.fl6_src, &transport->saddr.v6.sin6_addr);
213
214         fl.fl6_flowlabel = np->flow_label;
215         IP6_ECN_flow_xmit(sk, fl.fl6_flowlabel);
216         if (ipv6_addr_type(&fl.fl6_src) & IPV6_ADDR_LINKLOCAL)
217                 fl.oif = transport->saddr.v6.sin6_scope_id;
218         else
219                 fl.oif = sk->sk_bound_dev_if;
220
221         if (np->opt && np->opt->srcrt) {
222                 struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt;
223                 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
224         }
225
226         SCTP_DEBUG_PRINTK("%s: skb:%p, len:%d, "
227                           "src:" NIP6_FMT " dst:" NIP6_FMT "\n",
228                           __func__, skb, skb->len,
229                           NIP6(fl.fl6_src), NIP6(fl.fl6_dst));
230
231         SCTP_INC_STATS(SCTP_MIB_OUTSCTPPACKS);
232
233         if (!(transport->param_flags & SPP_PMTUD_ENABLE))
234                 skb->local_df = 1;
235
236         return ip6_xmit(sk, skb, &fl, np->opt, 0);
237 }
238
239 /* Returns the dst cache entry for the given source and destination ip
240  * addresses.
241  */
242 static struct dst_entry *sctp_v6_get_dst(struct sctp_association *asoc,
243                                          union sctp_addr *daddr,
244                                          union sctp_addr *saddr)
245 {
246         struct dst_entry *dst;
247         struct flowi fl;
248
249         memset(&fl, 0, sizeof(fl));
250         ipv6_addr_copy(&fl.fl6_dst, &daddr->v6.sin6_addr);
251         if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
252                 fl.oif = daddr->v6.sin6_scope_id;
253
254
255         SCTP_DEBUG_PRINTK("%s: DST=" NIP6_FMT " ",
256                           __func__, NIP6(fl.fl6_dst));
257
258         if (saddr) {
259                 ipv6_addr_copy(&fl.fl6_src, &saddr->v6.sin6_addr);
260                 SCTP_DEBUG_PRINTK(
261                         "SRC=" NIP6_FMT " - ",
262                         NIP6(fl.fl6_src));
263         }
264
265         dst = ip6_route_output(&init_net, NULL, &fl);
266         if (!dst->error) {
267                 struct rt6_info *rt;
268                 rt = (struct rt6_info *)dst;
269                 SCTP_DEBUG_PRINTK(
270                         "rt6_dst:" NIP6_FMT " rt6_src:" NIP6_FMT "\n",
271                         NIP6(rt->rt6i_dst.addr), NIP6(rt->rt6i_src.addr));
272                 return dst;
273         }
274         SCTP_DEBUG_PRINTK("NO ROUTE\n");
275         dst_release(dst);
276         return NULL;
277 }
278
279 /* Returns the number of consecutive initial bits that match in the 2 ipv6
280  * addresses.
281  */
282 static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
283                                          union sctp_addr *s2)
284 {
285         struct in6_addr *a1 = &s1->v6.sin6_addr;
286         struct in6_addr *a2 = &s2->v6.sin6_addr;
287         int i, j;
288
289         for (i = 0; i < 4 ; i++) {
290                 __be32 a1xora2;
291
292                 a1xora2 = a1->s6_addr32[i] ^ a2->s6_addr32[i];
293
294                 if ((j = fls(ntohl(a1xora2))))
295                         return (i * 32 + 32 - j);
296         }
297
298         return (i*32);
299 }
300
301 /* Fills in the source address(saddr) based on the destination address(daddr)
302  * and asoc's bind address list.
303  */
304 static void sctp_v6_get_saddr(struct sctp_sock *sk,
305                               struct sctp_association *asoc,
306                               struct dst_entry *dst,
307                               union sctp_addr *daddr,
308                               union sctp_addr *saddr)
309 {
310         struct sctp_bind_addr *bp;
311         struct sctp_sockaddr_entry *laddr;
312         sctp_scope_t scope;
313         union sctp_addr *baddr = NULL;
314         __u8 matchlen = 0;
315         __u8 bmatchlen;
316
317         SCTP_DEBUG_PRINTK("%s: asoc:%p dst:%p "
318                           "daddr:" NIP6_FMT " ",
319                           __func__, asoc, dst, NIP6(daddr->v6.sin6_addr));
320
321         if (!asoc) {
322                 ipv6_dev_get_saddr(sock_net(sctp_opt2sk(sk)),
323                                    dst ? ip6_dst_idev(dst)->dev : NULL,
324                                    &daddr->v6.sin6_addr,
325                                    inet6_sk(&sk->inet.sk)->srcprefs,
326                                    &saddr->v6.sin6_addr);
327                 SCTP_DEBUG_PRINTK("saddr from ipv6_get_saddr: " NIP6_FMT "\n",
328                                   NIP6(saddr->v6.sin6_addr));
329                 return;
330         }
331
332         scope = sctp_scope(daddr);
333
334         bp = &asoc->base.bind_addr;
335
336         /* Go through the bind address list and find the best source address
337          * that matches the scope of the destination address.
338          */
339         rcu_read_lock();
340         list_for_each_entry_rcu(laddr, &bp->address_list, list) {
341                 if (!laddr->valid)
342                         continue;
343                 if ((laddr->state == SCTP_ADDR_SRC) &&
344                     (laddr->a.sa.sa_family == AF_INET6) &&
345                     (scope <= sctp_scope(&laddr->a))) {
346                         bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a);
347                         if (!baddr || (matchlen < bmatchlen)) {
348                                 baddr = &laddr->a;
349                                 matchlen = bmatchlen;
350                         }
351                 }
352         }
353
354         if (baddr) {
355                 memcpy(saddr, baddr, sizeof(union sctp_addr));
356                 SCTP_DEBUG_PRINTK("saddr: " NIP6_FMT "\n",
357                                   NIP6(saddr->v6.sin6_addr));
358         } else {
359                 printk(KERN_ERR "%s: asoc:%p Could not find a valid source "
360                        "address for the dest:" NIP6_FMT "\n",
361                        __func__, asoc, NIP6(daddr->v6.sin6_addr));
362         }
363
364         rcu_read_unlock();
365 }
366
367 /* Make a copy of all potential local addresses. */
368 static void sctp_v6_copy_addrlist(struct list_head *addrlist,
369                                   struct net_device *dev)
370 {
371         struct inet6_dev *in6_dev;
372         struct inet6_ifaddr *ifp;
373         struct sctp_sockaddr_entry *addr;
374
375         rcu_read_lock();
376         if ((in6_dev = __in6_dev_get(dev)) == NULL) {
377                 rcu_read_unlock();
378                 return;
379         }
380
381         read_lock_bh(&in6_dev->lock);
382         for (ifp = in6_dev->addr_list; ifp; ifp = ifp->if_next) {
383                 /* Add the address to the local list.  */
384                 addr = t_new(struct sctp_sockaddr_entry, GFP_ATOMIC);
385                 if (addr) {
386                         addr->a.v6.sin6_family = AF_INET6;
387                         addr->a.v6.sin6_port = 0;
388                         addr->a.v6.sin6_addr = ifp->addr;
389                         addr->a.v6.sin6_scope_id = dev->ifindex;
390                         addr->valid = 1;
391                         INIT_LIST_HEAD(&addr->list);
392                         INIT_RCU_HEAD(&addr->rcu);
393                         list_add_tail(&addr->list, addrlist);
394                 }
395         }
396
397         read_unlock_bh(&in6_dev->lock);
398         rcu_read_unlock();
399 }
400
401 /* Initialize a sockaddr_storage from in incoming skb. */
402 static void sctp_v6_from_skb(union sctp_addr *addr,struct sk_buff *skb,
403                              int is_saddr)
404 {
405         void *from;
406         __be16 *port;
407         struct sctphdr *sh;
408
409         port = &addr->v6.sin6_port;
410         addr->v6.sin6_family = AF_INET6;
411         addr->v6.sin6_flowinfo = 0; /* FIXME */
412         addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif;
413
414         sh = sctp_hdr(skb);
415         if (is_saddr) {
416                 *port  = sh->source;
417                 from = &ipv6_hdr(skb)->saddr;
418         } else {
419                 *port = sh->dest;
420                 from = &ipv6_hdr(skb)->daddr;
421         }
422         ipv6_addr_copy(&addr->v6.sin6_addr, from);
423 }
424
425 /* Initialize an sctp_addr from a socket. */
426 static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk)
427 {
428         addr->v6.sin6_family = AF_INET6;
429         addr->v6.sin6_port = 0;
430         addr->v6.sin6_addr = inet6_sk(sk)->rcv_saddr;
431 }
432
433 /* Initialize sk->sk_rcv_saddr from sctp_addr. */
434 static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
435 {
436         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
437                 inet6_sk(sk)->rcv_saddr.s6_addr32[0] = 0;
438                 inet6_sk(sk)->rcv_saddr.s6_addr32[1] = 0;
439                 inet6_sk(sk)->rcv_saddr.s6_addr32[2] = htonl(0x0000ffff);
440                 inet6_sk(sk)->rcv_saddr.s6_addr32[3] =
441                         addr->v4.sin_addr.s_addr;
442         } else {
443                 inet6_sk(sk)->rcv_saddr = addr->v6.sin6_addr;
444         }
445 }
446
447 /* Initialize sk->sk_daddr from sctp_addr. */
448 static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
449 {
450         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
451                 inet6_sk(sk)->daddr.s6_addr32[0] = 0;
452                 inet6_sk(sk)->daddr.s6_addr32[1] = 0;
453                 inet6_sk(sk)->daddr.s6_addr32[2] = htonl(0x0000ffff);
454                 inet6_sk(sk)->daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
455         } else {
456                 inet6_sk(sk)->daddr = addr->v6.sin6_addr;
457         }
458 }
459
460 /* Initialize a sctp_addr from an address parameter. */
461 static void sctp_v6_from_addr_param(union sctp_addr *addr,
462                                     union sctp_addr_param *param,
463                                     __be16 port, int iif)
464 {
465         addr->v6.sin6_family = AF_INET6;
466         addr->v6.sin6_port = port;
467         addr->v6.sin6_flowinfo = 0; /* BUG */
468         ipv6_addr_copy(&addr->v6.sin6_addr, &param->v6.addr);
469         addr->v6.sin6_scope_id = iif;
470 }
471
472 /* Initialize an address parameter from a sctp_addr and return the length
473  * of the address parameter.
474  */
475 static int sctp_v6_to_addr_param(const union sctp_addr *addr,
476                                  union sctp_addr_param *param)
477 {
478         int length = sizeof(sctp_ipv6addr_param_t);
479
480         param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS;
481         param->v6.param_hdr.length = htons(length);
482         ipv6_addr_copy(&param->v6.addr, &addr->v6.sin6_addr);
483
484         return length;
485 }
486
487 /* Initialize a sctp_addr from a dst_entry. */
488 static void sctp_v6_dst_saddr(union sctp_addr *addr, struct dst_entry *dst,
489                               __be16 port)
490 {
491         struct rt6_info *rt = (struct rt6_info *)dst;
492         addr->sa.sa_family = AF_INET6;
493         addr->v6.sin6_port = port;
494         ipv6_addr_copy(&addr->v6.sin6_addr, &rt->rt6i_src.addr);
495 }
496
497 /* Compare addresses exactly.
498  * v4-mapped-v6 is also in consideration.
499  */
500 static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
501                             const union sctp_addr *addr2)
502 {
503         if (addr1->sa.sa_family != addr2->sa.sa_family) {
504                 if (addr1->sa.sa_family == AF_INET &&
505                     addr2->sa.sa_family == AF_INET6 &&
506                     ipv6_addr_v4mapped(&addr2->v6.sin6_addr)) {
507                         if (addr2->v6.sin6_port == addr1->v4.sin_port &&
508                             addr2->v6.sin6_addr.s6_addr32[3] ==
509                             addr1->v4.sin_addr.s_addr)
510                                 return 1;
511                 }
512                 if (addr2->sa.sa_family == AF_INET &&
513                     addr1->sa.sa_family == AF_INET6 &&
514                     ipv6_addr_v4mapped(&addr1->v6.sin6_addr)) {
515                         if (addr1->v6.sin6_port == addr2->v4.sin_port &&
516                             addr1->v6.sin6_addr.s6_addr32[3] ==
517                             addr2->v4.sin_addr.s_addr)
518                                 return 1;
519                 }
520                 return 0;
521         }
522         if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))
523                 return 0;
524         /* If this is a linklocal address, compare the scope_id. */
525         if (ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) {
526                 if (addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&
527                     (addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)) {
528                         return 0;
529                 }
530         }
531
532         return 1;
533 }
534
535 /* Initialize addr struct to INADDR_ANY. */
536 static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port)
537 {
538         memset(addr, 0x00, sizeof(union sctp_addr));
539         addr->v6.sin6_family = AF_INET6;
540         addr->v6.sin6_port = port;
541 }
542
543 /* Is this a wildcard address? */
544 static int sctp_v6_is_any(const union sctp_addr *addr)
545 {
546         return ipv6_addr_any(&addr->v6.sin6_addr);
547 }
548
549 /* Should this be available for binding?   */
550 static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp)
551 {
552         int type;
553         struct in6_addr *in6 = (struct in6_addr *)&addr->v6.sin6_addr;
554
555         type = ipv6_addr_type(in6);
556         if (IPV6_ADDR_ANY == type)
557                 return 1;
558         if (type == IPV6_ADDR_MAPPED) {
559                 if (sp && !sp->v4mapped)
560                         return 0;
561                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
562                         return 0;
563                 sctp_v6_map_v4(addr);
564                 return sctp_get_af_specific(AF_INET)->available(addr, sp);
565         }
566         if (!(type & IPV6_ADDR_UNICAST))
567                 return 0;
568
569         return ipv6_chk_addr(&init_net, in6, NULL, 0);
570 }
571
572 /* This function checks if the address is a valid address to be used for
573  * SCTP.
574  *
575  * Output:
576  * Return 0 - If the address is a non-unicast or an illegal address.
577  * Return 1 - If the address is a unicast.
578  */
579 static int sctp_v6_addr_valid(union sctp_addr *addr,
580                               struct sctp_sock *sp,
581                               const struct sk_buff *skb)
582 {
583         int ret = ipv6_addr_type(&addr->v6.sin6_addr);
584
585         /* Support v4-mapped-v6 address. */
586         if (ret == IPV6_ADDR_MAPPED) {
587                 /* Note: This routine is used in input, so v4-mapped-v6
588                  * are disallowed here when there is no sctp_sock.
589                  */
590                 if (!sp || !sp->v4mapped)
591                         return 0;
592                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
593                         return 0;
594                 sctp_v6_map_v4(addr);
595                 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb);
596         }
597
598         /* Is this a non-unicast address */
599         if (!(ret & IPV6_ADDR_UNICAST))
600                 return 0;
601
602         return 1;
603 }
604
605 /* What is the scope of 'addr'?  */
606 static sctp_scope_t sctp_v6_scope(union sctp_addr *addr)
607 {
608         int v6scope;
609         sctp_scope_t retval;
610
611         /* The IPv6 scope is really a set of bit fields.
612          * See IFA_* in <net/if_inet6.h>.  Map to a generic SCTP scope.
613          */
614
615         v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
616         switch (v6scope) {
617         case IFA_HOST:
618                 retval = SCTP_SCOPE_LOOPBACK;
619                 break;
620         case IFA_LINK:
621                 retval = SCTP_SCOPE_LINK;
622                 break;
623         case IFA_SITE:
624                 retval = SCTP_SCOPE_PRIVATE;
625                 break;
626         default:
627                 retval = SCTP_SCOPE_GLOBAL;
628                 break;
629         }
630
631         return retval;
632 }
633
634 /* Create and initialize a new sk for the socket to be returned by accept(). */
635 static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
636                                              struct sctp_association *asoc)
637 {
638         struct inet_sock *inet = inet_sk(sk);
639         struct sock *newsk;
640         struct inet_sock *newinet;
641         struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
642         struct sctp6_sock *newsctp6sk;
643
644         newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot);
645         if (!newsk)
646                 goto out;
647
648         sock_init_data(NULL, newsk);
649
650         newsk->sk_type = SOCK_STREAM;
651
652         newsk->sk_prot = sk->sk_prot;
653         newsk->sk_no_check = sk->sk_no_check;
654         newsk->sk_reuse = sk->sk_reuse;
655
656         newsk->sk_destruct = inet_sock_destruct;
657         newsk->sk_family = PF_INET6;
658         newsk->sk_protocol = IPPROTO_SCTP;
659         newsk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
660         newsk->sk_shutdown = sk->sk_shutdown;
661         sock_reset_flag(sk, SOCK_ZAPPED);
662
663         newsctp6sk = (struct sctp6_sock *)newsk;
664         inet_sk(newsk)->pinet6 = &newsctp6sk->inet6;
665
666         sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped;
667
668         newinet = inet_sk(newsk);
669         newnp = inet6_sk(newsk);
670
671         memcpy(newnp, np, sizeof(struct ipv6_pinfo));
672
673         /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
674          * and getpeername().
675          */
676         newinet->sport = inet->sport;
677         newnp->saddr = np->saddr;
678         newnp->rcv_saddr = np->rcv_saddr;
679         newinet->dport = htons(asoc->peer.port);
680         sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
681
682         /* Init the ipv4 part of the socket since we can have sockets
683          * using v6 API for ipv4.
684          */
685         newinet->uc_ttl = -1;
686         newinet->mc_loop = 1;
687         newinet->mc_ttl = 1;
688         newinet->mc_index = 0;
689         newinet->mc_list = NULL;
690
691         if (ipv4_config.no_pmtu_disc)
692                 newinet->pmtudisc = IP_PMTUDISC_DONT;
693         else
694                 newinet->pmtudisc = IP_PMTUDISC_WANT;
695
696         sk_refcnt_debug_inc(newsk);
697
698         if (newsk->sk_prot->init(newsk)) {
699                 sk_common_release(newsk);
700                 newsk = NULL;
701         }
702
703 out:
704         return newsk;
705 }
706
707 /* Map v4 address to mapped v6 address */
708 static void sctp_v6_addr_v4map(struct sctp_sock *sp, union sctp_addr *addr)
709 {
710         if (sp->v4mapped && AF_INET == addr->sa.sa_family)
711                 sctp_v4_map_v6(addr);
712 }
713
714 /* Where did this skb come from?  */
715 static int sctp_v6_skb_iif(const struct sk_buff *skb)
716 {
717         struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb;
718         return opt->iif;
719 }
720
721 /* Was this packet marked by Explicit Congestion Notification? */
722 static int sctp_v6_is_ce(const struct sk_buff *skb)
723 {
724         return *((__u32 *)(ipv6_hdr(skb))) & htonl(1 << 20);
725 }
726
727 /* Dump the v6 addr to the seq file. */
728 static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
729 {
730         seq_printf(seq, NIP6_FMT " ", NIP6(addr->v6.sin6_addr));
731 }
732
733 static void sctp_v6_ecn_capable(struct sock *sk)
734 {
735         inet6_sk(sk)->tclass |= INET_ECN_ECT_0;
736 }
737
738 /* Initialize a PF_INET6 socket msg_name. */
739 static void sctp_inet6_msgname(char *msgname, int *addr_len)
740 {
741         struct sockaddr_in6 *sin6;
742
743         sin6 = (struct sockaddr_in6 *)msgname;
744         sin6->sin6_family = AF_INET6;
745         sin6->sin6_flowinfo = 0;
746         sin6->sin6_scope_id = 0; /*FIXME */
747         *addr_len = sizeof(struct sockaddr_in6);
748 }
749
750 /* Initialize a PF_INET msgname from a ulpevent. */
751 static void sctp_inet6_event_msgname(struct sctp_ulpevent *event,
752                                      char *msgname, int *addrlen)
753 {
754         struct sockaddr_in6 *sin6, *sin6from;
755
756         if (msgname) {
757                 union sctp_addr *addr;
758                 struct sctp_association *asoc;
759
760                 asoc = event->asoc;
761                 sctp_inet6_msgname(msgname, addrlen);
762                 sin6 = (struct sockaddr_in6 *)msgname;
763                 sin6->sin6_port = htons(asoc->peer.port);
764                 addr = &asoc->peer.primary_addr;
765
766                 /* Note: If we go to a common v6 format, this code
767                  * will change.
768                  */
769
770                 /* Map ipv4 address into v4-mapped-on-v6 address.  */
771                 if (sctp_sk(asoc->base.sk)->v4mapped &&
772                     AF_INET == addr->sa.sa_family) {
773                         sctp_v4_map_v6((union sctp_addr *)sin6);
774                         sin6->sin6_addr.s6_addr32[3] =
775                                 addr->v4.sin_addr.s_addr;
776                         return;
777                 }
778
779                 sin6from = &asoc->peer.primary_addr.v6;
780                 ipv6_addr_copy(&sin6->sin6_addr, &sin6from->sin6_addr);
781                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
782                         sin6->sin6_scope_id = sin6from->sin6_scope_id;
783         }
784 }
785
786 /* Initialize a msg_name from an inbound skb. */
787 static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname,
788                                    int *addr_len)
789 {
790         struct sctphdr *sh;
791         struct sockaddr_in6 *sin6;
792
793         if (msgname) {
794                 sctp_inet6_msgname(msgname, addr_len);
795                 sin6 = (struct sockaddr_in6 *)msgname;
796                 sh = sctp_hdr(skb);
797                 sin6->sin6_port = sh->source;
798
799                 /* Map ipv4 address into v4-mapped-on-v6 address. */
800                 if (sctp_sk(skb->sk)->v4mapped &&
801                     ip_hdr(skb)->version == 4) {
802                         sctp_v4_map_v6((union sctp_addr *)sin6);
803                         sin6->sin6_addr.s6_addr32[3] = ip_hdr(skb)->saddr;
804                         return;
805                 }
806
807                 /* Otherwise, just copy the v6 address. */
808                 ipv6_addr_copy(&sin6->sin6_addr, &ipv6_hdr(skb)->saddr);
809                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) {
810                         struct sctp_ulpevent *ev = sctp_skb2event(skb);
811                         sin6->sin6_scope_id = ev->iif;
812                 }
813         }
814 }
815
816 /* Do we support this AF? */
817 static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp)
818 {
819         switch (family) {
820         case AF_INET6:
821                 return 1;
822         /* v4-mapped-v6 addresses */
823         case AF_INET:
824                 if (!__ipv6_only_sock(sctp_opt2sk(sp)))
825                         return 1;
826         default:
827                 return 0;
828         }
829 }
830
831 /* Address matching with wildcards allowed.  This extra level
832  * of indirection lets us choose whether a PF_INET6 should
833  * disallow any v4 addresses if we so choose.
834  */
835 static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
836                                const union sctp_addr *addr2,
837                                struct sctp_sock *opt)
838 {
839         struct sctp_af *af1, *af2;
840         struct sock *sk = sctp_opt2sk(opt);
841
842         af1 = sctp_get_af_specific(addr1->sa.sa_family);
843         af2 = sctp_get_af_specific(addr2->sa.sa_family);
844
845         if (!af1 || !af2)
846                 return 0;
847
848         /* If the socket is IPv6 only, v4 addrs will not match */
849         if (__ipv6_only_sock(sk) && af1 != af2)
850                 return 0;
851
852         /* Today, wildcard AF_INET/AF_INET6. */
853         if (sctp_is_any(sk, addr1) || sctp_is_any(sk, addr2))
854                 return 1;
855
856         if (addr1->sa.sa_family != addr2->sa.sa_family)
857                 return 0;
858
859         return af1->cmp_addr(addr1, addr2);
860 }
861
862 /* Verify that the provided sockaddr looks bindable.   Common verification,
863  * has already been taken care of.
864  */
865 static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
866 {
867         struct sctp_af *af;
868
869         /* ASSERT: address family has already been verified. */
870         if (addr->sa.sa_family != AF_INET6)
871                 af = sctp_get_af_specific(addr->sa.sa_family);
872         else {
873                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
874                 struct net_device *dev;
875
876                 if (type & IPV6_ADDR_LINKLOCAL) {
877                         if (!addr->v6.sin6_scope_id)
878                                 return 0;
879                         dev = dev_get_by_index(&init_net, addr->v6.sin6_scope_id);
880                         if (!dev)
881                                 return 0;
882                         if (!ipv6_chk_addr(&init_net, &addr->v6.sin6_addr,
883                                            dev, 0)) {
884                                 dev_put(dev);
885                                 return 0;
886                         }
887                         dev_put(dev);
888                 } else if (type == IPV6_ADDR_MAPPED) {
889                         if (!opt->v4mapped)
890                                 return 0;
891                 }
892
893                 af = opt->pf->af;
894         }
895         return af->available(addr, opt);
896 }
897
898 /* Verify that the provided sockaddr looks sendable.   Common verification,
899  * has already been taken care of.
900  */
901 static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
902 {
903         struct sctp_af *af = NULL;
904
905         /* ASSERT: address family has already been verified. */
906         if (addr->sa.sa_family != AF_INET6)
907                 af = sctp_get_af_specific(addr->sa.sa_family);
908         else {
909                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
910                 struct net_device *dev;
911
912                 if (type & IPV6_ADDR_LINKLOCAL) {
913                         if (!addr->v6.sin6_scope_id)
914                                 return 0;
915                         dev = dev_get_by_index(&init_net, addr->v6.sin6_scope_id);
916                         if (!dev)
917                                 return 0;
918                         dev_put(dev);
919                 }
920                 af = opt->pf->af;
921         }
922
923         return af != NULL;
924 }
925
926 /* Fill in Supported Address Type information for INIT and INIT-ACK
927  * chunks.   Note: In the future, we may want to look at sock options
928  * to determine whether a PF_INET6 socket really wants to have IPV4
929  * addresses.
930  * Returns number of addresses supported.
931  */
932 static int sctp_inet6_supported_addrs(const struct sctp_sock *opt,
933                                       __be16 *types)
934 {
935         types[0] = SCTP_PARAM_IPV6_ADDRESS;
936         if (!opt || !ipv6_only_sock(sctp_opt2sk(opt))) {
937                 types[1] = SCTP_PARAM_IPV4_ADDRESS;
938                 return 2;
939         }
940         return 1;
941 }
942
943 static const struct proto_ops inet6_seqpacket_ops = {
944         .family            = PF_INET6,
945         .owner             = THIS_MODULE,
946         .release           = inet6_release,
947         .bind              = inet6_bind,
948         .connect           = inet_dgram_connect,
949         .socketpair        = sock_no_socketpair,
950         .accept            = inet_accept,
951         .getname           = inet6_getname,
952         .poll              = sctp_poll,
953         .ioctl             = inet6_ioctl,
954         .listen            = sctp_inet_listen,
955         .shutdown          = inet_shutdown,
956         .setsockopt        = sock_common_setsockopt,
957         .getsockopt        = sock_common_getsockopt,
958         .sendmsg           = inet_sendmsg,
959         .recvmsg           = sock_common_recvmsg,
960         .mmap              = sock_no_mmap,
961 #ifdef CONFIG_COMPAT
962         .compat_setsockopt = compat_sock_common_setsockopt,
963         .compat_getsockopt = compat_sock_common_getsockopt,
964 #endif
965 };
966
967 static struct inet_protosw sctpv6_seqpacket_protosw = {
968         .type          = SOCK_SEQPACKET,
969         .protocol      = IPPROTO_SCTP,
970         .prot          = &sctpv6_prot,
971         .ops           = &inet6_seqpacket_ops,
972         .capability    = -1,
973         .no_check      = 0,
974         .flags         = SCTP_PROTOSW_FLAG
975 };
976 static struct inet_protosw sctpv6_stream_protosw = {
977         .type          = SOCK_STREAM,
978         .protocol      = IPPROTO_SCTP,
979         .prot          = &sctpv6_prot,
980         .ops           = &inet6_seqpacket_ops,
981         .capability    = -1,
982         .no_check      = 0,
983         .flags         = SCTP_PROTOSW_FLAG,
984 };
985
986 static int sctp6_rcv(struct sk_buff *skb)
987 {
988         return sctp_rcv(skb) ? -1 : 0;
989 }
990
991 static struct inet6_protocol sctpv6_protocol = {
992         .handler      = sctp6_rcv,
993         .err_handler  = sctp_v6_err,
994         .flags        = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
995 };
996
997 static struct sctp_af sctp_af_inet6 = {
998         .sa_family         = AF_INET6,
999         .sctp_xmit         = sctp_v6_xmit,
1000         .setsockopt        = ipv6_setsockopt,
1001         .getsockopt        = ipv6_getsockopt,
1002         .get_dst           = sctp_v6_get_dst,
1003         .get_saddr         = sctp_v6_get_saddr,
1004         .copy_addrlist     = sctp_v6_copy_addrlist,
1005         .from_skb          = sctp_v6_from_skb,
1006         .from_sk           = sctp_v6_from_sk,
1007         .to_sk_saddr       = sctp_v6_to_sk_saddr,
1008         .to_sk_daddr       = sctp_v6_to_sk_daddr,
1009         .from_addr_param   = sctp_v6_from_addr_param,
1010         .to_addr_param     = sctp_v6_to_addr_param,
1011         .dst_saddr         = sctp_v6_dst_saddr,
1012         .cmp_addr          = sctp_v6_cmp_addr,
1013         .scope             = sctp_v6_scope,
1014         .addr_valid        = sctp_v6_addr_valid,
1015         .inaddr_any        = sctp_v6_inaddr_any,
1016         .is_any            = sctp_v6_is_any,
1017         .available         = sctp_v6_available,
1018         .skb_iif           = sctp_v6_skb_iif,
1019         .is_ce             = sctp_v6_is_ce,
1020         .seq_dump_addr     = sctp_v6_seq_dump_addr,
1021         .ecn_capable       = sctp_v6_ecn_capable,
1022         .net_header_len    = sizeof(struct ipv6hdr),
1023         .sockaddr_len      = sizeof(struct sockaddr_in6),
1024 #ifdef CONFIG_COMPAT
1025         .compat_setsockopt = compat_ipv6_setsockopt,
1026         .compat_getsockopt = compat_ipv6_getsockopt,
1027 #endif
1028 };
1029
1030 static struct sctp_pf sctp_pf_inet6 = {
1031         .event_msgname = sctp_inet6_event_msgname,
1032         .skb_msgname   = sctp_inet6_skb_msgname,
1033         .af_supported  = sctp_inet6_af_supported,
1034         .cmp_addr      = sctp_inet6_cmp_addr,
1035         .bind_verify   = sctp_inet6_bind_verify,
1036         .send_verify   = sctp_inet6_send_verify,
1037         .supported_addrs = sctp_inet6_supported_addrs,
1038         .create_accept_sk = sctp_v6_create_accept_sk,
1039         .addr_v4map    = sctp_v6_addr_v4map,
1040         .af            = &sctp_af_inet6,
1041 };
1042
1043 /* Initialize IPv6 support and register with socket layer.  */
1044 void sctp_v6_pf_init(void)
1045 {
1046         /* Register the SCTP specific PF_INET6 functions. */
1047         sctp_register_pf(&sctp_pf_inet6, PF_INET6);
1048
1049         /* Register the SCTP specific AF_INET6 functions. */
1050         sctp_register_af(&sctp_af_inet6);
1051 }
1052
1053 void sctp_v6_pf_exit(void)
1054 {
1055         list_del(&sctp_af_inet6.list);
1056 }
1057
1058 /* Initialize IPv6 support and register with socket layer.  */
1059 int sctp_v6_protosw_init(void)
1060 {
1061         int rc;
1062
1063         rc = proto_register(&sctpv6_prot, 1);
1064         if (rc)
1065                 return rc;
1066
1067         /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
1068         inet6_register_protosw(&sctpv6_seqpacket_protosw);
1069         inet6_register_protosw(&sctpv6_stream_protosw);
1070
1071         return 0;
1072 }
1073
1074 void sctp_v6_protosw_exit(void)
1075 {
1076         inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
1077         inet6_unregister_protosw(&sctpv6_stream_protosw);
1078         proto_unregister(&sctpv6_prot);
1079 }
1080
1081
1082 /* Register with inet6 layer. */
1083 int sctp_v6_add_protocol(void)
1084 {
1085         /* Register notifier for inet6 address additions/deletions. */
1086         register_inet6addr_notifier(&sctp_inet6addr_notifier);
1087
1088         if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
1089                 return -EAGAIN;
1090
1091         return 0;
1092 }
1093
1094 /* Unregister with inet6 layer. */
1095 void sctp_v6_del_protocol(void)
1096 {
1097         inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
1098         unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
1099 }