Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
[linux-2.6] / 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(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                         int ipfragok)
200 {
201         struct sock *sk = skb->sk;
202         struct ipv6_pinfo *np = inet6_sk(sk);
203         struct flowi fl;
204
205         memset(&fl, 0, sizeof(fl));
206
207         fl.proto = sk->sk_protocol;
208
209         /* Fill in the dest address from the route entry passed with the skb
210          * and the source address from the transport.
211          */
212         ipv6_addr_copy(&fl.fl6_dst, &transport->ipaddr.v6.sin6_addr);
213         ipv6_addr_copy(&fl.fl6_src, &transport->saddr.v6.sin6_addr);
214
215         fl.fl6_flowlabel = np->flow_label;
216         IP6_ECN_flow_xmit(sk, fl.fl6_flowlabel);
217         if (ipv6_addr_type(&fl.fl6_src) & IPV6_ADDR_LINKLOCAL)
218                 fl.oif = transport->saddr.v6.sin6_scope_id;
219         else
220                 fl.oif = sk->sk_bound_dev_if;
221
222         if (np->opt && np->opt->srcrt) {
223                 struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt;
224                 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
225         }
226
227         SCTP_DEBUG_PRINTK("%s: skb:%p, len:%d, "
228                           "src:" NIP6_FMT " dst:" NIP6_FMT "\n",
229                           __func__, skb, skb->len,
230                           NIP6(fl.fl6_src), NIP6(fl.fl6_dst));
231
232         SCTP_INC_STATS(SCTP_MIB_OUTSCTPPACKS);
233
234         return ip6_xmit(sk, skb, &fl, np->opt, ipfragok);
235 }
236
237 /* Returns the dst cache entry for the given source and destination ip
238  * addresses.
239  */
240 static struct dst_entry *sctp_v6_get_dst(struct sctp_association *asoc,
241                                          union sctp_addr *daddr,
242                                          union sctp_addr *saddr)
243 {
244         struct dst_entry *dst;
245         struct flowi fl;
246
247         memset(&fl, 0, sizeof(fl));
248         ipv6_addr_copy(&fl.fl6_dst, &daddr->v6.sin6_addr);
249         if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
250                 fl.oif = daddr->v6.sin6_scope_id;
251
252
253         SCTP_DEBUG_PRINTK("%s: DST=" NIP6_FMT " ",
254                           __func__, NIP6(fl.fl6_dst));
255
256         if (saddr) {
257                 ipv6_addr_copy(&fl.fl6_src, &saddr->v6.sin6_addr);
258                 SCTP_DEBUG_PRINTK(
259                         "SRC=" NIP6_FMT " - ",
260                         NIP6(fl.fl6_src));
261         }
262
263         dst = ip6_route_output(&init_net, NULL, &fl);
264         if (!dst->error) {
265                 struct rt6_info *rt;
266                 rt = (struct rt6_info *)dst;
267                 SCTP_DEBUG_PRINTK(
268                         "rt6_dst:" NIP6_FMT " rt6_src:" NIP6_FMT "\n",
269                         NIP6(rt->rt6i_dst.addr), NIP6(rt->rt6i_src.addr));
270                 return dst;
271         }
272         SCTP_DEBUG_PRINTK("NO ROUTE\n");
273         dst_release(dst);
274         return NULL;
275 }
276
277 /* Returns the number of consecutive initial bits that match in the 2 ipv6
278  * addresses.
279  */
280 static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
281                                          union sctp_addr *s2)
282 {
283         struct in6_addr *a1 = &s1->v6.sin6_addr;
284         struct in6_addr *a2 = &s2->v6.sin6_addr;
285         int i, j;
286
287         for (i = 0; i < 4 ; i++) {
288                 __be32 a1xora2;
289
290                 a1xora2 = a1->s6_addr32[i] ^ a2->s6_addr32[i];
291
292                 if ((j = fls(ntohl(a1xora2))))
293                         return (i * 32 + 32 - j);
294         }
295
296         return (i*32);
297 }
298
299 /* Fills in the source address(saddr) based on the destination address(daddr)
300  * and asoc's bind address list.
301  */
302 static void sctp_v6_get_saddr(struct sctp_association *asoc,
303                               struct dst_entry *dst,
304                               union sctp_addr *daddr,
305                               union sctp_addr *saddr)
306 {
307         struct sctp_bind_addr *bp;
308         struct sctp_sockaddr_entry *laddr;
309         sctp_scope_t scope;
310         union sctp_addr *baddr = NULL;
311         __u8 matchlen = 0;
312         __u8 bmatchlen;
313
314         SCTP_DEBUG_PRINTK("%s: asoc:%p dst:%p "
315                           "daddr:" NIP6_FMT " ",
316                           __func__, asoc, dst, NIP6(daddr->v6.sin6_addr));
317
318         if (!asoc) {
319                 ipv6_dev_get_saddr(dst ? ip6_dst_idev(dst)->dev : NULL,
320                                    &daddr->v6.sin6_addr,
321                                    inet6_sk(asoc->base.sk)->srcprefs,
322                                    &saddr->v6.sin6_addr);
323                 SCTP_DEBUG_PRINTK("saddr from ipv6_get_saddr: " NIP6_FMT "\n",
324                                   NIP6(saddr->v6.sin6_addr));
325                 return;
326         }
327
328         scope = sctp_scope(daddr);
329
330         bp = &asoc->base.bind_addr;
331
332         /* Go through the bind address list and find the best source address
333          * that matches the scope of the destination address.
334          */
335         rcu_read_lock();
336         list_for_each_entry_rcu(laddr, &bp->address_list, list) {
337                 if (!laddr->valid)
338                         continue;
339                 if ((laddr->state == SCTP_ADDR_SRC) &&
340                     (laddr->a.sa.sa_family == AF_INET6) &&
341                     (scope <= sctp_scope(&laddr->a))) {
342                         bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a);
343                         if (!baddr || (matchlen < bmatchlen)) {
344                                 baddr = &laddr->a;
345                                 matchlen = bmatchlen;
346                         }
347                 }
348         }
349
350         if (baddr) {
351                 memcpy(saddr, baddr, sizeof(union sctp_addr));
352                 SCTP_DEBUG_PRINTK("saddr: " NIP6_FMT "\n",
353                                   NIP6(saddr->v6.sin6_addr));
354         } else {
355                 printk(KERN_ERR "%s: asoc:%p Could not find a valid source "
356                        "address for the dest:" NIP6_FMT "\n",
357                        __func__, asoc, NIP6(daddr->v6.sin6_addr));
358         }
359
360         rcu_read_unlock();
361 }
362
363 /* Make a copy of all potential local addresses. */
364 static void sctp_v6_copy_addrlist(struct list_head *addrlist,
365                                   struct net_device *dev)
366 {
367         struct inet6_dev *in6_dev;
368         struct inet6_ifaddr *ifp;
369         struct sctp_sockaddr_entry *addr;
370
371         rcu_read_lock();
372         if ((in6_dev = __in6_dev_get(dev)) == NULL) {
373                 rcu_read_unlock();
374                 return;
375         }
376
377         read_lock_bh(&in6_dev->lock);
378         for (ifp = in6_dev->addr_list; ifp; ifp = ifp->if_next) {
379                 /* Add the address to the local list.  */
380                 addr = t_new(struct sctp_sockaddr_entry, GFP_ATOMIC);
381                 if (addr) {
382                         addr->a.v6.sin6_family = AF_INET6;
383                         addr->a.v6.sin6_port = 0;
384                         addr->a.v6.sin6_addr = ifp->addr;
385                         addr->a.v6.sin6_scope_id = dev->ifindex;
386                         addr->valid = 1;
387                         INIT_LIST_HEAD(&addr->list);
388                         INIT_RCU_HEAD(&addr->rcu);
389                         list_add_tail(&addr->list, addrlist);
390                 }
391         }
392
393         read_unlock_bh(&in6_dev->lock);
394         rcu_read_unlock();
395 }
396
397 /* Initialize a sockaddr_storage from in incoming skb. */
398 static void sctp_v6_from_skb(union sctp_addr *addr,struct sk_buff *skb,
399                              int is_saddr)
400 {
401         void *from;
402         __be16 *port;
403         struct sctphdr *sh;
404
405         port = &addr->v6.sin6_port;
406         addr->v6.sin6_family = AF_INET6;
407         addr->v6.sin6_flowinfo = 0; /* FIXME */
408         addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif;
409
410         sh = sctp_hdr(skb);
411         if (is_saddr) {
412                 *port  = sh->source;
413                 from = &ipv6_hdr(skb)->saddr;
414         } else {
415                 *port = sh->dest;
416                 from = &ipv6_hdr(skb)->daddr;
417         }
418         ipv6_addr_copy(&addr->v6.sin6_addr, from);
419 }
420
421 /* Initialize an sctp_addr from a socket. */
422 static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk)
423 {
424         addr->v6.sin6_family = AF_INET6;
425         addr->v6.sin6_port = 0;
426         addr->v6.sin6_addr = inet6_sk(sk)->rcv_saddr;
427 }
428
429 /* Initialize sk->sk_rcv_saddr from sctp_addr. */
430 static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
431 {
432         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
433                 inet6_sk(sk)->rcv_saddr.s6_addr32[0] = 0;
434                 inet6_sk(sk)->rcv_saddr.s6_addr32[1] = 0;
435                 inet6_sk(sk)->rcv_saddr.s6_addr32[2] = htonl(0x0000ffff);
436                 inet6_sk(sk)->rcv_saddr.s6_addr32[3] =
437                         addr->v4.sin_addr.s_addr;
438         } else {
439                 inet6_sk(sk)->rcv_saddr = addr->v6.sin6_addr;
440         }
441 }
442
443 /* Initialize sk->sk_daddr from sctp_addr. */
444 static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
445 {
446         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
447                 inet6_sk(sk)->daddr.s6_addr32[0] = 0;
448                 inet6_sk(sk)->daddr.s6_addr32[1] = 0;
449                 inet6_sk(sk)->daddr.s6_addr32[2] = htonl(0x0000ffff);
450                 inet6_sk(sk)->daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
451         } else {
452                 inet6_sk(sk)->daddr = addr->v6.sin6_addr;
453         }
454 }
455
456 /* Initialize a sctp_addr from an address parameter. */
457 static void sctp_v6_from_addr_param(union sctp_addr *addr,
458                                     union sctp_addr_param *param,
459                                     __be16 port, int iif)
460 {
461         addr->v6.sin6_family = AF_INET6;
462         addr->v6.sin6_port = port;
463         addr->v6.sin6_flowinfo = 0; /* BUG */
464         ipv6_addr_copy(&addr->v6.sin6_addr, &param->v6.addr);
465         addr->v6.sin6_scope_id = iif;
466 }
467
468 /* Initialize an address parameter from a sctp_addr and return the length
469  * of the address parameter.
470  */
471 static int sctp_v6_to_addr_param(const union sctp_addr *addr,
472                                  union sctp_addr_param *param)
473 {
474         int length = sizeof(sctp_ipv6addr_param_t);
475
476         param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS;
477         param->v6.param_hdr.length = htons(length);
478         ipv6_addr_copy(&param->v6.addr, &addr->v6.sin6_addr);
479
480         return length;
481 }
482
483 /* Initialize a sctp_addr from a dst_entry. */
484 static void sctp_v6_dst_saddr(union sctp_addr *addr, struct dst_entry *dst,
485                               __be16 port)
486 {
487         struct rt6_info *rt = (struct rt6_info *)dst;
488         addr->sa.sa_family = AF_INET6;
489         addr->v6.sin6_port = port;
490         ipv6_addr_copy(&addr->v6.sin6_addr, &rt->rt6i_src.addr);
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 (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))
519                 return 0;
520         /* If this is a linklocal address, compare the scope_id. */
521         if (ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) {
522                 if (addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&
523                     (addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)) {
524                         return 0;
525                 }
526         }
527
528         return 1;
529 }
530
531 /* Initialize addr struct to INADDR_ANY. */
532 static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port)
533 {
534         memset(addr, 0x00, sizeof(union sctp_addr));
535         addr->v6.sin6_family = AF_INET6;
536         addr->v6.sin6_port = port;
537 }
538
539 /* Is this a wildcard address? */
540 static int sctp_v6_is_any(const union sctp_addr *addr)
541 {
542         return ipv6_addr_any(&addr->v6.sin6_addr);
543 }
544
545 /* Should this be available for binding?   */
546 static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp)
547 {
548         int type;
549         struct in6_addr *in6 = (struct in6_addr *)&addr->v6.sin6_addr;
550
551         type = ipv6_addr_type(in6);
552         if (IPV6_ADDR_ANY == type)
553                 return 1;
554         if (type == IPV6_ADDR_MAPPED) {
555                 if (sp && !sp->v4mapped)
556                         return 0;
557                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
558                         return 0;
559                 sctp_v6_map_v4(addr);
560                 return sctp_get_af_specific(AF_INET)->available(addr, sp);
561         }
562         if (!(type & IPV6_ADDR_UNICAST))
563                 return 0;
564
565         return ipv6_chk_addr(&init_net, in6, NULL, 0);
566 }
567
568 /* This function checks if the address is a valid address to be used for
569  * SCTP.
570  *
571  * Output:
572  * Return 0 - If the address is a non-unicast or an illegal address.
573  * Return 1 - If the address is a unicast.
574  */
575 static int sctp_v6_addr_valid(union sctp_addr *addr,
576                               struct sctp_sock *sp,
577                               const struct sk_buff *skb)
578 {
579         int ret = ipv6_addr_type(&addr->v6.sin6_addr);
580
581         /* Support v4-mapped-v6 address. */
582         if (ret == IPV6_ADDR_MAPPED) {
583                 /* Note: This routine is used in input, so v4-mapped-v6
584                  * are disallowed here when there is no sctp_sock.
585                  */
586                 if (!sp || !sp->v4mapped)
587                         return 0;
588                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
589                         return 0;
590                 sctp_v6_map_v4(addr);
591                 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb);
592         }
593
594         /* Is this a non-unicast address */
595         if (!(ret & IPV6_ADDR_UNICAST))
596                 return 0;
597
598         return 1;
599 }
600
601 /* What is the scope of 'addr'?  */
602 static sctp_scope_t sctp_v6_scope(union sctp_addr *addr)
603 {
604         int v6scope;
605         sctp_scope_t retval;
606
607         /* The IPv6 scope is really a set of bit fields.
608          * See IFA_* in <net/if_inet6.h>.  Map to a generic SCTP scope.
609          */
610
611         v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
612         switch (v6scope) {
613         case IFA_HOST:
614                 retval = SCTP_SCOPE_LOOPBACK;
615                 break;
616         case IFA_LINK:
617                 retval = SCTP_SCOPE_LINK;
618                 break;
619         case IFA_SITE:
620                 retval = SCTP_SCOPE_PRIVATE;
621                 break;
622         default:
623                 retval = SCTP_SCOPE_GLOBAL;
624                 break;
625         }
626
627         return retval;
628 }
629
630 /* Create and initialize a new sk for the socket to be returned by accept(). */
631 static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
632                                              struct sctp_association *asoc)
633 {
634         struct inet_sock *inet = inet_sk(sk);
635         struct sock *newsk;
636         struct inet_sock *newinet;
637         struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
638         struct sctp6_sock *newsctp6sk;
639
640         newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot);
641         if (!newsk)
642                 goto out;
643
644         sock_init_data(NULL, newsk);
645
646         newsk->sk_type = SOCK_STREAM;
647
648         newsk->sk_prot = sk->sk_prot;
649         newsk->sk_no_check = sk->sk_no_check;
650         newsk->sk_reuse = sk->sk_reuse;
651
652         newsk->sk_destruct = inet_sock_destruct;
653         newsk->sk_family = PF_INET6;
654         newsk->sk_protocol = IPPROTO_SCTP;
655         newsk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
656         newsk->sk_shutdown = sk->sk_shutdown;
657         sock_reset_flag(sk, SOCK_ZAPPED);
658
659         newsctp6sk = (struct sctp6_sock *)newsk;
660         inet_sk(newsk)->pinet6 = &newsctp6sk->inet6;
661
662         sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped;
663
664         newinet = inet_sk(newsk);
665         newnp = inet6_sk(newsk);
666
667         memcpy(newnp, np, sizeof(struct ipv6_pinfo));
668
669         /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
670          * and getpeername().
671          */
672         newinet->sport = inet->sport;
673         newnp->saddr = np->saddr;
674         newnp->rcv_saddr = np->rcv_saddr;
675         newinet->dport = htons(asoc->peer.port);
676         sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
677
678         /* Init the ipv4 part of the socket since we can have sockets
679          * using v6 API for ipv4.
680          */
681         newinet->uc_ttl = -1;
682         newinet->mc_loop = 1;
683         newinet->mc_ttl = 1;
684         newinet->mc_index = 0;
685         newinet->mc_list = NULL;
686
687         if (ipv4_config.no_pmtu_disc)
688                 newinet->pmtudisc = IP_PMTUDISC_DONT;
689         else
690                 newinet->pmtudisc = IP_PMTUDISC_WANT;
691
692         sk_refcnt_debug_inc(newsk);
693
694         if (newsk->sk_prot->init(newsk)) {
695                 sk_common_release(newsk);
696                 newsk = NULL;
697         }
698
699 out:
700         return newsk;
701 }
702
703 /* Map v4 address to mapped v6 address */
704 static void sctp_v6_addr_v4map(struct sctp_sock *sp, union sctp_addr *addr)
705 {
706         if (sp->v4mapped && AF_INET == addr->sa.sa_family)
707                 sctp_v4_map_v6(addr);
708 }
709
710 /* Where did this skb come from?  */
711 static int sctp_v6_skb_iif(const struct sk_buff *skb)
712 {
713         struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb;
714         return opt->iif;
715 }
716
717 /* Was this packet marked by Explicit Congestion Notification? */
718 static int sctp_v6_is_ce(const struct sk_buff *skb)
719 {
720         return *((__u32 *)(ipv6_hdr(skb))) & htonl(1 << 20);
721 }
722
723 /* Dump the v6 addr to the seq file. */
724 static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
725 {
726         seq_printf(seq, NIP6_FMT " ", NIP6(addr->v6.sin6_addr));
727 }
728
729 /* Initialize a PF_INET6 socket msg_name. */
730 static void sctp_inet6_msgname(char *msgname, int *addr_len)
731 {
732         struct sockaddr_in6 *sin6;
733
734         sin6 = (struct sockaddr_in6 *)msgname;
735         sin6->sin6_family = AF_INET6;
736         sin6->sin6_flowinfo = 0;
737         sin6->sin6_scope_id = 0; /*FIXME */
738         *addr_len = sizeof(struct sockaddr_in6);
739 }
740
741 /* Initialize a PF_INET msgname from a ulpevent. */
742 static void sctp_inet6_event_msgname(struct sctp_ulpevent *event,
743                                      char *msgname, int *addrlen)
744 {
745         struct sockaddr_in6 *sin6, *sin6from;
746
747         if (msgname) {
748                 union sctp_addr *addr;
749                 struct sctp_association *asoc;
750
751                 asoc = event->asoc;
752                 sctp_inet6_msgname(msgname, addrlen);
753                 sin6 = (struct sockaddr_in6 *)msgname;
754                 sin6->sin6_port = htons(asoc->peer.port);
755                 addr = &asoc->peer.primary_addr;
756
757                 /* Note: If we go to a common v6 format, this code
758                  * will change.
759                  */
760
761                 /* Map ipv4 address into v4-mapped-on-v6 address.  */
762                 if (sctp_sk(asoc->base.sk)->v4mapped &&
763                     AF_INET == addr->sa.sa_family) {
764                         sctp_v4_map_v6((union sctp_addr *)sin6);
765                         sin6->sin6_addr.s6_addr32[3] =
766                                 addr->v4.sin_addr.s_addr;
767                         return;
768                 }
769
770                 sin6from = &asoc->peer.primary_addr.v6;
771                 ipv6_addr_copy(&sin6->sin6_addr, &sin6from->sin6_addr);
772                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
773                         sin6->sin6_scope_id = sin6from->sin6_scope_id;
774         }
775 }
776
777 /* Initialize a msg_name from an inbound skb. */
778 static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname,
779                                    int *addr_len)
780 {
781         struct sctphdr *sh;
782         struct sockaddr_in6 *sin6;
783
784         if (msgname) {
785                 sctp_inet6_msgname(msgname, addr_len);
786                 sin6 = (struct sockaddr_in6 *)msgname;
787                 sh = sctp_hdr(skb);
788                 sin6->sin6_port = sh->source;
789
790                 /* Map ipv4 address into v4-mapped-on-v6 address. */
791                 if (sctp_sk(skb->sk)->v4mapped &&
792                     ip_hdr(skb)->version == 4) {
793                         sctp_v4_map_v6((union sctp_addr *)sin6);
794                         sin6->sin6_addr.s6_addr32[3] = ip_hdr(skb)->saddr;
795                         return;
796                 }
797
798                 /* Otherwise, just copy the v6 address. */
799                 ipv6_addr_copy(&sin6->sin6_addr, &ipv6_hdr(skb)->saddr);
800                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) {
801                         struct sctp_ulpevent *ev = sctp_skb2event(skb);
802                         sin6->sin6_scope_id = ev->iif;
803                 }
804         }
805 }
806
807 /* Do we support this AF? */
808 static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp)
809 {
810         switch (family) {
811         case AF_INET6:
812                 return 1;
813         /* v4-mapped-v6 addresses */
814         case AF_INET:
815                 if (!__ipv6_only_sock(sctp_opt2sk(sp)) && sp->v4mapped)
816                         return 1;
817         default:
818                 return 0;
819         }
820 }
821
822 /* Address matching with wildcards allowed.  This extra level
823  * of indirection lets us choose whether a PF_INET6 should
824  * disallow any v4 addresses if we so choose.
825  */
826 static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
827                                const union sctp_addr *addr2,
828                                struct sctp_sock *opt)
829 {
830         struct sctp_af *af1, *af2;
831
832         af1 = sctp_get_af_specific(addr1->sa.sa_family);
833         af2 = sctp_get_af_specific(addr2->sa.sa_family);
834
835         if (!af1 || !af2)
836                 return 0;
837         /* Today, wildcard AF_INET/AF_INET6. */
838         if (sctp_is_any(addr1) || sctp_is_any(addr2))
839                 return 1;
840
841         if (addr1->sa.sa_family != addr2->sa.sa_family)
842                 return 0;
843
844         return af1->cmp_addr(addr1, addr2);
845 }
846
847 /* Verify that the provided sockaddr looks bindable.   Common verification,
848  * has already been taken care of.
849  */
850 static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
851 {
852         struct sctp_af *af;
853
854         /* ASSERT: address family has already been verified. */
855         if (addr->sa.sa_family != AF_INET6)
856                 af = sctp_get_af_specific(addr->sa.sa_family);
857         else {
858                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
859                 struct net_device *dev;
860
861                 if (type & IPV6_ADDR_LINKLOCAL) {
862                         if (!addr->v6.sin6_scope_id)
863                                 return 0;
864                         dev = dev_get_by_index(&init_net, addr->v6.sin6_scope_id);
865                         if (!dev)
866                                 return 0;
867                         if (!ipv6_chk_addr(&init_net, &addr->v6.sin6_addr,
868                                            dev, 0)) {
869                                 dev_put(dev);
870                                 return 0;
871                         }
872                         dev_put(dev);
873                 }
874                 af = opt->pf->af;
875         }
876         return af->available(addr, opt);
877 }
878
879 /* Verify that the provided sockaddr looks sendable.   Common verification,
880  * has already been taken care of.
881  */
882 static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
883 {
884         struct sctp_af *af = NULL;
885
886         /* ASSERT: address family has already been verified. */
887         if (addr->sa.sa_family != AF_INET6)
888                 af = sctp_get_af_specific(addr->sa.sa_family);
889         else {
890                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
891                 struct net_device *dev;
892
893                 if (type & IPV6_ADDR_LINKLOCAL) {
894                         if (!addr->v6.sin6_scope_id)
895                                 return 0;
896                         dev = dev_get_by_index(&init_net, addr->v6.sin6_scope_id);
897                         if (!dev)
898                                 return 0;
899                         dev_put(dev);
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_IPV4_ADDRESS;
917         types[1] = SCTP_PARAM_IPV6_ADDRESS;
918         return 2;
919 }
920
921 static const struct proto_ops inet6_seqpacket_ops = {
922         .family            = PF_INET6,
923         .owner             = THIS_MODULE,
924         .release           = inet6_release,
925         .bind              = inet6_bind,
926         .connect           = inet_dgram_connect,
927         .socketpair        = sock_no_socketpair,
928         .accept            = inet_accept,
929         .getname           = inet6_getname,
930         .poll              = sctp_poll,
931         .ioctl             = inet6_ioctl,
932         .listen            = sctp_inet_listen,
933         .shutdown          = inet_shutdown,
934         .setsockopt        = sock_common_setsockopt,
935         .getsockopt        = sock_common_getsockopt,
936         .sendmsg           = inet_sendmsg,
937         .recvmsg           = sock_common_recvmsg,
938         .mmap              = sock_no_mmap,
939 #ifdef CONFIG_COMPAT
940         .compat_setsockopt = compat_sock_common_setsockopt,
941         .compat_getsockopt = compat_sock_common_getsockopt,
942 #endif
943 };
944
945 static struct inet_protosw sctpv6_seqpacket_protosw = {
946         .type          = SOCK_SEQPACKET,
947         .protocol      = IPPROTO_SCTP,
948         .prot          = &sctpv6_prot,
949         .ops           = &inet6_seqpacket_ops,
950         .capability    = -1,
951         .no_check      = 0,
952         .flags         = SCTP_PROTOSW_FLAG
953 };
954 static struct inet_protosw sctpv6_stream_protosw = {
955         .type          = SOCK_STREAM,
956         .protocol      = IPPROTO_SCTP,
957         .prot          = &sctpv6_prot,
958         .ops           = &inet6_seqpacket_ops,
959         .capability    = -1,
960         .no_check      = 0,
961         .flags         = SCTP_PROTOSW_FLAG,
962 };
963
964 static int sctp6_rcv(struct sk_buff *skb)
965 {
966         return sctp_rcv(skb) ? -1 : 0;
967 }
968
969 static struct inet6_protocol sctpv6_protocol = {
970         .handler      = sctp6_rcv,
971         .err_handler  = sctp_v6_err,
972         .flags        = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
973 };
974
975 static struct sctp_af sctp_af_inet6 = {
976         .sa_family         = AF_INET6,
977         .sctp_xmit         = sctp_v6_xmit,
978         .setsockopt        = ipv6_setsockopt,
979         .getsockopt        = ipv6_getsockopt,
980         .get_dst           = sctp_v6_get_dst,
981         .get_saddr         = sctp_v6_get_saddr,
982         .copy_addrlist     = sctp_v6_copy_addrlist,
983         .from_skb          = sctp_v6_from_skb,
984         .from_sk           = sctp_v6_from_sk,
985         .to_sk_saddr       = sctp_v6_to_sk_saddr,
986         .to_sk_daddr       = sctp_v6_to_sk_daddr,
987         .from_addr_param   = sctp_v6_from_addr_param,
988         .to_addr_param     = sctp_v6_to_addr_param,
989         .dst_saddr         = sctp_v6_dst_saddr,
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         .net_header_len    = sizeof(struct ipv6hdr),
1000         .sockaddr_len      = sizeof(struct sockaddr_in6),
1001 #ifdef CONFIG_COMPAT
1002         .compat_setsockopt = compat_ipv6_setsockopt,
1003         .compat_getsockopt = compat_ipv6_getsockopt,
1004 #endif
1005 };
1006
1007 static struct sctp_pf sctp_pf_inet6 = {
1008         .event_msgname = sctp_inet6_event_msgname,
1009         .skb_msgname   = sctp_inet6_skb_msgname,
1010         .af_supported  = sctp_inet6_af_supported,
1011         .cmp_addr      = sctp_inet6_cmp_addr,
1012         .bind_verify   = sctp_inet6_bind_verify,
1013         .send_verify   = sctp_inet6_send_verify,
1014         .supported_addrs = sctp_inet6_supported_addrs,
1015         .create_accept_sk = sctp_v6_create_accept_sk,
1016         .addr_v4map    = sctp_v6_addr_v4map,
1017         .af            = &sctp_af_inet6,
1018 };
1019
1020 /* Initialize IPv6 support and register with socket layer.  */
1021 void sctp_v6_pf_init(void)
1022 {
1023         /* Register the SCTP specific PF_INET6 functions. */
1024         sctp_register_pf(&sctp_pf_inet6, PF_INET6);
1025
1026         /* Register the SCTP specific AF_INET6 functions. */
1027         sctp_register_af(&sctp_af_inet6);
1028 }
1029
1030 void sctp_v6_pf_exit(void)
1031 {
1032         list_del(&sctp_af_inet6.list);
1033 }
1034
1035 /* Initialize IPv6 support and register with socket layer.  */
1036 int sctp_v6_protosw_init(void)
1037 {
1038         int rc;
1039
1040         rc = proto_register(&sctpv6_prot, 1);
1041         if (rc)
1042                 return rc;
1043
1044         /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
1045         inet6_register_protosw(&sctpv6_seqpacket_protosw);
1046         inet6_register_protosw(&sctpv6_stream_protosw);
1047
1048         return 0;
1049 }
1050
1051 void sctp_v6_protosw_exit(void)
1052 {
1053         inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
1054         inet6_unregister_protosw(&sctpv6_stream_protosw);
1055         proto_unregister(&sctpv6_prot);
1056 }
1057
1058
1059 /* Register with inet6 layer. */
1060 int sctp_v6_add_protocol(void)
1061 {
1062         /* Register notifier for inet6 address additions/deletions. */
1063         register_inet6addr_notifier(&sctp_inet6addr_notifier);
1064
1065         if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
1066                 return -EAGAIN;
1067
1068         return 0;
1069 }
1070
1071 /* Unregister with inet6 layer. */
1072 void sctp_v6_del_protocol(void)
1073 {
1074         inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
1075         unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
1076 }