net: replace remaining __FUNCTION__ occurrences
[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
93         switch (ev) {
94         case NETDEV_UP:
95                 addr = kmalloc(sizeof(struct sctp_sockaddr_entry), GFP_ATOMIC);
96                 if (addr) {
97                         addr->a.v6.sin6_family = AF_INET6;
98                         addr->a.v6.sin6_port = 0;
99                         memcpy(&addr->a.v6.sin6_addr, &ifa->addr,
100                                  sizeof(struct in6_addr));
101                         addr->a.v6.sin6_scope_id = ifa->idev->dev->ifindex;
102                         addr->valid = 1;
103                         spin_lock_bh(&sctp_local_addr_lock);
104                         list_add_tail_rcu(&addr->list, &sctp_local_addr_list);
105                         spin_unlock_bh(&sctp_local_addr_lock);
106                 }
107                 break;
108         case NETDEV_DOWN:
109                 spin_lock_bh(&sctp_local_addr_lock);
110                 list_for_each_entry_safe(addr, temp,
111                                         &sctp_local_addr_list, list) {
112                         if (ipv6_addr_equal(&addr->a.v6.sin6_addr,
113                                              &ifa->addr)) {
114                                 addr->valid = 0;
115                                 list_del_rcu(&addr->list);
116                                 break;
117                         }
118                 }
119                 spin_unlock_bh(&sctp_local_addr_lock);
120                 if (addr && !addr->valid)
121                         call_rcu(&addr->rcu, sctp_local_addr_free);
122                 break;
123         }
124
125         return NOTIFY_DONE;
126 }
127
128 static struct notifier_block sctp_inet6addr_notifier = {
129         .notifier_call = sctp_inet6addr_event,
130 };
131
132 /* ICMP error handler. */
133 SCTP_STATIC void sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
134                              int type, int code, int offset, __be32 info)
135 {
136         struct inet6_dev *idev;
137         struct sock *sk;
138         struct sctp_association *asoc;
139         struct sctp_transport *transport;
140         struct ipv6_pinfo *np;
141         sk_buff_data_t saveip, savesctp;
142         int err;
143
144         idev = in6_dev_get(skb->dev);
145
146         /* Fix up skb to look at the embedded net header. */
147         saveip   = skb->network_header;
148         savesctp = skb->transport_header;
149         skb_reset_network_header(skb);
150         skb_set_transport_header(skb, offset);
151         sk = sctp_err_lookup(AF_INET6, skb, sctp_hdr(skb), &asoc, &transport);
152         /* Put back, the original pointers. */
153         skb->network_header   = saveip;
154         skb->transport_header = savesctp;
155         if (!sk) {
156                 ICMP6_INC_STATS_BH(idev, ICMP6_MIB_INERRORS);
157                 goto out;
158         }
159
160         /* Warning:  The sock lock is held.  Remember to call
161          * sctp_err_finish!
162          */
163
164         switch (type) {
165         case ICMPV6_PKT_TOOBIG:
166                 sctp_icmp_frag_needed(sk, asoc, transport, ntohl(info));
167                 goto out_unlock;
168         case ICMPV6_PARAMPROB:
169                 if (ICMPV6_UNK_NEXTHDR == code) {
170                         sctp_icmp_proto_unreachable(sk, asoc, transport);
171                         goto out_unlock;
172                 }
173                 break;
174         default:
175                 break;
176         }
177
178         np = inet6_sk(sk);
179         icmpv6_err_convert(type, code, &err);
180         if (!sock_owned_by_user(sk) && np->recverr) {
181                 sk->sk_err = err;
182                 sk->sk_error_report(sk);
183         } else {  /* Only an error on timeout */
184                 sk->sk_err_soft = err;
185         }
186
187 out_unlock:
188         sctp_err_finish(sk, asoc);
189 out:
190         if (likely(idev != NULL))
191                 in6_dev_put(idev);
192 }
193
194 /* Based on tcp_v6_xmit() in tcp_ipv6.c. */
195 static int sctp_v6_xmit(struct sk_buff *skb, struct sctp_transport *transport,
196                         int ipfragok)
197 {
198         struct sock *sk = skb->sk;
199         struct ipv6_pinfo *np = inet6_sk(sk);
200         struct flowi fl;
201
202         memset(&fl, 0, sizeof(fl));
203
204         fl.proto = sk->sk_protocol;
205
206         /* Fill in the dest address from the route entry passed with the skb
207          * and the source address from the transport.
208          */
209         ipv6_addr_copy(&fl.fl6_dst, &transport->ipaddr.v6.sin6_addr);
210         ipv6_addr_copy(&fl.fl6_src, &transport->saddr.v6.sin6_addr);
211
212         fl.fl6_flowlabel = np->flow_label;
213         IP6_ECN_flow_xmit(sk, fl.fl6_flowlabel);
214         if (ipv6_addr_type(&fl.fl6_src) & IPV6_ADDR_LINKLOCAL)
215                 fl.oif = transport->saddr.v6.sin6_scope_id;
216         else
217                 fl.oif = sk->sk_bound_dev_if;
218
219         if (np->opt && np->opt->srcrt) {
220                 struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt;
221                 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
222         }
223
224         SCTP_DEBUG_PRINTK("%s: skb:%p, len:%d, "
225                           "src:" NIP6_FMT " dst:" NIP6_FMT "\n",
226                           __func__, skb, skb->len,
227                           NIP6(fl.fl6_src), NIP6(fl.fl6_dst));
228
229         SCTP_INC_STATS(SCTP_MIB_OUTSCTPPACKS);
230
231         return ip6_xmit(sk, skb, &fl, np->opt, ipfragok);
232 }
233
234 /* Returns the dst cache entry for the given source and destination ip
235  * addresses.
236  */
237 static struct dst_entry *sctp_v6_get_dst(struct sctp_association *asoc,
238                                          union sctp_addr *daddr,
239                                          union sctp_addr *saddr)
240 {
241         struct dst_entry *dst;
242         struct flowi fl;
243
244         memset(&fl, 0, sizeof(fl));
245         ipv6_addr_copy(&fl.fl6_dst, &daddr->v6.sin6_addr);
246         if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
247                 fl.oif = daddr->v6.sin6_scope_id;
248
249
250         SCTP_DEBUG_PRINTK("%s: DST=" NIP6_FMT " ",
251                           __func__, NIP6(fl.fl6_dst));
252
253         if (saddr) {
254                 ipv6_addr_copy(&fl.fl6_src, &saddr->v6.sin6_addr);
255                 SCTP_DEBUG_PRINTK(
256                         "SRC=" NIP6_FMT " - ",
257                         NIP6(fl.fl6_src));
258         }
259
260         dst = ip6_route_output(&init_net, NULL, &fl);
261         if (!dst->error) {
262                 struct rt6_info *rt;
263                 rt = (struct rt6_info *)dst;
264                 SCTP_DEBUG_PRINTK(
265                         "rt6_dst:" NIP6_FMT " rt6_src:" NIP6_FMT "\n",
266                         NIP6(rt->rt6i_dst.addr), NIP6(rt->rt6i_src.addr));
267                 return dst;
268         }
269         SCTP_DEBUG_PRINTK("NO ROUTE\n");
270         dst_release(dst);
271         return NULL;
272 }
273
274 /* Returns the number of consecutive initial bits that match in the 2 ipv6
275  * addresses.
276  */
277 static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
278                                          union sctp_addr *s2)
279 {
280         struct in6_addr *a1 = &s1->v6.sin6_addr;
281         struct in6_addr *a2 = &s2->v6.sin6_addr;
282         int i, j;
283
284         for (i = 0; i < 4 ; i++) {
285                 __be32 a1xora2;
286
287                 a1xora2 = a1->s6_addr32[i] ^ a2->s6_addr32[i];
288
289                 if ((j = fls(ntohl(a1xora2))))
290                         return (i * 32 + 32 - j);
291         }
292
293         return (i*32);
294 }
295
296 /* Fills in the source address(saddr) based on the destination address(daddr)
297  * and asoc's bind address list.
298  */
299 static void sctp_v6_get_saddr(struct sctp_association *asoc,
300                               struct dst_entry *dst,
301                               union sctp_addr *daddr,
302                               union sctp_addr *saddr)
303 {
304         struct sctp_bind_addr *bp;
305         struct sctp_sockaddr_entry *laddr;
306         sctp_scope_t scope;
307         union sctp_addr *baddr = NULL;
308         __u8 matchlen = 0;
309         __u8 bmatchlen;
310
311         SCTP_DEBUG_PRINTK("%s: asoc:%p dst:%p "
312                           "daddr:" NIP6_FMT " ",
313                           __func__, asoc, dst, NIP6(daddr->v6.sin6_addr));
314
315         if (!asoc) {
316                 ipv6_dev_get_saddr(dst ? ip6_dst_idev(dst)->dev : NULL,
317                                    &daddr->v6.sin6_addr, &saddr->v6.sin6_addr);
318                 SCTP_DEBUG_PRINTK("saddr from ipv6_get_saddr: " NIP6_FMT "\n",
319                                   NIP6(saddr->v6.sin6_addr));
320                 return;
321         }
322
323         scope = sctp_scope(daddr);
324
325         bp = &asoc->base.bind_addr;
326
327         /* Go through the bind address list and find the best source address
328          * that matches the scope of the destination address.
329          */
330         rcu_read_lock();
331         list_for_each_entry_rcu(laddr, &bp->address_list, list) {
332                 if (!laddr->valid)
333                         continue;
334                 if ((laddr->state == SCTP_ADDR_SRC) &&
335                     (laddr->a.sa.sa_family == AF_INET6) &&
336                     (scope <= sctp_scope(&laddr->a))) {
337                         bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a);
338                         if (!baddr || (matchlen < bmatchlen)) {
339                                 baddr = &laddr->a;
340                                 matchlen = bmatchlen;
341                         }
342                 }
343         }
344
345         if (baddr) {
346                 memcpy(saddr, baddr, sizeof(union sctp_addr));
347                 SCTP_DEBUG_PRINTK("saddr: " NIP6_FMT "\n",
348                                   NIP6(saddr->v6.sin6_addr));
349         } else {
350                 printk(KERN_ERR "%s: asoc:%p Could not find a valid source "
351                        "address for the dest:" NIP6_FMT "\n",
352                        __func__, asoc, NIP6(daddr->v6.sin6_addr));
353         }
354
355         rcu_read_unlock();
356 }
357
358 /* Make a copy of all potential local addresses. */
359 static void sctp_v6_copy_addrlist(struct list_head *addrlist,
360                                   struct net_device *dev)
361 {
362         struct inet6_dev *in6_dev;
363         struct inet6_ifaddr *ifp;
364         struct sctp_sockaddr_entry *addr;
365
366         rcu_read_lock();
367         if ((in6_dev = __in6_dev_get(dev)) == NULL) {
368                 rcu_read_unlock();
369                 return;
370         }
371
372         read_lock_bh(&in6_dev->lock);
373         for (ifp = in6_dev->addr_list; ifp; ifp = ifp->if_next) {
374                 /* Add the address to the local list.  */
375                 addr = t_new(struct sctp_sockaddr_entry, GFP_ATOMIC);
376                 if (addr) {
377                         addr->a.v6.sin6_family = AF_INET6;
378                         addr->a.v6.sin6_port = 0;
379                         addr->a.v6.sin6_addr = ifp->addr;
380                         addr->a.v6.sin6_scope_id = dev->ifindex;
381                         addr->valid = 1;
382                         INIT_LIST_HEAD(&addr->list);
383                         INIT_RCU_HEAD(&addr->rcu);
384                         list_add_tail(&addr->list, addrlist);
385                 }
386         }
387
388         read_unlock_bh(&in6_dev->lock);
389         rcu_read_unlock();
390 }
391
392 /* Initialize a sockaddr_storage from in incoming skb. */
393 static void sctp_v6_from_skb(union sctp_addr *addr,struct sk_buff *skb,
394                              int is_saddr)
395 {
396         void *from;
397         __be16 *port;
398         struct sctphdr *sh;
399
400         port = &addr->v6.sin6_port;
401         addr->v6.sin6_family = AF_INET6;
402         addr->v6.sin6_flowinfo = 0; /* FIXME */
403         addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif;
404
405         sh = sctp_hdr(skb);
406         if (is_saddr) {
407                 *port  = sh->source;
408                 from = &ipv6_hdr(skb)->saddr;
409         } else {
410                 *port = sh->dest;
411                 from = &ipv6_hdr(skb)->daddr;
412         }
413         ipv6_addr_copy(&addr->v6.sin6_addr, from);
414 }
415
416 /* Initialize an sctp_addr from a socket. */
417 static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk)
418 {
419         addr->v6.sin6_family = AF_INET6;
420         addr->v6.sin6_port = 0;
421         addr->v6.sin6_addr = inet6_sk(sk)->rcv_saddr;
422 }
423
424 /* Initialize sk->sk_rcv_saddr from sctp_addr. */
425 static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
426 {
427         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
428                 inet6_sk(sk)->rcv_saddr.s6_addr32[0] = 0;
429                 inet6_sk(sk)->rcv_saddr.s6_addr32[1] = 0;
430                 inet6_sk(sk)->rcv_saddr.s6_addr32[2] = htonl(0x0000ffff);
431                 inet6_sk(sk)->rcv_saddr.s6_addr32[3] =
432                         addr->v4.sin_addr.s_addr;
433         } else {
434                 inet6_sk(sk)->rcv_saddr = addr->v6.sin6_addr;
435         }
436 }
437
438 /* Initialize sk->sk_daddr from sctp_addr. */
439 static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
440 {
441         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
442                 inet6_sk(sk)->daddr.s6_addr32[0] = 0;
443                 inet6_sk(sk)->daddr.s6_addr32[1] = 0;
444                 inet6_sk(sk)->daddr.s6_addr32[2] = htonl(0x0000ffff);
445                 inet6_sk(sk)->daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
446         } else {
447                 inet6_sk(sk)->daddr = addr->v6.sin6_addr;
448         }
449 }
450
451 /* Initialize a sctp_addr from an address parameter. */
452 static void sctp_v6_from_addr_param(union sctp_addr *addr,
453                                     union sctp_addr_param *param,
454                                     __be16 port, int iif)
455 {
456         addr->v6.sin6_family = AF_INET6;
457         addr->v6.sin6_port = port;
458         addr->v6.sin6_flowinfo = 0; /* BUG */
459         ipv6_addr_copy(&addr->v6.sin6_addr, &param->v6.addr);
460         addr->v6.sin6_scope_id = iif;
461 }
462
463 /* Initialize an address parameter from a sctp_addr and return the length
464  * of the address parameter.
465  */
466 static int sctp_v6_to_addr_param(const union sctp_addr *addr,
467                                  union sctp_addr_param *param)
468 {
469         int length = sizeof(sctp_ipv6addr_param_t);
470
471         param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS;
472         param->v6.param_hdr.length = htons(length);
473         ipv6_addr_copy(&param->v6.addr, &addr->v6.sin6_addr);
474
475         return length;
476 }
477
478 /* Initialize a sctp_addr from a dst_entry. */
479 static void sctp_v6_dst_saddr(union sctp_addr *addr, struct dst_entry *dst,
480                               __be16 port)
481 {
482         struct rt6_info *rt = (struct rt6_info *)dst;
483         addr->sa.sa_family = AF_INET6;
484         addr->v6.sin6_port = port;
485         ipv6_addr_copy(&addr->v6.sin6_addr, &rt->rt6i_src.addr);
486 }
487
488 /* Compare addresses exactly.
489  * v4-mapped-v6 is also in consideration.
490  */
491 static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
492                             const union sctp_addr *addr2)
493 {
494         if (addr1->sa.sa_family != addr2->sa.sa_family) {
495                 if (addr1->sa.sa_family == AF_INET &&
496                     addr2->sa.sa_family == AF_INET6 &&
497                     ipv6_addr_v4mapped(&addr2->v6.sin6_addr)) {
498                         if (addr2->v6.sin6_port == addr1->v4.sin_port &&
499                             addr2->v6.sin6_addr.s6_addr32[3] ==
500                             addr1->v4.sin_addr.s_addr)
501                                 return 1;
502                 }
503                 if (addr2->sa.sa_family == AF_INET &&
504                     addr1->sa.sa_family == AF_INET6 &&
505                     ipv6_addr_v4mapped(&addr1->v6.sin6_addr)) {
506                         if (addr1->v6.sin6_port == addr2->v4.sin_port &&
507                             addr1->v6.sin6_addr.s6_addr32[3] ==
508                             addr2->v4.sin_addr.s_addr)
509                                 return 1;
510                 }
511                 return 0;
512         }
513         if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))
514                 return 0;
515         /* If this is a linklocal address, compare the scope_id. */
516         if (ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) {
517                 if (addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&
518                     (addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)) {
519                         return 0;
520                 }
521         }
522
523         return 1;
524 }
525
526 /* Initialize addr struct to INADDR_ANY. */
527 static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port)
528 {
529         memset(addr, 0x00, sizeof(union sctp_addr));
530         addr->v6.sin6_family = AF_INET6;
531         addr->v6.sin6_port = port;
532 }
533
534 /* Is this a wildcard address? */
535 static int sctp_v6_is_any(const union sctp_addr *addr)
536 {
537         return ipv6_addr_any(&addr->v6.sin6_addr);
538 }
539
540 /* Should this be available for binding?   */
541 static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp)
542 {
543         int type;
544         struct in6_addr *in6 = (struct in6_addr *)&addr->v6.sin6_addr;
545
546         type = ipv6_addr_type(in6);
547         if (IPV6_ADDR_ANY == type)
548                 return 1;
549         if (type == IPV6_ADDR_MAPPED) {
550                 if (sp && !sp->v4mapped)
551                         return 0;
552                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
553                         return 0;
554                 sctp_v6_map_v4(addr);
555                 return sctp_get_af_specific(AF_INET)->available(addr, sp);
556         }
557         if (!(type & IPV6_ADDR_UNICAST))
558                 return 0;
559
560         return ipv6_chk_addr(&init_net, in6, NULL, 0);
561 }
562
563 /* This function checks if the address is a valid address to be used for
564  * SCTP.
565  *
566  * Output:
567  * Return 0 - If the address is a non-unicast or an illegal address.
568  * Return 1 - If the address is a unicast.
569  */
570 static int sctp_v6_addr_valid(union sctp_addr *addr,
571                               struct sctp_sock *sp,
572                               const struct sk_buff *skb)
573 {
574         int ret = ipv6_addr_type(&addr->v6.sin6_addr);
575
576         /* Support v4-mapped-v6 address. */
577         if (ret == IPV6_ADDR_MAPPED) {
578                 /* Note: This routine is used in input, so v4-mapped-v6
579                  * are disallowed here when there is no sctp_sock.
580                  */
581                 if (!sp || !sp->v4mapped)
582                         return 0;
583                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
584                         return 0;
585                 sctp_v6_map_v4(addr);
586                 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb);
587         }
588
589         /* Is this a non-unicast address */
590         if (!(ret & IPV6_ADDR_UNICAST))
591                 return 0;
592
593         return 1;
594 }
595
596 /* What is the scope of 'addr'?  */
597 static sctp_scope_t sctp_v6_scope(union sctp_addr *addr)
598 {
599         int v6scope;
600         sctp_scope_t retval;
601
602         /* The IPv6 scope is really a set of bit fields.
603          * See IFA_* in <net/if_inet6.h>.  Map to a generic SCTP scope.
604          */
605
606         v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
607         switch (v6scope) {
608         case IFA_HOST:
609                 retval = SCTP_SCOPE_LOOPBACK;
610                 break;
611         case IFA_LINK:
612                 retval = SCTP_SCOPE_LINK;
613                 break;
614         case IFA_SITE:
615                 retval = SCTP_SCOPE_PRIVATE;
616                 break;
617         default:
618                 retval = SCTP_SCOPE_GLOBAL;
619                 break;
620         }
621
622         return retval;
623 }
624
625 /* Create and initialize a new sk for the socket to be returned by accept(). */
626 static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
627                                              struct sctp_association *asoc)
628 {
629         struct inet_sock *inet = inet_sk(sk);
630         struct sock *newsk;
631         struct inet_sock *newinet;
632         struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
633         struct sctp6_sock *newsctp6sk;
634
635         newsk = sk_alloc(sk->sk_net, PF_INET6, GFP_KERNEL, sk->sk_prot);
636         if (!newsk)
637                 goto out;
638
639         sock_init_data(NULL, newsk);
640
641         newsk->sk_type = SOCK_STREAM;
642
643         newsk->sk_prot = sk->sk_prot;
644         newsk->sk_no_check = sk->sk_no_check;
645         newsk->sk_reuse = sk->sk_reuse;
646
647         newsk->sk_destruct = inet_sock_destruct;
648         newsk->sk_family = PF_INET6;
649         newsk->sk_protocol = IPPROTO_SCTP;
650         newsk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
651         newsk->sk_shutdown = sk->sk_shutdown;
652         sock_reset_flag(sk, SOCK_ZAPPED);
653
654         newsctp6sk = (struct sctp6_sock *)newsk;
655         inet_sk(newsk)->pinet6 = &newsctp6sk->inet6;
656
657         sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped;
658
659         newinet = inet_sk(newsk);
660         newnp = inet6_sk(newsk);
661
662         memcpy(newnp, np, sizeof(struct ipv6_pinfo));
663
664         /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
665          * and getpeername().
666          */
667         newinet->sport = inet->sport;
668         newnp->saddr = np->saddr;
669         newnp->rcv_saddr = np->rcv_saddr;
670         newinet->dport = htons(asoc->peer.port);
671         sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
672
673         /* Init the ipv4 part of the socket since we can have sockets
674          * using v6 API for ipv4.
675          */
676         newinet->uc_ttl = -1;
677         newinet->mc_loop = 1;
678         newinet->mc_ttl = 1;
679         newinet->mc_index = 0;
680         newinet->mc_list = NULL;
681
682         if (ipv4_config.no_pmtu_disc)
683                 newinet->pmtudisc = IP_PMTUDISC_DONT;
684         else
685                 newinet->pmtudisc = IP_PMTUDISC_WANT;
686
687         sk_refcnt_debug_inc(newsk);
688
689         if (newsk->sk_prot->init(newsk)) {
690                 sk_common_release(newsk);
691                 newsk = NULL;
692         }
693
694 out:
695         return newsk;
696 }
697
698 /* Map v4 address to mapped v6 address */
699 static void sctp_v6_addr_v4map(struct sctp_sock *sp, union sctp_addr *addr)
700 {
701         if (sp->v4mapped && AF_INET == addr->sa.sa_family)
702                 sctp_v4_map_v6(addr);
703 }
704
705 /* Where did this skb come from?  */
706 static int sctp_v6_skb_iif(const struct sk_buff *skb)
707 {
708         struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb;
709         return opt->iif;
710 }
711
712 /* Was this packet marked by Explicit Congestion Notification? */
713 static int sctp_v6_is_ce(const struct sk_buff *skb)
714 {
715         return *((__u32 *)(ipv6_hdr(skb))) & htonl(1 << 20);
716 }
717
718 /* Dump the v6 addr to the seq file. */
719 static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
720 {
721         seq_printf(seq, NIP6_FMT " ", NIP6(addr->v6.sin6_addr));
722 }
723
724 /* Initialize a PF_INET6 socket msg_name. */
725 static void sctp_inet6_msgname(char *msgname, int *addr_len)
726 {
727         struct sockaddr_in6 *sin6;
728
729         sin6 = (struct sockaddr_in6 *)msgname;
730         sin6->sin6_family = AF_INET6;
731         sin6->sin6_flowinfo = 0;
732         sin6->sin6_scope_id = 0; /*FIXME */
733         *addr_len = sizeof(struct sockaddr_in6);
734 }
735
736 /* Initialize a PF_INET msgname from a ulpevent. */
737 static void sctp_inet6_event_msgname(struct sctp_ulpevent *event,
738                                      char *msgname, int *addrlen)
739 {
740         struct sockaddr_in6 *sin6, *sin6from;
741
742         if (msgname) {
743                 union sctp_addr *addr;
744                 struct sctp_association *asoc;
745
746                 asoc = event->asoc;
747                 sctp_inet6_msgname(msgname, addrlen);
748                 sin6 = (struct sockaddr_in6 *)msgname;
749                 sin6->sin6_port = htons(asoc->peer.port);
750                 addr = &asoc->peer.primary_addr;
751
752                 /* Note: If we go to a common v6 format, this code
753                  * will change.
754                  */
755
756                 /* Map ipv4 address into v4-mapped-on-v6 address.  */
757                 if (sctp_sk(asoc->base.sk)->v4mapped &&
758                     AF_INET == addr->sa.sa_family) {
759                         sctp_v4_map_v6((union sctp_addr *)sin6);
760                         sin6->sin6_addr.s6_addr32[3] =
761                                 addr->v4.sin_addr.s_addr;
762                         return;
763                 }
764
765                 sin6from = &asoc->peer.primary_addr.v6;
766                 ipv6_addr_copy(&sin6->sin6_addr, &sin6from->sin6_addr);
767                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
768                         sin6->sin6_scope_id = sin6from->sin6_scope_id;
769         }
770 }
771
772 /* Initialize a msg_name from an inbound skb. */
773 static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname,
774                                    int *addr_len)
775 {
776         struct sctphdr *sh;
777         struct sockaddr_in6 *sin6;
778
779         if (msgname) {
780                 sctp_inet6_msgname(msgname, addr_len);
781                 sin6 = (struct sockaddr_in6 *)msgname;
782                 sh = sctp_hdr(skb);
783                 sin6->sin6_port = sh->source;
784
785                 /* Map ipv4 address into v4-mapped-on-v6 address. */
786                 if (sctp_sk(skb->sk)->v4mapped &&
787                     ip_hdr(skb)->version == 4) {
788                         sctp_v4_map_v6((union sctp_addr *)sin6);
789                         sin6->sin6_addr.s6_addr32[3] = ip_hdr(skb)->saddr;
790                         return;
791                 }
792
793                 /* Otherwise, just copy the v6 address. */
794                 ipv6_addr_copy(&sin6->sin6_addr, &ipv6_hdr(skb)->saddr);
795                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) {
796                         struct sctp_ulpevent *ev = sctp_skb2event(skb);
797                         sin6->sin6_scope_id = ev->iif;
798                 }
799         }
800 }
801
802 /* Do we support this AF? */
803 static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp)
804 {
805         switch (family) {
806         case AF_INET6:
807                 return 1;
808         /* v4-mapped-v6 addresses */
809         case AF_INET:
810                 if (!__ipv6_only_sock(sctp_opt2sk(sp)) && sp->v4mapped)
811                         return 1;
812         default:
813                 return 0;
814         }
815 }
816
817 /* Address matching with wildcards allowed.  This extra level
818  * of indirection lets us choose whether a PF_INET6 should
819  * disallow any v4 addresses if we so choose.
820  */
821 static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
822                                const union sctp_addr *addr2,
823                                struct sctp_sock *opt)
824 {
825         struct sctp_af *af1, *af2;
826
827         af1 = sctp_get_af_specific(addr1->sa.sa_family);
828         af2 = sctp_get_af_specific(addr2->sa.sa_family);
829
830         if (!af1 || !af2)
831                 return 0;
832         /* Today, wildcard AF_INET/AF_INET6. */
833         if (sctp_is_any(addr1) || sctp_is_any(addr2))
834                 return 1;
835
836         if (addr1->sa.sa_family != addr2->sa.sa_family)
837                 return 0;
838
839         return af1->cmp_addr(addr1, addr2);
840 }
841
842 /* Verify that the provided sockaddr looks bindable.   Common verification,
843  * has already been taken care of.
844  */
845 static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
846 {
847         struct sctp_af *af;
848
849         /* ASSERT: address family has already been verified. */
850         if (addr->sa.sa_family != AF_INET6)
851                 af = sctp_get_af_specific(addr->sa.sa_family);
852         else {
853                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
854                 struct net_device *dev;
855
856                 if (type & IPV6_ADDR_LINKLOCAL) {
857                         if (!addr->v6.sin6_scope_id)
858                                 return 0;
859                         dev = dev_get_by_index(&init_net, addr->v6.sin6_scope_id);
860                         if (!dev)
861                                 return 0;
862                         if (!ipv6_chk_addr(&init_net, &addr->v6.sin6_addr,
863                                            dev, 0)) {
864                                 dev_put(dev);
865                                 return 0;
866                         }
867                         dev_put(dev);
868                 }
869                 af = opt->pf->af;
870         }
871         return af->available(addr, opt);
872 }
873
874 /* Verify that the provided sockaddr looks sendable.   Common verification,
875  * has already been taken care of.
876  */
877 static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
878 {
879         struct sctp_af *af = NULL;
880
881         /* ASSERT: address family has already been verified. */
882         if (addr->sa.sa_family != AF_INET6)
883                 af = sctp_get_af_specific(addr->sa.sa_family);
884         else {
885                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
886                 struct net_device *dev;
887
888                 if (type & IPV6_ADDR_LINKLOCAL) {
889                         if (!addr->v6.sin6_scope_id)
890                                 return 0;
891                         dev = dev_get_by_index(&init_net, addr->v6.sin6_scope_id);
892                         if (!dev)
893                                 return 0;
894                         dev_put(dev);
895                 }
896                 af = opt->pf->af;
897         }
898
899         return af != NULL;
900 }
901
902 /* Fill in Supported Address Type information for INIT and INIT-ACK
903  * chunks.   Note: In the future, we may want to look at sock options
904  * to determine whether a PF_INET6 socket really wants to have IPV4
905  * addresses.
906  * Returns number of addresses supported.
907  */
908 static int sctp_inet6_supported_addrs(const struct sctp_sock *opt,
909                                       __be16 *types)
910 {
911         types[0] = SCTP_PARAM_IPV4_ADDRESS;
912         types[1] = SCTP_PARAM_IPV6_ADDRESS;
913         return 2;
914 }
915
916 static const struct proto_ops inet6_seqpacket_ops = {
917         .family            = PF_INET6,
918         .owner             = THIS_MODULE,
919         .release           = inet6_release,
920         .bind              = inet6_bind,
921         .connect           = inet_dgram_connect,
922         .socketpair        = sock_no_socketpair,
923         .accept            = inet_accept,
924         .getname           = inet6_getname,
925         .poll              = sctp_poll,
926         .ioctl             = inet6_ioctl,
927         .listen            = sctp_inet_listen,
928         .shutdown          = inet_shutdown,
929         .setsockopt        = sock_common_setsockopt,
930         .getsockopt        = sock_common_getsockopt,
931         .sendmsg           = inet_sendmsg,
932         .recvmsg           = sock_common_recvmsg,
933         .mmap              = sock_no_mmap,
934 #ifdef CONFIG_COMPAT
935         .compat_setsockopt = compat_sock_common_setsockopt,
936         .compat_getsockopt = compat_sock_common_getsockopt,
937 #endif
938 };
939
940 static struct inet_protosw sctpv6_seqpacket_protosw = {
941         .type          = SOCK_SEQPACKET,
942         .protocol      = IPPROTO_SCTP,
943         .prot          = &sctpv6_prot,
944         .ops           = &inet6_seqpacket_ops,
945         .capability    = -1,
946         .no_check      = 0,
947         .flags         = SCTP_PROTOSW_FLAG
948 };
949 static struct inet_protosw sctpv6_stream_protosw = {
950         .type          = SOCK_STREAM,
951         .protocol      = IPPROTO_SCTP,
952         .prot          = &sctpv6_prot,
953         .ops           = &inet6_seqpacket_ops,
954         .capability    = -1,
955         .no_check      = 0,
956         .flags         = SCTP_PROTOSW_FLAG,
957 };
958
959 static int sctp6_rcv(struct sk_buff *skb)
960 {
961         return sctp_rcv(skb) ? -1 : 0;
962 }
963
964 static struct inet6_protocol sctpv6_protocol = {
965         .handler      = sctp6_rcv,
966         .err_handler  = sctp_v6_err,
967         .flags        = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
968 };
969
970 static struct sctp_af sctp_af_inet6 = {
971         .sa_family         = AF_INET6,
972         .sctp_xmit         = sctp_v6_xmit,
973         .setsockopt        = ipv6_setsockopt,
974         .getsockopt        = ipv6_getsockopt,
975         .get_dst           = sctp_v6_get_dst,
976         .get_saddr         = sctp_v6_get_saddr,
977         .copy_addrlist     = sctp_v6_copy_addrlist,
978         .from_skb          = sctp_v6_from_skb,
979         .from_sk           = sctp_v6_from_sk,
980         .to_sk_saddr       = sctp_v6_to_sk_saddr,
981         .to_sk_daddr       = sctp_v6_to_sk_daddr,
982         .from_addr_param   = sctp_v6_from_addr_param,
983         .to_addr_param     = sctp_v6_to_addr_param,
984         .dst_saddr         = sctp_v6_dst_saddr,
985         .cmp_addr          = sctp_v6_cmp_addr,
986         .scope             = sctp_v6_scope,
987         .addr_valid        = sctp_v6_addr_valid,
988         .inaddr_any        = sctp_v6_inaddr_any,
989         .is_any            = sctp_v6_is_any,
990         .available         = sctp_v6_available,
991         .skb_iif           = sctp_v6_skb_iif,
992         .is_ce             = sctp_v6_is_ce,
993         .seq_dump_addr     = sctp_v6_seq_dump_addr,
994         .net_header_len    = sizeof(struct ipv6hdr),
995         .sockaddr_len      = sizeof(struct sockaddr_in6),
996 #ifdef CONFIG_COMPAT
997         .compat_setsockopt = compat_ipv6_setsockopt,
998         .compat_getsockopt = compat_ipv6_getsockopt,
999 #endif
1000 };
1001
1002 static struct sctp_pf sctp_pf_inet6 = {
1003         .event_msgname = sctp_inet6_event_msgname,
1004         .skb_msgname   = sctp_inet6_skb_msgname,
1005         .af_supported  = sctp_inet6_af_supported,
1006         .cmp_addr      = sctp_inet6_cmp_addr,
1007         .bind_verify   = sctp_inet6_bind_verify,
1008         .send_verify   = sctp_inet6_send_verify,
1009         .supported_addrs = sctp_inet6_supported_addrs,
1010         .create_accept_sk = sctp_v6_create_accept_sk,
1011         .addr_v4map    = sctp_v6_addr_v4map,
1012         .af            = &sctp_af_inet6,
1013 };
1014
1015 /* Initialize IPv6 support and register with socket layer.  */
1016 int sctp_v6_init(void)
1017 {
1018         int rc;
1019
1020         /* Register the SCTP specific PF_INET6 functions. */
1021         sctp_register_pf(&sctp_pf_inet6, PF_INET6);
1022
1023         /* Register the SCTP specific AF_INET6 functions. */
1024         sctp_register_af(&sctp_af_inet6);
1025
1026         rc = proto_register(&sctpv6_prot, 1);
1027         if (rc)
1028                 return rc;
1029
1030         /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
1031         inet6_register_protosw(&sctpv6_seqpacket_protosw);
1032         inet6_register_protosw(&sctpv6_stream_protosw);
1033
1034         return 0;
1035 }
1036
1037 /* Register with inet6 layer. */
1038 int sctp_v6_add_protocol(void)
1039 {
1040         /* Register notifier for inet6 address additions/deletions. */
1041         register_inet6addr_notifier(&sctp_inet6addr_notifier);
1042
1043         if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
1044                 return -EAGAIN;
1045
1046         return 0;
1047 }
1048
1049 /* IPv6 specific exit support. */
1050 void sctp_v6_exit(void)
1051 {
1052         inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
1053         inet6_unregister_protosw(&sctpv6_stream_protosw);
1054         proto_unregister(&sctpv6_prot);
1055         list_del(&sctp_af_inet6.list);
1056 }
1057
1058 /* Unregister with inet6 layer. */
1059 void sctp_v6_del_protocol(void)
1060 {
1061         inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
1062         unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
1063 }