Linux-2.6.12-rc2
[linux-2.6.git] / net / sctp / ipv6.c
1 /* SCTP kernel reference Implementation
2  * (C) Copyright IBM Corp. 2002, 2004
3  * Copyright (c) 2001 Nokia, Inc.
4  * Copyright (c) 2001 La Monte H.P. Yarroll
5  * Copyright (c) 2002-2003 Intel Corp.
6  *
7  * This file is part of the SCTP kernel reference Implementation
8  *
9  * SCTP over IPv6.
10  *
11  * The SCTP reference implementation is free software;
12  * you can redistribute it and/or modify it under the terms of
13  * the GNU General Public License as published by
14  * the Free Software Foundation; either version 2, or (at your option)
15  * any later version.
16  *
17  * The SCTP reference implementation is distributed in the hope that it
18  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
19  *                 ************************
20  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
21  * See the GNU General Public License for more details.
22  *
23  * You should have received a copy of the GNU General Public License
24  * along with GNU CC; see the file COPYING.  If not, write to
25  * the Free Software Foundation, 59 Temple Place - Suite 330,
26  * Boston, MA 02111-1307, USA.
27  *
28  * Please send any bug reports or fixes you make to the
29  * email address(es):
30  *    lksctp developers <lksctp-developers@lists.sourceforge.net>
31  *
32  * Or submit a bug report through the following website:
33  *    http://www.sf.net/projects/lksctp
34  *
35  * Written or modified by:
36  *    Le Yanqun             <yanqun.le@nokia.com>
37  *    Hui Huang             <hui.huang@nokia.com>
38  *    La Monte H.P. Yarroll <piggy@acm.org>
39  *    Sridhar Samudrala     <sri@us.ibm.com>
40  *    Jon Grimm             <jgrimm@us.ibm.com>
41  *    Ardelle Fan           <ardelle.fan@intel.com>
42  *
43  * Based on:
44  *      linux/net/ipv6/tcp_ipv6.c
45  *
46  * Any bugs reported given to us we will try to fix... any fixes shared will
47  * be incorporated into the next SCTP release.
48  */
49
50 #include <linux/module.h>
51 #include <linux/errno.h>
52 #include <linux/types.h>
53 #include <linux/socket.h>
54 #include <linux/sockios.h>
55 #include <linux/net.h>
56 #include <linux/sched.h>
57 #include <linux/in.h>
58 #include <linux/in6.h>
59 #include <linux/netdevice.h>
60 #include <linux/init.h>
61 #include <linux/ipsec.h>
62
63 #include <linux/ipv6.h>
64 #include <linux/icmpv6.h>
65 #include <linux/random.h>
66 #include <linux/seq_file.h>
67
68 #include <net/protocol.h>
69 #include <net/tcp.h>
70 #include <net/ndisc.h>
71 #include <net/ipv6.h>
72 #include <net/transp_v6.h>
73 #include <net/addrconf.h>
74 #include <net/ip6_route.h>
75 #include <net/inet_common.h>
76 #include <net/inet_ecn.h>
77 #include <net/sctp/sctp.h>
78
79 #include <asm/uaccess.h>
80
81 extern int sctp_inetaddr_event(struct notifier_block *, unsigned long, void *);
82 static struct notifier_block sctp_inet6addr_notifier = {
83         .notifier_call = sctp_inetaddr_event,
84 };
85
86 /* ICMP error handler. */
87 SCTP_STATIC void sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
88                              int type, int code, int offset, __u32 info)
89 {
90         struct inet6_dev *idev;
91         struct ipv6hdr *iph = (struct ipv6hdr *)skb->data;
92         struct sctphdr *sh = (struct sctphdr *)(skb->data + offset);
93         struct sock *sk;
94         struct sctp_endpoint *ep;
95         struct sctp_association *asoc;
96         struct sctp_transport *transport;
97         struct ipv6_pinfo *np;
98         char *saveip, *savesctp;
99         int err;
100
101         idev = in6_dev_get(skb->dev);
102
103         /* Fix up skb to look at the embedded net header. */
104         saveip = skb->nh.raw;
105         savesctp  = skb->h.raw;
106         skb->nh.ipv6h = iph;
107         skb->h.raw = (char *)sh;
108         sk = sctp_err_lookup(AF_INET6, skb, sh, &ep, &asoc, &transport);
109         /* Put back, the original pointers. */
110         skb->nh.raw = saveip;
111         skb->h.raw = savesctp;
112         if (!sk) {
113                 ICMP6_INC_STATS_BH(idev, ICMP6_MIB_INERRORS);
114                 goto out;
115         }
116
117         /* Warning:  The sock lock is held.  Remember to call
118          * sctp_err_finish!
119          */
120
121         switch (type) {
122         case ICMPV6_PKT_TOOBIG:
123                 sctp_icmp_frag_needed(sk, asoc, transport, ntohl(info));
124                 goto out_unlock;
125         case ICMPV6_PARAMPROB:
126                 if (ICMPV6_UNK_NEXTHDR == code) {
127                         sctp_icmp_proto_unreachable(sk, ep, asoc, transport);
128                         goto out_unlock;
129                 }
130                 break;
131         default:
132                 break;
133         }
134
135         np = inet6_sk(sk);
136         icmpv6_err_convert(type, code, &err);
137         if (!sock_owned_by_user(sk) && np->recverr) {
138                 sk->sk_err = err;
139                 sk->sk_error_report(sk);
140         } else {  /* Only an error on timeout */
141                 sk->sk_err_soft = err;
142         }
143
144 out_unlock:
145         sctp_err_finish(sk, ep, asoc);
146 out:
147         if (likely(idev != NULL))
148                 in6_dev_put(idev);
149 }
150
151 /* Based on tcp_v6_xmit() in tcp_ipv6.c. */
152 static int sctp_v6_xmit(struct sk_buff *skb, struct sctp_transport *transport,
153                         int ipfragok)
154 {
155         struct sock *sk = skb->sk;
156         struct ipv6_pinfo *np = inet6_sk(sk);
157         struct flowi fl;
158
159         memset(&fl, 0, sizeof(fl));
160
161         fl.proto = sk->sk_protocol;
162
163         /* Fill in the dest address from the route entry passed with the skb
164          * and the source address from the transport.
165          */
166         ipv6_addr_copy(&fl.fl6_dst, &transport->ipaddr.v6.sin6_addr);
167         ipv6_addr_copy(&fl.fl6_src, &transport->saddr.v6.sin6_addr);
168
169         fl.fl6_flowlabel = np->flow_label;
170         IP6_ECN_flow_xmit(sk, fl.fl6_flowlabel);
171         if (ipv6_addr_type(&fl.fl6_src) & IPV6_ADDR_LINKLOCAL)
172                 fl.oif = transport->saddr.v6.sin6_scope_id;
173         else
174                 fl.oif = sk->sk_bound_dev_if;
175         fl.fl_ip_sport = inet_sk(sk)->sport;
176         fl.fl_ip_dport = transport->ipaddr.v6.sin6_port;
177
178         if (np->opt && np->opt->srcrt) {
179                 struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt;
180                 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
181         }
182
183         SCTP_DEBUG_PRINTK("%s: skb:%p, len:%d, "
184                           "src:%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x "
185                           "dst:%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
186                           __FUNCTION__, skb, skb->len,
187                           NIP6(fl.fl6_src), NIP6(fl.fl6_dst));
188
189         SCTP_INC_STATS(SCTP_MIB_OUTSCTPPACKS);
190
191         return ip6_xmit(sk, skb, &fl, np->opt, ipfragok);
192 }
193
194 /* Returns the dst cache entry for the given source and destination ip
195  * addresses.
196  */
197 static struct dst_entry *sctp_v6_get_dst(struct sctp_association *asoc,
198                                          union sctp_addr *daddr,
199                                          union sctp_addr *saddr)
200 {
201         struct dst_entry *dst;
202         struct flowi fl;
203
204         memset(&fl, 0, sizeof(fl));
205         ipv6_addr_copy(&fl.fl6_dst, &daddr->v6.sin6_addr);
206         if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
207                 fl.oif = daddr->v6.sin6_scope_id;
208         
209
210         SCTP_DEBUG_PRINTK("%s: DST=%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x ",
211                           __FUNCTION__, NIP6(fl.fl6_dst));
212
213         if (saddr) {
214                 ipv6_addr_copy(&fl.fl6_src, &saddr->v6.sin6_addr);
215                 SCTP_DEBUG_PRINTK(
216                         "SRC=%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x - ",
217                         NIP6(fl.fl6_src));
218         }
219
220         dst = ip6_route_output(NULL, &fl);
221         if (dst) {
222                 struct rt6_info *rt;
223                 rt = (struct rt6_info *)dst;
224                 SCTP_DEBUG_PRINTK(
225                         "rt6_dst:%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x "
226                         "rt6_src:%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
227                         NIP6(rt->rt6i_dst.addr), NIP6(rt->rt6i_src.addr));
228         } else {
229                 SCTP_DEBUG_PRINTK("NO ROUTE\n");
230         }
231
232         return dst;
233 }
234
235 /* Returns the number of consecutive initial bits that match in the 2 ipv6
236  * addresses.
237  */
238 static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
239                                          union sctp_addr *s2)
240 {
241         struct in6_addr *a1 = &s1->v6.sin6_addr;
242         struct in6_addr *a2 = &s2->v6.sin6_addr;
243         int i, j;
244
245         for (i = 0; i < 4 ; i++) {
246                 __u32 a1xora2;
247
248                 a1xora2 = a1->s6_addr32[i] ^ a2->s6_addr32[i];
249
250                 if ((j = fls(ntohl(a1xora2))))
251                         return (i * 32 + 32 - j);
252         }
253
254         return (i*32);
255 }
256
257 /* Fills in the source address(saddr) based on the destination address(daddr)
258  * and asoc's bind address list.
259  */
260 static void sctp_v6_get_saddr(struct sctp_association *asoc,
261                               struct dst_entry *dst,
262                               union sctp_addr *daddr,
263                               union sctp_addr *saddr)
264 {
265         struct sctp_bind_addr *bp;
266         rwlock_t *addr_lock;
267         struct sctp_sockaddr_entry *laddr;
268         struct list_head *pos;
269         sctp_scope_t scope;
270         union sctp_addr *baddr = NULL;
271         __u8 matchlen = 0;
272         __u8 bmatchlen;
273
274         SCTP_DEBUG_PRINTK("%s: asoc:%p dst:%p "
275                           "daddr:%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x ",
276                           __FUNCTION__, asoc, dst, NIP6(daddr->v6.sin6_addr));
277
278         if (!asoc) {
279                 ipv6_get_saddr(dst, &daddr->v6.sin6_addr,&saddr->v6.sin6_addr);
280                 SCTP_DEBUG_PRINTK("saddr from ipv6_get_saddr: "
281                                   "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
282                                   NIP6(saddr->v6.sin6_addr));
283                 return;
284         }
285
286         scope = sctp_scope(daddr);
287
288         bp = &asoc->base.bind_addr;
289         addr_lock = &asoc->base.addr_lock;
290
291         /* Go through the bind address list and find the best source address
292          * that matches the scope of the destination address.
293          */
294         sctp_read_lock(addr_lock);
295         list_for_each(pos, &bp->address_list) {
296                 laddr = list_entry(pos, struct sctp_sockaddr_entry, list);
297                 if ((laddr->a.sa.sa_family == AF_INET6) &&
298                     (scope <= sctp_scope(&laddr->a))) {
299                         bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a);
300                         if (!baddr || (matchlen < bmatchlen)) {
301                                 baddr = &laddr->a;
302                                 matchlen = bmatchlen;
303                         }
304                 }
305         }
306
307         if (baddr) {
308                 memcpy(saddr, baddr, sizeof(union sctp_addr));
309                 SCTP_DEBUG_PRINTK("saddr: "
310                                   "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
311                                   NIP6(saddr->v6.sin6_addr));
312         } else {
313                 printk(KERN_ERR "%s: asoc:%p Could not find a valid source "
314                        "address for the "
315                        "dest:%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
316                        __FUNCTION__, asoc, NIP6(daddr->v6.sin6_addr));
317         }
318
319         sctp_read_unlock(addr_lock);
320 }
321
322 /* Make a copy of all potential local addresses. */
323 static void sctp_v6_copy_addrlist(struct list_head *addrlist,
324                                   struct net_device *dev)
325 {
326         struct inet6_dev *in6_dev;
327         struct inet6_ifaddr *ifp;
328         struct sctp_sockaddr_entry *addr;
329
330         read_lock(&addrconf_lock);
331         if ((in6_dev = __in6_dev_get(dev)) == NULL) {
332                 read_unlock(&addrconf_lock);
333                 return;
334         }
335
336         read_lock(&in6_dev->lock);
337         for (ifp = in6_dev->addr_list; ifp; ifp = ifp->if_next) {
338                 /* Add the address to the local list.  */
339                 addr = t_new(struct sctp_sockaddr_entry, GFP_ATOMIC);
340                 if (addr) {
341                         addr->a.v6.sin6_family = AF_INET6;
342                         addr->a.v6.sin6_port = 0;
343                         addr->a.v6.sin6_addr = ifp->addr;
344                         addr->a.v6.sin6_scope_id = dev->ifindex;
345                         INIT_LIST_HEAD(&addr->list);
346                         list_add_tail(&addr->list, addrlist);
347                 }
348         }
349
350         read_unlock(&in6_dev->lock);
351         read_unlock(&addrconf_lock);
352 }
353
354 /* Initialize a sockaddr_storage from in incoming skb. */
355 static void sctp_v6_from_skb(union sctp_addr *addr,struct sk_buff *skb,
356                              int is_saddr)
357 {
358         void *from;
359         __u16 *port;
360         struct sctphdr *sh;
361
362         port = &addr->v6.sin6_port;
363         addr->v6.sin6_family = AF_INET6;
364         addr->v6.sin6_flowinfo = 0; /* FIXME */
365         addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif;
366
367         sh = (struct sctphdr *) skb->h.raw;
368         if (is_saddr) {
369                 *port  = ntohs(sh->source);
370                 from = &skb->nh.ipv6h->saddr;
371         } else {
372                 *port = ntohs(sh->dest);
373                 from = &skb->nh.ipv6h->daddr;
374         }
375         ipv6_addr_copy(&addr->v6.sin6_addr, from);
376 }
377
378 /* Initialize an sctp_addr from a socket. */
379 static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk)
380 {
381         addr->v6.sin6_family = AF_INET6;
382         addr->v6.sin6_port = inet_sk(sk)->num;
383         addr->v6.sin6_addr = inet6_sk(sk)->rcv_saddr;
384 }
385
386 /* Initialize sk->sk_rcv_saddr from sctp_addr. */
387 static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
388 {
389         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
390                 inet6_sk(sk)->rcv_saddr.s6_addr32[0] = 0;
391                 inet6_sk(sk)->rcv_saddr.s6_addr32[1] = 0;
392                 inet6_sk(sk)->rcv_saddr.s6_addr32[2] = htonl(0x0000ffff);
393                 inet6_sk(sk)->rcv_saddr.s6_addr32[3] =
394                         addr->v4.sin_addr.s_addr;
395         } else {
396                 inet6_sk(sk)->rcv_saddr = addr->v6.sin6_addr;
397         }
398 }
399
400 /* Initialize sk->sk_daddr from sctp_addr. */
401 static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
402 {
403         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
404                 inet6_sk(sk)->daddr.s6_addr32[0] = 0;
405                 inet6_sk(sk)->daddr.s6_addr32[1] = 0;
406                 inet6_sk(sk)->daddr.s6_addr32[2] = htonl(0x0000ffff);
407                 inet6_sk(sk)->daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
408         } else {
409                 inet6_sk(sk)->daddr = addr->v6.sin6_addr;
410         }
411 }
412
413 /* Initialize a sctp_addr from an address parameter. */
414 static void sctp_v6_from_addr_param(union sctp_addr *addr,
415                                     union sctp_addr_param *param,
416                                     __u16 port, int iif)
417 {
418         addr->v6.sin6_family = AF_INET6;
419         addr->v6.sin6_port = port;
420         addr->v6.sin6_flowinfo = 0; /* BUG */
421         ipv6_addr_copy(&addr->v6.sin6_addr, &param->v6.addr);
422         addr->v6.sin6_scope_id = iif;
423 }
424
425 /* Initialize an address parameter from a sctp_addr and return the length
426  * of the address parameter.
427  */
428 static int sctp_v6_to_addr_param(const union sctp_addr *addr,
429                                  union sctp_addr_param *param)
430 {
431         int length = sizeof(sctp_ipv6addr_param_t);
432
433         param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS;
434         param->v6.param_hdr.length = ntohs(length);
435         ipv6_addr_copy(&param->v6.addr, &addr->v6.sin6_addr);
436
437         return length;
438 }
439
440 /* Initialize a sctp_addr from a dst_entry. */
441 static void sctp_v6_dst_saddr(union sctp_addr *addr, struct dst_entry *dst,
442                               unsigned short port)
443 {
444         struct rt6_info *rt = (struct rt6_info *)dst;
445         addr->sa.sa_family = AF_INET6;
446         addr->v6.sin6_port = port;
447         ipv6_addr_copy(&addr->v6.sin6_addr, &rt->rt6i_src.addr);
448 }
449
450 /* Compare addresses exactly.
451  * v4-mapped-v6 is also in consideration.
452  */
453 static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
454                             const union sctp_addr *addr2)
455 {
456         if (addr1->sa.sa_family != addr2->sa.sa_family) {
457                 if (addr1->sa.sa_family == AF_INET &&
458                     addr2->sa.sa_family == AF_INET6 &&
459                     IPV6_ADDR_MAPPED == ipv6_addr_type(&addr2->v6.sin6_addr)) {
460                         if (addr2->v6.sin6_port == addr1->v4.sin_port &&
461                             addr2->v6.sin6_addr.s6_addr32[3] ==
462                             addr1->v4.sin_addr.s_addr)
463                                 return 1;
464                 }
465                 if (addr2->sa.sa_family == AF_INET &&
466                     addr1->sa.sa_family == AF_INET6 &&
467                     IPV6_ADDR_MAPPED == ipv6_addr_type(&addr1->v6.sin6_addr)) {
468                         if (addr1->v6.sin6_port == addr2->v4.sin_port &&
469                             addr1->v6.sin6_addr.s6_addr32[3] ==
470                             addr2->v4.sin_addr.s_addr)
471                                 return 1;
472                 }
473                 return 0;
474         }
475         if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))
476                 return 0;
477         /* If this is a linklocal address, compare the scope_id. */
478         if (ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) {
479                 if (addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&
480                     (addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)) {
481                         return 0;
482                 }
483         }
484
485         return 1;
486 }
487
488 /* Initialize addr struct to INADDR_ANY. */
489 static void sctp_v6_inaddr_any(union sctp_addr *addr, unsigned short port)
490 {
491         memset(addr, 0x00, sizeof(union sctp_addr));
492         addr->v6.sin6_family = AF_INET6;
493         addr->v6.sin6_port = port;
494 }
495
496 /* Is this a wildcard address? */
497 static int sctp_v6_is_any(const union sctp_addr *addr)
498 {
499         int type;
500         type = ipv6_addr_type((struct in6_addr *)&addr->v6.sin6_addr);
501         return IPV6_ADDR_ANY == type;
502 }
503
504 /* Should this be available for binding?   */
505 static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp)
506 {
507         int type;
508         struct in6_addr *in6 = (struct in6_addr *)&addr->v6.sin6_addr;
509
510         type = ipv6_addr_type(in6);
511         if (IPV6_ADDR_ANY == type)
512                 return 1;
513         if (type == IPV6_ADDR_MAPPED) {
514                 if (sp && !sp->v4mapped)
515                         return 0;
516                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
517                         return 0;
518                 sctp_v6_map_v4(addr);
519                 return sctp_get_af_specific(AF_INET)->available(addr, sp);
520         }
521         if (!(type & IPV6_ADDR_UNICAST))
522                 return 0;
523
524         return ipv6_chk_addr(in6, NULL, 0);
525 }
526
527 /* This function checks if the address is a valid address to be used for
528  * SCTP.
529  *
530  * Output:
531  * Return 0 - If the address is a non-unicast or an illegal address.
532  * Return 1 - If the address is a unicast.
533  */
534 static int sctp_v6_addr_valid(union sctp_addr *addr, struct sctp_sock *sp)
535 {
536         int ret = ipv6_addr_type(&addr->v6.sin6_addr);
537
538         /* Support v4-mapped-v6 address. */
539         if (ret == IPV6_ADDR_MAPPED) {
540                 /* Note: This routine is used in input, so v4-mapped-v6
541                  * are disallowed here when there is no sctp_sock.
542                  */
543                 if (!sp || !sp->v4mapped)
544                         return 0;
545                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
546                         return 0;
547                 sctp_v6_map_v4(addr);
548                 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp);
549         }
550
551         /* Is this a non-unicast address */
552         if (!(ret & IPV6_ADDR_UNICAST))
553                 return 0;
554
555         return 1;
556 }
557
558 /* What is the scope of 'addr'?  */
559 static sctp_scope_t sctp_v6_scope(union sctp_addr *addr)
560 {
561         int v6scope;
562         sctp_scope_t retval;
563
564         /* The IPv6 scope is really a set of bit fields.
565          * See IFA_* in <net/if_inet6.h>.  Map to a generic SCTP scope.
566          */
567
568         v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
569         switch (v6scope) {
570         case IFA_HOST:
571                 retval = SCTP_SCOPE_LOOPBACK;
572                 break;
573         case IFA_LINK:
574                 retval = SCTP_SCOPE_LINK;
575                 break;
576         case IFA_SITE:
577                 retval = SCTP_SCOPE_PRIVATE;
578                 break;
579         default:
580                 retval = SCTP_SCOPE_GLOBAL;
581                 break;
582         };
583
584         return retval;
585 }
586
587 /* Create and initialize a new sk for the socket to be returned by accept(). */
588 static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
589                                              struct sctp_association *asoc)
590 {
591         struct inet_sock *inet = inet_sk(sk);
592         struct sock *newsk;
593         struct inet_sock *newinet;
594         struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
595         struct sctp6_sock *newsctp6sk;
596
597         newsk = sk_alloc(PF_INET6, GFP_KERNEL, sk->sk_prot, 1);
598         if (!newsk)
599                 goto out;
600
601         sock_init_data(NULL, newsk);
602
603         newsk->sk_type = SOCK_STREAM;
604
605         newsk->sk_prot = sk->sk_prot;
606         newsk->sk_no_check = sk->sk_no_check;
607         newsk->sk_reuse = sk->sk_reuse;
608
609         newsk->sk_destruct = inet_sock_destruct;
610         newsk->sk_family = PF_INET6;
611         newsk->sk_protocol = IPPROTO_SCTP;
612         newsk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
613         newsk->sk_shutdown = sk->sk_shutdown;
614         sock_reset_flag(sk, SOCK_ZAPPED);
615
616         newsctp6sk = (struct sctp6_sock *)newsk;
617         inet_sk(newsk)->pinet6 = &newsctp6sk->inet6;
618
619         newinet = inet_sk(newsk);
620         newnp = inet6_sk(newsk);
621
622         memcpy(newnp, np, sizeof(struct ipv6_pinfo));
623
624         /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
625          * and getpeername().
626          */
627         newinet->sport = inet->sport;
628         newnp->saddr = np->saddr;
629         newnp->rcv_saddr = np->rcv_saddr;
630         newinet->dport = htons(asoc->peer.port);
631         sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
632
633         /* Init the ipv4 part of the socket since we can have sockets
634          * using v6 API for ipv4.
635          */
636         newinet->uc_ttl = -1;
637         newinet->mc_loop = 1;
638         newinet->mc_ttl = 1;
639         newinet->mc_index = 0;
640         newinet->mc_list = NULL;
641
642         if (ipv4_config.no_pmtu_disc)
643                 newinet->pmtudisc = IP_PMTUDISC_DONT;
644         else
645                 newinet->pmtudisc = IP_PMTUDISC_WANT;
646
647 #ifdef INET_REFCNT_DEBUG
648         atomic_inc(&inet6_sock_nr);
649         atomic_inc(&inet_sock_nr);
650 #endif
651
652         if (newsk->sk_prot->init(newsk)) {
653                 sk_common_release(newsk);
654                 newsk = NULL;
655         }
656
657 out:
658         return newsk;
659 }
660
661 /* Map v4 address to mapped v6 address */
662 static void sctp_v6_addr_v4map(struct sctp_sock *sp, union sctp_addr *addr)
663 {
664         if (sp->v4mapped && AF_INET == addr->sa.sa_family)
665                 sctp_v4_map_v6(addr);
666 }
667
668 /* Where did this skb come from?  */
669 static int sctp_v6_skb_iif(const struct sk_buff *skb)
670 {
671         struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb;
672         return opt->iif;
673 }
674
675 /* Was this packet marked by Explicit Congestion Notification? */
676 static int sctp_v6_is_ce(const struct sk_buff *skb)
677 {
678         return *((__u32 *)(skb->nh.ipv6h)) & htonl(1<<20);
679 }
680
681 /* Dump the v6 addr to the seq file. */
682 static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
683 {
684         seq_printf(seq, "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x ",
685                    NIP6(addr->v6.sin6_addr));
686 }
687
688 /* Initialize a PF_INET6 socket msg_name. */
689 static void sctp_inet6_msgname(char *msgname, int *addr_len)
690 {
691         struct sockaddr_in6 *sin6;
692
693         sin6 = (struct sockaddr_in6 *)msgname;
694         sin6->sin6_family = AF_INET6;
695         sin6->sin6_flowinfo = 0;
696         sin6->sin6_scope_id = 0; /*FIXME */
697         *addr_len = sizeof(struct sockaddr_in6);
698 }
699
700 /* Initialize a PF_INET msgname from a ulpevent. */
701 static void sctp_inet6_event_msgname(struct sctp_ulpevent *event,
702                                      char *msgname, int *addrlen)
703 {
704         struct sockaddr_in6 *sin6, *sin6from;
705
706         if (msgname) {
707                 union sctp_addr *addr;
708                 struct sctp_association *asoc;
709
710                 asoc = event->asoc;
711                 sctp_inet6_msgname(msgname, addrlen);
712                 sin6 = (struct sockaddr_in6 *)msgname;
713                 sin6->sin6_port = htons(asoc->peer.port);
714                 addr = &asoc->peer.primary_addr;
715
716                 /* Note: If we go to a common v6 format, this code
717                  * will change.
718                  */
719
720                 /* Map ipv4 address into v4-mapped-on-v6 address.  */
721                 if (sctp_sk(asoc->base.sk)->v4mapped &&
722                     AF_INET == addr->sa.sa_family) {
723                         sctp_v4_map_v6((union sctp_addr *)sin6);
724                         sin6->sin6_addr.s6_addr32[3] =
725                                 addr->v4.sin_addr.s_addr;
726                         return;
727                 }
728
729                 sin6from = &asoc->peer.primary_addr.v6;
730                 ipv6_addr_copy(&sin6->sin6_addr, &sin6from->sin6_addr);
731                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
732                         sin6->sin6_scope_id = sin6from->sin6_scope_id;
733         }
734 }
735
736 /* Initialize a msg_name from an inbound skb. */
737 static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname,
738                                    int *addr_len)
739 {
740         struct sctphdr *sh;
741         struct sockaddr_in6 *sin6;
742
743         if (msgname) {
744                 sctp_inet6_msgname(msgname, addr_len);
745                 sin6 = (struct sockaddr_in6 *)msgname;
746                 sh = (struct sctphdr *)skb->h.raw;
747                 sin6->sin6_port = sh->source;
748
749                 /* Map ipv4 address into v4-mapped-on-v6 address. */
750                 if (sctp_sk(skb->sk)->v4mapped &&
751                     skb->nh.iph->version == 4) {
752                         sctp_v4_map_v6((union sctp_addr *)sin6);
753                         sin6->sin6_addr.s6_addr32[3] = skb->nh.iph->saddr;
754                         return;
755                 }
756
757                 /* Otherwise, just copy the v6 address. */
758                 ipv6_addr_copy(&sin6->sin6_addr, &skb->nh.ipv6h->saddr);
759                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) {
760                         struct sctp_ulpevent *ev = sctp_skb2event(skb);
761                         sin6->sin6_scope_id = ev->iif;
762                 }
763         }
764 }
765
766 /* Do we support this AF? */
767 static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp)
768 {
769         switch (family) {
770         case AF_INET6:
771                 return 1;
772         /* v4-mapped-v6 addresses */
773         case AF_INET:
774                 if (!__ipv6_only_sock(sctp_opt2sk(sp)) && sp->v4mapped)
775                         return 1;
776         default:
777                 return 0;
778         }
779 }
780
781 /* Address matching with wildcards allowed.  This extra level
782  * of indirection lets us choose whether a PF_INET6 should
783  * disallow any v4 addresses if we so choose.
784  */
785 static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
786                                const union sctp_addr *addr2,
787                                struct sctp_sock *opt)
788 {
789         struct sctp_af *af1, *af2;
790
791         af1 = sctp_get_af_specific(addr1->sa.sa_family);
792         af2 = sctp_get_af_specific(addr2->sa.sa_family);
793
794         if (!af1 || !af2)
795                 return 0;
796         /* Today, wildcard AF_INET/AF_INET6. */
797         if (sctp_is_any(addr1) || sctp_is_any(addr2))
798                 return 1;
799
800         if (addr1->sa.sa_family != addr2->sa.sa_family)
801                 return 0;
802
803         return af1->cmp_addr(addr1, addr2);
804 }
805
806 /* Verify that the provided sockaddr looks bindable.   Common verification,
807  * has already been taken care of.
808  */
809 static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
810 {
811         struct sctp_af *af;
812
813         /* ASSERT: address family has already been verified. */
814         if (addr->sa.sa_family != AF_INET6)
815                 af = sctp_get_af_specific(addr->sa.sa_family);
816         else {
817                 struct sock *sk;
818                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
819                 sk = sctp_opt2sk(opt);
820                 if (type & IPV6_ADDR_LINKLOCAL) {
821                         /* Note: Behavior similar to af_inet6.c:
822                          *  1) Overrides previous bound_dev_if
823                          *  2) Destructive even if bind isn't successful.
824                          */
825
826                         if (addr->v6.sin6_scope_id)
827                                 sk->sk_bound_dev_if = addr->v6.sin6_scope_id;
828                         if (!sk->sk_bound_dev_if)
829                                 return 0;
830                 }
831                 af = opt->pf->af;
832         }
833         return af->available(addr, opt);
834 }
835
836 /* Verify that the provided sockaddr looks bindable.   Common verification,
837  * has already been taken care of.
838  */
839 static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
840 {
841         struct sctp_af *af = NULL;
842
843         /* ASSERT: address family has already been verified. */
844         if (addr->sa.sa_family != AF_INET6)
845                 af = sctp_get_af_specific(addr->sa.sa_family);
846         else {
847                 struct sock *sk;
848                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
849                 sk = sctp_opt2sk(opt);
850                 if (type & IPV6_ADDR_LINKLOCAL) {
851                         /* Note: Behavior similar to af_inet6.c:
852                          *  1) Overrides previous bound_dev_if
853                          *  2) Destructive even if bind isn't successful.
854                          */
855
856                         if (addr->v6.sin6_scope_id)
857                                 sk->sk_bound_dev_if = addr->v6.sin6_scope_id;
858                         if (!sk->sk_bound_dev_if)
859                                 return 0;
860                 }
861                 af = opt->pf->af;
862         }
863
864         return af != NULL;
865 }
866
867 /* Fill in Supported Address Type information for INIT and INIT-ACK
868  * chunks.   Note: In the future, we may want to look at sock options
869  * to determine whether a PF_INET6 socket really wants to have IPV4
870  * addresses.
871  * Returns number of addresses supported.
872  */
873 static int sctp_inet6_supported_addrs(const struct sctp_sock *opt,
874                                       __u16 *types)
875 {
876         types[0] = SCTP_PARAM_IPV4_ADDRESS;
877         types[1] = SCTP_PARAM_IPV6_ADDRESS;
878         return 2;
879 }
880
881 static struct proto_ops inet6_seqpacket_ops = {
882         .family     = PF_INET6,
883         .owner      = THIS_MODULE,
884         .release    = inet6_release,
885         .bind       = inet6_bind,
886         .connect    = inet_dgram_connect,
887         .socketpair = sock_no_socketpair,
888         .accept     = inet_accept,
889         .getname    = inet6_getname,
890         .poll       = sctp_poll,
891         .ioctl      = inet6_ioctl,
892         .listen     = sctp_inet_listen,
893         .shutdown   = inet_shutdown,
894         .setsockopt = sock_common_setsockopt,
895         .getsockopt = sock_common_getsockopt,
896         .sendmsg    = inet_sendmsg,
897         .recvmsg    = sock_common_recvmsg,
898         .mmap       = sock_no_mmap,
899 };
900
901 static struct inet_protosw sctpv6_seqpacket_protosw = {
902         .type          = SOCK_SEQPACKET,
903         .protocol      = IPPROTO_SCTP,
904         .prot          = &sctpv6_prot,
905         .ops           = &inet6_seqpacket_ops,
906         .capability    = -1,
907         .no_check      = 0,
908         .flags         = SCTP_PROTOSW_FLAG
909 };
910 static struct inet_protosw sctpv6_stream_protosw = {
911         .type          = SOCK_STREAM,
912         .protocol      = IPPROTO_SCTP,
913         .prot          = &sctpv6_prot,
914         .ops           = &inet6_seqpacket_ops,
915         .capability    = -1,
916         .no_check      = 0,
917         .flags         = SCTP_PROTOSW_FLAG,
918 };
919
920 static int sctp6_rcv(struct sk_buff **pskb, unsigned int *nhoffp)
921 {
922         return sctp_rcv(*pskb) ? -1 : 0;
923 }
924
925 static struct inet6_protocol sctpv6_protocol = {
926         .handler      = sctp6_rcv,
927         .err_handler  = sctp_v6_err,
928         .flags        = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
929 };
930
931 static struct sctp_af sctp_ipv6_specific = {
932         .sctp_xmit       = sctp_v6_xmit,
933         .setsockopt      = ipv6_setsockopt,
934         .getsockopt      = ipv6_getsockopt,
935         .get_dst         = sctp_v6_get_dst,
936         .get_saddr       = sctp_v6_get_saddr,
937         .copy_addrlist   = sctp_v6_copy_addrlist,
938         .from_skb        = sctp_v6_from_skb,
939         .from_sk         = sctp_v6_from_sk,
940         .to_sk_saddr     = sctp_v6_to_sk_saddr,
941         .to_sk_daddr     = sctp_v6_to_sk_daddr,
942         .from_addr_param = sctp_v6_from_addr_param,
943         .to_addr_param   = sctp_v6_to_addr_param,
944         .dst_saddr       = sctp_v6_dst_saddr,
945         .cmp_addr        = sctp_v6_cmp_addr,
946         .scope           = sctp_v6_scope,
947         .addr_valid      = sctp_v6_addr_valid,
948         .inaddr_any      = sctp_v6_inaddr_any,
949         .is_any          = sctp_v6_is_any,
950         .available       = sctp_v6_available,
951         .skb_iif         = sctp_v6_skb_iif,
952         .is_ce           = sctp_v6_is_ce,
953         .seq_dump_addr   = sctp_v6_seq_dump_addr,
954         .net_header_len  = sizeof(struct ipv6hdr),
955         .sockaddr_len    = sizeof(struct sockaddr_in6),
956         .sa_family       = AF_INET6,
957 };
958
959 static struct sctp_pf sctp_pf_inet6_specific = {
960         .event_msgname = sctp_inet6_event_msgname,
961         .skb_msgname   = sctp_inet6_skb_msgname,
962         .af_supported  = sctp_inet6_af_supported,
963         .cmp_addr      = sctp_inet6_cmp_addr,
964         .bind_verify   = sctp_inet6_bind_verify,
965         .send_verify   = sctp_inet6_send_verify,
966         .supported_addrs = sctp_inet6_supported_addrs,
967         .create_accept_sk = sctp_v6_create_accept_sk,
968         .addr_v4map    = sctp_v6_addr_v4map,
969         .af            = &sctp_ipv6_specific,
970 };
971
972 /* Initialize IPv6 support and register with inet6 stack.  */
973 int sctp_v6_init(void)
974 {
975         int rc = proto_register(&sctpv6_prot, 1);
976
977         if (rc)
978                 goto out;
979         /* Register inet6 protocol. */
980         rc = -EAGAIN;
981         if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
982                 goto out_unregister_sctp_proto;
983
984         /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
985         inet6_register_protosw(&sctpv6_seqpacket_protosw);
986         inet6_register_protosw(&sctpv6_stream_protosw);
987
988         /* Register the SCTP specific PF_INET6 functions. */
989         sctp_register_pf(&sctp_pf_inet6_specific, PF_INET6);
990
991         /* Register the SCTP specific AF_INET6 functions. */
992         sctp_register_af(&sctp_ipv6_specific);
993
994         /* Register notifier for inet6 address additions/deletions. */
995         register_inet6addr_notifier(&sctp_inet6addr_notifier);
996         rc = 0;
997 out:
998         return rc;
999 out_unregister_sctp_proto:
1000         proto_unregister(&sctpv6_prot);
1001         goto out;
1002 }
1003
1004 /* IPv6 specific exit support. */
1005 void sctp_v6_exit(void)
1006 {
1007         list_del(&sctp_ipv6_specific.list);
1008         inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
1009         inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
1010         inet6_unregister_protosw(&sctpv6_stream_protosw);
1011         unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
1012         proto_unregister(&sctpv6_prot);
1013 }