sctp: Use ipv6_addr_diff() in sctp_v6_addr_match_len().
[~shefty/rdma-dev.git] / net / sctp / ipv6.c
1 /* SCTP kernel implementation
2  * (C) Copyright IBM Corp. 2002, 2004
3  * Copyright (c) 2001 Nokia, Inc.
4  * Copyright (c) 2001 La Monte H.P. Yarroll
5  * Copyright (c) 2002-2003 Intel Corp.
6  *
7  * This file is part of the SCTP kernel implementation
8  *
9  * SCTP over IPv6.
10  *
11  * This SCTP implementation is free software;
12  * you can redistribute it and/or modify it under the terms of
13  * the GNU General Public License as published by
14  * the Free Software Foundation; either version 2, or (at your option)
15  * any later version.
16  *
17  * This SCTP implementation is distributed in the hope that it
18  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
19  *                 ************************
20  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
21  * See the GNU General Public License for more details.
22  *
23  * You should have received a copy of the GNU General Public License
24  * along with GNU CC; see the file COPYING.  If not, write to
25  * the Free Software Foundation, 59 Temple Place - Suite 330,
26  * Boston, MA 02111-1307, USA.
27  *
28  * Please send any bug reports or fixes you make to the
29  * email address(es):
30  *    lksctp developers <lksctp-developers@lists.sourceforge.net>
31  *
32  * Or submit a bug report through the following website:
33  *    http://www.sf.net/projects/lksctp
34  *
35  * Written or modified by:
36  *    Le Yanqun             <yanqun.le@nokia.com>
37  *    Hui Huang             <hui.huang@nokia.com>
38  *    La Monte H.P. Yarroll <piggy@acm.org>
39  *    Sridhar Samudrala     <sri@us.ibm.com>
40  *    Jon Grimm             <jgrimm@us.ibm.com>
41  *    Ardelle Fan           <ardelle.fan@intel.com>
42  *
43  * Based on:
44  *      linux/net/ipv6/tcp_ipv6.c
45  *
46  * Any bugs reported given to us we will try to fix... any fixes shared will
47  * be incorporated into the next SCTP release.
48  */
49
50 #include <linux/module.h>
51 #include <linux/errno.h>
52 #include <linux/types.h>
53 #include <linux/socket.h>
54 #include <linux/sockios.h>
55 #include <linux/net.h>
56 #include <linux/in.h>
57 #include <linux/in6.h>
58 #include <linux/netdevice.h>
59 #include <linux/init.h>
60 #include <linux/ipsec.h>
61
62 #include <linux/ipv6.h>
63 #include <linux/icmpv6.h>
64 #include <linux/random.h>
65 #include <linux/seq_file.h>
66
67 #include <net/protocol.h>
68 #include <net/ndisc.h>
69 #include <net/ip.h>
70 #include <net/ipv6.h>
71 #include <net/transp_v6.h>
72 #include <net/addrconf.h>
73 #include <net/ip6_route.h>
74 #include <net/inet_common.h>
75 #include <net/inet_ecn.h>
76 #include <net/sctp/sctp.h>
77
78 #include <asm/uaccess.h>
79
80 /* Event handler for inet6 address addition/deletion events.
81  * The sctp_local_addr_list needs to be protocted by a spin lock since
82  * multiple notifiers (say IPv4 and IPv6) may be running at the same
83  * time and thus corrupt the list.
84  * The reader side is protected with RCU.
85  */
86 static int sctp_inet6addr_event(struct notifier_block *this, unsigned long ev,
87                                 void *ptr)
88 {
89         struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
90         struct sctp_sockaddr_entry *addr = NULL;
91         struct sctp_sockaddr_entry *temp;
92         int found = 0;
93
94         switch (ev) {
95         case NETDEV_UP:
96                 addr = kmalloc(sizeof(struct sctp_sockaddr_entry), GFP_ATOMIC);
97                 if (addr) {
98                         addr->a.v6.sin6_family = AF_INET6;
99                         addr->a.v6.sin6_port = 0;
100                         ipv6_addr_copy(&addr->a.v6.sin6_addr, &ifa->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 (addr->a.sa.sa_family == AF_INET6 &&
113                                         ipv6_addr_equal(&addr->a.v6.sin6_addr,
114                                                 &ifa->addr)) {
115                                 found = 1;
116                                 addr->valid = 0;
117                                 list_del_rcu(&addr->list);
118                                 break;
119                         }
120                 }
121                 spin_unlock_bh(&sctp_local_addr_lock);
122                 if (found)
123                         call_rcu(&addr->rcu, sctp_local_addr_free);
124                 break;
125         }
126
127         return NOTIFY_DONE;
128 }
129
130 static struct notifier_block sctp_inet6addr_notifier = {
131         .notifier_call = sctp_inet6addr_event,
132 };
133
134 /* ICMP error handler. */
135 SCTP_STATIC void sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
136                              u8 type, u8 code, int offset, __be32 info)
137 {
138         struct inet6_dev *idev;
139         struct sock *sk;
140         struct sctp_association *asoc;
141         struct sctp_transport *transport;
142         struct ipv6_pinfo *np;
143         sk_buff_data_t saveip, savesctp;
144         int err;
145
146         idev = in6_dev_get(skb->dev);
147
148         /* Fix up skb to look at the embedded net header. */
149         saveip   = skb->network_header;
150         savesctp = skb->transport_header;
151         skb_reset_network_header(skb);
152         skb_set_transport_header(skb, offset);
153         sk = sctp_err_lookup(AF_INET6, skb, sctp_hdr(skb), &asoc, &transport);
154         /* Put back, the original pointers. */
155         skb->network_header   = saveip;
156         skb->transport_header = savesctp;
157         if (!sk) {
158                 ICMP6_INC_STATS_BH(dev_net(skb->dev), idev, ICMP6_MIB_INERRORS);
159                 goto out;
160         }
161
162         /* Warning:  The sock lock is held.  Remember to call
163          * sctp_err_finish!
164          */
165
166         switch (type) {
167         case ICMPV6_PKT_TOOBIG:
168                 sctp_icmp_frag_needed(sk, asoc, transport, ntohl(info));
169                 goto out_unlock;
170         case ICMPV6_PARAMPROB:
171                 if (ICMPV6_UNK_NEXTHDR == code) {
172                         sctp_icmp_proto_unreachable(sk, asoc, transport);
173                         goto out_unlock;
174                 }
175                 break;
176         default:
177                 break;
178         }
179
180         np = inet6_sk(sk);
181         icmpv6_err_convert(type, code, &err);
182         if (!sock_owned_by_user(sk) && np->recverr) {
183                 sk->sk_err = err;
184                 sk->sk_error_report(sk);
185         } else {  /* Only an error on timeout */
186                 sk->sk_err_soft = err;
187         }
188
189 out_unlock:
190         sctp_err_finish(sk, asoc);
191 out:
192         if (likely(idev != NULL))
193                 in6_dev_put(idev);
194 }
195
196 /* Based on tcp_v6_xmit() in tcp_ipv6.c. */
197 static int sctp_v6_xmit(struct sk_buff *skb, struct sctp_transport *transport)
198 {
199         struct sock *sk = skb->sk;
200         struct ipv6_pinfo *np = inet6_sk(sk);
201         struct flowi fl;
202
203         memset(&fl, 0, sizeof(fl));
204
205         fl.proto = sk->sk_protocol;
206
207         /* Fill in the dest address from the route entry passed with the skb
208          * and the source address from the transport.
209          */
210         ipv6_addr_copy(&fl.fl6_dst, &transport->ipaddr.v6.sin6_addr);
211         ipv6_addr_copy(&fl.fl6_src, &transport->saddr.v6.sin6_addr);
212
213         fl.fl6_flowlabel = np->flow_label;
214         IP6_ECN_flow_xmit(sk, fl.fl6_flowlabel);
215         if (ipv6_addr_type(&fl.fl6_src) & IPV6_ADDR_LINKLOCAL)
216                 fl.oif = transport->saddr.v6.sin6_scope_id;
217         else
218                 fl.oif = sk->sk_bound_dev_if;
219
220         if (np->opt && np->opt->srcrt) {
221                 struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt;
222                 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
223         }
224
225         SCTP_DEBUG_PRINTK("%s: skb:%p, len:%d, src:%pI6 dst:%pI6\n",
226                           __func__, skb, skb->len,
227                           &fl.fl6_src, &fl.fl6_dst);
228
229         SCTP_INC_STATS(SCTP_MIB_OUTSCTPPACKS);
230
231         if (!(transport->param_flags & SPP_PMTUD_ENABLE))
232                 skb->local_df = 1;
233
234         return ip6_xmit(sk, skb, &fl, np->opt, 0);
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=%pI6 ", __func__, &fl.fl6_dst);
254
255         if (saddr) {
256                 ipv6_addr_copy(&fl.fl6_src, &saddr->v6.sin6_addr);
257                 SCTP_DEBUG_PRINTK("SRC=%pI6 - ", &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("rt6_dst:%pI6 rt6_src:%pI6\n",
265                         &rt->rt6i_dst.addr, &rt->rt6i_src.addr);
266                 return dst;
267         }
268         SCTP_DEBUG_PRINTK("NO ROUTE\n");
269         dst_release(dst);
270         return NULL;
271 }
272
273 /* Returns the number of consecutive initial bits that match in the 2 ipv6
274  * addresses.
275  */
276 static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
277                                          union sctp_addr *s2)
278 {
279         return ipv6_addr_diff(&s1->v6.sin6_addr, &s2->v6.sin6_addr);
280 }
281
282 /* Fills in the source address(saddr) based on the destination address(daddr)
283  * and asoc's bind address list.
284  */
285 static void sctp_v6_get_saddr(struct sctp_sock *sk,
286                               struct sctp_association *asoc,
287                               struct dst_entry *dst,
288                               union sctp_addr *daddr,
289                               union sctp_addr *saddr)
290 {
291         struct sctp_bind_addr *bp;
292         struct sctp_sockaddr_entry *laddr;
293         sctp_scope_t scope;
294         union sctp_addr *baddr = NULL;
295         __u8 matchlen = 0;
296         __u8 bmatchlen;
297
298         SCTP_DEBUG_PRINTK("%s: asoc:%p dst:%p daddr:%pI6 ",
299                           __func__, asoc, dst, &daddr->v6.sin6_addr);
300
301         if (!asoc) {
302                 ipv6_dev_get_saddr(sock_net(sctp_opt2sk(sk)),
303                                    dst ? ip6_dst_idev(dst)->dev : NULL,
304                                    &daddr->v6.sin6_addr,
305                                    inet6_sk(&sk->inet.sk)->srcprefs,
306                                    &saddr->v6.sin6_addr);
307                 SCTP_DEBUG_PRINTK("saddr from ipv6_get_saddr: %pI6\n",
308                                   &saddr->v6.sin6_addr);
309                 return;
310         }
311
312         scope = sctp_scope(daddr);
313
314         bp = &asoc->base.bind_addr;
315
316         /* Go through the bind address list and find the best source address
317          * that matches the scope of the destination address.
318          */
319         rcu_read_lock();
320         list_for_each_entry_rcu(laddr, &bp->address_list, list) {
321                 if (!laddr->valid)
322                         continue;
323                 if ((laddr->state == SCTP_ADDR_SRC) &&
324                     (laddr->a.sa.sa_family == AF_INET6) &&
325                     (scope <= sctp_scope(&laddr->a))) {
326                         bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a);
327                         if (!baddr || (matchlen < bmatchlen)) {
328                                 baddr = &laddr->a;
329                                 matchlen = bmatchlen;
330                         }
331                 }
332         }
333
334         if (baddr) {
335                 memcpy(saddr, baddr, sizeof(union sctp_addr));
336                 SCTP_DEBUG_PRINTK("saddr: %pI6\n", &saddr->v6.sin6_addr);
337         } else {
338                 printk(KERN_ERR "%s: asoc:%p Could not find a valid source "
339                        "address for the dest:%pI6\n",
340                        __func__, asoc, &daddr->v6.sin6_addr);
341         }
342
343         rcu_read_unlock();
344 }
345
346 /* Make a copy of all potential local addresses. */
347 static void sctp_v6_copy_addrlist(struct list_head *addrlist,
348                                   struct net_device *dev)
349 {
350         struct inet6_dev *in6_dev;
351         struct inet6_ifaddr *ifp;
352         struct sctp_sockaddr_entry *addr;
353
354         rcu_read_lock();
355         if ((in6_dev = __in6_dev_get(dev)) == NULL) {
356                 rcu_read_unlock();
357                 return;
358         }
359
360         read_lock_bh(&in6_dev->lock);
361         list_for_each_entry(ifp, &in6_dev->addr_list, if_list) {
362                 /* Add the address to the local list.  */
363                 addr = t_new(struct sctp_sockaddr_entry, GFP_ATOMIC);
364                 if (addr) {
365                         addr->a.v6.sin6_family = AF_INET6;
366                         addr->a.v6.sin6_port = 0;
367                         addr->a.v6.sin6_addr = ifp->addr;
368                         addr->a.v6.sin6_scope_id = dev->ifindex;
369                         addr->valid = 1;
370                         INIT_LIST_HEAD(&addr->list);
371                         list_add_tail(&addr->list, addrlist);
372                 }
373         }
374
375         read_unlock_bh(&in6_dev->lock);
376         rcu_read_unlock();
377 }
378
379 /* Initialize a sockaddr_storage from in incoming skb. */
380 static void sctp_v6_from_skb(union sctp_addr *addr,struct sk_buff *skb,
381                              int is_saddr)
382 {
383         void *from;
384         __be16 *port;
385         struct sctphdr *sh;
386
387         port = &addr->v6.sin6_port;
388         addr->v6.sin6_family = AF_INET6;
389         addr->v6.sin6_flowinfo = 0; /* FIXME */
390         addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif;
391
392         sh = sctp_hdr(skb);
393         if (is_saddr) {
394                 *port  = sh->source;
395                 from = &ipv6_hdr(skb)->saddr;
396         } else {
397                 *port = sh->dest;
398                 from = &ipv6_hdr(skb)->daddr;
399         }
400         ipv6_addr_copy(&addr->v6.sin6_addr, from);
401 }
402
403 /* Initialize an sctp_addr from a socket. */
404 static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk)
405 {
406         addr->v6.sin6_family = AF_INET6;
407         addr->v6.sin6_port = 0;
408         addr->v6.sin6_addr = inet6_sk(sk)->rcv_saddr;
409 }
410
411 /* Initialize sk->sk_rcv_saddr from sctp_addr. */
412 static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
413 {
414         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
415                 inet6_sk(sk)->rcv_saddr.s6_addr32[0] = 0;
416                 inet6_sk(sk)->rcv_saddr.s6_addr32[1] = 0;
417                 inet6_sk(sk)->rcv_saddr.s6_addr32[2] = htonl(0x0000ffff);
418                 inet6_sk(sk)->rcv_saddr.s6_addr32[3] =
419                         addr->v4.sin_addr.s_addr;
420         } else {
421                 inet6_sk(sk)->rcv_saddr = addr->v6.sin6_addr;
422         }
423 }
424
425 /* Initialize sk->sk_daddr from sctp_addr. */
426 static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
427 {
428         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
429                 inet6_sk(sk)->daddr.s6_addr32[0] = 0;
430                 inet6_sk(sk)->daddr.s6_addr32[1] = 0;
431                 inet6_sk(sk)->daddr.s6_addr32[2] = htonl(0x0000ffff);
432                 inet6_sk(sk)->daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
433         } else {
434                 inet6_sk(sk)->daddr = addr->v6.sin6_addr;
435         }
436 }
437
438 /* Initialize a sctp_addr from an address parameter. */
439 static void sctp_v6_from_addr_param(union sctp_addr *addr,
440                                     union sctp_addr_param *param,
441                                     __be16 port, int iif)
442 {
443         addr->v6.sin6_family = AF_INET6;
444         addr->v6.sin6_port = port;
445         addr->v6.sin6_flowinfo = 0; /* BUG */
446         ipv6_addr_copy(&addr->v6.sin6_addr, &param->v6.addr);
447         addr->v6.sin6_scope_id = iif;
448 }
449
450 /* Initialize an address parameter from a sctp_addr and return the length
451  * of the address parameter.
452  */
453 static int sctp_v6_to_addr_param(const union sctp_addr *addr,
454                                  union sctp_addr_param *param)
455 {
456         int length = sizeof(sctp_ipv6addr_param_t);
457
458         param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS;
459         param->v6.param_hdr.length = htons(length);
460         ipv6_addr_copy(&param->v6.addr, &addr->v6.sin6_addr);
461
462         return length;
463 }
464
465 /* Initialize a sctp_addr from a dst_entry. */
466 static void sctp_v6_dst_saddr(union sctp_addr *addr, struct dst_entry *dst,
467                               __be16 port)
468 {
469         struct rt6_info *rt = (struct rt6_info *)dst;
470         addr->sa.sa_family = AF_INET6;
471         addr->v6.sin6_port = port;
472         ipv6_addr_copy(&addr->v6.sin6_addr, &rt->rt6i_src.addr);
473 }
474
475 /* Compare addresses exactly.
476  * v4-mapped-v6 is also in consideration.
477  */
478 static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
479                             const union sctp_addr *addr2)
480 {
481         if (addr1->sa.sa_family != addr2->sa.sa_family) {
482                 if (addr1->sa.sa_family == AF_INET &&
483                     addr2->sa.sa_family == AF_INET6 &&
484                     ipv6_addr_v4mapped(&addr2->v6.sin6_addr)) {
485                         if (addr2->v6.sin6_port == addr1->v4.sin_port &&
486                             addr2->v6.sin6_addr.s6_addr32[3] ==
487                             addr1->v4.sin_addr.s_addr)
488                                 return 1;
489                 }
490                 if (addr2->sa.sa_family == AF_INET &&
491                     addr1->sa.sa_family == AF_INET6 &&
492                     ipv6_addr_v4mapped(&addr1->v6.sin6_addr)) {
493                         if (addr1->v6.sin6_port == addr2->v4.sin_port &&
494                             addr1->v6.sin6_addr.s6_addr32[3] ==
495                             addr2->v4.sin_addr.s_addr)
496                                 return 1;
497                 }
498                 return 0;
499         }
500         if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))
501                 return 0;
502         /* If this is a linklocal address, compare the scope_id. */
503         if (ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) {
504                 if (addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&
505                     (addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)) {
506                         return 0;
507                 }
508         }
509
510         return 1;
511 }
512
513 /* Initialize addr struct to INADDR_ANY. */
514 static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port)
515 {
516         memset(addr, 0x00, sizeof(union sctp_addr));
517         addr->v6.sin6_family = AF_INET6;
518         addr->v6.sin6_port = port;
519 }
520
521 /* Is this a wildcard address? */
522 static int sctp_v6_is_any(const union sctp_addr *addr)
523 {
524         return ipv6_addr_any(&addr->v6.sin6_addr);
525 }
526
527 /* Should this be available for binding?   */
528 static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp)
529 {
530         int type;
531         struct in6_addr *in6 = (struct in6_addr *)&addr->v6.sin6_addr;
532
533         type = ipv6_addr_type(in6);
534         if (IPV6_ADDR_ANY == type)
535                 return 1;
536         if (type == IPV6_ADDR_MAPPED) {
537                 if (sp && !sp->v4mapped)
538                         return 0;
539                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
540                         return 0;
541                 sctp_v6_map_v4(addr);
542                 return sctp_get_af_specific(AF_INET)->available(addr, sp);
543         }
544         if (!(type & IPV6_ADDR_UNICAST))
545                 return 0;
546
547         return ipv6_chk_addr(&init_net, in6, NULL, 0);
548 }
549
550 /* This function checks if the address is a valid address to be used for
551  * SCTP.
552  *
553  * Output:
554  * Return 0 - If the address is a non-unicast or an illegal address.
555  * Return 1 - If the address is a unicast.
556  */
557 static int sctp_v6_addr_valid(union sctp_addr *addr,
558                               struct sctp_sock *sp,
559                               const struct sk_buff *skb)
560 {
561         int ret = ipv6_addr_type(&addr->v6.sin6_addr);
562
563         /* Support v4-mapped-v6 address. */
564         if (ret == IPV6_ADDR_MAPPED) {
565                 /* Note: This routine is used in input, so v4-mapped-v6
566                  * are disallowed here when there is no sctp_sock.
567                  */
568                 if (!sp || !sp->v4mapped)
569                         return 0;
570                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
571                         return 0;
572                 sctp_v6_map_v4(addr);
573                 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb);
574         }
575
576         /* Is this a non-unicast address */
577         if (!(ret & IPV6_ADDR_UNICAST))
578                 return 0;
579
580         return 1;
581 }
582
583 /* What is the scope of 'addr'?  */
584 static sctp_scope_t sctp_v6_scope(union sctp_addr *addr)
585 {
586         int v6scope;
587         sctp_scope_t retval;
588
589         /* The IPv6 scope is really a set of bit fields.
590          * See IFA_* in <net/if_inet6.h>.  Map to a generic SCTP scope.
591          */
592
593         v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
594         switch (v6scope) {
595         case IFA_HOST:
596                 retval = SCTP_SCOPE_LOOPBACK;
597                 break;
598         case IFA_LINK:
599                 retval = SCTP_SCOPE_LINK;
600                 break;
601         case IFA_SITE:
602                 retval = SCTP_SCOPE_PRIVATE;
603                 break;
604         default:
605                 retval = SCTP_SCOPE_GLOBAL;
606                 break;
607         }
608
609         return retval;
610 }
611
612 /* Create and initialize a new sk for the socket to be returned by accept(). */
613 static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
614                                              struct sctp_association *asoc)
615 {
616         struct sock *newsk;
617         struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
618         struct sctp6_sock *newsctp6sk;
619
620         newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot);
621         if (!newsk)
622                 goto out;
623
624         sock_init_data(NULL, newsk);
625
626         sctp_copy_sock(newsk, sk, asoc);
627         sock_reset_flag(sk, SOCK_ZAPPED);
628
629         newsctp6sk = (struct sctp6_sock *)newsk;
630         inet_sk(newsk)->pinet6 = &newsctp6sk->inet6;
631
632         sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped;
633
634         newnp = inet6_sk(newsk);
635
636         memcpy(newnp, np, sizeof(struct ipv6_pinfo));
637
638         /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
639          * and getpeername().
640          */
641         sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
642
643         sk_refcnt_debug_inc(newsk);
644
645         if (newsk->sk_prot->init(newsk)) {
646                 sk_common_release(newsk);
647                 newsk = NULL;
648         }
649
650 out:
651         return newsk;
652 }
653
654 /* Map v4 address to mapped v6 address */
655 static void sctp_v6_addr_v4map(struct sctp_sock *sp, union sctp_addr *addr)
656 {
657         if (sp->v4mapped && AF_INET == addr->sa.sa_family)
658                 sctp_v4_map_v6(addr);
659 }
660
661 /* Where did this skb come from?  */
662 static int sctp_v6_skb_iif(const struct sk_buff *skb)
663 {
664         struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb;
665         return opt->iif;
666 }
667
668 /* Was this packet marked by Explicit Congestion Notification? */
669 static int sctp_v6_is_ce(const struct sk_buff *skb)
670 {
671         return *((__u32 *)(ipv6_hdr(skb))) & htonl(1 << 20);
672 }
673
674 /* Dump the v6 addr to the seq file. */
675 static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
676 {
677         seq_printf(seq, "%pI6 ", &addr->v6.sin6_addr);
678 }
679
680 static void sctp_v6_ecn_capable(struct sock *sk)
681 {
682         inet6_sk(sk)->tclass |= INET_ECN_ECT_0;
683 }
684
685 /* Initialize a PF_INET6 socket msg_name. */
686 static void sctp_inet6_msgname(char *msgname, int *addr_len)
687 {
688         struct sockaddr_in6 *sin6;
689
690         sin6 = (struct sockaddr_in6 *)msgname;
691         sin6->sin6_family = AF_INET6;
692         sin6->sin6_flowinfo = 0;
693         sin6->sin6_scope_id = 0; /*FIXME */
694         *addr_len = sizeof(struct sockaddr_in6);
695 }
696
697 /* Initialize a PF_INET msgname from a ulpevent. */
698 static void sctp_inet6_event_msgname(struct sctp_ulpevent *event,
699                                      char *msgname, int *addrlen)
700 {
701         struct sockaddr_in6 *sin6, *sin6from;
702
703         if (msgname) {
704                 union sctp_addr *addr;
705                 struct sctp_association *asoc;
706
707                 asoc = event->asoc;
708                 sctp_inet6_msgname(msgname, addrlen);
709                 sin6 = (struct sockaddr_in6 *)msgname;
710                 sin6->sin6_port = htons(asoc->peer.port);
711                 addr = &asoc->peer.primary_addr;
712
713                 /* Note: If we go to a common v6 format, this code
714                  * will change.
715                  */
716
717                 /* Map ipv4 address into v4-mapped-on-v6 address.  */
718                 if (sctp_sk(asoc->base.sk)->v4mapped &&
719                     AF_INET == addr->sa.sa_family) {
720                         sctp_v4_map_v6((union sctp_addr *)sin6);
721                         sin6->sin6_addr.s6_addr32[3] =
722                                 addr->v4.sin_addr.s_addr;
723                         return;
724                 }
725
726                 sin6from = &asoc->peer.primary_addr.v6;
727                 ipv6_addr_copy(&sin6->sin6_addr, &sin6from->sin6_addr);
728                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
729                         sin6->sin6_scope_id = sin6from->sin6_scope_id;
730         }
731 }
732
733 /* Initialize a msg_name from an inbound skb. */
734 static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname,
735                                    int *addr_len)
736 {
737         struct sctphdr *sh;
738         struct sockaddr_in6 *sin6;
739
740         if (msgname) {
741                 sctp_inet6_msgname(msgname, addr_len);
742                 sin6 = (struct sockaddr_in6 *)msgname;
743                 sh = sctp_hdr(skb);
744                 sin6->sin6_port = sh->source;
745
746                 /* Map ipv4 address into v4-mapped-on-v6 address. */
747                 if (sctp_sk(skb->sk)->v4mapped &&
748                     ip_hdr(skb)->version == 4) {
749                         sctp_v4_map_v6((union sctp_addr *)sin6);
750                         sin6->sin6_addr.s6_addr32[3] = ip_hdr(skb)->saddr;
751                         return;
752                 }
753
754                 /* Otherwise, just copy the v6 address. */
755                 ipv6_addr_copy(&sin6->sin6_addr, &ipv6_hdr(skb)->saddr);
756                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) {
757                         struct sctp_ulpevent *ev = sctp_skb2event(skb);
758                         sin6->sin6_scope_id = ev->iif;
759                 }
760         }
761 }
762
763 /* Do we support this AF? */
764 static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp)
765 {
766         switch (family) {
767         case AF_INET6:
768                 return 1;
769         /* v4-mapped-v6 addresses */
770         case AF_INET:
771                 if (!__ipv6_only_sock(sctp_opt2sk(sp)))
772                         return 1;
773         default:
774                 return 0;
775         }
776 }
777
778 /* Address matching with wildcards allowed.  This extra level
779  * of indirection lets us choose whether a PF_INET6 should
780  * disallow any v4 addresses if we so choose.
781  */
782 static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
783                                const union sctp_addr *addr2,
784                                struct sctp_sock *opt)
785 {
786         struct sctp_af *af1, *af2;
787         struct sock *sk = sctp_opt2sk(opt);
788
789         af1 = sctp_get_af_specific(addr1->sa.sa_family);
790         af2 = sctp_get_af_specific(addr2->sa.sa_family);
791
792         if (!af1 || !af2)
793                 return 0;
794
795         /* If the socket is IPv6 only, v4 addrs will not match */
796         if (__ipv6_only_sock(sk) && af1 != af2)
797                 return 0;
798
799         /* Today, wildcard AF_INET/AF_INET6. */
800         if (sctp_is_any(sk, addr1) || sctp_is_any(sk, addr2))
801                 return 1;
802
803         if (addr1->sa.sa_family != addr2->sa.sa_family)
804                 return 0;
805
806         return af1->cmp_addr(addr1, addr2);
807 }
808
809 /* Verify that the provided sockaddr looks bindable.   Common verification,
810  * has already been taken care of.
811  */
812 static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
813 {
814         struct sctp_af *af;
815
816         /* ASSERT: address family has already been verified. */
817         if (addr->sa.sa_family != AF_INET6)
818                 af = sctp_get_af_specific(addr->sa.sa_family);
819         else {
820                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
821                 struct net_device *dev;
822
823                 if (type & IPV6_ADDR_LINKLOCAL) {
824                         if (!addr->v6.sin6_scope_id)
825                                 return 0;
826                         rcu_read_lock();
827                         dev = dev_get_by_index_rcu(&init_net,
828                                                    addr->v6.sin6_scope_id);
829                         if (!dev ||
830                             !ipv6_chk_addr(&init_net, &addr->v6.sin6_addr,
831                                            dev, 0)) {
832                                 rcu_read_unlock();
833                                 return 0;
834                         }
835                         rcu_read_unlock();
836                 } else if (type == IPV6_ADDR_MAPPED) {
837                         if (!opt->v4mapped)
838                                 return 0;
839                 }
840
841                 af = opt->pf->af;
842         }
843         return af->available(addr, opt);
844 }
845
846 /* Verify that the provided sockaddr looks sendable.   Common verification,
847  * has already been taken care of.
848  */
849 static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
850 {
851         struct sctp_af *af = NULL;
852
853         /* ASSERT: address family has already been verified. */
854         if (addr->sa.sa_family != AF_INET6)
855                 af = sctp_get_af_specific(addr->sa.sa_family);
856         else {
857                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
858                 struct net_device *dev;
859
860                 if (type & IPV6_ADDR_LINKLOCAL) {
861                         if (!addr->v6.sin6_scope_id)
862                                 return 0;
863                         rcu_read_lock();
864                         dev = dev_get_by_index_rcu(&init_net,
865                                                    addr->v6.sin6_scope_id);
866                         rcu_read_unlock();
867                         if (!dev)
868                                 return 0;
869                 }
870                 af = opt->pf->af;
871         }
872
873         return af != NULL;
874 }
875
876 /* Fill in Supported Address Type information for INIT and INIT-ACK
877  * chunks.   Note: In the future, we may want to look at sock options
878  * to determine whether a PF_INET6 socket really wants to have IPV4
879  * addresses.
880  * Returns number of addresses supported.
881  */
882 static int sctp_inet6_supported_addrs(const struct sctp_sock *opt,
883                                       __be16 *types)
884 {
885         types[0] = SCTP_PARAM_IPV6_ADDRESS;
886         if (!opt || !ipv6_only_sock(sctp_opt2sk(opt))) {
887                 types[1] = SCTP_PARAM_IPV4_ADDRESS;
888                 return 2;
889         }
890         return 1;
891 }
892
893 static const struct proto_ops inet6_seqpacket_ops = {
894         .family            = PF_INET6,
895         .owner             = THIS_MODULE,
896         .release           = inet6_release,
897         .bind              = inet6_bind,
898         .connect           = inet_dgram_connect,
899         .socketpair        = sock_no_socketpair,
900         .accept            = inet_accept,
901         .getname           = inet6_getname,
902         .poll              = sctp_poll,
903         .ioctl             = inet6_ioctl,
904         .listen            = sctp_inet_listen,
905         .shutdown          = inet_shutdown,
906         .setsockopt        = sock_common_setsockopt,
907         .getsockopt        = sock_common_getsockopt,
908         .sendmsg           = inet_sendmsg,
909         .recvmsg           = sock_common_recvmsg,
910         .mmap              = sock_no_mmap,
911 #ifdef CONFIG_COMPAT
912         .compat_setsockopt = compat_sock_common_setsockopt,
913         .compat_getsockopt = compat_sock_common_getsockopt,
914 #endif
915 };
916
917 static struct inet_protosw sctpv6_seqpacket_protosw = {
918         .type          = SOCK_SEQPACKET,
919         .protocol      = IPPROTO_SCTP,
920         .prot          = &sctpv6_prot,
921         .ops           = &inet6_seqpacket_ops,
922         .no_check      = 0,
923         .flags         = SCTP_PROTOSW_FLAG
924 };
925 static struct inet_protosw sctpv6_stream_protosw = {
926         .type          = SOCK_STREAM,
927         .protocol      = IPPROTO_SCTP,
928         .prot          = &sctpv6_prot,
929         .ops           = &inet6_seqpacket_ops,
930         .no_check      = 0,
931         .flags         = SCTP_PROTOSW_FLAG,
932 };
933
934 static int sctp6_rcv(struct sk_buff *skb)
935 {
936         return sctp_rcv(skb) ? -1 : 0;
937 }
938
939 static const struct inet6_protocol sctpv6_protocol = {
940         .handler      = sctp6_rcv,
941         .err_handler  = sctp_v6_err,
942         .flags        = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
943 };
944
945 static struct sctp_af sctp_af_inet6 = {
946         .sa_family         = AF_INET6,
947         .sctp_xmit         = sctp_v6_xmit,
948         .setsockopt        = ipv6_setsockopt,
949         .getsockopt        = ipv6_getsockopt,
950         .get_dst           = sctp_v6_get_dst,
951         .get_saddr         = sctp_v6_get_saddr,
952         .copy_addrlist     = sctp_v6_copy_addrlist,
953         .from_skb          = sctp_v6_from_skb,
954         .from_sk           = sctp_v6_from_sk,
955         .to_sk_saddr       = sctp_v6_to_sk_saddr,
956         .to_sk_daddr       = sctp_v6_to_sk_daddr,
957         .from_addr_param   = sctp_v6_from_addr_param,
958         .to_addr_param     = sctp_v6_to_addr_param,
959         .dst_saddr         = sctp_v6_dst_saddr,
960         .cmp_addr          = sctp_v6_cmp_addr,
961         .scope             = sctp_v6_scope,
962         .addr_valid        = sctp_v6_addr_valid,
963         .inaddr_any        = sctp_v6_inaddr_any,
964         .is_any            = sctp_v6_is_any,
965         .available         = sctp_v6_available,
966         .skb_iif           = sctp_v6_skb_iif,
967         .is_ce             = sctp_v6_is_ce,
968         .seq_dump_addr     = sctp_v6_seq_dump_addr,
969         .ecn_capable       = sctp_v6_ecn_capable,
970         .net_header_len    = sizeof(struct ipv6hdr),
971         .sockaddr_len      = sizeof(struct sockaddr_in6),
972 #ifdef CONFIG_COMPAT
973         .compat_setsockopt = compat_ipv6_setsockopt,
974         .compat_getsockopt = compat_ipv6_getsockopt,
975 #endif
976 };
977
978 static struct sctp_pf sctp_pf_inet6 = {
979         .event_msgname = sctp_inet6_event_msgname,
980         .skb_msgname   = sctp_inet6_skb_msgname,
981         .af_supported  = sctp_inet6_af_supported,
982         .cmp_addr      = sctp_inet6_cmp_addr,
983         .bind_verify   = sctp_inet6_bind_verify,
984         .send_verify   = sctp_inet6_send_verify,
985         .supported_addrs = sctp_inet6_supported_addrs,
986         .create_accept_sk = sctp_v6_create_accept_sk,
987         .addr_v4map    = sctp_v6_addr_v4map,
988         .af            = &sctp_af_inet6,
989 };
990
991 /* Initialize IPv6 support and register with socket layer.  */
992 void sctp_v6_pf_init(void)
993 {
994         /* Register the SCTP specific PF_INET6 functions. */
995         sctp_register_pf(&sctp_pf_inet6, PF_INET6);
996
997         /* Register the SCTP specific AF_INET6 functions. */
998         sctp_register_af(&sctp_af_inet6);
999 }
1000
1001 void sctp_v6_pf_exit(void)
1002 {
1003         list_del(&sctp_af_inet6.list);
1004 }
1005
1006 /* Initialize IPv6 support and register with socket layer.  */
1007 int sctp_v6_protosw_init(void)
1008 {
1009         int rc;
1010
1011         rc = proto_register(&sctpv6_prot, 1);
1012         if (rc)
1013                 return rc;
1014
1015         /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
1016         inet6_register_protosw(&sctpv6_seqpacket_protosw);
1017         inet6_register_protosw(&sctpv6_stream_protosw);
1018
1019         return 0;
1020 }
1021
1022 void sctp_v6_protosw_exit(void)
1023 {
1024         inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
1025         inet6_unregister_protosw(&sctpv6_stream_protosw);
1026         proto_unregister(&sctpv6_prot);
1027 }
1028
1029
1030 /* Register with inet6 layer. */
1031 int sctp_v6_add_protocol(void)
1032 {
1033         /* Register notifier for inet6 address additions/deletions. */
1034         register_inet6addr_notifier(&sctp_inet6addr_notifier);
1035
1036         if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
1037                 return -EAGAIN;
1038
1039         return 0;
1040 }
1041
1042 /* Unregister with inet6 layer. */
1043 void sctp_v6_del_protocol(void)
1044 {
1045         inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
1046         unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
1047 }