net: replace ipfragok with skb->local_df
[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 #include <linux/slab.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/ndisc.h>
70 #include <net/ip.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 /* Event handler for inet6 address addition/deletion events.
82  * The sctp_local_addr_list needs to be protocted by a spin lock since
83  * multiple notifiers (say IPv4 and IPv6) may be running at the same
84  * time and thus corrupt the list.
85  * The reader side is protected with RCU.
86  */
87 static int sctp_inet6addr_event(struct notifier_block *this, unsigned long ev,
88                                 void *ptr)
89 {
90         struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
91         struct sctp_sockaddr_entry *addr = NULL;
92         struct sctp_sockaddr_entry *temp;
93         int found = 0;
94
95         switch (ev) {
96         case NETDEV_UP:
97                 addr = kmalloc(sizeof(struct sctp_sockaddr_entry), GFP_ATOMIC);
98                 if (addr) {
99                         addr->a.v6.sin6_family = AF_INET6;
100                         addr->a.v6.sin6_port = 0;
101                         ipv6_addr_copy(&addr->a.v6.sin6_addr, &ifa->addr);
102                         addr->a.v6.sin6_scope_id = ifa->idev->dev->ifindex;
103                         addr->valid = 1;
104                         spin_lock_bh(&sctp_local_addr_lock);
105                         list_add_tail_rcu(&addr->list, &sctp_local_addr_list);
106                         spin_unlock_bh(&sctp_local_addr_lock);
107                 }
108                 break;
109         case NETDEV_DOWN:
110                 spin_lock_bh(&sctp_local_addr_lock);
111                 list_for_each_entry_safe(addr, temp,
112                                         &sctp_local_addr_list, list) {
113                         if (addr->a.sa.sa_family == AF_INET6 &&
114                                         ipv6_addr_equal(&addr->a.v6.sin6_addr,
115                                                 &ifa->addr)) {
116                                 found = 1;
117                                 addr->valid = 0;
118                                 list_del_rcu(&addr->list);
119                                 break;
120                         }
121                 }
122                 spin_unlock_bh(&sctp_local_addr_lock);
123                 if (found)
124                         call_rcu(&addr->rcu, sctp_local_addr_free);
125                 break;
126         }
127
128         return NOTIFY_DONE;
129 }
130
131 static struct notifier_block sctp_inet6addr_notifier = {
132         .notifier_call = sctp_inet6addr_event,
133 };
134
135 /* ICMP error handler. */
136 SCTP_STATIC void sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
137                              u8 type, u8 code, int offset, __be32 info)
138 {
139         struct inet6_dev *idev;
140         struct sock *sk;
141         struct sctp_association *asoc;
142         struct sctp_transport *transport;
143         struct ipv6_pinfo *np;
144         sk_buff_data_t saveip, savesctp;
145         int err;
146
147         idev = in6_dev_get(skb->dev);
148
149         /* Fix up skb to look at the embedded net header. */
150         saveip   = skb->network_header;
151         savesctp = skb->transport_header;
152         skb_reset_network_header(skb);
153         skb_set_transport_header(skb, offset);
154         sk = sctp_err_lookup(AF_INET6, skb, sctp_hdr(skb), &asoc, &transport);
155         /* Put back, the original pointers. */
156         skb->network_header   = saveip;
157         skb->transport_header = savesctp;
158         if (!sk) {
159                 ICMP6_INC_STATS_BH(dev_net(skb->dev), idev, ICMP6_MIB_INERRORS);
160                 goto out;
161         }
162
163         /* Warning:  The sock lock is held.  Remember to call
164          * sctp_err_finish!
165          */
166
167         switch (type) {
168         case ICMPV6_PKT_TOOBIG:
169                 sctp_icmp_frag_needed(sk, asoc, transport, ntohl(info));
170                 goto out_unlock;
171         case ICMPV6_PARAMPROB:
172                 if (ICMPV6_UNK_NEXTHDR == code) {
173                         sctp_icmp_proto_unreachable(sk, asoc, transport);
174                         goto out_unlock;
175                 }
176                 break;
177         default:
178                 break;
179         }
180
181         np = inet6_sk(sk);
182         icmpv6_err_convert(type, code, &err);
183         if (!sock_owned_by_user(sk) && np->recverr) {
184                 sk->sk_err = err;
185                 sk->sk_error_report(sk);
186         } else {  /* Only an error on timeout */
187                 sk->sk_err_soft = err;
188         }
189
190 out_unlock:
191         sctp_err_finish(sk, asoc);
192 out:
193         if (likely(idev != NULL))
194                 in6_dev_put(idev);
195 }
196
197 /* Based on tcp_v6_xmit() in tcp_ipv6.c. */
198 static int sctp_v6_xmit(struct sk_buff *skb, struct sctp_transport *transport)
199 {
200         struct sock *sk = skb->sk;
201         struct ipv6_pinfo *np = inet6_sk(sk);
202         struct flowi fl;
203
204         memset(&fl, 0, sizeof(fl));
205
206         fl.proto = sk->sk_protocol;
207
208         /* Fill in the dest address from the route entry passed with the skb
209          * and the source address from the transport.
210          */
211         ipv6_addr_copy(&fl.fl6_dst, &transport->ipaddr.v6.sin6_addr);
212         ipv6_addr_copy(&fl.fl6_src, &transport->saddr.v6.sin6_addr);
213
214         fl.fl6_flowlabel = np->flow_label;
215         IP6_ECN_flow_xmit(sk, fl.fl6_flowlabel);
216         if (ipv6_addr_type(&fl.fl6_src) & IPV6_ADDR_LINKLOCAL)
217                 fl.oif = transport->saddr.v6.sin6_scope_id;
218         else
219                 fl.oif = sk->sk_bound_dev_if;
220
221         if (np->opt && np->opt->srcrt) {
222                 struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt;
223                 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
224         }
225
226         SCTP_DEBUG_PRINTK("%s: skb:%p, len:%d, src:%pI6 dst:%pI6\n",
227                           __func__, skb, skb->len,
228                           &fl.fl6_src, &fl.fl6_dst);
229
230         SCTP_INC_STATS(SCTP_MIB_OUTSCTPPACKS);
231
232         if (!(transport->param_flags & SPP_PMTUD_ENABLE))
233                 skb->local_df = 1;
234
235         return ip6_xmit(sk, skb, &fl, np->opt);
236 }
237
238 /* Returns the dst cache entry for the given source and destination ip
239  * addresses.
240  */
241 static struct dst_entry *sctp_v6_get_dst(struct sctp_association *asoc,
242                                          union sctp_addr *daddr,
243                                          union sctp_addr *saddr)
244 {
245         struct dst_entry *dst;
246         struct flowi fl;
247
248         memset(&fl, 0, sizeof(fl));
249         ipv6_addr_copy(&fl.fl6_dst, &daddr->v6.sin6_addr);
250         if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
251                 fl.oif = daddr->v6.sin6_scope_id;
252
253
254         SCTP_DEBUG_PRINTK("%s: DST=%pI6 ", __func__, &fl.fl6_dst);
255
256         if (saddr) {
257                 ipv6_addr_copy(&fl.fl6_src, &saddr->v6.sin6_addr);
258                 SCTP_DEBUG_PRINTK("SRC=%pI6 - ", &fl.fl6_src);
259         }
260
261         dst = ip6_route_output(&init_net, NULL, &fl);
262         if (!dst->error) {
263                 struct rt6_info *rt;
264                 rt = (struct rt6_info *)dst;
265                 SCTP_DEBUG_PRINTK("rt6_dst:%pI6 rt6_src:%pI6\n",
266                         &rt->rt6i_dst.addr, &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         return ipv6_addr_diff(&s1->v6.sin6_addr, &s2->v6.sin6_addr);
281 }
282
283 /* Fills in the source address(saddr) based on the destination address(daddr)
284  * and asoc's bind address list.
285  */
286 static void sctp_v6_get_saddr(struct sctp_sock *sk,
287                               struct sctp_association *asoc,
288                               struct dst_entry *dst,
289                               union sctp_addr *daddr,
290                               union sctp_addr *saddr)
291 {
292         struct sctp_bind_addr *bp;
293         struct sctp_sockaddr_entry *laddr;
294         sctp_scope_t scope;
295         union sctp_addr *baddr = NULL;
296         __u8 matchlen = 0;
297         __u8 bmatchlen;
298
299         SCTP_DEBUG_PRINTK("%s: asoc:%p dst:%p daddr:%pI6 ",
300                           __func__, asoc, dst, &daddr->v6.sin6_addr);
301
302         if (!asoc) {
303                 ipv6_dev_get_saddr(sock_net(sctp_opt2sk(sk)),
304                                    dst ? ip6_dst_idev(dst)->dev : NULL,
305                                    &daddr->v6.sin6_addr,
306                                    inet6_sk(&sk->inet.sk)->srcprefs,
307                                    &saddr->v6.sin6_addr);
308                 SCTP_DEBUG_PRINTK("saddr from ipv6_get_saddr: %pI6\n",
309                                   &saddr->v6.sin6_addr);
310                 return;
311         }
312
313         scope = sctp_scope(daddr);
314
315         bp = &asoc->base.bind_addr;
316
317         /* Go through the bind address list and find the best source address
318          * that matches the scope of the destination address.
319          */
320         rcu_read_lock();
321         list_for_each_entry_rcu(laddr, &bp->address_list, list) {
322                 if (!laddr->valid)
323                         continue;
324                 if ((laddr->state == SCTP_ADDR_SRC) &&
325                     (laddr->a.sa.sa_family == AF_INET6) &&
326                     (scope <= sctp_scope(&laddr->a))) {
327                         bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a);
328                         if (!baddr || (matchlen < bmatchlen)) {
329                                 baddr = &laddr->a;
330                                 matchlen = bmatchlen;
331                         }
332                 }
333         }
334
335         if (baddr) {
336                 memcpy(saddr, baddr, sizeof(union sctp_addr));
337                 SCTP_DEBUG_PRINTK("saddr: %pI6\n", &saddr->v6.sin6_addr);
338         } else {
339                 printk(KERN_ERR "%s: asoc:%p Could not find a valid source "
340                        "address for the dest:%pI6\n",
341                        __func__, asoc, &daddr->v6.sin6_addr);
342         }
343
344         rcu_read_unlock();
345 }
346
347 /* Make a copy of all potential local addresses. */
348 static void sctp_v6_copy_addrlist(struct list_head *addrlist,
349                                   struct net_device *dev)
350 {
351         struct inet6_dev *in6_dev;
352         struct inet6_ifaddr *ifp;
353         struct sctp_sockaddr_entry *addr;
354
355         rcu_read_lock();
356         if ((in6_dev = __in6_dev_get(dev)) == NULL) {
357                 rcu_read_unlock();
358                 return;
359         }
360
361         read_lock_bh(&in6_dev->lock);
362         list_for_each_entry(ifp, &in6_dev->addr_list, if_list) {
363                 /* Add the address to the local list.  */
364                 addr = t_new(struct sctp_sockaddr_entry, GFP_ATOMIC);
365                 if (addr) {
366                         addr->a.v6.sin6_family = AF_INET6;
367                         addr->a.v6.sin6_port = 0;
368                         ipv6_addr_copy(&addr->a.v6.sin6_addr, &ifp->addr);
369                         addr->a.v6.sin6_scope_id = dev->ifindex;
370                         addr->valid = 1;
371                         INIT_LIST_HEAD(&addr->list);
372                         list_add_tail(&addr->list, addrlist);
373                 }
374         }
375
376         read_unlock_bh(&in6_dev->lock);
377         rcu_read_unlock();
378 }
379
380 /* Initialize a sockaddr_storage from in incoming skb. */
381 static void sctp_v6_from_skb(union sctp_addr *addr,struct sk_buff *skb,
382                              int is_saddr)
383 {
384         void *from;
385         __be16 *port;
386         struct sctphdr *sh;
387
388         port = &addr->v6.sin6_port;
389         addr->v6.sin6_family = AF_INET6;
390         addr->v6.sin6_flowinfo = 0; /* FIXME */
391         addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif;
392
393         sh = sctp_hdr(skb);
394         if (is_saddr) {
395                 *port  = sh->source;
396                 from = &ipv6_hdr(skb)->saddr;
397         } else {
398                 *port = sh->dest;
399                 from = &ipv6_hdr(skb)->daddr;
400         }
401         ipv6_addr_copy(&addr->v6.sin6_addr, from);
402 }
403
404 /* Initialize an sctp_addr from a socket. */
405 static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk)
406 {
407         addr->v6.sin6_family = AF_INET6;
408         addr->v6.sin6_port = 0;
409         ipv6_addr_copy(&addr->v6.sin6_addr, &inet6_sk(sk)->rcv_saddr);
410 }
411
412 /* Initialize sk->sk_rcv_saddr from sctp_addr. */
413 static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
414 {
415         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
416                 inet6_sk(sk)->rcv_saddr.s6_addr32[0] = 0;
417                 inet6_sk(sk)->rcv_saddr.s6_addr32[1] = 0;
418                 inet6_sk(sk)->rcv_saddr.s6_addr32[2] = htonl(0x0000ffff);
419                 inet6_sk(sk)->rcv_saddr.s6_addr32[3] =
420                         addr->v4.sin_addr.s_addr;
421         } else {
422                 ipv6_addr_copy(&inet6_sk(sk)->rcv_saddr, &addr->v6.sin6_addr);
423         }
424 }
425
426 /* Initialize sk->sk_daddr from sctp_addr. */
427 static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
428 {
429         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
430                 inet6_sk(sk)->daddr.s6_addr32[0] = 0;
431                 inet6_sk(sk)->daddr.s6_addr32[1] = 0;
432                 inet6_sk(sk)->daddr.s6_addr32[2] = htonl(0x0000ffff);
433                 inet6_sk(sk)->daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
434         } else {
435                 ipv6_addr_copy(&inet6_sk(sk)->daddr, &addr->v6.sin6_addr);
436         }
437 }
438
439 /* Initialize a sctp_addr from an address parameter. */
440 static void sctp_v6_from_addr_param(union sctp_addr *addr,
441                                     union sctp_addr_param *param,
442                                     __be16 port, int iif)
443 {
444         addr->v6.sin6_family = AF_INET6;
445         addr->v6.sin6_port = port;
446         addr->v6.sin6_flowinfo = 0; /* BUG */
447         ipv6_addr_copy(&addr->v6.sin6_addr, &param->v6.addr);
448         addr->v6.sin6_scope_id = iif;
449 }
450
451 /* Initialize an address parameter from a sctp_addr and return the length
452  * of the address parameter.
453  */
454 static int sctp_v6_to_addr_param(const union sctp_addr *addr,
455                                  union sctp_addr_param *param)
456 {
457         int length = sizeof(sctp_ipv6addr_param_t);
458
459         param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS;
460         param->v6.param_hdr.length = htons(length);
461         ipv6_addr_copy(&param->v6.addr, &addr->v6.sin6_addr);
462
463         return length;
464 }
465
466 /* Initialize a sctp_addr from a dst_entry. */
467 static void sctp_v6_dst_saddr(union sctp_addr *addr, struct dst_entry *dst,
468                               __be16 port)
469 {
470         struct rt6_info *rt = (struct rt6_info *)dst;
471         addr->sa.sa_family = AF_INET6;
472         addr->v6.sin6_port = port;
473         ipv6_addr_copy(&addr->v6.sin6_addr, &rt->rt6i_src.addr);
474 }
475
476 /* Compare addresses exactly.
477  * v4-mapped-v6 is also in consideration.
478  */
479 static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
480                             const union sctp_addr *addr2)
481 {
482         if (addr1->sa.sa_family != addr2->sa.sa_family) {
483                 if (addr1->sa.sa_family == AF_INET &&
484                     addr2->sa.sa_family == AF_INET6 &&
485                     ipv6_addr_v4mapped(&addr2->v6.sin6_addr)) {
486                         if (addr2->v6.sin6_port == addr1->v4.sin_port &&
487                             addr2->v6.sin6_addr.s6_addr32[3] ==
488                             addr1->v4.sin_addr.s_addr)
489                                 return 1;
490                 }
491                 if (addr2->sa.sa_family == AF_INET &&
492                     addr1->sa.sa_family == AF_INET6 &&
493                     ipv6_addr_v4mapped(&addr1->v6.sin6_addr)) {
494                         if (addr1->v6.sin6_port == addr2->v4.sin_port &&
495                             addr1->v6.sin6_addr.s6_addr32[3] ==
496                             addr2->v4.sin_addr.s_addr)
497                                 return 1;
498                 }
499                 return 0;
500         }
501         if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))
502                 return 0;
503         /* If this is a linklocal address, compare the scope_id. */
504         if (ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) {
505                 if (addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&
506                     (addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)) {
507                         return 0;
508                 }
509         }
510
511         return 1;
512 }
513
514 /* Initialize addr struct to INADDR_ANY. */
515 static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port)
516 {
517         memset(addr, 0x00, sizeof(union sctp_addr));
518         addr->v6.sin6_family = AF_INET6;
519         addr->v6.sin6_port = port;
520 }
521
522 /* Is this a wildcard address? */
523 static int sctp_v6_is_any(const union sctp_addr *addr)
524 {
525         return ipv6_addr_any(&addr->v6.sin6_addr);
526 }
527
528 /* Should this be available for binding?   */
529 static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp)
530 {
531         int type;
532         struct in6_addr *in6 = (struct in6_addr *)&addr->v6.sin6_addr;
533
534         type = ipv6_addr_type(in6);
535         if (IPV6_ADDR_ANY == type)
536                 return 1;
537         if (type == IPV6_ADDR_MAPPED) {
538                 if (sp && !sp->v4mapped)
539                         return 0;
540                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
541                         return 0;
542                 sctp_v6_map_v4(addr);
543                 return sctp_get_af_specific(AF_INET)->available(addr, sp);
544         }
545         if (!(type & IPV6_ADDR_UNICAST))
546                 return 0;
547
548         return ipv6_chk_addr(&init_net, in6, NULL, 0);
549 }
550
551 /* This function checks if the address is a valid address to be used for
552  * SCTP.
553  *
554  * Output:
555  * Return 0 - If the address is a non-unicast or an illegal address.
556  * Return 1 - If the address is a unicast.
557  */
558 static int sctp_v6_addr_valid(union sctp_addr *addr,
559                               struct sctp_sock *sp,
560                               const struct sk_buff *skb)
561 {
562         int ret = ipv6_addr_type(&addr->v6.sin6_addr);
563
564         /* Support v4-mapped-v6 address. */
565         if (ret == IPV6_ADDR_MAPPED) {
566                 /* Note: This routine is used in input, so v4-mapped-v6
567                  * are disallowed here when there is no sctp_sock.
568                  */
569                 if (!sp || !sp->v4mapped)
570                         return 0;
571                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
572                         return 0;
573                 sctp_v6_map_v4(addr);
574                 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb);
575         }
576
577         /* Is this a non-unicast address */
578         if (!(ret & IPV6_ADDR_UNICAST))
579                 return 0;
580
581         return 1;
582 }
583
584 /* What is the scope of 'addr'?  */
585 static sctp_scope_t sctp_v6_scope(union sctp_addr *addr)
586 {
587         int v6scope;
588         sctp_scope_t retval;
589
590         /* The IPv6 scope is really a set of bit fields.
591          * See IFA_* in <net/if_inet6.h>.  Map to a generic SCTP scope.
592          */
593
594         v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
595         switch (v6scope) {
596         case IFA_HOST:
597                 retval = SCTP_SCOPE_LOOPBACK;
598                 break;
599         case IFA_LINK:
600                 retval = SCTP_SCOPE_LINK;
601                 break;
602         case IFA_SITE:
603                 retval = SCTP_SCOPE_PRIVATE;
604                 break;
605         default:
606                 retval = SCTP_SCOPE_GLOBAL;
607                 break;
608         }
609
610         return retval;
611 }
612
613 /* Create and initialize a new sk for the socket to be returned by accept(). */
614 static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
615                                              struct sctp_association *asoc)
616 {
617         struct sock *newsk;
618         struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
619         struct sctp6_sock *newsctp6sk;
620
621         newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot);
622         if (!newsk)
623                 goto out;
624
625         sock_init_data(NULL, newsk);
626
627         sctp_copy_sock(newsk, sk, asoc);
628         sock_reset_flag(sk, SOCK_ZAPPED);
629
630         newsctp6sk = (struct sctp6_sock *)newsk;
631         inet_sk(newsk)->pinet6 = &newsctp6sk->inet6;
632
633         sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped;
634
635         newnp = inet6_sk(newsk);
636
637         memcpy(newnp, np, sizeof(struct ipv6_pinfo));
638
639         /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
640          * and getpeername().
641          */
642         sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
643
644         sk_refcnt_debug_inc(newsk);
645
646         if (newsk->sk_prot->init(newsk)) {
647                 sk_common_release(newsk);
648                 newsk = NULL;
649         }
650
651 out:
652         return newsk;
653 }
654
655 /* Map v4 address to mapped v6 address */
656 static void sctp_v6_addr_v4map(struct sctp_sock *sp, union sctp_addr *addr)
657 {
658         if (sp->v4mapped && AF_INET == addr->sa.sa_family)
659                 sctp_v4_map_v6(addr);
660 }
661
662 /* Where did this skb come from?  */
663 static int sctp_v6_skb_iif(const struct sk_buff *skb)
664 {
665         struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb;
666         return opt->iif;
667 }
668
669 /* Was this packet marked by Explicit Congestion Notification? */
670 static int sctp_v6_is_ce(const struct sk_buff *skb)
671 {
672         return *((__u32 *)(ipv6_hdr(skb))) & htonl(1 << 20);
673 }
674
675 /* Dump the v6 addr to the seq file. */
676 static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
677 {
678         seq_printf(seq, "%pI6 ", &addr->v6.sin6_addr);
679 }
680
681 static void sctp_v6_ecn_capable(struct sock *sk)
682 {
683         inet6_sk(sk)->tclass |= INET_ECN_ECT_0;
684 }
685
686 /* Initialize a PF_INET6 socket msg_name. */
687 static void sctp_inet6_msgname(char *msgname, int *addr_len)
688 {
689         struct sockaddr_in6 *sin6;
690
691         sin6 = (struct sockaddr_in6 *)msgname;
692         sin6->sin6_family = AF_INET6;
693         sin6->sin6_flowinfo = 0;
694         sin6->sin6_scope_id = 0; /*FIXME */
695         *addr_len = sizeof(struct sockaddr_in6);
696 }
697
698 /* Initialize a PF_INET msgname from a ulpevent. */
699 static void sctp_inet6_event_msgname(struct sctp_ulpevent *event,
700                                      char *msgname, int *addrlen)
701 {
702         struct sockaddr_in6 *sin6, *sin6from;
703
704         if (msgname) {
705                 union sctp_addr *addr;
706                 struct sctp_association *asoc;
707
708                 asoc = event->asoc;
709                 sctp_inet6_msgname(msgname, addrlen);
710                 sin6 = (struct sockaddr_in6 *)msgname;
711                 sin6->sin6_port = htons(asoc->peer.port);
712                 addr = &asoc->peer.primary_addr;
713
714                 /* Note: If we go to a common v6 format, this code
715                  * will change.
716                  */
717
718                 /* Map ipv4 address into v4-mapped-on-v6 address.  */
719                 if (sctp_sk(asoc->base.sk)->v4mapped &&
720                     AF_INET == addr->sa.sa_family) {
721                         sctp_v4_map_v6((union sctp_addr *)sin6);
722                         sin6->sin6_addr.s6_addr32[3] =
723                                 addr->v4.sin_addr.s_addr;
724                         return;
725                 }
726
727                 sin6from = &asoc->peer.primary_addr.v6;
728                 ipv6_addr_copy(&sin6->sin6_addr, &sin6from->sin6_addr);
729                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
730                         sin6->sin6_scope_id = sin6from->sin6_scope_id;
731         }
732 }
733
734 /* Initialize a msg_name from an inbound skb. */
735 static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname,
736                                    int *addr_len)
737 {
738         struct sctphdr *sh;
739         struct sockaddr_in6 *sin6;
740
741         if (msgname) {
742                 sctp_inet6_msgname(msgname, addr_len);
743                 sin6 = (struct sockaddr_in6 *)msgname;
744                 sh = sctp_hdr(skb);
745                 sin6->sin6_port = sh->source;
746
747                 /* Map ipv4 address into v4-mapped-on-v6 address. */
748                 if (sctp_sk(skb->sk)->v4mapped &&
749                     ip_hdr(skb)->version == 4) {
750                         sctp_v4_map_v6((union sctp_addr *)sin6);
751                         sin6->sin6_addr.s6_addr32[3] = ip_hdr(skb)->saddr;
752                         return;
753                 }
754
755                 /* Otherwise, just copy the v6 address. */
756                 ipv6_addr_copy(&sin6->sin6_addr, &ipv6_hdr(skb)->saddr);
757                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) {
758                         struct sctp_ulpevent *ev = sctp_skb2event(skb);
759                         sin6->sin6_scope_id = ev->iif;
760                 }
761         }
762 }
763
764 /* Do we support this AF? */
765 static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp)
766 {
767         switch (family) {
768         case AF_INET6:
769                 return 1;
770         /* v4-mapped-v6 addresses */
771         case AF_INET:
772                 if (!__ipv6_only_sock(sctp_opt2sk(sp)))
773                         return 1;
774         default:
775                 return 0;
776         }
777 }
778
779 /* Address matching with wildcards allowed.  This extra level
780  * of indirection lets us choose whether a PF_INET6 should
781  * disallow any v4 addresses if we so choose.
782  */
783 static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
784                                const union sctp_addr *addr2,
785                                struct sctp_sock *opt)
786 {
787         struct sctp_af *af1, *af2;
788         struct sock *sk = sctp_opt2sk(opt);
789
790         af1 = sctp_get_af_specific(addr1->sa.sa_family);
791         af2 = sctp_get_af_specific(addr2->sa.sa_family);
792
793         if (!af1 || !af2)
794                 return 0;
795
796         /* If the socket is IPv6 only, v4 addrs will not match */
797         if (__ipv6_only_sock(sk) && af1 != af2)
798                 return 0;
799
800         /* Today, wildcard AF_INET/AF_INET6. */
801         if (sctp_is_any(sk, addr1) || sctp_is_any(sk, addr2))
802                 return 1;
803
804         if (addr1->sa.sa_family != addr2->sa.sa_family)
805                 return 0;
806
807         return af1->cmp_addr(addr1, addr2);
808 }
809
810 /* Verify that the provided sockaddr looks bindable.   Common verification,
811  * has already been taken care of.
812  */
813 static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
814 {
815         struct sctp_af *af;
816
817         /* ASSERT: address family has already been verified. */
818         if (addr->sa.sa_family != AF_INET6)
819                 af = sctp_get_af_specific(addr->sa.sa_family);
820         else {
821                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
822                 struct net_device *dev;
823
824                 if (type & IPV6_ADDR_LINKLOCAL) {
825                         if (!addr->v6.sin6_scope_id)
826                                 return 0;
827                         rcu_read_lock();
828                         dev = dev_get_by_index_rcu(&init_net,
829                                                    addr->v6.sin6_scope_id);
830                         if (!dev ||
831                             !ipv6_chk_addr(&init_net, &addr->v6.sin6_addr,
832                                            dev, 0)) {
833                                 rcu_read_unlock();
834                                 return 0;
835                         }
836                         rcu_read_unlock();
837                 } else if (type == IPV6_ADDR_MAPPED) {
838                         if (!opt->v4mapped)
839                                 return 0;
840                 }
841
842                 af = opt->pf->af;
843         }
844         return af->available(addr, opt);
845 }
846
847 /* Verify that the provided sockaddr looks sendable.   Common verification,
848  * has already been taken care of.
849  */
850 static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
851 {
852         struct sctp_af *af = NULL;
853
854         /* ASSERT: address family has already been verified. */
855         if (addr->sa.sa_family != AF_INET6)
856                 af = sctp_get_af_specific(addr->sa.sa_family);
857         else {
858                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
859                 struct net_device *dev;
860
861                 if (type & IPV6_ADDR_LINKLOCAL) {
862                         if (!addr->v6.sin6_scope_id)
863                                 return 0;
864                         rcu_read_lock();
865                         dev = dev_get_by_index_rcu(&init_net,
866                                                    addr->v6.sin6_scope_id);
867                         rcu_read_unlock();
868                         if (!dev)
869                                 return 0;
870                 }
871                 af = opt->pf->af;
872         }
873
874         return af != NULL;
875 }
876
877 /* Fill in Supported Address Type information for INIT and INIT-ACK
878  * chunks.   Note: In the future, we may want to look at sock options
879  * to determine whether a PF_INET6 socket really wants to have IPV4
880  * addresses.
881  * Returns number of addresses supported.
882  */
883 static int sctp_inet6_supported_addrs(const struct sctp_sock *opt,
884                                       __be16 *types)
885 {
886         types[0] = SCTP_PARAM_IPV6_ADDRESS;
887         if (!opt || !ipv6_only_sock(sctp_opt2sk(opt))) {
888                 types[1] = SCTP_PARAM_IPV4_ADDRESS;
889                 return 2;
890         }
891         return 1;
892 }
893
894 static const struct proto_ops inet6_seqpacket_ops = {
895         .family            = PF_INET6,
896         .owner             = THIS_MODULE,
897         .release           = inet6_release,
898         .bind              = inet6_bind,
899         .connect           = inet_dgram_connect,
900         .socketpair        = sock_no_socketpair,
901         .accept            = inet_accept,
902         .getname           = inet6_getname,
903         .poll              = sctp_poll,
904         .ioctl             = inet6_ioctl,
905         .listen            = sctp_inet_listen,
906         .shutdown          = inet_shutdown,
907         .setsockopt        = sock_common_setsockopt,
908         .getsockopt        = sock_common_getsockopt,
909         .sendmsg           = inet_sendmsg,
910         .recvmsg           = sock_common_recvmsg,
911         .mmap              = sock_no_mmap,
912 #ifdef CONFIG_COMPAT
913         .compat_setsockopt = compat_sock_common_setsockopt,
914         .compat_getsockopt = compat_sock_common_getsockopt,
915 #endif
916 };
917
918 static struct inet_protosw sctpv6_seqpacket_protosw = {
919         .type          = SOCK_SEQPACKET,
920         .protocol      = IPPROTO_SCTP,
921         .prot          = &sctpv6_prot,
922         .ops           = &inet6_seqpacket_ops,
923         .no_check      = 0,
924         .flags         = SCTP_PROTOSW_FLAG
925 };
926 static struct inet_protosw sctpv6_stream_protosw = {
927         .type          = SOCK_STREAM,
928         .protocol      = IPPROTO_SCTP,
929         .prot          = &sctpv6_prot,
930         .ops           = &inet6_seqpacket_ops,
931         .no_check      = 0,
932         .flags         = SCTP_PROTOSW_FLAG,
933 };
934
935 static int sctp6_rcv(struct sk_buff *skb)
936 {
937         return sctp_rcv(skb) ? -1 : 0;
938 }
939
940 static const struct inet6_protocol sctpv6_protocol = {
941         .handler      = sctp6_rcv,
942         .err_handler  = sctp_v6_err,
943         .flags        = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
944 };
945
946 static struct sctp_af sctp_af_inet6 = {
947         .sa_family         = AF_INET6,
948         .sctp_xmit         = sctp_v6_xmit,
949         .setsockopt        = ipv6_setsockopt,
950         .getsockopt        = ipv6_getsockopt,
951         .get_dst           = sctp_v6_get_dst,
952         .get_saddr         = sctp_v6_get_saddr,
953         .copy_addrlist     = sctp_v6_copy_addrlist,
954         .from_skb          = sctp_v6_from_skb,
955         .from_sk           = sctp_v6_from_sk,
956         .to_sk_saddr       = sctp_v6_to_sk_saddr,
957         .to_sk_daddr       = sctp_v6_to_sk_daddr,
958         .from_addr_param   = sctp_v6_from_addr_param,
959         .to_addr_param     = sctp_v6_to_addr_param,
960         .dst_saddr         = sctp_v6_dst_saddr,
961         .cmp_addr          = sctp_v6_cmp_addr,
962         .scope             = sctp_v6_scope,
963         .addr_valid        = sctp_v6_addr_valid,
964         .inaddr_any        = sctp_v6_inaddr_any,
965         .is_any            = sctp_v6_is_any,
966         .available         = sctp_v6_available,
967         .skb_iif           = sctp_v6_skb_iif,
968         .is_ce             = sctp_v6_is_ce,
969         .seq_dump_addr     = sctp_v6_seq_dump_addr,
970         .ecn_capable       = sctp_v6_ecn_capable,
971         .net_header_len    = sizeof(struct ipv6hdr),
972         .sockaddr_len      = sizeof(struct sockaddr_in6),
973 #ifdef CONFIG_COMPAT
974         .compat_setsockopt = compat_ipv6_setsockopt,
975         .compat_getsockopt = compat_ipv6_getsockopt,
976 #endif
977 };
978
979 static struct sctp_pf sctp_pf_inet6 = {
980         .event_msgname = sctp_inet6_event_msgname,
981         .skb_msgname   = sctp_inet6_skb_msgname,
982         .af_supported  = sctp_inet6_af_supported,
983         .cmp_addr      = sctp_inet6_cmp_addr,
984         .bind_verify   = sctp_inet6_bind_verify,
985         .send_verify   = sctp_inet6_send_verify,
986         .supported_addrs = sctp_inet6_supported_addrs,
987         .create_accept_sk = sctp_v6_create_accept_sk,
988         .addr_v4map    = sctp_v6_addr_v4map,
989         .af            = &sctp_af_inet6,
990 };
991
992 /* Initialize IPv6 support and register with socket layer.  */
993 void sctp_v6_pf_init(void)
994 {
995         /* Register the SCTP specific PF_INET6 functions. */
996         sctp_register_pf(&sctp_pf_inet6, PF_INET6);
997
998         /* Register the SCTP specific AF_INET6 functions. */
999         sctp_register_af(&sctp_af_inet6);
1000 }
1001
1002 void sctp_v6_pf_exit(void)
1003 {
1004         list_del(&sctp_af_inet6.list);
1005 }
1006
1007 /* Initialize IPv6 support and register with socket layer.  */
1008 int sctp_v6_protosw_init(void)
1009 {
1010         int rc;
1011
1012         rc = proto_register(&sctpv6_prot, 1);
1013         if (rc)
1014                 return rc;
1015
1016         /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
1017         inet6_register_protosw(&sctpv6_seqpacket_protosw);
1018         inet6_register_protosw(&sctpv6_stream_protosw);
1019
1020         return 0;
1021 }
1022
1023 void sctp_v6_protosw_exit(void)
1024 {
1025         inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
1026         inet6_unregister_protosw(&sctpv6_stream_protosw);
1027         proto_unregister(&sctpv6_prot);
1028 }
1029
1030
1031 /* Register with inet6 layer. */
1032 int sctp_v6_add_protocol(void)
1033 {
1034         /* Register notifier for inet6 address additions/deletions. */
1035         register_inet6addr_notifier(&sctp_inet6addr_notifier);
1036
1037         if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
1038                 return -EAGAIN;
1039
1040         return 0;
1041 }
1042
1043 /* Unregister with inet6 layer. */
1044 void sctp_v6_del_protocol(void)
1045 {
1046         inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
1047         unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
1048 }