sctp: Drop ipfargok in sctp_xmit function
[linux-2.6.git] / net / sctp / ipv6.c
1 /* SCTP kernel implementation
2  * (C) Copyright IBM Corp. 2002, 2004
3  * Copyright (c) 2001 Nokia, Inc.
4  * Copyright (c) 2001 La Monte H.P. Yarroll
5  * Copyright (c) 2002-2003 Intel Corp.
6  *
7  * This file is part of the SCTP kernel implementation
8  *
9  * SCTP over IPv6.
10  *
11  * This SCTP implementation is free software;
12  * you can redistribute it and/or modify it under the terms of
13  * the GNU General Public License as published by
14  * the Free Software Foundation; either version 2, or (at your option)
15  * any later version.
16  *
17  * This SCTP implementation is distributed in the hope that it
18  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
19  *                 ************************
20  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
21  * See the GNU General Public License for more details.
22  *
23  * You should have received a copy of the GNU General Public License
24  * along with GNU CC; see the file COPYING.  If not, write to
25  * the Free Software Foundation, 59 Temple Place - Suite 330,
26  * Boston, MA 02111-1307, USA.
27  *
28  * Please send any bug reports or fixes you make to the
29  * email address(es):
30  *    lksctp developers <lksctp-developers@lists.sourceforge.net>
31  *
32  * Or submit a bug report through the following website:
33  *    http://www.sf.net/projects/lksctp
34  *
35  * Written or modified by:
36  *    Le Yanqun             <yanqun.le@nokia.com>
37  *    Hui Huang             <hui.huang@nokia.com>
38  *    La Monte H.P. Yarroll <piggy@acm.org>
39  *    Sridhar Samudrala     <sri@us.ibm.com>
40  *    Jon Grimm             <jgrimm@us.ibm.com>
41  *    Ardelle Fan           <ardelle.fan@intel.com>
42  *
43  * Based on:
44  *      linux/net/ipv6/tcp_ipv6.c
45  *
46  * Any bugs reported given to us we will try to fix... any fixes shared will
47  * be incorporated into the next SCTP release.
48  */
49
50 #include <linux/module.h>
51 #include <linux/errno.h>
52 #include <linux/types.h>
53 #include <linux/socket.h>
54 #include <linux/sockios.h>
55 #include <linux/net.h>
56 #include <linux/in.h>
57 #include <linux/in6.h>
58 #include <linux/netdevice.h>
59 #include <linux/init.h>
60 #include <linux/ipsec.h>
61
62 #include <linux/ipv6.h>
63 #include <linux/icmpv6.h>
64 #include <linux/random.h>
65 #include <linux/seq_file.h>
66
67 #include <net/protocol.h>
68 #include <net/ndisc.h>
69 #include <net/ip.h>
70 #include <net/ipv6.h>
71 #include <net/transp_v6.h>
72 #include <net/addrconf.h>
73 #include <net/ip6_route.h>
74 #include <net/inet_common.h>
75 #include <net/inet_ecn.h>
76 #include <net/sctp/sctp.h>
77
78 #include <asm/uaccess.h>
79
80 /* Event handler for inet6 address addition/deletion events.
81  * The sctp_local_addr_list needs to be protocted by a spin lock since
82  * multiple notifiers (say IPv4 and IPv6) may be running at the same
83  * time and thus corrupt the list.
84  * The reader side is protected with RCU.
85  */
86 static int sctp_inet6addr_event(struct notifier_block *this, unsigned long ev,
87                                 void *ptr)
88 {
89         struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
90         struct sctp_sockaddr_entry *addr = NULL;
91         struct sctp_sockaddr_entry *temp;
92         int found = 0;
93
94         switch (ev) {
95         case NETDEV_UP:
96                 addr = kmalloc(sizeof(struct sctp_sockaddr_entry), GFP_ATOMIC);
97                 if (addr) {
98                         addr->a.v6.sin6_family = AF_INET6;
99                         addr->a.v6.sin6_port = 0;
100                         memcpy(&addr->a.v6.sin6_addr, &ifa->addr,
101                                  sizeof(struct in6_addr));
102                         addr->a.v6.sin6_scope_id = ifa->idev->dev->ifindex;
103                         addr->valid = 1;
104                         spin_lock_bh(&sctp_local_addr_lock);
105                         list_add_tail_rcu(&addr->list, &sctp_local_addr_list);
106                         spin_unlock_bh(&sctp_local_addr_lock);
107                 }
108                 break;
109         case NETDEV_DOWN:
110                 spin_lock_bh(&sctp_local_addr_lock);
111                 list_for_each_entry_safe(addr, temp,
112                                         &sctp_local_addr_list, list) {
113                         if (addr->a.sa.sa_family == AF_INET6 &&
114                                         ipv6_addr_equal(&addr->a.v6.sin6_addr,
115                                                 &ifa->addr)) {
116                                 found = 1;
117                                 addr->valid = 0;
118                                 list_del_rcu(&addr->list);
119                                 break;
120                         }
121                 }
122                 spin_unlock_bh(&sctp_local_addr_lock);
123                 if (found)
124                         call_rcu(&addr->rcu, sctp_local_addr_free);
125                 break;
126         }
127
128         return NOTIFY_DONE;
129 }
130
131 static struct notifier_block sctp_inet6addr_notifier = {
132         .notifier_call = sctp_inet6addr_event,
133 };
134
135 /* ICMP error handler. */
136 SCTP_STATIC void sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
137                              int type, int code, int offset, __be32 info)
138 {
139         struct inet6_dev *idev;
140         struct sock *sk;
141         struct sctp_association *asoc;
142         struct sctp_transport *transport;
143         struct ipv6_pinfo *np;
144         sk_buff_data_t saveip, savesctp;
145         int err;
146
147         idev = in6_dev_get(skb->dev);
148
149         /* Fix up skb to look at the embedded net header. */
150         saveip   = skb->network_header;
151         savesctp = skb->transport_header;
152         skb_reset_network_header(skb);
153         skb_set_transport_header(skb, offset);
154         sk = sctp_err_lookup(AF_INET6, skb, sctp_hdr(skb), &asoc, &transport);
155         /* Put back, the original pointers. */
156         skb->network_header   = saveip;
157         skb->transport_header = savesctp;
158         if (!sk) {
159                 ICMP6_INC_STATS_BH(idev, ICMP6_MIB_INERRORS);
160                 goto out;
161         }
162
163         /* Warning:  The sock lock is held.  Remember to call
164          * sctp_err_finish!
165          */
166
167         switch (type) {
168         case ICMPV6_PKT_TOOBIG:
169                 sctp_icmp_frag_needed(sk, asoc, transport, ntohl(info));
170                 goto out_unlock;
171         case ICMPV6_PARAMPROB:
172                 if (ICMPV6_UNK_NEXTHDR == code) {
173                         sctp_icmp_proto_unreachable(sk, asoc, transport);
174                         goto out_unlock;
175                 }
176                 break;
177         default:
178                 break;
179         }
180
181         np = inet6_sk(sk);
182         icmpv6_err_convert(type, code, &err);
183         if (!sock_owned_by_user(sk) && np->recverr) {
184                 sk->sk_err = err;
185                 sk->sk_error_report(sk);
186         } else {  /* Only an error on timeout */
187                 sk->sk_err_soft = err;
188         }
189
190 out_unlock:
191         sctp_err_finish(sk, asoc);
192 out:
193         if (likely(idev != NULL))
194                 in6_dev_put(idev);
195 }
196
197 /* Based on tcp_v6_xmit() in tcp_ipv6.c. */
198 static int sctp_v6_xmit(struct sk_buff *skb, struct sctp_transport *transport)
199 {
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, "
227                           "src:" NIP6_FMT " dst:" NIP6_FMT "\n",
228                           __func__, skb, skb->len,
229                           NIP6(fl.fl6_src), NIP6(fl.fl6_dst));
230
231         SCTP_INC_STATS(SCTP_MIB_OUTSCTPPACKS);
232
233         if (!(transport->param_flags & SPP_PMTUD_ENABLE))
234                 skb->local_df = 1;
235
236         return ip6_xmit(sk, skb, &fl, np->opt, 0);
237 }
238
239 /* Returns the dst cache entry for the given source and destination ip
240  * addresses.
241  */
242 static struct dst_entry *sctp_v6_get_dst(struct sctp_association *asoc,
243                                          union sctp_addr *daddr,
244                                          union sctp_addr *saddr)
245 {
246         struct dst_entry *dst;
247         struct flowi fl;
248
249         memset(&fl, 0, sizeof(fl));
250         ipv6_addr_copy(&fl.fl6_dst, &daddr->v6.sin6_addr);
251         if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
252                 fl.oif = daddr->v6.sin6_scope_id;
253
254
255         SCTP_DEBUG_PRINTK("%s: DST=" NIP6_FMT " ",
256                           __func__, NIP6(fl.fl6_dst));
257
258         if (saddr) {
259                 ipv6_addr_copy(&fl.fl6_src, &saddr->v6.sin6_addr);
260                 SCTP_DEBUG_PRINTK(
261                         "SRC=" NIP6_FMT " - ",
262                         NIP6(fl.fl6_src));
263         }
264
265         dst = ip6_route_output(&init_net, NULL, &fl);
266         if (!dst->error) {
267                 struct rt6_info *rt;
268                 rt = (struct rt6_info *)dst;
269                 SCTP_DEBUG_PRINTK(
270                         "rt6_dst:" NIP6_FMT " rt6_src:" NIP6_FMT "\n",
271                         NIP6(rt->rt6i_dst.addr), NIP6(rt->rt6i_src.addr));
272                 return dst;
273         }
274         SCTP_DEBUG_PRINTK("NO ROUTE\n");
275         dst_release(dst);
276         return NULL;
277 }
278
279 /* Returns the number of consecutive initial bits that match in the 2 ipv6
280  * addresses.
281  */
282 static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
283                                          union sctp_addr *s2)
284 {
285         struct in6_addr *a1 = &s1->v6.sin6_addr;
286         struct in6_addr *a2 = &s2->v6.sin6_addr;
287         int i, j;
288
289         for (i = 0; i < 4 ; i++) {
290                 __be32 a1xora2;
291
292                 a1xora2 = a1->s6_addr32[i] ^ a2->s6_addr32[i];
293
294                 if ((j = fls(ntohl(a1xora2))))
295                         return (i * 32 + 32 - j);
296         }
297
298         return (i*32);
299 }
300
301 /* Fills in the source address(saddr) based on the destination address(daddr)
302  * and asoc's bind address list.
303  */
304 static void sctp_v6_get_saddr(struct sctp_sock *sk,
305                               struct sctp_association *asoc,
306                               struct dst_entry *dst,
307                               union sctp_addr *daddr,
308                               union sctp_addr *saddr)
309 {
310         struct sctp_bind_addr *bp;
311         struct sctp_sockaddr_entry *laddr;
312         sctp_scope_t scope;
313         union sctp_addr *baddr = NULL;
314         __u8 matchlen = 0;
315         __u8 bmatchlen;
316
317         SCTP_DEBUG_PRINTK("%s: asoc:%p dst:%p "
318                           "daddr:" NIP6_FMT " ",
319                           __func__, asoc, dst, NIP6(daddr->v6.sin6_addr));
320
321         if (!asoc) {
322                 ipv6_dev_get_saddr(dst ? ip6_dst_idev(dst)->dev : NULL,
323                                    &daddr->v6.sin6_addr,
324                                    inet6_sk(&sk->inet.sk)->srcprefs,
325                                    &saddr->v6.sin6_addr);
326                 SCTP_DEBUG_PRINTK("saddr from ipv6_get_saddr: " NIP6_FMT "\n",
327                                   NIP6(saddr->v6.sin6_addr));
328                 return;
329         }
330
331         scope = sctp_scope(daddr);
332
333         bp = &asoc->base.bind_addr;
334
335         /* Go through the bind address list and find the best source address
336          * that matches the scope of the destination address.
337          */
338         rcu_read_lock();
339         list_for_each_entry_rcu(laddr, &bp->address_list, list) {
340                 if (!laddr->valid)
341                         continue;
342                 if ((laddr->state == SCTP_ADDR_SRC) &&
343                     (laddr->a.sa.sa_family == AF_INET6) &&
344                     (scope <= sctp_scope(&laddr->a))) {
345                         bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a);
346                         if (!baddr || (matchlen < bmatchlen)) {
347                                 baddr = &laddr->a;
348                                 matchlen = bmatchlen;
349                         }
350                 }
351         }
352
353         if (baddr) {
354                 memcpy(saddr, baddr, sizeof(union sctp_addr));
355                 SCTP_DEBUG_PRINTK("saddr: " NIP6_FMT "\n",
356                                   NIP6(saddr->v6.sin6_addr));
357         } else {
358                 printk(KERN_ERR "%s: asoc:%p Could not find a valid source "
359                        "address for the dest:" NIP6_FMT "\n",
360                        __func__, asoc, NIP6(daddr->v6.sin6_addr));
361         }
362
363         rcu_read_unlock();
364 }
365
366 /* Make a copy of all potential local addresses. */
367 static void sctp_v6_copy_addrlist(struct list_head *addrlist,
368                                   struct net_device *dev)
369 {
370         struct inet6_dev *in6_dev;
371         struct inet6_ifaddr *ifp;
372         struct sctp_sockaddr_entry *addr;
373
374         rcu_read_lock();
375         if ((in6_dev = __in6_dev_get(dev)) == NULL) {
376                 rcu_read_unlock();
377                 return;
378         }
379
380         read_lock_bh(&in6_dev->lock);
381         for (ifp = in6_dev->addr_list; ifp; ifp = ifp->if_next) {
382                 /* Add the address to the local list.  */
383                 addr = t_new(struct sctp_sockaddr_entry, GFP_ATOMIC);
384                 if (addr) {
385                         addr->a.v6.sin6_family = AF_INET6;
386                         addr->a.v6.sin6_port = 0;
387                         addr->a.v6.sin6_addr = ifp->addr;
388                         addr->a.v6.sin6_scope_id = dev->ifindex;
389                         addr->valid = 1;
390                         INIT_LIST_HEAD(&addr->list);
391                         INIT_RCU_HEAD(&addr->rcu);
392                         list_add_tail(&addr->list, addrlist);
393                 }
394         }
395
396         read_unlock_bh(&in6_dev->lock);
397         rcu_read_unlock();
398 }
399
400 /* Initialize a sockaddr_storage from in incoming skb. */
401 static void sctp_v6_from_skb(union sctp_addr *addr,struct sk_buff *skb,
402                              int is_saddr)
403 {
404         void *from;
405         __be16 *port;
406         struct sctphdr *sh;
407
408         port = &addr->v6.sin6_port;
409         addr->v6.sin6_family = AF_INET6;
410         addr->v6.sin6_flowinfo = 0; /* FIXME */
411         addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif;
412
413         sh = sctp_hdr(skb);
414         if (is_saddr) {
415                 *port  = sh->source;
416                 from = &ipv6_hdr(skb)->saddr;
417         } else {
418                 *port = sh->dest;
419                 from = &ipv6_hdr(skb)->daddr;
420         }
421         ipv6_addr_copy(&addr->v6.sin6_addr, from);
422 }
423
424 /* Initialize an sctp_addr from a socket. */
425 static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk)
426 {
427         addr->v6.sin6_family = AF_INET6;
428         addr->v6.sin6_port = 0;
429         addr->v6.sin6_addr = inet6_sk(sk)->rcv_saddr;
430 }
431
432 /* Initialize sk->sk_rcv_saddr from sctp_addr. */
433 static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
434 {
435         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
436                 inet6_sk(sk)->rcv_saddr.s6_addr32[0] = 0;
437                 inet6_sk(sk)->rcv_saddr.s6_addr32[1] = 0;
438                 inet6_sk(sk)->rcv_saddr.s6_addr32[2] = htonl(0x0000ffff);
439                 inet6_sk(sk)->rcv_saddr.s6_addr32[3] =
440                         addr->v4.sin_addr.s_addr;
441         } else {
442                 inet6_sk(sk)->rcv_saddr = addr->v6.sin6_addr;
443         }
444 }
445
446 /* Initialize sk->sk_daddr from sctp_addr. */
447 static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
448 {
449         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
450                 inet6_sk(sk)->daddr.s6_addr32[0] = 0;
451                 inet6_sk(sk)->daddr.s6_addr32[1] = 0;
452                 inet6_sk(sk)->daddr.s6_addr32[2] = htonl(0x0000ffff);
453                 inet6_sk(sk)->daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
454         } else {
455                 inet6_sk(sk)->daddr = addr->v6.sin6_addr;
456         }
457 }
458
459 /* Initialize a sctp_addr from an address parameter. */
460 static void sctp_v6_from_addr_param(union sctp_addr *addr,
461                                     union sctp_addr_param *param,
462                                     __be16 port, int iif)
463 {
464         addr->v6.sin6_family = AF_INET6;
465         addr->v6.sin6_port = port;
466         addr->v6.sin6_flowinfo = 0; /* BUG */
467         ipv6_addr_copy(&addr->v6.sin6_addr, &param->v6.addr);
468         addr->v6.sin6_scope_id = iif;
469 }
470
471 /* Initialize an address parameter from a sctp_addr and return the length
472  * of the address parameter.
473  */
474 static int sctp_v6_to_addr_param(const union sctp_addr *addr,
475                                  union sctp_addr_param *param)
476 {
477         int length = sizeof(sctp_ipv6addr_param_t);
478
479         param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS;
480         param->v6.param_hdr.length = htons(length);
481         ipv6_addr_copy(&param->v6.addr, &addr->v6.sin6_addr);
482
483         return length;
484 }
485
486 /* Initialize a sctp_addr from a dst_entry. */
487 static void sctp_v6_dst_saddr(union sctp_addr *addr, struct dst_entry *dst,
488                               __be16 port)
489 {
490         struct rt6_info *rt = (struct rt6_info *)dst;
491         addr->sa.sa_family = AF_INET6;
492         addr->v6.sin6_port = port;
493         ipv6_addr_copy(&addr->v6.sin6_addr, &rt->rt6i_src.addr);
494 }
495
496 /* Compare addresses exactly.
497  * v4-mapped-v6 is also in consideration.
498  */
499 static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
500                             const union sctp_addr *addr2)
501 {
502         if (addr1->sa.sa_family != addr2->sa.sa_family) {
503                 if (addr1->sa.sa_family == AF_INET &&
504                     addr2->sa.sa_family == AF_INET6 &&
505                     ipv6_addr_v4mapped(&addr2->v6.sin6_addr)) {
506                         if (addr2->v6.sin6_port == addr1->v4.sin_port &&
507                             addr2->v6.sin6_addr.s6_addr32[3] ==
508                             addr1->v4.sin_addr.s_addr)
509                                 return 1;
510                 }
511                 if (addr2->sa.sa_family == AF_INET &&
512                     addr1->sa.sa_family == AF_INET6 &&
513                     ipv6_addr_v4mapped(&addr1->v6.sin6_addr)) {
514                         if (addr1->v6.sin6_port == addr2->v4.sin_port &&
515                             addr1->v6.sin6_addr.s6_addr32[3] ==
516                             addr2->v4.sin_addr.s_addr)
517                                 return 1;
518                 }
519                 return 0;
520         }
521         if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))
522                 return 0;
523         /* If this is a linklocal address, compare the scope_id. */
524         if (ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) {
525                 if (addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&
526                     (addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)) {
527                         return 0;
528                 }
529         }
530
531         return 1;
532 }
533
534 /* Initialize addr struct to INADDR_ANY. */
535 static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port)
536 {
537         memset(addr, 0x00, sizeof(union sctp_addr));
538         addr->v6.sin6_family = AF_INET6;
539         addr->v6.sin6_port = port;
540 }
541
542 /* Is this a wildcard address? */
543 static int sctp_v6_is_any(const union sctp_addr *addr)
544 {
545         return ipv6_addr_any(&addr->v6.sin6_addr);
546 }
547
548 /* Should this be available for binding?   */
549 static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp)
550 {
551         int type;
552         struct in6_addr *in6 = (struct in6_addr *)&addr->v6.sin6_addr;
553
554         type = ipv6_addr_type(in6);
555         if (IPV6_ADDR_ANY == type)
556                 return 1;
557         if (type == IPV6_ADDR_MAPPED) {
558                 if (sp && !sp->v4mapped)
559                         return 0;
560                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
561                         return 0;
562                 sctp_v6_map_v4(addr);
563                 return sctp_get_af_specific(AF_INET)->available(addr, sp);
564         }
565         if (!(type & IPV6_ADDR_UNICAST))
566                 return 0;
567
568         return ipv6_chk_addr(&init_net, in6, NULL, 0);
569 }
570
571 /* This function checks if the address is a valid address to be used for
572  * SCTP.
573  *
574  * Output:
575  * Return 0 - If the address is a non-unicast or an illegal address.
576  * Return 1 - If the address is a unicast.
577  */
578 static int sctp_v6_addr_valid(union sctp_addr *addr,
579                               struct sctp_sock *sp,
580                               const struct sk_buff *skb)
581 {
582         int ret = ipv6_addr_type(&addr->v6.sin6_addr);
583
584         /* Support v4-mapped-v6 address. */
585         if (ret == IPV6_ADDR_MAPPED) {
586                 /* Note: This routine is used in input, so v4-mapped-v6
587                  * are disallowed here when there is no sctp_sock.
588                  */
589                 if (!sp || !sp->v4mapped)
590                         return 0;
591                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
592                         return 0;
593                 sctp_v6_map_v4(addr);
594                 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb);
595         }
596
597         /* Is this a non-unicast address */
598         if (!(ret & IPV6_ADDR_UNICAST))
599                 return 0;
600
601         return 1;
602 }
603
604 /* What is the scope of 'addr'?  */
605 static sctp_scope_t sctp_v6_scope(union sctp_addr *addr)
606 {
607         int v6scope;
608         sctp_scope_t retval;
609
610         /* The IPv6 scope is really a set of bit fields.
611          * See IFA_* in <net/if_inet6.h>.  Map to a generic SCTP scope.
612          */
613
614         v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
615         switch (v6scope) {
616         case IFA_HOST:
617                 retval = SCTP_SCOPE_LOOPBACK;
618                 break;
619         case IFA_LINK:
620                 retval = SCTP_SCOPE_LINK;
621                 break;
622         case IFA_SITE:
623                 retval = SCTP_SCOPE_PRIVATE;
624                 break;
625         default:
626                 retval = SCTP_SCOPE_GLOBAL;
627                 break;
628         }
629
630         return retval;
631 }
632
633 /* Create and initialize a new sk for the socket to be returned by accept(). */
634 static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
635                                              struct sctp_association *asoc)
636 {
637         struct inet_sock *inet = inet_sk(sk);
638         struct sock *newsk;
639         struct inet_sock *newinet;
640         struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
641         struct sctp6_sock *newsctp6sk;
642
643         newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot);
644         if (!newsk)
645                 goto out;
646
647         sock_init_data(NULL, newsk);
648
649         newsk->sk_type = SOCK_STREAM;
650
651         newsk->sk_prot = sk->sk_prot;
652         newsk->sk_no_check = sk->sk_no_check;
653         newsk->sk_reuse = sk->sk_reuse;
654
655         newsk->sk_destruct = inet_sock_destruct;
656         newsk->sk_family = PF_INET6;
657         newsk->sk_protocol = IPPROTO_SCTP;
658         newsk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
659         newsk->sk_shutdown = sk->sk_shutdown;
660         sock_reset_flag(sk, SOCK_ZAPPED);
661
662         newsctp6sk = (struct sctp6_sock *)newsk;
663         inet_sk(newsk)->pinet6 = &newsctp6sk->inet6;
664
665         sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped;
666
667         newinet = inet_sk(newsk);
668         newnp = inet6_sk(newsk);
669
670         memcpy(newnp, np, sizeof(struct ipv6_pinfo));
671
672         /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
673          * and getpeername().
674          */
675         newinet->sport = inet->sport;
676         newnp->saddr = np->saddr;
677         newnp->rcv_saddr = np->rcv_saddr;
678         newinet->dport = htons(asoc->peer.port);
679         sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
680
681         /* Init the ipv4 part of the socket since we can have sockets
682          * using v6 API for ipv4.
683          */
684         newinet->uc_ttl = -1;
685         newinet->mc_loop = 1;
686         newinet->mc_ttl = 1;
687         newinet->mc_index = 0;
688         newinet->mc_list = NULL;
689
690         if (ipv4_config.no_pmtu_disc)
691                 newinet->pmtudisc = IP_PMTUDISC_DONT;
692         else
693                 newinet->pmtudisc = IP_PMTUDISC_WANT;
694
695         sk_refcnt_debug_inc(newsk);
696
697         if (newsk->sk_prot->init(newsk)) {
698                 sk_common_release(newsk);
699                 newsk = NULL;
700         }
701
702 out:
703         return newsk;
704 }
705
706 /* Map v4 address to mapped v6 address */
707 static void sctp_v6_addr_v4map(struct sctp_sock *sp, union sctp_addr *addr)
708 {
709         if (sp->v4mapped && AF_INET == addr->sa.sa_family)
710                 sctp_v4_map_v6(addr);
711 }
712
713 /* Where did this skb come from?  */
714 static int sctp_v6_skb_iif(const struct sk_buff *skb)
715 {
716         struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb;
717         return opt->iif;
718 }
719
720 /* Was this packet marked by Explicit Congestion Notification? */
721 static int sctp_v6_is_ce(const struct sk_buff *skb)
722 {
723         return *((__u32 *)(ipv6_hdr(skb))) & htonl(1 << 20);
724 }
725
726 /* Dump the v6 addr to the seq file. */
727 static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
728 {
729         seq_printf(seq, NIP6_FMT " ", NIP6(addr->v6.sin6_addr));
730 }
731
732 static void sctp_v6_ecn_capable(struct sock *sk)
733 {
734         inet6_sk(sk)->tclass |= INET_ECN_ECT_0;
735 }
736
737 /* Initialize a PF_INET6 socket msg_name. */
738 static void sctp_inet6_msgname(char *msgname, int *addr_len)
739 {
740         struct sockaddr_in6 *sin6;
741
742         sin6 = (struct sockaddr_in6 *)msgname;
743         sin6->sin6_family = AF_INET6;
744         sin6->sin6_flowinfo = 0;
745         sin6->sin6_scope_id = 0; /*FIXME */
746         *addr_len = sizeof(struct sockaddr_in6);
747 }
748
749 /* Initialize a PF_INET msgname from a ulpevent. */
750 static void sctp_inet6_event_msgname(struct sctp_ulpevent *event,
751                                      char *msgname, int *addrlen)
752 {
753         struct sockaddr_in6 *sin6, *sin6from;
754
755         if (msgname) {
756                 union sctp_addr *addr;
757                 struct sctp_association *asoc;
758
759                 asoc = event->asoc;
760                 sctp_inet6_msgname(msgname, addrlen);
761                 sin6 = (struct sockaddr_in6 *)msgname;
762                 sin6->sin6_port = htons(asoc->peer.port);
763                 addr = &asoc->peer.primary_addr;
764
765                 /* Note: If we go to a common v6 format, this code
766                  * will change.
767                  */
768
769                 /* Map ipv4 address into v4-mapped-on-v6 address.  */
770                 if (sctp_sk(asoc->base.sk)->v4mapped &&
771                     AF_INET == addr->sa.sa_family) {
772                         sctp_v4_map_v6((union sctp_addr *)sin6);
773                         sin6->sin6_addr.s6_addr32[3] =
774                                 addr->v4.sin_addr.s_addr;
775                         return;
776                 }
777
778                 sin6from = &asoc->peer.primary_addr.v6;
779                 ipv6_addr_copy(&sin6->sin6_addr, &sin6from->sin6_addr);
780                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
781                         sin6->sin6_scope_id = sin6from->sin6_scope_id;
782         }
783 }
784
785 /* Initialize a msg_name from an inbound skb. */
786 static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname,
787                                    int *addr_len)
788 {
789         struct sctphdr *sh;
790         struct sockaddr_in6 *sin6;
791
792         if (msgname) {
793                 sctp_inet6_msgname(msgname, addr_len);
794                 sin6 = (struct sockaddr_in6 *)msgname;
795                 sh = sctp_hdr(skb);
796                 sin6->sin6_port = sh->source;
797
798                 /* Map ipv4 address into v4-mapped-on-v6 address. */
799                 if (sctp_sk(skb->sk)->v4mapped &&
800                     ip_hdr(skb)->version == 4) {
801                         sctp_v4_map_v6((union sctp_addr *)sin6);
802                         sin6->sin6_addr.s6_addr32[3] = ip_hdr(skb)->saddr;
803                         return;
804                 }
805
806                 /* Otherwise, just copy the v6 address. */
807                 ipv6_addr_copy(&sin6->sin6_addr, &ipv6_hdr(skb)->saddr);
808                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) {
809                         struct sctp_ulpevent *ev = sctp_skb2event(skb);
810                         sin6->sin6_scope_id = ev->iif;
811                 }
812         }
813 }
814
815 /* Do we support this AF? */
816 static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp)
817 {
818         switch (family) {
819         case AF_INET6:
820                 return 1;
821         /* v4-mapped-v6 addresses */
822         case AF_INET:
823                 if (!__ipv6_only_sock(sctp_opt2sk(sp)))
824                         return 1;
825         default:
826                 return 0;
827         }
828 }
829
830 /* Address matching with wildcards allowed.  This extra level
831  * of indirection lets us choose whether a PF_INET6 should
832  * disallow any v4 addresses if we so choose.
833  */
834 static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
835                                const union sctp_addr *addr2,
836                                struct sctp_sock *opt)
837 {
838         struct sctp_af *af1, *af2;
839
840         af1 = sctp_get_af_specific(addr1->sa.sa_family);
841         af2 = sctp_get_af_specific(addr2->sa.sa_family);
842
843         if (!af1 || !af2)
844                 return 0;
845
846         /* If the socket is IPv6 only, v4 addrs will not match */
847         if (__ipv6_only_sock(sctp_opt2sk(opt)) && af1 != af2)
848                 return 0;
849
850         /* Today, wildcard AF_INET/AF_INET6. */
851         if (sctp_is_any(addr1) || sctp_is_any(addr2))
852                 return 1;
853
854         if (addr1->sa.sa_family != addr2->sa.sa_family)
855                 return 0;
856
857         return af1->cmp_addr(addr1, addr2);
858 }
859
860 /* Verify that the provided sockaddr looks bindable.   Common verification,
861  * has already been taken care of.
862  */
863 static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
864 {
865         struct sctp_af *af;
866
867         /* ASSERT: address family has already been verified. */
868         if (addr->sa.sa_family != AF_INET6)
869                 af = sctp_get_af_specific(addr->sa.sa_family);
870         else {
871                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
872                 struct net_device *dev;
873
874                 if (type & IPV6_ADDR_LINKLOCAL) {
875                         if (!addr->v6.sin6_scope_id)
876                                 return 0;
877                         dev = dev_get_by_index(&init_net, addr->v6.sin6_scope_id);
878                         if (!dev)
879                                 return 0;
880                         if (!ipv6_chk_addr(&init_net, &addr->v6.sin6_addr,
881                                            dev, 0)) {
882                                 dev_put(dev);
883                                 return 0;
884                         }
885                         dev_put(dev);
886                 } else if (type == IPV6_ADDR_MAPPED) {
887                         if (!opt->v4mapped)
888                                 return 0;
889                 }
890
891                 af = opt->pf->af;
892         }
893         return af->available(addr, opt);
894 }
895
896 /* Verify that the provided sockaddr looks sendable.   Common verification,
897  * has already been taken care of.
898  */
899 static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
900 {
901         struct sctp_af *af = NULL;
902
903         /* ASSERT: address family has already been verified. */
904         if (addr->sa.sa_family != AF_INET6)
905                 af = sctp_get_af_specific(addr->sa.sa_family);
906         else {
907                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
908                 struct net_device *dev;
909
910                 if (type & IPV6_ADDR_LINKLOCAL) {
911                         if (!addr->v6.sin6_scope_id)
912                                 return 0;
913                         dev = dev_get_by_index(&init_net, addr->v6.sin6_scope_id);
914                         if (!dev)
915                                 return 0;
916                         dev_put(dev);
917                 }
918                 af = opt->pf->af;
919         }
920
921         return af != NULL;
922 }
923
924 /* Fill in Supported Address Type information for INIT and INIT-ACK
925  * chunks.   Note: In the future, we may want to look at sock options
926  * to determine whether a PF_INET6 socket really wants to have IPV4
927  * addresses.
928  * Returns number of addresses supported.
929  */
930 static int sctp_inet6_supported_addrs(const struct sctp_sock *opt,
931                                       __be16 *types)
932 {
933         types[0] = SCTP_PARAM_IPV6_ADDRESS;
934         if (!opt || !ipv6_only_sock(sctp_opt2sk(opt))) {
935                 types[1] = SCTP_PARAM_IPV4_ADDRESS;
936                 return 2;
937         }
938         return 1;
939 }
940
941 static const struct proto_ops inet6_seqpacket_ops = {
942         .family            = PF_INET6,
943         .owner             = THIS_MODULE,
944         .release           = inet6_release,
945         .bind              = inet6_bind,
946         .connect           = inet_dgram_connect,
947         .socketpair        = sock_no_socketpair,
948         .accept            = inet_accept,
949         .getname           = inet6_getname,
950         .poll              = sctp_poll,
951         .ioctl             = inet6_ioctl,
952         .listen            = sctp_inet_listen,
953         .shutdown          = inet_shutdown,
954         .setsockopt        = sock_common_setsockopt,
955         .getsockopt        = sock_common_getsockopt,
956         .sendmsg           = inet_sendmsg,
957         .recvmsg           = sock_common_recvmsg,
958         .mmap              = sock_no_mmap,
959 #ifdef CONFIG_COMPAT
960         .compat_setsockopt = compat_sock_common_setsockopt,
961         .compat_getsockopt = compat_sock_common_getsockopt,
962 #endif
963 };
964
965 static struct inet_protosw sctpv6_seqpacket_protosw = {
966         .type          = SOCK_SEQPACKET,
967         .protocol      = IPPROTO_SCTP,
968         .prot          = &sctpv6_prot,
969         .ops           = &inet6_seqpacket_ops,
970         .capability    = -1,
971         .no_check      = 0,
972         .flags         = SCTP_PROTOSW_FLAG
973 };
974 static struct inet_protosw sctpv6_stream_protosw = {
975         .type          = SOCK_STREAM,
976         .protocol      = IPPROTO_SCTP,
977         .prot          = &sctpv6_prot,
978         .ops           = &inet6_seqpacket_ops,
979         .capability    = -1,
980         .no_check      = 0,
981         .flags         = SCTP_PROTOSW_FLAG,
982 };
983
984 static int sctp6_rcv(struct sk_buff *skb)
985 {
986         return sctp_rcv(skb) ? -1 : 0;
987 }
988
989 static struct inet6_protocol sctpv6_protocol = {
990         .handler      = sctp6_rcv,
991         .err_handler  = sctp_v6_err,
992         .flags        = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
993 };
994
995 static struct sctp_af sctp_af_inet6 = {
996         .sa_family         = AF_INET6,
997         .sctp_xmit         = sctp_v6_xmit,
998         .setsockopt        = ipv6_setsockopt,
999         .getsockopt        = ipv6_getsockopt,
1000         .get_dst           = sctp_v6_get_dst,
1001         .get_saddr         = sctp_v6_get_saddr,
1002         .copy_addrlist     = sctp_v6_copy_addrlist,
1003         .from_skb          = sctp_v6_from_skb,
1004         .from_sk           = sctp_v6_from_sk,
1005         .to_sk_saddr       = sctp_v6_to_sk_saddr,
1006         .to_sk_daddr       = sctp_v6_to_sk_daddr,
1007         .from_addr_param   = sctp_v6_from_addr_param,
1008         .to_addr_param     = sctp_v6_to_addr_param,
1009         .dst_saddr         = sctp_v6_dst_saddr,
1010         .cmp_addr          = sctp_v6_cmp_addr,
1011         .scope             = sctp_v6_scope,
1012         .addr_valid        = sctp_v6_addr_valid,
1013         .inaddr_any        = sctp_v6_inaddr_any,
1014         .is_any            = sctp_v6_is_any,
1015         .available         = sctp_v6_available,
1016         .skb_iif           = sctp_v6_skb_iif,
1017         .is_ce             = sctp_v6_is_ce,
1018         .seq_dump_addr     = sctp_v6_seq_dump_addr,
1019         .ecn_capable       = sctp_v6_ecn_capable,
1020         .net_header_len    = sizeof(struct ipv6hdr),
1021         .sockaddr_len      = sizeof(struct sockaddr_in6),
1022 #ifdef CONFIG_COMPAT
1023         .compat_setsockopt = compat_ipv6_setsockopt,
1024         .compat_getsockopt = compat_ipv6_getsockopt,
1025 #endif
1026 };
1027
1028 static struct sctp_pf sctp_pf_inet6 = {
1029         .event_msgname = sctp_inet6_event_msgname,
1030         .skb_msgname   = sctp_inet6_skb_msgname,
1031         .af_supported  = sctp_inet6_af_supported,
1032         .cmp_addr      = sctp_inet6_cmp_addr,
1033         .bind_verify   = sctp_inet6_bind_verify,
1034         .send_verify   = sctp_inet6_send_verify,
1035         .supported_addrs = sctp_inet6_supported_addrs,
1036         .create_accept_sk = sctp_v6_create_accept_sk,
1037         .addr_v4map    = sctp_v6_addr_v4map,
1038         .af            = &sctp_af_inet6,
1039 };
1040
1041 /* Initialize IPv6 support and register with socket layer.  */
1042 void sctp_v6_pf_init(void)
1043 {
1044         /* Register the SCTP specific PF_INET6 functions. */
1045         sctp_register_pf(&sctp_pf_inet6, PF_INET6);
1046
1047         /* Register the SCTP specific AF_INET6 functions. */
1048         sctp_register_af(&sctp_af_inet6);
1049 }
1050
1051 void sctp_v6_pf_exit(void)
1052 {
1053         list_del(&sctp_af_inet6.list);
1054 }
1055
1056 /* Initialize IPv6 support and register with socket layer.  */
1057 int sctp_v6_protosw_init(void)
1058 {
1059         int rc;
1060
1061         rc = proto_register(&sctpv6_prot, 1);
1062         if (rc)
1063                 return rc;
1064
1065         /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
1066         inet6_register_protosw(&sctpv6_seqpacket_protosw);
1067         inet6_register_protosw(&sctpv6_stream_protosw);
1068
1069         return 0;
1070 }
1071
1072 void sctp_v6_protosw_exit(void)
1073 {
1074         inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
1075         inet6_unregister_protosw(&sctpv6_stream_protosw);
1076         proto_unregister(&sctpv6_prot);
1077 }
1078
1079
1080 /* Register with inet6 layer. */
1081 int sctp_v6_add_protocol(void)
1082 {
1083         /* Register notifier for inet6 address additions/deletions. */
1084         register_inet6addr_notifier(&sctp_inet6addr_notifier);
1085
1086         if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
1087                 return -EAGAIN;
1088
1089         return 0;
1090 }
1091
1092 /* Unregister with inet6 layer. */
1093 void sctp_v6_del_protocol(void)
1094 {
1095         inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
1096         unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
1097 }