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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, see
25 * <http://www.gnu.org/licenses/>.
26 *
27 * Please send any bug reports or fixes you make to the
28 * email address(es):
29 * lksctp developers <linux-sctp@vger.kernel.org>
30 *
31 * Written or modified by:
32 * Le Yanqun <yanqun.le@nokia.com>
33 * Hui Huang <hui.huang@nokia.com>
34 * La Monte H.P. Yarroll <piggy@acm.org>
35 * Sridhar Samudrala <sri@us.ibm.com>
36 * Jon Grimm <jgrimm@us.ibm.com>
37 * Ardelle Fan <ardelle.fan@intel.com>
38 *
39 * Based on:
40 * linux/net/ipv6/tcp_ipv6.c
41 */
42
43#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
44
45#include <linux/module.h>
46#include <linux/errno.h>
47#include <linux/types.h>
48#include <linux/socket.h>
49#include <linux/sockios.h>
50#include <linux/net.h>
51#include <linux/in.h>
52#include <linux/in6.h>
53#include <linux/netdevice.h>
54#include <linux/init.h>
55#include <linux/ipsec.h>
56#include <linux/slab.h>
57
58#include <linux/ipv6.h>
59#include <linux/icmpv6.h>
60#include <linux/random.h>
61#include <linux/seq_file.h>
62
63#include <net/protocol.h>
64#include <net/ndisc.h>
65#include <net/ip.h>
66#include <net/ipv6.h>
67#include <net/transp_v6.h>
68#include <net/addrconf.h>
69#include <net/ip6_route.h>
70#include <net/inet_common.h>
71#include <net/inet_ecn.h>
72#include <net/sctp/sctp.h>
73
74#include <linux/uaccess.h>
75
76static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
77 union sctp_addr *s2);
78static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr,
79 __be16 port);
80static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
81 const union sctp_addr *addr2);
82
83/* Event handler for inet6 address addition/deletion events.
84 * The sctp_local_addr_list needs to be protocted by a spin lock since
85 * multiple notifiers (say IPv4 and IPv6) may be running at the same
86 * time and thus corrupt the list.
87 * The reader side is protected with RCU.
88 */
89static int sctp_inet6addr_event(struct notifier_block *this, unsigned long ev,
90 void *ptr)
91{
92 struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
93 struct sctp_sockaddr_entry *addr = NULL;
94 struct sctp_sockaddr_entry *temp;
95 struct net *net = dev_net(ifa->idev->dev);
96 int found = 0;
97
98 switch (ev) {
99 case NETDEV_UP:
100 addr = kmalloc(sizeof(struct sctp_sockaddr_entry), GFP_ATOMIC);
101 if (addr) {
102 addr->a.v6.sin6_family = AF_INET6;
103 addr->a.v6.sin6_port = 0;
104 addr->a.v6.sin6_addr = ifa->addr;
105 addr->a.v6.sin6_scope_id = ifa->idev->dev->ifindex;
106 addr->valid = 1;
107 spin_lock_bh(&net->sctp.local_addr_lock);
108 list_add_tail_rcu(&addr->list, &net->sctp.local_addr_list);
109 sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_NEW);
110 spin_unlock_bh(&net->sctp.local_addr_lock);
111 }
112 break;
113 case NETDEV_DOWN:
114 spin_lock_bh(&net->sctp.local_addr_lock);
115 list_for_each_entry_safe(addr, temp,
116 &net->sctp.local_addr_list, list) {
117 if (addr->a.sa.sa_family == AF_INET6 &&
118 ipv6_addr_equal(&addr->a.v6.sin6_addr,
119 &ifa->addr)) {
120 sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_DEL);
121 found = 1;
122 addr->valid = 0;
123 list_del_rcu(&addr->list);
124 break;
125 }
126 }
127 spin_unlock_bh(&net->sctp.local_addr_lock);
128 if (found)
129 kfree_rcu(addr, rcu);
130 break;
131 }
132
133 return NOTIFY_DONE;
134}
135
136static struct notifier_block sctp_inet6addr_notifier = {
137 .notifier_call = sctp_inet6addr_event,
138};
139
140/* ICMP error handler. */
141static void sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
142 u8 type, u8 code, int offset, __be32 info)
143{
144 struct inet6_dev *idev;
145 struct sock *sk;
146 struct sctp_association *asoc;
147 struct sctp_transport *transport;
148 struct ipv6_pinfo *np;
149 __u16 saveip, savesctp;
150 int err;
151 struct net *net = dev_net(skb->dev);
152
153 idev = in6_dev_get(skb->dev);
154
155 /* Fix up skb to look at the embedded net header. */
156 saveip = skb->network_header;
157 savesctp = skb->transport_header;
158 skb_reset_network_header(skb);
159 skb_set_transport_header(skb, offset);
160 sk = sctp_err_lookup(net, AF_INET6, skb, sctp_hdr(skb), &asoc, &transport);
161 /* Put back, the original pointers. */
162 skb->network_header = saveip;
163 skb->transport_header = savesctp;
164 if (!sk) {
165 __ICMP6_INC_STATS(net, idev, ICMP6_MIB_INERRORS);
166 goto out;
167 }
168
169 /* Warning: The sock lock is held. Remember to call
170 * sctp_err_finish!
171 */
172
173 switch (type) {
174 case ICMPV6_PKT_TOOBIG:
175 if (ip6_sk_accept_pmtu(sk))
176 sctp_icmp_frag_needed(sk, asoc, transport, ntohl(info));
177 goto out_unlock;
178 case ICMPV6_PARAMPROB:
179 if (ICMPV6_UNK_NEXTHDR == code) {
180 sctp_icmp_proto_unreachable(sk, asoc, transport);
181 goto out_unlock;
182 }
183 break;
184 case NDISC_REDIRECT:
185 sctp_icmp_redirect(sk, transport, skb);
186 goto out_unlock;
187 default:
188 break;
189 }
190
191 np = inet6_sk(sk);
192 icmpv6_err_convert(type, code, &err);
193 if (!sock_owned_by_user(sk) && np->recverr) {
194 sk->sk_err = err;
195 sk->sk_error_report(sk);
196 } else { /* Only an error on timeout */
197 sk->sk_err_soft = err;
198 }
199
200out_unlock:
201 sctp_err_finish(sk, transport);
202out:
203 if (likely(idev != NULL))
204 in6_dev_put(idev);
205}
206
207static int sctp_v6_xmit(struct sk_buff *skb, struct sctp_transport *transport)
208{
209 struct sock *sk = skb->sk;
210 struct ipv6_pinfo *np = inet6_sk(sk);
211 struct flowi6 *fl6 = &transport->fl.u.ip6;
212 int res;
213
214 pr_debug("%s: skb:%p, len:%d, src:%pI6 dst:%pI6\n", __func__, skb,
215 skb->len, &fl6->saddr, &fl6->daddr);
216
217 IP6_ECN_flow_xmit(sk, fl6->flowlabel);
218
219 if (!(transport->param_flags & SPP_PMTUD_ENABLE))
220 skb->ignore_df = 1;
221
222 SCTP_INC_STATS(sock_net(sk), SCTP_MIB_OUTSCTPPACKS);
223
224 rcu_read_lock();
225 res = ip6_xmit(sk, skb, fl6, sk->sk_mark, rcu_dereference(np->opt),
226 np->tclass);
227 rcu_read_unlock();
228 return res;
229}
230
231/* Returns the dst cache entry for the given source and destination ip
232 * addresses.
233 */
234static void sctp_v6_get_dst(struct sctp_transport *t, union sctp_addr *saddr,
235 struct flowi *fl, struct sock *sk)
236{
237 struct sctp_association *asoc = t->asoc;
238 struct dst_entry *dst = NULL;
239 struct flowi6 *fl6 = &fl->u.ip6;
240 struct sctp_bind_addr *bp;
241 struct ipv6_pinfo *np = inet6_sk(sk);
242 struct sctp_sockaddr_entry *laddr;
243 union sctp_addr *daddr = &t->ipaddr;
244 union sctp_addr dst_saddr;
245 struct in6_addr *final_p, final;
246 enum sctp_scope scope;
247 __u8 matchlen = 0;
248
249 memset(fl6, 0, sizeof(struct flowi6));
250 fl6->daddr = daddr->v6.sin6_addr;
251 fl6->fl6_dport = daddr->v6.sin6_port;
252 fl6->flowi6_proto = IPPROTO_SCTP;
253 if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
254 fl6->flowi6_oif = daddr->v6.sin6_scope_id;
255 else if (asoc)
256 fl6->flowi6_oif = asoc->base.sk->sk_bound_dev_if;
257
258 pr_debug("%s: dst=%pI6 ", __func__, &fl6->daddr);
259
260 if (asoc)
261 fl6->fl6_sport = htons(asoc->base.bind_addr.port);
262
263 if (saddr) {
264 fl6->saddr = saddr->v6.sin6_addr;
265 fl6->fl6_sport = saddr->v6.sin6_port;
266
267 pr_debug("src=%pI6 - ", &fl6->saddr);
268 }
269
270 rcu_read_lock();
271 final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final);
272 rcu_read_unlock();
273
274 dst = ip6_dst_lookup_flow(sk, fl6, final_p);
275 if (!asoc || saddr)
276 goto out;
277
278 bp = &asoc->base.bind_addr;
279 scope = sctp_scope(daddr);
280 /* ip6_dst_lookup has filled in the fl6->saddr for us. Check
281 * to see if we can use it.
282 */
283 if (!IS_ERR(dst)) {
284 /* Walk through the bind address list and look for a bind
285 * address that matches the source address of the returned dst.
286 */
287 sctp_v6_to_addr(&dst_saddr, &fl6->saddr, htons(bp->port));
288 rcu_read_lock();
289 list_for_each_entry_rcu(laddr, &bp->address_list, list) {
290 if (!laddr->valid || laddr->state == SCTP_ADDR_DEL ||
291 (laddr->state != SCTP_ADDR_SRC &&
292 !asoc->src_out_of_asoc_ok))
293 continue;
294
295 /* Do not compare against v4 addrs */
296 if ((laddr->a.sa.sa_family == AF_INET6) &&
297 (sctp_v6_cmp_addr(&dst_saddr, &laddr->a))) {
298 rcu_read_unlock();
299 goto out;
300 }
301 }
302 rcu_read_unlock();
303 /* None of the bound addresses match the source address of the
304 * dst. So release it.
305 */
306 dst_release(dst);
307 dst = NULL;
308 }
309
310 /* Walk through the bind address list and try to get the
311 * best source address for a given destination.
312 */
313 rcu_read_lock();
314 list_for_each_entry_rcu(laddr, &bp->address_list, list) {
315 struct dst_entry *bdst;
316 __u8 bmatchlen;
317
318 if (!laddr->valid ||
319 laddr->state != SCTP_ADDR_SRC ||
320 laddr->a.sa.sa_family != AF_INET6 ||
321 scope > sctp_scope(&laddr->a))
322 continue;
323
324 fl6->saddr = laddr->a.v6.sin6_addr;
325 fl6->fl6_sport = laddr->a.v6.sin6_port;
326 final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final);
327 bdst = ip6_dst_lookup_flow(sk, fl6, final_p);
328
329 if (IS_ERR(bdst))
330 continue;
331
332 if (ipv6_chk_addr(dev_net(bdst->dev),
333 &laddr->a.v6.sin6_addr, bdst->dev, 1)) {
334 if (!IS_ERR_OR_NULL(dst))
335 dst_release(dst);
336 dst = bdst;
337 break;
338 }
339
340 bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a);
341 if (matchlen > bmatchlen) {
342 dst_release(bdst);
343 continue;
344 }
345
346 if (!IS_ERR_OR_NULL(dst))
347 dst_release(dst);
348 dst = bdst;
349 matchlen = bmatchlen;
350 }
351 rcu_read_unlock();
352
353out:
354 if (!IS_ERR_OR_NULL(dst)) {
355 struct rt6_info *rt;
356
357 rt = (struct rt6_info *)dst;
358 t->dst = dst;
359 t->dst_cookie = rt6_get_cookie(rt);
360 pr_debug("rt6_dst:%pI6/%d rt6_src:%pI6\n",
361 &rt->rt6i_dst.addr, rt->rt6i_dst.plen,
362 &fl6->saddr);
363 } else {
364 t->dst = NULL;
365
366 pr_debug("no route\n");
367 }
368}
369
370/* Returns the number of consecutive initial bits that match in the 2 ipv6
371 * addresses.
372 */
373static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
374 union sctp_addr *s2)
375{
376 return ipv6_addr_diff(&s1->v6.sin6_addr, &s2->v6.sin6_addr);
377}
378
379/* Fills in the source address(saddr) based on the destination address(daddr)
380 * and asoc's bind address list.
381 */
382static void sctp_v6_get_saddr(struct sctp_sock *sk,
383 struct sctp_transport *t,
384 struct flowi *fl)
385{
386 struct flowi6 *fl6 = &fl->u.ip6;
387 union sctp_addr *saddr = &t->saddr;
388
389 pr_debug("%s: asoc:%p dst:%p\n", __func__, t->asoc, t->dst);
390
391 if (t->dst) {
392 saddr->v6.sin6_family = AF_INET6;
393 saddr->v6.sin6_addr = fl6->saddr;
394 }
395}
396
397/* Make a copy of all potential local addresses. */
398static void sctp_v6_copy_addrlist(struct list_head *addrlist,
399 struct net_device *dev)
400{
401 struct inet6_dev *in6_dev;
402 struct inet6_ifaddr *ifp;
403 struct sctp_sockaddr_entry *addr;
404
405 rcu_read_lock();
406 if ((in6_dev = __in6_dev_get(dev)) == NULL) {
407 rcu_read_unlock();
408 return;
409 }
410
411 read_lock_bh(&in6_dev->lock);
412 list_for_each_entry(ifp, &in6_dev->addr_list, if_list) {
413 /* Add the address to the local list. */
414 addr = kzalloc(sizeof(*addr), GFP_ATOMIC);
415 if (addr) {
416 addr->a.v6.sin6_family = AF_INET6;
417 addr->a.v6.sin6_port = 0;
418 addr->a.v6.sin6_addr = ifp->addr;
419 addr->a.v6.sin6_scope_id = dev->ifindex;
420 addr->valid = 1;
421 INIT_LIST_HEAD(&addr->list);
422 list_add_tail(&addr->list, addrlist);
423 }
424 }
425
426 read_unlock_bh(&in6_dev->lock);
427 rcu_read_unlock();
428}
429
430/* Copy over any ip options */
431static void sctp_v6_copy_ip_options(struct sock *sk, struct sock *newsk)
432{
433 struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
434 struct ipv6_txoptions *opt;
435
436 newnp = inet6_sk(newsk);
437
438 rcu_read_lock();
439 opt = rcu_dereference(np->opt);
440 if (opt) {
441 opt = ipv6_dup_options(newsk, opt);
442 if (!opt)
443 pr_err("%s: Failed to copy ip options\n", __func__);
444 }
445 RCU_INIT_POINTER(newnp->opt, opt);
446 rcu_read_unlock();
447}
448
449/* Account for the IP options */
450static int sctp_v6_ip_options_len(struct sock *sk)
451{
452 struct ipv6_pinfo *np = inet6_sk(sk);
453 struct ipv6_txoptions *opt;
454 int len = 0;
455
456 rcu_read_lock();
457 opt = rcu_dereference(np->opt);
458 if (opt)
459 len = opt->opt_flen + opt->opt_nflen;
460
461 rcu_read_unlock();
462 return len;
463}
464
465/* Initialize a sockaddr_storage from in incoming skb. */
466static void sctp_v6_from_skb(union sctp_addr *addr, struct sk_buff *skb,
467 int is_saddr)
468{
469 /* Always called on head skb, so this is safe */
470 struct sctphdr *sh = sctp_hdr(skb);
471 struct sockaddr_in6 *sa = &addr->v6;
472
473 addr->v6.sin6_family = AF_INET6;
474 addr->v6.sin6_flowinfo = 0; /* FIXME */
475 addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif;
476
477 if (is_saddr) {
478 sa->sin6_port = sh->source;
479 sa->sin6_addr = ipv6_hdr(skb)->saddr;
480 } else {
481 sa->sin6_port = sh->dest;
482 sa->sin6_addr = ipv6_hdr(skb)->daddr;
483 }
484}
485
486/* Initialize an sctp_addr from a socket. */
487static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk)
488{
489 addr->v6.sin6_family = AF_INET6;
490 addr->v6.sin6_port = 0;
491 addr->v6.sin6_addr = sk->sk_v6_rcv_saddr;
492}
493
494/* Initialize sk->sk_rcv_saddr from sctp_addr. */
495static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
496{
497 if (addr->sa.sa_family == AF_INET) {
498 sk->sk_v6_rcv_saddr.s6_addr32[0] = 0;
499 sk->sk_v6_rcv_saddr.s6_addr32[1] = 0;
500 sk->sk_v6_rcv_saddr.s6_addr32[2] = htonl(0x0000ffff);
501 sk->sk_v6_rcv_saddr.s6_addr32[3] =
502 addr->v4.sin_addr.s_addr;
503 } else {
504 sk->sk_v6_rcv_saddr = addr->v6.sin6_addr;
505 }
506}
507
508/* Initialize sk->sk_daddr from sctp_addr. */
509static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
510{
511 if (addr->sa.sa_family == AF_INET) {
512 sk->sk_v6_daddr.s6_addr32[0] = 0;
513 sk->sk_v6_daddr.s6_addr32[1] = 0;
514 sk->sk_v6_daddr.s6_addr32[2] = htonl(0x0000ffff);
515 sk->sk_v6_daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
516 } else {
517 sk->sk_v6_daddr = addr->v6.sin6_addr;
518 }
519}
520
521/* Initialize a sctp_addr from an address parameter. */
522static void sctp_v6_from_addr_param(union sctp_addr *addr,
523 union sctp_addr_param *param,
524 __be16 port, int iif)
525{
526 addr->v6.sin6_family = AF_INET6;
527 addr->v6.sin6_port = port;
528 addr->v6.sin6_flowinfo = 0; /* BUG */
529 addr->v6.sin6_addr = param->v6.addr;
530 addr->v6.sin6_scope_id = iif;
531}
532
533/* Initialize an address parameter from a sctp_addr and return the length
534 * of the address parameter.
535 */
536static int sctp_v6_to_addr_param(const union sctp_addr *addr,
537 union sctp_addr_param *param)
538{
539 int length = sizeof(struct sctp_ipv6addr_param);
540
541 param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS;
542 param->v6.param_hdr.length = htons(length);
543 param->v6.addr = addr->v6.sin6_addr;
544
545 return length;
546}
547
548/* Initialize a sctp_addr from struct in6_addr. */
549static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr,
550 __be16 port)
551{
552 addr->sa.sa_family = AF_INET6;
553 addr->v6.sin6_port = port;
554 addr->v6.sin6_flowinfo = 0;
555 addr->v6.sin6_addr = *saddr;
556 addr->v6.sin6_scope_id = 0;
557}
558
559static int __sctp_v6_cmp_addr(const union sctp_addr *addr1,
560 const union sctp_addr *addr2)
561{
562 if (addr1->sa.sa_family != addr2->sa.sa_family) {
563 if (addr1->sa.sa_family == AF_INET &&
564 addr2->sa.sa_family == AF_INET6 &&
565 ipv6_addr_v4mapped(&addr2->v6.sin6_addr) &&
566 addr2->v6.sin6_addr.s6_addr32[3] ==
567 addr1->v4.sin_addr.s_addr)
568 return 1;
569
570 if (addr2->sa.sa_family == AF_INET &&
571 addr1->sa.sa_family == AF_INET6 &&
572 ipv6_addr_v4mapped(&addr1->v6.sin6_addr) &&
573 addr1->v6.sin6_addr.s6_addr32[3] ==
574 addr2->v4.sin_addr.s_addr)
575 return 1;
576
577 return 0;
578 }
579
580 if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))
581 return 0;
582
583 /* If this is a linklocal address, compare the scope_id. */
584 if ((ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) &&
585 addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&
586 addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)
587 return 0;
588
589 return 1;
590}
591
592/* Compare addresses exactly.
593 * v4-mapped-v6 is also in consideration.
594 */
595static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
596 const union sctp_addr *addr2)
597{
598 return __sctp_v6_cmp_addr(addr1, addr2) &&
599 addr1->v6.sin6_port == addr2->v6.sin6_port;
600}
601
602/* Initialize addr struct to INADDR_ANY. */
603static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port)
604{
605 memset(addr, 0x00, sizeof(union sctp_addr));
606 addr->v6.sin6_family = AF_INET6;
607 addr->v6.sin6_port = port;
608}
609
610/* Is this a wildcard address? */
611static int sctp_v6_is_any(const union sctp_addr *addr)
612{
613 return ipv6_addr_any(&addr->v6.sin6_addr);
614}
615
616/* Should this be available for binding? */
617static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp)
618{
619 int type;
620 struct net *net = sock_net(&sp->inet.sk);
621 const struct in6_addr *in6 = (const struct in6_addr *)&addr->v6.sin6_addr;
622
623 type = ipv6_addr_type(in6);
624 if (IPV6_ADDR_ANY == type)
625 return 1;
626 if (type == IPV6_ADDR_MAPPED) {
627 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
628 return 0;
629 sctp_v6_map_v4(addr);
630 return sctp_get_af_specific(AF_INET)->available(addr, sp);
631 }
632 if (!(type & IPV6_ADDR_UNICAST))
633 return 0;
634
635 return sp->inet.freebind || net->ipv6.sysctl.ip_nonlocal_bind ||
636 ipv6_chk_addr(net, in6, NULL, 0);
637}
638
639/* This function checks if the address is a valid address to be used for
640 * SCTP.
641 *
642 * Output:
643 * Return 0 - If the address is a non-unicast or an illegal address.
644 * Return 1 - If the address is a unicast.
645 */
646static int sctp_v6_addr_valid(union sctp_addr *addr,
647 struct sctp_sock *sp,
648 const struct sk_buff *skb)
649{
650 int ret = ipv6_addr_type(&addr->v6.sin6_addr);
651
652 /* Support v4-mapped-v6 address. */
653 if (ret == IPV6_ADDR_MAPPED) {
654 /* Note: This routine is used in input, so v4-mapped-v6
655 * are disallowed here when there is no sctp_sock.
656 */
657 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
658 return 0;
659 sctp_v6_map_v4(addr);
660 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb);
661 }
662
663 /* Is this a non-unicast address */
664 if (!(ret & IPV6_ADDR_UNICAST))
665 return 0;
666
667 return 1;
668}
669
670/* What is the scope of 'addr'? */
671static enum sctp_scope sctp_v6_scope(union sctp_addr *addr)
672{
673 enum sctp_scope retval;
674 int v6scope;
675
676 /* The IPv6 scope is really a set of bit fields.
677 * See IFA_* in <net/if_inet6.h>. Map to a generic SCTP scope.
678 */
679
680 v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
681 switch (v6scope) {
682 case IFA_HOST:
683 retval = SCTP_SCOPE_LOOPBACK;
684 break;
685 case IFA_LINK:
686 retval = SCTP_SCOPE_LINK;
687 break;
688 case IFA_SITE:
689 retval = SCTP_SCOPE_PRIVATE;
690 break;
691 default:
692 retval = SCTP_SCOPE_GLOBAL;
693 break;
694 }
695
696 return retval;
697}
698
699/* Create and initialize a new sk for the socket to be returned by accept(). */
700static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
701 struct sctp_association *asoc,
702 bool kern)
703{
704 struct sock *newsk;
705 struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
706 struct sctp6_sock *newsctp6sk;
707
708 newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot, kern);
709 if (!newsk)
710 goto out;
711
712 sock_init_data(NULL, newsk);
713
714 sctp_copy_sock(newsk, sk, asoc);
715 sock_reset_flag(sk, SOCK_ZAPPED);
716
717 newsctp6sk = (struct sctp6_sock *)newsk;
718 inet_sk(newsk)->pinet6 = &newsctp6sk->inet6;
719
720 sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped;
721
722 newnp = inet6_sk(newsk);
723
724 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
725 newnp->ipv6_mc_list = NULL;
726 newnp->ipv6_ac_list = NULL;
727 newnp->ipv6_fl_list = NULL;
728
729 sctp_v6_copy_ip_options(sk, newsk);
730
731 /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
732 * and getpeername().
733 */
734 sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
735
736 newsk->sk_v6_rcv_saddr = sk->sk_v6_rcv_saddr;
737
738 sk_refcnt_debug_inc(newsk);
739
740 if (newsk->sk_prot->init(newsk)) {
741 sk_common_release(newsk);
742 newsk = NULL;
743 }
744
745out:
746 return newsk;
747}
748
749/* Format a sockaddr for return to user space. This makes sure the return is
750 * AF_INET or AF_INET6 depending on the SCTP_I_WANT_MAPPED_V4_ADDR option.
751 */
752static int sctp_v6_addr_to_user(struct sctp_sock *sp, union sctp_addr *addr)
753{
754 if (sp->v4mapped) {
755 if (addr->sa.sa_family == AF_INET)
756 sctp_v4_map_v6(addr);
757 } else {
758 if (addr->sa.sa_family == AF_INET6 &&
759 ipv6_addr_v4mapped(&addr->v6.sin6_addr))
760 sctp_v6_map_v4(addr);
761 }
762
763 if (addr->sa.sa_family == AF_INET) {
764 memset(addr->v4.sin_zero, 0, sizeof(addr->v4.sin_zero));
765 return sizeof(struct sockaddr_in);
766 }
767 return sizeof(struct sockaddr_in6);
768}
769
770/* Where did this skb come from? */
771static int sctp_v6_skb_iif(const struct sk_buff *skb)
772{
773 return IP6CB(skb)->iif;
774}
775
776/* Was this packet marked by Explicit Congestion Notification? */
777static int sctp_v6_is_ce(const struct sk_buff *skb)
778{
779 return *((__u32 *)(ipv6_hdr(skb))) & (__force __u32)htonl(1 << 20);
780}
781
782/* Dump the v6 addr to the seq file. */
783static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
784{
785 seq_printf(seq, "%pI6 ", &addr->v6.sin6_addr);
786}
787
788static void sctp_v6_ecn_capable(struct sock *sk)
789{
790 inet6_sk(sk)->tclass |= INET_ECN_ECT_0;
791}
792
793/* Initialize a PF_INET msgname from a ulpevent. */
794static void sctp_inet6_event_msgname(struct sctp_ulpevent *event,
795 char *msgname, int *addrlen)
796{
797 union sctp_addr *addr;
798 struct sctp_association *asoc;
799 union sctp_addr *paddr;
800
801 if (!msgname)
802 return;
803
804 addr = (union sctp_addr *)msgname;
805 asoc = event->asoc;
806 paddr = &asoc->peer.primary_addr;
807
808 if (paddr->sa.sa_family == AF_INET) {
809 addr->v4.sin_family = AF_INET;
810 addr->v4.sin_port = htons(asoc->peer.port);
811 addr->v4.sin_addr = paddr->v4.sin_addr;
812 } else {
813 addr->v6.sin6_family = AF_INET6;
814 addr->v6.sin6_flowinfo = 0;
815 if (ipv6_addr_type(&paddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
816 addr->v6.sin6_scope_id = paddr->v6.sin6_scope_id;
817 else
818 addr->v6.sin6_scope_id = 0;
819 addr->v6.sin6_port = htons(asoc->peer.port);
820 addr->v6.sin6_addr = paddr->v6.sin6_addr;
821 }
822
823 *addrlen = sctp_v6_addr_to_user(sctp_sk(asoc->base.sk), addr);
824}
825
826/* Initialize a msg_name from an inbound skb. */
827static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname,
828 int *addr_len)
829{
830 union sctp_addr *addr;
831 struct sctphdr *sh;
832
833 if (!msgname)
834 return;
835
836 addr = (union sctp_addr *)msgname;
837 sh = sctp_hdr(skb);
838
839 if (ip_hdr(skb)->version == 4) {
840 addr->v4.sin_family = AF_INET;
841 addr->v4.sin_port = sh->source;
842 addr->v4.sin_addr.s_addr = ip_hdr(skb)->saddr;
843 } else {
844 addr->v6.sin6_family = AF_INET6;
845 addr->v6.sin6_flowinfo = 0;
846 addr->v6.sin6_port = sh->source;
847 addr->v6.sin6_addr = ipv6_hdr(skb)->saddr;
848 if (ipv6_addr_type(&addr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
849 addr->v6.sin6_scope_id = sctp_v6_skb_iif(skb);
850 else
851 addr->v6.sin6_scope_id = 0;
852 }
853
854 *addr_len = sctp_v6_addr_to_user(sctp_sk(skb->sk), addr);
855}
856
857/* Do we support this AF? */
858static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp)
859{
860 switch (family) {
861 case AF_INET6:
862 return 1;
863 /* v4-mapped-v6 addresses */
864 case AF_INET:
865 if (!__ipv6_only_sock(sctp_opt2sk(sp)))
866 return 1;
867 /* fallthru */
868 default:
869 return 0;
870 }
871}
872
873/* Address matching with wildcards allowed. This extra level
874 * of indirection lets us choose whether a PF_INET6 should
875 * disallow any v4 addresses if we so choose.
876 */
877static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
878 const union sctp_addr *addr2,
879 struct sctp_sock *opt)
880{
881 struct sock *sk = sctp_opt2sk(opt);
882 struct sctp_af *af1, *af2;
883
884 af1 = sctp_get_af_specific(addr1->sa.sa_family);
885 af2 = sctp_get_af_specific(addr2->sa.sa_family);
886
887 if (!af1 || !af2)
888 return 0;
889
890 /* If the socket is IPv6 only, v4 addrs will not match */
891 if (__ipv6_only_sock(sk) && af1 != af2)
892 return 0;
893
894 /* Today, wildcard AF_INET/AF_INET6. */
895 if (sctp_is_any(sk, addr1) || sctp_is_any(sk, addr2))
896 return 1;
897
898 if (addr1->sa.sa_family == AF_INET && addr2->sa.sa_family == AF_INET)
899 return addr1->v4.sin_addr.s_addr == addr2->v4.sin_addr.s_addr;
900
901 return __sctp_v6_cmp_addr(addr1, addr2);
902}
903
904/* Verify that the provided sockaddr looks bindable. Common verification,
905 * has already been taken care of.
906 */
907static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
908{
909 struct sctp_af *af;
910
911 /* ASSERT: address family has already been verified. */
912 if (addr->sa.sa_family != AF_INET6)
913 af = sctp_get_af_specific(addr->sa.sa_family);
914 else {
915 int type = ipv6_addr_type(&addr->v6.sin6_addr);
916 struct net_device *dev;
917
918 if (type & IPV6_ADDR_LINKLOCAL) {
919 struct net *net;
920 if (!addr->v6.sin6_scope_id)
921 return 0;
922 net = sock_net(&opt->inet.sk);
923 rcu_read_lock();
924 dev = dev_get_by_index_rcu(net, addr->v6.sin6_scope_id);
925 if (!dev || !(opt->inet.freebind ||
926 net->ipv6.sysctl.ip_nonlocal_bind ||
927 ipv6_chk_addr(net, &addr->v6.sin6_addr,
928 dev, 0))) {
929 rcu_read_unlock();
930 return 0;
931 }
932 rcu_read_unlock();
933 }
934
935 af = opt->pf->af;
936 }
937 return af->available(addr, opt);
938}
939
940/* Verify that the provided sockaddr looks sendable. Common verification,
941 * has already been taken care of.
942 */
943static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
944{
945 struct sctp_af *af = NULL;
946
947 /* ASSERT: address family has already been verified. */
948 if (addr->sa.sa_family != AF_INET6)
949 af = sctp_get_af_specific(addr->sa.sa_family);
950 else {
951 int type = ipv6_addr_type(&addr->v6.sin6_addr);
952 struct net_device *dev;
953
954 if (type & IPV6_ADDR_LINKLOCAL) {
955 if (!addr->v6.sin6_scope_id)
956 return 0;
957 rcu_read_lock();
958 dev = dev_get_by_index_rcu(sock_net(&opt->inet.sk),
959 addr->v6.sin6_scope_id);
960 rcu_read_unlock();
961 if (!dev)
962 return 0;
963 }
964 af = opt->pf->af;
965 }
966
967 return af != NULL;
968}
969
970/* Fill in Supported Address Type information for INIT and INIT-ACK
971 * chunks. Note: In the future, we may want to look at sock options
972 * to determine whether a PF_INET6 socket really wants to have IPV4
973 * addresses.
974 * Returns number of addresses supported.
975 */
976static int sctp_inet6_supported_addrs(const struct sctp_sock *opt,
977 __be16 *types)
978{
979 types[0] = SCTP_PARAM_IPV6_ADDRESS;
980 if (!opt || !ipv6_only_sock(sctp_opt2sk(opt))) {
981 types[1] = SCTP_PARAM_IPV4_ADDRESS;
982 return 2;
983 }
984 return 1;
985}
986
987/* Handle SCTP_I_WANT_MAPPED_V4_ADDR for getpeername() and getsockname() */
988static int sctp_getname(struct socket *sock, struct sockaddr *uaddr,
989 int peer)
990{
991 int rc;
992
993 rc = inet6_getname(sock, uaddr, peer);
994
995 if (rc < 0)
996 return rc;
997
998 rc = sctp_v6_addr_to_user(sctp_sk(sock->sk),
999 (union sctp_addr *)uaddr);
1000
1001 return rc;
1002}
1003
1004static const struct proto_ops inet6_seqpacket_ops = {
1005 .family = PF_INET6,
1006 .owner = THIS_MODULE,
1007 .release = inet6_release,
1008 .bind = inet6_bind,
1009 .connect = sctp_inet_connect,
1010 .socketpair = sock_no_socketpair,
1011 .accept = inet_accept,
1012 .getname = sctp_getname,
1013 .poll = sctp_poll,
1014 .ioctl = inet6_ioctl,
1015 .listen = sctp_inet_listen,
1016 .shutdown = inet_shutdown,
1017 .setsockopt = sock_common_setsockopt,
1018 .getsockopt = sock_common_getsockopt,
1019 .sendmsg = inet_sendmsg,
1020 .recvmsg = inet_recvmsg,
1021 .mmap = sock_no_mmap,
1022#ifdef CONFIG_COMPAT
1023 .compat_setsockopt = compat_sock_common_setsockopt,
1024 .compat_getsockopt = compat_sock_common_getsockopt,
1025#endif
1026};
1027
1028static struct inet_protosw sctpv6_seqpacket_protosw = {
1029 .type = SOCK_SEQPACKET,
1030 .protocol = IPPROTO_SCTP,
1031 .prot = &sctpv6_prot,
1032 .ops = &inet6_seqpacket_ops,
1033 .flags = SCTP_PROTOSW_FLAG
1034};
1035static struct inet_protosw sctpv6_stream_protosw = {
1036 .type = SOCK_STREAM,
1037 .protocol = IPPROTO_SCTP,
1038 .prot = &sctpv6_prot,
1039 .ops = &inet6_seqpacket_ops,
1040 .flags = SCTP_PROTOSW_FLAG,
1041};
1042
1043static int sctp6_rcv(struct sk_buff *skb)
1044{
1045 return sctp_rcv(skb) ? -1 : 0;
1046}
1047
1048static const struct inet6_protocol sctpv6_protocol = {
1049 .handler = sctp6_rcv,
1050 .err_handler = sctp_v6_err,
1051 .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
1052};
1053
1054static struct sctp_af sctp_af_inet6 = {
1055 .sa_family = AF_INET6,
1056 .sctp_xmit = sctp_v6_xmit,
1057 .setsockopt = ipv6_setsockopt,
1058 .getsockopt = ipv6_getsockopt,
1059 .get_dst = sctp_v6_get_dst,
1060 .get_saddr = sctp_v6_get_saddr,
1061 .copy_addrlist = sctp_v6_copy_addrlist,
1062 .from_skb = sctp_v6_from_skb,
1063 .from_sk = sctp_v6_from_sk,
1064 .from_addr_param = sctp_v6_from_addr_param,
1065 .to_addr_param = sctp_v6_to_addr_param,
1066 .cmp_addr = sctp_v6_cmp_addr,
1067 .scope = sctp_v6_scope,
1068 .addr_valid = sctp_v6_addr_valid,
1069 .inaddr_any = sctp_v6_inaddr_any,
1070 .is_any = sctp_v6_is_any,
1071 .available = sctp_v6_available,
1072 .skb_iif = sctp_v6_skb_iif,
1073 .is_ce = sctp_v6_is_ce,
1074 .seq_dump_addr = sctp_v6_seq_dump_addr,
1075 .ecn_capable = sctp_v6_ecn_capable,
1076 .net_header_len = sizeof(struct ipv6hdr),
1077 .sockaddr_len = sizeof(struct sockaddr_in6),
1078 .ip_options_len = sctp_v6_ip_options_len,
1079#ifdef CONFIG_COMPAT
1080 .compat_setsockopt = compat_ipv6_setsockopt,
1081 .compat_getsockopt = compat_ipv6_getsockopt,
1082#endif
1083};
1084
1085static struct sctp_pf sctp_pf_inet6 = {
1086 .event_msgname = sctp_inet6_event_msgname,
1087 .skb_msgname = sctp_inet6_skb_msgname,
1088 .af_supported = sctp_inet6_af_supported,
1089 .cmp_addr = sctp_inet6_cmp_addr,
1090 .bind_verify = sctp_inet6_bind_verify,
1091 .send_verify = sctp_inet6_send_verify,
1092 .supported_addrs = sctp_inet6_supported_addrs,
1093 .create_accept_sk = sctp_v6_create_accept_sk,
1094 .addr_to_user = sctp_v6_addr_to_user,
1095 .to_sk_saddr = sctp_v6_to_sk_saddr,
1096 .to_sk_daddr = sctp_v6_to_sk_daddr,
1097 .copy_ip_options = sctp_v6_copy_ip_options,
1098 .af = &sctp_af_inet6,
1099};
1100
1101/* Initialize IPv6 support and register with socket layer. */
1102void sctp_v6_pf_init(void)
1103{
1104 /* Register the SCTP specific PF_INET6 functions. */
1105 sctp_register_pf(&sctp_pf_inet6, PF_INET6);
1106
1107 /* Register the SCTP specific AF_INET6 functions. */
1108 sctp_register_af(&sctp_af_inet6);
1109}
1110
1111void sctp_v6_pf_exit(void)
1112{
1113 list_del(&sctp_af_inet6.list);
1114}
1115
1116/* Initialize IPv6 support and register with socket layer. */
1117int sctp_v6_protosw_init(void)
1118{
1119 int rc;
1120
1121 rc = proto_register(&sctpv6_prot, 1);
1122 if (rc)
1123 return rc;
1124
1125 /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
1126 inet6_register_protosw(&sctpv6_seqpacket_protosw);
1127 inet6_register_protosw(&sctpv6_stream_protosw);
1128
1129 return 0;
1130}
1131
1132void sctp_v6_protosw_exit(void)
1133{
1134 inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
1135 inet6_unregister_protosw(&sctpv6_stream_protosw);
1136 proto_unregister(&sctpv6_prot);
1137}
1138
1139
1140/* Register with inet6 layer. */
1141int sctp_v6_add_protocol(void)
1142{
1143 /* Register notifier for inet6 address additions/deletions. */
1144 register_inet6addr_notifier(&sctp_inet6addr_notifier);
1145
1146 if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
1147 return -EAGAIN;
1148
1149 return 0;
1150}
1151
1152/* Unregister with inet6 layer. */
1153void sctp_v6_del_protocol(void)
1154{
1155 inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
1156 unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
1157}
1// SPDX-License-Identifier: GPL-2.0-or-later
2/* SCTP kernel implementation
3 * (C) Copyright IBM Corp. 2002, 2004
4 * Copyright (c) 2001 Nokia, Inc.
5 * Copyright (c) 2001 La Monte H.P. Yarroll
6 * Copyright (c) 2002-2003 Intel Corp.
7 *
8 * This file is part of the SCTP kernel implementation
9 *
10 * SCTP over IPv6.
11 *
12 * Please send any bug reports or fixes you make to the
13 * email address(es):
14 * lksctp developers <linux-sctp@vger.kernel.org>
15 *
16 * Written or modified by:
17 * Le Yanqun <yanqun.le@nokia.com>
18 * Hui Huang <hui.huang@nokia.com>
19 * La Monte H.P. Yarroll <piggy@acm.org>
20 * Sridhar Samudrala <sri@us.ibm.com>
21 * Jon Grimm <jgrimm@us.ibm.com>
22 * Ardelle Fan <ardelle.fan@intel.com>
23 *
24 * Based on:
25 * linux/net/ipv6/tcp_ipv6.c
26 */
27
28#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
29
30#include <linux/module.h>
31#include <linux/errno.h>
32#include <linux/types.h>
33#include <linux/socket.h>
34#include <linux/sockios.h>
35#include <linux/net.h>
36#include <linux/in.h>
37#include <linux/in6.h>
38#include <linux/netdevice.h>
39#include <linux/init.h>
40#include <linux/ipsec.h>
41#include <linux/slab.h>
42
43#include <linux/ipv6.h>
44#include <linux/icmpv6.h>
45#include <linux/random.h>
46#include <linux/seq_file.h>
47
48#include <net/protocol.h>
49#include <net/ndisc.h>
50#include <net/ip.h>
51#include <net/ipv6.h>
52#include <net/transp_v6.h>
53#include <net/addrconf.h>
54#include <net/ip6_route.h>
55#include <net/inet_common.h>
56#include <net/inet_ecn.h>
57#include <net/sctp/sctp.h>
58#include <net/udp_tunnel.h>
59
60#include <linux/uaccess.h>
61
62static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
63 union sctp_addr *s2);
64static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr,
65 __be16 port);
66static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
67 const union sctp_addr *addr2);
68
69/* Event handler for inet6 address addition/deletion events.
70 * The sctp_local_addr_list needs to be protocted by a spin lock since
71 * multiple notifiers (say IPv4 and IPv6) may be running at the same
72 * time and thus corrupt the list.
73 * The reader side is protected with RCU.
74 */
75static int sctp_inet6addr_event(struct notifier_block *this, unsigned long ev,
76 void *ptr)
77{
78 struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
79 struct sctp_sockaddr_entry *addr = NULL;
80 struct sctp_sockaddr_entry *temp;
81 struct net *net = dev_net(ifa->idev->dev);
82 int found = 0;
83
84 switch (ev) {
85 case NETDEV_UP:
86 addr = kzalloc(sizeof(*addr), GFP_ATOMIC);
87 if (addr) {
88 addr->a.v6.sin6_family = AF_INET6;
89 addr->a.v6.sin6_addr = ifa->addr;
90 addr->a.v6.sin6_scope_id = ifa->idev->dev->ifindex;
91 addr->valid = 1;
92 spin_lock_bh(&net->sctp.local_addr_lock);
93 list_add_tail_rcu(&addr->list, &net->sctp.local_addr_list);
94 sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_NEW);
95 spin_unlock_bh(&net->sctp.local_addr_lock);
96 }
97 break;
98 case NETDEV_DOWN:
99 spin_lock_bh(&net->sctp.local_addr_lock);
100 list_for_each_entry_safe(addr, temp,
101 &net->sctp.local_addr_list, list) {
102 if (addr->a.sa.sa_family == AF_INET6 &&
103 ipv6_addr_equal(&addr->a.v6.sin6_addr,
104 &ifa->addr) &&
105 addr->a.v6.sin6_scope_id == ifa->idev->dev->ifindex) {
106 sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_DEL);
107 found = 1;
108 addr->valid = 0;
109 list_del_rcu(&addr->list);
110 break;
111 }
112 }
113 spin_unlock_bh(&net->sctp.local_addr_lock);
114 if (found)
115 kfree_rcu(addr, rcu);
116 break;
117 }
118
119 return NOTIFY_DONE;
120}
121
122static struct notifier_block sctp_inet6addr_notifier = {
123 .notifier_call = sctp_inet6addr_event,
124};
125
126static void sctp_v6_err_handle(struct sctp_transport *t, struct sk_buff *skb,
127 __u8 type, __u8 code, __u32 info)
128{
129 struct sctp_association *asoc = t->asoc;
130 struct sock *sk = asoc->base.sk;
131 struct ipv6_pinfo *np;
132 int err = 0;
133
134 switch (type) {
135 case ICMPV6_PKT_TOOBIG:
136 if (ip6_sk_accept_pmtu(sk))
137 sctp_icmp_frag_needed(sk, asoc, t, info);
138 return;
139 case ICMPV6_PARAMPROB:
140 if (ICMPV6_UNK_NEXTHDR == code) {
141 sctp_icmp_proto_unreachable(sk, asoc, t);
142 return;
143 }
144 break;
145 case NDISC_REDIRECT:
146 sctp_icmp_redirect(sk, t, skb);
147 return;
148 default:
149 break;
150 }
151
152 np = inet6_sk(sk);
153 icmpv6_err_convert(type, code, &err);
154 if (!sock_owned_by_user(sk) && np->recverr) {
155 sk->sk_err = err;
156 sk_error_report(sk);
157 } else {
158 sk->sk_err_soft = err;
159 }
160}
161
162/* ICMP error handler. */
163static int sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
164 u8 type, u8 code, int offset, __be32 info)
165{
166 struct net *net = dev_net(skb->dev);
167 struct sctp_transport *transport;
168 struct sctp_association *asoc;
169 __u16 saveip, savesctp;
170 struct sock *sk;
171
172 /* Fix up skb to look at the embedded net header. */
173 saveip = skb->network_header;
174 savesctp = skb->transport_header;
175 skb_reset_network_header(skb);
176 skb_set_transport_header(skb, offset);
177 sk = sctp_err_lookup(net, AF_INET6, skb, sctp_hdr(skb), &asoc, &transport);
178 /* Put back, the original pointers. */
179 skb->network_header = saveip;
180 skb->transport_header = savesctp;
181 if (!sk) {
182 __ICMP6_INC_STATS(net, __in6_dev_get(skb->dev), ICMP6_MIB_INERRORS);
183 return -ENOENT;
184 }
185
186 sctp_v6_err_handle(transport, skb, type, code, ntohl(info));
187 sctp_err_finish(sk, transport);
188
189 return 0;
190}
191
192int sctp_udp_v6_err(struct sock *sk, struct sk_buff *skb)
193{
194 struct net *net = dev_net(skb->dev);
195 struct sctp_association *asoc;
196 struct sctp_transport *t;
197 struct icmp6hdr *hdr;
198 __u32 info = 0;
199
200 skb->transport_header += sizeof(struct udphdr);
201 sk = sctp_err_lookup(net, AF_INET6, skb, sctp_hdr(skb), &asoc, &t);
202 if (!sk) {
203 __ICMP6_INC_STATS(net, __in6_dev_get(skb->dev), ICMP6_MIB_INERRORS);
204 return -ENOENT;
205 }
206
207 skb->transport_header -= sizeof(struct udphdr);
208 hdr = (struct icmp6hdr *)(skb_network_header(skb) - sizeof(struct icmp6hdr));
209 if (hdr->icmp6_type == NDISC_REDIRECT) {
210 /* can't be handled without outer ip6hdr known, leave it to udpv6_err */
211 sctp_err_finish(sk, t);
212 return 0;
213 }
214 if (hdr->icmp6_type == ICMPV6_PKT_TOOBIG)
215 info = ntohl(hdr->icmp6_mtu);
216 sctp_v6_err_handle(t, skb, hdr->icmp6_type, hdr->icmp6_code, info);
217
218 sctp_err_finish(sk, t);
219 return 1;
220}
221
222static int sctp_v6_xmit(struct sk_buff *skb, struct sctp_transport *t)
223{
224 struct dst_entry *dst = dst_clone(t->dst);
225 struct flowi6 *fl6 = &t->fl.u.ip6;
226 struct sock *sk = skb->sk;
227 struct ipv6_pinfo *np = inet6_sk(sk);
228 __u8 tclass = np->tclass;
229 __be32 label;
230
231 pr_debug("%s: skb:%p, len:%d, src:%pI6 dst:%pI6\n", __func__, skb,
232 skb->len, &fl6->saddr, &fl6->daddr);
233
234 if (t->dscp & SCTP_DSCP_SET_MASK)
235 tclass = t->dscp & SCTP_DSCP_VAL_MASK;
236
237 if (INET_ECN_is_capable(tclass))
238 IP6_ECN_flow_xmit(sk, fl6->flowlabel);
239
240 if (!(t->param_flags & SPP_PMTUD_ENABLE))
241 skb->ignore_df = 1;
242
243 SCTP_INC_STATS(sock_net(sk), SCTP_MIB_OUTSCTPPACKS);
244
245 if (!t->encap_port || !sctp_sk(sk)->udp_port) {
246 int res;
247
248 skb_dst_set(skb, dst);
249 rcu_read_lock();
250 res = ip6_xmit(sk, skb, fl6, sk->sk_mark,
251 rcu_dereference(np->opt),
252 tclass, sk->sk_priority);
253 rcu_read_unlock();
254 return res;
255 }
256
257 if (skb_is_gso(skb))
258 skb_shinfo(skb)->gso_type |= SKB_GSO_UDP_TUNNEL_CSUM;
259
260 skb->encapsulation = 1;
261 skb_reset_inner_mac_header(skb);
262 skb_reset_inner_transport_header(skb);
263 skb_set_inner_ipproto(skb, IPPROTO_SCTP);
264 label = ip6_make_flowlabel(sock_net(sk), skb, fl6->flowlabel, true, fl6);
265
266 return udp_tunnel6_xmit_skb(dst, sk, skb, NULL, &fl6->saddr,
267 &fl6->daddr, tclass, ip6_dst_hoplimit(dst),
268 label, sctp_sk(sk)->udp_port, t->encap_port, false);
269}
270
271/* Returns the dst cache entry for the given source and destination ip
272 * addresses.
273 */
274static void sctp_v6_get_dst(struct sctp_transport *t, union sctp_addr *saddr,
275 struct flowi *fl, struct sock *sk)
276{
277 struct sctp_association *asoc = t->asoc;
278 struct dst_entry *dst = NULL;
279 struct flowi _fl;
280 struct flowi6 *fl6 = &_fl.u.ip6;
281 struct sctp_bind_addr *bp;
282 struct ipv6_pinfo *np = inet6_sk(sk);
283 struct sctp_sockaddr_entry *laddr;
284 union sctp_addr *daddr = &t->ipaddr;
285 union sctp_addr dst_saddr;
286 struct in6_addr *final_p, final;
287 enum sctp_scope scope;
288 __u8 matchlen = 0;
289
290 memset(&_fl, 0, sizeof(_fl));
291 fl6->daddr = daddr->v6.sin6_addr;
292 fl6->fl6_dport = daddr->v6.sin6_port;
293 fl6->flowi6_proto = IPPROTO_SCTP;
294 if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
295 fl6->flowi6_oif = daddr->v6.sin6_scope_id;
296 else if (asoc)
297 fl6->flowi6_oif = asoc->base.sk->sk_bound_dev_if;
298 if (t->flowlabel & SCTP_FLOWLABEL_SET_MASK)
299 fl6->flowlabel = htonl(t->flowlabel & SCTP_FLOWLABEL_VAL_MASK);
300
301 if (np->sndflow && (fl6->flowlabel & IPV6_FLOWLABEL_MASK)) {
302 struct ip6_flowlabel *flowlabel;
303
304 flowlabel = fl6_sock_lookup(sk, fl6->flowlabel);
305 if (IS_ERR(flowlabel))
306 goto out;
307 fl6_sock_release(flowlabel);
308 }
309
310 pr_debug("%s: dst=%pI6 ", __func__, &fl6->daddr);
311
312 if (asoc)
313 fl6->fl6_sport = htons(asoc->base.bind_addr.port);
314
315 if (saddr) {
316 fl6->saddr = saddr->v6.sin6_addr;
317 if (!fl6->fl6_sport)
318 fl6->fl6_sport = saddr->v6.sin6_port;
319
320 pr_debug("src=%pI6 - ", &fl6->saddr);
321 }
322
323 rcu_read_lock();
324 final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final);
325 rcu_read_unlock();
326
327 dst = ip6_dst_lookup_flow(sock_net(sk), sk, fl6, final_p);
328 if (!asoc || saddr) {
329 t->dst = dst;
330 memcpy(fl, &_fl, sizeof(_fl));
331 goto out;
332 }
333
334 bp = &asoc->base.bind_addr;
335 scope = sctp_scope(daddr);
336 /* ip6_dst_lookup has filled in the fl6->saddr for us. Check
337 * to see if we can use it.
338 */
339 if (!IS_ERR(dst)) {
340 /* Walk through the bind address list and look for a bind
341 * address that matches the source address of the returned dst.
342 */
343 sctp_v6_to_addr(&dst_saddr, &fl6->saddr, htons(bp->port));
344 rcu_read_lock();
345 list_for_each_entry_rcu(laddr, &bp->address_list, list) {
346 if (!laddr->valid || laddr->state == SCTP_ADDR_DEL ||
347 (laddr->state != SCTP_ADDR_SRC &&
348 !asoc->src_out_of_asoc_ok))
349 continue;
350
351 /* Do not compare against v4 addrs */
352 if ((laddr->a.sa.sa_family == AF_INET6) &&
353 (sctp_v6_cmp_addr(&dst_saddr, &laddr->a))) {
354 rcu_read_unlock();
355 t->dst = dst;
356 memcpy(fl, &_fl, sizeof(_fl));
357 goto out;
358 }
359 }
360 rcu_read_unlock();
361 /* None of the bound addresses match the source address of the
362 * dst. So release it.
363 */
364 dst_release(dst);
365 dst = NULL;
366 }
367
368 /* Walk through the bind address list and try to get the
369 * best source address for a given destination.
370 */
371 rcu_read_lock();
372 list_for_each_entry_rcu(laddr, &bp->address_list, list) {
373 struct dst_entry *bdst;
374 __u8 bmatchlen;
375
376 if (!laddr->valid ||
377 laddr->state != SCTP_ADDR_SRC ||
378 laddr->a.sa.sa_family != AF_INET6 ||
379 scope > sctp_scope(&laddr->a))
380 continue;
381
382 fl6->saddr = laddr->a.v6.sin6_addr;
383 fl6->fl6_sport = laddr->a.v6.sin6_port;
384 final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final);
385 bdst = ip6_dst_lookup_flow(sock_net(sk), sk, fl6, final_p);
386
387 if (IS_ERR(bdst))
388 continue;
389
390 if (ipv6_chk_addr(dev_net(bdst->dev),
391 &laddr->a.v6.sin6_addr, bdst->dev, 1)) {
392 if (!IS_ERR_OR_NULL(dst))
393 dst_release(dst);
394 dst = bdst;
395 t->dst = dst;
396 memcpy(fl, &_fl, sizeof(_fl));
397 break;
398 }
399
400 bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a);
401 if (matchlen > bmatchlen) {
402 dst_release(bdst);
403 continue;
404 }
405
406 if (!IS_ERR_OR_NULL(dst))
407 dst_release(dst);
408 dst = bdst;
409 matchlen = bmatchlen;
410 t->dst = dst;
411 memcpy(fl, &_fl, sizeof(_fl));
412 }
413 rcu_read_unlock();
414
415out:
416 if (!IS_ERR_OR_NULL(dst)) {
417 struct rt6_info *rt;
418
419 rt = (struct rt6_info *)dst;
420 t->dst_cookie = rt6_get_cookie(rt);
421 pr_debug("rt6_dst:%pI6/%d rt6_src:%pI6\n",
422 &rt->rt6i_dst.addr, rt->rt6i_dst.plen,
423 &fl->u.ip6.saddr);
424 } else {
425 t->dst = NULL;
426 pr_debug("no route\n");
427 }
428}
429
430/* Returns the number of consecutive initial bits that match in the 2 ipv6
431 * addresses.
432 */
433static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
434 union sctp_addr *s2)
435{
436 return ipv6_addr_diff(&s1->v6.sin6_addr, &s2->v6.sin6_addr);
437}
438
439/* Fills in the source address(saddr) based on the destination address(daddr)
440 * and asoc's bind address list.
441 */
442static void sctp_v6_get_saddr(struct sctp_sock *sk,
443 struct sctp_transport *t,
444 struct flowi *fl)
445{
446 struct flowi6 *fl6 = &fl->u.ip6;
447 union sctp_addr *saddr = &t->saddr;
448
449 pr_debug("%s: asoc:%p dst:%p\n", __func__, t->asoc, t->dst);
450
451 if (t->dst) {
452 saddr->v6.sin6_family = AF_INET6;
453 saddr->v6.sin6_addr = fl6->saddr;
454 }
455}
456
457/* Make a copy of all potential local addresses. */
458static void sctp_v6_copy_addrlist(struct list_head *addrlist,
459 struct net_device *dev)
460{
461 struct inet6_dev *in6_dev;
462 struct inet6_ifaddr *ifp;
463 struct sctp_sockaddr_entry *addr;
464
465 rcu_read_lock();
466 if ((in6_dev = __in6_dev_get(dev)) == NULL) {
467 rcu_read_unlock();
468 return;
469 }
470
471 read_lock_bh(&in6_dev->lock);
472 list_for_each_entry(ifp, &in6_dev->addr_list, if_list) {
473 /* Add the address to the local list. */
474 addr = kzalloc(sizeof(*addr), GFP_ATOMIC);
475 if (addr) {
476 addr->a.v6.sin6_family = AF_INET6;
477 addr->a.v6.sin6_addr = ifp->addr;
478 addr->a.v6.sin6_scope_id = dev->ifindex;
479 addr->valid = 1;
480 INIT_LIST_HEAD(&addr->list);
481 list_add_tail(&addr->list, addrlist);
482 }
483 }
484
485 read_unlock_bh(&in6_dev->lock);
486 rcu_read_unlock();
487}
488
489/* Copy over any ip options */
490static void sctp_v6_copy_ip_options(struct sock *sk, struct sock *newsk)
491{
492 struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
493 struct ipv6_txoptions *opt;
494
495 newnp = inet6_sk(newsk);
496
497 rcu_read_lock();
498 opt = rcu_dereference(np->opt);
499 if (opt) {
500 opt = ipv6_dup_options(newsk, opt);
501 if (!opt)
502 pr_err("%s: Failed to copy ip options\n", __func__);
503 }
504 RCU_INIT_POINTER(newnp->opt, opt);
505 rcu_read_unlock();
506}
507
508/* Account for the IP options */
509static int sctp_v6_ip_options_len(struct sock *sk)
510{
511 struct ipv6_pinfo *np = inet6_sk(sk);
512 struct ipv6_txoptions *opt;
513 int len = 0;
514
515 rcu_read_lock();
516 opt = rcu_dereference(np->opt);
517 if (opt)
518 len = opt->opt_flen + opt->opt_nflen;
519
520 rcu_read_unlock();
521 return len;
522}
523
524/* Initialize a sockaddr_storage from in incoming skb. */
525static void sctp_v6_from_skb(union sctp_addr *addr, struct sk_buff *skb,
526 int is_saddr)
527{
528 /* Always called on head skb, so this is safe */
529 struct sctphdr *sh = sctp_hdr(skb);
530 struct sockaddr_in6 *sa = &addr->v6;
531
532 addr->v6.sin6_family = AF_INET6;
533 addr->v6.sin6_flowinfo = 0; /* FIXME */
534 addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif;
535
536 if (is_saddr) {
537 sa->sin6_port = sh->source;
538 sa->sin6_addr = ipv6_hdr(skb)->saddr;
539 } else {
540 sa->sin6_port = sh->dest;
541 sa->sin6_addr = ipv6_hdr(skb)->daddr;
542 }
543}
544
545/* Initialize an sctp_addr from a socket. */
546static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk)
547{
548 addr->v6.sin6_family = AF_INET6;
549 addr->v6.sin6_port = 0;
550 addr->v6.sin6_addr = sk->sk_v6_rcv_saddr;
551}
552
553/* Initialize sk->sk_rcv_saddr from sctp_addr. */
554static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
555{
556 if (addr->sa.sa_family == AF_INET) {
557 sk->sk_v6_rcv_saddr.s6_addr32[0] = 0;
558 sk->sk_v6_rcv_saddr.s6_addr32[1] = 0;
559 sk->sk_v6_rcv_saddr.s6_addr32[2] = htonl(0x0000ffff);
560 sk->sk_v6_rcv_saddr.s6_addr32[3] =
561 addr->v4.sin_addr.s_addr;
562 } else {
563 sk->sk_v6_rcv_saddr = addr->v6.sin6_addr;
564 }
565}
566
567/* Initialize sk->sk_daddr from sctp_addr. */
568static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
569{
570 if (addr->sa.sa_family == AF_INET) {
571 sk->sk_v6_daddr.s6_addr32[0] = 0;
572 sk->sk_v6_daddr.s6_addr32[1] = 0;
573 sk->sk_v6_daddr.s6_addr32[2] = htonl(0x0000ffff);
574 sk->sk_v6_daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
575 } else {
576 sk->sk_v6_daddr = addr->v6.sin6_addr;
577 }
578}
579
580/* Initialize a sctp_addr from an address parameter. */
581static bool sctp_v6_from_addr_param(union sctp_addr *addr,
582 union sctp_addr_param *param,
583 __be16 port, int iif)
584{
585 if (ntohs(param->v6.param_hdr.length) < sizeof(struct sctp_ipv6addr_param))
586 return false;
587
588 addr->v6.sin6_family = AF_INET6;
589 addr->v6.sin6_port = port;
590 addr->v6.sin6_flowinfo = 0; /* BUG */
591 addr->v6.sin6_addr = param->v6.addr;
592 addr->v6.sin6_scope_id = iif;
593
594 return true;
595}
596
597/* Initialize an address parameter from a sctp_addr and return the length
598 * of the address parameter.
599 */
600static int sctp_v6_to_addr_param(const union sctp_addr *addr,
601 union sctp_addr_param *param)
602{
603 int length = sizeof(struct sctp_ipv6addr_param);
604
605 param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS;
606 param->v6.param_hdr.length = htons(length);
607 param->v6.addr = addr->v6.sin6_addr;
608
609 return length;
610}
611
612/* Initialize a sctp_addr from struct in6_addr. */
613static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr,
614 __be16 port)
615{
616 addr->sa.sa_family = AF_INET6;
617 addr->v6.sin6_port = port;
618 addr->v6.sin6_flowinfo = 0;
619 addr->v6.sin6_addr = *saddr;
620 addr->v6.sin6_scope_id = 0;
621}
622
623static int __sctp_v6_cmp_addr(const union sctp_addr *addr1,
624 const union sctp_addr *addr2)
625{
626 if (addr1->sa.sa_family != addr2->sa.sa_family) {
627 if (addr1->sa.sa_family == AF_INET &&
628 addr2->sa.sa_family == AF_INET6 &&
629 ipv6_addr_v4mapped(&addr2->v6.sin6_addr) &&
630 addr2->v6.sin6_addr.s6_addr32[3] ==
631 addr1->v4.sin_addr.s_addr)
632 return 1;
633
634 if (addr2->sa.sa_family == AF_INET &&
635 addr1->sa.sa_family == AF_INET6 &&
636 ipv6_addr_v4mapped(&addr1->v6.sin6_addr) &&
637 addr1->v6.sin6_addr.s6_addr32[3] ==
638 addr2->v4.sin_addr.s_addr)
639 return 1;
640
641 return 0;
642 }
643
644 if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))
645 return 0;
646
647 /* If this is a linklocal address, compare the scope_id. */
648 if ((ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) &&
649 addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&
650 addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)
651 return 0;
652
653 return 1;
654}
655
656/* Compare addresses exactly.
657 * v4-mapped-v6 is also in consideration.
658 */
659static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
660 const union sctp_addr *addr2)
661{
662 return __sctp_v6_cmp_addr(addr1, addr2) &&
663 addr1->v6.sin6_port == addr2->v6.sin6_port;
664}
665
666/* Initialize addr struct to INADDR_ANY. */
667static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port)
668{
669 memset(addr, 0x00, sizeof(union sctp_addr));
670 addr->v6.sin6_family = AF_INET6;
671 addr->v6.sin6_port = port;
672}
673
674/* Is this a wildcard address? */
675static int sctp_v6_is_any(const union sctp_addr *addr)
676{
677 return ipv6_addr_any(&addr->v6.sin6_addr);
678}
679
680/* Should this be available for binding? */
681static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp)
682{
683 const struct in6_addr *in6 = (const struct in6_addr *)&addr->v6.sin6_addr;
684 struct sock *sk = &sp->inet.sk;
685 struct net *net = sock_net(sk);
686 struct net_device *dev = NULL;
687 int type;
688
689 type = ipv6_addr_type(in6);
690 if (IPV6_ADDR_ANY == type)
691 return 1;
692 if (type == IPV6_ADDR_MAPPED) {
693 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
694 return 0;
695 sctp_v6_map_v4(addr);
696 return sctp_get_af_specific(AF_INET)->available(addr, sp);
697 }
698 if (!(type & IPV6_ADDR_UNICAST))
699 return 0;
700
701 if (sk->sk_bound_dev_if) {
702 dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if);
703 if (!dev)
704 return 0;
705 }
706
707 return ipv6_can_nonlocal_bind(net, &sp->inet) ||
708 ipv6_chk_addr(net, in6, dev, 0);
709}
710
711/* This function checks if the address is a valid address to be used for
712 * SCTP.
713 *
714 * Output:
715 * Return 0 - If the address is a non-unicast or an illegal address.
716 * Return 1 - If the address is a unicast.
717 */
718static int sctp_v6_addr_valid(union sctp_addr *addr,
719 struct sctp_sock *sp,
720 const struct sk_buff *skb)
721{
722 int ret = ipv6_addr_type(&addr->v6.sin6_addr);
723
724 /* Support v4-mapped-v6 address. */
725 if (ret == IPV6_ADDR_MAPPED) {
726 /* Note: This routine is used in input, so v4-mapped-v6
727 * are disallowed here when there is no sctp_sock.
728 */
729 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
730 return 0;
731 sctp_v6_map_v4(addr);
732 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb);
733 }
734
735 /* Is this a non-unicast address */
736 if (!(ret & IPV6_ADDR_UNICAST))
737 return 0;
738
739 return 1;
740}
741
742/* What is the scope of 'addr'? */
743static enum sctp_scope sctp_v6_scope(union sctp_addr *addr)
744{
745 enum sctp_scope retval;
746 int v6scope;
747
748 /* The IPv6 scope is really a set of bit fields.
749 * See IFA_* in <net/if_inet6.h>. Map to a generic SCTP scope.
750 */
751
752 v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
753 switch (v6scope) {
754 case IFA_HOST:
755 retval = SCTP_SCOPE_LOOPBACK;
756 break;
757 case IFA_LINK:
758 retval = SCTP_SCOPE_LINK;
759 break;
760 case IFA_SITE:
761 retval = SCTP_SCOPE_PRIVATE;
762 break;
763 default:
764 retval = SCTP_SCOPE_GLOBAL;
765 break;
766 }
767
768 return retval;
769}
770
771/* Create and initialize a new sk for the socket to be returned by accept(). */
772static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
773 struct sctp_association *asoc,
774 bool kern)
775{
776 struct sock *newsk;
777 struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
778 struct sctp6_sock *newsctp6sk;
779
780 newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot, kern);
781 if (!newsk)
782 goto out;
783
784 sock_init_data(NULL, newsk);
785
786 sctp_copy_sock(newsk, sk, asoc);
787 sock_reset_flag(sk, SOCK_ZAPPED);
788
789 newsctp6sk = (struct sctp6_sock *)newsk;
790 inet_sk(newsk)->pinet6 = &newsctp6sk->inet6;
791
792 sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped;
793
794 newnp = inet6_sk(newsk);
795
796 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
797 newnp->ipv6_mc_list = NULL;
798 newnp->ipv6_ac_list = NULL;
799 newnp->ipv6_fl_list = NULL;
800
801 sctp_v6_copy_ip_options(sk, newsk);
802
803 /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
804 * and getpeername().
805 */
806 sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
807
808 newsk->sk_v6_rcv_saddr = sk->sk_v6_rcv_saddr;
809
810 sk_refcnt_debug_inc(newsk);
811
812 if (newsk->sk_prot->init(newsk)) {
813 sk_common_release(newsk);
814 newsk = NULL;
815 }
816
817out:
818 return newsk;
819}
820
821/* Format a sockaddr for return to user space. This makes sure the return is
822 * AF_INET or AF_INET6 depending on the SCTP_I_WANT_MAPPED_V4_ADDR option.
823 */
824static int sctp_v6_addr_to_user(struct sctp_sock *sp, union sctp_addr *addr)
825{
826 if (sp->v4mapped) {
827 if (addr->sa.sa_family == AF_INET)
828 sctp_v4_map_v6(addr);
829 } else {
830 if (addr->sa.sa_family == AF_INET6 &&
831 ipv6_addr_v4mapped(&addr->v6.sin6_addr))
832 sctp_v6_map_v4(addr);
833 }
834
835 if (addr->sa.sa_family == AF_INET) {
836 memset(addr->v4.sin_zero, 0, sizeof(addr->v4.sin_zero));
837 return sizeof(struct sockaddr_in);
838 }
839 return sizeof(struct sockaddr_in6);
840}
841
842/* Where did this skb come from? */
843static int sctp_v6_skb_iif(const struct sk_buff *skb)
844{
845 return inet6_iif(skb);
846}
847
848static int sctp_v6_skb_sdif(const struct sk_buff *skb)
849{
850 return inet6_sdif(skb);
851}
852
853/* Was this packet marked by Explicit Congestion Notification? */
854static int sctp_v6_is_ce(const struct sk_buff *skb)
855{
856 return *((__u32 *)(ipv6_hdr(skb))) & (__force __u32)htonl(1 << 20);
857}
858
859/* Dump the v6 addr to the seq file. */
860static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
861{
862 seq_printf(seq, "%pI6 ", &addr->v6.sin6_addr);
863}
864
865static void sctp_v6_ecn_capable(struct sock *sk)
866{
867 inet6_sk(sk)->tclass |= INET_ECN_ECT_0;
868}
869
870/* Initialize a PF_INET msgname from a ulpevent. */
871static void sctp_inet6_event_msgname(struct sctp_ulpevent *event,
872 char *msgname, int *addrlen)
873{
874 union sctp_addr *addr;
875 struct sctp_association *asoc;
876 union sctp_addr *paddr;
877
878 if (!msgname)
879 return;
880
881 addr = (union sctp_addr *)msgname;
882 asoc = event->asoc;
883 paddr = &asoc->peer.primary_addr;
884
885 if (paddr->sa.sa_family == AF_INET) {
886 addr->v4.sin_family = AF_INET;
887 addr->v4.sin_port = htons(asoc->peer.port);
888 addr->v4.sin_addr = paddr->v4.sin_addr;
889 } else {
890 addr->v6.sin6_family = AF_INET6;
891 addr->v6.sin6_flowinfo = 0;
892 if (ipv6_addr_type(&paddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
893 addr->v6.sin6_scope_id = paddr->v6.sin6_scope_id;
894 else
895 addr->v6.sin6_scope_id = 0;
896 addr->v6.sin6_port = htons(asoc->peer.port);
897 addr->v6.sin6_addr = paddr->v6.sin6_addr;
898 }
899
900 *addrlen = sctp_v6_addr_to_user(sctp_sk(asoc->base.sk), addr);
901}
902
903/* Initialize a msg_name from an inbound skb. */
904static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname,
905 int *addr_len)
906{
907 union sctp_addr *addr;
908 struct sctphdr *sh;
909
910 if (!msgname)
911 return;
912
913 addr = (union sctp_addr *)msgname;
914 sh = sctp_hdr(skb);
915
916 if (ip_hdr(skb)->version == 4) {
917 addr->v4.sin_family = AF_INET;
918 addr->v4.sin_port = sh->source;
919 addr->v4.sin_addr.s_addr = ip_hdr(skb)->saddr;
920 } else {
921 addr->v6.sin6_family = AF_INET6;
922 addr->v6.sin6_flowinfo = 0;
923 addr->v6.sin6_port = sh->source;
924 addr->v6.sin6_addr = ipv6_hdr(skb)->saddr;
925 if (ipv6_addr_type(&addr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
926 addr->v6.sin6_scope_id = sctp_v6_skb_iif(skb);
927 else
928 addr->v6.sin6_scope_id = 0;
929 }
930
931 *addr_len = sctp_v6_addr_to_user(sctp_sk(skb->sk), addr);
932}
933
934/* Do we support this AF? */
935static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp)
936{
937 switch (family) {
938 case AF_INET6:
939 return 1;
940 /* v4-mapped-v6 addresses */
941 case AF_INET:
942 if (!ipv6_only_sock(sctp_opt2sk(sp)))
943 return 1;
944 fallthrough;
945 default:
946 return 0;
947 }
948}
949
950/* Address matching with wildcards allowed. This extra level
951 * of indirection lets us choose whether a PF_INET6 should
952 * disallow any v4 addresses if we so choose.
953 */
954static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
955 const union sctp_addr *addr2,
956 struct sctp_sock *opt)
957{
958 struct sock *sk = sctp_opt2sk(opt);
959 struct sctp_af *af1, *af2;
960
961 af1 = sctp_get_af_specific(addr1->sa.sa_family);
962 af2 = sctp_get_af_specific(addr2->sa.sa_family);
963
964 if (!af1 || !af2)
965 return 0;
966
967 /* If the socket is IPv6 only, v4 addrs will not match */
968 if (ipv6_only_sock(sk) && af1 != af2)
969 return 0;
970
971 /* Today, wildcard AF_INET/AF_INET6. */
972 if (sctp_is_any(sk, addr1) || sctp_is_any(sk, addr2))
973 return 1;
974
975 if (addr1->sa.sa_family == AF_INET && addr2->sa.sa_family == AF_INET)
976 return addr1->v4.sin_addr.s_addr == addr2->v4.sin_addr.s_addr;
977
978 return __sctp_v6_cmp_addr(addr1, addr2);
979}
980
981/* Verify that the provided sockaddr looks bindable. Common verification,
982 * has already been taken care of.
983 */
984static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
985{
986 struct sctp_af *af;
987
988 /* ASSERT: address family has already been verified. */
989 if (addr->sa.sa_family != AF_INET6)
990 af = sctp_get_af_specific(addr->sa.sa_family);
991 else {
992 int type = ipv6_addr_type(&addr->v6.sin6_addr);
993 struct net_device *dev;
994
995 if (type & IPV6_ADDR_LINKLOCAL) {
996 struct net *net;
997 if (!addr->v6.sin6_scope_id)
998 return 0;
999 net = sock_net(&opt->inet.sk);
1000 rcu_read_lock();
1001 dev = dev_get_by_index_rcu(net, addr->v6.sin6_scope_id);
1002 if (!dev || !(ipv6_can_nonlocal_bind(net, &opt->inet) ||
1003 ipv6_chk_addr(net, &addr->v6.sin6_addr,
1004 dev, 0))) {
1005 rcu_read_unlock();
1006 return 0;
1007 }
1008 rcu_read_unlock();
1009 }
1010
1011 af = opt->pf->af;
1012 }
1013 return af->available(addr, opt);
1014}
1015
1016/* Verify that the provided sockaddr looks sendable. Common verification,
1017 * has already been taken care of.
1018 */
1019static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
1020{
1021 struct sctp_af *af = NULL;
1022
1023 /* ASSERT: address family has already been verified. */
1024 if (addr->sa.sa_family != AF_INET6)
1025 af = sctp_get_af_specific(addr->sa.sa_family);
1026 else {
1027 int type = ipv6_addr_type(&addr->v6.sin6_addr);
1028 struct net_device *dev;
1029
1030 if (type & IPV6_ADDR_LINKLOCAL) {
1031 if (!addr->v6.sin6_scope_id)
1032 return 0;
1033 rcu_read_lock();
1034 dev = dev_get_by_index_rcu(sock_net(&opt->inet.sk),
1035 addr->v6.sin6_scope_id);
1036 rcu_read_unlock();
1037 if (!dev)
1038 return 0;
1039 }
1040 af = opt->pf->af;
1041 }
1042
1043 return af != NULL;
1044}
1045
1046/* Fill in Supported Address Type information for INIT and INIT-ACK
1047 * chunks. Note: In the future, we may want to look at sock options
1048 * to determine whether a PF_INET6 socket really wants to have IPV4
1049 * addresses.
1050 * Returns number of addresses supported.
1051 */
1052static int sctp_inet6_supported_addrs(const struct sctp_sock *opt,
1053 __be16 *types)
1054{
1055 types[0] = SCTP_PARAM_IPV6_ADDRESS;
1056 if (!opt || !ipv6_only_sock(sctp_opt2sk(opt))) {
1057 types[1] = SCTP_PARAM_IPV4_ADDRESS;
1058 return 2;
1059 }
1060 return 1;
1061}
1062
1063/* Handle SCTP_I_WANT_MAPPED_V4_ADDR for getpeername() and getsockname() */
1064static int sctp_getname(struct socket *sock, struct sockaddr *uaddr,
1065 int peer)
1066{
1067 int rc;
1068
1069 rc = inet6_getname(sock, uaddr, peer);
1070
1071 if (rc < 0)
1072 return rc;
1073
1074 rc = sctp_v6_addr_to_user(sctp_sk(sock->sk),
1075 (union sctp_addr *)uaddr);
1076
1077 return rc;
1078}
1079
1080static const struct proto_ops inet6_seqpacket_ops = {
1081 .family = PF_INET6,
1082 .owner = THIS_MODULE,
1083 .release = inet6_release,
1084 .bind = inet6_bind,
1085 .connect = sctp_inet_connect,
1086 .socketpair = sock_no_socketpair,
1087 .accept = inet_accept,
1088 .getname = sctp_getname,
1089 .poll = sctp_poll,
1090 .ioctl = inet6_ioctl,
1091 .gettstamp = sock_gettstamp,
1092 .listen = sctp_inet_listen,
1093 .shutdown = inet_shutdown,
1094 .setsockopt = sock_common_setsockopt,
1095 .getsockopt = sock_common_getsockopt,
1096 .sendmsg = inet_sendmsg,
1097 .recvmsg = inet_recvmsg,
1098 .mmap = sock_no_mmap,
1099#ifdef CONFIG_COMPAT
1100 .compat_ioctl = inet6_compat_ioctl,
1101#endif
1102};
1103
1104static struct inet_protosw sctpv6_seqpacket_protosw = {
1105 .type = SOCK_SEQPACKET,
1106 .protocol = IPPROTO_SCTP,
1107 .prot = &sctpv6_prot,
1108 .ops = &inet6_seqpacket_ops,
1109 .flags = SCTP_PROTOSW_FLAG
1110};
1111static struct inet_protosw sctpv6_stream_protosw = {
1112 .type = SOCK_STREAM,
1113 .protocol = IPPROTO_SCTP,
1114 .prot = &sctpv6_prot,
1115 .ops = &inet6_seqpacket_ops,
1116 .flags = SCTP_PROTOSW_FLAG,
1117};
1118
1119static int sctp6_rcv(struct sk_buff *skb)
1120{
1121 SCTP_INPUT_CB(skb)->encap_port = 0;
1122 return sctp_rcv(skb) ? -1 : 0;
1123}
1124
1125static const struct inet6_protocol sctpv6_protocol = {
1126 .handler = sctp6_rcv,
1127 .err_handler = sctp_v6_err,
1128 .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
1129};
1130
1131static struct sctp_af sctp_af_inet6 = {
1132 .sa_family = AF_INET6,
1133 .sctp_xmit = sctp_v6_xmit,
1134 .setsockopt = ipv6_setsockopt,
1135 .getsockopt = ipv6_getsockopt,
1136 .get_dst = sctp_v6_get_dst,
1137 .get_saddr = sctp_v6_get_saddr,
1138 .copy_addrlist = sctp_v6_copy_addrlist,
1139 .from_skb = sctp_v6_from_skb,
1140 .from_sk = sctp_v6_from_sk,
1141 .from_addr_param = sctp_v6_from_addr_param,
1142 .to_addr_param = sctp_v6_to_addr_param,
1143 .cmp_addr = sctp_v6_cmp_addr,
1144 .scope = sctp_v6_scope,
1145 .addr_valid = sctp_v6_addr_valid,
1146 .inaddr_any = sctp_v6_inaddr_any,
1147 .is_any = sctp_v6_is_any,
1148 .available = sctp_v6_available,
1149 .skb_iif = sctp_v6_skb_iif,
1150 .skb_sdif = sctp_v6_skb_sdif,
1151 .is_ce = sctp_v6_is_ce,
1152 .seq_dump_addr = sctp_v6_seq_dump_addr,
1153 .ecn_capable = sctp_v6_ecn_capable,
1154 .net_header_len = sizeof(struct ipv6hdr),
1155 .sockaddr_len = sizeof(struct sockaddr_in6),
1156 .ip_options_len = sctp_v6_ip_options_len,
1157};
1158
1159static struct sctp_pf sctp_pf_inet6 = {
1160 .event_msgname = sctp_inet6_event_msgname,
1161 .skb_msgname = sctp_inet6_skb_msgname,
1162 .af_supported = sctp_inet6_af_supported,
1163 .cmp_addr = sctp_inet6_cmp_addr,
1164 .bind_verify = sctp_inet6_bind_verify,
1165 .send_verify = sctp_inet6_send_verify,
1166 .supported_addrs = sctp_inet6_supported_addrs,
1167 .create_accept_sk = sctp_v6_create_accept_sk,
1168 .addr_to_user = sctp_v6_addr_to_user,
1169 .to_sk_saddr = sctp_v6_to_sk_saddr,
1170 .to_sk_daddr = sctp_v6_to_sk_daddr,
1171 .copy_ip_options = sctp_v6_copy_ip_options,
1172 .af = &sctp_af_inet6,
1173};
1174
1175/* Initialize IPv6 support and register with socket layer. */
1176void sctp_v6_pf_init(void)
1177{
1178 /* Register the SCTP specific PF_INET6 functions. */
1179 sctp_register_pf(&sctp_pf_inet6, PF_INET6);
1180
1181 /* Register the SCTP specific AF_INET6 functions. */
1182 sctp_register_af(&sctp_af_inet6);
1183}
1184
1185void sctp_v6_pf_exit(void)
1186{
1187 list_del(&sctp_af_inet6.list);
1188}
1189
1190/* Initialize IPv6 support and register with socket layer. */
1191int sctp_v6_protosw_init(void)
1192{
1193 int rc;
1194
1195 rc = proto_register(&sctpv6_prot, 1);
1196 if (rc)
1197 return rc;
1198
1199 /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
1200 inet6_register_protosw(&sctpv6_seqpacket_protosw);
1201 inet6_register_protosw(&sctpv6_stream_protosw);
1202
1203 return 0;
1204}
1205
1206void sctp_v6_protosw_exit(void)
1207{
1208 inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
1209 inet6_unregister_protosw(&sctpv6_stream_protosw);
1210 proto_unregister(&sctpv6_prot);
1211}
1212
1213
1214/* Register with inet6 layer. */
1215int sctp_v6_add_protocol(void)
1216{
1217 /* Register notifier for inet6 address additions/deletions. */
1218 register_inet6addr_notifier(&sctp_inet6addr_notifier);
1219
1220 if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
1221 return -EAGAIN;
1222
1223 return 0;
1224}
1225
1226/* Unregister with inet6 layer. */
1227void sctp_v6_del_protocol(void)
1228{
1229 inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
1230 unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
1231}