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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 <asm/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_BH(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, asoc);
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
213 pr_debug("%s: skb:%p, len:%d, src:%pI6 dst:%pI6\n", __func__, skb,
214 skb->len, &fl6->saddr, &fl6->daddr);
215
216 IP6_ECN_flow_xmit(sk, fl6->flowlabel);
217
218 if (!(transport->param_flags & SPP_PMTUD_ENABLE))
219 skb->local_df = 1;
220
221 SCTP_INC_STATS(sock_net(sk), SCTP_MIB_OUTSCTPPACKS);
222
223 return ip6_xmit(sk, skb, fl6, np->opt, np->tclass);
224}
225
226/* Returns the dst cache entry for the given source and destination ip
227 * addresses.
228 */
229static void sctp_v6_get_dst(struct sctp_transport *t, union sctp_addr *saddr,
230 struct flowi *fl, struct sock *sk)
231{
232 struct sctp_association *asoc = t->asoc;
233 struct dst_entry *dst = NULL;
234 struct flowi6 *fl6 = &fl->u.ip6;
235 struct sctp_bind_addr *bp;
236 struct ipv6_pinfo *np = inet6_sk(sk);
237 struct sctp_sockaddr_entry *laddr;
238 union sctp_addr *baddr = NULL;
239 union sctp_addr *daddr = &t->ipaddr;
240 union sctp_addr dst_saddr;
241 struct in6_addr *final_p, final;
242 __u8 matchlen = 0;
243 __u8 bmatchlen;
244 sctp_scope_t scope;
245
246 memset(fl6, 0, sizeof(struct flowi6));
247 fl6->daddr = daddr->v6.sin6_addr;
248 fl6->fl6_dport = daddr->v6.sin6_port;
249 fl6->flowi6_proto = IPPROTO_SCTP;
250 if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
251 fl6->flowi6_oif = daddr->v6.sin6_scope_id;
252
253 pr_debug("%s: dst=%pI6 ", __func__, &fl6->daddr);
254
255 if (asoc)
256 fl6->fl6_sport = htons(asoc->base.bind_addr.port);
257
258 if (saddr) {
259 fl6->saddr = saddr->v6.sin6_addr;
260 fl6->fl6_sport = saddr->v6.sin6_port;
261
262 pr_debug("src=%pI6 - ", &fl6->saddr);
263 }
264
265 final_p = fl6_update_dst(fl6, np->opt, &final);
266 dst = ip6_dst_lookup_flow(sk, fl6, final_p);
267 if (!asoc || saddr)
268 goto out;
269
270 bp = &asoc->base.bind_addr;
271 scope = sctp_scope(daddr);
272 /* ip6_dst_lookup has filled in the fl6->saddr for us. Check
273 * to see if we can use it.
274 */
275 if (!IS_ERR(dst)) {
276 /* Walk through the bind address list and look for a bind
277 * address that matches the source address of the returned dst.
278 */
279 sctp_v6_to_addr(&dst_saddr, &fl6->saddr, htons(bp->port));
280 rcu_read_lock();
281 list_for_each_entry_rcu(laddr, &bp->address_list, list) {
282 if (!laddr->valid || laddr->state == SCTP_ADDR_DEL ||
283 (laddr->state != SCTP_ADDR_SRC &&
284 !asoc->src_out_of_asoc_ok))
285 continue;
286
287 /* Do not compare against v4 addrs */
288 if ((laddr->a.sa.sa_family == AF_INET6) &&
289 (sctp_v6_cmp_addr(&dst_saddr, &laddr->a))) {
290 rcu_read_unlock();
291 goto out;
292 }
293 }
294 rcu_read_unlock();
295 /* None of the bound addresses match the source address of the
296 * dst. So release it.
297 */
298 dst_release(dst);
299 dst = NULL;
300 }
301
302 /* Walk through the bind address list and try to get the
303 * best source address for a given destination.
304 */
305 rcu_read_lock();
306 list_for_each_entry_rcu(laddr, &bp->address_list, list) {
307 if (!laddr->valid)
308 continue;
309 if ((laddr->state == SCTP_ADDR_SRC) &&
310 (laddr->a.sa.sa_family == AF_INET6) &&
311 (scope <= sctp_scope(&laddr->a))) {
312 bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a);
313 if (!baddr || (matchlen < bmatchlen)) {
314 baddr = &laddr->a;
315 matchlen = bmatchlen;
316 }
317 }
318 }
319 rcu_read_unlock();
320
321 if (baddr) {
322 fl6->saddr = baddr->v6.sin6_addr;
323 fl6->fl6_sport = baddr->v6.sin6_port;
324 final_p = fl6_update_dst(fl6, np->opt, &final);
325 dst = ip6_dst_lookup_flow(sk, fl6, final_p);
326 }
327
328out:
329 if (!IS_ERR_OR_NULL(dst)) {
330 struct rt6_info *rt;
331
332 rt = (struct rt6_info *)dst;
333 t->dst = dst;
334 t->dst_cookie = rt->rt6i_node ? rt->rt6i_node->fn_sernum : 0;
335 pr_debug("rt6_dst:%pI6 rt6_src:%pI6\n", &rt->rt6i_dst.addr,
336 &fl6->saddr);
337 } else {
338 t->dst = NULL;
339
340 pr_debug("no route\n");
341 }
342}
343
344/* Returns the number of consecutive initial bits that match in the 2 ipv6
345 * addresses.
346 */
347static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
348 union sctp_addr *s2)
349{
350 return ipv6_addr_diff(&s1->v6.sin6_addr, &s2->v6.sin6_addr);
351}
352
353/* Fills in the source address(saddr) based on the destination address(daddr)
354 * and asoc's bind address list.
355 */
356static void sctp_v6_get_saddr(struct sctp_sock *sk,
357 struct sctp_transport *t,
358 struct flowi *fl)
359{
360 struct flowi6 *fl6 = &fl->u.ip6;
361 union sctp_addr *saddr = &t->saddr;
362
363 pr_debug("%s: asoc:%p dst:%p\n", __func__, t->asoc, t->dst);
364
365 if (t->dst) {
366 saddr->v6.sin6_family = AF_INET6;
367 saddr->v6.sin6_addr = fl6->saddr;
368 }
369}
370
371/* Make a copy of all potential local addresses. */
372static void sctp_v6_copy_addrlist(struct list_head *addrlist,
373 struct net_device *dev)
374{
375 struct inet6_dev *in6_dev;
376 struct inet6_ifaddr *ifp;
377 struct sctp_sockaddr_entry *addr;
378
379 rcu_read_lock();
380 if ((in6_dev = __in6_dev_get(dev)) == NULL) {
381 rcu_read_unlock();
382 return;
383 }
384
385 read_lock_bh(&in6_dev->lock);
386 list_for_each_entry(ifp, &in6_dev->addr_list, if_list) {
387 /* Add the address to the local list. */
388 addr = kzalloc(sizeof(*addr), GFP_ATOMIC);
389 if (addr) {
390 addr->a.v6.sin6_family = AF_INET6;
391 addr->a.v6.sin6_port = 0;
392 addr->a.v6.sin6_addr = ifp->addr;
393 addr->a.v6.sin6_scope_id = dev->ifindex;
394 addr->valid = 1;
395 INIT_LIST_HEAD(&addr->list);
396 list_add_tail(&addr->list, addrlist);
397 }
398 }
399
400 read_unlock_bh(&in6_dev->lock);
401 rcu_read_unlock();
402}
403
404/* Initialize a sockaddr_storage from in incoming skb. */
405static void sctp_v6_from_skb(union sctp_addr *addr, struct sk_buff *skb,
406 int is_saddr)
407{
408 __be16 *port;
409 struct sctphdr *sh;
410
411 port = &addr->v6.sin6_port;
412 addr->v6.sin6_family = AF_INET6;
413 addr->v6.sin6_flowinfo = 0; /* FIXME */
414 addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif;
415
416 sh = sctp_hdr(skb);
417 if (is_saddr) {
418 *port = sh->source;
419 addr->v6.sin6_addr = ipv6_hdr(skb)->saddr;
420 } else {
421 *port = sh->dest;
422 addr->v6.sin6_addr = ipv6_hdr(skb)->daddr;
423 }
424}
425
426/* Initialize an sctp_addr from a socket. */
427static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk)
428{
429 addr->v6.sin6_family = AF_INET6;
430 addr->v6.sin6_port = 0;
431 addr->v6.sin6_addr = sk->sk_v6_rcv_saddr;
432}
433
434/* Initialize sk->sk_rcv_saddr from sctp_addr. */
435static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
436{
437 if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
438 sk->sk_v6_rcv_saddr.s6_addr32[0] = 0;
439 sk->sk_v6_rcv_saddr.s6_addr32[1] = 0;
440 sk->sk_v6_rcv_saddr.s6_addr32[2] = htonl(0x0000ffff);
441 sk->sk_v6_rcv_saddr.s6_addr32[3] =
442 addr->v4.sin_addr.s_addr;
443 } else {
444 sk->sk_v6_rcv_saddr = addr->v6.sin6_addr;
445 }
446}
447
448/* Initialize sk->sk_daddr from sctp_addr. */
449static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
450{
451 if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
452 sk->sk_v6_daddr.s6_addr32[0] = 0;
453 sk->sk_v6_daddr.s6_addr32[1] = 0;
454 sk->sk_v6_daddr.s6_addr32[2] = htonl(0x0000ffff);
455 sk->sk_v6_daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
456 } else {
457 sk->sk_v6_daddr = addr->v6.sin6_addr;
458 }
459}
460
461/* Initialize a sctp_addr from an address parameter. */
462static void sctp_v6_from_addr_param(union sctp_addr *addr,
463 union sctp_addr_param *param,
464 __be16 port, int iif)
465{
466 addr->v6.sin6_family = AF_INET6;
467 addr->v6.sin6_port = port;
468 addr->v6.sin6_flowinfo = 0; /* BUG */
469 addr->v6.sin6_addr = param->v6.addr;
470 addr->v6.sin6_scope_id = iif;
471}
472
473/* Initialize an address parameter from a sctp_addr and return the length
474 * of the address parameter.
475 */
476static int sctp_v6_to_addr_param(const union sctp_addr *addr,
477 union sctp_addr_param *param)
478{
479 int length = sizeof(sctp_ipv6addr_param_t);
480
481 param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS;
482 param->v6.param_hdr.length = htons(length);
483 param->v6.addr = addr->v6.sin6_addr;
484
485 return length;
486}
487
488/* Initialize a sctp_addr from struct in6_addr. */
489static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr,
490 __be16 port)
491{
492 addr->sa.sa_family = AF_INET6;
493 addr->v6.sin6_port = port;
494 addr->v6.sin6_addr = *saddr;
495}
496
497/* Compare addresses exactly.
498 * v4-mapped-v6 is also in consideration.
499 */
500static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
501 const union sctp_addr *addr2)
502{
503 if (addr1->sa.sa_family != addr2->sa.sa_family) {
504 if (addr1->sa.sa_family == AF_INET &&
505 addr2->sa.sa_family == AF_INET6 &&
506 ipv6_addr_v4mapped(&addr2->v6.sin6_addr)) {
507 if (addr2->v6.sin6_port == addr1->v4.sin_port &&
508 addr2->v6.sin6_addr.s6_addr32[3] ==
509 addr1->v4.sin_addr.s_addr)
510 return 1;
511 }
512 if (addr2->sa.sa_family == AF_INET &&
513 addr1->sa.sa_family == AF_INET6 &&
514 ipv6_addr_v4mapped(&addr1->v6.sin6_addr)) {
515 if (addr1->v6.sin6_port == addr2->v4.sin_port &&
516 addr1->v6.sin6_addr.s6_addr32[3] ==
517 addr2->v4.sin_addr.s_addr)
518 return 1;
519 }
520 return 0;
521 }
522 if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))
523 return 0;
524 /* If this is a linklocal address, compare the scope_id. */
525 if (ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) {
526 if (addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&
527 (addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)) {
528 return 0;
529 }
530 }
531
532 return 1;
533}
534
535/* Initialize addr struct to INADDR_ANY. */
536static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port)
537{
538 memset(addr, 0x00, sizeof(union sctp_addr));
539 addr->v6.sin6_family = AF_INET6;
540 addr->v6.sin6_port = port;
541}
542
543/* Is this a wildcard address? */
544static int sctp_v6_is_any(const union sctp_addr *addr)
545{
546 return ipv6_addr_any(&addr->v6.sin6_addr);
547}
548
549/* Should this be available for binding? */
550static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp)
551{
552 int type;
553 const struct in6_addr *in6 = (const struct in6_addr *)&addr->v6.sin6_addr;
554
555 type = ipv6_addr_type(in6);
556 if (IPV6_ADDR_ANY == type)
557 return 1;
558 if (type == IPV6_ADDR_MAPPED) {
559 if (sp && !sp->v4mapped)
560 return 0;
561 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
562 return 0;
563 sctp_v6_map_v4(addr);
564 return sctp_get_af_specific(AF_INET)->available(addr, sp);
565 }
566 if (!(type & IPV6_ADDR_UNICAST))
567 return 0;
568
569 return ipv6_chk_addr(sock_net(&sp->inet.sk), in6, NULL, 0);
570}
571
572/* This function checks if the address is a valid address to be used for
573 * SCTP.
574 *
575 * Output:
576 * Return 0 - If the address is a non-unicast or an illegal address.
577 * Return 1 - If the address is a unicast.
578 */
579static int sctp_v6_addr_valid(union sctp_addr *addr,
580 struct sctp_sock *sp,
581 const struct sk_buff *skb)
582{
583 int ret = ipv6_addr_type(&addr->v6.sin6_addr);
584
585 /* Support v4-mapped-v6 address. */
586 if (ret == IPV6_ADDR_MAPPED) {
587 /* Note: This routine is used in input, so v4-mapped-v6
588 * are disallowed here when there is no sctp_sock.
589 */
590 if (!sp || !sp->v4mapped)
591 return 0;
592 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
593 return 0;
594 sctp_v6_map_v4(addr);
595 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb);
596 }
597
598 /* Is this a non-unicast address */
599 if (!(ret & IPV6_ADDR_UNICAST))
600 return 0;
601
602 return 1;
603}
604
605/* What is the scope of 'addr'? */
606static sctp_scope_t sctp_v6_scope(union sctp_addr *addr)
607{
608 int v6scope;
609 sctp_scope_t retval;
610
611 /* The IPv6 scope is really a set of bit fields.
612 * See IFA_* in <net/if_inet6.h>. Map to a generic SCTP scope.
613 */
614
615 v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
616 switch (v6scope) {
617 case IFA_HOST:
618 retval = SCTP_SCOPE_LOOPBACK;
619 break;
620 case IFA_LINK:
621 retval = SCTP_SCOPE_LINK;
622 break;
623 case IFA_SITE:
624 retval = SCTP_SCOPE_PRIVATE;
625 break;
626 default:
627 retval = SCTP_SCOPE_GLOBAL;
628 break;
629 }
630
631 return retval;
632}
633
634/* Create and initialize a new sk for the socket to be returned by accept(). */
635static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
636 struct sctp_association *asoc)
637{
638 struct sock *newsk;
639 struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
640 struct sctp6_sock *newsctp6sk;
641
642 newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot);
643 if (!newsk)
644 goto out;
645
646 sock_init_data(NULL, newsk);
647
648 sctp_copy_sock(newsk, sk, asoc);
649 sock_reset_flag(sk, SOCK_ZAPPED);
650
651 newsctp6sk = (struct sctp6_sock *)newsk;
652 inet_sk(newsk)->pinet6 = &newsctp6sk->inet6;
653
654 sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped;
655
656 newnp = inet6_sk(newsk);
657
658 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
659
660 /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
661 * and getpeername().
662 */
663 sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
664
665 newsk->sk_v6_rcv_saddr = sk->sk_v6_rcv_saddr;
666
667 sk_refcnt_debug_inc(newsk);
668
669 if (newsk->sk_prot->init(newsk)) {
670 sk_common_release(newsk);
671 newsk = NULL;
672 }
673
674out:
675 return newsk;
676}
677
678/* Map v4 address to mapped v6 address */
679static void sctp_v6_addr_v4map(struct sctp_sock *sp, union sctp_addr *addr)
680{
681 if (sp->v4mapped && AF_INET == addr->sa.sa_family)
682 sctp_v4_map_v6(addr);
683}
684
685/* Where did this skb come from? */
686static int sctp_v6_skb_iif(const struct sk_buff *skb)
687{
688 struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb;
689 return opt->iif;
690}
691
692/* Was this packet marked by Explicit Congestion Notification? */
693static int sctp_v6_is_ce(const struct sk_buff *skb)
694{
695 return *((__u32 *)(ipv6_hdr(skb))) & htonl(1 << 20);
696}
697
698/* Dump the v6 addr to the seq file. */
699static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
700{
701 seq_printf(seq, "%pI6 ", &addr->v6.sin6_addr);
702}
703
704static void sctp_v6_ecn_capable(struct sock *sk)
705{
706 inet6_sk(sk)->tclass |= INET_ECN_ECT_0;
707}
708
709/* Initialize a PF_INET6 socket msg_name. */
710static void sctp_inet6_msgname(char *msgname, int *addr_len)
711{
712 struct sockaddr_in6 *sin6;
713
714 sin6 = (struct sockaddr_in6 *)msgname;
715 sin6->sin6_family = AF_INET6;
716 sin6->sin6_flowinfo = 0;
717 sin6->sin6_scope_id = 0; /*FIXME */
718 *addr_len = sizeof(struct sockaddr_in6);
719}
720
721/* Initialize a PF_INET msgname from a ulpevent. */
722static void sctp_inet6_event_msgname(struct sctp_ulpevent *event,
723 char *msgname, int *addrlen)
724{
725 struct sockaddr_in6 *sin6, *sin6from;
726
727 if (msgname) {
728 union sctp_addr *addr;
729 struct sctp_association *asoc;
730
731 asoc = event->asoc;
732 sctp_inet6_msgname(msgname, addrlen);
733 sin6 = (struct sockaddr_in6 *)msgname;
734 sin6->sin6_port = htons(asoc->peer.port);
735 addr = &asoc->peer.primary_addr;
736
737 /* Note: If we go to a common v6 format, this code
738 * will change.
739 */
740
741 /* Map ipv4 address into v4-mapped-on-v6 address. */
742 if (sctp_sk(asoc->base.sk)->v4mapped &&
743 AF_INET == addr->sa.sa_family) {
744 sctp_v4_map_v6((union sctp_addr *)sin6);
745 sin6->sin6_addr.s6_addr32[3] =
746 addr->v4.sin_addr.s_addr;
747 return;
748 }
749
750 sin6from = &asoc->peer.primary_addr.v6;
751 sin6->sin6_addr = sin6from->sin6_addr;
752 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
753 sin6->sin6_scope_id = sin6from->sin6_scope_id;
754 }
755}
756
757/* Initialize a msg_name from an inbound skb. */
758static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname,
759 int *addr_len)
760{
761 struct sctphdr *sh;
762 struct sockaddr_in6 *sin6;
763
764 if (msgname) {
765 sctp_inet6_msgname(msgname, addr_len);
766 sin6 = (struct sockaddr_in6 *)msgname;
767 sh = sctp_hdr(skb);
768 sin6->sin6_port = sh->source;
769
770 /* Map ipv4 address into v4-mapped-on-v6 address. */
771 if (sctp_sk(skb->sk)->v4mapped &&
772 ip_hdr(skb)->version == 4) {
773 sctp_v4_map_v6((union sctp_addr *)sin6);
774 sin6->sin6_addr.s6_addr32[3] = ip_hdr(skb)->saddr;
775 return;
776 }
777
778 /* Otherwise, just copy the v6 address. */
779 sin6->sin6_addr = ipv6_hdr(skb)->saddr;
780 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) {
781 struct sctp_ulpevent *ev = sctp_skb2event(skb);
782 sin6->sin6_scope_id = ev->iif;
783 }
784 }
785}
786
787/* Do we support this AF? */
788static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp)
789{
790 switch (family) {
791 case AF_INET6:
792 return 1;
793 /* v4-mapped-v6 addresses */
794 case AF_INET:
795 if (!__ipv6_only_sock(sctp_opt2sk(sp)))
796 return 1;
797 default:
798 return 0;
799 }
800}
801
802/* Address matching with wildcards allowed. This extra level
803 * of indirection lets us choose whether a PF_INET6 should
804 * disallow any v4 addresses if we so choose.
805 */
806static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
807 const union sctp_addr *addr2,
808 struct sctp_sock *opt)
809{
810 struct sctp_af *af1, *af2;
811 struct sock *sk = sctp_opt2sk(opt);
812
813 af1 = sctp_get_af_specific(addr1->sa.sa_family);
814 af2 = sctp_get_af_specific(addr2->sa.sa_family);
815
816 if (!af1 || !af2)
817 return 0;
818
819 /* If the socket is IPv6 only, v4 addrs will not match */
820 if (__ipv6_only_sock(sk) && af1 != af2)
821 return 0;
822
823 /* Today, wildcard AF_INET/AF_INET6. */
824 if (sctp_is_any(sk, addr1) || sctp_is_any(sk, addr2))
825 return 1;
826
827 if (addr1->sa.sa_family != addr2->sa.sa_family)
828 return 0;
829
830 return af1->cmp_addr(addr1, addr2);
831}
832
833/* Verify that the provided sockaddr looks bindable. Common verification,
834 * has already been taken care of.
835 */
836static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
837{
838 struct sctp_af *af;
839
840 /* ASSERT: address family has already been verified. */
841 if (addr->sa.sa_family != AF_INET6)
842 af = sctp_get_af_specific(addr->sa.sa_family);
843 else {
844 int type = ipv6_addr_type(&addr->v6.sin6_addr);
845 struct net_device *dev;
846
847 if (type & IPV6_ADDR_LINKLOCAL) {
848 struct net *net;
849 if (!addr->v6.sin6_scope_id)
850 return 0;
851 net = sock_net(&opt->inet.sk);
852 rcu_read_lock();
853 dev = dev_get_by_index_rcu(net, addr->v6.sin6_scope_id);
854 if (!dev ||
855 !ipv6_chk_addr(net, &addr->v6.sin6_addr, dev, 0)) {
856 rcu_read_unlock();
857 return 0;
858 }
859 rcu_read_unlock();
860 } else if (type == IPV6_ADDR_MAPPED) {
861 if (!opt->v4mapped)
862 return 0;
863 }
864
865 af = opt->pf->af;
866 }
867 return af->available(addr, opt);
868}
869
870/* Verify that the provided sockaddr looks sendable. Common verification,
871 * has already been taken care of.
872 */
873static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
874{
875 struct sctp_af *af = NULL;
876
877 /* ASSERT: address family has already been verified. */
878 if (addr->sa.sa_family != AF_INET6)
879 af = sctp_get_af_specific(addr->sa.sa_family);
880 else {
881 int type = ipv6_addr_type(&addr->v6.sin6_addr);
882 struct net_device *dev;
883
884 if (type & IPV6_ADDR_LINKLOCAL) {
885 if (!addr->v6.sin6_scope_id)
886 return 0;
887 rcu_read_lock();
888 dev = dev_get_by_index_rcu(sock_net(&opt->inet.sk),
889 addr->v6.sin6_scope_id);
890 rcu_read_unlock();
891 if (!dev)
892 return 0;
893 }
894 af = opt->pf->af;
895 }
896
897 return af != NULL;
898}
899
900/* Fill in Supported Address Type information for INIT and INIT-ACK
901 * chunks. Note: In the future, we may want to look at sock options
902 * to determine whether a PF_INET6 socket really wants to have IPV4
903 * addresses.
904 * Returns number of addresses supported.
905 */
906static int sctp_inet6_supported_addrs(const struct sctp_sock *opt,
907 __be16 *types)
908{
909 types[0] = SCTP_PARAM_IPV6_ADDRESS;
910 if (!opt || !ipv6_only_sock(sctp_opt2sk(opt))) {
911 types[1] = SCTP_PARAM_IPV4_ADDRESS;
912 return 2;
913 }
914 return 1;
915}
916
917static const struct proto_ops inet6_seqpacket_ops = {
918 .family = PF_INET6,
919 .owner = THIS_MODULE,
920 .release = inet6_release,
921 .bind = inet6_bind,
922 .connect = inet_dgram_connect,
923 .socketpair = sock_no_socketpair,
924 .accept = inet_accept,
925 .getname = inet6_getname,
926 .poll = sctp_poll,
927 .ioctl = inet6_ioctl,
928 .listen = sctp_inet_listen,
929 .shutdown = inet_shutdown,
930 .setsockopt = sock_common_setsockopt,
931 .getsockopt = sock_common_getsockopt,
932 .sendmsg = inet_sendmsg,
933 .recvmsg = sock_common_recvmsg,
934 .mmap = sock_no_mmap,
935#ifdef CONFIG_COMPAT
936 .compat_setsockopt = compat_sock_common_setsockopt,
937 .compat_getsockopt = compat_sock_common_getsockopt,
938#endif
939};
940
941static struct inet_protosw sctpv6_seqpacket_protosw = {
942 .type = SOCK_SEQPACKET,
943 .protocol = IPPROTO_SCTP,
944 .prot = &sctpv6_prot,
945 .ops = &inet6_seqpacket_ops,
946 .no_check = 0,
947 .flags = SCTP_PROTOSW_FLAG
948};
949static struct inet_protosw sctpv6_stream_protosw = {
950 .type = SOCK_STREAM,
951 .protocol = IPPROTO_SCTP,
952 .prot = &sctpv6_prot,
953 .ops = &inet6_seqpacket_ops,
954 .no_check = 0,
955 .flags = SCTP_PROTOSW_FLAG,
956};
957
958static int sctp6_rcv(struct sk_buff *skb)
959{
960 return sctp_rcv(skb) ? -1 : 0;
961}
962
963static const struct inet6_protocol sctpv6_protocol = {
964 .handler = sctp6_rcv,
965 .err_handler = sctp_v6_err,
966 .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
967};
968
969static struct sctp_af sctp_af_inet6 = {
970 .sa_family = AF_INET6,
971 .sctp_xmit = sctp_v6_xmit,
972 .setsockopt = ipv6_setsockopt,
973 .getsockopt = ipv6_getsockopt,
974 .get_dst = sctp_v6_get_dst,
975 .get_saddr = sctp_v6_get_saddr,
976 .copy_addrlist = sctp_v6_copy_addrlist,
977 .from_skb = sctp_v6_from_skb,
978 .from_sk = sctp_v6_from_sk,
979 .to_sk_saddr = sctp_v6_to_sk_saddr,
980 .to_sk_daddr = sctp_v6_to_sk_daddr,
981 .from_addr_param = sctp_v6_from_addr_param,
982 .to_addr_param = sctp_v6_to_addr_param,
983 .cmp_addr = sctp_v6_cmp_addr,
984 .scope = sctp_v6_scope,
985 .addr_valid = sctp_v6_addr_valid,
986 .inaddr_any = sctp_v6_inaddr_any,
987 .is_any = sctp_v6_is_any,
988 .available = sctp_v6_available,
989 .skb_iif = sctp_v6_skb_iif,
990 .is_ce = sctp_v6_is_ce,
991 .seq_dump_addr = sctp_v6_seq_dump_addr,
992 .ecn_capable = sctp_v6_ecn_capable,
993 .net_header_len = sizeof(struct ipv6hdr),
994 .sockaddr_len = sizeof(struct sockaddr_in6),
995#ifdef CONFIG_COMPAT
996 .compat_setsockopt = compat_ipv6_setsockopt,
997 .compat_getsockopt = compat_ipv6_getsockopt,
998#endif
999};
1000
1001static struct sctp_pf sctp_pf_inet6 = {
1002 .event_msgname = sctp_inet6_event_msgname,
1003 .skb_msgname = sctp_inet6_skb_msgname,
1004 .af_supported = sctp_inet6_af_supported,
1005 .cmp_addr = sctp_inet6_cmp_addr,
1006 .bind_verify = sctp_inet6_bind_verify,
1007 .send_verify = sctp_inet6_send_verify,
1008 .supported_addrs = sctp_inet6_supported_addrs,
1009 .create_accept_sk = sctp_v6_create_accept_sk,
1010 .addr_v4map = sctp_v6_addr_v4map,
1011 .af = &sctp_af_inet6,
1012};
1013
1014/* Initialize IPv6 support and register with socket layer. */
1015void sctp_v6_pf_init(void)
1016{
1017 /* Register the SCTP specific PF_INET6 functions. */
1018 sctp_register_pf(&sctp_pf_inet6, PF_INET6);
1019
1020 /* Register the SCTP specific AF_INET6 functions. */
1021 sctp_register_af(&sctp_af_inet6);
1022}
1023
1024void sctp_v6_pf_exit(void)
1025{
1026 list_del(&sctp_af_inet6.list);
1027}
1028
1029/* Initialize IPv6 support and register with socket layer. */
1030int sctp_v6_protosw_init(void)
1031{
1032 int rc;
1033
1034 rc = proto_register(&sctpv6_prot, 1);
1035 if (rc)
1036 return rc;
1037
1038 /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
1039 inet6_register_protosw(&sctpv6_seqpacket_protosw);
1040 inet6_register_protosw(&sctpv6_stream_protosw);
1041
1042 return 0;
1043}
1044
1045void sctp_v6_protosw_exit(void)
1046{
1047 inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
1048 inet6_unregister_protosw(&sctpv6_stream_protosw);
1049 proto_unregister(&sctpv6_prot);
1050}
1051
1052
1053/* Register with inet6 layer. */
1054int sctp_v6_add_protocol(void)
1055{
1056 /* Register notifier for inet6 address additions/deletions. */
1057 register_inet6addr_notifier(&sctp_inet6addr_notifier);
1058
1059 if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
1060 return -EAGAIN;
1061
1062 return 0;
1063}
1064
1065/* Unregister with inet6 layer. */
1066void sctp_v6_del_protocol(void)
1067{
1068 inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
1069 unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
1070}
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 int err = 0;
132
133 switch (type) {
134 case ICMPV6_PKT_TOOBIG:
135 if (ip6_sk_accept_pmtu(sk))
136 sctp_icmp_frag_needed(sk, asoc, t, info);
137 return;
138 case ICMPV6_PARAMPROB:
139 if (ICMPV6_UNK_NEXTHDR == code) {
140 sctp_icmp_proto_unreachable(sk, asoc, t);
141 return;
142 }
143 break;
144 case NDISC_REDIRECT:
145 sctp_icmp_redirect(sk, t, skb);
146 return;
147 default:
148 break;
149 }
150
151 icmpv6_err_convert(type, code, &err);
152 if (!sock_owned_by_user(sk) && inet6_test_bit(RECVERR6, sk)) {
153 sk->sk_err = err;
154 sk_error_report(sk);
155 } else {
156 WRITE_ONCE(sk->sk_err_soft, err);
157 }
158}
159
160/* ICMP error handler. */
161static int sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
162 u8 type, u8 code, int offset, __be32 info)
163{
164 struct net *net = dev_net(skb->dev);
165 struct sctp_transport *transport;
166 struct sctp_association *asoc;
167 __u16 saveip, savesctp;
168 struct sock *sk;
169
170 /* Fix up skb to look at the embedded net header. */
171 saveip = skb->network_header;
172 savesctp = skb->transport_header;
173 skb_reset_network_header(skb);
174 skb_set_transport_header(skb, offset);
175 sk = sctp_err_lookup(net, AF_INET6, skb, sctp_hdr(skb), &asoc, &transport);
176 /* Put back, the original pointers. */
177 skb->network_header = saveip;
178 skb->transport_header = savesctp;
179 if (!sk) {
180 __ICMP6_INC_STATS(net, __in6_dev_get(skb->dev), ICMP6_MIB_INERRORS);
181 return -ENOENT;
182 }
183
184 sctp_v6_err_handle(transport, skb, type, code, ntohl(info));
185 sctp_err_finish(sk, transport);
186
187 return 0;
188}
189
190int sctp_udp_v6_err(struct sock *sk, struct sk_buff *skb)
191{
192 struct net *net = dev_net(skb->dev);
193 struct sctp_association *asoc;
194 struct sctp_transport *t;
195 struct icmp6hdr *hdr;
196 __u32 info = 0;
197
198 skb->transport_header += sizeof(struct udphdr);
199 sk = sctp_err_lookup(net, AF_INET6, skb, sctp_hdr(skb), &asoc, &t);
200 if (!sk) {
201 __ICMP6_INC_STATS(net, __in6_dev_get(skb->dev), ICMP6_MIB_INERRORS);
202 return -ENOENT;
203 }
204
205 skb->transport_header -= sizeof(struct udphdr);
206 hdr = (struct icmp6hdr *)(skb_network_header(skb) - sizeof(struct icmp6hdr));
207 if (hdr->icmp6_type == NDISC_REDIRECT) {
208 /* can't be handled without outer ip6hdr known, leave it to udpv6_err */
209 sctp_err_finish(sk, t);
210 return 0;
211 }
212 if (hdr->icmp6_type == ICMPV6_PKT_TOOBIG)
213 info = ntohl(hdr->icmp6_mtu);
214 sctp_v6_err_handle(t, skb, hdr->icmp6_type, hdr->icmp6_code, info);
215
216 sctp_err_finish(sk, t);
217 return 1;
218}
219
220static int sctp_v6_xmit(struct sk_buff *skb, struct sctp_transport *t)
221{
222 struct dst_entry *dst = dst_clone(t->dst);
223 struct flowi6 *fl6 = &t->fl.u.ip6;
224 struct sock *sk = skb->sk;
225 struct ipv6_pinfo *np = inet6_sk(sk);
226 __u8 tclass = np->tclass;
227 __be32 label;
228
229 pr_debug("%s: skb:%p, len:%d, src:%pI6 dst:%pI6\n", __func__, skb,
230 skb->len, &fl6->saddr, &fl6->daddr);
231
232 if (t->dscp & SCTP_DSCP_SET_MASK)
233 tclass = t->dscp & SCTP_DSCP_VAL_MASK;
234
235 if (INET_ECN_is_capable(tclass))
236 IP6_ECN_flow_xmit(sk, fl6->flowlabel);
237
238 if (!(t->param_flags & SPP_PMTUD_ENABLE))
239 skb->ignore_df = 1;
240
241 SCTP_INC_STATS(sock_net(sk), SCTP_MIB_OUTSCTPPACKS);
242
243 if (!t->encap_port || !sctp_sk(sk)->udp_port) {
244 int res;
245
246 skb_dst_set(skb, dst);
247 rcu_read_lock();
248 res = ip6_xmit(sk, skb, fl6, sk->sk_mark,
249 rcu_dereference(np->opt),
250 tclass, READ_ONCE(sk->sk_priority));
251 rcu_read_unlock();
252 return res;
253 }
254
255 if (skb_is_gso(skb))
256 skb_shinfo(skb)->gso_type |= SKB_GSO_UDP_TUNNEL_CSUM;
257
258 skb->encapsulation = 1;
259 skb_reset_inner_mac_header(skb);
260 skb_reset_inner_transport_header(skb);
261 skb_set_inner_ipproto(skb, IPPROTO_SCTP);
262 label = ip6_make_flowlabel(sock_net(sk), skb, fl6->flowlabel, true, fl6);
263
264 return udp_tunnel6_xmit_skb(dst, sk, skb, NULL, &fl6->saddr,
265 &fl6->daddr, tclass, ip6_dst_hoplimit(dst),
266 label, sctp_sk(sk)->udp_port, t->encap_port, false);
267}
268
269/* Returns the dst cache entry for the given source and destination ip
270 * addresses.
271 */
272static void sctp_v6_get_dst(struct sctp_transport *t, union sctp_addr *saddr,
273 struct flowi *fl, struct sock *sk)
274{
275 struct sctp_association *asoc = t->asoc;
276 struct dst_entry *dst = NULL;
277 struct flowi _fl;
278 struct flowi6 *fl6 = &_fl.u.ip6;
279 struct sctp_bind_addr *bp;
280 struct ipv6_pinfo *np = inet6_sk(sk);
281 struct sctp_sockaddr_entry *laddr;
282 union sctp_addr *daddr = &t->ipaddr;
283 union sctp_addr dst_saddr;
284 struct in6_addr *final_p, final;
285 enum sctp_scope scope;
286 __u8 matchlen = 0;
287
288 memset(&_fl, 0, sizeof(_fl));
289 fl6->daddr = daddr->v6.sin6_addr;
290 fl6->fl6_dport = daddr->v6.sin6_port;
291 fl6->flowi6_proto = IPPROTO_SCTP;
292 if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
293 fl6->flowi6_oif = daddr->v6.sin6_scope_id;
294 else if (asoc)
295 fl6->flowi6_oif = asoc->base.sk->sk_bound_dev_if;
296 if (t->flowlabel & SCTP_FLOWLABEL_SET_MASK)
297 fl6->flowlabel = htonl(t->flowlabel & SCTP_FLOWLABEL_VAL_MASK);
298
299 if (inet6_test_bit(SNDFLOW, sk) &&
300 (fl6->flowlabel & IPV6_FLOWLABEL_MASK)) {
301 struct ip6_flowlabel *flowlabel;
302
303 flowlabel = fl6_sock_lookup(sk, fl6->flowlabel);
304 if (IS_ERR(flowlabel))
305 goto out;
306 fl6_sock_release(flowlabel);
307 }
308
309 pr_debug("%s: dst=%pI6 ", __func__, &fl6->daddr);
310
311 if (asoc)
312 fl6->fl6_sport = htons(asoc->base.bind_addr.port);
313
314 if (saddr) {
315 fl6->saddr = saddr->v6.sin6_addr;
316 if (!fl6->fl6_sport)
317 fl6->fl6_sport = saddr->v6.sin6_port;
318
319 pr_debug("src=%pI6 - ", &fl6->saddr);
320 }
321
322 rcu_read_lock();
323 final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final);
324 rcu_read_unlock();
325
326 dst = ip6_dst_lookup_flow(sock_net(sk), sk, fl6, final_p);
327 if (!asoc || saddr) {
328 t->dst = dst;
329 memcpy(fl, &_fl, sizeof(_fl));
330 goto out;
331 }
332
333 bp = &asoc->base.bind_addr;
334 scope = sctp_scope(daddr);
335 /* ip6_dst_lookup has filled in the fl6->saddr for us. Check
336 * to see if we can use it.
337 */
338 if (!IS_ERR(dst)) {
339 /* Walk through the bind address list and look for a bind
340 * address that matches the source address of the returned dst.
341 */
342 sctp_v6_to_addr(&dst_saddr, &fl6->saddr, htons(bp->port));
343 rcu_read_lock();
344 list_for_each_entry_rcu(laddr, &bp->address_list, list) {
345 if (!laddr->valid || laddr->state == SCTP_ADDR_DEL ||
346 (laddr->state != SCTP_ADDR_SRC &&
347 !asoc->src_out_of_asoc_ok))
348 continue;
349
350 /* Do not compare against v4 addrs */
351 if ((laddr->a.sa.sa_family == AF_INET6) &&
352 (sctp_v6_cmp_addr(&dst_saddr, &laddr->a))) {
353 rcu_read_unlock();
354 t->dst = dst;
355 memcpy(fl, &_fl, sizeof(_fl));
356 goto out;
357 }
358 }
359 rcu_read_unlock();
360 /* None of the bound addresses match the source address of the
361 * dst. So release it.
362 */
363 dst_release(dst);
364 dst = NULL;
365 }
366
367 /* Walk through the bind address list and try to get the
368 * best source address for a given destination.
369 */
370 rcu_read_lock();
371 list_for_each_entry_rcu(laddr, &bp->address_list, list) {
372 struct dst_entry *bdst;
373 __u8 bmatchlen;
374
375 if (!laddr->valid ||
376 laddr->state != SCTP_ADDR_SRC ||
377 laddr->a.sa.sa_family != AF_INET6 ||
378 scope > sctp_scope(&laddr->a))
379 continue;
380
381 fl6->saddr = laddr->a.v6.sin6_addr;
382 fl6->fl6_sport = laddr->a.v6.sin6_port;
383 final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final);
384 bdst = ip6_dst_lookup_flow(sock_net(sk), sk, fl6, final_p);
385
386 if (IS_ERR(bdst))
387 continue;
388
389 if (ipv6_chk_addr(dev_net(bdst->dev),
390 &laddr->a.v6.sin6_addr, bdst->dev, 1)) {
391 if (!IS_ERR_OR_NULL(dst))
392 dst_release(dst);
393 dst = bdst;
394 t->dst = dst;
395 memcpy(fl, &_fl, sizeof(_fl));
396 break;
397 }
398
399 bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a);
400 if (matchlen > bmatchlen) {
401 dst_release(bdst);
402 continue;
403 }
404
405 if (!IS_ERR_OR_NULL(dst))
406 dst_release(dst);
407 dst = bdst;
408 matchlen = bmatchlen;
409 t->dst = dst;
410 memcpy(fl, &_fl, sizeof(_fl));
411 }
412 rcu_read_unlock();
413
414out:
415 if (!IS_ERR_OR_NULL(dst)) {
416 struct rt6_info *rt;
417
418 rt = (struct rt6_info *)dst;
419 t->dst_cookie = rt6_get_cookie(rt);
420 pr_debug("rt6_dst:%pI6/%d rt6_src:%pI6\n",
421 &rt->rt6i_dst.addr, rt->rt6i_dst.plen,
422 &fl->u.ip6.saddr);
423 } else {
424 t->dst = NULL;
425 pr_debug("no route\n");
426 }
427}
428
429/* Returns the number of consecutive initial bits that match in the 2 ipv6
430 * addresses.
431 */
432static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
433 union sctp_addr *s2)
434{
435 return ipv6_addr_diff(&s1->v6.sin6_addr, &s2->v6.sin6_addr);
436}
437
438/* Fills in the source address(saddr) based on the destination address(daddr)
439 * and asoc's bind address list.
440 */
441static void sctp_v6_get_saddr(struct sctp_sock *sk,
442 struct sctp_transport *t,
443 struct flowi *fl)
444{
445 struct flowi6 *fl6 = &fl->u.ip6;
446 union sctp_addr *saddr = &t->saddr;
447
448 pr_debug("%s: asoc:%p dst:%p\n", __func__, t->asoc, t->dst);
449
450 if (t->dst) {
451 saddr->v6.sin6_family = AF_INET6;
452 saddr->v6.sin6_addr = fl6->saddr;
453 }
454}
455
456/* Make a copy of all potential local addresses. */
457static void sctp_v6_copy_addrlist(struct list_head *addrlist,
458 struct net_device *dev)
459{
460 struct inet6_dev *in6_dev;
461 struct inet6_ifaddr *ifp;
462 struct sctp_sockaddr_entry *addr;
463
464 rcu_read_lock();
465 if ((in6_dev = __in6_dev_get(dev)) == NULL) {
466 rcu_read_unlock();
467 return;
468 }
469
470 read_lock_bh(&in6_dev->lock);
471 list_for_each_entry(ifp, &in6_dev->addr_list, if_list) {
472 /* Add the address to the local list. */
473 addr = kzalloc(sizeof(*addr), GFP_ATOMIC);
474 if (addr) {
475 addr->a.v6.sin6_family = AF_INET6;
476 addr->a.v6.sin6_addr = ifp->addr;
477 addr->a.v6.sin6_scope_id = dev->ifindex;
478 addr->valid = 1;
479 INIT_LIST_HEAD(&addr->list);
480 list_add_tail(&addr->list, addrlist);
481 }
482 }
483
484 read_unlock_bh(&in6_dev->lock);
485 rcu_read_unlock();
486}
487
488/* Copy over any ip options */
489static void sctp_v6_copy_ip_options(struct sock *sk, struct sock *newsk)
490{
491 struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
492 struct ipv6_txoptions *opt;
493
494 newnp = inet6_sk(newsk);
495
496 rcu_read_lock();
497 opt = rcu_dereference(np->opt);
498 if (opt) {
499 opt = ipv6_dup_options(newsk, opt);
500 if (!opt)
501 pr_err("%s: Failed to copy ip options\n", __func__);
502 }
503 RCU_INIT_POINTER(newnp->opt, opt);
504 rcu_read_unlock();
505}
506
507/* Account for the IP options */
508static int sctp_v6_ip_options_len(struct sock *sk)
509{
510 struct ipv6_pinfo *np = inet6_sk(sk);
511 struct ipv6_txoptions *opt;
512 int len = 0;
513
514 rcu_read_lock();
515 opt = rcu_dereference(np->opt);
516 if (opt)
517 len = opt->opt_flen + opt->opt_nflen;
518
519 rcu_read_unlock();
520 return len;
521}
522
523/* Initialize a sockaddr_storage from in incoming skb. */
524static void sctp_v6_from_skb(union sctp_addr *addr, struct sk_buff *skb,
525 int is_saddr)
526{
527 /* Always called on head skb, so this is safe */
528 struct sctphdr *sh = sctp_hdr(skb);
529 struct sockaddr_in6 *sa = &addr->v6;
530
531 addr->v6.sin6_family = AF_INET6;
532 addr->v6.sin6_flowinfo = 0; /* FIXME */
533 addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif;
534
535 if (is_saddr) {
536 sa->sin6_port = sh->source;
537 sa->sin6_addr = ipv6_hdr(skb)->saddr;
538 } else {
539 sa->sin6_port = sh->dest;
540 sa->sin6_addr = ipv6_hdr(skb)->daddr;
541 }
542}
543
544/* Initialize an sctp_addr from a socket. */
545static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk)
546{
547 addr->v6.sin6_family = AF_INET6;
548 addr->v6.sin6_port = 0;
549 addr->v6.sin6_addr = sk->sk_v6_rcv_saddr;
550}
551
552/* Initialize sk->sk_rcv_saddr from sctp_addr. */
553static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
554{
555 if (addr->sa.sa_family == AF_INET) {
556 sk->sk_v6_rcv_saddr.s6_addr32[0] = 0;
557 sk->sk_v6_rcv_saddr.s6_addr32[1] = 0;
558 sk->sk_v6_rcv_saddr.s6_addr32[2] = htonl(0x0000ffff);
559 sk->sk_v6_rcv_saddr.s6_addr32[3] =
560 addr->v4.sin_addr.s_addr;
561 } else {
562 sk->sk_v6_rcv_saddr = addr->v6.sin6_addr;
563 }
564}
565
566/* Initialize sk->sk_daddr from sctp_addr. */
567static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
568{
569 if (addr->sa.sa_family == AF_INET) {
570 sk->sk_v6_daddr.s6_addr32[0] = 0;
571 sk->sk_v6_daddr.s6_addr32[1] = 0;
572 sk->sk_v6_daddr.s6_addr32[2] = htonl(0x0000ffff);
573 sk->sk_v6_daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
574 } else {
575 sk->sk_v6_daddr = addr->v6.sin6_addr;
576 }
577}
578
579/* Initialize a sctp_addr from an address parameter. */
580static bool sctp_v6_from_addr_param(union sctp_addr *addr,
581 union sctp_addr_param *param,
582 __be16 port, int iif)
583{
584 if (ntohs(param->v6.param_hdr.length) < sizeof(struct sctp_ipv6addr_param))
585 return false;
586
587 addr->v6.sin6_family = AF_INET6;
588 addr->v6.sin6_port = port;
589 addr->v6.sin6_flowinfo = 0; /* BUG */
590 addr->v6.sin6_addr = param->v6.addr;
591 addr->v6.sin6_scope_id = iif;
592
593 return true;
594}
595
596/* Initialize an address parameter from a sctp_addr and return the length
597 * of the address parameter.
598 */
599static int sctp_v6_to_addr_param(const union sctp_addr *addr,
600 union sctp_addr_param *param)
601{
602 int length = sizeof(struct sctp_ipv6addr_param);
603
604 param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS;
605 param->v6.param_hdr.length = htons(length);
606 param->v6.addr = addr->v6.sin6_addr;
607
608 return length;
609}
610
611/* Initialize a sctp_addr from struct in6_addr. */
612static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr,
613 __be16 port)
614{
615 addr->sa.sa_family = AF_INET6;
616 addr->v6.sin6_port = port;
617 addr->v6.sin6_flowinfo = 0;
618 addr->v6.sin6_addr = *saddr;
619 addr->v6.sin6_scope_id = 0;
620}
621
622static int __sctp_v6_cmp_addr(const union sctp_addr *addr1,
623 const union sctp_addr *addr2)
624{
625 if (addr1->sa.sa_family != addr2->sa.sa_family) {
626 if (addr1->sa.sa_family == AF_INET &&
627 addr2->sa.sa_family == AF_INET6 &&
628 ipv6_addr_v4mapped(&addr2->v6.sin6_addr) &&
629 addr2->v6.sin6_addr.s6_addr32[3] ==
630 addr1->v4.sin_addr.s_addr)
631 return 1;
632
633 if (addr2->sa.sa_family == AF_INET &&
634 addr1->sa.sa_family == AF_INET6 &&
635 ipv6_addr_v4mapped(&addr1->v6.sin6_addr) &&
636 addr1->v6.sin6_addr.s6_addr32[3] ==
637 addr2->v4.sin_addr.s_addr)
638 return 1;
639
640 return 0;
641 }
642
643 if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))
644 return 0;
645
646 /* If this is a linklocal address, compare the scope_id. */
647 if ((ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) &&
648 addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&
649 addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)
650 return 0;
651
652 return 1;
653}
654
655/* Compare addresses exactly.
656 * v4-mapped-v6 is also in consideration.
657 */
658static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
659 const union sctp_addr *addr2)
660{
661 return __sctp_v6_cmp_addr(addr1, addr2) &&
662 addr1->v6.sin6_port == addr2->v6.sin6_port;
663}
664
665/* Initialize addr struct to INADDR_ANY. */
666static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port)
667{
668 memset(addr, 0x00, sizeof(union sctp_addr));
669 addr->v6.sin6_family = AF_INET6;
670 addr->v6.sin6_port = port;
671}
672
673/* Is this a wildcard address? */
674static int sctp_v6_is_any(const union sctp_addr *addr)
675{
676 return ipv6_addr_any(&addr->v6.sin6_addr);
677}
678
679/* Should this be available for binding? */
680static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp)
681{
682 const struct in6_addr *in6 = (const struct in6_addr *)&addr->v6.sin6_addr;
683 struct sock *sk = &sp->inet.sk;
684 struct net *net = sock_net(sk);
685 struct net_device *dev = NULL;
686 int type;
687
688 type = ipv6_addr_type(in6);
689 if (IPV6_ADDR_ANY == type)
690 return 1;
691 if (type == IPV6_ADDR_MAPPED) {
692 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
693 return 0;
694 sctp_v6_map_v4(addr);
695 return sctp_get_af_specific(AF_INET)->available(addr, sp);
696 }
697 if (!(type & IPV6_ADDR_UNICAST))
698 return 0;
699
700 if (sk->sk_bound_dev_if) {
701 dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if);
702 if (!dev)
703 return 0;
704 }
705
706 return ipv6_can_nonlocal_bind(net, &sp->inet) ||
707 ipv6_chk_addr(net, in6, dev, 0);
708}
709
710/* This function checks if the address is a valid address to be used for
711 * SCTP.
712 *
713 * Output:
714 * Return 0 - If the address is a non-unicast or an illegal address.
715 * Return 1 - If the address is a unicast.
716 */
717static int sctp_v6_addr_valid(union sctp_addr *addr,
718 struct sctp_sock *sp,
719 const struct sk_buff *skb)
720{
721 int ret = ipv6_addr_type(&addr->v6.sin6_addr);
722
723 /* Support v4-mapped-v6 address. */
724 if (ret == IPV6_ADDR_MAPPED) {
725 /* Note: This routine is used in input, so v4-mapped-v6
726 * are disallowed here when there is no sctp_sock.
727 */
728 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
729 return 0;
730 sctp_v6_map_v4(addr);
731 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb);
732 }
733
734 /* Is this a non-unicast address */
735 if (!(ret & IPV6_ADDR_UNICAST))
736 return 0;
737
738 return 1;
739}
740
741/* What is the scope of 'addr'? */
742static enum sctp_scope sctp_v6_scope(union sctp_addr *addr)
743{
744 enum sctp_scope retval;
745 int v6scope;
746
747 /* The IPv6 scope is really a set of bit fields.
748 * See IFA_* in <net/if_inet6.h>. Map to a generic SCTP scope.
749 */
750
751 v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
752 switch (v6scope) {
753 case IFA_HOST:
754 retval = SCTP_SCOPE_LOOPBACK;
755 break;
756 case IFA_LINK:
757 retval = SCTP_SCOPE_LINK;
758 break;
759 case IFA_SITE:
760 retval = SCTP_SCOPE_PRIVATE;
761 break;
762 default:
763 retval = SCTP_SCOPE_GLOBAL;
764 break;
765 }
766
767 return retval;
768}
769
770/* Create and initialize a new sk for the socket to be returned by accept(). */
771static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
772 struct sctp_association *asoc,
773 bool kern)
774{
775 struct sock *newsk;
776 struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
777 struct sctp6_sock *newsctp6sk;
778
779 newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot, kern);
780 if (!newsk)
781 goto out;
782
783 sock_init_data(NULL, newsk);
784
785 sctp_copy_sock(newsk, sk, asoc);
786 sock_reset_flag(sk, SOCK_ZAPPED);
787
788 newsctp6sk = (struct sctp6_sock *)newsk;
789 inet_sk(newsk)->pinet6 = &newsctp6sk->inet6;
790
791 sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped;
792
793 newnp = inet6_sk(newsk);
794
795 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
796 newnp->ipv6_mc_list = NULL;
797 newnp->ipv6_ac_list = NULL;
798 newnp->ipv6_fl_list = NULL;
799
800 sctp_v6_copy_ip_options(sk, newsk);
801
802 /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
803 * and getpeername().
804 */
805 sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
806
807 newsk->sk_v6_rcv_saddr = sk->sk_v6_rcv_saddr;
808
809 if (newsk->sk_prot->init(newsk)) {
810 sk_common_release(newsk);
811 newsk = NULL;
812 }
813
814out:
815 return newsk;
816}
817
818/* Format a sockaddr for return to user space. This makes sure the return is
819 * AF_INET or AF_INET6 depending on the SCTP_I_WANT_MAPPED_V4_ADDR option.
820 */
821static int sctp_v6_addr_to_user(struct sctp_sock *sp, union sctp_addr *addr)
822{
823 if (sp->v4mapped) {
824 if (addr->sa.sa_family == AF_INET)
825 sctp_v4_map_v6(addr);
826 } else {
827 if (addr->sa.sa_family == AF_INET6 &&
828 ipv6_addr_v4mapped(&addr->v6.sin6_addr))
829 sctp_v6_map_v4(addr);
830 }
831
832 if (addr->sa.sa_family == AF_INET) {
833 memset(addr->v4.sin_zero, 0, sizeof(addr->v4.sin_zero));
834 return sizeof(struct sockaddr_in);
835 }
836 return sizeof(struct sockaddr_in6);
837}
838
839/* Where did this skb come from? */
840static int sctp_v6_skb_iif(const struct sk_buff *skb)
841{
842 return inet6_iif(skb);
843}
844
845static int sctp_v6_skb_sdif(const struct sk_buff *skb)
846{
847 return inet6_sdif(skb);
848}
849
850/* Was this packet marked by Explicit Congestion Notification? */
851static int sctp_v6_is_ce(const struct sk_buff *skb)
852{
853 return *((__u32 *)(ipv6_hdr(skb))) & (__force __u32)htonl(1 << 20);
854}
855
856/* Dump the v6 addr to the seq file. */
857static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
858{
859 seq_printf(seq, "%pI6 ", &addr->v6.sin6_addr);
860}
861
862static void sctp_v6_ecn_capable(struct sock *sk)
863{
864 inet6_sk(sk)->tclass |= INET_ECN_ECT_0;
865}
866
867/* Initialize a PF_INET msgname from a ulpevent. */
868static void sctp_inet6_event_msgname(struct sctp_ulpevent *event,
869 char *msgname, int *addrlen)
870{
871 union sctp_addr *addr;
872 struct sctp_association *asoc;
873 union sctp_addr *paddr;
874
875 if (!msgname)
876 return;
877
878 addr = (union sctp_addr *)msgname;
879 asoc = event->asoc;
880 paddr = &asoc->peer.primary_addr;
881
882 if (paddr->sa.sa_family == AF_INET) {
883 addr->v4.sin_family = AF_INET;
884 addr->v4.sin_port = htons(asoc->peer.port);
885 addr->v4.sin_addr = paddr->v4.sin_addr;
886 } else {
887 addr->v6.sin6_family = AF_INET6;
888 addr->v6.sin6_flowinfo = 0;
889 if (ipv6_addr_type(&paddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
890 addr->v6.sin6_scope_id = paddr->v6.sin6_scope_id;
891 else
892 addr->v6.sin6_scope_id = 0;
893 addr->v6.sin6_port = htons(asoc->peer.port);
894 addr->v6.sin6_addr = paddr->v6.sin6_addr;
895 }
896
897 *addrlen = sctp_v6_addr_to_user(sctp_sk(asoc->base.sk), addr);
898}
899
900/* Initialize a msg_name from an inbound skb. */
901static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname,
902 int *addr_len)
903{
904 union sctp_addr *addr;
905 struct sctphdr *sh;
906
907 if (!msgname)
908 return;
909
910 addr = (union sctp_addr *)msgname;
911 sh = sctp_hdr(skb);
912
913 if (ip_hdr(skb)->version == 4) {
914 addr->v4.sin_family = AF_INET;
915 addr->v4.sin_port = sh->source;
916 addr->v4.sin_addr.s_addr = ip_hdr(skb)->saddr;
917 } else {
918 addr->v6.sin6_family = AF_INET6;
919 addr->v6.sin6_flowinfo = 0;
920 addr->v6.sin6_port = sh->source;
921 addr->v6.sin6_addr = ipv6_hdr(skb)->saddr;
922 if (ipv6_addr_type(&addr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
923 addr->v6.sin6_scope_id = sctp_v6_skb_iif(skb);
924 else
925 addr->v6.sin6_scope_id = 0;
926 }
927
928 *addr_len = sctp_v6_addr_to_user(sctp_sk(skb->sk), addr);
929}
930
931/* Do we support this AF? */
932static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp)
933{
934 switch (family) {
935 case AF_INET6:
936 return 1;
937 /* v4-mapped-v6 addresses */
938 case AF_INET:
939 if (!ipv6_only_sock(sctp_opt2sk(sp)))
940 return 1;
941 fallthrough;
942 default:
943 return 0;
944 }
945}
946
947/* Address matching with wildcards allowed. This extra level
948 * of indirection lets us choose whether a PF_INET6 should
949 * disallow any v4 addresses if we so choose.
950 */
951static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
952 const union sctp_addr *addr2,
953 struct sctp_sock *opt)
954{
955 struct sock *sk = sctp_opt2sk(opt);
956 struct sctp_af *af1, *af2;
957
958 af1 = sctp_get_af_specific(addr1->sa.sa_family);
959 af2 = sctp_get_af_specific(addr2->sa.sa_family);
960
961 if (!af1 || !af2)
962 return 0;
963
964 /* If the socket is IPv6 only, v4 addrs will not match */
965 if (ipv6_only_sock(sk) && af1 != af2)
966 return 0;
967
968 /* Today, wildcard AF_INET/AF_INET6. */
969 if (sctp_is_any(sk, addr1) || sctp_is_any(sk, addr2))
970 return 1;
971
972 if (addr1->sa.sa_family == AF_INET && addr2->sa.sa_family == AF_INET)
973 return addr1->v4.sin_addr.s_addr == addr2->v4.sin_addr.s_addr;
974
975 return __sctp_v6_cmp_addr(addr1, addr2);
976}
977
978/* Verify that the provided sockaddr looks bindable. Common verification,
979 * has already been taken care of.
980 */
981static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
982{
983 struct sctp_af *af;
984
985 /* ASSERT: address family has already been verified. */
986 if (addr->sa.sa_family != AF_INET6)
987 af = sctp_get_af_specific(addr->sa.sa_family);
988 else {
989 int type = ipv6_addr_type(&addr->v6.sin6_addr);
990 struct net_device *dev;
991
992 if (type & IPV6_ADDR_LINKLOCAL) {
993 struct net *net;
994 if (!addr->v6.sin6_scope_id)
995 return 0;
996 net = sock_net(&opt->inet.sk);
997 rcu_read_lock();
998 dev = dev_get_by_index_rcu(net, addr->v6.sin6_scope_id);
999 if (!dev || !(ipv6_can_nonlocal_bind(net, &opt->inet) ||
1000 ipv6_chk_addr(net, &addr->v6.sin6_addr,
1001 dev, 0))) {
1002 rcu_read_unlock();
1003 return 0;
1004 }
1005 rcu_read_unlock();
1006 }
1007
1008 af = opt->pf->af;
1009 }
1010 return af->available(addr, opt);
1011}
1012
1013/* Verify that the provided sockaddr looks sendable. Common verification,
1014 * has already been taken care of.
1015 */
1016static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
1017{
1018 struct sctp_af *af = NULL;
1019
1020 /* ASSERT: address family has already been verified. */
1021 if (addr->sa.sa_family != AF_INET6)
1022 af = sctp_get_af_specific(addr->sa.sa_family);
1023 else {
1024 int type = ipv6_addr_type(&addr->v6.sin6_addr);
1025 struct net_device *dev;
1026
1027 if (type & IPV6_ADDR_LINKLOCAL) {
1028 if (!addr->v6.sin6_scope_id)
1029 return 0;
1030 rcu_read_lock();
1031 dev = dev_get_by_index_rcu(sock_net(&opt->inet.sk),
1032 addr->v6.sin6_scope_id);
1033 rcu_read_unlock();
1034 if (!dev)
1035 return 0;
1036 }
1037 af = opt->pf->af;
1038 }
1039
1040 return af != NULL;
1041}
1042
1043/* Fill in Supported Address Type information for INIT and INIT-ACK
1044 * chunks. Note: In the future, we may want to look at sock options
1045 * to determine whether a PF_INET6 socket really wants to have IPV4
1046 * addresses.
1047 * Returns number of addresses supported.
1048 */
1049static int sctp_inet6_supported_addrs(const struct sctp_sock *opt,
1050 __be16 *types)
1051{
1052 types[0] = SCTP_PARAM_IPV6_ADDRESS;
1053 if (!opt || !ipv6_only_sock(sctp_opt2sk(opt))) {
1054 types[1] = SCTP_PARAM_IPV4_ADDRESS;
1055 return 2;
1056 }
1057 return 1;
1058}
1059
1060/* Handle SCTP_I_WANT_MAPPED_V4_ADDR for getpeername() and getsockname() */
1061static int sctp_getname(struct socket *sock, struct sockaddr *uaddr,
1062 int peer)
1063{
1064 int rc;
1065
1066 rc = inet6_getname(sock, uaddr, peer);
1067
1068 if (rc < 0)
1069 return rc;
1070
1071 rc = sctp_v6_addr_to_user(sctp_sk(sock->sk),
1072 (union sctp_addr *)uaddr);
1073
1074 return rc;
1075}
1076
1077static const struct proto_ops inet6_seqpacket_ops = {
1078 .family = PF_INET6,
1079 .owner = THIS_MODULE,
1080 .release = inet6_release,
1081 .bind = inet6_bind,
1082 .connect = sctp_inet_connect,
1083 .socketpair = sock_no_socketpair,
1084 .accept = inet_accept,
1085 .getname = sctp_getname,
1086 .poll = sctp_poll,
1087 .ioctl = inet6_ioctl,
1088 .gettstamp = sock_gettstamp,
1089 .listen = sctp_inet_listen,
1090 .shutdown = inet_shutdown,
1091 .setsockopt = sock_common_setsockopt,
1092 .getsockopt = sock_common_getsockopt,
1093 .sendmsg = inet_sendmsg,
1094 .recvmsg = inet_recvmsg,
1095 .mmap = sock_no_mmap,
1096#ifdef CONFIG_COMPAT
1097 .compat_ioctl = inet6_compat_ioctl,
1098#endif
1099};
1100
1101static struct inet_protosw sctpv6_seqpacket_protosw = {
1102 .type = SOCK_SEQPACKET,
1103 .protocol = IPPROTO_SCTP,
1104 .prot = &sctpv6_prot,
1105 .ops = &inet6_seqpacket_ops,
1106 .flags = SCTP_PROTOSW_FLAG
1107};
1108static struct inet_protosw sctpv6_stream_protosw = {
1109 .type = SOCK_STREAM,
1110 .protocol = IPPROTO_SCTP,
1111 .prot = &sctpv6_prot,
1112 .ops = &inet6_seqpacket_ops,
1113 .flags = SCTP_PROTOSW_FLAG,
1114};
1115
1116static int sctp6_rcv(struct sk_buff *skb)
1117{
1118 SCTP_INPUT_CB(skb)->encap_port = 0;
1119 return sctp_rcv(skb) ? -1 : 0;
1120}
1121
1122static const struct inet6_protocol sctpv6_protocol = {
1123 .handler = sctp6_rcv,
1124 .err_handler = sctp_v6_err,
1125 .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
1126};
1127
1128static struct sctp_af sctp_af_inet6 = {
1129 .sa_family = AF_INET6,
1130 .sctp_xmit = sctp_v6_xmit,
1131 .setsockopt = ipv6_setsockopt,
1132 .getsockopt = ipv6_getsockopt,
1133 .get_dst = sctp_v6_get_dst,
1134 .get_saddr = sctp_v6_get_saddr,
1135 .copy_addrlist = sctp_v6_copy_addrlist,
1136 .from_skb = sctp_v6_from_skb,
1137 .from_sk = sctp_v6_from_sk,
1138 .from_addr_param = sctp_v6_from_addr_param,
1139 .to_addr_param = sctp_v6_to_addr_param,
1140 .cmp_addr = sctp_v6_cmp_addr,
1141 .scope = sctp_v6_scope,
1142 .addr_valid = sctp_v6_addr_valid,
1143 .inaddr_any = sctp_v6_inaddr_any,
1144 .is_any = sctp_v6_is_any,
1145 .available = sctp_v6_available,
1146 .skb_iif = sctp_v6_skb_iif,
1147 .skb_sdif = sctp_v6_skb_sdif,
1148 .is_ce = sctp_v6_is_ce,
1149 .seq_dump_addr = sctp_v6_seq_dump_addr,
1150 .ecn_capable = sctp_v6_ecn_capable,
1151 .net_header_len = sizeof(struct ipv6hdr),
1152 .sockaddr_len = sizeof(struct sockaddr_in6),
1153 .ip_options_len = sctp_v6_ip_options_len,
1154};
1155
1156static struct sctp_pf sctp_pf_inet6 = {
1157 .event_msgname = sctp_inet6_event_msgname,
1158 .skb_msgname = sctp_inet6_skb_msgname,
1159 .af_supported = sctp_inet6_af_supported,
1160 .cmp_addr = sctp_inet6_cmp_addr,
1161 .bind_verify = sctp_inet6_bind_verify,
1162 .send_verify = sctp_inet6_send_verify,
1163 .supported_addrs = sctp_inet6_supported_addrs,
1164 .create_accept_sk = sctp_v6_create_accept_sk,
1165 .addr_to_user = sctp_v6_addr_to_user,
1166 .to_sk_saddr = sctp_v6_to_sk_saddr,
1167 .to_sk_daddr = sctp_v6_to_sk_daddr,
1168 .copy_ip_options = sctp_v6_copy_ip_options,
1169 .af = &sctp_af_inet6,
1170};
1171
1172/* Initialize IPv6 support and register with socket layer. */
1173void sctp_v6_pf_init(void)
1174{
1175 /* Register the SCTP specific PF_INET6 functions. */
1176 sctp_register_pf(&sctp_pf_inet6, PF_INET6);
1177
1178 /* Register the SCTP specific AF_INET6 functions. */
1179 sctp_register_af(&sctp_af_inet6);
1180}
1181
1182void sctp_v6_pf_exit(void)
1183{
1184 list_del(&sctp_af_inet6.list);
1185}
1186
1187/* Initialize IPv6 support and register with socket layer. */
1188int sctp_v6_protosw_init(void)
1189{
1190 int rc;
1191
1192 rc = proto_register(&sctpv6_prot, 1);
1193 if (rc)
1194 return rc;
1195
1196 /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
1197 inet6_register_protosw(&sctpv6_seqpacket_protosw);
1198 inet6_register_protosw(&sctpv6_stream_protosw);
1199
1200 return 0;
1201}
1202
1203void sctp_v6_protosw_exit(void)
1204{
1205 inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
1206 inet6_unregister_protosw(&sctpv6_stream_protosw);
1207 proto_unregister(&sctpv6_prot);
1208}
1209
1210
1211/* Register with inet6 layer. */
1212int sctp_v6_add_protocol(void)
1213{
1214 /* Register notifier for inet6 address additions/deletions. */
1215 register_inet6addr_notifier(&sctp_inet6addr_notifier);
1216
1217 if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
1218 return -EAGAIN;
1219
1220 return 0;
1221}
1222
1223/* Unregister with inet6 layer. */
1224void sctp_v6_del_protocol(void)
1225{
1226 inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
1227 unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
1228}