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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, write to
25 * the Free Software Foundation, 59 Temple Place - Suite 330,
26 * Boston, MA 02111-1307, USA.
27 *
28 * Please send any bug reports or fixes you make to the
29 * email address(es):
30 * lksctp developers <lksctp-developers@lists.sourceforge.net>
31 *
32 * Or submit a bug report through the following website:
33 * http://www.sf.net/projects/lksctp
34 *
35 * Written or modified by:
36 * Le Yanqun <yanqun.le@nokia.com>
37 * Hui Huang <hui.huang@nokia.com>
38 * La Monte H.P. Yarroll <piggy@acm.org>
39 * Sridhar Samudrala <sri@us.ibm.com>
40 * Jon Grimm <jgrimm@us.ibm.com>
41 * Ardelle Fan <ardelle.fan@intel.com>
42 *
43 * Based on:
44 * linux/net/ipv6/tcp_ipv6.c
45 *
46 * Any bugs reported given to us we will try to fix... any fixes shared will
47 * be incorporated into the next SCTP release.
48 */
49
50#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
51
52#include <linux/module.h>
53#include <linux/errno.h>
54#include <linux/types.h>
55#include <linux/socket.h>
56#include <linux/sockios.h>
57#include <linux/net.h>
58#include <linux/in.h>
59#include <linux/in6.h>
60#include <linux/netdevice.h>
61#include <linux/init.h>
62#include <linux/ipsec.h>
63#include <linux/slab.h>
64
65#include <linux/ipv6.h>
66#include <linux/icmpv6.h>
67#include <linux/random.h>
68#include <linux/seq_file.h>
69
70#include <net/protocol.h>
71#include <net/ndisc.h>
72#include <net/ip.h>
73#include <net/ipv6.h>
74#include <net/transp_v6.h>
75#include <net/addrconf.h>
76#include <net/ip6_route.h>
77#include <net/inet_common.h>
78#include <net/inet_ecn.h>
79#include <net/sctp/sctp.h>
80
81#include <asm/uaccess.h>
82
83static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
84 union sctp_addr *s2);
85static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr,
86 __be16 port);
87static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
88 const union sctp_addr *addr2);
89
90/* Event handler for inet6 address addition/deletion events.
91 * The sctp_local_addr_list needs to be protocted by a spin lock since
92 * multiple notifiers (say IPv4 and IPv6) may be running at the same
93 * time and thus corrupt the list.
94 * The reader side is protected with RCU.
95 */
96static int sctp_inet6addr_event(struct notifier_block *this, unsigned long ev,
97 void *ptr)
98{
99 struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
100 struct sctp_sockaddr_entry *addr = NULL;
101 struct sctp_sockaddr_entry *temp;
102 int found = 0;
103
104 switch (ev) {
105 case NETDEV_UP:
106 addr = kmalloc(sizeof(struct sctp_sockaddr_entry), GFP_ATOMIC);
107 if (addr) {
108 addr->a.v6.sin6_family = AF_INET6;
109 addr->a.v6.sin6_port = 0;
110 ipv6_addr_copy(&addr->a.v6.sin6_addr, &ifa->addr);
111 addr->a.v6.sin6_scope_id = ifa->idev->dev->ifindex;
112 addr->valid = 1;
113 spin_lock_bh(&sctp_local_addr_lock);
114 list_add_tail_rcu(&addr->list, &sctp_local_addr_list);
115 sctp_addr_wq_mgmt(addr, SCTP_ADDR_NEW);
116 spin_unlock_bh(&sctp_local_addr_lock);
117 }
118 break;
119 case NETDEV_DOWN:
120 spin_lock_bh(&sctp_local_addr_lock);
121 list_for_each_entry_safe(addr, temp,
122 &sctp_local_addr_list, list) {
123 if (addr->a.sa.sa_family == AF_INET6 &&
124 ipv6_addr_equal(&addr->a.v6.sin6_addr,
125 &ifa->addr)) {
126 sctp_addr_wq_mgmt(addr, SCTP_ADDR_DEL);
127 found = 1;
128 addr->valid = 0;
129 list_del_rcu(&addr->list);
130 break;
131 }
132 }
133 spin_unlock_bh(&sctp_local_addr_lock);
134 if (found)
135 kfree_rcu(addr, rcu);
136 break;
137 }
138
139 return NOTIFY_DONE;
140}
141
142static struct notifier_block sctp_inet6addr_notifier = {
143 .notifier_call = sctp_inet6addr_event,
144};
145
146/* ICMP error handler. */
147SCTP_STATIC void sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
148 u8 type, u8 code, int offset, __be32 info)
149{
150 struct inet6_dev *idev;
151 struct sock *sk;
152 struct sctp_association *asoc;
153 struct sctp_transport *transport;
154 struct ipv6_pinfo *np;
155 sk_buff_data_t saveip, savesctp;
156 int err;
157
158 idev = in6_dev_get(skb->dev);
159
160 /* Fix up skb to look at the embedded net header. */
161 saveip = skb->network_header;
162 savesctp = skb->transport_header;
163 skb_reset_network_header(skb);
164 skb_set_transport_header(skb, offset);
165 sk = sctp_err_lookup(AF_INET6, skb, sctp_hdr(skb), &asoc, &transport);
166 /* Put back, the original pointers. */
167 skb->network_header = saveip;
168 skb->transport_header = savesctp;
169 if (!sk) {
170 ICMP6_INC_STATS_BH(dev_net(skb->dev), idev, ICMP6_MIB_INERRORS);
171 goto out;
172 }
173
174 /* Warning: The sock lock is held. Remember to call
175 * sctp_err_finish!
176 */
177
178 switch (type) {
179 case ICMPV6_PKT_TOOBIG:
180 sctp_icmp_frag_needed(sk, asoc, transport, ntohl(info));
181 goto out_unlock;
182 case ICMPV6_PARAMPROB:
183 if (ICMPV6_UNK_NEXTHDR == code) {
184 sctp_icmp_proto_unreachable(sk, asoc, transport);
185 goto out_unlock;
186 }
187 break;
188 default:
189 break;
190 }
191
192 np = inet6_sk(sk);
193 icmpv6_err_convert(type, code, &err);
194 if (!sock_owned_by_user(sk) && np->recverr) {
195 sk->sk_err = err;
196 sk->sk_error_report(sk);
197 } else { /* Only an error on timeout */
198 sk->sk_err_soft = err;
199 }
200
201out_unlock:
202 sctp_err_finish(sk, asoc);
203out:
204 if (likely(idev != NULL))
205 in6_dev_put(idev);
206}
207
208/* Based on tcp_v6_xmit() in tcp_ipv6.c. */
209static int sctp_v6_xmit(struct sk_buff *skb, struct sctp_transport *transport)
210{
211 struct sock *sk = skb->sk;
212 struct ipv6_pinfo *np = inet6_sk(sk);
213 struct flowi6 fl6;
214
215 memset(&fl6, 0, sizeof(fl6));
216
217 fl6.flowi6_proto = sk->sk_protocol;
218
219 /* Fill in the dest address from the route entry passed with the skb
220 * and the source address from the transport.
221 */
222 ipv6_addr_copy(&fl6.daddr, &transport->ipaddr.v6.sin6_addr);
223 ipv6_addr_copy(&fl6.saddr, &transport->saddr.v6.sin6_addr);
224
225 fl6.flowlabel = np->flow_label;
226 IP6_ECN_flow_xmit(sk, fl6.flowlabel);
227 if (ipv6_addr_type(&fl6.saddr) & IPV6_ADDR_LINKLOCAL)
228 fl6.flowi6_oif = transport->saddr.v6.sin6_scope_id;
229 else
230 fl6.flowi6_oif = sk->sk_bound_dev_if;
231
232 if (np->opt && np->opt->srcrt) {
233 struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt;
234 ipv6_addr_copy(&fl6.daddr, rt0->addr);
235 }
236
237 SCTP_DEBUG_PRINTK("%s: skb:%p, len:%d, src:%pI6 dst:%pI6\n",
238 __func__, skb, skb->len,
239 &fl6.saddr, &fl6.daddr);
240
241 SCTP_INC_STATS(SCTP_MIB_OUTSCTPPACKS);
242
243 if (!(transport->param_flags & SPP_PMTUD_ENABLE))
244 skb->local_df = 1;
245
246 return ip6_xmit(sk, skb, &fl6, np->opt);
247}
248
249/* Returns the dst cache entry for the given source and destination ip
250 * addresses.
251 */
252static void sctp_v6_get_dst(struct sctp_transport *t, union sctp_addr *saddr,
253 struct flowi *fl, struct sock *sk)
254{
255 struct sctp_association *asoc = t->asoc;
256 struct dst_entry *dst = NULL;
257 struct flowi6 *fl6 = &fl->u.ip6;
258 struct sctp_bind_addr *bp;
259 struct sctp_sockaddr_entry *laddr;
260 union sctp_addr *baddr = NULL;
261 union sctp_addr *daddr = &t->ipaddr;
262 union sctp_addr dst_saddr;
263 __u8 matchlen = 0;
264 __u8 bmatchlen;
265 sctp_scope_t scope;
266
267 memset(fl6, 0, sizeof(struct flowi6));
268 ipv6_addr_copy(&fl6->daddr, &daddr->v6.sin6_addr);
269 fl6->fl6_dport = daddr->v6.sin6_port;
270 fl6->flowi6_proto = IPPROTO_SCTP;
271 if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
272 fl6->flowi6_oif = daddr->v6.sin6_scope_id;
273
274 SCTP_DEBUG_PRINTK("%s: DST=%pI6 ", __func__, &fl6->daddr);
275
276 if (asoc)
277 fl6->fl6_sport = htons(asoc->base.bind_addr.port);
278
279 if (saddr) {
280 ipv6_addr_copy(&fl6->saddr, &saddr->v6.sin6_addr);
281 fl6->fl6_sport = saddr->v6.sin6_port;
282 SCTP_DEBUG_PRINTK("SRC=%pI6 - ", &fl6->saddr);
283 }
284
285 dst = ip6_dst_lookup_flow(sk, fl6, NULL, false);
286 if (!asoc || saddr)
287 goto out;
288
289 bp = &asoc->base.bind_addr;
290 scope = sctp_scope(daddr);
291 /* ip6_dst_lookup has filled in the fl6->saddr for us. Check
292 * to see if we can use it.
293 */
294 if (!IS_ERR(dst)) {
295 /* Walk through the bind address list and look for a bind
296 * address that matches the source address of the returned dst.
297 */
298 sctp_v6_to_addr(&dst_saddr, &fl6->saddr, htons(bp->port));
299 rcu_read_lock();
300 list_for_each_entry_rcu(laddr, &bp->address_list, list) {
301 if (!laddr->valid || (laddr->state != SCTP_ADDR_SRC))
302 continue;
303
304 /* Do not compare against v4 addrs */
305 if ((laddr->a.sa.sa_family == AF_INET6) &&
306 (sctp_v6_cmp_addr(&dst_saddr, &laddr->a))) {
307 rcu_read_unlock();
308 goto out;
309 }
310 }
311 rcu_read_unlock();
312 /* None of the bound addresses match the source address of the
313 * dst. So release it.
314 */
315 dst_release(dst);
316 dst = NULL;
317 }
318
319 /* Walk through the bind address list and try to get the
320 * best source address for a given destination.
321 */
322 rcu_read_lock();
323 list_for_each_entry_rcu(laddr, &bp->address_list, list) {
324 if (!laddr->valid && laddr->state != SCTP_ADDR_SRC)
325 continue;
326 if ((laddr->a.sa.sa_family == AF_INET6) &&
327 (scope <= sctp_scope(&laddr->a))) {
328 bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a);
329 if (!baddr || (matchlen < bmatchlen)) {
330 baddr = &laddr->a;
331 matchlen = bmatchlen;
332 }
333 }
334 }
335 rcu_read_unlock();
336 if (baddr) {
337 ipv6_addr_copy(&fl6->saddr, &baddr->v6.sin6_addr);
338 fl6->fl6_sport = baddr->v6.sin6_port;
339 dst = ip6_dst_lookup_flow(sk, fl6, NULL, false);
340 }
341
342out:
343 if (!IS_ERR(dst)) {
344 struct rt6_info *rt;
345 rt = (struct rt6_info *)dst;
346 t->dst = dst;
347 SCTP_DEBUG_PRINTK("rt6_dst:%pI6 rt6_src:%pI6\n",
348 &rt->rt6i_dst.addr, &fl6->saddr);
349 } else {
350 t->dst = NULL;
351 SCTP_DEBUG_PRINTK("NO ROUTE\n");
352 }
353}
354
355/* Returns the number of consecutive initial bits that match in the 2 ipv6
356 * addresses.
357 */
358static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
359 union sctp_addr *s2)
360{
361 return ipv6_addr_diff(&s1->v6.sin6_addr, &s2->v6.sin6_addr);
362}
363
364/* Fills in the source address(saddr) based on the destination address(daddr)
365 * and asoc's bind address list.
366 */
367static void sctp_v6_get_saddr(struct sctp_sock *sk,
368 struct sctp_transport *t,
369 struct flowi *fl)
370{
371 struct flowi6 *fl6 = &fl->u.ip6;
372 union sctp_addr *saddr = &t->saddr;
373
374 SCTP_DEBUG_PRINTK("%s: asoc:%p dst:%p\n", __func__, t->asoc, t->dst);
375
376 if (t->dst) {
377 saddr->v6.sin6_family = AF_INET6;
378 ipv6_addr_copy(&saddr->v6.sin6_addr, &fl6->saddr);
379 }
380}
381
382/* Make a copy of all potential local addresses. */
383static void sctp_v6_copy_addrlist(struct list_head *addrlist,
384 struct net_device *dev)
385{
386 struct inet6_dev *in6_dev;
387 struct inet6_ifaddr *ifp;
388 struct sctp_sockaddr_entry *addr;
389
390 rcu_read_lock();
391 if ((in6_dev = __in6_dev_get(dev)) == NULL) {
392 rcu_read_unlock();
393 return;
394 }
395
396 read_lock_bh(&in6_dev->lock);
397 list_for_each_entry(ifp, &in6_dev->addr_list, if_list) {
398 /* Add the address to the local list. */
399 addr = t_new(struct sctp_sockaddr_entry, GFP_ATOMIC);
400 if (addr) {
401 addr->a.v6.sin6_family = AF_INET6;
402 addr->a.v6.sin6_port = 0;
403 ipv6_addr_copy(&addr->a.v6.sin6_addr, &ifp->addr);
404 addr->a.v6.sin6_scope_id = dev->ifindex;
405 addr->valid = 1;
406 INIT_LIST_HEAD(&addr->list);
407 list_add_tail(&addr->list, addrlist);
408 }
409 }
410
411 read_unlock_bh(&in6_dev->lock);
412 rcu_read_unlock();
413}
414
415/* Initialize a sockaddr_storage from in incoming skb. */
416static void sctp_v6_from_skb(union sctp_addr *addr,struct sk_buff *skb,
417 int is_saddr)
418{
419 void *from;
420 __be16 *port;
421 struct sctphdr *sh;
422
423 port = &addr->v6.sin6_port;
424 addr->v6.sin6_family = AF_INET6;
425 addr->v6.sin6_flowinfo = 0; /* FIXME */
426 addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif;
427
428 sh = sctp_hdr(skb);
429 if (is_saddr) {
430 *port = sh->source;
431 from = &ipv6_hdr(skb)->saddr;
432 } else {
433 *port = sh->dest;
434 from = &ipv6_hdr(skb)->daddr;
435 }
436 ipv6_addr_copy(&addr->v6.sin6_addr, from);
437}
438
439/* Initialize an sctp_addr from a socket. */
440static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk)
441{
442 addr->v6.sin6_family = AF_INET6;
443 addr->v6.sin6_port = 0;
444 ipv6_addr_copy(&addr->v6.sin6_addr, &inet6_sk(sk)->rcv_saddr);
445}
446
447/* Initialize sk->sk_rcv_saddr from sctp_addr. */
448static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
449{
450 if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
451 inet6_sk(sk)->rcv_saddr.s6_addr32[0] = 0;
452 inet6_sk(sk)->rcv_saddr.s6_addr32[1] = 0;
453 inet6_sk(sk)->rcv_saddr.s6_addr32[2] = htonl(0x0000ffff);
454 inet6_sk(sk)->rcv_saddr.s6_addr32[3] =
455 addr->v4.sin_addr.s_addr;
456 } else {
457 ipv6_addr_copy(&inet6_sk(sk)->rcv_saddr, &addr->v6.sin6_addr);
458 }
459}
460
461/* Initialize sk->sk_daddr from sctp_addr. */
462static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
463{
464 if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
465 inet6_sk(sk)->daddr.s6_addr32[0] = 0;
466 inet6_sk(sk)->daddr.s6_addr32[1] = 0;
467 inet6_sk(sk)->daddr.s6_addr32[2] = htonl(0x0000ffff);
468 inet6_sk(sk)->daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
469 } else {
470 ipv6_addr_copy(&inet6_sk(sk)->daddr, &addr->v6.sin6_addr);
471 }
472}
473
474/* Initialize a sctp_addr from an address parameter. */
475static void sctp_v6_from_addr_param(union sctp_addr *addr,
476 union sctp_addr_param *param,
477 __be16 port, int iif)
478{
479 addr->v6.sin6_family = AF_INET6;
480 addr->v6.sin6_port = port;
481 addr->v6.sin6_flowinfo = 0; /* BUG */
482 ipv6_addr_copy(&addr->v6.sin6_addr, ¶m->v6.addr);
483 addr->v6.sin6_scope_id = iif;
484}
485
486/* Initialize an address parameter from a sctp_addr and return the length
487 * of the address parameter.
488 */
489static int sctp_v6_to_addr_param(const union sctp_addr *addr,
490 union sctp_addr_param *param)
491{
492 int length = sizeof(sctp_ipv6addr_param_t);
493
494 param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS;
495 param->v6.param_hdr.length = htons(length);
496 ipv6_addr_copy(¶m->v6.addr, &addr->v6.sin6_addr);
497
498 return length;
499}
500
501/* Initialize a sctp_addr from struct in6_addr. */
502static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr,
503 __be16 port)
504{
505 addr->sa.sa_family = AF_INET6;
506 addr->v6.sin6_port = port;
507 ipv6_addr_copy(&addr->v6.sin6_addr, saddr);
508}
509
510/* Compare addresses exactly.
511 * v4-mapped-v6 is also in consideration.
512 */
513static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
514 const union sctp_addr *addr2)
515{
516 if (addr1->sa.sa_family != addr2->sa.sa_family) {
517 if (addr1->sa.sa_family == AF_INET &&
518 addr2->sa.sa_family == AF_INET6 &&
519 ipv6_addr_v4mapped(&addr2->v6.sin6_addr)) {
520 if (addr2->v6.sin6_port == addr1->v4.sin_port &&
521 addr2->v6.sin6_addr.s6_addr32[3] ==
522 addr1->v4.sin_addr.s_addr)
523 return 1;
524 }
525 if (addr2->sa.sa_family == AF_INET &&
526 addr1->sa.sa_family == AF_INET6 &&
527 ipv6_addr_v4mapped(&addr1->v6.sin6_addr)) {
528 if (addr1->v6.sin6_port == addr2->v4.sin_port &&
529 addr1->v6.sin6_addr.s6_addr32[3] ==
530 addr2->v4.sin_addr.s_addr)
531 return 1;
532 }
533 return 0;
534 }
535 if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))
536 return 0;
537 /* If this is a linklocal address, compare the scope_id. */
538 if (ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) {
539 if (addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&
540 (addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)) {
541 return 0;
542 }
543 }
544
545 return 1;
546}
547
548/* Initialize addr struct to INADDR_ANY. */
549static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port)
550{
551 memset(addr, 0x00, sizeof(union sctp_addr));
552 addr->v6.sin6_family = AF_INET6;
553 addr->v6.sin6_port = port;
554}
555
556/* Is this a wildcard address? */
557static int sctp_v6_is_any(const union sctp_addr *addr)
558{
559 return ipv6_addr_any(&addr->v6.sin6_addr);
560}
561
562/* Should this be available for binding? */
563static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp)
564{
565 int type;
566 const struct in6_addr *in6 = (const struct in6_addr *)&addr->v6.sin6_addr;
567
568 type = ipv6_addr_type(in6);
569 if (IPV6_ADDR_ANY == type)
570 return 1;
571 if (type == IPV6_ADDR_MAPPED) {
572 if (sp && !sp->v4mapped)
573 return 0;
574 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
575 return 0;
576 sctp_v6_map_v4(addr);
577 return sctp_get_af_specific(AF_INET)->available(addr, sp);
578 }
579 if (!(type & IPV6_ADDR_UNICAST))
580 return 0;
581
582 return ipv6_chk_addr(&init_net, in6, NULL, 0);
583}
584
585/* This function checks if the address is a valid address to be used for
586 * SCTP.
587 *
588 * Output:
589 * Return 0 - If the address is a non-unicast or an illegal address.
590 * Return 1 - If the address is a unicast.
591 */
592static int sctp_v6_addr_valid(union sctp_addr *addr,
593 struct sctp_sock *sp,
594 const struct sk_buff *skb)
595{
596 int ret = ipv6_addr_type(&addr->v6.sin6_addr);
597
598 /* Support v4-mapped-v6 address. */
599 if (ret == IPV6_ADDR_MAPPED) {
600 /* Note: This routine is used in input, so v4-mapped-v6
601 * are disallowed here when there is no sctp_sock.
602 */
603 if (!sp || !sp->v4mapped)
604 return 0;
605 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
606 return 0;
607 sctp_v6_map_v4(addr);
608 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb);
609 }
610
611 /* Is this a non-unicast address */
612 if (!(ret & IPV6_ADDR_UNICAST))
613 return 0;
614
615 return 1;
616}
617
618/* What is the scope of 'addr'? */
619static sctp_scope_t sctp_v6_scope(union sctp_addr *addr)
620{
621 int v6scope;
622 sctp_scope_t retval;
623
624 /* The IPv6 scope is really a set of bit fields.
625 * See IFA_* in <net/if_inet6.h>. Map to a generic SCTP scope.
626 */
627
628 v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
629 switch (v6scope) {
630 case IFA_HOST:
631 retval = SCTP_SCOPE_LOOPBACK;
632 break;
633 case IFA_LINK:
634 retval = SCTP_SCOPE_LINK;
635 break;
636 case IFA_SITE:
637 retval = SCTP_SCOPE_PRIVATE;
638 break;
639 default:
640 retval = SCTP_SCOPE_GLOBAL;
641 break;
642 }
643
644 return retval;
645}
646
647/* Create and initialize a new sk for the socket to be returned by accept(). */
648static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
649 struct sctp_association *asoc)
650{
651 struct sock *newsk;
652 struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
653 struct sctp6_sock *newsctp6sk;
654
655 newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot);
656 if (!newsk)
657 goto out;
658
659 sock_init_data(NULL, newsk);
660
661 sctp_copy_sock(newsk, sk, asoc);
662 sock_reset_flag(sk, SOCK_ZAPPED);
663
664 newsctp6sk = (struct sctp6_sock *)newsk;
665 inet_sk(newsk)->pinet6 = &newsctp6sk->inet6;
666
667 sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped;
668
669 newnp = inet6_sk(newsk);
670
671 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
672
673 /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
674 * and getpeername().
675 */
676 sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
677
678 sk_refcnt_debug_inc(newsk);
679
680 if (newsk->sk_prot->init(newsk)) {
681 sk_common_release(newsk);
682 newsk = NULL;
683 }
684
685out:
686 return newsk;
687}
688
689/* Map v4 address to mapped v6 address */
690static void sctp_v6_addr_v4map(struct sctp_sock *sp, union sctp_addr *addr)
691{
692 if (sp->v4mapped && AF_INET == addr->sa.sa_family)
693 sctp_v4_map_v6(addr);
694}
695
696/* Where did this skb come from? */
697static int sctp_v6_skb_iif(const struct sk_buff *skb)
698{
699 struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb;
700 return opt->iif;
701}
702
703/* Was this packet marked by Explicit Congestion Notification? */
704static int sctp_v6_is_ce(const struct sk_buff *skb)
705{
706 return *((__u32 *)(ipv6_hdr(skb))) & htonl(1 << 20);
707}
708
709/* Dump the v6 addr to the seq file. */
710static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
711{
712 seq_printf(seq, "%pI6 ", &addr->v6.sin6_addr);
713}
714
715static void sctp_v6_ecn_capable(struct sock *sk)
716{
717 inet6_sk(sk)->tclass |= INET_ECN_ECT_0;
718}
719
720/* Initialize a PF_INET6 socket msg_name. */
721static void sctp_inet6_msgname(char *msgname, int *addr_len)
722{
723 struct sockaddr_in6 *sin6;
724
725 sin6 = (struct sockaddr_in6 *)msgname;
726 sin6->sin6_family = AF_INET6;
727 sin6->sin6_flowinfo = 0;
728 sin6->sin6_scope_id = 0; /*FIXME */
729 *addr_len = sizeof(struct sockaddr_in6);
730}
731
732/* Initialize a PF_INET msgname from a ulpevent. */
733static void sctp_inet6_event_msgname(struct sctp_ulpevent *event,
734 char *msgname, int *addrlen)
735{
736 struct sockaddr_in6 *sin6, *sin6from;
737
738 if (msgname) {
739 union sctp_addr *addr;
740 struct sctp_association *asoc;
741
742 asoc = event->asoc;
743 sctp_inet6_msgname(msgname, addrlen);
744 sin6 = (struct sockaddr_in6 *)msgname;
745 sin6->sin6_port = htons(asoc->peer.port);
746 addr = &asoc->peer.primary_addr;
747
748 /* Note: If we go to a common v6 format, this code
749 * will change.
750 */
751
752 /* Map ipv4 address into v4-mapped-on-v6 address. */
753 if (sctp_sk(asoc->base.sk)->v4mapped &&
754 AF_INET == addr->sa.sa_family) {
755 sctp_v4_map_v6((union sctp_addr *)sin6);
756 sin6->sin6_addr.s6_addr32[3] =
757 addr->v4.sin_addr.s_addr;
758 return;
759 }
760
761 sin6from = &asoc->peer.primary_addr.v6;
762 ipv6_addr_copy(&sin6->sin6_addr, &sin6from->sin6_addr);
763 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
764 sin6->sin6_scope_id = sin6from->sin6_scope_id;
765 }
766}
767
768/* Initialize a msg_name from an inbound skb. */
769static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname,
770 int *addr_len)
771{
772 struct sctphdr *sh;
773 struct sockaddr_in6 *sin6;
774
775 if (msgname) {
776 sctp_inet6_msgname(msgname, addr_len);
777 sin6 = (struct sockaddr_in6 *)msgname;
778 sh = sctp_hdr(skb);
779 sin6->sin6_port = sh->source;
780
781 /* Map ipv4 address into v4-mapped-on-v6 address. */
782 if (sctp_sk(skb->sk)->v4mapped &&
783 ip_hdr(skb)->version == 4) {
784 sctp_v4_map_v6((union sctp_addr *)sin6);
785 sin6->sin6_addr.s6_addr32[3] = ip_hdr(skb)->saddr;
786 return;
787 }
788
789 /* Otherwise, just copy the v6 address. */
790 ipv6_addr_copy(&sin6->sin6_addr, &ipv6_hdr(skb)->saddr);
791 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) {
792 struct sctp_ulpevent *ev = sctp_skb2event(skb);
793 sin6->sin6_scope_id = ev->iif;
794 }
795 }
796}
797
798/* Do we support this AF? */
799static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp)
800{
801 switch (family) {
802 case AF_INET6:
803 return 1;
804 /* v4-mapped-v6 addresses */
805 case AF_INET:
806 if (!__ipv6_only_sock(sctp_opt2sk(sp)))
807 return 1;
808 default:
809 return 0;
810 }
811}
812
813/* Address matching with wildcards allowed. This extra level
814 * of indirection lets us choose whether a PF_INET6 should
815 * disallow any v4 addresses if we so choose.
816 */
817static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
818 const union sctp_addr *addr2,
819 struct sctp_sock *opt)
820{
821 struct sctp_af *af1, *af2;
822 struct sock *sk = sctp_opt2sk(opt);
823
824 af1 = sctp_get_af_specific(addr1->sa.sa_family);
825 af2 = sctp_get_af_specific(addr2->sa.sa_family);
826
827 if (!af1 || !af2)
828 return 0;
829
830 /* If the socket is IPv6 only, v4 addrs will not match */
831 if (__ipv6_only_sock(sk) && af1 != af2)
832 return 0;
833
834 /* Today, wildcard AF_INET/AF_INET6. */
835 if (sctp_is_any(sk, addr1) || sctp_is_any(sk, addr2))
836 return 1;
837
838 if (addr1->sa.sa_family != addr2->sa.sa_family)
839 return 0;
840
841 return af1->cmp_addr(addr1, addr2);
842}
843
844/* Verify that the provided sockaddr looks bindable. Common verification,
845 * has already been taken care of.
846 */
847static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
848{
849 struct sctp_af *af;
850
851 /* ASSERT: address family has already been verified. */
852 if (addr->sa.sa_family != AF_INET6)
853 af = sctp_get_af_specific(addr->sa.sa_family);
854 else {
855 int type = ipv6_addr_type(&addr->v6.sin6_addr);
856 struct net_device *dev;
857
858 if (type & IPV6_ADDR_LINKLOCAL) {
859 if (!addr->v6.sin6_scope_id)
860 return 0;
861 rcu_read_lock();
862 dev = dev_get_by_index_rcu(&init_net,
863 addr->v6.sin6_scope_id);
864 if (!dev ||
865 !ipv6_chk_addr(&init_net, &addr->v6.sin6_addr,
866 dev, 0)) {
867 rcu_read_unlock();
868 return 0;
869 }
870 rcu_read_unlock();
871 } else if (type == IPV6_ADDR_MAPPED) {
872 if (!opt->v4mapped)
873 return 0;
874 }
875
876 af = opt->pf->af;
877 }
878 return af->available(addr, opt);
879}
880
881/* Verify that the provided sockaddr looks sendable. Common verification,
882 * has already been taken care of.
883 */
884static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
885{
886 struct sctp_af *af = NULL;
887
888 /* ASSERT: address family has already been verified. */
889 if (addr->sa.sa_family != AF_INET6)
890 af = sctp_get_af_specific(addr->sa.sa_family);
891 else {
892 int type = ipv6_addr_type(&addr->v6.sin6_addr);
893 struct net_device *dev;
894
895 if (type & IPV6_ADDR_LINKLOCAL) {
896 if (!addr->v6.sin6_scope_id)
897 return 0;
898 rcu_read_lock();
899 dev = dev_get_by_index_rcu(&init_net,
900 addr->v6.sin6_scope_id);
901 rcu_read_unlock();
902 if (!dev)
903 return 0;
904 }
905 af = opt->pf->af;
906 }
907
908 return af != NULL;
909}
910
911/* Fill in Supported Address Type information for INIT and INIT-ACK
912 * chunks. Note: In the future, we may want to look at sock options
913 * to determine whether a PF_INET6 socket really wants to have IPV4
914 * addresses.
915 * Returns number of addresses supported.
916 */
917static int sctp_inet6_supported_addrs(const struct sctp_sock *opt,
918 __be16 *types)
919{
920 types[0] = SCTP_PARAM_IPV6_ADDRESS;
921 if (!opt || !ipv6_only_sock(sctp_opt2sk(opt))) {
922 types[1] = SCTP_PARAM_IPV4_ADDRESS;
923 return 2;
924 }
925 return 1;
926}
927
928static const struct proto_ops inet6_seqpacket_ops = {
929 .family = PF_INET6,
930 .owner = THIS_MODULE,
931 .release = inet6_release,
932 .bind = inet6_bind,
933 .connect = inet_dgram_connect,
934 .socketpair = sock_no_socketpair,
935 .accept = inet_accept,
936 .getname = inet6_getname,
937 .poll = sctp_poll,
938 .ioctl = inet6_ioctl,
939 .listen = sctp_inet_listen,
940 .shutdown = inet_shutdown,
941 .setsockopt = sock_common_setsockopt,
942 .getsockopt = sock_common_getsockopt,
943 .sendmsg = inet_sendmsg,
944 .recvmsg = sock_common_recvmsg,
945 .mmap = sock_no_mmap,
946#ifdef CONFIG_COMPAT
947 .compat_setsockopt = compat_sock_common_setsockopt,
948 .compat_getsockopt = compat_sock_common_getsockopt,
949#endif
950};
951
952static struct inet_protosw sctpv6_seqpacket_protosw = {
953 .type = SOCK_SEQPACKET,
954 .protocol = IPPROTO_SCTP,
955 .prot = &sctpv6_prot,
956 .ops = &inet6_seqpacket_ops,
957 .no_check = 0,
958 .flags = SCTP_PROTOSW_FLAG
959};
960static struct inet_protosw sctpv6_stream_protosw = {
961 .type = SOCK_STREAM,
962 .protocol = IPPROTO_SCTP,
963 .prot = &sctpv6_prot,
964 .ops = &inet6_seqpacket_ops,
965 .no_check = 0,
966 .flags = SCTP_PROTOSW_FLAG,
967};
968
969static int sctp6_rcv(struct sk_buff *skb)
970{
971 return sctp_rcv(skb) ? -1 : 0;
972}
973
974static const struct inet6_protocol sctpv6_protocol = {
975 .handler = sctp6_rcv,
976 .err_handler = sctp_v6_err,
977 .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
978};
979
980static struct sctp_af sctp_af_inet6 = {
981 .sa_family = AF_INET6,
982 .sctp_xmit = sctp_v6_xmit,
983 .setsockopt = ipv6_setsockopt,
984 .getsockopt = ipv6_getsockopt,
985 .get_dst = sctp_v6_get_dst,
986 .get_saddr = sctp_v6_get_saddr,
987 .copy_addrlist = sctp_v6_copy_addrlist,
988 .from_skb = sctp_v6_from_skb,
989 .from_sk = sctp_v6_from_sk,
990 .to_sk_saddr = sctp_v6_to_sk_saddr,
991 .to_sk_daddr = sctp_v6_to_sk_daddr,
992 .from_addr_param = sctp_v6_from_addr_param,
993 .to_addr_param = sctp_v6_to_addr_param,
994 .cmp_addr = sctp_v6_cmp_addr,
995 .scope = sctp_v6_scope,
996 .addr_valid = sctp_v6_addr_valid,
997 .inaddr_any = sctp_v6_inaddr_any,
998 .is_any = sctp_v6_is_any,
999 .available = sctp_v6_available,
1000 .skb_iif = sctp_v6_skb_iif,
1001 .is_ce = sctp_v6_is_ce,
1002 .seq_dump_addr = sctp_v6_seq_dump_addr,
1003 .ecn_capable = sctp_v6_ecn_capable,
1004 .net_header_len = sizeof(struct ipv6hdr),
1005 .sockaddr_len = sizeof(struct sockaddr_in6),
1006#ifdef CONFIG_COMPAT
1007 .compat_setsockopt = compat_ipv6_setsockopt,
1008 .compat_getsockopt = compat_ipv6_getsockopt,
1009#endif
1010};
1011
1012static struct sctp_pf sctp_pf_inet6 = {
1013 .event_msgname = sctp_inet6_event_msgname,
1014 .skb_msgname = sctp_inet6_skb_msgname,
1015 .af_supported = sctp_inet6_af_supported,
1016 .cmp_addr = sctp_inet6_cmp_addr,
1017 .bind_verify = sctp_inet6_bind_verify,
1018 .send_verify = sctp_inet6_send_verify,
1019 .supported_addrs = sctp_inet6_supported_addrs,
1020 .create_accept_sk = sctp_v6_create_accept_sk,
1021 .addr_v4map = sctp_v6_addr_v4map,
1022 .af = &sctp_af_inet6,
1023};
1024
1025/* Initialize IPv6 support and register with socket layer. */
1026void sctp_v6_pf_init(void)
1027{
1028 /* Register the SCTP specific PF_INET6 functions. */
1029 sctp_register_pf(&sctp_pf_inet6, PF_INET6);
1030
1031 /* Register the SCTP specific AF_INET6 functions. */
1032 sctp_register_af(&sctp_af_inet6);
1033}
1034
1035void sctp_v6_pf_exit(void)
1036{
1037 list_del(&sctp_af_inet6.list);
1038}
1039
1040/* Initialize IPv6 support and register with socket layer. */
1041int sctp_v6_protosw_init(void)
1042{
1043 int rc;
1044
1045 rc = proto_register(&sctpv6_prot, 1);
1046 if (rc)
1047 return rc;
1048
1049 /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
1050 inet6_register_protosw(&sctpv6_seqpacket_protosw);
1051 inet6_register_protosw(&sctpv6_stream_protosw);
1052
1053 return 0;
1054}
1055
1056void sctp_v6_protosw_exit(void)
1057{
1058 inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
1059 inet6_unregister_protosw(&sctpv6_stream_protosw);
1060 proto_unregister(&sctpv6_prot);
1061}
1062
1063
1064/* Register with inet6 layer. */
1065int sctp_v6_add_protocol(void)
1066{
1067 /* Register notifier for inet6 address additions/deletions. */
1068 register_inet6addr_notifier(&sctp_inet6addr_notifier);
1069
1070 if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
1071 return -EAGAIN;
1072
1073 return 0;
1074}
1075
1076/* Unregister with inet6 layer. */
1077void sctp_v6_del_protocol(void)
1078{
1079 inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
1080 unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
1081}
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 found = 1;
107 addr->valid = 0;
108 list_del_rcu(&addr->list);
109 sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_DEL);
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 = dst_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, res, bound_dev_if;
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 rcu_read_lock();
701 bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
702 if (bound_dev_if) {
703 res = 0;
704 dev = dev_get_by_index_rcu(net, bound_dev_if);
705 if (!dev)
706 goto out;
707 }
708
709 res = ipv6_can_nonlocal_bind(net, &sp->inet) ||
710 ipv6_chk_addr(net, in6, dev, 0);
711
712out:
713 rcu_read_unlock();
714 return res;
715}
716
717/* This function checks if the address is a valid address to be used for
718 * SCTP.
719 *
720 * Output:
721 * Return 0 - If the address is a non-unicast or an illegal address.
722 * Return 1 - If the address is a unicast.
723 */
724static int sctp_v6_addr_valid(union sctp_addr *addr,
725 struct sctp_sock *sp,
726 const struct sk_buff *skb)
727{
728 int ret = ipv6_addr_type(&addr->v6.sin6_addr);
729
730 /* Support v4-mapped-v6 address. */
731 if (ret == IPV6_ADDR_MAPPED) {
732 /* Note: This routine is used in input, so v4-mapped-v6
733 * are disallowed here when there is no sctp_sock.
734 */
735 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
736 return 0;
737 sctp_v6_map_v4(addr);
738 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb);
739 }
740
741 /* Is this a non-unicast address */
742 if (!(ret & IPV6_ADDR_UNICAST))
743 return 0;
744
745 return 1;
746}
747
748/* What is the scope of 'addr'? */
749static enum sctp_scope sctp_v6_scope(union sctp_addr *addr)
750{
751 enum sctp_scope retval;
752 int v6scope;
753
754 /* The IPv6 scope is really a set of bit fields.
755 * See IFA_* in <net/if_inet6.h>. Map to a generic SCTP scope.
756 */
757
758 v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
759 switch (v6scope) {
760 case IFA_HOST:
761 retval = SCTP_SCOPE_LOOPBACK;
762 break;
763 case IFA_LINK:
764 retval = SCTP_SCOPE_LINK;
765 break;
766 case IFA_SITE:
767 retval = SCTP_SCOPE_PRIVATE;
768 break;
769 default:
770 retval = SCTP_SCOPE_GLOBAL;
771 break;
772 }
773
774 return retval;
775}
776
777/* Create and initialize a new sk for the socket to be returned by accept(). */
778static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
779 struct sctp_association *asoc,
780 bool kern)
781{
782 struct sock *newsk;
783 struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
784 struct sctp6_sock *newsctp6sk;
785
786 newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot, kern);
787 if (!newsk)
788 goto out;
789
790 sock_init_data(NULL, newsk);
791
792 sctp_copy_sock(newsk, sk, asoc);
793 sock_reset_flag(sk, SOCK_ZAPPED);
794
795 newsctp6sk = (struct sctp6_sock *)newsk;
796 inet_sk(newsk)->pinet6 = &newsctp6sk->inet6;
797
798 sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped;
799
800 newnp = inet6_sk(newsk);
801
802 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
803 newnp->ipv6_mc_list = NULL;
804 newnp->ipv6_ac_list = NULL;
805 newnp->ipv6_fl_list = NULL;
806
807 sctp_v6_copy_ip_options(sk, newsk);
808
809 /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
810 * and getpeername().
811 */
812 sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
813
814 newsk->sk_v6_rcv_saddr = sk->sk_v6_rcv_saddr;
815
816 if (newsk->sk_prot->init(newsk)) {
817 sk_common_release(newsk);
818 newsk = NULL;
819 }
820
821out:
822 return newsk;
823}
824
825/* Format a sockaddr for return to user space. This makes sure the return is
826 * AF_INET or AF_INET6 depending on the SCTP_I_WANT_MAPPED_V4_ADDR option.
827 */
828static int sctp_v6_addr_to_user(struct sctp_sock *sp, union sctp_addr *addr)
829{
830 if (sp->v4mapped) {
831 if (addr->sa.sa_family == AF_INET)
832 sctp_v4_map_v6(addr);
833 } else {
834 if (addr->sa.sa_family == AF_INET6 &&
835 ipv6_addr_v4mapped(&addr->v6.sin6_addr))
836 sctp_v6_map_v4(addr);
837 }
838
839 if (addr->sa.sa_family == AF_INET) {
840 memset(addr->v4.sin_zero, 0, sizeof(addr->v4.sin_zero));
841 return sizeof(struct sockaddr_in);
842 }
843 return sizeof(struct sockaddr_in6);
844}
845
846/* Where did this skb come from? */
847static int sctp_v6_skb_iif(const struct sk_buff *skb)
848{
849 return inet6_iif(skb);
850}
851
852static int sctp_v6_skb_sdif(const struct sk_buff *skb)
853{
854 return inet6_sdif(skb);
855}
856
857/* Was this packet marked by Explicit Congestion Notification? */
858static int sctp_v6_is_ce(const struct sk_buff *skb)
859{
860 return *((__u32 *)(ipv6_hdr(skb))) & (__force __u32)htonl(1 << 20);
861}
862
863/* Dump the v6 addr to the seq file. */
864static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
865{
866 seq_printf(seq, "%pI6 ", &addr->v6.sin6_addr);
867}
868
869static void sctp_v6_ecn_capable(struct sock *sk)
870{
871 inet6_sk(sk)->tclass |= INET_ECN_ECT_0;
872}
873
874/* Initialize a PF_INET msgname from a ulpevent. */
875static void sctp_inet6_event_msgname(struct sctp_ulpevent *event,
876 char *msgname, int *addrlen)
877{
878 union sctp_addr *addr;
879 struct sctp_association *asoc;
880 union sctp_addr *paddr;
881
882 if (!msgname)
883 return;
884
885 addr = (union sctp_addr *)msgname;
886 asoc = event->asoc;
887 paddr = &asoc->peer.primary_addr;
888
889 if (paddr->sa.sa_family == AF_INET) {
890 addr->v4.sin_family = AF_INET;
891 addr->v4.sin_port = htons(asoc->peer.port);
892 addr->v4.sin_addr = paddr->v4.sin_addr;
893 } else {
894 addr->v6.sin6_family = AF_INET6;
895 addr->v6.sin6_flowinfo = 0;
896 if (ipv6_addr_type(&paddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
897 addr->v6.sin6_scope_id = paddr->v6.sin6_scope_id;
898 else
899 addr->v6.sin6_scope_id = 0;
900 addr->v6.sin6_port = htons(asoc->peer.port);
901 addr->v6.sin6_addr = paddr->v6.sin6_addr;
902 }
903
904 *addrlen = sctp_v6_addr_to_user(sctp_sk(asoc->base.sk), addr);
905}
906
907/* Initialize a msg_name from an inbound skb. */
908static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname,
909 int *addr_len)
910{
911 union sctp_addr *addr;
912 struct sctphdr *sh;
913
914 if (!msgname)
915 return;
916
917 addr = (union sctp_addr *)msgname;
918 sh = sctp_hdr(skb);
919
920 if (ip_hdr(skb)->version == 4) {
921 addr->v4.sin_family = AF_INET;
922 addr->v4.sin_port = sh->source;
923 addr->v4.sin_addr.s_addr = ip_hdr(skb)->saddr;
924 } else {
925 addr->v6.sin6_family = AF_INET6;
926 addr->v6.sin6_flowinfo = 0;
927 addr->v6.sin6_port = sh->source;
928 addr->v6.sin6_addr = ipv6_hdr(skb)->saddr;
929 if (ipv6_addr_type(&addr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
930 addr->v6.sin6_scope_id = sctp_v6_skb_iif(skb);
931 else
932 addr->v6.sin6_scope_id = 0;
933 }
934
935 *addr_len = sctp_v6_addr_to_user(sctp_sk(skb->sk), addr);
936}
937
938/* Do we support this AF? */
939static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp)
940{
941 switch (family) {
942 case AF_INET6:
943 return 1;
944 /* v4-mapped-v6 addresses */
945 case AF_INET:
946 if (!ipv6_only_sock(sctp_opt2sk(sp)))
947 return 1;
948 fallthrough;
949 default:
950 return 0;
951 }
952}
953
954/* Address matching with wildcards allowed. This extra level
955 * of indirection lets us choose whether a PF_INET6 should
956 * disallow any v4 addresses if we so choose.
957 */
958static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
959 const union sctp_addr *addr2,
960 struct sctp_sock *opt)
961{
962 struct sock *sk = sctp_opt2sk(opt);
963 struct sctp_af *af1, *af2;
964
965 af1 = sctp_get_af_specific(addr1->sa.sa_family);
966 af2 = sctp_get_af_specific(addr2->sa.sa_family);
967
968 if (!af1 || !af2)
969 return 0;
970
971 /* If the socket is IPv6 only, v4 addrs will not match */
972 if (ipv6_only_sock(sk) && af1 != af2)
973 return 0;
974
975 /* Today, wildcard AF_INET/AF_INET6. */
976 if (sctp_is_any(sk, addr1) || sctp_is_any(sk, addr2))
977 return 1;
978
979 if (addr1->sa.sa_family == AF_INET && addr2->sa.sa_family == AF_INET)
980 return addr1->v4.sin_addr.s_addr == addr2->v4.sin_addr.s_addr;
981
982 return __sctp_v6_cmp_addr(addr1, addr2);
983}
984
985/* Verify that the provided sockaddr looks bindable. Common verification,
986 * has already been taken care of.
987 */
988static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
989{
990 struct sctp_af *af;
991
992 /* ASSERT: address family has already been verified. */
993 if (addr->sa.sa_family != AF_INET6)
994 af = sctp_get_af_specific(addr->sa.sa_family);
995 else {
996 int type = ipv6_addr_type(&addr->v6.sin6_addr);
997 struct net_device *dev;
998
999 if (type & IPV6_ADDR_LINKLOCAL) {
1000 struct net *net;
1001 if (!addr->v6.sin6_scope_id)
1002 return 0;
1003 net = sock_net(&opt->inet.sk);
1004 rcu_read_lock();
1005 dev = dev_get_by_index_rcu(net, addr->v6.sin6_scope_id);
1006 if (!dev || !(ipv6_can_nonlocal_bind(net, &opt->inet) ||
1007 ipv6_chk_addr(net, &addr->v6.sin6_addr,
1008 dev, 0))) {
1009 rcu_read_unlock();
1010 return 0;
1011 }
1012 rcu_read_unlock();
1013 }
1014
1015 af = opt->pf->af;
1016 }
1017 return af->available(addr, opt);
1018}
1019
1020/* Verify that the provided sockaddr looks sendable. Common verification,
1021 * has already been taken care of.
1022 */
1023static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
1024{
1025 struct sctp_af *af = NULL;
1026
1027 /* ASSERT: address family has already been verified. */
1028 if (addr->sa.sa_family != AF_INET6)
1029 af = sctp_get_af_specific(addr->sa.sa_family);
1030 else {
1031 int type = ipv6_addr_type(&addr->v6.sin6_addr);
1032 struct net_device *dev;
1033
1034 if (type & IPV6_ADDR_LINKLOCAL) {
1035 if (!addr->v6.sin6_scope_id)
1036 return 0;
1037 rcu_read_lock();
1038 dev = dev_get_by_index_rcu(sock_net(&opt->inet.sk),
1039 addr->v6.sin6_scope_id);
1040 rcu_read_unlock();
1041 if (!dev)
1042 return 0;
1043 }
1044 af = opt->pf->af;
1045 }
1046
1047 return af != NULL;
1048}
1049
1050/* Fill in Supported Address Type information for INIT and INIT-ACK
1051 * chunks. Note: In the future, we may want to look at sock options
1052 * to determine whether a PF_INET6 socket really wants to have IPV4
1053 * addresses.
1054 * Returns number of addresses supported.
1055 */
1056static int sctp_inet6_supported_addrs(const struct sctp_sock *opt,
1057 __be16 *types)
1058{
1059 types[0] = SCTP_PARAM_IPV6_ADDRESS;
1060 if (!opt || !ipv6_only_sock(sctp_opt2sk(opt))) {
1061 types[1] = SCTP_PARAM_IPV4_ADDRESS;
1062 return 2;
1063 }
1064 return 1;
1065}
1066
1067/* Handle SCTP_I_WANT_MAPPED_V4_ADDR for getpeername() and getsockname() */
1068static int sctp_getname(struct socket *sock, struct sockaddr *uaddr,
1069 int peer)
1070{
1071 int rc;
1072
1073 rc = inet6_getname(sock, uaddr, peer);
1074
1075 if (rc < 0)
1076 return rc;
1077
1078 rc = sctp_v6_addr_to_user(sctp_sk(sock->sk),
1079 (union sctp_addr *)uaddr);
1080
1081 return rc;
1082}
1083
1084static const struct proto_ops inet6_seqpacket_ops = {
1085 .family = PF_INET6,
1086 .owner = THIS_MODULE,
1087 .release = inet6_release,
1088 .bind = inet6_bind,
1089 .connect = sctp_inet_connect,
1090 .socketpair = sock_no_socketpair,
1091 .accept = inet_accept,
1092 .getname = sctp_getname,
1093 .poll = sctp_poll,
1094 .ioctl = inet6_ioctl,
1095 .gettstamp = sock_gettstamp,
1096 .listen = sctp_inet_listen,
1097 .shutdown = inet_shutdown,
1098 .setsockopt = sock_common_setsockopt,
1099 .getsockopt = sock_common_getsockopt,
1100 .sendmsg = inet_sendmsg,
1101 .recvmsg = inet_recvmsg,
1102 .mmap = sock_no_mmap,
1103#ifdef CONFIG_COMPAT
1104 .compat_ioctl = inet6_compat_ioctl,
1105#endif
1106};
1107
1108static struct inet_protosw sctpv6_seqpacket_protosw = {
1109 .type = SOCK_SEQPACKET,
1110 .protocol = IPPROTO_SCTP,
1111 .prot = &sctpv6_prot,
1112 .ops = &inet6_seqpacket_ops,
1113 .flags = SCTP_PROTOSW_FLAG
1114};
1115static struct inet_protosw sctpv6_stream_protosw = {
1116 .type = SOCK_STREAM,
1117 .protocol = IPPROTO_SCTP,
1118 .prot = &sctpv6_prot,
1119 .ops = &inet6_seqpacket_ops,
1120 .flags = SCTP_PROTOSW_FLAG,
1121};
1122
1123static int sctp6_rcv(struct sk_buff *skb)
1124{
1125 SCTP_INPUT_CB(skb)->encap_port = 0;
1126 return sctp_rcv(skb) ? -1 : 0;
1127}
1128
1129static const struct inet6_protocol sctpv6_protocol = {
1130 .handler = sctp6_rcv,
1131 .err_handler = sctp_v6_err,
1132 .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
1133};
1134
1135static struct sctp_af sctp_af_inet6 = {
1136 .sa_family = AF_INET6,
1137 .sctp_xmit = sctp_v6_xmit,
1138 .setsockopt = ipv6_setsockopt,
1139 .getsockopt = ipv6_getsockopt,
1140 .get_dst = sctp_v6_get_dst,
1141 .get_saddr = sctp_v6_get_saddr,
1142 .copy_addrlist = sctp_v6_copy_addrlist,
1143 .from_skb = sctp_v6_from_skb,
1144 .from_sk = sctp_v6_from_sk,
1145 .from_addr_param = sctp_v6_from_addr_param,
1146 .to_addr_param = sctp_v6_to_addr_param,
1147 .cmp_addr = sctp_v6_cmp_addr,
1148 .scope = sctp_v6_scope,
1149 .addr_valid = sctp_v6_addr_valid,
1150 .inaddr_any = sctp_v6_inaddr_any,
1151 .is_any = sctp_v6_is_any,
1152 .available = sctp_v6_available,
1153 .skb_iif = sctp_v6_skb_iif,
1154 .skb_sdif = sctp_v6_skb_sdif,
1155 .is_ce = sctp_v6_is_ce,
1156 .seq_dump_addr = sctp_v6_seq_dump_addr,
1157 .ecn_capable = sctp_v6_ecn_capable,
1158 .net_header_len = sizeof(struct ipv6hdr),
1159 .sockaddr_len = sizeof(struct sockaddr_in6),
1160 .ip_options_len = sctp_v6_ip_options_len,
1161};
1162
1163static struct sctp_pf sctp_pf_inet6 = {
1164 .event_msgname = sctp_inet6_event_msgname,
1165 .skb_msgname = sctp_inet6_skb_msgname,
1166 .af_supported = sctp_inet6_af_supported,
1167 .cmp_addr = sctp_inet6_cmp_addr,
1168 .bind_verify = sctp_inet6_bind_verify,
1169 .send_verify = sctp_inet6_send_verify,
1170 .supported_addrs = sctp_inet6_supported_addrs,
1171 .create_accept_sk = sctp_v6_create_accept_sk,
1172 .addr_to_user = sctp_v6_addr_to_user,
1173 .to_sk_saddr = sctp_v6_to_sk_saddr,
1174 .to_sk_daddr = sctp_v6_to_sk_daddr,
1175 .copy_ip_options = sctp_v6_copy_ip_options,
1176 .af = &sctp_af_inet6,
1177};
1178
1179/* Initialize IPv6 support and register with socket layer. */
1180void sctp_v6_pf_init(void)
1181{
1182 /* Register the SCTP specific PF_INET6 functions. */
1183 sctp_register_pf(&sctp_pf_inet6, PF_INET6);
1184
1185 /* Register the SCTP specific AF_INET6 functions. */
1186 sctp_register_af(&sctp_af_inet6);
1187}
1188
1189void sctp_v6_pf_exit(void)
1190{
1191 list_del(&sctp_af_inet6.list);
1192}
1193
1194/* Initialize IPv6 support and register with socket layer. */
1195int sctp_v6_protosw_init(void)
1196{
1197 int rc;
1198
1199 rc = proto_register(&sctpv6_prot, 1);
1200 if (rc)
1201 return rc;
1202
1203 /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
1204 inet6_register_protosw(&sctpv6_seqpacket_protosw);
1205 inet6_register_protosw(&sctpv6_stream_protosw);
1206
1207 return 0;
1208}
1209
1210void sctp_v6_protosw_exit(void)
1211{
1212 inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
1213 inet6_unregister_protosw(&sctpv6_stream_protosw);
1214 proto_unregister(&sctpv6_prot);
1215}
1216
1217
1218/* Register with inet6 layer. */
1219int sctp_v6_add_protocol(void)
1220{
1221 /* Register notifier for inet6 address additions/deletions. */
1222 register_inet6addr_notifier(&sctp_inet6addr_notifier);
1223
1224 if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
1225 return -EAGAIN;
1226
1227 return 0;
1228}
1229
1230/* Unregister with inet6 layer. */
1231void sctp_v6_del_protocol(void)
1232{
1233 inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
1234 unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
1235}