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