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