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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#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}