xref: /linux/net/sctp/ipv6.c (revision 9c736ace0666efe68efd53fcdfa2c6653c3e0e72)
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 
62 static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
63 					 union sctp_addr *s2);
64 static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr,
65 			      __be16 port);
66 static 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  */
sctp_inet6addr_event(struct notifier_block * this,unsigned long ev,void * ptr)75 static 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 
122 static struct notifier_block sctp_inet6addr_notifier = {
123 	.notifier_call = sctp_inet6addr_event,
124 };
125 
sctp_v6_err_handle(struct sctp_transport * t,struct sk_buff * skb,__u8 type,__u8 code,__u32 info)126 static 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. */
sctp_v6_err(struct sk_buff * skb,struct inet6_skb_parm * opt,u8 type,u8 code,int offset,__be32 info)161 static 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 
sctp_udp_v6_err(struct sock * sk,struct sk_buff * skb)190 int 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 
sctp_v6_xmit(struct sk_buff * skb,struct sctp_transport * t)220 static 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 	udp_tunnel6_xmit_skb(dst, sk, skb, NULL, &fl6->saddr, &fl6->daddr,
265 			     tclass, ip6_dst_hoplimit(dst), label,
266 			     sctp_sk(sk)->udp_port, t->encap_port, false, 0);
267 	return 0;
268 }
269 
270 /* Returns the dst cache entry for the given source and destination ip
271  * addresses.
272  */
sctp_v6_get_dst(struct sctp_transport * t,union sctp_addr * saddr,struct flowi * fl,struct sock * sk)273 static void sctp_v6_get_dst(struct sctp_transport *t, union sctp_addr *saddr,
274 			    struct flowi *fl, struct sock *sk)
275 {
276 	struct sctp_association *asoc = t->asoc;
277 	struct dst_entry *dst = NULL;
278 	struct flowi _fl;
279 	struct flowi6 *fl6 = &_fl.u.ip6;
280 	struct sctp_bind_addr *bp;
281 	struct ipv6_pinfo *np = inet6_sk(sk);
282 	struct sctp_sockaddr_entry *laddr;
283 	union sctp_addr *daddr = &t->ipaddr;
284 	union sctp_addr dst_saddr;
285 	struct in6_addr *final_p, final;
286 	enum sctp_scope scope;
287 	__u8 matchlen = 0;
288 
289 	memset(&_fl, 0, sizeof(_fl));
290 	fl6->daddr = daddr->v6.sin6_addr;
291 	fl6->fl6_dport = daddr->v6.sin6_port;
292 	fl6->flowi6_proto = IPPROTO_SCTP;
293 	if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
294 		fl6->flowi6_oif = daddr->v6.sin6_scope_id;
295 	else if (asoc)
296 		fl6->flowi6_oif = asoc->base.sk->sk_bound_dev_if;
297 	if (t->flowlabel & SCTP_FLOWLABEL_SET_MASK)
298 		fl6->flowlabel = htonl(t->flowlabel & SCTP_FLOWLABEL_VAL_MASK);
299 
300 	if (inet6_test_bit(SNDFLOW, sk) &&
301 	    (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 
415 out:
416 	if (!IS_ERR_OR_NULL(dst)) {
417 		struct rt6_info *rt;
418 
419 		rt = dst_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  */
sctp_v6_addr_match_len(union sctp_addr * s1,union sctp_addr * s2)433 static 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  */
sctp_v6_get_saddr(struct sctp_sock * sk,struct sctp_transport * t,struct flowi * fl)442 static 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. */
sctp_v6_copy_addrlist(struct list_head * addrlist,struct net_device * dev)458 static 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 */
sctp_v6_copy_ip_options(struct sock * sk,struct sock * newsk)490 static 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 */
sctp_v6_ip_options_len(struct sock * sk)509 static 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. */
sctp_v6_from_skb(union sctp_addr * addr,struct sk_buff * skb,int is_saddr)525 static 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. */
sctp_v6_from_sk(union sctp_addr * addr,struct sock * sk)546 static 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_flowinfo = 0;
551 	addr->v6.sin6_addr = sk->sk_v6_rcv_saddr;
552 	addr->v6.sin6_scope_id = 0;
553 }
554 
555 /* Initialize sk->sk_rcv_saddr from sctp_addr. */
sctp_v6_to_sk_saddr(union sctp_addr * addr,struct sock * sk)556 static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
557 {
558 	if (addr->sa.sa_family == AF_INET) {
559 		sk->sk_v6_rcv_saddr.s6_addr32[0] = 0;
560 		sk->sk_v6_rcv_saddr.s6_addr32[1] = 0;
561 		sk->sk_v6_rcv_saddr.s6_addr32[2] = htonl(0x0000ffff);
562 		sk->sk_v6_rcv_saddr.s6_addr32[3] =
563 			addr->v4.sin_addr.s_addr;
564 	} else {
565 		sk->sk_v6_rcv_saddr = addr->v6.sin6_addr;
566 	}
567 }
568 
569 /* Initialize sk->sk_daddr from sctp_addr. */
sctp_v6_to_sk_daddr(union sctp_addr * addr,struct sock * sk)570 static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
571 {
572 	if (addr->sa.sa_family == AF_INET) {
573 		sk->sk_v6_daddr.s6_addr32[0] = 0;
574 		sk->sk_v6_daddr.s6_addr32[1] = 0;
575 		sk->sk_v6_daddr.s6_addr32[2] = htonl(0x0000ffff);
576 		sk->sk_v6_daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
577 	} else {
578 		sk->sk_v6_daddr = addr->v6.sin6_addr;
579 	}
580 }
581 
582 /* Initialize a sctp_addr from an address parameter. */
sctp_v6_from_addr_param(union sctp_addr * addr,union sctp_addr_param * param,__be16 port,int iif)583 static bool sctp_v6_from_addr_param(union sctp_addr *addr,
584 				    union sctp_addr_param *param,
585 				    __be16 port, int iif)
586 {
587 	if (ntohs(param->v6.param_hdr.length) < sizeof(struct sctp_ipv6addr_param))
588 		return false;
589 
590 	addr->v6.sin6_family = AF_INET6;
591 	addr->v6.sin6_port = port;
592 	addr->v6.sin6_flowinfo = 0; /* BUG */
593 	addr->v6.sin6_addr = param->v6.addr;
594 	addr->v6.sin6_scope_id = iif;
595 
596 	return true;
597 }
598 
599 /* Initialize an address parameter from a sctp_addr and return the length
600  * of the address parameter.
601  */
sctp_v6_to_addr_param(const union sctp_addr * addr,union sctp_addr_param * param)602 static int sctp_v6_to_addr_param(const union sctp_addr *addr,
603 				 union sctp_addr_param *param)
604 {
605 	int length = sizeof(struct sctp_ipv6addr_param);
606 
607 	param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS;
608 	param->v6.param_hdr.length = htons(length);
609 	param->v6.addr = addr->v6.sin6_addr;
610 
611 	return length;
612 }
613 
614 /* Initialize a sctp_addr from struct in6_addr. */
sctp_v6_to_addr(union sctp_addr * addr,struct in6_addr * saddr,__be16 port)615 static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr,
616 			      __be16 port)
617 {
618 	addr->sa.sa_family = AF_INET6;
619 	addr->v6.sin6_port = port;
620 	addr->v6.sin6_flowinfo = 0;
621 	addr->v6.sin6_addr = *saddr;
622 	addr->v6.sin6_scope_id = 0;
623 }
624 
__sctp_v6_cmp_addr(const union sctp_addr * addr1,const union sctp_addr * addr2)625 static int __sctp_v6_cmp_addr(const union sctp_addr *addr1,
626 			      const union sctp_addr *addr2)
627 {
628 	if (addr1->sa.sa_family != addr2->sa.sa_family) {
629 		if (addr1->sa.sa_family == AF_INET &&
630 		    addr2->sa.sa_family == AF_INET6 &&
631 		    ipv6_addr_v4mapped(&addr2->v6.sin6_addr) &&
632 		    addr2->v6.sin6_addr.s6_addr32[3] ==
633 		    addr1->v4.sin_addr.s_addr)
634 			return 1;
635 
636 		if (addr2->sa.sa_family == AF_INET &&
637 		    addr1->sa.sa_family == AF_INET6 &&
638 		    ipv6_addr_v4mapped(&addr1->v6.sin6_addr) &&
639 		    addr1->v6.sin6_addr.s6_addr32[3] ==
640 		    addr2->v4.sin_addr.s_addr)
641 			return 1;
642 
643 		return 0;
644 	}
645 
646 	if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))
647 		return 0;
648 
649 	/* If this is a linklocal address, compare the scope_id. */
650 	if ((ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) &&
651 	    addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&
652 	    addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)
653 		return 0;
654 
655 	return 1;
656 }
657 
658 /* Compare addresses exactly.
659  * v4-mapped-v6 is also in consideration.
660  */
sctp_v6_cmp_addr(const union sctp_addr * addr1,const union sctp_addr * addr2)661 static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
662 			    const union sctp_addr *addr2)
663 {
664 	return __sctp_v6_cmp_addr(addr1, addr2) &&
665 	       addr1->v6.sin6_port == addr2->v6.sin6_port;
666 }
667 
668 /* Initialize addr struct to INADDR_ANY. */
sctp_v6_inaddr_any(union sctp_addr * addr,__be16 port)669 static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port)
670 {
671 	memset(addr, 0x00, sizeof(union sctp_addr));
672 	addr->v6.sin6_family = AF_INET6;
673 	addr->v6.sin6_port = port;
674 }
675 
676 /* Is this a wildcard address? */
sctp_v6_is_any(const union sctp_addr * addr)677 static int sctp_v6_is_any(const union sctp_addr *addr)
678 {
679 	return ipv6_addr_any(&addr->v6.sin6_addr);
680 }
681 
682 /* Should this be available for binding?   */
sctp_v6_available(union sctp_addr * addr,struct sctp_sock * sp)683 static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp)
684 {
685 	const struct in6_addr *in6 = (const struct in6_addr *)&addr->v6.sin6_addr;
686 	struct sock *sk = &sp->inet.sk;
687 	struct net *net = sock_net(sk);
688 	struct net_device *dev = NULL;
689 	int type, res, bound_dev_if;
690 
691 	type = ipv6_addr_type(in6);
692 	if (IPV6_ADDR_ANY == type)
693 		return 1;
694 	if (type == IPV6_ADDR_MAPPED) {
695 		if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
696 			return 0;
697 		sctp_v6_map_v4(addr);
698 		return sctp_get_af_specific(AF_INET)->available(addr, sp);
699 	}
700 	if (!(type & IPV6_ADDR_UNICAST))
701 		return 0;
702 
703 	rcu_read_lock();
704 	bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
705 	if (bound_dev_if) {
706 		res = 0;
707 		dev = dev_get_by_index_rcu(net, bound_dev_if);
708 		if (!dev)
709 			goto out;
710 	}
711 
712 	res = ipv6_can_nonlocal_bind(net, &sp->inet) ||
713 	      ipv6_chk_addr(net, in6, dev, 0);
714 
715 out:
716 	rcu_read_unlock();
717 	return res;
718 }
719 
720 /* This function checks if the address is a valid address to be used for
721  * SCTP.
722  *
723  * Output:
724  * Return 0 - If the address is a non-unicast or an illegal address.
725  * Return 1 - If the address is a unicast.
726  */
sctp_v6_addr_valid(union sctp_addr * addr,struct sctp_sock * sp,const struct sk_buff * skb)727 static int sctp_v6_addr_valid(union sctp_addr *addr,
728 			      struct sctp_sock *sp,
729 			      const struct sk_buff *skb)
730 {
731 	int ret = ipv6_addr_type(&addr->v6.sin6_addr);
732 
733 	/* Support v4-mapped-v6 address. */
734 	if (ret == IPV6_ADDR_MAPPED) {
735 		/* Note: This routine is used in input, so v4-mapped-v6
736 		 * are disallowed here when there is no sctp_sock.
737 		 */
738 		if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
739 			return 0;
740 		sctp_v6_map_v4(addr);
741 		return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb);
742 	}
743 
744 	/* Is this a non-unicast address */
745 	if (!(ret & IPV6_ADDR_UNICAST))
746 		return 0;
747 
748 	return 1;
749 }
750 
751 /* What is the scope of 'addr'?  */
sctp_v6_scope(union sctp_addr * addr)752 static enum sctp_scope sctp_v6_scope(union sctp_addr *addr)
753 {
754 	enum sctp_scope retval;
755 	int v6scope;
756 
757 	/* The IPv6 scope is really a set of bit fields.
758 	 * See IFA_* in <net/if_inet6.h>.  Map to a generic SCTP scope.
759 	 */
760 
761 	v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
762 	switch (v6scope) {
763 	case IFA_HOST:
764 		retval = SCTP_SCOPE_LOOPBACK;
765 		break;
766 	case IFA_LINK:
767 		retval = SCTP_SCOPE_LINK;
768 		break;
769 	case IFA_SITE:
770 		retval = SCTP_SCOPE_PRIVATE;
771 		break;
772 	default:
773 		retval = SCTP_SCOPE_GLOBAL;
774 		break;
775 	}
776 
777 	return retval;
778 }
779 
780 /* Create and initialize a new sk for the socket to be returned by accept(). */
sctp_v6_create_accept_sk(struct sock * sk,struct sctp_association * asoc,bool kern)781 static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
782 					     struct sctp_association *asoc,
783 					     bool kern)
784 {
785 	struct sock *newsk;
786 	struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
787 	struct sctp6_sock *newsctp6sk;
788 
789 	newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot, kern);
790 	if (!newsk)
791 		goto out;
792 
793 	sock_init_data(NULL, newsk);
794 
795 	sctp_copy_sock(newsk, sk, asoc);
796 	sock_reset_flag(sk, SOCK_ZAPPED);
797 
798 	newsctp6sk = (struct sctp6_sock *)newsk;
799 	inet_sk(newsk)->pinet6 = &newsctp6sk->inet6;
800 
801 	sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped;
802 
803 	newnp = inet6_sk(newsk);
804 
805 	memcpy(newnp, np, sizeof(struct ipv6_pinfo));
806 	newnp->ipv6_mc_list = NULL;
807 	newnp->ipv6_ac_list = NULL;
808 	newnp->ipv6_fl_list = NULL;
809 
810 	sctp_v6_copy_ip_options(sk, newsk);
811 
812 	/* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
813 	 * and getpeername().
814 	 */
815 	sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
816 
817 	newsk->sk_v6_rcv_saddr = sk->sk_v6_rcv_saddr;
818 
819 	if (newsk->sk_prot->init(newsk)) {
820 		sk_common_release(newsk);
821 		newsk = NULL;
822 	}
823 
824 out:
825 	return newsk;
826 }
827 
828 /* Format a sockaddr for return to user space. This makes sure the return is
829  * AF_INET or AF_INET6 depending on the SCTP_I_WANT_MAPPED_V4_ADDR option.
830  */
sctp_v6_addr_to_user(struct sctp_sock * sp,union sctp_addr * addr)831 static int sctp_v6_addr_to_user(struct sctp_sock *sp, union sctp_addr *addr)
832 {
833 	if (sp->v4mapped) {
834 		if (addr->sa.sa_family == AF_INET)
835 			sctp_v4_map_v6(addr);
836 	} else {
837 		if (addr->sa.sa_family == AF_INET6 &&
838 		    ipv6_addr_v4mapped(&addr->v6.sin6_addr))
839 			sctp_v6_map_v4(addr);
840 	}
841 
842 	if (addr->sa.sa_family == AF_INET) {
843 		memset(addr->v4.sin_zero, 0, sizeof(addr->v4.sin_zero));
844 		return sizeof(struct sockaddr_in);
845 	}
846 	return sizeof(struct sockaddr_in6);
847 }
848 
849 /* Where did this skb come from?  */
sctp_v6_skb_iif(const struct sk_buff * skb)850 static int sctp_v6_skb_iif(const struct sk_buff *skb)
851 {
852 	return inet6_iif(skb);
853 }
854 
sctp_v6_skb_sdif(const struct sk_buff * skb)855 static int sctp_v6_skb_sdif(const struct sk_buff *skb)
856 {
857 	return inet6_sdif(skb);
858 }
859 
860 /* Was this packet marked by Explicit Congestion Notification? */
sctp_v6_is_ce(const struct sk_buff * skb)861 static int sctp_v6_is_ce(const struct sk_buff *skb)
862 {
863 	return *((__u32 *)(ipv6_hdr(skb))) & (__force __u32)htonl(1 << 20);
864 }
865 
866 /* Dump the v6 addr to the seq file. */
sctp_v6_seq_dump_addr(struct seq_file * seq,union sctp_addr * addr)867 static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
868 {
869 	seq_printf(seq, "%pI6 ", &addr->v6.sin6_addr);
870 }
871 
sctp_v6_ecn_capable(struct sock * sk)872 static void sctp_v6_ecn_capable(struct sock *sk)
873 {
874 	inet6_sk(sk)->tclass |= INET_ECN_ECT_0;
875 }
876 
877 /* Initialize a PF_INET msgname from a ulpevent. */
sctp_inet6_event_msgname(struct sctp_ulpevent * event,char * msgname,int * addrlen)878 static void sctp_inet6_event_msgname(struct sctp_ulpevent *event,
879 				     char *msgname, int *addrlen)
880 {
881 	union sctp_addr *addr;
882 	struct sctp_association *asoc;
883 	union sctp_addr *paddr;
884 
885 	if (!msgname)
886 		return;
887 
888 	addr = (union sctp_addr *)msgname;
889 	asoc = event->asoc;
890 	paddr = &asoc->peer.primary_addr;
891 
892 	if (paddr->sa.sa_family == AF_INET) {
893 		addr->v4.sin_family = AF_INET;
894 		addr->v4.sin_port = htons(asoc->peer.port);
895 		addr->v4.sin_addr = paddr->v4.sin_addr;
896 	} else {
897 		addr->v6.sin6_family = AF_INET6;
898 		addr->v6.sin6_flowinfo = 0;
899 		if (ipv6_addr_type(&paddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
900 			addr->v6.sin6_scope_id = paddr->v6.sin6_scope_id;
901 		else
902 			addr->v6.sin6_scope_id = 0;
903 		addr->v6.sin6_port = htons(asoc->peer.port);
904 		addr->v6.sin6_addr = paddr->v6.sin6_addr;
905 	}
906 
907 	*addrlen = sctp_v6_addr_to_user(sctp_sk(asoc->base.sk), addr);
908 }
909 
910 /* Initialize a msg_name from an inbound skb. */
sctp_inet6_skb_msgname(struct sk_buff * skb,char * msgname,int * addr_len)911 static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname,
912 				   int *addr_len)
913 {
914 	union sctp_addr *addr;
915 	struct sctphdr *sh;
916 
917 	if (!msgname)
918 		return;
919 
920 	addr = (union sctp_addr *)msgname;
921 	sh = sctp_hdr(skb);
922 
923 	if (ip_hdr(skb)->version == 4) {
924 		addr->v4.sin_family = AF_INET;
925 		addr->v4.sin_port = sh->source;
926 		addr->v4.sin_addr.s_addr = ip_hdr(skb)->saddr;
927 	} else {
928 		addr->v6.sin6_family = AF_INET6;
929 		addr->v6.sin6_flowinfo = 0;
930 		addr->v6.sin6_port = sh->source;
931 		addr->v6.sin6_addr = ipv6_hdr(skb)->saddr;
932 		if (ipv6_addr_type(&addr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
933 			addr->v6.sin6_scope_id = sctp_v6_skb_iif(skb);
934 		else
935 			addr->v6.sin6_scope_id = 0;
936 	}
937 
938 	*addr_len = sctp_v6_addr_to_user(sctp_sk(skb->sk), addr);
939 }
940 
941 /* Do we support this AF? */
sctp_inet6_af_supported(sa_family_t family,struct sctp_sock * sp)942 static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp)
943 {
944 	switch (family) {
945 	case AF_INET6:
946 		return 1;
947 	/* v4-mapped-v6 addresses */
948 	case AF_INET:
949 		if (!ipv6_only_sock(sctp_opt2sk(sp)))
950 			return 1;
951 		fallthrough;
952 	default:
953 		return 0;
954 	}
955 }
956 
957 /* Address matching with wildcards allowed.  This extra level
958  * of indirection lets us choose whether a PF_INET6 should
959  * disallow any v4 addresses if we so choose.
960  */
sctp_inet6_cmp_addr(const union sctp_addr * addr1,const union sctp_addr * addr2,struct sctp_sock * opt)961 static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
962 			       const union sctp_addr *addr2,
963 			       struct sctp_sock *opt)
964 {
965 	struct sock *sk = sctp_opt2sk(opt);
966 	struct sctp_af *af1, *af2;
967 
968 	af1 = sctp_get_af_specific(addr1->sa.sa_family);
969 	af2 = sctp_get_af_specific(addr2->sa.sa_family);
970 
971 	if (!af1 || !af2)
972 		return 0;
973 
974 	/* If the socket is IPv6 only, v4 addrs will not match */
975 	if (ipv6_only_sock(sk) && af1 != af2)
976 		return 0;
977 
978 	/* Today, wildcard AF_INET/AF_INET6. */
979 	if (sctp_is_any(sk, addr1) || sctp_is_any(sk, addr2))
980 		return 1;
981 
982 	if (addr1->sa.sa_family == AF_INET && addr2->sa.sa_family == AF_INET)
983 		return addr1->v4.sin_addr.s_addr == addr2->v4.sin_addr.s_addr;
984 
985 	return __sctp_v6_cmp_addr(addr1, addr2);
986 }
987 
988 /* Verify that the provided sockaddr looks bindable.   Common verification,
989  * has already been taken care of.
990  */
sctp_inet6_bind_verify(struct sctp_sock * opt,union sctp_addr * addr)991 static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
992 {
993 	struct sctp_af *af;
994 
995 	/* ASSERT: address family has already been verified. */
996 	if (addr->sa.sa_family != AF_INET6)
997 		af = sctp_get_af_specific(addr->sa.sa_family);
998 	else {
999 		int type = ipv6_addr_type(&addr->v6.sin6_addr);
1000 		struct net_device *dev;
1001 
1002 		if (type & IPV6_ADDR_LINKLOCAL) {
1003 			struct net *net;
1004 			if (!addr->v6.sin6_scope_id)
1005 				return 0;
1006 			net = sock_net(&opt->inet.sk);
1007 			rcu_read_lock();
1008 			dev = dev_get_by_index_rcu(net, addr->v6.sin6_scope_id);
1009 			if (!dev || !(ipv6_can_nonlocal_bind(net, &opt->inet) ||
1010 				      ipv6_chk_addr(net, &addr->v6.sin6_addr,
1011 						    dev, 0))) {
1012 				rcu_read_unlock();
1013 				return 0;
1014 			}
1015 			rcu_read_unlock();
1016 		}
1017 
1018 		af = opt->pf->af;
1019 	}
1020 	return af->available(addr, opt);
1021 }
1022 
1023 /* Verify that the provided sockaddr looks sendable.   Common verification,
1024  * has already been taken care of.
1025  */
sctp_inet6_send_verify(struct sctp_sock * opt,union sctp_addr * addr)1026 static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
1027 {
1028 	struct sctp_af *af = NULL;
1029 
1030 	/* ASSERT: address family has already been verified. */
1031 	if (addr->sa.sa_family != AF_INET6)
1032 		af = sctp_get_af_specific(addr->sa.sa_family);
1033 	else {
1034 		int type = ipv6_addr_type(&addr->v6.sin6_addr);
1035 		struct net_device *dev;
1036 
1037 		if (type & IPV6_ADDR_LINKLOCAL) {
1038 			if (!addr->v6.sin6_scope_id)
1039 				return 0;
1040 			rcu_read_lock();
1041 			dev = dev_get_by_index_rcu(sock_net(&opt->inet.sk),
1042 						   addr->v6.sin6_scope_id);
1043 			rcu_read_unlock();
1044 			if (!dev)
1045 				return 0;
1046 		}
1047 		af = opt->pf->af;
1048 	}
1049 
1050 	return af != NULL;
1051 }
1052 
1053 /* Fill in Supported Address Type information for INIT and INIT-ACK
1054  * chunks.   Note: In the future, we may want to look at sock options
1055  * to determine whether a PF_INET6 socket really wants to have IPV4
1056  * addresses.
1057  * Returns number of addresses supported.
1058  */
sctp_inet6_supported_addrs(const struct sctp_sock * opt,__be16 * types)1059 static int sctp_inet6_supported_addrs(const struct sctp_sock *opt,
1060 				      __be16 *types)
1061 {
1062 	types[0] = SCTP_PARAM_IPV6_ADDRESS;
1063 	if (!opt || !ipv6_only_sock(sctp_opt2sk(opt))) {
1064 		types[1] = SCTP_PARAM_IPV4_ADDRESS;
1065 		return 2;
1066 	}
1067 	return 1;
1068 }
1069 
1070 /* Handle SCTP_I_WANT_MAPPED_V4_ADDR for getpeername() and getsockname() */
sctp_getname(struct socket * sock,struct sockaddr * uaddr,int peer)1071 static int sctp_getname(struct socket *sock, struct sockaddr *uaddr,
1072 			int peer)
1073 {
1074 	int rc;
1075 
1076 	rc = inet6_getname(sock, uaddr, peer);
1077 
1078 	if (rc < 0)
1079 		return rc;
1080 
1081 	rc = sctp_v6_addr_to_user(sctp_sk(sock->sk),
1082 					  (union sctp_addr *)uaddr);
1083 
1084 	return rc;
1085 }
1086 
1087 static const struct proto_ops inet6_seqpacket_ops = {
1088 	.family		   = PF_INET6,
1089 	.owner		   = THIS_MODULE,
1090 	.release	   = inet6_release,
1091 	.bind		   = inet6_bind,
1092 	.connect	   = sctp_inet_connect,
1093 	.socketpair	   = sock_no_socketpair,
1094 	.accept		   = inet_accept,
1095 	.getname	   = sctp_getname,
1096 	.poll		   = sctp_poll,
1097 	.ioctl		   = inet6_ioctl,
1098 	.gettstamp	   = sock_gettstamp,
1099 	.listen		   = sctp_inet_listen,
1100 	.shutdown	   = inet_shutdown,
1101 	.setsockopt	   = sock_common_setsockopt,
1102 	.getsockopt	   = sock_common_getsockopt,
1103 	.sendmsg	   = inet_sendmsg,
1104 	.recvmsg	   = inet_recvmsg,
1105 	.mmap		   = sock_no_mmap,
1106 #ifdef CONFIG_COMPAT
1107 	.compat_ioctl	   = inet6_compat_ioctl,
1108 #endif
1109 };
1110 
1111 static struct inet_protosw sctpv6_seqpacket_protosw = {
1112 	.type          = SOCK_SEQPACKET,
1113 	.protocol      = IPPROTO_SCTP,
1114 	.prot 	       = &sctpv6_prot,
1115 	.ops           = &inet6_seqpacket_ops,
1116 	.flags         = SCTP_PROTOSW_FLAG
1117 };
1118 static struct inet_protosw sctpv6_stream_protosw = {
1119 	.type          = SOCK_STREAM,
1120 	.protocol      = IPPROTO_SCTP,
1121 	.prot 	       = &sctpv6_prot,
1122 	.ops           = &inet6_seqpacket_ops,
1123 	.flags         = SCTP_PROTOSW_FLAG,
1124 };
1125 
sctp6_rcv(struct sk_buff * skb)1126 static int sctp6_rcv(struct sk_buff *skb)
1127 {
1128 	SCTP_INPUT_CB(skb)->encap_port = 0;
1129 	return sctp_rcv(skb) ? -1 : 0;
1130 }
1131 
1132 static const struct inet6_protocol sctpv6_protocol = {
1133 	.handler      = sctp6_rcv,
1134 	.err_handler  = sctp_v6_err,
1135 	.flags        = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
1136 };
1137 
1138 static struct sctp_af sctp_af_inet6 = {
1139 	.sa_family	   = AF_INET6,
1140 	.sctp_xmit	   = sctp_v6_xmit,
1141 	.setsockopt	   = ipv6_setsockopt,
1142 	.getsockopt	   = ipv6_getsockopt,
1143 	.get_dst	   = sctp_v6_get_dst,
1144 	.get_saddr	   = sctp_v6_get_saddr,
1145 	.copy_addrlist	   = sctp_v6_copy_addrlist,
1146 	.from_skb	   = sctp_v6_from_skb,
1147 	.from_sk	   = sctp_v6_from_sk,
1148 	.from_addr_param   = sctp_v6_from_addr_param,
1149 	.to_addr_param	   = sctp_v6_to_addr_param,
1150 	.cmp_addr	   = sctp_v6_cmp_addr,
1151 	.scope		   = sctp_v6_scope,
1152 	.addr_valid	   = sctp_v6_addr_valid,
1153 	.inaddr_any	   = sctp_v6_inaddr_any,
1154 	.is_any		   = sctp_v6_is_any,
1155 	.available	   = sctp_v6_available,
1156 	.skb_iif	   = sctp_v6_skb_iif,
1157 	.skb_sdif	   = sctp_v6_skb_sdif,
1158 	.is_ce		   = sctp_v6_is_ce,
1159 	.seq_dump_addr	   = sctp_v6_seq_dump_addr,
1160 	.ecn_capable	   = sctp_v6_ecn_capable,
1161 	.net_header_len	   = sizeof(struct ipv6hdr),
1162 	.sockaddr_len	   = sizeof(struct sockaddr_in6),
1163 	.ip_options_len	   = sctp_v6_ip_options_len,
1164 };
1165 
1166 static struct sctp_pf sctp_pf_inet6 = {
1167 	.event_msgname = sctp_inet6_event_msgname,
1168 	.skb_msgname   = sctp_inet6_skb_msgname,
1169 	.af_supported  = sctp_inet6_af_supported,
1170 	.cmp_addr      = sctp_inet6_cmp_addr,
1171 	.bind_verify   = sctp_inet6_bind_verify,
1172 	.send_verify   = sctp_inet6_send_verify,
1173 	.supported_addrs = sctp_inet6_supported_addrs,
1174 	.create_accept_sk = sctp_v6_create_accept_sk,
1175 	.addr_to_user  = sctp_v6_addr_to_user,
1176 	.to_sk_saddr   = sctp_v6_to_sk_saddr,
1177 	.to_sk_daddr   = sctp_v6_to_sk_daddr,
1178 	.copy_ip_options = sctp_v6_copy_ip_options,
1179 	.af            = &sctp_af_inet6,
1180 };
1181 
1182 /* Initialize IPv6 support and register with socket layer.  */
sctp_v6_pf_init(void)1183 void sctp_v6_pf_init(void)
1184 {
1185 	/* Register the SCTP specific PF_INET6 functions. */
1186 	sctp_register_pf(&sctp_pf_inet6, PF_INET6);
1187 
1188 	/* Register the SCTP specific AF_INET6 functions. */
1189 	sctp_register_af(&sctp_af_inet6);
1190 }
1191 
sctp_v6_pf_exit(void)1192 void sctp_v6_pf_exit(void)
1193 {
1194 	list_del(&sctp_af_inet6.list);
1195 }
1196 
1197 /* Initialize IPv6 support and register with socket layer.  */
sctp_v6_protosw_init(void)1198 int sctp_v6_protosw_init(void)
1199 {
1200 	int rc;
1201 
1202 	rc = proto_register(&sctpv6_prot, 1);
1203 	if (rc)
1204 		return rc;
1205 
1206 	/* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
1207 	inet6_register_protosw(&sctpv6_seqpacket_protosw);
1208 	inet6_register_protosw(&sctpv6_stream_protosw);
1209 
1210 	return 0;
1211 }
1212 
sctp_v6_protosw_exit(void)1213 void sctp_v6_protosw_exit(void)
1214 {
1215 	inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
1216 	inet6_unregister_protosw(&sctpv6_stream_protosw);
1217 	proto_unregister(&sctpv6_prot);
1218 }
1219 
1220 
1221 /* Register with inet6 layer. */
sctp_v6_add_protocol(void)1222 int sctp_v6_add_protocol(void)
1223 {
1224 	/* Register notifier for inet6 address additions/deletions. */
1225 	register_inet6addr_notifier(&sctp_inet6addr_notifier);
1226 
1227 	if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
1228 		return -EAGAIN;
1229 
1230 	return 0;
1231 }
1232 
1233 /* Unregister with inet6 layer. */
sctp_v6_del_protocol(void)1234 void sctp_v6_del_protocol(void)
1235 {
1236 	inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
1237 	unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
1238 }
1239