xref: /openbmc/linux/net/sctp/protocol.c (revision 3f7e7532)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* SCTP kernel implementation
3  * (C) Copyright IBM Corp. 2001, 2004
4  * Copyright (c) 1999-2000 Cisco, Inc.
5  * Copyright (c) 1999-2001 Motorola, Inc.
6  * Copyright (c) 2001 Intel Corp.
7  * Copyright (c) 2001 Nokia, Inc.
8  * Copyright (c) 2001 La Monte H.P. Yarroll
9  *
10  * This file is part of the SCTP kernel implementation
11  *
12  * Initialization/cleanup for SCTP protocol support.
13  *
14  * Please send any bug reports or fixes you make to the
15  * email address(es):
16  *    lksctp developers <linux-sctp@vger.kernel.org>
17  *
18  * Written or modified by:
19  *    La Monte H.P. Yarroll <piggy@acm.org>
20  *    Karl Knutson <karl@athena.chicago.il.us>
21  *    Jon Grimm <jgrimm@us.ibm.com>
22  *    Sridhar Samudrala <sri@us.ibm.com>
23  *    Daisy Chang <daisyc@us.ibm.com>
24  *    Ardelle Fan <ardelle.fan@intel.com>
25  */
26 
27 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
28 
29 #include <linux/module.h>
30 #include <linux/init.h>
31 #include <linux/netdevice.h>
32 #include <linux/inetdevice.h>
33 #include <linux/seq_file.h>
34 #include <linux/memblock.h>
35 #include <linux/highmem.h>
36 #include <linux/slab.h>
37 #include <net/net_namespace.h>
38 #include <net/protocol.h>
39 #include <net/ip.h>
40 #include <net/ipv6.h>
41 #include <net/route.h>
42 #include <net/sctp/sctp.h>
43 #include <net/addrconf.h>
44 #include <net/inet_common.h>
45 #include <net/inet_ecn.h>
46 #include <net/udp_tunnel.h>
47 
48 #define MAX_SCTP_PORT_HASH_ENTRIES (64 * 1024)
49 
50 /* Global data structures. */
51 struct sctp_globals sctp_globals __read_mostly;
52 
53 struct idr sctp_assocs_id;
54 DEFINE_SPINLOCK(sctp_assocs_id_lock);
55 
56 static struct sctp_pf *sctp_pf_inet6_specific;
57 static struct sctp_pf *sctp_pf_inet_specific;
58 static struct sctp_af *sctp_af_v4_specific;
59 static struct sctp_af *sctp_af_v6_specific;
60 
61 struct kmem_cache *sctp_chunk_cachep __read_mostly;
62 struct kmem_cache *sctp_bucket_cachep __read_mostly;
63 
64 long sysctl_sctp_mem[3];
65 int sysctl_sctp_rmem[3];
66 int sysctl_sctp_wmem[3];
67 
68 /* Private helper to extract ipv4 address and stash them in
69  * the protocol structure.
70  */
sctp_v4_copy_addrlist(struct list_head * addrlist,struct net_device * dev)71 static void sctp_v4_copy_addrlist(struct list_head *addrlist,
72 				  struct net_device *dev)
73 {
74 	struct in_device *in_dev;
75 	struct in_ifaddr *ifa;
76 	struct sctp_sockaddr_entry *addr;
77 
78 	rcu_read_lock();
79 	if ((in_dev = __in_dev_get_rcu(dev)) == NULL) {
80 		rcu_read_unlock();
81 		return;
82 	}
83 
84 	in_dev_for_each_ifa_rcu(ifa, in_dev) {
85 		/* Add the address to the local list.  */
86 		addr = kzalloc(sizeof(*addr), GFP_ATOMIC);
87 		if (addr) {
88 			addr->a.v4.sin_family = AF_INET;
89 			addr->a.v4.sin_addr.s_addr = ifa->ifa_local;
90 			addr->valid = 1;
91 			INIT_LIST_HEAD(&addr->list);
92 			list_add_tail(&addr->list, addrlist);
93 		}
94 	}
95 
96 	rcu_read_unlock();
97 }
98 
99 /* Extract our IP addresses from the system and stash them in the
100  * protocol structure.
101  */
sctp_get_local_addr_list(struct net * net)102 static void sctp_get_local_addr_list(struct net *net)
103 {
104 	struct net_device *dev;
105 	struct list_head *pos;
106 	struct sctp_af *af;
107 
108 	rcu_read_lock();
109 	for_each_netdev_rcu(net, dev) {
110 		list_for_each(pos, &sctp_address_families) {
111 			af = list_entry(pos, struct sctp_af, list);
112 			af->copy_addrlist(&net->sctp.local_addr_list, dev);
113 		}
114 	}
115 	rcu_read_unlock();
116 }
117 
118 /* Free the existing local addresses.  */
sctp_free_local_addr_list(struct net * net)119 static void sctp_free_local_addr_list(struct net *net)
120 {
121 	struct sctp_sockaddr_entry *addr;
122 	struct list_head *pos, *temp;
123 
124 	list_for_each_safe(pos, temp, &net->sctp.local_addr_list) {
125 		addr = list_entry(pos, struct sctp_sockaddr_entry, list);
126 		list_del(pos);
127 		kfree(addr);
128 	}
129 }
130 
131 /* Copy the local addresses which are valid for 'scope' into 'bp'.  */
sctp_copy_local_addr_list(struct net * net,struct sctp_bind_addr * bp,enum sctp_scope scope,gfp_t gfp,int copy_flags)132 int sctp_copy_local_addr_list(struct net *net, struct sctp_bind_addr *bp,
133 			      enum sctp_scope scope, gfp_t gfp, int copy_flags)
134 {
135 	struct sctp_sockaddr_entry *addr;
136 	union sctp_addr laddr;
137 	int error = 0;
138 
139 	rcu_read_lock();
140 	list_for_each_entry_rcu(addr, &net->sctp.local_addr_list, list) {
141 		if (!addr->valid)
142 			continue;
143 		if (!sctp_in_scope(net, &addr->a, scope))
144 			continue;
145 
146 		/* Now that the address is in scope, check to see if
147 		 * the address type is really supported by the local
148 		 * sock as well as the remote peer.
149 		 */
150 		if (addr->a.sa.sa_family == AF_INET &&
151 		    (!(copy_flags & SCTP_ADDR4_ALLOWED) ||
152 		     !(copy_flags & SCTP_ADDR4_PEERSUPP)))
153 			continue;
154 		if (addr->a.sa.sa_family == AF_INET6 &&
155 		    (!(copy_flags & SCTP_ADDR6_ALLOWED) ||
156 		     !(copy_flags & SCTP_ADDR6_PEERSUPP)))
157 			continue;
158 
159 		laddr = addr->a;
160 		/* also works for setting ipv6 address port */
161 		laddr.v4.sin_port = htons(bp->port);
162 		if (sctp_bind_addr_state(bp, &laddr) != -1)
163 			continue;
164 
165 		error = sctp_add_bind_addr(bp, &addr->a, sizeof(addr->a),
166 					   SCTP_ADDR_SRC, GFP_ATOMIC);
167 		if (error)
168 			break;
169 	}
170 
171 	rcu_read_unlock();
172 	return error;
173 }
174 
175 /* Copy over any ip options */
sctp_v4_copy_ip_options(struct sock * sk,struct sock * newsk)176 static void sctp_v4_copy_ip_options(struct sock *sk, struct sock *newsk)
177 {
178 	struct inet_sock *newinet, *inet = inet_sk(sk);
179 	struct ip_options_rcu *inet_opt, *newopt = NULL;
180 
181 	newinet = inet_sk(newsk);
182 
183 	rcu_read_lock();
184 	inet_opt = rcu_dereference(inet->inet_opt);
185 	if (inet_opt) {
186 		newopt = sock_kmalloc(newsk, sizeof(*inet_opt) +
187 				      inet_opt->opt.optlen, GFP_ATOMIC);
188 		if (newopt)
189 			memcpy(newopt, inet_opt, sizeof(*inet_opt) +
190 			       inet_opt->opt.optlen);
191 		else
192 			pr_err("%s: Failed to copy ip options\n", __func__);
193 	}
194 	RCU_INIT_POINTER(newinet->inet_opt, newopt);
195 	rcu_read_unlock();
196 }
197 
198 /* Account for the IP options */
sctp_v4_ip_options_len(struct sock * sk)199 static int sctp_v4_ip_options_len(struct sock *sk)
200 {
201 	struct inet_sock *inet = inet_sk(sk);
202 	struct ip_options_rcu *inet_opt;
203 	int len = 0;
204 
205 	rcu_read_lock();
206 	inet_opt = rcu_dereference(inet->inet_opt);
207 	if (inet_opt)
208 		len = inet_opt->opt.optlen;
209 
210 	rcu_read_unlock();
211 	return len;
212 }
213 
214 /* Initialize a sctp_addr from in incoming skb.  */
sctp_v4_from_skb(union sctp_addr * addr,struct sk_buff * skb,int is_saddr)215 static void sctp_v4_from_skb(union sctp_addr *addr, struct sk_buff *skb,
216 			     int is_saddr)
217 {
218 	/* Always called on head skb, so this is safe */
219 	struct sctphdr *sh = sctp_hdr(skb);
220 	struct sockaddr_in *sa = &addr->v4;
221 
222 	addr->v4.sin_family = AF_INET;
223 
224 	if (is_saddr) {
225 		sa->sin_port = sh->source;
226 		sa->sin_addr.s_addr = ip_hdr(skb)->saddr;
227 	} else {
228 		sa->sin_port = sh->dest;
229 		sa->sin_addr.s_addr = ip_hdr(skb)->daddr;
230 	}
231 	memset(sa->sin_zero, 0, sizeof(sa->sin_zero));
232 }
233 
234 /* Initialize an sctp_addr from a socket. */
sctp_v4_from_sk(union sctp_addr * addr,struct sock * sk)235 static void sctp_v4_from_sk(union sctp_addr *addr, struct sock *sk)
236 {
237 	addr->v4.sin_family = AF_INET;
238 	addr->v4.sin_port = 0;
239 	addr->v4.sin_addr.s_addr = inet_sk(sk)->inet_rcv_saddr;
240 	memset(addr->v4.sin_zero, 0, sizeof(addr->v4.sin_zero));
241 }
242 
243 /* Initialize sk->sk_rcv_saddr from sctp_addr. */
sctp_v4_to_sk_saddr(union sctp_addr * addr,struct sock * sk)244 static void sctp_v4_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
245 {
246 	inet_sk(sk)->inet_rcv_saddr = addr->v4.sin_addr.s_addr;
247 }
248 
249 /* Initialize sk->sk_daddr from sctp_addr. */
sctp_v4_to_sk_daddr(union sctp_addr * addr,struct sock * sk)250 static void sctp_v4_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
251 {
252 	inet_sk(sk)->inet_daddr = addr->v4.sin_addr.s_addr;
253 }
254 
255 /* Initialize a sctp_addr from an address parameter. */
sctp_v4_from_addr_param(union sctp_addr * addr,union sctp_addr_param * param,__be16 port,int iif)256 static bool sctp_v4_from_addr_param(union sctp_addr *addr,
257 				    union sctp_addr_param *param,
258 				    __be16 port, int iif)
259 {
260 	if (ntohs(param->v4.param_hdr.length) < sizeof(struct sctp_ipv4addr_param))
261 		return false;
262 
263 	addr->v4.sin_family = AF_INET;
264 	addr->v4.sin_port = port;
265 	addr->v4.sin_addr.s_addr = param->v4.addr.s_addr;
266 	memset(addr->v4.sin_zero, 0, sizeof(addr->v4.sin_zero));
267 
268 	return true;
269 }
270 
271 /* Initialize an address parameter from a sctp_addr and return the length
272  * of the address parameter.
273  */
sctp_v4_to_addr_param(const union sctp_addr * addr,union sctp_addr_param * param)274 static int sctp_v4_to_addr_param(const union sctp_addr *addr,
275 				 union sctp_addr_param *param)
276 {
277 	int length = sizeof(struct sctp_ipv4addr_param);
278 
279 	param->v4.param_hdr.type = SCTP_PARAM_IPV4_ADDRESS;
280 	param->v4.param_hdr.length = htons(length);
281 	param->v4.addr.s_addr = addr->v4.sin_addr.s_addr;
282 
283 	return length;
284 }
285 
286 /* Initialize a sctp_addr from a dst_entry. */
sctp_v4_dst_saddr(union sctp_addr * saddr,struct flowi4 * fl4,__be16 port)287 static void sctp_v4_dst_saddr(union sctp_addr *saddr, struct flowi4 *fl4,
288 			      __be16 port)
289 {
290 	saddr->v4.sin_family = AF_INET;
291 	saddr->v4.sin_port = port;
292 	saddr->v4.sin_addr.s_addr = fl4->saddr;
293 	memset(saddr->v4.sin_zero, 0, sizeof(saddr->v4.sin_zero));
294 }
295 
296 /* Compare two addresses exactly. */
sctp_v4_cmp_addr(const union sctp_addr * addr1,const union sctp_addr * addr2)297 static int sctp_v4_cmp_addr(const union sctp_addr *addr1,
298 			    const union sctp_addr *addr2)
299 {
300 	if (addr1->sa.sa_family != addr2->sa.sa_family)
301 		return 0;
302 	if (addr1->v4.sin_port != addr2->v4.sin_port)
303 		return 0;
304 	if (addr1->v4.sin_addr.s_addr != addr2->v4.sin_addr.s_addr)
305 		return 0;
306 
307 	return 1;
308 }
309 
310 /* Initialize addr struct to INADDR_ANY. */
sctp_v4_inaddr_any(union sctp_addr * addr,__be16 port)311 static void sctp_v4_inaddr_any(union sctp_addr *addr, __be16 port)
312 {
313 	addr->v4.sin_family = AF_INET;
314 	addr->v4.sin_addr.s_addr = htonl(INADDR_ANY);
315 	addr->v4.sin_port = port;
316 	memset(addr->v4.sin_zero, 0, sizeof(addr->v4.sin_zero));
317 }
318 
319 /* Is this a wildcard address? */
sctp_v4_is_any(const union sctp_addr * addr)320 static int sctp_v4_is_any(const union sctp_addr *addr)
321 {
322 	return htonl(INADDR_ANY) == addr->v4.sin_addr.s_addr;
323 }
324 
325 /* This function checks if the address is a valid address to be used for
326  * SCTP binding.
327  *
328  * Output:
329  * Return 0 - If the address is a non-unicast or an illegal address.
330  * Return 1 - If the address is a unicast.
331  */
sctp_v4_addr_valid(union sctp_addr * addr,struct sctp_sock * sp,const struct sk_buff * skb)332 static int sctp_v4_addr_valid(union sctp_addr *addr,
333 			      struct sctp_sock *sp,
334 			      const struct sk_buff *skb)
335 {
336 	/* IPv4 addresses not allowed */
337 	if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
338 		return 0;
339 
340 	/* Is this a non-unicast address or a unusable SCTP address? */
341 	if (IS_IPV4_UNUSABLE_ADDRESS(addr->v4.sin_addr.s_addr))
342 		return 0;
343 
344 	/* Is this a broadcast address? */
345 	if (skb && skb_rtable(skb)->rt_flags & RTCF_BROADCAST)
346 		return 0;
347 
348 	return 1;
349 }
350 
351 /* Should this be available for binding?   */
sctp_v4_available(union sctp_addr * addr,struct sctp_sock * sp)352 static int sctp_v4_available(union sctp_addr *addr, struct sctp_sock *sp)
353 {
354 	struct sock *sk = &sp->inet.sk;
355 	struct net *net = sock_net(sk);
356 	int tb_id = RT_TABLE_LOCAL;
357 	int ret;
358 
359 	tb_id = l3mdev_fib_table_by_index(net, sk->sk_bound_dev_if) ?: tb_id;
360 	ret = inet_addr_type_table(net, addr->v4.sin_addr.s_addr, tb_id);
361 	if (addr->v4.sin_addr.s_addr != htonl(INADDR_ANY) &&
362 	   ret != RTN_LOCAL &&
363 	   !inet_test_bit(FREEBIND, sk) &&
364 	    !READ_ONCE(net->ipv4.sysctl_ip_nonlocal_bind))
365 		return 0;
366 
367 	if (ipv6_only_sock(sctp_opt2sk(sp)))
368 		return 0;
369 
370 	return 1;
371 }
372 
373 /* Checking the loopback, private and other address scopes as defined in
374  * RFC 1918.   The IPv4 scoping is based on the draft for SCTP IPv4
375  * scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>.
376  *
377  * Level 0 - unusable SCTP addresses
378  * Level 1 - loopback address
379  * Level 2 - link-local addresses
380  * Level 3 - private addresses.
381  * Level 4 - global addresses
382  * For INIT and INIT-ACK address list, let L be the level of
383  * requested destination address, sender and receiver
384  * SHOULD include all of its addresses with level greater
385  * than or equal to L.
386  *
387  * IPv4 scoping can be controlled through sysctl option
388  * net.sctp.addr_scope_policy
389  */
sctp_v4_scope(union sctp_addr * addr)390 static enum sctp_scope sctp_v4_scope(union sctp_addr *addr)
391 {
392 	enum sctp_scope retval;
393 
394 	/* Check for unusable SCTP addresses. */
395 	if (IS_IPV4_UNUSABLE_ADDRESS(addr->v4.sin_addr.s_addr)) {
396 		retval =  SCTP_SCOPE_UNUSABLE;
397 	} else if (ipv4_is_loopback(addr->v4.sin_addr.s_addr)) {
398 		retval = SCTP_SCOPE_LOOPBACK;
399 	} else if (ipv4_is_linklocal_169(addr->v4.sin_addr.s_addr)) {
400 		retval = SCTP_SCOPE_LINK;
401 	} else if (ipv4_is_private_10(addr->v4.sin_addr.s_addr) ||
402 		   ipv4_is_private_172(addr->v4.sin_addr.s_addr) ||
403 		   ipv4_is_private_192(addr->v4.sin_addr.s_addr) ||
404 		   ipv4_is_test_198(addr->v4.sin_addr.s_addr)) {
405 		retval = SCTP_SCOPE_PRIVATE;
406 	} else {
407 		retval = SCTP_SCOPE_GLOBAL;
408 	}
409 
410 	return retval;
411 }
412 
413 /* Returns a valid dst cache entry for the given source and destination ip
414  * addresses. If an association is passed, trys to get a dst entry with a
415  * source address that matches an address in the bind address list.
416  */
sctp_v4_get_dst(struct sctp_transport * t,union sctp_addr * saddr,struct flowi * fl,struct sock * sk)417 static void sctp_v4_get_dst(struct sctp_transport *t, union sctp_addr *saddr,
418 				struct flowi *fl, struct sock *sk)
419 {
420 	struct sctp_association *asoc = t->asoc;
421 	struct rtable *rt;
422 	struct flowi _fl;
423 	struct flowi4 *fl4 = &_fl.u.ip4;
424 	struct sctp_bind_addr *bp;
425 	struct sctp_sockaddr_entry *laddr;
426 	struct dst_entry *dst = NULL;
427 	union sctp_addr *daddr = &t->ipaddr;
428 	union sctp_addr dst_saddr;
429 	__u8 tos = inet_sk(sk)->tos;
430 
431 	if (t->dscp & SCTP_DSCP_SET_MASK)
432 		tos = t->dscp & SCTP_DSCP_VAL_MASK;
433 	memset(&_fl, 0x0, sizeof(_fl));
434 	fl4->daddr  = daddr->v4.sin_addr.s_addr;
435 	fl4->fl4_dport = daddr->v4.sin_port;
436 	fl4->flowi4_proto = IPPROTO_SCTP;
437 	if (asoc) {
438 		fl4->flowi4_tos = RT_TOS(tos);
439 		fl4->flowi4_scope = ip_sock_rt_scope(asoc->base.sk);
440 		fl4->flowi4_oif = asoc->base.sk->sk_bound_dev_if;
441 		fl4->fl4_sport = htons(asoc->base.bind_addr.port);
442 	}
443 	if (saddr) {
444 		fl4->saddr = saddr->v4.sin_addr.s_addr;
445 		if (!fl4->fl4_sport)
446 			fl4->fl4_sport = saddr->v4.sin_port;
447 	}
448 
449 	pr_debug("%s: dst:%pI4, src:%pI4 - ", __func__, &fl4->daddr,
450 		 &fl4->saddr);
451 
452 	rt = ip_route_output_key(sock_net(sk), fl4);
453 	if (!IS_ERR(rt)) {
454 		dst = &rt->dst;
455 		t->dst = dst;
456 		memcpy(fl, &_fl, sizeof(_fl));
457 	}
458 
459 	/* If there is no association or if a source address is passed, no
460 	 * more validation is required.
461 	 */
462 	if (!asoc || saddr)
463 		goto out;
464 
465 	bp = &asoc->base.bind_addr;
466 
467 	if (dst) {
468 		/* Walk through the bind address list and look for a bind
469 		 * address that matches the source address of the returned dst.
470 		 */
471 		sctp_v4_dst_saddr(&dst_saddr, fl4, htons(bp->port));
472 		rcu_read_lock();
473 		list_for_each_entry_rcu(laddr, &bp->address_list, list) {
474 			if (!laddr->valid || (laddr->state == SCTP_ADDR_DEL) ||
475 			    (laddr->state != SCTP_ADDR_SRC &&
476 			    !asoc->src_out_of_asoc_ok))
477 				continue;
478 			if (sctp_v4_cmp_addr(&dst_saddr, &laddr->a))
479 				goto out_unlock;
480 		}
481 		rcu_read_unlock();
482 
483 		/* None of the bound addresses match the source address of the
484 		 * dst. So release it.
485 		 */
486 		dst_release(dst);
487 		dst = NULL;
488 	}
489 
490 	/* Walk through the bind address list and try to get a dst that
491 	 * matches a bind address as the source address.
492 	 */
493 	rcu_read_lock();
494 	list_for_each_entry_rcu(laddr, &bp->address_list, list) {
495 		struct net_device *odev;
496 
497 		if (!laddr->valid)
498 			continue;
499 		if (laddr->state != SCTP_ADDR_SRC ||
500 		    AF_INET != laddr->a.sa.sa_family)
501 			continue;
502 
503 		fl4->fl4_sport = laddr->a.v4.sin_port;
504 		flowi4_update_output(fl4, asoc->base.sk->sk_bound_dev_if,
505 				     daddr->v4.sin_addr.s_addr,
506 				     laddr->a.v4.sin_addr.s_addr);
507 
508 		rt = ip_route_output_key(sock_net(sk), fl4);
509 		if (IS_ERR(rt))
510 			continue;
511 
512 		/* Ensure the src address belongs to the output
513 		 * interface.
514 		 */
515 		odev = __ip_dev_find(sock_net(sk), laddr->a.v4.sin_addr.s_addr,
516 				     false);
517 		if (!odev || odev->ifindex != fl4->flowi4_oif) {
518 			if (!dst) {
519 				dst = &rt->dst;
520 				t->dst = dst;
521 				memcpy(fl, &_fl, sizeof(_fl));
522 			} else {
523 				dst_release(&rt->dst);
524 			}
525 			continue;
526 		}
527 
528 		dst_release(dst);
529 		dst = &rt->dst;
530 		t->dst = dst;
531 		memcpy(fl, &_fl, sizeof(_fl));
532 		break;
533 	}
534 
535 out_unlock:
536 	rcu_read_unlock();
537 out:
538 	if (dst) {
539 		pr_debug("rt_dst:%pI4, rt_src:%pI4\n",
540 			 &fl->u.ip4.daddr, &fl->u.ip4.saddr);
541 	} else {
542 		t->dst = NULL;
543 		pr_debug("no route\n");
544 	}
545 }
546 
547 /* For v4, the source address is cached in the route entry(dst). So no need
548  * to cache it separately and hence this is an empty routine.
549  */
sctp_v4_get_saddr(struct sctp_sock * sk,struct sctp_transport * t,struct flowi * fl)550 static void sctp_v4_get_saddr(struct sctp_sock *sk,
551 			      struct sctp_transport *t,
552 			      struct flowi *fl)
553 {
554 	union sctp_addr *saddr = &t->saddr;
555 	struct rtable *rt = (struct rtable *)t->dst;
556 
557 	if (rt) {
558 		saddr->v4.sin_family = AF_INET;
559 		saddr->v4.sin_addr.s_addr = fl->u.ip4.saddr;
560 	}
561 }
562 
563 /* What interface did this skb arrive on? */
sctp_v4_skb_iif(const struct sk_buff * skb)564 static int sctp_v4_skb_iif(const struct sk_buff *skb)
565 {
566 	return inet_iif(skb);
567 }
568 
sctp_v4_skb_sdif(const struct sk_buff * skb)569 static int sctp_v4_skb_sdif(const struct sk_buff *skb)
570 {
571 	return inet_sdif(skb);
572 }
573 
574 /* Was this packet marked by Explicit Congestion Notification? */
sctp_v4_is_ce(const struct sk_buff * skb)575 static int sctp_v4_is_ce(const struct sk_buff *skb)
576 {
577 	return INET_ECN_is_ce(ip_hdr(skb)->tos);
578 }
579 
580 /* Create and initialize a new sk for the socket returned by accept(). */
sctp_v4_create_accept_sk(struct sock * sk,struct sctp_association * asoc,bool kern)581 static struct sock *sctp_v4_create_accept_sk(struct sock *sk,
582 					     struct sctp_association *asoc,
583 					     bool kern)
584 {
585 	struct sock *newsk = sk_alloc(sock_net(sk), PF_INET, GFP_KERNEL,
586 			sk->sk_prot, kern);
587 	struct inet_sock *newinet;
588 
589 	if (!newsk)
590 		goto out;
591 
592 	sock_init_data(NULL, newsk);
593 
594 	sctp_copy_sock(newsk, sk, asoc);
595 	sock_reset_flag(newsk, SOCK_ZAPPED);
596 
597 	sctp_v4_copy_ip_options(sk, newsk);
598 
599 	newinet = inet_sk(newsk);
600 
601 	newinet->inet_daddr = asoc->peer.primary_addr.v4.sin_addr.s_addr;
602 
603 	if (newsk->sk_prot->init(newsk)) {
604 		sk_common_release(newsk);
605 		newsk = NULL;
606 	}
607 
608 out:
609 	return newsk;
610 }
611 
sctp_v4_addr_to_user(struct sctp_sock * sp,union sctp_addr * addr)612 static int sctp_v4_addr_to_user(struct sctp_sock *sp, union sctp_addr *addr)
613 {
614 	/* No address mapping for V4 sockets */
615 	memset(addr->v4.sin_zero, 0, sizeof(addr->v4.sin_zero));
616 	return sizeof(struct sockaddr_in);
617 }
618 
619 /* Dump the v4 addr to the seq file. */
sctp_v4_seq_dump_addr(struct seq_file * seq,union sctp_addr * addr)620 static void sctp_v4_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
621 {
622 	seq_printf(seq, "%pI4 ", &addr->v4.sin_addr);
623 }
624 
sctp_v4_ecn_capable(struct sock * sk)625 static void sctp_v4_ecn_capable(struct sock *sk)
626 {
627 	INET_ECN_xmit(sk);
628 }
629 
sctp_addr_wq_timeout_handler(struct timer_list * t)630 static void sctp_addr_wq_timeout_handler(struct timer_list *t)
631 {
632 	struct net *net = from_timer(net, t, sctp.addr_wq_timer);
633 	struct sctp_sockaddr_entry *addrw, *temp;
634 	struct sctp_sock *sp;
635 
636 	spin_lock_bh(&net->sctp.addr_wq_lock);
637 
638 	list_for_each_entry_safe(addrw, temp, &net->sctp.addr_waitq, list) {
639 		pr_debug("%s: the first ent in wq:%p is addr:%pISc for cmd:%d at "
640 			 "entry:%p\n", __func__, &net->sctp.addr_waitq, &addrw->a.sa,
641 			 addrw->state, addrw);
642 
643 #if IS_ENABLED(CONFIG_IPV6)
644 		/* Now we send an ASCONF for each association */
645 		/* Note. we currently don't handle link local IPv6 addressees */
646 		if (addrw->a.sa.sa_family == AF_INET6) {
647 			struct in6_addr *in6;
648 
649 			if (ipv6_addr_type(&addrw->a.v6.sin6_addr) &
650 			    IPV6_ADDR_LINKLOCAL)
651 				goto free_next;
652 
653 			in6 = (struct in6_addr *)&addrw->a.v6.sin6_addr;
654 			if (ipv6_chk_addr(net, in6, NULL, 0) == 0 &&
655 			    addrw->state == SCTP_ADDR_NEW) {
656 				unsigned long timeo_val;
657 
658 				pr_debug("%s: this is on DAD, trying %d sec "
659 					 "later\n", __func__,
660 					 SCTP_ADDRESS_TICK_DELAY);
661 
662 				timeo_val = jiffies;
663 				timeo_val += msecs_to_jiffies(SCTP_ADDRESS_TICK_DELAY);
664 				mod_timer(&net->sctp.addr_wq_timer, timeo_val);
665 				break;
666 			}
667 		}
668 #endif
669 		list_for_each_entry(sp, &net->sctp.auto_asconf_splist, auto_asconf_list) {
670 			struct sock *sk;
671 
672 			sk = sctp_opt2sk(sp);
673 			/* ignore bound-specific endpoints */
674 			if (!sctp_is_ep_boundall(sk))
675 				continue;
676 			bh_lock_sock(sk);
677 			if (sctp_asconf_mgmt(sp, addrw) < 0)
678 				pr_debug("%s: sctp_asconf_mgmt failed\n", __func__);
679 			bh_unlock_sock(sk);
680 		}
681 #if IS_ENABLED(CONFIG_IPV6)
682 free_next:
683 #endif
684 		list_del(&addrw->list);
685 		kfree(addrw);
686 	}
687 	spin_unlock_bh(&net->sctp.addr_wq_lock);
688 }
689 
sctp_free_addr_wq(struct net * net)690 static void sctp_free_addr_wq(struct net *net)
691 {
692 	struct sctp_sockaddr_entry *addrw;
693 	struct sctp_sockaddr_entry *temp;
694 
695 	spin_lock_bh(&net->sctp.addr_wq_lock);
696 	del_timer(&net->sctp.addr_wq_timer);
697 	list_for_each_entry_safe(addrw, temp, &net->sctp.addr_waitq, list) {
698 		list_del(&addrw->list);
699 		kfree(addrw);
700 	}
701 	spin_unlock_bh(&net->sctp.addr_wq_lock);
702 }
703 
704 /* lookup the entry for the same address in the addr_waitq
705  * sctp_addr_wq MUST be locked
706  */
sctp_addr_wq_lookup(struct net * net,struct sctp_sockaddr_entry * addr)707 static struct sctp_sockaddr_entry *sctp_addr_wq_lookup(struct net *net,
708 					struct sctp_sockaddr_entry *addr)
709 {
710 	struct sctp_sockaddr_entry *addrw;
711 
712 	list_for_each_entry(addrw, &net->sctp.addr_waitq, list) {
713 		if (addrw->a.sa.sa_family != addr->a.sa.sa_family)
714 			continue;
715 		if (addrw->a.sa.sa_family == AF_INET) {
716 			if (addrw->a.v4.sin_addr.s_addr ==
717 			    addr->a.v4.sin_addr.s_addr)
718 				return addrw;
719 		} else if (addrw->a.sa.sa_family == AF_INET6) {
720 			if (ipv6_addr_equal(&addrw->a.v6.sin6_addr,
721 			    &addr->a.v6.sin6_addr))
722 				return addrw;
723 		}
724 	}
725 	return NULL;
726 }
727 
sctp_addr_wq_mgmt(struct net * net,struct sctp_sockaddr_entry * addr,int cmd)728 void sctp_addr_wq_mgmt(struct net *net, struct sctp_sockaddr_entry *addr, int cmd)
729 {
730 	struct sctp_sockaddr_entry *addrw;
731 	unsigned long timeo_val;
732 
733 	/* first, we check if an opposite message already exist in the queue.
734 	 * If we found such message, it is removed.
735 	 * This operation is a bit stupid, but the DHCP client attaches the
736 	 * new address after a couple of addition and deletion of that address
737 	 */
738 
739 	spin_lock_bh(&net->sctp.addr_wq_lock);
740 	/* Offsets existing events in addr_wq */
741 	addrw = sctp_addr_wq_lookup(net, addr);
742 	if (addrw) {
743 		if (addrw->state != cmd) {
744 			pr_debug("%s: offsets existing entry for %d, addr:%pISc "
745 				 "in wq:%p\n", __func__, addrw->state, &addrw->a.sa,
746 				 &net->sctp.addr_waitq);
747 
748 			list_del(&addrw->list);
749 			kfree(addrw);
750 		}
751 		spin_unlock_bh(&net->sctp.addr_wq_lock);
752 		return;
753 	}
754 
755 	/* OK, we have to add the new address to the wait queue */
756 	addrw = kmemdup(addr, sizeof(struct sctp_sockaddr_entry), GFP_ATOMIC);
757 	if (addrw == NULL) {
758 		spin_unlock_bh(&net->sctp.addr_wq_lock);
759 		return;
760 	}
761 	addrw->state = cmd;
762 	list_add_tail(&addrw->list, &net->sctp.addr_waitq);
763 
764 	pr_debug("%s: add new entry for cmd:%d, addr:%pISc in wq:%p\n",
765 		 __func__, addrw->state, &addrw->a.sa, &net->sctp.addr_waitq);
766 
767 	if (!timer_pending(&net->sctp.addr_wq_timer)) {
768 		timeo_val = jiffies;
769 		timeo_val += msecs_to_jiffies(SCTP_ADDRESS_TICK_DELAY);
770 		mod_timer(&net->sctp.addr_wq_timer, timeo_val);
771 	}
772 	spin_unlock_bh(&net->sctp.addr_wq_lock);
773 }
774 
775 /* Event handler for inet address addition/deletion events.
776  * The sctp_local_addr_list needs to be protocted by a spin lock since
777  * multiple notifiers (say IPv4 and IPv6) may be running at the same
778  * time and thus corrupt the list.
779  * The reader side is protected with RCU.
780  */
sctp_inetaddr_event(struct notifier_block * this,unsigned long ev,void * ptr)781 static int sctp_inetaddr_event(struct notifier_block *this, unsigned long ev,
782 			       void *ptr)
783 {
784 	struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
785 	struct sctp_sockaddr_entry *addr = NULL;
786 	struct sctp_sockaddr_entry *temp;
787 	struct net *net = dev_net(ifa->ifa_dev->dev);
788 	int found = 0;
789 
790 	switch (ev) {
791 	case NETDEV_UP:
792 		addr = kzalloc(sizeof(*addr), GFP_ATOMIC);
793 		if (addr) {
794 			addr->a.v4.sin_family = AF_INET;
795 			addr->a.v4.sin_addr.s_addr = ifa->ifa_local;
796 			addr->valid = 1;
797 			spin_lock_bh(&net->sctp.local_addr_lock);
798 			list_add_tail_rcu(&addr->list, &net->sctp.local_addr_list);
799 			sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_NEW);
800 			spin_unlock_bh(&net->sctp.local_addr_lock);
801 		}
802 		break;
803 	case NETDEV_DOWN:
804 		spin_lock_bh(&net->sctp.local_addr_lock);
805 		list_for_each_entry_safe(addr, temp,
806 					&net->sctp.local_addr_list, list) {
807 			if (addr->a.sa.sa_family == AF_INET &&
808 					addr->a.v4.sin_addr.s_addr ==
809 					ifa->ifa_local) {
810 				sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_DEL);
811 				found = 1;
812 				addr->valid = 0;
813 				list_del_rcu(&addr->list);
814 				break;
815 			}
816 		}
817 		spin_unlock_bh(&net->sctp.local_addr_lock);
818 		if (found)
819 			kfree_rcu(addr, rcu);
820 		break;
821 	}
822 
823 	return NOTIFY_DONE;
824 }
825 
826 /*
827  * Initialize the control inode/socket with a control endpoint data
828  * structure.  This endpoint is reserved exclusively for the OOTB processing.
829  */
sctp_ctl_sock_init(struct net * net)830 static int sctp_ctl_sock_init(struct net *net)
831 {
832 	int err;
833 	sa_family_t family = PF_INET;
834 
835 	if (sctp_get_pf_specific(PF_INET6))
836 		family = PF_INET6;
837 
838 	err = inet_ctl_sock_create(&net->sctp.ctl_sock, family,
839 				   SOCK_SEQPACKET, IPPROTO_SCTP, net);
840 
841 	/* If IPv6 socket could not be created, try the IPv4 socket */
842 	if (err < 0 && family == PF_INET6)
843 		err = inet_ctl_sock_create(&net->sctp.ctl_sock, AF_INET,
844 					   SOCK_SEQPACKET, IPPROTO_SCTP,
845 					   net);
846 
847 	if (err < 0) {
848 		pr_err("Failed to create the SCTP control socket\n");
849 		return err;
850 	}
851 	return 0;
852 }
853 
sctp_udp_rcv(struct sock * sk,struct sk_buff * skb)854 static int sctp_udp_rcv(struct sock *sk, struct sk_buff *skb)
855 {
856 	SCTP_INPUT_CB(skb)->encap_port = udp_hdr(skb)->source;
857 
858 	skb_set_transport_header(skb, sizeof(struct udphdr));
859 	sctp_rcv(skb);
860 	return 0;
861 }
862 
sctp_udp_sock_start(struct net * net)863 int sctp_udp_sock_start(struct net *net)
864 {
865 	struct udp_tunnel_sock_cfg tuncfg = {NULL};
866 	struct udp_port_cfg udp_conf = {0};
867 	struct socket *sock;
868 	int err;
869 
870 	udp_conf.family = AF_INET;
871 	udp_conf.local_ip.s_addr = htonl(INADDR_ANY);
872 	udp_conf.local_udp_port = htons(net->sctp.udp_port);
873 	err = udp_sock_create(net, &udp_conf, &sock);
874 	if (err) {
875 		pr_err("Failed to create the SCTP UDP tunneling v4 sock\n");
876 		return err;
877 	}
878 
879 	tuncfg.encap_type = 1;
880 	tuncfg.encap_rcv = sctp_udp_rcv;
881 	tuncfg.encap_err_lookup = sctp_udp_v4_err;
882 	setup_udp_tunnel_sock(net, sock, &tuncfg);
883 	net->sctp.udp4_sock = sock->sk;
884 
885 #if IS_ENABLED(CONFIG_IPV6)
886 	memset(&udp_conf, 0, sizeof(udp_conf));
887 
888 	udp_conf.family = AF_INET6;
889 	udp_conf.local_ip6 = in6addr_any;
890 	udp_conf.local_udp_port = htons(net->sctp.udp_port);
891 	udp_conf.use_udp6_rx_checksums = true;
892 	udp_conf.ipv6_v6only = true;
893 	err = udp_sock_create(net, &udp_conf, &sock);
894 	if (err) {
895 		pr_err("Failed to create the SCTP UDP tunneling v6 sock\n");
896 		udp_tunnel_sock_release(net->sctp.udp4_sock->sk_socket);
897 		net->sctp.udp4_sock = NULL;
898 		return err;
899 	}
900 
901 	tuncfg.encap_type = 1;
902 	tuncfg.encap_rcv = sctp_udp_rcv;
903 	tuncfg.encap_err_lookup = sctp_udp_v6_err;
904 	setup_udp_tunnel_sock(net, sock, &tuncfg);
905 	net->sctp.udp6_sock = sock->sk;
906 #endif
907 
908 	return 0;
909 }
910 
sctp_udp_sock_stop(struct net * net)911 void sctp_udp_sock_stop(struct net *net)
912 {
913 	if (net->sctp.udp4_sock) {
914 		udp_tunnel_sock_release(net->sctp.udp4_sock->sk_socket);
915 		net->sctp.udp4_sock = NULL;
916 	}
917 	if (net->sctp.udp6_sock) {
918 		udp_tunnel_sock_release(net->sctp.udp6_sock->sk_socket);
919 		net->sctp.udp6_sock = NULL;
920 	}
921 }
922 
923 /* Register address family specific functions. */
sctp_register_af(struct sctp_af * af)924 int sctp_register_af(struct sctp_af *af)
925 {
926 	switch (af->sa_family) {
927 	case AF_INET:
928 		if (sctp_af_v4_specific)
929 			return 0;
930 		sctp_af_v4_specific = af;
931 		break;
932 	case AF_INET6:
933 		if (sctp_af_v6_specific)
934 			return 0;
935 		sctp_af_v6_specific = af;
936 		break;
937 	default:
938 		return 0;
939 	}
940 
941 	INIT_LIST_HEAD(&af->list);
942 	list_add_tail(&af->list, &sctp_address_families);
943 	return 1;
944 }
945 
946 /* Get the table of functions for manipulating a particular address
947  * family.
948  */
sctp_get_af_specific(sa_family_t family)949 struct sctp_af *sctp_get_af_specific(sa_family_t family)
950 {
951 	switch (family) {
952 	case AF_INET:
953 		return sctp_af_v4_specific;
954 	case AF_INET6:
955 		return sctp_af_v6_specific;
956 	default:
957 		return NULL;
958 	}
959 }
960 
961 /* Common code to initialize a AF_INET msg_name. */
sctp_inet_msgname(char * msgname,int * addr_len)962 static void sctp_inet_msgname(char *msgname, int *addr_len)
963 {
964 	struct sockaddr_in *sin;
965 
966 	sin = (struct sockaddr_in *)msgname;
967 	*addr_len = sizeof(struct sockaddr_in);
968 	sin->sin_family = AF_INET;
969 	memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
970 }
971 
972 /* Copy the primary address of the peer primary address as the msg_name. */
sctp_inet_event_msgname(struct sctp_ulpevent * event,char * msgname,int * addr_len)973 static void sctp_inet_event_msgname(struct sctp_ulpevent *event, char *msgname,
974 				    int *addr_len)
975 {
976 	struct sockaddr_in *sin, *sinfrom;
977 
978 	if (msgname) {
979 		struct sctp_association *asoc;
980 
981 		asoc = event->asoc;
982 		sctp_inet_msgname(msgname, addr_len);
983 		sin = (struct sockaddr_in *)msgname;
984 		sinfrom = &asoc->peer.primary_addr.v4;
985 		sin->sin_port = htons(asoc->peer.port);
986 		sin->sin_addr.s_addr = sinfrom->sin_addr.s_addr;
987 	}
988 }
989 
990 /* Initialize and copy out a msgname from an inbound skb. */
sctp_inet_skb_msgname(struct sk_buff * skb,char * msgname,int * len)991 static void sctp_inet_skb_msgname(struct sk_buff *skb, char *msgname, int *len)
992 {
993 	if (msgname) {
994 		struct sctphdr *sh = sctp_hdr(skb);
995 		struct sockaddr_in *sin = (struct sockaddr_in *)msgname;
996 
997 		sctp_inet_msgname(msgname, len);
998 		sin->sin_port = sh->source;
999 		sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
1000 	}
1001 }
1002 
1003 /* Do we support this AF? */
sctp_inet_af_supported(sa_family_t family,struct sctp_sock * sp)1004 static int sctp_inet_af_supported(sa_family_t family, struct sctp_sock *sp)
1005 {
1006 	/* PF_INET only supports AF_INET addresses. */
1007 	return AF_INET == family;
1008 }
1009 
1010 /* Address matching with wildcards allowed. */
sctp_inet_cmp_addr(const union sctp_addr * addr1,const union sctp_addr * addr2,struct sctp_sock * opt)1011 static int sctp_inet_cmp_addr(const union sctp_addr *addr1,
1012 			      const union sctp_addr *addr2,
1013 			      struct sctp_sock *opt)
1014 {
1015 	/* PF_INET only supports AF_INET addresses. */
1016 	if (addr1->sa.sa_family != addr2->sa.sa_family)
1017 		return 0;
1018 	if (htonl(INADDR_ANY) == addr1->v4.sin_addr.s_addr ||
1019 	    htonl(INADDR_ANY) == addr2->v4.sin_addr.s_addr)
1020 		return 1;
1021 	if (addr1->v4.sin_addr.s_addr == addr2->v4.sin_addr.s_addr)
1022 		return 1;
1023 
1024 	return 0;
1025 }
1026 
1027 /* Verify that provided sockaddr looks bindable.  Common verification has
1028  * already been taken care of.
1029  */
sctp_inet_bind_verify(struct sctp_sock * opt,union sctp_addr * addr)1030 static int sctp_inet_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
1031 {
1032 	return sctp_v4_available(addr, opt);
1033 }
1034 
1035 /* Verify that sockaddr looks sendable.  Common verification has already
1036  * been taken care of.
1037  */
sctp_inet_send_verify(struct sctp_sock * opt,union sctp_addr * addr)1038 static int sctp_inet_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
1039 {
1040 	return 1;
1041 }
1042 
1043 /* Fill in Supported Address Type information for INIT and INIT-ACK
1044  * chunks.  Returns number of addresses supported.
1045  */
sctp_inet_supported_addrs(const struct sctp_sock * opt,__be16 * types)1046 static int sctp_inet_supported_addrs(const struct sctp_sock *opt,
1047 				     __be16 *types)
1048 {
1049 	types[0] = SCTP_PARAM_IPV4_ADDRESS;
1050 	return 1;
1051 }
1052 
1053 /* Wrapper routine that calls the ip transmit routine. */
sctp_v4_xmit(struct sk_buff * skb,struct sctp_transport * t)1054 static inline int sctp_v4_xmit(struct sk_buff *skb, struct sctp_transport *t)
1055 {
1056 	struct dst_entry *dst = dst_clone(t->dst);
1057 	struct flowi4 *fl4 = &t->fl.u.ip4;
1058 	struct sock *sk = skb->sk;
1059 	struct inet_sock *inet = inet_sk(sk);
1060 	__u8 dscp = inet->tos;
1061 	__be16 df = 0;
1062 
1063 	pr_debug("%s: skb:%p, len:%d, src:%pI4, dst:%pI4\n", __func__, skb,
1064 		 skb->len, &fl4->saddr, &fl4->daddr);
1065 
1066 	if (t->dscp & SCTP_DSCP_SET_MASK)
1067 		dscp = t->dscp & SCTP_DSCP_VAL_MASK;
1068 
1069 	inet->pmtudisc = t->param_flags & SPP_PMTUD_ENABLE ? IP_PMTUDISC_DO
1070 							   : IP_PMTUDISC_DONT;
1071 	SCTP_INC_STATS(sock_net(sk), SCTP_MIB_OUTSCTPPACKS);
1072 
1073 	if (!t->encap_port || !sctp_sk(sk)->udp_port) {
1074 		skb_dst_set(skb, dst);
1075 		return __ip_queue_xmit(sk, skb, &t->fl, dscp);
1076 	}
1077 
1078 	if (skb_is_gso(skb))
1079 		skb_shinfo(skb)->gso_type |= SKB_GSO_UDP_TUNNEL_CSUM;
1080 
1081 	if (ip_dont_fragment(sk, dst) && !skb->ignore_df)
1082 		df = htons(IP_DF);
1083 
1084 	skb->encapsulation = 1;
1085 	skb_reset_inner_mac_header(skb);
1086 	skb_reset_inner_transport_header(skb);
1087 	skb_set_inner_ipproto(skb, IPPROTO_SCTP);
1088 	udp_tunnel_xmit_skb((struct rtable *)dst, sk, skb, fl4->saddr,
1089 			    fl4->daddr, dscp, ip4_dst_hoplimit(dst), df,
1090 			    sctp_sk(sk)->udp_port, t->encap_port, false, false);
1091 	return 0;
1092 }
1093 
1094 static struct sctp_af sctp_af_inet;
1095 
1096 static struct sctp_pf sctp_pf_inet = {
1097 	.event_msgname = sctp_inet_event_msgname,
1098 	.skb_msgname   = sctp_inet_skb_msgname,
1099 	.af_supported  = sctp_inet_af_supported,
1100 	.cmp_addr      = sctp_inet_cmp_addr,
1101 	.bind_verify   = sctp_inet_bind_verify,
1102 	.send_verify   = sctp_inet_send_verify,
1103 	.supported_addrs = sctp_inet_supported_addrs,
1104 	.create_accept_sk = sctp_v4_create_accept_sk,
1105 	.addr_to_user  = sctp_v4_addr_to_user,
1106 	.to_sk_saddr   = sctp_v4_to_sk_saddr,
1107 	.to_sk_daddr   = sctp_v4_to_sk_daddr,
1108 	.copy_ip_options = sctp_v4_copy_ip_options,
1109 	.af            = &sctp_af_inet
1110 };
1111 
1112 /* Notifier for inetaddr addition/deletion events.  */
1113 static struct notifier_block sctp_inetaddr_notifier = {
1114 	.notifier_call = sctp_inetaddr_event,
1115 };
1116 
1117 /* Socket operations.  */
1118 static const struct proto_ops inet_seqpacket_ops = {
1119 	.family		   = PF_INET,
1120 	.owner		   = THIS_MODULE,
1121 	.release	   = inet_release,	/* Needs to be wrapped... */
1122 	.bind		   = inet_bind,
1123 	.connect	   = sctp_inet_connect,
1124 	.socketpair	   = sock_no_socketpair,
1125 	.accept		   = inet_accept,
1126 	.getname	   = inet_getname,	/* Semantics are different.  */
1127 	.poll		   = sctp_poll,
1128 	.ioctl		   = inet_ioctl,
1129 	.gettstamp	   = sock_gettstamp,
1130 	.listen		   = sctp_inet_listen,
1131 	.shutdown	   = inet_shutdown,	/* Looks harmless.  */
1132 	.setsockopt	   = sock_common_setsockopt, /* IP_SOL IP_OPTION is a problem */
1133 	.getsockopt	   = sock_common_getsockopt,
1134 	.sendmsg	   = inet_sendmsg,
1135 	.recvmsg	   = inet_recvmsg,
1136 	.mmap		   = sock_no_mmap,
1137 };
1138 
1139 /* Registration with AF_INET family.  */
1140 static struct inet_protosw sctp_seqpacket_protosw = {
1141 	.type       = SOCK_SEQPACKET,
1142 	.protocol   = IPPROTO_SCTP,
1143 	.prot       = &sctp_prot,
1144 	.ops        = &inet_seqpacket_ops,
1145 	.flags      = SCTP_PROTOSW_FLAG
1146 };
1147 static struct inet_protosw sctp_stream_protosw = {
1148 	.type       = SOCK_STREAM,
1149 	.protocol   = IPPROTO_SCTP,
1150 	.prot       = &sctp_prot,
1151 	.ops        = &inet_seqpacket_ops,
1152 	.flags      = SCTP_PROTOSW_FLAG
1153 };
1154 
sctp4_rcv(struct sk_buff * skb)1155 static int sctp4_rcv(struct sk_buff *skb)
1156 {
1157 	SCTP_INPUT_CB(skb)->encap_port = 0;
1158 	return sctp_rcv(skb);
1159 }
1160 
1161 /* Register with IP layer.  */
1162 static const struct net_protocol sctp_protocol = {
1163 	.handler     = sctp4_rcv,
1164 	.err_handler = sctp_v4_err,
1165 	.no_policy   = 1,
1166 	.icmp_strict_tag_validation = 1,
1167 };
1168 
1169 /* IPv4 address related functions.  */
1170 static struct sctp_af sctp_af_inet = {
1171 	.sa_family	   = AF_INET,
1172 	.sctp_xmit	   = sctp_v4_xmit,
1173 	.setsockopt	   = ip_setsockopt,
1174 	.getsockopt	   = ip_getsockopt,
1175 	.get_dst	   = sctp_v4_get_dst,
1176 	.get_saddr	   = sctp_v4_get_saddr,
1177 	.copy_addrlist	   = sctp_v4_copy_addrlist,
1178 	.from_skb	   = sctp_v4_from_skb,
1179 	.from_sk	   = sctp_v4_from_sk,
1180 	.from_addr_param   = sctp_v4_from_addr_param,
1181 	.to_addr_param	   = sctp_v4_to_addr_param,
1182 	.cmp_addr	   = sctp_v4_cmp_addr,
1183 	.addr_valid	   = sctp_v4_addr_valid,
1184 	.inaddr_any	   = sctp_v4_inaddr_any,
1185 	.is_any		   = sctp_v4_is_any,
1186 	.available	   = sctp_v4_available,
1187 	.scope		   = sctp_v4_scope,
1188 	.skb_iif	   = sctp_v4_skb_iif,
1189 	.skb_sdif	   = sctp_v4_skb_sdif,
1190 	.is_ce		   = sctp_v4_is_ce,
1191 	.seq_dump_addr	   = sctp_v4_seq_dump_addr,
1192 	.ecn_capable	   = sctp_v4_ecn_capable,
1193 	.net_header_len	   = sizeof(struct iphdr),
1194 	.sockaddr_len	   = sizeof(struct sockaddr_in),
1195 	.ip_options_len	   = sctp_v4_ip_options_len,
1196 };
1197 
sctp_get_pf_specific(sa_family_t family)1198 struct sctp_pf *sctp_get_pf_specific(sa_family_t family)
1199 {
1200 	switch (family) {
1201 	case PF_INET:
1202 		return sctp_pf_inet_specific;
1203 	case PF_INET6:
1204 		return sctp_pf_inet6_specific;
1205 	default:
1206 		return NULL;
1207 	}
1208 }
1209 
1210 /* Register the PF specific function table.  */
sctp_register_pf(struct sctp_pf * pf,sa_family_t family)1211 int sctp_register_pf(struct sctp_pf *pf, sa_family_t family)
1212 {
1213 	switch (family) {
1214 	case PF_INET:
1215 		if (sctp_pf_inet_specific)
1216 			return 0;
1217 		sctp_pf_inet_specific = pf;
1218 		break;
1219 	case PF_INET6:
1220 		if (sctp_pf_inet6_specific)
1221 			return 0;
1222 		sctp_pf_inet6_specific = pf;
1223 		break;
1224 	default:
1225 		return 0;
1226 	}
1227 	return 1;
1228 }
1229 
init_sctp_mibs(struct net * net)1230 static inline int init_sctp_mibs(struct net *net)
1231 {
1232 	net->sctp.sctp_statistics = alloc_percpu(struct sctp_mib);
1233 	if (!net->sctp.sctp_statistics)
1234 		return -ENOMEM;
1235 	return 0;
1236 }
1237 
cleanup_sctp_mibs(struct net * net)1238 static inline void cleanup_sctp_mibs(struct net *net)
1239 {
1240 	free_percpu(net->sctp.sctp_statistics);
1241 }
1242 
sctp_v4_pf_init(void)1243 static void sctp_v4_pf_init(void)
1244 {
1245 	/* Initialize the SCTP specific PF functions. */
1246 	sctp_register_pf(&sctp_pf_inet, PF_INET);
1247 	sctp_register_af(&sctp_af_inet);
1248 }
1249 
sctp_v4_pf_exit(void)1250 static void sctp_v4_pf_exit(void)
1251 {
1252 	list_del(&sctp_af_inet.list);
1253 }
1254 
sctp_v4_protosw_init(void)1255 static int sctp_v4_protosw_init(void)
1256 {
1257 	int rc;
1258 
1259 	rc = proto_register(&sctp_prot, 1);
1260 	if (rc)
1261 		return rc;
1262 
1263 	/* Register SCTP(UDP and TCP style) with socket layer.  */
1264 	inet_register_protosw(&sctp_seqpacket_protosw);
1265 	inet_register_protosw(&sctp_stream_protosw);
1266 
1267 	return 0;
1268 }
1269 
sctp_v4_protosw_exit(void)1270 static void sctp_v4_protosw_exit(void)
1271 {
1272 	inet_unregister_protosw(&sctp_stream_protosw);
1273 	inet_unregister_protosw(&sctp_seqpacket_protosw);
1274 	proto_unregister(&sctp_prot);
1275 }
1276 
sctp_v4_add_protocol(void)1277 static int sctp_v4_add_protocol(void)
1278 {
1279 	/* Register notifier for inet address additions/deletions. */
1280 	register_inetaddr_notifier(&sctp_inetaddr_notifier);
1281 
1282 	/* Register SCTP with inet layer.  */
1283 	if (inet_add_protocol(&sctp_protocol, IPPROTO_SCTP) < 0)
1284 		return -EAGAIN;
1285 
1286 	return 0;
1287 }
1288 
sctp_v4_del_protocol(void)1289 static void sctp_v4_del_protocol(void)
1290 {
1291 	inet_del_protocol(&sctp_protocol, IPPROTO_SCTP);
1292 	unregister_inetaddr_notifier(&sctp_inetaddr_notifier);
1293 }
1294 
sctp_defaults_init(struct net * net)1295 static int __net_init sctp_defaults_init(struct net *net)
1296 {
1297 	int status;
1298 
1299 	/*
1300 	 * 14. Suggested SCTP Protocol Parameter Values
1301 	 */
1302 	/* The following protocol parameters are RECOMMENDED:  */
1303 	/* RTO.Initial              - 3  seconds */
1304 	net->sctp.rto_initial			= SCTP_RTO_INITIAL;
1305 	/* RTO.Min                  - 1  second */
1306 	net->sctp.rto_min	 		= SCTP_RTO_MIN;
1307 	/* RTO.Max                 -  60 seconds */
1308 	net->sctp.rto_max 			= SCTP_RTO_MAX;
1309 	/* RTO.Alpha                - 1/8 */
1310 	net->sctp.rto_alpha			= SCTP_RTO_ALPHA;
1311 	/* RTO.Beta                 - 1/4 */
1312 	net->sctp.rto_beta			= SCTP_RTO_BETA;
1313 
1314 	/* Valid.Cookie.Life        - 60  seconds */
1315 	net->sctp.valid_cookie_life		= SCTP_DEFAULT_COOKIE_LIFE;
1316 
1317 	/* Whether Cookie Preservative is enabled(1) or not(0) */
1318 	net->sctp.cookie_preserve_enable 	= 1;
1319 
1320 	/* Default sctp sockets to use md5 as their hmac alg */
1321 #if defined (CONFIG_SCTP_DEFAULT_COOKIE_HMAC_MD5)
1322 	net->sctp.sctp_hmac_alg			= "md5";
1323 #elif defined (CONFIG_SCTP_DEFAULT_COOKIE_HMAC_SHA1)
1324 	net->sctp.sctp_hmac_alg			= "sha1";
1325 #else
1326 	net->sctp.sctp_hmac_alg			= NULL;
1327 #endif
1328 
1329 	/* Max.Burst		    - 4 */
1330 	net->sctp.max_burst			= SCTP_DEFAULT_MAX_BURST;
1331 
1332 	/* Disable of Primary Path Switchover by default */
1333 	net->sctp.ps_retrans = SCTP_PS_RETRANS_MAX;
1334 
1335 	/* Enable pf state by default */
1336 	net->sctp.pf_enable = 1;
1337 
1338 	/* Ignore pf exposure feature by default */
1339 	net->sctp.pf_expose = SCTP_PF_EXPOSE_UNSET;
1340 
1341 	/* Association.Max.Retrans  - 10 attempts
1342 	 * Path.Max.Retrans         - 5  attempts (per destination address)
1343 	 * Max.Init.Retransmits     - 8  attempts
1344 	 */
1345 	net->sctp.max_retrans_association	= 10;
1346 	net->sctp.max_retrans_path		= 5;
1347 	net->sctp.max_retrans_init		= 8;
1348 
1349 	/* Sendbuffer growth	    - do per-socket accounting */
1350 	net->sctp.sndbuf_policy			= 0;
1351 
1352 	/* Rcvbuffer growth	    - do per-socket accounting */
1353 	net->sctp.rcvbuf_policy			= 0;
1354 
1355 	/* HB.interval              - 30 seconds */
1356 	net->sctp.hb_interval			= SCTP_DEFAULT_TIMEOUT_HEARTBEAT;
1357 
1358 	/* delayed SACK timeout */
1359 	net->sctp.sack_timeout			= SCTP_DEFAULT_TIMEOUT_SACK;
1360 
1361 	/* Disable ADDIP by default. */
1362 	net->sctp.addip_enable = 0;
1363 	net->sctp.addip_noauth = 0;
1364 	net->sctp.default_auto_asconf = 0;
1365 
1366 	/* Enable PR-SCTP by default. */
1367 	net->sctp.prsctp_enable = 1;
1368 
1369 	/* Disable RECONF by default. */
1370 	net->sctp.reconf_enable = 0;
1371 
1372 	/* Disable AUTH by default. */
1373 	net->sctp.auth_enable = 0;
1374 
1375 	/* Enable ECN by default. */
1376 	net->sctp.ecn_enable = 1;
1377 
1378 	/* Set UDP tunneling listening port to 0 by default */
1379 	net->sctp.udp_port = 0;
1380 
1381 	/* Set remote encap port to 0 by default */
1382 	net->sctp.encap_port = 0;
1383 
1384 	/* Set SCOPE policy to enabled */
1385 	net->sctp.scope_policy = SCTP_SCOPE_POLICY_ENABLE;
1386 
1387 	/* Set the default rwnd update threshold */
1388 	net->sctp.rwnd_upd_shift = SCTP_DEFAULT_RWND_SHIFT;
1389 
1390 	/* Initialize maximum autoclose timeout. */
1391 	net->sctp.max_autoclose		= INT_MAX / HZ;
1392 
1393 #ifdef CONFIG_NET_L3_MASTER_DEV
1394 	net->sctp.l3mdev_accept = 1;
1395 #endif
1396 
1397 	status = sctp_sysctl_net_register(net);
1398 	if (status)
1399 		goto err_sysctl_register;
1400 
1401 	/* Allocate and initialise sctp mibs.  */
1402 	status = init_sctp_mibs(net);
1403 	if (status)
1404 		goto err_init_mibs;
1405 
1406 #ifdef CONFIG_PROC_FS
1407 	/* Initialize proc fs directory.  */
1408 	status = sctp_proc_init(net);
1409 	if (status)
1410 		goto err_init_proc;
1411 #endif
1412 
1413 	sctp_dbg_objcnt_init(net);
1414 
1415 	/* Initialize the local address list. */
1416 	INIT_LIST_HEAD(&net->sctp.local_addr_list);
1417 	spin_lock_init(&net->sctp.local_addr_lock);
1418 	sctp_get_local_addr_list(net);
1419 
1420 	/* Initialize the address event list */
1421 	INIT_LIST_HEAD(&net->sctp.addr_waitq);
1422 	INIT_LIST_HEAD(&net->sctp.auto_asconf_splist);
1423 	spin_lock_init(&net->sctp.addr_wq_lock);
1424 	net->sctp.addr_wq_timer.expires = 0;
1425 	timer_setup(&net->sctp.addr_wq_timer, sctp_addr_wq_timeout_handler, 0);
1426 
1427 	return 0;
1428 
1429 #ifdef CONFIG_PROC_FS
1430 err_init_proc:
1431 	cleanup_sctp_mibs(net);
1432 #endif
1433 err_init_mibs:
1434 	sctp_sysctl_net_unregister(net);
1435 err_sysctl_register:
1436 	return status;
1437 }
1438 
sctp_defaults_exit(struct net * net)1439 static void __net_exit sctp_defaults_exit(struct net *net)
1440 {
1441 	/* Free the local address list */
1442 	sctp_free_addr_wq(net);
1443 	sctp_free_local_addr_list(net);
1444 
1445 #ifdef CONFIG_PROC_FS
1446 	remove_proc_subtree("sctp", net->proc_net);
1447 	net->sctp.proc_net_sctp = NULL;
1448 #endif
1449 	cleanup_sctp_mibs(net);
1450 	sctp_sysctl_net_unregister(net);
1451 }
1452 
1453 static struct pernet_operations sctp_defaults_ops = {
1454 	.init = sctp_defaults_init,
1455 	.exit = sctp_defaults_exit,
1456 };
1457 
sctp_ctrlsock_init(struct net * net)1458 static int __net_init sctp_ctrlsock_init(struct net *net)
1459 {
1460 	int status;
1461 
1462 	/* Initialize the control inode/socket for handling OOTB packets.  */
1463 	status = sctp_ctl_sock_init(net);
1464 	if (status)
1465 		pr_err("Failed to initialize the SCTP control sock\n");
1466 
1467 	return status;
1468 }
1469 
sctp_ctrlsock_exit(struct net * net)1470 static void __net_exit sctp_ctrlsock_exit(struct net *net)
1471 {
1472 	/* Free the control endpoint.  */
1473 	inet_ctl_sock_destroy(net->sctp.ctl_sock);
1474 }
1475 
1476 static struct pernet_operations sctp_ctrlsock_ops = {
1477 	.init = sctp_ctrlsock_init,
1478 	.exit = sctp_ctrlsock_exit,
1479 };
1480 
1481 /* Initialize the universe into something sensible.  */
sctp_init(void)1482 static __init int sctp_init(void)
1483 {
1484 	unsigned long nr_pages = totalram_pages();
1485 	unsigned long limit;
1486 	unsigned long goal;
1487 	int max_entry_order;
1488 	int num_entries;
1489 	int max_share;
1490 	int status;
1491 	int order;
1492 	int i;
1493 
1494 	sock_skb_cb_check_size(sizeof(struct sctp_ulpevent));
1495 
1496 	/* Allocate bind_bucket and chunk caches. */
1497 	status = -ENOBUFS;
1498 	sctp_bucket_cachep = kmem_cache_create("sctp_bind_bucket",
1499 					       sizeof(struct sctp_bind_bucket),
1500 					       0, SLAB_HWCACHE_ALIGN,
1501 					       NULL);
1502 	if (!sctp_bucket_cachep)
1503 		goto out;
1504 
1505 	sctp_chunk_cachep = kmem_cache_create("sctp_chunk",
1506 					       sizeof(struct sctp_chunk),
1507 					       0, SLAB_HWCACHE_ALIGN,
1508 					       NULL);
1509 	if (!sctp_chunk_cachep)
1510 		goto err_chunk_cachep;
1511 
1512 	status = percpu_counter_init(&sctp_sockets_allocated, 0, GFP_KERNEL);
1513 	if (status)
1514 		goto err_percpu_counter_init;
1515 
1516 	/* Implementation specific variables. */
1517 
1518 	/* Initialize default stream count setup information. */
1519 	sctp_max_instreams    		= SCTP_DEFAULT_INSTREAMS;
1520 	sctp_max_outstreams   		= SCTP_DEFAULT_OUTSTREAMS;
1521 
1522 	/* Initialize handle used for association ids. */
1523 	idr_init(&sctp_assocs_id);
1524 
1525 	limit = nr_free_buffer_pages() / 8;
1526 	limit = max(limit, 128UL);
1527 	sysctl_sctp_mem[0] = limit / 4 * 3;
1528 	sysctl_sctp_mem[1] = limit;
1529 	sysctl_sctp_mem[2] = sysctl_sctp_mem[0] * 2;
1530 
1531 	/* Set per-socket limits to no more than 1/128 the pressure threshold*/
1532 	limit = (sysctl_sctp_mem[1]) << (PAGE_SHIFT - 7);
1533 	max_share = min(4UL*1024*1024, limit);
1534 
1535 	sysctl_sctp_rmem[0] = PAGE_SIZE; /* give each asoc 1 page min */
1536 	sysctl_sctp_rmem[1] = 1500 * SKB_TRUESIZE(1);
1537 	sysctl_sctp_rmem[2] = max(sysctl_sctp_rmem[1], max_share);
1538 
1539 	sysctl_sctp_wmem[0] = PAGE_SIZE;
1540 	sysctl_sctp_wmem[1] = 16*1024;
1541 	sysctl_sctp_wmem[2] = max(64*1024, max_share);
1542 
1543 	/* Size and allocate the association hash table.
1544 	 * The methodology is similar to that of the tcp hash tables.
1545 	 * Though not identical.  Start by getting a goal size
1546 	 */
1547 	if (nr_pages >= (128 * 1024))
1548 		goal = nr_pages >> (22 - PAGE_SHIFT);
1549 	else
1550 		goal = nr_pages >> (24 - PAGE_SHIFT);
1551 
1552 	/* Then compute the page order for said goal */
1553 	order = get_order(goal);
1554 
1555 	/* Now compute the required page order for the maximum sized table we
1556 	 * want to create
1557 	 */
1558 	max_entry_order = get_order(MAX_SCTP_PORT_HASH_ENTRIES *
1559 				    sizeof(struct sctp_bind_hashbucket));
1560 
1561 	/* Limit the page order by that maximum hash table size */
1562 	order = min(order, max_entry_order);
1563 
1564 	/* Allocate and initialize the endpoint hash table.  */
1565 	sctp_ep_hashsize = 64;
1566 	sctp_ep_hashtable =
1567 		kmalloc_array(64, sizeof(struct sctp_hashbucket), GFP_KERNEL);
1568 	if (!sctp_ep_hashtable) {
1569 		pr_err("Failed endpoint_hash alloc\n");
1570 		status = -ENOMEM;
1571 		goto err_ehash_alloc;
1572 	}
1573 	for (i = 0; i < sctp_ep_hashsize; i++) {
1574 		rwlock_init(&sctp_ep_hashtable[i].lock);
1575 		INIT_HLIST_HEAD(&sctp_ep_hashtable[i].chain);
1576 	}
1577 
1578 	/* Allocate and initialize the SCTP port hash table.
1579 	 * Note that order is initalized to start at the max sized
1580 	 * table we want to support.  If we can't get that many pages
1581 	 * reduce the order and try again
1582 	 */
1583 	do {
1584 		sctp_port_hashtable = (struct sctp_bind_hashbucket *)
1585 			__get_free_pages(GFP_KERNEL | __GFP_NOWARN, order);
1586 	} while (!sctp_port_hashtable && --order > 0);
1587 
1588 	if (!sctp_port_hashtable) {
1589 		pr_err("Failed bind hash alloc\n");
1590 		status = -ENOMEM;
1591 		goto err_bhash_alloc;
1592 	}
1593 
1594 	/* Now compute the number of entries that will fit in the
1595 	 * port hash space we allocated
1596 	 */
1597 	num_entries = (1UL << order) * PAGE_SIZE /
1598 		      sizeof(struct sctp_bind_hashbucket);
1599 
1600 	/* And finish by rounding it down to the nearest power of two.
1601 	 * This wastes some memory of course, but it's needed because
1602 	 * the hash function operates based on the assumption that
1603 	 * the number of entries is a power of two.
1604 	 */
1605 	sctp_port_hashsize = rounddown_pow_of_two(num_entries);
1606 
1607 	for (i = 0; i < sctp_port_hashsize; i++) {
1608 		spin_lock_init(&sctp_port_hashtable[i].lock);
1609 		INIT_HLIST_HEAD(&sctp_port_hashtable[i].chain);
1610 	}
1611 
1612 	status = sctp_transport_hashtable_init();
1613 	if (status)
1614 		goto err_thash_alloc;
1615 
1616 	pr_info("Hash tables configured (bind %d/%d)\n", sctp_port_hashsize,
1617 		num_entries);
1618 
1619 	sctp_sysctl_register();
1620 
1621 	INIT_LIST_HEAD(&sctp_address_families);
1622 	sctp_v4_pf_init();
1623 	sctp_v6_pf_init();
1624 	sctp_sched_ops_init();
1625 
1626 	status = register_pernet_subsys(&sctp_defaults_ops);
1627 	if (status)
1628 		goto err_register_defaults;
1629 
1630 	status = sctp_v4_protosw_init();
1631 	if (status)
1632 		goto err_protosw_init;
1633 
1634 	status = sctp_v6_protosw_init();
1635 	if (status)
1636 		goto err_v6_protosw_init;
1637 
1638 	status = register_pernet_subsys(&sctp_ctrlsock_ops);
1639 	if (status)
1640 		goto err_register_ctrlsock;
1641 
1642 	status = sctp_v4_add_protocol();
1643 	if (status)
1644 		goto err_add_protocol;
1645 
1646 	/* Register SCTP with inet6 layer.  */
1647 	status = sctp_v6_add_protocol();
1648 	if (status)
1649 		goto err_v6_add_protocol;
1650 
1651 	if (sctp_offload_init() < 0)
1652 		pr_crit("%s: Cannot add SCTP protocol offload\n", __func__);
1653 
1654 out:
1655 	return status;
1656 err_v6_add_protocol:
1657 	sctp_v4_del_protocol();
1658 err_add_protocol:
1659 	unregister_pernet_subsys(&sctp_ctrlsock_ops);
1660 err_register_ctrlsock:
1661 	sctp_v6_protosw_exit();
1662 err_v6_protosw_init:
1663 	sctp_v4_protosw_exit();
1664 err_protosw_init:
1665 	unregister_pernet_subsys(&sctp_defaults_ops);
1666 err_register_defaults:
1667 	sctp_v4_pf_exit();
1668 	sctp_v6_pf_exit();
1669 	sctp_sysctl_unregister();
1670 	free_pages((unsigned long)sctp_port_hashtable,
1671 		   get_order(sctp_port_hashsize *
1672 			     sizeof(struct sctp_bind_hashbucket)));
1673 err_bhash_alloc:
1674 	sctp_transport_hashtable_destroy();
1675 err_thash_alloc:
1676 	kfree(sctp_ep_hashtable);
1677 err_ehash_alloc:
1678 	percpu_counter_destroy(&sctp_sockets_allocated);
1679 err_percpu_counter_init:
1680 	kmem_cache_destroy(sctp_chunk_cachep);
1681 err_chunk_cachep:
1682 	kmem_cache_destroy(sctp_bucket_cachep);
1683 	goto out;
1684 }
1685 
1686 /* Exit handler for the SCTP protocol.  */
sctp_exit(void)1687 static __exit void sctp_exit(void)
1688 {
1689 	/* BUG.  This should probably do something useful like clean
1690 	 * up all the remaining associations and all that memory.
1691 	 */
1692 
1693 	/* Unregister with inet6/inet layers. */
1694 	sctp_v6_del_protocol();
1695 	sctp_v4_del_protocol();
1696 
1697 	unregister_pernet_subsys(&sctp_ctrlsock_ops);
1698 
1699 	/* Free protosw registrations */
1700 	sctp_v6_protosw_exit();
1701 	sctp_v4_protosw_exit();
1702 
1703 	unregister_pernet_subsys(&sctp_defaults_ops);
1704 
1705 	/* Unregister with socket layer. */
1706 	sctp_v6_pf_exit();
1707 	sctp_v4_pf_exit();
1708 
1709 	sctp_sysctl_unregister();
1710 
1711 	free_pages((unsigned long)sctp_port_hashtable,
1712 		   get_order(sctp_port_hashsize *
1713 			     sizeof(struct sctp_bind_hashbucket)));
1714 	kfree(sctp_ep_hashtable);
1715 	sctp_transport_hashtable_destroy();
1716 
1717 	percpu_counter_destroy(&sctp_sockets_allocated);
1718 
1719 	rcu_barrier(); /* Wait for completion of call_rcu()'s */
1720 
1721 	kmem_cache_destroy(sctp_chunk_cachep);
1722 	kmem_cache_destroy(sctp_bucket_cachep);
1723 }
1724 
1725 module_init(sctp_init);
1726 module_exit(sctp_exit);
1727 
1728 /*
1729  * __stringify doesn't likes enums, so use IPPROTO_SCTP value (132) directly.
1730  */
1731 MODULE_ALIAS("net-pf-" __stringify(PF_INET) "-proto-132");
1732 MODULE_ALIAS("net-pf-" __stringify(PF_INET6) "-proto-132");
1733 MODULE_AUTHOR("Linux Kernel SCTP developers <linux-sctp@vger.kernel.org>");
1734 MODULE_DESCRIPTION("Support for the SCTP protocol (RFC2960)");
1735 module_param_named(no_checksums, sctp_checksum_disable, bool, 0644);
1736 MODULE_PARM_DESC(no_checksums, "Disable checksums computing and verification");
1737 MODULE_LICENSE("GPL");
1738