xref: /linux/net/sctp/protocol.c (revision c4c11dd160a8cc98f402c4e12f94b1572e822ffd)
1 /* SCTP kernel implementation
2  * (C) Copyright IBM Corp. 2001, 2004
3  * Copyright (c) 1999-2000 Cisco, Inc.
4  * Copyright (c) 1999-2001 Motorola, Inc.
5  * Copyright (c) 2001 Intel Corp.
6  * Copyright (c) 2001 Nokia, Inc.
7  * Copyright (c) 2001 La Monte H.P. Yarroll
8  *
9  * This file is part of the SCTP kernel implementation
10  *
11  * Initialization/cleanup for SCTP protocol support.
12  *
13  * This SCTP implementation is free software;
14  * you can redistribute it and/or modify it under the terms of
15  * the GNU General Public License as published by
16  * the Free Software Foundation; either version 2, or (at your option)
17  * any later version.
18  *
19  * This SCTP implementation is distributed in the hope that it
20  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
21  *                 ************************
22  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
23  * See the GNU General Public License for more details.
24  *
25  * You should have received a copy of the GNU General Public License
26  * along with GNU CC; see the file COPYING.  If not, write to
27  * the Free Software Foundation, 59 Temple Place - Suite 330,
28  * Boston, MA 02111-1307, USA.
29  *
30  * Please send any bug reports or fixes you make to the
31  * email address(es):
32  *    lksctp developers <lksctp-developers@lists.sourceforge.net>
33  *
34  * Or submit a bug report through the following website:
35  *    http://www.sf.net/projects/lksctp
36  *
37  * Written or modified by:
38  *    La Monte H.P. Yarroll <piggy@acm.org>
39  *    Karl Knutson <karl@athena.chicago.il.us>
40  *    Jon Grimm <jgrimm@us.ibm.com>
41  *    Sridhar Samudrala <sri@us.ibm.com>
42  *    Daisy Chang <daisyc@us.ibm.com>
43  *    Ardelle Fan <ardelle.fan@intel.com>
44  *
45  * Any bugs reported given to us we will try to fix... any fixes shared will
46  * be incorporated into the next SCTP release.
47  */
48 
49 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
50 
51 #include <linux/module.h>
52 #include <linux/init.h>
53 #include <linux/netdevice.h>
54 #include <linux/inetdevice.h>
55 #include <linux/seq_file.h>
56 #include <linux/bootmem.h>
57 #include <linux/highmem.h>
58 #include <linux/swap.h>
59 #include <linux/slab.h>
60 #include <net/net_namespace.h>
61 #include <net/protocol.h>
62 #include <net/ip.h>
63 #include <net/ipv6.h>
64 #include <net/route.h>
65 #include <net/sctp/sctp.h>
66 #include <net/addrconf.h>
67 #include <net/inet_common.h>
68 #include <net/inet_ecn.h>
69 
70 /* Global data structures. */
71 struct sctp_globals sctp_globals __read_mostly;
72 
73 struct idr sctp_assocs_id;
74 DEFINE_SPINLOCK(sctp_assocs_id_lock);
75 
76 static struct sctp_pf *sctp_pf_inet6_specific;
77 static struct sctp_pf *sctp_pf_inet_specific;
78 static struct sctp_af *sctp_af_v4_specific;
79 static struct sctp_af *sctp_af_v6_specific;
80 
81 struct kmem_cache *sctp_chunk_cachep __read_mostly;
82 struct kmem_cache *sctp_bucket_cachep __read_mostly;
83 
84 long sysctl_sctp_mem[3];
85 int sysctl_sctp_rmem[3];
86 int sysctl_sctp_wmem[3];
87 
88 /* Set up the proc fs entry for the SCTP protocol. */
89 static int __net_init sctp_proc_init(struct net *net)
90 {
91 #ifdef CONFIG_PROC_FS
92 	net->sctp.proc_net_sctp = proc_net_mkdir(net, "sctp", net->proc_net);
93 	if (!net->sctp.proc_net_sctp)
94 		goto out_proc_net_sctp;
95 	if (sctp_snmp_proc_init(net))
96 		goto out_snmp_proc_init;
97 	if (sctp_eps_proc_init(net))
98 		goto out_eps_proc_init;
99 	if (sctp_assocs_proc_init(net))
100 		goto out_assocs_proc_init;
101 	if (sctp_remaddr_proc_init(net))
102 		goto out_remaddr_proc_init;
103 
104 	return 0;
105 
106 out_remaddr_proc_init:
107 	sctp_assocs_proc_exit(net);
108 out_assocs_proc_init:
109 	sctp_eps_proc_exit(net);
110 out_eps_proc_init:
111 	sctp_snmp_proc_exit(net);
112 out_snmp_proc_init:
113 	remove_proc_entry("sctp", net->proc_net);
114 	net->sctp.proc_net_sctp = NULL;
115 out_proc_net_sctp:
116 	return -ENOMEM;
117 #endif /* CONFIG_PROC_FS */
118 	return 0;
119 }
120 
121 /* Clean up the proc fs entry for the SCTP protocol.
122  * Note: Do not make this __exit as it is used in the init error
123  * path.
124  */
125 static void sctp_proc_exit(struct net *net)
126 {
127 #ifdef CONFIG_PROC_FS
128 	sctp_snmp_proc_exit(net);
129 	sctp_eps_proc_exit(net);
130 	sctp_assocs_proc_exit(net);
131 	sctp_remaddr_proc_exit(net);
132 
133 	remove_proc_entry("sctp", net->proc_net);
134 	net->sctp.proc_net_sctp = NULL;
135 #endif
136 }
137 
138 /* Private helper to extract ipv4 address and stash them in
139  * the protocol structure.
140  */
141 static void sctp_v4_copy_addrlist(struct list_head *addrlist,
142 				  struct net_device *dev)
143 {
144 	struct in_device *in_dev;
145 	struct in_ifaddr *ifa;
146 	struct sctp_sockaddr_entry *addr;
147 
148 	rcu_read_lock();
149 	if ((in_dev = __in_dev_get_rcu(dev)) == NULL) {
150 		rcu_read_unlock();
151 		return;
152 	}
153 
154 	for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
155 		/* Add the address to the local list.  */
156 		addr = kzalloc(sizeof(*addr), GFP_ATOMIC);
157 		if (addr) {
158 			addr->a.v4.sin_family = AF_INET;
159 			addr->a.v4.sin_port = 0;
160 			addr->a.v4.sin_addr.s_addr = ifa->ifa_local;
161 			addr->valid = 1;
162 			INIT_LIST_HEAD(&addr->list);
163 			list_add_tail(&addr->list, addrlist);
164 		}
165 	}
166 
167 	rcu_read_unlock();
168 }
169 
170 /* Extract our IP addresses from the system and stash them in the
171  * protocol structure.
172  */
173 static void sctp_get_local_addr_list(struct net *net)
174 {
175 	struct net_device *dev;
176 	struct list_head *pos;
177 	struct sctp_af *af;
178 
179 	rcu_read_lock();
180 	for_each_netdev_rcu(net, dev) {
181 		list_for_each(pos, &sctp_address_families) {
182 			af = list_entry(pos, struct sctp_af, list);
183 			af->copy_addrlist(&net->sctp.local_addr_list, dev);
184 		}
185 	}
186 	rcu_read_unlock();
187 }
188 
189 /* Free the existing local addresses.  */
190 static void sctp_free_local_addr_list(struct net *net)
191 {
192 	struct sctp_sockaddr_entry *addr;
193 	struct list_head *pos, *temp;
194 
195 	list_for_each_safe(pos, temp, &net->sctp.local_addr_list) {
196 		addr = list_entry(pos, struct sctp_sockaddr_entry, list);
197 		list_del(pos);
198 		kfree(addr);
199 	}
200 }
201 
202 /* Copy the local addresses which are valid for 'scope' into 'bp'.  */
203 int sctp_copy_local_addr_list(struct net *net, struct sctp_bind_addr *bp,
204 			      sctp_scope_t scope, gfp_t gfp, int copy_flags)
205 {
206 	struct sctp_sockaddr_entry *addr;
207 	int error = 0;
208 
209 	rcu_read_lock();
210 	list_for_each_entry_rcu(addr, &net->sctp.local_addr_list, list) {
211 		if (!addr->valid)
212 			continue;
213 		if (sctp_in_scope(net, &addr->a, scope)) {
214 			/* Now that the address is in scope, check to see if
215 			 * the address type is really supported by the local
216 			 * sock as well as the remote peer.
217 			 */
218 			if ((((AF_INET == addr->a.sa.sa_family) &&
219 			      (copy_flags & SCTP_ADDR4_PEERSUPP))) ||
220 			    (((AF_INET6 == addr->a.sa.sa_family) &&
221 			      (copy_flags & SCTP_ADDR6_ALLOWED) &&
222 			      (copy_flags & SCTP_ADDR6_PEERSUPP)))) {
223 				error = sctp_add_bind_addr(bp, &addr->a,
224 						    SCTP_ADDR_SRC, GFP_ATOMIC);
225 				if (error)
226 					goto end_copy;
227 			}
228 		}
229 	}
230 
231 end_copy:
232 	rcu_read_unlock();
233 	return error;
234 }
235 
236 /* Initialize a sctp_addr from in incoming skb.  */
237 static void sctp_v4_from_skb(union sctp_addr *addr, struct sk_buff *skb,
238 			     int is_saddr)
239 {
240 	void *from;
241 	__be16 *port;
242 	struct sctphdr *sh;
243 
244 	port = &addr->v4.sin_port;
245 	addr->v4.sin_family = AF_INET;
246 
247 	sh = sctp_hdr(skb);
248 	if (is_saddr) {
249 		*port  = sh->source;
250 		from = &ip_hdr(skb)->saddr;
251 	} else {
252 		*port = sh->dest;
253 		from = &ip_hdr(skb)->daddr;
254 	}
255 	memcpy(&addr->v4.sin_addr.s_addr, from, sizeof(struct in_addr));
256 }
257 
258 /* Initialize an sctp_addr from a socket. */
259 static void sctp_v4_from_sk(union sctp_addr *addr, struct sock *sk)
260 {
261 	addr->v4.sin_family = AF_INET;
262 	addr->v4.sin_port = 0;
263 	addr->v4.sin_addr.s_addr = inet_sk(sk)->inet_rcv_saddr;
264 }
265 
266 /* Initialize sk->sk_rcv_saddr from sctp_addr. */
267 static void sctp_v4_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
268 {
269 	inet_sk(sk)->inet_rcv_saddr = addr->v4.sin_addr.s_addr;
270 }
271 
272 /* Initialize sk->sk_daddr from sctp_addr. */
273 static void sctp_v4_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
274 {
275 	inet_sk(sk)->inet_daddr = addr->v4.sin_addr.s_addr;
276 }
277 
278 /* Initialize a sctp_addr from an address parameter. */
279 static void sctp_v4_from_addr_param(union sctp_addr *addr,
280 				    union sctp_addr_param *param,
281 				    __be16 port, int iif)
282 {
283 	addr->v4.sin_family = AF_INET;
284 	addr->v4.sin_port = port;
285 	addr->v4.sin_addr.s_addr = param->v4.addr.s_addr;
286 }
287 
288 /* Initialize an address parameter from a sctp_addr and return the length
289  * of the address parameter.
290  */
291 static int sctp_v4_to_addr_param(const union sctp_addr *addr,
292 				 union sctp_addr_param *param)
293 {
294 	int length = sizeof(sctp_ipv4addr_param_t);
295 
296 	param->v4.param_hdr.type = SCTP_PARAM_IPV4_ADDRESS;
297 	param->v4.param_hdr.length = htons(length);
298 	param->v4.addr.s_addr = addr->v4.sin_addr.s_addr;
299 
300 	return length;
301 }
302 
303 /* Initialize a sctp_addr from a dst_entry. */
304 static void sctp_v4_dst_saddr(union sctp_addr *saddr, struct flowi4 *fl4,
305 			      __be16 port)
306 {
307 	saddr->v4.sin_family = AF_INET;
308 	saddr->v4.sin_port = port;
309 	saddr->v4.sin_addr.s_addr = fl4->saddr;
310 }
311 
312 /* Compare two addresses exactly. */
313 static int sctp_v4_cmp_addr(const union sctp_addr *addr1,
314 			    const union sctp_addr *addr2)
315 {
316 	if (addr1->sa.sa_family != addr2->sa.sa_family)
317 		return 0;
318 	if (addr1->v4.sin_port != addr2->v4.sin_port)
319 		return 0;
320 	if (addr1->v4.sin_addr.s_addr != addr2->v4.sin_addr.s_addr)
321 		return 0;
322 
323 	return 1;
324 }
325 
326 /* Initialize addr struct to INADDR_ANY. */
327 static void sctp_v4_inaddr_any(union sctp_addr *addr, __be16 port)
328 {
329 	addr->v4.sin_family = AF_INET;
330 	addr->v4.sin_addr.s_addr = htonl(INADDR_ANY);
331 	addr->v4.sin_port = port;
332 }
333 
334 /* Is this a wildcard address? */
335 static int sctp_v4_is_any(const union sctp_addr *addr)
336 {
337 	return htonl(INADDR_ANY) == addr->v4.sin_addr.s_addr;
338 }
339 
340 /* This function checks if the address is a valid address to be used for
341  * SCTP binding.
342  *
343  * Output:
344  * Return 0 - If the address is a non-unicast or an illegal address.
345  * Return 1 - If the address is a unicast.
346  */
347 static int sctp_v4_addr_valid(union sctp_addr *addr,
348 			      struct sctp_sock *sp,
349 			      const struct sk_buff *skb)
350 {
351 	/* IPv4 addresses not allowed */
352 	if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
353 		return 0;
354 
355 	/* Is this a non-unicast address or a unusable SCTP address? */
356 	if (IS_IPV4_UNUSABLE_ADDRESS(addr->v4.sin_addr.s_addr))
357 		return 0;
358 
359 	/* Is this a broadcast address? */
360 	if (skb && skb_rtable(skb)->rt_flags & RTCF_BROADCAST)
361 		return 0;
362 
363 	return 1;
364 }
365 
366 /* Should this be available for binding?   */
367 static int sctp_v4_available(union sctp_addr *addr, struct sctp_sock *sp)
368 {
369 	struct net *net = sock_net(&sp->inet.sk);
370 	int ret = inet_addr_type(net, addr->v4.sin_addr.s_addr);
371 
372 
373 	if (addr->v4.sin_addr.s_addr != htonl(INADDR_ANY) &&
374 	   ret != RTN_LOCAL &&
375 	   !sp->inet.freebind &&
376 	   !sysctl_ip_nonlocal_bind)
377 		return 0;
378 
379 	if (ipv6_only_sock(sctp_opt2sk(sp)))
380 		return 0;
381 
382 	return 1;
383 }
384 
385 /* Checking the loopback, private and other address scopes as defined in
386  * RFC 1918.   The IPv4 scoping is based on the draft for SCTP IPv4
387  * scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>.
388  *
389  * Level 0 - unusable SCTP addresses
390  * Level 1 - loopback address
391  * Level 2 - link-local addresses
392  * Level 3 - private addresses.
393  * Level 4 - global addresses
394  * For INIT and INIT-ACK address list, let L be the level of
395  * of requested destination address, sender and receiver
396  * SHOULD include all of its addresses with level greater
397  * than or equal to L.
398  *
399  * IPv4 scoping can be controlled through sysctl option
400  * net.sctp.addr_scope_policy
401  */
402 static sctp_scope_t sctp_v4_scope(union sctp_addr *addr)
403 {
404 	sctp_scope_t retval;
405 
406 	/* Check for unusable SCTP addresses. */
407 	if (IS_IPV4_UNUSABLE_ADDRESS(addr->v4.sin_addr.s_addr)) {
408 		retval =  SCTP_SCOPE_UNUSABLE;
409 	} else if (ipv4_is_loopback(addr->v4.sin_addr.s_addr)) {
410 		retval = SCTP_SCOPE_LOOPBACK;
411 	} else if (ipv4_is_linklocal_169(addr->v4.sin_addr.s_addr)) {
412 		retval = SCTP_SCOPE_LINK;
413 	} else if (ipv4_is_private_10(addr->v4.sin_addr.s_addr) ||
414 		   ipv4_is_private_172(addr->v4.sin_addr.s_addr) ||
415 		   ipv4_is_private_192(addr->v4.sin_addr.s_addr)) {
416 		retval = SCTP_SCOPE_PRIVATE;
417 	} else {
418 		retval = SCTP_SCOPE_GLOBAL;
419 	}
420 
421 	return retval;
422 }
423 
424 /* Returns a valid dst cache entry for the given source and destination ip
425  * addresses. If an association is passed, trys to get a dst entry with a
426  * source address that matches an address in the bind address list.
427  */
428 static void sctp_v4_get_dst(struct sctp_transport *t, union sctp_addr *saddr,
429 				struct flowi *fl, struct sock *sk)
430 {
431 	struct sctp_association *asoc = t->asoc;
432 	struct rtable *rt;
433 	struct flowi4 *fl4 = &fl->u.ip4;
434 	struct sctp_bind_addr *bp;
435 	struct sctp_sockaddr_entry *laddr;
436 	struct dst_entry *dst = NULL;
437 	union sctp_addr *daddr = &t->ipaddr;
438 	union sctp_addr dst_saddr;
439 
440 	memset(fl4, 0x0, sizeof(struct flowi4));
441 	fl4->daddr  = daddr->v4.sin_addr.s_addr;
442 	fl4->fl4_dport = daddr->v4.sin_port;
443 	fl4->flowi4_proto = IPPROTO_SCTP;
444 	if (asoc) {
445 		fl4->flowi4_tos = RT_CONN_FLAGS(asoc->base.sk);
446 		fl4->flowi4_oif = asoc->base.sk->sk_bound_dev_if;
447 		fl4->fl4_sport = htons(asoc->base.bind_addr.port);
448 	}
449 	if (saddr) {
450 		fl4->saddr = saddr->v4.sin_addr.s_addr;
451 		fl4->fl4_sport = saddr->v4.sin_port;
452 	}
453 
454 	pr_debug("%s: dst:%pI4, src:%pI4 - ", __func__, &fl4->daddr,
455 		 &fl4->saddr);
456 
457 	rt = ip_route_output_key(sock_net(sk), fl4);
458 	if (!IS_ERR(rt))
459 		dst = &rt->dst;
460 
461 	/* If there is no association or if a source address is passed, no
462 	 * more validation is required.
463 	 */
464 	if (!asoc || saddr)
465 		goto out;
466 
467 	bp = &asoc->base.bind_addr;
468 
469 	if (dst) {
470 		/* Walk through the bind address list and look for a bind
471 		 * address that matches the source address of the returned dst.
472 		 */
473 		sctp_v4_dst_saddr(&dst_saddr, fl4, htons(bp->port));
474 		rcu_read_lock();
475 		list_for_each_entry_rcu(laddr, &bp->address_list, list) {
476 			if (!laddr->valid || (laddr->state == SCTP_ADDR_DEL) ||
477 			    (laddr->state != SCTP_ADDR_SRC &&
478 			    !asoc->src_out_of_asoc_ok))
479 				continue;
480 			if (sctp_v4_cmp_addr(&dst_saddr, &laddr->a))
481 				goto out_unlock;
482 		}
483 		rcu_read_unlock();
484 
485 		/* None of the bound addresses match the source address of the
486 		 * dst. So release it.
487 		 */
488 		dst_release(dst);
489 		dst = NULL;
490 	}
491 
492 	/* Walk through the bind address list and try to get a dst that
493 	 * matches a bind address as the source address.
494 	 */
495 	rcu_read_lock();
496 	list_for_each_entry_rcu(laddr, &bp->address_list, list) {
497 		if (!laddr->valid)
498 			continue;
499 		if ((laddr->state == SCTP_ADDR_SRC) &&
500 		    (AF_INET == laddr->a.sa.sa_family)) {
501 			fl4->saddr = laddr->a.v4.sin_addr.s_addr;
502 			fl4->fl4_sport = laddr->a.v4.sin_port;
503 			rt = ip_route_output_key(sock_net(sk), fl4);
504 			if (!IS_ERR(rt)) {
505 				dst = &rt->dst;
506 				goto out_unlock;
507 			}
508 		}
509 	}
510 
511 out_unlock:
512 	rcu_read_unlock();
513 out:
514 	t->dst = dst;
515 	if (dst)
516 		pr_debug("rt_dst:%pI4, rt_src:%pI4\n",
517 			 &fl4->daddr, &fl4->saddr);
518 	else
519 		pr_debug("no route\n");
520 }
521 
522 /* For v4, the source address is cached in the route entry(dst). So no need
523  * to cache it separately and hence this is an empty routine.
524  */
525 static void sctp_v4_get_saddr(struct sctp_sock *sk,
526 			      struct sctp_transport *t,
527 			      struct flowi *fl)
528 {
529 	union sctp_addr *saddr = &t->saddr;
530 	struct rtable *rt = (struct rtable *)t->dst;
531 
532 	if (rt) {
533 		saddr->v4.sin_family = AF_INET;
534 		saddr->v4.sin_addr.s_addr = fl->u.ip4.saddr;
535 	}
536 }
537 
538 /* What interface did this skb arrive on? */
539 static int sctp_v4_skb_iif(const struct sk_buff *skb)
540 {
541 	return inet_iif(skb);
542 }
543 
544 /* Was this packet marked by Explicit Congestion Notification? */
545 static int sctp_v4_is_ce(const struct sk_buff *skb)
546 {
547 	return INET_ECN_is_ce(ip_hdr(skb)->tos);
548 }
549 
550 /* Create and initialize a new sk for the socket returned by accept(). */
551 static struct sock *sctp_v4_create_accept_sk(struct sock *sk,
552 					     struct sctp_association *asoc)
553 {
554 	struct sock *newsk = sk_alloc(sock_net(sk), PF_INET, GFP_KERNEL,
555 			sk->sk_prot);
556 	struct inet_sock *newinet;
557 
558 	if (!newsk)
559 		goto out;
560 
561 	sock_init_data(NULL, newsk);
562 
563 	sctp_copy_sock(newsk, sk, asoc);
564 	sock_reset_flag(newsk, SOCK_ZAPPED);
565 
566 	newinet = inet_sk(newsk);
567 
568 	newinet->inet_daddr = asoc->peer.primary_addr.v4.sin_addr.s_addr;
569 
570 	sk_refcnt_debug_inc(newsk);
571 
572 	if (newsk->sk_prot->init(newsk)) {
573 		sk_common_release(newsk);
574 		newsk = NULL;
575 	}
576 
577 out:
578 	return newsk;
579 }
580 
581 /* Map address, empty for v4 family */
582 static void sctp_v4_addr_v4map(struct sctp_sock *sp, union sctp_addr *addr)
583 {
584 	/* Empty */
585 }
586 
587 /* Dump the v4 addr to the seq file. */
588 static void sctp_v4_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
589 {
590 	seq_printf(seq, "%pI4 ", &addr->v4.sin_addr);
591 }
592 
593 static void sctp_v4_ecn_capable(struct sock *sk)
594 {
595 	INET_ECN_xmit(sk);
596 }
597 
598 static void sctp_addr_wq_timeout_handler(unsigned long arg)
599 {
600 	struct net *net = (struct net *)arg;
601 	struct sctp_sockaddr_entry *addrw, *temp;
602 	struct sctp_sock *sp;
603 
604 	spin_lock_bh(&net->sctp.addr_wq_lock);
605 
606 	list_for_each_entry_safe(addrw, temp, &net->sctp.addr_waitq, list) {
607 		pr_debug("%s: the first ent in wq:%p is addr:%pISc for cmd:%d at "
608 			 "entry:%p\n", __func__, &net->sctp.addr_waitq, &addrw->a.sa,
609 			 addrw->state, addrw);
610 
611 #if IS_ENABLED(CONFIG_IPV6)
612 		/* Now we send an ASCONF for each association */
613 		/* Note. we currently don't handle link local IPv6 addressees */
614 		if (addrw->a.sa.sa_family == AF_INET6) {
615 			struct in6_addr *in6;
616 
617 			if (ipv6_addr_type(&addrw->a.v6.sin6_addr) &
618 			    IPV6_ADDR_LINKLOCAL)
619 				goto free_next;
620 
621 			in6 = (struct in6_addr *)&addrw->a.v6.sin6_addr;
622 			if (ipv6_chk_addr(net, in6, NULL, 0) == 0 &&
623 			    addrw->state == SCTP_ADDR_NEW) {
624 				unsigned long timeo_val;
625 
626 				pr_debug("%s: this is on DAD, trying %d sec "
627 					 "later\n", __func__,
628 					 SCTP_ADDRESS_TICK_DELAY);
629 
630 				timeo_val = jiffies;
631 				timeo_val += msecs_to_jiffies(SCTP_ADDRESS_TICK_DELAY);
632 				mod_timer(&net->sctp.addr_wq_timer, timeo_val);
633 				break;
634 			}
635 		}
636 #endif
637 		list_for_each_entry(sp, &net->sctp.auto_asconf_splist, auto_asconf_list) {
638 			struct sock *sk;
639 
640 			sk = sctp_opt2sk(sp);
641 			/* ignore bound-specific endpoints */
642 			if (!sctp_is_ep_boundall(sk))
643 				continue;
644 			sctp_bh_lock_sock(sk);
645 			if (sctp_asconf_mgmt(sp, addrw) < 0)
646 				pr_debug("%s: sctp_asconf_mgmt failed\n", __func__);
647 			sctp_bh_unlock_sock(sk);
648 		}
649 #if IS_ENABLED(CONFIG_IPV6)
650 free_next:
651 #endif
652 		list_del(&addrw->list);
653 		kfree(addrw);
654 	}
655 	spin_unlock_bh(&net->sctp.addr_wq_lock);
656 }
657 
658 static void sctp_free_addr_wq(struct net *net)
659 {
660 	struct sctp_sockaddr_entry *addrw;
661 	struct sctp_sockaddr_entry *temp;
662 
663 	spin_lock_bh(&net->sctp.addr_wq_lock);
664 	del_timer(&net->sctp.addr_wq_timer);
665 	list_for_each_entry_safe(addrw, temp, &net->sctp.addr_waitq, list) {
666 		list_del(&addrw->list);
667 		kfree(addrw);
668 	}
669 	spin_unlock_bh(&net->sctp.addr_wq_lock);
670 }
671 
672 /* lookup the entry for the same address in the addr_waitq
673  * sctp_addr_wq MUST be locked
674  */
675 static struct sctp_sockaddr_entry *sctp_addr_wq_lookup(struct net *net,
676 					struct sctp_sockaddr_entry *addr)
677 {
678 	struct sctp_sockaddr_entry *addrw;
679 
680 	list_for_each_entry(addrw, &net->sctp.addr_waitq, list) {
681 		if (addrw->a.sa.sa_family != addr->a.sa.sa_family)
682 			continue;
683 		if (addrw->a.sa.sa_family == AF_INET) {
684 			if (addrw->a.v4.sin_addr.s_addr ==
685 			    addr->a.v4.sin_addr.s_addr)
686 				return addrw;
687 		} else if (addrw->a.sa.sa_family == AF_INET6) {
688 			if (ipv6_addr_equal(&addrw->a.v6.sin6_addr,
689 			    &addr->a.v6.sin6_addr))
690 				return addrw;
691 		}
692 	}
693 	return NULL;
694 }
695 
696 void sctp_addr_wq_mgmt(struct net *net, struct sctp_sockaddr_entry *addr, int cmd)
697 {
698 	struct sctp_sockaddr_entry *addrw;
699 	unsigned long timeo_val;
700 
701 	/* first, we check if an opposite message already exist in the queue.
702 	 * If we found such message, it is removed.
703 	 * This operation is a bit stupid, but the DHCP client attaches the
704 	 * new address after a couple of addition and deletion of that address
705 	 */
706 
707 	spin_lock_bh(&net->sctp.addr_wq_lock);
708 	/* Offsets existing events in addr_wq */
709 	addrw = sctp_addr_wq_lookup(net, addr);
710 	if (addrw) {
711 		if (addrw->state != cmd) {
712 			pr_debug("%s: offsets existing entry for %d, addr:%pISc "
713 				 "in wq:%p\n", __func__, addrw->state, &addrw->a.sa,
714 				 &net->sctp.addr_waitq);
715 
716 			list_del(&addrw->list);
717 			kfree(addrw);
718 		}
719 		spin_unlock_bh(&net->sctp.addr_wq_lock);
720 		return;
721 	}
722 
723 	/* OK, we have to add the new address to the wait queue */
724 	addrw = kmemdup(addr, sizeof(struct sctp_sockaddr_entry), GFP_ATOMIC);
725 	if (addrw == NULL) {
726 		spin_unlock_bh(&net->sctp.addr_wq_lock);
727 		return;
728 	}
729 	addrw->state = cmd;
730 	list_add_tail(&addrw->list, &net->sctp.addr_waitq);
731 
732 	pr_debug("%s: add new entry for cmd:%d, addr:%pISc in wq:%p\n",
733 		 __func__, addrw->state, &addrw->a.sa, &net->sctp.addr_waitq);
734 
735 	if (!timer_pending(&net->sctp.addr_wq_timer)) {
736 		timeo_val = jiffies;
737 		timeo_val += msecs_to_jiffies(SCTP_ADDRESS_TICK_DELAY);
738 		mod_timer(&net->sctp.addr_wq_timer, timeo_val);
739 	}
740 	spin_unlock_bh(&net->sctp.addr_wq_lock);
741 }
742 
743 /* Event handler for inet address addition/deletion events.
744  * The sctp_local_addr_list needs to be protocted by a spin lock since
745  * multiple notifiers (say IPv4 and IPv6) may be running at the same
746  * time and thus corrupt the list.
747  * The reader side is protected with RCU.
748  */
749 static int sctp_inetaddr_event(struct notifier_block *this, unsigned long ev,
750 			       void *ptr)
751 {
752 	struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
753 	struct sctp_sockaddr_entry *addr = NULL;
754 	struct sctp_sockaddr_entry *temp;
755 	struct net *net = dev_net(ifa->ifa_dev->dev);
756 	int found = 0;
757 
758 	switch (ev) {
759 	case NETDEV_UP:
760 		addr = kmalloc(sizeof(struct sctp_sockaddr_entry), GFP_ATOMIC);
761 		if (addr) {
762 			addr->a.v4.sin_family = AF_INET;
763 			addr->a.v4.sin_port = 0;
764 			addr->a.v4.sin_addr.s_addr = ifa->ifa_local;
765 			addr->valid = 1;
766 			spin_lock_bh(&net->sctp.local_addr_lock);
767 			list_add_tail_rcu(&addr->list, &net->sctp.local_addr_list);
768 			sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_NEW);
769 			spin_unlock_bh(&net->sctp.local_addr_lock);
770 		}
771 		break;
772 	case NETDEV_DOWN:
773 		spin_lock_bh(&net->sctp.local_addr_lock);
774 		list_for_each_entry_safe(addr, temp,
775 					&net->sctp.local_addr_list, list) {
776 			if (addr->a.sa.sa_family == AF_INET &&
777 					addr->a.v4.sin_addr.s_addr ==
778 					ifa->ifa_local) {
779 				sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_DEL);
780 				found = 1;
781 				addr->valid = 0;
782 				list_del_rcu(&addr->list);
783 				break;
784 			}
785 		}
786 		spin_unlock_bh(&net->sctp.local_addr_lock);
787 		if (found)
788 			kfree_rcu(addr, rcu);
789 		break;
790 	}
791 
792 	return NOTIFY_DONE;
793 }
794 
795 /*
796  * Initialize the control inode/socket with a control endpoint data
797  * structure.  This endpoint is reserved exclusively for the OOTB processing.
798  */
799 static int sctp_ctl_sock_init(struct net *net)
800 {
801 	int err;
802 	sa_family_t family = PF_INET;
803 
804 	if (sctp_get_pf_specific(PF_INET6))
805 		family = PF_INET6;
806 
807 	err = inet_ctl_sock_create(&net->sctp.ctl_sock, family,
808 				   SOCK_SEQPACKET, IPPROTO_SCTP, net);
809 
810 	/* If IPv6 socket could not be created, try the IPv4 socket */
811 	if (err < 0 && family == PF_INET6)
812 		err = inet_ctl_sock_create(&net->sctp.ctl_sock, AF_INET,
813 					   SOCK_SEQPACKET, IPPROTO_SCTP,
814 					   net);
815 
816 	if (err < 0) {
817 		pr_err("Failed to create the SCTP control socket\n");
818 		return err;
819 	}
820 	return 0;
821 }
822 
823 /* Register address family specific functions. */
824 int sctp_register_af(struct sctp_af *af)
825 {
826 	switch (af->sa_family) {
827 	case AF_INET:
828 		if (sctp_af_v4_specific)
829 			return 0;
830 		sctp_af_v4_specific = af;
831 		break;
832 	case AF_INET6:
833 		if (sctp_af_v6_specific)
834 			return 0;
835 		sctp_af_v6_specific = af;
836 		break;
837 	default:
838 		return 0;
839 	}
840 
841 	INIT_LIST_HEAD(&af->list);
842 	list_add_tail(&af->list, &sctp_address_families);
843 	return 1;
844 }
845 
846 /* Get the table of functions for manipulating a particular address
847  * family.
848  */
849 struct sctp_af *sctp_get_af_specific(sa_family_t family)
850 {
851 	switch (family) {
852 	case AF_INET:
853 		return sctp_af_v4_specific;
854 	case AF_INET6:
855 		return sctp_af_v6_specific;
856 	default:
857 		return NULL;
858 	}
859 }
860 
861 /* Common code to initialize a AF_INET msg_name. */
862 static void sctp_inet_msgname(char *msgname, int *addr_len)
863 {
864 	struct sockaddr_in *sin;
865 
866 	sin = (struct sockaddr_in *)msgname;
867 	*addr_len = sizeof(struct sockaddr_in);
868 	sin->sin_family = AF_INET;
869 	memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
870 }
871 
872 /* Copy the primary address of the peer primary address as the msg_name. */
873 static void sctp_inet_event_msgname(struct sctp_ulpevent *event, char *msgname,
874 				    int *addr_len)
875 {
876 	struct sockaddr_in *sin, *sinfrom;
877 
878 	if (msgname) {
879 		struct sctp_association *asoc;
880 
881 		asoc = event->asoc;
882 		sctp_inet_msgname(msgname, addr_len);
883 		sin = (struct sockaddr_in *)msgname;
884 		sinfrom = &asoc->peer.primary_addr.v4;
885 		sin->sin_port = htons(asoc->peer.port);
886 		sin->sin_addr.s_addr = sinfrom->sin_addr.s_addr;
887 	}
888 }
889 
890 /* Initialize and copy out a msgname from an inbound skb. */
891 static void sctp_inet_skb_msgname(struct sk_buff *skb, char *msgname, int *len)
892 {
893 	if (msgname) {
894 		struct sctphdr *sh = sctp_hdr(skb);
895 		struct sockaddr_in *sin = (struct sockaddr_in *)msgname;
896 
897 		sctp_inet_msgname(msgname, len);
898 		sin->sin_port = sh->source;
899 		sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
900 	}
901 }
902 
903 /* Do we support this AF? */
904 static int sctp_inet_af_supported(sa_family_t family, struct sctp_sock *sp)
905 {
906 	/* PF_INET only supports AF_INET addresses. */
907 	return AF_INET == family;
908 }
909 
910 /* Address matching with wildcards allowed. */
911 static int sctp_inet_cmp_addr(const union sctp_addr *addr1,
912 			      const union sctp_addr *addr2,
913 			      struct sctp_sock *opt)
914 {
915 	/* PF_INET only supports AF_INET addresses. */
916 	if (addr1->sa.sa_family != addr2->sa.sa_family)
917 		return 0;
918 	if (htonl(INADDR_ANY) == addr1->v4.sin_addr.s_addr ||
919 	    htonl(INADDR_ANY) == addr2->v4.sin_addr.s_addr)
920 		return 1;
921 	if (addr1->v4.sin_addr.s_addr == addr2->v4.sin_addr.s_addr)
922 		return 1;
923 
924 	return 0;
925 }
926 
927 /* Verify that provided sockaddr looks bindable.  Common verification has
928  * already been taken care of.
929  */
930 static int sctp_inet_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
931 {
932 	return sctp_v4_available(addr, opt);
933 }
934 
935 /* Verify that sockaddr looks sendable.  Common verification has already
936  * been taken care of.
937  */
938 static int sctp_inet_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
939 {
940 	return 1;
941 }
942 
943 /* Fill in Supported Address Type information for INIT and INIT-ACK
944  * chunks.  Returns number of addresses supported.
945  */
946 static int sctp_inet_supported_addrs(const struct sctp_sock *opt,
947 				     __be16 *types)
948 {
949 	types[0] = SCTP_PARAM_IPV4_ADDRESS;
950 	return 1;
951 }
952 
953 /* Wrapper routine that calls the ip transmit routine. */
954 static inline int sctp_v4_xmit(struct sk_buff *skb,
955 			       struct sctp_transport *transport)
956 {
957 	struct inet_sock *inet = inet_sk(skb->sk);
958 
959 	pr_debug("%s: skb:%p, len:%d, src:%pI4, dst:%pI4\n", __func__, skb,
960 		 skb->len, &transport->fl.u.ip4.saddr, &transport->fl.u.ip4.daddr);
961 
962 	inet->pmtudisc = transport->param_flags & SPP_PMTUD_ENABLE ?
963 			 IP_PMTUDISC_DO : IP_PMTUDISC_DONT;
964 
965 	SCTP_INC_STATS(sock_net(&inet->sk), SCTP_MIB_OUTSCTPPACKS);
966 
967 	return ip_queue_xmit(skb, &transport->fl);
968 }
969 
970 static struct sctp_af sctp_af_inet;
971 
972 static struct sctp_pf sctp_pf_inet = {
973 	.event_msgname = sctp_inet_event_msgname,
974 	.skb_msgname   = sctp_inet_skb_msgname,
975 	.af_supported  = sctp_inet_af_supported,
976 	.cmp_addr      = sctp_inet_cmp_addr,
977 	.bind_verify   = sctp_inet_bind_verify,
978 	.send_verify   = sctp_inet_send_verify,
979 	.supported_addrs = sctp_inet_supported_addrs,
980 	.create_accept_sk = sctp_v4_create_accept_sk,
981 	.addr_v4map	= sctp_v4_addr_v4map,
982 	.af            = &sctp_af_inet
983 };
984 
985 /* Notifier for inetaddr addition/deletion events.  */
986 static struct notifier_block sctp_inetaddr_notifier = {
987 	.notifier_call = sctp_inetaddr_event,
988 };
989 
990 /* Socket operations.  */
991 static const struct proto_ops inet_seqpacket_ops = {
992 	.family		   = PF_INET,
993 	.owner		   = THIS_MODULE,
994 	.release	   = inet_release,	/* Needs to be wrapped... */
995 	.bind		   = inet_bind,
996 	.connect	   = inet_dgram_connect,
997 	.socketpair	   = sock_no_socketpair,
998 	.accept		   = inet_accept,
999 	.getname	   = inet_getname,	/* Semantics are different.  */
1000 	.poll		   = sctp_poll,
1001 	.ioctl		   = inet_ioctl,
1002 	.listen		   = sctp_inet_listen,
1003 	.shutdown	   = inet_shutdown,	/* Looks harmless.  */
1004 	.setsockopt	   = sock_common_setsockopt, /* IP_SOL IP_OPTION is a problem */
1005 	.getsockopt	   = sock_common_getsockopt,
1006 	.sendmsg	   = inet_sendmsg,
1007 	.recvmsg	   = sock_common_recvmsg,
1008 	.mmap		   = sock_no_mmap,
1009 	.sendpage	   = sock_no_sendpage,
1010 #ifdef CONFIG_COMPAT
1011 	.compat_setsockopt = compat_sock_common_setsockopt,
1012 	.compat_getsockopt = compat_sock_common_getsockopt,
1013 #endif
1014 };
1015 
1016 /* Registration with AF_INET family.  */
1017 static struct inet_protosw sctp_seqpacket_protosw = {
1018 	.type       = SOCK_SEQPACKET,
1019 	.protocol   = IPPROTO_SCTP,
1020 	.prot       = &sctp_prot,
1021 	.ops        = &inet_seqpacket_ops,
1022 	.no_check   = 0,
1023 	.flags      = SCTP_PROTOSW_FLAG
1024 };
1025 static struct inet_protosw sctp_stream_protosw = {
1026 	.type       = SOCK_STREAM,
1027 	.protocol   = IPPROTO_SCTP,
1028 	.prot       = &sctp_prot,
1029 	.ops        = &inet_seqpacket_ops,
1030 	.no_check   = 0,
1031 	.flags      = SCTP_PROTOSW_FLAG
1032 };
1033 
1034 /* Register with IP layer.  */
1035 static const struct net_protocol sctp_protocol = {
1036 	.handler     = sctp_rcv,
1037 	.err_handler = sctp_v4_err,
1038 	.no_policy   = 1,
1039 	.netns_ok    = 1,
1040 };
1041 
1042 /* IPv4 address related functions.  */
1043 static struct sctp_af sctp_af_inet = {
1044 	.sa_family	   = AF_INET,
1045 	.sctp_xmit	   = sctp_v4_xmit,
1046 	.setsockopt	   = ip_setsockopt,
1047 	.getsockopt	   = ip_getsockopt,
1048 	.get_dst	   = sctp_v4_get_dst,
1049 	.get_saddr	   = sctp_v4_get_saddr,
1050 	.copy_addrlist	   = sctp_v4_copy_addrlist,
1051 	.from_skb	   = sctp_v4_from_skb,
1052 	.from_sk	   = sctp_v4_from_sk,
1053 	.to_sk_saddr	   = sctp_v4_to_sk_saddr,
1054 	.to_sk_daddr	   = sctp_v4_to_sk_daddr,
1055 	.from_addr_param   = sctp_v4_from_addr_param,
1056 	.to_addr_param	   = sctp_v4_to_addr_param,
1057 	.cmp_addr	   = sctp_v4_cmp_addr,
1058 	.addr_valid	   = sctp_v4_addr_valid,
1059 	.inaddr_any	   = sctp_v4_inaddr_any,
1060 	.is_any		   = sctp_v4_is_any,
1061 	.available	   = sctp_v4_available,
1062 	.scope		   = sctp_v4_scope,
1063 	.skb_iif	   = sctp_v4_skb_iif,
1064 	.is_ce		   = sctp_v4_is_ce,
1065 	.seq_dump_addr	   = sctp_v4_seq_dump_addr,
1066 	.ecn_capable	   = sctp_v4_ecn_capable,
1067 	.net_header_len	   = sizeof(struct iphdr),
1068 	.sockaddr_len	   = sizeof(struct sockaddr_in),
1069 #ifdef CONFIG_COMPAT
1070 	.compat_setsockopt = compat_ip_setsockopt,
1071 	.compat_getsockopt = compat_ip_getsockopt,
1072 #endif
1073 };
1074 
1075 struct sctp_pf *sctp_get_pf_specific(sa_family_t family) {
1076 
1077 	switch (family) {
1078 	case PF_INET:
1079 		return sctp_pf_inet_specific;
1080 	case PF_INET6:
1081 		return sctp_pf_inet6_specific;
1082 	default:
1083 		return NULL;
1084 	}
1085 }
1086 
1087 /* Register the PF specific function table.  */
1088 int sctp_register_pf(struct sctp_pf *pf, sa_family_t family)
1089 {
1090 	switch (family) {
1091 	case PF_INET:
1092 		if (sctp_pf_inet_specific)
1093 			return 0;
1094 		sctp_pf_inet_specific = pf;
1095 		break;
1096 	case PF_INET6:
1097 		if (sctp_pf_inet6_specific)
1098 			return 0;
1099 		sctp_pf_inet6_specific = pf;
1100 		break;
1101 	default:
1102 		return 0;
1103 	}
1104 	return 1;
1105 }
1106 
1107 static inline int init_sctp_mibs(struct net *net)
1108 {
1109 	return snmp_mib_init((void __percpu **)net->sctp.sctp_statistics,
1110 			     sizeof(struct sctp_mib),
1111 			     __alignof__(struct sctp_mib));
1112 }
1113 
1114 static inline void cleanup_sctp_mibs(struct net *net)
1115 {
1116 	snmp_mib_free((void __percpu **)net->sctp.sctp_statistics);
1117 }
1118 
1119 static void sctp_v4_pf_init(void)
1120 {
1121 	/* Initialize the SCTP specific PF functions. */
1122 	sctp_register_pf(&sctp_pf_inet, PF_INET);
1123 	sctp_register_af(&sctp_af_inet);
1124 }
1125 
1126 static void sctp_v4_pf_exit(void)
1127 {
1128 	list_del(&sctp_af_inet.list);
1129 }
1130 
1131 static int sctp_v4_protosw_init(void)
1132 {
1133 	int rc;
1134 
1135 	rc = proto_register(&sctp_prot, 1);
1136 	if (rc)
1137 		return rc;
1138 
1139 	/* Register SCTP(UDP and TCP style) with socket layer.  */
1140 	inet_register_protosw(&sctp_seqpacket_protosw);
1141 	inet_register_protosw(&sctp_stream_protosw);
1142 
1143 	return 0;
1144 }
1145 
1146 static void sctp_v4_protosw_exit(void)
1147 {
1148 	inet_unregister_protosw(&sctp_stream_protosw);
1149 	inet_unregister_protosw(&sctp_seqpacket_protosw);
1150 	proto_unregister(&sctp_prot);
1151 }
1152 
1153 static int sctp_v4_add_protocol(void)
1154 {
1155 	/* Register notifier for inet address additions/deletions. */
1156 	register_inetaddr_notifier(&sctp_inetaddr_notifier);
1157 
1158 	/* Register SCTP with inet layer.  */
1159 	if (inet_add_protocol(&sctp_protocol, IPPROTO_SCTP) < 0)
1160 		return -EAGAIN;
1161 
1162 	return 0;
1163 }
1164 
1165 static void sctp_v4_del_protocol(void)
1166 {
1167 	inet_del_protocol(&sctp_protocol, IPPROTO_SCTP);
1168 	unregister_inetaddr_notifier(&sctp_inetaddr_notifier);
1169 }
1170 
1171 static int __net_init sctp_net_init(struct net *net)
1172 {
1173 	int status;
1174 
1175 	/*
1176 	 * 14. Suggested SCTP Protocol Parameter Values
1177 	 */
1178 	/* The following protocol parameters are RECOMMENDED:  */
1179 	/* RTO.Initial              - 3  seconds */
1180 	net->sctp.rto_initial			= SCTP_RTO_INITIAL;
1181 	/* RTO.Min                  - 1  second */
1182 	net->sctp.rto_min	 		= SCTP_RTO_MIN;
1183 	/* RTO.Max                 -  60 seconds */
1184 	net->sctp.rto_max 			= SCTP_RTO_MAX;
1185 	/* RTO.Alpha                - 1/8 */
1186 	net->sctp.rto_alpha			= SCTP_RTO_ALPHA;
1187 	/* RTO.Beta                 - 1/4 */
1188 	net->sctp.rto_beta			= SCTP_RTO_BETA;
1189 
1190 	/* Valid.Cookie.Life        - 60  seconds */
1191 	net->sctp.valid_cookie_life		= SCTP_DEFAULT_COOKIE_LIFE;
1192 
1193 	/* Whether Cookie Preservative is enabled(1) or not(0) */
1194 	net->sctp.cookie_preserve_enable 	= 1;
1195 
1196 	/* Default sctp sockets to use md5 as their hmac alg */
1197 #if defined (CONFIG_SCTP_DEFAULT_COOKIE_HMAC_MD5)
1198 	net->sctp.sctp_hmac_alg			= "md5";
1199 #elif defined (CONFIG_SCTP_DEFAULT_COOKIE_HMAC_SHA1)
1200 	net->sctp.sctp_hmac_alg			= "sha1";
1201 #else
1202 	net->sctp.sctp_hmac_alg			= NULL;
1203 #endif
1204 
1205 	/* Max.Burst		    - 4 */
1206 	net->sctp.max_burst			= SCTP_DEFAULT_MAX_BURST;
1207 
1208 	/* Association.Max.Retrans  - 10 attempts
1209 	 * Path.Max.Retrans         - 5  attempts (per destination address)
1210 	 * Max.Init.Retransmits     - 8  attempts
1211 	 */
1212 	net->sctp.max_retrans_association	= 10;
1213 	net->sctp.max_retrans_path		= 5;
1214 	net->sctp.max_retrans_init		= 8;
1215 
1216 	/* Sendbuffer growth	    - do per-socket accounting */
1217 	net->sctp.sndbuf_policy			= 0;
1218 
1219 	/* Rcvbuffer growth	    - do per-socket accounting */
1220 	net->sctp.rcvbuf_policy			= 0;
1221 
1222 	/* HB.interval              - 30 seconds */
1223 	net->sctp.hb_interval			= SCTP_DEFAULT_TIMEOUT_HEARTBEAT;
1224 
1225 	/* delayed SACK timeout */
1226 	net->sctp.sack_timeout			= SCTP_DEFAULT_TIMEOUT_SACK;
1227 
1228 	/* Disable ADDIP by default. */
1229 	net->sctp.addip_enable = 0;
1230 	net->sctp.addip_noauth = 0;
1231 	net->sctp.default_auto_asconf = 0;
1232 
1233 	/* Enable PR-SCTP by default. */
1234 	net->sctp.prsctp_enable = 1;
1235 
1236 	/* Disable AUTH by default. */
1237 	net->sctp.auth_enable = 0;
1238 
1239 	/* Set SCOPE policy to enabled */
1240 	net->sctp.scope_policy = SCTP_SCOPE_POLICY_ENABLE;
1241 
1242 	/* Set the default rwnd update threshold */
1243 	net->sctp.rwnd_upd_shift = SCTP_DEFAULT_RWND_SHIFT;
1244 
1245 	/* Initialize maximum autoclose timeout. */
1246 	net->sctp.max_autoclose		= INT_MAX / HZ;
1247 
1248 	status = sctp_sysctl_net_register(net);
1249 	if (status)
1250 		goto err_sysctl_register;
1251 
1252 	/* Allocate and initialise sctp mibs.  */
1253 	status = init_sctp_mibs(net);
1254 	if (status)
1255 		goto err_init_mibs;
1256 
1257 	/* Initialize proc fs directory.  */
1258 	status = sctp_proc_init(net);
1259 	if (status)
1260 		goto err_init_proc;
1261 
1262 	sctp_dbg_objcnt_init(net);
1263 
1264 	/* Initialize the control inode/socket for handling OOTB packets.  */
1265 	if ((status = sctp_ctl_sock_init(net))) {
1266 		pr_err("Failed to initialize the SCTP control sock\n");
1267 		goto err_ctl_sock_init;
1268 	}
1269 
1270 	/* Initialize the local address list. */
1271 	INIT_LIST_HEAD(&net->sctp.local_addr_list);
1272 	spin_lock_init(&net->sctp.local_addr_lock);
1273 	sctp_get_local_addr_list(net);
1274 
1275 	/* Initialize the address event list */
1276 	INIT_LIST_HEAD(&net->sctp.addr_waitq);
1277 	INIT_LIST_HEAD(&net->sctp.auto_asconf_splist);
1278 	spin_lock_init(&net->sctp.addr_wq_lock);
1279 	net->sctp.addr_wq_timer.expires = 0;
1280 	setup_timer(&net->sctp.addr_wq_timer, sctp_addr_wq_timeout_handler,
1281 		    (unsigned long)net);
1282 
1283 	return 0;
1284 
1285 err_ctl_sock_init:
1286 	sctp_dbg_objcnt_exit(net);
1287 	sctp_proc_exit(net);
1288 err_init_proc:
1289 	cleanup_sctp_mibs(net);
1290 err_init_mibs:
1291 	sctp_sysctl_net_unregister(net);
1292 err_sysctl_register:
1293 	return status;
1294 }
1295 
1296 static void __net_exit sctp_net_exit(struct net *net)
1297 {
1298 	/* Free the local address list */
1299 	sctp_free_addr_wq(net);
1300 	sctp_free_local_addr_list(net);
1301 
1302 	/* Free the control endpoint.  */
1303 	inet_ctl_sock_destroy(net->sctp.ctl_sock);
1304 
1305 	sctp_dbg_objcnt_exit(net);
1306 
1307 	sctp_proc_exit(net);
1308 	cleanup_sctp_mibs(net);
1309 	sctp_sysctl_net_unregister(net);
1310 }
1311 
1312 static struct pernet_operations sctp_net_ops = {
1313 	.init = sctp_net_init,
1314 	.exit = sctp_net_exit,
1315 };
1316 
1317 /* Initialize the universe into something sensible.  */
1318 static __init int sctp_init(void)
1319 {
1320 	int i;
1321 	int status = -EINVAL;
1322 	unsigned long goal;
1323 	unsigned long limit;
1324 	int max_share;
1325 	int order;
1326 
1327 	BUILD_BUG_ON(sizeof(struct sctp_ulpevent) >
1328 		     sizeof(((struct sk_buff *) 0)->cb));
1329 
1330 	/* Allocate bind_bucket and chunk caches. */
1331 	status = -ENOBUFS;
1332 	sctp_bucket_cachep = kmem_cache_create("sctp_bind_bucket",
1333 					       sizeof(struct sctp_bind_bucket),
1334 					       0, SLAB_HWCACHE_ALIGN,
1335 					       NULL);
1336 	if (!sctp_bucket_cachep)
1337 		goto out;
1338 
1339 	sctp_chunk_cachep = kmem_cache_create("sctp_chunk",
1340 					       sizeof(struct sctp_chunk),
1341 					       0, SLAB_HWCACHE_ALIGN,
1342 					       NULL);
1343 	if (!sctp_chunk_cachep)
1344 		goto err_chunk_cachep;
1345 
1346 	status = percpu_counter_init(&sctp_sockets_allocated, 0);
1347 	if (status)
1348 		goto err_percpu_counter_init;
1349 
1350 	/* Implementation specific variables. */
1351 
1352 	/* Initialize default stream count setup information. */
1353 	sctp_max_instreams    		= SCTP_DEFAULT_INSTREAMS;
1354 	sctp_max_outstreams   		= SCTP_DEFAULT_OUTSTREAMS;
1355 
1356 	/* Initialize handle used for association ids. */
1357 	idr_init(&sctp_assocs_id);
1358 
1359 	limit = nr_free_buffer_pages() / 8;
1360 	limit = max(limit, 128UL);
1361 	sysctl_sctp_mem[0] = limit / 4 * 3;
1362 	sysctl_sctp_mem[1] = limit;
1363 	sysctl_sctp_mem[2] = sysctl_sctp_mem[0] * 2;
1364 
1365 	/* Set per-socket limits to no more than 1/128 the pressure threshold*/
1366 	limit = (sysctl_sctp_mem[1]) << (PAGE_SHIFT - 7);
1367 	max_share = min(4UL*1024*1024, limit);
1368 
1369 	sysctl_sctp_rmem[0] = SK_MEM_QUANTUM; /* give each asoc 1 page min */
1370 	sysctl_sctp_rmem[1] = 1500 * SKB_TRUESIZE(1);
1371 	sysctl_sctp_rmem[2] = max(sysctl_sctp_rmem[1], max_share);
1372 
1373 	sysctl_sctp_wmem[0] = SK_MEM_QUANTUM;
1374 	sysctl_sctp_wmem[1] = 16*1024;
1375 	sysctl_sctp_wmem[2] = max(64*1024, max_share);
1376 
1377 	/* Size and allocate the association hash table.
1378 	 * The methodology is similar to that of the tcp hash tables.
1379 	 */
1380 	if (totalram_pages >= (128 * 1024))
1381 		goal = totalram_pages >> (22 - PAGE_SHIFT);
1382 	else
1383 		goal = totalram_pages >> (24 - PAGE_SHIFT);
1384 
1385 	for (order = 0; (1UL << order) < goal; order++)
1386 		;
1387 
1388 	do {
1389 		sctp_assoc_hashsize = (1UL << order) * PAGE_SIZE /
1390 					sizeof(struct sctp_hashbucket);
1391 		if ((sctp_assoc_hashsize > (64 * 1024)) && order > 0)
1392 			continue;
1393 		sctp_assoc_hashtable = (struct sctp_hashbucket *)
1394 			__get_free_pages(GFP_ATOMIC|__GFP_NOWARN, order);
1395 	} while (!sctp_assoc_hashtable && --order > 0);
1396 	if (!sctp_assoc_hashtable) {
1397 		pr_err("Failed association hash alloc\n");
1398 		status = -ENOMEM;
1399 		goto err_ahash_alloc;
1400 	}
1401 	for (i = 0; i < sctp_assoc_hashsize; i++) {
1402 		rwlock_init(&sctp_assoc_hashtable[i].lock);
1403 		INIT_HLIST_HEAD(&sctp_assoc_hashtable[i].chain);
1404 	}
1405 
1406 	/* Allocate and initialize the endpoint hash table.  */
1407 	sctp_ep_hashsize = 64;
1408 	sctp_ep_hashtable =
1409 		kmalloc(64 * sizeof(struct sctp_hashbucket), GFP_KERNEL);
1410 	if (!sctp_ep_hashtable) {
1411 		pr_err("Failed endpoint_hash alloc\n");
1412 		status = -ENOMEM;
1413 		goto err_ehash_alloc;
1414 	}
1415 	for (i = 0; i < sctp_ep_hashsize; i++) {
1416 		rwlock_init(&sctp_ep_hashtable[i].lock);
1417 		INIT_HLIST_HEAD(&sctp_ep_hashtable[i].chain);
1418 	}
1419 
1420 	/* Allocate and initialize the SCTP port hash table.  */
1421 	do {
1422 		sctp_port_hashsize = (1UL << order) * PAGE_SIZE /
1423 					sizeof(struct sctp_bind_hashbucket);
1424 		if ((sctp_port_hashsize > (64 * 1024)) && order > 0)
1425 			continue;
1426 		sctp_port_hashtable = (struct sctp_bind_hashbucket *)
1427 			__get_free_pages(GFP_ATOMIC|__GFP_NOWARN, order);
1428 	} while (!sctp_port_hashtable && --order > 0);
1429 	if (!sctp_port_hashtable) {
1430 		pr_err("Failed bind hash alloc\n");
1431 		status = -ENOMEM;
1432 		goto err_bhash_alloc;
1433 	}
1434 	for (i = 0; i < sctp_port_hashsize; i++) {
1435 		spin_lock_init(&sctp_port_hashtable[i].lock);
1436 		INIT_HLIST_HEAD(&sctp_port_hashtable[i].chain);
1437 	}
1438 
1439 	pr_info("Hash tables configured (established %d bind %d)\n",
1440 		sctp_assoc_hashsize, sctp_port_hashsize);
1441 
1442 	sctp_sysctl_register();
1443 
1444 	INIT_LIST_HEAD(&sctp_address_families);
1445 	sctp_v4_pf_init();
1446 	sctp_v6_pf_init();
1447 
1448 	status = sctp_v4_protosw_init();
1449 
1450 	if (status)
1451 		goto err_protosw_init;
1452 
1453 	status = sctp_v6_protosw_init();
1454 	if (status)
1455 		goto err_v6_protosw_init;
1456 
1457 	status = register_pernet_subsys(&sctp_net_ops);
1458 	if (status)
1459 		goto err_register_pernet_subsys;
1460 
1461 	status = sctp_v4_add_protocol();
1462 	if (status)
1463 		goto err_add_protocol;
1464 
1465 	/* Register SCTP with inet6 layer.  */
1466 	status = sctp_v6_add_protocol();
1467 	if (status)
1468 		goto err_v6_add_protocol;
1469 
1470 	status = 0;
1471 out:
1472 	return status;
1473 err_v6_add_protocol:
1474 	sctp_v4_del_protocol();
1475 err_add_protocol:
1476 	unregister_pernet_subsys(&sctp_net_ops);
1477 err_register_pernet_subsys:
1478 	sctp_v6_protosw_exit();
1479 err_v6_protosw_init:
1480 	sctp_v4_protosw_exit();
1481 err_protosw_init:
1482 	sctp_v4_pf_exit();
1483 	sctp_v6_pf_exit();
1484 	sctp_sysctl_unregister();
1485 	free_pages((unsigned long)sctp_port_hashtable,
1486 		   get_order(sctp_port_hashsize *
1487 			     sizeof(struct sctp_bind_hashbucket)));
1488 err_bhash_alloc:
1489 	kfree(sctp_ep_hashtable);
1490 err_ehash_alloc:
1491 	free_pages((unsigned long)sctp_assoc_hashtable,
1492 		   get_order(sctp_assoc_hashsize *
1493 			     sizeof(struct sctp_hashbucket)));
1494 err_ahash_alloc:
1495 	percpu_counter_destroy(&sctp_sockets_allocated);
1496 err_percpu_counter_init:
1497 	kmem_cache_destroy(sctp_chunk_cachep);
1498 err_chunk_cachep:
1499 	kmem_cache_destroy(sctp_bucket_cachep);
1500 	goto out;
1501 }
1502 
1503 /* Exit handler for the SCTP protocol.  */
1504 static __exit void sctp_exit(void)
1505 {
1506 	/* BUG.  This should probably do something useful like clean
1507 	 * up all the remaining associations and all that memory.
1508 	 */
1509 
1510 	/* Unregister with inet6/inet layers. */
1511 	sctp_v6_del_protocol();
1512 	sctp_v4_del_protocol();
1513 
1514 	unregister_pernet_subsys(&sctp_net_ops);
1515 
1516 	/* Free protosw registrations */
1517 	sctp_v6_protosw_exit();
1518 	sctp_v4_protosw_exit();
1519 
1520 	/* Unregister with socket layer. */
1521 	sctp_v6_pf_exit();
1522 	sctp_v4_pf_exit();
1523 
1524 	sctp_sysctl_unregister();
1525 
1526 	free_pages((unsigned long)sctp_assoc_hashtable,
1527 		   get_order(sctp_assoc_hashsize *
1528 			     sizeof(struct sctp_hashbucket)));
1529 	kfree(sctp_ep_hashtable);
1530 	free_pages((unsigned long)sctp_port_hashtable,
1531 		   get_order(sctp_port_hashsize *
1532 			     sizeof(struct sctp_bind_hashbucket)));
1533 
1534 	percpu_counter_destroy(&sctp_sockets_allocated);
1535 
1536 	rcu_barrier(); /* Wait for completion of call_rcu()'s */
1537 
1538 	kmem_cache_destroy(sctp_chunk_cachep);
1539 	kmem_cache_destroy(sctp_bucket_cachep);
1540 }
1541 
1542 module_init(sctp_init);
1543 module_exit(sctp_exit);
1544 
1545 /*
1546  * __stringify doesn't likes enums, so use IPPROTO_SCTP value (132) directly.
1547  */
1548 MODULE_ALIAS("net-pf-" __stringify(PF_INET) "-proto-132");
1549 MODULE_ALIAS("net-pf-" __stringify(PF_INET6) "-proto-132");
1550 MODULE_AUTHOR("Linux Kernel SCTP developers <lksctp-developers@lists.sourceforge.net>");
1551 MODULE_DESCRIPTION("Support for the SCTP protocol (RFC2960)");
1552 module_param_named(no_checksums, sctp_checksum_disable, bool, 0644);
1553 MODULE_PARM_DESC(no_checksums, "Disable checksums computing and verification");
1554 MODULE_LICENSE("GPL");
1555