xref: /linux/net/sctp/protocol.c (revision ac6a0cf6716bb46813d0161024c66c2af66e53d1)
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 #include <linux/module.h>
50 #include <linux/init.h>
51 #include <linux/netdevice.h>
52 #include <linux/inetdevice.h>
53 #include <linux/seq_file.h>
54 #include <linux/bootmem.h>
55 #include <linux/highmem.h>
56 #include <linux/swap.h>
57 #include <net/net_namespace.h>
58 #include <net/protocol.h>
59 #include <net/ip.h>
60 #include <net/ipv6.h>
61 #include <net/route.h>
62 #include <net/sctp/sctp.h>
63 #include <net/addrconf.h>
64 #include <net/inet_common.h>
65 #include <net/inet_ecn.h>
66 
67 /* Global data structures. */
68 struct sctp_globals sctp_globals __read_mostly;
69 DEFINE_SNMP_STAT(struct sctp_mib, sctp_statistics) __read_mostly;
70 
71 #ifdef CONFIG_PROC_FS
72 struct proc_dir_entry	*proc_net_sctp;
73 #endif
74 
75 struct idr sctp_assocs_id;
76 DEFINE_SPINLOCK(sctp_assocs_id_lock);
77 
78 /* This is the global socket data structure used for responding to
79  * the Out-of-the-blue (OOTB) packets.  A control sock will be created
80  * for this socket at the initialization time.
81  */
82 static struct sock *sctp_ctl_sock;
83 
84 static struct sctp_pf *sctp_pf_inet6_specific;
85 static struct sctp_pf *sctp_pf_inet_specific;
86 static struct sctp_af *sctp_af_v4_specific;
87 static struct sctp_af *sctp_af_v6_specific;
88 
89 struct kmem_cache *sctp_chunk_cachep __read_mostly;
90 struct kmem_cache *sctp_bucket_cachep __read_mostly;
91 
92 int sysctl_sctp_mem[3];
93 int sysctl_sctp_rmem[3];
94 int sysctl_sctp_wmem[3];
95 
96 /* Return the address of the control sock. */
97 struct sock *sctp_get_ctl_sock(void)
98 {
99 	return sctp_ctl_sock;
100 }
101 
102 /* Set up the proc fs entry for the SCTP protocol. */
103 static __init int sctp_proc_init(void)
104 {
105 	if (percpu_counter_init(&sctp_sockets_allocated, 0))
106 		goto out_nomem;
107 #ifdef CONFIG_PROC_FS
108 	if (!proc_net_sctp) {
109 		proc_net_sctp = proc_mkdir("sctp", init_net.proc_net);
110 		if (!proc_net_sctp)
111 			goto out_free_percpu;
112 	}
113 
114 	if (sctp_snmp_proc_init())
115 		goto out_snmp_proc_init;
116 	if (sctp_eps_proc_init())
117 		goto out_eps_proc_init;
118 	if (sctp_assocs_proc_init())
119 		goto out_assocs_proc_init;
120 	if (sctp_remaddr_proc_init())
121 		goto out_remaddr_proc_init;
122 
123 	return 0;
124 
125 out_remaddr_proc_init:
126 	sctp_assocs_proc_exit();
127 out_assocs_proc_init:
128 	sctp_eps_proc_exit();
129 out_eps_proc_init:
130 	sctp_snmp_proc_exit();
131 out_snmp_proc_init:
132 	if (proc_net_sctp) {
133 		proc_net_sctp = NULL;
134 		remove_proc_entry("sctp", init_net.proc_net);
135 	}
136 out_free_percpu:
137 	percpu_counter_destroy(&sctp_sockets_allocated);
138 #else
139 	return 0;
140 #endif /* CONFIG_PROC_FS */
141 
142 out_nomem:
143 	return -ENOMEM;
144 }
145 
146 /* Clean up the proc fs entry for the SCTP protocol.
147  * Note: Do not make this __exit as it is used in the init error
148  * path.
149  */
150 static void sctp_proc_exit(void)
151 {
152 #ifdef CONFIG_PROC_FS
153 	sctp_snmp_proc_exit();
154 	sctp_eps_proc_exit();
155 	sctp_assocs_proc_exit();
156 	sctp_remaddr_proc_exit();
157 
158 	if (proc_net_sctp) {
159 		proc_net_sctp = NULL;
160 		remove_proc_entry("sctp", init_net.proc_net);
161 	}
162 #endif
163 	percpu_counter_destroy(&sctp_sockets_allocated);
164 }
165 
166 /* Private helper to extract ipv4 address and stash them in
167  * the protocol structure.
168  */
169 static void sctp_v4_copy_addrlist(struct list_head *addrlist,
170 				  struct net_device *dev)
171 {
172 	struct in_device *in_dev;
173 	struct in_ifaddr *ifa;
174 	struct sctp_sockaddr_entry *addr;
175 
176 	rcu_read_lock();
177 	if ((in_dev = __in_dev_get_rcu(dev)) == NULL) {
178 		rcu_read_unlock();
179 		return;
180 	}
181 
182 	for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
183 		/* Add the address to the local list.  */
184 		addr = t_new(struct sctp_sockaddr_entry, GFP_ATOMIC);
185 		if (addr) {
186 			addr->a.v4.sin_family = AF_INET;
187 			addr->a.v4.sin_port = 0;
188 			addr->a.v4.sin_addr.s_addr = ifa->ifa_local;
189 			addr->valid = 1;
190 			INIT_LIST_HEAD(&addr->list);
191 			INIT_RCU_HEAD(&addr->rcu);
192 			list_add_tail(&addr->list, addrlist);
193 		}
194 	}
195 
196 	rcu_read_unlock();
197 }
198 
199 /* Extract our IP addresses from the system and stash them in the
200  * protocol structure.
201  */
202 static void sctp_get_local_addr_list(void)
203 {
204 	struct net_device *dev;
205 	struct list_head *pos;
206 	struct sctp_af *af;
207 
208 	read_lock(&dev_base_lock);
209 	for_each_netdev(&init_net, dev) {
210 		__list_for_each(pos, &sctp_address_families) {
211 			af = list_entry(pos, struct sctp_af, list);
212 			af->copy_addrlist(&sctp_local_addr_list, dev);
213 		}
214 	}
215 	read_unlock(&dev_base_lock);
216 }
217 
218 /* Free the existing local addresses.  */
219 static void sctp_free_local_addr_list(void)
220 {
221 	struct sctp_sockaddr_entry *addr;
222 	struct list_head *pos, *temp;
223 
224 	list_for_each_safe(pos, temp, &sctp_local_addr_list) {
225 		addr = list_entry(pos, struct sctp_sockaddr_entry, list);
226 		list_del(pos);
227 		kfree(addr);
228 	}
229 }
230 
231 void sctp_local_addr_free(struct rcu_head *head)
232 {
233 	struct sctp_sockaddr_entry *e = container_of(head,
234 				struct sctp_sockaddr_entry, rcu);
235 	kfree(e);
236 }
237 
238 /* Copy the local addresses which are valid for 'scope' into 'bp'.  */
239 int sctp_copy_local_addr_list(struct sctp_bind_addr *bp, sctp_scope_t scope,
240 			      gfp_t gfp, int copy_flags)
241 {
242 	struct sctp_sockaddr_entry *addr;
243 	int error = 0;
244 
245 	rcu_read_lock();
246 	list_for_each_entry_rcu(addr, &sctp_local_addr_list, list) {
247 		if (!addr->valid)
248 			continue;
249 		if (sctp_in_scope(&addr->a, scope)) {
250 			/* Now that the address is in scope, check to see if
251 			 * the address type is really supported by the local
252 			 * sock as well as the remote peer.
253 			 */
254 			if ((((AF_INET == addr->a.sa.sa_family) &&
255 			      (copy_flags & SCTP_ADDR4_PEERSUPP))) ||
256 			    (((AF_INET6 == addr->a.sa.sa_family) &&
257 			      (copy_flags & SCTP_ADDR6_ALLOWED) &&
258 			      (copy_flags & SCTP_ADDR6_PEERSUPP)))) {
259 				error = sctp_add_bind_addr(bp, &addr->a,
260 						    SCTP_ADDR_SRC, GFP_ATOMIC);
261 				if (error)
262 					goto end_copy;
263 			}
264 		}
265 	}
266 
267 end_copy:
268 	rcu_read_unlock();
269 	return error;
270 }
271 
272 /* Initialize a sctp_addr from in incoming skb.  */
273 static void sctp_v4_from_skb(union sctp_addr *addr, struct sk_buff *skb,
274 			     int is_saddr)
275 {
276 	void *from;
277 	__be16 *port;
278 	struct sctphdr *sh;
279 
280 	port = &addr->v4.sin_port;
281 	addr->v4.sin_family = AF_INET;
282 
283 	sh = sctp_hdr(skb);
284 	if (is_saddr) {
285 		*port  = sh->source;
286 		from = &ip_hdr(skb)->saddr;
287 	} else {
288 		*port = sh->dest;
289 		from = &ip_hdr(skb)->daddr;
290 	}
291 	memcpy(&addr->v4.sin_addr.s_addr, from, sizeof(struct in_addr));
292 }
293 
294 /* Initialize an sctp_addr from a socket. */
295 static void sctp_v4_from_sk(union sctp_addr *addr, struct sock *sk)
296 {
297 	addr->v4.sin_family = AF_INET;
298 	addr->v4.sin_port = 0;
299 	addr->v4.sin_addr.s_addr = inet_sk(sk)->rcv_saddr;
300 }
301 
302 /* Initialize sk->sk_rcv_saddr from sctp_addr. */
303 static void sctp_v4_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
304 {
305 	inet_sk(sk)->rcv_saddr = addr->v4.sin_addr.s_addr;
306 }
307 
308 /* Initialize sk->sk_daddr from sctp_addr. */
309 static void sctp_v4_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
310 {
311 	inet_sk(sk)->daddr = addr->v4.sin_addr.s_addr;
312 }
313 
314 /* Initialize a sctp_addr from an address parameter. */
315 static void sctp_v4_from_addr_param(union sctp_addr *addr,
316 				    union sctp_addr_param *param,
317 				    __be16 port, int iif)
318 {
319 	addr->v4.sin_family = AF_INET;
320 	addr->v4.sin_port = port;
321 	addr->v4.sin_addr.s_addr = param->v4.addr.s_addr;
322 }
323 
324 /* Initialize an address parameter from a sctp_addr and return the length
325  * of the address parameter.
326  */
327 static int sctp_v4_to_addr_param(const union sctp_addr *addr,
328 				 union sctp_addr_param *param)
329 {
330 	int length = sizeof(sctp_ipv4addr_param_t);
331 
332 	param->v4.param_hdr.type = SCTP_PARAM_IPV4_ADDRESS;
333 	param->v4.param_hdr.length = htons(length);
334 	param->v4.addr.s_addr = addr->v4.sin_addr.s_addr;
335 
336 	return length;
337 }
338 
339 /* Initialize a sctp_addr from a dst_entry. */
340 static void sctp_v4_dst_saddr(union sctp_addr *saddr, struct dst_entry *dst,
341 			      __be16 port)
342 {
343 	struct rtable *rt = (struct rtable *)dst;
344 	saddr->v4.sin_family = AF_INET;
345 	saddr->v4.sin_port = port;
346 	saddr->v4.sin_addr.s_addr = rt->rt_src;
347 }
348 
349 /* Compare two addresses exactly. */
350 static int sctp_v4_cmp_addr(const union sctp_addr *addr1,
351 			    const union sctp_addr *addr2)
352 {
353 	if (addr1->sa.sa_family != addr2->sa.sa_family)
354 		return 0;
355 	if (addr1->v4.sin_port != addr2->v4.sin_port)
356 		return 0;
357 	if (addr1->v4.sin_addr.s_addr != addr2->v4.sin_addr.s_addr)
358 		return 0;
359 
360 	return 1;
361 }
362 
363 /* Initialize addr struct to INADDR_ANY. */
364 static void sctp_v4_inaddr_any(union sctp_addr *addr, __be16 port)
365 {
366 	addr->v4.sin_family = AF_INET;
367 	addr->v4.sin_addr.s_addr = htonl(INADDR_ANY);
368 	addr->v4.sin_port = port;
369 }
370 
371 /* Is this a wildcard address? */
372 static int sctp_v4_is_any(const union sctp_addr *addr)
373 {
374 	return htonl(INADDR_ANY) == addr->v4.sin_addr.s_addr;
375 }
376 
377 /* This function checks if the address is a valid address to be used for
378  * SCTP binding.
379  *
380  * Output:
381  * Return 0 - If the address is a non-unicast or an illegal address.
382  * Return 1 - If the address is a unicast.
383  */
384 static int sctp_v4_addr_valid(union sctp_addr *addr,
385 			      struct sctp_sock *sp,
386 			      const struct sk_buff *skb)
387 {
388 	/* IPv4 addresses not allowed */
389 	if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
390 		return 0;
391 
392 	/* Is this a non-unicast address or a unusable SCTP address? */
393 	if (IS_IPV4_UNUSABLE_ADDRESS(addr->v4.sin_addr.s_addr))
394 		return 0;
395 
396 	/* Is this a broadcast address? */
397 	if (skb && skb_rtable(skb)->rt_flags & RTCF_BROADCAST)
398 		return 0;
399 
400 	return 1;
401 }
402 
403 /* Should this be available for binding?   */
404 static int sctp_v4_available(union sctp_addr *addr, struct sctp_sock *sp)
405 {
406 	int ret = inet_addr_type(&init_net, addr->v4.sin_addr.s_addr);
407 
408 
409 	if (addr->v4.sin_addr.s_addr != htonl(INADDR_ANY) &&
410 	   ret != RTN_LOCAL &&
411 	   !sp->inet.freebind &&
412 	   !sysctl_ip_nonlocal_bind)
413 		return 0;
414 
415 	if (ipv6_only_sock(sctp_opt2sk(sp)))
416 		return 0;
417 
418 	return 1;
419 }
420 
421 /* Checking the loopback, private and other address scopes as defined in
422  * RFC 1918.   The IPv4 scoping is based on the draft for SCTP IPv4
423  * scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>.
424  *
425  * Level 0 - unusable SCTP addresses
426  * Level 1 - loopback address
427  * Level 2 - link-local addresses
428  * Level 3 - private addresses.
429  * Level 4 - global addresses
430  * For INIT and INIT-ACK address list, let L be the level of
431  * of requested destination address, sender and receiver
432  * SHOULD include all of its addresses with level greater
433  * than or equal to L.
434  */
435 static sctp_scope_t sctp_v4_scope(union sctp_addr *addr)
436 {
437 	sctp_scope_t retval;
438 
439 	/* Should IPv4 scoping be a sysctl configurable option
440 	 * so users can turn it off (default on) for certain
441 	 * unconventional networking environments?
442 	 */
443 
444 	/* Check for unusable SCTP addresses. */
445 	if (IS_IPV4_UNUSABLE_ADDRESS(addr->v4.sin_addr.s_addr)) {
446 		retval =  SCTP_SCOPE_UNUSABLE;
447 	} else if (ipv4_is_loopback(addr->v4.sin_addr.s_addr)) {
448 		retval = SCTP_SCOPE_LOOPBACK;
449 	} else if (ipv4_is_linklocal_169(addr->v4.sin_addr.s_addr)) {
450 		retval = SCTP_SCOPE_LINK;
451 	} else if (ipv4_is_private_10(addr->v4.sin_addr.s_addr) ||
452 		   ipv4_is_private_172(addr->v4.sin_addr.s_addr) ||
453 		   ipv4_is_private_192(addr->v4.sin_addr.s_addr)) {
454 		retval = SCTP_SCOPE_PRIVATE;
455 	} else {
456 		retval = SCTP_SCOPE_GLOBAL;
457 	}
458 
459 	return retval;
460 }
461 
462 /* Returns a valid dst cache entry for the given source and destination ip
463  * addresses. If an association is passed, trys to get a dst entry with a
464  * source address that matches an address in the bind address list.
465  */
466 static struct dst_entry *sctp_v4_get_dst(struct sctp_association *asoc,
467 					 union sctp_addr *daddr,
468 					 union sctp_addr *saddr)
469 {
470 	struct rtable *rt;
471 	struct flowi fl;
472 	struct sctp_bind_addr *bp;
473 	struct sctp_sockaddr_entry *laddr;
474 	struct dst_entry *dst = NULL;
475 	union sctp_addr dst_saddr;
476 
477 	memset(&fl, 0x0, sizeof(struct flowi));
478 	fl.fl4_dst  = daddr->v4.sin_addr.s_addr;
479 	fl.proto = IPPROTO_SCTP;
480 	if (asoc) {
481 		fl.fl4_tos = RT_CONN_FLAGS(asoc->base.sk);
482 		fl.oif = asoc->base.sk->sk_bound_dev_if;
483 	}
484 	if (saddr)
485 		fl.fl4_src = saddr->v4.sin_addr.s_addr;
486 
487 	SCTP_DEBUG_PRINTK("%s: DST:%pI4, SRC:%pI4 - ",
488 			  __func__, &fl.fl4_dst, &fl.fl4_src);
489 
490 	if (!ip_route_output_key(&init_net, &rt, &fl)) {
491 		dst = &rt->u.dst;
492 	}
493 
494 	/* If there is no association or if a source address is passed, no
495 	 * more validation is required.
496 	 */
497 	if (!asoc || saddr)
498 		goto out;
499 
500 	bp = &asoc->base.bind_addr;
501 
502 	if (dst) {
503 		/* Walk through the bind address list and look for a bind
504 		 * address that matches the source address of the returned dst.
505 		 */
506 		sctp_v4_dst_saddr(&dst_saddr, dst, htons(bp->port));
507 		rcu_read_lock();
508 		list_for_each_entry_rcu(laddr, &bp->address_list, list) {
509 			if (!laddr->valid || (laddr->state != SCTP_ADDR_SRC))
510 				continue;
511 			if (sctp_v4_cmp_addr(&dst_saddr, &laddr->a))
512 				goto out_unlock;
513 		}
514 		rcu_read_unlock();
515 
516 		/* None of the bound addresses match the source address of the
517 		 * dst. So release it.
518 		 */
519 		dst_release(dst);
520 		dst = NULL;
521 	}
522 
523 	/* Walk through the bind address list and try to get a dst that
524 	 * matches a bind address as the source address.
525 	 */
526 	rcu_read_lock();
527 	list_for_each_entry_rcu(laddr, &bp->address_list, list) {
528 		if (!laddr->valid)
529 			continue;
530 		if ((laddr->state == SCTP_ADDR_SRC) &&
531 		    (AF_INET == laddr->a.sa.sa_family)) {
532 			fl.fl4_src = laddr->a.v4.sin_addr.s_addr;
533 			if (!ip_route_output_key(&init_net, &rt, &fl)) {
534 				dst = &rt->u.dst;
535 				goto out_unlock;
536 			}
537 		}
538 	}
539 
540 out_unlock:
541 	rcu_read_unlock();
542 out:
543 	if (dst)
544 		SCTP_DEBUG_PRINTK("rt_dst:%pI4, rt_src:%pI4\n",
545 				  &rt->rt_dst, &rt->rt_src);
546 	else
547 		SCTP_DEBUG_PRINTK("NO ROUTE\n");
548 
549 	return dst;
550 }
551 
552 /* For v4, the source address is cached in the route entry(dst). So no need
553  * to cache it separately and hence this is an empty routine.
554  */
555 static void sctp_v4_get_saddr(struct sctp_sock *sk,
556 			      struct sctp_association *asoc,
557 			      struct dst_entry *dst,
558 			      union sctp_addr *daddr,
559 			      union sctp_addr *saddr)
560 {
561 	struct rtable *rt = (struct rtable *)dst;
562 
563 	if (!asoc)
564 		return;
565 
566 	if (rt) {
567 		saddr->v4.sin_family = AF_INET;
568 		saddr->v4.sin_port = htons(asoc->base.bind_addr.port);
569 		saddr->v4.sin_addr.s_addr = rt->rt_src;
570 	}
571 }
572 
573 /* What interface did this skb arrive on? */
574 static int sctp_v4_skb_iif(const struct sk_buff *skb)
575 {
576 	return skb_rtable(skb)->rt_iif;
577 }
578 
579 /* Was this packet marked by Explicit Congestion Notification? */
580 static int sctp_v4_is_ce(const struct sk_buff *skb)
581 {
582 	return INET_ECN_is_ce(ip_hdr(skb)->tos);
583 }
584 
585 /* Create and initialize a new sk for the socket returned by accept(). */
586 static struct sock *sctp_v4_create_accept_sk(struct sock *sk,
587 					     struct sctp_association *asoc)
588 {
589 	struct sock *newsk = sk_alloc(sock_net(sk), PF_INET, GFP_KERNEL,
590 			sk->sk_prot);
591 	struct inet_sock *newinet;
592 
593 	if (!newsk)
594 		goto out;
595 
596 	sock_init_data(NULL, newsk);
597 
598 	sctp_copy_sock(newsk, sk, asoc);
599 	sock_reset_flag(newsk, SOCK_ZAPPED);
600 
601 	newinet = inet_sk(newsk);
602 
603 	newinet->daddr = asoc->peer.primary_addr.v4.sin_addr.s_addr;
604 
605 	sk_refcnt_debug_inc(newsk);
606 
607 	if (newsk->sk_prot->init(newsk)) {
608 		sk_common_release(newsk);
609 		newsk = NULL;
610 	}
611 
612 out:
613 	return newsk;
614 }
615 
616 /* Map address, empty for v4 family */
617 static void sctp_v4_addr_v4map(struct sctp_sock *sp, union sctp_addr *addr)
618 {
619 	/* Empty */
620 }
621 
622 /* Dump the v4 addr to the seq file. */
623 static void sctp_v4_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
624 {
625 	seq_printf(seq, "%pI4 ", &addr->v4.sin_addr);
626 }
627 
628 static void sctp_v4_ecn_capable(struct sock *sk)
629 {
630 	INET_ECN_xmit(sk);
631 }
632 
633 /* Event handler for inet address addition/deletion events.
634  * The sctp_local_addr_list needs to be protocted by a spin lock since
635  * multiple notifiers (say IPv4 and IPv6) may be running at the same
636  * time and thus corrupt the list.
637  * The reader side is protected with RCU.
638  */
639 static int sctp_inetaddr_event(struct notifier_block *this, unsigned long ev,
640 			       void *ptr)
641 {
642 	struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
643 	struct sctp_sockaddr_entry *addr = NULL;
644 	struct sctp_sockaddr_entry *temp;
645 	int found = 0;
646 
647 	if (!net_eq(dev_net(ifa->ifa_dev->dev), &init_net))
648 		return NOTIFY_DONE;
649 
650 	switch (ev) {
651 	case NETDEV_UP:
652 		addr = kmalloc(sizeof(struct sctp_sockaddr_entry), GFP_ATOMIC);
653 		if (addr) {
654 			addr->a.v4.sin_family = AF_INET;
655 			addr->a.v4.sin_port = 0;
656 			addr->a.v4.sin_addr.s_addr = ifa->ifa_local;
657 			addr->valid = 1;
658 			spin_lock_bh(&sctp_local_addr_lock);
659 			list_add_tail_rcu(&addr->list, &sctp_local_addr_list);
660 			spin_unlock_bh(&sctp_local_addr_lock);
661 		}
662 		break;
663 	case NETDEV_DOWN:
664 		spin_lock_bh(&sctp_local_addr_lock);
665 		list_for_each_entry_safe(addr, temp,
666 					&sctp_local_addr_list, list) {
667 			if (addr->a.sa.sa_family == AF_INET &&
668 					addr->a.v4.sin_addr.s_addr ==
669 					ifa->ifa_local) {
670 				found = 1;
671 				addr->valid = 0;
672 				list_del_rcu(&addr->list);
673 				break;
674 			}
675 		}
676 		spin_unlock_bh(&sctp_local_addr_lock);
677 		if (found)
678 			call_rcu(&addr->rcu, sctp_local_addr_free);
679 		break;
680 	}
681 
682 	return NOTIFY_DONE;
683 }
684 
685 /*
686  * Initialize the control inode/socket with a control endpoint data
687  * structure.  This endpoint is reserved exclusively for the OOTB processing.
688  */
689 static int sctp_ctl_sock_init(void)
690 {
691 	int err;
692 	sa_family_t family = PF_INET;
693 
694 	if (sctp_get_pf_specific(PF_INET6))
695 		family = PF_INET6;
696 
697 	err = inet_ctl_sock_create(&sctp_ctl_sock, family,
698 				   SOCK_SEQPACKET, IPPROTO_SCTP, &init_net);
699 
700 	/* If IPv6 socket could not be created, try the IPv4 socket */
701 	if (err < 0 && family == PF_INET6)
702 		err = inet_ctl_sock_create(&sctp_ctl_sock, AF_INET,
703 					   SOCK_SEQPACKET, IPPROTO_SCTP,
704 					   &init_net);
705 
706 	if (err < 0) {
707 		printk(KERN_ERR
708 		       "SCTP: Failed to create the SCTP control socket.\n");
709 		return err;
710 	}
711 	return 0;
712 }
713 
714 /* Register address family specific functions. */
715 int sctp_register_af(struct sctp_af *af)
716 {
717 	switch (af->sa_family) {
718 	case AF_INET:
719 		if (sctp_af_v4_specific)
720 			return 0;
721 		sctp_af_v4_specific = af;
722 		break;
723 	case AF_INET6:
724 		if (sctp_af_v6_specific)
725 			return 0;
726 		sctp_af_v6_specific = af;
727 		break;
728 	default:
729 		return 0;
730 	}
731 
732 	INIT_LIST_HEAD(&af->list);
733 	list_add_tail(&af->list, &sctp_address_families);
734 	return 1;
735 }
736 
737 /* Get the table of functions for manipulating a particular address
738  * family.
739  */
740 struct sctp_af *sctp_get_af_specific(sa_family_t family)
741 {
742 	switch (family) {
743 	case AF_INET:
744 		return sctp_af_v4_specific;
745 	case AF_INET6:
746 		return sctp_af_v6_specific;
747 	default:
748 		return NULL;
749 	}
750 }
751 
752 /* Common code to initialize a AF_INET msg_name. */
753 static void sctp_inet_msgname(char *msgname, int *addr_len)
754 {
755 	struct sockaddr_in *sin;
756 
757 	sin = (struct sockaddr_in *)msgname;
758 	*addr_len = sizeof(struct sockaddr_in);
759 	sin->sin_family = AF_INET;
760 	memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
761 }
762 
763 /* Copy the primary address of the peer primary address as the msg_name. */
764 static void sctp_inet_event_msgname(struct sctp_ulpevent *event, char *msgname,
765 				    int *addr_len)
766 {
767 	struct sockaddr_in *sin, *sinfrom;
768 
769 	if (msgname) {
770 		struct sctp_association *asoc;
771 
772 		asoc = event->asoc;
773 		sctp_inet_msgname(msgname, addr_len);
774 		sin = (struct sockaddr_in *)msgname;
775 		sinfrom = &asoc->peer.primary_addr.v4;
776 		sin->sin_port = htons(asoc->peer.port);
777 		sin->sin_addr.s_addr = sinfrom->sin_addr.s_addr;
778 	}
779 }
780 
781 /* Initialize and copy out a msgname from an inbound skb. */
782 static void sctp_inet_skb_msgname(struct sk_buff *skb, char *msgname, int *len)
783 {
784 	if (msgname) {
785 		struct sctphdr *sh = sctp_hdr(skb);
786 		struct sockaddr_in *sin = (struct sockaddr_in *)msgname;
787 
788 		sctp_inet_msgname(msgname, len);
789 		sin->sin_port = sh->source;
790 		sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
791 	}
792 }
793 
794 /* Do we support this AF? */
795 static int sctp_inet_af_supported(sa_family_t family, struct sctp_sock *sp)
796 {
797 	/* PF_INET only supports AF_INET addresses. */
798 	return (AF_INET == family);
799 }
800 
801 /* Address matching with wildcards allowed. */
802 static int sctp_inet_cmp_addr(const union sctp_addr *addr1,
803 			      const union sctp_addr *addr2,
804 			      struct sctp_sock *opt)
805 {
806 	/* PF_INET only supports AF_INET addresses. */
807 	if (addr1->sa.sa_family != addr2->sa.sa_family)
808 		return 0;
809 	if (htonl(INADDR_ANY) == addr1->v4.sin_addr.s_addr ||
810 	    htonl(INADDR_ANY) == addr2->v4.sin_addr.s_addr)
811 		return 1;
812 	if (addr1->v4.sin_addr.s_addr == addr2->v4.sin_addr.s_addr)
813 		return 1;
814 
815 	return 0;
816 }
817 
818 /* Verify that provided sockaddr looks bindable.  Common verification has
819  * already been taken care of.
820  */
821 static int sctp_inet_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
822 {
823 	return sctp_v4_available(addr, opt);
824 }
825 
826 /* Verify that sockaddr looks sendable.  Common verification has already
827  * been taken care of.
828  */
829 static int sctp_inet_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
830 {
831 	return 1;
832 }
833 
834 /* Fill in Supported Address Type information for INIT and INIT-ACK
835  * chunks.  Returns number of addresses supported.
836  */
837 static int sctp_inet_supported_addrs(const struct sctp_sock *opt,
838 				     __be16 *types)
839 {
840 	types[0] = SCTP_PARAM_IPV4_ADDRESS;
841 	return 1;
842 }
843 
844 /* Wrapper routine that calls the ip transmit routine. */
845 static inline int sctp_v4_xmit(struct sk_buff *skb,
846 			       struct sctp_transport *transport)
847 {
848 	struct inet_sock *inet = inet_sk(skb->sk);
849 
850 	SCTP_DEBUG_PRINTK("%s: skb:%p, len:%d, src:%pI4, dst:%pI4\n",
851 			  __func__, skb, skb->len,
852 			  &skb_rtable(skb)->rt_src,
853 			  &skb_rtable(skb)->rt_dst);
854 
855 	inet->pmtudisc = transport->param_flags & SPP_PMTUD_ENABLE ?
856 			 IP_PMTUDISC_DO : IP_PMTUDISC_DONT;
857 
858 	SCTP_INC_STATS(SCTP_MIB_OUTSCTPPACKS);
859 	return ip_queue_xmit(skb, 0);
860 }
861 
862 static struct sctp_af sctp_af_inet;
863 
864 static struct sctp_pf sctp_pf_inet = {
865 	.event_msgname = sctp_inet_event_msgname,
866 	.skb_msgname   = sctp_inet_skb_msgname,
867 	.af_supported  = sctp_inet_af_supported,
868 	.cmp_addr      = sctp_inet_cmp_addr,
869 	.bind_verify   = sctp_inet_bind_verify,
870 	.send_verify   = sctp_inet_send_verify,
871 	.supported_addrs = sctp_inet_supported_addrs,
872 	.create_accept_sk = sctp_v4_create_accept_sk,
873 	.addr_v4map	= sctp_v4_addr_v4map,
874 	.af            = &sctp_af_inet
875 };
876 
877 /* Notifier for inetaddr addition/deletion events.  */
878 static struct notifier_block sctp_inetaddr_notifier = {
879 	.notifier_call = sctp_inetaddr_event,
880 };
881 
882 /* Socket operations.  */
883 static const struct proto_ops inet_seqpacket_ops = {
884 	.family		   = PF_INET,
885 	.owner		   = THIS_MODULE,
886 	.release	   = inet_release,	/* Needs to be wrapped... */
887 	.bind		   = inet_bind,
888 	.connect	   = inet_dgram_connect,
889 	.socketpair	   = sock_no_socketpair,
890 	.accept		   = inet_accept,
891 	.getname	   = inet_getname,	/* Semantics are different.  */
892 	.poll		   = sctp_poll,
893 	.ioctl		   = inet_ioctl,
894 	.listen		   = sctp_inet_listen,
895 	.shutdown	   = inet_shutdown,	/* Looks harmless.  */
896 	.setsockopt	   = sock_common_setsockopt, /* IP_SOL IP_OPTION is a problem */
897 	.getsockopt	   = sock_common_getsockopt,
898 	.sendmsg	   = inet_sendmsg,
899 	.recvmsg	   = sock_common_recvmsg,
900 	.mmap		   = sock_no_mmap,
901 	.sendpage	   = sock_no_sendpage,
902 #ifdef CONFIG_COMPAT
903 	.compat_setsockopt = compat_sock_common_setsockopt,
904 	.compat_getsockopt = compat_sock_common_getsockopt,
905 #endif
906 };
907 
908 /* Registration with AF_INET family.  */
909 static struct inet_protosw sctp_seqpacket_protosw = {
910 	.type       = SOCK_SEQPACKET,
911 	.protocol   = IPPROTO_SCTP,
912 	.prot       = &sctp_prot,
913 	.ops        = &inet_seqpacket_ops,
914 	.capability = -1,
915 	.no_check   = 0,
916 	.flags      = SCTP_PROTOSW_FLAG
917 };
918 static struct inet_protosw sctp_stream_protosw = {
919 	.type       = SOCK_STREAM,
920 	.protocol   = IPPROTO_SCTP,
921 	.prot       = &sctp_prot,
922 	.ops        = &inet_seqpacket_ops,
923 	.capability = -1,
924 	.no_check   = 0,
925 	.flags      = SCTP_PROTOSW_FLAG
926 };
927 
928 /* Register with IP layer.  */
929 static struct net_protocol sctp_protocol = {
930 	.handler     = sctp_rcv,
931 	.err_handler = sctp_v4_err,
932 	.no_policy   = 1,
933 };
934 
935 /* IPv4 address related functions.  */
936 static struct sctp_af sctp_af_inet = {
937 	.sa_family	   = AF_INET,
938 	.sctp_xmit	   = sctp_v4_xmit,
939 	.setsockopt	   = ip_setsockopt,
940 	.getsockopt	   = ip_getsockopt,
941 	.get_dst	   = sctp_v4_get_dst,
942 	.get_saddr	   = sctp_v4_get_saddr,
943 	.copy_addrlist	   = sctp_v4_copy_addrlist,
944 	.from_skb	   = sctp_v4_from_skb,
945 	.from_sk	   = sctp_v4_from_sk,
946 	.to_sk_saddr	   = sctp_v4_to_sk_saddr,
947 	.to_sk_daddr	   = sctp_v4_to_sk_daddr,
948 	.from_addr_param   = sctp_v4_from_addr_param,
949 	.to_addr_param	   = sctp_v4_to_addr_param,
950 	.dst_saddr	   = sctp_v4_dst_saddr,
951 	.cmp_addr	   = sctp_v4_cmp_addr,
952 	.addr_valid	   = sctp_v4_addr_valid,
953 	.inaddr_any	   = sctp_v4_inaddr_any,
954 	.is_any		   = sctp_v4_is_any,
955 	.available	   = sctp_v4_available,
956 	.scope		   = sctp_v4_scope,
957 	.skb_iif	   = sctp_v4_skb_iif,
958 	.is_ce		   = sctp_v4_is_ce,
959 	.seq_dump_addr	   = sctp_v4_seq_dump_addr,
960 	.ecn_capable	   = sctp_v4_ecn_capable,
961 	.net_header_len	   = sizeof(struct iphdr),
962 	.sockaddr_len	   = sizeof(struct sockaddr_in),
963 #ifdef CONFIG_COMPAT
964 	.compat_setsockopt = compat_ip_setsockopt,
965 	.compat_getsockopt = compat_ip_getsockopt,
966 #endif
967 };
968 
969 struct sctp_pf *sctp_get_pf_specific(sa_family_t family) {
970 
971 	switch (family) {
972 	case PF_INET:
973 		return sctp_pf_inet_specific;
974 	case PF_INET6:
975 		return sctp_pf_inet6_specific;
976 	default:
977 		return NULL;
978 	}
979 }
980 
981 /* Register the PF specific function table.  */
982 int sctp_register_pf(struct sctp_pf *pf, sa_family_t family)
983 {
984 	switch (family) {
985 	case PF_INET:
986 		if (sctp_pf_inet_specific)
987 			return 0;
988 		sctp_pf_inet_specific = pf;
989 		break;
990 	case PF_INET6:
991 		if (sctp_pf_inet6_specific)
992 			return 0;
993 		sctp_pf_inet6_specific = pf;
994 		break;
995 	default:
996 		return 0;
997 	}
998 	return 1;
999 }
1000 
1001 static inline int init_sctp_mibs(void)
1002 {
1003 	return snmp_mib_init((void**)sctp_statistics, sizeof(struct sctp_mib));
1004 }
1005 
1006 static inline void cleanup_sctp_mibs(void)
1007 {
1008 	snmp_mib_free((void**)sctp_statistics);
1009 }
1010 
1011 static void sctp_v4_pf_init(void)
1012 {
1013 	/* Initialize the SCTP specific PF functions. */
1014 	sctp_register_pf(&sctp_pf_inet, PF_INET);
1015 	sctp_register_af(&sctp_af_inet);
1016 }
1017 
1018 static void sctp_v4_pf_exit(void)
1019 {
1020 	list_del(&sctp_af_inet.list);
1021 }
1022 
1023 static int sctp_v4_protosw_init(void)
1024 {
1025 	int rc;
1026 
1027 	rc = proto_register(&sctp_prot, 1);
1028 	if (rc)
1029 		return rc;
1030 
1031 	/* Register SCTP(UDP and TCP style) with socket layer.  */
1032 	inet_register_protosw(&sctp_seqpacket_protosw);
1033 	inet_register_protosw(&sctp_stream_protosw);
1034 
1035 	return 0;
1036 }
1037 
1038 static void sctp_v4_protosw_exit(void)
1039 {
1040 	inet_unregister_protosw(&sctp_stream_protosw);
1041 	inet_unregister_protosw(&sctp_seqpacket_protosw);
1042 	proto_unregister(&sctp_prot);
1043 }
1044 
1045 static int sctp_v4_add_protocol(void)
1046 {
1047 	/* Register notifier for inet address additions/deletions. */
1048 	register_inetaddr_notifier(&sctp_inetaddr_notifier);
1049 
1050 	/* Register SCTP with inet layer.  */
1051 	if (inet_add_protocol(&sctp_protocol, IPPROTO_SCTP) < 0)
1052 		return -EAGAIN;
1053 
1054 	return 0;
1055 }
1056 
1057 static void sctp_v4_del_protocol(void)
1058 {
1059 	inet_del_protocol(&sctp_protocol, IPPROTO_SCTP);
1060 	unregister_inetaddr_notifier(&sctp_inetaddr_notifier);
1061 }
1062 
1063 /* Initialize the universe into something sensible.  */
1064 SCTP_STATIC __init int sctp_init(void)
1065 {
1066 	int i;
1067 	int status = -EINVAL;
1068 	unsigned long goal;
1069 	unsigned long limit;
1070 	unsigned long nr_pages;
1071 	int max_share;
1072 	int order;
1073 
1074 	/* SCTP_DEBUG sanity check. */
1075 	if (!sctp_sanity_check())
1076 		goto out;
1077 
1078 	/* Allocate bind_bucket and chunk caches. */
1079 	status = -ENOBUFS;
1080 	sctp_bucket_cachep = kmem_cache_create("sctp_bind_bucket",
1081 					       sizeof(struct sctp_bind_bucket),
1082 					       0, SLAB_HWCACHE_ALIGN,
1083 					       NULL);
1084 	if (!sctp_bucket_cachep)
1085 		goto out;
1086 
1087 	sctp_chunk_cachep = kmem_cache_create("sctp_chunk",
1088 					       sizeof(struct sctp_chunk),
1089 					       0, SLAB_HWCACHE_ALIGN,
1090 					       NULL);
1091 	if (!sctp_chunk_cachep)
1092 		goto err_chunk_cachep;
1093 
1094 	/* Allocate and initialise sctp mibs.  */
1095 	status = init_sctp_mibs();
1096 	if (status)
1097 		goto err_init_mibs;
1098 
1099 	/* Initialize proc fs directory.  */
1100 	status = sctp_proc_init();
1101 	if (status)
1102 		goto err_init_proc;
1103 
1104 	/* Initialize object count debugging.  */
1105 	sctp_dbg_objcnt_init();
1106 
1107 	/*
1108 	 * 14. Suggested SCTP Protocol Parameter Values
1109 	 */
1110 	/* The following protocol parameters are RECOMMENDED:  */
1111 	/* RTO.Initial              - 3  seconds */
1112 	sctp_rto_initial		= SCTP_RTO_INITIAL;
1113 	/* RTO.Min                  - 1  second */
1114 	sctp_rto_min	 		= SCTP_RTO_MIN;
1115 	/* RTO.Max                 -  60 seconds */
1116 	sctp_rto_max 			= SCTP_RTO_MAX;
1117 	/* RTO.Alpha                - 1/8 */
1118 	sctp_rto_alpha	        	= SCTP_RTO_ALPHA;
1119 	/* RTO.Beta                 - 1/4 */
1120 	sctp_rto_beta			= SCTP_RTO_BETA;
1121 
1122 	/* Valid.Cookie.Life        - 60  seconds */
1123 	sctp_valid_cookie_life		= SCTP_DEFAULT_COOKIE_LIFE;
1124 
1125 	/* Whether Cookie Preservative is enabled(1) or not(0) */
1126 	sctp_cookie_preserve_enable 	= 1;
1127 
1128 	/* Max.Burst		    - 4 */
1129 	sctp_max_burst 			= SCTP_DEFAULT_MAX_BURST;
1130 
1131 	/* Association.Max.Retrans  - 10 attempts
1132 	 * Path.Max.Retrans         - 5  attempts (per destination address)
1133 	 * Max.Init.Retransmits     - 8  attempts
1134 	 */
1135 	sctp_max_retrans_association 	= 10;
1136 	sctp_max_retrans_path		= 5;
1137 	sctp_max_retrans_init		= 8;
1138 
1139 	/* Sendbuffer growth	    - do per-socket accounting */
1140 	sctp_sndbuf_policy		= 0;
1141 
1142 	/* Rcvbuffer growth	    - do per-socket accounting */
1143 	sctp_rcvbuf_policy		= 0;
1144 
1145 	/* HB.interval              - 30 seconds */
1146 	sctp_hb_interval		= SCTP_DEFAULT_TIMEOUT_HEARTBEAT;
1147 
1148 	/* delayed SACK timeout */
1149 	sctp_sack_timeout		= SCTP_DEFAULT_TIMEOUT_SACK;
1150 
1151 	/* Implementation specific variables. */
1152 
1153 	/* Initialize default stream count setup information. */
1154 	sctp_max_instreams    		= SCTP_DEFAULT_INSTREAMS;
1155 	sctp_max_outstreams   		= SCTP_DEFAULT_OUTSTREAMS;
1156 
1157 	/* Initialize handle used for association ids. */
1158 	idr_init(&sctp_assocs_id);
1159 
1160 	/* Set the pressure threshold to be a fraction of global memory that
1161 	 * is up to 1/2 at 256 MB, decreasing toward zero with the amount of
1162 	 * memory, with a floor of 128 pages.
1163 	 * Note this initalizes the data in sctpv6_prot too
1164 	 * Unabashedly stolen from tcp_init
1165 	 */
1166 	nr_pages = totalram_pages - totalhigh_pages;
1167 	limit = min(nr_pages, 1UL<<(28-PAGE_SHIFT)) >> (20-PAGE_SHIFT);
1168 	limit = (limit * (nr_pages >> (20-PAGE_SHIFT))) >> (PAGE_SHIFT-11);
1169 	limit = max(limit, 128UL);
1170 	sysctl_sctp_mem[0] = limit / 4 * 3;
1171 	sysctl_sctp_mem[1] = limit;
1172 	sysctl_sctp_mem[2] = sysctl_sctp_mem[0] * 2;
1173 
1174 	/* Set per-socket limits to no more than 1/128 the pressure threshold*/
1175 	limit = (sysctl_sctp_mem[1]) << (PAGE_SHIFT - 7);
1176 	max_share = min(4UL*1024*1024, limit);
1177 
1178 	sysctl_sctp_rmem[0] = SK_MEM_QUANTUM; /* give each asoc 1 page min */
1179 	sysctl_sctp_rmem[1] = (1500 *(sizeof(struct sk_buff) + 1));
1180 	sysctl_sctp_rmem[2] = max(sysctl_sctp_rmem[1], max_share);
1181 
1182 	sysctl_sctp_wmem[0] = SK_MEM_QUANTUM;
1183 	sysctl_sctp_wmem[1] = 16*1024;
1184 	sysctl_sctp_wmem[2] = max(64*1024, max_share);
1185 
1186 	/* Size and allocate the association hash table.
1187 	 * The methodology is similar to that of the tcp hash tables.
1188 	 */
1189 	if (num_physpages >= (128 * 1024))
1190 		goal = num_physpages >> (22 - PAGE_SHIFT);
1191 	else
1192 		goal = num_physpages >> (24 - PAGE_SHIFT);
1193 
1194 	for (order = 0; (1UL << order) < goal; order++)
1195 		;
1196 
1197 	do {
1198 		sctp_assoc_hashsize = (1UL << order) * PAGE_SIZE /
1199 					sizeof(struct sctp_hashbucket);
1200 		if ((sctp_assoc_hashsize > (64 * 1024)) && order > 0)
1201 			continue;
1202 		sctp_assoc_hashtable = (struct sctp_hashbucket *)
1203 					__get_free_pages(GFP_ATOMIC, order);
1204 	} while (!sctp_assoc_hashtable && --order > 0);
1205 	if (!sctp_assoc_hashtable) {
1206 		printk(KERN_ERR "SCTP: Failed association hash alloc.\n");
1207 		status = -ENOMEM;
1208 		goto err_ahash_alloc;
1209 	}
1210 	for (i = 0; i < sctp_assoc_hashsize; i++) {
1211 		rwlock_init(&sctp_assoc_hashtable[i].lock);
1212 		INIT_HLIST_HEAD(&sctp_assoc_hashtable[i].chain);
1213 	}
1214 
1215 	/* Allocate and initialize the endpoint hash table.  */
1216 	sctp_ep_hashsize = 64;
1217 	sctp_ep_hashtable = (struct sctp_hashbucket *)
1218 		kmalloc(64 * sizeof(struct sctp_hashbucket), GFP_KERNEL);
1219 	if (!sctp_ep_hashtable) {
1220 		printk(KERN_ERR "SCTP: Failed endpoint_hash alloc.\n");
1221 		status = -ENOMEM;
1222 		goto err_ehash_alloc;
1223 	}
1224 	for (i = 0; i < sctp_ep_hashsize; i++) {
1225 		rwlock_init(&sctp_ep_hashtable[i].lock);
1226 		INIT_HLIST_HEAD(&sctp_ep_hashtable[i].chain);
1227 	}
1228 
1229 	/* Allocate and initialize the SCTP port hash table.  */
1230 	do {
1231 		sctp_port_hashsize = (1UL << order) * PAGE_SIZE /
1232 					sizeof(struct sctp_bind_hashbucket);
1233 		if ((sctp_port_hashsize > (64 * 1024)) && order > 0)
1234 			continue;
1235 		sctp_port_hashtable = (struct sctp_bind_hashbucket *)
1236 					__get_free_pages(GFP_ATOMIC, order);
1237 	} while (!sctp_port_hashtable && --order > 0);
1238 	if (!sctp_port_hashtable) {
1239 		printk(KERN_ERR "SCTP: Failed bind hash alloc.");
1240 		status = -ENOMEM;
1241 		goto err_bhash_alloc;
1242 	}
1243 	for (i = 0; i < sctp_port_hashsize; i++) {
1244 		spin_lock_init(&sctp_port_hashtable[i].lock);
1245 		INIT_HLIST_HEAD(&sctp_port_hashtable[i].chain);
1246 	}
1247 
1248 	printk(KERN_INFO "SCTP: Hash tables configured "
1249 			 "(established %d bind %d)\n",
1250 		sctp_assoc_hashsize, sctp_port_hashsize);
1251 
1252 	/* Disable ADDIP by default. */
1253 	sctp_addip_enable = 0;
1254 	sctp_addip_noauth = 0;
1255 
1256 	/* Enable PR-SCTP by default. */
1257 	sctp_prsctp_enable = 1;
1258 
1259 	/* Disable AUTH by default. */
1260 	sctp_auth_enable = 0;
1261 
1262 	sctp_sysctl_register();
1263 
1264 	INIT_LIST_HEAD(&sctp_address_families);
1265 	sctp_v4_pf_init();
1266 	sctp_v6_pf_init();
1267 
1268 	/* Initialize the local address list. */
1269 	INIT_LIST_HEAD(&sctp_local_addr_list);
1270 	spin_lock_init(&sctp_local_addr_lock);
1271 	sctp_get_local_addr_list();
1272 
1273 	status = sctp_v4_protosw_init();
1274 
1275 	if (status)
1276 		goto err_protosw_init;
1277 
1278 	status = sctp_v6_protosw_init();
1279 	if (status)
1280 		goto err_v6_protosw_init;
1281 
1282 	/* Initialize the control inode/socket for handling OOTB packets.  */
1283 	if ((status = sctp_ctl_sock_init())) {
1284 		printk (KERN_ERR
1285 			"SCTP: Failed to initialize the SCTP control sock.\n");
1286 		goto err_ctl_sock_init;
1287 	}
1288 
1289 	status = sctp_v4_add_protocol();
1290 	if (status)
1291 		goto err_add_protocol;
1292 
1293 	/* Register SCTP with inet6 layer.  */
1294 	status = sctp_v6_add_protocol();
1295 	if (status)
1296 		goto err_v6_add_protocol;
1297 
1298 	status = 0;
1299 out:
1300 	return status;
1301 err_v6_add_protocol:
1302 	sctp_v4_del_protocol();
1303 err_add_protocol:
1304 	inet_ctl_sock_destroy(sctp_ctl_sock);
1305 err_ctl_sock_init:
1306 	sctp_v6_protosw_exit();
1307 err_v6_protosw_init:
1308 	sctp_v4_protosw_exit();
1309 err_protosw_init:
1310 	sctp_free_local_addr_list();
1311 	sctp_v4_pf_exit();
1312 	sctp_v6_pf_exit();
1313 	sctp_sysctl_unregister();
1314 	free_pages((unsigned long)sctp_port_hashtable,
1315 		   get_order(sctp_port_hashsize *
1316 			     sizeof(struct sctp_bind_hashbucket)));
1317 err_bhash_alloc:
1318 	kfree(sctp_ep_hashtable);
1319 err_ehash_alloc:
1320 	free_pages((unsigned long)sctp_assoc_hashtable,
1321 		   get_order(sctp_assoc_hashsize *
1322 			     sizeof(struct sctp_hashbucket)));
1323 err_ahash_alloc:
1324 	sctp_dbg_objcnt_exit();
1325 	sctp_proc_exit();
1326 err_init_proc:
1327 	cleanup_sctp_mibs();
1328 err_init_mibs:
1329 	kmem_cache_destroy(sctp_chunk_cachep);
1330 err_chunk_cachep:
1331 	kmem_cache_destroy(sctp_bucket_cachep);
1332 	goto out;
1333 }
1334 
1335 /* Exit handler for the SCTP protocol.  */
1336 SCTP_STATIC __exit void sctp_exit(void)
1337 {
1338 	/* BUG.  This should probably do something useful like clean
1339 	 * up all the remaining associations and all that memory.
1340 	 */
1341 
1342 	/* Unregister with inet6/inet layers. */
1343 	sctp_v6_del_protocol();
1344 	sctp_v4_del_protocol();
1345 
1346 	/* Free the control endpoint.  */
1347 	inet_ctl_sock_destroy(sctp_ctl_sock);
1348 
1349 	/* Free protosw registrations */
1350 	sctp_v6_protosw_exit();
1351 	sctp_v4_protosw_exit();
1352 
1353 	/* Free the local address list.  */
1354 	sctp_free_local_addr_list();
1355 
1356 	/* Unregister with socket layer. */
1357 	sctp_v6_pf_exit();
1358 	sctp_v4_pf_exit();
1359 
1360 	sctp_sysctl_unregister();
1361 
1362 	free_pages((unsigned long)sctp_assoc_hashtable,
1363 		   get_order(sctp_assoc_hashsize *
1364 			     sizeof(struct sctp_hashbucket)));
1365 	kfree(sctp_ep_hashtable);
1366 	free_pages((unsigned long)sctp_port_hashtable,
1367 		   get_order(sctp_port_hashsize *
1368 			     sizeof(struct sctp_bind_hashbucket)));
1369 
1370 	sctp_dbg_objcnt_exit();
1371 	sctp_proc_exit();
1372 	cleanup_sctp_mibs();
1373 
1374 	rcu_barrier(); /* Wait for completion of call_rcu()'s */
1375 
1376 	kmem_cache_destroy(sctp_chunk_cachep);
1377 	kmem_cache_destroy(sctp_bucket_cachep);
1378 }
1379 
1380 module_init(sctp_init);
1381 module_exit(sctp_exit);
1382 
1383 /*
1384  * __stringify doesn't likes enums, so use IPPROTO_SCTP value (132) directly.
1385  */
1386 MODULE_ALIAS("net-pf-" __stringify(PF_INET) "-proto-132");
1387 MODULE_ALIAS("net-pf-" __stringify(PF_INET6) "-proto-132");
1388 MODULE_AUTHOR("Linux Kernel SCTP developers <lksctp-developers@lists.sourceforge.net>");
1389 MODULE_DESCRIPTION("Support for the SCTP protocol (RFC2960)");
1390 module_param_named(no_checksums, sctp_checksum_disable, bool, 0644);
1391 MODULE_PARM_DESC(no_checksums, "Disable checksums computing and verification");
1392 MODULE_LICENSE("GPL");
1393