xref: /openbmc/linux/net/sctp/protocol.c (revision 6aa7de05)
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, see
27  * <http://www.gnu.org/licenses/>.
28  *
29  * Please send any bug reports or fixes you make to the
30  * email address(es):
31  *    lksctp developers <linux-sctp@vger.kernel.org>
32  *
33  * Written or modified by:
34  *    La Monte H.P. Yarroll <piggy@acm.org>
35  *    Karl Knutson <karl@athena.chicago.il.us>
36  *    Jon Grimm <jgrimm@us.ibm.com>
37  *    Sridhar Samudrala <sri@us.ibm.com>
38  *    Daisy Chang <daisyc@us.ibm.com>
39  *    Ardelle Fan <ardelle.fan@intel.com>
40  */
41 
42 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
43 
44 #include <linux/module.h>
45 #include <linux/init.h>
46 #include <linux/netdevice.h>
47 #include <linux/inetdevice.h>
48 #include <linux/seq_file.h>
49 #include <linux/bootmem.h>
50 #include <linux/highmem.h>
51 #include <linux/swap.h>
52 #include <linux/slab.h>
53 #include <net/net_namespace.h>
54 #include <net/protocol.h>
55 #include <net/ip.h>
56 #include <net/ipv6.h>
57 #include <net/route.h>
58 #include <net/sctp/sctp.h>
59 #include <net/addrconf.h>
60 #include <net/inet_common.h>
61 #include <net/inet_ecn.h>
62 
63 #define MAX_SCTP_PORT_HASH_ENTRIES (64 * 1024)
64 
65 /* Global data structures. */
66 struct sctp_globals sctp_globals __read_mostly;
67 
68 struct idr sctp_assocs_id;
69 DEFINE_SPINLOCK(sctp_assocs_id_lock);
70 
71 static struct sctp_pf *sctp_pf_inet6_specific;
72 static struct sctp_pf *sctp_pf_inet_specific;
73 static struct sctp_af *sctp_af_v4_specific;
74 static struct sctp_af *sctp_af_v6_specific;
75 
76 struct kmem_cache *sctp_chunk_cachep __read_mostly;
77 struct kmem_cache *sctp_bucket_cachep __read_mostly;
78 
79 long sysctl_sctp_mem[3];
80 int sysctl_sctp_rmem[3];
81 int sysctl_sctp_wmem[3];
82 
83 /* Set up the proc fs entry for the SCTP protocol. */
84 static int __net_init sctp_proc_init(struct net *net)
85 {
86 #ifdef CONFIG_PROC_FS
87 	net->sctp.proc_net_sctp = proc_net_mkdir(net, "sctp", net->proc_net);
88 	if (!net->sctp.proc_net_sctp)
89 		goto out_proc_net_sctp;
90 	if (sctp_snmp_proc_init(net))
91 		goto out_snmp_proc_init;
92 	if (sctp_eps_proc_init(net))
93 		goto out_eps_proc_init;
94 	if (sctp_assocs_proc_init(net))
95 		goto out_assocs_proc_init;
96 	if (sctp_remaddr_proc_init(net))
97 		goto out_remaddr_proc_init;
98 
99 	return 0;
100 
101 out_remaddr_proc_init:
102 	sctp_assocs_proc_exit(net);
103 out_assocs_proc_init:
104 	sctp_eps_proc_exit(net);
105 out_eps_proc_init:
106 	sctp_snmp_proc_exit(net);
107 out_snmp_proc_init:
108 	remove_proc_entry("sctp", net->proc_net);
109 	net->sctp.proc_net_sctp = NULL;
110 out_proc_net_sctp:
111 	return -ENOMEM;
112 #endif /* CONFIG_PROC_FS */
113 	return 0;
114 }
115 
116 /* Clean up the proc fs entry for the SCTP protocol.
117  * Note: Do not make this __exit as it is used in the init error
118  * path.
119  */
120 static void sctp_proc_exit(struct net *net)
121 {
122 #ifdef CONFIG_PROC_FS
123 	sctp_snmp_proc_exit(net);
124 	sctp_eps_proc_exit(net);
125 	sctp_assocs_proc_exit(net);
126 	sctp_remaddr_proc_exit(net);
127 
128 	remove_proc_entry("sctp", net->proc_net);
129 	net->sctp.proc_net_sctp = NULL;
130 #endif
131 }
132 
133 /* Private helper to extract ipv4 address and stash them in
134  * the protocol structure.
135  */
136 static void sctp_v4_copy_addrlist(struct list_head *addrlist,
137 				  struct net_device *dev)
138 {
139 	struct in_device *in_dev;
140 	struct in_ifaddr *ifa;
141 	struct sctp_sockaddr_entry *addr;
142 
143 	rcu_read_lock();
144 	if ((in_dev = __in_dev_get_rcu(dev)) == NULL) {
145 		rcu_read_unlock();
146 		return;
147 	}
148 
149 	for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
150 		/* Add the address to the local list.  */
151 		addr = kzalloc(sizeof(*addr), GFP_ATOMIC);
152 		if (addr) {
153 			addr->a.v4.sin_family = AF_INET;
154 			addr->a.v4.sin_port = 0;
155 			addr->a.v4.sin_addr.s_addr = ifa->ifa_local;
156 			addr->valid = 1;
157 			INIT_LIST_HEAD(&addr->list);
158 			list_add_tail(&addr->list, addrlist);
159 		}
160 	}
161 
162 	rcu_read_unlock();
163 }
164 
165 /* Extract our IP addresses from the system and stash them in the
166  * protocol structure.
167  */
168 static void sctp_get_local_addr_list(struct net *net)
169 {
170 	struct net_device *dev;
171 	struct list_head *pos;
172 	struct sctp_af *af;
173 
174 	rcu_read_lock();
175 	for_each_netdev_rcu(net, dev) {
176 		list_for_each(pos, &sctp_address_families) {
177 			af = list_entry(pos, struct sctp_af, list);
178 			af->copy_addrlist(&net->sctp.local_addr_list, dev);
179 		}
180 	}
181 	rcu_read_unlock();
182 }
183 
184 /* Free the existing local addresses.  */
185 static void sctp_free_local_addr_list(struct net *net)
186 {
187 	struct sctp_sockaddr_entry *addr;
188 	struct list_head *pos, *temp;
189 
190 	list_for_each_safe(pos, temp, &net->sctp.local_addr_list) {
191 		addr = list_entry(pos, struct sctp_sockaddr_entry, list);
192 		list_del(pos);
193 		kfree(addr);
194 	}
195 }
196 
197 /* Copy the local addresses which are valid for 'scope' into 'bp'.  */
198 int sctp_copy_local_addr_list(struct net *net, struct sctp_bind_addr *bp,
199 			      enum sctp_scope scope, gfp_t gfp, int copy_flags)
200 {
201 	struct sctp_sockaddr_entry *addr;
202 	union sctp_addr laddr;
203 	int error = 0;
204 
205 	rcu_read_lock();
206 	list_for_each_entry_rcu(addr, &net->sctp.local_addr_list, list) {
207 		if (!addr->valid)
208 			continue;
209 		if (!sctp_in_scope(net, &addr->a, scope))
210 			continue;
211 
212 		/* Now that the address is in scope, check to see if
213 		 * the address type is really supported by the local
214 		 * sock as well as the remote peer.
215 		 */
216 		if (addr->a.sa.sa_family == AF_INET &&
217 		    !(copy_flags & SCTP_ADDR4_PEERSUPP))
218 			continue;
219 		if (addr->a.sa.sa_family == AF_INET6 &&
220 		    (!(copy_flags & SCTP_ADDR6_ALLOWED) ||
221 		     !(copy_flags & SCTP_ADDR6_PEERSUPP)))
222 			continue;
223 
224 		laddr = addr->a;
225 		/* also works for setting ipv6 address port */
226 		laddr.v4.sin_port = htons(bp->port);
227 		if (sctp_bind_addr_state(bp, &laddr) != -1)
228 			continue;
229 
230 		error = sctp_add_bind_addr(bp, &addr->a, sizeof(addr->a),
231 					   SCTP_ADDR_SRC, GFP_ATOMIC);
232 		if (error)
233 			break;
234 	}
235 
236 	rcu_read_unlock();
237 	return error;
238 }
239 
240 /* Initialize a sctp_addr from in incoming skb.  */
241 static void sctp_v4_from_skb(union sctp_addr *addr, struct sk_buff *skb,
242 			     int is_saddr)
243 {
244 	/* Always called on head skb, so this is safe */
245 	struct sctphdr *sh = sctp_hdr(skb);
246 	struct sockaddr_in *sa = &addr->v4;
247 
248 	addr->v4.sin_family = AF_INET;
249 
250 	if (is_saddr) {
251 		sa->sin_port = sh->source;
252 		sa->sin_addr.s_addr = ip_hdr(skb)->saddr;
253 	} else {
254 		sa->sin_port = sh->dest;
255 		sa->sin_addr.s_addr = ip_hdr(skb)->daddr;
256 	}
257 }
258 
259 /* Initialize an sctp_addr from a socket. */
260 static void sctp_v4_from_sk(union sctp_addr *addr, struct sock *sk)
261 {
262 	addr->v4.sin_family = AF_INET;
263 	addr->v4.sin_port = 0;
264 	addr->v4.sin_addr.s_addr = inet_sk(sk)->inet_rcv_saddr;
265 }
266 
267 /* Initialize sk->sk_rcv_saddr from sctp_addr. */
268 static void sctp_v4_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
269 {
270 	inet_sk(sk)->inet_rcv_saddr = addr->v4.sin_addr.s_addr;
271 }
272 
273 /* Initialize sk->sk_daddr from sctp_addr. */
274 static void sctp_v4_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
275 {
276 	inet_sk(sk)->inet_daddr = addr->v4.sin_addr.s_addr;
277 }
278 
279 /* Initialize a sctp_addr from an address parameter. */
280 static void sctp_v4_from_addr_param(union sctp_addr *addr,
281 				    union sctp_addr_param *param,
282 				    __be16 port, int iif)
283 {
284 	addr->v4.sin_family = AF_INET;
285 	addr->v4.sin_port = port;
286 	addr->v4.sin_addr.s_addr = param->v4.addr.s_addr;
287 }
288 
289 /* Initialize an address parameter from a sctp_addr and return the length
290  * of the address parameter.
291  */
292 static int sctp_v4_to_addr_param(const union sctp_addr *addr,
293 				 union sctp_addr_param *param)
294 {
295 	int length = sizeof(struct sctp_ipv4addr_param);
296 
297 	param->v4.param_hdr.type = SCTP_PARAM_IPV4_ADDRESS;
298 	param->v4.param_hdr.length = htons(length);
299 	param->v4.addr.s_addr = addr->v4.sin_addr.s_addr;
300 
301 	return length;
302 }
303 
304 /* Initialize a sctp_addr from a dst_entry. */
305 static void sctp_v4_dst_saddr(union sctp_addr *saddr, struct flowi4 *fl4,
306 			      __be16 port)
307 {
308 	saddr->v4.sin_family = AF_INET;
309 	saddr->v4.sin_port = port;
310 	saddr->v4.sin_addr.s_addr = fl4->saddr;
311 }
312 
313 /* Compare two addresses exactly. */
314 static int sctp_v4_cmp_addr(const union sctp_addr *addr1,
315 			    const union sctp_addr *addr2)
316 {
317 	if (addr1->sa.sa_family != addr2->sa.sa_family)
318 		return 0;
319 	if (addr1->v4.sin_port != addr2->v4.sin_port)
320 		return 0;
321 	if (addr1->v4.sin_addr.s_addr != addr2->v4.sin_addr.s_addr)
322 		return 0;
323 
324 	return 1;
325 }
326 
327 /* Initialize addr struct to INADDR_ANY. */
328 static void sctp_v4_inaddr_any(union sctp_addr *addr, __be16 port)
329 {
330 	addr->v4.sin_family = AF_INET;
331 	addr->v4.sin_addr.s_addr = htonl(INADDR_ANY);
332 	addr->v4.sin_port = port;
333 }
334 
335 /* Is this a wildcard address? */
336 static int sctp_v4_is_any(const union sctp_addr *addr)
337 {
338 	return htonl(INADDR_ANY) == addr->v4.sin_addr.s_addr;
339 }
340 
341 /* This function checks if the address is a valid address to be used for
342  * SCTP binding.
343  *
344  * Output:
345  * Return 0 - If the address is a non-unicast or an illegal address.
346  * Return 1 - If the address is a unicast.
347  */
348 static int sctp_v4_addr_valid(union sctp_addr *addr,
349 			      struct sctp_sock *sp,
350 			      const struct sk_buff *skb)
351 {
352 	/* IPv4 addresses not allowed */
353 	if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
354 		return 0;
355 
356 	/* Is this a non-unicast address or a unusable SCTP address? */
357 	if (IS_IPV4_UNUSABLE_ADDRESS(addr->v4.sin_addr.s_addr))
358 		return 0;
359 
360 	/* Is this a broadcast address? */
361 	if (skb && skb_rtable(skb)->rt_flags & RTCF_BROADCAST)
362 		return 0;
363 
364 	return 1;
365 }
366 
367 /* Should this be available for binding?   */
368 static int sctp_v4_available(union sctp_addr *addr, struct sctp_sock *sp)
369 {
370 	struct net *net = sock_net(&sp->inet.sk);
371 	int ret = inet_addr_type(net, addr->v4.sin_addr.s_addr);
372 
373 
374 	if (addr->v4.sin_addr.s_addr != htonl(INADDR_ANY) &&
375 	   ret != RTN_LOCAL &&
376 	   !sp->inet.freebind &&
377 	   !net->ipv4.sysctl_ip_nonlocal_bind)
378 		return 0;
379 
380 	if (ipv6_only_sock(sctp_opt2sk(sp)))
381 		return 0;
382 
383 	return 1;
384 }
385 
386 /* Checking the loopback, private and other address scopes as defined in
387  * RFC 1918.   The IPv4 scoping is based on the draft for SCTP IPv4
388  * scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>.
389  *
390  * Level 0 - unusable SCTP addresses
391  * Level 1 - loopback address
392  * Level 2 - link-local addresses
393  * Level 3 - private addresses.
394  * Level 4 - global addresses
395  * For INIT and INIT-ACK address list, let L be the level of
396  * of requested destination address, sender and receiver
397  * SHOULD include all of its addresses with level greater
398  * than or equal to L.
399  *
400  * IPv4 scoping can be controlled through sysctl option
401  * net.sctp.addr_scope_policy
402  */
403 static enum sctp_scope sctp_v4_scope(union sctp_addr *addr)
404 {
405 	enum sctp_scope retval;
406 
407 	/* Check for unusable SCTP addresses. */
408 	if (IS_IPV4_UNUSABLE_ADDRESS(addr->v4.sin_addr.s_addr)) {
409 		retval =  SCTP_SCOPE_UNUSABLE;
410 	} else if (ipv4_is_loopback(addr->v4.sin_addr.s_addr)) {
411 		retval = SCTP_SCOPE_LOOPBACK;
412 	} else if (ipv4_is_linklocal_169(addr->v4.sin_addr.s_addr)) {
413 		retval = SCTP_SCOPE_LINK;
414 	} else if (ipv4_is_private_10(addr->v4.sin_addr.s_addr) ||
415 		   ipv4_is_private_172(addr->v4.sin_addr.s_addr) ||
416 		   ipv4_is_private_192(addr->v4.sin_addr.s_addr)) {
417 		retval = SCTP_SCOPE_PRIVATE;
418 	} else {
419 		retval = SCTP_SCOPE_GLOBAL;
420 	}
421 
422 	return retval;
423 }
424 
425 /* Returns a valid dst cache entry for the given source and destination ip
426  * addresses. If an association is passed, trys to get a dst entry with a
427  * source address that matches an address in the bind address list.
428  */
429 static void sctp_v4_get_dst(struct sctp_transport *t, union sctp_addr *saddr,
430 				struct flowi *fl, struct sock *sk)
431 {
432 	struct sctp_association *asoc = t->asoc;
433 	struct rtable *rt;
434 	struct flowi4 *fl4 = &fl->u.ip4;
435 	struct sctp_bind_addr *bp;
436 	struct sctp_sockaddr_entry *laddr;
437 	struct dst_entry *dst = NULL;
438 	union sctp_addr *daddr = &t->ipaddr;
439 	union sctp_addr dst_saddr;
440 
441 	memset(fl4, 0x0, sizeof(struct flowi4));
442 	fl4->daddr  = daddr->v4.sin_addr.s_addr;
443 	fl4->fl4_dport = daddr->v4.sin_port;
444 	fl4->flowi4_proto = IPPROTO_SCTP;
445 	if (asoc) {
446 		fl4->flowi4_tos = RT_CONN_FLAGS(asoc->base.sk);
447 		fl4->flowi4_oif = asoc->base.sk->sk_bound_dev_if;
448 		fl4->fl4_sport = htons(asoc->base.bind_addr.port);
449 	}
450 	if (saddr) {
451 		fl4->saddr = saddr->v4.sin_addr.s_addr;
452 		fl4->fl4_sport = saddr->v4.sin_port;
453 	}
454 
455 	pr_debug("%s: dst:%pI4, src:%pI4 - ", __func__, &fl4->daddr,
456 		 &fl4->saddr);
457 
458 	rt = ip_route_output_key(sock_net(sk), fl4);
459 	if (!IS_ERR(rt))
460 		dst = &rt->dst;
461 
462 	/* If there is no association or if a source address is passed, no
463 	 * more validation is required.
464 	 */
465 	if (!asoc || saddr)
466 		goto out;
467 
468 	bp = &asoc->base.bind_addr;
469 
470 	if (dst) {
471 		/* Walk through the bind address list and look for a bind
472 		 * address that matches the source address of the returned dst.
473 		 */
474 		sctp_v4_dst_saddr(&dst_saddr, fl4, htons(bp->port));
475 		rcu_read_lock();
476 		list_for_each_entry_rcu(laddr, &bp->address_list, list) {
477 			if (!laddr->valid || (laddr->state == SCTP_ADDR_DEL) ||
478 			    (laddr->state != SCTP_ADDR_SRC &&
479 			    !asoc->src_out_of_asoc_ok))
480 				continue;
481 			if (sctp_v4_cmp_addr(&dst_saddr, &laddr->a))
482 				goto out_unlock;
483 		}
484 		rcu_read_unlock();
485 
486 		/* None of the bound addresses match the source address of the
487 		 * dst. So release it.
488 		 */
489 		dst_release(dst);
490 		dst = NULL;
491 	}
492 
493 	/* Walk through the bind address list and try to get a dst that
494 	 * matches a bind address as the source address.
495 	 */
496 	rcu_read_lock();
497 	list_for_each_entry_rcu(laddr, &bp->address_list, list) {
498 		struct net_device *odev;
499 
500 		if (!laddr->valid)
501 			continue;
502 		if (laddr->state != SCTP_ADDR_SRC ||
503 		    AF_INET != laddr->a.sa.sa_family)
504 			continue;
505 
506 		fl4->fl4_sport = laddr->a.v4.sin_port;
507 		flowi4_update_output(fl4,
508 				     asoc->base.sk->sk_bound_dev_if,
509 				     RT_CONN_FLAGS(asoc->base.sk),
510 				     daddr->v4.sin_addr.s_addr,
511 				     laddr->a.v4.sin_addr.s_addr);
512 
513 		rt = ip_route_output_key(sock_net(sk), fl4);
514 		if (IS_ERR(rt))
515 			continue;
516 
517 		if (!dst)
518 			dst = &rt->dst;
519 
520 		/* Ensure the src address belongs to the output
521 		 * interface.
522 		 */
523 		odev = __ip_dev_find(sock_net(sk), laddr->a.v4.sin_addr.s_addr,
524 				     false);
525 		if (!odev || odev->ifindex != fl4->flowi4_oif) {
526 			if (&rt->dst != dst)
527 				dst_release(&rt->dst);
528 			continue;
529 		}
530 
531 		if (dst != &rt->dst)
532 			dst_release(dst);
533 		dst = &rt->dst;
534 		break;
535 	}
536 
537 out_unlock:
538 	rcu_read_unlock();
539 out:
540 	t->dst = dst;
541 	if (dst)
542 		pr_debug("rt_dst:%pI4, rt_src:%pI4\n",
543 			 &fl4->daddr, &fl4->saddr);
544 	else
545 		pr_debug("no route\n");
546 }
547 
548 /* For v4, the source address is cached in the route entry(dst). So no need
549  * to cache it separately and hence this is an empty routine.
550  */
551 static void sctp_v4_get_saddr(struct sctp_sock *sk,
552 			      struct sctp_transport *t,
553 			      struct flowi *fl)
554 {
555 	union sctp_addr *saddr = &t->saddr;
556 	struct rtable *rt = (struct rtable *)t->dst;
557 
558 	if (rt) {
559 		saddr->v4.sin_family = AF_INET;
560 		saddr->v4.sin_addr.s_addr = fl->u.ip4.saddr;
561 	}
562 }
563 
564 /* What interface did this skb arrive on? */
565 static int sctp_v4_skb_iif(const struct sk_buff *skb)
566 {
567 	return inet_iif(skb);
568 }
569 
570 /* Was this packet marked by Explicit Congestion Notification? */
571 static int sctp_v4_is_ce(const struct sk_buff *skb)
572 {
573 	return INET_ECN_is_ce(ip_hdr(skb)->tos);
574 }
575 
576 /* Create and initialize a new sk for the socket returned by accept(). */
577 static struct sock *sctp_v4_create_accept_sk(struct sock *sk,
578 					     struct sctp_association *asoc,
579 					     bool kern)
580 {
581 	struct sock *newsk = sk_alloc(sock_net(sk), PF_INET, GFP_KERNEL,
582 			sk->sk_prot, kern);
583 	struct inet_sock *newinet;
584 
585 	if (!newsk)
586 		goto out;
587 
588 	sock_init_data(NULL, newsk);
589 
590 	sctp_copy_sock(newsk, sk, asoc);
591 	sock_reset_flag(newsk, SOCK_ZAPPED);
592 
593 	newinet = inet_sk(newsk);
594 
595 	newinet->inet_daddr = asoc->peer.primary_addr.v4.sin_addr.s_addr;
596 
597 	sk_refcnt_debug_inc(newsk);
598 
599 	if (newsk->sk_prot->init(newsk)) {
600 		sk_common_release(newsk);
601 		newsk = NULL;
602 	}
603 
604 out:
605 	return newsk;
606 }
607 
608 static int sctp_v4_addr_to_user(struct sctp_sock *sp, union sctp_addr *addr)
609 {
610 	/* No address mapping for V4 sockets */
611 	return sizeof(struct sockaddr_in);
612 }
613 
614 /* Dump the v4 addr to the seq file. */
615 static void sctp_v4_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
616 {
617 	seq_printf(seq, "%pI4 ", &addr->v4.sin_addr);
618 }
619 
620 static void sctp_v4_ecn_capable(struct sock *sk)
621 {
622 	INET_ECN_xmit(sk);
623 }
624 
625 static void sctp_addr_wq_timeout_handler(unsigned long arg)
626 {
627 	struct net *net = (struct net *)arg;
628 	struct sctp_sockaddr_entry *addrw, *temp;
629 	struct sctp_sock *sp;
630 
631 	spin_lock_bh(&net->sctp.addr_wq_lock);
632 
633 	list_for_each_entry_safe(addrw, temp, &net->sctp.addr_waitq, list) {
634 		pr_debug("%s: the first ent in wq:%p is addr:%pISc for cmd:%d at "
635 			 "entry:%p\n", __func__, &net->sctp.addr_waitq, &addrw->a.sa,
636 			 addrw->state, addrw);
637 
638 #if IS_ENABLED(CONFIG_IPV6)
639 		/* Now we send an ASCONF for each association */
640 		/* Note. we currently don't handle link local IPv6 addressees */
641 		if (addrw->a.sa.sa_family == AF_INET6) {
642 			struct in6_addr *in6;
643 
644 			if (ipv6_addr_type(&addrw->a.v6.sin6_addr) &
645 			    IPV6_ADDR_LINKLOCAL)
646 				goto free_next;
647 
648 			in6 = (struct in6_addr *)&addrw->a.v6.sin6_addr;
649 			if (ipv6_chk_addr(net, in6, NULL, 0) == 0 &&
650 			    addrw->state == SCTP_ADDR_NEW) {
651 				unsigned long timeo_val;
652 
653 				pr_debug("%s: this is on DAD, trying %d sec "
654 					 "later\n", __func__,
655 					 SCTP_ADDRESS_TICK_DELAY);
656 
657 				timeo_val = jiffies;
658 				timeo_val += msecs_to_jiffies(SCTP_ADDRESS_TICK_DELAY);
659 				mod_timer(&net->sctp.addr_wq_timer, timeo_val);
660 				break;
661 			}
662 		}
663 #endif
664 		list_for_each_entry(sp, &net->sctp.auto_asconf_splist, auto_asconf_list) {
665 			struct sock *sk;
666 
667 			sk = sctp_opt2sk(sp);
668 			/* ignore bound-specific endpoints */
669 			if (!sctp_is_ep_boundall(sk))
670 				continue;
671 			bh_lock_sock(sk);
672 			if (sctp_asconf_mgmt(sp, addrw) < 0)
673 				pr_debug("%s: sctp_asconf_mgmt failed\n", __func__);
674 			bh_unlock_sock(sk);
675 		}
676 #if IS_ENABLED(CONFIG_IPV6)
677 free_next:
678 #endif
679 		list_del(&addrw->list);
680 		kfree(addrw);
681 	}
682 	spin_unlock_bh(&net->sctp.addr_wq_lock);
683 }
684 
685 static void sctp_free_addr_wq(struct net *net)
686 {
687 	struct sctp_sockaddr_entry *addrw;
688 	struct sctp_sockaddr_entry *temp;
689 
690 	spin_lock_bh(&net->sctp.addr_wq_lock);
691 	del_timer(&net->sctp.addr_wq_timer);
692 	list_for_each_entry_safe(addrw, temp, &net->sctp.addr_waitq, list) {
693 		list_del(&addrw->list);
694 		kfree(addrw);
695 	}
696 	spin_unlock_bh(&net->sctp.addr_wq_lock);
697 }
698 
699 /* lookup the entry for the same address in the addr_waitq
700  * sctp_addr_wq MUST be locked
701  */
702 static struct sctp_sockaddr_entry *sctp_addr_wq_lookup(struct net *net,
703 					struct sctp_sockaddr_entry *addr)
704 {
705 	struct sctp_sockaddr_entry *addrw;
706 
707 	list_for_each_entry(addrw, &net->sctp.addr_waitq, list) {
708 		if (addrw->a.sa.sa_family != addr->a.sa.sa_family)
709 			continue;
710 		if (addrw->a.sa.sa_family == AF_INET) {
711 			if (addrw->a.v4.sin_addr.s_addr ==
712 			    addr->a.v4.sin_addr.s_addr)
713 				return addrw;
714 		} else if (addrw->a.sa.sa_family == AF_INET6) {
715 			if (ipv6_addr_equal(&addrw->a.v6.sin6_addr,
716 			    &addr->a.v6.sin6_addr))
717 				return addrw;
718 		}
719 	}
720 	return NULL;
721 }
722 
723 void sctp_addr_wq_mgmt(struct net *net, struct sctp_sockaddr_entry *addr, int cmd)
724 {
725 	struct sctp_sockaddr_entry *addrw;
726 	unsigned long timeo_val;
727 
728 	/* first, we check if an opposite message already exist in the queue.
729 	 * If we found such message, it is removed.
730 	 * This operation is a bit stupid, but the DHCP client attaches the
731 	 * new address after a couple of addition and deletion of that address
732 	 */
733 
734 	spin_lock_bh(&net->sctp.addr_wq_lock);
735 	/* Offsets existing events in addr_wq */
736 	addrw = sctp_addr_wq_lookup(net, addr);
737 	if (addrw) {
738 		if (addrw->state != cmd) {
739 			pr_debug("%s: offsets existing entry for %d, addr:%pISc "
740 				 "in wq:%p\n", __func__, addrw->state, &addrw->a.sa,
741 				 &net->sctp.addr_waitq);
742 
743 			list_del(&addrw->list);
744 			kfree(addrw);
745 		}
746 		spin_unlock_bh(&net->sctp.addr_wq_lock);
747 		return;
748 	}
749 
750 	/* OK, we have to add the new address to the wait queue */
751 	addrw = kmemdup(addr, sizeof(struct sctp_sockaddr_entry), GFP_ATOMIC);
752 	if (addrw == NULL) {
753 		spin_unlock_bh(&net->sctp.addr_wq_lock);
754 		return;
755 	}
756 	addrw->state = cmd;
757 	list_add_tail(&addrw->list, &net->sctp.addr_waitq);
758 
759 	pr_debug("%s: add new entry for cmd:%d, addr:%pISc in wq:%p\n",
760 		 __func__, addrw->state, &addrw->a.sa, &net->sctp.addr_waitq);
761 
762 	if (!timer_pending(&net->sctp.addr_wq_timer)) {
763 		timeo_val = jiffies;
764 		timeo_val += msecs_to_jiffies(SCTP_ADDRESS_TICK_DELAY);
765 		mod_timer(&net->sctp.addr_wq_timer, timeo_val);
766 	}
767 	spin_unlock_bh(&net->sctp.addr_wq_lock);
768 }
769 
770 /* Event handler for inet address addition/deletion events.
771  * The sctp_local_addr_list needs to be protocted by a spin lock since
772  * multiple notifiers (say IPv4 and IPv6) may be running at the same
773  * time and thus corrupt the list.
774  * The reader side is protected with RCU.
775  */
776 static int sctp_inetaddr_event(struct notifier_block *this, unsigned long ev,
777 			       void *ptr)
778 {
779 	struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
780 	struct sctp_sockaddr_entry *addr = NULL;
781 	struct sctp_sockaddr_entry *temp;
782 	struct net *net = dev_net(ifa->ifa_dev->dev);
783 	int found = 0;
784 
785 	switch (ev) {
786 	case NETDEV_UP:
787 		addr = kmalloc(sizeof(struct sctp_sockaddr_entry), GFP_ATOMIC);
788 		if (addr) {
789 			addr->a.v4.sin_family = AF_INET;
790 			addr->a.v4.sin_port = 0;
791 			addr->a.v4.sin_addr.s_addr = ifa->ifa_local;
792 			addr->valid = 1;
793 			spin_lock_bh(&net->sctp.local_addr_lock);
794 			list_add_tail_rcu(&addr->list, &net->sctp.local_addr_list);
795 			sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_NEW);
796 			spin_unlock_bh(&net->sctp.local_addr_lock);
797 		}
798 		break;
799 	case NETDEV_DOWN:
800 		spin_lock_bh(&net->sctp.local_addr_lock);
801 		list_for_each_entry_safe(addr, temp,
802 					&net->sctp.local_addr_list, list) {
803 			if (addr->a.sa.sa_family == AF_INET &&
804 					addr->a.v4.sin_addr.s_addr ==
805 					ifa->ifa_local) {
806 				sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_DEL);
807 				found = 1;
808 				addr->valid = 0;
809 				list_del_rcu(&addr->list);
810 				break;
811 			}
812 		}
813 		spin_unlock_bh(&net->sctp.local_addr_lock);
814 		if (found)
815 			kfree_rcu(addr, rcu);
816 		break;
817 	}
818 
819 	return NOTIFY_DONE;
820 }
821 
822 /*
823  * Initialize the control inode/socket with a control endpoint data
824  * structure.  This endpoint is reserved exclusively for the OOTB processing.
825  */
826 static int sctp_ctl_sock_init(struct net *net)
827 {
828 	int err;
829 	sa_family_t family = PF_INET;
830 
831 	if (sctp_get_pf_specific(PF_INET6))
832 		family = PF_INET6;
833 
834 	err = inet_ctl_sock_create(&net->sctp.ctl_sock, family,
835 				   SOCK_SEQPACKET, IPPROTO_SCTP, net);
836 
837 	/* If IPv6 socket could not be created, try the IPv4 socket */
838 	if (err < 0 && family == PF_INET6)
839 		err = inet_ctl_sock_create(&net->sctp.ctl_sock, AF_INET,
840 					   SOCK_SEQPACKET, IPPROTO_SCTP,
841 					   net);
842 
843 	if (err < 0) {
844 		pr_err("Failed to create the SCTP control socket\n");
845 		return err;
846 	}
847 	return 0;
848 }
849 
850 /* Register address family specific functions. */
851 int sctp_register_af(struct sctp_af *af)
852 {
853 	switch (af->sa_family) {
854 	case AF_INET:
855 		if (sctp_af_v4_specific)
856 			return 0;
857 		sctp_af_v4_specific = af;
858 		break;
859 	case AF_INET6:
860 		if (sctp_af_v6_specific)
861 			return 0;
862 		sctp_af_v6_specific = af;
863 		break;
864 	default:
865 		return 0;
866 	}
867 
868 	INIT_LIST_HEAD(&af->list);
869 	list_add_tail(&af->list, &sctp_address_families);
870 	return 1;
871 }
872 
873 /* Get the table of functions for manipulating a particular address
874  * family.
875  */
876 struct sctp_af *sctp_get_af_specific(sa_family_t family)
877 {
878 	switch (family) {
879 	case AF_INET:
880 		return sctp_af_v4_specific;
881 	case AF_INET6:
882 		return sctp_af_v6_specific;
883 	default:
884 		return NULL;
885 	}
886 }
887 
888 /* Common code to initialize a AF_INET msg_name. */
889 static void sctp_inet_msgname(char *msgname, int *addr_len)
890 {
891 	struct sockaddr_in *sin;
892 
893 	sin = (struct sockaddr_in *)msgname;
894 	*addr_len = sizeof(struct sockaddr_in);
895 	sin->sin_family = AF_INET;
896 	memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
897 }
898 
899 /* Copy the primary address of the peer primary address as the msg_name. */
900 static void sctp_inet_event_msgname(struct sctp_ulpevent *event, char *msgname,
901 				    int *addr_len)
902 {
903 	struct sockaddr_in *sin, *sinfrom;
904 
905 	if (msgname) {
906 		struct sctp_association *asoc;
907 
908 		asoc = event->asoc;
909 		sctp_inet_msgname(msgname, addr_len);
910 		sin = (struct sockaddr_in *)msgname;
911 		sinfrom = &asoc->peer.primary_addr.v4;
912 		sin->sin_port = htons(asoc->peer.port);
913 		sin->sin_addr.s_addr = sinfrom->sin_addr.s_addr;
914 	}
915 }
916 
917 /* Initialize and copy out a msgname from an inbound skb. */
918 static void sctp_inet_skb_msgname(struct sk_buff *skb, char *msgname, int *len)
919 {
920 	if (msgname) {
921 		struct sctphdr *sh = sctp_hdr(skb);
922 		struct sockaddr_in *sin = (struct sockaddr_in *)msgname;
923 
924 		sctp_inet_msgname(msgname, len);
925 		sin->sin_port = sh->source;
926 		sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
927 	}
928 }
929 
930 /* Do we support this AF? */
931 static int sctp_inet_af_supported(sa_family_t family, struct sctp_sock *sp)
932 {
933 	/* PF_INET only supports AF_INET addresses. */
934 	return AF_INET == family;
935 }
936 
937 /* Address matching with wildcards allowed. */
938 static int sctp_inet_cmp_addr(const union sctp_addr *addr1,
939 			      const union sctp_addr *addr2,
940 			      struct sctp_sock *opt)
941 {
942 	/* PF_INET only supports AF_INET addresses. */
943 	if (addr1->sa.sa_family != addr2->sa.sa_family)
944 		return 0;
945 	if (htonl(INADDR_ANY) == addr1->v4.sin_addr.s_addr ||
946 	    htonl(INADDR_ANY) == addr2->v4.sin_addr.s_addr)
947 		return 1;
948 	if (addr1->v4.sin_addr.s_addr == addr2->v4.sin_addr.s_addr)
949 		return 1;
950 
951 	return 0;
952 }
953 
954 /* Verify that provided sockaddr looks bindable.  Common verification has
955  * already been taken care of.
956  */
957 static int sctp_inet_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
958 {
959 	return sctp_v4_available(addr, opt);
960 }
961 
962 /* Verify that sockaddr looks sendable.  Common verification has already
963  * been taken care of.
964  */
965 static int sctp_inet_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
966 {
967 	return 1;
968 }
969 
970 /* Fill in Supported Address Type information for INIT and INIT-ACK
971  * chunks.  Returns number of addresses supported.
972  */
973 static int sctp_inet_supported_addrs(const struct sctp_sock *opt,
974 				     __be16 *types)
975 {
976 	types[0] = SCTP_PARAM_IPV4_ADDRESS;
977 	return 1;
978 }
979 
980 /* Wrapper routine that calls the ip transmit routine. */
981 static inline int sctp_v4_xmit(struct sk_buff *skb,
982 			       struct sctp_transport *transport)
983 {
984 	struct inet_sock *inet = inet_sk(skb->sk);
985 
986 	pr_debug("%s: skb:%p, len:%d, src:%pI4, dst:%pI4\n", __func__, skb,
987 		 skb->len, &transport->fl.u.ip4.saddr, &transport->fl.u.ip4.daddr);
988 
989 	inet->pmtudisc = transport->param_flags & SPP_PMTUD_ENABLE ?
990 			 IP_PMTUDISC_DO : IP_PMTUDISC_DONT;
991 
992 	SCTP_INC_STATS(sock_net(&inet->sk), SCTP_MIB_OUTSCTPPACKS);
993 
994 	return ip_queue_xmit(&inet->sk, skb, &transport->fl);
995 }
996 
997 static struct sctp_af sctp_af_inet;
998 
999 static struct sctp_pf sctp_pf_inet = {
1000 	.event_msgname = sctp_inet_event_msgname,
1001 	.skb_msgname   = sctp_inet_skb_msgname,
1002 	.af_supported  = sctp_inet_af_supported,
1003 	.cmp_addr      = sctp_inet_cmp_addr,
1004 	.bind_verify   = sctp_inet_bind_verify,
1005 	.send_verify   = sctp_inet_send_verify,
1006 	.supported_addrs = sctp_inet_supported_addrs,
1007 	.create_accept_sk = sctp_v4_create_accept_sk,
1008 	.addr_to_user  = sctp_v4_addr_to_user,
1009 	.to_sk_saddr   = sctp_v4_to_sk_saddr,
1010 	.to_sk_daddr   = sctp_v4_to_sk_daddr,
1011 	.af            = &sctp_af_inet
1012 };
1013 
1014 /* Notifier for inetaddr addition/deletion events.  */
1015 static struct notifier_block sctp_inetaddr_notifier = {
1016 	.notifier_call = sctp_inetaddr_event,
1017 };
1018 
1019 /* Socket operations.  */
1020 static const struct proto_ops inet_seqpacket_ops = {
1021 	.family		   = PF_INET,
1022 	.owner		   = THIS_MODULE,
1023 	.release	   = inet_release,	/* Needs to be wrapped... */
1024 	.bind		   = inet_bind,
1025 	.connect	   = inet_dgram_connect,
1026 	.socketpair	   = sock_no_socketpair,
1027 	.accept		   = inet_accept,
1028 	.getname	   = inet_getname,	/* Semantics are different.  */
1029 	.poll		   = sctp_poll,
1030 	.ioctl		   = inet_ioctl,
1031 	.listen		   = sctp_inet_listen,
1032 	.shutdown	   = inet_shutdown,	/* Looks harmless.  */
1033 	.setsockopt	   = sock_common_setsockopt, /* IP_SOL IP_OPTION is a problem */
1034 	.getsockopt	   = sock_common_getsockopt,
1035 	.sendmsg	   = inet_sendmsg,
1036 	.recvmsg	   = inet_recvmsg,
1037 	.mmap		   = sock_no_mmap,
1038 	.sendpage	   = sock_no_sendpage,
1039 #ifdef CONFIG_COMPAT
1040 	.compat_setsockopt = compat_sock_common_setsockopt,
1041 	.compat_getsockopt = compat_sock_common_getsockopt,
1042 #endif
1043 };
1044 
1045 /* Registration with AF_INET family.  */
1046 static struct inet_protosw sctp_seqpacket_protosw = {
1047 	.type       = SOCK_SEQPACKET,
1048 	.protocol   = IPPROTO_SCTP,
1049 	.prot       = &sctp_prot,
1050 	.ops        = &inet_seqpacket_ops,
1051 	.flags      = SCTP_PROTOSW_FLAG
1052 };
1053 static struct inet_protosw sctp_stream_protosw = {
1054 	.type       = SOCK_STREAM,
1055 	.protocol   = IPPROTO_SCTP,
1056 	.prot       = &sctp_prot,
1057 	.ops        = &inet_seqpacket_ops,
1058 	.flags      = SCTP_PROTOSW_FLAG
1059 };
1060 
1061 /* Register with IP layer.  */
1062 static const struct net_protocol sctp_protocol = {
1063 	.handler     = sctp_rcv,
1064 	.err_handler = sctp_v4_err,
1065 	.no_policy   = 1,
1066 	.netns_ok    = 1,
1067 	.icmp_strict_tag_validation = 1,
1068 };
1069 
1070 /* IPv4 address related functions.  */
1071 static struct sctp_af sctp_af_inet = {
1072 	.sa_family	   = AF_INET,
1073 	.sctp_xmit	   = sctp_v4_xmit,
1074 	.setsockopt	   = ip_setsockopt,
1075 	.getsockopt	   = ip_getsockopt,
1076 	.get_dst	   = sctp_v4_get_dst,
1077 	.get_saddr	   = sctp_v4_get_saddr,
1078 	.copy_addrlist	   = sctp_v4_copy_addrlist,
1079 	.from_skb	   = sctp_v4_from_skb,
1080 	.from_sk	   = sctp_v4_from_sk,
1081 	.from_addr_param   = sctp_v4_from_addr_param,
1082 	.to_addr_param	   = sctp_v4_to_addr_param,
1083 	.cmp_addr	   = sctp_v4_cmp_addr,
1084 	.addr_valid	   = sctp_v4_addr_valid,
1085 	.inaddr_any	   = sctp_v4_inaddr_any,
1086 	.is_any		   = sctp_v4_is_any,
1087 	.available	   = sctp_v4_available,
1088 	.scope		   = sctp_v4_scope,
1089 	.skb_iif	   = sctp_v4_skb_iif,
1090 	.is_ce		   = sctp_v4_is_ce,
1091 	.seq_dump_addr	   = sctp_v4_seq_dump_addr,
1092 	.ecn_capable	   = sctp_v4_ecn_capable,
1093 	.net_header_len	   = sizeof(struct iphdr),
1094 	.sockaddr_len	   = sizeof(struct sockaddr_in),
1095 #ifdef CONFIG_COMPAT
1096 	.compat_setsockopt = compat_ip_setsockopt,
1097 	.compat_getsockopt = compat_ip_getsockopt,
1098 #endif
1099 };
1100 
1101 struct sctp_pf *sctp_get_pf_specific(sa_family_t family)
1102 {
1103 	switch (family) {
1104 	case PF_INET:
1105 		return sctp_pf_inet_specific;
1106 	case PF_INET6:
1107 		return sctp_pf_inet6_specific;
1108 	default:
1109 		return NULL;
1110 	}
1111 }
1112 
1113 /* Register the PF specific function table.  */
1114 int sctp_register_pf(struct sctp_pf *pf, sa_family_t family)
1115 {
1116 	switch (family) {
1117 	case PF_INET:
1118 		if (sctp_pf_inet_specific)
1119 			return 0;
1120 		sctp_pf_inet_specific = pf;
1121 		break;
1122 	case PF_INET6:
1123 		if (sctp_pf_inet6_specific)
1124 			return 0;
1125 		sctp_pf_inet6_specific = pf;
1126 		break;
1127 	default:
1128 		return 0;
1129 	}
1130 	return 1;
1131 }
1132 
1133 static inline int init_sctp_mibs(struct net *net)
1134 {
1135 	net->sctp.sctp_statistics = alloc_percpu(struct sctp_mib);
1136 	if (!net->sctp.sctp_statistics)
1137 		return -ENOMEM;
1138 	return 0;
1139 }
1140 
1141 static inline void cleanup_sctp_mibs(struct net *net)
1142 {
1143 	free_percpu(net->sctp.sctp_statistics);
1144 }
1145 
1146 static void sctp_v4_pf_init(void)
1147 {
1148 	/* Initialize the SCTP specific PF functions. */
1149 	sctp_register_pf(&sctp_pf_inet, PF_INET);
1150 	sctp_register_af(&sctp_af_inet);
1151 }
1152 
1153 static void sctp_v4_pf_exit(void)
1154 {
1155 	list_del(&sctp_af_inet.list);
1156 }
1157 
1158 static int sctp_v4_protosw_init(void)
1159 {
1160 	int rc;
1161 
1162 	rc = proto_register(&sctp_prot, 1);
1163 	if (rc)
1164 		return rc;
1165 
1166 	/* Register SCTP(UDP and TCP style) with socket layer.  */
1167 	inet_register_protosw(&sctp_seqpacket_protosw);
1168 	inet_register_protosw(&sctp_stream_protosw);
1169 
1170 	return 0;
1171 }
1172 
1173 static void sctp_v4_protosw_exit(void)
1174 {
1175 	inet_unregister_protosw(&sctp_stream_protosw);
1176 	inet_unregister_protosw(&sctp_seqpacket_protosw);
1177 	proto_unregister(&sctp_prot);
1178 }
1179 
1180 static int sctp_v4_add_protocol(void)
1181 {
1182 	/* Register notifier for inet address additions/deletions. */
1183 	register_inetaddr_notifier(&sctp_inetaddr_notifier);
1184 
1185 	/* Register SCTP with inet layer.  */
1186 	if (inet_add_protocol(&sctp_protocol, IPPROTO_SCTP) < 0)
1187 		return -EAGAIN;
1188 
1189 	return 0;
1190 }
1191 
1192 static void sctp_v4_del_protocol(void)
1193 {
1194 	inet_del_protocol(&sctp_protocol, IPPROTO_SCTP);
1195 	unregister_inetaddr_notifier(&sctp_inetaddr_notifier);
1196 }
1197 
1198 static int __net_init sctp_defaults_init(struct net *net)
1199 {
1200 	int status;
1201 
1202 	/*
1203 	 * 14. Suggested SCTP Protocol Parameter Values
1204 	 */
1205 	/* The following protocol parameters are RECOMMENDED:  */
1206 	/* RTO.Initial              - 3  seconds */
1207 	net->sctp.rto_initial			= SCTP_RTO_INITIAL;
1208 	/* RTO.Min                  - 1  second */
1209 	net->sctp.rto_min	 		= SCTP_RTO_MIN;
1210 	/* RTO.Max                 -  60 seconds */
1211 	net->sctp.rto_max 			= SCTP_RTO_MAX;
1212 	/* RTO.Alpha                - 1/8 */
1213 	net->sctp.rto_alpha			= SCTP_RTO_ALPHA;
1214 	/* RTO.Beta                 - 1/4 */
1215 	net->sctp.rto_beta			= SCTP_RTO_BETA;
1216 
1217 	/* Valid.Cookie.Life        - 60  seconds */
1218 	net->sctp.valid_cookie_life		= SCTP_DEFAULT_COOKIE_LIFE;
1219 
1220 	/* Whether Cookie Preservative is enabled(1) or not(0) */
1221 	net->sctp.cookie_preserve_enable 	= 1;
1222 
1223 	/* Default sctp sockets to use md5 as their hmac alg */
1224 #if defined (CONFIG_SCTP_DEFAULT_COOKIE_HMAC_MD5)
1225 	net->sctp.sctp_hmac_alg			= "md5";
1226 #elif defined (CONFIG_SCTP_DEFAULT_COOKIE_HMAC_SHA1)
1227 	net->sctp.sctp_hmac_alg			= "sha1";
1228 #else
1229 	net->sctp.sctp_hmac_alg			= NULL;
1230 #endif
1231 
1232 	/* Max.Burst		    - 4 */
1233 	net->sctp.max_burst			= SCTP_DEFAULT_MAX_BURST;
1234 
1235 	/* Enable pf state by default */
1236 	net->sctp.pf_enable = 1;
1237 
1238 	/* Association.Max.Retrans  - 10 attempts
1239 	 * Path.Max.Retrans         - 5  attempts (per destination address)
1240 	 * Max.Init.Retransmits     - 8  attempts
1241 	 */
1242 	net->sctp.max_retrans_association	= 10;
1243 	net->sctp.max_retrans_path		= 5;
1244 	net->sctp.max_retrans_init		= 8;
1245 
1246 	/* Sendbuffer growth	    - do per-socket accounting */
1247 	net->sctp.sndbuf_policy			= 0;
1248 
1249 	/* Rcvbuffer growth	    - do per-socket accounting */
1250 	net->sctp.rcvbuf_policy			= 0;
1251 
1252 	/* HB.interval              - 30 seconds */
1253 	net->sctp.hb_interval			= SCTP_DEFAULT_TIMEOUT_HEARTBEAT;
1254 
1255 	/* delayed SACK timeout */
1256 	net->sctp.sack_timeout			= SCTP_DEFAULT_TIMEOUT_SACK;
1257 
1258 	/* Disable ADDIP by default. */
1259 	net->sctp.addip_enable = 0;
1260 	net->sctp.addip_noauth = 0;
1261 	net->sctp.default_auto_asconf = 0;
1262 
1263 	/* Enable PR-SCTP by default. */
1264 	net->sctp.prsctp_enable = 1;
1265 
1266 	/* Disable RECONF by default. */
1267 	net->sctp.reconf_enable = 0;
1268 
1269 	/* Disable AUTH by default. */
1270 	net->sctp.auth_enable = 0;
1271 
1272 	/* Set SCOPE policy to enabled */
1273 	net->sctp.scope_policy = SCTP_SCOPE_POLICY_ENABLE;
1274 
1275 	/* Set the default rwnd update threshold */
1276 	net->sctp.rwnd_upd_shift = SCTP_DEFAULT_RWND_SHIFT;
1277 
1278 	/* Initialize maximum autoclose timeout. */
1279 	net->sctp.max_autoclose		= INT_MAX / HZ;
1280 
1281 	status = sctp_sysctl_net_register(net);
1282 	if (status)
1283 		goto err_sysctl_register;
1284 
1285 	/* Allocate and initialise sctp mibs.  */
1286 	status = init_sctp_mibs(net);
1287 	if (status)
1288 		goto err_init_mibs;
1289 
1290 	/* Initialize proc fs directory.  */
1291 	status = sctp_proc_init(net);
1292 	if (status)
1293 		goto err_init_proc;
1294 
1295 	sctp_dbg_objcnt_init(net);
1296 
1297 	/* Initialize the local address list. */
1298 	INIT_LIST_HEAD(&net->sctp.local_addr_list);
1299 	spin_lock_init(&net->sctp.local_addr_lock);
1300 	sctp_get_local_addr_list(net);
1301 
1302 	/* Initialize the address event list */
1303 	INIT_LIST_HEAD(&net->sctp.addr_waitq);
1304 	INIT_LIST_HEAD(&net->sctp.auto_asconf_splist);
1305 	spin_lock_init(&net->sctp.addr_wq_lock);
1306 	net->sctp.addr_wq_timer.expires = 0;
1307 	setup_timer(&net->sctp.addr_wq_timer, sctp_addr_wq_timeout_handler,
1308 		    (unsigned long)net);
1309 
1310 	return 0;
1311 
1312 err_init_proc:
1313 	cleanup_sctp_mibs(net);
1314 err_init_mibs:
1315 	sctp_sysctl_net_unregister(net);
1316 err_sysctl_register:
1317 	return status;
1318 }
1319 
1320 static void __net_exit sctp_defaults_exit(struct net *net)
1321 {
1322 	/* Free the local address list */
1323 	sctp_free_addr_wq(net);
1324 	sctp_free_local_addr_list(net);
1325 
1326 	sctp_dbg_objcnt_exit(net);
1327 
1328 	sctp_proc_exit(net);
1329 	cleanup_sctp_mibs(net);
1330 	sctp_sysctl_net_unregister(net);
1331 }
1332 
1333 static struct pernet_operations sctp_defaults_ops = {
1334 	.init = sctp_defaults_init,
1335 	.exit = sctp_defaults_exit,
1336 };
1337 
1338 static int __net_init sctp_ctrlsock_init(struct net *net)
1339 {
1340 	int status;
1341 
1342 	/* Initialize the control inode/socket for handling OOTB packets.  */
1343 	status = sctp_ctl_sock_init(net);
1344 	if (status)
1345 		pr_err("Failed to initialize the SCTP control sock\n");
1346 
1347 	return status;
1348 }
1349 
1350 static void __net_init sctp_ctrlsock_exit(struct net *net)
1351 {
1352 	/* Free the control endpoint.  */
1353 	inet_ctl_sock_destroy(net->sctp.ctl_sock);
1354 }
1355 
1356 static struct pernet_operations sctp_ctrlsock_ops = {
1357 	.init = sctp_ctrlsock_init,
1358 	.exit = sctp_ctrlsock_exit,
1359 };
1360 
1361 /* Initialize the universe into something sensible.  */
1362 static __init int sctp_init(void)
1363 {
1364 	int i;
1365 	int status = -EINVAL;
1366 	unsigned long goal;
1367 	unsigned long limit;
1368 	int max_share;
1369 	int order;
1370 	int num_entries;
1371 	int max_entry_order;
1372 
1373 	sock_skb_cb_check_size(sizeof(struct sctp_ulpevent));
1374 
1375 	/* Allocate bind_bucket and chunk caches. */
1376 	status = -ENOBUFS;
1377 	sctp_bucket_cachep = kmem_cache_create("sctp_bind_bucket",
1378 					       sizeof(struct sctp_bind_bucket),
1379 					       0, SLAB_HWCACHE_ALIGN,
1380 					       NULL);
1381 	if (!sctp_bucket_cachep)
1382 		goto out;
1383 
1384 	sctp_chunk_cachep = kmem_cache_create("sctp_chunk",
1385 					       sizeof(struct sctp_chunk),
1386 					       0, SLAB_HWCACHE_ALIGN,
1387 					       NULL);
1388 	if (!sctp_chunk_cachep)
1389 		goto err_chunk_cachep;
1390 
1391 	status = percpu_counter_init(&sctp_sockets_allocated, 0, GFP_KERNEL);
1392 	if (status)
1393 		goto err_percpu_counter_init;
1394 
1395 	/* Implementation specific variables. */
1396 
1397 	/* Initialize default stream count setup information. */
1398 	sctp_max_instreams    		= SCTP_DEFAULT_INSTREAMS;
1399 	sctp_max_outstreams   		= SCTP_DEFAULT_OUTSTREAMS;
1400 
1401 	/* Initialize handle used for association ids. */
1402 	idr_init(&sctp_assocs_id);
1403 
1404 	limit = nr_free_buffer_pages() / 8;
1405 	limit = max(limit, 128UL);
1406 	sysctl_sctp_mem[0] = limit / 4 * 3;
1407 	sysctl_sctp_mem[1] = limit;
1408 	sysctl_sctp_mem[2] = sysctl_sctp_mem[0] * 2;
1409 
1410 	/* Set per-socket limits to no more than 1/128 the pressure threshold*/
1411 	limit = (sysctl_sctp_mem[1]) << (PAGE_SHIFT - 7);
1412 	max_share = min(4UL*1024*1024, limit);
1413 
1414 	sysctl_sctp_rmem[0] = SK_MEM_QUANTUM; /* give each asoc 1 page min */
1415 	sysctl_sctp_rmem[1] = 1500 * SKB_TRUESIZE(1);
1416 	sysctl_sctp_rmem[2] = max(sysctl_sctp_rmem[1], max_share);
1417 
1418 	sysctl_sctp_wmem[0] = SK_MEM_QUANTUM;
1419 	sysctl_sctp_wmem[1] = 16*1024;
1420 	sysctl_sctp_wmem[2] = max(64*1024, max_share);
1421 
1422 	/* Size and allocate the association hash table.
1423 	 * The methodology is similar to that of the tcp hash tables.
1424 	 * Though not identical.  Start by getting a goal size
1425 	 */
1426 	if (totalram_pages >= (128 * 1024))
1427 		goal = totalram_pages >> (22 - PAGE_SHIFT);
1428 	else
1429 		goal = totalram_pages >> (24 - PAGE_SHIFT);
1430 
1431 	/* Then compute the page order for said goal */
1432 	order = get_order(goal);
1433 
1434 	/* Now compute the required page order for the maximum sized table we
1435 	 * want to create
1436 	 */
1437 	max_entry_order = get_order(MAX_SCTP_PORT_HASH_ENTRIES *
1438 				    sizeof(struct sctp_bind_hashbucket));
1439 
1440 	/* Limit the page order by that maximum hash table size */
1441 	order = min(order, max_entry_order);
1442 
1443 	/* Allocate and initialize the endpoint hash table.  */
1444 	sctp_ep_hashsize = 64;
1445 	sctp_ep_hashtable =
1446 		kmalloc(64 * sizeof(struct sctp_hashbucket), GFP_KERNEL);
1447 	if (!sctp_ep_hashtable) {
1448 		pr_err("Failed endpoint_hash alloc\n");
1449 		status = -ENOMEM;
1450 		goto err_ehash_alloc;
1451 	}
1452 	for (i = 0; i < sctp_ep_hashsize; i++) {
1453 		rwlock_init(&sctp_ep_hashtable[i].lock);
1454 		INIT_HLIST_HEAD(&sctp_ep_hashtable[i].chain);
1455 	}
1456 
1457 	/* Allocate and initialize the SCTP port hash table.
1458 	 * Note that order is initalized to start at the max sized
1459 	 * table we want to support.  If we can't get that many pages
1460 	 * reduce the order and try again
1461 	 */
1462 	do {
1463 		sctp_port_hashtable = (struct sctp_bind_hashbucket *)
1464 			__get_free_pages(GFP_KERNEL | __GFP_NOWARN, order);
1465 	} while (!sctp_port_hashtable && --order > 0);
1466 
1467 	if (!sctp_port_hashtable) {
1468 		pr_err("Failed bind hash alloc\n");
1469 		status = -ENOMEM;
1470 		goto err_bhash_alloc;
1471 	}
1472 
1473 	/* Now compute the number of entries that will fit in the
1474 	 * port hash space we allocated
1475 	 */
1476 	num_entries = (1UL << order) * PAGE_SIZE /
1477 		      sizeof(struct sctp_bind_hashbucket);
1478 
1479 	/* And finish by rounding it down to the nearest power of two
1480 	 * this wastes some memory of course, but its needed because
1481 	 * the hash function operates based on the assumption that
1482 	 * that the number of entries is a power of two
1483 	 */
1484 	sctp_port_hashsize = rounddown_pow_of_two(num_entries);
1485 
1486 	for (i = 0; i < sctp_port_hashsize; i++) {
1487 		spin_lock_init(&sctp_port_hashtable[i].lock);
1488 		INIT_HLIST_HEAD(&sctp_port_hashtable[i].chain);
1489 	}
1490 
1491 	status = sctp_transport_hashtable_init();
1492 	if (status)
1493 		goto err_thash_alloc;
1494 
1495 	pr_info("Hash tables configured (bind %d/%d)\n", sctp_port_hashsize,
1496 		num_entries);
1497 
1498 	sctp_sysctl_register();
1499 
1500 	INIT_LIST_HEAD(&sctp_address_families);
1501 	sctp_v4_pf_init();
1502 	sctp_v6_pf_init();
1503 
1504 	status = register_pernet_subsys(&sctp_defaults_ops);
1505 	if (status)
1506 		goto err_register_defaults;
1507 
1508 	status = sctp_v4_protosw_init();
1509 	if (status)
1510 		goto err_protosw_init;
1511 
1512 	status = sctp_v6_protosw_init();
1513 	if (status)
1514 		goto err_v6_protosw_init;
1515 
1516 	status = register_pernet_subsys(&sctp_ctrlsock_ops);
1517 	if (status)
1518 		goto err_register_ctrlsock;
1519 
1520 	status = sctp_v4_add_protocol();
1521 	if (status)
1522 		goto err_add_protocol;
1523 
1524 	/* Register SCTP with inet6 layer.  */
1525 	status = sctp_v6_add_protocol();
1526 	if (status)
1527 		goto err_v6_add_protocol;
1528 
1529 	if (sctp_offload_init() < 0)
1530 		pr_crit("%s: Cannot add SCTP protocol offload\n", __func__);
1531 
1532 out:
1533 	return status;
1534 err_v6_add_protocol:
1535 	sctp_v4_del_protocol();
1536 err_add_protocol:
1537 	unregister_pernet_subsys(&sctp_ctrlsock_ops);
1538 err_register_ctrlsock:
1539 	sctp_v6_protosw_exit();
1540 err_v6_protosw_init:
1541 	sctp_v4_protosw_exit();
1542 err_protosw_init:
1543 	unregister_pernet_subsys(&sctp_defaults_ops);
1544 err_register_defaults:
1545 	sctp_v4_pf_exit();
1546 	sctp_v6_pf_exit();
1547 	sctp_sysctl_unregister();
1548 	free_pages((unsigned long)sctp_port_hashtable,
1549 		   get_order(sctp_port_hashsize *
1550 			     sizeof(struct sctp_bind_hashbucket)));
1551 err_bhash_alloc:
1552 	sctp_transport_hashtable_destroy();
1553 err_thash_alloc:
1554 	kfree(sctp_ep_hashtable);
1555 err_ehash_alloc:
1556 	percpu_counter_destroy(&sctp_sockets_allocated);
1557 err_percpu_counter_init:
1558 	kmem_cache_destroy(sctp_chunk_cachep);
1559 err_chunk_cachep:
1560 	kmem_cache_destroy(sctp_bucket_cachep);
1561 	goto out;
1562 }
1563 
1564 /* Exit handler for the SCTP protocol.  */
1565 static __exit void sctp_exit(void)
1566 {
1567 	/* BUG.  This should probably do something useful like clean
1568 	 * up all the remaining associations and all that memory.
1569 	 */
1570 
1571 	/* Unregister with inet6/inet layers. */
1572 	sctp_v6_del_protocol();
1573 	sctp_v4_del_protocol();
1574 
1575 	unregister_pernet_subsys(&sctp_ctrlsock_ops);
1576 
1577 	/* Free protosw registrations */
1578 	sctp_v6_protosw_exit();
1579 	sctp_v4_protosw_exit();
1580 
1581 	unregister_pernet_subsys(&sctp_defaults_ops);
1582 
1583 	/* Unregister with socket layer. */
1584 	sctp_v6_pf_exit();
1585 	sctp_v4_pf_exit();
1586 
1587 	sctp_sysctl_unregister();
1588 
1589 	free_pages((unsigned long)sctp_port_hashtable,
1590 		   get_order(sctp_port_hashsize *
1591 			     sizeof(struct sctp_bind_hashbucket)));
1592 	kfree(sctp_ep_hashtable);
1593 	sctp_transport_hashtable_destroy();
1594 
1595 	percpu_counter_destroy(&sctp_sockets_allocated);
1596 
1597 	rcu_barrier(); /* Wait for completion of call_rcu()'s */
1598 
1599 	kmem_cache_destroy(sctp_chunk_cachep);
1600 	kmem_cache_destroy(sctp_bucket_cachep);
1601 }
1602 
1603 module_init(sctp_init);
1604 module_exit(sctp_exit);
1605 
1606 /*
1607  * __stringify doesn't likes enums, so use IPPROTO_SCTP value (132) directly.
1608  */
1609 MODULE_ALIAS("net-pf-" __stringify(PF_INET) "-proto-132");
1610 MODULE_ALIAS("net-pf-" __stringify(PF_INET6) "-proto-132");
1611 MODULE_AUTHOR("Linux Kernel SCTP developers <linux-sctp@vger.kernel.org>");
1612 MODULE_DESCRIPTION("Support for the SCTP protocol (RFC2960)");
1613 module_param_named(no_checksums, sctp_checksum_disable, bool, 0644);
1614 MODULE_PARM_DESC(no_checksums, "Disable checksums computing and verification");
1615 MODULE_LICENSE("GPL");
1616