xref: /openbmc/linux/net/sctp/protocol.c (revision faa16bc4)
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 /* Private helper to extract ipv4 address and stash them in
84  * the protocol structure.
85  */
86 static void sctp_v4_copy_addrlist(struct list_head *addrlist,
87 				  struct net_device *dev)
88 {
89 	struct in_device *in_dev;
90 	struct in_ifaddr *ifa;
91 	struct sctp_sockaddr_entry *addr;
92 
93 	rcu_read_lock();
94 	if ((in_dev = __in_dev_get_rcu(dev)) == NULL) {
95 		rcu_read_unlock();
96 		return;
97 	}
98 
99 	for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
100 		/* Add the address to the local list.  */
101 		addr = kzalloc(sizeof(*addr), GFP_ATOMIC);
102 		if (addr) {
103 			addr->a.v4.sin_family = AF_INET;
104 			addr->a.v4.sin_port = 0;
105 			addr->a.v4.sin_addr.s_addr = ifa->ifa_local;
106 			addr->valid = 1;
107 			INIT_LIST_HEAD(&addr->list);
108 			list_add_tail(&addr->list, addrlist);
109 		}
110 	}
111 
112 	rcu_read_unlock();
113 }
114 
115 /* Extract our IP addresses from the system and stash them in the
116  * protocol structure.
117  */
118 static void sctp_get_local_addr_list(struct net *net)
119 {
120 	struct net_device *dev;
121 	struct list_head *pos;
122 	struct sctp_af *af;
123 
124 	rcu_read_lock();
125 	for_each_netdev_rcu(net, dev) {
126 		list_for_each(pos, &sctp_address_families) {
127 			af = list_entry(pos, struct sctp_af, list);
128 			af->copy_addrlist(&net->sctp.local_addr_list, dev);
129 		}
130 	}
131 	rcu_read_unlock();
132 }
133 
134 /* Free the existing local addresses.  */
135 static void sctp_free_local_addr_list(struct net *net)
136 {
137 	struct sctp_sockaddr_entry *addr;
138 	struct list_head *pos, *temp;
139 
140 	list_for_each_safe(pos, temp, &net->sctp.local_addr_list) {
141 		addr = list_entry(pos, struct sctp_sockaddr_entry, list);
142 		list_del(pos);
143 		kfree(addr);
144 	}
145 }
146 
147 /* Copy the local addresses which are valid for 'scope' into 'bp'.  */
148 int sctp_copy_local_addr_list(struct net *net, struct sctp_bind_addr *bp,
149 			      enum sctp_scope scope, gfp_t gfp, int copy_flags)
150 {
151 	struct sctp_sockaddr_entry *addr;
152 	union sctp_addr laddr;
153 	int error = 0;
154 
155 	rcu_read_lock();
156 	list_for_each_entry_rcu(addr, &net->sctp.local_addr_list, list) {
157 		if (!addr->valid)
158 			continue;
159 		if (!sctp_in_scope(net, &addr->a, scope))
160 			continue;
161 
162 		/* Now that the address is in scope, check to see if
163 		 * the address type is really supported by the local
164 		 * sock as well as the remote peer.
165 		 */
166 		if (addr->a.sa.sa_family == AF_INET &&
167 		    !(copy_flags & SCTP_ADDR4_PEERSUPP))
168 			continue;
169 		if (addr->a.sa.sa_family == AF_INET6 &&
170 		    (!(copy_flags & SCTP_ADDR6_ALLOWED) ||
171 		     !(copy_flags & SCTP_ADDR6_PEERSUPP)))
172 			continue;
173 
174 		laddr = addr->a;
175 		/* also works for setting ipv6 address port */
176 		laddr.v4.sin_port = htons(bp->port);
177 		if (sctp_bind_addr_state(bp, &laddr) != -1)
178 			continue;
179 
180 		error = sctp_add_bind_addr(bp, &addr->a, sizeof(addr->a),
181 					   SCTP_ADDR_SRC, GFP_ATOMIC);
182 		if (error)
183 			break;
184 	}
185 
186 	rcu_read_unlock();
187 	return error;
188 }
189 
190 /* Copy over any ip options */
191 static void sctp_v4_copy_ip_options(struct sock *sk, struct sock *newsk)
192 {
193 	struct inet_sock *newinet, *inet = inet_sk(sk);
194 	struct ip_options_rcu *inet_opt, *newopt = NULL;
195 
196 	newinet = inet_sk(newsk);
197 
198 	rcu_read_lock();
199 	inet_opt = rcu_dereference(inet->inet_opt);
200 	if (inet_opt) {
201 		newopt = sock_kmalloc(newsk, sizeof(*inet_opt) +
202 				      inet_opt->opt.optlen, GFP_ATOMIC);
203 		if (newopt)
204 			memcpy(newopt, inet_opt, sizeof(*inet_opt) +
205 			       inet_opt->opt.optlen);
206 		else
207 			pr_err("%s: Failed to copy ip options\n", __func__);
208 	}
209 	RCU_INIT_POINTER(newinet->inet_opt, newopt);
210 	rcu_read_unlock();
211 }
212 
213 /* Account for the IP options */
214 static int sctp_v4_ip_options_len(struct sock *sk)
215 {
216 	struct inet_sock *inet = inet_sk(sk);
217 	struct ip_options_rcu *inet_opt;
218 	int len = 0;
219 
220 	rcu_read_lock();
221 	inet_opt = rcu_dereference(inet->inet_opt);
222 	if (inet_opt)
223 		len = inet_opt->opt.optlen;
224 
225 	rcu_read_unlock();
226 	return len;
227 }
228 
229 /* Initialize a sctp_addr from in incoming skb.  */
230 static void sctp_v4_from_skb(union sctp_addr *addr, struct sk_buff *skb,
231 			     int is_saddr)
232 {
233 	/* Always called on head skb, so this is safe */
234 	struct sctphdr *sh = sctp_hdr(skb);
235 	struct sockaddr_in *sa = &addr->v4;
236 
237 	addr->v4.sin_family = AF_INET;
238 
239 	if (is_saddr) {
240 		sa->sin_port = sh->source;
241 		sa->sin_addr.s_addr = ip_hdr(skb)->saddr;
242 	} else {
243 		sa->sin_port = sh->dest;
244 		sa->sin_addr.s_addr = ip_hdr(skb)->daddr;
245 	}
246 }
247 
248 /* Initialize an sctp_addr from a socket. */
249 static void sctp_v4_from_sk(union sctp_addr *addr, struct sock *sk)
250 {
251 	addr->v4.sin_family = AF_INET;
252 	addr->v4.sin_port = 0;
253 	addr->v4.sin_addr.s_addr = inet_sk(sk)->inet_rcv_saddr;
254 }
255 
256 /* Initialize sk->sk_rcv_saddr from sctp_addr. */
257 static void sctp_v4_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
258 {
259 	inet_sk(sk)->inet_rcv_saddr = addr->v4.sin_addr.s_addr;
260 }
261 
262 /* Initialize sk->sk_daddr from sctp_addr. */
263 static void sctp_v4_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
264 {
265 	inet_sk(sk)->inet_daddr = addr->v4.sin_addr.s_addr;
266 }
267 
268 /* Initialize a sctp_addr from an address parameter. */
269 static void sctp_v4_from_addr_param(union sctp_addr *addr,
270 				    union sctp_addr_param *param,
271 				    __be16 port, int iif)
272 {
273 	addr->v4.sin_family = AF_INET;
274 	addr->v4.sin_port = port;
275 	addr->v4.sin_addr.s_addr = param->v4.addr.s_addr;
276 }
277 
278 /* Initialize an address parameter from a sctp_addr and return the length
279  * of the address parameter.
280  */
281 static int sctp_v4_to_addr_param(const union sctp_addr *addr,
282 				 union sctp_addr_param *param)
283 {
284 	int length = sizeof(struct sctp_ipv4addr_param);
285 
286 	param->v4.param_hdr.type = SCTP_PARAM_IPV4_ADDRESS;
287 	param->v4.param_hdr.length = htons(length);
288 	param->v4.addr.s_addr = addr->v4.sin_addr.s_addr;
289 
290 	return length;
291 }
292 
293 /* Initialize a sctp_addr from a dst_entry. */
294 static void sctp_v4_dst_saddr(union sctp_addr *saddr, struct flowi4 *fl4,
295 			      __be16 port)
296 {
297 	saddr->v4.sin_family = AF_INET;
298 	saddr->v4.sin_port = port;
299 	saddr->v4.sin_addr.s_addr = fl4->saddr;
300 }
301 
302 /* Compare two addresses exactly. */
303 static int sctp_v4_cmp_addr(const union sctp_addr *addr1,
304 			    const union sctp_addr *addr2)
305 {
306 	if (addr1->sa.sa_family != addr2->sa.sa_family)
307 		return 0;
308 	if (addr1->v4.sin_port != addr2->v4.sin_port)
309 		return 0;
310 	if (addr1->v4.sin_addr.s_addr != addr2->v4.sin_addr.s_addr)
311 		return 0;
312 
313 	return 1;
314 }
315 
316 /* Initialize addr struct to INADDR_ANY. */
317 static void sctp_v4_inaddr_any(union sctp_addr *addr, __be16 port)
318 {
319 	addr->v4.sin_family = AF_INET;
320 	addr->v4.sin_addr.s_addr = htonl(INADDR_ANY);
321 	addr->v4.sin_port = port;
322 }
323 
324 /* Is this a wildcard address? */
325 static int sctp_v4_is_any(const union sctp_addr *addr)
326 {
327 	return htonl(INADDR_ANY) == addr->v4.sin_addr.s_addr;
328 }
329 
330 /* This function checks if the address is a valid address to be used for
331  * SCTP binding.
332  *
333  * Output:
334  * Return 0 - If the address is a non-unicast or an illegal address.
335  * Return 1 - If the address is a unicast.
336  */
337 static int sctp_v4_addr_valid(union sctp_addr *addr,
338 			      struct sctp_sock *sp,
339 			      const struct sk_buff *skb)
340 {
341 	/* IPv4 addresses not allowed */
342 	if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
343 		return 0;
344 
345 	/* Is this a non-unicast address or a unusable SCTP address? */
346 	if (IS_IPV4_UNUSABLE_ADDRESS(addr->v4.sin_addr.s_addr))
347 		return 0;
348 
349 	/* Is this a broadcast address? */
350 	if (skb && skb_rtable(skb)->rt_flags & RTCF_BROADCAST)
351 		return 0;
352 
353 	return 1;
354 }
355 
356 /* Should this be available for binding?   */
357 static int sctp_v4_available(union sctp_addr *addr, struct sctp_sock *sp)
358 {
359 	struct net *net = sock_net(&sp->inet.sk);
360 	int ret = inet_addr_type(net, addr->v4.sin_addr.s_addr);
361 
362 
363 	if (addr->v4.sin_addr.s_addr != htonl(INADDR_ANY) &&
364 	   ret != RTN_LOCAL &&
365 	   !sp->inet.freebind &&
366 	   !net->ipv4.sysctl_ip_nonlocal_bind)
367 		return 0;
368 
369 	if (ipv6_only_sock(sctp_opt2sk(sp)))
370 		return 0;
371 
372 	return 1;
373 }
374 
375 /* Checking the loopback, private and other address scopes as defined in
376  * RFC 1918.   The IPv4 scoping is based on the draft for SCTP IPv4
377  * scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>.
378  *
379  * Level 0 - unusable SCTP addresses
380  * Level 1 - loopback address
381  * Level 2 - link-local addresses
382  * Level 3 - private addresses.
383  * Level 4 - global addresses
384  * For INIT and INIT-ACK address list, let L be the level of
385  * of requested destination address, sender and receiver
386  * SHOULD include all of its addresses with level greater
387  * than or equal to L.
388  *
389  * IPv4 scoping can be controlled through sysctl option
390  * net.sctp.addr_scope_policy
391  */
392 static enum sctp_scope sctp_v4_scope(union sctp_addr *addr)
393 {
394 	enum sctp_scope retval;
395 
396 	/* Check for unusable SCTP addresses. */
397 	if (IS_IPV4_UNUSABLE_ADDRESS(addr->v4.sin_addr.s_addr)) {
398 		retval =  SCTP_SCOPE_UNUSABLE;
399 	} else if (ipv4_is_loopback(addr->v4.sin_addr.s_addr)) {
400 		retval = SCTP_SCOPE_LOOPBACK;
401 	} else if (ipv4_is_linklocal_169(addr->v4.sin_addr.s_addr)) {
402 		retval = SCTP_SCOPE_LINK;
403 	} else if (ipv4_is_private_10(addr->v4.sin_addr.s_addr) ||
404 		   ipv4_is_private_172(addr->v4.sin_addr.s_addr) ||
405 		   ipv4_is_private_192(addr->v4.sin_addr.s_addr)) {
406 		retval = SCTP_SCOPE_PRIVATE;
407 	} else {
408 		retval = SCTP_SCOPE_GLOBAL;
409 	}
410 
411 	return retval;
412 }
413 
414 /* Returns a valid dst cache entry for the given source and destination ip
415  * addresses. If an association is passed, trys to get a dst entry with a
416  * source address that matches an address in the bind address list.
417  */
418 static void sctp_v4_get_dst(struct sctp_transport *t, union sctp_addr *saddr,
419 				struct flowi *fl, struct sock *sk)
420 {
421 	struct sctp_association *asoc = t->asoc;
422 	struct rtable *rt;
423 	struct flowi4 *fl4 = &fl->u.ip4;
424 	struct sctp_bind_addr *bp;
425 	struct sctp_sockaddr_entry *laddr;
426 	struct dst_entry *dst = NULL;
427 	union sctp_addr *daddr = &t->ipaddr;
428 	union sctp_addr dst_saddr;
429 
430 	memset(fl4, 0x0, sizeof(struct flowi4));
431 	fl4->daddr  = daddr->v4.sin_addr.s_addr;
432 	fl4->fl4_dport = daddr->v4.sin_port;
433 	fl4->flowi4_proto = IPPROTO_SCTP;
434 	if (asoc) {
435 		fl4->flowi4_tos = RT_CONN_FLAGS(asoc->base.sk);
436 		fl4->flowi4_oif = asoc->base.sk->sk_bound_dev_if;
437 		fl4->fl4_sport = htons(asoc->base.bind_addr.port);
438 	}
439 	if (saddr) {
440 		fl4->saddr = saddr->v4.sin_addr.s_addr;
441 		fl4->fl4_sport = saddr->v4.sin_port;
442 	}
443 
444 	pr_debug("%s: dst:%pI4, src:%pI4 - ", __func__, &fl4->daddr,
445 		 &fl4->saddr);
446 
447 	rt = ip_route_output_key(sock_net(sk), fl4);
448 	if (!IS_ERR(rt))
449 		dst = &rt->dst;
450 
451 	/* If there is no association or if a source address is passed, no
452 	 * more validation is required.
453 	 */
454 	if (!asoc || saddr)
455 		goto out;
456 
457 	bp = &asoc->base.bind_addr;
458 
459 	if (dst) {
460 		/* Walk through the bind address list and look for a bind
461 		 * address that matches the source address of the returned dst.
462 		 */
463 		sctp_v4_dst_saddr(&dst_saddr, fl4, htons(bp->port));
464 		rcu_read_lock();
465 		list_for_each_entry_rcu(laddr, &bp->address_list, list) {
466 			if (!laddr->valid || (laddr->state == SCTP_ADDR_DEL) ||
467 			    (laddr->state != SCTP_ADDR_SRC &&
468 			    !asoc->src_out_of_asoc_ok))
469 				continue;
470 			if (sctp_v4_cmp_addr(&dst_saddr, &laddr->a))
471 				goto out_unlock;
472 		}
473 		rcu_read_unlock();
474 
475 		/* None of the bound addresses match the source address of the
476 		 * dst. So release it.
477 		 */
478 		dst_release(dst);
479 		dst = NULL;
480 	}
481 
482 	/* Walk through the bind address list and try to get a dst that
483 	 * matches a bind address as the source address.
484 	 */
485 	rcu_read_lock();
486 	list_for_each_entry_rcu(laddr, &bp->address_list, list) {
487 		struct net_device *odev;
488 
489 		if (!laddr->valid)
490 			continue;
491 		if (laddr->state != SCTP_ADDR_SRC ||
492 		    AF_INET != laddr->a.sa.sa_family)
493 			continue;
494 
495 		fl4->fl4_sport = laddr->a.v4.sin_port;
496 		flowi4_update_output(fl4,
497 				     asoc->base.sk->sk_bound_dev_if,
498 				     RT_CONN_FLAGS(asoc->base.sk),
499 				     daddr->v4.sin_addr.s_addr,
500 				     laddr->a.v4.sin_addr.s_addr);
501 
502 		rt = ip_route_output_key(sock_net(sk), fl4);
503 		if (IS_ERR(rt))
504 			continue;
505 
506 		/* Ensure the src address belongs to the output
507 		 * interface.
508 		 */
509 		odev = __ip_dev_find(sock_net(sk), laddr->a.v4.sin_addr.s_addr,
510 				     false);
511 		if (!odev || odev->ifindex != fl4->flowi4_oif) {
512 			if (!dst)
513 				dst = &rt->dst;
514 			else
515 				dst_release(&rt->dst);
516 			continue;
517 		}
518 
519 		dst_release(dst);
520 		dst = &rt->dst;
521 		break;
522 	}
523 
524 out_unlock:
525 	rcu_read_unlock();
526 out:
527 	t->dst = dst;
528 	if (dst)
529 		pr_debug("rt_dst:%pI4, rt_src:%pI4\n",
530 			 &fl4->daddr, &fl4->saddr);
531 	else
532 		pr_debug("no route\n");
533 }
534 
535 /* For v4, the source address is cached in the route entry(dst). So no need
536  * to cache it separately and hence this is an empty routine.
537  */
538 static void sctp_v4_get_saddr(struct sctp_sock *sk,
539 			      struct sctp_transport *t,
540 			      struct flowi *fl)
541 {
542 	union sctp_addr *saddr = &t->saddr;
543 	struct rtable *rt = (struct rtable *)t->dst;
544 
545 	if (rt) {
546 		saddr->v4.sin_family = AF_INET;
547 		saddr->v4.sin_addr.s_addr = fl->u.ip4.saddr;
548 	}
549 }
550 
551 /* What interface did this skb arrive on? */
552 static int sctp_v4_skb_iif(const struct sk_buff *skb)
553 {
554 	return inet_iif(skb);
555 }
556 
557 /* Was this packet marked by Explicit Congestion Notification? */
558 static int sctp_v4_is_ce(const struct sk_buff *skb)
559 {
560 	return INET_ECN_is_ce(ip_hdr(skb)->tos);
561 }
562 
563 /* Create and initialize a new sk for the socket returned by accept(). */
564 static struct sock *sctp_v4_create_accept_sk(struct sock *sk,
565 					     struct sctp_association *asoc,
566 					     bool kern)
567 {
568 	struct sock *newsk = sk_alloc(sock_net(sk), PF_INET, GFP_KERNEL,
569 			sk->sk_prot, kern);
570 	struct inet_sock *newinet;
571 
572 	if (!newsk)
573 		goto out;
574 
575 	sock_init_data(NULL, newsk);
576 
577 	sctp_copy_sock(newsk, sk, asoc);
578 	sock_reset_flag(newsk, SOCK_ZAPPED);
579 
580 	sctp_v4_copy_ip_options(sk, newsk);
581 
582 	newinet = inet_sk(newsk);
583 
584 	newinet->inet_daddr = asoc->peer.primary_addr.v4.sin_addr.s_addr;
585 
586 	sk_refcnt_debug_inc(newsk);
587 
588 	if (newsk->sk_prot->init(newsk)) {
589 		sk_common_release(newsk);
590 		newsk = NULL;
591 	}
592 
593 out:
594 	return newsk;
595 }
596 
597 static int sctp_v4_addr_to_user(struct sctp_sock *sp, union sctp_addr *addr)
598 {
599 	/* No address mapping for V4 sockets */
600 	return sizeof(struct sockaddr_in);
601 }
602 
603 /* Dump the v4 addr to the seq file. */
604 static void sctp_v4_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
605 {
606 	seq_printf(seq, "%pI4 ", &addr->v4.sin_addr);
607 }
608 
609 static void sctp_v4_ecn_capable(struct sock *sk)
610 {
611 	INET_ECN_xmit(sk);
612 }
613 
614 static void sctp_addr_wq_timeout_handler(struct timer_list *t)
615 {
616 	struct net *net = from_timer(net, t, sctp.addr_wq_timer);
617 	struct sctp_sockaddr_entry *addrw, *temp;
618 	struct sctp_sock *sp;
619 
620 	spin_lock_bh(&net->sctp.addr_wq_lock);
621 
622 	list_for_each_entry_safe(addrw, temp, &net->sctp.addr_waitq, list) {
623 		pr_debug("%s: the first ent in wq:%p is addr:%pISc for cmd:%d at "
624 			 "entry:%p\n", __func__, &net->sctp.addr_waitq, &addrw->a.sa,
625 			 addrw->state, addrw);
626 
627 #if IS_ENABLED(CONFIG_IPV6)
628 		/* Now we send an ASCONF for each association */
629 		/* Note. we currently don't handle link local IPv6 addressees */
630 		if (addrw->a.sa.sa_family == AF_INET6) {
631 			struct in6_addr *in6;
632 
633 			if (ipv6_addr_type(&addrw->a.v6.sin6_addr) &
634 			    IPV6_ADDR_LINKLOCAL)
635 				goto free_next;
636 
637 			in6 = (struct in6_addr *)&addrw->a.v6.sin6_addr;
638 			if (ipv6_chk_addr(net, in6, NULL, 0) == 0 &&
639 			    addrw->state == SCTP_ADDR_NEW) {
640 				unsigned long timeo_val;
641 
642 				pr_debug("%s: this is on DAD, trying %d sec "
643 					 "later\n", __func__,
644 					 SCTP_ADDRESS_TICK_DELAY);
645 
646 				timeo_val = jiffies;
647 				timeo_val += msecs_to_jiffies(SCTP_ADDRESS_TICK_DELAY);
648 				mod_timer(&net->sctp.addr_wq_timer, timeo_val);
649 				break;
650 			}
651 		}
652 #endif
653 		list_for_each_entry(sp, &net->sctp.auto_asconf_splist, auto_asconf_list) {
654 			struct sock *sk;
655 
656 			sk = sctp_opt2sk(sp);
657 			/* ignore bound-specific endpoints */
658 			if (!sctp_is_ep_boundall(sk))
659 				continue;
660 			bh_lock_sock(sk);
661 			if (sctp_asconf_mgmt(sp, addrw) < 0)
662 				pr_debug("%s: sctp_asconf_mgmt failed\n", __func__);
663 			bh_unlock_sock(sk);
664 		}
665 #if IS_ENABLED(CONFIG_IPV6)
666 free_next:
667 #endif
668 		list_del(&addrw->list);
669 		kfree(addrw);
670 	}
671 	spin_unlock_bh(&net->sctp.addr_wq_lock);
672 }
673 
674 static void sctp_free_addr_wq(struct net *net)
675 {
676 	struct sctp_sockaddr_entry *addrw;
677 	struct sctp_sockaddr_entry *temp;
678 
679 	spin_lock_bh(&net->sctp.addr_wq_lock);
680 	del_timer(&net->sctp.addr_wq_timer);
681 	list_for_each_entry_safe(addrw, temp, &net->sctp.addr_waitq, list) {
682 		list_del(&addrw->list);
683 		kfree(addrw);
684 	}
685 	spin_unlock_bh(&net->sctp.addr_wq_lock);
686 }
687 
688 /* lookup the entry for the same address in the addr_waitq
689  * sctp_addr_wq MUST be locked
690  */
691 static struct sctp_sockaddr_entry *sctp_addr_wq_lookup(struct net *net,
692 					struct sctp_sockaddr_entry *addr)
693 {
694 	struct sctp_sockaddr_entry *addrw;
695 
696 	list_for_each_entry(addrw, &net->sctp.addr_waitq, list) {
697 		if (addrw->a.sa.sa_family != addr->a.sa.sa_family)
698 			continue;
699 		if (addrw->a.sa.sa_family == AF_INET) {
700 			if (addrw->a.v4.sin_addr.s_addr ==
701 			    addr->a.v4.sin_addr.s_addr)
702 				return addrw;
703 		} else if (addrw->a.sa.sa_family == AF_INET6) {
704 			if (ipv6_addr_equal(&addrw->a.v6.sin6_addr,
705 			    &addr->a.v6.sin6_addr))
706 				return addrw;
707 		}
708 	}
709 	return NULL;
710 }
711 
712 void sctp_addr_wq_mgmt(struct net *net, struct sctp_sockaddr_entry *addr, int cmd)
713 {
714 	struct sctp_sockaddr_entry *addrw;
715 	unsigned long timeo_val;
716 
717 	/* first, we check if an opposite message already exist in the queue.
718 	 * If we found such message, it is removed.
719 	 * This operation is a bit stupid, but the DHCP client attaches the
720 	 * new address after a couple of addition and deletion of that address
721 	 */
722 
723 	spin_lock_bh(&net->sctp.addr_wq_lock);
724 	/* Offsets existing events in addr_wq */
725 	addrw = sctp_addr_wq_lookup(net, addr);
726 	if (addrw) {
727 		if (addrw->state != cmd) {
728 			pr_debug("%s: offsets existing entry for %d, addr:%pISc "
729 				 "in wq:%p\n", __func__, addrw->state, &addrw->a.sa,
730 				 &net->sctp.addr_waitq);
731 
732 			list_del(&addrw->list);
733 			kfree(addrw);
734 		}
735 		spin_unlock_bh(&net->sctp.addr_wq_lock);
736 		return;
737 	}
738 
739 	/* OK, we have to add the new address to the wait queue */
740 	addrw = kmemdup(addr, sizeof(struct sctp_sockaddr_entry), GFP_ATOMIC);
741 	if (addrw == NULL) {
742 		spin_unlock_bh(&net->sctp.addr_wq_lock);
743 		return;
744 	}
745 	addrw->state = cmd;
746 	list_add_tail(&addrw->list, &net->sctp.addr_waitq);
747 
748 	pr_debug("%s: add new entry for cmd:%d, addr:%pISc in wq:%p\n",
749 		 __func__, addrw->state, &addrw->a.sa, &net->sctp.addr_waitq);
750 
751 	if (!timer_pending(&net->sctp.addr_wq_timer)) {
752 		timeo_val = jiffies;
753 		timeo_val += msecs_to_jiffies(SCTP_ADDRESS_TICK_DELAY);
754 		mod_timer(&net->sctp.addr_wq_timer, timeo_val);
755 	}
756 	spin_unlock_bh(&net->sctp.addr_wq_lock);
757 }
758 
759 /* Event handler for inet address addition/deletion events.
760  * The sctp_local_addr_list needs to be protocted by a spin lock since
761  * multiple notifiers (say IPv4 and IPv6) may be running at the same
762  * time and thus corrupt the list.
763  * The reader side is protected with RCU.
764  */
765 static int sctp_inetaddr_event(struct notifier_block *this, unsigned long ev,
766 			       void *ptr)
767 {
768 	struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
769 	struct sctp_sockaddr_entry *addr = NULL;
770 	struct sctp_sockaddr_entry *temp;
771 	struct net *net = dev_net(ifa->ifa_dev->dev);
772 	int found = 0;
773 
774 	switch (ev) {
775 	case NETDEV_UP:
776 		addr = kmalloc(sizeof(struct sctp_sockaddr_entry), GFP_ATOMIC);
777 		if (addr) {
778 			addr->a.v4.sin_family = AF_INET;
779 			addr->a.v4.sin_port = 0;
780 			addr->a.v4.sin_addr.s_addr = ifa->ifa_local;
781 			addr->valid = 1;
782 			spin_lock_bh(&net->sctp.local_addr_lock);
783 			list_add_tail_rcu(&addr->list, &net->sctp.local_addr_list);
784 			sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_NEW);
785 			spin_unlock_bh(&net->sctp.local_addr_lock);
786 		}
787 		break;
788 	case NETDEV_DOWN:
789 		spin_lock_bh(&net->sctp.local_addr_lock);
790 		list_for_each_entry_safe(addr, temp,
791 					&net->sctp.local_addr_list, list) {
792 			if (addr->a.sa.sa_family == AF_INET &&
793 					addr->a.v4.sin_addr.s_addr ==
794 					ifa->ifa_local) {
795 				sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_DEL);
796 				found = 1;
797 				addr->valid = 0;
798 				list_del_rcu(&addr->list);
799 				break;
800 			}
801 		}
802 		spin_unlock_bh(&net->sctp.local_addr_lock);
803 		if (found)
804 			kfree_rcu(addr, rcu);
805 		break;
806 	}
807 
808 	return NOTIFY_DONE;
809 }
810 
811 /*
812  * Initialize the control inode/socket with a control endpoint data
813  * structure.  This endpoint is reserved exclusively for the OOTB processing.
814  */
815 static int sctp_ctl_sock_init(struct net *net)
816 {
817 	int err;
818 	sa_family_t family = PF_INET;
819 
820 	if (sctp_get_pf_specific(PF_INET6))
821 		family = PF_INET6;
822 
823 	err = inet_ctl_sock_create(&net->sctp.ctl_sock, family,
824 				   SOCK_SEQPACKET, IPPROTO_SCTP, net);
825 
826 	/* If IPv6 socket could not be created, try the IPv4 socket */
827 	if (err < 0 && family == PF_INET6)
828 		err = inet_ctl_sock_create(&net->sctp.ctl_sock, AF_INET,
829 					   SOCK_SEQPACKET, IPPROTO_SCTP,
830 					   net);
831 
832 	if (err < 0) {
833 		pr_err("Failed to create the SCTP control socket\n");
834 		return err;
835 	}
836 	return 0;
837 }
838 
839 /* Register address family specific functions. */
840 int sctp_register_af(struct sctp_af *af)
841 {
842 	switch (af->sa_family) {
843 	case AF_INET:
844 		if (sctp_af_v4_specific)
845 			return 0;
846 		sctp_af_v4_specific = af;
847 		break;
848 	case AF_INET6:
849 		if (sctp_af_v6_specific)
850 			return 0;
851 		sctp_af_v6_specific = af;
852 		break;
853 	default:
854 		return 0;
855 	}
856 
857 	INIT_LIST_HEAD(&af->list);
858 	list_add_tail(&af->list, &sctp_address_families);
859 	return 1;
860 }
861 
862 /* Get the table of functions for manipulating a particular address
863  * family.
864  */
865 struct sctp_af *sctp_get_af_specific(sa_family_t family)
866 {
867 	switch (family) {
868 	case AF_INET:
869 		return sctp_af_v4_specific;
870 	case AF_INET6:
871 		return sctp_af_v6_specific;
872 	default:
873 		return NULL;
874 	}
875 }
876 
877 /* Common code to initialize a AF_INET msg_name. */
878 static void sctp_inet_msgname(char *msgname, int *addr_len)
879 {
880 	struct sockaddr_in *sin;
881 
882 	sin = (struct sockaddr_in *)msgname;
883 	*addr_len = sizeof(struct sockaddr_in);
884 	sin->sin_family = AF_INET;
885 	memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
886 }
887 
888 /* Copy the primary address of the peer primary address as the msg_name. */
889 static void sctp_inet_event_msgname(struct sctp_ulpevent *event, char *msgname,
890 				    int *addr_len)
891 {
892 	struct sockaddr_in *sin, *sinfrom;
893 
894 	if (msgname) {
895 		struct sctp_association *asoc;
896 
897 		asoc = event->asoc;
898 		sctp_inet_msgname(msgname, addr_len);
899 		sin = (struct sockaddr_in *)msgname;
900 		sinfrom = &asoc->peer.primary_addr.v4;
901 		sin->sin_port = htons(asoc->peer.port);
902 		sin->sin_addr.s_addr = sinfrom->sin_addr.s_addr;
903 	}
904 }
905 
906 /* Initialize and copy out a msgname from an inbound skb. */
907 static void sctp_inet_skb_msgname(struct sk_buff *skb, char *msgname, int *len)
908 {
909 	if (msgname) {
910 		struct sctphdr *sh = sctp_hdr(skb);
911 		struct sockaddr_in *sin = (struct sockaddr_in *)msgname;
912 
913 		sctp_inet_msgname(msgname, len);
914 		sin->sin_port = sh->source;
915 		sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
916 	}
917 }
918 
919 /* Do we support this AF? */
920 static int sctp_inet_af_supported(sa_family_t family, struct sctp_sock *sp)
921 {
922 	/* PF_INET only supports AF_INET addresses. */
923 	return AF_INET == family;
924 }
925 
926 /* Address matching with wildcards allowed. */
927 static int sctp_inet_cmp_addr(const union sctp_addr *addr1,
928 			      const union sctp_addr *addr2,
929 			      struct sctp_sock *opt)
930 {
931 	/* PF_INET only supports AF_INET addresses. */
932 	if (addr1->sa.sa_family != addr2->sa.sa_family)
933 		return 0;
934 	if (htonl(INADDR_ANY) == addr1->v4.sin_addr.s_addr ||
935 	    htonl(INADDR_ANY) == addr2->v4.sin_addr.s_addr)
936 		return 1;
937 	if (addr1->v4.sin_addr.s_addr == addr2->v4.sin_addr.s_addr)
938 		return 1;
939 
940 	return 0;
941 }
942 
943 /* Verify that provided sockaddr looks bindable.  Common verification has
944  * already been taken care of.
945  */
946 static int sctp_inet_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
947 {
948 	return sctp_v4_available(addr, opt);
949 }
950 
951 /* Verify that sockaddr looks sendable.  Common verification has already
952  * been taken care of.
953  */
954 static int sctp_inet_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
955 {
956 	return 1;
957 }
958 
959 /* Fill in Supported Address Type information for INIT and INIT-ACK
960  * chunks.  Returns number of addresses supported.
961  */
962 static int sctp_inet_supported_addrs(const struct sctp_sock *opt,
963 				     __be16 *types)
964 {
965 	types[0] = SCTP_PARAM_IPV4_ADDRESS;
966 	return 1;
967 }
968 
969 /* Wrapper routine that calls the ip transmit routine. */
970 static inline int sctp_v4_xmit(struct sk_buff *skb,
971 			       struct sctp_transport *transport)
972 {
973 	struct inet_sock *inet = inet_sk(skb->sk);
974 
975 	pr_debug("%s: skb:%p, len:%d, src:%pI4, dst:%pI4\n", __func__, skb,
976 		 skb->len, &transport->fl.u.ip4.saddr, &transport->fl.u.ip4.daddr);
977 
978 	inet->pmtudisc = transport->param_flags & SPP_PMTUD_ENABLE ?
979 			 IP_PMTUDISC_DO : IP_PMTUDISC_DONT;
980 
981 	SCTP_INC_STATS(sock_net(&inet->sk), SCTP_MIB_OUTSCTPPACKS);
982 
983 	return ip_queue_xmit(&inet->sk, skb, &transport->fl);
984 }
985 
986 static struct sctp_af sctp_af_inet;
987 
988 static struct sctp_pf sctp_pf_inet = {
989 	.event_msgname = sctp_inet_event_msgname,
990 	.skb_msgname   = sctp_inet_skb_msgname,
991 	.af_supported  = sctp_inet_af_supported,
992 	.cmp_addr      = sctp_inet_cmp_addr,
993 	.bind_verify   = sctp_inet_bind_verify,
994 	.send_verify   = sctp_inet_send_verify,
995 	.supported_addrs = sctp_inet_supported_addrs,
996 	.create_accept_sk = sctp_v4_create_accept_sk,
997 	.addr_to_user  = sctp_v4_addr_to_user,
998 	.to_sk_saddr   = sctp_v4_to_sk_saddr,
999 	.to_sk_daddr   = sctp_v4_to_sk_daddr,
1000 	.copy_ip_options = sctp_v4_copy_ip_options,
1001 	.af            = &sctp_af_inet
1002 };
1003 
1004 /* Notifier for inetaddr addition/deletion events.  */
1005 static struct notifier_block sctp_inetaddr_notifier = {
1006 	.notifier_call = sctp_inetaddr_event,
1007 };
1008 
1009 /* Socket operations.  */
1010 static const struct proto_ops inet_seqpacket_ops = {
1011 	.family		   = PF_INET,
1012 	.owner		   = THIS_MODULE,
1013 	.release	   = inet_release,	/* Needs to be wrapped... */
1014 	.bind		   = inet_bind,
1015 	.connect	   = sctp_inet_connect,
1016 	.socketpair	   = sock_no_socketpair,
1017 	.accept		   = inet_accept,
1018 	.getname	   = inet_getname,	/* Semantics are different.  */
1019 	.poll_mask	   = sctp_poll_mask,
1020 	.ioctl		   = inet_ioctl,
1021 	.listen		   = sctp_inet_listen,
1022 	.shutdown	   = inet_shutdown,	/* Looks harmless.  */
1023 	.setsockopt	   = sock_common_setsockopt, /* IP_SOL IP_OPTION is a problem */
1024 	.getsockopt	   = sock_common_getsockopt,
1025 	.sendmsg	   = inet_sendmsg,
1026 	.recvmsg	   = inet_recvmsg,
1027 	.mmap		   = sock_no_mmap,
1028 	.sendpage	   = sock_no_sendpage,
1029 #ifdef CONFIG_COMPAT
1030 	.compat_setsockopt = compat_sock_common_setsockopt,
1031 	.compat_getsockopt = compat_sock_common_getsockopt,
1032 #endif
1033 };
1034 
1035 /* Registration with AF_INET family.  */
1036 static struct inet_protosw sctp_seqpacket_protosw = {
1037 	.type       = SOCK_SEQPACKET,
1038 	.protocol   = IPPROTO_SCTP,
1039 	.prot       = &sctp_prot,
1040 	.ops        = &inet_seqpacket_ops,
1041 	.flags      = SCTP_PROTOSW_FLAG
1042 };
1043 static struct inet_protosw sctp_stream_protosw = {
1044 	.type       = SOCK_STREAM,
1045 	.protocol   = IPPROTO_SCTP,
1046 	.prot       = &sctp_prot,
1047 	.ops        = &inet_seqpacket_ops,
1048 	.flags      = SCTP_PROTOSW_FLAG
1049 };
1050 
1051 /* Register with IP layer.  */
1052 static const struct net_protocol sctp_protocol = {
1053 	.handler     = sctp_rcv,
1054 	.err_handler = sctp_v4_err,
1055 	.no_policy   = 1,
1056 	.netns_ok    = 1,
1057 	.icmp_strict_tag_validation = 1,
1058 };
1059 
1060 /* IPv4 address related functions.  */
1061 static struct sctp_af sctp_af_inet = {
1062 	.sa_family	   = AF_INET,
1063 	.sctp_xmit	   = sctp_v4_xmit,
1064 	.setsockopt	   = ip_setsockopt,
1065 	.getsockopt	   = ip_getsockopt,
1066 	.get_dst	   = sctp_v4_get_dst,
1067 	.get_saddr	   = sctp_v4_get_saddr,
1068 	.copy_addrlist	   = sctp_v4_copy_addrlist,
1069 	.from_skb	   = sctp_v4_from_skb,
1070 	.from_sk	   = sctp_v4_from_sk,
1071 	.from_addr_param   = sctp_v4_from_addr_param,
1072 	.to_addr_param	   = sctp_v4_to_addr_param,
1073 	.cmp_addr	   = sctp_v4_cmp_addr,
1074 	.addr_valid	   = sctp_v4_addr_valid,
1075 	.inaddr_any	   = sctp_v4_inaddr_any,
1076 	.is_any		   = sctp_v4_is_any,
1077 	.available	   = sctp_v4_available,
1078 	.scope		   = sctp_v4_scope,
1079 	.skb_iif	   = sctp_v4_skb_iif,
1080 	.is_ce		   = sctp_v4_is_ce,
1081 	.seq_dump_addr	   = sctp_v4_seq_dump_addr,
1082 	.ecn_capable	   = sctp_v4_ecn_capable,
1083 	.net_header_len	   = sizeof(struct iphdr),
1084 	.sockaddr_len	   = sizeof(struct sockaddr_in),
1085 	.ip_options_len	   = sctp_v4_ip_options_len,
1086 #ifdef CONFIG_COMPAT
1087 	.compat_setsockopt = compat_ip_setsockopt,
1088 	.compat_getsockopt = compat_ip_getsockopt,
1089 #endif
1090 };
1091 
1092 struct sctp_pf *sctp_get_pf_specific(sa_family_t family)
1093 {
1094 	switch (family) {
1095 	case PF_INET:
1096 		return sctp_pf_inet_specific;
1097 	case PF_INET6:
1098 		return sctp_pf_inet6_specific;
1099 	default:
1100 		return NULL;
1101 	}
1102 }
1103 
1104 /* Register the PF specific function table.  */
1105 int sctp_register_pf(struct sctp_pf *pf, sa_family_t family)
1106 {
1107 	switch (family) {
1108 	case PF_INET:
1109 		if (sctp_pf_inet_specific)
1110 			return 0;
1111 		sctp_pf_inet_specific = pf;
1112 		break;
1113 	case PF_INET6:
1114 		if (sctp_pf_inet6_specific)
1115 			return 0;
1116 		sctp_pf_inet6_specific = pf;
1117 		break;
1118 	default:
1119 		return 0;
1120 	}
1121 	return 1;
1122 }
1123 
1124 static inline int init_sctp_mibs(struct net *net)
1125 {
1126 	net->sctp.sctp_statistics = alloc_percpu(struct sctp_mib);
1127 	if (!net->sctp.sctp_statistics)
1128 		return -ENOMEM;
1129 	return 0;
1130 }
1131 
1132 static inline void cleanup_sctp_mibs(struct net *net)
1133 {
1134 	free_percpu(net->sctp.sctp_statistics);
1135 }
1136 
1137 static void sctp_v4_pf_init(void)
1138 {
1139 	/* Initialize the SCTP specific PF functions. */
1140 	sctp_register_pf(&sctp_pf_inet, PF_INET);
1141 	sctp_register_af(&sctp_af_inet);
1142 }
1143 
1144 static void sctp_v4_pf_exit(void)
1145 {
1146 	list_del(&sctp_af_inet.list);
1147 }
1148 
1149 static int sctp_v4_protosw_init(void)
1150 {
1151 	int rc;
1152 
1153 	rc = proto_register(&sctp_prot, 1);
1154 	if (rc)
1155 		return rc;
1156 
1157 	/* Register SCTP(UDP and TCP style) with socket layer.  */
1158 	inet_register_protosw(&sctp_seqpacket_protosw);
1159 	inet_register_protosw(&sctp_stream_protosw);
1160 
1161 	return 0;
1162 }
1163 
1164 static void sctp_v4_protosw_exit(void)
1165 {
1166 	inet_unregister_protosw(&sctp_stream_protosw);
1167 	inet_unregister_protosw(&sctp_seqpacket_protosw);
1168 	proto_unregister(&sctp_prot);
1169 }
1170 
1171 static int sctp_v4_add_protocol(void)
1172 {
1173 	/* Register notifier for inet address additions/deletions. */
1174 	register_inetaddr_notifier(&sctp_inetaddr_notifier);
1175 
1176 	/* Register SCTP with inet layer.  */
1177 	if (inet_add_protocol(&sctp_protocol, IPPROTO_SCTP) < 0)
1178 		return -EAGAIN;
1179 
1180 	return 0;
1181 }
1182 
1183 static void sctp_v4_del_protocol(void)
1184 {
1185 	inet_del_protocol(&sctp_protocol, IPPROTO_SCTP);
1186 	unregister_inetaddr_notifier(&sctp_inetaddr_notifier);
1187 }
1188 
1189 static int __net_init sctp_defaults_init(struct net *net)
1190 {
1191 	int status;
1192 
1193 	/*
1194 	 * 14. Suggested SCTP Protocol Parameter Values
1195 	 */
1196 	/* The following protocol parameters are RECOMMENDED:  */
1197 	/* RTO.Initial              - 3  seconds */
1198 	net->sctp.rto_initial			= SCTP_RTO_INITIAL;
1199 	/* RTO.Min                  - 1  second */
1200 	net->sctp.rto_min	 		= SCTP_RTO_MIN;
1201 	/* RTO.Max                 -  60 seconds */
1202 	net->sctp.rto_max 			= SCTP_RTO_MAX;
1203 	/* RTO.Alpha                - 1/8 */
1204 	net->sctp.rto_alpha			= SCTP_RTO_ALPHA;
1205 	/* RTO.Beta                 - 1/4 */
1206 	net->sctp.rto_beta			= SCTP_RTO_BETA;
1207 
1208 	/* Valid.Cookie.Life        - 60  seconds */
1209 	net->sctp.valid_cookie_life		= SCTP_DEFAULT_COOKIE_LIFE;
1210 
1211 	/* Whether Cookie Preservative is enabled(1) or not(0) */
1212 	net->sctp.cookie_preserve_enable 	= 1;
1213 
1214 	/* Default sctp sockets to use md5 as their hmac alg */
1215 #if defined (CONFIG_SCTP_DEFAULT_COOKIE_HMAC_MD5)
1216 	net->sctp.sctp_hmac_alg			= "md5";
1217 #elif defined (CONFIG_SCTP_DEFAULT_COOKIE_HMAC_SHA1)
1218 	net->sctp.sctp_hmac_alg			= "sha1";
1219 #else
1220 	net->sctp.sctp_hmac_alg			= NULL;
1221 #endif
1222 
1223 	/* Max.Burst		    - 4 */
1224 	net->sctp.max_burst			= SCTP_DEFAULT_MAX_BURST;
1225 
1226 	/* Enable pf state by default */
1227 	net->sctp.pf_enable = 1;
1228 
1229 	/* Association.Max.Retrans  - 10 attempts
1230 	 * Path.Max.Retrans         - 5  attempts (per destination address)
1231 	 * Max.Init.Retransmits     - 8  attempts
1232 	 */
1233 	net->sctp.max_retrans_association	= 10;
1234 	net->sctp.max_retrans_path		= 5;
1235 	net->sctp.max_retrans_init		= 8;
1236 
1237 	/* Sendbuffer growth	    - do per-socket accounting */
1238 	net->sctp.sndbuf_policy			= 0;
1239 
1240 	/* Rcvbuffer growth	    - do per-socket accounting */
1241 	net->sctp.rcvbuf_policy			= 0;
1242 
1243 	/* HB.interval              - 30 seconds */
1244 	net->sctp.hb_interval			= SCTP_DEFAULT_TIMEOUT_HEARTBEAT;
1245 
1246 	/* delayed SACK timeout */
1247 	net->sctp.sack_timeout			= SCTP_DEFAULT_TIMEOUT_SACK;
1248 
1249 	/* Disable ADDIP by default. */
1250 	net->sctp.addip_enable = 0;
1251 	net->sctp.addip_noauth = 0;
1252 	net->sctp.default_auto_asconf = 0;
1253 
1254 	/* Enable PR-SCTP by default. */
1255 	net->sctp.prsctp_enable = 1;
1256 
1257 	/* Disable RECONF by default. */
1258 	net->sctp.reconf_enable = 0;
1259 
1260 	/* Disable AUTH by default. */
1261 	net->sctp.auth_enable = 0;
1262 
1263 	/* Set SCOPE policy to enabled */
1264 	net->sctp.scope_policy = SCTP_SCOPE_POLICY_ENABLE;
1265 
1266 	/* Set the default rwnd update threshold */
1267 	net->sctp.rwnd_upd_shift = SCTP_DEFAULT_RWND_SHIFT;
1268 
1269 	/* Initialize maximum autoclose timeout. */
1270 	net->sctp.max_autoclose		= INT_MAX / HZ;
1271 
1272 	status = sctp_sysctl_net_register(net);
1273 	if (status)
1274 		goto err_sysctl_register;
1275 
1276 	/* Allocate and initialise sctp mibs.  */
1277 	status = init_sctp_mibs(net);
1278 	if (status)
1279 		goto err_init_mibs;
1280 
1281 #ifdef CONFIG_PROC_FS
1282 	/* Initialize proc fs directory.  */
1283 	status = sctp_proc_init(net);
1284 	if (status)
1285 		goto err_init_proc;
1286 #endif
1287 
1288 	sctp_dbg_objcnt_init(net);
1289 
1290 	/* Initialize the local address list. */
1291 	INIT_LIST_HEAD(&net->sctp.local_addr_list);
1292 	spin_lock_init(&net->sctp.local_addr_lock);
1293 	sctp_get_local_addr_list(net);
1294 
1295 	/* Initialize the address event list */
1296 	INIT_LIST_HEAD(&net->sctp.addr_waitq);
1297 	INIT_LIST_HEAD(&net->sctp.auto_asconf_splist);
1298 	spin_lock_init(&net->sctp.addr_wq_lock);
1299 	net->sctp.addr_wq_timer.expires = 0;
1300 	timer_setup(&net->sctp.addr_wq_timer, sctp_addr_wq_timeout_handler, 0);
1301 
1302 	return 0;
1303 
1304 #ifdef CONFIG_PROC_FS
1305 err_init_proc:
1306 	cleanup_sctp_mibs(net);
1307 #endif
1308 err_init_mibs:
1309 	sctp_sysctl_net_unregister(net);
1310 err_sysctl_register:
1311 	return status;
1312 }
1313 
1314 static void __net_exit sctp_defaults_exit(struct net *net)
1315 {
1316 	/* Free the local address list */
1317 	sctp_free_addr_wq(net);
1318 	sctp_free_local_addr_list(net);
1319 
1320 #ifdef CONFIG_PROC_FS
1321 	remove_proc_subtree("sctp", net->proc_net);
1322 	net->sctp.proc_net_sctp = NULL;
1323 #endif
1324 	cleanup_sctp_mibs(net);
1325 	sctp_sysctl_net_unregister(net);
1326 }
1327 
1328 static struct pernet_operations sctp_defaults_ops = {
1329 	.init = sctp_defaults_init,
1330 	.exit = sctp_defaults_exit,
1331 };
1332 
1333 static int __net_init sctp_ctrlsock_init(struct net *net)
1334 {
1335 	int status;
1336 
1337 	/* Initialize the control inode/socket for handling OOTB packets.  */
1338 	status = sctp_ctl_sock_init(net);
1339 	if (status)
1340 		pr_err("Failed to initialize the SCTP control sock\n");
1341 
1342 	return status;
1343 }
1344 
1345 static void __net_init sctp_ctrlsock_exit(struct net *net)
1346 {
1347 	/* Free the control endpoint.  */
1348 	inet_ctl_sock_destroy(net->sctp.ctl_sock);
1349 }
1350 
1351 static struct pernet_operations sctp_ctrlsock_ops = {
1352 	.init = sctp_ctrlsock_init,
1353 	.exit = sctp_ctrlsock_exit,
1354 };
1355 
1356 /* Initialize the universe into something sensible.  */
1357 static __init int sctp_init(void)
1358 {
1359 	int i;
1360 	int status = -EINVAL;
1361 	unsigned long goal;
1362 	unsigned long limit;
1363 	int max_share;
1364 	int order;
1365 	int num_entries;
1366 	int max_entry_order;
1367 
1368 	sock_skb_cb_check_size(sizeof(struct sctp_ulpevent));
1369 
1370 	/* Allocate bind_bucket and chunk caches. */
1371 	status = -ENOBUFS;
1372 	sctp_bucket_cachep = kmem_cache_create("sctp_bind_bucket",
1373 					       sizeof(struct sctp_bind_bucket),
1374 					       0, SLAB_HWCACHE_ALIGN,
1375 					       NULL);
1376 	if (!sctp_bucket_cachep)
1377 		goto out;
1378 
1379 	sctp_chunk_cachep = kmem_cache_create("sctp_chunk",
1380 					       sizeof(struct sctp_chunk),
1381 					       0, SLAB_HWCACHE_ALIGN,
1382 					       NULL);
1383 	if (!sctp_chunk_cachep)
1384 		goto err_chunk_cachep;
1385 
1386 	status = percpu_counter_init(&sctp_sockets_allocated, 0, GFP_KERNEL);
1387 	if (status)
1388 		goto err_percpu_counter_init;
1389 
1390 	/* Implementation specific variables. */
1391 
1392 	/* Initialize default stream count setup information. */
1393 	sctp_max_instreams    		= SCTP_DEFAULT_INSTREAMS;
1394 	sctp_max_outstreams   		= SCTP_DEFAULT_OUTSTREAMS;
1395 
1396 	/* Initialize handle used for association ids. */
1397 	idr_init(&sctp_assocs_id);
1398 
1399 	limit = nr_free_buffer_pages() / 8;
1400 	limit = max(limit, 128UL);
1401 	sysctl_sctp_mem[0] = limit / 4 * 3;
1402 	sysctl_sctp_mem[1] = limit;
1403 	sysctl_sctp_mem[2] = sysctl_sctp_mem[0] * 2;
1404 
1405 	/* Set per-socket limits to no more than 1/128 the pressure threshold*/
1406 	limit = (sysctl_sctp_mem[1]) << (PAGE_SHIFT - 7);
1407 	max_share = min(4UL*1024*1024, limit);
1408 
1409 	sysctl_sctp_rmem[0] = SK_MEM_QUANTUM; /* give each asoc 1 page min */
1410 	sysctl_sctp_rmem[1] = 1500 * SKB_TRUESIZE(1);
1411 	sysctl_sctp_rmem[2] = max(sysctl_sctp_rmem[1], max_share);
1412 
1413 	sysctl_sctp_wmem[0] = SK_MEM_QUANTUM;
1414 	sysctl_sctp_wmem[1] = 16*1024;
1415 	sysctl_sctp_wmem[2] = max(64*1024, max_share);
1416 
1417 	/* Size and allocate the association hash table.
1418 	 * The methodology is similar to that of the tcp hash tables.
1419 	 * Though not identical.  Start by getting a goal size
1420 	 */
1421 	if (totalram_pages >= (128 * 1024))
1422 		goal = totalram_pages >> (22 - PAGE_SHIFT);
1423 	else
1424 		goal = totalram_pages >> (24 - PAGE_SHIFT);
1425 
1426 	/* Then compute the page order for said goal */
1427 	order = get_order(goal);
1428 
1429 	/* Now compute the required page order for the maximum sized table we
1430 	 * want to create
1431 	 */
1432 	max_entry_order = get_order(MAX_SCTP_PORT_HASH_ENTRIES *
1433 				    sizeof(struct sctp_bind_hashbucket));
1434 
1435 	/* Limit the page order by that maximum hash table size */
1436 	order = min(order, max_entry_order);
1437 
1438 	/* Allocate and initialize the endpoint hash table.  */
1439 	sctp_ep_hashsize = 64;
1440 	sctp_ep_hashtable =
1441 		kmalloc_array(64, sizeof(struct sctp_hashbucket), GFP_KERNEL);
1442 	if (!sctp_ep_hashtable) {
1443 		pr_err("Failed endpoint_hash alloc\n");
1444 		status = -ENOMEM;
1445 		goto err_ehash_alloc;
1446 	}
1447 	for (i = 0; i < sctp_ep_hashsize; i++) {
1448 		rwlock_init(&sctp_ep_hashtable[i].lock);
1449 		INIT_HLIST_HEAD(&sctp_ep_hashtable[i].chain);
1450 	}
1451 
1452 	/* Allocate and initialize the SCTP port hash table.
1453 	 * Note that order is initalized to start at the max sized
1454 	 * table we want to support.  If we can't get that many pages
1455 	 * reduce the order and try again
1456 	 */
1457 	do {
1458 		sctp_port_hashtable = (struct sctp_bind_hashbucket *)
1459 			__get_free_pages(GFP_KERNEL | __GFP_NOWARN, order);
1460 	} while (!sctp_port_hashtable && --order > 0);
1461 
1462 	if (!sctp_port_hashtable) {
1463 		pr_err("Failed bind hash alloc\n");
1464 		status = -ENOMEM;
1465 		goto err_bhash_alloc;
1466 	}
1467 
1468 	/* Now compute the number of entries that will fit in the
1469 	 * port hash space we allocated
1470 	 */
1471 	num_entries = (1UL << order) * PAGE_SIZE /
1472 		      sizeof(struct sctp_bind_hashbucket);
1473 
1474 	/* And finish by rounding it down to the nearest power of two
1475 	 * this wastes some memory of course, but its needed because
1476 	 * the hash function operates based on the assumption that
1477 	 * that the number of entries is a power of two
1478 	 */
1479 	sctp_port_hashsize = rounddown_pow_of_two(num_entries);
1480 
1481 	for (i = 0; i < sctp_port_hashsize; i++) {
1482 		spin_lock_init(&sctp_port_hashtable[i].lock);
1483 		INIT_HLIST_HEAD(&sctp_port_hashtable[i].chain);
1484 	}
1485 
1486 	status = sctp_transport_hashtable_init();
1487 	if (status)
1488 		goto err_thash_alloc;
1489 
1490 	pr_info("Hash tables configured (bind %d/%d)\n", sctp_port_hashsize,
1491 		num_entries);
1492 
1493 	sctp_sysctl_register();
1494 
1495 	INIT_LIST_HEAD(&sctp_address_families);
1496 	sctp_v4_pf_init();
1497 	sctp_v6_pf_init();
1498 	sctp_sched_ops_init();
1499 
1500 	status = register_pernet_subsys(&sctp_defaults_ops);
1501 	if (status)
1502 		goto err_register_defaults;
1503 
1504 	status = sctp_v4_protosw_init();
1505 	if (status)
1506 		goto err_protosw_init;
1507 
1508 	status = sctp_v6_protosw_init();
1509 	if (status)
1510 		goto err_v6_protosw_init;
1511 
1512 	status = register_pernet_subsys(&sctp_ctrlsock_ops);
1513 	if (status)
1514 		goto err_register_ctrlsock;
1515 
1516 	status = sctp_v4_add_protocol();
1517 	if (status)
1518 		goto err_add_protocol;
1519 
1520 	/* Register SCTP with inet6 layer.  */
1521 	status = sctp_v6_add_protocol();
1522 	if (status)
1523 		goto err_v6_add_protocol;
1524 
1525 	if (sctp_offload_init() < 0)
1526 		pr_crit("%s: Cannot add SCTP protocol offload\n", __func__);
1527 
1528 out:
1529 	return status;
1530 err_v6_add_protocol:
1531 	sctp_v4_del_protocol();
1532 err_add_protocol:
1533 	unregister_pernet_subsys(&sctp_ctrlsock_ops);
1534 err_register_ctrlsock:
1535 	sctp_v6_protosw_exit();
1536 err_v6_protosw_init:
1537 	sctp_v4_protosw_exit();
1538 err_protosw_init:
1539 	unregister_pernet_subsys(&sctp_defaults_ops);
1540 err_register_defaults:
1541 	sctp_v4_pf_exit();
1542 	sctp_v6_pf_exit();
1543 	sctp_sysctl_unregister();
1544 	free_pages((unsigned long)sctp_port_hashtable,
1545 		   get_order(sctp_port_hashsize *
1546 			     sizeof(struct sctp_bind_hashbucket)));
1547 err_bhash_alloc:
1548 	sctp_transport_hashtable_destroy();
1549 err_thash_alloc:
1550 	kfree(sctp_ep_hashtable);
1551 err_ehash_alloc:
1552 	percpu_counter_destroy(&sctp_sockets_allocated);
1553 err_percpu_counter_init:
1554 	kmem_cache_destroy(sctp_chunk_cachep);
1555 err_chunk_cachep:
1556 	kmem_cache_destroy(sctp_bucket_cachep);
1557 	goto out;
1558 }
1559 
1560 /* Exit handler for the SCTP protocol.  */
1561 static __exit void sctp_exit(void)
1562 {
1563 	/* BUG.  This should probably do something useful like clean
1564 	 * up all the remaining associations and all that memory.
1565 	 */
1566 
1567 	/* Unregister with inet6/inet layers. */
1568 	sctp_v6_del_protocol();
1569 	sctp_v4_del_protocol();
1570 
1571 	unregister_pernet_subsys(&sctp_ctrlsock_ops);
1572 
1573 	/* Free protosw registrations */
1574 	sctp_v6_protosw_exit();
1575 	sctp_v4_protosw_exit();
1576 
1577 	unregister_pernet_subsys(&sctp_defaults_ops);
1578 
1579 	/* Unregister with socket layer. */
1580 	sctp_v6_pf_exit();
1581 	sctp_v4_pf_exit();
1582 
1583 	sctp_sysctl_unregister();
1584 
1585 	free_pages((unsigned long)sctp_port_hashtable,
1586 		   get_order(sctp_port_hashsize *
1587 			     sizeof(struct sctp_bind_hashbucket)));
1588 	kfree(sctp_ep_hashtable);
1589 	sctp_transport_hashtable_destroy();
1590 
1591 	percpu_counter_destroy(&sctp_sockets_allocated);
1592 
1593 	rcu_barrier(); /* Wait for completion of call_rcu()'s */
1594 
1595 	kmem_cache_destroy(sctp_chunk_cachep);
1596 	kmem_cache_destroy(sctp_bucket_cachep);
1597 }
1598 
1599 module_init(sctp_init);
1600 module_exit(sctp_exit);
1601 
1602 /*
1603  * __stringify doesn't likes enums, so use IPPROTO_SCTP value (132) directly.
1604  */
1605 MODULE_ALIAS("net-pf-" __stringify(PF_INET) "-proto-132");
1606 MODULE_ALIAS("net-pf-" __stringify(PF_INET6) "-proto-132");
1607 MODULE_AUTHOR("Linux Kernel SCTP developers <linux-sctp@vger.kernel.org>");
1608 MODULE_DESCRIPTION("Support for the SCTP protocol (RFC2960)");
1609 module_param_named(no_checksums, sctp_checksum_disable, bool, 0644);
1610 MODULE_PARM_DESC(no_checksums, "Disable checksums computing and verification");
1611 MODULE_LICENSE("GPL");
1612