1// SPDX-License-Identifier: GPL-2.0-or-later
2/* SCTP kernel implementation
3 * (C) Copyright IBM Corp. 2001, 2004
4 * Copyright (c) 1999-2000 Cisco, Inc.
5 * Copyright (c) 1999-2001 Motorola, Inc.
6 * Copyright (c) 2001 Intel Corp.
7 * Copyright (c) 2001 Nokia, Inc.
8 * Copyright (c) 2001 La Monte H.P. Yarroll
9 *
10 * This file is part of the SCTP kernel implementation
11 *
12 * Initialization/cleanup for SCTP protocol support.
13 *
14 * Please send any bug reports or fixes you make to the
15 * email address(es):
16 *    lksctp developers <linux-sctp@vger.kernel.org>
17 *
18 * Written or modified by:
19 *    La Monte H.P. Yarroll <piggy@acm.org>
20 *    Karl Knutson <karl@athena.chicago.il.us>
21 *    Jon Grimm <jgrimm@us.ibm.com>
22 *    Sridhar Samudrala <sri@us.ibm.com>
23 *    Daisy Chang <daisyc@us.ibm.com>
24 *    Ardelle Fan <ardelle.fan@intel.com>
25 */
26
27#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
28
29#include <linux/module.h>
30#include <linux/init.h>
31#include <linux/netdevice.h>
32#include <linux/inetdevice.h>
33#include <linux/seq_file.h>
34#include <linux/memblock.h>
35#include <linux/highmem.h>
36#include <linux/slab.h>
37#include <net/net_namespace.h>
38#include <net/protocol.h>
39#include <net/ip.h>
40#include <net/ipv6.h>
41#include <net/route.h>
42#include <net/sctp/sctp.h>
43#include <net/addrconf.h>
44#include <net/inet_common.h>
45#include <net/inet_ecn.h>
46#include <net/udp_tunnel.h>
47
48#define MAX_SCTP_PORT_HASH_ENTRIES (64 * 1024)
49
50/* Global data structures. */
51struct sctp_globals sctp_globals __read_mostly;
52
53struct idr sctp_assocs_id;
54DEFINE_SPINLOCK(sctp_assocs_id_lock);
55
56static struct sctp_pf *sctp_pf_inet6_specific;
57static struct sctp_pf *sctp_pf_inet_specific;
58static struct sctp_af *sctp_af_v4_specific;
59static struct sctp_af *sctp_af_v6_specific;
60
61struct kmem_cache *sctp_chunk_cachep __read_mostly;
62struct kmem_cache *sctp_bucket_cachep __read_mostly;
63
64long sysctl_sctp_mem[3];
65int sysctl_sctp_rmem[3];
66int sysctl_sctp_wmem[3];
67
68/* Private helper to extract ipv4 address and stash them in
69 * the protocol structure.
70 */
71static void sctp_v4_copy_addrlist(struct list_head *addrlist,
72				  struct net_device *dev)
73{
74	struct in_device *in_dev;
75	struct in_ifaddr *ifa;
76	struct sctp_sockaddr_entry *addr;
77
78	rcu_read_lock();
79	if ((in_dev = __in_dev_get_rcu(dev)) == NULL) {
80		rcu_read_unlock();
81		return;
82	}
83
84	in_dev_for_each_ifa_rcu(ifa, in_dev) {
85		/* Add the address to the local list.  */
86		addr = kzalloc(sizeof(*addr), GFP_ATOMIC);
87		if (addr) {
88			addr->a.v4.sin_family = AF_INET;
89			addr->a.v4.sin_addr.s_addr = ifa->ifa_local;
90			addr->valid = 1;
91			INIT_LIST_HEAD(&addr->list);
92			list_add_tail(&addr->list, addrlist);
93		}
94	}
95
96	rcu_read_unlock();
97}
98
99/* Extract our IP addresses from the system and stash them in the
100 * protocol structure.
101 */
102static void sctp_get_local_addr_list(struct net *net)
103{
104	struct net_device *dev;
105	struct list_head *pos;
106	struct sctp_af *af;
107
108	rcu_read_lock();
109	for_each_netdev_rcu(net, dev) {
110		list_for_each(pos, &sctp_address_families) {
111			af = list_entry(pos, struct sctp_af, list);
112			af->copy_addrlist(&net->sctp.local_addr_list, dev);
113		}
114	}
115	rcu_read_unlock();
116}
117
118/* Free the existing local addresses.  */
119static void sctp_free_local_addr_list(struct net *net)
120{
121	struct sctp_sockaddr_entry *addr;
122	struct list_head *pos, *temp;
123
124	list_for_each_safe(pos, temp, &net->sctp.local_addr_list) {
125		addr = list_entry(pos, struct sctp_sockaddr_entry, list);
126		list_del(pos);
127		kfree(addr);
128	}
129}
130
131/* Copy the local addresses which are valid for 'scope' into 'bp'.  */
132int sctp_copy_local_addr_list(struct net *net, struct sctp_bind_addr *bp,
133			      enum sctp_scope scope, gfp_t gfp, int copy_flags)
134{
135	struct sctp_sockaddr_entry *addr;
136	union sctp_addr laddr;
137	int error = 0;
138
139	rcu_read_lock();
140	list_for_each_entry_rcu(addr, &net->sctp.local_addr_list, list) {
141		if (!addr->valid)
142			continue;
143		if (!sctp_in_scope(net, &addr->a, scope))
144			continue;
145
146		/* Now that the address is in scope, check to see if
147		 * the address type is really supported by the local
148		 * sock as well as the remote peer.
149		 */
150		if (addr->a.sa.sa_family == AF_INET &&
151		    (!(copy_flags & SCTP_ADDR4_ALLOWED) ||
152		     !(copy_flags & SCTP_ADDR4_PEERSUPP)))
153			continue;
154		if (addr->a.sa.sa_family == AF_INET6 &&
155		    (!(copy_flags & SCTP_ADDR6_ALLOWED) ||
156		     !(copy_flags & SCTP_ADDR6_PEERSUPP)))
157			continue;
158
159		laddr = addr->a;
160		/* also works for setting ipv6 address port */
161		laddr.v4.sin_port = htons(bp->port);
162		if (sctp_bind_addr_state(bp, &laddr) != -1)
163			continue;
164
165		error = sctp_add_bind_addr(bp, &addr->a, sizeof(addr->a),
166					   SCTP_ADDR_SRC, GFP_ATOMIC);
167		if (error)
168			break;
169	}
170
171	rcu_read_unlock();
172	return error;
173}
174
175/* Copy over any ip options */
176static void sctp_v4_copy_ip_options(struct sock *sk, struct sock *newsk)
177{
178	struct inet_sock *newinet, *inet = inet_sk(sk);
179	struct ip_options_rcu *inet_opt, *newopt = NULL;
180
181	newinet = inet_sk(newsk);
182
183	rcu_read_lock();
184	inet_opt = rcu_dereference(inet->inet_opt);
185	if (inet_opt) {
186		newopt = sock_kmalloc(newsk, sizeof(*inet_opt) +
187				      inet_opt->opt.optlen, GFP_ATOMIC);
188		if (newopt)
189			memcpy(newopt, inet_opt, sizeof(*inet_opt) +
190			       inet_opt->opt.optlen);
191		else
192			pr_err("%s: Failed to copy ip options\n", __func__);
193	}
194	RCU_INIT_POINTER(newinet->inet_opt, newopt);
195	rcu_read_unlock();
196}
197
198/* Account for the IP options */
199static int sctp_v4_ip_options_len(struct sock *sk)
200{
201	struct inet_sock *inet = inet_sk(sk);
202	struct ip_options_rcu *inet_opt;
203	int len = 0;
204
205	rcu_read_lock();
206	inet_opt = rcu_dereference(inet->inet_opt);
207	if (inet_opt)
208		len = inet_opt->opt.optlen;
209
210	rcu_read_unlock();
211	return len;
212}
213
214/* Initialize a sctp_addr from in incoming skb.  */
215static void sctp_v4_from_skb(union sctp_addr *addr, struct sk_buff *skb,
216			     int is_saddr)
217{
218	/* Always called on head skb, so this is safe */
219	struct sctphdr *sh = sctp_hdr(skb);
220	struct sockaddr_in *sa = &addr->v4;
221
222	addr->v4.sin_family = AF_INET;
223
224	if (is_saddr) {
225		sa->sin_port = sh->source;
226		sa->sin_addr.s_addr = ip_hdr(skb)->saddr;
227	} else {
228		sa->sin_port = sh->dest;
229		sa->sin_addr.s_addr = ip_hdr(skb)->daddr;
230	}
231	memset(sa->sin_zero, 0, sizeof(sa->sin_zero));
232}
233
234/* Initialize an sctp_addr from a socket. */
235static void sctp_v4_from_sk(union sctp_addr *addr, struct sock *sk)
236{
237	addr->v4.sin_family = AF_INET;
238	addr->v4.sin_port = 0;
239	addr->v4.sin_addr.s_addr = inet_sk(sk)->inet_rcv_saddr;
240	memset(addr->v4.sin_zero, 0, sizeof(addr->v4.sin_zero));
241}
242
243/* Initialize sk->sk_rcv_saddr from sctp_addr. */
244static void sctp_v4_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
245{
246	inet_sk(sk)->inet_rcv_saddr = addr->v4.sin_addr.s_addr;
247}
248
249/* Initialize sk->sk_daddr from sctp_addr. */
250static void sctp_v4_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
251{
252	inet_sk(sk)->inet_daddr = addr->v4.sin_addr.s_addr;
253}
254
255/* Initialize a sctp_addr from an address parameter. */
256static bool sctp_v4_from_addr_param(union sctp_addr *addr,
257				    union sctp_addr_param *param,
258				    __be16 port, int iif)
259{
260	if (ntohs(param->v4.param_hdr.length) < sizeof(struct sctp_ipv4addr_param))
261		return false;
262
263	addr->v4.sin_family = AF_INET;
264	addr->v4.sin_port = port;
265	addr->v4.sin_addr.s_addr = param->v4.addr.s_addr;
266	memset(addr->v4.sin_zero, 0, sizeof(addr->v4.sin_zero));
267
268	return true;
269}
270
271/* Initialize an address parameter from a sctp_addr and return the length
272 * of the address parameter.
273 */
274static int sctp_v4_to_addr_param(const union sctp_addr *addr,
275				 union sctp_addr_param *param)
276{
277	int length = sizeof(struct sctp_ipv4addr_param);
278
279	param->v4.param_hdr.type = SCTP_PARAM_IPV4_ADDRESS;
280	param->v4.param_hdr.length = htons(length);
281	param->v4.addr.s_addr = addr->v4.sin_addr.s_addr;
282
283	return length;
284}
285
286/* Initialize a sctp_addr from a dst_entry. */
287static void sctp_v4_dst_saddr(union sctp_addr *saddr, struct flowi4 *fl4,
288			      __be16 port)
289{
290	saddr->v4.sin_family = AF_INET;
291	saddr->v4.sin_port = port;
292	saddr->v4.sin_addr.s_addr = fl4->saddr;
293	memset(saddr->v4.sin_zero, 0, sizeof(saddr->v4.sin_zero));
294}
295
296/* Compare two addresses exactly. */
297static int sctp_v4_cmp_addr(const union sctp_addr *addr1,
298			    const union sctp_addr *addr2)
299{
300	if (addr1->sa.sa_family != addr2->sa.sa_family)
301		return 0;
302	if (addr1->v4.sin_port != addr2->v4.sin_port)
303		return 0;
304	if (addr1->v4.sin_addr.s_addr != addr2->v4.sin_addr.s_addr)
305		return 0;
306
307	return 1;
308}
309
310/* Initialize addr struct to INADDR_ANY. */
311static void sctp_v4_inaddr_any(union sctp_addr *addr, __be16 port)
312{
313	addr->v4.sin_family = AF_INET;
314	addr->v4.sin_addr.s_addr = htonl(INADDR_ANY);
315	addr->v4.sin_port = port;
316	memset(addr->v4.sin_zero, 0, sizeof(addr->v4.sin_zero));
317}
318
319/* Is this a wildcard address? */
320static int sctp_v4_is_any(const union sctp_addr *addr)
321{
322	return htonl(INADDR_ANY) == addr->v4.sin_addr.s_addr;
323}
324
325/* This function checks if the address is a valid address to be used for
326 * SCTP binding.
327 *
328 * Output:
329 * Return 0 - If the address is a non-unicast or an illegal address.
330 * Return 1 - If the address is a unicast.
331 */
332static int sctp_v4_addr_valid(union sctp_addr *addr,
333			      struct sctp_sock *sp,
334			      const struct sk_buff *skb)
335{
336	/* IPv4 addresses not allowed */
337	if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
338		return 0;
339
340	/* Is this a non-unicast address or a unusable SCTP address? */
341	if (IS_IPV4_UNUSABLE_ADDRESS(addr->v4.sin_addr.s_addr))
342		return 0;
343
344	/* Is this a broadcast address? */
345	if (skb && skb_rtable(skb)->rt_flags & RTCF_BROADCAST)
346		return 0;
347
348	return 1;
349}
350
351/* Should this be available for binding?   */
352static int sctp_v4_available(union sctp_addr *addr, struct sctp_sock *sp)
353{
354	struct sock *sk = &sp->inet.sk;
355	struct net *net = sock_net(sk);
356	int tb_id = RT_TABLE_LOCAL;
357	int ret;
358
359	tb_id = l3mdev_fib_table_by_index(net, sk->sk_bound_dev_if) ?: tb_id;
360	ret = inet_addr_type_table(net, addr->v4.sin_addr.s_addr, tb_id);
361	if (addr->v4.sin_addr.s_addr != htonl(INADDR_ANY) &&
362	   ret != RTN_LOCAL &&
363	   !inet_test_bit(FREEBIND, sk) &&
364	    !READ_ONCE(net->ipv4.sysctl_ip_nonlocal_bind))
365		return 0;
366
367	if (ipv6_only_sock(sctp_opt2sk(sp)))
368		return 0;
369
370	return 1;
371}
372
373/* Checking the loopback, private and other address scopes as defined in
374 * RFC 1918.   The IPv4 scoping is based on the draft for SCTP IPv4
375 * scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>.
376 *
377 * Level 0 - unusable SCTP addresses
378 * Level 1 - loopback address
379 * Level 2 - link-local addresses
380 * Level 3 - private addresses.
381 * Level 4 - global addresses
382 * For INIT and INIT-ACK address list, let L be the level of
383 * requested destination address, sender and receiver
384 * SHOULD include all of its addresses with level greater
385 * than or equal to L.
386 *
387 * IPv4 scoping can be controlled through sysctl option
388 * net.sctp.addr_scope_policy
389 */
390static enum sctp_scope sctp_v4_scope(union sctp_addr *addr)
391{
392	enum sctp_scope retval;
393
394	/* Check for unusable SCTP addresses. */
395	if (IS_IPV4_UNUSABLE_ADDRESS(addr->v4.sin_addr.s_addr)) {
396		retval =  SCTP_SCOPE_UNUSABLE;
397	} else if (ipv4_is_loopback(addr->v4.sin_addr.s_addr)) {
398		retval = SCTP_SCOPE_LOOPBACK;
399	} else if (ipv4_is_linklocal_169(addr->v4.sin_addr.s_addr)) {
400		retval = SCTP_SCOPE_LINK;
401	} else if (ipv4_is_private_10(addr->v4.sin_addr.s_addr) ||
402		   ipv4_is_private_172(addr->v4.sin_addr.s_addr) ||
403		   ipv4_is_private_192(addr->v4.sin_addr.s_addr) ||
404		   ipv4_is_test_198(addr->v4.sin_addr.s_addr)) {
405		retval = SCTP_SCOPE_PRIVATE;
406	} else {
407		retval = SCTP_SCOPE_GLOBAL;
408	}
409
410	return retval;
411}
412
413/* Returns a valid dst cache entry for the given source and destination ip
414 * addresses. If an association is passed, trys to get a dst entry with a
415 * source address that matches an address in the bind address list.
416 */
417static void sctp_v4_get_dst(struct sctp_transport *t, union sctp_addr *saddr,
418				struct flowi *fl, struct sock *sk)
419{
420	struct sctp_association *asoc = t->asoc;
421	struct rtable *rt;
422	struct flowi _fl;
423	struct flowi4 *fl4 = &_fl.u.ip4;
424	struct sctp_bind_addr *bp;
425	struct sctp_sockaddr_entry *laddr;
426	struct dst_entry *dst = NULL;
427	union sctp_addr *daddr = &t->ipaddr;
428	union sctp_addr dst_saddr;
429	u8 tos = READ_ONCE(inet_sk(sk)->tos);
430
431	if (t->dscp & SCTP_DSCP_SET_MASK)
432		tos = t->dscp & SCTP_DSCP_VAL_MASK;
433	memset(&_fl, 0x0, sizeof(_fl));
434	fl4->daddr  = daddr->v4.sin_addr.s_addr;
435	fl4->fl4_dport = daddr->v4.sin_port;
436	fl4->flowi4_proto = IPPROTO_SCTP;
437	if (asoc) {
438		fl4->flowi4_tos = RT_TOS(tos);
439		fl4->flowi4_scope = ip_sock_rt_scope(asoc->base.sk);
440		fl4->flowi4_oif = asoc->base.sk->sk_bound_dev_if;
441		fl4->fl4_sport = htons(asoc->base.bind_addr.port);
442	}
443	if (saddr) {
444		fl4->saddr = saddr->v4.sin_addr.s_addr;
445		if (!fl4->fl4_sport)
446			fl4->fl4_sport = saddr->v4.sin_port;
447	}
448
449	pr_debug("%s: dst:%pI4, src:%pI4 - ", __func__, &fl4->daddr,
450		 &fl4->saddr);
451
452	rt = ip_route_output_key(sock_net(sk), fl4);
453	if (!IS_ERR(rt)) {
454		dst = &rt->dst;
455		t->dst = dst;
456		memcpy(fl, &_fl, sizeof(_fl));
457	}
458
459	/* If there is no association or if a source address is passed, no
460	 * more validation is required.
461	 */
462	if (!asoc || saddr)
463		goto out;
464
465	bp = &asoc->base.bind_addr;
466
467	if (dst) {
468		/* Walk through the bind address list and look for a bind
469		 * address that matches the source address of the returned dst.
470		 */
471		sctp_v4_dst_saddr(&dst_saddr, fl4, htons(bp->port));
472		rcu_read_lock();
473		list_for_each_entry_rcu(laddr, &bp->address_list, list) {
474			if (!laddr->valid || (laddr->state == SCTP_ADDR_DEL) ||
475			    (laddr->state != SCTP_ADDR_SRC &&
476			    !asoc->src_out_of_asoc_ok))
477				continue;
478			if (sctp_v4_cmp_addr(&dst_saddr, &laddr->a))
479				goto out_unlock;
480		}
481		rcu_read_unlock();
482
483		/* None of the bound addresses match the source address of the
484		 * dst. So release it.
485		 */
486		dst_release(dst);
487		dst = NULL;
488	}
489
490	/* Walk through the bind address list and try to get a dst that
491	 * matches a bind address as the source address.
492	 */
493	rcu_read_lock();
494	list_for_each_entry_rcu(laddr, &bp->address_list, list) {
495		struct net_device *odev;
496
497		if (!laddr->valid)
498			continue;
499		if (laddr->state != SCTP_ADDR_SRC ||
500		    AF_INET != laddr->a.sa.sa_family)
501			continue;
502
503		fl4->fl4_sport = laddr->a.v4.sin_port;
504		flowi4_update_output(fl4, asoc->base.sk->sk_bound_dev_if,
505				     daddr->v4.sin_addr.s_addr,
506				     laddr->a.v4.sin_addr.s_addr);
507
508		rt = ip_route_output_key(sock_net(sk), fl4);
509		if (IS_ERR(rt))
510			continue;
511
512		/* Ensure the src address belongs to the output
513		 * interface.
514		 */
515		odev = __ip_dev_find(sock_net(sk), laddr->a.v4.sin_addr.s_addr,
516				     false);
517		if (!odev || odev->ifindex != fl4->flowi4_oif) {
518			if (!dst) {
519				dst = &rt->dst;
520				t->dst = dst;
521				memcpy(fl, &_fl, sizeof(_fl));
522			} else {
523				dst_release(&rt->dst);
524			}
525			continue;
526		}
527
528		dst_release(dst);
529		dst = &rt->dst;
530		t->dst = dst;
531		memcpy(fl, &_fl, sizeof(_fl));
532		break;
533	}
534
535out_unlock:
536	rcu_read_unlock();
537out:
538	if (dst) {
539		pr_debug("rt_dst:%pI4, rt_src:%pI4\n",
540			 &fl->u.ip4.daddr, &fl->u.ip4.saddr);
541	} else {
542		t->dst = NULL;
543		pr_debug("no route\n");
544	}
545}
546
547/* For v4, the source address is cached in the route entry(dst). So no need
548 * to cache it separately and hence this is an empty routine.
549 */
550static void sctp_v4_get_saddr(struct sctp_sock *sk,
551			      struct sctp_transport *t,
552			      struct flowi *fl)
553{
554	union sctp_addr *saddr = &t->saddr;
555	struct rtable *rt = (struct rtable *)t->dst;
556
557	if (rt) {
558		saddr->v4.sin_family = AF_INET;
559		saddr->v4.sin_addr.s_addr = fl->u.ip4.saddr;
560	}
561}
562
563/* What interface did this skb arrive on? */
564static int sctp_v4_skb_iif(const struct sk_buff *skb)
565{
566	return inet_iif(skb);
567}
568
569static int sctp_v4_skb_sdif(const struct sk_buff *skb)
570{
571	return inet_sdif(skb);
572}
573
574/* Was this packet marked by Explicit Congestion Notification? */
575static int sctp_v4_is_ce(const struct sk_buff *skb)
576{
577	return INET_ECN_is_ce(ip_hdr(skb)->tos);
578}
579
580/* Create and initialize a new sk for the socket returned by accept(). */
581static struct sock *sctp_v4_create_accept_sk(struct sock *sk,
582					     struct sctp_association *asoc,
583					     bool kern)
584{
585	struct sock *newsk = sk_alloc(sock_net(sk), PF_INET, GFP_KERNEL,
586			sk->sk_prot, kern);
587	struct inet_sock *newinet;
588
589	if (!newsk)
590		goto out;
591
592	sock_init_data(NULL, newsk);
593
594	sctp_copy_sock(newsk, sk, asoc);
595	sock_reset_flag(newsk, SOCK_ZAPPED);
596
597	sctp_v4_copy_ip_options(sk, newsk);
598
599	newinet = inet_sk(newsk);
600
601	newinet->inet_daddr = asoc->peer.primary_addr.v4.sin_addr.s_addr;
602
603	if (newsk->sk_prot->init(newsk)) {
604		sk_common_release(newsk);
605		newsk = NULL;
606	}
607
608out:
609	return newsk;
610}
611
612static int sctp_v4_addr_to_user(struct sctp_sock *sp, union sctp_addr *addr)
613{
614	/* No address mapping for V4 sockets */
615	memset(addr->v4.sin_zero, 0, sizeof(addr->v4.sin_zero));
616	return sizeof(struct sockaddr_in);
617}
618
619/* Dump the v4 addr to the seq file. */
620static void sctp_v4_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
621{
622	seq_printf(seq, "%pI4 ", &addr->v4.sin_addr);
623}
624
625static void sctp_v4_ecn_capable(struct sock *sk)
626{
627	INET_ECN_xmit(sk);
628}
629
630static void sctp_addr_wq_timeout_handler(struct timer_list *t)
631{
632	struct net *net = from_timer(net, t, sctp.addr_wq_timer);
633	struct sctp_sockaddr_entry *addrw, *temp;
634	struct sctp_sock *sp;
635
636	spin_lock_bh(&net->sctp.addr_wq_lock);
637
638	list_for_each_entry_safe(addrw, temp, &net->sctp.addr_waitq, list) {
639		pr_debug("%s: the first ent in wq:%p is addr:%pISc for cmd:%d at "
640			 "entry:%p\n", __func__, &net->sctp.addr_waitq, &addrw->a.sa,
641			 addrw->state, addrw);
642
643#if IS_ENABLED(CONFIG_IPV6)
644		/* Now we send an ASCONF for each association */
645		/* Note. we currently don't handle link local IPv6 addressees */
646		if (addrw->a.sa.sa_family == AF_INET6) {
647			struct in6_addr *in6;
648
649			if (ipv6_addr_type(&addrw->a.v6.sin6_addr) &
650			    IPV6_ADDR_LINKLOCAL)
651				goto free_next;
652
653			in6 = (struct in6_addr *)&addrw->a.v6.sin6_addr;
654			if (ipv6_chk_addr(net, in6, NULL, 0) == 0 &&
655			    addrw->state == SCTP_ADDR_NEW) {
656				unsigned long timeo_val;
657
658				pr_debug("%s: this is on DAD, trying %d sec "
659					 "later\n", __func__,
660					 SCTP_ADDRESS_TICK_DELAY);
661
662				timeo_val = jiffies;
663				timeo_val += msecs_to_jiffies(SCTP_ADDRESS_TICK_DELAY);
664				mod_timer(&net->sctp.addr_wq_timer, timeo_val);
665				break;
666			}
667		}
668#endif
669		list_for_each_entry(sp, &net->sctp.auto_asconf_splist, auto_asconf_list) {
670			struct sock *sk;
671
672			sk = sctp_opt2sk(sp);
673			/* ignore bound-specific endpoints */
674			if (!sctp_is_ep_boundall(sk))
675				continue;
676			bh_lock_sock(sk);
677			if (sctp_asconf_mgmt(sp, addrw) < 0)
678				pr_debug("%s: sctp_asconf_mgmt failed\n", __func__);
679			bh_unlock_sock(sk);
680		}
681#if IS_ENABLED(CONFIG_IPV6)
682free_next:
683#endif
684		list_del(&addrw->list);
685		kfree(addrw);
686	}
687	spin_unlock_bh(&net->sctp.addr_wq_lock);
688}
689
690static void sctp_free_addr_wq(struct net *net)
691{
692	struct sctp_sockaddr_entry *addrw;
693	struct sctp_sockaddr_entry *temp;
694
695	spin_lock_bh(&net->sctp.addr_wq_lock);
696	del_timer(&net->sctp.addr_wq_timer);
697	list_for_each_entry_safe(addrw, temp, &net->sctp.addr_waitq, list) {
698		list_del(&addrw->list);
699		kfree(addrw);
700	}
701	spin_unlock_bh(&net->sctp.addr_wq_lock);
702}
703
704/* lookup the entry for the same address in the addr_waitq
705 * sctp_addr_wq MUST be locked
706 */
707static struct sctp_sockaddr_entry *sctp_addr_wq_lookup(struct net *net,
708					struct sctp_sockaddr_entry *addr)
709{
710	struct sctp_sockaddr_entry *addrw;
711
712	list_for_each_entry(addrw, &net->sctp.addr_waitq, list) {
713		if (addrw->a.sa.sa_family != addr->a.sa.sa_family)
714			continue;
715		if (addrw->a.sa.sa_family == AF_INET) {
716			if (addrw->a.v4.sin_addr.s_addr ==
717			    addr->a.v4.sin_addr.s_addr)
718				return addrw;
719		} else if (addrw->a.sa.sa_family == AF_INET6) {
720			if (ipv6_addr_equal(&addrw->a.v6.sin6_addr,
721			    &addr->a.v6.sin6_addr))
722				return addrw;
723		}
724	}
725	return NULL;
726}
727
728void sctp_addr_wq_mgmt(struct net *net, struct sctp_sockaddr_entry *addr, int cmd)
729{
730	struct sctp_sockaddr_entry *addrw;
731	unsigned long timeo_val;
732
733	/* first, we check if an opposite message already exist in the queue.
734	 * If we found such message, it is removed.
735	 * This operation is a bit stupid, but the DHCP client attaches the
736	 * new address after a couple of addition and deletion of that address
737	 */
738
739	spin_lock_bh(&net->sctp.addr_wq_lock);
740	/* Offsets existing events in addr_wq */
741	addrw = sctp_addr_wq_lookup(net, addr);
742	if (addrw) {
743		if (addrw->state != cmd) {
744			pr_debug("%s: offsets existing entry for %d, addr:%pISc "
745				 "in wq:%p\n", __func__, addrw->state, &addrw->a.sa,
746				 &net->sctp.addr_waitq);
747
748			list_del(&addrw->list);
749			kfree(addrw);
750		}
751		spin_unlock_bh(&net->sctp.addr_wq_lock);
752		return;
753	}
754
755	/* OK, we have to add the new address to the wait queue */
756	addrw = kmemdup(addr, sizeof(struct sctp_sockaddr_entry), GFP_ATOMIC);
757	if (addrw == NULL) {
758		spin_unlock_bh(&net->sctp.addr_wq_lock);
759		return;
760	}
761	addrw->state = cmd;
762	list_add_tail(&addrw->list, &net->sctp.addr_waitq);
763
764	pr_debug("%s: add new entry for cmd:%d, addr:%pISc in wq:%p\n",
765		 __func__, addrw->state, &addrw->a.sa, &net->sctp.addr_waitq);
766
767	if (!timer_pending(&net->sctp.addr_wq_timer)) {
768		timeo_val = jiffies;
769		timeo_val += msecs_to_jiffies(SCTP_ADDRESS_TICK_DELAY);
770		mod_timer(&net->sctp.addr_wq_timer, timeo_val);
771	}
772	spin_unlock_bh(&net->sctp.addr_wq_lock);
773}
774
775/* Event handler for inet address addition/deletion events.
776 * The sctp_local_addr_list needs to be protocted by a spin lock since
777 * multiple notifiers (say IPv4 and IPv6) may be running at the same
778 * time and thus corrupt the list.
779 * The reader side is protected with RCU.
780 */
781static int sctp_inetaddr_event(struct notifier_block *this, unsigned long ev,
782			       void *ptr)
783{
784	struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
785	struct sctp_sockaddr_entry *addr = NULL;
786	struct sctp_sockaddr_entry *temp;
787	struct net *net = dev_net(ifa->ifa_dev->dev);
788	int found = 0;
789
790	switch (ev) {
791	case NETDEV_UP:
792		addr = kzalloc(sizeof(*addr), GFP_ATOMIC);
793		if (addr) {
794			addr->a.v4.sin_family = AF_INET;
795			addr->a.v4.sin_addr.s_addr = ifa->ifa_local;
796			addr->valid = 1;
797			spin_lock_bh(&net->sctp.local_addr_lock);
798			list_add_tail_rcu(&addr->list, &net->sctp.local_addr_list);
799			sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_NEW);
800			spin_unlock_bh(&net->sctp.local_addr_lock);
801		}
802		break;
803	case NETDEV_DOWN:
804		spin_lock_bh(&net->sctp.local_addr_lock);
805		list_for_each_entry_safe(addr, temp,
806					&net->sctp.local_addr_list, list) {
807			if (addr->a.sa.sa_family == AF_INET &&
808					addr->a.v4.sin_addr.s_addr ==
809					ifa->ifa_local) {
810				sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_DEL);
811				found = 1;
812				addr->valid = 0;
813				list_del_rcu(&addr->list);
814				break;
815			}
816		}
817		spin_unlock_bh(&net->sctp.local_addr_lock);
818		if (found)
819			kfree_rcu(addr, rcu);
820		break;
821	}
822
823	return NOTIFY_DONE;
824}
825
826/*
827 * Initialize the control inode/socket with a control endpoint data
828 * structure.  This endpoint is reserved exclusively for the OOTB processing.
829 */
830static int sctp_ctl_sock_init(struct net *net)
831{
832	int err;
833	sa_family_t family = PF_INET;
834
835	if (sctp_get_pf_specific(PF_INET6))
836		family = PF_INET6;
837
838	err = inet_ctl_sock_create(&net->sctp.ctl_sock, family,
839				   SOCK_SEQPACKET, IPPROTO_SCTP, net);
840
841	/* If IPv6 socket could not be created, try the IPv4 socket */
842	if (err < 0 && family == PF_INET6)
843		err = inet_ctl_sock_create(&net->sctp.ctl_sock, AF_INET,
844					   SOCK_SEQPACKET, IPPROTO_SCTP,
845					   net);
846
847	if (err < 0) {
848		pr_err("Failed to create the SCTP control socket\n");
849		return err;
850	}
851	return 0;
852}
853
854static int sctp_udp_rcv(struct sock *sk, struct sk_buff *skb)
855{
856	SCTP_INPUT_CB(skb)->encap_port = udp_hdr(skb)->source;
857
858	skb_set_transport_header(skb, sizeof(struct udphdr));
859	sctp_rcv(skb);
860	return 0;
861}
862
863int sctp_udp_sock_start(struct net *net)
864{
865	struct udp_tunnel_sock_cfg tuncfg = {NULL};
866	struct udp_port_cfg udp_conf = {0};
867	struct socket *sock;
868	int err;
869
870	udp_conf.family = AF_INET;
871	udp_conf.local_ip.s_addr = htonl(INADDR_ANY);
872	udp_conf.local_udp_port = htons(net->sctp.udp_port);
873	err = udp_sock_create(net, &udp_conf, &sock);
874	if (err) {
875		pr_err("Failed to create the SCTP UDP tunneling v4 sock\n");
876		return err;
877	}
878
879	tuncfg.encap_type = 1;
880	tuncfg.encap_rcv = sctp_udp_rcv;
881	tuncfg.encap_err_lookup = sctp_udp_v4_err;
882	setup_udp_tunnel_sock(net, sock, &tuncfg);
883	net->sctp.udp4_sock = sock->sk;
884
885#if IS_ENABLED(CONFIG_IPV6)
886	memset(&udp_conf, 0, sizeof(udp_conf));
887
888	udp_conf.family = AF_INET6;
889	udp_conf.local_ip6 = in6addr_any;
890	udp_conf.local_udp_port = htons(net->sctp.udp_port);
891	udp_conf.use_udp6_rx_checksums = true;
892	udp_conf.ipv6_v6only = true;
893	err = udp_sock_create(net, &udp_conf, &sock);
894	if (err) {
895		pr_err("Failed to create the SCTP UDP tunneling v6 sock\n");
896		udp_tunnel_sock_release(net->sctp.udp4_sock->sk_socket);
897		net->sctp.udp4_sock = NULL;
898		return err;
899	}
900
901	tuncfg.encap_type = 1;
902	tuncfg.encap_rcv = sctp_udp_rcv;
903	tuncfg.encap_err_lookup = sctp_udp_v6_err;
904	setup_udp_tunnel_sock(net, sock, &tuncfg);
905	net->sctp.udp6_sock = sock->sk;
906#endif
907
908	return 0;
909}
910
911void sctp_udp_sock_stop(struct net *net)
912{
913	if (net->sctp.udp4_sock) {
914		udp_tunnel_sock_release(net->sctp.udp4_sock->sk_socket);
915		net->sctp.udp4_sock = NULL;
916	}
917	if (net->sctp.udp6_sock) {
918		udp_tunnel_sock_release(net->sctp.udp6_sock->sk_socket);
919		net->sctp.udp6_sock = NULL;
920	}
921}
922
923/* Register address family specific functions. */
924int sctp_register_af(struct sctp_af *af)
925{
926	switch (af->sa_family) {
927	case AF_INET:
928		if (sctp_af_v4_specific)
929			return 0;
930		sctp_af_v4_specific = af;
931		break;
932	case AF_INET6:
933		if (sctp_af_v6_specific)
934			return 0;
935		sctp_af_v6_specific = af;
936		break;
937	default:
938		return 0;
939	}
940
941	INIT_LIST_HEAD(&af->list);
942	list_add_tail(&af->list, &sctp_address_families);
943	return 1;
944}
945
946/* Get the table of functions for manipulating a particular address
947 * family.
948 */
949struct sctp_af *sctp_get_af_specific(sa_family_t family)
950{
951	switch (family) {
952	case AF_INET:
953		return sctp_af_v4_specific;
954	case AF_INET6:
955		return sctp_af_v6_specific;
956	default:
957		return NULL;
958	}
959}
960
961/* Common code to initialize a AF_INET msg_name. */
962static void sctp_inet_msgname(char *msgname, int *addr_len)
963{
964	struct sockaddr_in *sin;
965
966	sin = (struct sockaddr_in *)msgname;
967	*addr_len = sizeof(struct sockaddr_in);
968	sin->sin_family = AF_INET;
969	memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
970}
971
972/* Copy the primary address of the peer primary address as the msg_name. */
973static void sctp_inet_event_msgname(struct sctp_ulpevent *event, char *msgname,
974				    int *addr_len)
975{
976	struct sockaddr_in *sin, *sinfrom;
977
978	if (msgname) {
979		struct sctp_association *asoc;
980
981		asoc = event->asoc;
982		sctp_inet_msgname(msgname, addr_len);
983		sin = (struct sockaddr_in *)msgname;
984		sinfrom = &asoc->peer.primary_addr.v4;
985		sin->sin_port = htons(asoc->peer.port);
986		sin->sin_addr.s_addr = sinfrom->sin_addr.s_addr;
987	}
988}
989
990/* Initialize and copy out a msgname from an inbound skb. */
991static void sctp_inet_skb_msgname(struct sk_buff *skb, char *msgname, int *len)
992{
993	if (msgname) {
994		struct sctphdr *sh = sctp_hdr(skb);
995		struct sockaddr_in *sin = (struct sockaddr_in *)msgname;
996
997		sctp_inet_msgname(msgname, len);
998		sin->sin_port = sh->source;
999		sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
1000	}
1001}
1002
1003/* Do we support this AF? */
1004static int sctp_inet_af_supported(sa_family_t family, struct sctp_sock *sp)
1005{
1006	/* PF_INET only supports AF_INET addresses. */
1007	return AF_INET == family;
1008}
1009
1010/* Address matching with wildcards allowed. */
1011static int sctp_inet_cmp_addr(const union sctp_addr *addr1,
1012			      const union sctp_addr *addr2,
1013			      struct sctp_sock *opt)
1014{
1015	/* PF_INET only supports AF_INET addresses. */
1016	if (addr1->sa.sa_family != addr2->sa.sa_family)
1017		return 0;
1018	if (htonl(INADDR_ANY) == addr1->v4.sin_addr.s_addr ||
1019	    htonl(INADDR_ANY) == addr2->v4.sin_addr.s_addr)
1020		return 1;
1021	if (addr1->v4.sin_addr.s_addr == addr2->v4.sin_addr.s_addr)
1022		return 1;
1023
1024	return 0;
1025}
1026
1027/* Verify that provided sockaddr looks bindable.  Common verification has
1028 * already been taken care of.
1029 */
1030static int sctp_inet_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
1031{
1032	return sctp_v4_available(addr, opt);
1033}
1034
1035/* Verify that sockaddr looks sendable.  Common verification has already
1036 * been taken care of.
1037 */
1038static int sctp_inet_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
1039{
1040	return 1;
1041}
1042
1043/* Fill in Supported Address Type information for INIT and INIT-ACK
1044 * chunks.  Returns number of addresses supported.
1045 */
1046static int sctp_inet_supported_addrs(const struct sctp_sock *opt,
1047				     __be16 *types)
1048{
1049	types[0] = SCTP_PARAM_IPV4_ADDRESS;
1050	return 1;
1051}
1052
1053/* Wrapper routine that calls the ip transmit routine. */
1054static inline int sctp_v4_xmit(struct sk_buff *skb, struct sctp_transport *t)
1055{
1056	struct dst_entry *dst = dst_clone(t->dst);
1057	struct flowi4 *fl4 = &t->fl.u.ip4;
1058	struct sock *sk = skb->sk;
1059	struct inet_sock *inet = inet_sk(sk);
1060	__u8 dscp = READ_ONCE(inet->tos);
1061	__be16 df = 0;
1062
1063	pr_debug("%s: skb:%p, len:%d, src:%pI4, dst:%pI4\n", __func__, skb,
1064		 skb->len, &fl4->saddr, &fl4->daddr);
1065
1066	if (t->dscp & SCTP_DSCP_SET_MASK)
1067		dscp = t->dscp & SCTP_DSCP_VAL_MASK;
1068
1069	inet->pmtudisc = t->param_flags & SPP_PMTUD_ENABLE ? IP_PMTUDISC_DO
1070							   : IP_PMTUDISC_DONT;
1071	SCTP_INC_STATS(sock_net(sk), SCTP_MIB_OUTSCTPPACKS);
1072
1073	if (!t->encap_port || !sctp_sk(sk)->udp_port) {
1074		skb_dst_set(skb, dst);
1075		return __ip_queue_xmit(sk, skb, &t->fl, dscp);
1076	}
1077
1078	if (skb_is_gso(skb))
1079		skb_shinfo(skb)->gso_type |= SKB_GSO_UDP_TUNNEL_CSUM;
1080
1081	if (ip_dont_fragment(sk, dst) && !skb->ignore_df)
1082		df = htons(IP_DF);
1083
1084	skb->encapsulation = 1;
1085	skb_reset_inner_mac_header(skb);
1086	skb_reset_inner_transport_header(skb);
1087	skb_set_inner_ipproto(skb, IPPROTO_SCTP);
1088	udp_tunnel_xmit_skb((struct rtable *)dst, sk, skb, fl4->saddr,
1089			    fl4->daddr, dscp, ip4_dst_hoplimit(dst), df,
1090			    sctp_sk(sk)->udp_port, t->encap_port, false, false);
1091	return 0;
1092}
1093
1094static struct sctp_af sctp_af_inet;
1095
1096static struct sctp_pf sctp_pf_inet = {
1097	.event_msgname = sctp_inet_event_msgname,
1098	.skb_msgname   = sctp_inet_skb_msgname,
1099	.af_supported  = sctp_inet_af_supported,
1100	.cmp_addr      = sctp_inet_cmp_addr,
1101	.bind_verify   = sctp_inet_bind_verify,
1102	.send_verify   = sctp_inet_send_verify,
1103	.supported_addrs = sctp_inet_supported_addrs,
1104	.create_accept_sk = sctp_v4_create_accept_sk,
1105	.addr_to_user  = sctp_v4_addr_to_user,
1106	.to_sk_saddr   = sctp_v4_to_sk_saddr,
1107	.to_sk_daddr   = sctp_v4_to_sk_daddr,
1108	.copy_ip_options = sctp_v4_copy_ip_options,
1109	.af            = &sctp_af_inet
1110};
1111
1112/* Notifier for inetaddr addition/deletion events.  */
1113static struct notifier_block sctp_inetaddr_notifier = {
1114	.notifier_call = sctp_inetaddr_event,
1115};
1116
1117/* Socket operations.  */
1118static const struct proto_ops inet_seqpacket_ops = {
1119	.family		   = PF_INET,
1120	.owner		   = THIS_MODULE,
1121	.release	   = inet_release,	/* Needs to be wrapped... */
1122	.bind		   = inet_bind,
1123	.connect	   = sctp_inet_connect,
1124	.socketpair	   = sock_no_socketpair,
1125	.accept		   = inet_accept,
1126	.getname	   = inet_getname,	/* Semantics are different.  */
1127	.poll		   = sctp_poll,
1128	.ioctl		   = inet_ioctl,
1129	.gettstamp	   = sock_gettstamp,
1130	.listen		   = sctp_inet_listen,
1131	.shutdown	   = inet_shutdown,	/* Looks harmless.  */
1132	.setsockopt	   = sock_common_setsockopt, /* IP_SOL IP_OPTION is a problem */
1133	.getsockopt	   = sock_common_getsockopt,
1134	.sendmsg	   = inet_sendmsg,
1135	.recvmsg	   = inet_recvmsg,
1136	.mmap		   = sock_no_mmap,
1137};
1138
1139/* Registration with AF_INET family.  */
1140static struct inet_protosw sctp_seqpacket_protosw = {
1141	.type       = SOCK_SEQPACKET,
1142	.protocol   = IPPROTO_SCTP,
1143	.prot       = &sctp_prot,
1144	.ops        = &inet_seqpacket_ops,
1145	.flags      = SCTP_PROTOSW_FLAG
1146};
1147static struct inet_protosw sctp_stream_protosw = {
1148	.type       = SOCK_STREAM,
1149	.protocol   = IPPROTO_SCTP,
1150	.prot       = &sctp_prot,
1151	.ops        = &inet_seqpacket_ops,
1152	.flags      = SCTP_PROTOSW_FLAG
1153};
1154
1155static int sctp4_rcv(struct sk_buff *skb)
1156{
1157	SCTP_INPUT_CB(skb)->encap_port = 0;
1158	return sctp_rcv(skb);
1159}
1160
1161/* Register with IP layer.  */
1162static const struct net_protocol sctp_protocol = {
1163	.handler     = sctp4_rcv,
1164	.err_handler = sctp_v4_err,
1165	.no_policy   = 1,
1166	.icmp_strict_tag_validation = 1,
1167};
1168
1169/* IPv4 address related functions.  */
1170static struct sctp_af sctp_af_inet = {
1171	.sa_family	   = AF_INET,
1172	.sctp_xmit	   = sctp_v4_xmit,
1173	.setsockopt	   = ip_setsockopt,
1174	.getsockopt	   = ip_getsockopt,
1175	.get_dst	   = sctp_v4_get_dst,
1176	.get_saddr	   = sctp_v4_get_saddr,
1177	.copy_addrlist	   = sctp_v4_copy_addrlist,
1178	.from_skb	   = sctp_v4_from_skb,
1179	.from_sk	   = sctp_v4_from_sk,
1180	.from_addr_param   = sctp_v4_from_addr_param,
1181	.to_addr_param	   = sctp_v4_to_addr_param,
1182	.cmp_addr	   = sctp_v4_cmp_addr,
1183	.addr_valid	   = sctp_v4_addr_valid,
1184	.inaddr_any	   = sctp_v4_inaddr_any,
1185	.is_any		   = sctp_v4_is_any,
1186	.available	   = sctp_v4_available,
1187	.scope		   = sctp_v4_scope,
1188	.skb_iif	   = sctp_v4_skb_iif,
1189	.skb_sdif	   = sctp_v4_skb_sdif,
1190	.is_ce		   = sctp_v4_is_ce,
1191	.seq_dump_addr	   = sctp_v4_seq_dump_addr,
1192	.ecn_capable	   = sctp_v4_ecn_capable,
1193	.net_header_len	   = sizeof(struct iphdr),
1194	.sockaddr_len	   = sizeof(struct sockaddr_in),
1195	.ip_options_len	   = sctp_v4_ip_options_len,
1196};
1197
1198struct sctp_pf *sctp_get_pf_specific(sa_family_t family)
1199{
1200	switch (family) {
1201	case PF_INET:
1202		return sctp_pf_inet_specific;
1203	case PF_INET6:
1204		return sctp_pf_inet6_specific;
1205	default:
1206		return NULL;
1207	}
1208}
1209
1210/* Register the PF specific function table.  */
1211int sctp_register_pf(struct sctp_pf *pf, sa_family_t family)
1212{
1213	switch (family) {
1214	case PF_INET:
1215		if (sctp_pf_inet_specific)
1216			return 0;
1217		sctp_pf_inet_specific = pf;
1218		break;
1219	case PF_INET6:
1220		if (sctp_pf_inet6_specific)
1221			return 0;
1222		sctp_pf_inet6_specific = pf;
1223		break;
1224	default:
1225		return 0;
1226	}
1227	return 1;
1228}
1229
1230static inline int init_sctp_mibs(struct net *net)
1231{
1232	net->sctp.sctp_statistics = alloc_percpu(struct sctp_mib);
1233	if (!net->sctp.sctp_statistics)
1234		return -ENOMEM;
1235	return 0;
1236}
1237
1238static inline void cleanup_sctp_mibs(struct net *net)
1239{
1240	free_percpu(net->sctp.sctp_statistics);
1241}
1242
1243static void sctp_v4_pf_init(void)
1244{
1245	/* Initialize the SCTP specific PF functions. */
1246	sctp_register_pf(&sctp_pf_inet, PF_INET);
1247	sctp_register_af(&sctp_af_inet);
1248}
1249
1250static void sctp_v4_pf_exit(void)
1251{
1252	list_del(&sctp_af_inet.list);
1253}
1254
1255static int sctp_v4_protosw_init(void)
1256{
1257	int rc;
1258
1259	rc = proto_register(&sctp_prot, 1);
1260	if (rc)
1261		return rc;
1262
1263	/* Register SCTP(UDP and TCP style) with socket layer.  */
1264	inet_register_protosw(&sctp_seqpacket_protosw);
1265	inet_register_protosw(&sctp_stream_protosw);
1266
1267	return 0;
1268}
1269
1270static void sctp_v4_protosw_exit(void)
1271{
1272	inet_unregister_protosw(&sctp_stream_protosw);
1273	inet_unregister_protosw(&sctp_seqpacket_protosw);
1274	proto_unregister(&sctp_prot);
1275}
1276
1277static int sctp_v4_add_protocol(void)
1278{
1279	/* Register notifier for inet address additions/deletions. */
1280	register_inetaddr_notifier(&sctp_inetaddr_notifier);
1281
1282	/* Register SCTP with inet layer.  */
1283	if (inet_add_protocol(&sctp_protocol, IPPROTO_SCTP) < 0)
1284		return -EAGAIN;
1285
1286	return 0;
1287}
1288
1289static void sctp_v4_del_protocol(void)
1290{
1291	inet_del_protocol(&sctp_protocol, IPPROTO_SCTP);
1292	unregister_inetaddr_notifier(&sctp_inetaddr_notifier);
1293}
1294
1295static int __net_init sctp_defaults_init(struct net *net)
1296{
1297	int status;
1298
1299	/*
1300	 * 14. Suggested SCTP Protocol Parameter Values
1301	 */
1302	/* The following protocol parameters are RECOMMENDED:  */
1303	/* RTO.Initial              - 3  seconds */
1304	net->sctp.rto_initial			= SCTP_RTO_INITIAL;
1305	/* RTO.Min                  - 1  second */
1306	net->sctp.rto_min	 		= SCTP_RTO_MIN;
1307	/* RTO.Max                 -  60 seconds */
1308	net->sctp.rto_max 			= SCTP_RTO_MAX;
1309	/* RTO.Alpha                - 1/8 */
1310	net->sctp.rto_alpha			= SCTP_RTO_ALPHA;
1311	/* RTO.Beta                 - 1/4 */
1312	net->sctp.rto_beta			= SCTP_RTO_BETA;
1313
1314	/* Valid.Cookie.Life        - 60  seconds */
1315	net->sctp.valid_cookie_life		= SCTP_DEFAULT_COOKIE_LIFE;
1316
1317	/* Whether Cookie Preservative is enabled(1) or not(0) */
1318	net->sctp.cookie_preserve_enable 	= 1;
1319
1320	/* Default sctp sockets to use md5 as their hmac alg */
1321#if defined (CONFIG_SCTP_DEFAULT_COOKIE_HMAC_MD5)
1322	net->sctp.sctp_hmac_alg			= "md5";
1323#elif defined (CONFIG_SCTP_DEFAULT_COOKIE_HMAC_SHA1)
1324	net->sctp.sctp_hmac_alg			= "sha1";
1325#else
1326	net->sctp.sctp_hmac_alg			= NULL;
1327#endif
1328
1329	/* Max.Burst		    - 4 */
1330	net->sctp.max_burst			= SCTP_DEFAULT_MAX_BURST;
1331
1332	/* Disable of Primary Path Switchover by default */
1333	net->sctp.ps_retrans = SCTP_PS_RETRANS_MAX;
1334
1335	/* Enable pf state by default */
1336	net->sctp.pf_enable = 1;
1337
1338	/* Ignore pf exposure feature by default */
1339	net->sctp.pf_expose = SCTP_PF_EXPOSE_UNSET;
1340
1341	/* Association.Max.Retrans  - 10 attempts
1342	 * Path.Max.Retrans         - 5  attempts (per destination address)
1343	 * Max.Init.Retransmits     - 8  attempts
1344	 */
1345	net->sctp.max_retrans_association	= 10;
1346	net->sctp.max_retrans_path		= 5;
1347	net->sctp.max_retrans_init		= 8;
1348
1349	/* Sendbuffer growth	    - do per-socket accounting */
1350	net->sctp.sndbuf_policy			= 0;
1351
1352	/* Rcvbuffer growth	    - do per-socket accounting */
1353	net->sctp.rcvbuf_policy			= 0;
1354
1355	/* HB.interval              - 30 seconds */
1356	net->sctp.hb_interval			= SCTP_DEFAULT_TIMEOUT_HEARTBEAT;
1357
1358	/* delayed SACK timeout */
1359	net->sctp.sack_timeout			= SCTP_DEFAULT_TIMEOUT_SACK;
1360
1361	/* Disable ADDIP by default. */
1362	net->sctp.addip_enable = 0;
1363	net->sctp.addip_noauth = 0;
1364	net->sctp.default_auto_asconf = 0;
1365
1366	/* Enable PR-SCTP by default. */
1367	net->sctp.prsctp_enable = 1;
1368
1369	/* Disable RECONF by default. */
1370	net->sctp.reconf_enable = 0;
1371
1372	/* Disable AUTH by default. */
1373	net->sctp.auth_enable = 0;
1374
1375	/* Enable ECN by default. */
1376	net->sctp.ecn_enable = 1;
1377
1378	/* Set UDP tunneling listening port to 0 by default */
1379	net->sctp.udp_port = 0;
1380
1381	/* Set remote encap port to 0 by default */
1382	net->sctp.encap_port = 0;
1383
1384	/* Set SCOPE policy to enabled */
1385	net->sctp.scope_policy = SCTP_SCOPE_POLICY_ENABLE;
1386
1387	/* Set the default rwnd update threshold */
1388	net->sctp.rwnd_upd_shift = SCTP_DEFAULT_RWND_SHIFT;
1389
1390	/* Initialize maximum autoclose timeout. */
1391	net->sctp.max_autoclose		= INT_MAX / HZ;
1392
1393#ifdef CONFIG_NET_L3_MASTER_DEV
1394	net->sctp.l3mdev_accept = 1;
1395#endif
1396
1397	status = sctp_sysctl_net_register(net);
1398	if (status)
1399		goto err_sysctl_register;
1400
1401	/* Allocate and initialise sctp mibs.  */
1402	status = init_sctp_mibs(net);
1403	if (status)
1404		goto err_init_mibs;
1405
1406#ifdef CONFIG_PROC_FS
1407	/* Initialize proc fs directory.  */
1408	status = sctp_proc_init(net);
1409	if (status)
1410		goto err_init_proc;
1411#endif
1412
1413	sctp_dbg_objcnt_init(net);
1414
1415	/* Initialize the local address list. */
1416	INIT_LIST_HEAD(&net->sctp.local_addr_list);
1417	spin_lock_init(&net->sctp.local_addr_lock);
1418	sctp_get_local_addr_list(net);
1419
1420	/* Initialize the address event list */
1421	INIT_LIST_HEAD(&net->sctp.addr_waitq);
1422	INIT_LIST_HEAD(&net->sctp.auto_asconf_splist);
1423	spin_lock_init(&net->sctp.addr_wq_lock);
1424	net->sctp.addr_wq_timer.expires = 0;
1425	timer_setup(&net->sctp.addr_wq_timer, sctp_addr_wq_timeout_handler, 0);
1426
1427	return 0;
1428
1429#ifdef CONFIG_PROC_FS
1430err_init_proc:
1431	cleanup_sctp_mibs(net);
1432#endif
1433err_init_mibs:
1434	sctp_sysctl_net_unregister(net);
1435err_sysctl_register:
1436	return status;
1437}
1438
1439static void __net_exit sctp_defaults_exit(struct net *net)
1440{
1441	/* Free the local address list */
1442	sctp_free_addr_wq(net);
1443	sctp_free_local_addr_list(net);
1444
1445#ifdef CONFIG_PROC_FS
1446	remove_proc_subtree("sctp", net->proc_net);
1447	net->sctp.proc_net_sctp = NULL;
1448#endif
1449	cleanup_sctp_mibs(net);
1450	sctp_sysctl_net_unregister(net);
1451}
1452
1453static struct pernet_operations sctp_defaults_ops = {
1454	.init = sctp_defaults_init,
1455	.exit = sctp_defaults_exit,
1456};
1457
1458static int __net_init sctp_ctrlsock_init(struct net *net)
1459{
1460	int status;
1461
1462	/* Initialize the control inode/socket for handling OOTB packets.  */
1463	status = sctp_ctl_sock_init(net);
1464	if (status)
1465		pr_err("Failed to initialize the SCTP control sock\n");
1466
1467	return status;
1468}
1469
1470static void __net_exit sctp_ctrlsock_exit(struct net *net)
1471{
1472	/* Free the control endpoint.  */
1473	inet_ctl_sock_destroy(net->sctp.ctl_sock);
1474}
1475
1476static struct pernet_operations sctp_ctrlsock_ops = {
1477	.init = sctp_ctrlsock_init,
1478	.exit = sctp_ctrlsock_exit,
1479};
1480
1481/* Initialize the universe into something sensible.  */
1482static __init int sctp_init(void)
1483{
1484	unsigned long nr_pages = totalram_pages();
1485	unsigned long limit;
1486	unsigned long goal;
1487	int max_entry_order;
1488	int num_entries;
1489	int max_share;
1490	int status;
1491	int order;
1492	int i;
1493
1494	sock_skb_cb_check_size(sizeof(struct sctp_ulpevent));
1495
1496	/* Allocate bind_bucket and chunk caches. */
1497	status = -ENOBUFS;
1498	sctp_bucket_cachep = KMEM_CACHE(sctp_bind_bucket, SLAB_HWCACHE_ALIGN);
1499	if (!sctp_bucket_cachep)
1500		goto out;
1501
1502	sctp_chunk_cachep = KMEM_CACHE(sctp_chunk, SLAB_HWCACHE_ALIGN);
1503	if (!sctp_chunk_cachep)
1504		goto err_chunk_cachep;
1505
1506	status = percpu_counter_init(&sctp_sockets_allocated, 0, GFP_KERNEL);
1507	if (status)
1508		goto err_percpu_counter_init;
1509
1510	/* Implementation specific variables. */
1511
1512	/* Initialize default stream count setup information. */
1513	sctp_max_instreams    		= SCTP_DEFAULT_INSTREAMS;
1514	sctp_max_outstreams   		= SCTP_DEFAULT_OUTSTREAMS;
1515
1516	/* Initialize handle used for association ids. */
1517	idr_init(&sctp_assocs_id);
1518
1519	limit = nr_free_buffer_pages() / 8;
1520	limit = max(limit, 128UL);
1521	sysctl_sctp_mem[0] = limit / 4 * 3;
1522	sysctl_sctp_mem[1] = limit;
1523	sysctl_sctp_mem[2] = sysctl_sctp_mem[0] * 2;
1524
1525	/* Set per-socket limits to no more than 1/128 the pressure threshold*/
1526	limit = (sysctl_sctp_mem[1]) << (PAGE_SHIFT - 7);
1527	max_share = min(4UL*1024*1024, limit);
1528
1529	sysctl_sctp_rmem[0] = PAGE_SIZE; /* give each asoc 1 page min */
1530	sysctl_sctp_rmem[1] = 1500 * SKB_TRUESIZE(1);
1531	sysctl_sctp_rmem[2] = max(sysctl_sctp_rmem[1], max_share);
1532
1533	sysctl_sctp_wmem[0] = PAGE_SIZE;
1534	sysctl_sctp_wmem[1] = 16*1024;
1535	sysctl_sctp_wmem[2] = max(64*1024, max_share);
1536
1537	/* Size and allocate the association hash table.
1538	 * The methodology is similar to that of the tcp hash tables.
1539	 * Though not identical.  Start by getting a goal size
1540	 */
1541	if (nr_pages >= (128 * 1024))
1542		goal = nr_pages >> (22 - PAGE_SHIFT);
1543	else
1544		goal = nr_pages >> (24 - PAGE_SHIFT);
1545
1546	/* Then compute the page order for said goal */
1547	order = get_order(goal);
1548
1549	/* Now compute the required page order for the maximum sized table we
1550	 * want to create
1551	 */
1552	max_entry_order = get_order(MAX_SCTP_PORT_HASH_ENTRIES *
1553				    sizeof(struct sctp_bind_hashbucket));
1554
1555	/* Limit the page order by that maximum hash table size */
1556	order = min(order, max_entry_order);
1557
1558	/* Allocate and initialize the endpoint hash table.  */
1559	sctp_ep_hashsize = 64;
1560	sctp_ep_hashtable =
1561		kmalloc_array(64, sizeof(struct sctp_hashbucket), GFP_KERNEL);
1562	if (!sctp_ep_hashtable) {
1563		pr_err("Failed endpoint_hash alloc\n");
1564		status = -ENOMEM;
1565		goto err_ehash_alloc;
1566	}
1567	for (i = 0; i < sctp_ep_hashsize; i++) {
1568		rwlock_init(&sctp_ep_hashtable[i].lock);
1569		INIT_HLIST_HEAD(&sctp_ep_hashtable[i].chain);
1570	}
1571
1572	/* Allocate and initialize the SCTP port hash table.
1573	 * Note that order is initalized to start at the max sized
1574	 * table we want to support.  If we can't get that many pages
1575	 * reduce the order and try again
1576	 */
1577	do {
1578		sctp_port_hashtable = (struct sctp_bind_hashbucket *)
1579			__get_free_pages(GFP_KERNEL | __GFP_NOWARN, order);
1580	} while (!sctp_port_hashtable && --order > 0);
1581
1582	if (!sctp_port_hashtable) {
1583		pr_err("Failed bind hash alloc\n");
1584		status = -ENOMEM;
1585		goto err_bhash_alloc;
1586	}
1587
1588	/* Now compute the number of entries that will fit in the
1589	 * port hash space we allocated
1590	 */
1591	num_entries = (1UL << order) * PAGE_SIZE /
1592		      sizeof(struct sctp_bind_hashbucket);
1593
1594	/* And finish by rounding it down to the nearest power of two.
1595	 * This wastes some memory of course, but it's needed because
1596	 * the hash function operates based on the assumption that
1597	 * the number of entries is a power of two.
1598	 */
1599	sctp_port_hashsize = rounddown_pow_of_two(num_entries);
1600
1601	for (i = 0; i < sctp_port_hashsize; i++) {
1602		spin_lock_init(&sctp_port_hashtable[i].lock);
1603		INIT_HLIST_HEAD(&sctp_port_hashtable[i].chain);
1604	}
1605
1606	status = sctp_transport_hashtable_init();
1607	if (status)
1608		goto err_thash_alloc;
1609
1610	pr_info("Hash tables configured (bind %d/%d)\n", sctp_port_hashsize,
1611		num_entries);
1612
1613	sctp_sysctl_register();
1614
1615	INIT_LIST_HEAD(&sctp_address_families);
1616	sctp_v4_pf_init();
1617	sctp_v6_pf_init();
1618	sctp_sched_ops_init();
1619
1620	status = register_pernet_subsys(&sctp_defaults_ops);
1621	if (status)
1622		goto err_register_defaults;
1623
1624	status = sctp_v4_protosw_init();
1625	if (status)
1626		goto err_protosw_init;
1627
1628	status = sctp_v6_protosw_init();
1629	if (status)
1630		goto err_v6_protosw_init;
1631
1632	status = register_pernet_subsys(&sctp_ctrlsock_ops);
1633	if (status)
1634		goto err_register_ctrlsock;
1635
1636	status = sctp_v4_add_protocol();
1637	if (status)
1638		goto err_add_protocol;
1639
1640	/* Register SCTP with inet6 layer.  */
1641	status = sctp_v6_add_protocol();
1642	if (status)
1643		goto err_v6_add_protocol;
1644
1645	if (sctp_offload_init() < 0)
1646		pr_crit("%s: Cannot add SCTP protocol offload\n", __func__);
1647
1648out:
1649	return status;
1650err_v6_add_protocol:
1651	sctp_v4_del_protocol();
1652err_add_protocol:
1653	unregister_pernet_subsys(&sctp_ctrlsock_ops);
1654err_register_ctrlsock:
1655	sctp_v6_protosw_exit();
1656err_v6_protosw_init:
1657	sctp_v4_protosw_exit();
1658err_protosw_init:
1659	unregister_pernet_subsys(&sctp_defaults_ops);
1660err_register_defaults:
1661	sctp_v4_pf_exit();
1662	sctp_v6_pf_exit();
1663	sctp_sysctl_unregister();
1664	free_pages((unsigned long)sctp_port_hashtable,
1665		   get_order(sctp_port_hashsize *
1666			     sizeof(struct sctp_bind_hashbucket)));
1667err_bhash_alloc:
1668	sctp_transport_hashtable_destroy();
1669err_thash_alloc:
1670	kfree(sctp_ep_hashtable);
1671err_ehash_alloc:
1672	percpu_counter_destroy(&sctp_sockets_allocated);
1673err_percpu_counter_init:
1674	kmem_cache_destroy(sctp_chunk_cachep);
1675err_chunk_cachep:
1676	kmem_cache_destroy(sctp_bucket_cachep);
1677	goto out;
1678}
1679
1680/* Exit handler for the SCTP protocol.  */
1681static __exit void sctp_exit(void)
1682{
1683	/* BUG.  This should probably do something useful like clean
1684	 * up all the remaining associations and all that memory.
1685	 */
1686
1687	/* Unregister with inet6/inet layers. */
1688	sctp_v6_del_protocol();
1689	sctp_v4_del_protocol();
1690
1691	unregister_pernet_subsys(&sctp_ctrlsock_ops);
1692
1693	/* Free protosw registrations */
1694	sctp_v6_protosw_exit();
1695	sctp_v4_protosw_exit();
1696
1697	unregister_pernet_subsys(&sctp_defaults_ops);
1698
1699	/* Unregister with socket layer. */
1700	sctp_v6_pf_exit();
1701	sctp_v4_pf_exit();
1702
1703	sctp_sysctl_unregister();
1704
1705	free_pages((unsigned long)sctp_port_hashtable,
1706		   get_order(sctp_port_hashsize *
1707			     sizeof(struct sctp_bind_hashbucket)));
1708	kfree(sctp_ep_hashtable);
1709	sctp_transport_hashtable_destroy();
1710
1711	percpu_counter_destroy(&sctp_sockets_allocated);
1712
1713	rcu_barrier(); /* Wait for completion of call_rcu()'s */
1714
1715	kmem_cache_destroy(sctp_chunk_cachep);
1716	kmem_cache_destroy(sctp_bucket_cachep);
1717}
1718
1719module_init(sctp_init);
1720module_exit(sctp_exit);
1721
1722/*
1723 * __stringify doesn't likes enums, so use IPPROTO_SCTP value (132) directly.
1724 */
1725MODULE_ALIAS("net-pf-" __stringify(PF_INET) "-proto-132");
1726MODULE_ALIAS("net-pf-" __stringify(PF_INET6) "-proto-132");
1727MODULE_AUTHOR("Linux Kernel SCTP developers <linux-sctp@vger.kernel.org>");
1728MODULE_DESCRIPTION("Support for the SCTP protocol (RFC2960)");
1729module_param_named(no_checksums, sctp_checksum_disable, bool, 0644);
1730MODULE_PARM_DESC(no_checksums, "Disable checksums computing and verification");
1731MODULE_LICENSE("GPL");
1732