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