net/sctp/protocol.c

   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 <[email protected]>
  17  *
  18  * Written or modified by:
  19  *    La Monte H.P. Yarroll <[email protected]>
  20  *    Karl Knutson <[email protected]>
  21  *    Jon Grimm <[email protected]>
  22  *    Sridhar Samudrala <[email protected]>
  23  *    Daisy Chang <[email protected]>
  24  *    Ardelle Fan <[email protected]>
  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. */
  51 struct sctp_globals sctp_globals __read_mostly;
  52
  53 struct idr sctp_assocs_id;
  54 DEFINE_SPINLOCK(sctp_assocs_id_lock);
  55
  56 static struct sctp_pf *sctp_pf_inet6_specific;
  57 static struct sctp_pf *sctp_pf_inet_specific;
  58 static struct sctp_af *sctp_af_v4_specific;
  59 static struct sctp_af *sctp_af_v6_specific;
  60
  61 struct kmem_cache *sctp_chunk_cachep __read_mostly;
  62 struct kmem_cache *sctp_bucket_cachep __read_mostly;
  63
  64 long sysctl_sctp_mem[3];
  65 int sysctl_sctp_rmem[3];
  66 int sysctl_sctp_wmem[3];
  67
  68 /* Private helper to extract ipv4 address and stash them in
  69  * the protocol structure.
  70  */
  71 static 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  */
 102 static 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.  */
 119 static 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'.  */
 132 int 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 */
 176 static 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 */
 199 static 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.  */
 215 static 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. */
 235 static 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. */
 244 static 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. */
 250 static 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. */
 256 static 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  */
 274 static 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. */
 287 static 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. */
 297 static 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. */
 311 static 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? */
 320 static 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  */
 332 static 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?   */
 352 static 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            !sp->inet.freebind &&
 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  */
 390 static 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  */
 417 static 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 = 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_CONN_FLAGS_TOS(asoc->base.sk, tos);
 439                 fl4->flowi4_oif = asoc->base.sk->sk_bound_dev_if;
 440                 fl4->fl4_sport = htons(asoc->base.bind_addr.port);
 441         }
 442         if (saddr) {
 443                 fl4->saddr = saddr->v4.sin_addr.s_addr;
 444                 if (!fl4->fl4_sport)
 445                         fl4->fl4_sport = saddr->v4.sin_port;
 446         }
 447
 448         pr_debug("%s: dst:%pI4, src:%pI4 - ", __func__, &fl4->daddr,
 449                  &fl4->saddr);
 450
 451         rt = ip_route_output_key(sock_net(sk), fl4);
 452         if (!IS_ERR(rt)) {
 453                 dst = &rt->dst;
 454                 t->dst = dst;
 455                 memcpy(fl, &_fl, sizeof(_fl));
 456         }
 457
 458         /* If there is no association or if a source address is passed, no
 459          * more validation is required.
 460          */
 461         if (!asoc || saddr)
 462                 goto out;
 463
 464         bp = &asoc->base.bind_addr;
 465
 466         if (dst) {
 467                 /* Walk through the bind address list and look for a bind
 468                  * address that matches the source address of the returned dst.
 469                  */
 470                 sctp_v4_dst_saddr(&dst_saddr, fl4, htons(bp->port));
 471                 rcu_read_lock();
 472                 list_for_each_entry_rcu(laddr, &bp->address_list, list) {
 473                         if (!laddr->valid || (laddr->state == SCTP_ADDR_DEL) ||
 474                             (laddr->state != SCTP_ADDR_SRC &&
 475                             !asoc->src_out_of_asoc_ok))
 476                                 continue;
 477                         if (sctp_v4_cmp_addr(&dst_saddr, &laddr->a))
 478                                 goto out_unlock;
 479                 }
 480                 rcu_read_unlock();
 481
 482                 /* None of the bound addresses match the source address of the
 483                  * dst. So release it.
 484                  */
 485                 dst_release(dst);
 486                 dst = NULL;
 487         }
 488
 489         /* Walk through the bind address list and try to get a dst that
 490          * matches a bind address as the source address.
 491          */
 492         rcu_read_lock();
 493         list_for_each_entry_rcu(laddr, &bp->address_list, list) {
 494                 struct net_device *odev;
 495
 496                 if (!laddr->valid)
 497                         continue;
 498                 if (laddr->state != SCTP_ADDR_SRC ||
 499                     AF_INET != laddr->a.sa.sa_family)
 500                         continue;
 501
 502                 fl4->fl4_sport = laddr->a.v4.sin_port;
 503                 flowi4_update_output(fl4,
 504                                      asoc->base.sk->sk_bound_dev_if,
 505                                      RT_CONN_FLAGS_TOS(asoc->base.sk, tos),
 506                                      daddr->v4.sin_addr.s_addr,
 507                                      laddr->a.v4.sin_addr.s_addr);
 508
 509                 rt = ip_route_output_key(sock_net(sk), fl4);
 510                 if (IS_ERR(rt))
 511                         continue;
 512
 513                 /* Ensure the src address belongs to the output
 514                  * interface.
 515                  */
 516                 odev = __ip_dev_find(sock_net(sk), laddr->a.v4.sin_addr.s_addr,
 517                                      false);
 518                 if (!odev || odev->ifindex != fl4->flowi4_oif) {
 519                         if (!dst) {
 520                                 dst = &rt->dst;
 521                                 t->dst = dst;
 522                                 memcpy(fl, &_fl, sizeof(_fl));
 523                         } else {
 524                                 dst_release(&rt->dst);
 525                         }
 526                         continue;
 527                 }
 528
 529                 dst_release(dst);
 530                 dst = &rt->dst;
 531                 t->dst = dst;
 532                 memcpy(fl, &_fl, sizeof(_fl));
 533                 break;
 534         }
 535
 536 out_unlock:
 537         rcu_read_unlock();
 538 out:
 539         if (dst) {
 540                 pr_debug("rt_dst:%pI4, rt_src:%pI4\n",
 541                          &fl->u.ip4.daddr, &fl->u.ip4.saddr);
 542         } else {
 543                 t->dst = NULL;
 544                 pr_debug("no route\n");
 545         }
 546 }
 547
 548 /* For v4, the source address is cached in the route entry(dst). So no need
 549  * to cache it separately and hence this is an empty routine.
 550  */
 551 static void sctp_v4_get_saddr(struct sctp_sock *sk,
 552                               struct sctp_transport *t,
 553                               struct flowi *fl)
 554 {
 555         union sctp_addr *saddr = &t->saddr;
 556         struct rtable *rt = (struct rtable *)t->dst;
 557
 558         if (rt) {
 559                 saddr->v4.sin_family = AF_INET;
 560                 saddr->v4.sin_addr.s_addr = fl->u.ip4.saddr;
 561         }
 562 }
 563
 564 /* What interface did this skb arrive on? */
 565 static int sctp_v4_skb_iif(const struct sk_buff *skb)
 566 {
 567         return inet_iif(skb);
 568 }
 569
 570 static int sctp_v4_skb_sdif(const struct sk_buff *skb)
 571 {
 572         return inet_sdif(skb);
 573 }
 574
 575 /* Was this packet marked by Explicit Congestion Notification? */
 576 static int sctp_v4_is_ce(const struct sk_buff *skb)
 577 {
 578         return INET_ECN_is_ce(ip_hdr(skb)->tos);
 579 }
 580
 581 /* Create and initialize a new sk for the socket returned by accept(). */
 582 static struct sock *sctp_v4_create_accept_sk(struct sock *sk,
 583                                              struct sctp_association *asoc,
 584                                              bool kern)
 585 {
 586         struct sock *newsk = sk_alloc(sock_net(sk), PF_INET, GFP_KERNEL,
 587                         sk->sk_prot, kern);
 588         struct inet_sock *newinet;
 589
 590         if (!newsk)
 591                 goto out;
 592
 593         sock_init_data(NULL, newsk);
 594
 595         sctp_copy_sock(newsk, sk, asoc);
 596         sock_reset_flag(newsk, SOCK_ZAPPED);
 597
 598         sctp_v4_copy_ip_options(sk, newsk);
 599
 600         newinet = inet_sk(newsk);
 601
 602         newinet->inet_daddr = asoc->peer.primary_addr.v4.sin_addr.s_addr;
 603
 604         if (newsk->sk_prot->init(newsk)) {
 605                 sk_common_release(newsk);
 606                 newsk = NULL;
 607         }
 608
 609 out:
 610         return newsk;
 611 }
 612
 613 static int sctp_v4_addr_to_user(struct sctp_sock *sp, union sctp_addr *addr)
 614 {
 615         /* No address mapping for V4 sockets */
 616         memset(addr->v4.sin_zero, 0, sizeof(addr->v4.sin_zero));
 617         return sizeof(struct sockaddr_in);
 618 }
 619
 620 /* Dump the v4 addr to the seq file. */
 621 static void sctp_v4_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
 622 {
 623         seq_printf(seq, "%pI4 ", &addr->v4.sin_addr);
 624 }
 625
 626 static void sctp_v4_ecn_capable(struct sock *sk)
 627 {
 628         INET_ECN_xmit(sk);
 629 }
 630
 631 static void sctp_addr_wq_timeout_handler(struct timer_list *t)
 632 {
 633         struct net *net = from_timer(net, t, sctp.addr_wq_timer);
 634         struct sctp_sockaddr_entry *addrw, *temp;
 635         struct sctp_sock *sp;
 636
 637         spin_lock_bh(&net->sctp.addr_wq_lock);
 638
 639         list_for_each_entry_safe(addrw, temp, &net->sctp.addr_waitq, list) {
 640                 pr_debug("%s: the first ent in wq:%p is addr:%pISc for cmd:%d at "
 641                          "entry:%p\n", __func__, &net->sctp.addr_waitq, &addrw->a.sa,
 642                          addrw->state, addrw);
 643
 644 #if IS_ENABLED(CONFIG_IPV6)
 645                 /* Now we send an ASCONF for each association */
 646                 /* Note. we currently don't handle link local IPv6 addressees */
 647                 if (addrw->a.sa.sa_family == AF_INET6) {
 648                         struct in6_addr *in6;
 649
 650                         if (ipv6_addr_type(&addrw->a.v6.sin6_addr) &
 651                             IPV6_ADDR_LINKLOCAL)
 652                                 goto free_next;
 653
 654                         in6 = (struct in6_addr *)&addrw->a.v6.sin6_addr;
 655                         if (ipv6_chk_addr(net, in6, NULL, 0) == 0 &&
 656                             addrw->state == SCTP_ADDR_NEW) {
 657                                 unsigned long timeo_val;
 658
 659                                 pr_debug("%s: this is on DAD, trying %d sec "
 660                                          "later\n", __func__,
 661                                          SCTP_ADDRESS_TICK_DELAY);
 662
 663                                 timeo_val = jiffies;
 664                                 timeo_val += msecs_to_jiffies(SCTP_ADDRESS_TICK_DELAY);
 665                                 mod_timer(&net->sctp.addr_wq_timer, timeo_val);
 666                                 break;
 667                         }
 668                 }
 669 #endif
 670                 list_for_each_entry(sp, &net->sctp.auto_asconf_splist, auto_asconf_list) {
 671                         struct sock *sk;
 672
 673                         sk = sctp_opt2sk(sp);
 674                         /* ignore bound-specific endpoints */
 675                         if (!sctp_is_ep_boundall(sk))
 676                                 continue;
 677                         bh_lock_sock(sk);
 678                         if (sctp_asconf_mgmt(sp, addrw) < 0)
 679                                 pr_debug("%s: sctp_asconf_mgmt failed\n", __func__);
 680                         bh_unlock_sock(sk);
 681                 }
 682 #if IS_ENABLED(CONFIG_IPV6)
 683 free_next:
 684 #endif
 685                 list_del(&addrw->list);
 686                 kfree(addrw);
 687         }
 688         spin_unlock_bh(&net->sctp.addr_wq_lock);
 689 }
 690
 691 static void sctp_free_addr_wq(struct net *net)
 692 {
 693         struct sctp_sockaddr_entry *addrw;
 694         struct sctp_sockaddr_entry *temp;
 695
 696         spin_lock_bh(&net->sctp.addr_wq_lock);
 697         del_timer(&net->sctp.addr_wq_timer);
 698         list_for_each_entry_safe(addrw, temp, &net->sctp.addr_waitq, list) {
 699                 list_del(&addrw->list);
 700                 kfree(addrw);
 701         }
 702         spin_unlock_bh(&net->sctp.addr_wq_lock);
 703 }
 704
 705 /* lookup the entry for the same address in the addr_waitq
 706  * sctp_addr_wq MUST be locked
 707  */
 708 static struct sctp_sockaddr_entry *sctp_addr_wq_lookup(struct net *net,
 709                                         struct sctp_sockaddr_entry *addr)
 710 {
 711         struct sctp_sockaddr_entry *addrw;
 712
 713         list_for_each_entry(addrw, &net->sctp.addr_waitq, list) {
 714                 if (addrw->a.sa.sa_family != addr->a.sa.sa_family)
 715                         continue;
 716                 if (addrw->a.sa.sa_family == AF_INET) {
 717                         if (addrw->a.v4.sin_addr.s_addr ==
 718                             addr->a.v4.sin_addr.s_addr)
 719                                 return addrw;
 720                 } else if (addrw->a.sa.sa_family == AF_INET6) {
 721                         if (ipv6_addr_equal(&addrw->a.v6.sin6_addr,
 722                             &addr->a.v6.sin6_addr))
 723                                 return addrw;
 724                 }
 725         }
 726         return NULL;
 727 }
 728
 729 void sctp_addr_wq_mgmt(struct net *net, struct sctp_sockaddr_entry *addr, int cmd)
 730 {
 731         struct sctp_sockaddr_entry *addrw;
 732         unsigned long timeo_val;
 733
 734         /* first, we check if an opposite message already exist in the queue.
 735          * If we found such message, it is removed.
 736          * This operation is a bit stupid, but the DHCP client attaches the
 737          * new address after a couple of addition and deletion of that address
 738          */
 739
 740         spin_lock_bh(&net->sctp.addr_wq_lock);
 741         /* Offsets existing events in addr_wq */
 742         addrw = sctp_addr_wq_lookup(net, addr);
 743         if (addrw) {
 744                 if (addrw->state != cmd) {
 745                         pr_debug("%s: offsets existing entry for %d, addr:%pISc "
 746                                  "in wq:%p\n", __func__, addrw->state, &addrw->a.sa,
 747                                  &net->sctp.addr_waitq);
 748
 749                         list_del(&addrw->list);
 750                         kfree(addrw);
 751                 }
 752                 spin_unlock_bh(&net->sctp.addr_wq_lock);
 753                 return;
 754         }
 755
 756         /* OK, we have to add the new address to the wait queue */
 757         addrw = kmemdup(addr, sizeof(struct sctp_sockaddr_entry), GFP_ATOMIC);
 758         if (addrw == NULL) {
 759                 spin_unlock_bh(&net->sctp.addr_wq_lock);
 760                 return;
 761         }
 762         addrw->state = cmd;
 763         list_add_tail(&addrw->list, &net->sctp.addr_waitq);
 764
 765         pr_debug("%s: add new entry for cmd:%d, addr:%pISc in wq:%p\n",
 766                  __func__, addrw->state, &addrw->a.sa, &net->sctp.addr_waitq);
 767
 768         if (!timer_pending(&net->sctp.addr_wq_timer)) {
 769                 timeo_val = jiffies;
 770                 timeo_val += msecs_to_jiffies(SCTP_ADDRESS_TICK_DELAY);
 771                 mod_timer(&net->sctp.addr_wq_timer, timeo_val);
 772         }
 773         spin_unlock_bh(&net->sctp.addr_wq_lock);
 774 }
 775
 776 /* Event handler for inet address addition/deletion events.
 777  * The sctp_local_addr_list needs to be protocted by a spin lock since
 778  * multiple notifiers (say IPv4 and IPv6) may be running at the same
 779  * time and thus corrupt the list.
 780  * The reader side is protected with RCU.
 781  */
 782 static int sctp_inetaddr_event(struct notifier_block *this, unsigned long ev,
 783                                void *ptr)
 784 {
 785         struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
 786         struct sctp_sockaddr_entry *addr = NULL;
 787         struct sctp_sockaddr_entry *temp;
 788         struct net *net = dev_net(ifa->ifa_dev->dev);
 789         int found = 0;
 790
 791         switch (ev) {
 792         case NETDEV_UP:
 793                 addr = kzalloc(sizeof(*addr), GFP_ATOMIC);
 794                 if (addr) {
 795                         addr->a.v4.sin_family = AF_INET;
 796                         addr->a.v4.sin_addr.s_addr = ifa->ifa_local;
 797                         addr->valid = 1;
 798                         spin_lock_bh(&net->sctp.local_addr_lock);
 799                         list_add_tail_rcu(&addr->list, &net->sctp.local_addr_list);
 800                         sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_NEW);
 801                         spin_unlock_bh(&net->sctp.local_addr_lock);
 802                 }
 803                 break;
 804         case NETDEV_DOWN:
 805                 spin_lock_bh(&net->sctp.local_addr_lock);
 806                 list_for_each_entry_safe(addr, temp,
 807                                         &net->sctp.local_addr_list, list) {
 808                         if (addr->a.sa.sa_family == AF_INET &&
 809                                         addr->a.v4.sin_addr.s_addr ==
 810                                         ifa->ifa_local) {
 811                                 sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_DEL);
 812                                 found = 1;
 813                                 addr->valid = 0;
 814                                 list_del_rcu(&addr->list);
 815                                 break;
 816                         }
 817                 }
 818                 spin_unlock_bh(&net->sctp.local_addr_lock);
 819                 if (found)
 820                         kfree_rcu(addr, rcu);
 821                 break;
 822         }
 823
 824         return NOTIFY_DONE;
 825 }
 826
 827 /*
 828  * Initialize the control inode/socket with a control endpoint data
 829  * structure.  This endpoint is reserved exclusively for the OOTB processing.
 830  */
 831 static int sctp_ctl_sock_init(struct net *net)
 832 {
 833         int err;
 834         sa_family_t family = PF_INET;
 835
 836         if (sctp_get_pf_specific(PF_INET6))
 837                 family = PF_INET6;
 838
 839         err = inet_ctl_sock_create(&net->sctp.ctl_sock, family,
 840                                    SOCK_SEQPACKET, IPPROTO_SCTP, net);
 841
 842         /* If IPv6 socket could not be created, try the IPv4 socket */
 843         if (err < 0 && family == PF_INET6)
 844                 err = inet_ctl_sock_create(&net->sctp.ctl_sock, AF_INET,
 845                                            SOCK_SEQPACKET, IPPROTO_SCTP,
 846                                            net);
 847
 848         if (err < 0) {
 849                 pr_err("Failed to create the SCTP control socket\n");
 850                 return err;
 851         }
 852         return 0;
 853 }
 854
 855 static int sctp_udp_rcv(struct sock *sk, struct sk_buff *skb)
 856 {
 857         SCTP_INPUT_CB(skb)->encap_port = udp_hdr(skb)->source;
 858
 859         skb_set_transport_header(skb, sizeof(struct udphdr));
 860         sctp_rcv(skb);
 861         return 0;
 862 }
 863
 864 int sctp_udp_sock_start(struct net *net)
 865 {
 866         struct udp_tunnel_sock_cfg tuncfg = {NULL};
 867         struct udp_port_cfg udp_conf = {0};
 868         struct socket *sock;
 869         int err;
 870
 871         udp_conf.family = AF_INET;
 872         udp_conf.local_ip.s_addr = htonl(INADDR_ANY);
 873         udp_conf.local_udp_port = htons(net->sctp.udp_port);
 874         err = udp_sock_create(net, &udp_conf, &sock);
 875         if (err) {
 876                 pr_err("Failed to create the SCTP UDP tunneling v4 sock\n");
 877                 return err;
 878         }
 879
 880         tuncfg.encap_type = 1;
 881         tuncfg.encap_rcv = sctp_udp_rcv;
 882         tuncfg.encap_err_lookup = sctp_udp_v4_err;
 883         setup_udp_tunnel_sock(net, sock, &tuncfg);
 884         net->sctp.udp4_sock = sock->sk;
 885
 886 #if IS_ENABLED(CONFIG_IPV6)
 887         memset(&udp_conf, 0, sizeof(udp_conf));
 888
 889         udp_conf.family = AF_INET6;
 890         udp_conf.local_ip6 = in6addr_any;
 891         udp_conf.local_udp_port = htons(net->sctp.udp_port);
 892         udp_conf.use_udp6_rx_checksums = true;
 893         udp_conf.ipv6_v6only = true;
 894         err = udp_sock_create(net, &udp_conf, &sock);
 895         if (err) {
 896                 pr_err("Failed to create the SCTP UDP tunneling v6 sock\n");
 897                 udp_tunnel_sock_release(net->sctp.udp4_sock->sk_socket);
 898                 net->sctp.udp4_sock = NULL;
 899                 return err;
 900         }
 901
 902         tuncfg.encap_type = 1;
 903         tuncfg.encap_rcv = sctp_udp_rcv;
 904         tuncfg.encap_err_lookup = sctp_udp_v6_err;
 905         setup_udp_tunnel_sock(net, sock, &tuncfg);
 906         net->sctp.udp6_sock = sock->sk;
 907 #endif
 908
 909         return 0;
 910 }
 911
 912 void sctp_udp_sock_stop(struct net *net)
 913 {
 914         if (net->sctp.udp4_sock) {
 915                 udp_tunnel_sock_release(net->sctp.udp4_sock->sk_socket);
 916                 net->sctp.udp4_sock = NULL;
 917         }
 918         if (net->sctp.udp6_sock) {
 919                 udp_tunnel_sock_release(net->sctp.udp6_sock->sk_socket);
 920                 net->sctp.udp6_sock = NULL;
 921         }
 922 }
 923
 924 /* Register address family specific functions. */
 925 int sctp_register_af(struct sctp_af *af)
 926 {
 927         switch (af->sa_family) {
 928         case AF_INET:
 929                 if (sctp_af_v4_specific)
 930                         return 0;
 931                 sctp_af_v4_specific = af;
 932                 break;
 933         case AF_INET6:
 934                 if (sctp_af_v6_specific)
 935                         return 0;
 936                 sctp_af_v6_specific = af;
 937                 break;
 938         default:
 939                 return 0;
 940         }
 941
 942         INIT_LIST_HEAD(&af->list);
 943         list_add_tail(&af->list, &sctp_address_families);
 944         return 1;
 945 }
 946
 947 /* Get the table of functions for manipulating a particular address
 948  * family.
 949  */
 950 struct sctp_af *sctp_get_af_specific(sa_family_t family)
 951 {
 952         switch (family) {
 953         case AF_INET:
 954                 return sctp_af_v4_specific;
 955         case AF_INET6:
 956                 return sctp_af_v6_specific;
 957         default:
 958                 return NULL;
 959         }
 960 }
 961
 962 /* Common code to initialize a AF_INET msg_name. */
 963 static void sctp_inet_msgname(char *msgname, int *addr_len)
 964 {
 965         struct sockaddr_in *sin;
 966
 967         sin = (struct sockaddr_in *)msgname;
 968         *addr_len = sizeof(struct sockaddr_in);
 969         sin->sin_family = AF_INET;
 970         memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
 971 }
 972
 973 /* Copy the primary address of the peer primary address as the msg_name. */
 974 static void sctp_inet_event_msgname(struct sctp_ulpevent *event, char *msgname,
 975                                     int *addr_len)
 976 {
 977         struct sockaddr_in *sin, *sinfrom;
 978
 979         if (msgname) {
 980                 struct sctp_association *asoc;
 981
 982                 asoc = event->asoc;
 983                 sctp_inet_msgname(msgname, addr_len);
 984                 sin = (struct sockaddr_in *)msgname;
 985                 sinfrom = &asoc->peer.primary_addr.v4;
 986                 sin->sin_port = htons(asoc->peer.port);
 987                 sin->sin_addr.s_addr = sinfrom->sin_addr.s_addr;
 988         }
 989 }
 990
 991 /* Initialize and copy out a msgname from an inbound skb. */
 992 static void sctp_inet_skb_msgname(struct sk_buff *skb, char *msgname, int *len)
 993 {
 994         if (msgname) {
 995                 struct sctphdr *sh = sctp_hdr(skb);
 996                 struct sockaddr_in *sin = (struct sockaddr_in *)msgname;
 997
 998                 sctp_inet_msgname(msgname, len);
 999                 sin->sin_port = sh->source;
1000                 sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
1001         }
1002 }
1003
1004 /* Do we support this AF? */
1005 static int sctp_inet_af_supported(sa_family_t family, struct sctp_sock *sp)
1006 {
1007         /* PF_INET only supports AF_INET addresses. */
1008         return AF_INET == family;
1009 }
1010
1011 /* Address matching with wildcards allowed. */
1012 static int sctp_inet_cmp_addr(const union sctp_addr *addr1,
1013                               const union sctp_addr *addr2,
1014                               struct sctp_sock *opt)
1015 {
1016         /* PF_INET only supports AF_INET addresses. */
1017         if (addr1->sa.sa_family != addr2->sa.sa_family)
1018                 return 0;
1019         if (htonl(INADDR_ANY) == addr1->v4.sin_addr.s_addr ||
1020             htonl(INADDR_ANY) == addr2->v4.sin_addr.s_addr)
1021                 return 1;
1022         if (addr1->v4.sin_addr.s_addr == addr2->v4.sin_addr.s_addr)
1023                 return 1;
1024
1025         return 0;
1026 }
1027
1028 /* Verify that provided sockaddr looks bindable.  Common verification has
1029  * already been taken care of.
1030  */
1031 static int sctp_inet_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
1032 {
1033         return sctp_v4_available(addr, opt);
1034 }
1035
1036 /* Verify that sockaddr looks sendable.  Common verification has already
1037  * been taken care of.
1038  */
1039 static int sctp_inet_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
1040 {
1041         return 1;
1042 }
1043
1044 /* Fill in Supported Address Type information for INIT and INIT-ACK
1045  * chunks.  Returns number of addresses supported.
1046  */
1047 static int sctp_inet_supported_addrs(const struct sctp_sock *opt,
1048                                      __be16 *types)
1049 {
1050         types[0] = SCTP_PARAM_IPV4_ADDRESS;
1051         return 1;
1052 }
1053
1054 /* Wrapper routine that calls the ip transmit routine. */
1055 static inline int sctp_v4_xmit(struct sk_buff *skb, struct sctp_transport *t)
1056 {
1057         struct dst_entry *dst = dst_clone(t->dst);
1058         struct flowi4 *fl4 = &t->fl.u.ip4;
1059         struct sock *sk = skb->sk;
1060         struct inet_sock *inet = inet_sk(sk);
1061         __u8 dscp = inet->tos;
1062         __be16 df = 0;
1063
1064         pr_debug("%s: skb:%p, len:%d, src:%pI4, dst:%pI4\n", __func__, skb,
1065                  skb->len, &fl4->saddr, &fl4->daddr);
1066
1067         if (t->dscp & SCTP_DSCP_SET_MASK)
1068                 dscp = t->dscp & SCTP_DSCP_VAL_MASK;
1069
1070         inet->pmtudisc = t->param_flags & SPP_PMTUD_ENABLE ? IP_PMTUDISC_DO
1071                                                            : IP_PMTUDISC_DONT;
1072         SCTP_INC_STATS(sock_net(sk), SCTP_MIB_OUTSCTPPACKS);
1073
1074         if (!t->encap_port || !sctp_sk(sk)->udp_port) {
1075                 skb_dst_set(skb, dst);
1076                 return __ip_queue_xmit(sk, skb, &t->fl, dscp);
1077         }
1078
1079         if (skb_is_gso(skb))
1080                 skb_shinfo(skb)->gso_type |= SKB_GSO_UDP_TUNNEL_CSUM;
1081
1082         if (ip_dont_fragment(sk, dst) && !skb->ignore_df)
1083                 df = htons(IP_DF);
1084
1085         skb->encapsulation = 1;
1086         skb_reset_inner_mac_header(skb);
1087         skb_reset_inner_transport_header(skb);
1088         skb_set_inner_ipproto(skb, IPPROTO_SCTP);
1089         udp_tunnel_xmit_skb((struct rtable *)dst, sk, skb, fl4->saddr,
1090                             fl4->daddr, dscp, ip4_dst_hoplimit(dst), df,
1091                             sctp_sk(sk)->udp_port, t->encap_port, false, false);
1092         return 0;
1093 }
1094
1095 static struct sctp_af sctp_af_inet;
1096
1097 static struct sctp_pf sctp_pf_inet = {
1098         .event_msgname = sctp_inet_event_msgname,
1099         .skb_msgname   = sctp_inet_skb_msgname,
1100         .af_supported  = sctp_inet_af_supported,
1101         .cmp_addr      = sctp_inet_cmp_addr,
1102         .bind_verify   = sctp_inet_bind_verify,
1103         .send_verify   = sctp_inet_send_verify,
1104         .supported_addrs = sctp_inet_supported_addrs,
1105         .create_accept_sk = sctp_v4_create_accept_sk,
1106         .addr_to_user  = sctp_v4_addr_to_user,
1107         .to_sk_saddr   = sctp_v4_to_sk_saddr,
1108         .to_sk_daddr   = sctp_v4_to_sk_daddr,
1109         .copy_ip_options = sctp_v4_copy_ip_options,
1110         .af            = &sctp_af_inet
1111 };
1112
1113 /* Notifier for inetaddr addition/deletion events.  */
1114 static struct notifier_block sctp_inetaddr_notifier = {
1115         .notifier_call = sctp_inetaddr_event,
1116 };
1117
1118 /* Socket operations.  */
1119 static const struct proto_ops inet_seqpacket_ops = {
1120         .family            = PF_INET,
1121         .owner             = THIS_MODULE,
1122         .release           = inet_release,      /* Needs to be wrapped... */
1123         .bind              = inet_bind,
1124         .connect           = sctp_inet_connect,
1125         .socketpair        = sock_no_socketpair,
1126         .accept            = inet_accept,
1127         .getname           = inet_getname,      /* Semantics are different.  */
1128         .poll              = sctp_poll,
1129         .ioctl             = inet_ioctl,
1130         .gettstamp         = sock_gettstamp,
1131         .listen            = sctp_inet_listen,
1132         .shutdown          = inet_shutdown,     /* Looks harmless.  */
1133         .setsockopt        = sock_common_setsockopt, /* IP_SOL IP_OPTION is a problem */
1134         .getsockopt        = sock_common_getsockopt,
1135         .sendmsg           = inet_sendmsg,
1136         .recvmsg           = inet_recvmsg,
1137         .mmap              = sock_no_mmap,
1138         .sendpage          = sock_no_sendpage,
1139 };
1140
1141 /* Registration with AF_INET family.  */
1142 static struct inet_protosw sctp_seqpacket_protosw = {
1143         .type       = SOCK_SEQPACKET,
1144         .protocol   = IPPROTO_SCTP,
1145         .prot       = &sctp_prot,
1146         .ops        = &inet_seqpacket_ops,
1147         .flags      = SCTP_PROTOSW_FLAG
1148 };
1149 static struct inet_protosw sctp_stream_protosw = {
1150         .type       = SOCK_STREAM,
1151         .protocol   = IPPROTO_SCTP,
1152         .prot       = &sctp_prot,
1153         .ops        = &inet_seqpacket_ops,
1154         .flags      = SCTP_PROTOSW_FLAG
1155 };
1156
1157 static int sctp4_rcv(struct sk_buff *skb)
1158 {
1159         SCTP_INPUT_CB(skb)->encap_port = 0;
1160         return sctp_rcv(skb);
1161 }
1162
1163 /* Register with IP layer.  */
1164 static const struct net_protocol sctp_protocol = {
1165         .handler     = sctp4_rcv,
1166         .err_handler = sctp_v4_err,
1167         .no_policy   = 1,
1168         .icmp_strict_tag_validation = 1,
1169 };
1170
1171 /* IPv4 address related functions.  */
1172 static struct sctp_af sctp_af_inet = {
1173         .sa_family         = AF_INET,
1174         .sctp_xmit         = sctp_v4_xmit,
1175         .setsockopt        = ip_setsockopt,
1176         .getsockopt        = ip_getsockopt,
1177         .get_dst           = sctp_v4_get_dst,
1178         .get_saddr         = sctp_v4_get_saddr,
1179         .copy_addrlist     = sctp_v4_copy_addrlist,
1180         .from_skb          = sctp_v4_from_skb,
1181         .from_sk           = sctp_v4_from_sk,
1182         .from_addr_param   = sctp_v4_from_addr_param,
1183         .to_addr_param     = sctp_v4_to_addr_param,
1184         .cmp_addr          = sctp_v4_cmp_addr,
1185         .addr_valid        = sctp_v4_addr_valid,
1186         .inaddr_any        = sctp_v4_inaddr_any,
1187         .is_any            = sctp_v4_is_any,
1188         .available         = sctp_v4_available,
1189         .scope             = sctp_v4_scope,
1190         .skb_iif           = sctp_v4_skb_iif,
1191         .skb_sdif          = sctp_v4_skb_sdif,
1192         .is_ce             = sctp_v4_is_ce,
1193         .seq_dump_addr     = sctp_v4_seq_dump_addr,
1194         .ecn_capable       = sctp_v4_ecn_capable,
1195         .net_header_len    = sizeof(struct iphdr),
1196         .sockaddr_len      = sizeof(struct sockaddr_in),
1197         .ip_options_len    = sctp_v4_ip_options_len,
1198 };
1199
1200 struct sctp_pf *sctp_get_pf_specific(sa_family_t family)
1201 {
1202         switch (family) {
1203         case PF_INET:
1204                 return sctp_pf_inet_specific;
1205         case PF_INET6:
1206                 return sctp_pf_inet6_specific;
1207         default:
1208                 return NULL;
1209         }
1210 }
1211
1212 /* Register the PF specific function table.  */
1213 int sctp_register_pf(struct sctp_pf *pf, sa_family_t family)
1214 {
1215         switch (family) {
1216         case PF_INET:
1217                 if (sctp_pf_inet_specific)
1218                         return 0;
1219                 sctp_pf_inet_specific = pf;
1220                 break;
1221         case PF_INET6:
1222                 if (sctp_pf_inet6_specific)
1223                         return 0;
1224                 sctp_pf_inet6_specific = pf;
1225                 break;
1226         default:
1227                 return 0;
1228         }
1229         return 1;
1230 }
1231
1232 static inline int init_sctp_mibs(struct net *net)
1233 {
1234         net->sctp.sctp_statistics = alloc_percpu(struct sctp_mib);
1235         if (!net->sctp.sctp_statistics)
1236                 return -ENOMEM;
1237         return 0;
1238 }
1239
1240 static inline void cleanup_sctp_mibs(struct net *net)
1241 {
1242         free_percpu(net->sctp.sctp_statistics);
1243 }
1244
1245 static void sctp_v4_pf_init(void)
1246 {
1247         /* Initialize the SCTP specific PF functions. */
1248         sctp_register_pf(&sctp_pf_inet, PF_INET);
1249         sctp_register_af(&sctp_af_inet);
1250 }
1251
1252 static void sctp_v4_pf_exit(void)
1253 {
1254         list_del(&sctp_af_inet.list);
1255 }
1256
1257 static int sctp_v4_protosw_init(void)
1258 {
1259         int rc;
1260
1261         rc = proto_register(&sctp_prot, 1);
1262         if (rc)
1263                 return rc;
1264
1265         /* Register SCTP(UDP and TCP style) with socket layer.  */
1266         inet_register_protosw(&sctp_seqpacket_protosw);
1267         inet_register_protosw(&sctp_stream_protosw);
1268
1269         return 0;
1270 }
1271
1272 static void sctp_v4_protosw_exit(void)
1273 {
1274         inet_unregister_protosw(&sctp_stream_protosw);
1275         inet_unregister_protosw(&sctp_seqpacket_protosw);
1276         proto_unregister(&sctp_prot);
1277 }
1278
1279 static int sctp_v4_add_protocol(void)
1280 {
1281         /* Register notifier for inet address additions/deletions. */
1282         register_inetaddr_notifier(&sctp_inetaddr_notifier);
1283
1284         /* Register SCTP with inet layer.  */
1285         if (inet_add_protocol(&sctp_protocol, IPPROTO_SCTP) < 0)
1286                 return -EAGAIN;
1287
1288         return 0;
1289 }
1290
1291 static void sctp_v4_del_protocol(void)
1292 {
1293         inet_del_protocol(&sctp_protocol, IPPROTO_SCTP);
1294         unregister_inetaddr_notifier(&sctp_inetaddr_notifier);
1295 }
1296
1297 static int __net_init sctp_defaults_init(struct net *net)
1298 {
1299         int status;
1300
1301         /*
1302          * 14. Suggested SCTP Protocol Parameter Values
1303          */
1304         /* The following protocol parameters are RECOMMENDED:  */
1305         /* RTO.Initial              - 3  seconds */
1306         net->sctp.rto_initial                   = SCTP_RTO_INITIAL;
1307         /* RTO.Min                  - 1  second */
1308         net->sctp.rto_min                       = SCTP_RTO_MIN;
1309         /* RTO.Max                 -  60 seconds */
1310         net->sctp.rto_max                       = SCTP_RTO_MAX;
1311         /* RTO.Alpha                - 1/8 */
1312         net->sctp.rto_alpha                     = SCTP_RTO_ALPHA;
1313         /* RTO.Beta                 - 1/4 */
1314         net->sctp.rto_beta                      = SCTP_RTO_BETA;
1315
1316         /* Valid.Cookie.Life        - 60  seconds */
1317         net->sctp.valid_cookie_life             = SCTP_DEFAULT_COOKIE_LIFE;
1318
1319         /* Whether Cookie Preservative is enabled(1) or not(0) */
1320         net->sctp.cookie_preserve_enable        = 1;
1321
1322         /* Default sctp sockets to use md5 as their hmac alg */
1323 #if defined (CONFIG_SCTP_DEFAULT_COOKIE_HMAC_MD5)
1324         net->sctp.sctp_hmac_alg                 = "md5";
1325 #elif defined (CONFIG_SCTP_DEFAULT_COOKIE_HMAC_SHA1)
1326         net->sctp.sctp_hmac_alg                 = "sha1";
1327 #else
1328         net->sctp.sctp_hmac_alg                 = NULL;
1329 #endif
1330
1331         /* Max.Burst                - 4 */
1332         net->sctp.max_burst                     = SCTP_DEFAULT_MAX_BURST;
1333
1334         /* Disable of Primary Path Switchover by default */
1335         net->sctp.ps_retrans = SCTP_PS_RETRANS_MAX;
1336
1337         /* Enable pf state by default */
1338         net->sctp.pf_enable = 1;
1339
1340         /* Ignore pf exposure feature by default */
1341         net->sctp.pf_expose = SCTP_PF_EXPOSE_UNSET;
1342
1343         /* Association.Max.Retrans  - 10 attempts
1344          * Path.Max.Retrans         - 5  attempts (per destination address)
1345          * Max.Init.Retransmits     - 8  attempts
1346          */
1347         net->sctp.max_retrans_association       = 10;
1348         net->sctp.max_retrans_path              = 5;
1349         net->sctp.max_retrans_init              = 8;
1350
1351         /* Sendbuffer growth        - do per-socket accounting */
1352         net->sctp.sndbuf_policy                 = 0;
1353
1354         /* Rcvbuffer growth         - do per-socket accounting */
1355         net->sctp.rcvbuf_policy                 = 0;
1356
1357         /* HB.interval              - 30 seconds */
1358         net->sctp.hb_interval                   = SCTP_DEFAULT_TIMEOUT_HEARTBEAT;
1359
1360         /* delayed SACK timeout */
1361         net->sctp.sack_timeout                  = SCTP_DEFAULT_TIMEOUT_SACK;
1362
1363         /* Disable ADDIP by default. */
1364         net->sctp.addip_enable = 0;
1365         net->sctp.addip_noauth = 0;
1366         net->sctp.default_auto_asconf = 0;
1367
1368         /* Enable PR-SCTP by default. */
1369         net->sctp.prsctp_enable = 1;
1370
1371         /* Disable RECONF by default. */
1372         net->sctp.reconf_enable = 0;
1373
1374         /* Disable AUTH by default. */
1375         net->sctp.auth_enable = 0;
1376
1377         /* Enable ECN by default. */
1378         net->sctp.ecn_enable = 1;
1379
1380         /* Set UDP tunneling listening port to 0 by default */
1381         net->sctp.udp_port = 0;
1382
1383         /* Set remote encap port to 0 by default */
1384         net->sctp.encap_port = 0;
1385
1386         /* Set SCOPE policy to enabled */
1387         net->sctp.scope_policy = SCTP_SCOPE_POLICY_ENABLE;
1388
1389         /* Set the default rwnd update threshold */
1390         net->sctp.rwnd_upd_shift = SCTP_DEFAULT_RWND_SHIFT;
1391
1392         /* Initialize maximum autoclose timeout. */
1393         net->sctp.max_autoclose         = INT_MAX / HZ;
1394
1395 #ifdef CONFIG_NET_L3_MASTER_DEV
1396         net->sctp.l3mdev_accept = 1;
1397 #endif
1398
1399         status = sctp_sysctl_net_register(net);
1400         if (status)
1401                 goto err_sysctl_register;
1402
1403         /* Allocate and initialise sctp mibs.  */
1404         status = init_sctp_mibs(net);
1405         if (status)
1406                 goto err_init_mibs;
1407
1408 #ifdef CONFIG_PROC_FS
1409         /* Initialize proc fs directory.  */
1410         status = sctp_proc_init(net);
1411         if (status)
1412                 goto err_init_proc;
1413 #endif
1414
1415         sctp_dbg_objcnt_init(net);
1416
1417         /* Initialize the local address list. */
1418         INIT_LIST_HEAD(&net->sctp.local_addr_list);
1419         spin_lock_init(&net->sctp.local_addr_lock);
1420         sctp_get_local_addr_list(net);
1421
1422         /* Initialize the address event list */
1423         INIT_LIST_HEAD(&net->sctp.addr_waitq);
1424         INIT_LIST_HEAD(&net->sctp.auto_asconf_splist);
1425         spin_lock_init(&net->sctp.addr_wq_lock);
1426         net->sctp.addr_wq_timer.expires = 0;
1427         timer_setup(&net->sctp.addr_wq_timer, sctp_addr_wq_timeout_handler, 0);
1428
1429         return 0;
1430
1431 #ifdef CONFIG_PROC_FS
1432 err_init_proc:
1433         cleanup_sctp_mibs(net);
1434 #endif
1435 err_init_mibs:
1436         sctp_sysctl_net_unregister(net);
1437 err_sysctl_register:
1438         return status;
1439 }
1440
1441 static void __net_exit sctp_defaults_exit(struct net *net)
1442 {
1443         /* Free the local address list */
1444         sctp_free_addr_wq(net);
1445         sctp_free_local_addr_list(net);
1446
1447 #ifdef CONFIG_PROC_FS
1448         remove_proc_subtree("sctp", net->proc_net);
1449         net->sctp.proc_net_sctp = NULL;
1450 #endif
1451         cleanup_sctp_mibs(net);
1452         sctp_sysctl_net_unregister(net);
1453 }
1454
1455 static struct pernet_operations sctp_defaults_ops = {
1456         .init = sctp_defaults_init,
1457         .exit = sctp_defaults_exit,
1458 };
1459
1460 static int __net_init sctp_ctrlsock_init(struct net *net)
1461 {
1462         int status;
1463
1464         /* Initialize the control inode/socket for handling OOTB packets.  */
1465         status = sctp_ctl_sock_init(net);
1466         if (status)
1467                 pr_err("Failed to initialize the SCTP control sock\n");
1468
1469         return status;
1470 }
1471
1472 static void __net_exit sctp_ctrlsock_exit(struct net *net)
1473 {
1474         /* Free the control endpoint.  */
1475         inet_ctl_sock_destroy(net->sctp.ctl_sock);
1476 }
1477
1478 static struct pernet_operations sctp_ctrlsock_ops = {
1479         .init = sctp_ctrlsock_init,
1480         .exit = sctp_ctrlsock_exit,
1481 };
1482
1483 /* Initialize the universe into something sensible.  */
1484 static __init int sctp_init(void)
1485 {
1486         unsigned long nr_pages = totalram_pages();
1487         unsigned long limit;
1488         unsigned long goal;
1489         int max_entry_order;
1490         int num_entries;
1491         int max_share;
1492         int status;
1493         int order;
1494         int i;
1495
1496         sock_skb_cb_check_size(sizeof(struct sctp_ulpevent));
1497
1498         /* Allocate bind_bucket and chunk caches. */
1499         status = -ENOBUFS;
1500         sctp_bucket_cachep = kmem_cache_create("sctp_bind_bucket",
1501                                                sizeof(struct sctp_bind_bucket),
1502                                                0, SLAB_HWCACHE_ALIGN,
1503                                                NULL);
1504         if (!sctp_bucket_cachep)
1505                 goto out;
1506
1507         sctp_chunk_cachep = kmem_cache_create("sctp_chunk",
1508                                                sizeof(struct sctp_chunk),
1509                                                0, SLAB_HWCACHE_ALIGN,
1510                                                NULL);
1511         if (!sctp_chunk_cachep)
1512                 goto err_chunk_cachep;
1513
1514         status = percpu_counter_init(&sctp_sockets_allocated, 0, GFP_KERNEL);
1515         if (status)
1516                 goto err_percpu_counter_init;
1517
1518         /* Implementation specific variables. */
1519
1520         /* Initialize default stream count setup information. */
1521         sctp_max_instreams              = SCTP_DEFAULT_INSTREAMS;
1522         sctp_max_outstreams             = SCTP_DEFAULT_OUTSTREAMS;
1523
1524         /* Initialize handle used for association ids. */
1525         idr_init(&sctp_assocs_id);
1526
1527         limit = nr_free_buffer_pages() / 8;
1528         limit = max(limit, 128UL);
1529         sysctl_sctp_mem[0] = limit / 4 * 3;
1530         sysctl_sctp_mem[1] = limit;
1531         sysctl_sctp_mem[2] = sysctl_sctp_mem[0] * 2;
1532
1533         /* Set per-socket limits to no more than 1/128 the pressure threshold*/
1534         limit = (sysctl_sctp_mem[1]) << (PAGE_SHIFT - 7);
1535         max_share = min(4UL*1024*1024, limit);
1536
1537         sysctl_sctp_rmem[0] = PAGE_SIZE; /* give each asoc 1 page min */
1538         sysctl_sctp_rmem[1] = 1500 * SKB_TRUESIZE(1);
1539         sysctl_sctp_rmem[2] = max(sysctl_sctp_rmem[1], max_share);
1540
1541         sysctl_sctp_wmem[0] = PAGE_SIZE;
1542         sysctl_sctp_wmem[1] = 16*1024;
1543         sysctl_sctp_wmem[2] = max(64*1024, max_share);
1544
1545         /* Size and allocate the association hash table.
1546          * The methodology is similar to that of the tcp hash tables.
1547          * Though not identical.  Start by getting a goal size
1548          */
1549         if (nr_pages >= (128 * 1024))
1550                 goal = nr_pages >> (22 - PAGE_SHIFT);
1551         else
1552                 goal = nr_pages >> (24 - PAGE_SHIFT);
1553
1554         /* Then compute the page order for said goal */
1555         order = get_order(goal);
1556
1557         /* Now compute the required page order for the maximum sized table we
1558          * want to create
1559          */
1560         max_entry_order = get_order(MAX_SCTP_PORT_HASH_ENTRIES *
1561                                     sizeof(struct sctp_bind_hashbucket));
1562
1563         /* Limit the page order by that maximum hash table size */
1564         order = min(order, max_entry_order);
1565
1566         /* Allocate and initialize the endpoint hash table.  */
1567         sctp_ep_hashsize = 64;
1568         sctp_ep_hashtable =
1569                 kmalloc_array(64, sizeof(struct sctp_hashbucket), GFP_KERNEL);
1570         if (!sctp_ep_hashtable) {
1571                 pr_err("Failed endpoint_hash alloc\n");
1572                 status = -ENOMEM;
1573                 goto err_ehash_alloc;
1574         }
1575         for (i = 0; i < sctp_ep_hashsize; i++) {
1576                 rwlock_init(&sctp_ep_hashtable[i].lock);
1577                 INIT_HLIST_HEAD(&sctp_ep_hashtable[i].chain);
1578         }
1579
1580         /* Allocate and initialize the SCTP port hash table.
1581          * Note that order is initalized to start at the max sized
1582          * table we want to support.  If we can't get that many pages
1583          * reduce the order and try again
1584          */
1585         do {
1586                 sctp_port_hashtable = (struct sctp_bind_hashbucket *)
1587                         __get_free_pages(GFP_KERNEL | __GFP_NOWARN, order);
1588         } while (!sctp_port_hashtable && --order > 0);
1589
1590         if (!sctp_port_hashtable) {
1591                 pr_err("Failed bind hash alloc\n");
1592                 status = -ENOMEM;
1593                 goto err_bhash_alloc;
1594         }
1595
1596         /* Now compute the number of entries that will fit in the
1597          * port hash space we allocated
1598          */
1599         num_entries = (1UL << order) * PAGE_SIZE /
1600                       sizeof(struct sctp_bind_hashbucket);
1601
1602         /* And finish by rounding it down to the nearest power of two.
1603          * This wastes some memory of course, but it's needed because
1604          * the hash function operates based on the assumption that
1605          * the number of entries is a power of two.
1606          */
1607         sctp_port_hashsize = rounddown_pow_of_two(num_entries);
1608
1609         for (i = 0; i < sctp_port_hashsize; i++) {
1610                 spin_lock_init(&sctp_port_hashtable[i].lock);
1611                 INIT_HLIST_HEAD(&sctp_port_hashtable[i].chain);
1612         }
1613
1614         status = sctp_transport_hashtable_init();
1615         if (status)
1616                 goto err_thash_alloc;
1617
1618         pr_info("Hash tables configured (bind %d/%d)\n", sctp_port_hashsize,
1619                 num_entries);
1620
1621         sctp_sysctl_register();
1622
1623         INIT_LIST_HEAD(&sctp_address_families);
1624         sctp_v4_pf_init();
1625         sctp_v6_pf_init();
1626         sctp_sched_ops_init();
1627
1628         status = register_pernet_subsys(&sctp_defaults_ops);
1629         if (status)
1630                 goto err_register_defaults;
1631
1632         status = sctp_v4_protosw_init();
1633         if (status)
1634                 goto err_protosw_init;
1635
1636         status = sctp_v6_protosw_init();
1637         if (status)
1638                 goto err_v6_protosw_init;
1639
1640         status = register_pernet_subsys(&sctp_ctrlsock_ops);
1641         if (status)
1642                 goto err_register_ctrlsock;
1643
1644         status = sctp_v4_add_protocol();
1645         if (status)
1646                 goto err_add_protocol;
1647
1648         /* Register SCTP with inet6 layer.  */
1649         status = sctp_v6_add_protocol();
1650         if (status)
1651                 goto err_v6_add_protocol;
1652
1653         if (sctp_offload_init() < 0)
1654                 pr_crit("%s: Cannot add SCTP protocol offload\n", __func__);
1655
1656 out:
1657         return status;
1658 err_v6_add_protocol:
1659         sctp_v4_del_protocol();
1660 err_add_protocol:
1661         unregister_pernet_subsys(&sctp_ctrlsock_ops);
1662 err_register_ctrlsock:
1663         sctp_v6_protosw_exit();
1664 err_v6_protosw_init:
1665         sctp_v4_protosw_exit();
1666 err_protosw_init:
1667         unregister_pernet_subsys(&sctp_defaults_ops);
1668 err_register_defaults:
1669         sctp_v4_pf_exit();
1670         sctp_v6_pf_exit();
1671         sctp_sysctl_unregister();
1672         free_pages((unsigned long)sctp_port_hashtable,
1673                    get_order(sctp_port_hashsize *
1674                              sizeof(struct sctp_bind_hashbucket)));
1675 err_bhash_alloc:
1676         sctp_transport_hashtable_destroy();
1677 err_thash_alloc:
1678         kfree(sctp_ep_hashtable);
1679 err_ehash_alloc:
1680         percpu_counter_destroy(&sctp_sockets_allocated);
1681 err_percpu_counter_init:
1682         kmem_cache_destroy(sctp_chunk_cachep);
1683 err_chunk_cachep:
1684         kmem_cache_destroy(sctp_bucket_cachep);
1685         goto out;
1686 }
1687
1688 /* Exit handler for the SCTP protocol.  */
1689 static __exit void sctp_exit(void)
1690 {
1691         /* BUG.  This should probably do something useful like clean
1692          * up all the remaining associations and all that memory.
1693          */
1694
1695         /* Unregister with inet6/inet layers. */
1696         sctp_v6_del_protocol();
1697         sctp_v4_del_protocol();
1698
1699         unregister_pernet_subsys(&sctp_ctrlsock_ops);
1700
1701         /* Free protosw registrations */
1702         sctp_v6_protosw_exit();
1703         sctp_v4_protosw_exit();
1704
1705         unregister_pernet_subsys(&sctp_defaults_ops);
1706
1707         /* Unregister with socket layer. */
1708         sctp_v6_pf_exit();
1709         sctp_v4_pf_exit();
1710
1711         sctp_sysctl_unregister();
1712
1713         free_pages((unsigned long)sctp_port_hashtable,
1714                    get_order(sctp_port_hashsize *
1715                              sizeof(struct sctp_bind_hashbucket)));
1716         kfree(sctp_ep_hashtable);
1717         sctp_transport_hashtable_destroy();
1718
1719         percpu_counter_destroy(&sctp_sockets_allocated);
1720
1721         rcu_barrier(); /* Wait for completion of call_rcu()'s */
1722
1723         kmem_cache_destroy(sctp_chunk_cachep);
1724         kmem_cache_destroy(sctp_bucket_cachep);
1725 }
1726
1727 module_init(sctp_init);
1728 module_exit(sctp_exit);
1729
1730 /*
1731  * __stringify doesn't likes enums, so use IPPROTO_SCTP value (132) directly.
1732  */
1733 MODULE_ALIAS("net-pf-" __stringify(PF_INET) "-proto-132");
1734 MODULE_ALIAS("net-pf-" __stringify(PF_INET6) "-proto-132");
1735 MODULE_AUTHOR("Linux Kernel SCTP developers <[email protected]>");
1736 MODULE_DESCRIPTION("Support for the SCTP protocol (RFC2960)");
1737 module_param_named(no_checksums, sctp_checksum_disable, bool, 0644);
1738 MODULE_PARM_DESC(no_checksums, "Disable checksums computing and verification");
1739 MODULE_LICENSE("GPL");