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