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