linux/net/ipv4/af_inet.c
<<
>>
Prefs
   1/*
   2 * INET         An implementation of the TCP/IP protocol suite for the LINUX
   3 *              operating system.  INET is implemented using the  BSD Socket
   4 *              interface as the means of communication with the user level.
   5 *
   6 *              PF_INET protocol family socket handler.
   7 *
   8 * Authors:     Ross Biro
   9 *              Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
  10 *              Florian La Roche, <flla@stud.uni-sb.de>
  11 *              Alan Cox, <A.Cox@swansea.ac.uk>
  12 *
  13 * Changes (see also sock.c)
  14 *
  15 *              piggy,
  16 *              Karl Knutson    :       Socket protocol table
  17 *              A.N.Kuznetsov   :       Socket death error in accept().
  18 *              John Richardson :       Fix non blocking error in connect()
  19 *                                      so sockets that fail to connect
  20 *                                      don't return -EINPROGRESS.
  21 *              Alan Cox        :       Asynchronous I/O support
  22 *              Alan Cox        :       Keep correct socket pointer on sock
  23 *                                      structures
  24 *                                      when accept() ed
  25 *              Alan Cox        :       Semantics of SO_LINGER aren't state
  26 *                                      moved to close when you look carefully.
  27 *                                      With this fixed and the accept bug fixed
  28 *                                      some RPC stuff seems happier.
  29 *              Niibe Yutaka    :       4.4BSD style write async I/O
  30 *              Alan Cox,
  31 *              Tony Gale       :       Fixed reuse semantics.
  32 *              Alan Cox        :       bind() shouldn't abort existing but dead
  33 *                                      sockets. Stops FTP netin:.. I hope.
  34 *              Alan Cox        :       bind() works correctly for RAW sockets.
  35 *                                      Note that FreeBSD at least was broken
  36 *                                      in this respect so be careful with
  37 *                                      compatibility tests...
  38 *              Alan Cox        :       routing cache support
  39 *              Alan Cox        :       memzero the socket structure for
  40 *                                      compactness.
  41 *              Matt Day        :       nonblock connect error handler
  42 *              Alan Cox        :       Allow large numbers of pending sockets
  43 *                                      (eg for big web sites), but only if
  44 *                                      specifically application requested.
  45 *              Alan Cox        :       New buffering throughout IP. Used
  46 *                                      dumbly.
  47 *              Alan Cox        :       New buffering now used smartly.
  48 *              Alan Cox        :       BSD rather than common sense
  49 *                                      interpretation of listen.
  50 *              Germano Caronni :       Assorted small races.
  51 *              Alan Cox        :       sendmsg/recvmsg basic support.
  52 *              Alan Cox        :       Only sendmsg/recvmsg now supported.
  53 *              Alan Cox        :       Locked down bind (see security list).
  54 *              Alan Cox        :       Loosened bind a little.
  55 *              Mike McLagan    :       ADD/DEL DLCI Ioctls
  56 *      Willy Konynenberg       :       Transparent proxying support.
  57 *              David S. Miller :       New socket lookup architecture.
  58 *                                      Some other random speedups.
  59 *              Cyrus Durgin    :       Cleaned up file for kmod hacks.
  60 *              Andi Kleen      :       Fix inet_stream_connect TCP race.
  61 *
  62 *              This program is free software; you can redistribute it and/or
  63 *              modify it under the terms of the GNU General Public License
  64 *              as published by the Free Software Foundation; either version
  65 *              2 of the License, or (at your option) any later version.
  66 */
  67
  68#define pr_fmt(fmt) "IPv4: " fmt
  69
  70#include <linux/err.h>
  71#include <linux/errno.h>
  72#include <linux/types.h>
  73#include <linux/socket.h>
  74#include <linux/in.h>
  75#include <linux/kernel.h>
  76#include <linux/module.h>
  77#include <linux/sched.h>
  78#include <linux/timer.h>
  79#include <linux/string.h>
  80#include <linux/sockios.h>
  81#include <linux/net.h>
  82#include <linux/capability.h>
  83#include <linux/fcntl.h>
  84#include <linux/mm.h>
  85#include <linux/interrupt.h>
  86#include <linux/stat.h>
  87#include <linux/init.h>
  88#include <linux/poll.h>
  89#include <linux/netfilter_ipv4.h>
  90#include <linux/random.h>
  91#include <linux/slab.h>
  92
  93#include <asm/uaccess.h>
  94
  95#include <linux/inet.h>
  96#include <linux/igmp.h>
  97#include <linux/inetdevice.h>
  98#include <linux/netdevice.h>
  99#include <net/checksum.h>
 100#include <net/ip.h>
 101#include <net/protocol.h>
 102#include <net/arp.h>
 103#include <net/route.h>
 104#include <net/ip_fib.h>
 105#include <net/inet_connection_sock.h>
 106#include <net/tcp.h>
 107#include <net/udp.h>
 108#include <net/udplite.h>
 109#include <net/ping.h>
 110#include <linux/skbuff.h>
 111#include <net/sock.h>
 112#include <net/raw.h>
 113#include <net/icmp.h>
 114#include <net/ipip.h>
 115#include <net/inet_common.h>
 116#include <net/xfrm.h>
 117#include <net/net_namespace.h>
 118#ifdef CONFIG_IP_MROUTE
 119#include <linux/mroute.h>
 120#endif
 121
 122
 123/* The inetsw table contains everything that inet_create needs to
 124 * build a new socket.
 125 */
 126static struct list_head inetsw[SOCK_MAX];
 127static DEFINE_SPINLOCK(inetsw_lock);
 128
 129struct ipv4_config ipv4_config;
 130EXPORT_SYMBOL(ipv4_config);
 131
 132/* New destruction routine */
 133
 134void inet_sock_destruct(struct sock *sk)
 135{
 136        struct inet_sock *inet = inet_sk(sk);
 137
 138        __skb_queue_purge(&sk->sk_receive_queue);
 139        __skb_queue_purge(&sk->sk_error_queue);
 140
 141        sk_mem_reclaim(sk);
 142
 143        if (sk->sk_type == SOCK_STREAM && sk->sk_state != TCP_CLOSE) {
 144                pr_err("Attempt to release TCP socket in state %d %p\n",
 145                       sk->sk_state, sk);
 146                return;
 147        }
 148        if (!sock_flag(sk, SOCK_DEAD)) {
 149                pr_err("Attempt to release alive inet socket %p\n", sk);
 150                return;
 151        }
 152
 153        WARN_ON(atomic_read(&sk->sk_rmem_alloc));
 154        WARN_ON(atomic_read(&sk->sk_wmem_alloc));
 155        WARN_ON(sk->sk_wmem_queued);
 156        WARN_ON(sk->sk_forward_alloc);
 157
 158        kfree(rcu_dereference_protected(inet->inet_opt, 1));
 159        dst_release(rcu_dereference_check(sk->sk_dst_cache, 1));
 160        dst_release(sk->sk_rx_dst);
 161        sk_refcnt_debug_dec(sk);
 162}
 163EXPORT_SYMBOL(inet_sock_destruct);
 164
 165/*
 166 *      The routines beyond this point handle the behaviour of an AF_INET
 167 *      socket object. Mostly it punts to the subprotocols of IP to do
 168 *      the work.
 169 */
 170
 171/*
 172 *      Automatically bind an unbound socket.
 173 */
 174
 175static int inet_autobind(struct sock *sk)
 176{
 177        struct inet_sock *inet;
 178        /* We may need to bind the socket. */
 179        lock_sock(sk);
 180        inet = inet_sk(sk);
 181        if (!inet->inet_num) {
 182                if (sk->sk_prot->get_port(sk, 0)) {
 183                        release_sock(sk);
 184                        return -EAGAIN;
 185                }
 186                inet->inet_sport = htons(inet->inet_num);
 187        }
 188        release_sock(sk);
 189        return 0;
 190}
 191
 192/*
 193 *      Move a socket into listening state.
 194 */
 195int inet_listen(struct socket *sock, int backlog)
 196{
 197        struct sock *sk = sock->sk;
 198        unsigned char old_state;
 199        int err;
 200
 201        lock_sock(sk);
 202
 203        err = -EINVAL;
 204        if (sock->state != SS_UNCONNECTED || sock->type != SOCK_STREAM)
 205                goto out;
 206
 207        old_state = sk->sk_state;
 208        if (!((1 << old_state) & (TCPF_CLOSE | TCPF_LISTEN)))
 209                goto out;
 210
 211        /* Really, if the socket is already in listen state
 212         * we can only allow the backlog to be adjusted.
 213         */
 214        if (old_state != TCP_LISTEN) {
 215                /* Check special setups for testing purpose to enable TFO w/o
 216                 * requiring TCP_FASTOPEN sockopt.
 217                 * Note that only TCP sockets (SOCK_STREAM) will reach here.
 218                 * Also fastopenq may already been allocated because this
 219                 * socket was in TCP_LISTEN state previously but was
 220                 * shutdown() (rather than close()).
 221                 */
 222                if ((sysctl_tcp_fastopen & TFO_SERVER_ENABLE) != 0 &&
 223                    inet_csk(sk)->icsk_accept_queue.fastopenq == NULL) {
 224                        if ((sysctl_tcp_fastopen & TFO_SERVER_WO_SOCKOPT1) != 0)
 225                                err = fastopen_init_queue(sk, backlog);
 226                        else if ((sysctl_tcp_fastopen &
 227                                  TFO_SERVER_WO_SOCKOPT2) != 0)
 228                                err = fastopen_init_queue(sk,
 229                                    ((uint)sysctl_tcp_fastopen) >> 16);
 230                        else
 231                                err = 0;
 232                        if (err)
 233                                goto out;
 234                }
 235                err = inet_csk_listen_start(sk, backlog);
 236                if (err)
 237                        goto out;
 238        }
 239        sk->sk_max_ack_backlog = backlog;
 240        err = 0;
 241
 242out:
 243        release_sock(sk);
 244        return err;
 245}
 246EXPORT_SYMBOL(inet_listen);
 247
 248u32 inet_ehash_secret __read_mostly;
 249EXPORT_SYMBOL(inet_ehash_secret);
 250
 251/*
 252 * inet_ehash_secret must be set exactly once
 253 */
 254void build_ehash_secret(void)
 255{
 256        u32 rnd;
 257
 258        do {
 259                get_random_bytes(&rnd, sizeof(rnd));
 260        } while (rnd == 0);
 261
 262        cmpxchg(&inet_ehash_secret, 0, rnd);
 263}
 264EXPORT_SYMBOL(build_ehash_secret);
 265
 266static inline int inet_netns_ok(struct net *net, __u8 protocol)
 267{
 268        const struct net_protocol *ipprot;
 269
 270        if (net_eq(net, &init_net))
 271                return 1;
 272
 273        ipprot = rcu_dereference(inet_protos[protocol]);
 274        if (ipprot == NULL) {
 275                /* raw IP is OK */
 276                return 1;
 277        }
 278        return ipprot->netns_ok;
 279}
 280
 281/*
 282 *      Create an inet socket.
 283 */
 284
 285static int inet_create(struct net *net, struct socket *sock, int protocol,
 286                       int kern)
 287{
 288        struct sock *sk;
 289        struct inet_protosw *answer;
 290        struct inet_sock *inet;
 291        struct proto *answer_prot;
 292        unsigned char answer_flags;
 293        char answer_no_check;
 294        int try_loading_module = 0;
 295        int err;
 296
 297        if (unlikely(!inet_ehash_secret))
 298                if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM)
 299                        build_ehash_secret();
 300
 301        sock->state = SS_UNCONNECTED;
 302
 303        /* Look for the requested type/protocol pair. */
 304lookup_protocol:
 305        err = -ESOCKTNOSUPPORT;
 306        rcu_read_lock();
 307        list_for_each_entry_rcu(answer, &inetsw[sock->type], list) {
 308
 309                err = 0;
 310                /* Check the non-wild match. */
 311                if (protocol == answer->protocol) {
 312                        if (protocol != IPPROTO_IP)
 313                                break;
 314                } else {
 315                        /* Check for the two wild cases. */
 316                        if (IPPROTO_IP == protocol) {
 317                                protocol = answer->protocol;
 318                                break;
 319                        }
 320                        if (IPPROTO_IP == answer->protocol)
 321                                break;
 322                }
 323                err = -EPROTONOSUPPORT;
 324        }
 325
 326        if (unlikely(err)) {
 327                if (try_loading_module < 2) {
 328                        rcu_read_unlock();
 329                        /*
 330                         * Be more specific, e.g. net-pf-2-proto-132-type-1
 331                         * (net-pf-PF_INET-proto-IPPROTO_SCTP-type-SOCK_STREAM)
 332                         */
 333                        if (++try_loading_module == 1)
 334                                request_module("net-pf-%d-proto-%d-type-%d",
 335                                               PF_INET, protocol, sock->type);
 336                        /*
 337                         * Fall back to generic, e.g. net-pf-2-proto-132
 338                         * (net-pf-PF_INET-proto-IPPROTO_SCTP)
 339                         */
 340                        else
 341                                request_module("net-pf-%d-proto-%d",
 342                                               PF_INET, protocol);
 343                        goto lookup_protocol;
 344                } else
 345                        goto out_rcu_unlock;
 346        }
 347
 348        err = -EPERM;
 349        if (sock->type == SOCK_RAW && !kern && !capable(CAP_NET_RAW))
 350                goto out_rcu_unlock;
 351
 352        err = -EAFNOSUPPORT;
 353        if (!inet_netns_ok(net, protocol))
 354                goto out_rcu_unlock;
 355
 356        sock->ops = answer->ops;
 357        answer_prot = answer->prot;
 358        answer_no_check = answer->no_check;
 359        answer_flags = answer->flags;
 360        rcu_read_unlock();
 361
 362        WARN_ON(answer_prot->slab == NULL);
 363
 364        err = -ENOBUFS;
 365        sk = sk_alloc(net, PF_INET, GFP_KERNEL, answer_prot);
 366        if (sk == NULL)
 367                goto out;
 368
 369        err = 0;
 370        sk->sk_no_check = answer_no_check;
 371        if (INET_PROTOSW_REUSE & answer_flags)
 372                sk->sk_reuse = SK_CAN_REUSE;
 373
 374        inet = inet_sk(sk);
 375        inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
 376
 377        inet->nodefrag = 0;
 378
 379        if (SOCK_RAW == sock->type) {
 380                inet->inet_num = protocol;
 381                if (IPPROTO_RAW == protocol)
 382                        inet->hdrincl = 1;
 383        }
 384
 385        if (ipv4_config.no_pmtu_disc)
 386                inet->pmtudisc = IP_PMTUDISC_DONT;
 387        else
 388                inet->pmtudisc = IP_PMTUDISC_WANT;
 389
 390        inet->inet_id = 0;
 391
 392        sock_init_data(sock, sk);
 393
 394        sk->sk_destruct    = inet_sock_destruct;
 395        sk->sk_protocol    = protocol;
 396        sk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
 397
 398        inet->uc_ttl    = -1;
 399        inet->mc_loop   = 1;
 400        inet->mc_ttl    = 1;
 401        inet->mc_all    = 1;
 402        inet->mc_index  = 0;
 403        inet->mc_list   = NULL;
 404        inet->rcv_tos   = 0;
 405
 406        sk_refcnt_debug_inc(sk);
 407
 408        if (inet->inet_num) {
 409                /* It assumes that any protocol which allows
 410                 * the user to assign a number at socket
 411                 * creation time automatically
 412                 * shares.
 413                 */
 414                inet->inet_sport = htons(inet->inet_num);
 415                /* Add to protocol hash chains. */
 416                sk->sk_prot->hash(sk);
 417        }
 418
 419        if (sk->sk_prot->init) {
 420                err = sk->sk_prot->init(sk);
 421                if (err)
 422                        sk_common_release(sk);
 423        }
 424out:
 425        return err;
 426out_rcu_unlock:
 427        rcu_read_unlock();
 428        goto out;
 429}
 430
 431
 432/*
 433 *      The peer socket should always be NULL (or else). When we call this
 434 *      function we are destroying the object and from then on nobody
 435 *      should refer to it.
 436 */
 437int inet_release(struct socket *sock)
 438{
 439        struct sock *sk = sock->sk;
 440
 441        if (sk) {
 442                long timeout;
 443
 444                sock_rps_reset_flow(sk);
 445
 446                /* Applications forget to leave groups before exiting */
 447                ip_mc_drop_socket(sk);
 448
 449                /* If linger is set, we don't return until the close
 450                 * is complete.  Otherwise we return immediately. The
 451                 * actually closing is done the same either way.
 452                 *
 453                 * If the close is due to the process exiting, we never
 454                 * linger..
 455                 */
 456                timeout = 0;
 457                if (sock_flag(sk, SOCK_LINGER) &&
 458                    !(current->flags & PF_EXITING))
 459                        timeout = sk->sk_lingertime;
 460                sock->sk = NULL;
 461                sk->sk_prot->close(sk, timeout);
 462        }
 463        return 0;
 464}
 465EXPORT_SYMBOL(inet_release);
 466
 467/* It is off by default, see below. */
 468int sysctl_ip_nonlocal_bind __read_mostly;
 469EXPORT_SYMBOL(sysctl_ip_nonlocal_bind);
 470
 471int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 472{
 473        struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
 474        struct sock *sk = sock->sk;
 475        struct inet_sock *inet = inet_sk(sk);
 476        unsigned short snum;
 477        int chk_addr_ret;
 478        int err;
 479
 480        /* If the socket has its own bind function then use it. (RAW) */
 481        if (sk->sk_prot->bind) {
 482                err = sk->sk_prot->bind(sk, uaddr, addr_len);
 483                goto out;
 484        }
 485        err = -EINVAL;
 486        if (addr_len < sizeof(struct sockaddr_in))
 487                goto out;
 488
 489        if (addr->sin_family != AF_INET) {
 490                /* Compatibility games : accept AF_UNSPEC (mapped to AF_INET)
 491                 * only if s_addr is INADDR_ANY.
 492                 */
 493                err = -EAFNOSUPPORT;
 494                if (addr->sin_family != AF_UNSPEC ||
 495                    addr->sin_addr.s_addr != htonl(INADDR_ANY))
 496                        goto out;
 497        }
 498
 499        chk_addr_ret = inet_addr_type(sock_net(sk), addr->sin_addr.s_addr);
 500
 501        /* Not specified by any standard per-se, however it breaks too
 502         * many applications when removed.  It is unfortunate since
 503         * allowing applications to make a non-local bind solves
 504         * several problems with systems using dynamic addressing.
 505         * (ie. your servers still start up even if your ISDN link
 506         *  is temporarily down)
 507         */
 508        err = -EADDRNOTAVAIL;
 509        if (!sysctl_ip_nonlocal_bind &&
 510            !(inet->freebind || inet->transparent) &&
 511            addr->sin_addr.s_addr != htonl(INADDR_ANY) &&
 512            chk_addr_ret != RTN_LOCAL &&
 513            chk_addr_ret != RTN_MULTICAST &&
 514            chk_addr_ret != RTN_BROADCAST)
 515                goto out;
 516
 517        snum = ntohs(addr->sin_port);
 518        err = -EACCES;
 519        if (snum && snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
 520                goto out;
 521
 522        /*      We keep a pair of addresses. rcv_saddr is the one
 523         *      used by hash lookups, and saddr is used for transmit.
 524         *
 525         *      In the BSD API these are the same except where it
 526         *      would be illegal to use them (multicast/broadcast) in
 527         *      which case the sending device address is used.
 528         */
 529        lock_sock(sk);
 530
 531        /* Check these errors (active socket, double bind). */
 532        err = -EINVAL;
 533        if (sk->sk_state != TCP_CLOSE || inet->inet_num)
 534                goto out_release_sock;
 535
 536        inet->inet_rcv_saddr = inet->inet_saddr = addr->sin_addr.s_addr;
 537        if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST)
 538                inet->inet_saddr = 0;  /* Use device */
 539
 540        /* Make sure we are allowed to bind here. */
 541        if (sk->sk_prot->get_port(sk, snum)) {
 542                inet->inet_saddr = inet->inet_rcv_saddr = 0;
 543                err = -EADDRINUSE;
 544                goto out_release_sock;
 545        }
 546
 547        if (inet->inet_rcv_saddr)
 548                sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
 549        if (snum)
 550                sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
 551        inet->inet_sport = htons(inet->inet_num);
 552        inet->inet_daddr = 0;
 553        inet->inet_dport = 0;
 554        sk_dst_reset(sk);
 555        err = 0;
 556out_release_sock:
 557        release_sock(sk);
 558out:
 559        return err;
 560}
 561EXPORT_SYMBOL(inet_bind);
 562
 563int inet_dgram_connect(struct socket *sock, struct sockaddr *uaddr,
 564                       int addr_len, int flags)
 565{
 566        struct sock *sk = sock->sk;
 567
 568        if (addr_len < sizeof(uaddr->sa_family))
 569                return -EINVAL;
 570        if (uaddr->sa_family == AF_UNSPEC)
 571                return sk->sk_prot->disconnect(sk, flags);
 572
 573        if (!inet_sk(sk)->inet_num && inet_autobind(sk))
 574                return -EAGAIN;
 575        return sk->sk_prot->connect(sk, uaddr, addr_len);
 576}
 577EXPORT_SYMBOL(inet_dgram_connect);
 578
 579static long inet_wait_for_connect(struct sock *sk, long timeo, int writebias)
 580{
 581        DEFINE_WAIT(wait);
 582
 583        prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
 584        sk->sk_write_pending += writebias;
 585
 586        /* Basic assumption: if someone sets sk->sk_err, he _must_
 587         * change state of the socket from TCP_SYN_*.
 588         * Connect() does not allow to get error notifications
 589         * without closing the socket.
 590         */
 591        while ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
 592                release_sock(sk);
 593                timeo = schedule_timeout(timeo);
 594                lock_sock(sk);
 595                if (signal_pending(current) || !timeo)
 596                        break;
 597                prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
 598        }
 599        finish_wait(sk_sleep(sk), &wait);
 600        sk->sk_write_pending -= writebias;
 601        return timeo;
 602}
 603
 604/*
 605 *      Connect to a remote host. There is regrettably still a little
 606 *      TCP 'magic' in here.
 607 */
 608int __inet_stream_connect(struct socket *sock, struct sockaddr *uaddr,
 609                          int addr_len, int flags)
 610{
 611        struct sock *sk = sock->sk;
 612        int err;
 613        long timeo;
 614
 615        if (addr_len < sizeof(uaddr->sa_family))
 616                return -EINVAL;
 617
 618        if (uaddr->sa_family == AF_UNSPEC) {
 619                err = sk->sk_prot->disconnect(sk, flags);
 620                sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
 621                goto out;
 622        }
 623
 624        switch (sock->state) {
 625        default:
 626                err = -EINVAL;
 627                goto out;
 628        case SS_CONNECTED:
 629                err = -EISCONN;
 630                goto out;
 631        case SS_CONNECTING:
 632                err = -EALREADY;
 633                /* Fall out of switch with err, set for this state */
 634                break;
 635        case SS_UNCONNECTED:
 636                err = -EISCONN;
 637                if (sk->sk_state != TCP_CLOSE)
 638                        goto out;
 639
 640                err = sk->sk_prot->connect(sk, uaddr, addr_len);
 641                if (err < 0)
 642                        goto out;
 643
 644                sock->state = SS_CONNECTING;
 645
 646                /* Just entered SS_CONNECTING state; the only
 647                 * difference is that return value in non-blocking
 648                 * case is EINPROGRESS, rather than EALREADY.
 649                 */
 650                err = -EINPROGRESS;
 651                break;
 652        }
 653
 654        timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
 655
 656        if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
 657                int writebias = (sk->sk_protocol == IPPROTO_TCP) &&
 658                                tcp_sk(sk)->fastopen_req &&
 659                                tcp_sk(sk)->fastopen_req->data ? 1 : 0;
 660
 661                /* Error code is set above */
 662                if (!timeo || !inet_wait_for_connect(sk, timeo, writebias))
 663                        goto out;
 664
 665                err = sock_intr_errno(timeo);
 666                if (signal_pending(current))
 667                        goto out;
 668        }
 669
 670        /* Connection was closed by RST, timeout, ICMP error
 671         * or another process disconnected us.
 672         */
 673        if (sk->sk_state == TCP_CLOSE)
 674                goto sock_error;
 675
 676        /* sk->sk_err may be not zero now, if RECVERR was ordered by user
 677         * and error was received after socket entered established state.
 678         * Hence, it is handled normally after connect() return successfully.
 679         */
 680
 681        sock->state = SS_CONNECTED;
 682        err = 0;
 683out:
 684        return err;
 685
 686sock_error:
 687        err = sock_error(sk) ? : -ECONNABORTED;
 688        sock->state = SS_UNCONNECTED;
 689        if (sk->sk_prot->disconnect(sk, flags))
 690                sock->state = SS_DISCONNECTING;
 691        goto out;
 692}
 693EXPORT_SYMBOL(__inet_stream_connect);
 694
 695int inet_stream_connect(struct socket *sock, struct sockaddr *uaddr,
 696                        int addr_len, int flags)
 697{
 698        int err;
 699
 700        lock_sock(sock->sk);
 701        err = __inet_stream_connect(sock, uaddr, addr_len, flags);
 702        release_sock(sock->sk);
 703        return err;
 704}
 705EXPORT_SYMBOL(inet_stream_connect);
 706
 707/*
 708 *      Accept a pending connection. The TCP layer now gives BSD semantics.
 709 */
 710
 711int inet_accept(struct socket *sock, struct socket *newsock, int flags)
 712{
 713        struct sock *sk1 = sock->sk;
 714        int err = -EINVAL;
 715        struct sock *sk2 = sk1->sk_prot->accept(sk1, flags, &err);
 716
 717        if (!sk2)
 718                goto do_err;
 719
 720        lock_sock(sk2);
 721
 722        sock_rps_record_flow(sk2);
 723        WARN_ON(!((1 << sk2->sk_state) &
 724                  (TCPF_ESTABLISHED | TCPF_SYN_RECV |
 725                  TCPF_CLOSE_WAIT | TCPF_CLOSE)));
 726
 727        sock_graft(sk2, newsock);
 728
 729        newsock->state = SS_CONNECTED;
 730        err = 0;
 731        release_sock(sk2);
 732do_err:
 733        return err;
 734}
 735EXPORT_SYMBOL(inet_accept);
 736
 737
 738/*
 739 *      This does both peername and sockname.
 740 */
 741int inet_getname(struct socket *sock, struct sockaddr *uaddr,
 742                        int *uaddr_len, int peer)
 743{
 744        struct sock *sk         = sock->sk;
 745        struct inet_sock *inet  = inet_sk(sk);
 746        DECLARE_SOCKADDR(struct sockaddr_in *, sin, uaddr);
 747
 748        sin->sin_family = AF_INET;
 749        if (peer) {
 750                if (!inet->inet_dport ||
 751                    (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
 752                     peer == 1))
 753                        return -ENOTCONN;
 754                sin->sin_port = inet->inet_dport;
 755                sin->sin_addr.s_addr = inet->inet_daddr;
 756        } else {
 757                __be32 addr = inet->inet_rcv_saddr;
 758                if (!addr)
 759                        addr = inet->inet_saddr;
 760                sin->sin_port = inet->inet_sport;
 761                sin->sin_addr.s_addr = addr;
 762        }
 763        memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
 764        *uaddr_len = sizeof(*sin);
 765        return 0;
 766}
 767EXPORT_SYMBOL(inet_getname);
 768
 769int inet_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
 770                 size_t size)
 771{
 772        struct sock *sk = sock->sk;
 773
 774        sock_rps_record_flow(sk);
 775
 776        /* We may need to bind the socket. */
 777        if (!inet_sk(sk)->inet_num && !sk->sk_prot->no_autobind &&
 778            inet_autobind(sk))
 779                return -EAGAIN;
 780
 781        return sk->sk_prot->sendmsg(iocb, sk, msg, size);
 782}
 783EXPORT_SYMBOL(inet_sendmsg);
 784
 785ssize_t inet_sendpage(struct socket *sock, struct page *page, int offset,
 786                      size_t size, int flags)
 787{
 788        struct sock *sk = sock->sk;
 789
 790        sock_rps_record_flow(sk);
 791
 792        /* We may need to bind the socket. */
 793        if (!inet_sk(sk)->inet_num && !sk->sk_prot->no_autobind &&
 794            inet_autobind(sk))
 795                return -EAGAIN;
 796
 797        if (sk->sk_prot->sendpage)
 798                return sk->sk_prot->sendpage(sk, page, offset, size, flags);
 799        return sock_no_sendpage(sock, page, offset, size, flags);
 800}
 801EXPORT_SYMBOL(inet_sendpage);
 802
 803int inet_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
 804                 size_t size, int flags)
 805{
 806        struct sock *sk = sock->sk;
 807        int addr_len = 0;
 808        int err;
 809
 810        sock_rps_record_flow(sk);
 811
 812        err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT,
 813                                   flags & ~MSG_DONTWAIT, &addr_len);
 814        if (err >= 0)
 815                msg->msg_namelen = addr_len;
 816        return err;
 817}
 818EXPORT_SYMBOL(inet_recvmsg);
 819
 820int inet_shutdown(struct socket *sock, int how)
 821{
 822        struct sock *sk = sock->sk;
 823        int err = 0;
 824
 825        /* This should really check to make sure
 826         * the socket is a TCP socket. (WHY AC...)
 827         */
 828        how++; /* maps 0->1 has the advantage of making bit 1 rcvs and
 829                       1->2 bit 2 snds.
 830                       2->3 */
 831        if ((how & ~SHUTDOWN_MASK) || !how)     /* MAXINT->0 */
 832                return -EINVAL;
 833
 834        lock_sock(sk);
 835        if (sock->state == SS_CONNECTING) {
 836                if ((1 << sk->sk_state) &
 837                    (TCPF_SYN_SENT | TCPF_SYN_RECV | TCPF_CLOSE))
 838                        sock->state = SS_DISCONNECTING;
 839                else
 840                        sock->state = SS_CONNECTED;
 841        }
 842
 843        switch (sk->sk_state) {
 844        case TCP_CLOSE:
 845                err = -ENOTCONN;
 846                /* Hack to wake up other listeners, who can poll for
 847                   POLLHUP, even on eg. unconnected UDP sockets -- RR */
 848        default:
 849                sk->sk_shutdown |= how;
 850                if (sk->sk_prot->shutdown)
 851                        sk->sk_prot->shutdown(sk, how);
 852                break;
 853
 854        /* Remaining two branches are temporary solution for missing
 855         * close() in multithreaded environment. It is _not_ a good idea,
 856         * but we have no choice until close() is repaired at VFS level.
 857         */
 858        case TCP_LISTEN:
 859                if (!(how & RCV_SHUTDOWN))
 860                        break;
 861                /* Fall through */
 862        case TCP_SYN_SENT:
 863                err = sk->sk_prot->disconnect(sk, O_NONBLOCK);
 864                sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
 865                break;
 866        }
 867
 868        /* Wake up anyone sleeping in poll. */
 869        sk->sk_state_change(sk);
 870        release_sock(sk);
 871        return err;
 872}
 873EXPORT_SYMBOL(inet_shutdown);
 874
 875/*
 876 *      ioctl() calls you can issue on an INET socket. Most of these are
 877 *      device configuration and stuff and very rarely used. Some ioctls
 878 *      pass on to the socket itself.
 879 *
 880 *      NOTE: I like the idea of a module for the config stuff. ie ifconfig
 881 *      loads the devconfigure module does its configuring and unloads it.
 882 *      There's a good 20K of config code hanging around the kernel.
 883 */
 884
 885int inet_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 886{
 887        struct sock *sk = sock->sk;
 888        int err = 0;
 889        struct net *net = sock_net(sk);
 890
 891        switch (cmd) {
 892        case SIOCGSTAMP:
 893                err = sock_get_timestamp(sk, (struct timeval __user *)arg);
 894                break;
 895        case SIOCGSTAMPNS:
 896                err = sock_get_timestampns(sk, (struct timespec __user *)arg);
 897                break;
 898        case SIOCADDRT:
 899        case SIOCDELRT:
 900        case SIOCRTMSG:
 901                err = ip_rt_ioctl(net, cmd, (void __user *)arg);
 902                break;
 903        case SIOCDARP:
 904        case SIOCGARP:
 905        case SIOCSARP:
 906                err = arp_ioctl(net, cmd, (void __user *)arg);
 907                break;
 908        case SIOCGIFADDR:
 909        case SIOCSIFADDR:
 910        case SIOCGIFBRDADDR:
 911        case SIOCSIFBRDADDR:
 912        case SIOCGIFNETMASK:
 913        case SIOCSIFNETMASK:
 914        case SIOCGIFDSTADDR:
 915        case SIOCSIFDSTADDR:
 916        case SIOCSIFPFLAGS:
 917        case SIOCGIFPFLAGS:
 918        case SIOCSIFFLAGS:
 919                err = devinet_ioctl(net, cmd, (void __user *)arg);
 920                break;
 921        default:
 922                if (sk->sk_prot->ioctl)
 923                        err = sk->sk_prot->ioctl(sk, cmd, arg);
 924                else
 925                        err = -ENOIOCTLCMD;
 926                break;
 927        }
 928        return err;
 929}
 930EXPORT_SYMBOL(inet_ioctl);
 931
 932#ifdef CONFIG_COMPAT
 933static int inet_compat_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 934{
 935        struct sock *sk = sock->sk;
 936        int err = -ENOIOCTLCMD;
 937
 938        if (sk->sk_prot->compat_ioctl)
 939                err = sk->sk_prot->compat_ioctl(sk, cmd, arg);
 940
 941        return err;
 942}
 943#endif
 944
 945const struct proto_ops inet_stream_ops = {
 946        .family            = PF_INET,
 947        .owner             = THIS_MODULE,
 948        .release           = inet_release,
 949        .bind              = inet_bind,
 950        .connect           = inet_stream_connect,
 951        .socketpair        = sock_no_socketpair,
 952        .accept            = inet_accept,
 953        .getname           = inet_getname,
 954        .poll              = tcp_poll,
 955        .ioctl             = inet_ioctl,
 956        .listen            = inet_listen,
 957        .shutdown          = inet_shutdown,
 958        .setsockopt        = sock_common_setsockopt,
 959        .getsockopt        = sock_common_getsockopt,
 960        .sendmsg           = inet_sendmsg,
 961        .recvmsg           = inet_recvmsg,
 962        .mmap              = sock_no_mmap,
 963        .sendpage          = inet_sendpage,
 964        .splice_read       = tcp_splice_read,
 965#ifdef CONFIG_COMPAT
 966        .compat_setsockopt = compat_sock_common_setsockopt,
 967        .compat_getsockopt = compat_sock_common_getsockopt,
 968        .compat_ioctl      = inet_compat_ioctl,
 969#endif
 970};
 971EXPORT_SYMBOL(inet_stream_ops);
 972
 973const struct proto_ops inet_dgram_ops = {
 974        .family            = PF_INET,
 975        .owner             = THIS_MODULE,
 976        .release           = inet_release,
 977        .bind              = inet_bind,
 978        .connect           = inet_dgram_connect,
 979        .socketpair        = sock_no_socketpair,
 980        .accept            = sock_no_accept,
 981        .getname           = inet_getname,
 982        .poll              = udp_poll,
 983        .ioctl             = inet_ioctl,
 984        .listen            = sock_no_listen,
 985        .shutdown          = inet_shutdown,
 986        .setsockopt        = sock_common_setsockopt,
 987        .getsockopt        = sock_common_getsockopt,
 988        .sendmsg           = inet_sendmsg,
 989        .recvmsg           = inet_recvmsg,
 990        .mmap              = sock_no_mmap,
 991        .sendpage          = inet_sendpage,
 992#ifdef CONFIG_COMPAT
 993        .compat_setsockopt = compat_sock_common_setsockopt,
 994        .compat_getsockopt = compat_sock_common_getsockopt,
 995        .compat_ioctl      = inet_compat_ioctl,
 996#endif
 997};
 998EXPORT_SYMBOL(inet_dgram_ops);
 999
1000/*
1001 * For SOCK_RAW sockets; should be the same as inet_dgram_ops but without
1002 * udp_poll
1003 */
1004static const struct proto_ops inet_sockraw_ops = {
1005        .family            = PF_INET,
1006        .owner             = THIS_MODULE,
1007        .release           = inet_release,
1008        .bind              = inet_bind,
1009        .connect           = inet_dgram_connect,
1010        .socketpair        = sock_no_socketpair,
1011        .accept            = sock_no_accept,
1012        .getname           = inet_getname,
1013        .poll              = datagram_poll,
1014        .ioctl             = inet_ioctl,
1015        .listen            = sock_no_listen,
1016        .shutdown          = inet_shutdown,
1017        .setsockopt        = sock_common_setsockopt,
1018        .getsockopt        = sock_common_getsockopt,
1019        .sendmsg           = inet_sendmsg,
1020        .recvmsg           = inet_recvmsg,
1021        .mmap              = sock_no_mmap,
1022        .sendpage          = inet_sendpage,
1023#ifdef CONFIG_COMPAT
1024        .compat_setsockopt = compat_sock_common_setsockopt,
1025        .compat_getsockopt = compat_sock_common_getsockopt,
1026        .compat_ioctl      = inet_compat_ioctl,
1027#endif
1028};
1029
1030static const struct net_proto_family inet_family_ops = {
1031        .family = PF_INET,
1032        .create = inet_create,
1033        .owner  = THIS_MODULE,
1034};
1035
1036/* Upon startup we insert all the elements in inetsw_array[] into
1037 * the linked list inetsw.
1038 */
1039static struct inet_protosw inetsw_array[] =
1040{
1041        {
1042                .type =       SOCK_STREAM,
1043                .protocol =   IPPROTO_TCP,
1044                .prot =       &tcp_prot,
1045                .ops =        &inet_stream_ops,
1046                .no_check =   0,
1047                .flags =      INET_PROTOSW_PERMANENT |
1048                              INET_PROTOSW_ICSK,
1049        },
1050
1051        {
1052                .type =       SOCK_DGRAM,
1053                .protocol =   IPPROTO_UDP,
1054                .prot =       &udp_prot,
1055                .ops =        &inet_dgram_ops,
1056                .no_check =   UDP_CSUM_DEFAULT,
1057                .flags =      INET_PROTOSW_PERMANENT,
1058       },
1059
1060       {
1061                .type =       SOCK_DGRAM,
1062                .protocol =   IPPROTO_ICMP,
1063                .prot =       &ping_prot,
1064                .ops =        &inet_dgram_ops,
1065                .no_check =   UDP_CSUM_DEFAULT,
1066                .flags =      INET_PROTOSW_REUSE,
1067       },
1068
1069       {
1070               .type =       SOCK_RAW,
1071               .protocol =   IPPROTO_IP,        /* wild card */
1072               .prot =       &raw_prot,
1073               .ops =        &inet_sockraw_ops,
1074               .no_check =   UDP_CSUM_DEFAULT,
1075               .flags =      INET_PROTOSW_REUSE,
1076       }
1077};
1078
1079#define INETSW_ARRAY_LEN ARRAY_SIZE(inetsw_array)
1080
1081void inet_register_protosw(struct inet_protosw *p)
1082{
1083        struct list_head *lh;
1084        struct inet_protosw *answer;
1085        int protocol = p->protocol;
1086        struct list_head *last_perm;
1087
1088        spin_lock_bh(&inetsw_lock);
1089
1090        if (p->type >= SOCK_MAX)
1091                goto out_illegal;
1092
1093        /* If we are trying to override a permanent protocol, bail. */
1094        answer = NULL;
1095        last_perm = &inetsw[p->type];
1096        list_for_each(lh, &inetsw[p->type]) {
1097                answer = list_entry(lh, struct inet_protosw, list);
1098
1099                /* Check only the non-wild match. */
1100                if (INET_PROTOSW_PERMANENT & answer->flags) {
1101                        if (protocol == answer->protocol)
1102                                break;
1103                        last_perm = lh;
1104                }
1105
1106                answer = NULL;
1107        }
1108        if (answer)
1109                goto out_permanent;
1110
1111        /* Add the new entry after the last permanent entry if any, so that
1112         * the new entry does not override a permanent entry when matched with
1113         * a wild-card protocol. But it is allowed to override any existing
1114         * non-permanent entry.  This means that when we remove this entry, the
1115         * system automatically returns to the old behavior.
1116         */
1117        list_add_rcu(&p->list, last_perm);
1118out:
1119        spin_unlock_bh(&inetsw_lock);
1120
1121        return;
1122
1123out_permanent:
1124        pr_err("Attempt to override permanent protocol %d\n", protocol);
1125        goto out;
1126
1127out_illegal:
1128        pr_err("Ignoring attempt to register invalid socket type %d\n",
1129               p->type);
1130        goto out;
1131}
1132EXPORT_SYMBOL(inet_register_protosw);
1133
1134void inet_unregister_protosw(struct inet_protosw *p)
1135{
1136        if (INET_PROTOSW_PERMANENT & p->flags) {
1137                pr_err("Attempt to unregister permanent protocol %d\n",
1138                       p->protocol);
1139        } else {
1140                spin_lock_bh(&inetsw_lock);
1141                list_del_rcu(&p->list);
1142                spin_unlock_bh(&inetsw_lock);
1143
1144                synchronize_net();
1145        }
1146}
1147EXPORT_SYMBOL(inet_unregister_protosw);
1148
1149/*
1150 *      Shall we try to damage output packets if routing dev changes?
1151 */
1152
1153int sysctl_ip_dynaddr __read_mostly;
1154
1155static int inet_sk_reselect_saddr(struct sock *sk)
1156{
1157        struct inet_sock *inet = inet_sk(sk);
1158        __be32 old_saddr = inet->inet_saddr;
1159        __be32 daddr = inet->inet_daddr;
1160        struct flowi4 *fl4;
1161        struct rtable *rt;
1162        __be32 new_saddr;
1163        struct ip_options_rcu *inet_opt;
1164
1165        inet_opt = rcu_dereference_protected(inet->inet_opt,
1166                                             sock_owned_by_user(sk));
1167        if (inet_opt && inet_opt->opt.srr)
1168                daddr = inet_opt->opt.faddr;
1169
1170        /* Query new route. */
1171        fl4 = &inet->cork.fl.u.ip4;
1172        rt = ip_route_connect(fl4, daddr, 0, RT_CONN_FLAGS(sk),
1173                              sk->sk_bound_dev_if, sk->sk_protocol,
1174                              inet->inet_sport, inet->inet_dport, sk, false);
1175        if (IS_ERR(rt))
1176                return PTR_ERR(rt);
1177
1178        sk_setup_caps(sk, &rt->dst);
1179
1180        new_saddr = fl4->saddr;
1181
1182        if (new_saddr == old_saddr)
1183                return 0;
1184
1185        if (sysctl_ip_dynaddr > 1) {
1186                pr_info("%s(): shifting inet->saddr from %pI4 to %pI4\n",
1187                        __func__, &old_saddr, &new_saddr);
1188        }
1189
1190        inet->inet_saddr = inet->inet_rcv_saddr = new_saddr;
1191
1192        /*
1193         * XXX The only one ugly spot where we need to
1194         * XXX really change the sockets identity after
1195         * XXX it has entered the hashes. -DaveM
1196         *
1197         * Besides that, it does not check for connection
1198         * uniqueness. Wait for troubles.
1199         */
1200        __sk_prot_rehash(sk);
1201        return 0;
1202}
1203
1204int inet_sk_rebuild_header(struct sock *sk)
1205{
1206        struct inet_sock *inet = inet_sk(sk);
1207        struct rtable *rt = (struct rtable *)__sk_dst_check(sk, 0);
1208        __be32 daddr;
1209        struct ip_options_rcu *inet_opt;
1210        struct flowi4 *fl4;
1211        int err;
1212
1213        /* Route is OK, nothing to do. */
1214        if (rt)
1215                return 0;
1216
1217        /* Reroute. */
1218        rcu_read_lock();
1219        inet_opt = rcu_dereference(inet->inet_opt);
1220        daddr = inet->inet_daddr;
1221        if (inet_opt && inet_opt->opt.srr)
1222                daddr = inet_opt->opt.faddr;
1223        rcu_read_unlock();
1224        fl4 = &inet->cork.fl.u.ip4;
1225        rt = ip_route_output_ports(sock_net(sk), fl4, sk, daddr, inet->inet_saddr,
1226                                   inet->inet_dport, inet->inet_sport,
1227                                   sk->sk_protocol, RT_CONN_FLAGS(sk),
1228                                   sk->sk_bound_dev_if);
1229        if (!IS_ERR(rt)) {
1230                err = 0;
1231                sk_setup_caps(sk, &rt->dst);
1232        } else {
1233                err = PTR_ERR(rt);
1234
1235                /* Routing failed... */
1236                sk->sk_route_caps = 0;
1237                /*
1238                 * Other protocols have to map its equivalent state to TCP_SYN_SENT.
1239                 * DCCP maps its DCCP_REQUESTING state to TCP_SYN_SENT. -acme
1240                 */
1241                if (!sysctl_ip_dynaddr ||
1242                    sk->sk_state != TCP_SYN_SENT ||
1243                    (sk->sk_userlocks & SOCK_BINDADDR_LOCK) ||
1244                    (err = inet_sk_reselect_saddr(sk)) != 0)
1245                        sk->sk_err_soft = -err;
1246        }
1247
1248        return err;
1249}
1250EXPORT_SYMBOL(inet_sk_rebuild_header);
1251
1252static int inet_gso_send_check(struct sk_buff *skb)
1253{
1254        const struct net_protocol *ops;
1255        const struct iphdr *iph;
1256        int proto;
1257        int ihl;
1258        int err = -EINVAL;
1259
1260        if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
1261                goto out;
1262
1263        iph = ip_hdr(skb);
1264        ihl = iph->ihl * 4;
1265        if (ihl < sizeof(*iph))
1266                goto out;
1267
1268        if (unlikely(!pskb_may_pull(skb, ihl)))
1269                goto out;
1270
1271        __skb_pull(skb, ihl);
1272        skb_reset_transport_header(skb);
1273        iph = ip_hdr(skb);
1274        proto = iph->protocol;
1275        err = -EPROTONOSUPPORT;
1276
1277        rcu_read_lock();
1278        ops = rcu_dereference(inet_protos[proto]);
1279        if (likely(ops && ops->gso_send_check))
1280                err = ops->gso_send_check(skb);
1281        rcu_read_unlock();
1282
1283out:
1284        return err;
1285}
1286
1287static struct sk_buff *inet_gso_segment(struct sk_buff *skb,
1288        netdev_features_t features)
1289{
1290        struct sk_buff *segs = ERR_PTR(-EINVAL);
1291        const struct net_protocol *ops;
1292        struct iphdr *iph;
1293        int proto;
1294        int ihl;
1295        int id;
1296        unsigned int offset = 0;
1297
1298        if (!(features & NETIF_F_V4_CSUM))
1299                features &= ~NETIF_F_SG;
1300
1301        if (unlikely(skb_shinfo(skb)->gso_type &
1302                     ~(SKB_GSO_TCPV4 |
1303                       SKB_GSO_UDP |
1304                       SKB_GSO_DODGY |
1305                       SKB_GSO_TCP_ECN |
1306                       0)))
1307                goto out;
1308
1309        if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
1310                goto out;
1311
1312        iph = ip_hdr(skb);
1313        ihl = iph->ihl * 4;
1314        if (ihl < sizeof(*iph))
1315                goto out;
1316
1317        if (unlikely(!pskb_may_pull(skb, ihl)))
1318                goto out;
1319
1320        __skb_pull(skb, ihl);
1321        skb_reset_transport_header(skb);
1322        iph = ip_hdr(skb);
1323        id = ntohs(iph->id);
1324        proto = iph->protocol;
1325        segs = ERR_PTR(-EPROTONOSUPPORT);
1326
1327        rcu_read_lock();
1328        ops = rcu_dereference(inet_protos[proto]);
1329        if (likely(ops && ops->gso_segment))
1330                segs = ops->gso_segment(skb, features);
1331        rcu_read_unlock();
1332
1333        if (!segs || IS_ERR(segs))
1334                goto out;
1335
1336        skb = segs;
1337        do {
1338                iph = ip_hdr(skb);
1339                if (proto == IPPROTO_UDP) {
1340                        iph->id = htons(id);
1341                        iph->frag_off = htons(offset >> 3);
1342                        if (skb->next != NULL)
1343                                iph->frag_off |= htons(IP_MF);
1344                        offset += (skb->len - skb->mac_len - iph->ihl * 4);
1345                } else
1346                        iph->id = htons(id++);
1347                iph->tot_len = htons(skb->len - skb->mac_len);
1348                iph->check = 0;
1349                iph->check = ip_fast_csum(skb_network_header(skb), iph->ihl);
1350        } while ((skb = skb->next));
1351
1352out:
1353        return segs;
1354}
1355
1356static struct sk_buff **inet_gro_receive(struct sk_buff **head,
1357                                         struct sk_buff *skb)
1358{
1359        const struct net_protocol *ops;
1360        struct sk_buff **pp = NULL;
1361        struct sk_buff *p;
1362        const struct iphdr *iph;
1363        unsigned int hlen;
1364        unsigned int off;
1365        unsigned int id;
1366        int flush = 1;
1367        int proto;
1368
1369        off = skb_gro_offset(skb);
1370        hlen = off + sizeof(*iph);
1371        iph = skb_gro_header_fast(skb, off);
1372        if (skb_gro_header_hard(skb, hlen)) {
1373                iph = skb_gro_header_slow(skb, hlen, off);
1374                if (unlikely(!iph))
1375                        goto out;
1376        }
1377
1378        proto = iph->protocol;
1379
1380        rcu_read_lock();
1381        ops = rcu_dereference(inet_protos[proto]);
1382        if (!ops || !ops->gro_receive)
1383                goto out_unlock;
1384
1385        if (*(u8 *)iph != 0x45)
1386                goto out_unlock;
1387
1388        if (unlikely(ip_fast_csum((u8 *)iph, 5)))
1389                goto out_unlock;
1390
1391        id = ntohl(*(__be32 *)&iph->id);
1392        flush = (u16)((ntohl(*(__be32 *)iph) ^ skb_gro_len(skb)) | (id ^ IP_DF));
1393        id >>= 16;
1394
1395        for (p = *head; p; p = p->next) {
1396                struct iphdr *iph2;
1397
1398                if (!NAPI_GRO_CB(p)->same_flow)
1399                        continue;
1400
1401                iph2 = ip_hdr(p);
1402
1403                if ((iph->protocol ^ iph2->protocol) |
1404                    ((__force u32)iph->saddr ^ (__force u32)iph2->saddr) |
1405                    ((__force u32)iph->daddr ^ (__force u32)iph2->daddr)) {
1406                        NAPI_GRO_CB(p)->same_flow = 0;
1407                        continue;
1408                }
1409
1410                /* All fields must match except length and checksum. */
1411                NAPI_GRO_CB(p)->flush |=
1412                        (iph->ttl ^ iph2->ttl) |
1413                        (iph->tos ^ iph2->tos) |
1414                        ((u16)(ntohs(iph2->id) + NAPI_GRO_CB(p)->count) ^ id);
1415
1416                NAPI_GRO_CB(p)->flush |= flush;
1417        }
1418
1419        NAPI_GRO_CB(skb)->flush |= flush;
1420        skb_gro_pull(skb, sizeof(*iph));
1421        skb_set_transport_header(skb, skb_gro_offset(skb));
1422
1423        pp = ops->gro_receive(head, skb);
1424
1425out_unlock:
1426        rcu_read_unlock();
1427
1428out:
1429        NAPI_GRO_CB(skb)->flush |= flush;
1430
1431        return pp;
1432}
1433
1434static int inet_gro_complete(struct sk_buff *skb)
1435{
1436        __be16 newlen = htons(skb->len - skb_network_offset(skb));
1437        struct iphdr *iph = ip_hdr(skb);
1438        const struct net_protocol *ops;
1439        int proto = iph->protocol;
1440        int err = -ENOSYS;
1441
1442        csum_replace2(&iph->check, iph->tot_len, newlen);
1443        iph->tot_len = newlen;
1444
1445        rcu_read_lock();
1446        ops = rcu_dereference(inet_protos[proto]);
1447        if (WARN_ON(!ops || !ops->gro_complete))
1448                goto out_unlock;
1449
1450        err = ops->gro_complete(skb);
1451
1452out_unlock:
1453        rcu_read_unlock();
1454
1455        return err;
1456}
1457
1458int inet_ctl_sock_create(struct sock **sk, unsigned short family,
1459                         unsigned short type, unsigned char protocol,
1460                         struct net *net)
1461{
1462        struct socket *sock;
1463        int rc = sock_create_kern(family, type, protocol, &sock);
1464
1465        if (rc == 0) {
1466                *sk = sock->sk;
1467                (*sk)->sk_allocation = GFP_ATOMIC;
1468                /*
1469                 * Unhash it so that IP input processing does not even see it,
1470                 * we do not wish this socket to see incoming packets.
1471                 */
1472                (*sk)->sk_prot->unhash(*sk);
1473
1474                sk_change_net(*sk, net);
1475        }
1476        return rc;
1477}
1478EXPORT_SYMBOL_GPL(inet_ctl_sock_create);
1479
1480unsigned long snmp_fold_field(void __percpu *mib[], int offt)
1481{
1482        unsigned long res = 0;
1483        int i, j;
1484
1485        for_each_possible_cpu(i) {
1486                for (j = 0; j < SNMP_ARRAY_SZ; j++)
1487                        res += *(((unsigned long *) per_cpu_ptr(mib[j], i)) + offt);
1488        }
1489        return res;
1490}
1491EXPORT_SYMBOL_GPL(snmp_fold_field);
1492
1493#if BITS_PER_LONG==32
1494
1495u64 snmp_fold_field64(void __percpu *mib[], int offt, size_t syncp_offset)
1496{
1497        u64 res = 0;
1498        int cpu;
1499
1500        for_each_possible_cpu(cpu) {
1501                void *bhptr;
1502                struct u64_stats_sync *syncp;
1503                u64 v;
1504                unsigned int start;
1505
1506                bhptr = per_cpu_ptr(mib[0], cpu);
1507                syncp = (struct u64_stats_sync *)(bhptr + syncp_offset);
1508                do {
1509                        start = u64_stats_fetch_begin_bh(syncp);
1510                        v = *(((u64 *) bhptr) + offt);
1511                } while (u64_stats_fetch_retry_bh(syncp, start));
1512
1513                res += v;
1514        }
1515        return res;
1516}
1517EXPORT_SYMBOL_GPL(snmp_fold_field64);
1518#endif
1519
1520int snmp_mib_init(void __percpu *ptr[2], size_t mibsize, size_t align)
1521{
1522        BUG_ON(ptr == NULL);
1523        ptr[0] = __alloc_percpu(mibsize, align);
1524        if (!ptr[0])
1525                return -ENOMEM;
1526#if SNMP_ARRAY_SZ == 2
1527        ptr[1] = __alloc_percpu(mibsize, align);
1528        if (!ptr[1]) {
1529                free_percpu(ptr[0]);
1530                ptr[0] = NULL;
1531                return -ENOMEM;
1532        }
1533#endif
1534        return 0;
1535}
1536EXPORT_SYMBOL_GPL(snmp_mib_init);
1537
1538void snmp_mib_free(void __percpu *ptr[SNMP_ARRAY_SZ])
1539{
1540        int i;
1541
1542        BUG_ON(ptr == NULL);
1543        for (i = 0; i < SNMP_ARRAY_SZ; i++) {
1544                free_percpu(ptr[i]);
1545                ptr[i] = NULL;
1546        }
1547}
1548EXPORT_SYMBOL_GPL(snmp_mib_free);
1549
1550#ifdef CONFIG_IP_MULTICAST
1551static const struct net_protocol igmp_protocol = {
1552        .handler =      igmp_rcv,
1553        .netns_ok =     1,
1554};
1555#endif
1556
1557static const struct net_protocol tcp_protocol = {
1558        .early_demux    =       tcp_v4_early_demux,
1559        .handler        =       tcp_v4_rcv,
1560        .err_handler    =       tcp_v4_err,
1561        .gso_send_check =       tcp_v4_gso_send_check,
1562        .gso_segment    =       tcp_tso_segment,
1563        .gro_receive    =       tcp4_gro_receive,
1564        .gro_complete   =       tcp4_gro_complete,
1565        .no_policy      =       1,
1566        .netns_ok       =       1,
1567};
1568
1569static const struct net_protocol udp_protocol = {
1570        .handler =      udp_rcv,
1571        .err_handler =  udp_err,
1572        .gso_send_check = udp4_ufo_send_check,
1573        .gso_segment = udp4_ufo_fragment,
1574        .no_policy =    1,
1575        .netns_ok =     1,
1576};
1577
1578static const struct net_protocol icmp_protocol = {
1579        .handler =      icmp_rcv,
1580        .err_handler =  ping_err,
1581        .no_policy =    1,
1582        .netns_ok =     1,
1583};
1584
1585static __net_init int ipv4_mib_init_net(struct net *net)
1586{
1587        if (snmp_mib_init((void __percpu **)net->mib.tcp_statistics,
1588                          sizeof(struct tcp_mib),
1589                          __alignof__(struct tcp_mib)) < 0)
1590                goto err_tcp_mib;
1591        if (snmp_mib_init((void __percpu **)net->mib.ip_statistics,
1592                          sizeof(struct ipstats_mib),
1593                          __alignof__(struct ipstats_mib)) < 0)
1594                goto err_ip_mib;
1595        if (snmp_mib_init((void __percpu **)net->mib.net_statistics,
1596                          sizeof(struct linux_mib),
1597                          __alignof__(struct linux_mib)) < 0)
1598                goto err_net_mib;
1599        if (snmp_mib_init((void __percpu **)net->mib.udp_statistics,
1600                          sizeof(struct udp_mib),
1601                          __alignof__(struct udp_mib)) < 0)
1602                goto err_udp_mib;
1603        if (snmp_mib_init((void __percpu **)net->mib.udplite_statistics,
1604                          sizeof(struct udp_mib),
1605                          __alignof__(struct udp_mib)) < 0)
1606                goto err_udplite_mib;
1607        if (snmp_mib_init((void __percpu **)net->mib.icmp_statistics,
1608                          sizeof(struct icmp_mib),
1609                          __alignof__(struct icmp_mib)) < 0)
1610                goto err_icmp_mib;
1611        net->mib.icmpmsg_statistics = kzalloc(sizeof(struct icmpmsg_mib),
1612                                              GFP_KERNEL);
1613        if (!net->mib.icmpmsg_statistics)
1614                goto err_icmpmsg_mib;
1615
1616        tcp_mib_init(net);
1617        return 0;
1618
1619err_icmpmsg_mib:
1620        snmp_mib_free((void __percpu **)net->mib.icmp_statistics);
1621err_icmp_mib:
1622        snmp_mib_free((void __percpu **)net->mib.udplite_statistics);
1623err_udplite_mib:
1624        snmp_mib_free((void __percpu **)net->mib.udp_statistics);
1625err_udp_mib:
1626        snmp_mib_free((void __percpu **)net->mib.net_statistics);
1627err_net_mib:
1628        snmp_mib_free((void __percpu **)net->mib.ip_statistics);
1629err_ip_mib:
1630        snmp_mib_free((void __percpu **)net->mib.tcp_statistics);
1631err_tcp_mib:
1632        return -ENOMEM;
1633}
1634
1635static __net_exit void ipv4_mib_exit_net(struct net *net)
1636{
1637        kfree(net->mib.icmpmsg_statistics);
1638        snmp_mib_free((void __percpu **)net->mib.icmp_statistics);
1639        snmp_mib_free((void __percpu **)net->mib.udplite_statistics);
1640        snmp_mib_free((void __percpu **)net->mib.udp_statistics);
1641        snmp_mib_free((void __percpu **)net->mib.net_statistics);
1642        snmp_mib_free((void __percpu **)net->mib.ip_statistics);
1643        snmp_mib_free((void __percpu **)net->mib.tcp_statistics);
1644}
1645
1646static __net_initdata struct pernet_operations ipv4_mib_ops = {
1647        .init = ipv4_mib_init_net,
1648        .exit = ipv4_mib_exit_net,
1649};
1650
1651static int __init init_ipv4_mibs(void)
1652{
1653        return register_pernet_subsys(&ipv4_mib_ops);
1654}
1655
1656static int ipv4_proc_init(void);
1657
1658/*
1659 *      IP protocol layer initialiser
1660 */
1661
1662static struct packet_type ip_packet_type __read_mostly = {
1663        .type = cpu_to_be16(ETH_P_IP),
1664        .func = ip_rcv,
1665        .gso_send_check = inet_gso_send_check,
1666        .gso_segment = inet_gso_segment,
1667        .gro_receive = inet_gro_receive,
1668        .gro_complete = inet_gro_complete,
1669};
1670
1671static int __init inet_init(void)
1672{
1673        struct sk_buff *dummy_skb;
1674        struct inet_protosw *q;
1675        struct list_head *r;
1676        int rc = -EINVAL;
1677
1678        BUILD_BUG_ON(sizeof(struct inet_skb_parm) > sizeof(dummy_skb->cb));
1679
1680        sysctl_local_reserved_ports = kzalloc(65536 / 8, GFP_KERNEL);
1681        if (!sysctl_local_reserved_ports)
1682                goto out;
1683
1684        rc = proto_register(&tcp_prot, 1);
1685        if (rc)
1686                goto out_free_reserved_ports;
1687
1688        rc = proto_register(&udp_prot, 1);
1689        if (rc)
1690                goto out_unregister_tcp_proto;
1691
1692        rc = proto_register(&raw_prot, 1);
1693        if (rc)
1694                goto out_unregister_udp_proto;
1695
1696        rc = proto_register(&ping_prot, 1);
1697        if (rc)
1698                goto out_unregister_raw_proto;
1699
1700        /*
1701         *      Tell SOCKET that we are alive...
1702         */
1703
1704        (void)sock_register(&inet_family_ops);
1705
1706#ifdef CONFIG_SYSCTL
1707        ip_static_sysctl_init();
1708#endif
1709
1710        tcp_prot.sysctl_mem = init_net.ipv4.sysctl_tcp_mem;
1711
1712        /*
1713         *      Add all the base protocols.
1714         */
1715
1716        if (inet_add_protocol(&icmp_protocol, IPPROTO_ICMP) < 0)
1717                pr_crit("%s: Cannot add ICMP protocol\n", __func__);
1718        if (inet_add_protocol(&udp_protocol, IPPROTO_UDP) < 0)
1719                pr_crit("%s: Cannot add UDP protocol\n", __func__);
1720        if (inet_add_protocol(&tcp_protocol, IPPROTO_TCP) < 0)
1721                pr_crit("%s: Cannot add TCP protocol\n", __func__);
1722#ifdef CONFIG_IP_MULTICAST
1723        if (inet_add_protocol(&igmp_protocol, IPPROTO_IGMP) < 0)
1724                pr_crit("%s: Cannot add IGMP protocol\n", __func__);
1725#endif
1726
1727        /* Register the socket-side information for inet_create. */
1728        for (r = &inetsw[0]; r < &inetsw[SOCK_MAX]; ++r)
1729                INIT_LIST_HEAD(r);
1730
1731        for (q = inetsw_array; q < &inetsw_array[INETSW_ARRAY_LEN]; ++q)
1732                inet_register_protosw(q);
1733
1734        /*
1735         *      Set the ARP module up
1736         */
1737
1738        arp_init();
1739
1740        /*
1741         *      Set the IP module up
1742         */
1743
1744        ip_init();
1745
1746        tcp_v4_init();
1747
1748        /* Setup TCP slab cache for open requests. */
1749        tcp_init();
1750
1751        /* Setup UDP memory threshold */
1752        udp_init();
1753
1754        /* Add UDP-Lite (RFC 3828) */
1755        udplite4_register();
1756
1757        ping_init();
1758
1759        /*
1760         *      Set the ICMP layer up
1761         */
1762
1763        if (icmp_init() < 0)
1764                panic("Failed to create the ICMP control socket.\n");
1765
1766        /*
1767         *      Initialise the multicast router
1768         */
1769#if defined(CONFIG_IP_MROUTE)
1770        if (ip_mr_init())
1771                pr_crit("%s: Cannot init ipv4 mroute\n", __func__);
1772#endif
1773        /*
1774         *      Initialise per-cpu ipv4 mibs
1775         */
1776
1777        if (init_ipv4_mibs())
1778                pr_crit("%s: Cannot init ipv4 mibs\n", __func__);
1779
1780        ipv4_proc_init();
1781
1782        ipfrag_init();
1783
1784        dev_add_pack(&ip_packet_type);
1785
1786        rc = 0;
1787out:
1788        return rc;
1789out_unregister_raw_proto:
1790        proto_unregister(&raw_prot);
1791out_unregister_udp_proto:
1792        proto_unregister(&udp_prot);
1793out_unregister_tcp_proto:
1794        proto_unregister(&tcp_prot);
1795out_free_reserved_ports:
1796        kfree(sysctl_local_reserved_ports);
1797        goto out;
1798}
1799
1800fs_initcall(inet_init);
1801
1802/* ------------------------------------------------------------------------ */
1803
1804#ifdef CONFIG_PROC_FS
1805static int __init ipv4_proc_init(void)
1806{
1807        int rc = 0;
1808
1809        if (raw_proc_init())
1810                goto out_raw;
1811        if (tcp4_proc_init())
1812                goto out_tcp;
1813        if (udp4_proc_init())
1814                goto out_udp;
1815        if (ping_proc_init())
1816                goto out_ping;
1817        if (ip_misc_proc_init())
1818                goto out_misc;
1819out:
1820        return rc;
1821out_misc:
1822        ping_proc_exit();
1823out_ping:
1824        udp4_proc_exit();
1825out_udp:
1826        tcp4_proc_exit();
1827out_tcp:
1828        raw_proc_exit();
1829out_raw:
1830        rc = -ENOMEM;
1831        goto out;
1832}
1833
1834#else /* CONFIG_PROC_FS */
1835static int __init ipv4_proc_init(void)
1836{
1837        return 0;
1838}
1839#endif /* CONFIG_PROC_FS */
1840
1841MODULE_ALIAS_NETPROTO(PF_INET);
1842
1843
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.