net/ipv4/af_inet.c

   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, <[email protected]>
  10  *              Florian La Roche, <[email protected]>
  11  *              Alan Cox, <[email protected]>
  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/kmod.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 <linux/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/inet_common.h>
 115 #include <net/ip_tunnels.h>
 116 #include <net/xfrm.h>
 117 #include <net/net_namespace.h>
 118 #include <net/secure_seq.h>
 119 #ifdef CONFIG_IP_MROUTE
 120 #include <linux/mroute.h>
 121 #endif
 122 #include <net/l3mdev.h>
 123
 124 #include <trace/events/sock.h>
 125
 126 /* The inetsw table contains everything that inet_create needs to
 127  * build a new socket.
 128  */
 129 static struct list_head inetsw[SOCK_MAX];
 130 static DEFINE_SPINLOCK(inetsw_lock);
 131
 132 /* New destruction routine */
 133
 134 void 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(refcount_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 }
 163 EXPORT_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
 175 static 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  */
 195 int inet_listen(struct socket *sock, int backlog)
 196 {
 197         struct sock *sk = sock->sk;
 198         unsigned char old_state;
 199         int err, tcp_fastopen;
 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                 /* Enable TFO w/o requiring TCP_FASTOPEN socket option.
 216                  * Note that only TCP sockets (SOCK_STREAM) will reach here.
 217                  * Also fastopen backlog may already been set via the option
 218                  * because the socket was in TCP_LISTEN state previously but
 219                  * was shutdown() rather than close().
 220                  */
 221                 tcp_fastopen = sock_net(sk)->ipv4.sysctl_tcp_fastopen;
 222                 if ((tcp_fastopen & TFO_SERVER_WO_SOCKOPT1) &&
 223                     (tcp_fastopen & TFO_SERVER_ENABLE) &&
 224                     !inet_csk(sk)->icsk_accept_queue.fastopenq.max_qlen) {
 225                         fastopen_queue_tune(sk, backlog);
 226                         tcp_fastopen_init_key_once(sock_net(sk));
 227                 }
 228
 229                 err = inet_csk_listen_start(sk, backlog);
 230                 if (err)
 231                         goto out;
 232         }
 233         sk->sk_max_ack_backlog = backlog;
 234         err = 0;
 235
 236 out:
 237         release_sock(sk);
 238         return err;
 239 }
 240 EXPORT_SYMBOL(inet_listen);
 241
 242 /*
 243  *      Create an inet socket.
 244  */
 245
 246 static int inet_create(struct net *net, struct socket *sock, int protocol,
 247                        int kern)
 248 {
 249         struct sock *sk;
 250         struct inet_protosw *answer;
 251         struct inet_sock *inet;
 252         struct proto *answer_prot;
 253         unsigned char answer_flags;
 254         int try_loading_module = 0;
 255         int err;
 256
 257         if (protocol < 0 || protocol >= IPPROTO_MAX)
 258                 return -EINVAL;
 259
 260         sock->state = SS_UNCONNECTED;
 261
 262         /* Look for the requested type/protocol pair. */
 263 lookup_protocol:
 264         err = -ESOCKTNOSUPPORT;
 265         rcu_read_lock();
 266         list_for_each_entry_rcu(answer, &inetsw[sock->type], list) {
 267
 268                 err = 0;
 269                 /* Check the non-wild match. */
 270                 if (protocol == answer->protocol) {
 271                         if (protocol != IPPROTO_IP)
 272                                 break;
 273                 } else {
 274                         /* Check for the two wild cases. */
 275                         if (IPPROTO_IP == protocol) {
 276                                 protocol = answer->protocol;
 277                                 break;
 278                         }
 279                         if (IPPROTO_IP == answer->protocol)
 280                                 break;
 281                 }
 282                 err = -EPROTONOSUPPORT;
 283         }
 284
 285         if (unlikely(err)) {
 286                 if (try_loading_module < 2) {
 287                         rcu_read_unlock();
 288                         /*
 289                          * Be more specific, e.g. net-pf-2-proto-132-type-1
 290                          * (net-pf-PF_INET-proto-IPPROTO_SCTP-type-SOCK_STREAM)
 291                          */
 292                         if (++try_loading_module == 1)
 293                                 request_module("net-pf-%d-proto-%d-type-%d",
 294                                                PF_INET, protocol, sock->type);
 295                         /*
 296                          * Fall back to generic, e.g. net-pf-2-proto-132
 297                          * (net-pf-PF_INET-proto-IPPROTO_SCTP)
 298                          */
 299                         else
 300                                 request_module("net-pf-%d-proto-%d",
 301                                                PF_INET, protocol);
 302                         goto lookup_protocol;
 303                 } else
 304                         goto out_rcu_unlock;
 305         }
 306
 307         err = -EPERM;
 308         if (sock->type == SOCK_RAW && !kern &&
 309             !ns_capable(net->user_ns, CAP_NET_RAW))
 310                 goto out_rcu_unlock;
 311
 312         sock->ops = answer->ops;
 313         answer_prot = answer->prot;
 314         answer_flags = answer->flags;
 315         rcu_read_unlock();
 316
 317         WARN_ON(!answer_prot->slab);
 318
 319         err = -ENOBUFS;
 320         sk = sk_alloc(net, PF_INET, GFP_KERNEL, answer_prot, kern);
 321         if (!sk)
 322                 goto out;
 323
 324         err = 0;
 325         if (INET_PROTOSW_REUSE & answer_flags)
 326                 sk->sk_reuse = SK_CAN_REUSE;
 327
 328         inet = inet_sk(sk);
 329         inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
 330
 331         inet->nodefrag = 0;
 332
 333         if (SOCK_RAW == sock->type) {
 334                 inet->inet_num = protocol;
 335                 if (IPPROTO_RAW == protocol)
 336                         inet->hdrincl = 1;
 337         }
 338
 339         if (net->ipv4.sysctl_ip_no_pmtu_disc)
 340                 inet->pmtudisc = IP_PMTUDISC_DONT;
 341         else
 342                 inet->pmtudisc = IP_PMTUDISC_WANT;
 343
 344         inet->inet_id = 0;
 345
 346         sock_init_data(sock, sk);
 347
 348         sk->sk_destruct    = inet_sock_destruct;
 349         sk->sk_protocol    = protocol;
 350         sk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
 351
 352         inet->uc_ttl    = -1;
 353         inet->mc_loop   = 1;
 354         inet->mc_ttl    = 1;
 355         inet->mc_all    = 1;
 356         inet->mc_index  = 0;
 357         inet->mc_list   = NULL;
 358         inet->rcv_tos   = 0;
 359
 360         sk_refcnt_debug_inc(sk);
 361
 362         if (inet->inet_num) {
 363                 /* It assumes that any protocol which allows
 364                  * the user to assign a number at socket
 365                  * creation time automatically
 366                  * shares.
 367                  */
 368                 inet->inet_sport = htons(inet->inet_num);
 369                 /* Add to protocol hash chains. */
 370                 err = sk->sk_prot->hash(sk);
 371                 if (err) {
 372                         sk_common_release(sk);
 373                         goto out;
 374                 }
 375         }
 376
 377         if (sk->sk_prot->init) {
 378                 err = sk->sk_prot->init(sk);
 379                 if (err) {
 380                         sk_common_release(sk);
 381                         goto out;
 382                 }
 383         }
 384
 385         if (!kern) {
 386                 err = BPF_CGROUP_RUN_PROG_INET_SOCK(sk);
 387                 if (err) {
 388                         sk_common_release(sk);
 389                         goto out;
 390                 }
 391         }
 392 out:
 393         return err;
 394 out_rcu_unlock:
 395         rcu_read_unlock();
 396         goto out;
 397 }
 398
 399
 400 /*
 401  *      The peer socket should always be NULL (or else). When we call this
 402  *      function we are destroying the object and from then on nobody
 403  *      should refer to it.
 404  */
 405 int inet_release(struct socket *sock)
 406 {
 407         struct sock *sk = sock->sk;
 408
 409         if (sk) {
 410                 long timeout;
 411
 412                 /* Applications forget to leave groups before exiting */
 413                 ip_mc_drop_socket(sk);
 414
 415                 /* If linger is set, we don't return until the close
 416                  * is complete.  Otherwise we return immediately. The
 417                  * actually closing is done the same either way.
 418                  *
 419                  * If the close is due to the process exiting, we never
 420                  * linger..
 421                  */
 422                 timeout = 0;
 423                 if (sock_flag(sk, SOCK_LINGER) &&
 424                     !(current->flags & PF_EXITING))
 425                         timeout = sk->sk_lingertime;
 426                 sock->sk = NULL;
 427                 sk->sk_prot->close(sk, timeout);
 428         }
 429         return 0;
 430 }
 431 EXPORT_SYMBOL(inet_release);
 432
 433 int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 434 {
 435         struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
 436         struct sock *sk = sock->sk;
 437         struct inet_sock *inet = inet_sk(sk);
 438         struct net *net = sock_net(sk);
 439         unsigned short snum;
 440         int chk_addr_ret;
 441         u32 tb_id = RT_TABLE_LOCAL;
 442         int err;
 443
 444         /* If the socket has its own bind function then use it. (RAW) */
 445         if (sk->sk_prot->bind) {
 446                 err = sk->sk_prot->bind(sk, uaddr, addr_len);
 447                 goto out;
 448         }
 449         err = -EINVAL;
 450         if (addr_len < sizeof(struct sockaddr_in))
 451                 goto out;
 452
 453         if (addr->sin_family != AF_INET) {
 454                 /* Compatibility games : accept AF_UNSPEC (mapped to AF_INET)
 455                  * only if s_addr is INADDR_ANY.
 456                  */
 457                 err = -EAFNOSUPPORT;
 458                 if (addr->sin_family != AF_UNSPEC ||
 459                     addr->sin_addr.s_addr != htonl(INADDR_ANY))
 460                         goto out;
 461         }
 462
 463         tb_id = l3mdev_fib_table_by_index(net, sk->sk_bound_dev_if) ? : tb_id;
 464         chk_addr_ret = inet_addr_type_table(net, addr->sin_addr.s_addr, tb_id);
 465
 466         /* Not specified by any standard per-se, however it breaks too
 467          * many applications when removed.  It is unfortunate since
 468          * allowing applications to make a non-local bind solves
 469          * several problems with systems using dynamic addressing.
 470          * (ie. your servers still start up even if your ISDN link
 471          *  is temporarily down)
 472          */
 473         err = -EADDRNOTAVAIL;
 474         if (!net->ipv4.sysctl_ip_nonlocal_bind &&
 475             !(inet->freebind || inet->transparent) &&
 476             addr->sin_addr.s_addr != htonl(INADDR_ANY) &&
 477             chk_addr_ret != RTN_LOCAL &&
 478             chk_addr_ret != RTN_MULTICAST &&
 479             chk_addr_ret != RTN_BROADCAST)
 480                 goto out;
 481
 482         snum = ntohs(addr->sin_port);
 483         err = -EACCES;
 484         if (snum && snum < inet_prot_sock(net) &&
 485             !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE))
 486                 goto out;
 487
 488         /*      We keep a pair of addresses. rcv_saddr is the one
 489          *      used by hash lookups, and saddr is used for transmit.
 490          *
 491          *      In the BSD API these are the same except where it
 492          *      would be illegal to use them (multicast/broadcast) in
 493          *      which case the sending device address is used.
 494          */
 495         lock_sock(sk);
 496
 497         /* Check these errors (active socket, double bind). */
 498         err = -EINVAL;
 499         if (sk->sk_state != TCP_CLOSE || inet->inet_num)
 500                 goto out_release_sock;
 501
 502         inet->inet_rcv_saddr = inet->inet_saddr = addr->sin_addr.s_addr;
 503         if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST)
 504                 inet->inet_saddr = 0;  /* Use device */
 505
 506         /* Make sure we are allowed to bind here. */
 507         if ((snum || !inet->bind_address_no_port) &&
 508             sk->sk_prot->get_port(sk, snum)) {
 509                 inet->inet_saddr = inet->inet_rcv_saddr = 0;
 510                 err = -EADDRINUSE;
 511                 goto out_release_sock;
 512         }
 513
 514         if (inet->inet_rcv_saddr)
 515                 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
 516         if (snum)
 517                 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
 518         inet->inet_sport = htons(inet->inet_num);
 519         inet->inet_daddr = 0;
 520         inet->inet_dport = 0;
 521         sk_dst_reset(sk);
 522         err = 0;
 523 out_release_sock:
 524         release_sock(sk);
 525 out:
 526         return err;
 527 }
 528 EXPORT_SYMBOL(inet_bind);
 529
 530 int inet_dgram_connect(struct socket *sock, struct sockaddr *uaddr,
 531                        int addr_len, int flags)
 532 {
 533         struct sock *sk = sock->sk;
 534
 535         if (addr_len < sizeof(uaddr->sa_family))
 536                 return -EINVAL;
 537         if (uaddr->sa_family == AF_UNSPEC)
 538                 return sk->sk_prot->disconnect(sk, flags);
 539
 540         if (!inet_sk(sk)->inet_num && inet_autobind(sk))
 541                 return -EAGAIN;
 542         return sk->sk_prot->connect(sk, uaddr, addr_len);
 543 }
 544 EXPORT_SYMBOL(inet_dgram_connect);
 545
 546 static long inet_wait_for_connect(struct sock *sk, long timeo, int writebias)
 547 {
 548         DEFINE_WAIT_FUNC(wait, woken_wake_function);
 549
 550         add_wait_queue(sk_sleep(sk), &wait);
 551         sk->sk_write_pending += writebias;
 552
 553         /* Basic assumption: if someone sets sk->sk_err, he _must_
 554          * change state of the socket from TCP_SYN_*.
 555          * Connect() does not allow to get error notifications
 556          * without closing the socket.
 557          */
 558         while ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
 559                 release_sock(sk);
 560                 timeo = wait_woken(&wait, TASK_INTERRUPTIBLE, timeo);
 561                 lock_sock(sk);
 562                 if (signal_pending(current) || !timeo)
 563                         break;
 564         }
 565         remove_wait_queue(sk_sleep(sk), &wait);
 566         sk->sk_write_pending -= writebias;
 567         return timeo;
 568 }
 569
 570 /*
 571  *      Connect to a remote host. There is regrettably still a little
 572  *      TCP 'magic' in here.
 573  */
 574 int __inet_stream_connect(struct socket *sock, struct sockaddr *uaddr,
 575                           int addr_len, int flags, int is_sendmsg)
 576 {
 577         struct sock *sk = sock->sk;
 578         int err;
 579         long timeo;
 580
 581         /*
 582          * uaddr can be NULL and addr_len can be 0 if:
 583          * sk is a TCP fastopen active socket and
 584          * TCP_FASTOPEN_CONNECT sockopt is set and
 585          * we already have a valid cookie for this socket.
 586          * In this case, user can call write() after connect().
 587          * write() will invoke tcp_sendmsg_fastopen() which calls
 588          * __inet_stream_connect().
 589          */
 590         if (uaddr) {
 591                 if (addr_len < sizeof(uaddr->sa_family))
 592                         return -EINVAL;
 593
 594                 if (uaddr->sa_family == AF_UNSPEC) {
 595                         err = sk->sk_prot->disconnect(sk, flags);
 596                         sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
 597                         goto out;
 598                 }
 599         }
 600
 601         switch (sock->state) {
 602         default:
 603                 err = -EINVAL;
 604                 goto out;
 605         case SS_CONNECTED:
 606                 err = -EISCONN;
 607                 goto out;
 608         case SS_CONNECTING:
 609                 if (inet_sk(sk)->defer_connect)
 610                         err = is_sendmsg ? -EINPROGRESS : -EISCONN;
 611                 else
 612                         err = -EALREADY;
 613                 /* Fall out of switch with err, set for this state */
 614                 break;
 615         case SS_UNCONNECTED:
 616                 err = -EISCONN;
 617                 if (sk->sk_state != TCP_CLOSE)
 618                         goto out;
 619
 620                 err = sk->sk_prot->connect(sk, uaddr, addr_len);
 621                 if (err < 0)
 622                         goto out;
 623
 624                 sock->state = SS_CONNECTING;
 625
 626                 if (!err && inet_sk(sk)->defer_connect)
 627                         goto out;
 628
 629                 /* Just entered SS_CONNECTING state; the only
 630                  * difference is that return value in non-blocking
 631                  * case is EINPROGRESS, rather than EALREADY.
 632                  */
 633                 err = -EINPROGRESS;
 634                 break;
 635         }
 636
 637         timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
 638
 639         if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
 640                 int writebias = (sk->sk_protocol == IPPROTO_TCP) &&
 641                                 tcp_sk(sk)->fastopen_req &&
 642                                 tcp_sk(sk)->fastopen_req->data ? 1 : 0;
 643
 644                 /* Error code is set above */
 645                 if (!timeo || !inet_wait_for_connect(sk, timeo, writebias))
 646                         goto out;
 647
 648                 err = sock_intr_errno(timeo);
 649                 if (signal_pending(current))
 650                         goto out;
 651         }
 652
 653         /* Connection was closed by RST, timeout, ICMP error
 654          * or another process disconnected us.
 655          */
 656         if (sk->sk_state == TCP_CLOSE)
 657                 goto sock_error;
 658
 659         /* sk->sk_err may be not zero now, if RECVERR was ordered by user
 660          * and error was received after socket entered established state.
 661          * Hence, it is handled normally after connect() return successfully.
 662          */
 663
 664         sock->state = SS_CONNECTED;
 665         err = 0;
 666 out:
 667         return err;
 668
 669 sock_error:
 670         err = sock_error(sk) ? : -ECONNABORTED;
 671         sock->state = SS_UNCONNECTED;
 672         if (sk->sk_prot->disconnect(sk, flags))
 673                 sock->state = SS_DISCONNECTING;
 674         goto out;
 675 }
 676 EXPORT_SYMBOL(__inet_stream_connect);
 677
 678 int inet_stream_connect(struct socket *sock, struct sockaddr *uaddr,
 679                         int addr_len, int flags)
 680 {
 681         int err;
 682
 683         lock_sock(sock->sk);
 684         err = __inet_stream_connect(sock, uaddr, addr_len, flags, 0);
 685         release_sock(sock->sk);
 686         return err;
 687 }
 688 EXPORT_SYMBOL(inet_stream_connect);
 689
 690 /*
 691  *      Accept a pending connection. The TCP layer now gives BSD semantics.
 692  */
 693
 694 int inet_accept(struct socket *sock, struct socket *newsock, int flags,
 695                 bool kern)
 696 {
 697         struct sock *sk1 = sock->sk;
 698         int err = -EINVAL;
 699         struct sock *sk2 = sk1->sk_prot->accept(sk1, flags, &err, kern);
 700
 701         if (!sk2)
 702                 goto do_err;
 703
 704         lock_sock(sk2);
 705
 706         sock_rps_record_flow(sk2);
 707         WARN_ON(!((1 << sk2->sk_state) &
 708                   (TCPF_ESTABLISHED | TCPF_SYN_RECV |
 709                   TCPF_CLOSE_WAIT | TCPF_CLOSE)));
 710
 711         sock_graft(sk2, newsock);
 712
 713         newsock->state = SS_CONNECTED;
 714         err = 0;
 715         release_sock(sk2);
 716 do_err:
 717         return err;
 718 }
 719 EXPORT_SYMBOL(inet_accept);
 720
 721
 722 /*
 723  *      This does both peername and sockname.
 724  */
 725 int inet_getname(struct socket *sock, struct sockaddr *uaddr,
 726                         int *uaddr_len, int peer)
 727 {
 728         struct sock *sk         = sock->sk;
 729         struct inet_sock *inet  = inet_sk(sk);
 730         DECLARE_SOCKADDR(struct sockaddr_in *, sin, uaddr);
 731
 732         sin->sin_family = AF_INET;
 733         if (peer) {
 734                 if (!inet->inet_dport ||
 735                     (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
 736                      peer == 1))
 737                         return -ENOTCONN;
 738                 sin->sin_port = inet->inet_dport;
 739                 sin->sin_addr.s_addr = inet->inet_daddr;
 740         } else {
 741                 __be32 addr = inet->inet_rcv_saddr;
 742                 if (!addr)
 743                         addr = inet->inet_saddr;
 744                 sin->sin_port = inet->inet_sport;
 745                 sin->sin_addr.s_addr = addr;
 746         }
 747         memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
 748         *uaddr_len = sizeof(*sin);
 749         return 0;
 750 }
 751 EXPORT_SYMBOL(inet_getname);
 752
 753 int inet_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
 754 {
 755         struct sock *sk = sock->sk;
 756
 757         sock_rps_record_flow(sk);
 758
 759         /* We may need to bind the socket. */
 760         if (!inet_sk(sk)->inet_num && !sk->sk_prot->no_autobind &&
 761             inet_autobind(sk))
 762                 return -EAGAIN;
 763
 764         return sk->sk_prot->sendmsg(sk, msg, size);
 765 }
 766 EXPORT_SYMBOL(inet_sendmsg);
 767
 768 ssize_t inet_sendpage(struct socket *sock, struct page *page, int offset,
 769                       size_t size, int flags)
 770 {
 771         struct sock *sk = sock->sk;
 772
 773         sock_rps_record_flow(sk);
 774
 775         /* We may need to bind the socket. */
 776         if (!inet_sk(sk)->inet_num && !sk->sk_prot->no_autobind &&
 777             inet_autobind(sk))
 778                 return -EAGAIN;
 779
 780         if (sk->sk_prot->sendpage)
 781                 return sk->sk_prot->sendpage(sk, page, offset, size, flags);
 782         return sock_no_sendpage(sock, page, offset, size, flags);
 783 }
 784 EXPORT_SYMBOL(inet_sendpage);
 785
 786 int inet_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
 787                  int flags)
 788 {
 789         struct sock *sk = sock->sk;
 790         int addr_len = 0;
 791         int err;
 792
 793         if (likely(!(flags & MSG_ERRQUEUE)))
 794                 sock_rps_record_flow(sk);
 795
 796         err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
 797                                    flags & ~MSG_DONTWAIT, &addr_len);
 798         if (err >= 0)
 799                 msg->msg_namelen = addr_len;
 800         return err;
 801 }
 802 EXPORT_SYMBOL(inet_recvmsg);
 803
 804 int inet_shutdown(struct socket *sock, int how)
 805 {
 806         struct sock *sk = sock->sk;
 807         int err = 0;
 808
 809         /* This should really check to make sure
 810          * the socket is a TCP socket. (WHY AC...)
 811          */
 812         how++; /* maps 0->1 has the advantage of making bit 1 rcvs and
 813                        1->2 bit 2 snds.
 814                        2->3 */
 815         if ((how & ~SHUTDOWN_MASK) || !how)     /* MAXINT->0 */
 816                 return -EINVAL;
 817
 818         lock_sock(sk);
 819         if (sock->state == SS_CONNECTING) {
 820                 if ((1 << sk->sk_state) &
 821                     (TCPF_SYN_SENT | TCPF_SYN_RECV | TCPF_CLOSE))
 822                         sock->state = SS_DISCONNECTING;
 823                 else
 824                         sock->state = SS_CONNECTED;
 825         }
 826
 827         switch (sk->sk_state) {
 828         case TCP_CLOSE:
 829                 err = -ENOTCONN;
 830                 /* Hack to wake up other listeners, who can poll for
 831                    POLLHUP, even on eg. unconnected UDP sockets -- RR */
 832                 /* fall through */
 833         default:
 834                 sk->sk_shutdown |= how;
 835                 if (sk->sk_prot->shutdown)
 836                         sk->sk_prot->shutdown(sk, how);
 837                 break;
 838
 839         /* Remaining two branches are temporary solution for missing
 840          * close() in multithreaded environment. It is _not_ a good idea,
 841          * but we have no choice until close() is repaired at VFS level.
 842          */
 843         case TCP_LISTEN:
 844                 if (!(how & RCV_SHUTDOWN))
 845                         break;
 846                 /* fall through */
 847         case TCP_SYN_SENT:
 848                 err = sk->sk_prot->disconnect(sk, O_NONBLOCK);
 849                 sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
 850                 break;
 851         }
 852
 853         /* Wake up anyone sleeping in poll. */
 854         sk->sk_state_change(sk);
 855         release_sock(sk);
 856         return err;
 857 }
 858 EXPORT_SYMBOL(inet_shutdown);
 859
 860 /*
 861  *      ioctl() calls you can issue on an INET socket. Most of these are
 862  *      device configuration and stuff and very rarely used. Some ioctls
 863  *      pass on to the socket itself.
 864  *
 865  *      NOTE: I like the idea of a module for the config stuff. ie ifconfig
 866  *      loads the devconfigure module does its configuring and unloads it.
 867  *      There's a good 20K of config code hanging around the kernel.
 868  */
 869
 870 int inet_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 871 {
 872         struct sock *sk = sock->sk;
 873         int err = 0;
 874         struct net *net = sock_net(sk);
 875         void __user *p = (void __user *)arg;
 876         struct ifreq ifr;
 877         struct rtentry rt;
 878
 879         switch (cmd) {
 880         case SIOCGSTAMP:
 881                 err = sock_get_timestamp(sk, (struct timeval __user *)arg);
 882                 break;
 883         case SIOCGSTAMPNS:
 884                 err = sock_get_timestampns(sk, (struct timespec __user *)arg);
 885                 break;
 886         case SIOCADDRT:
 887         case SIOCDELRT:
 888                 if (copy_from_user(&rt, p, sizeof(struct rtentry)))
 889                         return -EFAULT;
 890                 err = ip_rt_ioctl(net, cmd, &rt);
 891                 break;
 892         case SIOCRTMSG:
 893                 err = -EINVAL;
 894                 break;
 895         case SIOCDARP:
 896         case SIOCGARP:
 897         case SIOCSARP:
 898                 err = arp_ioctl(net, cmd, (void __user *)arg);
 899                 break;
 900         case SIOCGIFADDR:
 901         case SIOCGIFBRDADDR:
 902         case SIOCGIFNETMASK:
 903         case SIOCGIFDSTADDR:
 904         case SIOCGIFPFLAGS:
 905                 if (copy_from_user(&ifr, p, sizeof(struct ifreq)))
 906                         return -EFAULT;
 907                 err = devinet_ioctl(net, cmd, &ifr);
 908                 if (!err && copy_to_user(p, &ifr, sizeof(struct ifreq)))
 909                         err = -EFAULT;
 910                 break;
 911
 912         case SIOCSIFADDR:
 913         case SIOCSIFBRDADDR:
 914         case SIOCSIFNETMASK:
 915         case SIOCSIFDSTADDR:
 916         case SIOCSIFPFLAGS:
 917         case SIOCSIFFLAGS:
 918                 if (copy_from_user(&ifr, p, sizeof(struct ifreq)))
 919                         return -EFAULT;
 920                 err = devinet_ioctl(net, cmd, &ifr);
 921                 break;
 922         default:
 923                 if (sk->sk_prot->ioctl)
 924                         err = sk->sk_prot->ioctl(sk, cmd, arg);
 925                 else
 926                         err = -ENOIOCTLCMD;
 927                 break;
 928         }
 929         return err;
 930 }
 931 EXPORT_SYMBOL(inet_ioctl);
 932
 933 #ifdef CONFIG_COMPAT
 934 static int inet_compat_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 935 {
 936         struct sock *sk = sock->sk;
 937         int err = -ENOIOCTLCMD;
 938
 939         if (sk->sk_prot->compat_ioctl)
 940                 err = sk->sk_prot->compat_ioctl(sk, cmd, arg);
 941
 942         return err;
 943 }
 944 #endif
 945
 946 const struct proto_ops inet_stream_ops = {
 947         .family            = PF_INET,
 948         .owner             = THIS_MODULE,
 949         .release           = inet_release,
 950         .bind              = inet_bind,
 951         .connect           = inet_stream_connect,
 952         .socketpair        = sock_no_socketpair,
 953         .accept            = inet_accept,
 954         .getname           = inet_getname,
 955         .poll              = tcp_poll,
 956         .ioctl             = inet_ioctl,
 957         .listen            = inet_listen,
 958         .shutdown          = inet_shutdown,
 959         .setsockopt        = sock_common_setsockopt,
 960         .getsockopt        = sock_common_getsockopt,
 961         .sendmsg           = inet_sendmsg,
 962         .recvmsg           = inet_recvmsg,
 963         .mmap              = sock_no_mmap,
 964         .sendpage          = inet_sendpage,
 965         .splice_read       = tcp_splice_read,
 966         .read_sock         = tcp_read_sock,
 967         .sendmsg_locked    = tcp_sendmsg_locked,
 968         .sendpage_locked   = tcp_sendpage_locked,
 969         .peek_len          = tcp_peek_len,
 970 #ifdef CONFIG_COMPAT
 971         .compat_setsockopt = compat_sock_common_setsockopt,
 972         .compat_getsockopt = compat_sock_common_getsockopt,
 973         .compat_ioctl      = inet_compat_ioctl,
 974 #endif
 975 };
 976 EXPORT_SYMBOL(inet_stream_ops);
 977
 978 const struct proto_ops inet_dgram_ops = {
 979         .family            = PF_INET,
 980         .owner             = THIS_MODULE,
 981         .release           = inet_release,
 982         .bind              = inet_bind,
 983         .connect           = inet_dgram_connect,
 984         .socketpair        = sock_no_socketpair,
 985         .accept            = sock_no_accept,
 986         .getname           = inet_getname,
 987         .poll              = udp_poll,
 988         .ioctl             = inet_ioctl,
 989         .listen            = sock_no_listen,
 990         .shutdown          = inet_shutdown,
 991         .setsockopt        = sock_common_setsockopt,
 992         .getsockopt        = sock_common_getsockopt,
 993         .sendmsg           = inet_sendmsg,
 994         .recvmsg           = inet_recvmsg,
 995         .mmap              = sock_no_mmap,
 996         .sendpage          = inet_sendpage,
 997         .set_peek_off      = sk_set_peek_off,
 998 #ifdef CONFIG_COMPAT
 999         .compat_setsockopt = compat_sock_common_setsockopt,
1000         .compat_getsockopt = compat_sock_common_getsockopt,
1001         .compat_ioctl      = inet_compat_ioctl,
1002 #endif
1003 };
1004 EXPORT_SYMBOL(inet_dgram_ops);
1005
1006 /*
1007  * For SOCK_RAW sockets; should be the same as inet_dgram_ops but without
1008  * udp_poll
1009  */
1010 static const struct proto_ops inet_sockraw_ops = {
1011         .family            = PF_INET,
1012         .owner             = THIS_MODULE,
1013         .release           = inet_release,
1014         .bind              = inet_bind,
1015         .connect           = inet_dgram_connect,
1016         .socketpair        = sock_no_socketpair,
1017         .accept            = sock_no_accept,
1018         .getname           = inet_getname,
1019         .poll              = datagram_poll,
1020         .ioctl             = inet_ioctl,
1021         .listen            = sock_no_listen,
1022         .shutdown          = inet_shutdown,
1023         .setsockopt        = sock_common_setsockopt,
1024         .getsockopt        = sock_common_getsockopt,
1025         .sendmsg           = inet_sendmsg,
1026         .recvmsg           = inet_recvmsg,
1027         .mmap              = sock_no_mmap,
1028         .sendpage          = inet_sendpage,
1029 #ifdef CONFIG_COMPAT
1030         .compat_setsockopt = compat_sock_common_setsockopt,
1031         .compat_getsockopt = compat_sock_common_getsockopt,
1032         .compat_ioctl      = inet_compat_ioctl,
1033 #endif
1034 };
1035
1036 static const struct net_proto_family inet_family_ops = {
1037         .family = PF_INET,
1038         .create = inet_create,
1039         .owner  = THIS_MODULE,
1040 };
1041
1042 /* Upon startup we insert all the elements in inetsw_array[] into
1043  * the linked list inetsw.
1044  */
1045 static struct inet_protosw inetsw_array[] =
1046 {
1047         {
1048                 .type =       SOCK_STREAM,
1049                 .protocol =   IPPROTO_TCP,
1050                 .prot =       &tcp_prot,
1051                 .ops =        &inet_stream_ops,
1052                 .flags =      INET_PROTOSW_PERMANENT |
1053                               INET_PROTOSW_ICSK,
1054         },
1055
1056         {
1057                 .type =       SOCK_DGRAM,
1058                 .protocol =   IPPROTO_UDP,
1059                 .prot =       &udp_prot,
1060                 .ops =        &inet_dgram_ops,
1061                 .flags =      INET_PROTOSW_PERMANENT,
1062        },
1063
1064        {
1065                 .type =       SOCK_DGRAM,
1066                 .protocol =   IPPROTO_ICMP,
1067                 .prot =       &ping_prot,
1068                 .ops =        &inet_sockraw_ops,
1069                 .flags =      INET_PROTOSW_REUSE,
1070        },
1071
1072        {
1073                .type =       SOCK_RAW,
1074                .protocol =   IPPROTO_IP,        /* wild card */
1075                .prot =       &raw_prot,
1076                .ops =        &inet_sockraw_ops,
1077                .flags =      INET_PROTOSW_REUSE,
1078        }
1079 };
1080
1081 #define INETSW_ARRAY_LEN ARRAY_SIZE(inetsw_array)
1082
1083 void inet_register_protosw(struct inet_protosw *p)
1084 {
1085         struct list_head *lh;
1086         struct inet_protosw *answer;
1087         int protocol = p->protocol;
1088         struct list_head *last_perm;
1089
1090         spin_lock_bh(&inetsw_lock);
1091
1092         if (p->type >= SOCK_MAX)
1093                 goto out_illegal;
1094
1095         /* If we are trying to override a permanent protocol, bail. */
1096         last_perm = &inetsw[p->type];
1097         list_for_each(lh, &inetsw[p->type]) {
1098                 answer = list_entry(lh, struct inet_protosw, list);
1099                 /* Check only the non-wild match. */
1100                 if ((INET_PROTOSW_PERMANENT & answer->flags) == 0)
1101                         break;
1102                 if (protocol == answer->protocol)
1103                         goto out_permanent;
1104                 last_perm = lh;
1105         }
1106
1107         /* Add the new entry after the last permanent entry if any, so that
1108          * the new entry does not override a permanent entry when matched with
1109          * a wild-card protocol. But it is allowed to override any existing
1110          * non-permanent entry.  This means that when we remove this entry, the
1111          * system automatically returns to the old behavior.
1112          */
1113         list_add_rcu(&p->list, last_perm);
1114 out:
1115         spin_unlock_bh(&inetsw_lock);
1116
1117         return;
1118
1119 out_permanent:
1120         pr_err("Attempt to override permanent protocol %d\n", protocol);
1121         goto out;
1122
1123 out_illegal:
1124         pr_err("Ignoring attempt to register invalid socket type %d\n",
1125                p->type);
1126         goto out;
1127 }
1128 EXPORT_SYMBOL(inet_register_protosw);
1129
1130 void inet_unregister_protosw(struct inet_protosw *p)
1131 {
1132         if (INET_PROTOSW_PERMANENT & p->flags) {
1133                 pr_err("Attempt to unregister permanent protocol %d\n",
1134                        p->protocol);
1135         } else {
1136                 spin_lock_bh(&inetsw_lock);
1137                 list_del_rcu(&p->list);
1138                 spin_unlock_bh(&inetsw_lock);
1139
1140                 synchronize_net();
1141         }
1142 }
1143 EXPORT_SYMBOL(inet_unregister_protosw);
1144
1145 static int inet_sk_reselect_saddr(struct sock *sk)
1146 {
1147         struct inet_sock *inet = inet_sk(sk);
1148         __be32 old_saddr = inet->inet_saddr;
1149         __be32 daddr = inet->inet_daddr;
1150         struct flowi4 *fl4;
1151         struct rtable *rt;
1152         __be32 new_saddr;
1153         struct ip_options_rcu *inet_opt;
1154
1155         inet_opt = rcu_dereference_protected(inet->inet_opt,
1156                                              lockdep_sock_is_held(sk));
1157         if (inet_opt && inet_opt->opt.srr)
1158                 daddr = inet_opt->opt.faddr;
1159
1160         /* Query new route. */
1161         fl4 = &inet->cork.fl.u.ip4;
1162         rt = ip_route_connect(fl4, daddr, 0, RT_CONN_FLAGS(sk),
1163                               sk->sk_bound_dev_if, sk->sk_protocol,
1164                               inet->inet_sport, inet->inet_dport, sk);
1165         if (IS_ERR(rt))
1166                 return PTR_ERR(rt);
1167
1168         sk_setup_caps(sk, &rt->dst);
1169
1170         new_saddr = fl4->saddr;
1171
1172         if (new_saddr == old_saddr)
1173                 return 0;
1174
1175         if (sock_net(sk)->ipv4.sysctl_ip_dynaddr > 1) {
1176                 pr_info("%s(): shifting inet->saddr from %pI4 to %pI4\n",
1177                         __func__, &old_saddr, &new_saddr);
1178         }
1179
1180         inet->inet_saddr = inet->inet_rcv_saddr = new_saddr;
1181
1182         /*
1183          * XXX The only one ugly spot where we need to
1184          * XXX really change the sockets identity after
1185          * XXX it has entered the hashes. -DaveM
1186          *
1187          * Besides that, it does not check for connection
1188          * uniqueness. Wait for troubles.
1189          */
1190         return __sk_prot_rehash(sk);
1191 }
1192
1193 int inet_sk_rebuild_header(struct sock *sk)
1194 {
1195         struct inet_sock *inet = inet_sk(sk);
1196         struct rtable *rt = (struct rtable *)__sk_dst_check(sk, 0);
1197         __be32 daddr;
1198         struct ip_options_rcu *inet_opt;
1199         struct flowi4 *fl4;
1200         int err;
1201
1202         /* Route is OK, nothing to do. */
1203         if (rt)
1204                 return 0;
1205
1206         /* Reroute. */
1207         rcu_read_lock();
1208         inet_opt = rcu_dereference(inet->inet_opt);
1209         daddr = inet->inet_daddr;
1210         if (inet_opt && inet_opt->opt.srr)
1211                 daddr = inet_opt->opt.faddr;
1212         rcu_read_unlock();
1213         fl4 = &inet->cork.fl.u.ip4;
1214         rt = ip_route_output_ports(sock_net(sk), fl4, sk, daddr, inet->inet_saddr,
1215                                    inet->inet_dport, inet->inet_sport,
1216                                    sk->sk_protocol, RT_CONN_FLAGS(sk),
1217                                    sk->sk_bound_dev_if);
1218         if (!IS_ERR(rt)) {
1219                 err = 0;
1220                 sk_setup_caps(sk, &rt->dst);
1221         } else {
1222                 err = PTR_ERR(rt);
1223
1224                 /* Routing failed... */
1225                 sk->sk_route_caps = 0;
1226                 /*
1227                  * Other protocols have to map its equivalent state to TCP_SYN_SENT.
1228                  * DCCP maps its DCCP_REQUESTING state to TCP_SYN_SENT. -acme
1229                  */
1230                 if (!sock_net(sk)->ipv4.sysctl_ip_dynaddr ||
1231                     sk->sk_state != TCP_SYN_SENT ||
1232                     (sk->sk_userlocks & SOCK_BINDADDR_LOCK) ||
1233                     (err = inet_sk_reselect_saddr(sk)) != 0)
1234                         sk->sk_err_soft = -err;
1235         }
1236
1237         return err;
1238 }
1239 EXPORT_SYMBOL(inet_sk_rebuild_header);
1240
1241 void inet_sk_set_state(struct sock *sk, int state)
1242 {
1243         trace_inet_sock_set_state(sk, sk->sk_state, state);
1244         sk->sk_state = state;
1245 }
1246 EXPORT_SYMBOL(inet_sk_set_state);
1247
1248 void inet_sk_state_store(struct sock *sk, int newstate)
1249 {
1250         trace_inet_sock_set_state(sk, sk->sk_state, newstate);
1251         smp_store_release(&sk->sk_state, newstate);
1252 }
1253
1254 struct sk_buff *inet_gso_segment(struct sk_buff *skb,
1255                                  netdev_features_t features)
1256 {
1257         bool udpfrag = false, fixedid = false, gso_partial, encap;
1258         struct sk_buff *segs = ERR_PTR(-EINVAL);
1259         const struct net_offload *ops;
1260         unsigned int offset = 0;
1261         struct iphdr *iph;
1262         int proto, tot_len;
1263         int nhoff;
1264         int ihl;
1265         int id;
1266
1267         skb_reset_network_header(skb);
1268         nhoff = skb_network_header(skb) - skb_mac_header(skb);
1269         if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
1270                 goto out;
1271
1272         iph = ip_hdr(skb);
1273         ihl = iph->ihl * 4;
1274         if (ihl < sizeof(*iph))
1275                 goto out;
1276
1277         id = ntohs(iph->id);
1278         proto = iph->protocol;
1279
1280         /* Warning: after this point, iph might be no longer valid */
1281         if (unlikely(!pskb_may_pull(skb, ihl)))
1282                 goto out;
1283         __skb_pull(skb, ihl);
1284
1285         encap = SKB_GSO_CB(skb)->encap_level > 0;
1286         if (encap)
1287                 features &= skb->dev->hw_enc_features;
1288         SKB_GSO_CB(skb)->encap_level += ihl;
1289
1290         skb_reset_transport_header(skb);
1291
1292         segs = ERR_PTR(-EPROTONOSUPPORT);
1293
1294         if (!skb->encapsulation || encap) {
1295                 udpfrag = !!(skb_shinfo(skb)->gso_type & SKB_GSO_UDP);
1296                 fixedid = !!(skb_shinfo(skb)->gso_type & SKB_GSO_TCP_FIXEDID);
1297
1298                 /* fixed ID is invalid if DF bit is not set */
1299                 if (fixedid && !(ip_hdr(skb)->frag_off & htons(IP_DF)))
1300                         goto out;
1301         }
1302
1303         ops = rcu_dereference(inet_offloads[proto]);
1304         if (likely(ops && ops->callbacks.gso_segment))
1305                 segs = ops->callbacks.gso_segment(skb, features);
1306
1307         if (IS_ERR_OR_NULL(segs))
1308                 goto out;
1309
1310         gso_partial = !!(skb_shinfo(segs)->gso_type & SKB_GSO_PARTIAL);
1311
1312         skb = segs;
1313         do {
1314                 iph = (struct iphdr *)(skb_mac_header(skb) + nhoff);
1315                 if (udpfrag) {
1316                         iph->frag_off = htons(offset >> 3);
1317                         if (skb->next)
1318                                 iph->frag_off |= htons(IP_MF);
1319                         offset += skb->len - nhoff - ihl;
1320                         tot_len = skb->len - nhoff;
1321                 } else if (skb_is_gso(skb)) {
1322                         if (!fixedid) {
1323                                 iph->id = htons(id);
1324                                 id += skb_shinfo(skb)->gso_segs;
1325                         }
1326
1327                         if (gso_partial)
1328                                 tot_len = skb_shinfo(skb)->gso_size +
1329                                           SKB_GSO_CB(skb)->data_offset +
1330                                           skb->head - (unsigned char *)iph;
1331                         else
1332                                 tot_len = skb->len - nhoff;
1333                 } else {
1334                         if (!fixedid)
1335                                 iph->id = htons(id++);
1336                         tot_len = skb->len - nhoff;
1337                 }
1338                 iph->tot_len = htons(tot_len);
1339                 ip_send_check(iph);
1340                 if (encap)
1341                         skb_reset_inner_headers(skb);
1342                 skb->network_header = (u8 *)iph - skb->head;
1343         } while ((skb = skb->next));
1344
1345 out:
1346         return segs;
1347 }
1348 EXPORT_SYMBOL(inet_gso_segment);
1349
1350 struct sk_buff **inet_gro_receive(struct sk_buff **head, struct sk_buff *skb)
1351 {
1352         const struct net_offload *ops;
1353         struct sk_buff **pp = NULL;
1354         struct sk_buff *p;
1355         const struct iphdr *iph;
1356         unsigned int hlen;
1357         unsigned int off;
1358         unsigned int id;
1359         int flush = 1;
1360         int proto;
1361
1362         off = skb_gro_offset(skb);
1363         hlen = off + sizeof(*iph);
1364         iph = skb_gro_header_fast(skb, off);
1365         if (skb_gro_header_hard(skb, hlen)) {
1366                 iph = skb_gro_header_slow(skb, hlen, off);
1367                 if (unlikely(!iph))
1368                         goto out;
1369         }
1370
1371         proto = iph->protocol;
1372
1373         rcu_read_lock();
1374         ops = rcu_dereference(inet_offloads[proto]);
1375         if (!ops || !ops->callbacks.gro_receive)
1376                 goto out_unlock;
1377
1378         if (*(u8 *)iph != 0x45)
1379                 goto out_unlock;
1380
1381         if (ip_is_fragment(iph))
1382                 goto out_unlock;
1383
1384         if (unlikely(ip_fast_csum((u8 *)iph, 5)))
1385                 goto out_unlock;
1386
1387         id = ntohl(*(__be32 *)&iph->id);
1388         flush = (u16)((ntohl(*(__be32 *)iph) ^ skb_gro_len(skb)) | (id & ~IP_DF));
1389         id >>= 16;
1390
1391         for (p = *head; p; p = p->next) {
1392                 struct iphdr *iph2;
1393                 u16 flush_id;
1394
1395                 if (!NAPI_GRO_CB(p)->same_flow)
1396                         continue;
1397
1398                 iph2 = (struct iphdr *)(p->data + off);
1399                 /* The above works because, with the exception of the top
1400                  * (inner most) layer, we only aggregate pkts with the same
1401                  * hdr length so all the hdrs we'll need to verify will start
1402                  * at the same offset.
1403                  */
1404                 if ((iph->protocol ^ iph2->protocol) |
1405                     ((__force u32)iph->saddr ^ (__force u32)iph2->saddr) |
1406                     ((__force u32)iph->daddr ^ (__force u32)iph2->daddr)) {
1407                         NAPI_GRO_CB(p)->same_flow = 0;
1408                         continue;
1409                 }
1410
1411                 /* All fields must match except length and checksum. */
1412                 NAPI_GRO_CB(p)->flush |=
1413                         (iph->ttl ^ iph2->ttl) |
1414                         (iph->tos ^ iph2->tos) |
1415                         ((iph->frag_off ^ iph2->frag_off) & htons(IP_DF));
1416
1417                 NAPI_GRO_CB(p)->flush |= flush;
1418
1419                 /* We need to store of the IP ID check to be included later
1420                  * when we can verify that this packet does in fact belong
1421                  * to a given flow.
1422                  */
1423                 flush_id = (u16)(id - ntohs(iph2->id));
1424
1425                 /* This bit of code makes it much easier for us to identify
1426                  * the cases where we are doing atomic vs non-atomic IP ID
1427                  * checks.  Specifically an atomic check can return IP ID
1428                  * values 0 - 0xFFFF, while a non-atomic check can only
1429                  * return 0 or 0xFFFF.
1430                  */
1431                 if (!NAPI_GRO_CB(p)->is_atomic ||
1432                     !(iph->frag_off & htons(IP_DF))) {
1433                         flush_id ^= NAPI_GRO_CB(p)->count;
1434                         flush_id = flush_id ? 0xFFFF : 0;
1435                 }
1436
1437                 /* If the previous IP ID value was based on an atomic
1438                  * datagram we can overwrite the value and ignore it.
1439                  */
1440                 if (NAPI_GRO_CB(skb)->is_atomic)
1441                         NAPI_GRO_CB(p)->flush_id = flush_id;
1442                 else
1443                         NAPI_GRO_CB(p)->flush_id |= flush_id;
1444         }
1445
1446         NAPI_GRO_CB(skb)->is_atomic = !!(iph->frag_off & htons(IP_DF));
1447         NAPI_GRO_CB(skb)->flush |= flush;
1448         skb_set_network_header(skb, off);
1449         /* The above will be needed by the transport layer if there is one
1450          * immediately following this IP hdr.
1451          */
1452
1453         /* Note : No need to call skb_gro_postpull_rcsum() here,
1454          * as we already checked checksum over ipv4 header was 0
1455          */
1456         skb_gro_pull(skb, sizeof(*iph));
1457         skb_set_transport_header(skb, skb_gro_offset(skb));
1458
1459         pp = call_gro_receive(ops->callbacks.gro_receive, head, skb);
1460
1461 out_unlock:
1462         rcu_read_unlock();
1463
1464 out:
1465         skb_gro_flush_final(skb, pp, flush);
1466
1467         return pp;
1468 }
1469 EXPORT_SYMBOL(inet_gro_receive);
1470
1471 static struct sk_buff **ipip_gro_receive(struct sk_buff **head,
1472                                          struct sk_buff *skb)
1473 {
1474         if (NAPI_GRO_CB(skb)->encap_mark) {
1475                 NAPI_GRO_CB(skb)->flush = 1;
1476                 return NULL;
1477         }
1478
1479         NAPI_GRO_CB(skb)->encap_mark = 1;
1480
1481         return inet_gro_receive(head, skb);
1482 }
1483
1484 #define SECONDS_PER_DAY 86400
1485
1486 /* inet_current_timestamp - Return IP network timestamp
1487  *
1488  * Return milliseconds since midnight in network byte order.
1489  */
1490 __be32 inet_current_timestamp(void)
1491 {
1492         u32 secs;
1493         u32 msecs;
1494         struct timespec64 ts;
1495
1496         ktime_get_real_ts64(&ts);
1497
1498         /* Get secs since midnight. */
1499         (void)div_u64_rem(ts.tv_sec, SECONDS_PER_DAY, &secs);
1500         /* Convert to msecs. */
1501         msecs = secs * MSEC_PER_SEC;
1502         /* Convert nsec to msec. */
1503         msecs += (u32)ts.tv_nsec / NSEC_PER_MSEC;
1504
1505         /* Convert to network byte order. */
1506         return htonl(msecs);
1507 }
1508 EXPORT_SYMBOL(inet_current_timestamp);
1509
1510 int inet_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
1511 {
1512         if (sk->sk_family == AF_INET)
1513                 return ip_recv_error(sk, msg, len, addr_len);
1514 #if IS_ENABLED(CONFIG_IPV6)
1515         if (sk->sk_family == AF_INET6)
1516                 return pingv6_ops.ipv6_recv_error(sk, msg, len, addr_len);
1517 #endif
1518         return -EINVAL;
1519 }
1520
1521 int inet_gro_complete(struct sk_buff *skb, int nhoff)
1522 {
1523         __be16 newlen = htons(skb->len - nhoff);
1524         struct iphdr *iph = (struct iphdr *)(skb->data + nhoff);
1525         const struct net_offload *ops;
1526         int proto = iph->protocol;
1527         int err = -ENOSYS;
1528
1529         if (skb->encapsulation) {
1530                 skb_set_inner_protocol(skb, cpu_to_be16(ETH_P_IP));
1531                 skb_set_inner_network_header(skb, nhoff);
1532         }
1533
1534         csum_replace2(&iph->check, iph->tot_len, newlen);
1535         iph->tot_len = newlen;
1536
1537         rcu_read_lock();
1538         ops = rcu_dereference(inet_offloads[proto]);
1539         if (WARN_ON(!ops || !ops->callbacks.gro_complete))
1540                 goto out_unlock;
1541
1542         /* Only need to add sizeof(*iph) to get to the next hdr below
1543          * because any hdr with option will have been flushed in
1544          * inet_gro_receive().
1545          */
1546         err = ops->callbacks.gro_complete(skb, nhoff + sizeof(*iph));
1547
1548 out_unlock:
1549         rcu_read_unlock();
1550
1551         return err;
1552 }
1553 EXPORT_SYMBOL(inet_gro_complete);
1554
1555 static int ipip_gro_complete(struct sk_buff *skb, int nhoff)
1556 {
1557         skb->encapsulation = 1;
1558         skb_shinfo(skb)->gso_type |= SKB_GSO_IPXIP4;
1559         return inet_gro_complete(skb, nhoff);
1560 }
1561
1562 int inet_ctl_sock_create(struct sock **sk, unsigned short family,
1563                          unsigned short type, unsigned char protocol,
1564                          struct net *net)
1565 {
1566         struct socket *sock;
1567         int rc = sock_create_kern(net, family, type, protocol, &sock);
1568
1569         if (rc == 0) {
1570                 *sk = sock->sk;
1571                 (*sk)->sk_allocation = GFP_ATOMIC;
1572                 /*
1573                  * Unhash it so that IP input processing does not even see it,
1574                  * we do not wish this socket to see incoming packets.
1575                  */
1576                 (*sk)->sk_prot->unhash(*sk);
1577         }
1578         return rc;
1579 }
1580 EXPORT_SYMBOL_GPL(inet_ctl_sock_create);
1581
1582 u64 snmp_get_cpu_field(void __percpu *mib, int cpu, int offt)
1583 {
1584         return  *(((unsigned long *)per_cpu_ptr(mib, cpu)) + offt);
1585 }
1586 EXPORT_SYMBOL_GPL(snmp_get_cpu_field);
1587
1588 unsigned long snmp_fold_field(void __percpu *mib, int offt)
1589 {
1590         unsigned long res = 0;
1591         int i;
1592
1593         for_each_possible_cpu(i)
1594                 res += snmp_get_cpu_field(mib, i, offt);
1595         return res;
1596 }
1597 EXPORT_SYMBOL_GPL(snmp_fold_field);
1598
1599 #if BITS_PER_LONG==32
1600
1601 u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offt,
1602                          size_t syncp_offset)
1603 {
1604         void *bhptr;
1605         struct u64_stats_sync *syncp;
1606         u64 v;
1607         unsigned int start;
1608
1609         bhptr = per_cpu_ptr(mib, cpu);
1610         syncp = (struct u64_stats_sync *)(bhptr + syncp_offset);
1611         do {
1612                 start = u64_stats_fetch_begin_irq(syncp);
1613                 v = *(((u64 *)bhptr) + offt);
1614         } while (u64_stats_fetch_retry_irq(syncp, start));
1615
1616         return v;
1617 }
1618 EXPORT_SYMBOL_GPL(snmp_get_cpu_field64);
1619
1620 u64 snmp_fold_field64(void __percpu *mib, int offt, size_t syncp_offset)
1621 {
1622         u64 res = 0;
1623         int cpu;
1624
1625         for_each_possible_cpu(cpu) {
1626                 res += snmp_get_cpu_field64(mib, cpu, offt, syncp_offset);
1627         }
1628         return res;
1629 }
1630 EXPORT_SYMBOL_GPL(snmp_fold_field64);
1631 #endif
1632
1633 #ifdef CONFIG_IP_MULTICAST
1634 static const struct net_protocol igmp_protocol = {
1635         .handler =      igmp_rcv,
1636         .netns_ok =     1,
1637 };
1638 #endif
1639
1640 /* thinking of making this const? Don't.
1641  * early_demux can change based on sysctl.
1642  */
1643 static struct net_protocol tcp_protocol = {
1644         .early_demux    =       tcp_v4_early_demux,
1645         .early_demux_handler =  tcp_v4_early_demux,
1646         .handler        =       tcp_v4_rcv,
1647         .err_handler    =       tcp_v4_err,
1648         .no_policy      =       1,
1649         .netns_ok       =       1,
1650         .icmp_strict_tag_validation = 1,
1651 };
1652
1653 /* thinking of making this const? Don't.
1654  * early_demux can change based on sysctl.
1655  */
1656 static struct net_protocol udp_protocol = {
1657         .early_demux =  udp_v4_early_demux,
1658         .early_demux_handler =  udp_v4_early_demux,
1659         .handler =      udp_rcv,
1660         .err_handler =  udp_err,
1661         .no_policy =    1,
1662         .netns_ok =     1,
1663 };
1664
1665 static const struct net_protocol icmp_protocol = {
1666         .handler =      icmp_rcv,
1667         .err_handler =  icmp_err,
1668         .no_policy =    1,
1669         .netns_ok =     1,
1670 };
1671
1672 static __net_init int ipv4_mib_init_net(struct net *net)
1673 {
1674         int i;
1675
1676         net->mib.tcp_statistics = alloc_percpu(struct tcp_mib);
1677         if (!net->mib.tcp_statistics)
1678                 goto err_tcp_mib;
1679         net->mib.ip_statistics = alloc_percpu(struct ipstats_mib);
1680         if (!net->mib.ip_statistics)
1681                 goto err_ip_mib;
1682
1683         for_each_possible_cpu(i) {
1684                 struct ipstats_mib *af_inet_stats;
1685                 af_inet_stats = per_cpu_ptr(net->mib.ip_statistics, i);
1686                 u64_stats_init(&af_inet_stats->syncp);
1687         }
1688
1689         net->mib.net_statistics = alloc_percpu(struct linux_mib);
1690         if (!net->mib.net_statistics)
1691                 goto err_net_mib;
1692         net->mib.udp_statistics = alloc_percpu(struct udp_mib);
1693         if (!net->mib.udp_statistics)
1694                 goto err_udp_mib;
1695         net->mib.udplite_statistics = alloc_percpu(struct udp_mib);
1696         if (!net->mib.udplite_statistics)
1697                 goto err_udplite_mib;
1698         net->mib.icmp_statistics = alloc_percpu(struct icmp_mib);
1699         if (!net->mib.icmp_statistics)
1700                 goto err_icmp_mib;
1701         net->mib.icmpmsg_statistics = kzalloc(sizeof(struct icmpmsg_mib),
1702                                               GFP_KERNEL);
1703         if (!net->mib.icmpmsg_statistics)
1704                 goto err_icmpmsg_mib;
1705
1706         tcp_mib_init(net);
1707         return 0;
1708
1709 err_icmpmsg_mib:
1710         free_percpu(net->mib.icmp_statistics);
1711 err_icmp_mib:
1712         free_percpu(net->mib.udplite_statistics);
1713 err_udplite_mib:
1714         free_percpu(net->mib.udp_statistics);
1715 err_udp_mib:
1716         free_percpu(net->mib.net_statistics);
1717 err_net_mib:
1718         free_percpu(net->mib.ip_statistics);
1719 err_ip_mib:
1720         free_percpu(net->mib.tcp_statistics);
1721 err_tcp_mib:
1722         return -ENOMEM;
1723 }
1724
1725 static __net_exit void ipv4_mib_exit_net(struct net *net)
1726 {
1727         kfree(net->mib.icmpmsg_statistics);
1728         free_percpu(net->mib.icmp_statistics);
1729         free_percpu(net->mib.udplite_statistics);
1730         free_percpu(net->mib.udp_statistics);
1731         free_percpu(net->mib.net_statistics);
1732         free_percpu(net->mib.ip_statistics);
1733         free_percpu(net->mib.tcp_statistics);
1734 }
1735
1736 static __net_initdata struct pernet_operations ipv4_mib_ops = {
1737         .init = ipv4_mib_init_net,
1738         .exit = ipv4_mib_exit_net,
1739 };
1740
1741 static int __init init_ipv4_mibs(void)
1742 {
1743         return register_pernet_subsys(&ipv4_mib_ops);
1744 }
1745
1746 static __net_init int inet_init_net(struct net *net)
1747 {
1748         /*
1749          * Set defaults for local port range
1750          */
1751         seqlock_init(&net->ipv4.ip_local_ports.lock);
1752         net->ipv4.ip_local_ports.range[0] =  32768;
1753         net->ipv4.ip_local_ports.range[1] =  60999;
1754
1755         seqlock_init(&net->ipv4.ping_group_range.lock);
1756         /*
1757          * Sane defaults - nobody may create ping sockets.
1758          * Boot scripts should set this to distro-specific group.
1759          */
1760         net->ipv4.ping_group_range.range[0] = make_kgid(&init_user_ns, 1);
1761         net->ipv4.ping_group_range.range[1] = make_kgid(&init_user_ns, 0);
1762
1763         /* Default values for sysctl-controlled parameters.
1764          * We set them here, in case sysctl is not compiled.
1765          */
1766         net->ipv4.sysctl_ip_default_ttl = IPDEFTTL;
1767         net->ipv4.sysctl_ip_dynaddr = 0;
1768         net->ipv4.sysctl_ip_early_demux = 1;
1769         net->ipv4.sysctl_udp_early_demux = 1;
1770         net->ipv4.sysctl_tcp_early_demux = 1;
1771 #ifdef CONFIG_SYSCTL
1772         net->ipv4.sysctl_ip_prot_sock = PROT_SOCK;
1773 #endif
1774
1775         /* Some igmp sysctl, whose values are always used */
1776         net->ipv4.sysctl_igmp_max_memberships = 20;
1777         net->ipv4.sysctl_igmp_max_msf = 10;
1778         /* IGMP reports for link-local multicast groups are enabled by default */
1779         net->ipv4.sysctl_igmp_llm_reports = 1;
1780         net->ipv4.sysctl_igmp_qrv = 2;
1781
1782         return 0;
1783 }
1784
1785 static __net_exit void inet_exit_net(struct net *net)
1786 {
1787 }
1788
1789 static __net_initdata struct pernet_operations af_inet_ops = {
1790         .init = inet_init_net,
1791         .exit = inet_exit_net,
1792 };
1793
1794 static int __init init_inet_pernet_ops(void)
1795 {
1796         return register_pernet_subsys(&af_inet_ops);
1797 }
1798
1799 static int ipv4_proc_init(void);
1800
1801 /*
1802  *      IP protocol layer initialiser
1803  */
1804
1805 static struct packet_offload ip_packet_offload __read_mostly = {
1806         .type = cpu_to_be16(ETH_P_IP),
1807         .callbacks = {
1808                 .gso_segment = inet_gso_segment,
1809                 .gro_receive = inet_gro_receive,
1810                 .gro_complete = inet_gro_complete,
1811         },
1812 };
1813
1814 static const struct net_offload ipip_offload = {
1815         .callbacks = {
1816                 .gso_segment    = inet_gso_segment,
1817                 .gro_receive    = ipip_gro_receive,
1818                 .gro_complete   = ipip_gro_complete,
1819         },
1820 };
1821
1822 static int __init ipip_offload_init(void)
1823 {
1824         return inet_add_offload(&ipip_offload, IPPROTO_IPIP);
1825 }
1826
1827 static int __init ipv4_offload_init(void)
1828 {
1829         /*
1830          * Add offloads
1831          */
1832         if (udpv4_offload_init() < 0)
1833                 pr_crit("%s: Cannot add UDP protocol offload\n", __func__);
1834         if (tcpv4_offload_init() < 0)
1835                 pr_crit("%s: Cannot add TCP protocol offload\n", __func__);
1836         if (ipip_offload_init() < 0)
1837                 pr_crit("%s: Cannot add IPIP protocol offload\n", __func__);
1838
1839         dev_add_offload(&ip_packet_offload);
1840         return 0;
1841 }
1842
1843 fs_initcall(ipv4_offload_init);
1844
1845 static struct packet_type ip_packet_type __read_mostly = {
1846         .type = cpu_to_be16(ETH_P_IP),
1847         .func = ip_rcv,
1848 };
1849
1850 static int __init inet_init(void)
1851 {
1852         struct inet_protosw *q;
1853         struct list_head *r;
1854         int rc = -EINVAL;
1855
1856         sock_skb_cb_check_size(sizeof(struct inet_skb_parm));
1857
1858         rc = proto_register(&tcp_prot, 1);
1859         if (rc)
1860                 goto out;
1861
1862         rc = proto_register(&udp_prot, 1);
1863         if (rc)
1864                 goto out_unregister_tcp_proto;
1865
1866         rc = proto_register(&raw_prot, 1);
1867         if (rc)
1868                 goto out_unregister_udp_proto;
1869
1870         rc = proto_register(&ping_prot, 1);
1871         if (rc)
1872                 goto out_unregister_raw_proto;
1873
1874         /*
1875          *      Tell SOCKET that we are alive...
1876          */
1877
1878         (void)sock_register(&inet_family_ops);
1879
1880 #ifdef CONFIG_SYSCTL
1881         ip_static_sysctl_init();
1882 #endif
1883
1884         /*
1885          *      Add all the base protocols.
1886          */
1887
1888         if (inet_add_protocol(&icmp_protocol, IPPROTO_ICMP) < 0)
1889                 pr_crit("%s: Cannot add ICMP protocol\n", __func__);
1890         if (inet_add_protocol(&udp_protocol, IPPROTO_UDP) < 0)
1891                 pr_crit("%s: Cannot add UDP protocol\n", __func__);
1892         if (inet_add_protocol(&tcp_protocol, IPPROTO_TCP) < 0)
1893                 pr_crit("%s: Cannot add TCP protocol\n", __func__);
1894 #ifdef CONFIG_IP_MULTICAST
1895         if (inet_add_protocol(&igmp_protocol, IPPROTO_IGMP) < 0)
1896                 pr_crit("%s: Cannot add IGMP protocol\n", __func__);
1897 #endif
1898
1899         /* Register the socket-side information for inet_create. */
1900         for (r = &inetsw[0]; r < &inetsw[SOCK_MAX]; ++r)
1901                 INIT_LIST_HEAD(r);
1902
1903         for (q = inetsw_array; q < &inetsw_array[INETSW_ARRAY_LEN]; ++q)
1904                 inet_register_protosw(q);
1905
1906         /*
1907          *      Set the ARP module up
1908          */
1909
1910         arp_init();
1911
1912         /*
1913          *      Set the IP module up
1914          */
1915
1916         ip_init();
1917
1918         /* Setup TCP slab cache for open requests. */
1919         tcp_init();
1920
1921         /* Setup UDP memory threshold */
1922         udp_init();
1923
1924         /* Add UDP-Lite (RFC 3828) */
1925         udplite4_register();
1926
1927         ping_init();
1928
1929         /*
1930          *      Set the ICMP layer up
1931          */
1932
1933         if (icmp_init() < 0)
1934                 panic("Failed to create the ICMP control socket.\n");
1935
1936         /*
1937          *      Initialise the multicast router
1938          */
1939 #if defined(CONFIG_IP_MROUTE)
1940         if (ip_mr_init())
1941                 pr_crit("%s: Cannot init ipv4 mroute\n", __func__);
1942 #endif
1943
1944         if (init_inet_pernet_ops())
1945                 pr_crit("%s: Cannot init ipv4 inet pernet ops\n", __func__);
1946         /*
1947          *      Initialise per-cpu ipv4 mibs
1948          */
1949
1950         if (init_ipv4_mibs())
1951                 pr_crit("%s: Cannot init ipv4 mibs\n", __func__);
1952
1953         ipv4_proc_init();
1954
1955         ipfrag_init();
1956
1957         dev_add_pack(&ip_packet_type);
1958
1959         ip_tunnel_core_init();
1960
1961         rc = 0;
1962 out:
1963         return rc;
1964 out_unregister_raw_proto:
1965         proto_unregister(&raw_prot);
1966 out_unregister_udp_proto:
1967         proto_unregister(&udp_prot);
1968 out_unregister_tcp_proto:
1969         proto_unregister(&tcp_prot);
1970         goto out;
1971 }
1972
1973 fs_initcall(inet_init);
1974
1975 /* ------------------------------------------------------------------------ */
1976
1977 #ifdef CONFIG_PROC_FS
1978 static int __init ipv4_proc_init(void)
1979 {
1980         int rc = 0;
1981
1982         if (raw_proc_init())
1983                 goto out_raw;
1984         if (tcp4_proc_init())
1985                 goto out_tcp;
1986         if (udp4_proc_init())
1987                 goto out_udp;
1988         if (ping_proc_init())
1989                 goto out_ping;
1990         if (ip_misc_proc_init())
1991                 goto out_misc;
1992 out:
1993         return rc;
1994 out_misc:
1995         ping_proc_exit();
1996 out_ping:
1997         udp4_proc_exit();
1998 out_udp:
1999         tcp4_proc_exit();
2000 out_tcp:
2001         raw_proc_exit();
2002 out_raw:
2003         rc = -ENOMEM;
2004         goto out;
2005 }
2006
2007 #else /* CONFIG_PROC_FS */
2008 static int __init ipv4_proc_init(void)
2009 {
2010         return 0;
2011 }
2012 #endif /* CONFIG_PROC_FS */