SAFE public projects git trees. - safe/jmp/linux-2.6/blob - 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, <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 #include <linux/err.h>
  69 #include <linux/errno.h>
  70 #include <linux/types.h>
  71 #include <linux/socket.h>
  72 #include <linux/in.h>
  73 #include <linux/kernel.h>
  74 #include <linux/module.h>
  75 #include <linux/sched.h>
  76 #include <linux/timer.h>
  77 #include <linux/string.h>
  78 #include <linux/sockios.h>
  79 #include <linux/net.h>
  80 #include <linux/capability.h>
  81 #include <linux/fcntl.h>
  82 #include <linux/mm.h>
  83 #include <linux/interrupt.h>
  84 #include <linux/stat.h>
  85 #include <linux/init.h>
  86 #include <linux/poll.h>
  87 #include <linux/netfilter_ipv4.h>
  88 #include <linux/random.h>
  89 #include <linux/slab.h>
  90
  91 #include <asm/uaccess.h>
  92 #include <asm/system.h>
  93
  94 #include <linux/inet.h>
  95 #include <linux/igmp.h>
  96 #include <linux/inetdevice.h>
  97 #include <linux/netdevice.h>
  98 #include <net/checksum.h>
  99 #include <net/ip.h>
 100 #include <net/protocol.h>
 101 #include <net/arp.h>
 102 #include <net/route.h>
 103 #include <net/ip_fib.h>
 104 #include <net/inet_connection_sock.h>
 105 #include <net/tcp.h>
 106 #include <net/udp.h>
 107 #include <net/udplite.h>
 108 #include <linux/skbuff.h>
 109 #include <net/sock.h>
 110 #include <net/raw.h>
 111 #include <net/icmp.h>
 112 #include <net/ipip.h>
 113 #include <net/inet_common.h>
 114 #include <net/xfrm.h>
 115 #include <net/net_namespace.h>
 116 #ifdef CONFIG_IP_MROUTE
 117 #include <linux/mroute.h>
 118 #endif
 119
 120
 121 /* The inetsw table contains everything that inet_create needs to
 122  * build a new socket.
 123  */
 124 static struct list_head inetsw[SOCK_MAX];
 125 static DEFINE_SPINLOCK(inetsw_lock);
 126
 127 struct ipv4_config ipv4_config;
 128 EXPORT_SYMBOL(ipv4_config);
 129
 130 /* New destruction routine */
 131
 132 void inet_sock_destruct(struct sock *sk)
 133 {
 134         struct inet_sock *inet = inet_sk(sk);
 135
 136         __skb_queue_purge(&sk->sk_receive_queue);
 137         __skb_queue_purge(&sk->sk_error_queue);
 138
 139         sk_mem_reclaim(sk);
 140
 141         if (sk->sk_type == SOCK_STREAM && sk->sk_state != TCP_CLOSE) {
 142                 pr_err("Attempt to release TCP socket in state %d %p\n",
 143                        sk->sk_state, sk);
 144                 return;
 145         }
 146         if (!sock_flag(sk, SOCK_DEAD)) {
 147                 pr_err("Attempt to release alive inet socket %p\n", sk);
 148                 return;
 149         }
 150
 151         WARN_ON(atomic_read(&sk->sk_rmem_alloc));
 152         WARN_ON(atomic_read(&sk->sk_wmem_alloc));
 153         WARN_ON(sk->sk_wmem_queued);
 154         WARN_ON(sk->sk_forward_alloc);
 155
 156         kfree(inet->opt);
 157         dst_release(sk->sk_dst_cache);
 158         sk_refcnt_debug_dec(sk);
 159 }
 160 EXPORT_SYMBOL(inet_sock_destruct);
 161
 162 /*
 163  *      The routines beyond this point handle the behaviour of an AF_INET
 164  *      socket object. Mostly it punts to the subprotocols of IP to do
 165  *      the work.
 166  */
 167
 168 /*
 169  *      Automatically bind an unbound socket.
 170  */
 171
 172 static int inet_autobind(struct sock *sk)
 173 {
 174         struct inet_sock *inet;
 175         /* We may need to bind the socket. */
 176         lock_sock(sk);
 177         inet = inet_sk(sk);
 178         if (!inet->inet_num) {
 179                 if (sk->sk_prot->get_port(sk, 0)) {
 180                         release_sock(sk);
 181                         return -EAGAIN;
 182                 }
 183                 inet->inet_sport = htons(inet->inet_num);
 184         }
 185         release_sock(sk);
 186         return 0;
 187 }
 188
 189 /*
 190  *      Move a socket into listening state.
 191  */
 192 int inet_listen(struct socket *sock, int backlog)
 193 {
 194         struct sock *sk = sock->sk;
 195         unsigned char old_state;
 196         int err;
 197
 198         lock_sock(sk);
 199
 200         err = -EINVAL;
 201         if (sock->state != SS_UNCONNECTED || sock->type != SOCK_STREAM)
 202                 goto out;
 203
 204         old_state = sk->sk_state;
 205         if (!((1 << old_state) & (TCPF_CLOSE | TCPF_LISTEN)))
 206                 goto out;
 207
 208         /* Really, if the socket is already in listen state
 209          * we can only allow the backlog to be adjusted.
 210          */
 211         if (old_state != TCP_LISTEN) {
 212                 err = inet_csk_listen_start(sk, backlog);
 213                 if (err)
 214                         goto out;
 215         }
 216         sk->sk_max_ack_backlog = backlog;
 217         err = 0;
 218
 219 out:
 220         release_sock(sk);
 221         return err;
 222 }
 223 EXPORT_SYMBOL(inet_listen);
 224
 225 u32 inet_ehash_secret __read_mostly;
 226 EXPORT_SYMBOL(inet_ehash_secret);
 227
 228 /*
 229  * inet_ehash_secret must be set exactly once
 230  * Instead of using a dedicated spinlock, we (ab)use inetsw_lock
 231  */
 232 void build_ehash_secret(void)
 233 {
 234         u32 rnd;
 235         do {
 236                 get_random_bytes(&rnd, sizeof(rnd));
 237         } while (rnd == 0);
 238         spin_lock_bh(&inetsw_lock);
 239         if (!inet_ehash_secret)
 240                 inet_ehash_secret = rnd;
 241         spin_unlock_bh(&inetsw_lock);
 242 }
 243 EXPORT_SYMBOL(build_ehash_secret);
 244
 245 static inline int inet_netns_ok(struct net *net, int protocol)
 246 {
 247         int hash;
 248         const struct net_protocol *ipprot;
 249
 250         if (net_eq(net, &init_net))
 251                 return 1;
 252
 253         hash = protocol & (MAX_INET_PROTOS - 1);
 254         ipprot = rcu_dereference(inet_protos[hash]);
 255
 256         if (ipprot == NULL)
 257                 /* raw IP is OK */
 258                 return 1;
 259         return ipprot->netns_ok;
 260 }
 261
 262 /*
 263  *      Create an inet socket.
 264  */
 265
 266 static int inet_create(struct net *net, struct socket *sock, int protocol,
 267                        int kern)
 268 {
 269         struct sock *sk;
 270         struct inet_protosw *answer;
 271         struct inet_sock *inet;
 272         struct proto *answer_prot;
 273         unsigned char answer_flags;
 274         char answer_no_check;
 275         int try_loading_module = 0;
 276         int err;
 277
 278         if (unlikely(!inet_ehash_secret))
 279                 if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM)
 280                         build_ehash_secret();
 281
 282         sock->state = SS_UNCONNECTED;
 283
 284         /* Look for the requested type/protocol pair. */
 285 lookup_protocol:
 286         err = -ESOCKTNOSUPPORT;
 287         rcu_read_lock();
 288         list_for_each_entry_rcu(answer, &inetsw[sock->type], list) {
 289
 290                 err = 0;
 291                 /* Check the non-wild match. */
 292                 if (protocol == answer->protocol) {
 293                         if (protocol != IPPROTO_IP)
 294                                 break;
 295                 } else {
 296                         /* Check for the two wild cases. */
 297                         if (IPPROTO_IP == protocol) {
 298                                 protocol = answer->protocol;
 299                                 break;
 300                         }
 301                         if (IPPROTO_IP == answer->protocol)
 302                                 break;
 303                 }
 304                 err = -EPROTONOSUPPORT;
 305         }
 306
 307         if (unlikely(err)) {
 308                 if (try_loading_module < 2) {
 309                         rcu_read_unlock();
 310                         /*
 311                          * Be more specific, e.g. net-pf-2-proto-132-type-1
 312                          * (net-pf-PF_INET-proto-IPPROTO_SCTP-type-SOCK_STREAM)
 313                          */
 314                         if (++try_loading_module == 1)
 315                                 request_module("net-pf-%d-proto-%d-type-%d",
 316                                                PF_INET, protocol, sock->type);
 317                         /*
 318                          * Fall back to generic, e.g. net-pf-2-proto-132
 319                          * (net-pf-PF_INET-proto-IPPROTO_SCTP)
 320                          */
 321                         else
 322                                 request_module("net-pf-%d-proto-%d",
 323                                                PF_INET, protocol);
 324                         goto lookup_protocol;
 325                 } else
 326                         goto out_rcu_unlock;
 327         }
 328
 329         err = -EPERM;
 330         if (sock->type == SOCK_RAW && !kern && !capable(CAP_NET_RAW))
 331                 goto out_rcu_unlock;
 332
 333         err = -EAFNOSUPPORT;
 334         if (!inet_netns_ok(net, protocol))
 335                 goto out_rcu_unlock;
 336
 337         sock->ops = answer->ops;
 338         answer_prot = answer->prot;
 339         answer_no_check = answer->no_check;
 340         answer_flags = answer->flags;
 341         rcu_read_unlock();
 342
 343         WARN_ON(answer_prot->slab == NULL);
 344
 345         err = -ENOBUFS;
 346         sk = sk_alloc(net, PF_INET, GFP_KERNEL, answer_prot);
 347         if (sk == NULL)
 348                 goto out;
 349
 350         err = 0;
 351         sk->sk_no_check = answer_no_check;
 352         if (INET_PROTOSW_REUSE & answer_flags)
 353                 sk->sk_reuse = 1;
 354
 355         inet = inet_sk(sk);
 356         inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
 357
 358         if (SOCK_RAW == sock->type) {
 359                 inet->inet_num = protocol;
 360                 if (IPPROTO_RAW == protocol)
 361                         inet->hdrincl = 1;
 362         }
 363
 364         if (ipv4_config.no_pmtu_disc)
 365                 inet->pmtudisc = IP_PMTUDISC_DONT;
 366         else
 367                 inet->pmtudisc = IP_PMTUDISC_WANT;
 368
 369         inet->inet_id = 0;
 370
 371         sock_init_data(sock, sk);
 372
 373         sk->sk_destruct    = inet_sock_destruct;
 374         sk->sk_protocol    = protocol;
 375         sk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
 376
 377         inet->uc_ttl    = -1;
 378         inet->mc_loop   = 1;
 379         inet->mc_ttl    = 1;
 380         inet->mc_all    = 1;
 381         inet->mc_index  = 0;
 382         inet->mc_list   = NULL;
 383
 384         sk_refcnt_debug_inc(sk);
 385
 386         if (inet->inet_num) {
 387                 /* It assumes that any protocol which allows
 388                  * the user to assign a number at socket
 389                  * creation time automatically
 390                  * shares.
 391                  */
 392                 inet->inet_sport = htons(inet->inet_num);
 393                 /* Add to protocol hash chains. */
 394                 sk->sk_prot->hash(sk);
 395         }
 396
 397         if (sk->sk_prot->init) {
 398                 err = sk->sk_prot->init(sk);
 399                 if (err)
 400                         sk_common_release(sk);
 401         }
 402 out:
 403         return err;
 404 out_rcu_unlock:
 405         rcu_read_unlock();
 406         goto out;
 407 }
 408
 409
 410 /*
 411  *      The peer socket should always be NULL (or else). When we call this
 412  *      function we are destroying the object and from then on nobody
 413  *      should refer to it.
 414  */
 415 int inet_release(struct socket *sock)
 416 {
 417         struct sock *sk = sock->sk;
 418
 419         if (sk) {
 420                 long timeout;
 421
 422                 /* Applications forget to leave groups before exiting */
 423                 ip_mc_drop_socket(sk);
 424
 425                 /* If linger is set, we don't return until the close
 426                  * is complete.  Otherwise we return immediately. The
 427                  * actually closing is done the same either way.
 428                  *
 429                  * If the close is due to the process exiting, we never
 430                  * linger..
 431                  */
 432                 timeout = 0;
 433                 if (sock_flag(sk, SOCK_LINGER) &&
 434                     !(current->flags & PF_EXITING))
 435                         timeout = sk->sk_lingertime;
 436                 sock->sk = NULL;
 437                 sk->sk_prot->close(sk, timeout);
 438         }
 439         return 0;
 440 }
 441 EXPORT_SYMBOL(inet_release);
 442
 443 /* It is off by default, see below. */
 444 int sysctl_ip_nonlocal_bind __read_mostly;
 445 EXPORT_SYMBOL(sysctl_ip_nonlocal_bind);
 446
 447 int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 448 {
 449         struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
 450         struct sock *sk = sock->sk;
 451         struct inet_sock *inet = inet_sk(sk);
 452         unsigned short snum;
 453         int chk_addr_ret;
 454         int err;
 455
 456         /* If the socket has its own bind function then use it. (RAW) */
 457         if (sk->sk_prot->bind) {
 458                 err = sk->sk_prot->bind(sk, uaddr, addr_len);
 459                 goto out;
 460         }
 461         err = -EINVAL;
 462         if (addr_len < sizeof(struct sockaddr_in))
 463                 goto out;
 464
 465         chk_addr_ret = inet_addr_type(sock_net(sk), addr->sin_addr.s_addr);
 466
 467         /* Not specified by any standard per-se, however it breaks too
 468          * many applications when removed.  It is unfortunate since
 469          * allowing applications to make a non-local bind solves
 470          * several problems with systems using dynamic addressing.
 471          * (ie. your servers still start up even if your ISDN link
 472          *  is temporarily down)
 473          */
 474         err = -EADDRNOTAVAIL;
 475         if (!sysctl_ip_nonlocal_bind &&
 476             !(inet->freebind || inet->transparent) &&
 477             addr->sin_addr.s_addr != htonl(INADDR_ANY) &&
 478             chk_addr_ret != RTN_LOCAL &&
 479             chk_addr_ret != RTN_MULTICAST &&
 480             chk_addr_ret != RTN_BROADCAST)
 481                 goto out;
 482
 483         snum = ntohs(addr->sin_port);
 484         err = -EACCES;
 485         if (snum && snum < PROT_SOCK && !capable(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 (sk->sk_prot->get_port(sk, snum)) {
 508                 inet->inet_saddr = inet->inet_rcv_saddr = 0;
 509                 err = -EADDRINUSE;
 510                 goto out_release_sock;
 511         }
 512
 513         if (inet->inet_rcv_saddr)
 514                 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
 515         if (snum)
 516                 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
 517         inet->inet_sport = htons(inet->inet_num);
 518         inet->inet_daddr = 0;
 519         inet->inet_dport = 0;
 520         sk_dst_reset(sk);
 521         err = 0;
 522 out_release_sock:
 523         release_sock(sk);
 524 out:
 525         return err;
 526 }
 527 EXPORT_SYMBOL(inet_bind);
 528
 529 int inet_dgram_connect(struct socket *sock, struct sockaddr * uaddr,
 530                        int addr_len, int flags)
 531 {
 532         struct sock *sk = sock->sk;
 533
 534         if (addr_len < sizeof(uaddr->sa_family))
 535                 return -EINVAL;
 536         if (uaddr->sa_family == AF_UNSPEC)
 537                 return sk->sk_prot->disconnect(sk, flags);
 538
 539         if (!inet_sk(sk)->inet_num && inet_autobind(sk))
 540                 return -EAGAIN;
 541         return sk->sk_prot->connect(sk, (struct sockaddr *)uaddr, addr_len);
 542 }
 543 EXPORT_SYMBOL(inet_dgram_connect);
 544
 545 static long inet_wait_for_connect(struct sock *sk, long timeo)
 546 {
 547         DEFINE_WAIT(wait);
 548
 549         prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
 550
 551         /* Basic assumption: if someone sets sk->sk_err, he _must_
 552          * change state of the socket from TCP_SYN_*.
 553          * Connect() does not allow to get error notifications
 554          * without closing the socket.
 555          */
 556         while ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
 557                 release_sock(sk);
 558                 timeo = schedule_timeout(timeo);
 559                 lock_sock(sk);
 560                 if (signal_pending(current) || !timeo)
 561                         break;
 562                 prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
 563         }
 564         finish_wait(sk->sk_sleep, &wait);
 565         return timeo;
 566 }
 567
 568 /*
 569  *      Connect to a remote host. There is regrettably still a little
 570  *      TCP 'magic' in here.
 571  */
 572 int inet_stream_connect(struct socket *sock, struct sockaddr *uaddr,
 573                         int addr_len, int flags)
 574 {
 575         struct sock *sk = sock->sk;
 576         int err;
 577         long timeo;
 578
 579         if (addr_len < sizeof(uaddr->sa_family))
 580                 return -EINVAL;
 581
 582         lock_sock(sk);
 583
 584         if (uaddr->sa_family == AF_UNSPEC) {
 585                 err = sk->sk_prot->disconnect(sk, flags);
 586                 sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
 587                 goto out;
 588         }
 589
 590         switch (sock->state) {
 591         default:
 592                 err = -EINVAL;
 593                 goto out;
 594         case SS_CONNECTED:
 595                 err = -EISCONN;
 596                 goto out;
 597         case SS_CONNECTING:
 598                 err = -EALREADY;
 599                 /* Fall out of switch with err, set for this state */
 600                 break;
 601         case SS_UNCONNECTED:
 602                 err = -EISCONN;
 603                 if (sk->sk_state != TCP_CLOSE)
 604                         goto out;
 605
 606                 err = sk->sk_prot->connect(sk, uaddr, addr_len);
 607                 if (err < 0)
 608                         goto out;
 609
 610                 sock->state = SS_CONNECTING;
 611
 612                 /* Just entered SS_CONNECTING state; the only
 613                  * difference is that return value in non-blocking
 614                  * case is EINPROGRESS, rather than EALREADY.
 615                  */
 616                 err = -EINPROGRESS;
 617                 break;
 618         }
 619
 620         timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
 621
 622         if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
 623                 /* Error code is set above */
 624                 if (!timeo || !inet_wait_for_connect(sk, timeo))
 625                         goto out;
 626
 627                 err = sock_intr_errno(timeo);
 628                 if (signal_pending(current))
 629                         goto out;
 630         }
 631
 632         /* Connection was closed by RST, timeout, ICMP error
 633          * or another process disconnected us.
 634          */
 635         if (sk->sk_state == TCP_CLOSE)
 636                 goto sock_error;
 637
 638         /* sk->sk_err may be not zero now, if RECVERR was ordered by user
 639          * and error was received after socket entered established state.
 640          * Hence, it is handled normally after connect() return successfully.
 641          */
 642
 643         sock->state = SS_CONNECTED;
 644         err = 0;
 645 out:
 646         release_sock(sk);
 647         return err;
 648
 649 sock_error:
 650         err = sock_error(sk) ? : -ECONNABORTED;
 651         sock->state = SS_UNCONNECTED;
 652         if (sk->sk_prot->disconnect(sk, flags))
 653                 sock->state = SS_DISCONNECTING;
 654         goto out;
 655 }
 656 EXPORT_SYMBOL(inet_stream_connect);
 657
 658 /*
 659  *      Accept a pending connection. The TCP layer now gives BSD semantics.
 660  */
 661
 662 int inet_accept(struct socket *sock, struct socket *newsock, int flags)
 663 {
 664         struct sock *sk1 = sock->sk;
 665         int err = -EINVAL;
 666         struct sock *sk2 = sk1->sk_prot->accept(sk1, flags, &err);
 667
 668         if (!sk2)
 669                 goto do_err;
 670
 671         lock_sock(sk2);
 672
 673         WARN_ON(!((1 << sk2->sk_state) &
 674                   (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT | TCPF_CLOSE)));
 675
 676         sock_graft(sk2, newsock);
 677
 678         newsock->state = SS_CONNECTED;
 679         err = 0;
 680         release_sock(sk2);
 681 do_err:
 682         return err;
 683 }
 684 EXPORT_SYMBOL(inet_accept);
 685
 686
 687 /*
 688  *      This does both peername and sockname.
 689  */
 690 int inet_getname(struct socket *sock, struct sockaddr *uaddr,
 691                         int *uaddr_len, int peer)
 692 {
 693         struct sock *sk         = sock->sk;
 694         struct inet_sock *inet  = inet_sk(sk);
 695         DECLARE_SOCKADDR(struct sockaddr_in *, sin, uaddr);
 696
 697         sin->sin_family = AF_INET;
 698         if (peer) {
 699                 if (!inet->inet_dport ||
 700                     (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
 701                      peer == 1))
 702                         return -ENOTCONN;
 703                 sin->sin_port = inet->inet_dport;
 704                 sin->sin_addr.s_addr = inet->inet_daddr;
 705         } else {
 706                 __be32 addr = inet->inet_rcv_saddr;
 707                 if (!addr)
 708                         addr = inet->inet_saddr;
 709                 sin->sin_port = inet->inet_sport;
 710                 sin->sin_addr.s_addr = addr;
 711         }
 712         memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
 713         *uaddr_len = sizeof(*sin);
 714         return 0;
 715 }
 716 EXPORT_SYMBOL(inet_getname);
 717
 718 int inet_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
 719                  size_t size)
 720 {
 721         struct sock *sk = sock->sk;
 722
 723         /* We may need to bind the socket. */
 724         if (!inet_sk(sk)->inet_num && inet_autobind(sk))
 725                 return -EAGAIN;
 726
 727         return sk->sk_prot->sendmsg(iocb, sk, msg, size);
 728 }
 729 EXPORT_SYMBOL(inet_sendmsg);
 730
 731
 732 static ssize_t inet_sendpage(struct socket *sock, struct page *page, int offset,
 733                              size_t size, int flags)
 734 {
 735         struct sock *sk = sock->sk;
 736
 737         /* We may need to bind the socket. */
 738         if (!inet_sk(sk)->inet_num && inet_autobind(sk))
 739                 return -EAGAIN;
 740
 741         if (sk->sk_prot->sendpage)
 742                 return sk->sk_prot->sendpage(sk, page, offset, size, flags);
 743         return sock_no_sendpage(sock, page, offset, size, flags);
 744 }
 745
 746
 747 int inet_shutdown(struct socket *sock, int how)
 748 {
 749         struct sock *sk = sock->sk;
 750         int err = 0;
 751
 752         /* This should really check to make sure
 753          * the socket is a TCP socket. (WHY AC...)
 754          */
 755         how++; /* maps 0->1 has the advantage of making bit 1 rcvs and
 756                        1->2 bit 2 snds.
 757                        2->3 */
 758         if ((how & ~SHUTDOWN_MASK) || !how)     /* MAXINT->0 */
 759                 return -EINVAL;
 760
 761         lock_sock(sk);
 762         if (sock->state == SS_CONNECTING) {
 763                 if ((1 << sk->sk_state) &
 764                     (TCPF_SYN_SENT | TCPF_SYN_RECV | TCPF_CLOSE))
 765                         sock->state = SS_DISCONNECTING;
 766                 else
 767                         sock->state = SS_CONNECTED;
 768         }
 769
 770         switch (sk->sk_state) {
 771         case TCP_CLOSE:
 772                 err = -ENOTCONN;
 773                 /* Hack to wake up other listeners, who can poll for
 774                    POLLHUP, even on eg. unconnected UDP sockets -- RR */
 775         default:
 776                 sk->sk_shutdown |= how;
 777                 if (sk->sk_prot->shutdown)
 778                         sk->sk_prot->shutdown(sk, how);
 779                 break;
 780
 781         /* Remaining two branches are temporary solution for missing
 782          * close() in multithreaded environment. It is _not_ a good idea,
 783          * but we have no choice until close() is repaired at VFS level.
 784          */
 785         case TCP_LISTEN:
 786                 if (!(how & RCV_SHUTDOWN))
 787                         break;
 788                 /* Fall through */
 789         case TCP_SYN_SENT:
 790                 err = sk->sk_prot->disconnect(sk, O_NONBLOCK);
 791                 sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
 792                 break;
 793         }
 794
 795         /* Wake up anyone sleeping in poll. */
 796         sk->sk_state_change(sk);
 797         release_sock(sk);
 798         return err;
 799 }
 800 EXPORT_SYMBOL(inet_shutdown);
 801
 802 /*
 803  *      ioctl() calls you can issue on an INET socket. Most of these are
 804  *      device configuration and stuff and very rarely used. Some ioctls
 805  *      pass on to the socket itself.
 806  *
 807  *      NOTE: I like the idea of a module for the config stuff. ie ifconfig
 808  *      loads the devconfigure module does its configuring and unloads it.
 809  *      There's a good 20K of config code hanging around the kernel.
 810  */
 811
 812 int inet_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 813 {
 814         struct sock *sk = sock->sk;
 815         int err = 0;
 816         struct net *net = sock_net(sk);
 817
 818         switch (cmd) {
 819         case SIOCGSTAMP:
 820                 err = sock_get_timestamp(sk, (struct timeval __user *)arg);
 821                 break;
 822         case SIOCGSTAMPNS:
 823                 err = sock_get_timestampns(sk, (struct timespec __user *)arg);
 824                 break;
 825         case SIOCADDRT:
 826         case SIOCDELRT:
 827         case SIOCRTMSG:
 828                 err = ip_rt_ioctl(net, cmd, (void __user *)arg);
 829                 break;
 830         case SIOCDARP:
 831         case SIOCGARP:
 832         case SIOCSARP:
 833                 err = arp_ioctl(net, cmd, (void __user *)arg);
 834                 break;
 835         case SIOCGIFADDR:
 836         case SIOCSIFADDR:
 837         case SIOCGIFBRDADDR:
 838         case SIOCSIFBRDADDR:
 839         case SIOCGIFNETMASK:
 840         case SIOCSIFNETMASK:
 841         case SIOCGIFDSTADDR:
 842         case SIOCSIFDSTADDR:
 843         case SIOCSIFPFLAGS:
 844         case SIOCGIFPFLAGS:
 845         case SIOCSIFFLAGS:
 846                 err = devinet_ioctl(net, cmd, (void __user *)arg);
 847                 break;
 848         default:
 849                 if (sk->sk_prot->ioctl)
 850                         err = sk->sk_prot->ioctl(sk, cmd, arg);
 851                 else
 852                         err = -ENOIOCTLCMD;
 853                 break;
 854         }
 855         return err;
 856 }
 857 EXPORT_SYMBOL(inet_ioctl);
 858
 859 const struct proto_ops inet_stream_ops = {
 860         .family            = PF_INET,
 861         .owner             = THIS_MODULE,
 862         .release           = inet_release,
 863         .bind              = inet_bind,
 864         .connect           = inet_stream_connect,
 865         .socketpair        = sock_no_socketpair,
 866         .accept            = inet_accept,
 867         .getname           = inet_getname,
 868         .poll              = tcp_poll,
 869         .ioctl             = inet_ioctl,
 870         .listen            = inet_listen,
 871         .shutdown          = inet_shutdown,
 872         .setsockopt        = sock_common_setsockopt,
 873         .getsockopt        = sock_common_getsockopt,
 874         .sendmsg           = tcp_sendmsg,
 875         .recvmsg           = sock_common_recvmsg,
 876         .mmap              = sock_no_mmap,
 877         .sendpage          = tcp_sendpage,
 878         .splice_read       = tcp_splice_read,
 879 #ifdef CONFIG_COMPAT
 880         .compat_setsockopt = compat_sock_common_setsockopt,
 881         .compat_getsockopt = compat_sock_common_getsockopt,
 882 #endif
 883 };
 884 EXPORT_SYMBOL(inet_stream_ops);
 885
 886 const struct proto_ops inet_dgram_ops = {
 887         .family            = PF_INET,
 888         .owner             = THIS_MODULE,
 889         .release           = inet_release,
 890         .bind              = inet_bind,
 891         .connect           = inet_dgram_connect,
 892         .socketpair        = sock_no_socketpair,
 893         .accept            = sock_no_accept,
 894         .getname           = inet_getname,
 895         .poll              = udp_poll,
 896         .ioctl             = inet_ioctl,
 897         .listen            = sock_no_listen,
 898         .shutdown          = inet_shutdown,
 899         .setsockopt        = sock_common_setsockopt,
 900         .getsockopt        = sock_common_getsockopt,
 901         .sendmsg           = inet_sendmsg,
 902         .recvmsg           = sock_common_recvmsg,
 903         .mmap              = sock_no_mmap,
 904         .sendpage          = inet_sendpage,
 905 #ifdef CONFIG_COMPAT
 906         .compat_setsockopt = compat_sock_common_setsockopt,
 907         .compat_getsockopt = compat_sock_common_getsockopt,
 908 #endif
 909 };
 910 EXPORT_SYMBOL(inet_dgram_ops);
 911
 912 /*
 913  * For SOCK_RAW sockets; should be the same as inet_dgram_ops but without
 914  * udp_poll
 915  */
 916 static const struct proto_ops inet_sockraw_ops = {
 917         .family            = PF_INET,
 918         .owner             = THIS_MODULE,
 919         .release           = inet_release,
 920         .bind              = inet_bind,
 921         .connect           = inet_dgram_connect,
 922         .socketpair        = sock_no_socketpair,
 923         .accept            = sock_no_accept,
 924         .getname           = inet_getname,
 925         .poll              = datagram_poll,
 926         .ioctl             = inet_ioctl,
 927         .listen            = sock_no_listen,
 928         .shutdown          = inet_shutdown,
 929         .setsockopt        = sock_common_setsockopt,
 930         .getsockopt        = sock_common_getsockopt,
 931         .sendmsg           = inet_sendmsg,
 932         .recvmsg           = sock_common_recvmsg,
 933         .mmap              = sock_no_mmap,
 934         .sendpage          = inet_sendpage,
 935 #ifdef CONFIG_COMPAT
 936         .compat_setsockopt = compat_sock_common_setsockopt,
 937         .compat_getsockopt = compat_sock_common_getsockopt,
 938 #endif
 939 };
 940
 941 static const struct net_proto_family inet_family_ops = {
 942         .family = PF_INET,
 943         .create = inet_create,
 944         .owner  = THIS_MODULE,
 945 };
 946
 947 /* Upon startup we insert all the elements in inetsw_array[] into
 948  * the linked list inetsw.
 949  */
 950 static struct inet_protosw inetsw_array[] =
 951 {
 952         {
 953                 .type =       SOCK_STREAM,
 954                 .protocol =   IPPROTO_TCP,
 955                 .prot =       &tcp_prot,
 956                 .ops =        &inet_stream_ops,
 957                 .no_check =   0,
 958                 .flags =      INET_PROTOSW_PERMANENT |
 959                               INET_PROTOSW_ICSK,
 960         },
 961
 962         {
 963                 .type =       SOCK_DGRAM,
 964                 .protocol =   IPPROTO_UDP,
 965                 .prot =       &udp_prot,
 966                 .ops =        &inet_dgram_ops,
 967                 .no_check =   UDP_CSUM_DEFAULT,
 968                 .flags =      INET_PROTOSW_PERMANENT,
 969        },
 970
 971
 972        {
 973                .type =       SOCK_RAW,
 974                .protocol =   IPPROTO_IP,        /* wild card */
 975                .prot =       &raw_prot,
 976                .ops =        &inet_sockraw_ops,
 977                .no_check =   UDP_CSUM_DEFAULT,
 978                .flags =      INET_PROTOSW_REUSE,
 979        }
 980 };
 981
 982 #define INETSW_ARRAY_LEN ARRAY_SIZE(inetsw_array)
 983
 984 void inet_register_protosw(struct inet_protosw *p)
 985 {
 986         struct list_head *lh;
 987         struct inet_protosw *answer;
 988         int protocol = p->protocol;
 989         struct list_head *last_perm;
 990
 991         spin_lock_bh(&inetsw_lock);
 992
 993         if (p->type >= SOCK_MAX)
 994                 goto out_illegal;
 995
 996         /* If we are trying to override a permanent protocol, bail. */
 997         answer = NULL;
 998         last_perm = &inetsw[p->type];
 999         list_for_each(lh, &inetsw[p->type]) {
1000                 answer = list_entry(lh, struct inet_protosw, list);
1001
1002                 /* Check only the non-wild match. */
1003                 if (INET_PROTOSW_PERMANENT & answer->flags) {
1004                         if (protocol == answer->protocol)
1005                                 break;
1006                         last_perm = lh;
1007                 }
1008
1009                 answer = NULL;
1010         }
1011         if (answer)
1012                 goto out_permanent;
1013
1014         /* Add the new entry after the last permanent entry if any, so that
1015          * the new entry does not override a permanent entry when matched with
1016          * a wild-card protocol. But it is allowed to override any existing
1017          * non-permanent entry.  This means that when we remove this entry, the
1018          * system automatically returns to the old behavior.
1019          */
1020         list_add_rcu(&p->list, last_perm);
1021 out:
1022         spin_unlock_bh(&inetsw_lock);
1023
1024         return;
1025
1026 out_permanent:
1027         printk(KERN_ERR "Attempt to override permanent protocol %d.\n",
1028                protocol);
1029         goto out;
1030
1031 out_illegal:
1032         printk(KERN_ERR
1033                "Ignoring attempt to register invalid socket type %d.\n",
1034                p->type);
1035         goto out;
1036 }
1037 EXPORT_SYMBOL(inet_register_protosw);
1038
1039 void inet_unregister_protosw(struct inet_protosw *p)
1040 {
1041         if (INET_PROTOSW_PERMANENT & p->flags) {
1042                 printk(KERN_ERR
1043                        "Attempt to unregister permanent protocol %d.\n",
1044                        p->protocol);
1045         } else {
1046                 spin_lock_bh(&inetsw_lock);
1047                 list_del_rcu(&p->list);
1048                 spin_unlock_bh(&inetsw_lock);
1049
1050                 synchronize_net();
1051         }
1052 }
1053 EXPORT_SYMBOL(inet_unregister_protosw);
1054
1055 /*
1056  *      Shall we try to damage output packets if routing dev changes?
1057  */
1058
1059 int sysctl_ip_dynaddr __read_mostly;
1060
1061 static int inet_sk_reselect_saddr(struct sock *sk)
1062 {
1063         struct inet_sock *inet = inet_sk(sk);
1064         int err;
1065         struct rtable *rt;
1066         __be32 old_saddr = inet->inet_saddr;
1067         __be32 new_saddr;
1068         __be32 daddr = inet->inet_daddr;
1069
1070         if (inet->opt && inet->opt->srr)
1071                 daddr = inet->opt->faddr;
1072
1073         /* Query new route. */
1074         err = ip_route_connect(&rt, daddr, 0,
1075                                RT_CONN_FLAGS(sk),
1076                                sk->sk_bound_dev_if,
1077                                sk->sk_protocol,
1078                                inet->inet_sport, inet->inet_dport, sk, 0);
1079         if (err)
1080                 return err;
1081
1082         sk_setup_caps(sk, &rt->u.dst);
1083
1084         new_saddr = rt->rt_src;
1085
1086         if (new_saddr == old_saddr)
1087                 return 0;
1088
1089         if (sysctl_ip_dynaddr > 1) {
1090                 printk(KERN_INFO "%s(): shifting inet->saddr from %pI4 to %pI4\n",
1091                        __func__, &old_saddr, &new_saddr);
1092         }
1093
1094         inet->inet_saddr = inet->inet_rcv_saddr = new_saddr;
1095
1096         /*
1097          * XXX The only one ugly spot where we need to
1098          * XXX really change the sockets identity after
1099          * XXX it has entered the hashes. -DaveM
1100          *
1101          * Besides that, it does not check for connection
1102          * uniqueness. Wait for troubles.
1103          */
1104         __sk_prot_rehash(sk);
1105         return 0;
1106 }
1107
1108 int inet_sk_rebuild_header(struct sock *sk)
1109 {
1110         struct inet_sock *inet = inet_sk(sk);
1111         struct rtable *rt = (struct rtable *)__sk_dst_check(sk, 0);
1112         __be32 daddr;
1113         int err;
1114
1115         /* Route is OK, nothing to do. */
1116         if (rt)
1117                 return 0;
1118
1119         /* Reroute. */
1120         daddr = inet->inet_daddr;
1121         if (inet->opt && inet->opt->srr)
1122                 daddr = inet->opt->faddr;
1123 {
1124         struct flowi fl = {
1125                 .oif = sk->sk_bound_dev_if,
1126                 .mark = sk->sk_mark,
1127                 .nl_u = {
1128                         .ip4_u = {
1129                                 .daddr  = daddr,
1130                                 .saddr  = inet->inet_saddr,
1131                                 .tos    = RT_CONN_FLAGS(sk),
1132                         },
1133                 },
1134                 .proto = sk->sk_protocol,
1135                 .flags = inet_sk_flowi_flags(sk),
1136                 .uli_u = {
1137                         .ports = {
1138                                 .sport = inet->inet_sport,
1139                                 .dport = inet->inet_dport,
1140                         },
1141                 },
1142         };
1143
1144         security_sk_classify_flow(sk, &fl);
1145         err = ip_route_output_flow(sock_net(sk), &rt, &fl, sk, 0);
1146 }
1147         if (!err)
1148                 sk_setup_caps(sk, &rt->u.dst);
1149         else {
1150                 /* Routing failed... */
1151                 sk->sk_route_caps = 0;
1152                 /*
1153                  * Other protocols have to map its equivalent state to TCP_SYN_SENT.
1154                  * DCCP maps its DCCP_REQUESTING state to TCP_SYN_SENT. -acme
1155                  */
1156                 if (!sysctl_ip_dynaddr ||
1157                     sk->sk_state != TCP_SYN_SENT ||
1158                     (sk->sk_userlocks & SOCK_BINDADDR_LOCK) ||
1159                     (err = inet_sk_reselect_saddr(sk)) != 0)
1160                         sk->sk_err_soft = -err;
1161         }
1162
1163         return err;
1164 }
1165 EXPORT_SYMBOL(inet_sk_rebuild_header);
1166
1167 static int inet_gso_send_check(struct sk_buff *skb)
1168 {
1169         struct iphdr *iph;
1170         const struct net_protocol *ops;
1171         int proto;
1172         int ihl;
1173         int err = -EINVAL;
1174
1175         if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
1176                 goto out;
1177
1178         iph = ip_hdr(skb);
1179         ihl = iph->ihl * 4;
1180         if (ihl < sizeof(*iph))
1181                 goto out;
1182
1183         if (unlikely(!pskb_may_pull(skb, ihl)))
1184                 goto out;
1185
1186         __skb_pull(skb, ihl);
1187         skb_reset_transport_header(skb);
1188         iph = ip_hdr(skb);
1189         proto = iph->protocol & (MAX_INET_PROTOS - 1);
1190         err = -EPROTONOSUPPORT;
1191
1192         rcu_read_lock();
1193         ops = rcu_dereference(inet_protos[proto]);
1194         if (likely(ops && ops->gso_send_check))
1195                 err = ops->gso_send_check(skb);
1196         rcu_read_unlock();
1197
1198 out:
1199         return err;
1200 }
1201
1202 static struct sk_buff *inet_gso_segment(struct sk_buff *skb, int features)
1203 {
1204         struct sk_buff *segs = ERR_PTR(-EINVAL);
1205         struct iphdr *iph;
1206         const struct net_protocol *ops;
1207         int proto;
1208         int ihl;
1209         int id;
1210         unsigned int offset = 0;
1211
1212         if (!(features & NETIF_F_V4_CSUM))
1213                 features &= ~NETIF_F_SG;
1214
1215         if (unlikely(skb_shinfo(skb)->gso_type &
1216                      ~(SKB_GSO_TCPV4 |
1217                        SKB_GSO_UDP |
1218                        SKB_GSO_DODGY |
1219                        SKB_GSO_TCP_ECN |
1220                        0)))
1221                 goto out;
1222
1223         if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
1224                 goto out;
1225
1226         iph = ip_hdr(skb);
1227         ihl = iph->ihl * 4;
1228         if (ihl < sizeof(*iph))
1229                 goto out;
1230
1231         if (unlikely(!pskb_may_pull(skb, ihl)))
1232                 goto out;
1233
1234         __skb_pull(skb, ihl);
1235         skb_reset_transport_header(skb);
1236         iph = ip_hdr(skb);
1237         id = ntohs(iph->id);
1238         proto = iph->protocol & (MAX_INET_PROTOS - 1);
1239         segs = ERR_PTR(-EPROTONOSUPPORT);
1240
1241         rcu_read_lock();
1242         ops = rcu_dereference(inet_protos[proto]);
1243         if (likely(ops && ops->gso_segment))
1244                 segs = ops->gso_segment(skb, features);
1245         rcu_read_unlock();
1246
1247         if (!segs || IS_ERR(segs))
1248                 goto out;
1249
1250         skb = segs;
1251         do {
1252                 iph = ip_hdr(skb);
1253                 if (proto == IPPROTO_UDP) {
1254                         iph->id = htons(id);
1255                         iph->frag_off = htons(offset >> 3);
1256                         if (skb->next != NULL)
1257                                 iph->frag_off |= htons(IP_MF);
1258                         offset += (skb->len - skb->mac_len - iph->ihl * 4);
1259                 } else
1260                         iph->id = htons(id++);
1261                 iph->tot_len = htons(skb->len - skb->mac_len);
1262                 iph->check = 0;
1263                 iph->check = ip_fast_csum(skb_network_header(skb), iph->ihl);
1264         } while ((skb = skb->next));
1265
1266 out:
1267         return segs;
1268 }
1269
1270 static struct sk_buff **inet_gro_receive(struct sk_buff **head,
1271                                          struct sk_buff *skb)
1272 {
1273         const struct net_protocol *ops;
1274         struct sk_buff **pp = NULL;
1275         struct sk_buff *p;
1276         struct iphdr *iph;
1277         unsigned int hlen;
1278         unsigned int off;
1279         unsigned int id;
1280         int flush = 1;
1281         int proto;
1282
1283         off = skb_gro_offset(skb);
1284         hlen = off + sizeof(*iph);
1285         iph = skb_gro_header_fast(skb, off);
1286         if (skb_gro_header_hard(skb, hlen)) {
1287                 iph = skb_gro_header_slow(skb, hlen, off);
1288                 if (unlikely(!iph))
1289                         goto out;
1290         }
1291
1292         proto = iph->protocol & (MAX_INET_PROTOS - 1);
1293
1294         rcu_read_lock();
1295         ops = rcu_dereference(inet_protos[proto]);
1296         if (!ops || !ops->gro_receive)
1297                 goto out_unlock;
1298
1299         if (*(u8 *)iph != 0x45)
1300                 goto out_unlock;
1301
1302         if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1303                 goto out_unlock;
1304
1305         id = ntohl(*(u32 *)&iph->id);
1306         flush = (u16)((ntohl(*(u32 *)iph) ^ skb_gro_len(skb)) | (id ^ IP_DF));
1307         id >>= 16;
1308
1309         for (p = *head; p; p = p->next) {
1310                 struct iphdr *iph2;
1311
1312                 if (!NAPI_GRO_CB(p)->same_flow)
1313                         continue;
1314
1315                 iph2 = ip_hdr(p);
1316
1317                 if ((iph->protocol ^ iph2->protocol) |
1318                     (iph->tos ^ iph2->tos) |
1319                     (iph->saddr ^ iph2->saddr) |
1320                     (iph->daddr ^ iph2->daddr)) {
1321                         NAPI_GRO_CB(p)->same_flow = 0;
1322                         continue;
1323                 }
1324
1325                 /* All fields must match except length and checksum. */
1326                 NAPI_GRO_CB(p)->flush |=
1327                         (iph->ttl ^ iph2->ttl) |
1328                         ((u16)(ntohs(iph2->id) + NAPI_GRO_CB(p)->count) ^ id);
1329
1330                 NAPI_GRO_CB(p)->flush |= flush;
1331         }
1332
1333         NAPI_GRO_CB(skb)->flush |= flush;
1334         skb_gro_pull(skb, sizeof(*iph));
1335         skb_set_transport_header(skb, skb_gro_offset(skb));
1336
1337         pp = ops->gro_receive(head, skb);
1338
1339 out_unlock:
1340         rcu_read_unlock();
1341
1342 out:
1343         NAPI_GRO_CB(skb)->flush |= flush;
1344
1345         return pp;
1346 }
1347
1348 static int inet_gro_complete(struct sk_buff *skb)
1349 {
1350         const struct net_protocol *ops;
1351         struct iphdr *iph = ip_hdr(skb);
1352         int proto = iph->protocol & (MAX_INET_PROTOS - 1);
1353         int err = -ENOSYS;
1354         __be16 newlen = htons(skb->len - skb_network_offset(skb));
1355
1356         csum_replace2(&iph->check, iph->tot_len, newlen);
1357         iph->tot_len = newlen;
1358
1359         rcu_read_lock();
1360         ops = rcu_dereference(inet_protos[proto]);
1361         if (WARN_ON(!ops || !ops->gro_complete))
1362                 goto out_unlock;
1363
1364         err = ops->gro_complete(skb);
1365
1366 out_unlock:
1367         rcu_read_unlock();
1368
1369         return err;
1370 }
1371
1372 int inet_ctl_sock_create(struct sock **sk, unsigned short family,
1373                          unsigned short type, unsigned char protocol,
1374                          struct net *net)
1375 {
1376         struct socket *sock;
1377         int rc = sock_create_kern(family, type, protocol, &sock);
1378
1379         if (rc == 0) {
1380                 *sk = sock->sk;
1381                 (*sk)->sk_allocation = GFP_ATOMIC;
1382                 /*
1383                  * Unhash it so that IP input processing does not even see it,
1384                  * we do not wish this socket to see incoming packets.
1385                  */
1386                 (*sk)->sk_prot->unhash(*sk);
1387
1388                 sk_change_net(*sk, net);
1389         }
1390         return rc;
1391 }
1392 EXPORT_SYMBOL_GPL(inet_ctl_sock_create);
1393
1394 unsigned long snmp_fold_field(void __percpu *mib[], int offt)
1395 {
1396         unsigned long res = 0;
1397         int i;
1398
1399         for_each_possible_cpu(i) {
1400                 res += *(((unsigned long *) per_cpu_ptr(mib[0], i)) + offt);
1401                 res += *(((unsigned long *) per_cpu_ptr(mib[1], i)) + offt);
1402         }
1403         return res;
1404 }
1405 EXPORT_SYMBOL_GPL(snmp_fold_field);
1406
1407 int snmp_mib_init(void __percpu *ptr[2], size_t mibsize)
1408 {
1409         BUG_ON(ptr == NULL);
1410         ptr[0] = __alloc_percpu(mibsize, __alignof__(unsigned long long));
1411         if (!ptr[0])
1412                 goto err0;
1413         ptr[1] = __alloc_percpu(mibsize, __alignof__(unsigned long long));
1414         if (!ptr[1])
1415                 goto err1;
1416         return 0;
1417 err1:
1418         free_percpu(ptr[0]);
1419         ptr[0] = NULL;
1420 err0:
1421         return -ENOMEM;
1422 }
1423 EXPORT_SYMBOL_GPL(snmp_mib_init);
1424
1425 void snmp_mib_free(void __percpu *ptr[2])
1426 {
1427         BUG_ON(ptr == NULL);
1428         free_percpu(ptr[0]);
1429         free_percpu(ptr[1]);
1430         ptr[0] = ptr[1] = NULL;
1431 }
1432 EXPORT_SYMBOL_GPL(snmp_mib_free);
1433
1434 #ifdef CONFIG_IP_MULTICAST
1435 static const struct net_protocol igmp_protocol = {
1436         .handler =      igmp_rcv,
1437         .netns_ok =     1,
1438 };
1439 #endif
1440
1441 static const struct net_protocol tcp_protocol = {
1442         .handler =      tcp_v4_rcv,
1443         .err_handler =  tcp_v4_err,
1444         .gso_send_check = tcp_v4_gso_send_check,
1445         .gso_segment =  tcp_tso_segment,
1446         .gro_receive =  tcp4_gro_receive,
1447         .gro_complete = tcp4_gro_complete,
1448         .no_policy =    1,
1449         .netns_ok =     1,
1450 };
1451
1452 static const struct net_protocol udp_protocol = {
1453         .handler =      udp_rcv,
1454         .err_handler =  udp_err,
1455         .gso_send_check = udp4_ufo_send_check,
1456         .gso_segment = udp4_ufo_fragment,
1457         .no_policy =    1,
1458         .netns_ok =     1,
1459 };
1460
1461 static const struct net_protocol icmp_protocol = {
1462         .handler =      icmp_rcv,
1463         .no_policy =    1,
1464         .netns_ok =     1,
1465 };
1466
1467 static __net_init int ipv4_mib_init_net(struct net *net)
1468 {
1469         if (snmp_mib_init((void __percpu **)net->mib.tcp_statistics,
1470                           sizeof(struct tcp_mib)) < 0)
1471                 goto err_tcp_mib;
1472         if (snmp_mib_init((void __percpu **)net->mib.ip_statistics,
1473                           sizeof(struct ipstats_mib)) < 0)
1474                 goto err_ip_mib;
1475         if (snmp_mib_init((void __percpu **)net->mib.net_statistics,
1476                           sizeof(struct linux_mib)) < 0)
1477                 goto err_net_mib;
1478         if (snmp_mib_init((void __percpu **)net->mib.udp_statistics,
1479                           sizeof(struct udp_mib)) < 0)
1480                 goto err_udp_mib;
1481         if (snmp_mib_init((void __percpu **)net->mib.udplite_statistics,
1482                           sizeof(struct udp_mib)) < 0)
1483                 goto err_udplite_mib;
1484         if (snmp_mib_init((void __percpu **)net->mib.icmp_statistics,
1485                           sizeof(struct icmp_mib)) < 0)
1486                 goto err_icmp_mib;
1487         if (snmp_mib_init((void __percpu **)net->mib.icmpmsg_statistics,
1488                           sizeof(struct icmpmsg_mib)) < 0)
1489                 goto err_icmpmsg_mib;
1490
1491         tcp_mib_init(net);
1492         return 0;
1493
1494 err_icmpmsg_mib:
1495         snmp_mib_free((void __percpu **)net->mib.icmp_statistics);
1496 err_icmp_mib:
1497         snmp_mib_free((void __percpu **)net->mib.udplite_statistics);
1498 err_udplite_mib:
1499         snmp_mib_free((void __percpu **)net->mib.udp_statistics);
1500 err_udp_mib:
1501         snmp_mib_free((void __percpu **)net->mib.net_statistics);
1502 err_net_mib:
1503         snmp_mib_free((void __percpu **)net->mib.ip_statistics);
1504 err_ip_mib:
1505         snmp_mib_free((void __percpu **)net->mib.tcp_statistics);
1506 err_tcp_mib:
1507         return -ENOMEM;
1508 }
1509
1510 static __net_exit void ipv4_mib_exit_net(struct net *net)
1511 {
1512         snmp_mib_free((void __percpu **)net->mib.icmpmsg_statistics);
1513         snmp_mib_free((void __percpu **)net->mib.icmp_statistics);
1514         snmp_mib_free((void __percpu **)net->mib.udplite_statistics);
1515         snmp_mib_free((void __percpu **)net->mib.udp_statistics);
1516         snmp_mib_free((void __percpu **)net->mib.net_statistics);
1517         snmp_mib_free((void __percpu **)net->mib.ip_statistics);
1518         snmp_mib_free((void __percpu **)net->mib.tcp_statistics);
1519 }
1520
1521 static __net_initdata struct pernet_operations ipv4_mib_ops = {
1522         .init = ipv4_mib_init_net,
1523         .exit = ipv4_mib_exit_net,
1524 };
1525
1526 static int __init init_ipv4_mibs(void)
1527 {
1528         return register_pernet_subsys(&ipv4_mib_ops);
1529 }
1530
1531 static int ipv4_proc_init(void);
1532
1533 /*
1534  *      IP protocol layer initialiser
1535  */
1536
1537 static struct packet_type ip_packet_type __read_mostly = {
1538         .type = cpu_to_be16(ETH_P_IP),
1539         .func = ip_rcv,
1540         .gso_send_check = inet_gso_send_check,
1541         .gso_segment = inet_gso_segment,
1542         .gro_receive = inet_gro_receive,
1543         .gro_complete = inet_gro_complete,
1544 };
1545
1546 static int __init inet_init(void)
1547 {
1548         struct sk_buff *dummy_skb;
1549         struct inet_protosw *q;
1550         struct list_head *r;
1551         int rc = -EINVAL;
1552
1553         BUILD_BUG_ON(sizeof(struct inet_skb_parm) > sizeof(dummy_skb->cb));
1554
1555         rc = proto_register(&tcp_prot, 1);
1556         if (rc)
1557                 goto out;
1558
1559         rc = proto_register(&udp_prot, 1);
1560         if (rc)
1561                 goto out_unregister_tcp_proto;
1562
1563         rc = proto_register(&raw_prot, 1);
1564         if (rc)
1565                 goto out_unregister_udp_proto;
1566
1567         /*
1568          *      Tell SOCKET that we are alive...
1569          */
1570
1571         (void)sock_register(&inet_family_ops);
1572
1573 #ifdef CONFIG_SYSCTL
1574         ip_static_sysctl_init();
1575 #endif
1576
1577         /*
1578          *      Add all the base protocols.
1579          */
1580
1581         if (inet_add_protocol(&icmp_protocol, IPPROTO_ICMP) < 0)
1582                 printk(KERN_CRIT "inet_init: Cannot add ICMP protocol\n");
1583         if (inet_add_protocol(&udp_protocol, IPPROTO_UDP) < 0)
1584                 printk(KERN_CRIT "inet_init: Cannot add UDP protocol\n");
1585         if (inet_add_protocol(&tcp_protocol, IPPROTO_TCP) < 0)
1586                 printk(KERN_CRIT "inet_init: Cannot add TCP protocol\n");
1587 #ifdef CONFIG_IP_MULTICAST
1588         if (inet_add_protocol(&igmp_protocol, IPPROTO_IGMP) < 0)
1589                 printk(KERN_CRIT "inet_init: Cannot add IGMP protocol\n");
1590 #endif
1591
1592         /* Register the socket-side information for inet_create. */
1593         for (r = &inetsw[0]; r < &inetsw[SOCK_MAX]; ++r)
1594                 INIT_LIST_HEAD(r);
1595
1596         for (q = inetsw_array; q < &inetsw_array[INETSW_ARRAY_LEN]; ++q)
1597                 inet_register_protosw(q);
1598
1599         /*
1600          *      Set the ARP module up
1601          */
1602
1603         arp_init();
1604
1605         /*
1606          *      Set the IP module up
1607          */
1608
1609         ip_init();
1610
1611         tcp_v4_init();
1612
1613         /* Setup TCP slab cache for open requests. */
1614         tcp_init();
1615
1616         /* Setup UDP memory threshold */
1617         udp_init();
1618
1619         /* Add UDP-Lite (RFC 3828) */
1620         udplite4_register();
1621
1622         /*
1623          *      Set the ICMP layer up
1624          */
1625
1626         if (icmp_init() < 0)
1627                 panic("Failed to create the ICMP control socket.\n");
1628
1629         /*
1630          *      Initialise the multicast router
1631          */
1632 #if defined(CONFIG_IP_MROUTE)
1633         if (ip_mr_init())
1634                 printk(KERN_CRIT "inet_init: Cannot init ipv4 mroute\n");
1635 #endif
1636         /*
1637          *      Initialise per-cpu ipv4 mibs
1638          */
1639
1640         if (init_ipv4_mibs())
1641                 printk(KERN_CRIT "inet_init: Cannot init ipv4 mibs\n");
1642
1643         ipv4_proc_init();
1644
1645         ipfrag_init();
1646
1647         dev_add_pack(&ip_packet_type);
1648
1649         rc = 0;
1650 out:
1651         return rc;
1652 out_unregister_udp_proto:
1653         proto_unregister(&udp_prot);
1654 out_unregister_tcp_proto:
1655         proto_unregister(&tcp_prot);
1656         goto out;
1657 }
1658
1659 fs_initcall(inet_init);
1660
1661 /* ------------------------------------------------------------------------ */
1662
1663 #ifdef CONFIG_PROC_FS
1664 static int __init ipv4_proc_init(void)
1665 {
1666         int rc = 0;
1667
1668         if (raw_proc_init())
1669                 goto out_raw;
1670         if (tcp4_proc_init())
1671                 goto out_tcp;
1672         if (udp4_proc_init())
1673                 goto out_udp;
1674         if (ip_misc_proc_init())
1675                 goto out_misc;
1676 out:
1677         return rc;
1678 out_misc:
1679         udp4_proc_exit();
1680 out_udp:
1681         tcp4_proc_exit();
1682 out_tcp:
1683         raw_proc_exit();
1684 out_raw:
1685         rc = -ENOMEM;
1686         goto out;
1687 }
1688
1689 #else /* CONFIG_PROC_FS */
1690 static int __init ipv4_proc_init(void)
1691 {
1692         return 0;
1693 }
1694 #endif /* CONFIG_PROC_FS */
1695
1696 MODULE_ALIAS_NETPROTO(PF_INET);
1697