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 #ifdef CONFIG_ANDROID_PARANOID_NETWORK
 121 #include <linux/android_aid.h>
 122 #endif
 123
 124 /* The inetsw table contains everything that inet_create needs to
 125  * build a new socket.
 126  */
 127 static struct list_head inetsw[SOCK_MAX];
 128 static DEFINE_SPINLOCK(inetsw_lock);
 129
 130 struct ipv4_config ipv4_config;
 131 EXPORT_SYMBOL(ipv4_config);
 132
 133 /* New destruction routine */
 134
 135 void inet_sock_destruct(struct sock *sk)
 136 {
 137         struct inet_sock *inet = inet_sk(sk);
 138
 139         __skb_queue_purge(&sk->sk_receive_queue);
 140         __skb_queue_purge(&sk->sk_error_queue);
 141
 142         sk_mem_reclaim(sk);
 143
 144         if (sk->sk_type == SOCK_STREAM && sk->sk_state != TCP_CLOSE) {
 145                 pr_err("Attempt to release TCP socket in state %d %p\n",
 146                        sk->sk_state, sk);
 147                 return;
 148         }
 149         if (!sock_flag(sk, SOCK_DEAD)) {
 150                 pr_err("Attempt to release alive inet socket %p\n", sk);
 151                 return;
 152         }
 153
 154         WARN_ON(atomic_read(&sk->sk_rmem_alloc));
 155         WARN_ON(atomic_read(&sk->sk_wmem_alloc));
 156         WARN_ON(sk->sk_wmem_queued);
 157         WARN_ON(sk->sk_forward_alloc);
 158
 159         kfree(inet->opt);
 160         dst_release(rcu_dereference_check(sk->sk_dst_cache, 1));
 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;
 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                 err = inet_csk_listen_start(sk, backlog);
 216                 if (err)
 217                         goto out;
 218         }
 219         sk->sk_max_ack_backlog = backlog;
 220         err = 0;
 221
 222 out:
 223         release_sock(sk);
 224         return err;
 225 }
 226 EXPORT_SYMBOL(inet_listen);
 227
 228 u32 inet_ehash_secret __read_mostly;
 229 EXPORT_SYMBOL(inet_ehash_secret);
 230
 231 /*
 232  * inet_ehash_secret must be set exactly once
 233  * Instead of using a dedicated spinlock, we (ab)use inetsw_lock
 234  */
 235 void build_ehash_secret(void)
 236 {
 237         u32 rnd;
 238         do {
 239                 get_random_bytes(&rnd, sizeof(rnd));
 240         } while (rnd == 0);
 241         spin_lock_bh(&inetsw_lock);
 242         if (!inet_ehash_secret)
 243                 inet_ehash_secret = rnd;
 244         spin_unlock_bh(&inetsw_lock);
 245 }
 246 EXPORT_SYMBOL(build_ehash_secret);
 247
 248 static inline int inet_netns_ok(struct net *net, int protocol)
 249 {
 250         int hash;
 251         const struct net_protocol *ipprot;
 252
 253         if (net_eq(net, &init_net))
 254                 return 1;
 255
 256         hash = protocol & (MAX_INET_PROTOS - 1);
 257         ipprot = rcu_dereference(inet_protos[hash]);
 258
 259         if (ipprot == NULL)
 260                 /* raw IP is OK */
 261                 return 1;
 262         return ipprot->netns_ok;
 263 }
 264
 265 #ifdef CONFIG_ANDROID_PARANOID_NETWORK
 266 static inline int current_has_network(void)
 267 {
 268         return (!current_euid() || in_egroup_p(AID_INET) ||
 269                 in_egroup_p(AID_NET_RAW));
 270 }
 271 static inline int current_has_cap(int cap)
 272 {
 273         if (cap == CAP_NET_RAW && in_egroup_p(AID_NET_RAW))
 274                 return 1;
 275         return capable(cap);
 276 }
 277 # else
 278 static inline int current_has_network(void)
 279 {
 280         return 1;
 281 }
 282 static inline int current_has_cap(int cap)
 283 {
 284         return capable(cap);
 285 }
 286 #endif
 287
 288 /*
 289  *      Create an inet socket.
 290  */
 291
 292 static int inet_create(struct net *net, struct socket *sock, int protocol,
 293                        int kern)
 294 {
 295         struct sock *sk;
 296         struct inet_protosw *answer;
 297         struct inet_sock *inet;
 298         struct proto *answer_prot;
 299         unsigned char answer_flags;
 300         char answer_no_check;
 301         int try_loading_module = 0;
 302         int err;
 303
 304         if (!current_has_network())
 305                 return -EACCES;
 306
 307         if (unlikely(!inet_ehash_secret))
 308                 if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM)
 309                         build_ehash_secret();
 310
 311         sock->state = SS_UNCONNECTED;
 312
 313         /* Look for the requested type/protocol pair. */
 314 lookup_protocol:
 315         err = -ESOCKTNOSUPPORT;
 316         rcu_read_lock();
 317         list_for_each_entry_rcu(answer, &inetsw[sock->type], list) {
 318
 319                 err = 0;
 320                 /* Check the non-wild match. */
 321                 if (protocol == answer->protocol) {
 322                         if (protocol != IPPROTO_IP)
 323                                 break;
 324                 } else {
 325                         /* Check for the two wild cases. */
 326                         if (IPPROTO_IP == protocol) {
 327                                 protocol = answer->protocol;
 328                                 break;
 329                         }
 330                         if (IPPROTO_IP == answer->protocol)
 331                                 break;
 332                 }
 333                 err = -EPROTONOSUPPORT;
 334         }
 335
 336         if (unlikely(err)) {
 337                 if (try_loading_module < 2) {
 338                         rcu_read_unlock();
 339                         /*
 340                          * Be more specific, e.g. net-pf-2-proto-132-type-1
 341                          * (net-pf-PF_INET-proto-IPPROTO_SCTP-type-SOCK_STREAM)
 342                          */
 343                         if (++try_loading_module == 1)
 344                                 request_module("net-pf-%d-proto-%d-type-%d",
 345                                                PF_INET, protocol, sock->type);
 346                         /*
 347                          * Fall back to generic, e.g. net-pf-2-proto-132
 348                          * (net-pf-PF_INET-proto-IPPROTO_SCTP)
 349                          */
 350                         else
 351                                 request_module("net-pf-%d-proto-%d",
 352                                                PF_INET, protocol);
 353                         goto lookup_protocol;
 354                 } else
 355                         goto out_rcu_unlock;
 356         }
 357
 358         err = -EPERM;
 359         if (sock->type == SOCK_RAW && !kern && !current_has_cap(CAP_NET_RAW))
 360                 goto out_rcu_unlock;
 361
 362         err = -EAFNOSUPPORT;
 363         if (!inet_netns_ok(net, protocol))
 364                 goto out_rcu_unlock;
 365
 366         sock->ops = answer->ops;
 367         answer_prot = answer->prot;
 368         answer_no_check = answer->no_check;
 369         answer_flags = answer->flags;
 370         rcu_read_unlock();
 371
 372         WARN_ON(answer_prot->slab == NULL);
 373
 374         err = -ENOBUFS;
 375         sk = sk_alloc(net, PF_INET, GFP_KERNEL, answer_prot);
 376         if (sk == NULL)
 377                 goto out;
 378
 379         err = 0;
 380         sk->sk_no_check = answer_no_check;
 381         if (INET_PROTOSW_REUSE & answer_flags)
 382                 sk->sk_reuse = 1;
 383
 384         inet = inet_sk(sk);
 385         inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
 386
 387         inet->nodefrag = 0;
 388
 389         if (SOCK_RAW == sock->type) {
 390                 inet->inet_num = protocol;
 391                 if (IPPROTO_RAW == protocol)
 392                         inet->hdrincl = 1;
 393         }
 394
 395         if (ipv4_config.no_pmtu_disc)
 396                 inet->pmtudisc = IP_PMTUDISC_DONT;
 397         else
 398                 inet->pmtudisc = IP_PMTUDISC_WANT;
 399
 400         inet->inet_id = 0;
 401
 402         sock_init_data(sock, sk);
 403
 404         sk->sk_destruct    = inet_sock_destruct;
 405         sk->sk_protocol    = protocol;
 406         sk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
 407
 408         inet->uc_ttl    = -1;
 409         inet->mc_loop   = 1;
 410         inet->mc_ttl    = 1;
 411         inet->mc_all    = 1;
 412         inet->mc_index  = 0;
 413         inet->mc_list   = NULL;
 414
 415         sk_refcnt_debug_inc(sk);
 416
 417         if (inet->inet_num) {
 418                 /* It assumes that any protocol which allows
 419                  * the user to assign a number at socket
 420                  * creation time automatically
 421                  * shares.
 422                  */
 423                 inet->inet_sport = htons(inet->inet_num);
 424                 /* Add to protocol hash chains. */
 425                 sk->sk_prot->hash(sk);
 426         }
 427
 428         if (sk->sk_prot->init) {
 429                 err = sk->sk_prot->init(sk);
 430                 if (err)
 431                         sk_common_release(sk);
 432         }
 433 out:
 434         return err;
 435 out_rcu_unlock:
 436         rcu_read_unlock();
 437         goto out;
 438 }
 439
 440
 441 /*
 442  *      The peer socket should always be NULL (or else). When we call this
 443  *      function we are destroying the object and from then on nobody
 444  *      should refer to it.
 445  */
 446 int inet_release(struct socket *sock)
 447 {
 448         struct sock *sk = sock->sk;
 449
 450         if (sk) {
 451                 long timeout;
 452
 453                 sock_rps_reset_flow(sk);
 454
 455                 /* Applications forget to leave groups before exiting */
 456                 ip_mc_drop_socket(sk);
 457
 458                 /* If linger is set, we don't return until the close
 459                  * is complete.  Otherwise we return immediately. The
 460                  * actually closing is done the same either way.
 461                  *
 462                  * If the close is due to the process exiting, we never
 463                  * linger..
 464                  */
 465                 timeout = 0;
 466                 if (sock_flag(sk, SOCK_LINGER) &&
 467                     !(current->flags & PF_EXITING))
 468                         timeout = sk->sk_lingertime;
 469                 sock->sk = NULL;
 470                 sk->sk_prot->close(sk, timeout);
 471         }
 472         return 0;
 473 }
 474 EXPORT_SYMBOL(inet_release);
 475
 476 /* It is off by default, see below. */
 477 int sysctl_ip_nonlocal_bind __read_mostly;
 478 EXPORT_SYMBOL(sysctl_ip_nonlocal_bind);
 479
 480 int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 481 {
 482         struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
 483         struct sock *sk = sock->sk;
 484         struct inet_sock *inet = inet_sk(sk);
 485         unsigned short snum;
 486         int chk_addr_ret;
 487         int err;
 488
 489         /* If the socket has its own bind function then use it. (RAW) */
 490         if (sk->sk_prot->bind) {
 491                 err = sk->sk_prot->bind(sk, uaddr, addr_len);
 492                 goto out;
 493         }
 494         err = -EINVAL;
 495         if (addr_len < sizeof(struct sockaddr_in))
 496                 goto out;
 497
 498         chk_addr_ret = inet_addr_type(sock_net(sk), addr->sin_addr.s_addr);
 499
 500         /* Not specified by any standard per-se, however it breaks too
 501          * many applications when removed.  It is unfortunate since
 502          * allowing applications to make a non-local bind solves
 503          * several problems with systems using dynamic addressing.
 504          * (ie. your servers still start up even if your ISDN link
 505          *  is temporarily down)
 506          */
 507         err = -EADDRNOTAVAIL;
 508         if (!sysctl_ip_nonlocal_bind &&
 509             !(inet->freebind || inet->transparent) &&
 510             addr->sin_addr.s_addr != htonl(INADDR_ANY) &&
 511             chk_addr_ret != RTN_LOCAL &&
 512             chk_addr_ret != RTN_MULTICAST &&
 513             chk_addr_ret != RTN_BROADCAST)
 514                 goto out;
 515
 516         snum = ntohs(addr->sin_port);
 517         err = -EACCES;
 518         if (snum && snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
 519                 goto out;
 520
 521         /*      We keep a pair of addresses. rcv_saddr is the one
 522          *      used by hash lookups, and saddr is used for transmit.
 523          *
 524          *      In the BSD API these are the same except where it
 525          *      would be illegal to use them (multicast/broadcast) in
 526          *      which case the sending device address is used.
 527          */
 528         lock_sock(sk);
 529
 530         /* Check these errors (active socket, double bind). */
 531         err = -EINVAL;
 532         if (sk->sk_state != TCP_CLOSE || inet->inet_num)
 533                 goto out_release_sock;
 534
 535         inet->inet_rcv_saddr = inet->inet_saddr = addr->sin_addr.s_addr;
 536         if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST)
 537                 inet->inet_saddr = 0;  /* Use device */
 538
 539         /* Make sure we are allowed to bind here. */
 540         if (sk->sk_prot->get_port(sk, snum)) {
 541                 inet->inet_saddr = inet->inet_rcv_saddr = 0;
 542                 err = -EADDRINUSE;
 543                 goto out_release_sock;
 544         }
 545
 546         if (inet->inet_rcv_saddr)
 547                 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
 548         if (snum)
 549                 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
 550         inet->inet_sport = htons(inet->inet_num);
 551         inet->inet_daddr = 0;
 552         inet->inet_dport = 0;
 553         sk_dst_reset(sk);
 554         err = 0;
 555 out_release_sock:
 556         release_sock(sk);
 557 out:
 558         return err;
 559 }
 560 EXPORT_SYMBOL(inet_bind);
 561
 562 int inet_dgram_connect(struct socket *sock, struct sockaddr * uaddr,
 563                        int addr_len, int flags)
 564 {
 565         struct sock *sk = sock->sk;
 566
 567         if (addr_len < sizeof(uaddr->sa_family))
 568                 return -EINVAL;
 569         if (uaddr->sa_family == AF_UNSPEC)
 570                 return sk->sk_prot->disconnect(sk, flags);
 571
 572         if (!inet_sk(sk)->inet_num && inet_autobind(sk))
 573                 return -EAGAIN;
 574         return sk->sk_prot->connect(sk, (struct sockaddr *)uaddr, addr_len);
 575 }
 576 EXPORT_SYMBOL(inet_dgram_connect);
 577
 578 static long inet_wait_for_connect(struct sock *sk, long timeo)
 579 {
 580         DEFINE_WAIT(wait);
 581
 582         prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
 583
 584         /* Basic assumption: if someone sets sk->sk_err, he _must_
 585          * change state of the socket from TCP_SYN_*.
 586          * Connect() does not allow to get error notifications
 587          * without closing the socket.
 588          */
 589         while ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
 590                 release_sock(sk);
 591                 timeo = schedule_timeout(timeo);
 592                 lock_sock(sk);
 593                 if (signal_pending(current) || !timeo)
 594                         break;
 595                 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
 596         }
 597         finish_wait(sk_sleep(sk), &wait);
 598         return timeo;
 599 }
 600
 601 /*
 602  *      Connect to a remote host. There is regrettably still a little
 603  *      TCP 'magic' in here.
 604  */
 605 int inet_stream_connect(struct socket *sock, struct sockaddr *uaddr,
 606                         int addr_len, int flags)
 607 {
 608         struct sock *sk = sock->sk;
 609         int err;
 610         long timeo;
 611
 612         if (addr_len < sizeof(uaddr->sa_family))
 613                 return -EINVAL;
 614
 615         lock_sock(sk);
 616
 617         if (uaddr->sa_family == AF_UNSPEC) {
 618                 err = sk->sk_prot->disconnect(sk, flags);
 619                 sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
 620                 goto out;
 621         }
 622
 623         switch (sock->state) {
 624         default:
 625                 err = -EINVAL;
 626                 goto out;
 627         case SS_CONNECTED:
 628                 err = -EISCONN;
 629                 goto out;
 630         case SS_CONNECTING:
 631                 err = -EALREADY;
 632                 /* Fall out of switch with err, set for this state */
 633                 break;
 634         case SS_UNCONNECTED:
 635                 err = -EISCONN;
 636                 if (sk->sk_state != TCP_CLOSE)
 637                         goto out;
 638
 639                 err = sk->sk_prot->connect(sk, uaddr, addr_len);
 640                 if (err < 0)
 641                         goto out;
 642
 643                 sock->state = SS_CONNECTING;
 644
 645                 /* Just entered SS_CONNECTING state; the only
 646                  * difference is that return value in non-blocking
 647                  * case is EINPROGRESS, rather than EALREADY.
 648                  */
 649                 err = -EINPROGRESS;
 650                 break;
 651         }
 652
 653         timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
 654
 655         if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
 656                 /* Error code is set above */
 657                 if (!timeo || !inet_wait_for_connect(sk, timeo))
 658                         goto out;
 659
 660                 err = sock_intr_errno(timeo);
 661                 if (signal_pending(current))
 662                         goto out;
 663         }
 664
 665         /* Connection was closed by RST, timeout, ICMP error
 666          * or another process disconnected us.
 667          */
 668         if (sk->sk_state == TCP_CLOSE)
 669                 goto sock_error;
 670
 671         /* sk->sk_err may be not zero now, if RECVERR was ordered by user
 672          * and error was received after socket entered established state.
 673          * Hence, it is handled normally after connect() return successfully.
 674          */
 675
 676         sock->state = SS_CONNECTED;
 677         err = 0;
 678 out:
 679         release_sock(sk);
 680         return err;
 681
 682 sock_error:
 683         err = sock_error(sk) ? : -ECONNABORTED;
 684         sock->state = SS_UNCONNECTED;
 685         if (sk->sk_prot->disconnect(sk, flags))
 686                 sock->state = SS_DISCONNECTING;
 687         goto out;
 688 }
 689 EXPORT_SYMBOL(inet_stream_connect);
 690
 691 /*
 692  *      Accept a pending connection. The TCP layer now gives BSD semantics.
 693  */
 694
 695 int inet_accept(struct socket *sock, struct socket *newsock, int flags)
 696 {
 697         struct sock *sk1 = sock->sk;
 698         int err = -EINVAL;
 699         struct sock *sk2 = sk1->sk_prot->accept(sk1, flags, &err);
 700
 701         if (!sk2)
 702                 goto do_err;
 703
 704         lock_sock(sk2);
 705
 706         WARN_ON(!((1 << sk2->sk_state) &
 707                   (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT | TCPF_CLOSE)));
 708
 709         sock_graft(sk2, newsock);
 710
 711         newsock->state = SS_CONNECTED;
 712         err = 0;
 713         release_sock(sk2);
 714 do_err:
 715         return err;
 716 }
 717 EXPORT_SYMBOL(inet_accept);
 718
 719
 720 /*
 721  *      This does both peername and sockname.
 722  */
 723 int inet_getname(struct socket *sock, struct sockaddr *uaddr,
 724                         int *uaddr_len, int peer)
 725 {
 726         struct sock *sk         = sock->sk;
 727         struct inet_sock *inet  = inet_sk(sk);
 728         DECLARE_SOCKADDR(struct sockaddr_in *, sin, uaddr);
 729
 730         sin->sin_family = AF_INET;
 731         if (peer) {
 732                 if (!inet->inet_dport ||
 733                     (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
 734                      peer == 1))
 735                         return -ENOTCONN;
 736                 sin->sin_port = inet->inet_dport;
 737                 sin->sin_addr.s_addr = inet->inet_daddr;
 738         } else {
 739                 __be32 addr = inet->inet_rcv_saddr;
 740                 if (!addr)
 741                         addr = inet->inet_saddr;
 742                 sin->sin_port = inet->inet_sport;
 743                 sin->sin_addr.s_addr = addr;
 744         }
 745         memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
 746         *uaddr_len = sizeof(*sin);
 747         return 0;
 748 }
 749 EXPORT_SYMBOL(inet_getname);
 750
 751 int inet_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
 752                  size_t size)
 753 {
 754         struct sock *sk = sock->sk;
 755
 756         sock_rps_record_flow(sk);
 757
 758         /* We may need to bind the socket. */
 759         if (!inet_sk(sk)->inet_num && !sk->sk_prot->no_autobind &&
 760             inet_autobind(sk))
 761                 return -EAGAIN;
 762
 763         return sk->sk_prot->sendmsg(iocb, sk, msg, size);
 764 }
 765 EXPORT_SYMBOL(inet_sendmsg);
 766
 767 ssize_t inet_sendpage(struct socket *sock, struct page *page, int offset,
 768                       size_t size, int flags)
 769 {
 770         struct sock *sk = sock->sk;
 771
 772         sock_rps_record_flow(sk);
 773
 774         /* We may need to bind the socket. */
 775         if (!inet_sk(sk)->inet_num && !sk->sk_prot->no_autobind &&
 776             inet_autobind(sk))
 777                 return -EAGAIN;
 778
 779         if (sk->sk_prot->sendpage)
 780                 return sk->sk_prot->sendpage(sk, page, offset, size, flags);
 781         return sock_no_sendpage(sock, page, offset, size, flags);
 782 }
 783 EXPORT_SYMBOL(inet_sendpage);
 784
 785 int inet_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
 786                  size_t size, int flags)
 787 {
 788         struct sock *sk = sock->sk;
 789         int addr_len = 0;
 790         int err;
 791
 792         sock_rps_record_flow(sk);
 793
 794         err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT,
 795                                    flags & ~MSG_DONTWAIT, &addr_len);
 796         if (err >= 0)
 797                 msg->msg_namelen = addr_len;
 798         return err;
 799 }
 800 EXPORT_SYMBOL(inet_recvmsg);
 801
 802 int inet_shutdown(struct socket *sock, int how)
 803 {
 804         struct sock *sk = sock->sk;
 805         int err = 0;
 806
 807         /* This should really check to make sure
 808          * the socket is a TCP socket. (WHY AC...)
 809          */
 810         how++; /* maps 0->1 has the advantage of making bit 1 rcvs and
 811                        1->2 bit 2 snds.
 812                        2->3 */
 813         if ((how & ~SHUTDOWN_MASK) || !how)     /* MAXINT->0 */
 814                 return -EINVAL;
 815
 816         lock_sock(sk);
 817         if (sock->state == SS_CONNECTING) {
 818                 if ((1 << sk->sk_state) &
 819                     (TCPF_SYN_SENT | TCPF_SYN_RECV | TCPF_CLOSE))
 820                         sock->state = SS_DISCONNECTING;
 821                 else
 822                         sock->state = SS_CONNECTED;
 823         }
 824
 825         switch (sk->sk_state) {
 826         case TCP_CLOSE:
 827                 err = -ENOTCONN;
 828                 /* Hack to wake up other listeners, who can poll for
 829                    POLLHUP, even on eg. unconnected UDP sockets -- RR */
 830         default:
 831                 sk->sk_shutdown |= how;
 832                 if (sk->sk_prot->shutdown)
 833                         sk->sk_prot->shutdown(sk, how);
 834                 break;
 835
 836         /* Remaining two branches are temporary solution for missing
 837          * close() in multithreaded environment. It is _not_ a good idea,
 838          * but we have no choice until close() is repaired at VFS level.
 839          */
 840         case TCP_LISTEN:
 841                 if (!(how & RCV_SHUTDOWN))
 842                         break;
 843                 /* Fall through */
 844         case TCP_SYN_SENT:
 845                 err = sk->sk_prot->disconnect(sk, O_NONBLOCK);
 846                 sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
 847                 break;
 848         }
 849
 850         /* Wake up anyone sleeping in poll. */
 851         sk->sk_state_change(sk);
 852         release_sock(sk);
 853         return err;
 854 }
 855 EXPORT_SYMBOL(inet_shutdown);
 856
 857 /*
 858  *      ioctl() calls you can issue on an INET socket. Most of these are
 859  *      device configuration and stuff and very rarely used. Some ioctls
 860  *      pass on to the socket itself.
 861  *
 862  *      NOTE: I like the idea of a module for the config stuff. ie ifconfig
 863  *      loads the devconfigure module does its configuring and unloads it.
 864  *      There's a good 20K of config code hanging around the kernel.
 865  */
 866
 867 int inet_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 868 {
 869         struct sock *sk = sock->sk;
 870         int err = 0;
 871         struct net *net = sock_net(sk);
 872
 873         switch (cmd) {
 874         case SIOCGSTAMP:
 875                 err = sock_get_timestamp(sk, (struct timeval __user *)arg);
 876                 break;
 877         case SIOCGSTAMPNS:
 878                 err = sock_get_timestampns(sk, (struct timespec __user *)arg);
 879                 break;
 880         case SIOCADDRT:
 881         case SIOCDELRT:
 882         case SIOCRTMSG:
 883                 err = ip_rt_ioctl(net, cmd, (void __user *)arg);
 884                 break;
 885         case SIOCDARP:
 886         case SIOCGARP:
 887         case SIOCSARP:
 888                 err = arp_ioctl(net, cmd, (void __user *)arg);
 889                 break;
 890         case SIOCGIFADDR:
 891         case SIOCSIFADDR:
 892         case SIOCGIFBRDADDR:
 893         case SIOCSIFBRDADDR:
 894         case SIOCGIFNETMASK:
 895         case SIOCSIFNETMASK:
 896         case SIOCGIFDSTADDR:
 897         case SIOCSIFDSTADDR:
 898         case SIOCSIFPFLAGS:
 899         case SIOCGIFPFLAGS:
 900         case SIOCSIFFLAGS:
 901                 err = devinet_ioctl(net, cmd, (void __user *)arg);
 902                 break;
 903         default:
 904                 if (sk->sk_prot->ioctl)
 905                         err = sk->sk_prot->ioctl(sk, cmd, arg);
 906                 else
 907                         err = -ENOIOCTLCMD;
 908                 break;
 909         }
 910         return err;
 911 }
 912 EXPORT_SYMBOL(inet_ioctl);
 913
 914 const struct proto_ops inet_stream_ops = {
 915         .family            = PF_INET,
 916         .owner             = THIS_MODULE,
 917         .release           = inet_release,
 918         .bind              = inet_bind,
 919         .connect           = inet_stream_connect,
 920         .socketpair        = sock_no_socketpair,
 921         .accept            = inet_accept,
 922         .getname           = inet_getname,
 923         .poll              = tcp_poll,
 924         .ioctl             = inet_ioctl,
 925         .listen            = inet_listen,
 926         .shutdown          = inet_shutdown,
 927         .setsockopt        = sock_common_setsockopt,
 928         .getsockopt        = sock_common_getsockopt,
 929         .sendmsg           = inet_sendmsg,
 930         .recvmsg           = inet_recvmsg,
 931         .mmap              = sock_no_mmap,
 932         .sendpage          = inet_sendpage,
 933         .splice_read       = tcp_splice_read,
 934 #ifdef CONFIG_COMPAT
 935         .compat_setsockopt = compat_sock_common_setsockopt,
 936         .compat_getsockopt = compat_sock_common_getsockopt,
 937 #endif
 938 };
 939 EXPORT_SYMBOL(inet_stream_ops);
 940
 941 const struct proto_ops inet_dgram_ops = {
 942         .family            = PF_INET,
 943         .owner             = THIS_MODULE,
 944         .release           = inet_release,
 945         .bind              = inet_bind,
 946         .connect           = inet_dgram_connect,
 947         .socketpair        = sock_no_socketpair,
 948         .accept            = sock_no_accept,
 949         .getname           = inet_getname,
 950         .poll              = udp_poll,
 951         .ioctl             = inet_ioctl,
 952         .listen            = sock_no_listen,
 953         .shutdown          = inet_shutdown,
 954         .setsockopt        = sock_common_setsockopt,
 955         .getsockopt        = sock_common_getsockopt,
 956         .sendmsg           = inet_sendmsg,
 957         .recvmsg           = inet_recvmsg,
 958         .mmap              = sock_no_mmap,
 959         .sendpage          = inet_sendpage,
 960 #ifdef CONFIG_COMPAT
 961         .compat_setsockopt = compat_sock_common_setsockopt,
 962         .compat_getsockopt = compat_sock_common_getsockopt,
 963 #endif
 964 };
 965 EXPORT_SYMBOL(inet_dgram_ops);
 966
 967 /*
 968  * For SOCK_RAW sockets; should be the same as inet_dgram_ops but without
 969  * udp_poll
 970  */
 971 static const struct proto_ops inet_sockraw_ops = {
 972         .family            = PF_INET,
 973         .owner             = THIS_MODULE,
 974         .release           = inet_release,
 975         .bind              = inet_bind,
 976         .connect           = inet_dgram_connect,
 977         .socketpair        = sock_no_socketpair,
 978         .accept            = sock_no_accept,
 979         .getname           = inet_getname,
 980         .poll              = datagram_poll,
 981         .ioctl             = inet_ioctl,
 982         .listen            = sock_no_listen,
 983         .shutdown          = inet_shutdown,
 984         .setsockopt        = sock_common_setsockopt,
 985         .getsockopt        = sock_common_getsockopt,
 986         .sendmsg           = inet_sendmsg,
 987         .recvmsg           = inet_recvmsg,
 988         .mmap              = sock_no_mmap,
 989         .sendpage          = inet_sendpage,
 990 #ifdef CONFIG_COMPAT
 991         .compat_setsockopt = compat_sock_common_setsockopt,
 992         .compat_getsockopt = compat_sock_common_getsockopt,
 993 #endif
 994 };
 995
 996 static const struct net_proto_family inet_family_ops = {
 997         .family = PF_INET,
 998         .create = inet_create,
 999         .owner  = THIS_MODULE,
1000 };
1001
1002 /* Upon startup we insert all the elements in inetsw_array[] into
1003  * the linked list inetsw.
1004  */
1005 static struct inet_protosw inetsw_array[] =
1006 {
1007         {
1008                 .type =       SOCK_STREAM,
1009                 .protocol =   IPPROTO_TCP,
1010                 .prot =       &tcp_prot,
1011                 .ops =        &inet_stream_ops,
1012                 .no_check =   0,
1013                 .flags =      INET_PROTOSW_PERMANENT |
1014                               INET_PROTOSW_ICSK,
1015         },
1016
1017         {
1018                 .type =       SOCK_DGRAM,
1019                 .protocol =   IPPROTO_UDP,
1020                 .prot =       &udp_prot,
1021                 .ops =        &inet_dgram_ops,
1022                 .no_check =   UDP_CSUM_DEFAULT,
1023                 .flags =      INET_PROTOSW_PERMANENT,
1024        },
1025
1026
1027        {
1028                .type =       SOCK_RAW,
1029                .protocol =   IPPROTO_IP,        /* wild card */
1030                .prot =       &raw_prot,
1031                .ops =        &inet_sockraw_ops,
1032                .no_check =   UDP_CSUM_DEFAULT,
1033                .flags =      INET_PROTOSW_REUSE,
1034        }
1035 };
1036
1037 #define INETSW_ARRAY_LEN ARRAY_SIZE(inetsw_array)
1038
1039 void inet_register_protosw(struct inet_protosw *p)
1040 {
1041         struct list_head *lh;
1042         struct inet_protosw *answer;
1043         int protocol = p->protocol;
1044         struct list_head *last_perm;
1045
1046         spin_lock_bh(&inetsw_lock);
1047
1048         if (p->type >= SOCK_MAX)
1049                 goto out_illegal;
1050
1051         /* If we are trying to override a permanent protocol, bail. */
1052         answer = NULL;
1053         last_perm = &inetsw[p->type];
1054         list_for_each(lh, &inetsw[p->type]) {
1055                 answer = list_entry(lh, struct inet_protosw, list);
1056
1057                 /* Check only the non-wild match. */
1058                 if (INET_PROTOSW_PERMANENT & answer->flags) {
1059                         if (protocol == answer->protocol)
1060                                 break;
1061                         last_perm = lh;
1062                 }
1063
1064                 answer = NULL;
1065         }
1066         if (answer)
1067                 goto out_permanent;
1068
1069         /* Add the new entry after the last permanent entry if any, so that
1070          * the new entry does not override a permanent entry when matched with
1071          * a wild-card protocol. But it is allowed to override any existing
1072          * non-permanent entry.  This means that when we remove this entry, the
1073          * system automatically returns to the old behavior.
1074          */
1075         list_add_rcu(&p->list, last_perm);
1076 out:
1077         spin_unlock_bh(&inetsw_lock);
1078
1079         return;
1080
1081 out_permanent:
1082         printk(KERN_ERR "Attempt to override permanent protocol %d.\n",
1083                protocol);
1084         goto out;
1085
1086 out_illegal:
1087         printk(KERN_ERR
1088                "Ignoring attempt to register invalid socket type %d.\n",
1089                p->type);
1090         goto out;
1091 }
1092 EXPORT_SYMBOL(inet_register_protosw);
1093
1094 void inet_unregister_protosw(struct inet_protosw *p)
1095 {
1096         if (INET_PROTOSW_PERMANENT & p->flags) {
1097                 printk(KERN_ERR
1098                        "Attempt to unregister permanent protocol %d.\n",
1099                        p->protocol);
1100         } else {
1101                 spin_lock_bh(&inetsw_lock);
1102                 list_del_rcu(&p->list);
1103                 spin_unlock_bh(&inetsw_lock);
1104
1105                 synchronize_net();
1106         }
1107 }
1108 EXPORT_SYMBOL(inet_unregister_protosw);
1109
1110 /*
1111  *      Shall we try to damage output packets if routing dev changes?
1112  */
1113
1114 int sysctl_ip_dynaddr __read_mostly;
1115
1116 static int inet_sk_reselect_saddr(struct sock *sk)
1117 {
1118         struct inet_sock *inet = inet_sk(sk);
1119         int err;
1120         struct rtable *rt;
1121         __be32 old_saddr = inet->inet_saddr;
1122         __be32 new_saddr;
1123         __be32 daddr = inet->inet_daddr;
1124
1125         if (inet->opt && inet->opt->srr)
1126                 daddr = inet->opt->faddr;
1127
1128         /* Query new route. */
1129         err = ip_route_connect(&rt, daddr, 0,
1130                                RT_CONN_FLAGS(sk),
1131                                sk->sk_bound_dev_if,
1132                                sk->sk_protocol,
1133                                inet->inet_sport, inet->inet_dport, sk, 0);
1134         if (err)
1135                 return err;
1136
1137         sk_setup_caps(sk, &rt->dst);
1138
1139         new_saddr = rt->rt_src;
1140
1141         if (new_saddr == old_saddr)
1142                 return 0;
1143
1144         if (sysctl_ip_dynaddr > 1) {
1145                 printk(KERN_INFO "%s(): shifting inet->saddr from %pI4 to %pI4\n",
1146                        __func__, &old_saddr, &new_saddr);
1147         }
1148
1149         inet->inet_saddr = inet->inet_rcv_saddr = new_saddr;
1150
1151         /*
1152          * XXX The only one ugly spot where we need to
1153          * XXX really change the sockets identity after
1154          * XXX it has entered the hashes. -DaveM
1155          *
1156          * Besides that, it does not check for connection
1157          * uniqueness. Wait for troubles.
1158          */
1159         __sk_prot_rehash(sk);
1160         return 0;
1161 }
1162
1163 int inet_sk_rebuild_header(struct sock *sk)
1164 {
1165         struct inet_sock *inet = inet_sk(sk);
1166         struct rtable *rt = (struct rtable *)__sk_dst_check(sk, 0);
1167         __be32 daddr;
1168         int err;
1169
1170         /* Route is OK, nothing to do. */
1171         if (rt)
1172                 return 0;
1173
1174         /* Reroute. */
1175         daddr = inet->inet_daddr;
1176         if (inet->opt && inet->opt->srr)
1177                 daddr = inet->opt->faddr;
1178 {
1179         struct flowi fl = {
1180                 .oif = sk->sk_bound_dev_if,
1181                 .mark = sk->sk_mark,
1182                 .nl_u = {
1183                         .ip4_u = {
1184                                 .daddr  = daddr,
1185                                 .saddr  = inet->inet_saddr,
1186                                 .tos    = RT_CONN_FLAGS(sk),
1187                         },
1188                 },
1189                 .proto = sk->sk_protocol,
1190                 .flags = inet_sk_flowi_flags(sk),
1191                 .uli_u = {
1192                         .ports = {
1193                                 .sport = inet->inet_sport,
1194                                 .dport = inet->inet_dport,
1195                         },
1196                 },
1197         };
1198
1199         security_sk_classify_flow(sk, &fl);
1200         err = ip_route_output_flow(sock_net(sk), &rt, &fl, sk, 0);
1201 }
1202         if (!err)
1203                 sk_setup_caps(sk, &rt->dst);
1204         else {
1205                 /* Routing failed... */
1206                 sk->sk_route_caps = 0;
1207                 /*
1208                  * Other protocols have to map its equivalent state to TCP_SYN_SENT.
1209                  * DCCP maps its DCCP_REQUESTING state to TCP_SYN_SENT. -acme
1210                  */
1211                 if (!sysctl_ip_dynaddr ||
1212                     sk->sk_state != TCP_SYN_SENT ||
1213                     (sk->sk_userlocks & SOCK_BINDADDR_LOCK) ||
1214                     (err = inet_sk_reselect_saddr(sk)) != 0)
1215                         sk->sk_err_soft = -err;
1216         }
1217
1218         return err;
1219 }
1220 EXPORT_SYMBOL(inet_sk_rebuild_header);
1221
1222 static int inet_gso_send_check(struct sk_buff *skb)
1223 {
1224         struct iphdr *iph;
1225         const struct net_protocol *ops;
1226         int proto;
1227         int ihl;
1228         int err = -EINVAL;
1229
1230         if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
1231                 goto out;
1232
1233         iph = ip_hdr(skb);
1234         ihl = iph->ihl * 4;
1235         if (ihl < sizeof(*iph))
1236                 goto out;
1237
1238         if (unlikely(!pskb_may_pull(skb, ihl)))
1239                 goto out;
1240
1241         __skb_pull(skb, ihl);
1242         skb_reset_transport_header(skb);
1243         iph = ip_hdr(skb);
1244         proto = iph->protocol & (MAX_INET_PROTOS - 1);
1245         err = -EPROTONOSUPPORT;
1246
1247         rcu_read_lock();
1248         ops = rcu_dereference(inet_protos[proto]);
1249         if (likely(ops && ops->gso_send_check))
1250                 err = ops->gso_send_check(skb);
1251         rcu_read_unlock();
1252
1253 out:
1254         return err;
1255 }
1256
1257 static struct sk_buff *inet_gso_segment(struct sk_buff *skb, int features)
1258 {
1259         struct sk_buff *segs = ERR_PTR(-EINVAL);
1260         struct iphdr *iph;
1261         const struct net_protocol *ops;
1262         int proto;
1263         int ihl;
1264         int id;
1265         unsigned int offset = 0;
1266
1267         if (!(features & NETIF_F_V4_CSUM))
1268                 features &= ~NETIF_F_SG;
1269
1270         if (unlikely(skb_shinfo(skb)->gso_type &
1271                      ~(SKB_GSO_TCPV4 |
1272                        SKB_GSO_UDP |
1273                        SKB_GSO_DODGY |
1274                        SKB_GSO_TCP_ECN |
1275                        0)))
1276                 goto out;
1277
1278         if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
1279                 goto out;
1280
1281         iph = ip_hdr(skb);
1282         ihl = iph->ihl * 4;
1283         if (ihl < sizeof(*iph))
1284                 goto out;
1285
1286         if (unlikely(!pskb_may_pull(skb, ihl)))
1287                 goto out;
1288
1289         __skb_pull(skb, ihl);
1290         skb_reset_transport_header(skb);
1291         iph = ip_hdr(skb);
1292         id = ntohs(iph->id);
1293         proto = iph->protocol & (MAX_INET_PROTOS - 1);
1294         segs = ERR_PTR(-EPROTONOSUPPORT);
1295
1296         rcu_read_lock();
1297         ops = rcu_dereference(inet_protos[proto]);
1298         if (likely(ops && ops->gso_segment))
1299                 segs = ops->gso_segment(skb, features);
1300         rcu_read_unlock();
1301
1302         if (!segs || IS_ERR(segs))
1303                 goto out;
1304
1305         skb = segs;
1306         do {
1307                 iph = ip_hdr(skb);
1308                 if (proto == IPPROTO_UDP) {
1309                         iph->id = htons(id);
1310                         iph->frag_off = htons(offset >> 3);
1311                         if (skb->next != NULL)
1312                                 iph->frag_off |= htons(IP_MF);
1313                         offset += (skb->len - skb->mac_len - iph->ihl * 4);
1314                 } else
1315                         iph->id = htons(id++);
1316                 iph->tot_len = htons(skb->len - skb->mac_len);
1317                 iph->check = 0;
1318                 iph->check = ip_fast_csum(skb_network_header(skb), iph->ihl);
1319         } while ((skb = skb->next));
1320
1321 out:
1322         return segs;
1323 }
1324
1325 static struct sk_buff **inet_gro_receive(struct sk_buff **head,
1326                                          struct sk_buff *skb)
1327 {
1328         const struct net_protocol *ops;
1329         struct sk_buff **pp = NULL;
1330         struct sk_buff *p;
1331         struct iphdr *iph;
1332         unsigned int hlen;
1333         unsigned int off;
1334         unsigned int id;
1335         int flush = 1;
1336         int proto;
1337
1338         off = skb_gro_offset(skb);
1339         hlen = off + sizeof(*iph);
1340         iph = skb_gro_header_fast(skb, off);
1341         if (skb_gro_header_hard(skb, hlen)) {
1342                 iph = skb_gro_header_slow(skb, hlen, off);
1343                 if (unlikely(!iph))
1344                         goto out;
1345         }
1346
1347         proto = iph->protocol & (MAX_INET_PROTOS - 1);
1348
1349         rcu_read_lock();
1350         ops = rcu_dereference(inet_protos[proto]);
1351         if (!ops || !ops->gro_receive)
1352                 goto out_unlock;
1353
1354         if (*(u8 *)iph != 0x45)
1355                 goto out_unlock;
1356
1357         if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1358                 goto out_unlock;
1359
1360         id = ntohl(*(__be32 *)&iph->id);
1361         flush = (u16)((ntohl(*(__be32 *)iph) ^ skb_gro_len(skb)) | (id ^ IP_DF));
1362         id >>= 16;
1363
1364         for (p = *head; p; p = p->next) {
1365                 struct iphdr *iph2;
1366
1367                 if (!NAPI_GRO_CB(p)->same_flow)
1368                         continue;
1369
1370                 iph2 = ip_hdr(p);
1371
1372                 if ((iph->protocol ^ iph2->protocol) |
1373                     (iph->tos ^ iph2->tos) |
1374                     ((__force u32)iph->saddr ^ (__force u32)iph2->saddr) |
1375                     ((__force u32)iph->daddr ^ (__force u32)iph2->daddr)) {
1376                         NAPI_GRO_CB(p)->same_flow = 0;
1377                         continue;
1378                 }
1379
1380                 /* All fields must match except length and checksum. */
1381                 NAPI_GRO_CB(p)->flush |=
1382                         (iph->ttl ^ iph2->ttl) |
1383                         ((u16)(ntohs(iph2->id) + NAPI_GRO_CB(p)->count) ^ id);
1384
1385                 NAPI_GRO_CB(p)->flush |= flush;
1386         }
1387
1388         NAPI_GRO_CB(skb)->flush |= flush;
1389         skb_gro_pull(skb, sizeof(*iph));
1390         skb_set_transport_header(skb, skb_gro_offset(skb));
1391
1392         pp = ops->gro_receive(head, skb);
1393
1394 out_unlock:
1395         rcu_read_unlock();
1396
1397 out:
1398         NAPI_GRO_CB(skb)->flush |= flush;
1399
1400         return pp;
1401 }
1402
1403 static int inet_gro_complete(struct sk_buff *skb)
1404 {
1405         const struct net_protocol *ops;
1406         struct iphdr *iph = ip_hdr(skb);
1407         int proto = iph->protocol & (MAX_INET_PROTOS - 1);
1408         int err = -ENOSYS;
1409         __be16 newlen = htons(skb->len - skb_network_offset(skb));
1410
1411         csum_replace2(&iph->check, iph->tot_len, newlen);
1412         iph->tot_len = newlen;
1413
1414         rcu_read_lock();
1415         ops = rcu_dereference(inet_protos[proto]);
1416         if (WARN_ON(!ops || !ops->gro_complete))
1417                 goto out_unlock;
1418
1419         err = ops->gro_complete(skb);
1420
1421 out_unlock:
1422         rcu_read_unlock();
1423
1424         return err;
1425 }
1426
1427 int inet_ctl_sock_create(struct sock **sk, unsigned short family,
1428                          unsigned short type, unsigned char protocol,
1429                          struct net *net)
1430 {
1431         struct socket *sock;
1432         int rc = sock_create_kern(family, type, protocol, &sock);
1433
1434         if (rc == 0) {
1435                 *sk = sock->sk;
1436                 (*sk)->sk_allocation = GFP_ATOMIC;
1437                 /*
1438                  * Unhash it so that IP input processing does not even see it,
1439                  * we do not wish this socket to see incoming packets.
1440                  */
1441                 (*sk)->sk_prot->unhash(*sk);
1442
1443                 sk_change_net(*sk, net);
1444         }
1445         return rc;
1446 }
1447 EXPORT_SYMBOL_GPL(inet_ctl_sock_create);
1448
1449 unsigned long snmp_fold_field(void __percpu *mib[], int offt)
1450 {
1451         unsigned long res = 0;
1452         int i;
1453
1454         for_each_possible_cpu(i) {
1455                 res += *(((unsigned long *) per_cpu_ptr(mib[0], i)) + offt);
1456                 res += *(((unsigned long *) per_cpu_ptr(mib[1], i)) + offt);
1457         }
1458         return res;
1459 }
1460 EXPORT_SYMBOL_GPL(snmp_fold_field);
1461
1462 #if BITS_PER_LONG==32
1463
1464 u64 snmp_fold_field64(void __percpu *mib[], int offt, size_t syncp_offset)
1465 {
1466         u64 res = 0;
1467         int cpu;
1468
1469         for_each_possible_cpu(cpu) {
1470                 void *bhptr, *userptr;
1471                 struct u64_stats_sync *syncp;
1472                 u64 v_bh, v_user;
1473                 unsigned int start;
1474
1475                 /* first mib used by softirq context, we must use _bh() accessors */
1476                 bhptr = per_cpu_ptr(SNMP_STAT_BHPTR(mib), cpu);
1477                 syncp = (struct u64_stats_sync *)(bhptr + syncp_offset);
1478                 do {
1479                         start = u64_stats_fetch_begin_bh(syncp);
1480                         v_bh = *(((u64 *) bhptr) + offt);
1481                 } while (u64_stats_fetch_retry_bh(syncp, start));
1482
1483                 /* second mib used in USER context */
1484                 userptr = per_cpu_ptr(SNMP_STAT_USRPTR(mib), cpu);
1485                 syncp = (struct u64_stats_sync *)(userptr + syncp_offset);
1486                 do {
1487                         start = u64_stats_fetch_begin(syncp);
1488                         v_user = *(((u64 *) userptr) + offt);
1489                 } while (u64_stats_fetch_retry(syncp, start));
1490
1491                 res += v_bh + v_user;
1492         }
1493         return res;
1494 }
1495 EXPORT_SYMBOL_GPL(snmp_fold_field64);
1496 #endif
1497
1498 int snmp_mib_init(void __percpu *ptr[2], size_t mibsize, size_t align)
1499 {
1500         BUG_ON(ptr == NULL);
1501         ptr[0] = __alloc_percpu(mibsize, align);
1502         if (!ptr[0])
1503                 goto err0;
1504         ptr[1] = __alloc_percpu(mibsize, align);
1505         if (!ptr[1])
1506                 goto err1;
1507         return 0;
1508 err1:
1509         free_percpu(ptr[0]);
1510         ptr[0] = NULL;
1511 err0:
1512         return -ENOMEM;
1513 }
1514 EXPORT_SYMBOL_GPL(snmp_mib_init);
1515
1516 void snmp_mib_free(void __percpu *ptr[2])
1517 {
1518         BUG_ON(ptr == NULL);
1519         free_percpu(ptr[0]);
1520         free_percpu(ptr[1]);
1521         ptr[0] = ptr[1] = NULL;
1522 }
1523 EXPORT_SYMBOL_GPL(snmp_mib_free);
1524
1525 #ifdef CONFIG_IP_MULTICAST
1526 static const struct net_protocol igmp_protocol = {
1527         .handler =      igmp_rcv,
1528         .netns_ok =     1,
1529 };
1530 #endif
1531
1532 static const struct net_protocol tcp_protocol = {
1533         .handler =      tcp_v4_rcv,
1534         .err_handler =  tcp_v4_err,
1535         .gso_send_check = tcp_v4_gso_send_check,
1536         .gso_segment =  tcp_tso_segment,
1537         .gro_receive =  tcp4_gro_receive,
1538         .gro_complete = tcp4_gro_complete,
1539         .no_policy =    1,
1540         .netns_ok =     1,
1541 };
1542
1543 static const struct net_protocol udp_protocol = {
1544         .handler =      udp_rcv,
1545         .err_handler =  udp_err,
1546         .gso_send_check = udp4_ufo_send_check,
1547         .gso_segment = udp4_ufo_fragment,
1548         .no_policy =    1,
1549         .netns_ok =     1,
1550 };
1551
1552 static const struct net_protocol icmp_protocol = {
1553         .handler =      icmp_rcv,
1554         .no_policy =    1,
1555         .netns_ok =     1,
1556 };
1557
1558 static __net_init int ipv4_mib_init_net(struct net *net)
1559 {
1560         if (snmp_mib_init((void __percpu **)net->mib.tcp_statistics,
1561                           sizeof(struct tcp_mib),
1562                           __alignof__(struct tcp_mib)) < 0)
1563                 goto err_tcp_mib;
1564         if (snmp_mib_init((void __percpu **)net->mib.ip_statistics,
1565                           sizeof(struct ipstats_mib),
1566                           __alignof__(struct ipstats_mib)) < 0)
1567                 goto err_ip_mib;
1568         if (snmp_mib_init((void __percpu **)net->mib.net_statistics,
1569                           sizeof(struct linux_mib),
1570                           __alignof__(struct linux_mib)) < 0)
1571                 goto err_net_mib;
1572         if (snmp_mib_init((void __percpu **)net->mib.udp_statistics,
1573                           sizeof(struct udp_mib),
1574                           __alignof__(struct udp_mib)) < 0)
1575                 goto err_udp_mib;
1576         if (snmp_mib_init((void __percpu **)net->mib.udplite_statistics,
1577                           sizeof(struct udp_mib),
1578                           __alignof__(struct udp_mib)) < 0)
1579                 goto err_udplite_mib;
1580         if (snmp_mib_init((void __percpu **)net->mib.icmp_statistics,
1581                           sizeof(struct icmp_mib),
1582                           __alignof__(struct icmp_mib)) < 0)
1583                 goto err_icmp_mib;
1584         if (snmp_mib_init((void __percpu **)net->mib.icmpmsg_statistics,
1585                           sizeof(struct icmpmsg_mib),
1586                           __alignof__(struct icmpmsg_mib)) < 0)
1587                 goto err_icmpmsg_mib;
1588
1589         tcp_mib_init(net);
1590         return 0;
1591
1592 err_icmpmsg_mib:
1593         snmp_mib_free((void __percpu **)net->mib.icmp_statistics);
1594 err_icmp_mib:
1595         snmp_mib_free((void __percpu **)net->mib.udplite_statistics);
1596 err_udplite_mib:
1597         snmp_mib_free((void __percpu **)net->mib.udp_statistics);
1598 err_udp_mib:
1599         snmp_mib_free((void __percpu **)net->mib.net_statistics);
1600 err_net_mib:
1601         snmp_mib_free((void __percpu **)net->mib.ip_statistics);
1602 err_ip_mib:
1603         snmp_mib_free((void __percpu **)net->mib.tcp_statistics);
1604 err_tcp_mib:
1605         return -ENOMEM;
1606 }
1607
1608 static __net_exit void ipv4_mib_exit_net(struct net *net)
1609 {
1610         snmp_mib_free((void __percpu **)net->mib.icmpmsg_statistics);
1611         snmp_mib_free((void __percpu **)net->mib.icmp_statistics);
1612         snmp_mib_free((void __percpu **)net->mib.udplite_statistics);
1613         snmp_mib_free((void __percpu **)net->mib.udp_statistics);
1614         snmp_mib_free((void __percpu **)net->mib.net_statistics);
1615         snmp_mib_free((void __percpu **)net->mib.ip_statistics);
1616         snmp_mib_free((void __percpu **)net->mib.tcp_statistics);
1617 }
1618
1619 static __net_initdata struct pernet_operations ipv4_mib_ops = {
1620         .init = ipv4_mib_init_net,
1621         .exit = ipv4_mib_exit_net,
1622 };
1623
1624 static int __init init_ipv4_mibs(void)
1625 {
1626         return register_pernet_subsys(&ipv4_mib_ops);
1627 }
1628
1629 static int ipv4_proc_init(void);
1630
1631 /*
1632  *      IP protocol layer initialiser
1633  */
1634
1635 static struct packet_type ip_packet_type __read_mostly = {
1636         .type = cpu_to_be16(ETH_P_IP),
1637         .func = ip_rcv,
1638         .gso_send_check = inet_gso_send_check,
1639         .gso_segment = inet_gso_segment,
1640         .gro_receive = inet_gro_receive,
1641         .gro_complete = inet_gro_complete,
1642 };
1643
1644 static int __init inet_init(void)
1645 {
1646         struct sk_buff *dummy_skb;
1647         struct inet_protosw *q;
1648         struct list_head *r;
1649         int rc = -EINVAL;
1650
1651         BUILD_BUG_ON(sizeof(struct inet_skb_parm) > sizeof(dummy_skb->cb));
1652
1653         sysctl_local_reserved_ports = kzalloc(65536 / 8, GFP_KERNEL);
1654         if (!sysctl_local_reserved_ports)
1655                 goto out;
1656
1657         rc = proto_register(&tcp_prot, 1);
1658         if (rc)
1659                 goto out_free_reserved_ports;
1660
1661         rc = proto_register(&udp_prot, 1);
1662         if (rc)
1663                 goto out_unregister_tcp_proto;
1664
1665         rc = proto_register(&raw_prot, 1);
1666         if (rc)
1667                 goto out_unregister_udp_proto;
1668
1669         /*
1670          *      Tell SOCKET that we are alive...
1671          */
1672
1673         (void)sock_register(&inet_family_ops);
1674
1675 #ifdef CONFIG_SYSCTL
1676         ip_static_sysctl_init();
1677 #endif
1678
1679         /*
1680          *      Add all the base protocols.
1681          */
1682
1683         if (inet_add_protocol(&icmp_protocol, IPPROTO_ICMP) < 0)
1684                 printk(KERN_CRIT "inet_init: Cannot add ICMP protocol\n");
1685         if (inet_add_protocol(&udp_protocol, IPPROTO_UDP) < 0)
1686                 printk(KERN_CRIT "inet_init: Cannot add UDP protocol\n");
1687         if (inet_add_protocol(&tcp_protocol, IPPROTO_TCP) < 0)
1688                 printk(KERN_CRIT "inet_init: Cannot add TCP protocol\n");
1689 #ifdef CONFIG_IP_MULTICAST
1690         if (inet_add_protocol(&igmp_protocol, IPPROTO_IGMP) < 0)
1691                 printk(KERN_CRIT "inet_init: Cannot add IGMP protocol\n");
1692 #endif
1693
1694         /* Register the socket-side information for inet_create. */
1695         for (r = &inetsw[0]; r < &inetsw[SOCK_MAX]; ++r)
1696                 INIT_LIST_HEAD(r);
1697
1698         for (q = inetsw_array; q < &inetsw_array[INETSW_ARRAY_LEN]; ++q)
1699                 inet_register_protosw(q);
1700
1701         /*
1702          *      Set the ARP module up
1703          */
1704
1705         arp_init();
1706
1707         /*
1708          *      Set the IP module up
1709          */
1710
1711         ip_init();
1712
1713         tcp_v4_init();
1714
1715         /* Setup TCP slab cache for open requests. */
1716         tcp_init();
1717
1718         /* Setup UDP memory threshold */
1719         udp_init();
1720
1721         /* Add UDP-Lite (RFC 3828) */
1722         udplite4_register();
1723
1724         /*
1725          *      Set the ICMP layer up
1726          */
1727
1728         if (icmp_init() < 0)
1729                 panic("Failed to create the ICMP control socket.\n");
1730
1731         /*
1732          *      Initialise the multicast router
1733          */
1734 #if defined(CONFIG_IP_MROUTE)
1735         if (ip_mr_init())
1736                 printk(KERN_CRIT "inet_init: Cannot init ipv4 mroute\n");
1737 #endif
1738         /*
1739          *      Initialise per-cpu ipv4 mibs
1740          */
1741
1742         if (init_ipv4_mibs())
1743                 printk(KERN_CRIT "inet_init: Cannot init ipv4 mibs\n");
1744
1745         ipv4_proc_init();
1746
1747         ipfrag_init();
1748
1749         dev_add_pack(&ip_packet_type);
1750
1751         rc = 0;
1752 out:
1753         return rc;
1754 out_unregister_udp_proto:
1755         proto_unregister(&udp_prot);
1756 out_unregister_tcp_proto:
1757         proto_unregister(&tcp_prot);
1758 out_free_reserved_ports:
1759         kfree(sysctl_local_reserved_ports);
1760         goto out;
1761 }
1762
1763 fs_initcall(inet_init);
1764
1765 /* ------------------------------------------------------------------------ */
1766
1767 #ifdef CONFIG_PROC_FS
1768 static int __init ipv4_proc_init(void)
1769 {
1770         int rc = 0;
1771
1772         if (raw_proc_init())
1773                 goto out_raw;
1774         if (tcp4_proc_init())
1775                 goto out_tcp;
1776         if (udp4_proc_init())
1777                 goto out_udp;
1778         if (ip_misc_proc_init())
1779                 goto out_misc;
1780 out:
1781         return rc;
1782 out_misc:
1783         udp4_proc_exit();
1784 out_udp:
1785         tcp4_proc_exit();
1786 out_tcp:
1787         raw_proc_exit();
1788 out_raw:
1789         rc = -ENOMEM;
1790         goto out;
1791 }
1792
1793 #else /* CONFIG_PROC_FS */
1794 static int __init ipv4_proc_init(void)
1795 {
1796         return 0;
1797 }
1798 #endif /* CONFIG_PROC_FS */
1799
1800 MODULE_ALIAS_NETPROTO(PF_INET);
1801