net/ipv4/af_inet.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * INET         An implementation of the TCP/IP protocol suite for the LINUX
   4  *              operating system.  INET is implemented using the  BSD Socket
   5  *              interface as the means of communication with the user level.
   6  *
   7  *              PF_INET protocol family socket handler.
   8  *
   9  * Authors:     Ross Biro
  10  *              Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
  11  *              Florian La Roche, <flla@stud.uni-sb.de>
  12  *              Alan Cox, <A.Cox@swansea.ac.uk>
  13  *
  14  * Changes (see also sock.c)
  15  *
  16  *              piggy,
  17  *              Karl Knutson    :       Socket protocol table
  18  *              A.N.Kuznetsov   :       Socket death error in accept().
  19  *              John Richardson :       Fix non blocking error in connect()
  20  *                                      so sockets that fail to connect
  21  *                                      don't return -EINPROGRESS.
  22  *              Alan Cox        :       Asynchronous I/O support
  23  *              Alan Cox        :       Keep correct socket pointer on sock
  24  *                                      structures
  25  *                                      when accept() ed
  26  *              Alan Cox        :       Semantics of SO_LINGER aren't state
  27  *                                      moved to close when you look carefully.
  28  *                                      With this fixed and the accept bug fixed
  29  *                                      some RPC stuff seems happier.
  30  *              Niibe Yutaka    :       4.4BSD style write async I/O
  31  *              Alan Cox,
  32  *              Tony Gale       :       Fixed reuse semantics.
  33  *              Alan Cox        :       bind() shouldn't abort existing but dead
  34  *                                      sockets. Stops FTP netin:.. I hope.
  35  *              Alan Cox        :       bind() works correctly for RAW sockets.
  36  *                                      Note that FreeBSD at least was broken
  37  *                                      in this respect so be careful with
  38  *                                      compatibility tests...
  39  *              Alan Cox        :       routing cache support
  40  *              Alan Cox        :       memzero the socket structure for
  41  *                                      compactness.
  42  *              Matt Day        :       nonblock connect error handler
  43  *              Alan Cox        :       Allow large numbers of pending sockets
  44  *                                      (eg for big web sites), but only if
  45  *                                      specifically application requested.
  46  *              Alan Cox        :       New buffering throughout IP. Used
  47  *                                      dumbly.
  48  *              Alan Cox        :       New buffering now used smartly.
  49  *              Alan Cox        :       BSD rather than common sense
  50  *                                      interpretation of listen.
  51  *              Germano Caronni :       Assorted small races.
  52  *              Alan Cox        :       sendmsg/recvmsg basic support.
  53  *              Alan Cox        :       Only sendmsg/recvmsg now supported.
  54  *              Alan Cox        :       Locked down bind (see security list).
  55  *              Alan Cox        :       Loosened bind a little.
  56  *              Mike McLagan    :       ADD/DEL DLCI Ioctls
  57  *      Willy Konynenberg       :       Transparent proxying support.
  58  *              David S. Miller :       New socket lookup architecture.
  59  *                                      Some other random speedups.
  60  *              Cyrus Durgin    :       Cleaned up file for kmod hacks.
  61  *              Andi Kleen      :       Fix inet_stream_connect TCP race.
  62  */
  63
  64 #define pr_fmt(fmt) "IPv4: " fmt
  65
  66 #include <linux/err.h>
  67 #include <linux/errno.h>
  68 #include <linux/types.h>
  69 #include <linux/socket.h>
  70 #include <linux/in.h>
  71 #include <linux/kernel.h>
  72 #include <linux/kmod.h>
  73 #include <linux/sched.h>
  74 #include <linux/timer.h>
  75 #include <linux/string.h>
  76 #include <linux/sockios.h>
  77 #include <linux/net.h>
  78 #include <linux/capability.h>
  79 #include <linux/fcntl.h>
  80 #include <linux/mm.h>
  81 #include <linux/interrupt.h>
  82 #include <linux/stat.h>
  83 #include <linux/init.h>
  84 #include <linux/poll.h>
  85 #include <linux/netfilter_ipv4.h>
  86 #include <linux/random.h>
  87 #include <linux/slab.h>
  88
  89 #include <linux/uaccess.h>
  90
  91 #include <linux/inet.h>
  92 #include <linux/igmp.h>
  93 #include <linux/inetdevice.h>
  94 #include <linux/netdevice.h>
  95 #include <net/checksum.h>
  96 #include <net/ip.h>
  97 #include <net/protocol.h>
  98 #include <net/arp.h>
  99 #include <net/route.h>
 100 #include <net/ip_fib.h>
 101 #include <net/inet_connection_sock.h>
 102 #include <net/gro.h>
 103 #include <net/tcp.h>
 104 #include <net/udp.h>
 105 #include <net/udplite.h>
 106 #include <net/ping.h>
 107 #include <linux/skbuff.h>
 108 #include <net/sock.h>
 109 #include <net/raw.h>
 110 #include <net/icmp.h>
 111 #include <net/inet_common.h>
 112 #include <net/ip_tunnels.h>
 113 #include <net/xfrm.h>
 114 #include <net/net_namespace.h>
 115 #include <net/secure_seq.h>
 116 #ifdef CONFIG_IP_MROUTE
 117 #include <linux/mroute.h>
 118 #endif
 119 #include <net/l3mdev.h>
 120 #include <net/compat.h>
 121
 122 #include <trace/events/sock.h>
 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 /* 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_final(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(refcount_read(&sk->sk_wmem_alloc));
 153         WARN_ON(sk->sk_wmem_queued);
 154         WARN_ON(sk_forward_alloc_get(sk));
 155
 156         kfree(rcu_dereference_protected(inet->inet_opt, 1));
 157         dst_release(rcu_dereference_protected(sk->sk_dst_cache, 1));
 158         dst_release(rcu_dereference_protected(sk->sk_rx_dst, 1));
 159         sk_refcnt_debug_dec(sk);
 160 }
 161 EXPORT_SYMBOL(inet_sock_destruct);
 162
 163 /*
 164  *      The routines beyond this point handle the behaviour of an AF_INET
 165  *      socket object. Mostly it punts to the subprotocols of IP to do
 166  *      the work.
 167  */
 168
 169 /*
 170  *      Automatically bind an unbound socket.
 171  */
 172
 173 static int inet_autobind(struct sock *sk)
 174 {
 175         struct inet_sock *inet;
 176         /* We may need to bind the socket. */
 177         lock_sock(sk);
 178         inet = inet_sk(sk);
 179         if (!inet->inet_num) {
 180                 if (sk->sk_prot->get_port(sk, 0)) {
 181                         release_sock(sk);
 182                         return -EAGAIN;
 183                 }
 184                 inet->inet_sport = htons(inet->inet_num);
 185         }
 186         release_sock(sk);
 187         return 0;
 188 }
 189
 190 /*
 191  *      Move a socket into listening state.
 192  */
 193 int inet_listen(struct socket *sock, int backlog)
 194 {
 195         struct sock *sk = sock->sk;
 196         unsigned char old_state;
 197         int err, tcp_fastopen;
 198
 199         lock_sock(sk);
 200
 201         err = -EINVAL;
 202         if (sock->state != SS_UNCONNECTED || sock->type != SOCK_STREAM)
 203                 goto out;
 204
 205         old_state = sk->sk_state;
 206         if (!((1 << old_state) & (TCPF_CLOSE | TCPF_LISTEN)))
 207                 goto out;
 208
 209         WRITE_ONCE(sk->sk_max_ack_backlog, backlog);
 210         /* Really, if the socket is already in listen state
 211          * we can only allow the backlog to be adjusted.
 212          */
 213         if (old_state != TCP_LISTEN) {
 214                 /* Enable TFO w/o requiring TCP_FASTOPEN socket option.
 215                  * Note that only TCP sockets (SOCK_STREAM) will reach here.
 216                  * Also fastopen backlog may already been set via the option
 217                  * because the socket was in TCP_LISTEN state previously but
 218                  * was shutdown() rather than close().
 219                  */
 220                 tcp_fastopen = sock_net(sk)->ipv4.sysctl_tcp_fastopen;
 221                 if ((tcp_fastopen & TFO_SERVER_WO_SOCKOPT1) &&
 222                     (tcp_fastopen & TFO_SERVER_ENABLE) &&
 223                     !inet_csk(sk)->icsk_accept_queue.fastopenq.max_qlen) {
 224                         fastopen_queue_tune(sk, backlog);
 225                         tcp_fastopen_init_key_once(sock_net(sk));
 226                 }
 227
 228                 err = inet_csk_listen_start(sk);
 229                 if (err)
 230                         goto out;
 231                 tcp_call_bpf(sk, BPF_SOCK_OPS_TCP_LISTEN_CB, 0, NULL);
 232         }
 233         err = 0;
 234
 235 out:
 236         release_sock(sk);
 237         return err;
 238 }
 239 EXPORT_SYMBOL(inet_listen);
 240
 241 /*
 242  *      Create an inet socket.
 243  */
 244
 245 static int inet_create(struct net *net, struct socket *sock, int protocol,
 246                        int kern)
 247 {
 248         struct sock *sk;
 249         struct inet_protosw *answer;
 250         struct inet_sock *inet;
 251         struct proto *answer_prot;
 252         unsigned char answer_flags;
 253         int try_loading_module = 0;
 254         int err;
 255
 256         if (protocol < 0 || protocol >= IPPROTO_MAX)
 257                 return -EINVAL;
 258
 259         sock->state = SS_UNCONNECTED;
 260
 261         /* Look for the requested type/protocol pair. */
 262 lookup_protocol:
 263         err = -ESOCKTNOSUPPORT;
 264         rcu_read_lock();
 265         list_for_each_entry_rcu(answer, &inetsw[sock->type], list) {
 266
 267                 err = 0;
 268                 /* Check the non-wild match. */
 269                 if (protocol == answer->protocol) {
 270                         if (protocol != IPPROTO_IP)
 271                                 break;
 272                 } else {
 273                         /* Check for the two wild cases. */
 274                         if (IPPROTO_IP == protocol) {
 275                                 protocol = answer->protocol;
 276                                 break;
 277                         }
 278                         if (IPPROTO_IP == answer->protocol)
 279                                 break;
 280                 }
 281                 err = -EPROTONOSUPPORT;
 282         }
 283
 284         if (unlikely(err)) {
 285                 if (try_loading_module < 2) {
 286                         rcu_read_unlock();
 287                         /*
 288                          * Be more specific, e.g. net-pf-2-proto-132-type-1
 289                          * (net-pf-PF_INET-proto-IPPROTO_SCTP-type-SOCK_STREAM)
 290                          */
 291                         if (++try_loading_module == 1)
 292                                 request_module("net-pf-%d-proto-%d-type-%d",
 293                                                PF_INET, protocol, sock->type);
 294                         /*
 295                          * Fall back to generic, e.g. net-pf-2-proto-132
 296                          * (net-pf-PF_INET-proto-IPPROTO_SCTP)
 297                          */
 298                         else
 299                                 request_module("net-pf-%d-proto-%d",
 300                                                PF_INET, protocol);
 301                         goto lookup_protocol;
 302                 } else
 303                         goto out_rcu_unlock;
 304         }
 305
 306         err = -EPERM;
 307         if (sock->type == SOCK_RAW && !kern &&
 308             !ns_capable(net->user_ns, CAP_NET_RAW))
 309                 goto out_rcu_unlock;
 310
 311         sock->ops = answer->ops;
 312         answer_prot = answer->prot;
 313         answer_flags = answer->flags;
 314         rcu_read_unlock();
 315
 316         WARN_ON(!answer_prot->slab);
 317
 318         err = -ENOMEM;
 319         sk = sk_alloc(net, PF_INET, GFP_KERNEL, answer_prot, kern);
 320         if (!sk)
 321                 goto out;
 322
 323         err = 0;
 324         if (INET_PROTOSW_REUSE & answer_flags)
 325                 sk->sk_reuse = SK_CAN_REUSE;
 326
 327         inet = inet_sk(sk);
 328         inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
 329
 330         inet->nodefrag = 0;
 331
 332         if (SOCK_RAW == sock->type) {
 333                 inet->inet_num = protocol;
 334                 if (IPPROTO_RAW == protocol)
 335                         inet->hdrincl = 1;
 336         }
 337
 338         if (net->ipv4.sysctl_ip_no_pmtu_disc)
 339                 inet->pmtudisc = IP_PMTUDISC_DONT;
 340         else
 341                 inet->pmtudisc = IP_PMTUDISC_WANT;
 342
 343         inet->inet_id = 0;
 344
 345         sock_init_data(sock, sk);
 346
 347         sk->sk_destruct    = inet_sock_destruct;
 348         sk->sk_protocol    = protocol;
 349         sk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
 350
 351         inet->uc_ttl    = -1;
 352         inet->mc_loop   = 1;
 353         inet->mc_ttl    = 1;
 354         inet->mc_all    = 1;
 355         inet->mc_index  = 0;
 356         inet->mc_list   = NULL;
 357         inet->rcv_tos   = 0;
 358
 359         sk_refcnt_debug_inc(sk);
 360
 361         if (inet->inet_num) {
 362                 /* It assumes that any protocol which allows
 363                  * the user to assign a number at socket
 364                  * creation time automatically
 365                  * shares.
 366                  */
 367                 inet->inet_sport = htons(inet->inet_num);
 368                 /* Add to protocol hash chains. */
 369                 err = sk->sk_prot->hash(sk);
 370                 if (err) {
 371                         sk_common_release(sk);
 372                         goto out;
 373                 }
 374         }
 375
 376         if (sk->sk_prot->init) {
 377                 err = sk->sk_prot->init(sk);
 378                 if (err) {
 379                         sk_common_release(sk);
 380                         goto out;
 381                 }
 382         }
 383
 384         if (!kern) {
 385                 err = BPF_CGROUP_RUN_PROG_INET_SOCK(sk);
 386                 if (err) {
 387                         sk_common_release(sk);
 388                         goto out;
 389                 }
 390         }
 391 out:
 392         return err;
 393 out_rcu_unlock:
 394         rcu_read_unlock();
 395         goto out;
 396 }
 397
 398
 399 /*
 400  *      The peer socket should always be NULL (or else). When we call this
 401  *      function we are destroying the object and from then on nobody
 402  *      should refer to it.
 403  */
 404 int inet_release(struct socket *sock)
 405 {
 406         struct sock *sk = sock->sk;
 407
 408         if (sk) {
 409                 long timeout;
 410
 411                 if (!sk->sk_kern_sock)
 412                         BPF_CGROUP_RUN_PROG_INET_SOCK_RELEASE(sk);
 413
 414                 /* Applications forget to leave groups before exiting */
 415                 ip_mc_drop_socket(sk);
 416
 417                 /* If linger is set, we don't return until the close
 418                  * is complete.  Otherwise we return immediately. The
 419                  * actually closing is done the same either way.
 420                  *
 421                  * If the close is due to the process exiting, we never
 422                  * linger..
 423                  */
 424                 timeout = 0;
 425                 if (sock_flag(sk, SOCK_LINGER) &&
 426                     !(current->flags & PF_EXITING))
 427                         timeout = sk->sk_lingertime;
 428                 sk->sk_prot->close(sk, timeout);
 429                 sock->sk = NULL;
 430         }
 431         return 0;
 432 }
 433 EXPORT_SYMBOL(inet_release);
 434
 435 int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 436 {
 437         struct sock *sk = sock->sk;
 438         u32 flags = BIND_WITH_LOCK;
 439         int err;
 440
 441         /* If the socket has its own bind function then use it. (RAW) */
 442         if (sk->sk_prot->bind) {
 443                 return sk->sk_prot->bind(sk, uaddr, addr_len);
 444         }
 445         if (addr_len < sizeof(struct sockaddr_in))
 446                 return -EINVAL;
 447
 448         /* BPF prog is run before any checks are done so that if the prog
 449          * changes context in a wrong way it will be caught.
 450          */
 451         err = BPF_CGROUP_RUN_PROG_INET_BIND_LOCK(sk, uaddr,
 452                                                  CGROUP_INET4_BIND, &flags);
 453         if (err)
 454                 return err;
 455
 456         return __inet_bind(sk, uaddr, addr_len, flags);
 457 }
 458 EXPORT_SYMBOL(inet_bind);
 459
 460 int __inet_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len,
 461                 u32 flags)
 462 {
 463         struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
 464         struct inet_sock *inet = inet_sk(sk);
 465         struct net *net = sock_net(sk);
 466         unsigned short snum;
 467         int chk_addr_ret;
 468         u32 tb_id = RT_TABLE_LOCAL;
 469         int err;
 470
 471         if (addr->sin_family != AF_INET) {
 472                 /* Compatibility games : accept AF_UNSPEC (mapped to AF_INET)
 473                  * only if s_addr is INADDR_ANY.
 474                  */
 475                 err = -EAFNOSUPPORT;
 476                 if (addr->sin_family != AF_UNSPEC ||
 477                     addr->sin_addr.s_addr != htonl(INADDR_ANY))
 478                         goto out;
 479         }
 480
 481         tb_id = l3mdev_fib_table_by_index(net, sk->sk_bound_dev_if) ? : tb_id;
 482         chk_addr_ret = inet_addr_type_table(net, addr->sin_addr.s_addr, tb_id);
 483
 484         /* Not specified by any standard per-se, however it breaks too
 485          * many applications when removed.  It is unfortunate since
 486          * allowing applications to make a non-local bind solves
 487          * several problems with systems using dynamic addressing.
 488          * (ie. your servers still start up even if your ISDN link
 489          *  is temporarily down)
 490          */
 491         err = -EADDRNOTAVAIL;
 492         if (!inet_addr_valid_or_nonlocal(net, inet, addr->sin_addr.s_addr,
 493                                          chk_addr_ret))
 494                 goto out;
 495
 496         snum = ntohs(addr->sin_port);
 497         err = -EACCES;
 498         if (!(flags & BIND_NO_CAP_NET_BIND_SERVICE) &&
 499             snum && inet_port_requires_bind_service(net, snum) &&
 500             !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE))
 501                 goto out;
 502
 503         /*      We keep a pair of addresses. rcv_saddr is the one
 504          *      used by hash lookups, and saddr is used for transmit.
 505          *
 506          *      In the BSD API these are the same except where it
 507          *      would be illegal to use them (multicast/broadcast) in
 508          *      which case the sending device address is used.
 509          */
 510         if (flags & BIND_WITH_LOCK)
 511                 lock_sock(sk);
 512
 513         /* Check these errors (active socket, double bind). */
 514         err = -EINVAL;
 515         if (sk->sk_state != TCP_CLOSE || inet->inet_num)
 516                 goto out_release_sock;
 517
 518         inet->inet_rcv_saddr = inet->inet_saddr = addr->sin_addr.s_addr;
 519         if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST)
 520                 inet->inet_saddr = 0;  /* Use device */
 521
 522         /* Make sure we are allowed to bind here. */
 523         if (snum || !(inet->bind_address_no_port ||
 524                       (flags & BIND_FORCE_ADDRESS_NO_PORT))) {
 525                 if (sk->sk_prot->get_port(sk, snum)) {
 526                         inet->inet_saddr = inet->inet_rcv_saddr = 0;
 527                         err = -EADDRINUSE;
 528                         goto out_release_sock;
 529                 }
 530                 if (!(flags & BIND_FROM_BPF)) {
 531                         err = BPF_CGROUP_RUN_PROG_INET4_POST_BIND(sk);
 532                         if (err) {
 533                                 inet->inet_saddr = inet->inet_rcv_saddr = 0;
 534                                 if (sk->sk_prot->put_port)
 535                                         sk->sk_prot->put_port(sk);
 536                                 goto out_release_sock;
 537                         }
 538                 }
 539         }
 540
 541         if (inet->inet_rcv_saddr)
 542                 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
 543         if (snum)
 544                 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
 545         inet->inet_sport = htons(inet->inet_num);
 546         inet->inet_daddr = 0;
 547         inet->inet_dport = 0;
 548         sk_dst_reset(sk);
 549         err = 0;
 550 out_release_sock:
 551         if (flags & BIND_WITH_LOCK)
 552                 release_sock(sk);
 553 out:
 554         return err;
 555 }
 556
 557 int inet_dgram_connect(struct socket *sock, struct sockaddr *uaddr,
 558                        int addr_len, int flags)
 559 {
 560         struct sock *sk = sock->sk;
 561         int err;
 562
 563         if (addr_len < sizeof(uaddr->sa_family))
 564                 return -EINVAL;
 565         if (uaddr->sa_family == AF_UNSPEC)
 566                 return sk->sk_prot->disconnect(sk, flags);
 567
 568         if (BPF_CGROUP_PRE_CONNECT_ENABLED(sk)) {
 569                 err = sk->sk_prot->pre_connect(sk, uaddr, addr_len);
 570                 if (err)
 571                         return err;
 572         }
 573
 574         if (data_race(!inet_sk(sk)->inet_num) && inet_autobind(sk))
 575                 return -EAGAIN;
 576         return sk->sk_prot->connect(sk, uaddr, addr_len);
 577 }
 578 EXPORT_SYMBOL(inet_dgram_connect);
 579
 580 static long inet_wait_for_connect(struct sock *sk, long timeo, int writebias)
 581 {
 582         DEFINE_WAIT_FUNC(wait, woken_wake_function);
 583
 584         add_wait_queue(sk_sleep(sk), &wait);
 585         sk->sk_write_pending += writebias;
 586
 587         /* Basic assumption: if someone sets sk->sk_err, he _must_
 588          * change state of the socket from TCP_SYN_*.
 589          * Connect() does not allow to get error notifications
 590          * without closing the socket.
 591          */
 592         while ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
 593                 release_sock(sk);
 594                 timeo = wait_woken(&wait, TASK_INTERRUPTIBLE, timeo);
 595                 lock_sock(sk);
 596                 if (signal_pending(current) || !timeo)
 597                         break;
 598         }
 599         remove_wait_queue(sk_sleep(sk), &wait);
 600         sk->sk_write_pending -= writebias;
 601         return timeo;
 602 }
 603
 604 /*
 605  *      Connect to a remote host. There is regrettably still a little
 606  *      TCP 'magic' in here.
 607  */
 608 int __inet_stream_connect(struct socket *sock, struct sockaddr *uaddr,
 609                           int addr_len, int flags, int is_sendmsg)
 610 {
 611         struct sock *sk = sock->sk;
 612         int err;
 613         long timeo;
 614
 615         /*
 616          * uaddr can be NULL and addr_len can be 0 if:
 617          * sk is a TCP fastopen active socket and
 618          * TCP_FASTOPEN_CONNECT sockopt is set and
 619          * we already have a valid cookie for this socket.
 620          * In this case, user can call write() after connect().
 621          * write() will invoke tcp_sendmsg_fastopen() which calls
 622          * __inet_stream_connect().
 623          */
 624         if (uaddr) {
 625                 if (addr_len < sizeof(uaddr->sa_family))
 626                         return -EINVAL;
 627
 628                 if (uaddr->sa_family == AF_UNSPEC) {
 629                         err = sk->sk_prot->disconnect(sk, flags);
 630                         sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
 631                         goto out;
 632                 }
 633         }
 634
 635         switch (sock->state) {
 636         default:
 637                 err = -EINVAL;
 638                 goto out;
 639         case SS_CONNECTED:
 640                 err = -EISCONN;
 641                 goto out;
 642         case SS_CONNECTING:
 643                 if (inet_sk(sk)->defer_connect)
 644                         err = is_sendmsg ? -EINPROGRESS : -EISCONN;
 645                 else
 646                         err = -EALREADY;
 647                 /* Fall out of switch with err, set for this state */
 648                 break;
 649         case SS_UNCONNECTED:
 650                 err = -EISCONN;
 651                 if (sk->sk_state != TCP_CLOSE)
 652                         goto out;
 653
 654                 if (BPF_CGROUP_PRE_CONNECT_ENABLED(sk)) {
 655                         err = sk->sk_prot->pre_connect(sk, uaddr, addr_len);
 656                         if (err)
 657                                 goto out;
 658                 }
 659
 660                 err = sk->sk_prot->connect(sk, uaddr, addr_len);
 661                 if (err < 0)
 662                         goto out;
 663
 664                 sock->state = SS_CONNECTING;
 665
 666                 if (!err && inet_sk(sk)->defer_connect)
 667                         goto out;
 668
 669                 /* Just entered SS_CONNECTING state; the only
 670                  * difference is that return value in non-blocking
 671                  * case is EINPROGRESS, rather than EALREADY.
 672                  */
 673                 err = -EINPROGRESS;
 674                 break;
 675         }
 676
 677         timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
 678
 679         if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
 680                 int writebias = (sk->sk_protocol == IPPROTO_TCP) &&
 681                                 tcp_sk(sk)->fastopen_req &&
 682                                 tcp_sk(sk)->fastopen_req->data ? 1 : 0;
 683
 684                 /* Error code is set above */
 685                 if (!timeo || !inet_wait_for_connect(sk, timeo, writebias))
 686                         goto out;
 687
 688                 err = sock_intr_errno(timeo);
 689                 if (signal_pending(current))
 690                         goto out;
 691         }
 692
 693         /* Connection was closed by RST, timeout, ICMP error
 694          * or another process disconnected us.
 695          */
 696         if (sk->sk_state == TCP_CLOSE)
 697                 goto sock_error;
 698
 699         /* sk->sk_err may be not zero now, if RECVERR was ordered by user
 700          * and error was received after socket entered established state.
 701          * Hence, it is handled normally after connect() return successfully.
 702          */
 703
 704         sock->state = SS_CONNECTED;
 705         err = 0;
 706 out:
 707         return err;
 708
 709 sock_error:
 710         err = sock_error(sk) ? : -ECONNABORTED;
 711         sock->state = SS_UNCONNECTED;
 712         if (sk->sk_prot->disconnect(sk, flags))
 713                 sock->state = SS_DISCONNECTING;
 714         goto out;
 715 }
 716 EXPORT_SYMBOL(__inet_stream_connect);
 717
 718 int inet_stream_connect(struct socket *sock, struct sockaddr *uaddr,
 719                         int addr_len, int flags)
 720 {
 721         int err;
 722
 723         lock_sock(sock->sk);
 724         err = __inet_stream_connect(sock, uaddr, addr_len, flags, 0);
 725         release_sock(sock->sk);
 726         return err;
 727 }
 728 EXPORT_SYMBOL(inet_stream_connect);
 729
 730 /*
 731  *      Accept a pending connection. The TCP layer now gives BSD semantics.
 732  */
 733
 734 int inet_accept(struct socket *sock, struct socket *newsock, int flags,
 735                 bool kern)
 736 {
 737         struct sock *sk1 = sock->sk;
 738         int err = -EINVAL;
 739         struct sock *sk2 = sk1->sk_prot->accept(sk1, flags, &err, kern);
 740
 741         if (!sk2)
 742                 goto do_err;
 743
 744         lock_sock(sk2);
 745
 746         sock_rps_record_flow(sk2);
 747         WARN_ON(!((1 << sk2->sk_state) &
 748                   (TCPF_ESTABLISHED | TCPF_SYN_RECV |
 749                   TCPF_CLOSE_WAIT | TCPF_CLOSE)));
 750
 751         sock_graft(sk2, newsock);
 752
 753         newsock->state = SS_CONNECTED;
 754         err = 0;
 755         release_sock(sk2);
 756 do_err:
 757         return err;
 758 }
 759 EXPORT_SYMBOL(inet_accept);
 760
 761 /*
 762  *      This does both peername and sockname.
 763  */
 764 int inet_getname(struct socket *sock, struct sockaddr *uaddr,
 765                  int peer)
 766 {
 767         struct sock *sk         = sock->sk;
 768         struct inet_sock *inet  = inet_sk(sk);
 769         DECLARE_SOCKADDR(struct sockaddr_in *, sin, uaddr);
 770
 771         sin->sin_family = AF_INET;
 772         lock_sock(sk);
 773         if (peer) {
 774                 if (!inet->inet_dport ||
 775                     (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
 776                      peer == 1)) {
 777                         release_sock(sk);
 778                         return -ENOTCONN;
 779                 }
 780                 sin->sin_port = inet->inet_dport;
 781                 sin->sin_addr.s_addr = inet->inet_daddr;
 782                 BPF_CGROUP_RUN_SA_PROG(sk, (struct sockaddr *)sin,
 783                                        CGROUP_INET4_GETPEERNAME);
 784         } else {
 785                 __be32 addr = inet->inet_rcv_saddr;
 786                 if (!addr)
 787                         addr = inet->inet_saddr;
 788                 sin->sin_port = inet->inet_sport;
 789                 sin->sin_addr.s_addr = addr;
 790                 BPF_CGROUP_RUN_SA_PROG(sk, (struct sockaddr *)sin,
 791                                        CGROUP_INET4_GETSOCKNAME);
 792         }
 793         release_sock(sk);
 794         memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
 795         return sizeof(*sin);
 796 }
 797 EXPORT_SYMBOL(inet_getname);
 798
 799 int inet_send_prepare(struct sock *sk)
 800 {
 801         sock_rps_record_flow(sk);
 802
 803         /* We may need to bind the socket. */
 804         if (data_race(!inet_sk(sk)->inet_num) && !sk->sk_prot->no_autobind &&
 805             inet_autobind(sk))
 806                 return -EAGAIN;
 807
 808         return 0;
 809 }
 810 EXPORT_SYMBOL_GPL(inet_send_prepare);
 811
 812 int inet_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
 813 {
 814         struct sock *sk = sock->sk;
 815
 816         if (unlikely(inet_send_prepare(sk)))
 817                 return -EAGAIN;
 818
 819         return INDIRECT_CALL_2(sk->sk_prot->sendmsg, tcp_sendmsg, udp_sendmsg,
 820                                sk, msg, size);
 821 }
 822 EXPORT_SYMBOL(inet_sendmsg);
 823
 824 ssize_t inet_sendpage(struct socket *sock, struct page *page, int offset,
 825                       size_t size, int flags)
 826 {
 827         struct sock *sk = sock->sk;
 828
 829         if (unlikely(inet_send_prepare(sk)))
 830                 return -EAGAIN;
 831
 832         if (sk->sk_prot->sendpage)
 833                 return sk->sk_prot->sendpage(sk, page, offset, size, flags);
 834         return sock_no_sendpage(sock, page, offset, size, flags);
 835 }
 836 EXPORT_SYMBOL(inet_sendpage);
 837
 838 INDIRECT_CALLABLE_DECLARE(int udp_recvmsg(struct sock *, struct msghdr *,
 839                                           size_t, int, int, int *));
 840 int inet_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
 841                  int flags)
 842 {
 843         struct sock *sk = sock->sk;
 844         int addr_len = 0;
 845         int err;
 846
 847         if (likely(!(flags & MSG_ERRQUEUE)))
 848                 sock_rps_record_flow(sk);
 849
 850         err = INDIRECT_CALL_2(sk->sk_prot->recvmsg, tcp_recvmsg, udp_recvmsg,
 851                               sk, msg, size, flags & MSG_DONTWAIT,
 852                               flags & ~MSG_DONTWAIT, &addr_len);
 853         if (err >= 0)
 854                 msg->msg_namelen = addr_len;
 855         return err;
 856 }
 857 EXPORT_SYMBOL(inet_recvmsg);
 858
 859 int inet_shutdown(struct socket *sock, int how)
 860 {
 861         struct sock *sk = sock->sk;
 862         int err = 0;
 863
 864         /* This should really check to make sure
 865          * the socket is a TCP socket. (WHY AC...)
 866          */
 867         how++; /* maps 0->1 has the advantage of making bit 1 rcvs and
 868                        1->2 bit 2 snds.
 869                        2->3 */
 870         if ((how & ~SHUTDOWN_MASK) || !how)     /* MAXINT->0 */
 871                 return -EINVAL;
 872
 873         lock_sock(sk);
 874         if (sock->state == SS_CONNECTING) {
 875                 if ((1 << sk->sk_state) &
 876                     (TCPF_SYN_SENT | TCPF_SYN_RECV | TCPF_CLOSE))
 877                         sock->state = SS_DISCONNECTING;
 878                 else
 879                         sock->state = SS_CONNECTED;
 880         }
 881
 882         switch (sk->sk_state) {
 883         case TCP_CLOSE:
 884                 err = -ENOTCONN;
 885                 /* Hack to wake up other listeners, who can poll for
 886                    EPOLLHUP, even on eg. unconnected UDP sockets -- RR */
 887                 fallthrough;
 888         default:
 889                 sk->sk_shutdown |= how;
 890                 if (sk->sk_prot->shutdown)
 891                         sk->sk_prot->shutdown(sk, how);
 892                 break;
 893
 894         /* Remaining two branches are temporary solution for missing
 895          * close() in multithreaded environment. It is _not_ a good idea,
 896          * but we have no choice until close() is repaired at VFS level.
 897          */
 898         case TCP_LISTEN:
 899                 if (!(how & RCV_SHUTDOWN))
 900                         break;
 901                 fallthrough;
 902         case TCP_SYN_SENT:
 903                 err = sk->sk_prot->disconnect(sk, O_NONBLOCK);
 904                 sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
 905                 break;
 906         }
 907
 908         /* Wake up anyone sleeping in poll. */
 909         sk->sk_state_change(sk);
 910         release_sock(sk);
 911         return err;
 912 }
 913 EXPORT_SYMBOL(inet_shutdown);
 914
 915 /*
 916  *      ioctl() calls you can issue on an INET socket. Most of these are
 917  *      device configuration and stuff and very rarely used. Some ioctls
 918  *      pass on to the socket itself.
 919  *
 920  *      NOTE: I like the idea of a module for the config stuff. ie ifconfig
 921  *      loads the devconfigure module does its configuring and unloads it.
 922  *      There's a good 20K of config code hanging around the kernel.
 923  */
 924
 925 int inet_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 926 {
 927         struct sock *sk = sock->sk;
 928         int err = 0;
 929         struct net *net = sock_net(sk);
 930         void __user *p = (void __user *)arg;
 931         struct ifreq ifr;
 932         struct rtentry rt;
 933
 934         switch (cmd) {
 935         case SIOCADDRT:
 936         case SIOCDELRT:
 937                 if (copy_from_user(&rt, p, sizeof(struct rtentry)))
 938                         return -EFAULT;
 939                 err = ip_rt_ioctl(net, cmd, &rt);
 940                 break;
 941         case SIOCRTMSG:
 942                 err = -EINVAL;
 943                 break;
 944         case SIOCDARP:
 945         case SIOCGARP:
 946         case SIOCSARP:
 947                 err = arp_ioctl(net, cmd, (void __user *)arg);
 948                 break;
 949         case SIOCGIFADDR:
 950         case SIOCGIFBRDADDR:
 951         case SIOCGIFNETMASK:
 952         case SIOCGIFDSTADDR:
 953         case SIOCGIFPFLAGS:
 954                 if (get_user_ifreq(&ifr, NULL, p))
 955                         return -EFAULT;
 956                 err = devinet_ioctl(net, cmd, &ifr);
 957                 if (!err && put_user_ifreq(&ifr, p))
 958                         err = -EFAULT;
 959                 break;
 960
 961         case SIOCSIFADDR:
 962         case SIOCSIFBRDADDR:
 963         case SIOCSIFNETMASK:
 964         case SIOCSIFDSTADDR:
 965         case SIOCSIFPFLAGS:
 966         case SIOCSIFFLAGS:
 967                 if (get_user_ifreq(&ifr, NULL, p))
 968                         return -EFAULT;
 969                 err = devinet_ioctl(net, cmd, &ifr);
 970                 break;
 971         default:
 972                 if (sk->sk_prot->ioctl)
 973                         err = sk->sk_prot->ioctl(sk, cmd, arg);
 974                 else
 975                         err = -ENOIOCTLCMD;
 976                 break;
 977         }
 978         return err;
 979 }
 980 EXPORT_SYMBOL(inet_ioctl);
 981
 982 #ifdef CONFIG_COMPAT
 983 static int inet_compat_routing_ioctl(struct sock *sk, unsigned int cmd,
 984                 struct compat_rtentry __user *ur)
 985 {
 986         compat_uptr_t rtdev;
 987         struct rtentry rt;
 988
 989         if (copy_from_user(&rt.rt_dst, &ur->rt_dst,
 990                         3 * sizeof(struct sockaddr)) ||
 991             get_user(rt.rt_flags, &ur->rt_flags) ||
 992             get_user(rt.rt_metric, &ur->rt_metric) ||
 993             get_user(rt.rt_mtu, &ur->rt_mtu) ||
 994             get_user(rt.rt_window, &ur->rt_window) ||
 995             get_user(rt.rt_irtt, &ur->rt_irtt) ||
 996             get_user(rtdev, &ur->rt_dev))
 997                 return -EFAULT;
 998
 999         rt.rt_dev = compat_ptr(rtdev);
1000         return ip_rt_ioctl(sock_net(sk), cmd, &rt);
1001 }
1002
1003 static int inet_compat_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1004 {
1005         void __user *argp = compat_ptr(arg);
1006         struct sock *sk = sock->sk;
1007
1008         switch (cmd) {
1009         case SIOCADDRT:
1010         case SIOCDELRT:
1011                 return inet_compat_routing_ioctl(sk, cmd, argp);
1012         default:
1013                 if (!sk->sk_prot->compat_ioctl)
1014                         return -ENOIOCTLCMD;
1015                 return sk->sk_prot->compat_ioctl(sk, cmd, arg);
1016         }
1017 }
1018 #endif /* CONFIG_COMPAT */
1019
1020 const struct proto_ops inet_stream_ops = {
1021         .family            = PF_INET,
1022         .owner             = THIS_MODULE,
1023         .release           = inet_release,
1024         .bind              = inet_bind,
1025         .connect           = inet_stream_connect,
1026         .socketpair        = sock_no_socketpair,
1027         .accept            = inet_accept,
1028         .getname           = inet_getname,
1029         .poll              = tcp_poll,
1030         .ioctl             = inet_ioctl,
1031         .gettstamp         = sock_gettstamp,
1032         .listen            = inet_listen,
1033         .shutdown          = inet_shutdown,
1034         .setsockopt        = sock_common_setsockopt,
1035         .getsockopt        = sock_common_getsockopt,
1036         .sendmsg           = inet_sendmsg,
1037         .recvmsg           = inet_recvmsg,
1038 #ifdef CONFIG_MMU
1039         .mmap              = tcp_mmap,
1040 #endif
1041         .sendpage          = inet_sendpage,
1042         .splice_read       = tcp_splice_read,
1043         .read_sock         = tcp_read_sock,
1044         .sendmsg_locked    = tcp_sendmsg_locked,
1045         .sendpage_locked   = tcp_sendpage_locked,
1046         .peek_len          = tcp_peek_len,
1047 #ifdef CONFIG_COMPAT
1048         .compat_ioctl      = inet_compat_ioctl,
1049 #endif
1050         .set_rcvlowat      = tcp_set_rcvlowat,
1051 };
1052 EXPORT_SYMBOL(inet_stream_ops);
1053
1054 const struct proto_ops inet_dgram_ops = {
1055         .family            = PF_INET,
1056         .owner             = THIS_MODULE,
1057         .release           = inet_release,
1058         .bind              = inet_bind,
1059         .connect           = inet_dgram_connect,
1060         .socketpair        = sock_no_socketpair,
1061         .accept            = sock_no_accept,
1062         .getname           = inet_getname,
1063         .poll              = udp_poll,
1064         .ioctl             = inet_ioctl,
1065         .gettstamp         = sock_gettstamp,
1066         .listen            = sock_no_listen,
1067         .shutdown          = inet_shutdown,
1068         .setsockopt        = sock_common_setsockopt,
1069         .getsockopt        = sock_common_getsockopt,
1070         .sendmsg           = inet_sendmsg,
1071         .read_sock         = udp_read_sock,
1072         .recvmsg           = inet_recvmsg,
1073         .mmap              = sock_no_mmap,
1074         .sendpage          = inet_sendpage,
1075         .set_peek_off      = sk_set_peek_off,
1076 #ifdef CONFIG_COMPAT
1077         .compat_ioctl      = inet_compat_ioctl,
1078 #endif
1079 };
1080 EXPORT_SYMBOL(inet_dgram_ops);
1081
1082 /*
1083  * For SOCK_RAW sockets; should be the same as inet_dgram_ops but without
1084  * udp_poll
1085  */
1086 static const struct proto_ops inet_sockraw_ops = {
1087         .family            = PF_INET,
1088         .owner             = THIS_MODULE,
1089         .release           = inet_release,
1090         .bind              = inet_bind,
1091         .connect           = inet_dgram_connect,
1092         .socketpair        = sock_no_socketpair,
1093         .accept            = sock_no_accept,
1094         .getname           = inet_getname,
1095         .poll              = datagram_poll,
1096         .ioctl             = inet_ioctl,
1097         .gettstamp         = sock_gettstamp,
1098         .listen            = sock_no_listen,
1099         .shutdown          = inet_shutdown,
1100         .setsockopt        = sock_common_setsockopt,
1101         .getsockopt        = sock_common_getsockopt,
1102         .sendmsg           = inet_sendmsg,
1103         .recvmsg           = inet_recvmsg,
1104         .mmap              = sock_no_mmap,
1105         .sendpage          = inet_sendpage,
1106 #ifdef CONFIG_COMPAT
1107         .compat_ioctl      = inet_compat_ioctl,
1108 #endif
1109 };
1110
1111 static const struct net_proto_family inet_family_ops = {
1112         .family = PF_INET,
1113         .create = inet_create,
1114         .owner  = THIS_MODULE,
1115 };
1116
1117 /* Upon startup we insert all the elements in inetsw_array[] into
1118  * the linked list inetsw.
1119  */
1120 static struct inet_protosw inetsw_array[] =
1121 {
1122         {
1123                 .type =       SOCK_STREAM,
1124                 .protocol =   IPPROTO_TCP,
1125                 .prot =       &tcp_prot,
1126                 .ops =        &inet_stream_ops,
1127                 .flags =      INET_PROTOSW_PERMANENT |
1128                               INET_PROTOSW_ICSK,
1129         },
1130
1131         {
1132                 .type =       SOCK_DGRAM,
1133                 .protocol =   IPPROTO_UDP,
1134                 .prot =       &udp_prot,
1135                 .ops =        &inet_dgram_ops,
1136                 .flags =      INET_PROTOSW_PERMANENT,
1137        },
1138
1139        {
1140                 .type =       SOCK_DGRAM,
1141                 .protocol =   IPPROTO_ICMP,
1142                 .prot =       &ping_prot,
1143                 .ops =        &inet_sockraw_ops,
1144                 .flags =      INET_PROTOSW_REUSE,
1145        },
1146
1147        {
1148                .type =       SOCK_RAW,
1149                .protocol =   IPPROTO_IP,        /* wild card */
1150                .prot =       &raw_prot,
1151                .ops =        &inet_sockraw_ops,
1152                .flags =      INET_PROTOSW_REUSE,
1153        }
1154 };
1155
1156 #define INETSW_ARRAY_LEN ARRAY_SIZE(inetsw_array)
1157
1158 void inet_register_protosw(struct inet_protosw *p)
1159 {
1160         struct list_head *lh;
1161         struct inet_protosw *answer;
1162         int protocol = p->protocol;
1163         struct list_head *last_perm;
1164
1165         spin_lock_bh(&inetsw_lock);
1166
1167         if (p->type >= SOCK_MAX)
1168                 goto out_illegal;
1169
1170         /* If we are trying to override a permanent protocol, bail. */
1171         last_perm = &inetsw[p->type];
1172         list_for_each(lh, &inetsw[p->type]) {
1173                 answer = list_entry(lh, struct inet_protosw, list);
1174                 /* Check only the non-wild match. */
1175                 if ((INET_PROTOSW_PERMANENT & answer->flags) == 0)
1176                         break;
1177                 if (protocol == answer->protocol)
1178                         goto out_permanent;
1179                 last_perm = lh;
1180         }
1181
1182         /* Add the new entry after the last permanent entry if any, so that
1183          * the new entry does not override a permanent entry when matched with
1184          * a wild-card protocol. But it is allowed to override any existing
1185          * non-permanent entry.  This means that when we remove this entry, the
1186          * system automatically returns to the old behavior.
1187          */
1188         list_add_rcu(&p->list, last_perm);
1189 out:
1190         spin_unlock_bh(&inetsw_lock);
1191
1192         return;
1193
1194 out_permanent:
1195         pr_err("Attempt to override permanent protocol %d\n", protocol);
1196         goto out;
1197
1198 out_illegal:
1199         pr_err("Ignoring attempt to register invalid socket type %d\n",
1200                p->type);
1201         goto out;
1202 }
1203 EXPORT_SYMBOL(inet_register_protosw);
1204
1205 void inet_unregister_protosw(struct inet_protosw *p)
1206 {
1207         if (INET_PROTOSW_PERMANENT & p->flags) {
1208                 pr_err("Attempt to unregister permanent protocol %d\n",
1209                        p->protocol);
1210         } else {
1211                 spin_lock_bh(&inetsw_lock);
1212                 list_del_rcu(&p->list);
1213                 spin_unlock_bh(&inetsw_lock);
1214
1215                 synchronize_net();
1216         }
1217 }
1218 EXPORT_SYMBOL(inet_unregister_protosw);
1219
1220 static int inet_sk_reselect_saddr(struct sock *sk)
1221 {
1222         struct inet_sock *inet = inet_sk(sk);
1223         __be32 old_saddr = inet->inet_saddr;
1224         __be32 daddr = inet->inet_daddr;
1225         struct flowi4 *fl4;
1226         struct rtable *rt;
1227         __be32 new_saddr;
1228         struct ip_options_rcu *inet_opt;
1229
1230         inet_opt = rcu_dereference_protected(inet->inet_opt,
1231                                              lockdep_sock_is_held(sk));
1232         if (inet_opt && inet_opt->opt.srr)
1233                 daddr = inet_opt->opt.faddr;
1234
1235         /* Query new route. */
1236         fl4 = &inet->cork.fl.u.ip4;
1237         rt = ip_route_connect(fl4, daddr, 0, RT_CONN_FLAGS(sk),
1238                               sk->sk_bound_dev_if, sk->sk_protocol,
1239                               inet->inet_sport, inet->inet_dport, sk);
1240         if (IS_ERR(rt))
1241                 return PTR_ERR(rt);
1242
1243         sk_setup_caps(sk, &rt->dst);
1244
1245         new_saddr = fl4->saddr;
1246
1247         if (new_saddr == old_saddr)
1248                 return 0;
1249
1250         if (sock_net(sk)->ipv4.sysctl_ip_dynaddr > 1) {
1251                 pr_info("%s(): shifting inet->saddr from %pI4 to %pI4\n",
1252                         __func__, &old_saddr, &new_saddr);
1253         }
1254
1255         inet->inet_saddr = inet->inet_rcv_saddr = new_saddr;
1256
1257         /*
1258          * XXX The only one ugly spot where we need to
1259          * XXX really change the sockets identity after
1260          * XXX it has entered the hashes. -DaveM
1261          *
1262          * Besides that, it does not check for connection
1263          * uniqueness. Wait for troubles.
1264          */
1265         return __sk_prot_rehash(sk);
1266 }
1267
1268 int inet_sk_rebuild_header(struct sock *sk)
1269 {
1270         struct inet_sock *inet = inet_sk(sk);
1271         struct rtable *rt = (struct rtable *)__sk_dst_check(sk, 0);
1272         __be32 daddr;
1273         struct ip_options_rcu *inet_opt;
1274         struct flowi4 *fl4;
1275         int err;
1276
1277         /* Route is OK, nothing to do. */
1278         if (rt)
1279                 return 0;
1280
1281         /* Reroute. */
1282         rcu_read_lock();
1283         inet_opt = rcu_dereference(inet->inet_opt);
1284         daddr = inet->inet_daddr;
1285         if (inet_opt && inet_opt->opt.srr)
1286                 daddr = inet_opt->opt.faddr;
1287         rcu_read_unlock();
1288         fl4 = &inet->cork.fl.u.ip4;
1289         rt = ip_route_output_ports(sock_net(sk), fl4, sk, daddr, inet->inet_saddr,
1290                                    inet->inet_dport, inet->inet_sport,
1291                                    sk->sk_protocol, RT_CONN_FLAGS(sk),
1292                                    sk->sk_bound_dev_if);
1293         if (!IS_ERR(rt)) {
1294                 err = 0;
1295                 sk_setup_caps(sk, &rt->dst);
1296         } else {
1297                 err = PTR_ERR(rt);
1298
1299                 /* Routing failed... */
1300                 sk->sk_route_caps = 0;
1301                 /*
1302                  * Other protocols have to map its equivalent state to TCP_SYN_SENT.
1303                  * DCCP maps its DCCP_REQUESTING state to TCP_SYN_SENT. -acme
1304                  */
1305                 if (!sock_net(sk)->ipv4.sysctl_ip_dynaddr ||
1306                     sk->sk_state != TCP_SYN_SENT ||
1307                     (sk->sk_userlocks & SOCK_BINDADDR_LOCK) ||
1308                     (err = inet_sk_reselect_saddr(sk)) != 0)
1309                         sk->sk_err_soft = -err;
1310         }
1311
1312         return err;
1313 }
1314 EXPORT_SYMBOL(inet_sk_rebuild_header);
1315
1316 void inet_sk_set_state(struct sock *sk, int state)
1317 {
1318         trace_inet_sock_set_state(sk, sk->sk_state, state);
1319         sk->sk_state = state;
1320 }
1321 EXPORT_SYMBOL(inet_sk_set_state);
1322
1323 void inet_sk_state_store(struct sock *sk, int newstate)
1324 {
1325         trace_inet_sock_set_state(sk, sk->sk_state, newstate);
1326         smp_store_release(&sk->sk_state, newstate);
1327 }
1328
1329 struct sk_buff *inet_gso_segment(struct sk_buff *skb,
1330                                  netdev_features_t features)
1331 {
1332         bool udpfrag = false, fixedid = false, gso_partial, encap;
1333         struct sk_buff *segs = ERR_PTR(-EINVAL);
1334         const struct net_offload *ops;
1335         unsigned int offset = 0;
1336         struct iphdr *iph;
1337         int proto, tot_len;
1338         int nhoff;
1339         int ihl;
1340         int id;
1341
1342         skb_reset_network_header(skb);
1343         nhoff = skb_network_header(skb) - skb_mac_header(skb);
1344         if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
1345                 goto out;
1346
1347         iph = ip_hdr(skb);
1348         ihl = iph->ihl * 4;
1349         if (ihl < sizeof(*iph))
1350                 goto out;
1351
1352         id = ntohs(iph->id);
1353         proto = iph->protocol;
1354
1355         /* Warning: after this point, iph might be no longer valid */
1356         if (unlikely(!pskb_may_pull(skb, ihl)))
1357                 goto out;
1358         __skb_pull(skb, ihl);
1359
1360         encap = SKB_GSO_CB(skb)->encap_level > 0;
1361         if (encap)
1362                 features &= skb->dev->hw_enc_features;
1363         SKB_GSO_CB(skb)->encap_level += ihl;
1364
1365         skb_reset_transport_header(skb);
1366
1367         segs = ERR_PTR(-EPROTONOSUPPORT);
1368
1369         if (!skb->encapsulation || encap) {
1370                 udpfrag = !!(skb_shinfo(skb)->gso_type & SKB_GSO_UDP);
1371                 fixedid = !!(skb_shinfo(skb)->gso_type & SKB_GSO_TCP_FIXEDID);
1372
1373                 /* fixed ID is invalid if DF bit is not set */
1374                 if (fixedid && !(ip_hdr(skb)->frag_off & htons(IP_DF)))
1375                         goto out;
1376         }
1377
1378         ops = rcu_dereference(inet_offloads[proto]);
1379         if (likely(ops && ops->callbacks.gso_segment)) {
1380                 segs = ops->callbacks.gso_segment(skb, features);
1381                 if (!segs)
1382                         skb->network_header = skb_mac_header(skb) + nhoff - skb->head;
1383         }
1384
1385         if (IS_ERR_OR_NULL(segs))
1386                 goto out;
1387
1388         gso_partial = !!(skb_shinfo(segs)->gso_type & SKB_GSO_PARTIAL);
1389
1390         skb = segs;
1391         do {
1392                 iph = (struct iphdr *)(skb_mac_header(skb) + nhoff);
1393                 if (udpfrag) {
1394                         iph->frag_off = htons(offset >> 3);
1395                         if (skb->next)
1396                                 iph->frag_off |= htons(IP_MF);
1397                         offset += skb->len - nhoff - ihl;
1398                         tot_len = skb->len - nhoff;
1399                 } else if (skb_is_gso(skb)) {
1400                         if (!fixedid) {
1401                                 iph->id = htons(id);
1402                                 id += skb_shinfo(skb)->gso_segs;
1403                         }
1404
1405                         if (gso_partial)
1406                                 tot_len = skb_shinfo(skb)->gso_size +
1407                                           SKB_GSO_CB(skb)->data_offset +
1408                                           skb->head - (unsigned char *)iph;
1409                         else
1410                                 tot_len = skb->len - nhoff;
1411                 } else {
1412                         if (!fixedid)
1413                                 iph->id = htons(id++);
1414                         tot_len = skb->len - nhoff;
1415                 }
1416                 iph->tot_len = htons(tot_len);
1417                 ip_send_check(iph);
1418                 if (encap)
1419                         skb_reset_inner_headers(skb);
1420                 skb->network_header = (u8 *)iph - skb->head;
1421                 skb_reset_mac_len(skb);
1422         } while ((skb = skb->next));
1423
1424 out:
1425         return segs;
1426 }
1427
1428 static struct sk_buff *ipip_gso_segment(struct sk_buff *skb,
1429                                         netdev_features_t features)
1430 {
1431         if (!(skb_shinfo(skb)->gso_type & SKB_GSO_IPXIP4))
1432                 return ERR_PTR(-EINVAL);
1433
1434         return inet_gso_segment(skb, features);
1435 }
1436
1437 struct sk_buff *inet_gro_receive(struct list_head *head, struct sk_buff *skb)
1438 {
1439         const struct net_offload *ops;
1440         struct sk_buff *pp = NULL;
1441         const struct iphdr *iph;
1442         struct sk_buff *p;
1443         unsigned int hlen;
1444         unsigned int off;
1445         unsigned int id;
1446         int flush = 1;
1447         int proto;
1448
1449         off = skb_gro_offset(skb);
1450         hlen = off + sizeof(*iph);
1451         iph = skb_gro_header_fast(skb, off);
1452         if (skb_gro_header_hard(skb, hlen)) {
1453                 iph = skb_gro_header_slow(skb, hlen, off);
1454                 if (unlikely(!iph))
1455                         goto out;
1456         }
1457
1458         proto = iph->protocol;
1459
1460         ops = rcu_dereference(inet_offloads[proto]);
1461         if (!ops || !ops->callbacks.gro_receive)
1462                 goto out;
1463
1464         if (*(u8 *)iph != 0x45)
1465                 goto out;
1466
1467         if (ip_is_fragment(iph))
1468                 goto out;
1469
1470         if (unlikely(ip_fast_csum((u8 *)iph, 5)))
1471                 goto out;
1472
1473         id = ntohl(*(__be32 *)&iph->id);
1474         flush = (u16)((ntohl(*(__be32 *)iph) ^ skb_gro_len(skb)) | (id & ~IP_DF));
1475         id >>= 16;
1476
1477         list_for_each_entry(p, head, list) {
1478                 struct iphdr *iph2;
1479                 u16 flush_id;
1480
1481                 if (!NAPI_GRO_CB(p)->same_flow)
1482                         continue;
1483
1484                 iph2 = (struct iphdr *)(p->data + off);
1485                 /* The above works because, with the exception of the top
1486                  * (inner most) layer, we only aggregate pkts with the same
1487                  * hdr length so all the hdrs we'll need to verify will start
1488                  * at the same offset.
1489                  */
1490                 if ((iph->protocol ^ iph2->protocol) |
1491                     ((__force u32)iph->saddr ^ (__force u32)iph2->saddr) |
1492                     ((__force u32)iph->daddr ^ (__force u32)iph2->daddr)) {
1493                         NAPI_GRO_CB(p)->same_flow = 0;
1494                         continue;
1495                 }
1496
1497                 /* All fields must match except length and checksum. */
1498                 NAPI_GRO_CB(p)->flush |=
1499                         (iph->ttl ^ iph2->ttl) |
1500                         (iph->tos ^ iph2->tos) |
1501                         ((iph->frag_off ^ iph2->frag_off) & htons(IP_DF));
1502
1503                 NAPI_GRO_CB(p)->flush |= flush;
1504
1505                 /* We need to store of the IP ID check to be included later
1506                  * when we can verify that this packet does in fact belong
1507                  * to a given flow.
1508                  */
1509                 flush_id = (u16)(id - ntohs(iph2->id));
1510
1511                 /* This bit of code makes it much easier for us to identify
1512                  * the cases where we are doing atomic vs non-atomic IP ID
1513                  * checks.  Specifically an atomic check can return IP ID
1514                  * values 0 - 0xFFFF, while a non-atomic check can only
1515                  * return 0 or 0xFFFF.
1516                  */
1517                 if (!NAPI_GRO_CB(p)->is_atomic ||
1518                     !(iph->frag_off & htons(IP_DF))) {
1519                         flush_id ^= NAPI_GRO_CB(p)->count;
1520                         flush_id = flush_id ? 0xFFFF : 0;
1521                 }
1522
1523                 /* If the previous IP ID value was based on an atomic
1524                  * datagram we can overwrite the value and ignore it.
1525                  */
1526                 if (NAPI_GRO_CB(skb)->is_atomic)
1527                         NAPI_GRO_CB(p)->flush_id = flush_id;
1528                 else
1529                         NAPI_GRO_CB(p)->flush_id |= flush_id;
1530         }
1531
1532         NAPI_GRO_CB(skb)->is_atomic = !!(iph->frag_off & htons(IP_DF));
1533         NAPI_GRO_CB(skb)->flush |= flush;
1534         skb_set_network_header(skb, off);
1535         /* The above will be needed by the transport layer if there is one
1536          * immediately following this IP hdr.
1537          */
1538
1539         /* Note : No need to call skb_gro_postpull_rcsum() here,
1540          * as we already checked checksum over ipv4 header was 0
1541          */
1542         skb_gro_pull(skb, sizeof(*iph));
1543         skb_set_transport_header(skb, skb_gro_offset(skb));
1544
1545         pp = indirect_call_gro_receive(tcp4_gro_receive, udp4_gro_receive,
1546                                        ops->callbacks.gro_receive, head, skb);
1547
1548 out:
1549         skb_gro_flush_final(skb, pp, flush);
1550
1551         return pp;
1552 }
1553
1554 static struct sk_buff *ipip_gro_receive(struct list_head *head,
1555                                         struct sk_buff *skb)
1556 {
1557         if (NAPI_GRO_CB(skb)->encap_mark) {
1558                 NAPI_GRO_CB(skb)->flush = 1;
1559                 return NULL;
1560         }
1561
1562         NAPI_GRO_CB(skb)->encap_mark = 1;
1563
1564         return inet_gro_receive(head, skb);
1565 }
1566
1567 #define SECONDS_PER_DAY 86400
1568
1569 /* inet_current_timestamp - Return IP network timestamp
1570  *
1571  * Return milliseconds since midnight in network byte order.
1572  */
1573 __be32 inet_current_timestamp(void)
1574 {
1575         u32 secs;
1576         u32 msecs;
1577         struct timespec64 ts;
1578
1579         ktime_get_real_ts64(&ts);
1580
1581         /* Get secs since midnight. */
1582         (void)div_u64_rem(ts.tv_sec, SECONDS_PER_DAY, &secs);
1583         /* Convert to msecs. */
1584         msecs = secs * MSEC_PER_SEC;
1585         /* Convert nsec to msec. */
1586         msecs += (u32)ts.tv_nsec / NSEC_PER_MSEC;
1587
1588         /* Convert to network byte order. */
1589         return htonl(msecs);
1590 }
1591 EXPORT_SYMBOL(inet_current_timestamp);
1592
1593 int inet_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
1594 {
1595         if (sk->sk_family == AF_INET)
1596                 return ip_recv_error(sk, msg, len, addr_len);
1597 #if IS_ENABLED(CONFIG_IPV6)
1598         if (sk->sk_family == AF_INET6)
1599                 return pingv6_ops.ipv6_recv_error(sk, msg, len, addr_len);
1600 #endif
1601         return -EINVAL;
1602 }
1603
1604 int inet_gro_complete(struct sk_buff *skb, int nhoff)
1605 {
1606         __be16 newlen = htons(skb->len - nhoff);
1607         struct iphdr *iph = (struct iphdr *)(skb->data + nhoff);
1608         const struct net_offload *ops;
1609         int proto = iph->protocol;
1610         int err = -ENOSYS;
1611
1612         if (skb->encapsulation) {
1613                 skb_set_inner_protocol(skb, cpu_to_be16(ETH_P_IP));
1614                 skb_set_inner_network_header(skb, nhoff);
1615         }
1616
1617         csum_replace2(&iph->check, iph->tot_len, newlen);
1618         iph->tot_len = newlen;
1619
1620         ops = rcu_dereference(inet_offloads[proto]);
1621         if (WARN_ON(!ops || !ops->callbacks.gro_complete))
1622                 goto out;
1623
1624         /* Only need to add sizeof(*iph) to get to the next hdr below
1625          * because any hdr with option will have been flushed in
1626          * inet_gro_receive().
1627          */
1628         err = INDIRECT_CALL_2(ops->callbacks.gro_complete,
1629                               tcp4_gro_complete, udp4_gro_complete,
1630                               skb, nhoff + sizeof(*iph));
1631
1632 out:
1633         return err;
1634 }
1635
1636 static int ipip_gro_complete(struct sk_buff *skb, int nhoff)
1637 {
1638         skb->encapsulation = 1;
1639         skb_shinfo(skb)->gso_type |= SKB_GSO_IPXIP4;
1640         return inet_gro_complete(skb, nhoff);
1641 }
1642
1643 int inet_ctl_sock_create(struct sock **sk, unsigned short family,
1644                          unsigned short type, unsigned char protocol,
1645                          struct net *net)
1646 {
1647         struct socket *sock;
1648         int rc = sock_create_kern(net, family, type, protocol, &sock);
1649
1650         if (rc == 0) {
1651                 *sk = sock->sk;
1652                 (*sk)->sk_allocation = GFP_ATOMIC;
1653                 /*
1654                  * Unhash it so that IP input processing does not even see it,
1655                  * we do not wish this socket to see incoming packets.
1656                  */
1657                 (*sk)->sk_prot->unhash(*sk);
1658         }
1659         return rc;
1660 }
1661 EXPORT_SYMBOL_GPL(inet_ctl_sock_create);
1662
1663 unsigned long snmp_fold_field(void __percpu *mib, int offt)
1664 {
1665         unsigned long res = 0;
1666         int i;
1667
1668         for_each_possible_cpu(i)
1669                 res += snmp_get_cpu_field(mib, i, offt);
1670         return res;
1671 }
1672 EXPORT_SYMBOL_GPL(snmp_fold_field);
1673
1674 #if BITS_PER_LONG==32
1675
1676 u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offt,
1677                          size_t syncp_offset)
1678 {
1679         void *bhptr;
1680         struct u64_stats_sync *syncp;
1681         u64 v;
1682         unsigned int start;
1683
1684         bhptr = per_cpu_ptr(mib, cpu);
1685         syncp = (struct u64_stats_sync *)(bhptr + syncp_offset);
1686         do {
1687                 start = u64_stats_fetch_begin_irq(syncp);
1688                 v = *(((u64 *)bhptr) + offt);
1689         } while (u64_stats_fetch_retry_irq(syncp, start));
1690
1691         return v;
1692 }
1693 EXPORT_SYMBOL_GPL(snmp_get_cpu_field64);
1694
1695 u64 snmp_fold_field64(void __percpu *mib, int offt, size_t syncp_offset)
1696 {
1697         u64 res = 0;
1698         int cpu;
1699
1700         for_each_possible_cpu(cpu) {
1701                 res += snmp_get_cpu_field64(mib, cpu, offt, syncp_offset);
1702         }
1703         return res;
1704 }
1705 EXPORT_SYMBOL_GPL(snmp_fold_field64);
1706 #endif
1707
1708 #ifdef CONFIG_IP_MULTICAST
1709 static const struct net_protocol igmp_protocol = {
1710         .handler =      igmp_rcv,
1711 };
1712 #endif
1713
1714 /* thinking of making this const? Don't.
1715  * early_demux can change based on sysctl.
1716  */
1717 static struct net_protocol tcp_protocol = {
1718         .early_demux    =       tcp_v4_early_demux,
1719         .early_demux_handler =  tcp_v4_early_demux,
1720         .handler        =       tcp_v4_rcv,
1721         .err_handler    =       tcp_v4_err,
1722         .no_policy      =       1,
1723         .icmp_strict_tag_validation = 1,
1724 };
1725
1726 /* thinking of making this const? Don't.
1727  * early_demux can change based on sysctl.
1728  */
1729 static struct net_protocol udp_protocol = {
1730         .early_demux =  udp_v4_early_demux,
1731         .early_demux_handler =  udp_v4_early_demux,
1732         .handler =      udp_rcv,
1733         .err_handler =  udp_err,
1734         .no_policy =    1,
1735 };
1736
1737 static const struct net_protocol icmp_protocol = {
1738         .handler =      icmp_rcv,
1739         .err_handler =  icmp_err,
1740         .no_policy =    1,
1741 };
1742
1743 static __net_init int ipv4_mib_init_net(struct net *net)
1744 {
1745         int i;
1746
1747         net->mib.tcp_statistics = alloc_percpu(struct tcp_mib);
1748         if (!net->mib.tcp_statistics)
1749                 goto err_tcp_mib;
1750         net->mib.ip_statistics = alloc_percpu(struct ipstats_mib);
1751         if (!net->mib.ip_statistics)
1752                 goto err_ip_mib;
1753
1754         for_each_possible_cpu(i) {
1755                 struct ipstats_mib *af_inet_stats;
1756                 af_inet_stats = per_cpu_ptr(net->mib.ip_statistics, i);
1757                 u64_stats_init(&af_inet_stats->syncp);
1758         }
1759
1760         net->mib.net_statistics = alloc_percpu(struct linux_mib);
1761         if (!net->mib.net_statistics)
1762                 goto err_net_mib;
1763         net->mib.udp_statistics = alloc_percpu(struct udp_mib);
1764         if (!net->mib.udp_statistics)
1765                 goto err_udp_mib;
1766         net->mib.udplite_statistics = alloc_percpu(struct udp_mib);
1767         if (!net->mib.udplite_statistics)
1768                 goto err_udplite_mib;
1769         net->mib.icmp_statistics = alloc_percpu(struct icmp_mib);
1770         if (!net->mib.icmp_statistics)
1771                 goto err_icmp_mib;
1772         net->mib.icmpmsg_statistics = kzalloc(sizeof(struct icmpmsg_mib),
1773                                               GFP_KERNEL);
1774         if (!net->mib.icmpmsg_statistics)
1775                 goto err_icmpmsg_mib;
1776
1777         tcp_mib_init(net);
1778         return 0;
1779
1780 err_icmpmsg_mib:
1781         free_percpu(net->mib.icmp_statistics);
1782 err_icmp_mib:
1783         free_percpu(net->mib.udplite_statistics);
1784 err_udplite_mib:
1785         free_percpu(net->mib.udp_statistics);
1786 err_udp_mib:
1787         free_percpu(net->mib.net_statistics);
1788 err_net_mib:
1789         free_percpu(net->mib.ip_statistics);
1790 err_ip_mib:
1791         free_percpu(net->mib.tcp_statistics);
1792 err_tcp_mib:
1793         return -ENOMEM;
1794 }
1795
1796 static __net_exit void ipv4_mib_exit_net(struct net *net)
1797 {
1798         kfree(net->mib.icmpmsg_statistics);
1799         free_percpu(net->mib.icmp_statistics);
1800         free_percpu(net->mib.udplite_statistics);
1801         free_percpu(net->mib.udp_statistics);
1802         free_percpu(net->mib.net_statistics);
1803         free_percpu(net->mib.ip_statistics);
1804         free_percpu(net->mib.tcp_statistics);
1805 #ifdef CONFIG_MPTCP
1806         /* allocated on demand, see mptcp_init_sock() */
1807         free_percpu(net->mib.mptcp_statistics);
1808 #endif
1809 }
1810
1811 static __net_initdata struct pernet_operations ipv4_mib_ops = {
1812         .init = ipv4_mib_init_net,
1813         .exit = ipv4_mib_exit_net,
1814 };
1815
1816 static int __init init_ipv4_mibs(void)
1817 {
1818         return register_pernet_subsys(&ipv4_mib_ops);
1819 }
1820
1821 static __net_init int inet_init_net(struct net *net)
1822 {
1823         /*
1824          * Set defaults for local port range
1825          */
1826         seqlock_init(&net->ipv4.ip_local_ports.lock);
1827         net->ipv4.ip_local_ports.range[0] =  32768;
1828         net->ipv4.ip_local_ports.range[1] =  60999;
1829
1830         seqlock_init(&net->ipv4.ping_group_range.lock);
1831         /*
1832          * Sane defaults - nobody may create ping sockets.
1833          * Boot scripts should set this to distro-specific group.
1834          */
1835         net->ipv4.ping_group_range.range[0] = make_kgid(&init_user_ns, 1);
1836         net->ipv4.ping_group_range.range[1] = make_kgid(&init_user_ns, 0);
1837
1838         /* Default values for sysctl-controlled parameters.
1839          * We set them here, in case sysctl is not compiled.
1840          */
1841         net->ipv4.sysctl_ip_default_ttl = IPDEFTTL;
1842         net->ipv4.sysctl_ip_fwd_update_priority = 1;
1843         net->ipv4.sysctl_ip_dynaddr = 0;
1844         net->ipv4.sysctl_ip_early_demux = 1;
1845         net->ipv4.sysctl_udp_early_demux = 1;
1846         net->ipv4.sysctl_tcp_early_demux = 1;
1847         net->ipv4.sysctl_nexthop_compat_mode = 1;
1848 #ifdef CONFIG_SYSCTL
1849         net->ipv4.sysctl_ip_prot_sock = PROT_SOCK;
1850 #endif
1851
1852         /* Some igmp sysctl, whose values are always used */
1853         net->ipv4.sysctl_igmp_max_memberships = 20;
1854         net->ipv4.sysctl_igmp_max_msf = 10;
1855         /* IGMP reports for link-local multicast groups are enabled by default */
1856         net->ipv4.sysctl_igmp_llm_reports = 1;
1857         net->ipv4.sysctl_igmp_qrv = 2;
1858
1859         net->ipv4.sysctl_fib_notify_on_flag_change = 0;
1860
1861         return 0;
1862 }
1863
1864 static __net_initdata struct pernet_operations af_inet_ops = {
1865         .init = inet_init_net,
1866 };
1867
1868 static int __init init_inet_pernet_ops(void)
1869 {
1870         return register_pernet_subsys(&af_inet_ops);
1871 }
1872
1873 static int ipv4_proc_init(void);
1874
1875 /*
1876  *      IP protocol layer initialiser
1877  */
1878
1879 static struct packet_offload ip_packet_offload __read_mostly = {
1880         .type = cpu_to_be16(ETH_P_IP),
1881         .callbacks = {
1882                 .gso_segment = inet_gso_segment,
1883                 .gro_receive = inet_gro_receive,
1884                 .gro_complete = inet_gro_complete,
1885         },
1886 };
1887
1888 static const struct net_offload ipip_offload = {
1889         .callbacks = {
1890                 .gso_segment    = ipip_gso_segment,
1891                 .gro_receive    = ipip_gro_receive,
1892                 .gro_complete   = ipip_gro_complete,
1893         },
1894 };
1895
1896 static int __init ipip_offload_init(void)
1897 {
1898         return inet_add_offload(&ipip_offload, IPPROTO_IPIP);
1899 }
1900
1901 static int __init ipv4_offload_init(void)
1902 {
1903         /*
1904          * Add offloads
1905          */
1906         if (udpv4_offload_init() < 0)
1907                 pr_crit("%s: Cannot add UDP protocol offload\n", __func__);
1908         if (tcpv4_offload_init() < 0)
1909                 pr_crit("%s: Cannot add TCP protocol offload\n", __func__);
1910         if (ipip_offload_init() < 0)
1911                 pr_crit("%s: Cannot add IPIP protocol offload\n", __func__);
1912
1913         dev_add_offload(&ip_packet_offload);
1914         return 0;
1915 }
1916
1917 fs_initcall(ipv4_offload_init);
1918
1919 static struct packet_type ip_packet_type __read_mostly = {
1920         .type = cpu_to_be16(ETH_P_IP),
1921         .func = ip_rcv,
1922         .list_func = ip_list_rcv,
1923 };
1924
1925 static int __init inet_init(void)
1926 {
1927         struct inet_protosw *q;
1928         struct list_head *r;
1929         int rc;
1930
1931         sock_skb_cb_check_size(sizeof(struct inet_skb_parm));
1932
1933         rc = proto_register(&tcp_prot, 1);
1934         if (rc)
1935                 goto out;
1936
1937         rc = proto_register(&udp_prot, 1);
1938         if (rc)
1939                 goto out_unregister_tcp_proto;
1940
1941         rc = proto_register(&raw_prot, 1);
1942         if (rc)
1943                 goto out_unregister_udp_proto;
1944
1945         rc = proto_register(&ping_prot, 1);
1946         if (rc)
1947                 goto out_unregister_raw_proto;
1948
1949         /*
1950          *      Tell SOCKET that we are alive...
1951          */
1952
1953         (void)sock_register(&inet_family_ops);
1954
1955 #ifdef CONFIG_SYSCTL
1956         ip_static_sysctl_init();
1957 #endif
1958
1959         /*
1960          *      Add all the base protocols.
1961          */
1962
1963         if (inet_add_protocol(&icmp_protocol, IPPROTO_ICMP) < 0)
1964                 pr_crit("%s: Cannot add ICMP protocol\n", __func__);
1965         if (inet_add_protocol(&udp_protocol, IPPROTO_UDP) < 0)
1966                 pr_crit("%s: Cannot add UDP protocol\n", __func__);
1967         if (inet_add_protocol(&tcp_protocol, IPPROTO_TCP) < 0)
1968                 pr_crit("%s: Cannot add TCP protocol\n", __func__);
1969 #ifdef CONFIG_IP_MULTICAST
1970         if (inet_add_protocol(&igmp_protocol, IPPROTO_IGMP) < 0)
1971                 pr_crit("%s: Cannot add IGMP protocol\n", __func__);
1972 #endif
1973
1974         /* Register the socket-side information for inet_create. */
1975         for (r = &inetsw[0]; r < &inetsw[SOCK_MAX]; ++r)
1976                 INIT_LIST_HEAD(r);
1977
1978         for (q = inetsw_array; q < &inetsw_array[INETSW_ARRAY_LEN]; ++q)
1979                 inet_register_protosw(q);
1980
1981         /*
1982          *      Set the ARP module up
1983          */
1984
1985         arp_init();
1986
1987         /*
1988          *      Set the IP module up
1989          */
1990
1991         ip_init();
1992
1993         /* Initialise per-cpu ipv4 mibs */
1994         if (init_ipv4_mibs())
1995                 panic("%s: Cannot init ipv4 mibs\n", __func__);
1996
1997         /* Setup TCP slab cache for open requests. */
1998         tcp_init();
1999
2000         /* Setup UDP memory threshold */
2001         udp_init();
2002
2003         /* Add UDP-Lite (RFC 3828) */
2004         udplite4_register();
2005
2006         raw_init();
2007
2008         ping_init();
2009
2010         /*
2011          *      Set the ICMP layer up
2012          */
2013
2014         if (icmp_init() < 0)
2015                 panic("Failed to create the ICMP control socket.\n");
2016
2017         /*
2018          *      Initialise the multicast router
2019          */
2020 #if defined(CONFIG_IP_MROUTE)
2021         if (ip_mr_init())
2022                 pr_crit("%s: Cannot init ipv4 mroute\n", __func__);
2023 #endif
2024
2025         if (init_inet_pernet_ops())
2026                 pr_crit("%s: Cannot init ipv4 inet pernet ops\n", __func__);
2027
2028         ipv4_proc_init();
2029
2030         ipfrag_init();
2031
2032         dev_add_pack(&ip_packet_type);
2033
2034         ip_tunnel_core_init();
2035
2036         rc = 0;
2037 out:
2038         return rc;
2039 out_unregister_raw_proto:
2040         proto_unregister(&raw_prot);
2041 out_unregister_udp_proto:
2042         proto_unregister(&udp_prot);
2043 out_unregister_tcp_proto:
2044         proto_unregister(&tcp_prot);
2045         goto out;
2046 }
2047
2048 fs_initcall(inet_init);
2049
2050 /* ------------------------------------------------------------------------ */
2051
2052 #ifdef CONFIG_PROC_FS
2053 static int __init ipv4_proc_init(void)
2054 {
2055         int rc = 0;
2056
2057         if (raw_proc_init())
2058                 goto out_raw;
2059         if (tcp4_proc_init())
2060                 goto out_tcp;
2061         if (udp4_proc_init())
2062                 goto out_udp;
2063         if (ping_proc_init())
2064                 goto out_ping;
2065         if (ip_misc_proc_init())
2066                 goto out_misc;
2067 out:
2068         return rc;
2069 out_misc:
2070         ping_proc_exit();
2071 out_ping:
2072         udp4_proc_exit();
2073 out_udp:
2074         tcp4_proc_exit();
2075 out_tcp:
2076         raw_proc_exit();
2077 out_raw:
2078         rc = -ENOMEM;
2079         goto out;
2080 }
2081
2082 #else /* CONFIG_PROC_FS */
2083 static int __init ipv4_proc_init(void)
2084 {
2085         return 0;
2086 }
2087 #endif /* CONFIG_PROC_FS */