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/tcp.h>
 103 #include <net/udp.h>
 104 #include <net/udplite.h>
 105 #include <net/ping.h>
 106 #include <linux/skbuff.h>
 107 #include <net/sock.h>
 108 #include <net/raw.h>
 109 #include <net/icmp.h>
 110 #include <net/inet_common.h>
 111 #include <net/ip_tunnels.h>
 112 #include <net/xfrm.h>
 113 #include <net/net_namespace.h>
 114 #include <net/secure_seq.h>
 115 #ifdef CONFIG_IP_MROUTE
 116 #include <linux/mroute.h>
 117 #endif
 118 #include <net/l3mdev.h>
 119 #include <net/compat.h>
 120
 121 #include <trace/events/sock.h>
 122
 123 /* The inetsw table contains everything that inet_create needs to
 124  * build a new socket.
 125  */
 126 static struct list_head inetsw[SOCK_MAX];
 127 static DEFINE_SPINLOCK(inetsw_lock);
 128
 129 /* New destruction routine */
 130
 131 void inet_sock_destruct(struct sock *sk)
 132 {
 133         struct inet_sock *inet = inet_sk(sk);
 134
 135         __skb_queue_purge(&sk->sk_receive_queue);
 136         if (sk->sk_rx_skb_cache) {
 137                 __kfree_skb(sk->sk_rx_skb_cache);
 138                 sk->sk_rx_skb_cache = NULL;
 139         }
 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(refcount_read(&sk->sk_wmem_alloc));
 156         WARN_ON(sk->sk_wmem_queued);
 157         WARN_ON(sk->sk_forward_alloc);
 158
 159         kfree(rcu_dereference_protected(inet->inet_opt, 1));
 160         dst_release(rcu_dereference_protected(sk->sk_dst_cache, 1));
 161         dst_release(sk->sk_rx_dst);
 162         sk_refcnt_debug_dec(sk);
 163 }
 164 EXPORT_SYMBOL(inet_sock_destruct);
 165
 166 /*
 167  *      The routines beyond this point handle the behaviour of an AF_INET
 168  *      socket object. Mostly it punts to the subprotocols of IP to do
 169  *      the work.
 170  */
 171
 172 /*
 173  *      Automatically bind an unbound socket.
 174  */
 175
 176 static int inet_autobind(struct sock *sk)
 177 {
 178         struct inet_sock *inet;
 179         /* We may need to bind the socket. */
 180         lock_sock(sk);
 181         inet = inet_sk(sk);
 182         if (!inet->inet_num) {
 183                 if (sk->sk_prot->get_port(sk, 0)) {
 184                         release_sock(sk);
 185                         return -EAGAIN;
 186                 }
 187                 inet->inet_sport = htons(inet->inet_num);
 188         }
 189         release_sock(sk);
 190         return 0;
 191 }
 192
 193 /*
 194  *      Move a socket into listening state.
 195  */
 196 int inet_listen(struct socket *sock, int backlog)
 197 {
 198         struct sock *sk = sock->sk;
 199         unsigned char old_state;
 200         int err, tcp_fastopen;
 201
 202         lock_sock(sk);
 203
 204         err = -EINVAL;
 205         if (sock->state != SS_UNCONNECTED || sock->type != SOCK_STREAM)
 206                 goto out;
 207
 208         old_state = sk->sk_state;
 209         if (!((1 << old_state) & (TCPF_CLOSE | TCPF_LISTEN)))
 210                 goto out;
 211
 212         WRITE_ONCE(sk->sk_max_ack_backlog, backlog);
 213         /* Really, if the socket is already in listen state
 214          * we can only allow the backlog to be adjusted.
 215          */
 216         if (old_state != TCP_LISTEN) {
 217                 /* Enable TFO w/o requiring TCP_FASTOPEN socket option.
 218                  * Note that only TCP sockets (SOCK_STREAM) will reach here.
 219                  * Also fastopen backlog may already been set via the option
 220                  * because the socket was in TCP_LISTEN state previously but
 221                  * was shutdown() rather than close().
 222                  */
 223                 tcp_fastopen = sock_net(sk)->ipv4.sysctl_tcp_fastopen;
 224                 if ((tcp_fastopen & TFO_SERVER_WO_SOCKOPT1) &&
 225                     (tcp_fastopen & TFO_SERVER_ENABLE) &&
 226                     !inet_csk(sk)->icsk_accept_queue.fastopenq.max_qlen) {
 227                         fastopen_queue_tune(sk, backlog);
 228                         tcp_fastopen_init_key_once(sock_net(sk));
 229                 }
 230
 231                 err = inet_csk_listen_start(sk, backlog);
 232                 if (err)
 233                         goto out;
 234                 tcp_call_bpf(sk, BPF_SOCK_OPS_TCP_LISTEN_CB, 0, NULL);
 235         }
 236         err = 0;
 237
 238 out:
 239         release_sock(sk);
 240         return err;
 241 }
 242 EXPORT_SYMBOL(inet_listen);
 243
 244 /*
 245  *      Create an inet socket.
 246  */
 247
 248 static int inet_create(struct net *net, struct socket *sock, int protocol,
 249                        int kern)
 250 {
 251         struct sock *sk;
 252         struct inet_protosw *answer;
 253         struct inet_sock *inet;
 254         struct proto *answer_prot;
 255         unsigned char answer_flags;
 256         int try_loading_module = 0;
 257         int err;
 258
 259         if (protocol < 0 || protocol >= IPPROTO_MAX)
 260                 return -EINVAL;
 261
 262         sock->state = SS_UNCONNECTED;
 263
 264         /* Look for the requested type/protocol pair. */
 265 lookup_protocol:
 266         err = -ESOCKTNOSUPPORT;
 267         rcu_read_lock();
 268         list_for_each_entry_rcu(answer, &inetsw[sock->type], list) {
 269
 270                 err = 0;
 271                 /* Check the non-wild match. */
 272                 if (protocol == answer->protocol) {
 273                         if (protocol != IPPROTO_IP)
 274                                 break;
 275                 } else {
 276                         /* Check for the two wild cases. */
 277                         if (IPPROTO_IP == protocol) {
 278                                 protocol = answer->protocol;
 279                                 break;
 280                         }
 281                         if (IPPROTO_IP == answer->protocol)
 282                                 break;
 283                 }
 284                 err = -EPROTONOSUPPORT;
 285         }
 286
 287         if (unlikely(err)) {
 288                 if (try_loading_module < 2) {
 289                         rcu_read_unlock();
 290                         /*
 291                          * Be more specific, e.g. net-pf-2-proto-132-type-1
 292                          * (net-pf-PF_INET-proto-IPPROTO_SCTP-type-SOCK_STREAM)
 293                          */
 294                         if (++try_loading_module == 1)
 295                                 request_module("net-pf-%d-proto-%d-type-%d",
 296                                                PF_INET, protocol, sock->type);
 297                         /*
 298                          * Fall back to generic, e.g. net-pf-2-proto-132
 299                          * (net-pf-PF_INET-proto-IPPROTO_SCTP)
 300                          */
 301                         else
 302                                 request_module("net-pf-%d-proto-%d",
 303                                                PF_INET, protocol);
 304                         goto lookup_protocol;
 305                 } else
 306                         goto out_rcu_unlock;
 307         }
 308
 309         err = -EPERM;
 310         if (sock->type == SOCK_RAW && !kern &&
 311             !ns_capable(net->user_ns, CAP_NET_RAW))
 312                 goto out_rcu_unlock;
 313
 314         sock->ops = answer->ops;
 315         answer_prot = answer->prot;
 316         answer_flags = answer->flags;
 317         rcu_read_unlock();
 318
 319         WARN_ON(!answer_prot->slab);
 320
 321         err = -ENOBUFS;
 322         sk = sk_alloc(net, PF_INET, GFP_KERNEL, answer_prot, kern);
 323         if (!sk)
 324                 goto out;
 325
 326         err = 0;
 327         if (INET_PROTOSW_REUSE & answer_flags)
 328                 sk->sk_reuse = SK_CAN_REUSE;
 329
 330         inet = inet_sk(sk);
 331         inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
 332
 333         inet->nodefrag = 0;
 334
 335         if (SOCK_RAW == sock->type) {
 336                 inet->inet_num = protocol;
 337                 if (IPPROTO_RAW == protocol)
 338                         inet->hdrincl = 1;
 339         }
 340
 341         if (net->ipv4.sysctl_ip_no_pmtu_disc)
 342                 inet->pmtudisc = IP_PMTUDISC_DONT;
 343         else
 344                 inet->pmtudisc = IP_PMTUDISC_WANT;
 345
 346         inet->inet_id = 0;
 347
 348         sock_init_data(sock, sk);
 349
 350         sk->sk_destruct    = inet_sock_destruct;
 351         sk->sk_protocol    = protocol;
 352         sk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
 353
 354         inet->uc_ttl    = -1;
 355         inet->mc_loop   = 1;
 356         inet->mc_ttl    = 1;
 357         inet->mc_all    = 1;
 358         inet->mc_index  = 0;
 359         inet->mc_list   = NULL;
 360         inet->rcv_tos   = 0;
 361
 362         sk_refcnt_debug_inc(sk);
 363
 364         if (inet->inet_num) {
 365                 /* It assumes that any protocol which allows
 366                  * the user to assign a number at socket
 367                  * creation time automatically
 368                  * shares.
 369                  */
 370                 inet->inet_sport = htons(inet->inet_num);
 371                 /* Add to protocol hash chains. */
 372                 err = sk->sk_prot->hash(sk);
 373                 if (err) {
 374                         sk_common_release(sk);
 375                         goto out;
 376                 }
 377         }
 378
 379         if (sk->sk_prot->init) {
 380                 err = sk->sk_prot->init(sk);
 381                 if (err) {
 382                         sk_common_release(sk);
 383                         goto out;
 384                 }
 385         }
 386
 387         if (!kern) {
 388                 err = BPF_CGROUP_RUN_PROG_INET_SOCK(sk);
 389                 if (err) {
 390                         sk_common_release(sk);
 391                         goto out;
 392                 }
 393         }
 394 out:
 395         return err;
 396 out_rcu_unlock:
 397         rcu_read_unlock();
 398         goto out;
 399 }
 400
 401
 402 /*
 403  *      The peer socket should always be NULL (or else). When we call this
 404  *      function we are destroying the object and from then on nobody
 405  *      should refer to it.
 406  */
 407 int inet_release(struct socket *sock)
 408 {
 409         struct sock *sk = sock->sk;
 410
 411         if (sk) {
 412                 long timeout;
 413
 414                 if (!sk->sk_kern_sock)
 415                         BPF_CGROUP_RUN_PROG_INET_SOCK_RELEASE(sk);
 416
 417                 /* Applications forget to leave groups before exiting */
 418                 ip_mc_drop_socket(sk);
 419
 420                 /* If linger is set, we don't return until the close
 421                  * is complete.  Otherwise we return immediately. The
 422                  * actually closing is done the same either way.
 423                  *
 424                  * If the close is due to the process exiting, we never
 425                  * linger..
 426                  */
 427                 timeout = 0;
 428                 if (sock_flag(sk, SOCK_LINGER) &&
 429                     !(current->flags & PF_EXITING))
 430                         timeout = sk->sk_lingertime;
 431                 sk->sk_prot->close(sk, timeout);
 432                 sock->sk = NULL;
 433         }
 434         return 0;
 435 }
 436 EXPORT_SYMBOL(inet_release);
 437
 438 int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 439 {
 440         struct sock *sk = sock->sk;
 441         u32 flags = BIND_WITH_LOCK;
 442         int err;
 443
 444         /* If the socket has its own bind function then use it. (RAW) */
 445         if (sk->sk_prot->bind) {
 446                 return sk->sk_prot->bind(sk, uaddr, addr_len);
 447         }
 448         if (addr_len < sizeof(struct sockaddr_in))
 449                 return -EINVAL;
 450
 451         /* BPF prog is run before any checks are done so that if the prog
 452          * changes context in a wrong way it will be caught.
 453          */
 454         err = BPF_CGROUP_RUN_PROG_INET_BIND_LOCK(sk, uaddr,
 455                                                  BPF_CGROUP_INET4_BIND, &flags);
 456         if (err)
 457                 return err;
 458
 459         return __inet_bind(sk, uaddr, addr_len, flags);
 460 }
 461 EXPORT_SYMBOL(inet_bind);
 462
 463 int __inet_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len,
 464                 u32 flags)
 465 {
 466         struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
 467         struct inet_sock *inet = inet_sk(sk);
 468         struct net *net = sock_net(sk);
 469         unsigned short snum;
 470         int chk_addr_ret;
 471         u32 tb_id = RT_TABLE_LOCAL;
 472         int err;
 473
 474         if (addr->sin_family != AF_INET) {
 475                 /* Compatibility games : accept AF_UNSPEC (mapped to AF_INET)
 476                  * only if s_addr is INADDR_ANY.
 477                  */
 478                 err = -EAFNOSUPPORT;
 479                 if (addr->sin_family != AF_UNSPEC ||
 480                     addr->sin_addr.s_addr != htonl(INADDR_ANY))
 481                         goto out;
 482         }
 483
 484         tb_id = l3mdev_fib_table_by_index(net, sk->sk_bound_dev_if) ? : tb_id;
 485         chk_addr_ret = inet_addr_type_table(net, addr->sin_addr.s_addr, tb_id);
 486
 487         /* Not specified by any standard per-se, however it breaks too
 488          * many applications when removed.  It is unfortunate since
 489          * allowing applications to make a non-local bind solves
 490          * several problems with systems using dynamic addressing.
 491          * (ie. your servers still start up even if your ISDN link
 492          *  is temporarily down)
 493          */
 494         err = -EADDRNOTAVAIL;
 495         if (!inet_can_nonlocal_bind(net, inet) &&
 496             addr->sin_addr.s_addr != htonl(INADDR_ANY) &&
 497             chk_addr_ret != RTN_LOCAL &&
 498             chk_addr_ret != RTN_MULTICAST &&
 499             chk_addr_ret != RTN_BROADCAST)
 500                 goto out;
 501
 502         snum = ntohs(addr->sin_port);
 503         err = -EACCES;
 504         if (!(flags & BIND_NO_CAP_NET_BIND_SERVICE) &&
 505             snum && inet_port_requires_bind_service(net, snum) &&
 506             !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE))
 507                 goto out;
 508
 509         /*      We keep a pair of addresses. rcv_saddr is the one
 510          *      used by hash lookups, and saddr is used for transmit.
 511          *
 512          *      In the BSD API these are the same except where it
 513          *      would be illegal to use them (multicast/broadcast) in
 514          *      which case the sending device address is used.
 515          */
 516         if (flags & BIND_WITH_LOCK)
 517                 lock_sock(sk);
 518
 519         /* Check these errors (active socket, double bind). */
 520         err = -EINVAL;
 521         if (sk->sk_state != TCP_CLOSE || inet->inet_num)
 522                 goto out_release_sock;
 523
 524         inet->inet_rcv_saddr = inet->inet_saddr = addr->sin_addr.s_addr;
 525         if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST)
 526                 inet->inet_saddr = 0;  /* Use device */
 527
 528         /* Make sure we are allowed to bind here. */
 529         if (snum || !(inet->bind_address_no_port ||
 530                       (flags & BIND_FORCE_ADDRESS_NO_PORT))) {
 531                 if (sk->sk_prot->get_port(sk, snum)) {
 532                         inet->inet_saddr = inet->inet_rcv_saddr = 0;
 533                         err = -EADDRINUSE;
 534                         goto out_release_sock;
 535                 }
 536                 if (!(flags & BIND_FROM_BPF)) {
 537                         err = BPF_CGROUP_RUN_PROG_INET4_POST_BIND(sk);
 538                         if (err) {
 539                                 inet->inet_saddr = inet->inet_rcv_saddr = 0;
 540                                 goto out_release_sock;
 541                         }
 542                 }
 543         }
 544
 545         if (inet->inet_rcv_saddr)
 546                 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
 547         if (snum)
 548                 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
 549         inet->inet_sport = htons(inet->inet_num);
 550         inet->inet_daddr = 0;
 551         inet->inet_dport = 0;
 552         sk_dst_reset(sk);
 553         err = 0;
 554 out_release_sock:
 555         if (flags & BIND_WITH_LOCK)
 556                 release_sock(sk);
 557 out:
 558         return err;
 559 }
 560
 561 int inet_dgram_connect(struct socket *sock, struct sockaddr *uaddr,
 562                        int addr_len, int flags)
 563 {
 564         struct sock *sk = sock->sk;
 565         int err;
 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 (BPF_CGROUP_PRE_CONNECT_ENABLED(sk)) {
 573                 err = sk->sk_prot->pre_connect(sk, uaddr, addr_len);
 574                 if (err)
 575                         return err;
 576         }
 577
 578         if (!inet_sk(sk)->inet_num && inet_autobind(sk))
 579                 return -EAGAIN;
 580         return sk->sk_prot->connect(sk, uaddr, addr_len);
 581 }
 582 EXPORT_SYMBOL(inet_dgram_connect);
 583
 584 static long inet_wait_for_connect(struct sock *sk, long timeo, int writebias)
 585 {
 586         DEFINE_WAIT_FUNC(wait, woken_wake_function);
 587
 588         add_wait_queue(sk_sleep(sk), &wait);
 589         sk->sk_write_pending += writebias;
 590
 591         /* Basic assumption: if someone sets sk->sk_err, he _must_
 592          * change state of the socket from TCP_SYN_*.
 593          * Connect() does not allow to get error notifications
 594          * without closing the socket.
 595          */
 596         while ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
 597                 release_sock(sk);
 598                 timeo = wait_woken(&wait, TASK_INTERRUPTIBLE, timeo);
 599                 lock_sock(sk);
 600                 if (signal_pending(current) || !timeo)
 601                         break;
 602         }
 603         remove_wait_queue(sk_sleep(sk), &wait);
 604         sk->sk_write_pending -= writebias;
 605         return timeo;
 606 }
 607
 608 /*
 609  *      Connect to a remote host. There is regrettably still a little
 610  *      TCP 'magic' in here.
 611  */
 612 int __inet_stream_connect(struct socket *sock, struct sockaddr *uaddr,
 613                           int addr_len, int flags, int is_sendmsg)
 614 {
 615         struct sock *sk = sock->sk;
 616         int err;
 617         long timeo;
 618
 619         /*
 620          * uaddr can be NULL and addr_len can be 0 if:
 621          * sk is a TCP fastopen active socket and
 622          * TCP_FASTOPEN_CONNECT sockopt is set and
 623          * we already have a valid cookie for this socket.
 624          * In this case, user can call write() after connect().
 625          * write() will invoke tcp_sendmsg_fastopen() which calls
 626          * __inet_stream_connect().
 627          */
 628         if (uaddr) {
 629                 if (addr_len < sizeof(uaddr->sa_family))
 630                         return -EINVAL;
 631
 632                 if (uaddr->sa_family == AF_UNSPEC) {
 633                         err = sk->sk_prot->disconnect(sk, flags);
 634                         sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
 635                         goto out;
 636                 }
 637         }
 638
 639         switch (sock->state) {
 640         default:
 641                 err = -EINVAL;
 642                 goto out;
 643         case SS_CONNECTED:
 644                 err = -EISCONN;
 645                 goto out;
 646         case SS_CONNECTING:
 647                 if (inet_sk(sk)->defer_connect)
 648                         err = is_sendmsg ? -EINPROGRESS : -EISCONN;
 649                 else
 650                         err = -EALREADY;
 651                 /* Fall out of switch with err, set for this state */
 652                 break;
 653         case SS_UNCONNECTED:
 654                 err = -EISCONN;
 655                 if (sk->sk_state != TCP_CLOSE)
 656                         goto out;
 657
 658                 if (BPF_CGROUP_PRE_CONNECT_ENABLED(sk)) {
 659                         err = sk->sk_prot->pre_connect(sk, uaddr, addr_len);
 660                         if (err)
 661                                 goto out;
 662                 }
 663
 664                 err = sk->sk_prot->connect(sk, uaddr, addr_len);
 665                 if (err < 0)
 666                         goto out;
 667
 668                 sock->state = SS_CONNECTING;
 669
 670                 if (!err && inet_sk(sk)->defer_connect)
 671                         goto out;
 672
 673                 /* Just entered SS_CONNECTING state; the only
 674                  * difference is that return value in non-blocking
 675                  * case is EINPROGRESS, rather than EALREADY.
 676                  */
 677                 err = -EINPROGRESS;
 678                 break;
 679         }
 680
 681         timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
 682
 683         if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
 684                 int writebias = (sk->sk_protocol == IPPROTO_TCP) &&
 685                                 tcp_sk(sk)->fastopen_req &&
 686                                 tcp_sk(sk)->fastopen_req->data ? 1 : 0;
 687
 688                 /* Error code is set above */
 689                 if (!timeo || !inet_wait_for_connect(sk, timeo, writebias))
 690                         goto out;
 691
 692                 err = sock_intr_errno(timeo);
 693                 if (signal_pending(current))
 694                         goto out;
 695         }
 696
 697         /* Connection was closed by RST, timeout, ICMP error
 698          * or another process disconnected us.
 699          */
 700         if (sk->sk_state == TCP_CLOSE)
 701                 goto sock_error;
 702
 703         /* sk->sk_err may be not zero now, if RECVERR was ordered by user
 704          * and error was received after socket entered established state.
 705          * Hence, it is handled normally after connect() return successfully.
 706          */
 707
 708         sock->state = SS_CONNECTED;
 709         err = 0;
 710 out:
 711         return err;
 712
 713 sock_error:
 714         err = sock_error(sk) ? : -ECONNABORTED;
 715         sock->state = SS_UNCONNECTED;
 716         if (sk->sk_prot->disconnect(sk, flags))
 717                 sock->state = SS_DISCONNECTING;
 718         goto out;
 719 }
 720 EXPORT_SYMBOL(__inet_stream_connect);
 721
 722 int inet_stream_connect(struct socket *sock, struct sockaddr *uaddr,
 723                         int addr_len, int flags)
 724 {
 725         int err;
 726
 727         lock_sock(sock->sk);
 728         err = __inet_stream_connect(sock, uaddr, addr_len, flags, 0);
 729         release_sock(sock->sk);
 730         return err;
 731 }
 732 EXPORT_SYMBOL(inet_stream_connect);
 733
 734 /*
 735  *      Accept a pending connection. The TCP layer now gives BSD semantics.
 736  */
 737
 738 int inet_accept(struct socket *sock, struct socket *newsock, int flags,
 739                 bool kern)
 740 {
 741         struct sock *sk1 = sock->sk;
 742         int err = -EINVAL;
 743         struct sock *sk2 = sk1->sk_prot->accept(sk1, flags, &err, kern);
 744
 745         if (!sk2)
 746                 goto do_err;
 747
 748         lock_sock(sk2);
 749
 750         sock_rps_record_flow(sk2);
 751         WARN_ON(!((1 << sk2->sk_state) &
 752                   (TCPF_ESTABLISHED | TCPF_SYN_RECV |
 753                   TCPF_CLOSE_WAIT | TCPF_CLOSE)));
 754
 755         sock_graft(sk2, newsock);
 756
 757         newsock->state = SS_CONNECTED;
 758         err = 0;
 759         release_sock(sk2);
 760 do_err:
 761         return err;
 762 }
 763 EXPORT_SYMBOL(inet_accept);
 764
 765 /*
 766  *      This does both peername and sockname.
 767  */
 768 int inet_getname(struct socket *sock, struct sockaddr *uaddr,
 769                  int peer)
 770 {
 771         struct sock *sk         = sock->sk;
 772         struct inet_sock *inet  = inet_sk(sk);
 773         DECLARE_SOCKADDR(struct sockaddr_in *, sin, uaddr);
 774
 775         sin->sin_family = AF_INET;
 776         if (peer) {
 777                 if (!inet->inet_dport ||
 778                     (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
 779                      peer == 1))
 780                         return -ENOTCONN;
 781                 sin->sin_port = inet->inet_dport;
 782                 sin->sin_addr.s_addr = inet->inet_daddr;
 783                 BPF_CGROUP_RUN_SA_PROG_LOCK(sk, (struct sockaddr *)sin,
 784                                             BPF_CGROUP_INET4_GETPEERNAME,
 785                                             NULL);
 786         } else {
 787                 __be32 addr = inet->inet_rcv_saddr;
 788                 if (!addr)
 789                         addr = inet->inet_saddr;
 790                 sin->sin_port = inet->inet_sport;
 791                 sin->sin_addr.s_addr = addr;
 792                 BPF_CGROUP_RUN_SA_PROG_LOCK(sk, (struct sockaddr *)sin,
 793                                             BPF_CGROUP_INET4_GETSOCKNAME,
 794                                             NULL);
 795         }
 796         memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
 797         return sizeof(*sin);
 798 }
 799 EXPORT_SYMBOL(inet_getname);
 800
 801 int inet_send_prepare(struct sock *sk)
 802 {
 803         sock_rps_record_flow(sk);
 804
 805         /* We may need to bind the socket. */
 806         if (!inet_sk(sk)->inet_num && !sk->sk_prot->no_autobind &&
 807             inet_autobind(sk))
 808                 return -EAGAIN;
 809
 810         return 0;
 811 }
 812 EXPORT_SYMBOL_GPL(inet_send_prepare);
 813
 814 int inet_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
 815 {
 816         struct sock *sk = sock->sk;
 817
 818         if (unlikely(inet_send_prepare(sk)))
 819                 return -EAGAIN;
 820
 821         return INDIRECT_CALL_2(sk->sk_prot->sendmsg, tcp_sendmsg, udp_sendmsg,
 822                                sk, msg, size);
 823 }
 824 EXPORT_SYMBOL(inet_sendmsg);
 825
 826 ssize_t inet_sendpage(struct socket *sock, struct page *page, int offset,
 827                       size_t size, int flags)
 828 {
 829         struct sock *sk = sock->sk;
 830
 831         if (unlikely(inet_send_prepare(sk)))
 832                 return -EAGAIN;
 833
 834         if (sk->sk_prot->sendpage)
 835                 return sk->sk_prot->sendpage(sk, page, offset, size, flags);
 836         return sock_no_sendpage(sock, page, offset, size, flags);
 837 }
 838 EXPORT_SYMBOL(inet_sendpage);
 839
 840 INDIRECT_CALLABLE_DECLARE(int udp_recvmsg(struct sock *, struct msghdr *,
 841                                           size_t, int, int, int *));
 842 int inet_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
 843                  int flags)
 844 {
 845         struct sock *sk = sock->sk;
 846         int addr_len = 0;
 847         int err;
 848
 849         if (likely(!(flags & MSG_ERRQUEUE)))
 850                 sock_rps_record_flow(sk);
 851
 852         err = INDIRECT_CALL_2(sk->sk_prot->recvmsg, tcp_recvmsg, udp_recvmsg,
 853                               sk, msg, size, flags & MSG_DONTWAIT,
 854                               flags & ~MSG_DONTWAIT, &addr_len);
 855         if (err >= 0)
 856                 msg->msg_namelen = addr_len;
 857         return err;
 858 }
 859 EXPORT_SYMBOL(inet_recvmsg);
 860
 861 int inet_shutdown(struct socket *sock, int how)
 862 {
 863         struct sock *sk = sock->sk;
 864         int err = 0;
 865
 866         /* This should really check to make sure
 867          * the socket is a TCP socket. (WHY AC...)
 868          */
 869         how++; /* maps 0->1 has the advantage of making bit 1 rcvs and
 870                        1->2 bit 2 snds.
 871                        2->3 */
 872         if ((how & ~SHUTDOWN_MASK) || !how)     /* MAXINT->0 */
 873                 return -EINVAL;
 874
 875         lock_sock(sk);
 876         if (sock->state == SS_CONNECTING) {
 877                 if ((1 << sk->sk_state) &
 878                     (TCPF_SYN_SENT | TCPF_SYN_RECV | TCPF_CLOSE))
 879                         sock->state = SS_DISCONNECTING;
 880                 else
 881                         sock->state = SS_CONNECTED;
 882         }
 883
 884         switch (sk->sk_state) {
 885         case TCP_CLOSE:
 886                 err = -ENOTCONN;
 887                 /* Hack to wake up other listeners, who can poll for
 888                    EPOLLHUP, even on eg. unconnected UDP sockets -- RR */
 889                 fallthrough;
 890         default:
 891                 sk->sk_shutdown |= how;
 892                 if (sk->sk_prot->shutdown)
 893                         sk->sk_prot->shutdown(sk, how);
 894                 break;
 895
 896         /* Remaining two branches are temporary solution for missing
 897          * close() in multithreaded environment. It is _not_ a good idea,
 898          * but we have no choice until close() is repaired at VFS level.
 899          */
 900         case TCP_LISTEN:
 901                 if (!(how & RCV_SHUTDOWN))
 902                         break;
 903                 fallthrough;
 904         case TCP_SYN_SENT:
 905                 err = sk->sk_prot->disconnect(sk, O_NONBLOCK);
 906                 sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
 907                 break;
 908         }
 909
 910         /* Wake up anyone sleeping in poll. */
 911         sk->sk_state_change(sk);
 912         release_sock(sk);
 913         return err;
 914 }
 915 EXPORT_SYMBOL(inet_shutdown);
 916
 917 /*
 918  *      ioctl() calls you can issue on an INET socket. Most of these are
 919  *      device configuration and stuff and very rarely used. Some ioctls
 920  *      pass on to the socket itself.
 921  *
 922  *      NOTE: I like the idea of a module for the config stuff. ie ifconfig
 923  *      loads the devconfigure module does its configuring and unloads it.
 924  *      There's a good 20K of config code hanging around the kernel.
 925  */
 926
 927 int inet_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 928 {
 929         struct sock *sk = sock->sk;
 930         int err = 0;
 931         struct net *net = sock_net(sk);
 932         void __user *p = (void __user *)arg;
 933         struct ifreq ifr;
 934         struct rtentry rt;
 935
 936         switch (cmd) {
 937         case SIOCADDRT:
 938         case SIOCDELRT:
 939                 if (copy_from_user(&rt, p, sizeof(struct rtentry)))
 940                         return -EFAULT;
 941                 err = ip_rt_ioctl(net, cmd, &rt);
 942                 break;
 943         case SIOCRTMSG:
 944                 err = -EINVAL;
 945                 break;
 946         case SIOCDARP:
 947         case SIOCGARP:
 948         case SIOCSARP:
 949                 err = arp_ioctl(net, cmd, (void __user *)arg);
 950                 break;
 951         case SIOCGIFADDR:
 952         case SIOCGIFBRDADDR:
 953         case SIOCGIFNETMASK:
 954         case SIOCGIFDSTADDR:
 955         case SIOCGIFPFLAGS:
 956                 if (copy_from_user(&ifr, p, sizeof(struct ifreq)))
 957                         return -EFAULT;
 958                 err = devinet_ioctl(net, cmd, &ifr);
 959                 if (!err && copy_to_user(p, &ifr, sizeof(struct ifreq)))
 960                         err = -EFAULT;
 961                 break;
 962
 963         case SIOCSIFADDR:
 964         case SIOCSIFBRDADDR:
 965         case SIOCSIFNETMASK:
 966         case SIOCSIFDSTADDR:
 967         case SIOCSIFPFLAGS:
 968         case SIOCSIFFLAGS:
 969                 if (copy_from_user(&ifr, p, sizeof(struct ifreq)))
 970                         return -EFAULT;
 971                 err = devinet_ioctl(net, cmd, &ifr);
 972                 break;
 973         default:
 974                 if (sk->sk_prot->ioctl)
 975                         err = sk->sk_prot->ioctl(sk, cmd, arg);
 976                 else
 977                         err = -ENOIOCTLCMD;
 978                 break;
 979         }
 980         return err;
 981 }
 982 EXPORT_SYMBOL(inet_ioctl);
 983
 984 #ifdef CONFIG_COMPAT
 985 static int inet_compat_routing_ioctl(struct sock *sk, unsigned int cmd,
 986                 struct compat_rtentry __user *ur)
 987 {
 988         compat_uptr_t rtdev;
 989         struct rtentry rt;
 990
 991         if (copy_from_user(&rt.rt_dst, &ur->rt_dst,
 992                         3 * sizeof(struct sockaddr)) ||
 993             get_user(rt.rt_flags, &ur->rt_flags) ||
 994             get_user(rt.rt_metric, &ur->rt_metric) ||
 995             get_user(rt.rt_mtu, &ur->rt_mtu) ||
 996             get_user(rt.rt_window, &ur->rt_window) ||
 997             get_user(rt.rt_irtt, &ur->rt_irtt) ||
 998             get_user(rtdev, &ur->rt_dev))
 999                 return -EFAULT;
1000
1001         rt.rt_dev = compat_ptr(rtdev);
1002         return ip_rt_ioctl(sock_net(sk), cmd, &rt);
1003 }
1004
1005 static int inet_compat_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1006 {
1007         void __user *argp = compat_ptr(arg);
1008         struct sock *sk = sock->sk;
1009
1010         switch (cmd) {
1011         case SIOCADDRT:
1012         case SIOCDELRT:
1013                 return inet_compat_routing_ioctl(sk, cmd, argp);
1014         default:
1015                 if (!sk->sk_prot->compat_ioctl)
1016                         return -ENOIOCTLCMD;
1017                 return sk->sk_prot->compat_ioctl(sk, cmd, arg);
1018         }
1019 }
1020 #endif /* CONFIG_COMPAT */
1021
1022 const struct proto_ops inet_stream_ops = {
1023         .family            = PF_INET,
1024         .owner             = THIS_MODULE,
1025         .release           = inet_release,
1026         .bind              = inet_bind,
1027         .connect           = inet_stream_connect,
1028         .socketpair        = sock_no_socketpair,
1029         .accept            = inet_accept,
1030         .getname           = inet_getname,
1031         .poll              = tcp_poll,
1032         .ioctl             = inet_ioctl,
1033         .gettstamp         = sock_gettstamp,
1034         .listen            = inet_listen,
1035         .shutdown          = inet_shutdown,
1036         .setsockopt        = sock_common_setsockopt,
1037         .getsockopt        = sock_common_getsockopt,
1038         .sendmsg           = inet_sendmsg,
1039         .recvmsg           = inet_recvmsg,
1040 #ifdef CONFIG_MMU
1041         .mmap              = tcp_mmap,
1042 #endif
1043         .sendpage          = inet_sendpage,
1044         .splice_read       = tcp_splice_read,
1045         .read_sock         = tcp_read_sock,
1046         .sendmsg_locked    = tcp_sendmsg_locked,
1047         .sendpage_locked   = tcp_sendpage_locked,
1048         .peek_len          = tcp_peek_len,
1049 #ifdef CONFIG_COMPAT
1050         .compat_ioctl      = inet_compat_ioctl,
1051 #endif
1052         .set_rcvlowat      = tcp_set_rcvlowat,
1053 };
1054 EXPORT_SYMBOL(inet_stream_ops);
1055
1056 const struct proto_ops inet_dgram_ops = {
1057         .family            = PF_INET,
1058         .owner             = THIS_MODULE,
1059         .release           = inet_release,
1060         .bind              = inet_bind,
1061         .connect           = inet_dgram_connect,
1062         .socketpair        = sock_no_socketpair,
1063         .accept            = sock_no_accept,
1064         .getname           = inet_getname,
1065         .poll              = udp_poll,
1066         .ioctl             = inet_ioctl,
1067         .gettstamp         = sock_gettstamp,
1068         .listen            = sock_no_listen,
1069         .shutdown          = inet_shutdown,
1070         .setsockopt        = sock_common_setsockopt,
1071         .getsockopt        = sock_common_getsockopt,
1072         .sendmsg           = inet_sendmsg,
1073         .read_sock         = udp_read_sock,
1074         .recvmsg           = inet_recvmsg,
1075         .mmap              = sock_no_mmap,
1076         .sendpage          = inet_sendpage,
1077         .set_peek_off      = sk_set_peek_off,
1078 #ifdef CONFIG_COMPAT
1079         .compat_ioctl      = inet_compat_ioctl,
1080 #endif
1081 };
1082 EXPORT_SYMBOL(inet_dgram_ops);
1083
1084 /*
1085  * For SOCK_RAW sockets; should be the same as inet_dgram_ops but without
1086  * udp_poll
1087  */
1088 static const struct proto_ops inet_sockraw_ops = {
1089         .family            = PF_INET,
1090         .owner             = THIS_MODULE,
1091         .release           = inet_release,
1092         .bind              = inet_bind,
1093         .connect           = inet_dgram_connect,
1094         .socketpair        = sock_no_socketpair,
1095         .accept            = sock_no_accept,
1096         .getname           = inet_getname,
1097         .poll              = datagram_poll,
1098         .ioctl             = inet_ioctl,
1099         .gettstamp         = sock_gettstamp,
1100         .listen            = sock_no_listen,
1101         .shutdown          = inet_shutdown,
1102         .setsockopt        = sock_common_setsockopt,
1103         .getsockopt        = sock_common_getsockopt,
1104         .sendmsg           = inet_sendmsg,
1105         .recvmsg           = inet_recvmsg,
1106         .mmap              = sock_no_mmap,
1107         .sendpage          = inet_sendpage,
1108 #ifdef CONFIG_COMPAT
1109         .compat_ioctl      = inet_compat_ioctl,
1110 #endif
1111 };
1112
1113 static const struct net_proto_family inet_family_ops = {
1114         .family = PF_INET,
1115         .create = inet_create,
1116         .owner  = THIS_MODULE,
1117 };
1118
1119 /* Upon startup we insert all the elements in inetsw_array[] into
1120  * the linked list inetsw.
1121  */
1122 static struct inet_protosw inetsw_array[] =
1123 {
1124         {
1125                 .type =       SOCK_STREAM,
1126                 .protocol =   IPPROTO_TCP,
1127                 .prot =       &tcp_prot,
1128                 .ops =        &inet_stream_ops,
1129                 .flags =      INET_PROTOSW_PERMANENT |
1130                               INET_PROTOSW_ICSK,
1131         },
1132
1133         {
1134                 .type =       SOCK_DGRAM,
1135                 .protocol =   IPPROTO_UDP,
1136                 .prot =       &udp_prot,
1137                 .ops =        &inet_dgram_ops,
1138                 .flags =      INET_PROTOSW_PERMANENT,
1139        },
1140
1141        {
1142                 .type =       SOCK_DGRAM,
1143                 .protocol =   IPPROTO_ICMP,
1144                 .prot =       &ping_prot,
1145                 .ops =        &inet_sockraw_ops,
1146                 .flags =      INET_PROTOSW_REUSE,
1147        },
1148
1149        {
1150                .type =       SOCK_RAW,
1151                .protocol =   IPPROTO_IP,        /* wild card */
1152                .prot =       &raw_prot,
1153                .ops =        &inet_sockraw_ops,
1154                .flags =      INET_PROTOSW_REUSE,
1155        }
1156 };
1157
1158 #define INETSW_ARRAY_LEN ARRAY_SIZE(inetsw_array)
1159
1160 void inet_register_protosw(struct inet_protosw *p)
1161 {
1162         struct list_head *lh;
1163         struct inet_protosw *answer;
1164         int protocol = p->protocol;
1165         struct list_head *last_perm;
1166
1167         spin_lock_bh(&inetsw_lock);
1168
1169         if (p->type >= SOCK_MAX)
1170                 goto out_illegal;
1171
1172         /* If we are trying to override a permanent protocol, bail. */
1173         last_perm = &inetsw[p->type];
1174         list_for_each(lh, &inetsw[p->type]) {
1175                 answer = list_entry(lh, struct inet_protosw, list);
1176                 /* Check only the non-wild match. */
1177                 if ((INET_PROTOSW_PERMANENT & answer->flags) == 0)
1178                         break;
1179                 if (protocol == answer->protocol)
1180                         goto out_permanent;
1181                 last_perm = lh;
1182         }
1183
1184         /* Add the new entry after the last permanent entry if any, so that
1185          * the new entry does not override a permanent entry when matched with
1186          * a wild-card protocol. But it is allowed to override any existing
1187          * non-permanent entry.  This means that when we remove this entry, the
1188          * system automatically returns to the old behavior.
1189          */
1190         list_add_rcu(&p->list, last_perm);
1191 out:
1192         spin_unlock_bh(&inetsw_lock);
1193
1194         return;
1195
1196 out_permanent:
1197         pr_err("Attempt to override permanent protocol %d\n", protocol);
1198         goto out;
1199
1200 out_illegal:
1201         pr_err("Ignoring attempt to register invalid socket type %d\n",
1202                p->type);
1203         goto out;
1204 }
1205 EXPORT_SYMBOL(inet_register_protosw);
1206
1207 void inet_unregister_protosw(struct inet_protosw *p)
1208 {
1209         if (INET_PROTOSW_PERMANENT & p->flags) {
1210                 pr_err("Attempt to unregister permanent protocol %d\n",
1211                        p->protocol);
1212         } else {
1213                 spin_lock_bh(&inetsw_lock);
1214                 list_del_rcu(&p->list);
1215                 spin_unlock_bh(&inetsw_lock);
1216
1217                 synchronize_net();
1218         }
1219 }
1220 EXPORT_SYMBOL(inet_unregister_protosw);
1221
1222 static int inet_sk_reselect_saddr(struct sock *sk)
1223 {
1224         struct inet_sock *inet = inet_sk(sk);
1225         __be32 old_saddr = inet->inet_saddr;
1226         __be32 daddr = inet->inet_daddr;
1227         struct flowi4 *fl4;
1228         struct rtable *rt;
1229         __be32 new_saddr;
1230         struct ip_options_rcu *inet_opt;
1231
1232         inet_opt = rcu_dereference_protected(inet->inet_opt,
1233                                              lockdep_sock_is_held(sk));
1234         if (inet_opt && inet_opt->opt.srr)
1235                 daddr = inet_opt->opt.faddr;
1236
1237         /* Query new route. */
1238         fl4 = &inet->cork.fl.u.ip4;
1239         rt = ip_route_connect(fl4, daddr, 0, RT_CONN_FLAGS(sk),
1240                               sk->sk_bound_dev_if, sk->sk_protocol,
1241                               inet->inet_sport, inet->inet_dport, sk);
1242         if (IS_ERR(rt))
1243                 return PTR_ERR(rt);
1244
1245         sk_setup_caps(sk, &rt->dst);
1246
1247         new_saddr = fl4->saddr;
1248
1249         if (new_saddr == old_saddr)
1250                 return 0;
1251
1252         if (sock_net(sk)->ipv4.sysctl_ip_dynaddr > 1) {
1253                 pr_info("%s(): shifting inet->saddr from %pI4 to %pI4\n",
1254                         __func__, &old_saddr, &new_saddr);
1255         }
1256
1257         inet->inet_saddr = inet->inet_rcv_saddr = new_saddr;
1258
1259         /*
1260          * XXX The only one ugly spot where we need to
1261          * XXX really change the sockets identity after
1262          * XXX it has entered the hashes. -DaveM
1263          *
1264          * Besides that, it does not check for connection
1265          * uniqueness. Wait for troubles.
1266          */
1267         return __sk_prot_rehash(sk);
1268 }
1269
1270 int inet_sk_rebuild_header(struct sock *sk)
1271 {
1272         struct inet_sock *inet = inet_sk(sk);
1273         struct rtable *rt = (struct rtable *)__sk_dst_check(sk, 0);
1274         __be32 daddr;
1275         struct ip_options_rcu *inet_opt;
1276         struct flowi4 *fl4;
1277         int err;
1278
1279         /* Route is OK, nothing to do. */
1280         if (rt)
1281                 return 0;
1282
1283         /* Reroute. */
1284         rcu_read_lock();
1285         inet_opt = rcu_dereference(inet->inet_opt);
1286         daddr = inet->inet_daddr;
1287         if (inet_opt && inet_opt->opt.srr)
1288                 daddr = inet_opt->opt.faddr;
1289         rcu_read_unlock();
1290         fl4 = &inet->cork.fl.u.ip4;
1291         rt = ip_route_output_ports(sock_net(sk), fl4, sk, daddr, inet->inet_saddr,
1292                                    inet->inet_dport, inet->inet_sport,
1293                                    sk->sk_protocol, RT_CONN_FLAGS(sk),
1294                                    sk->sk_bound_dev_if);
1295         if (!IS_ERR(rt)) {
1296                 err = 0;
1297                 sk_setup_caps(sk, &rt->dst);
1298         } else {
1299                 err = PTR_ERR(rt);
1300
1301                 /* Routing failed... */
1302                 sk->sk_route_caps = 0;
1303                 /*
1304                  * Other protocols have to map its equivalent state to TCP_SYN_SENT.
1305                  * DCCP maps its DCCP_REQUESTING state to TCP_SYN_SENT. -acme
1306                  */
1307                 if (!sock_net(sk)->ipv4.sysctl_ip_dynaddr ||
1308                     sk->sk_state != TCP_SYN_SENT ||
1309                     (sk->sk_userlocks & SOCK_BINDADDR_LOCK) ||
1310                     (err = inet_sk_reselect_saddr(sk)) != 0)
1311                         sk->sk_err_soft = -err;
1312         }
1313
1314         return err;
1315 }
1316 EXPORT_SYMBOL(inet_sk_rebuild_header);
1317
1318 void inet_sk_set_state(struct sock *sk, int state)
1319 {
1320         trace_inet_sock_set_state(sk, sk->sk_state, state);
1321         sk->sk_state = state;
1322 }
1323 EXPORT_SYMBOL(inet_sk_set_state);
1324
1325 void inet_sk_state_store(struct sock *sk, int newstate)
1326 {
1327         trace_inet_sock_set_state(sk, sk->sk_state, newstate);
1328         smp_store_release(&sk->sk_state, newstate);
1329 }
1330
1331 struct sk_buff *inet_gso_segment(struct sk_buff *skb,
1332                                  netdev_features_t features)
1333 {
1334         bool udpfrag = false, fixedid = false, gso_partial, encap;
1335         struct sk_buff *segs = ERR_PTR(-EINVAL);
1336         const struct net_offload *ops;
1337         unsigned int offset = 0;
1338         struct iphdr *iph;
1339         int proto, tot_len;
1340         int nhoff;
1341         int ihl;
1342         int id;
1343
1344         skb_reset_network_header(skb);
1345         nhoff = skb_network_header(skb) - skb_mac_header(skb);
1346         if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
1347                 goto out;
1348
1349         iph = ip_hdr(skb);
1350         ihl = iph->ihl * 4;
1351         if (ihl < sizeof(*iph))
1352                 goto out;
1353
1354         id = ntohs(iph->id);
1355         proto = iph->protocol;
1356
1357         /* Warning: after this point, iph might be no longer valid */
1358         if (unlikely(!pskb_may_pull(skb, ihl)))
1359                 goto out;
1360         __skb_pull(skb, ihl);
1361
1362         encap = SKB_GSO_CB(skb)->encap_level > 0;
1363         if (encap)
1364                 features &= skb->dev->hw_enc_features;
1365         SKB_GSO_CB(skb)->encap_level += ihl;
1366
1367         skb_reset_transport_header(skb);
1368
1369         segs = ERR_PTR(-EPROTONOSUPPORT);
1370
1371         if (!skb->encapsulation || encap) {
1372                 udpfrag = !!(skb_shinfo(skb)->gso_type & SKB_GSO_UDP);
1373                 fixedid = !!(skb_shinfo(skb)->gso_type & SKB_GSO_TCP_FIXEDID);
1374
1375                 /* fixed ID is invalid if DF bit is not set */
1376                 if (fixedid && !(ip_hdr(skb)->frag_off & htons(IP_DF)))
1377                         goto out;
1378         }
1379
1380         ops = rcu_dereference(inet_offloads[proto]);
1381         if (likely(ops && ops->callbacks.gso_segment))
1382                 segs = ops->callbacks.gso_segment(skb, features);
1383
1384         if (IS_ERR_OR_NULL(segs))
1385                 goto out;
1386
1387         gso_partial = !!(skb_shinfo(segs)->gso_type & SKB_GSO_PARTIAL);
1388
1389         skb = segs;
1390         do {
1391                 iph = (struct iphdr *)(skb_mac_header(skb) + nhoff);
1392                 if (udpfrag) {
1393                         iph->frag_off = htons(offset >> 3);
1394                         if (skb->next)
1395                                 iph->frag_off |= htons(IP_MF);
1396                         offset += skb->len - nhoff - ihl;
1397                         tot_len = skb->len - nhoff;
1398                 } else if (skb_is_gso(skb)) {
1399                         if (!fixedid) {
1400                                 iph->id = htons(id);
1401                                 id += skb_shinfo(skb)->gso_segs;
1402                         }
1403
1404                         if (gso_partial)
1405                                 tot_len = skb_shinfo(skb)->gso_size +
1406                                           SKB_GSO_CB(skb)->data_offset +
1407                                           skb->head - (unsigned char *)iph;
1408                         else
1409                                 tot_len = skb->len - nhoff;
1410                 } else {
1411                         if (!fixedid)
1412                                 iph->id = htons(id++);
1413                         tot_len = skb->len - nhoff;
1414                 }
1415                 iph->tot_len = htons(tot_len);
1416                 ip_send_check(iph);
1417                 if (encap)
1418                         skb_reset_inner_headers(skb);
1419                 skb->network_header = (u8 *)iph - skb->head;
1420                 skb_reset_mac_len(skb);
1421         } while ((skb = skb->next));
1422
1423 out:
1424         return segs;
1425 }
1426
1427 static struct sk_buff *ipip_gso_segment(struct sk_buff *skb,
1428                                         netdev_features_t features)
1429 {
1430         if (!(skb_shinfo(skb)->gso_type & SKB_GSO_IPXIP4))
1431                 return ERR_PTR(-EINVAL);
1432
1433         return inet_gso_segment(skb, features);
1434 }
1435
1436 struct sk_buff *inet_gro_receive(struct list_head *head, struct sk_buff *skb)
1437 {
1438         const struct net_offload *ops;
1439         struct sk_buff *pp = NULL;
1440         const struct iphdr *iph;
1441         struct sk_buff *p;
1442         unsigned int hlen;
1443         unsigned int off;
1444         unsigned int id;
1445         int flush = 1;
1446         int proto;
1447
1448         off = skb_gro_offset(skb);
1449         hlen = off + sizeof(*iph);
1450         iph = skb_gro_header_fast(skb, off);
1451         if (skb_gro_header_hard(skb, hlen)) {
1452                 iph = skb_gro_header_slow(skb, hlen, off);
1453                 if (unlikely(!iph))
1454                         goto out;
1455         }
1456
1457         proto = iph->protocol;
1458
1459         rcu_read_lock();
1460         ops = rcu_dereference(inet_offloads[proto]);
1461         if (!ops || !ops->callbacks.gro_receive)
1462                 goto out_unlock;
1463
1464         if (*(u8 *)iph != 0x45)
1465                 goto out_unlock;
1466
1467         if (ip_is_fragment(iph))
1468                 goto out_unlock;
1469
1470         if (unlikely(ip_fast_csum((u8 *)iph, 5)))
1471                 goto out_unlock;
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_unlock:
1549         rcu_read_unlock();
1550
1551 out:
1552         skb_gro_flush_final(skb, pp, flush);
1553
1554         return pp;
1555 }
1556
1557 static struct sk_buff *ipip_gro_receive(struct list_head *head,
1558                                         struct sk_buff *skb)
1559 {
1560         if (NAPI_GRO_CB(skb)->encap_mark) {
1561                 NAPI_GRO_CB(skb)->flush = 1;
1562                 return NULL;
1563         }
1564
1565         NAPI_GRO_CB(skb)->encap_mark = 1;
1566
1567         return inet_gro_receive(head, skb);
1568 }
1569
1570 #define SECONDS_PER_DAY 86400
1571
1572 /* inet_current_timestamp - Return IP network timestamp
1573  *
1574  * Return milliseconds since midnight in network byte order.
1575  */
1576 __be32 inet_current_timestamp(void)
1577 {
1578         u32 secs;
1579         u32 msecs;
1580         struct timespec64 ts;
1581
1582         ktime_get_real_ts64(&ts);
1583
1584         /* Get secs since midnight. */
1585         (void)div_u64_rem(ts.tv_sec, SECONDS_PER_DAY, &secs);
1586         /* Convert to msecs. */
1587         msecs = secs * MSEC_PER_SEC;
1588         /* Convert nsec to msec. */
1589         msecs += (u32)ts.tv_nsec / NSEC_PER_MSEC;
1590
1591         /* Convert to network byte order. */
1592         return htonl(msecs);
1593 }
1594 EXPORT_SYMBOL(inet_current_timestamp);
1595
1596 int inet_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
1597 {
1598         if (sk->sk_family == AF_INET)
1599                 return ip_recv_error(sk, msg, len, addr_len);
1600 #if IS_ENABLED(CONFIG_IPV6)
1601         if (sk->sk_family == AF_INET6)
1602                 return pingv6_ops.ipv6_recv_error(sk, msg, len, addr_len);
1603 #endif
1604         return -EINVAL;
1605 }
1606
1607 int inet_gro_complete(struct sk_buff *skb, int nhoff)
1608 {
1609         __be16 newlen = htons(skb->len - nhoff);
1610         struct iphdr *iph = (struct iphdr *)(skb->data + nhoff);
1611         const struct net_offload *ops;
1612         int proto = iph->protocol;
1613         int err = -ENOSYS;
1614
1615         if (skb->encapsulation) {
1616                 skb_set_inner_protocol(skb, cpu_to_be16(ETH_P_IP));
1617                 skb_set_inner_network_header(skb, nhoff);
1618         }
1619
1620         csum_replace2(&iph->check, iph->tot_len, newlen);
1621         iph->tot_len = newlen;
1622
1623         rcu_read_lock();
1624         ops = rcu_dereference(inet_offloads[proto]);
1625         if (WARN_ON(!ops || !ops->callbacks.gro_complete))
1626                 goto out_unlock;
1627
1628         /* Only need to add sizeof(*iph) to get to the next hdr below
1629          * because any hdr with option will have been flushed in
1630          * inet_gro_receive().
1631          */
1632         err = INDIRECT_CALL_2(ops->callbacks.gro_complete,
1633                               tcp4_gro_complete, udp4_gro_complete,
1634                               skb, nhoff + sizeof(*iph));
1635
1636 out_unlock:
1637         rcu_read_unlock();
1638
1639         return err;
1640 }
1641
1642 static int ipip_gro_complete(struct sk_buff *skb, int nhoff)
1643 {
1644         skb->encapsulation = 1;
1645         skb_shinfo(skb)->gso_type |= SKB_GSO_IPXIP4;
1646         return inet_gro_complete(skb, nhoff);
1647 }
1648
1649 int inet_ctl_sock_create(struct sock **sk, unsigned short family,
1650                          unsigned short type, unsigned char protocol,
1651                          struct net *net)
1652 {
1653         struct socket *sock;
1654         int rc = sock_create_kern(net, family, type, protocol, &sock);
1655
1656         if (rc == 0) {
1657                 *sk = sock->sk;
1658                 (*sk)->sk_allocation = GFP_ATOMIC;
1659                 /*
1660                  * Unhash it so that IP input processing does not even see it,
1661                  * we do not wish this socket to see incoming packets.
1662                  */
1663                 (*sk)->sk_prot->unhash(*sk);
1664         }
1665         return rc;
1666 }
1667 EXPORT_SYMBOL_GPL(inet_ctl_sock_create);
1668
1669 u64 snmp_get_cpu_field(void __percpu *mib, int cpu, int offt)
1670 {
1671         return  *(((unsigned long *)per_cpu_ptr(mib, cpu)) + offt);
1672 }
1673 EXPORT_SYMBOL_GPL(snmp_get_cpu_field);
1674
1675 unsigned long snmp_fold_field(void __percpu *mib, int offt)
1676 {
1677         unsigned long res = 0;
1678         int i;
1679
1680         for_each_possible_cpu(i)
1681                 res += snmp_get_cpu_field(mib, i, offt);
1682         return res;
1683 }
1684 EXPORT_SYMBOL_GPL(snmp_fold_field);
1685
1686 #if BITS_PER_LONG==32
1687
1688 u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offt,
1689                          size_t syncp_offset)
1690 {
1691         void *bhptr;
1692         struct u64_stats_sync *syncp;
1693         u64 v;
1694         unsigned int start;
1695
1696         bhptr = per_cpu_ptr(mib, cpu);
1697         syncp = (struct u64_stats_sync *)(bhptr + syncp_offset);
1698         do {
1699                 start = u64_stats_fetch_begin_irq(syncp);
1700                 v = *(((u64 *)bhptr) + offt);
1701         } while (u64_stats_fetch_retry_irq(syncp, start));
1702
1703         return v;
1704 }
1705 EXPORT_SYMBOL_GPL(snmp_get_cpu_field64);
1706
1707 u64 snmp_fold_field64(void __percpu *mib, int offt, size_t syncp_offset)
1708 {
1709         u64 res = 0;
1710         int cpu;
1711
1712         for_each_possible_cpu(cpu) {
1713                 res += snmp_get_cpu_field64(mib, cpu, offt, syncp_offset);
1714         }
1715         return res;
1716 }
1717 EXPORT_SYMBOL_GPL(snmp_fold_field64);
1718 #endif
1719
1720 #ifdef CONFIG_IP_MULTICAST
1721 static const struct net_protocol igmp_protocol = {
1722         .handler =      igmp_rcv,
1723         .netns_ok =     1,
1724 };
1725 #endif
1726
1727 /* thinking of making this const? Don't.
1728  * early_demux can change based on sysctl.
1729  */
1730 static struct net_protocol tcp_protocol = {
1731         .early_demux    =       tcp_v4_early_demux,
1732         .early_demux_handler =  tcp_v4_early_demux,
1733         .handler        =       tcp_v4_rcv,
1734         .err_handler    =       tcp_v4_err,
1735         .no_policy      =       1,
1736         .netns_ok       =       1,
1737         .icmp_strict_tag_validation = 1,
1738 };
1739
1740 /* thinking of making this const? Don't.
1741  * early_demux can change based on sysctl.
1742  */
1743 static struct net_protocol udp_protocol = {
1744         .early_demux =  udp_v4_early_demux,
1745         .early_demux_handler =  udp_v4_early_demux,
1746         .handler =      udp_rcv,
1747         .err_handler =  udp_err,
1748         .no_policy =    1,
1749         .netns_ok =     1,
1750 };
1751
1752 static const struct net_protocol icmp_protocol = {
1753         .handler =      icmp_rcv,
1754         .err_handler =  icmp_err,
1755         .no_policy =    1,
1756         .netns_ok =     1,
1757 };
1758
1759 static __net_init int ipv4_mib_init_net(struct net *net)
1760 {
1761         int i;
1762
1763         net->mib.tcp_statistics = alloc_percpu(struct tcp_mib);
1764         if (!net->mib.tcp_statistics)
1765                 goto err_tcp_mib;
1766         net->mib.ip_statistics = alloc_percpu(struct ipstats_mib);
1767         if (!net->mib.ip_statistics)
1768                 goto err_ip_mib;
1769
1770         for_each_possible_cpu(i) {
1771                 struct ipstats_mib *af_inet_stats;
1772                 af_inet_stats = per_cpu_ptr(net->mib.ip_statistics, i);
1773                 u64_stats_init(&af_inet_stats->syncp);
1774         }
1775
1776         net->mib.net_statistics = alloc_percpu(struct linux_mib);
1777         if (!net->mib.net_statistics)
1778                 goto err_net_mib;
1779         net->mib.udp_statistics = alloc_percpu(struct udp_mib);
1780         if (!net->mib.udp_statistics)
1781                 goto err_udp_mib;
1782         net->mib.udplite_statistics = alloc_percpu(struct udp_mib);
1783         if (!net->mib.udplite_statistics)
1784                 goto err_udplite_mib;
1785         net->mib.icmp_statistics = alloc_percpu(struct icmp_mib);
1786         if (!net->mib.icmp_statistics)
1787                 goto err_icmp_mib;
1788         net->mib.icmpmsg_statistics = kzalloc(sizeof(struct icmpmsg_mib),
1789                                               GFP_KERNEL);
1790         if (!net->mib.icmpmsg_statistics)
1791                 goto err_icmpmsg_mib;
1792
1793         tcp_mib_init(net);
1794         return 0;
1795
1796 err_icmpmsg_mib:
1797         free_percpu(net->mib.icmp_statistics);
1798 err_icmp_mib:
1799         free_percpu(net->mib.udplite_statistics);
1800 err_udplite_mib:
1801         free_percpu(net->mib.udp_statistics);
1802 err_udp_mib:
1803         free_percpu(net->mib.net_statistics);
1804 err_net_mib:
1805         free_percpu(net->mib.ip_statistics);
1806 err_ip_mib:
1807         free_percpu(net->mib.tcp_statistics);
1808 err_tcp_mib:
1809         return -ENOMEM;
1810 }
1811
1812 static __net_exit void ipv4_mib_exit_net(struct net *net)
1813 {
1814         kfree(net->mib.icmpmsg_statistics);
1815         free_percpu(net->mib.icmp_statistics);
1816         free_percpu(net->mib.udplite_statistics);
1817         free_percpu(net->mib.udp_statistics);
1818         free_percpu(net->mib.net_statistics);
1819         free_percpu(net->mib.ip_statistics);
1820         free_percpu(net->mib.tcp_statistics);
1821 #ifdef CONFIG_MPTCP
1822         /* allocated on demand, see mptcp_init_sock() */
1823         free_percpu(net->mib.mptcp_statistics);
1824 #endif
1825 }
1826
1827 static __net_initdata struct pernet_operations ipv4_mib_ops = {
1828         .init = ipv4_mib_init_net,
1829         .exit = ipv4_mib_exit_net,
1830 };
1831
1832 static int __init init_ipv4_mibs(void)
1833 {
1834         return register_pernet_subsys(&ipv4_mib_ops);
1835 }
1836
1837 static __net_init int inet_init_net(struct net *net)
1838 {
1839         /*
1840          * Set defaults for local port range
1841          */
1842         seqlock_init(&net->ipv4.ip_local_ports.lock);
1843         net->ipv4.ip_local_ports.range[0] =  32768;
1844         net->ipv4.ip_local_ports.range[1] =  60999;
1845
1846         seqlock_init(&net->ipv4.ping_group_range.lock);
1847         /*
1848          * Sane defaults - nobody may create ping sockets.
1849          * Boot scripts should set this to distro-specific group.
1850          */
1851         net->ipv4.ping_group_range.range[0] = make_kgid(&init_user_ns, 1);
1852         net->ipv4.ping_group_range.range[1] = make_kgid(&init_user_ns, 0);
1853
1854         /* Default values for sysctl-controlled parameters.
1855          * We set them here, in case sysctl is not compiled.
1856          */
1857         net->ipv4.sysctl_ip_default_ttl = IPDEFTTL;
1858         net->ipv4.sysctl_ip_fwd_update_priority = 1;
1859         net->ipv4.sysctl_ip_dynaddr = 0;
1860         net->ipv4.sysctl_ip_early_demux = 1;
1861         net->ipv4.sysctl_udp_early_demux = 1;
1862         net->ipv4.sysctl_tcp_early_demux = 1;
1863         net->ipv4.sysctl_nexthop_compat_mode = 1;
1864 #ifdef CONFIG_SYSCTL
1865         net->ipv4.sysctl_ip_prot_sock = PROT_SOCK;
1866 #endif
1867
1868         /* Some igmp sysctl, whose values are always used */
1869         net->ipv4.sysctl_igmp_max_memberships = 20;
1870         net->ipv4.sysctl_igmp_max_msf = 10;
1871         /* IGMP reports for link-local multicast groups are enabled by default */
1872         net->ipv4.sysctl_igmp_llm_reports = 1;
1873         net->ipv4.sysctl_igmp_qrv = 2;
1874
1875         net->ipv4.sysctl_fib_notify_on_flag_change = 0;
1876
1877         return 0;
1878 }
1879
1880 static __net_initdata struct pernet_operations af_inet_ops = {
1881         .init = inet_init_net,
1882 };
1883
1884 static int __init init_inet_pernet_ops(void)
1885 {
1886         return register_pernet_subsys(&af_inet_ops);
1887 }
1888
1889 static int ipv4_proc_init(void);
1890
1891 /*
1892  *      IP protocol layer initialiser
1893  */
1894
1895 static struct packet_offload ip_packet_offload __read_mostly = {
1896         .type = cpu_to_be16(ETH_P_IP),
1897         .callbacks = {
1898                 .gso_segment = inet_gso_segment,
1899                 .gro_receive = inet_gro_receive,
1900                 .gro_complete = inet_gro_complete,
1901         },
1902 };
1903
1904 static const struct net_offload ipip_offload = {
1905         .callbacks = {
1906                 .gso_segment    = ipip_gso_segment,
1907                 .gro_receive    = ipip_gro_receive,
1908                 .gro_complete   = ipip_gro_complete,
1909         },
1910 };
1911
1912 static int __init ipip_offload_init(void)
1913 {
1914         return inet_add_offload(&ipip_offload, IPPROTO_IPIP);
1915 }
1916
1917 static int __init ipv4_offload_init(void)
1918 {
1919         /*
1920          * Add offloads
1921          */
1922         if (udpv4_offload_init() < 0)
1923                 pr_crit("%s: Cannot add UDP protocol offload\n", __func__);
1924         if (tcpv4_offload_init() < 0)
1925                 pr_crit("%s: Cannot add TCP protocol offload\n", __func__);
1926         if (ipip_offload_init() < 0)
1927                 pr_crit("%s: Cannot add IPIP protocol offload\n", __func__);
1928
1929         dev_add_offload(&ip_packet_offload);
1930         return 0;
1931 }
1932
1933 fs_initcall(ipv4_offload_init);
1934
1935 static struct packet_type ip_packet_type __read_mostly = {
1936         .type = cpu_to_be16(ETH_P_IP),
1937         .func = ip_rcv,
1938         .list_func = ip_list_rcv,
1939 };
1940
1941 static int __init inet_init(void)
1942 {
1943         struct inet_protosw *q;
1944         struct list_head *r;
1945         int rc;
1946
1947         sock_skb_cb_check_size(sizeof(struct inet_skb_parm));
1948
1949         rc = proto_register(&tcp_prot, 1);
1950         if (rc)
1951                 goto out;
1952
1953         rc = proto_register(&udp_prot, 1);
1954         if (rc)
1955                 goto out_unregister_tcp_proto;
1956
1957         rc = proto_register(&raw_prot, 1);
1958         if (rc)
1959                 goto out_unregister_udp_proto;
1960
1961         rc = proto_register(&ping_prot, 1);
1962         if (rc)
1963                 goto out_unregister_raw_proto;
1964
1965         /*
1966          *      Tell SOCKET that we are alive...
1967          */
1968
1969         (void)sock_register(&inet_family_ops);
1970
1971 #ifdef CONFIG_SYSCTL
1972         ip_static_sysctl_init();
1973 #endif
1974
1975         /*
1976          *      Add all the base protocols.
1977          */
1978
1979         if (inet_add_protocol(&icmp_protocol, IPPROTO_ICMP) < 0)
1980                 pr_crit("%s: Cannot add ICMP protocol\n", __func__);
1981         if (inet_add_protocol(&udp_protocol, IPPROTO_UDP) < 0)
1982                 pr_crit("%s: Cannot add UDP protocol\n", __func__);
1983         if (inet_add_protocol(&tcp_protocol, IPPROTO_TCP) < 0)
1984                 pr_crit("%s: Cannot add TCP protocol\n", __func__);
1985 #ifdef CONFIG_IP_MULTICAST
1986         if (inet_add_protocol(&igmp_protocol, IPPROTO_IGMP) < 0)
1987                 pr_crit("%s: Cannot add IGMP protocol\n", __func__);
1988 #endif
1989
1990         /* Register the socket-side information for inet_create. */
1991         for (r = &inetsw[0]; r < &inetsw[SOCK_MAX]; ++r)
1992                 INIT_LIST_HEAD(r);
1993
1994         for (q = inetsw_array; q < &inetsw_array[INETSW_ARRAY_LEN]; ++q)
1995                 inet_register_protosw(q);
1996
1997         /*
1998          *      Set the ARP module up
1999          */
2000
2001         arp_init();
2002
2003         /*
2004          *      Set the IP module up
2005          */
2006
2007         ip_init();
2008
2009         /* Setup TCP slab cache for open requests. */
2010         tcp_init();
2011
2012         /* Setup UDP memory threshold */
2013         udp_init();
2014
2015         /* Add UDP-Lite (RFC 3828) */
2016         udplite4_register();
2017
2018         raw_init();
2019
2020         ping_init();
2021
2022         /*
2023          *      Set the ICMP layer up
2024          */
2025
2026         if (icmp_init() < 0)
2027                 panic("Failed to create the ICMP control socket.\n");
2028
2029         /*
2030          *      Initialise the multicast router
2031          */
2032 #if defined(CONFIG_IP_MROUTE)
2033         if (ip_mr_init())
2034                 pr_crit("%s: Cannot init ipv4 mroute\n", __func__);
2035 #endif
2036
2037         if (init_inet_pernet_ops())
2038                 pr_crit("%s: Cannot init ipv4 inet pernet ops\n", __func__);
2039         /*
2040          *      Initialise per-cpu ipv4 mibs
2041          */
2042
2043         if (init_ipv4_mibs())
2044                 pr_crit("%s: Cannot init ipv4 mibs\n", __func__);
2045
2046         ipv4_proc_init();
2047
2048         ipfrag_init();
2049
2050         dev_add_pack(&ip_packet_type);
2051
2052         ip_tunnel_core_init();
2053
2054         rc = 0;
2055 out:
2056         return rc;
2057 out_unregister_raw_proto:
2058         proto_unregister(&raw_prot);
2059 out_unregister_udp_proto:
2060         proto_unregister(&udp_prot);
2061 out_unregister_tcp_proto:
2062         proto_unregister(&tcp_prot);
2063         goto out;
2064 }
2065
2066 fs_initcall(inet_init);
2067
2068 /* ------------------------------------------------------------------------ */
2069
2070 #ifdef CONFIG_PROC_FS
2071 static int __init ipv4_proc_init(void)
2072 {
2073         int rc = 0;
2074
2075         if (raw_proc_init())
2076                 goto out_raw;
2077         if (tcp4_proc_init())
2078                 goto out_tcp;
2079         if (udp4_proc_init())
2080                 goto out_udp;
2081         if (ping_proc_init())
2082                 goto out_ping;
2083         if (ip_misc_proc_init())
2084                 goto out_misc;
2085 out:
2086         return rc;
2087 out_misc:
2088         ping_proc_exit();
2089 out_ping:
2090         udp4_proc_exit();
2091 out_udp:
2092         tcp4_proc_exit();
2093 out_tcp:
2094         raw_proc_exit();
2095 out_raw:
2096         rc = -ENOMEM;
2097         goto out;
2098 }
2099
2100 #else /* CONFIG_PROC_FS */
2101 static int __init ipv4_proc_init(void)
2102 {
2103         return 0;
2104 }
2105 #endif /* CONFIG_PROC_FS */