1 /* 2 * INET An implementation of the TCP/IP protocol suite for the LINUX 3 * operating system. INET is implemented using the BSD Socket 4 * interface as the means of communication with the user level. 5 * 6 * PF_INET protocol family socket handler. 7 * 8 * Authors: Ross Biro 9 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 10 * Florian La Roche, <flla@stud.uni-sb.de> 11 * Alan Cox, <A.Cox@swansea.ac.uk> 12 * 13 * Changes (see also sock.c) 14 * 15 * piggy, 16 * Karl Knutson : Socket protocol table 17 * A.N.Kuznetsov : Socket death error in accept(). 18 * John Richardson : Fix non blocking error in connect() 19 * so sockets that fail to connect 20 * don't return -EINPROGRESS. 21 * Alan Cox : Asynchronous I/O support 22 * Alan Cox : Keep correct socket pointer on sock 23 * structures 24 * when accept() ed 25 * Alan Cox : Semantics of SO_LINGER aren't state 26 * moved to close when you look carefully. 27 * With this fixed and the accept bug fixed 28 * some RPC stuff seems happier. 29 * Niibe Yutaka : 4.4BSD style write async I/O 30 * Alan Cox, 31 * Tony Gale : Fixed reuse semantics. 32 * Alan Cox : bind() shouldn't abort existing but dead 33 * sockets. Stops FTP netin:.. I hope. 34 * Alan Cox : bind() works correctly for RAW sockets. 35 * Note that FreeBSD at least was broken 36 * in this respect so be careful with 37 * compatibility tests... 38 * Alan Cox : routing cache support 39 * Alan Cox : memzero the socket structure for 40 * compactness. 41 * Matt Day : nonblock connect error handler 42 * Alan Cox : Allow large numbers of pending sockets 43 * (eg for big web sites), but only if 44 * specifically application requested. 45 * Alan Cox : New buffering throughout IP. Used 46 * dumbly. 47 * Alan Cox : New buffering now used smartly. 48 * Alan Cox : BSD rather than common sense 49 * interpretation of listen. 50 * Germano Caronni : Assorted small races. 51 * Alan Cox : sendmsg/recvmsg basic support. 52 * Alan Cox : Only sendmsg/recvmsg now supported. 53 * Alan Cox : Locked down bind (see security list). 54 * Alan Cox : Loosened bind a little. 55 * Mike McLagan : ADD/DEL DLCI Ioctls 56 * Willy Konynenberg : Transparent proxying support. 57 * David S. Miller : New socket lookup architecture. 58 * Some other random speedups. 59 * Cyrus Durgin : Cleaned up file for kmod hacks. 60 * Andi Kleen : Fix inet_stream_connect TCP race. 61 * 62 * This program is free software; you can redistribute it and/or 63 * modify it under the terms of the GNU General Public License 64 * as published by the Free Software Foundation; either version 65 * 2 of the License, or (at your option) any later version. 66 */ 67 68 #define pr_fmt(fmt) "IPv4: " fmt 69 70 #include <linux/err.h> 71 #include <linux/errno.h> 72 #include <linux/types.h> 73 #include <linux/socket.h> 74 #include <linux/in.h> 75 #include <linux/kernel.h> 76 #include <linux/module.h> 77 #include <linux/sched.h> 78 #include <linux/timer.h> 79 #include <linux/string.h> 80 #include <linux/sockios.h> 81 #include <linux/net.h> 82 #include <linux/capability.h> 83 #include <linux/fcntl.h> 84 #include <linux/mm.h> 85 #include <linux/interrupt.h> 86 #include <linux/stat.h> 87 #include <linux/init.h> 88 #include <linux/poll.h> 89 #include <linux/netfilter_ipv4.h> 90 #include <linux/random.h> 91 #include <linux/slab.h> 92 93 #include <asm/uaccess.h> 94 95 #include <linux/inet.h> 96 #include <linux/igmp.h> 97 #include <linux/inetdevice.h> 98 #include <linux/netdevice.h> 99 #include <net/checksum.h> 100 #include <net/ip.h> 101 #include <net/protocol.h> 102 #include <net/arp.h> 103 #include <net/route.h> 104 #include <net/ip_fib.h> 105 #include <net/inet_connection_sock.h> 106 #include <net/tcp.h> 107 #include <net/udp.h> 108 #include <net/udplite.h> 109 #include <net/ping.h> 110 #include <linux/skbuff.h> 111 #include <net/sock.h> 112 #include <net/raw.h> 113 #include <net/icmp.h> 114 #include <net/inet_common.h> 115 #include <net/ip_tunnels.h> 116 #include <net/xfrm.h> 117 #include <net/net_namespace.h> 118 #include <net/secure_seq.h> 119 #ifdef CONFIG_IP_MROUTE 120 #include <linux/mroute.h> 121 #endif 122 #include <net/l3mdev.h> 123 124 125 /* The inetsw table contains everything that inet_create needs to 126 * build a new socket. 127 */ 128 static struct list_head inetsw[SOCK_MAX]; 129 static DEFINE_SPINLOCK(inetsw_lock); 130 131 /* New destruction routine */ 132 133 void inet_sock_destruct(struct sock *sk) 134 { 135 struct inet_sock *inet = inet_sk(sk); 136 137 __skb_queue_purge(&sk->sk_receive_queue); 138 __skb_queue_purge(&sk->sk_error_queue); 139 140 sk_mem_reclaim(sk); 141 142 if (sk->sk_type == SOCK_STREAM && sk->sk_state != TCP_CLOSE) { 143 pr_err("Attempt to release TCP socket in state %d %p\n", 144 sk->sk_state, sk); 145 return; 146 } 147 if (!sock_flag(sk, SOCK_DEAD)) { 148 pr_err("Attempt to release alive inet socket %p\n", sk); 149 return; 150 } 151 152 WARN_ON(atomic_read(&sk->sk_rmem_alloc)); 153 WARN_ON(atomic_read(&sk->sk_wmem_alloc)); 154 WARN_ON(sk->sk_wmem_queued); 155 WARN_ON(sk->sk_forward_alloc); 156 157 kfree(rcu_dereference_protected(inet->inet_opt, 1)); 158 dst_release(rcu_dereference_check(sk->sk_dst_cache, 1)); 159 dst_release(sk->sk_rx_dst); 160 sk_refcnt_debug_dec(sk); 161 } 162 EXPORT_SYMBOL(inet_sock_destruct); 163 164 /* 165 * The routines beyond this point handle the behaviour of an AF_INET 166 * socket object. Mostly it punts to the subprotocols of IP to do 167 * the work. 168 */ 169 170 /* 171 * Automatically bind an unbound socket. 172 */ 173 174 static int inet_autobind(struct sock *sk) 175 { 176 struct inet_sock *inet; 177 /* We may need to bind the socket. */ 178 lock_sock(sk); 179 inet = inet_sk(sk); 180 if (!inet->inet_num) { 181 if (sk->sk_prot->get_port(sk, 0)) { 182 release_sock(sk); 183 return -EAGAIN; 184 } 185 inet->inet_sport = htons(inet->inet_num); 186 } 187 release_sock(sk); 188 return 0; 189 } 190 191 /* 192 * Move a socket into listening state. 193 */ 194 int inet_listen(struct socket *sock, int backlog) 195 { 196 struct sock *sk = sock->sk; 197 unsigned char old_state; 198 int err; 199 200 lock_sock(sk); 201 202 err = -EINVAL; 203 if (sock->state != SS_UNCONNECTED || sock->type != SOCK_STREAM) 204 goto out; 205 206 old_state = sk->sk_state; 207 if (!((1 << old_state) & (TCPF_CLOSE | TCPF_LISTEN))) 208 goto out; 209 210 /* 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 /* Check special setups for testing purpose to enable TFO w/o 215 * requiring TCP_FASTOPEN sockopt. 216 * Note that only TCP sockets (SOCK_STREAM) will reach here. 217 * Also fastopenq may already been allocated because this 218 * socket was in TCP_LISTEN state previously but was 219 * shutdown() (rather than close()). 220 */ 221 if ((sysctl_tcp_fastopen & TFO_SERVER_ENABLE) != 0 && 222 !inet_csk(sk)->icsk_accept_queue.fastopenq.max_qlen) { 223 if ((sysctl_tcp_fastopen & TFO_SERVER_WO_SOCKOPT1) != 0) 224 fastopen_queue_tune(sk, backlog); 225 else if ((sysctl_tcp_fastopen & 226 TFO_SERVER_WO_SOCKOPT2) != 0) 227 fastopen_queue_tune(sk, 228 ((uint)sysctl_tcp_fastopen) >> 16); 229 230 tcp_fastopen_init_key_once(true); 231 } 232 err = inet_csk_listen_start(sk, backlog); 233 if (err) 234 goto out; 235 } 236 sk->sk_max_ack_backlog = backlog; 237 err = 0; 238 239 out: 240 release_sock(sk); 241 return err; 242 } 243 EXPORT_SYMBOL(inet_listen); 244 245 /* 246 * Create an inet socket. 247 */ 248 249 static int inet_create(struct net *net, struct socket *sock, int protocol, 250 int kern) 251 { 252 struct sock *sk; 253 struct inet_protosw *answer; 254 struct inet_sock *inet; 255 struct proto *answer_prot; 256 unsigned char answer_flags; 257 int try_loading_module = 0; 258 int err; 259 260 if (protocol < 0 || protocol >= IPPROTO_MAX) 261 return -EINVAL; 262 263 sock->state = SS_UNCONNECTED; 264 265 /* Look for the requested type/protocol pair. */ 266 lookup_protocol: 267 err = -ESOCKTNOSUPPORT; 268 rcu_read_lock(); 269 list_for_each_entry_rcu(answer, &inetsw[sock->type], list) { 270 271 err = 0; 272 /* Check the non-wild match. */ 273 if (protocol == answer->protocol) { 274 if (protocol != IPPROTO_IP) 275 break; 276 } else { 277 /* Check for the two wild cases. */ 278 if (IPPROTO_IP == protocol) { 279 protocol = answer->protocol; 280 break; 281 } 282 if (IPPROTO_IP == answer->protocol) 283 break; 284 } 285 err = -EPROTONOSUPPORT; 286 } 287 288 if (unlikely(err)) { 289 if (try_loading_module < 2) { 290 rcu_read_unlock(); 291 /* 292 * Be more specific, e.g. net-pf-2-proto-132-type-1 293 * (net-pf-PF_INET-proto-IPPROTO_SCTP-type-SOCK_STREAM) 294 */ 295 if (++try_loading_module == 1) 296 request_module("net-pf-%d-proto-%d-type-%d", 297 PF_INET, protocol, sock->type); 298 /* 299 * Fall back to generic, e.g. net-pf-2-proto-132 300 * (net-pf-PF_INET-proto-IPPROTO_SCTP) 301 */ 302 else 303 request_module("net-pf-%d-proto-%d", 304 PF_INET, protocol); 305 goto lookup_protocol; 306 } else 307 goto out_rcu_unlock; 308 } 309 310 err = -EPERM; 311 if (sock->type == SOCK_RAW && !kern && 312 !ns_capable(net->user_ns, CAP_NET_RAW)) 313 goto out_rcu_unlock; 314 315 sock->ops = answer->ops; 316 answer_prot = answer->prot; 317 answer_flags = answer->flags; 318 rcu_read_unlock(); 319 320 WARN_ON(!answer_prot->slab); 321 322 err = -ENOBUFS; 323 sk = sk_alloc(net, PF_INET, GFP_KERNEL, answer_prot, kern); 324 if (!sk) 325 goto out; 326 327 err = 0; 328 if (INET_PROTOSW_REUSE & answer_flags) 329 sk->sk_reuse = SK_CAN_REUSE; 330 331 inet = inet_sk(sk); 332 inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0; 333 334 inet->nodefrag = 0; 335 336 if (SOCK_RAW == sock->type) { 337 inet->inet_num = protocol; 338 if (IPPROTO_RAW == protocol) 339 inet->hdrincl = 1; 340 } 341 342 if (net->ipv4.sysctl_ip_no_pmtu_disc) 343 inet->pmtudisc = IP_PMTUDISC_DONT; 344 else 345 inet->pmtudisc = IP_PMTUDISC_WANT; 346 347 inet->inet_id = 0; 348 349 sock_init_data(sock, sk); 350 351 sk->sk_destruct = inet_sock_destruct; 352 sk->sk_protocol = protocol; 353 sk->sk_backlog_rcv = sk->sk_prot->backlog_rcv; 354 355 inet->uc_ttl = -1; 356 inet->mc_loop = 1; 357 inet->mc_ttl = 1; 358 inet->mc_all = 1; 359 inet->mc_index = 0; 360 inet->mc_list = NULL; 361 inet->rcv_tos = 0; 362 363 sk_refcnt_debug_inc(sk); 364 365 if (inet->inet_num) { 366 /* It assumes that any protocol which allows 367 * the user to assign a number at socket 368 * creation time automatically 369 * shares. 370 */ 371 inet->inet_sport = htons(inet->inet_num); 372 /* Add to protocol hash chains. */ 373 err = sk->sk_prot->hash(sk); 374 if (err) { 375 sk_common_release(sk); 376 goto out; 377 } 378 } 379 380 if (sk->sk_prot->init) { 381 err = sk->sk_prot->init(sk); 382 if (err) 383 sk_common_release(sk); 384 } 385 out: 386 return err; 387 out_rcu_unlock: 388 rcu_read_unlock(); 389 goto out; 390 } 391 392 393 /* 394 * The peer socket should always be NULL (or else). When we call this 395 * function we are destroying the object and from then on nobody 396 * should refer to it. 397 */ 398 int inet_release(struct socket *sock) 399 { 400 struct sock *sk = sock->sk; 401 402 if (sk) { 403 long timeout; 404 405 /* Applications forget to leave groups before exiting */ 406 ip_mc_drop_socket(sk); 407 408 /* If linger is set, we don't return until the close 409 * is complete. Otherwise we return immediately. The 410 * actually closing is done the same either way. 411 * 412 * If the close is due to the process exiting, we never 413 * linger.. 414 */ 415 timeout = 0; 416 if (sock_flag(sk, SOCK_LINGER) && 417 !(current->flags & PF_EXITING)) 418 timeout = sk->sk_lingertime; 419 sock->sk = NULL; 420 sk->sk_prot->close(sk, timeout); 421 } 422 return 0; 423 } 424 EXPORT_SYMBOL(inet_release); 425 426 int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) 427 { 428 struct sockaddr_in *addr = (struct sockaddr_in *)uaddr; 429 struct sock *sk = sock->sk; 430 struct inet_sock *inet = inet_sk(sk); 431 struct net *net = sock_net(sk); 432 unsigned short snum; 433 int chk_addr_ret; 434 u32 tb_id = RT_TABLE_LOCAL; 435 int err; 436 437 /* If the socket has its own bind function then use it. (RAW) */ 438 if (sk->sk_prot->bind) { 439 err = sk->sk_prot->bind(sk, uaddr, addr_len); 440 goto out; 441 } 442 err = -EINVAL; 443 if (addr_len < sizeof(struct sockaddr_in)) 444 goto out; 445 446 if (addr->sin_family != AF_INET) { 447 /* Compatibility games : accept AF_UNSPEC (mapped to AF_INET) 448 * only if s_addr is INADDR_ANY. 449 */ 450 err = -EAFNOSUPPORT; 451 if (addr->sin_family != AF_UNSPEC || 452 addr->sin_addr.s_addr != htonl(INADDR_ANY)) 453 goto out; 454 } 455 456 tb_id = l3mdev_fib_table_by_index(net, sk->sk_bound_dev_if) ? : tb_id; 457 chk_addr_ret = inet_addr_type_table(net, addr->sin_addr.s_addr, tb_id); 458 459 /* Not specified by any standard per-se, however it breaks too 460 * many applications when removed. It is unfortunate since 461 * allowing applications to make a non-local bind solves 462 * several problems with systems using dynamic addressing. 463 * (ie. your servers still start up even if your ISDN link 464 * is temporarily down) 465 */ 466 err = -EADDRNOTAVAIL; 467 if (!net->ipv4.sysctl_ip_nonlocal_bind && 468 !(inet->freebind || inet->transparent) && 469 addr->sin_addr.s_addr != htonl(INADDR_ANY) && 470 chk_addr_ret != RTN_LOCAL && 471 chk_addr_ret != RTN_MULTICAST && 472 chk_addr_ret != RTN_BROADCAST) 473 goto out; 474 475 snum = ntohs(addr->sin_port); 476 err = -EACCES; 477 if (snum && snum < PROT_SOCK && 478 !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE)) 479 goto out; 480 481 /* We keep a pair of addresses. rcv_saddr is the one 482 * used by hash lookups, and saddr is used for transmit. 483 * 484 * In the BSD API these are the same except where it 485 * would be illegal to use them (multicast/broadcast) in 486 * which case the sending device address is used. 487 */ 488 lock_sock(sk); 489 490 /* Check these errors (active socket, double bind). */ 491 err = -EINVAL; 492 if (sk->sk_state != TCP_CLOSE || inet->inet_num) 493 goto out_release_sock; 494 495 inet->inet_rcv_saddr = inet->inet_saddr = addr->sin_addr.s_addr; 496 if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST) 497 inet->inet_saddr = 0; /* Use device */ 498 499 /* Make sure we are allowed to bind here. */ 500 if ((snum || !inet->bind_address_no_port) && 501 sk->sk_prot->get_port(sk, snum)) { 502 inet->inet_saddr = inet->inet_rcv_saddr = 0; 503 err = -EADDRINUSE; 504 goto out_release_sock; 505 } 506 507 if (inet->inet_rcv_saddr) 508 sk->sk_userlocks |= SOCK_BINDADDR_LOCK; 509 if (snum) 510 sk->sk_userlocks |= SOCK_BINDPORT_LOCK; 511 inet->inet_sport = htons(inet->inet_num); 512 inet->inet_daddr = 0; 513 inet->inet_dport = 0; 514 sk_dst_reset(sk); 515 err = 0; 516 out_release_sock: 517 release_sock(sk); 518 out: 519 return err; 520 } 521 EXPORT_SYMBOL(inet_bind); 522 523 int inet_dgram_connect(struct socket *sock, struct sockaddr *uaddr, 524 int addr_len, int flags) 525 { 526 struct sock *sk = sock->sk; 527 528 if (addr_len < sizeof(uaddr->sa_family)) 529 return -EINVAL; 530 if (uaddr->sa_family == AF_UNSPEC) 531 return sk->sk_prot->disconnect(sk, flags); 532 533 if (!inet_sk(sk)->inet_num && inet_autobind(sk)) 534 return -EAGAIN; 535 return sk->sk_prot->connect(sk, uaddr, addr_len); 536 } 537 EXPORT_SYMBOL(inet_dgram_connect); 538 539 static long inet_wait_for_connect(struct sock *sk, long timeo, int writebias) 540 { 541 DEFINE_WAIT(wait); 542 543 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 544 sk->sk_write_pending += writebias; 545 546 /* Basic assumption: if someone sets sk->sk_err, he _must_ 547 * change state of the socket from TCP_SYN_*. 548 * Connect() does not allow to get error notifications 549 * without closing the socket. 550 */ 551 while ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) { 552 release_sock(sk); 553 timeo = schedule_timeout(timeo); 554 lock_sock(sk); 555 if (signal_pending(current) || !timeo) 556 break; 557 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 558 } 559 finish_wait(sk_sleep(sk), &wait); 560 sk->sk_write_pending -= writebias; 561 return timeo; 562 } 563 564 /* 565 * Connect to a remote host. There is regrettably still a little 566 * TCP 'magic' in here. 567 */ 568 int __inet_stream_connect(struct socket *sock, struct sockaddr *uaddr, 569 int addr_len, int flags) 570 { 571 struct sock *sk = sock->sk; 572 int err; 573 long timeo; 574 575 if (addr_len < sizeof(uaddr->sa_family)) 576 return -EINVAL; 577 578 if (uaddr->sa_family == AF_UNSPEC) { 579 err = sk->sk_prot->disconnect(sk, flags); 580 sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED; 581 goto out; 582 } 583 584 switch (sock->state) { 585 default: 586 err = -EINVAL; 587 goto out; 588 case SS_CONNECTED: 589 err = -EISCONN; 590 goto out; 591 case SS_CONNECTING: 592 err = -EALREADY; 593 /* Fall out of switch with err, set for this state */ 594 break; 595 case SS_UNCONNECTED: 596 err = -EISCONN; 597 if (sk->sk_state != TCP_CLOSE) 598 goto out; 599 600 err = sk->sk_prot->connect(sk, uaddr, addr_len); 601 if (err < 0) 602 goto out; 603 604 sock->state = SS_CONNECTING; 605 606 /* Just entered SS_CONNECTING state; the only 607 * difference is that return value in non-blocking 608 * case is EINPROGRESS, rather than EALREADY. 609 */ 610 err = -EINPROGRESS; 611 break; 612 } 613 614 timeo = sock_sndtimeo(sk, flags & O_NONBLOCK); 615 616 if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) { 617 int writebias = (sk->sk_protocol == IPPROTO_TCP) && 618 tcp_sk(sk)->fastopen_req && 619 tcp_sk(sk)->fastopen_req->data ? 1 : 0; 620 621 /* Error code is set above */ 622 if (!timeo || !inet_wait_for_connect(sk, timeo, writebias)) 623 goto out; 624 625 err = sock_intr_errno(timeo); 626 if (signal_pending(current)) 627 goto out; 628 } 629 630 /* Connection was closed by RST, timeout, ICMP error 631 * or another process disconnected us. 632 */ 633 if (sk->sk_state == TCP_CLOSE) 634 goto sock_error; 635 636 /* sk->sk_err may be not zero now, if RECVERR was ordered by user 637 * and error was received after socket entered established state. 638 * Hence, it is handled normally after connect() return successfully. 639 */ 640 641 sock->state = SS_CONNECTED; 642 err = 0; 643 out: 644 return err; 645 646 sock_error: 647 err = sock_error(sk) ? : -ECONNABORTED; 648 sock->state = SS_UNCONNECTED; 649 if (sk->sk_prot->disconnect(sk, flags)) 650 sock->state = SS_DISCONNECTING; 651 goto out; 652 } 653 EXPORT_SYMBOL(__inet_stream_connect); 654 655 int inet_stream_connect(struct socket *sock, struct sockaddr *uaddr, 656 int addr_len, int flags) 657 { 658 int err; 659 660 lock_sock(sock->sk); 661 err = __inet_stream_connect(sock, uaddr, addr_len, flags); 662 release_sock(sock->sk); 663 return err; 664 } 665 EXPORT_SYMBOL(inet_stream_connect); 666 667 /* 668 * Accept a pending connection. The TCP layer now gives BSD semantics. 669 */ 670 671 int inet_accept(struct socket *sock, struct socket *newsock, int flags) 672 { 673 struct sock *sk1 = sock->sk; 674 int err = -EINVAL; 675 struct sock *sk2 = sk1->sk_prot->accept(sk1, flags, &err); 676 677 if (!sk2) 678 goto do_err; 679 680 lock_sock(sk2); 681 682 sock_rps_record_flow(sk2); 683 WARN_ON(!((1 << sk2->sk_state) & 684 (TCPF_ESTABLISHED | TCPF_SYN_RECV | 685 TCPF_CLOSE_WAIT | TCPF_CLOSE))); 686 687 sock_graft(sk2, newsock); 688 689 newsock->state = SS_CONNECTED; 690 err = 0; 691 release_sock(sk2); 692 do_err: 693 return err; 694 } 695 EXPORT_SYMBOL(inet_accept); 696 697 698 /* 699 * This does both peername and sockname. 700 */ 701 int inet_getname(struct socket *sock, struct sockaddr *uaddr, 702 int *uaddr_len, int peer) 703 { 704 struct sock *sk = sock->sk; 705 struct inet_sock *inet = inet_sk(sk); 706 DECLARE_SOCKADDR(struct sockaddr_in *, sin, uaddr); 707 708 sin->sin_family = AF_INET; 709 if (peer) { 710 if (!inet->inet_dport || 711 (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) && 712 peer == 1)) 713 return -ENOTCONN; 714 sin->sin_port = inet->inet_dport; 715 sin->sin_addr.s_addr = inet->inet_daddr; 716 } else { 717 __be32 addr = inet->inet_rcv_saddr; 718 if (!addr) 719 addr = inet->inet_saddr; 720 sin->sin_port = inet->inet_sport; 721 sin->sin_addr.s_addr = addr; 722 } 723 memset(sin->sin_zero, 0, sizeof(sin->sin_zero)); 724 *uaddr_len = sizeof(*sin); 725 return 0; 726 } 727 EXPORT_SYMBOL(inet_getname); 728 729 int inet_sendmsg(struct socket *sock, struct msghdr *msg, size_t size) 730 { 731 struct sock *sk = sock->sk; 732 733 sock_rps_record_flow(sk); 734 735 /* We may need to bind the socket. */ 736 if (!inet_sk(sk)->inet_num && !sk->sk_prot->no_autobind && 737 inet_autobind(sk)) 738 return -EAGAIN; 739 740 return sk->sk_prot->sendmsg(sk, msg, size); 741 } 742 EXPORT_SYMBOL(inet_sendmsg); 743 744 ssize_t inet_sendpage(struct socket *sock, struct page *page, int offset, 745 size_t size, int flags) 746 { 747 struct sock *sk = sock->sk; 748 749 sock_rps_record_flow(sk); 750 751 /* We may need to bind the socket. */ 752 if (!inet_sk(sk)->inet_num && !sk->sk_prot->no_autobind && 753 inet_autobind(sk)) 754 return -EAGAIN; 755 756 if (sk->sk_prot->sendpage) 757 return sk->sk_prot->sendpage(sk, page, offset, size, flags); 758 return sock_no_sendpage(sock, page, offset, size, flags); 759 } 760 EXPORT_SYMBOL(inet_sendpage); 761 762 int inet_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 763 int flags) 764 { 765 struct sock *sk = sock->sk; 766 int addr_len = 0; 767 int err; 768 769 sock_rps_record_flow(sk); 770 771 err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT, 772 flags & ~MSG_DONTWAIT, &addr_len); 773 if (err >= 0) 774 msg->msg_namelen = addr_len; 775 return err; 776 } 777 EXPORT_SYMBOL(inet_recvmsg); 778 779 int inet_shutdown(struct socket *sock, int how) 780 { 781 struct sock *sk = sock->sk; 782 int err = 0; 783 784 /* This should really check to make sure 785 * the socket is a TCP socket. (WHY AC...) 786 */ 787 how++; /* maps 0->1 has the advantage of making bit 1 rcvs and 788 1->2 bit 2 snds. 789 2->3 */ 790 if ((how & ~SHUTDOWN_MASK) || !how) /* MAXINT->0 */ 791 return -EINVAL; 792 793 lock_sock(sk); 794 if (sock->state == SS_CONNECTING) { 795 if ((1 << sk->sk_state) & 796 (TCPF_SYN_SENT | TCPF_SYN_RECV | TCPF_CLOSE)) 797 sock->state = SS_DISCONNECTING; 798 else 799 sock->state = SS_CONNECTED; 800 } 801 802 switch (sk->sk_state) { 803 case TCP_CLOSE: 804 err = -ENOTCONN; 805 /* Hack to wake up other listeners, who can poll for 806 POLLHUP, even on eg. unconnected UDP sockets -- RR */ 807 default: 808 sk->sk_shutdown |= how; 809 if (sk->sk_prot->shutdown) 810 sk->sk_prot->shutdown(sk, how); 811 break; 812 813 /* Remaining two branches are temporary solution for missing 814 * close() in multithreaded environment. It is _not_ a good idea, 815 * but we have no choice until close() is repaired at VFS level. 816 */ 817 case TCP_LISTEN: 818 if (!(how & RCV_SHUTDOWN)) 819 break; 820 /* Fall through */ 821 case TCP_SYN_SENT: 822 err = sk->sk_prot->disconnect(sk, O_NONBLOCK); 823 sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED; 824 break; 825 } 826 827 /* Wake up anyone sleeping in poll. */ 828 sk->sk_state_change(sk); 829 release_sock(sk); 830 return err; 831 } 832 EXPORT_SYMBOL(inet_shutdown); 833 834 /* 835 * ioctl() calls you can issue on an INET socket. Most of these are 836 * device configuration and stuff and very rarely used. Some ioctls 837 * pass on to the socket itself. 838 * 839 * NOTE: I like the idea of a module for the config stuff. ie ifconfig 840 * loads the devconfigure module does its configuring and unloads it. 841 * There's a good 20K of config code hanging around the kernel. 842 */ 843 844 int inet_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) 845 { 846 struct sock *sk = sock->sk; 847 int err = 0; 848 struct net *net = sock_net(sk); 849 850 switch (cmd) { 851 case SIOCGSTAMP: 852 err = sock_get_timestamp(sk, (struct timeval __user *)arg); 853 break; 854 case SIOCGSTAMPNS: 855 err = sock_get_timestampns(sk, (struct timespec __user *)arg); 856 break; 857 case SIOCADDRT: 858 case SIOCDELRT: 859 case SIOCRTMSG: 860 err = ip_rt_ioctl(net, cmd, (void __user *)arg); 861 break; 862 case SIOCDARP: 863 case SIOCGARP: 864 case SIOCSARP: 865 err = arp_ioctl(net, cmd, (void __user *)arg); 866 break; 867 case SIOCGIFADDR: 868 case SIOCSIFADDR: 869 case SIOCGIFBRDADDR: 870 case SIOCSIFBRDADDR: 871 case SIOCGIFNETMASK: 872 case SIOCSIFNETMASK: 873 case SIOCGIFDSTADDR: 874 case SIOCSIFDSTADDR: 875 case SIOCSIFPFLAGS: 876 case SIOCGIFPFLAGS: 877 case SIOCSIFFLAGS: 878 err = devinet_ioctl(net, cmd, (void __user *)arg); 879 break; 880 default: 881 if (sk->sk_prot->ioctl) 882 err = sk->sk_prot->ioctl(sk, cmd, arg); 883 else 884 err = -ENOIOCTLCMD; 885 break; 886 } 887 return err; 888 } 889 EXPORT_SYMBOL(inet_ioctl); 890 891 #ifdef CONFIG_COMPAT 892 static int inet_compat_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) 893 { 894 struct sock *sk = sock->sk; 895 int err = -ENOIOCTLCMD; 896 897 if (sk->sk_prot->compat_ioctl) 898 err = sk->sk_prot->compat_ioctl(sk, cmd, arg); 899 900 return err; 901 } 902 #endif 903 904 const struct proto_ops inet_stream_ops = { 905 .family = PF_INET, 906 .owner = THIS_MODULE, 907 .release = inet_release, 908 .bind = inet_bind, 909 .connect = inet_stream_connect, 910 .socketpair = sock_no_socketpair, 911 .accept = inet_accept, 912 .getname = inet_getname, 913 .poll = tcp_poll, 914 .ioctl = inet_ioctl, 915 .listen = inet_listen, 916 .shutdown = inet_shutdown, 917 .setsockopt = sock_common_setsockopt, 918 .getsockopt = sock_common_getsockopt, 919 .sendmsg = inet_sendmsg, 920 .recvmsg = inet_recvmsg, 921 .mmap = sock_no_mmap, 922 .sendpage = inet_sendpage, 923 .splice_read = tcp_splice_read, 924 #ifdef CONFIG_COMPAT 925 .compat_setsockopt = compat_sock_common_setsockopt, 926 .compat_getsockopt = compat_sock_common_getsockopt, 927 .compat_ioctl = inet_compat_ioctl, 928 #endif 929 }; 930 EXPORT_SYMBOL(inet_stream_ops); 931 932 const struct proto_ops inet_dgram_ops = { 933 .family = PF_INET, 934 .owner = THIS_MODULE, 935 .release = inet_release, 936 .bind = inet_bind, 937 .connect = inet_dgram_connect, 938 .socketpair = sock_no_socketpair, 939 .accept = sock_no_accept, 940 .getname = inet_getname, 941 .poll = udp_poll, 942 .ioctl = inet_ioctl, 943 .listen = sock_no_listen, 944 .shutdown = inet_shutdown, 945 .setsockopt = sock_common_setsockopt, 946 .getsockopt = sock_common_getsockopt, 947 .sendmsg = inet_sendmsg, 948 .recvmsg = inet_recvmsg, 949 .mmap = sock_no_mmap, 950 .sendpage = inet_sendpage, 951 #ifdef CONFIG_COMPAT 952 .compat_setsockopt = compat_sock_common_setsockopt, 953 .compat_getsockopt = compat_sock_common_getsockopt, 954 .compat_ioctl = inet_compat_ioctl, 955 #endif 956 }; 957 EXPORT_SYMBOL(inet_dgram_ops); 958 959 /* 960 * For SOCK_RAW sockets; should be the same as inet_dgram_ops but without 961 * udp_poll 962 */ 963 static const struct proto_ops inet_sockraw_ops = { 964 .family = PF_INET, 965 .owner = THIS_MODULE, 966 .release = inet_release, 967 .bind = inet_bind, 968 .connect = inet_dgram_connect, 969 .socketpair = sock_no_socketpair, 970 .accept = sock_no_accept, 971 .getname = inet_getname, 972 .poll = datagram_poll, 973 .ioctl = inet_ioctl, 974 .listen = sock_no_listen, 975 .shutdown = inet_shutdown, 976 .setsockopt = sock_common_setsockopt, 977 .getsockopt = sock_common_getsockopt, 978 .sendmsg = inet_sendmsg, 979 .recvmsg = inet_recvmsg, 980 .mmap = sock_no_mmap, 981 .sendpage = inet_sendpage, 982 #ifdef CONFIG_COMPAT 983 .compat_setsockopt = compat_sock_common_setsockopt, 984 .compat_getsockopt = compat_sock_common_getsockopt, 985 .compat_ioctl = inet_compat_ioctl, 986 #endif 987 }; 988 989 static const struct net_proto_family inet_family_ops = { 990 .family = PF_INET, 991 .create = inet_create, 992 .owner = THIS_MODULE, 993 }; 994 995 /* Upon startup we insert all the elements in inetsw_array[] into 996 * the linked list inetsw. 997 */ 998 static struct inet_protosw inetsw_array[] = 999 { 1000 { 1001 .type = SOCK_STREAM, 1002 .protocol = IPPROTO_TCP, 1003 .prot = &tcp_prot, 1004 .ops = &inet_stream_ops, 1005 .flags = INET_PROTOSW_PERMANENT | 1006 INET_PROTOSW_ICSK, 1007 }, 1008 1009 { 1010 .type = SOCK_DGRAM, 1011 .protocol = IPPROTO_UDP, 1012 .prot = &udp_prot, 1013 .ops = &inet_dgram_ops, 1014 .flags = INET_PROTOSW_PERMANENT, 1015 }, 1016 1017 { 1018 .type = SOCK_DGRAM, 1019 .protocol = IPPROTO_ICMP, 1020 .prot = &ping_prot, 1021 .ops = &inet_dgram_ops, 1022 .flags = INET_PROTOSW_REUSE, 1023 }, 1024 1025 { 1026 .type = SOCK_RAW, 1027 .protocol = IPPROTO_IP, /* wild card */ 1028 .prot = &raw_prot, 1029 .ops = &inet_sockraw_ops, 1030 .flags = INET_PROTOSW_REUSE, 1031 } 1032 }; 1033 1034 #define INETSW_ARRAY_LEN ARRAY_SIZE(inetsw_array) 1035 1036 void inet_register_protosw(struct inet_protosw *p) 1037 { 1038 struct list_head *lh; 1039 struct inet_protosw *answer; 1040 int protocol = p->protocol; 1041 struct list_head *last_perm; 1042 1043 spin_lock_bh(&inetsw_lock); 1044 1045 if (p->type >= SOCK_MAX) 1046 goto out_illegal; 1047 1048 /* If we are trying to override a permanent protocol, bail. */ 1049 last_perm = &inetsw[p->type]; 1050 list_for_each(lh, &inetsw[p->type]) { 1051 answer = list_entry(lh, struct inet_protosw, list); 1052 /* Check only the non-wild match. */ 1053 if ((INET_PROTOSW_PERMANENT & answer->flags) == 0) 1054 break; 1055 if (protocol == answer->protocol) 1056 goto out_permanent; 1057 last_perm = lh; 1058 } 1059 1060 /* Add the new entry after the last permanent entry if any, so that 1061 * the new entry does not override a permanent entry when matched with 1062 * a wild-card protocol. But it is allowed to override any existing 1063 * non-permanent entry. This means that when we remove this entry, the 1064 * system automatically returns to the old behavior. 1065 */ 1066 list_add_rcu(&p->list, last_perm); 1067 out: 1068 spin_unlock_bh(&inetsw_lock); 1069 1070 return; 1071 1072 out_permanent: 1073 pr_err("Attempt to override permanent protocol %d\n", protocol); 1074 goto out; 1075 1076 out_illegal: 1077 pr_err("Ignoring attempt to register invalid socket type %d\n", 1078 p->type); 1079 goto out; 1080 } 1081 EXPORT_SYMBOL(inet_register_protosw); 1082 1083 void inet_unregister_protosw(struct inet_protosw *p) 1084 { 1085 if (INET_PROTOSW_PERMANENT & p->flags) { 1086 pr_err("Attempt to unregister permanent protocol %d\n", 1087 p->protocol); 1088 } else { 1089 spin_lock_bh(&inetsw_lock); 1090 list_del_rcu(&p->list); 1091 spin_unlock_bh(&inetsw_lock); 1092 1093 synchronize_net(); 1094 } 1095 } 1096 EXPORT_SYMBOL(inet_unregister_protosw); 1097 1098 static int inet_sk_reselect_saddr(struct sock *sk) 1099 { 1100 struct inet_sock *inet = inet_sk(sk); 1101 __be32 old_saddr = inet->inet_saddr; 1102 __be32 daddr = inet->inet_daddr; 1103 struct flowi4 *fl4; 1104 struct rtable *rt; 1105 __be32 new_saddr; 1106 struct ip_options_rcu *inet_opt; 1107 1108 inet_opt = rcu_dereference_protected(inet->inet_opt, 1109 sock_owned_by_user(sk)); 1110 if (inet_opt && inet_opt->opt.srr) 1111 daddr = inet_opt->opt.faddr; 1112 1113 /* Query new route. */ 1114 fl4 = &inet->cork.fl.u.ip4; 1115 rt = ip_route_connect(fl4, daddr, 0, RT_CONN_FLAGS(sk), 1116 sk->sk_bound_dev_if, sk->sk_protocol, 1117 inet->inet_sport, inet->inet_dport, sk); 1118 if (IS_ERR(rt)) 1119 return PTR_ERR(rt); 1120 1121 sk_setup_caps(sk, &rt->dst); 1122 1123 new_saddr = fl4->saddr; 1124 1125 if (new_saddr == old_saddr) 1126 return 0; 1127 1128 if (sock_net(sk)->ipv4.sysctl_ip_dynaddr > 1) { 1129 pr_info("%s(): shifting inet->saddr from %pI4 to %pI4\n", 1130 __func__, &old_saddr, &new_saddr); 1131 } 1132 1133 inet->inet_saddr = inet->inet_rcv_saddr = new_saddr; 1134 1135 /* 1136 * XXX The only one ugly spot where we need to 1137 * XXX really change the sockets identity after 1138 * XXX it has entered the hashes. -DaveM 1139 * 1140 * Besides that, it does not check for connection 1141 * uniqueness. Wait for troubles. 1142 */ 1143 return __sk_prot_rehash(sk); 1144 } 1145 1146 int inet_sk_rebuild_header(struct sock *sk) 1147 { 1148 struct inet_sock *inet = inet_sk(sk); 1149 struct rtable *rt = (struct rtable *)__sk_dst_check(sk, 0); 1150 __be32 daddr; 1151 struct ip_options_rcu *inet_opt; 1152 struct flowi4 *fl4; 1153 int err; 1154 1155 /* Route is OK, nothing to do. */ 1156 if (rt) 1157 return 0; 1158 1159 /* Reroute. */ 1160 rcu_read_lock(); 1161 inet_opt = rcu_dereference(inet->inet_opt); 1162 daddr = inet->inet_daddr; 1163 if (inet_opt && inet_opt->opt.srr) 1164 daddr = inet_opt->opt.faddr; 1165 rcu_read_unlock(); 1166 fl4 = &inet->cork.fl.u.ip4; 1167 rt = ip_route_output_ports(sock_net(sk), fl4, sk, daddr, inet->inet_saddr, 1168 inet->inet_dport, inet->inet_sport, 1169 sk->sk_protocol, RT_CONN_FLAGS(sk), 1170 sk->sk_bound_dev_if); 1171 if (!IS_ERR(rt)) { 1172 err = 0; 1173 sk_setup_caps(sk, &rt->dst); 1174 } else { 1175 err = PTR_ERR(rt); 1176 1177 /* Routing failed... */ 1178 sk->sk_route_caps = 0; 1179 /* 1180 * Other protocols have to map its equivalent state to TCP_SYN_SENT. 1181 * DCCP maps its DCCP_REQUESTING state to TCP_SYN_SENT. -acme 1182 */ 1183 if (!sock_net(sk)->ipv4.sysctl_ip_dynaddr || 1184 sk->sk_state != TCP_SYN_SENT || 1185 (sk->sk_userlocks & SOCK_BINDADDR_LOCK) || 1186 (err = inet_sk_reselect_saddr(sk)) != 0) 1187 sk->sk_err_soft = -err; 1188 } 1189 1190 return err; 1191 } 1192 EXPORT_SYMBOL(inet_sk_rebuild_header); 1193 1194 static struct sk_buff *inet_gso_segment(struct sk_buff *skb, 1195 netdev_features_t features) 1196 { 1197 struct sk_buff *segs = ERR_PTR(-EINVAL); 1198 const struct net_offload *ops; 1199 unsigned int offset = 0; 1200 bool udpfrag, encap; 1201 struct iphdr *iph; 1202 int proto; 1203 int nhoff; 1204 int ihl; 1205 int id; 1206 1207 if (unlikely(skb_shinfo(skb)->gso_type & 1208 ~(SKB_GSO_TCPV4 | 1209 SKB_GSO_UDP | 1210 SKB_GSO_DODGY | 1211 SKB_GSO_TCP_ECN | 1212 SKB_GSO_GRE | 1213 SKB_GSO_GRE_CSUM | 1214 SKB_GSO_IPIP | 1215 SKB_GSO_SIT | 1216 SKB_GSO_TCPV6 | 1217 SKB_GSO_UDP_TUNNEL | 1218 SKB_GSO_UDP_TUNNEL_CSUM | 1219 SKB_GSO_TUNNEL_REMCSUM | 1220 0))) 1221 goto out; 1222 1223 skb_reset_network_header(skb); 1224 nhoff = skb_network_header(skb) - skb_mac_header(skb); 1225 if (unlikely(!pskb_may_pull(skb, sizeof(*iph)))) 1226 goto out; 1227 1228 iph = ip_hdr(skb); 1229 ihl = iph->ihl * 4; 1230 if (ihl < sizeof(*iph)) 1231 goto out; 1232 1233 id = ntohs(iph->id); 1234 proto = iph->protocol; 1235 1236 /* Warning: after this point, iph might be no longer valid */ 1237 if (unlikely(!pskb_may_pull(skb, ihl))) 1238 goto out; 1239 __skb_pull(skb, ihl); 1240 1241 encap = SKB_GSO_CB(skb)->encap_level > 0; 1242 if (encap) 1243 features &= skb->dev->hw_enc_features; 1244 SKB_GSO_CB(skb)->encap_level += ihl; 1245 1246 skb_reset_transport_header(skb); 1247 1248 segs = ERR_PTR(-EPROTONOSUPPORT); 1249 1250 if (skb->encapsulation && 1251 skb_shinfo(skb)->gso_type & (SKB_GSO_SIT|SKB_GSO_IPIP)) 1252 udpfrag = proto == IPPROTO_UDP && encap; 1253 else 1254 udpfrag = proto == IPPROTO_UDP && !skb->encapsulation; 1255 1256 ops = rcu_dereference(inet_offloads[proto]); 1257 if (likely(ops && ops->callbacks.gso_segment)) 1258 segs = ops->callbacks.gso_segment(skb, features); 1259 1260 if (IS_ERR_OR_NULL(segs)) 1261 goto out; 1262 1263 skb = segs; 1264 do { 1265 iph = (struct iphdr *)(skb_mac_header(skb) + nhoff); 1266 if (udpfrag) { 1267 iph->id = htons(id); 1268 iph->frag_off = htons(offset >> 3); 1269 if (skb->next) 1270 iph->frag_off |= htons(IP_MF); 1271 offset += skb->len - nhoff - ihl; 1272 } else { 1273 iph->id = htons(id++); 1274 } 1275 iph->tot_len = htons(skb->len - nhoff); 1276 ip_send_check(iph); 1277 if (encap) 1278 skb_reset_inner_headers(skb); 1279 skb->network_header = (u8 *)iph - skb->head; 1280 } while ((skb = skb->next)); 1281 1282 out: 1283 return segs; 1284 } 1285 1286 static struct sk_buff **inet_gro_receive(struct sk_buff **head, 1287 struct sk_buff *skb) 1288 { 1289 const struct net_offload *ops; 1290 struct sk_buff **pp = NULL; 1291 struct sk_buff *p; 1292 const struct iphdr *iph; 1293 unsigned int hlen; 1294 unsigned int off; 1295 unsigned int id; 1296 int flush = 1; 1297 int proto; 1298 1299 off = skb_gro_offset(skb); 1300 hlen = off + sizeof(*iph); 1301 iph = skb_gro_header_fast(skb, off); 1302 if (skb_gro_header_hard(skb, hlen)) { 1303 iph = skb_gro_header_slow(skb, hlen, off); 1304 if (unlikely(!iph)) 1305 goto out; 1306 } 1307 1308 proto = iph->protocol; 1309 1310 rcu_read_lock(); 1311 ops = rcu_dereference(inet_offloads[proto]); 1312 if (!ops || !ops->callbacks.gro_receive) 1313 goto out_unlock; 1314 1315 if (*(u8 *)iph != 0x45) 1316 goto out_unlock; 1317 1318 if (unlikely(ip_fast_csum((u8 *)iph, 5))) 1319 goto out_unlock; 1320 1321 id = ntohl(*(__be32 *)&iph->id); 1322 flush = (u16)((ntohl(*(__be32 *)iph) ^ skb_gro_len(skb)) | (id & ~IP_DF)); 1323 id >>= 16; 1324 1325 for (p = *head; p; p = p->next) { 1326 struct iphdr *iph2; 1327 1328 if (!NAPI_GRO_CB(p)->same_flow) 1329 continue; 1330 1331 iph2 = (struct iphdr *)(p->data + off); 1332 /* The above works because, with the exception of the top 1333 * (inner most) layer, we only aggregate pkts with the same 1334 * hdr length so all the hdrs we'll need to verify will start 1335 * at the same offset. 1336 */ 1337 if ((iph->protocol ^ iph2->protocol) | 1338 ((__force u32)iph->saddr ^ (__force u32)iph2->saddr) | 1339 ((__force u32)iph->daddr ^ (__force u32)iph2->daddr)) { 1340 NAPI_GRO_CB(p)->same_flow = 0; 1341 continue; 1342 } 1343 1344 /* All fields must match except length and checksum. */ 1345 NAPI_GRO_CB(p)->flush |= 1346 (iph->ttl ^ iph2->ttl) | 1347 (iph->tos ^ iph2->tos) | 1348 ((iph->frag_off ^ iph2->frag_off) & htons(IP_DF)); 1349 1350 /* Save the IP ID check to be included later when we get to 1351 * the transport layer so only the inner most IP ID is checked. 1352 * This is because some GSO/TSO implementations do not 1353 * correctly increment the IP ID for the outer hdrs. 1354 */ 1355 NAPI_GRO_CB(p)->flush_id = 1356 ((u16)(ntohs(iph2->id) + NAPI_GRO_CB(p)->count) ^ id); 1357 NAPI_GRO_CB(p)->flush |= flush; 1358 } 1359 1360 NAPI_GRO_CB(skb)->flush |= flush; 1361 skb_set_network_header(skb, off); 1362 /* The above will be needed by the transport layer if there is one 1363 * immediately following this IP hdr. 1364 */ 1365 1366 /* Note : No need to call skb_gro_postpull_rcsum() here, 1367 * as we already checked checksum over ipv4 header was 0 1368 */ 1369 skb_gro_pull(skb, sizeof(*iph)); 1370 skb_set_transport_header(skb, skb_gro_offset(skb)); 1371 1372 pp = ops->callbacks.gro_receive(head, skb); 1373 1374 out_unlock: 1375 rcu_read_unlock(); 1376 1377 out: 1378 NAPI_GRO_CB(skb)->flush |= flush; 1379 1380 return pp; 1381 } 1382 1383 static struct sk_buff **ipip_gro_receive(struct sk_buff **head, 1384 struct sk_buff *skb) 1385 { 1386 if (NAPI_GRO_CB(skb)->encap_mark) { 1387 NAPI_GRO_CB(skb)->flush = 1; 1388 return NULL; 1389 } 1390 1391 NAPI_GRO_CB(skb)->encap_mark = 1; 1392 1393 return inet_gro_receive(head, skb); 1394 } 1395 1396 #define SECONDS_PER_DAY 86400 1397 1398 /* inet_current_timestamp - Return IP network timestamp 1399 * 1400 * Return milliseconds since midnight in network byte order. 1401 */ 1402 __be32 inet_current_timestamp(void) 1403 { 1404 u32 secs; 1405 u32 msecs; 1406 struct timespec64 ts; 1407 1408 ktime_get_real_ts64(&ts); 1409 1410 /* Get secs since midnight. */ 1411 (void)div_u64_rem(ts.tv_sec, SECONDS_PER_DAY, &secs); 1412 /* Convert to msecs. */ 1413 msecs = secs * MSEC_PER_SEC; 1414 /* Convert nsec to msec. */ 1415 msecs += (u32)ts.tv_nsec / NSEC_PER_MSEC; 1416 1417 /* Convert to network byte order. */ 1418 return htonl(msecs); 1419 } 1420 EXPORT_SYMBOL(inet_current_timestamp); 1421 1422 int inet_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len) 1423 { 1424 if (sk->sk_family == AF_INET) 1425 return ip_recv_error(sk, msg, len, addr_len); 1426 #if IS_ENABLED(CONFIG_IPV6) 1427 if (sk->sk_family == AF_INET6) 1428 return pingv6_ops.ipv6_recv_error(sk, msg, len, addr_len); 1429 #endif 1430 return -EINVAL; 1431 } 1432 1433 static int inet_gro_complete(struct sk_buff *skb, int nhoff) 1434 { 1435 __be16 newlen = htons(skb->len - nhoff); 1436 struct iphdr *iph = (struct iphdr *)(skb->data + nhoff); 1437 const struct net_offload *ops; 1438 int proto = iph->protocol; 1439 int err = -ENOSYS; 1440 1441 if (skb->encapsulation) 1442 skb_set_inner_network_header(skb, nhoff); 1443 1444 csum_replace2(&iph->check, iph->tot_len, newlen); 1445 iph->tot_len = newlen; 1446 1447 rcu_read_lock(); 1448 ops = rcu_dereference(inet_offloads[proto]); 1449 if (WARN_ON(!ops || !ops->callbacks.gro_complete)) 1450 goto out_unlock; 1451 1452 /* Only need to add sizeof(*iph) to get to the next hdr below 1453 * because any hdr with option will have been flushed in 1454 * inet_gro_receive(). 1455 */ 1456 err = ops->callbacks.gro_complete(skb, nhoff + sizeof(*iph)); 1457 1458 out_unlock: 1459 rcu_read_unlock(); 1460 1461 return err; 1462 } 1463 1464 static int ipip_gro_complete(struct sk_buff *skb, int nhoff) 1465 { 1466 skb->encapsulation = 1; 1467 skb_shinfo(skb)->gso_type |= SKB_GSO_IPIP; 1468 return inet_gro_complete(skb, nhoff); 1469 } 1470 1471 int inet_ctl_sock_create(struct sock **sk, unsigned short family, 1472 unsigned short type, unsigned char protocol, 1473 struct net *net) 1474 { 1475 struct socket *sock; 1476 int rc = sock_create_kern(net, family, type, protocol, &sock); 1477 1478 if (rc == 0) { 1479 *sk = sock->sk; 1480 (*sk)->sk_allocation = GFP_ATOMIC; 1481 /* 1482 * Unhash it so that IP input processing does not even see it, 1483 * we do not wish this socket to see incoming packets. 1484 */ 1485 (*sk)->sk_prot->unhash(*sk); 1486 } 1487 return rc; 1488 } 1489 EXPORT_SYMBOL_GPL(inet_ctl_sock_create); 1490 1491 u64 snmp_get_cpu_field(void __percpu *mib, int cpu, int offt) 1492 { 1493 return *(((unsigned long *)per_cpu_ptr(mib, cpu)) + offt); 1494 } 1495 EXPORT_SYMBOL_GPL(snmp_get_cpu_field); 1496 1497 unsigned long snmp_fold_field(void __percpu *mib, int offt) 1498 { 1499 unsigned long res = 0; 1500 int i; 1501 1502 for_each_possible_cpu(i) 1503 res += snmp_get_cpu_field(mib, i, offt); 1504 return res; 1505 } 1506 EXPORT_SYMBOL_GPL(snmp_fold_field); 1507 1508 #if BITS_PER_LONG==32 1509 1510 u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offt, 1511 size_t syncp_offset) 1512 { 1513 void *bhptr; 1514 struct u64_stats_sync *syncp; 1515 u64 v; 1516 unsigned int start; 1517 1518 bhptr = per_cpu_ptr(mib, cpu); 1519 syncp = (struct u64_stats_sync *)(bhptr + syncp_offset); 1520 do { 1521 start = u64_stats_fetch_begin_irq(syncp); 1522 v = *(((u64 *)bhptr) + offt); 1523 } while (u64_stats_fetch_retry_irq(syncp, start)); 1524 1525 return v; 1526 } 1527 EXPORT_SYMBOL_GPL(snmp_get_cpu_field64); 1528 1529 u64 snmp_fold_field64(void __percpu *mib, int offt, size_t syncp_offset) 1530 { 1531 u64 res = 0; 1532 int cpu; 1533 1534 for_each_possible_cpu(cpu) { 1535 res += snmp_get_cpu_field64(mib, cpu, offt, syncp_offset); 1536 } 1537 return res; 1538 } 1539 EXPORT_SYMBOL_GPL(snmp_fold_field64); 1540 #endif 1541 1542 #ifdef CONFIG_IP_MULTICAST 1543 static const struct net_protocol igmp_protocol = { 1544 .handler = igmp_rcv, 1545 .netns_ok = 1, 1546 }; 1547 #endif 1548 1549 static const struct net_protocol tcp_protocol = { 1550 .early_demux = tcp_v4_early_demux, 1551 .handler = tcp_v4_rcv, 1552 .err_handler = tcp_v4_err, 1553 .no_policy = 1, 1554 .netns_ok = 1, 1555 .icmp_strict_tag_validation = 1, 1556 }; 1557 1558 static const struct net_protocol udp_protocol = { 1559 .early_demux = udp_v4_early_demux, 1560 .handler = udp_rcv, 1561 .err_handler = udp_err, 1562 .no_policy = 1, 1563 .netns_ok = 1, 1564 }; 1565 1566 static const struct net_protocol icmp_protocol = { 1567 .handler = icmp_rcv, 1568 .err_handler = icmp_err, 1569 .no_policy = 1, 1570 .netns_ok = 1, 1571 }; 1572 1573 static __net_init int ipv4_mib_init_net(struct net *net) 1574 { 1575 int i; 1576 1577 net->mib.tcp_statistics = alloc_percpu(struct tcp_mib); 1578 if (!net->mib.tcp_statistics) 1579 goto err_tcp_mib; 1580 net->mib.ip_statistics = alloc_percpu(struct ipstats_mib); 1581 if (!net->mib.ip_statistics) 1582 goto err_ip_mib; 1583 1584 for_each_possible_cpu(i) { 1585 struct ipstats_mib *af_inet_stats; 1586 af_inet_stats = per_cpu_ptr(net->mib.ip_statistics, i); 1587 u64_stats_init(&af_inet_stats->syncp); 1588 } 1589 1590 net->mib.net_statistics = alloc_percpu(struct linux_mib); 1591 if (!net->mib.net_statistics) 1592 goto err_net_mib; 1593 net->mib.udp_statistics = alloc_percpu(struct udp_mib); 1594 if (!net->mib.udp_statistics) 1595 goto err_udp_mib; 1596 net->mib.udplite_statistics = alloc_percpu(struct udp_mib); 1597 if (!net->mib.udplite_statistics) 1598 goto err_udplite_mib; 1599 net->mib.icmp_statistics = alloc_percpu(struct icmp_mib); 1600 if (!net->mib.icmp_statistics) 1601 goto err_icmp_mib; 1602 net->mib.icmpmsg_statistics = kzalloc(sizeof(struct icmpmsg_mib), 1603 GFP_KERNEL); 1604 if (!net->mib.icmpmsg_statistics) 1605 goto err_icmpmsg_mib; 1606 1607 tcp_mib_init(net); 1608 return 0; 1609 1610 err_icmpmsg_mib: 1611 free_percpu(net->mib.icmp_statistics); 1612 err_icmp_mib: 1613 free_percpu(net->mib.udplite_statistics); 1614 err_udplite_mib: 1615 free_percpu(net->mib.udp_statistics); 1616 err_udp_mib: 1617 free_percpu(net->mib.net_statistics); 1618 err_net_mib: 1619 free_percpu(net->mib.ip_statistics); 1620 err_ip_mib: 1621 free_percpu(net->mib.tcp_statistics); 1622 err_tcp_mib: 1623 return -ENOMEM; 1624 } 1625 1626 static __net_exit void ipv4_mib_exit_net(struct net *net) 1627 { 1628 kfree(net->mib.icmpmsg_statistics); 1629 free_percpu(net->mib.icmp_statistics); 1630 free_percpu(net->mib.udplite_statistics); 1631 free_percpu(net->mib.udp_statistics); 1632 free_percpu(net->mib.net_statistics); 1633 free_percpu(net->mib.ip_statistics); 1634 free_percpu(net->mib.tcp_statistics); 1635 } 1636 1637 static __net_initdata struct pernet_operations ipv4_mib_ops = { 1638 .init = ipv4_mib_init_net, 1639 .exit = ipv4_mib_exit_net, 1640 }; 1641 1642 static int __init init_ipv4_mibs(void) 1643 { 1644 return register_pernet_subsys(&ipv4_mib_ops); 1645 } 1646 1647 static __net_init int inet_init_net(struct net *net) 1648 { 1649 /* 1650 * Set defaults for local port range 1651 */ 1652 seqlock_init(&net->ipv4.ip_local_ports.lock); 1653 net->ipv4.ip_local_ports.range[0] = 32768; 1654 net->ipv4.ip_local_ports.range[1] = 60999; 1655 1656 seqlock_init(&net->ipv4.ping_group_range.lock); 1657 /* 1658 * Sane defaults - nobody may create ping sockets. 1659 * Boot scripts should set this to distro-specific group. 1660 */ 1661 net->ipv4.ping_group_range.range[0] = make_kgid(&init_user_ns, 1); 1662 net->ipv4.ping_group_range.range[1] = make_kgid(&init_user_ns, 0); 1663 return 0; 1664 } 1665 1666 static __net_exit void inet_exit_net(struct net *net) 1667 { 1668 } 1669 1670 static __net_initdata struct pernet_operations af_inet_ops = { 1671 .init = inet_init_net, 1672 .exit = inet_exit_net, 1673 }; 1674 1675 static int __init init_inet_pernet_ops(void) 1676 { 1677 return register_pernet_subsys(&af_inet_ops); 1678 } 1679 1680 static int ipv4_proc_init(void); 1681 1682 /* 1683 * IP protocol layer initialiser 1684 */ 1685 1686 static struct packet_offload ip_packet_offload __read_mostly = { 1687 .type = cpu_to_be16(ETH_P_IP), 1688 .callbacks = { 1689 .gso_segment = inet_gso_segment, 1690 .gro_receive = inet_gro_receive, 1691 .gro_complete = inet_gro_complete, 1692 }, 1693 }; 1694 1695 static const struct net_offload ipip_offload = { 1696 .callbacks = { 1697 .gso_segment = inet_gso_segment, 1698 .gro_receive = ipip_gro_receive, 1699 .gro_complete = ipip_gro_complete, 1700 }, 1701 }; 1702 1703 static int __init ipv4_offload_init(void) 1704 { 1705 /* 1706 * Add offloads 1707 */ 1708 if (udpv4_offload_init() < 0) 1709 pr_crit("%s: Cannot add UDP protocol offload\n", __func__); 1710 if (tcpv4_offload_init() < 0) 1711 pr_crit("%s: Cannot add TCP protocol offload\n", __func__); 1712 1713 dev_add_offload(&ip_packet_offload); 1714 inet_add_offload(&ipip_offload, IPPROTO_IPIP); 1715 return 0; 1716 } 1717 1718 fs_initcall(ipv4_offload_init); 1719 1720 static struct packet_type ip_packet_type __read_mostly = { 1721 .type = cpu_to_be16(ETH_P_IP), 1722 .func = ip_rcv, 1723 }; 1724 1725 static int __init inet_init(void) 1726 { 1727 struct inet_protosw *q; 1728 struct list_head *r; 1729 int rc = -EINVAL; 1730 1731 sock_skb_cb_check_size(sizeof(struct inet_skb_parm)); 1732 1733 rc = proto_register(&tcp_prot, 1); 1734 if (rc) 1735 goto out; 1736 1737 rc = proto_register(&udp_prot, 1); 1738 if (rc) 1739 goto out_unregister_tcp_proto; 1740 1741 rc = proto_register(&raw_prot, 1); 1742 if (rc) 1743 goto out_unregister_udp_proto; 1744 1745 rc = proto_register(&ping_prot, 1); 1746 if (rc) 1747 goto out_unregister_raw_proto; 1748 1749 /* 1750 * Tell SOCKET that we are alive... 1751 */ 1752 1753 (void)sock_register(&inet_family_ops); 1754 1755 #ifdef CONFIG_SYSCTL 1756 ip_static_sysctl_init(); 1757 #endif 1758 1759 /* 1760 * Add all the base protocols. 1761 */ 1762 1763 if (inet_add_protocol(&icmp_protocol, IPPROTO_ICMP) < 0) 1764 pr_crit("%s: Cannot add ICMP protocol\n", __func__); 1765 if (inet_add_protocol(&udp_protocol, IPPROTO_UDP) < 0) 1766 pr_crit("%s: Cannot add UDP protocol\n", __func__); 1767 if (inet_add_protocol(&tcp_protocol, IPPROTO_TCP) < 0) 1768 pr_crit("%s: Cannot add TCP protocol\n", __func__); 1769 #ifdef CONFIG_IP_MULTICAST 1770 if (inet_add_protocol(&igmp_protocol, IPPROTO_IGMP) < 0) 1771 pr_crit("%s: Cannot add IGMP protocol\n", __func__); 1772 #endif 1773 1774 /* Register the socket-side information for inet_create. */ 1775 for (r = &inetsw[0]; r < &inetsw[SOCK_MAX]; ++r) 1776 INIT_LIST_HEAD(r); 1777 1778 for (q = inetsw_array; q < &inetsw_array[INETSW_ARRAY_LEN]; ++q) 1779 inet_register_protosw(q); 1780 1781 /* 1782 * Set the ARP module up 1783 */ 1784 1785 arp_init(); 1786 1787 /* 1788 * Set the IP module up 1789 */ 1790 1791 ip_init(); 1792 1793 tcp_v4_init(); 1794 1795 /* Setup TCP slab cache for open requests. */ 1796 tcp_init(); 1797 1798 /* Setup UDP memory threshold */ 1799 udp_init(); 1800 1801 /* Add UDP-Lite (RFC 3828) */ 1802 udplite4_register(); 1803 1804 ping_init(); 1805 1806 /* 1807 * Set the ICMP layer up 1808 */ 1809 1810 if (icmp_init() < 0) 1811 panic("Failed to create the ICMP control socket.\n"); 1812 1813 /* 1814 * Initialise the multicast router 1815 */ 1816 #if defined(CONFIG_IP_MROUTE) 1817 if (ip_mr_init()) 1818 pr_crit("%s: Cannot init ipv4 mroute\n", __func__); 1819 #endif 1820 1821 if (init_inet_pernet_ops()) 1822 pr_crit("%s: Cannot init ipv4 inet pernet ops\n", __func__); 1823 /* 1824 * Initialise per-cpu ipv4 mibs 1825 */ 1826 1827 if (init_ipv4_mibs()) 1828 pr_crit("%s: Cannot init ipv4 mibs\n", __func__); 1829 1830 ipv4_proc_init(); 1831 1832 ipfrag_init(); 1833 1834 dev_add_pack(&ip_packet_type); 1835 1836 ip_tunnel_core_init(); 1837 1838 rc = 0; 1839 out: 1840 return rc; 1841 out_unregister_raw_proto: 1842 proto_unregister(&raw_prot); 1843 out_unregister_udp_proto: 1844 proto_unregister(&udp_prot); 1845 out_unregister_tcp_proto: 1846 proto_unregister(&tcp_prot); 1847 goto out; 1848 } 1849 1850 fs_initcall(inet_init); 1851 1852 /* ------------------------------------------------------------------------ */ 1853 1854 #ifdef CONFIG_PROC_FS 1855 static int __init ipv4_proc_init(void) 1856 { 1857 int rc = 0; 1858 1859 if (raw_proc_init()) 1860 goto out_raw; 1861 if (tcp4_proc_init()) 1862 goto out_tcp; 1863 if (udp4_proc_init()) 1864 goto out_udp; 1865 if (ping_proc_init()) 1866 goto out_ping; 1867 if (ip_misc_proc_init()) 1868 goto out_misc; 1869 out: 1870 return rc; 1871 out_misc: 1872 ping_proc_exit(); 1873 out_ping: 1874 udp4_proc_exit(); 1875 out_udp: 1876 tcp4_proc_exit(); 1877 out_tcp: 1878 raw_proc_exit(); 1879 out_raw: 1880 rc = -ENOMEM; 1881 goto out; 1882 } 1883 1884 #else /* CONFIG_PROC_FS */ 1885 static int __init ipv4_proc_init(void) 1886 { 1887 return 0; 1888 } 1889 #endif /* CONFIG_PROC_FS */ 1890 1891 MODULE_ALIAS_NETPROTO(PF_INET); 1892 1893