blob: 20f52b5f5dea165ef8bb28b01332573b0dfe5c02 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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 * Version: $Id: af_inet.c,v 1.137 2002/02/01 22:01:03 davem Exp $
9 *
Jesper Juhl02c30a82005-05-05 16:16:16 -070010 * Authors: Ross Biro
Linus Torvalds1da177e2005-04-16 15:20:36 -070011 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12 * Florian La Roche, <flla@stud.uni-sb.de>
13 * Alan Cox, <A.Cox@swansea.ac.uk>
14 *
15 * Changes (see also sock.c)
16 *
17 * piggy,
18 * Karl Knutson : Socket protocol table
19 * A.N.Kuznetsov : Socket death error in accept().
20 * John Richardson : Fix non blocking error in connect()
21 * so sockets that fail to connect
22 * don't return -EINPROGRESS.
23 * Alan Cox : Asynchronous I/O support
24 * Alan Cox : Keep correct socket pointer on sock
25 * structures
26 * when accept() ed
27 * Alan Cox : Semantics of SO_LINGER aren't state
28 * moved to close when you look carefully.
29 * With this fixed and the accept bug fixed
30 * some RPC stuff seems happier.
31 * Niibe Yutaka : 4.4BSD style write async I/O
32 * Alan Cox,
33 * Tony Gale : Fixed reuse semantics.
34 * Alan Cox : bind() shouldn't abort existing but dead
35 * sockets. Stops FTP netin:.. I hope.
36 * Alan Cox : bind() works correctly for RAW sockets.
37 * Note that FreeBSD at least was broken
38 * in this respect so be careful with
39 * compatibility tests...
40 * Alan Cox : routing cache support
41 * Alan Cox : memzero the socket structure for
42 * compactness.
43 * Matt Day : nonblock connect error handler
44 * Alan Cox : Allow large numbers of pending sockets
45 * (eg for big web sites), but only if
46 * specifically application requested.
47 * Alan Cox : New buffering throughout IP. Used
48 * dumbly.
49 * Alan Cox : New buffering now used smartly.
50 * Alan Cox : BSD rather than common sense
51 * interpretation of listen.
52 * Germano Caronni : Assorted small races.
53 * Alan Cox : sendmsg/recvmsg basic support.
54 * Alan Cox : Only sendmsg/recvmsg now supported.
55 * Alan Cox : Locked down bind (see security list).
56 * Alan Cox : Loosened bind a little.
57 * Mike McLagan : ADD/DEL DLCI Ioctls
58 * Willy Konynenberg : Transparent proxying support.
59 * David S. Miller : New socket lookup architecture.
60 * Some other random speedups.
61 * Cyrus Durgin : Cleaned up file for kmod hacks.
62 * Andi Kleen : Fix inet_stream_connect TCP race.
63 *
64 * This program is free software; you can redistribute it and/or
65 * modify it under the terms of the GNU General Public License
66 * as published by the Free Software Foundation; either version
67 * 2 of the License, or (at your option) any later version.
68 */
69
70#include <linux/config.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>
Linus Torvalds1da177e2005-04-16 15:20:36 -070076#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/fcntl.h>
83#include <linux/mm.h>
84#include <linux/interrupt.h>
85#include <linux/stat.h>
86#include <linux/init.h>
87#include <linux/poll.h>
88#include <linux/netfilter_ipv4.h>
89
90#include <asm/uaccess.h>
91#include <asm/system.h>
92
93#include <linux/smp_lock.h>
94#include <linux/inet.h>
95#include <linux/igmp.h>
96#include <linux/netdevice.h>
97#include <net/ip.h>
98#include <net/protocol.h>
99#include <net/arp.h>
100#include <net/route.h>
101#include <net/ip_fib.h>
Arnaldo Carvalho de Melo295f7322005-08-09 20:11:56 -0700102#include <net/inet_connection_sock.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103#include <net/tcp.h>
104#include <net/udp.h>
105#include <linux/skbuff.h>
106#include <net/sock.h>
107#include <net/raw.h>
108#include <net/icmp.h>
109#include <net/ipip.h>
110#include <net/inet_common.h>
111#include <net/xfrm.h>
112#ifdef CONFIG_IP_MROUTE
113#include <linux/mroute.h>
114#endif
115
116DEFINE_SNMP_STAT(struct linux_mib, net_statistics);
117
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118extern void ip_mc_drop_socket(struct sock *sk);
119
120/* The inetsw table contains everything that inet_create needs to
121 * build a new socket.
122 */
123static struct list_head inetsw[SOCK_MAX];
124static DEFINE_SPINLOCK(inetsw_lock);
125
126/* New destruction routine */
127
128void inet_sock_destruct(struct sock *sk)
129{
130 struct inet_sock *inet = inet_sk(sk);
131
132 __skb_queue_purge(&sk->sk_receive_queue);
133 __skb_queue_purge(&sk->sk_error_queue);
134
135 if (sk->sk_type == SOCK_STREAM && sk->sk_state != TCP_CLOSE) {
136 printk("Attempt to release TCP socket in state %d %p\n",
137 sk->sk_state, sk);
138 return;
139 }
140 if (!sock_flag(sk, SOCK_DEAD)) {
141 printk("Attempt to release alive inet socket %p\n", sk);
142 return;
143 }
144
145 BUG_TRAP(!atomic_read(&sk->sk_rmem_alloc));
146 BUG_TRAP(!atomic_read(&sk->sk_wmem_alloc));
147 BUG_TRAP(!sk->sk_wmem_queued);
148 BUG_TRAP(!sk->sk_forward_alloc);
149
150 if (inet->opt)
151 kfree(inet->opt);
152 dst_release(sk->sk_dst_cache);
Arnaldo Carvalho de Meloe6848972005-08-09 19:45:38 -0700153 sk_refcnt_debug_dec(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154}
155
156/*
157 * The routines beyond this point handle the behaviour of an AF_INET
158 * socket object. Mostly it punts to the subprotocols of IP to do
159 * the work.
160 */
161
162/*
163 * Automatically bind an unbound socket.
164 */
165
166static int inet_autobind(struct sock *sk)
167{
168 struct inet_sock *inet;
169 /* We may need to bind the socket. */
170 lock_sock(sk);
171 inet = inet_sk(sk);
172 if (!inet->num) {
173 if (sk->sk_prot->get_port(sk, 0)) {
174 release_sock(sk);
175 return -EAGAIN;
176 }
177 inet->sport = htons(inet->num);
178 }
179 release_sock(sk);
180 return 0;
181}
182
183/*
184 * Move a socket into listening state.
185 */
186int inet_listen(struct socket *sock, int backlog)
187{
188 struct sock *sk = sock->sk;
189 unsigned char old_state;
190 int err;
191
192 lock_sock(sk);
193
194 err = -EINVAL;
195 if (sock->state != SS_UNCONNECTED || sock->type != SOCK_STREAM)
196 goto out;
197
198 old_state = sk->sk_state;
199 if (!((1 << old_state) & (TCPF_CLOSE | TCPF_LISTEN)))
200 goto out;
201
202 /* Really, if the socket is already in listen state
203 * we can only allow the backlog to be adjusted.
204 */
205 if (old_state != TCP_LISTEN) {
Arnaldo Carvalho de Melo0a5578c2005-08-09 20:11:41 -0700206 err = inet_csk_listen_start(sk, TCP_SYNQ_HSIZE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700207 if (err)
208 goto out;
209 }
210 sk->sk_max_ack_backlog = backlog;
211 err = 0;
212
213out:
214 release_sock(sk);
215 return err;
216}
217
218/*
219 * Create an inet socket.
220 */
221
222static int inet_create(struct socket *sock, int protocol)
223{
224 struct sock *sk;
225 struct list_head *p;
226 struct inet_protosw *answer;
227 struct inet_sock *inet;
228 struct proto *answer_prot;
229 unsigned char answer_flags;
230 char answer_no_check;
Arnaldo Carvalho de Melobb97d312005-08-09 20:19:14 -0700231 int try_loading_module = 0;
232 int err = -ESOCKTNOSUPPORT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700233
234 sock->state = SS_UNCONNECTED;
235
236 /* Look for the requested type/protocol pair. */
237 answer = NULL;
Arnaldo Carvalho de Melobb97d312005-08-09 20:19:14 -0700238lookup_protocol:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700239 rcu_read_lock();
240 list_for_each_rcu(p, &inetsw[sock->type]) {
241 answer = list_entry(p, struct inet_protosw, list);
242
243 /* Check the non-wild match. */
244 if (protocol == answer->protocol) {
245 if (protocol != IPPROTO_IP)
246 break;
247 } else {
248 /* Check for the two wild cases. */
249 if (IPPROTO_IP == protocol) {
250 protocol = answer->protocol;
251 break;
252 }
253 if (IPPROTO_IP == answer->protocol)
254 break;
255 }
256 answer = NULL;
257 }
258
Arnaldo Carvalho de Melobb97d312005-08-09 20:19:14 -0700259 if (unlikely(answer == NULL)) {
260 if (try_loading_module < 2) {
261 rcu_read_unlock();
262 /*
263 * Be more specific, e.g. net-pf-2-proto-132-type-1
264 * (net-pf-PF_INET-proto-IPPROTO_SCTP-type-SOCK_STREAM)
265 */
266 if (++try_loading_module == 1)
267 request_module("net-pf-%d-proto-%d-type-%d",
268 PF_INET, protocol, sock->type);
269 /*
270 * Fall back to generic, e.g. net-pf-2-proto-132
271 * (net-pf-PF_INET-proto-IPPROTO_SCTP)
272 */
273 else
274 request_module("net-pf-%d-proto-%d",
275 PF_INET, protocol);
276 goto lookup_protocol;
277 } else
278 goto out_rcu_unlock;
279 }
280
Linus Torvalds1da177e2005-04-16 15:20:36 -0700281 err = -EPERM;
282 if (answer->capability > 0 && !capable(answer->capability))
283 goto out_rcu_unlock;
284 err = -EPROTONOSUPPORT;
285 if (!protocol)
286 goto out_rcu_unlock;
287
288 sock->ops = answer->ops;
289 answer_prot = answer->prot;
290 answer_no_check = answer->no_check;
291 answer_flags = answer->flags;
292 rcu_read_unlock();
293
294 BUG_TRAP(answer_prot->slab != NULL);
295
296 err = -ENOBUFS;
297 sk = sk_alloc(PF_INET, GFP_KERNEL, answer_prot, 1);
298 if (sk == NULL)
299 goto out;
300
301 err = 0;
302 sk->sk_no_check = answer_no_check;
303 if (INET_PROTOSW_REUSE & answer_flags)
304 sk->sk_reuse = 1;
305
306 inet = inet_sk(sk);
307
308 if (SOCK_RAW == sock->type) {
309 inet->num = protocol;
310 if (IPPROTO_RAW == protocol)
311 inet->hdrincl = 1;
312 }
313
314 if (ipv4_config.no_pmtu_disc)
315 inet->pmtudisc = IP_PMTUDISC_DONT;
316 else
317 inet->pmtudisc = IP_PMTUDISC_WANT;
318
319 inet->id = 0;
320
321 sock_init_data(sock, sk);
322
323 sk->sk_destruct = inet_sock_destruct;
324 sk->sk_family = PF_INET;
325 sk->sk_protocol = protocol;
326 sk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
327
328 inet->uc_ttl = -1;
329 inet->mc_loop = 1;
330 inet->mc_ttl = 1;
331 inet->mc_index = 0;
332 inet->mc_list = NULL;
333
Arnaldo Carvalho de Meloe6848972005-08-09 19:45:38 -0700334 sk_refcnt_debug_inc(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700335
336 if (inet->num) {
337 /* It assumes that any protocol which allows
338 * the user to assign a number at socket
339 * creation time automatically
340 * shares.
341 */
342 inet->sport = htons(inet->num);
343 /* Add to protocol hash chains. */
344 sk->sk_prot->hash(sk);
345 }
346
347 if (sk->sk_prot->init) {
348 err = sk->sk_prot->init(sk);
349 if (err)
350 sk_common_release(sk);
351 }
352out:
353 return err;
354out_rcu_unlock:
355 rcu_read_unlock();
356 goto out;
357}
358
359
360/*
361 * The peer socket should always be NULL (or else). When we call this
362 * function we are destroying the object and from then on nobody
363 * should refer to it.
364 */
365int inet_release(struct socket *sock)
366{
367 struct sock *sk = sock->sk;
368
369 if (sk) {
370 long timeout;
371
372 /* Applications forget to leave groups before exiting */
373 ip_mc_drop_socket(sk);
374
375 /* If linger is set, we don't return until the close
376 * is complete. Otherwise we return immediately. The
377 * actually closing is done the same either way.
378 *
379 * If the close is due to the process exiting, we never
380 * linger..
381 */
382 timeout = 0;
383 if (sock_flag(sk, SOCK_LINGER) &&
384 !(current->flags & PF_EXITING))
385 timeout = sk->sk_lingertime;
386 sock->sk = NULL;
387 sk->sk_prot->close(sk, timeout);
388 }
389 return 0;
390}
391
392/* It is off by default, see below. */
393int sysctl_ip_nonlocal_bind;
394
395int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
396{
397 struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
398 struct sock *sk = sock->sk;
399 struct inet_sock *inet = inet_sk(sk);
400 unsigned short snum;
401 int chk_addr_ret;
402 int err;
403
404 /* If the socket has its own bind function then use it. (RAW) */
405 if (sk->sk_prot->bind) {
406 err = sk->sk_prot->bind(sk, uaddr, addr_len);
407 goto out;
408 }
409 err = -EINVAL;
410 if (addr_len < sizeof(struct sockaddr_in))
411 goto out;
412
413 chk_addr_ret = inet_addr_type(addr->sin_addr.s_addr);
414
415 /* Not specified by any standard per-se, however it breaks too
416 * many applications when removed. It is unfortunate since
417 * allowing applications to make a non-local bind solves
418 * several problems with systems using dynamic addressing.
419 * (ie. your servers still start up even if your ISDN link
420 * is temporarily down)
421 */
422 err = -EADDRNOTAVAIL;
423 if (!sysctl_ip_nonlocal_bind &&
424 !inet->freebind &&
425 addr->sin_addr.s_addr != INADDR_ANY &&
426 chk_addr_ret != RTN_LOCAL &&
427 chk_addr_ret != RTN_MULTICAST &&
428 chk_addr_ret != RTN_BROADCAST)
429 goto out;
430
431 snum = ntohs(addr->sin_port);
432 err = -EACCES;
433 if (snum && snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
434 goto out;
435
436 /* We keep a pair of addresses. rcv_saddr is the one
437 * used by hash lookups, and saddr is used for transmit.
438 *
439 * In the BSD API these are the same except where it
440 * would be illegal to use them (multicast/broadcast) in
441 * which case the sending device address is used.
442 */
443 lock_sock(sk);
444
445 /* Check these errors (active socket, double bind). */
446 err = -EINVAL;
447 if (sk->sk_state != TCP_CLOSE || inet->num)
448 goto out_release_sock;
449
450 inet->rcv_saddr = inet->saddr = addr->sin_addr.s_addr;
451 if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST)
452 inet->saddr = 0; /* Use device */
453
454 /* Make sure we are allowed to bind here. */
455 if (sk->sk_prot->get_port(sk, snum)) {
456 inet->saddr = inet->rcv_saddr = 0;
457 err = -EADDRINUSE;
458 goto out_release_sock;
459 }
460
461 if (inet->rcv_saddr)
462 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
463 if (snum)
464 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
465 inet->sport = htons(inet->num);
466 inet->daddr = 0;
467 inet->dport = 0;
468 sk_dst_reset(sk);
469 err = 0;
470out_release_sock:
471 release_sock(sk);
472out:
473 return err;
474}
475
476int inet_dgram_connect(struct socket *sock, struct sockaddr * uaddr,
477 int addr_len, int flags)
478{
479 struct sock *sk = sock->sk;
480
481 if (uaddr->sa_family == AF_UNSPEC)
482 return sk->sk_prot->disconnect(sk, flags);
483
484 if (!inet_sk(sk)->num && inet_autobind(sk))
485 return -EAGAIN;
486 return sk->sk_prot->connect(sk, (struct sockaddr *)uaddr, addr_len);
487}
488
489static long inet_wait_for_connect(struct sock *sk, long timeo)
490{
491 DEFINE_WAIT(wait);
492
493 prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
494
495 /* Basic assumption: if someone sets sk->sk_err, he _must_
496 * change state of the socket from TCP_SYN_*.
497 * Connect() does not allow to get error notifications
498 * without closing the socket.
499 */
500 while ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
501 release_sock(sk);
502 timeo = schedule_timeout(timeo);
503 lock_sock(sk);
504 if (signal_pending(current) || !timeo)
505 break;
506 prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
507 }
508 finish_wait(sk->sk_sleep, &wait);
509 return timeo;
510}
511
512/*
513 * Connect to a remote host. There is regrettably still a little
514 * TCP 'magic' in here.
515 */
516int inet_stream_connect(struct socket *sock, struct sockaddr *uaddr,
517 int addr_len, int flags)
518{
519 struct sock *sk = sock->sk;
520 int err;
521 long timeo;
522
523 lock_sock(sk);
524
525 if (uaddr->sa_family == AF_UNSPEC) {
526 err = sk->sk_prot->disconnect(sk, flags);
527 sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
528 goto out;
529 }
530
531 switch (sock->state) {
532 default:
533 err = -EINVAL;
534 goto out;
535 case SS_CONNECTED:
536 err = -EISCONN;
537 goto out;
538 case SS_CONNECTING:
539 err = -EALREADY;
540 /* Fall out of switch with err, set for this state */
541 break;
542 case SS_UNCONNECTED:
543 err = -EISCONN;
544 if (sk->sk_state != TCP_CLOSE)
545 goto out;
546
547 err = sk->sk_prot->connect(sk, uaddr, addr_len);
548 if (err < 0)
549 goto out;
550
551 sock->state = SS_CONNECTING;
552
553 /* Just entered SS_CONNECTING state; the only
554 * difference is that return value in non-blocking
555 * case is EINPROGRESS, rather than EALREADY.
556 */
557 err = -EINPROGRESS;
558 break;
559 }
560
561 timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
562
563 if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
564 /* Error code is set above */
565 if (!timeo || !inet_wait_for_connect(sk, timeo))
566 goto out;
567
568 err = sock_intr_errno(timeo);
569 if (signal_pending(current))
570 goto out;
571 }
572
573 /* Connection was closed by RST, timeout, ICMP error
574 * or another process disconnected us.
575 */
576 if (sk->sk_state == TCP_CLOSE)
577 goto sock_error;
578
579 /* sk->sk_err may be not zero now, if RECVERR was ordered by user
580 * and error was received after socket entered established state.
581 * Hence, it is handled normally after connect() return successfully.
582 */
583
584 sock->state = SS_CONNECTED;
585 err = 0;
586out:
587 release_sock(sk);
588 return err;
589
590sock_error:
591 err = sock_error(sk) ? : -ECONNABORTED;
592 sock->state = SS_UNCONNECTED;
593 if (sk->sk_prot->disconnect(sk, flags))
594 sock->state = SS_DISCONNECTING;
595 goto out;
596}
597
598/*
599 * Accept a pending connection. The TCP layer now gives BSD semantics.
600 */
601
602int inet_accept(struct socket *sock, struct socket *newsock, int flags)
603{
604 struct sock *sk1 = sock->sk;
605 int err = -EINVAL;
606 struct sock *sk2 = sk1->sk_prot->accept(sk1, flags, &err);
607
608 if (!sk2)
609 goto do_err;
610
611 lock_sock(sk2);
612
613 BUG_TRAP((1 << sk2->sk_state) &
614 (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT | TCPF_CLOSE));
615
616 sock_graft(sk2, newsock);
617
618 newsock->state = SS_CONNECTED;
619 err = 0;
620 release_sock(sk2);
621do_err:
622 return err;
623}
624
625
626/*
627 * This does both peername and sockname.
628 */
629int inet_getname(struct socket *sock, struct sockaddr *uaddr,
630 int *uaddr_len, int peer)
631{
632 struct sock *sk = sock->sk;
633 struct inet_sock *inet = inet_sk(sk);
634 struct sockaddr_in *sin = (struct sockaddr_in *)uaddr;
635
636 sin->sin_family = AF_INET;
637 if (peer) {
638 if (!inet->dport ||
639 (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
640 peer == 1))
641 return -ENOTCONN;
642 sin->sin_port = inet->dport;
643 sin->sin_addr.s_addr = inet->daddr;
644 } else {
645 __u32 addr = inet->rcv_saddr;
646 if (!addr)
647 addr = inet->saddr;
648 sin->sin_port = inet->sport;
649 sin->sin_addr.s_addr = addr;
650 }
651 memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
652 *uaddr_len = sizeof(*sin);
653 return 0;
654}
655
656int inet_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
657 size_t size)
658{
659 struct sock *sk = sock->sk;
660
661 /* We may need to bind the socket. */
662 if (!inet_sk(sk)->num && inet_autobind(sk))
663 return -EAGAIN;
664
665 return sk->sk_prot->sendmsg(iocb, sk, msg, size);
666}
667
668
669static ssize_t inet_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
670{
671 struct sock *sk = sock->sk;
672
673 /* We may need to bind the socket. */
674 if (!inet_sk(sk)->num && inet_autobind(sk))
675 return -EAGAIN;
676
677 if (sk->sk_prot->sendpage)
678 return sk->sk_prot->sendpage(sk, page, offset, size, flags);
679 return sock_no_sendpage(sock, page, offset, size, flags);
680}
681
682
683int inet_shutdown(struct socket *sock, int how)
684{
685 struct sock *sk = sock->sk;
686 int err = 0;
687
688 /* This should really check to make sure
689 * the socket is a TCP socket. (WHY AC...)
690 */
691 how++; /* maps 0->1 has the advantage of making bit 1 rcvs and
692 1->2 bit 2 snds.
693 2->3 */
694 if ((how & ~SHUTDOWN_MASK) || !how) /* MAXINT->0 */
695 return -EINVAL;
696
697 lock_sock(sk);
698 if (sock->state == SS_CONNECTING) {
699 if ((1 << sk->sk_state) &
700 (TCPF_SYN_SENT | TCPF_SYN_RECV | TCPF_CLOSE))
701 sock->state = SS_DISCONNECTING;
702 else
703 sock->state = SS_CONNECTED;
704 }
705
706 switch (sk->sk_state) {
707 case TCP_CLOSE:
708 err = -ENOTCONN;
709 /* Hack to wake up other listeners, who can poll for
710 POLLHUP, even on eg. unconnected UDP sockets -- RR */
711 default:
712 sk->sk_shutdown |= how;
713 if (sk->sk_prot->shutdown)
714 sk->sk_prot->shutdown(sk, how);
715 break;
716
717 /* Remaining two branches are temporary solution for missing
718 * close() in multithreaded environment. It is _not_ a good idea,
719 * but we have no choice until close() is repaired at VFS level.
720 */
721 case TCP_LISTEN:
722 if (!(how & RCV_SHUTDOWN))
723 break;
724 /* Fall through */
725 case TCP_SYN_SENT:
726 err = sk->sk_prot->disconnect(sk, O_NONBLOCK);
727 sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
728 break;
729 }
730
731 /* Wake up anyone sleeping in poll. */
732 sk->sk_state_change(sk);
733 release_sock(sk);
734 return err;
735}
736
737/*
738 * ioctl() calls you can issue on an INET socket. Most of these are
739 * device configuration and stuff and very rarely used. Some ioctls
740 * pass on to the socket itself.
741 *
742 * NOTE: I like the idea of a module for the config stuff. ie ifconfig
743 * loads the devconfigure module does its configuring and unloads it.
744 * There's a good 20K of config code hanging around the kernel.
745 */
746
747int inet_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
748{
749 struct sock *sk = sock->sk;
750 int err = 0;
751
752 switch (cmd) {
753 case SIOCGSTAMP:
754 err = sock_get_timestamp(sk, (struct timeval __user *)arg);
755 break;
756 case SIOCADDRT:
757 case SIOCDELRT:
758 case SIOCRTMSG:
759 err = ip_rt_ioctl(cmd, (void __user *)arg);
760 break;
761 case SIOCDARP:
762 case SIOCGARP:
763 case SIOCSARP:
764 err = arp_ioctl(cmd, (void __user *)arg);
765 break;
766 case SIOCGIFADDR:
767 case SIOCSIFADDR:
768 case SIOCGIFBRDADDR:
769 case SIOCSIFBRDADDR:
770 case SIOCGIFNETMASK:
771 case SIOCSIFNETMASK:
772 case SIOCGIFDSTADDR:
773 case SIOCSIFDSTADDR:
774 case SIOCSIFPFLAGS:
775 case SIOCGIFPFLAGS:
776 case SIOCSIFFLAGS:
777 err = devinet_ioctl(cmd, (void __user *)arg);
778 break;
779 default:
780 if (!sk->sk_prot->ioctl ||
781 (err = sk->sk_prot->ioctl(sk, cmd, arg)) ==
782 -ENOIOCTLCMD)
783 err = dev_ioctl(cmd, (void __user *)arg);
784 break;
785 }
786 return err;
787}
788
789struct proto_ops inet_stream_ops = {
790 .family = PF_INET,
791 .owner = THIS_MODULE,
792 .release = inet_release,
793 .bind = inet_bind,
794 .connect = inet_stream_connect,
795 .socketpair = sock_no_socketpair,
796 .accept = inet_accept,
797 .getname = inet_getname,
798 .poll = tcp_poll,
799 .ioctl = inet_ioctl,
800 .listen = inet_listen,
801 .shutdown = inet_shutdown,
802 .setsockopt = sock_common_setsockopt,
803 .getsockopt = sock_common_getsockopt,
804 .sendmsg = inet_sendmsg,
805 .recvmsg = sock_common_recvmsg,
806 .mmap = sock_no_mmap,
807 .sendpage = tcp_sendpage
808};
809
810struct proto_ops inet_dgram_ops = {
811 .family = PF_INET,
812 .owner = THIS_MODULE,
813 .release = inet_release,
814 .bind = inet_bind,
815 .connect = inet_dgram_connect,
816 .socketpair = sock_no_socketpair,
817 .accept = sock_no_accept,
818 .getname = inet_getname,
819 .poll = udp_poll,
820 .ioctl = inet_ioctl,
821 .listen = sock_no_listen,
822 .shutdown = inet_shutdown,
823 .setsockopt = sock_common_setsockopt,
824 .getsockopt = sock_common_getsockopt,
825 .sendmsg = inet_sendmsg,
826 .recvmsg = sock_common_recvmsg,
827 .mmap = sock_no_mmap,
828 .sendpage = inet_sendpage,
829};
830
831/*
832 * For SOCK_RAW sockets; should be the same as inet_dgram_ops but without
833 * udp_poll
834 */
835static struct proto_ops inet_sockraw_ops = {
836 .family = PF_INET,
837 .owner = THIS_MODULE,
838 .release = inet_release,
839 .bind = inet_bind,
840 .connect = inet_dgram_connect,
841 .socketpair = sock_no_socketpair,
842 .accept = sock_no_accept,
843 .getname = inet_getname,
844 .poll = datagram_poll,
845 .ioctl = inet_ioctl,
846 .listen = sock_no_listen,
847 .shutdown = inet_shutdown,
848 .setsockopt = sock_common_setsockopt,
849 .getsockopt = sock_common_getsockopt,
850 .sendmsg = inet_sendmsg,
851 .recvmsg = sock_common_recvmsg,
852 .mmap = sock_no_mmap,
853 .sendpage = inet_sendpage,
854};
855
856static struct net_proto_family inet_family_ops = {
857 .family = PF_INET,
858 .create = inet_create,
859 .owner = THIS_MODULE,
860};
861
862
863extern void tcp_init(void);
864extern void tcp_v4_init(struct net_proto_family *);
865
866/* Upon startup we insert all the elements in inetsw_array[] into
867 * the linked list inetsw.
868 */
869static struct inet_protosw inetsw_array[] =
870{
871 {
872 .type = SOCK_STREAM,
873 .protocol = IPPROTO_TCP,
874 .prot = &tcp_prot,
875 .ops = &inet_stream_ops,
876 .capability = -1,
877 .no_check = 0,
878 .flags = INET_PROTOSW_PERMANENT,
879 },
880
881 {
882 .type = SOCK_DGRAM,
883 .protocol = IPPROTO_UDP,
884 .prot = &udp_prot,
885 .ops = &inet_dgram_ops,
886 .capability = -1,
887 .no_check = UDP_CSUM_DEFAULT,
888 .flags = INET_PROTOSW_PERMANENT,
889 },
890
891
892 {
893 .type = SOCK_RAW,
894 .protocol = IPPROTO_IP, /* wild card */
895 .prot = &raw_prot,
896 .ops = &inet_sockraw_ops,
897 .capability = CAP_NET_RAW,
898 .no_check = UDP_CSUM_DEFAULT,
899 .flags = INET_PROTOSW_REUSE,
900 }
901};
902
903#define INETSW_ARRAY_LEN (sizeof(inetsw_array) / sizeof(struct inet_protosw))
904
905void inet_register_protosw(struct inet_protosw *p)
906{
907 struct list_head *lh;
908 struct inet_protosw *answer;
909 int protocol = p->protocol;
910 struct list_head *last_perm;
911
912 spin_lock_bh(&inetsw_lock);
913
914 if (p->type >= SOCK_MAX)
915 goto out_illegal;
916
917 /* If we are trying to override a permanent protocol, bail. */
918 answer = NULL;
919 last_perm = &inetsw[p->type];
920 list_for_each(lh, &inetsw[p->type]) {
921 answer = list_entry(lh, struct inet_protosw, list);
922
923 /* Check only the non-wild match. */
924 if (INET_PROTOSW_PERMANENT & answer->flags) {
925 if (protocol == answer->protocol)
926 break;
927 last_perm = lh;
928 }
929
930 answer = NULL;
931 }
932 if (answer)
933 goto out_permanent;
934
935 /* Add the new entry after the last permanent entry if any, so that
936 * the new entry does not override a permanent entry when matched with
937 * a wild-card protocol. But it is allowed to override any existing
938 * non-permanent entry. This means that when we remove this entry, the
939 * system automatically returns to the old behavior.
940 */
941 list_add_rcu(&p->list, last_perm);
942out:
943 spin_unlock_bh(&inetsw_lock);
944
945 synchronize_net();
946
947 return;
948
949out_permanent:
950 printk(KERN_ERR "Attempt to override permanent protocol %d.\n",
951 protocol);
952 goto out;
953
954out_illegal:
955 printk(KERN_ERR
956 "Ignoring attempt to register invalid socket type %d.\n",
957 p->type);
958 goto out;
959}
960
961void inet_unregister_protosw(struct inet_protosw *p)
962{
963 if (INET_PROTOSW_PERMANENT & p->flags) {
964 printk(KERN_ERR
965 "Attempt to unregister permanent protocol %d.\n",
966 p->protocol);
967 } else {
968 spin_lock_bh(&inetsw_lock);
969 list_del_rcu(&p->list);
970 spin_unlock_bh(&inetsw_lock);
971
972 synchronize_net();
973 }
974}
975
Arnaldo Carvalho de Melo32519f12005-08-09 19:50:02 -0700976/*
977 * Shall we try to damage output packets if routing dev changes?
978 */
979
980int sysctl_ip_dynaddr;
981
982static int inet_sk_reselect_saddr(struct sock *sk)
983{
984 struct inet_sock *inet = inet_sk(sk);
985 int err;
986 struct rtable *rt;
987 __u32 old_saddr = inet->saddr;
988 __u32 new_saddr;
989 __u32 daddr = inet->daddr;
990
991 if (inet->opt && inet->opt->srr)
992 daddr = inet->opt->faddr;
993
994 /* Query new route. */
995 err = ip_route_connect(&rt, daddr, 0,
996 RT_CONN_FLAGS(sk),
997 sk->sk_bound_dev_if,
998 sk->sk_protocol,
999 inet->sport, inet->dport, sk);
1000 if (err)
1001 return err;
1002
1003 sk_setup_caps(sk, &rt->u.dst);
1004
1005 new_saddr = rt->rt_src;
1006
1007 if (new_saddr == old_saddr)
1008 return 0;
1009
1010 if (sysctl_ip_dynaddr > 1) {
1011 printk(KERN_INFO "%s(): shifting inet->"
1012 "saddr from %d.%d.%d.%d to %d.%d.%d.%d\n",
1013 __FUNCTION__,
1014 NIPQUAD(old_saddr),
1015 NIPQUAD(new_saddr));
1016 }
1017
1018 inet->saddr = inet->rcv_saddr = new_saddr;
1019
1020 /*
1021 * XXX The only one ugly spot where we need to
1022 * XXX really change the sockets identity after
1023 * XXX it has entered the hashes. -DaveM
1024 *
1025 * Besides that, it does not check for connection
1026 * uniqueness. Wait for troubles.
1027 */
1028 __sk_prot_rehash(sk);
1029 return 0;
1030}
1031
1032int inet_sk_rebuild_header(struct sock *sk)
1033{
1034 struct inet_sock *inet = inet_sk(sk);
1035 struct rtable *rt = (struct rtable *)__sk_dst_check(sk, 0);
1036 u32 daddr;
1037 int err;
1038
1039 /* Route is OK, nothing to do. */
1040 if (rt)
1041 return 0;
1042
1043 /* Reroute. */
1044 daddr = inet->daddr;
1045 if (inet->opt && inet->opt->srr)
1046 daddr = inet->opt->faddr;
1047{
1048 struct flowi fl = {
1049 .oif = sk->sk_bound_dev_if,
1050 .nl_u = {
1051 .ip4_u = {
1052 .daddr = daddr,
1053 .saddr = inet->saddr,
1054 .tos = RT_CONN_FLAGS(sk),
1055 },
1056 },
1057 .proto = sk->sk_protocol,
1058 .uli_u = {
1059 .ports = {
1060 .sport = inet->sport,
1061 .dport = inet->dport,
1062 },
1063 },
1064 };
1065
1066 err = ip_route_output_flow(&rt, &fl, sk, 0);
1067}
1068 if (!err)
1069 sk_setup_caps(sk, &rt->u.dst);
1070 else {
1071 /* Routing failed... */
1072 sk->sk_route_caps = 0;
1073 /*
1074 * Other protocols have to map its equivalent state to TCP_SYN_SENT.
1075 * DCCP maps its DCCP_REQUESTING state to TCP_SYN_SENT. -acme
1076 */
1077 if (!sysctl_ip_dynaddr ||
1078 sk->sk_state != TCP_SYN_SENT ||
1079 (sk->sk_userlocks & SOCK_BINDADDR_LOCK) ||
1080 (err = inet_sk_reselect_saddr(sk)) != 0)
1081 sk->sk_err_soft = -err;
1082 }
1083
1084 return err;
1085}
1086
1087EXPORT_SYMBOL(inet_sk_rebuild_header);
1088
Linus Torvalds1da177e2005-04-16 15:20:36 -07001089#ifdef CONFIG_IP_MULTICAST
1090static struct net_protocol igmp_protocol = {
1091 .handler = igmp_rcv,
1092};
1093#endif
1094
1095static struct net_protocol tcp_protocol = {
1096 .handler = tcp_v4_rcv,
1097 .err_handler = tcp_v4_err,
1098 .no_policy = 1,
1099};
1100
1101static struct net_protocol udp_protocol = {
1102 .handler = udp_rcv,
1103 .err_handler = udp_err,
1104 .no_policy = 1,
1105};
1106
1107static struct net_protocol icmp_protocol = {
1108 .handler = icmp_rcv,
1109};
1110
1111static int __init init_ipv4_mibs(void)
1112{
1113 net_statistics[0] = alloc_percpu(struct linux_mib);
1114 net_statistics[1] = alloc_percpu(struct linux_mib);
1115 ip_statistics[0] = alloc_percpu(struct ipstats_mib);
1116 ip_statistics[1] = alloc_percpu(struct ipstats_mib);
1117 icmp_statistics[0] = alloc_percpu(struct icmp_mib);
1118 icmp_statistics[1] = alloc_percpu(struct icmp_mib);
1119 tcp_statistics[0] = alloc_percpu(struct tcp_mib);
1120 tcp_statistics[1] = alloc_percpu(struct tcp_mib);
1121 udp_statistics[0] = alloc_percpu(struct udp_mib);
1122 udp_statistics[1] = alloc_percpu(struct udp_mib);
1123 if (!
1124 (net_statistics[0] && net_statistics[1] && ip_statistics[0]
1125 && ip_statistics[1] && tcp_statistics[0] && tcp_statistics[1]
1126 && udp_statistics[0] && udp_statistics[1]))
1127 return -ENOMEM;
1128
1129 (void) tcp_mib_init();
1130
1131 return 0;
1132}
1133
1134static int ipv4_proc_init(void);
1135extern void ipfrag_init(void);
1136
Herbert Xu30e224d2005-07-05 14:40:10 -07001137/*
1138 * IP protocol layer initialiser
1139 */
1140
1141static struct packet_type ip_packet_type = {
1142 .type = __constant_htons(ETH_P_IP),
1143 .func = ip_rcv,
1144};
1145
Linus Torvalds1da177e2005-04-16 15:20:36 -07001146static int __init inet_init(void)
1147{
1148 struct sk_buff *dummy_skb;
1149 struct inet_protosw *q;
1150 struct list_head *r;
1151 int rc = -EINVAL;
1152
1153 if (sizeof(struct inet_skb_parm) > sizeof(dummy_skb->cb)) {
1154 printk(KERN_CRIT "%s: panic\n", __FUNCTION__);
1155 goto out;
1156 }
1157
1158 rc = proto_register(&tcp_prot, 1);
1159 if (rc)
1160 goto out;
1161
1162 rc = proto_register(&udp_prot, 1);
1163 if (rc)
1164 goto out_unregister_tcp_proto;
1165
1166 rc = proto_register(&raw_prot, 1);
1167 if (rc)
1168 goto out_unregister_udp_proto;
1169
1170 /*
1171 * Tell SOCKET that we are alive...
1172 */
1173
1174 (void)sock_register(&inet_family_ops);
1175
1176 /*
1177 * Add all the base protocols.
1178 */
1179
1180 if (inet_add_protocol(&icmp_protocol, IPPROTO_ICMP) < 0)
1181 printk(KERN_CRIT "inet_init: Cannot add ICMP protocol\n");
1182 if (inet_add_protocol(&udp_protocol, IPPROTO_UDP) < 0)
1183 printk(KERN_CRIT "inet_init: Cannot add UDP protocol\n");
1184 if (inet_add_protocol(&tcp_protocol, IPPROTO_TCP) < 0)
1185 printk(KERN_CRIT "inet_init: Cannot add TCP protocol\n");
1186#ifdef CONFIG_IP_MULTICAST
1187 if (inet_add_protocol(&igmp_protocol, IPPROTO_IGMP) < 0)
1188 printk(KERN_CRIT "inet_init: Cannot add IGMP protocol\n");
1189#endif
1190
1191 /* Register the socket-side information for inet_create. */
1192 for (r = &inetsw[0]; r < &inetsw[SOCK_MAX]; ++r)
1193 INIT_LIST_HEAD(r);
1194
1195 for (q = inetsw_array; q < &inetsw_array[INETSW_ARRAY_LEN]; ++q)
1196 inet_register_protosw(q);
1197
1198 /*
1199 * Set the ARP module up
1200 */
1201
1202 arp_init();
1203
1204 /*
1205 * Set the IP module up
1206 */
1207
1208 ip_init();
1209
1210 tcp_v4_init(&inet_family_ops);
1211
1212 /* Setup TCP slab cache for open requests. */
1213 tcp_init();
1214
1215
1216 /*
1217 * Set the ICMP layer up
1218 */
1219
1220 icmp_init(&inet_family_ops);
1221
1222 /*
1223 * Initialise the multicast router
1224 */
1225#if defined(CONFIG_IP_MROUTE)
1226 ip_mr_init();
1227#endif
1228 /*
1229 * Initialise per-cpu ipv4 mibs
1230 */
1231
1232 if(init_ipv4_mibs())
1233 printk(KERN_CRIT "inet_init: Cannot init ipv4 mibs\n"); ;
1234
1235 ipv4_proc_init();
1236
1237 ipfrag_init();
1238
Herbert Xu30e224d2005-07-05 14:40:10 -07001239 dev_add_pack(&ip_packet_type);
1240
Linus Torvalds1da177e2005-04-16 15:20:36 -07001241 rc = 0;
1242out:
1243 return rc;
1244out_unregister_tcp_proto:
1245 proto_unregister(&tcp_prot);
1246out_unregister_udp_proto:
1247 proto_unregister(&udp_prot);
1248 goto out;
1249}
1250
1251module_init(inet_init);
1252
1253/* ------------------------------------------------------------------------ */
1254
1255#ifdef CONFIG_PROC_FS
1256extern int fib_proc_init(void);
1257extern void fib_proc_exit(void);
Robert Olsson19baf832005-06-21 12:43:18 -07001258#ifdef CONFIG_IP_FIB_TRIE
1259extern int fib_stat_proc_init(void);
1260extern void fib_stat_proc_exit(void);
1261#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07001262extern int ip_misc_proc_init(void);
1263extern int raw_proc_init(void);
1264extern void raw_proc_exit(void);
1265extern int tcp4_proc_init(void);
1266extern void tcp4_proc_exit(void);
1267extern int udp4_proc_init(void);
1268extern void udp4_proc_exit(void);
1269
1270static int __init ipv4_proc_init(void)
1271{
1272 int rc = 0;
1273
1274 if (raw_proc_init())
1275 goto out_raw;
1276 if (tcp4_proc_init())
1277 goto out_tcp;
1278 if (udp4_proc_init())
1279 goto out_udp;
1280 if (fib_proc_init())
1281 goto out_fib;
Robert Olsson19baf832005-06-21 12:43:18 -07001282#ifdef CONFIG_IP_FIB_TRIE
1283 if (fib_stat_proc_init())
1284 goto out_fib_stat;
Stephen Hemmingerc877efb2005-07-19 14:01:51 -07001285#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07001286 if (ip_misc_proc_init())
1287 goto out_misc;
1288out:
1289 return rc;
1290out_misc:
Robert Olsson19baf832005-06-21 12:43:18 -07001291#ifdef CONFIG_IP_FIB_TRIE
1292 fib_stat_proc_exit();
1293out_fib_stat:
1294#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07001295 fib_proc_exit();
1296out_fib:
1297 udp4_proc_exit();
1298out_udp:
1299 tcp4_proc_exit();
1300out_tcp:
1301 raw_proc_exit();
1302out_raw:
1303 rc = -ENOMEM;
1304 goto out;
1305}
1306
1307#else /* CONFIG_PROC_FS */
1308static int __init ipv4_proc_init(void)
1309{
1310 return 0;
1311}
1312#endif /* CONFIG_PROC_FS */
1313
1314MODULE_ALIAS_NETPROTO(PF_INET);
1315
1316EXPORT_SYMBOL(inet_accept);
1317EXPORT_SYMBOL(inet_bind);
1318EXPORT_SYMBOL(inet_dgram_connect);
1319EXPORT_SYMBOL(inet_dgram_ops);
1320EXPORT_SYMBOL(inet_getname);
1321EXPORT_SYMBOL(inet_ioctl);
1322EXPORT_SYMBOL(inet_listen);
1323EXPORT_SYMBOL(inet_register_protosw);
1324EXPORT_SYMBOL(inet_release);
1325EXPORT_SYMBOL(inet_sendmsg);
1326EXPORT_SYMBOL(inet_shutdown);
1327EXPORT_SYMBOL(inet_sock_destruct);
1328EXPORT_SYMBOL(inet_stream_connect);
1329EXPORT_SYMBOL(inet_stream_ops);
1330EXPORT_SYMBOL(inet_unregister_protosw);
1331EXPORT_SYMBOL(net_statistics);
Neil Hormancdac4e02005-06-13 15:12:33 -07001332EXPORT_SYMBOL(sysctl_ip_nonlocal_bind);