xref: /linux/net/ipv4/af_inet.c (revision eb2bce7f5e7ac1ca6da434461217fadf3c688d2c)
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  * Version:	$Id: af_inet.c,v 1.137 2002/02/01 22:01:03 davem Exp $
9  *
10  * Authors:	Ross Biro
11  *		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/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 
92 #include <asm/uaccess.h>
93 #include <asm/system.h>
94 
95 #include <linux/smp_lock.h>
96 #include <linux/inet.h>
97 #include <linux/igmp.h>
98 #include <linux/inetdevice.h>
99 #include <linux/netdevice.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 <linux/skbuff.h>
110 #include <net/sock.h>
111 #include <net/raw.h>
112 #include <net/icmp.h>
113 #include <net/ipip.h>
114 #include <net/inet_common.h>
115 #include <net/xfrm.h>
116 #ifdef CONFIG_IP_MROUTE
117 #include <linux/mroute.h>
118 #endif
119 
120 DEFINE_SNMP_STAT(struct linux_mib, net_statistics) __read_mostly;
121 
122 extern void ip_mc_drop_socket(struct sock *sk);
123 
124 /* The inetsw table contains everything that inet_create needs to
125  * build a new socket.
126  */
127 static struct list_head inetsw[SOCK_MAX];
128 static DEFINE_SPINLOCK(inetsw_lock);
129 
130 /* New destruction routine */
131 
132 void inet_sock_destruct(struct sock *sk)
133 {
134 	struct inet_sock *inet = inet_sk(sk);
135 
136 	__skb_queue_purge(&sk->sk_receive_queue);
137 	__skb_queue_purge(&sk->sk_error_queue);
138 
139 	if (sk->sk_type == SOCK_STREAM && sk->sk_state != TCP_CLOSE) {
140 		printk("Attempt to release TCP socket in state %d %p\n",
141 		       sk->sk_state, sk);
142 		return;
143 	}
144 	if (!sock_flag(sk, SOCK_DEAD)) {
145 		printk("Attempt to release alive inet socket %p\n", sk);
146 		return;
147 	}
148 
149 	BUG_TRAP(!atomic_read(&sk->sk_rmem_alloc));
150 	BUG_TRAP(!atomic_read(&sk->sk_wmem_alloc));
151 	BUG_TRAP(!sk->sk_wmem_queued);
152 	BUG_TRAP(!sk->sk_forward_alloc);
153 
154 	kfree(inet->opt);
155 	dst_release(sk->sk_dst_cache);
156 	sk_refcnt_debug_dec(sk);
157 }
158 
159 /*
160  *	The routines beyond this point handle the behaviour of an AF_INET
161  *	socket object. Mostly it punts to the subprotocols of IP to do
162  *	the work.
163  */
164 
165 /*
166  *	Automatically bind an unbound socket.
167  */
168 
169 static int inet_autobind(struct sock *sk)
170 {
171 	struct inet_sock *inet;
172 	/* We may need to bind the socket. */
173 	lock_sock(sk);
174 	inet = inet_sk(sk);
175 	if (!inet->num) {
176 		if (sk->sk_prot->get_port(sk, 0)) {
177 			release_sock(sk);
178 			return -EAGAIN;
179 		}
180 		inet->sport = htons(inet->num);
181 	}
182 	release_sock(sk);
183 	return 0;
184 }
185 
186 /*
187  *	Move a socket into listening state.
188  */
189 int inet_listen(struct socket *sock, int backlog)
190 {
191 	struct sock *sk = sock->sk;
192 	unsigned char old_state;
193 	int err;
194 
195 	lock_sock(sk);
196 
197 	err = -EINVAL;
198 	if (sock->state != SS_UNCONNECTED || sock->type != SOCK_STREAM)
199 		goto out;
200 
201 	old_state = sk->sk_state;
202 	if (!((1 << old_state) & (TCPF_CLOSE | TCPF_LISTEN)))
203 		goto out;
204 
205 	/* Really, if the socket is already in listen state
206 	 * we can only allow the backlog to be adjusted.
207 	 */
208 	if (old_state != TCP_LISTEN) {
209 		err = inet_csk_listen_start(sk, backlog);
210 		if (err)
211 			goto out;
212 	}
213 	sk->sk_max_ack_backlog = backlog;
214 	err = 0;
215 
216 out:
217 	release_sock(sk);
218 	return err;
219 }
220 
221 u32 inet_ehash_secret __read_mostly;
222 EXPORT_SYMBOL(inet_ehash_secret);
223 
224 /*
225  * inet_ehash_secret must be set exactly once
226  * Instead of using a dedicated spinlock, we (ab)use inetsw_lock
227  */
228 void build_ehash_secret(void)
229 {
230 	u32 rnd;
231 	do {
232 		get_random_bytes(&rnd, sizeof(rnd));
233 	} while (rnd == 0);
234 	spin_lock_bh(&inetsw_lock);
235 	if (!inet_ehash_secret)
236 		inet_ehash_secret = rnd;
237 	spin_unlock_bh(&inetsw_lock);
238 }
239 EXPORT_SYMBOL(build_ehash_secret);
240 
241 /*
242  *	Create an inet socket.
243  */
244 
245 static int inet_create(struct socket *sock, int protocol)
246 {
247 	struct sock *sk;
248 	struct list_head *p;
249 	struct inet_protosw *answer;
250 	struct inet_sock *inet;
251 	struct proto *answer_prot;
252 	unsigned char answer_flags;
253 	char answer_no_check;
254 	int try_loading_module = 0;
255 	int err;
256 
257 	if (sock->type != SOCK_RAW &&
258 	    sock->type != SOCK_DGRAM &&
259 	    !inet_ehash_secret)
260 		build_ehash_secret();
261 
262 	sock->state = SS_UNCONNECTED;
263 
264 	/* Look for the requested type/protocol pair. */
265 	answer = NULL;
266 lookup_protocol:
267 	err = -ESOCKTNOSUPPORT;
268 	rcu_read_lock();
269 	list_for_each_rcu(p, &inetsw[sock->type]) {
270 		answer = list_entry(p, struct inet_protosw, list);
271 
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 		answer = NULL;
287 	}
288 
289 	if (unlikely(answer == NULL)) {
290 		if (try_loading_module < 2) {
291 			rcu_read_unlock();
292 			/*
293 			 * Be more specific, e.g. net-pf-2-proto-132-type-1
294 			 * (net-pf-PF_INET-proto-IPPROTO_SCTP-type-SOCK_STREAM)
295 			 */
296 			if (++try_loading_module == 1)
297 				request_module("net-pf-%d-proto-%d-type-%d",
298 					       PF_INET, protocol, sock->type);
299 			/*
300 			 * Fall back to generic, e.g. net-pf-2-proto-132
301 			 * (net-pf-PF_INET-proto-IPPROTO_SCTP)
302 			 */
303 			else
304 				request_module("net-pf-%d-proto-%d",
305 					       PF_INET, protocol);
306 			goto lookup_protocol;
307 		} else
308 			goto out_rcu_unlock;
309 	}
310 
311 	err = -EPERM;
312 	if (answer->capability > 0 && !capable(answer->capability))
313 		goto out_rcu_unlock;
314 
315 	sock->ops = answer->ops;
316 	answer_prot = answer->prot;
317 	answer_no_check = answer->no_check;
318 	answer_flags = answer->flags;
319 	rcu_read_unlock();
320 
321 	BUG_TRAP(answer_prot->slab != NULL);
322 
323 	err = -ENOBUFS;
324 	sk = sk_alloc(PF_INET, GFP_KERNEL, answer_prot, 1);
325 	if (sk == NULL)
326 		goto out;
327 
328 	err = 0;
329 	sk->sk_no_check = answer_no_check;
330 	if (INET_PROTOSW_REUSE & answer_flags)
331 		sk->sk_reuse = 1;
332 
333 	inet = inet_sk(sk);
334 	inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
335 
336 	if (SOCK_RAW == sock->type) {
337 		inet->num = protocol;
338 		if (IPPROTO_RAW == protocol)
339 			inet->hdrincl = 1;
340 	}
341 
342 	if (ipv4_config.no_pmtu_disc)
343 		inet->pmtudisc = IP_PMTUDISC_DONT;
344 	else
345 		inet->pmtudisc = IP_PMTUDISC_WANT;
346 
347 	inet->id = 0;
348 
349 	sock_init_data(sock, sk);
350 
351 	sk->sk_destruct	   = inet_sock_destruct;
352 	sk->sk_family	   = PF_INET;
353 	sk->sk_protocol	   = protocol;
354 	sk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
355 
356 	inet->uc_ttl	= -1;
357 	inet->mc_loop	= 1;
358 	inet->mc_ttl	= 1;
359 	inet->mc_index	= 0;
360 	inet->mc_list	= NULL;
361 
362 	sk_refcnt_debug_inc(sk);
363 
364 	if (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->sport = htons(inet->num);
371 		/* Add to protocol hash chains. */
372 		sk->sk_prot->hash(sk);
373 	}
374 
375 	if (sk->sk_prot->init) {
376 		err = sk->sk_prot->init(sk);
377 		if (err)
378 			sk_common_release(sk);
379 	}
380 out:
381 	return err;
382 out_rcu_unlock:
383 	rcu_read_unlock();
384 	goto out;
385 }
386 
387 
388 /*
389  *	The peer socket should always be NULL (or else). When we call this
390  *	function we are destroying the object and from then on nobody
391  *	should refer to it.
392  */
393 int inet_release(struct socket *sock)
394 {
395 	struct sock *sk = sock->sk;
396 
397 	if (sk) {
398 		long timeout;
399 
400 		/* Applications forget to leave groups before exiting */
401 		ip_mc_drop_socket(sk);
402 
403 		/* If linger is set, we don't return until the close
404 		 * is complete.  Otherwise we return immediately. The
405 		 * actually closing is done the same either way.
406 		 *
407 		 * If the close is due to the process exiting, we never
408 		 * linger..
409 		 */
410 		timeout = 0;
411 		if (sock_flag(sk, SOCK_LINGER) &&
412 		    !(current->flags & PF_EXITING))
413 			timeout = sk->sk_lingertime;
414 		sock->sk = NULL;
415 		sk->sk_prot->close(sk, timeout);
416 	}
417 	return 0;
418 }
419 
420 /* It is off by default, see below. */
421 int sysctl_ip_nonlocal_bind __read_mostly;
422 
423 int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
424 {
425 	struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
426 	struct sock *sk = sock->sk;
427 	struct inet_sock *inet = inet_sk(sk);
428 	unsigned short snum;
429 	int chk_addr_ret;
430 	int err;
431 
432 	/* If the socket has its own bind function then use it. (RAW) */
433 	if (sk->sk_prot->bind) {
434 		err = sk->sk_prot->bind(sk, uaddr, addr_len);
435 		goto out;
436 	}
437 	err = -EINVAL;
438 	if (addr_len < sizeof(struct sockaddr_in))
439 		goto out;
440 
441 	chk_addr_ret = inet_addr_type(addr->sin_addr.s_addr);
442 
443 	/* Not specified by any standard per-se, however it breaks too
444 	 * many applications when removed.  It is unfortunate since
445 	 * allowing applications to make a non-local bind solves
446 	 * several problems with systems using dynamic addressing.
447 	 * (ie. your servers still start up even if your ISDN link
448 	 *  is temporarily down)
449 	 */
450 	err = -EADDRNOTAVAIL;
451 	if (!sysctl_ip_nonlocal_bind &&
452 	    !inet->freebind &&
453 	    addr->sin_addr.s_addr != INADDR_ANY &&
454 	    chk_addr_ret != RTN_LOCAL &&
455 	    chk_addr_ret != RTN_MULTICAST &&
456 	    chk_addr_ret != RTN_BROADCAST)
457 		goto out;
458 
459 	snum = ntohs(addr->sin_port);
460 	err = -EACCES;
461 	if (snum && snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
462 		goto out;
463 
464 	/*      We keep a pair of addresses. rcv_saddr is the one
465 	 *      used by hash lookups, and saddr is used for transmit.
466 	 *
467 	 *      In the BSD API these are the same except where it
468 	 *      would be illegal to use them (multicast/broadcast) in
469 	 *      which case the sending device address is used.
470 	 */
471 	lock_sock(sk);
472 
473 	/* Check these errors (active socket, double bind). */
474 	err = -EINVAL;
475 	if (sk->sk_state != TCP_CLOSE || inet->num)
476 		goto out_release_sock;
477 
478 	inet->rcv_saddr = inet->saddr = addr->sin_addr.s_addr;
479 	if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST)
480 		inet->saddr = 0;  /* Use device */
481 
482 	/* Make sure we are allowed to bind here. */
483 	if (sk->sk_prot->get_port(sk, snum)) {
484 		inet->saddr = inet->rcv_saddr = 0;
485 		err = -EADDRINUSE;
486 		goto out_release_sock;
487 	}
488 
489 	if (inet->rcv_saddr)
490 		sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
491 	if (snum)
492 		sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
493 	inet->sport = htons(inet->num);
494 	inet->daddr = 0;
495 	inet->dport = 0;
496 	sk_dst_reset(sk);
497 	err = 0;
498 out_release_sock:
499 	release_sock(sk);
500 out:
501 	return err;
502 }
503 
504 int inet_dgram_connect(struct socket *sock, struct sockaddr * uaddr,
505 		       int addr_len, int flags)
506 {
507 	struct sock *sk = sock->sk;
508 
509 	if (uaddr->sa_family == AF_UNSPEC)
510 		return sk->sk_prot->disconnect(sk, flags);
511 
512 	if (!inet_sk(sk)->num && inet_autobind(sk))
513 		return -EAGAIN;
514 	return sk->sk_prot->connect(sk, (struct sockaddr *)uaddr, addr_len);
515 }
516 
517 static long inet_wait_for_connect(struct sock *sk, long timeo)
518 {
519 	DEFINE_WAIT(wait);
520 
521 	prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
522 
523 	/* Basic assumption: if someone sets sk->sk_err, he _must_
524 	 * change state of the socket from TCP_SYN_*.
525 	 * Connect() does not allow to get error notifications
526 	 * without closing the socket.
527 	 */
528 	while ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
529 		release_sock(sk);
530 		timeo = schedule_timeout(timeo);
531 		lock_sock(sk);
532 		if (signal_pending(current) || !timeo)
533 			break;
534 		prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
535 	}
536 	finish_wait(sk->sk_sleep, &wait);
537 	return timeo;
538 }
539 
540 /*
541  *	Connect to a remote host. There is regrettably still a little
542  *	TCP 'magic' in here.
543  */
544 int inet_stream_connect(struct socket *sock, struct sockaddr *uaddr,
545 			int addr_len, int flags)
546 {
547 	struct sock *sk = sock->sk;
548 	int err;
549 	long timeo;
550 
551 	lock_sock(sk);
552 
553 	if (uaddr->sa_family == AF_UNSPEC) {
554 		err = sk->sk_prot->disconnect(sk, flags);
555 		sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
556 		goto out;
557 	}
558 
559 	switch (sock->state) {
560 	default:
561 		err = -EINVAL;
562 		goto out;
563 	case SS_CONNECTED:
564 		err = -EISCONN;
565 		goto out;
566 	case SS_CONNECTING:
567 		err = -EALREADY;
568 		/* Fall out of switch with err, set for this state */
569 		break;
570 	case SS_UNCONNECTED:
571 		err = -EISCONN;
572 		if (sk->sk_state != TCP_CLOSE)
573 			goto out;
574 
575 		err = sk->sk_prot->connect(sk, uaddr, addr_len);
576 		if (err < 0)
577 			goto out;
578 
579 		sock->state = SS_CONNECTING;
580 
581 		/* Just entered SS_CONNECTING state; the only
582 		 * difference is that return value in non-blocking
583 		 * case is EINPROGRESS, rather than EALREADY.
584 		 */
585 		err = -EINPROGRESS;
586 		break;
587 	}
588 
589 	timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
590 
591 	if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
592 		/* Error code is set above */
593 		if (!timeo || !inet_wait_for_connect(sk, timeo))
594 			goto out;
595 
596 		err = sock_intr_errno(timeo);
597 		if (signal_pending(current))
598 			goto out;
599 	}
600 
601 	/* Connection was closed by RST, timeout, ICMP error
602 	 * or another process disconnected us.
603 	 */
604 	if (sk->sk_state == TCP_CLOSE)
605 		goto sock_error;
606 
607 	/* sk->sk_err may be not zero now, if RECVERR was ordered by user
608 	 * and error was received after socket entered established state.
609 	 * Hence, it is handled normally after connect() return successfully.
610 	 */
611 
612 	sock->state = SS_CONNECTED;
613 	err = 0;
614 out:
615 	release_sock(sk);
616 	return err;
617 
618 sock_error:
619 	err = sock_error(sk) ? : -ECONNABORTED;
620 	sock->state = SS_UNCONNECTED;
621 	if (sk->sk_prot->disconnect(sk, flags))
622 		sock->state = SS_DISCONNECTING;
623 	goto out;
624 }
625 
626 /*
627  *	Accept a pending connection. The TCP layer now gives BSD semantics.
628  */
629 
630 int inet_accept(struct socket *sock, struct socket *newsock, int flags)
631 {
632 	struct sock *sk1 = sock->sk;
633 	int err = -EINVAL;
634 	struct sock *sk2 = sk1->sk_prot->accept(sk1, flags, &err);
635 
636 	if (!sk2)
637 		goto do_err;
638 
639 	lock_sock(sk2);
640 
641 	BUG_TRAP((1 << sk2->sk_state) &
642 		 (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT | TCPF_CLOSE));
643 
644 	sock_graft(sk2, newsock);
645 
646 	newsock->state = SS_CONNECTED;
647 	err = 0;
648 	release_sock(sk2);
649 do_err:
650 	return err;
651 }
652 
653 
654 /*
655  *	This does both peername and sockname.
656  */
657 int inet_getname(struct socket *sock, struct sockaddr *uaddr,
658 			int *uaddr_len, int peer)
659 {
660 	struct sock *sk		= sock->sk;
661 	struct inet_sock *inet	= inet_sk(sk);
662 	struct sockaddr_in *sin	= (struct sockaddr_in *)uaddr;
663 
664 	sin->sin_family = AF_INET;
665 	if (peer) {
666 		if (!inet->dport ||
667 		    (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
668 		     peer == 1))
669 			return -ENOTCONN;
670 		sin->sin_port = inet->dport;
671 		sin->sin_addr.s_addr = inet->daddr;
672 	} else {
673 		__be32 addr = inet->rcv_saddr;
674 		if (!addr)
675 			addr = inet->saddr;
676 		sin->sin_port = inet->sport;
677 		sin->sin_addr.s_addr = addr;
678 	}
679 	memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
680 	*uaddr_len = sizeof(*sin);
681 	return 0;
682 }
683 
684 int inet_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
685 		 size_t size)
686 {
687 	struct sock *sk = sock->sk;
688 
689 	/* We may need to bind the socket. */
690 	if (!inet_sk(sk)->num && inet_autobind(sk))
691 		return -EAGAIN;
692 
693 	return sk->sk_prot->sendmsg(iocb, sk, msg, size);
694 }
695 
696 
697 static ssize_t inet_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
698 {
699 	struct sock *sk = sock->sk;
700 
701 	/* We may need to bind the socket. */
702 	if (!inet_sk(sk)->num && inet_autobind(sk))
703 		return -EAGAIN;
704 
705 	if (sk->sk_prot->sendpage)
706 		return sk->sk_prot->sendpage(sk, page, offset, size, flags);
707 	return sock_no_sendpage(sock, page, offset, size, flags);
708 }
709 
710 
711 int inet_shutdown(struct socket *sock, int how)
712 {
713 	struct sock *sk = sock->sk;
714 	int err = 0;
715 
716 	/* This should really check to make sure
717 	 * the socket is a TCP socket. (WHY AC...)
718 	 */
719 	how++; /* maps 0->1 has the advantage of making bit 1 rcvs and
720 		       1->2 bit 2 snds.
721 		       2->3 */
722 	if ((how & ~SHUTDOWN_MASK) || !how)	/* MAXINT->0 */
723 		return -EINVAL;
724 
725 	lock_sock(sk);
726 	if (sock->state == SS_CONNECTING) {
727 		if ((1 << sk->sk_state) &
728 		    (TCPF_SYN_SENT | TCPF_SYN_RECV | TCPF_CLOSE))
729 			sock->state = SS_DISCONNECTING;
730 		else
731 			sock->state = SS_CONNECTED;
732 	}
733 
734 	switch (sk->sk_state) {
735 	case TCP_CLOSE:
736 		err = -ENOTCONN;
737 		/* Hack to wake up other listeners, who can poll for
738 		   POLLHUP, even on eg. unconnected UDP sockets -- RR */
739 	default:
740 		sk->sk_shutdown |= how;
741 		if (sk->sk_prot->shutdown)
742 			sk->sk_prot->shutdown(sk, how);
743 		break;
744 
745 	/* Remaining two branches are temporary solution for missing
746 	 * close() in multithreaded environment. It is _not_ a good idea,
747 	 * but we have no choice until close() is repaired at VFS level.
748 	 */
749 	case TCP_LISTEN:
750 		if (!(how & RCV_SHUTDOWN))
751 			break;
752 		/* Fall through */
753 	case TCP_SYN_SENT:
754 		err = sk->sk_prot->disconnect(sk, O_NONBLOCK);
755 		sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
756 		break;
757 	}
758 
759 	/* Wake up anyone sleeping in poll. */
760 	sk->sk_state_change(sk);
761 	release_sock(sk);
762 	return err;
763 }
764 
765 /*
766  *	ioctl() calls you can issue on an INET socket. Most of these are
767  *	device configuration and stuff and very rarely used. Some ioctls
768  *	pass on to the socket itself.
769  *
770  *	NOTE: I like the idea of a module for the config stuff. ie ifconfig
771  *	loads the devconfigure module does its configuring and unloads it.
772  *	There's a good 20K of config code hanging around the kernel.
773  */
774 
775 int inet_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
776 {
777 	struct sock *sk = sock->sk;
778 	int err = 0;
779 
780 	switch (cmd) {
781 		case SIOCGSTAMP:
782 			err = sock_get_timestamp(sk, (struct timeval __user *)arg);
783 			break;
784 		case SIOCGSTAMPNS:
785 			err = sock_get_timestampns(sk, (struct timespec __user *)arg);
786 			break;
787 		case SIOCADDRT:
788 		case SIOCDELRT:
789 		case SIOCRTMSG:
790 			err = ip_rt_ioctl(cmd, (void __user *)arg);
791 			break;
792 		case SIOCDARP:
793 		case SIOCGARP:
794 		case SIOCSARP:
795 			err = arp_ioctl(cmd, (void __user *)arg);
796 			break;
797 		case SIOCGIFADDR:
798 		case SIOCSIFADDR:
799 		case SIOCGIFBRDADDR:
800 		case SIOCSIFBRDADDR:
801 		case SIOCGIFNETMASK:
802 		case SIOCSIFNETMASK:
803 		case SIOCGIFDSTADDR:
804 		case SIOCSIFDSTADDR:
805 		case SIOCSIFPFLAGS:
806 		case SIOCGIFPFLAGS:
807 		case SIOCSIFFLAGS:
808 			err = devinet_ioctl(cmd, (void __user *)arg);
809 			break;
810 		default:
811 			if (sk->sk_prot->ioctl)
812 				err = sk->sk_prot->ioctl(sk, cmd, arg);
813 			else
814 				err = -ENOIOCTLCMD;
815 			break;
816 	}
817 	return err;
818 }
819 
820 const struct proto_ops inet_stream_ops = {
821 	.family		   = PF_INET,
822 	.owner		   = THIS_MODULE,
823 	.release	   = inet_release,
824 	.bind		   = inet_bind,
825 	.connect	   = inet_stream_connect,
826 	.socketpair	   = sock_no_socketpair,
827 	.accept		   = inet_accept,
828 	.getname	   = inet_getname,
829 	.poll		   = tcp_poll,
830 	.ioctl		   = inet_ioctl,
831 	.listen		   = inet_listen,
832 	.shutdown	   = inet_shutdown,
833 	.setsockopt	   = sock_common_setsockopt,
834 	.getsockopt	   = sock_common_getsockopt,
835 	.sendmsg	   = inet_sendmsg,
836 	.recvmsg	   = sock_common_recvmsg,
837 	.mmap		   = sock_no_mmap,
838 	.sendpage	   = tcp_sendpage,
839 #ifdef CONFIG_COMPAT
840 	.compat_setsockopt = compat_sock_common_setsockopt,
841 	.compat_getsockopt = compat_sock_common_getsockopt,
842 #endif
843 };
844 
845 const struct proto_ops inet_dgram_ops = {
846 	.family		   = PF_INET,
847 	.owner		   = THIS_MODULE,
848 	.release	   = inet_release,
849 	.bind		   = inet_bind,
850 	.connect	   = inet_dgram_connect,
851 	.socketpair	   = sock_no_socketpair,
852 	.accept		   = sock_no_accept,
853 	.getname	   = inet_getname,
854 	.poll		   = udp_poll,
855 	.ioctl		   = inet_ioctl,
856 	.listen		   = sock_no_listen,
857 	.shutdown	   = inet_shutdown,
858 	.setsockopt	   = sock_common_setsockopt,
859 	.getsockopt	   = sock_common_getsockopt,
860 	.sendmsg	   = inet_sendmsg,
861 	.recvmsg	   = sock_common_recvmsg,
862 	.mmap		   = sock_no_mmap,
863 	.sendpage	   = inet_sendpage,
864 #ifdef CONFIG_COMPAT
865 	.compat_setsockopt = compat_sock_common_setsockopt,
866 	.compat_getsockopt = compat_sock_common_getsockopt,
867 #endif
868 };
869 
870 /*
871  * For SOCK_RAW sockets; should be the same as inet_dgram_ops but without
872  * udp_poll
873  */
874 static const struct proto_ops inet_sockraw_ops = {
875 	.family		   = PF_INET,
876 	.owner		   = THIS_MODULE,
877 	.release	   = inet_release,
878 	.bind		   = inet_bind,
879 	.connect	   = inet_dgram_connect,
880 	.socketpair	   = sock_no_socketpair,
881 	.accept		   = sock_no_accept,
882 	.getname	   = inet_getname,
883 	.poll		   = datagram_poll,
884 	.ioctl		   = inet_ioctl,
885 	.listen		   = sock_no_listen,
886 	.shutdown	   = inet_shutdown,
887 	.setsockopt	   = sock_common_setsockopt,
888 	.getsockopt	   = sock_common_getsockopt,
889 	.sendmsg	   = inet_sendmsg,
890 	.recvmsg	   = sock_common_recvmsg,
891 	.mmap		   = sock_no_mmap,
892 	.sendpage	   = inet_sendpage,
893 #ifdef CONFIG_COMPAT
894 	.compat_setsockopt = compat_sock_common_setsockopt,
895 	.compat_getsockopt = compat_sock_common_getsockopt,
896 #endif
897 };
898 
899 static struct net_proto_family inet_family_ops = {
900 	.family = PF_INET,
901 	.create = inet_create,
902 	.owner	= THIS_MODULE,
903 };
904 
905 /* Upon startup we insert all the elements in inetsw_array[] into
906  * the linked list inetsw.
907  */
908 static struct inet_protosw inetsw_array[] =
909 {
910 	{
911 		.type =       SOCK_STREAM,
912 		.protocol =   IPPROTO_TCP,
913 		.prot =       &tcp_prot,
914 		.ops =        &inet_stream_ops,
915 		.capability = -1,
916 		.no_check =   0,
917 		.flags =      INET_PROTOSW_PERMANENT |
918 			      INET_PROTOSW_ICSK,
919 	},
920 
921 	{
922 		.type =       SOCK_DGRAM,
923 		.protocol =   IPPROTO_UDP,
924 		.prot =       &udp_prot,
925 		.ops =        &inet_dgram_ops,
926 		.capability = -1,
927 		.no_check =   UDP_CSUM_DEFAULT,
928 		.flags =      INET_PROTOSW_PERMANENT,
929        },
930 
931 
932        {
933 	       .type =       SOCK_RAW,
934 	       .protocol =   IPPROTO_IP,	/* wild card */
935 	       .prot =       &raw_prot,
936 	       .ops =        &inet_sockraw_ops,
937 	       .capability = CAP_NET_RAW,
938 	       .no_check =   UDP_CSUM_DEFAULT,
939 	       .flags =      INET_PROTOSW_REUSE,
940        }
941 };
942 
943 #define INETSW_ARRAY_LEN (sizeof(inetsw_array) / sizeof(struct inet_protosw))
944 
945 void inet_register_protosw(struct inet_protosw *p)
946 {
947 	struct list_head *lh;
948 	struct inet_protosw *answer;
949 	int protocol = p->protocol;
950 	struct list_head *last_perm;
951 
952 	spin_lock_bh(&inetsw_lock);
953 
954 	if (p->type >= SOCK_MAX)
955 		goto out_illegal;
956 
957 	/* If we are trying to override a permanent protocol, bail. */
958 	answer = NULL;
959 	last_perm = &inetsw[p->type];
960 	list_for_each(lh, &inetsw[p->type]) {
961 		answer = list_entry(lh, struct inet_protosw, list);
962 
963 		/* Check only the non-wild match. */
964 		if (INET_PROTOSW_PERMANENT & answer->flags) {
965 			if (protocol == answer->protocol)
966 				break;
967 			last_perm = lh;
968 		}
969 
970 		answer = NULL;
971 	}
972 	if (answer)
973 		goto out_permanent;
974 
975 	/* Add the new entry after the last permanent entry if any, so that
976 	 * the new entry does not override a permanent entry when matched with
977 	 * a wild-card protocol. But it is allowed to override any existing
978 	 * non-permanent entry.  This means that when we remove this entry, the
979 	 * system automatically returns to the old behavior.
980 	 */
981 	list_add_rcu(&p->list, last_perm);
982 out:
983 	spin_unlock_bh(&inetsw_lock);
984 
985 	synchronize_net();
986 
987 	return;
988 
989 out_permanent:
990 	printk(KERN_ERR "Attempt to override permanent protocol %d.\n",
991 	       protocol);
992 	goto out;
993 
994 out_illegal:
995 	printk(KERN_ERR
996 	       "Ignoring attempt to register invalid socket type %d.\n",
997 	       p->type);
998 	goto out;
999 }
1000 
1001 void inet_unregister_protosw(struct inet_protosw *p)
1002 {
1003 	if (INET_PROTOSW_PERMANENT & p->flags) {
1004 		printk(KERN_ERR
1005 		       "Attempt to unregister permanent protocol %d.\n",
1006 		       p->protocol);
1007 	} else {
1008 		spin_lock_bh(&inetsw_lock);
1009 		list_del_rcu(&p->list);
1010 		spin_unlock_bh(&inetsw_lock);
1011 
1012 		synchronize_net();
1013 	}
1014 }
1015 
1016 /*
1017  *      Shall we try to damage output packets if routing dev changes?
1018  */
1019 
1020 int sysctl_ip_dynaddr __read_mostly;
1021 
1022 static int inet_sk_reselect_saddr(struct sock *sk)
1023 {
1024 	struct inet_sock *inet = inet_sk(sk);
1025 	int err;
1026 	struct rtable *rt;
1027 	__be32 old_saddr = inet->saddr;
1028 	__be32 new_saddr;
1029 	__be32 daddr = inet->daddr;
1030 
1031 	if (inet->opt && inet->opt->srr)
1032 		daddr = inet->opt->faddr;
1033 
1034 	/* Query new route. */
1035 	err = ip_route_connect(&rt, daddr, 0,
1036 			       RT_CONN_FLAGS(sk),
1037 			       sk->sk_bound_dev_if,
1038 			       sk->sk_protocol,
1039 			       inet->sport, inet->dport, sk, 0);
1040 	if (err)
1041 		return err;
1042 
1043 	sk_setup_caps(sk, &rt->u.dst);
1044 
1045 	new_saddr = rt->rt_src;
1046 
1047 	if (new_saddr == old_saddr)
1048 		return 0;
1049 
1050 	if (sysctl_ip_dynaddr > 1) {
1051 		printk(KERN_INFO "%s(): shifting inet->"
1052 				 "saddr from %d.%d.%d.%d to %d.%d.%d.%d\n",
1053 		       __FUNCTION__,
1054 		       NIPQUAD(old_saddr),
1055 		       NIPQUAD(new_saddr));
1056 	}
1057 
1058 	inet->saddr = inet->rcv_saddr = new_saddr;
1059 
1060 	/*
1061 	 * XXX The only one ugly spot where we need to
1062 	 * XXX really change the sockets identity after
1063 	 * XXX it has entered the hashes. -DaveM
1064 	 *
1065 	 * Besides that, it does not check for connection
1066 	 * uniqueness. Wait for troubles.
1067 	 */
1068 	__sk_prot_rehash(sk);
1069 	return 0;
1070 }
1071 
1072 int inet_sk_rebuild_header(struct sock *sk)
1073 {
1074 	struct inet_sock *inet = inet_sk(sk);
1075 	struct rtable *rt = (struct rtable *)__sk_dst_check(sk, 0);
1076 	__be32 daddr;
1077 	int err;
1078 
1079 	/* Route is OK, nothing to do. */
1080 	if (rt)
1081 		return 0;
1082 
1083 	/* Reroute. */
1084 	daddr = inet->daddr;
1085 	if (inet->opt && inet->opt->srr)
1086 		daddr = inet->opt->faddr;
1087 {
1088 	struct flowi fl = {
1089 		.oif = sk->sk_bound_dev_if,
1090 		.nl_u = {
1091 			.ip4_u = {
1092 				.daddr	= daddr,
1093 				.saddr	= inet->saddr,
1094 				.tos	= RT_CONN_FLAGS(sk),
1095 			},
1096 		},
1097 		.proto = sk->sk_protocol,
1098 		.uli_u = {
1099 			.ports = {
1100 				.sport = inet->sport,
1101 				.dport = inet->dport,
1102 			},
1103 		},
1104 	};
1105 
1106 	security_sk_classify_flow(sk, &fl);
1107 	err = ip_route_output_flow(&rt, &fl, sk, 0);
1108 }
1109 	if (!err)
1110 		sk_setup_caps(sk, &rt->u.dst);
1111 	else {
1112 		/* Routing failed... */
1113 		sk->sk_route_caps = 0;
1114 		/*
1115 		 * Other protocols have to map its equivalent state to TCP_SYN_SENT.
1116 		 * DCCP maps its DCCP_REQUESTING state to TCP_SYN_SENT. -acme
1117 		 */
1118 		if (!sysctl_ip_dynaddr ||
1119 		    sk->sk_state != TCP_SYN_SENT ||
1120 		    (sk->sk_userlocks & SOCK_BINDADDR_LOCK) ||
1121 		    (err = inet_sk_reselect_saddr(sk)) != 0)
1122 			sk->sk_err_soft = -err;
1123 	}
1124 
1125 	return err;
1126 }
1127 
1128 EXPORT_SYMBOL(inet_sk_rebuild_header);
1129 
1130 static int inet_gso_send_check(struct sk_buff *skb)
1131 {
1132 	struct iphdr *iph;
1133 	struct net_protocol *ops;
1134 	int proto;
1135 	int ihl;
1136 	int err = -EINVAL;
1137 
1138 	if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
1139 		goto out;
1140 
1141 	iph = ip_hdr(skb);
1142 	ihl = iph->ihl * 4;
1143 	if (ihl < sizeof(*iph))
1144 		goto out;
1145 
1146 	if (unlikely(!pskb_may_pull(skb, ihl)))
1147 		goto out;
1148 
1149 	__skb_pull(skb, ihl);
1150 	skb_reset_transport_header(skb);
1151 	iph = ip_hdr(skb);
1152 	proto = iph->protocol & (MAX_INET_PROTOS - 1);
1153 	err = -EPROTONOSUPPORT;
1154 
1155 	rcu_read_lock();
1156 	ops = rcu_dereference(inet_protos[proto]);
1157 	if (likely(ops && ops->gso_send_check))
1158 		err = ops->gso_send_check(skb);
1159 	rcu_read_unlock();
1160 
1161 out:
1162 	return err;
1163 }
1164 
1165 static struct sk_buff *inet_gso_segment(struct sk_buff *skb, int features)
1166 {
1167 	struct sk_buff *segs = ERR_PTR(-EINVAL);
1168 	struct iphdr *iph;
1169 	struct net_protocol *ops;
1170 	int proto;
1171 	int ihl;
1172 	int id;
1173 
1174 	if (unlikely(skb_shinfo(skb)->gso_type &
1175 		     ~(SKB_GSO_TCPV4 |
1176 		       SKB_GSO_UDP |
1177 		       SKB_GSO_DODGY |
1178 		       SKB_GSO_TCP_ECN |
1179 		       0)))
1180 		goto out;
1181 
1182 	if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
1183 		goto out;
1184 
1185 	iph = ip_hdr(skb);
1186 	ihl = iph->ihl * 4;
1187 	if (ihl < sizeof(*iph))
1188 		goto out;
1189 
1190 	if (unlikely(!pskb_may_pull(skb, ihl)))
1191 		goto out;
1192 
1193 	__skb_pull(skb, ihl);
1194 	skb_reset_transport_header(skb);
1195 	iph = ip_hdr(skb);
1196 	id = ntohs(iph->id);
1197 	proto = iph->protocol & (MAX_INET_PROTOS - 1);
1198 	segs = ERR_PTR(-EPROTONOSUPPORT);
1199 
1200 	rcu_read_lock();
1201 	ops = rcu_dereference(inet_protos[proto]);
1202 	if (likely(ops && ops->gso_segment))
1203 		segs = ops->gso_segment(skb, features);
1204 	rcu_read_unlock();
1205 
1206 	if (!segs || unlikely(IS_ERR(segs)))
1207 		goto out;
1208 
1209 	skb = segs;
1210 	do {
1211 		iph = ip_hdr(skb);
1212 		iph->id = htons(id++);
1213 		iph->tot_len = htons(skb->len - skb->mac_len);
1214 		iph->check = 0;
1215 		iph->check = ip_fast_csum(skb_network_header(skb), iph->ihl);
1216 	} while ((skb = skb->next));
1217 
1218 out:
1219 	return segs;
1220 }
1221 
1222 unsigned long snmp_fold_field(void *mib[], int offt)
1223 {
1224 	unsigned long res = 0;
1225 	int i;
1226 
1227 	for_each_possible_cpu(i) {
1228 		res += *(((unsigned long *) per_cpu_ptr(mib[0], i)) + offt);
1229 		res += *(((unsigned long *) per_cpu_ptr(mib[1], i)) + offt);
1230 	}
1231 	return res;
1232 }
1233 EXPORT_SYMBOL_GPL(snmp_fold_field);
1234 
1235 int snmp_mib_init(void *ptr[2], size_t mibsize, size_t mibalign)
1236 {
1237 	BUG_ON(ptr == NULL);
1238 	ptr[0] = __alloc_percpu(mibsize);
1239 	if (!ptr[0])
1240 		goto err0;
1241 	ptr[1] = __alloc_percpu(mibsize);
1242 	if (!ptr[1])
1243 		goto err1;
1244 	return 0;
1245 err1:
1246 	free_percpu(ptr[0]);
1247 	ptr[0] = NULL;
1248 err0:
1249 	return -ENOMEM;
1250 }
1251 EXPORT_SYMBOL_GPL(snmp_mib_init);
1252 
1253 void snmp_mib_free(void *ptr[2])
1254 {
1255 	BUG_ON(ptr == NULL);
1256 	free_percpu(ptr[0]);
1257 	free_percpu(ptr[1]);
1258 	ptr[0] = ptr[1] = NULL;
1259 }
1260 EXPORT_SYMBOL_GPL(snmp_mib_free);
1261 
1262 #ifdef CONFIG_IP_MULTICAST
1263 static struct net_protocol igmp_protocol = {
1264 	.handler =	igmp_rcv,
1265 };
1266 #endif
1267 
1268 static struct net_protocol tcp_protocol = {
1269 	.handler =	tcp_v4_rcv,
1270 	.err_handler =	tcp_v4_err,
1271 	.gso_send_check = tcp_v4_gso_send_check,
1272 	.gso_segment =	tcp_tso_segment,
1273 	.no_policy =	1,
1274 };
1275 
1276 static struct net_protocol udp_protocol = {
1277 	.handler =	udp_rcv,
1278 	.err_handler =	udp_err,
1279 	.no_policy =	1,
1280 };
1281 
1282 static struct net_protocol icmp_protocol = {
1283 	.handler =	icmp_rcv,
1284 };
1285 
1286 static int __init init_ipv4_mibs(void)
1287 {
1288 	if (snmp_mib_init((void **)net_statistics,
1289 			  sizeof(struct linux_mib),
1290 			  __alignof__(struct linux_mib)) < 0)
1291 		goto err_net_mib;
1292 	if (snmp_mib_init((void **)ip_statistics,
1293 			  sizeof(struct ipstats_mib),
1294 			  __alignof__(struct ipstats_mib)) < 0)
1295 		goto err_ip_mib;
1296 	if (snmp_mib_init((void **)icmp_statistics,
1297 			  sizeof(struct icmp_mib),
1298 			  __alignof__(struct icmp_mib)) < 0)
1299 		goto err_icmp_mib;
1300 	if (snmp_mib_init((void **)tcp_statistics,
1301 			  sizeof(struct tcp_mib),
1302 			  __alignof__(struct tcp_mib)) < 0)
1303 		goto err_tcp_mib;
1304 	if (snmp_mib_init((void **)udp_statistics,
1305 			  sizeof(struct udp_mib),
1306 			  __alignof__(struct udp_mib)) < 0)
1307 		goto err_udp_mib;
1308 	if (snmp_mib_init((void **)udplite_statistics,
1309 			  sizeof(struct udp_mib),
1310 			  __alignof__(struct udp_mib)) < 0)
1311 		goto err_udplite_mib;
1312 
1313 	tcp_mib_init();
1314 
1315 	return 0;
1316 
1317 err_udplite_mib:
1318 	snmp_mib_free((void **)udp_statistics);
1319 err_udp_mib:
1320 	snmp_mib_free((void **)tcp_statistics);
1321 err_tcp_mib:
1322 	snmp_mib_free((void **)icmp_statistics);
1323 err_icmp_mib:
1324 	snmp_mib_free((void **)ip_statistics);
1325 err_ip_mib:
1326 	snmp_mib_free((void **)net_statistics);
1327 err_net_mib:
1328 	return -ENOMEM;
1329 }
1330 
1331 static int ipv4_proc_init(void);
1332 
1333 /*
1334  *	IP protocol layer initialiser
1335  */
1336 
1337 static struct packet_type ip_packet_type = {
1338 	.type = __constant_htons(ETH_P_IP),
1339 	.func = ip_rcv,
1340 	.gso_send_check = inet_gso_send_check,
1341 	.gso_segment = inet_gso_segment,
1342 };
1343 
1344 static int __init inet_init(void)
1345 {
1346 	struct sk_buff *dummy_skb;
1347 	struct inet_protosw *q;
1348 	struct list_head *r;
1349 	int rc = -EINVAL;
1350 
1351 	BUILD_BUG_ON(sizeof(struct inet_skb_parm) > sizeof(dummy_skb->cb));
1352 
1353 	rc = proto_register(&tcp_prot, 1);
1354 	if (rc)
1355 		goto out;
1356 
1357 	rc = proto_register(&udp_prot, 1);
1358 	if (rc)
1359 		goto out_unregister_tcp_proto;
1360 
1361 	rc = proto_register(&raw_prot, 1);
1362 	if (rc)
1363 		goto out_unregister_udp_proto;
1364 
1365 	/*
1366 	 *	Tell SOCKET that we are alive...
1367 	 */
1368 
1369 	(void)sock_register(&inet_family_ops);
1370 
1371 	/*
1372 	 *	Add all the base protocols.
1373 	 */
1374 
1375 	if (inet_add_protocol(&icmp_protocol, IPPROTO_ICMP) < 0)
1376 		printk(KERN_CRIT "inet_init: Cannot add ICMP protocol\n");
1377 	if (inet_add_protocol(&udp_protocol, IPPROTO_UDP) < 0)
1378 		printk(KERN_CRIT "inet_init: Cannot add UDP protocol\n");
1379 	if (inet_add_protocol(&tcp_protocol, IPPROTO_TCP) < 0)
1380 		printk(KERN_CRIT "inet_init: Cannot add TCP protocol\n");
1381 #ifdef CONFIG_IP_MULTICAST
1382 	if (inet_add_protocol(&igmp_protocol, IPPROTO_IGMP) < 0)
1383 		printk(KERN_CRIT "inet_init: Cannot add IGMP protocol\n");
1384 #endif
1385 
1386 	/* Register the socket-side information for inet_create. */
1387 	for (r = &inetsw[0]; r < &inetsw[SOCK_MAX]; ++r)
1388 		INIT_LIST_HEAD(r);
1389 
1390 	for (q = inetsw_array; q < &inetsw_array[INETSW_ARRAY_LEN]; ++q)
1391 		inet_register_protosw(q);
1392 
1393 	/*
1394 	 *	Set the ARP module up
1395 	 */
1396 
1397 	arp_init();
1398 
1399 	/*
1400 	 *	Set the IP module up
1401 	 */
1402 
1403 	ip_init();
1404 
1405 	tcp_v4_init(&inet_family_ops);
1406 
1407 	/* Setup TCP slab cache for open requests. */
1408 	tcp_init();
1409 
1410 	/* Add UDP-Lite (RFC 3828) */
1411 	udplite4_register();
1412 
1413 	/*
1414 	 *	Set the ICMP layer up
1415 	 */
1416 
1417 	icmp_init(&inet_family_ops);
1418 
1419 	/*
1420 	 *	Initialise the multicast router
1421 	 */
1422 #if defined(CONFIG_IP_MROUTE)
1423 	ip_mr_init();
1424 #endif
1425 	/*
1426 	 *	Initialise per-cpu ipv4 mibs
1427 	 */
1428 
1429 	if (init_ipv4_mibs())
1430 		printk(KERN_CRIT "inet_init: Cannot init ipv4 mibs\n"); ;
1431 
1432 	ipv4_proc_init();
1433 
1434 	ipfrag_init();
1435 
1436 	dev_add_pack(&ip_packet_type);
1437 
1438 	rc = 0;
1439 out:
1440 	return rc;
1441 out_unregister_udp_proto:
1442 	proto_unregister(&udp_prot);
1443 out_unregister_tcp_proto:
1444 	proto_unregister(&tcp_prot);
1445 	goto out;
1446 }
1447 
1448 fs_initcall(inet_init);
1449 
1450 /* ------------------------------------------------------------------------ */
1451 
1452 #ifdef CONFIG_PROC_FS
1453 static int __init ipv4_proc_init(void)
1454 {
1455 	int rc = 0;
1456 
1457 	if (raw_proc_init())
1458 		goto out_raw;
1459 	if (tcp4_proc_init())
1460 		goto out_tcp;
1461 	if (udp4_proc_init())
1462 		goto out_udp;
1463 	if (fib_proc_init())
1464 		goto out_fib;
1465 	if (ip_misc_proc_init())
1466 		goto out_misc;
1467 out:
1468 	return rc;
1469 out_misc:
1470 	fib_proc_exit();
1471 out_fib:
1472 	udp4_proc_exit();
1473 out_udp:
1474 	tcp4_proc_exit();
1475 out_tcp:
1476 	raw_proc_exit();
1477 out_raw:
1478 	rc = -ENOMEM;
1479 	goto out;
1480 }
1481 
1482 #else /* CONFIG_PROC_FS */
1483 static int __init ipv4_proc_init(void)
1484 {
1485 	return 0;
1486 }
1487 #endif /* CONFIG_PROC_FS */
1488 
1489 MODULE_ALIAS_NETPROTO(PF_INET);
1490 
1491 EXPORT_SYMBOL(inet_accept);
1492 EXPORT_SYMBOL(inet_bind);
1493 EXPORT_SYMBOL(inet_dgram_connect);
1494 EXPORT_SYMBOL(inet_dgram_ops);
1495 EXPORT_SYMBOL(inet_getname);
1496 EXPORT_SYMBOL(inet_ioctl);
1497 EXPORT_SYMBOL(inet_listen);
1498 EXPORT_SYMBOL(inet_register_protosw);
1499 EXPORT_SYMBOL(inet_release);
1500 EXPORT_SYMBOL(inet_sendmsg);
1501 EXPORT_SYMBOL(inet_shutdown);
1502 EXPORT_SYMBOL(inet_sock_destruct);
1503 EXPORT_SYMBOL(inet_stream_connect);
1504 EXPORT_SYMBOL(inet_stream_ops);
1505 EXPORT_SYMBOL(inet_unregister_protosw);
1506 EXPORT_SYMBOL(net_statistics);
1507 EXPORT_SYMBOL(sysctl_ip_nonlocal_bind);
1508