af_inet.c revision 2307f866f542f3397d24f78d0efd74f4ab214a96
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#include <linux/err.h>
69#include <linux/errno.h>
70#include <linux/types.h>
71#include <linux/socket.h>
72#include <linux/in.h>
73#include <linux/kernel.h>
74#include <linux/module.h>
75#include <linux/sched.h>
76#include <linux/timer.h>
77#include <linux/string.h>
78#include <linux/sockios.h>
79#include <linux/net.h>
80#include <linux/capability.h>
81#include <linux/fcntl.h>
82#include <linux/mm.h>
83#include <linux/interrupt.h>
84#include <linux/stat.h>
85#include <linux/init.h>
86#include <linux/poll.h>
87#include <linux/netfilter_ipv4.h>
88#include <linux/random.h>
89
90#include <asm/uaccess.h>
91#include <asm/system.h>
92
93#include <linux/inet.h>
94#include <linux/igmp.h>
95#include <linux/inetdevice.h>
96#include <linux/netdevice.h>
97#include <net/checksum.h>
98#include <net/ip.h>
99#include <net/protocol.h>
100#include <net/arp.h>
101#include <net/route.h>
102#include <net/ip_fib.h>
103#include <net/inet_connection_sock.h>
104#include <net/tcp.h>
105#include <net/udp.h>
106#include <net/udplite.h>
107#include <linux/skbuff.h>
108#include <net/sock.h>
109#include <net/raw.h>
110#include <net/icmp.h>
111#include <net/ipip.h>
112#include <net/inet_common.h>
113#include <net/xfrm.h>
114#include <net/net_namespace.h>
115#ifdef CONFIG_IP_MROUTE
116#include <linux/mroute.h>
117#endif
118
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
126struct ipv4_config ipv4_config;
127
128EXPORT_SYMBOL(ipv4_config);
129
130/* New destruction routine */
131
132void inet_sock_destruct(struct sock *sk)
133{
134	struct inet_sock *inet = inet_sk(sk);
135
136	__skb_queue_purge(&sk->sk_receive_queue);
137	__skb_queue_purge(&sk->sk_error_queue);
138
139	sk_mem_reclaim(sk);
140
141	if (sk->sk_type == SOCK_STREAM && sk->sk_state != TCP_CLOSE) {
142		printk("Attempt to release TCP socket in state %d %p\n",
143		       sk->sk_state, sk);
144		return;
145	}
146	if (!sock_flag(sk, SOCK_DEAD)) {
147		printk("Attempt to release alive inet socket %p\n", sk);
148		return;
149	}
150
151	WARN_ON(atomic_read(&sk->sk_rmem_alloc));
152	WARN_ON(atomic_read(&sk->sk_wmem_alloc));
153	WARN_ON(sk->sk_wmem_queued);
154	WARN_ON(sk->sk_forward_alloc);
155
156	kfree(inet->opt);
157	dst_release(sk->sk_dst_cache);
158	sk_refcnt_debug_dec(sk);
159}
160
161/*
162 *	The routines beyond this point handle the behaviour of an AF_INET
163 *	socket object. Mostly it punts to the subprotocols of IP to do
164 *	the work.
165 */
166
167/*
168 *	Automatically bind an unbound socket.
169 */
170
171static int inet_autobind(struct sock *sk)
172{
173	struct inet_sock *inet;
174	/* We may need to bind the socket. */
175	lock_sock(sk);
176	inet = inet_sk(sk);
177	if (!inet->num) {
178		if (sk->sk_prot->get_port(sk, 0)) {
179			release_sock(sk);
180			return -EAGAIN;
181		}
182		inet->sport = htons(inet->num);
183	}
184	release_sock(sk);
185	return 0;
186}
187
188/*
189 *	Move a socket into listening state.
190 */
191int inet_listen(struct socket *sock, int backlog)
192{
193	struct sock *sk = sock->sk;
194	unsigned char old_state;
195	int err;
196
197	lock_sock(sk);
198
199	err = -EINVAL;
200	if (sock->state != SS_UNCONNECTED || sock->type != SOCK_STREAM)
201		goto out;
202
203	old_state = sk->sk_state;
204	if (!((1 << old_state) & (TCPF_CLOSE | TCPF_LISTEN)))
205		goto out;
206
207	/* Really, if the socket is already in listen state
208	 * we can only allow the backlog to be adjusted.
209	 */
210	if (old_state != TCP_LISTEN) {
211		err = inet_csk_listen_start(sk, backlog);
212		if (err)
213			goto out;
214	}
215	sk->sk_max_ack_backlog = backlog;
216	err = 0;
217
218out:
219	release_sock(sk);
220	return err;
221}
222
223u32 inet_ehash_secret __read_mostly;
224EXPORT_SYMBOL(inet_ehash_secret);
225
226/*
227 * inet_ehash_secret must be set exactly once
228 * Instead of using a dedicated spinlock, we (ab)use inetsw_lock
229 */
230void build_ehash_secret(void)
231{
232	u32 rnd;
233	do {
234		get_random_bytes(&rnd, sizeof(rnd));
235	} while (rnd == 0);
236	spin_lock_bh(&inetsw_lock);
237	if (!inet_ehash_secret)
238		inet_ehash_secret = rnd;
239	spin_unlock_bh(&inetsw_lock);
240}
241EXPORT_SYMBOL(build_ehash_secret);
242
243static inline int inet_netns_ok(struct net *net, int protocol)
244{
245	int hash;
246	struct net_protocol *ipprot;
247
248	if (net_eq(net, &init_net))
249		return 1;
250
251	hash = protocol & (MAX_INET_PROTOS - 1);
252	ipprot = rcu_dereference(inet_protos[hash]);
253
254	if (ipprot == NULL)
255		/* raw IP is OK */
256		return 1;
257	return ipprot->netns_ok;
258}
259
260/*
261 *	Create an inet socket.
262 */
263
264static int inet_create(struct net *net, struct socket *sock, int protocol)
265{
266	struct sock *sk;
267	struct inet_protosw *answer;
268	struct inet_sock *inet;
269	struct proto *answer_prot;
270	unsigned char answer_flags;
271	char answer_no_check;
272	int try_loading_module = 0;
273	int err;
274
275	if (unlikely(!inet_ehash_secret))
276		if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM)
277			build_ehash_secret();
278
279	sock->state = SS_UNCONNECTED;
280
281	/* Look for the requested type/protocol pair. */
282lookup_protocol:
283	err = -ESOCKTNOSUPPORT;
284	rcu_read_lock();
285	list_for_each_entry_rcu(answer, &inetsw[sock->type], list) {
286
287		err = 0;
288		/* Check the non-wild match. */
289		if (protocol == answer->protocol) {
290			if (protocol != IPPROTO_IP)
291				break;
292		} else {
293			/* Check for the two wild cases. */
294			if (IPPROTO_IP == protocol) {
295				protocol = answer->protocol;
296				break;
297			}
298			if (IPPROTO_IP == answer->protocol)
299				break;
300		}
301		err = -EPROTONOSUPPORT;
302	}
303
304	if (unlikely(err)) {
305		if (try_loading_module < 2) {
306			rcu_read_unlock();
307			/*
308			 * Be more specific, e.g. net-pf-2-proto-132-type-1
309			 * (net-pf-PF_INET-proto-IPPROTO_SCTP-type-SOCK_STREAM)
310			 */
311			if (++try_loading_module == 1)
312				request_module("net-pf-%d-proto-%d-type-%d",
313					       PF_INET, protocol, sock->type);
314			/*
315			 * Fall back to generic, e.g. net-pf-2-proto-132
316			 * (net-pf-PF_INET-proto-IPPROTO_SCTP)
317			 */
318			else
319				request_module("net-pf-%d-proto-%d",
320					       PF_INET, protocol);
321			goto lookup_protocol;
322		} else
323			goto out_rcu_unlock;
324	}
325
326	err = -EPERM;
327	if (answer->capability > 0 && !capable(answer->capability))
328		goto out_rcu_unlock;
329
330	err = -EAFNOSUPPORT;
331	if (!inet_netns_ok(net, protocol))
332		goto out_rcu_unlock;
333
334	sock->ops = answer->ops;
335	answer_prot = answer->prot;
336	answer_no_check = answer->no_check;
337	answer_flags = answer->flags;
338	rcu_read_unlock();
339
340	WARN_ON(answer_prot->slab == NULL);
341
342	err = -ENOBUFS;
343	sk = sk_alloc(net, PF_INET, GFP_KERNEL, answer_prot);
344	if (sk == NULL)
345		goto out;
346
347	err = 0;
348	sk->sk_no_check = answer_no_check;
349	if (INET_PROTOSW_REUSE & answer_flags)
350		sk->sk_reuse = 1;
351
352	inet = inet_sk(sk);
353	inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
354
355	if (SOCK_RAW == sock->type) {
356		inet->num = protocol;
357		if (IPPROTO_RAW == protocol)
358			inet->hdrincl = 1;
359	}
360
361	if (ipv4_config.no_pmtu_disc)
362		inet->pmtudisc = IP_PMTUDISC_DONT;
363	else
364		inet->pmtudisc = IP_PMTUDISC_WANT;
365
366	inet->id = 0;
367
368	sock_init_data(sock, sk);
369
370	sk->sk_destruct	   = inet_sock_destruct;
371	sk->sk_protocol	   = protocol;
372	sk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
373
374	inet->uc_ttl	= -1;
375	inet->mc_loop	= 1;
376	inet->mc_ttl	= 1;
377	inet->mc_all	= 1;
378	inet->mc_index	= 0;
379	inet->mc_list	= NULL;
380
381	sk_refcnt_debug_inc(sk);
382
383	if (inet->num) {
384		/* It assumes that any protocol which allows
385		 * the user to assign a number at socket
386		 * creation time automatically
387		 * shares.
388		 */
389		inet->sport = htons(inet->num);
390		/* Add to protocol hash chains. */
391		sk->sk_prot->hash(sk);
392	}
393
394	if (sk->sk_prot->init) {
395		err = sk->sk_prot->init(sk);
396		if (err)
397			sk_common_release(sk);
398	}
399out:
400	return err;
401out_rcu_unlock:
402	rcu_read_unlock();
403	goto out;
404}
405
406
407/*
408 *	The peer socket should always be NULL (or else). When we call this
409 *	function we are destroying the object and from then on nobody
410 *	should refer to it.
411 */
412int inet_release(struct socket *sock)
413{
414	struct sock *sk = sock->sk;
415
416	if (sk) {
417		long timeout;
418
419		/* Applications forget to leave groups before exiting */
420		ip_mc_drop_socket(sk);
421
422		/* If linger is set, we don't return until the close
423		 * is complete.  Otherwise we return immediately. The
424		 * actually closing is done the same either way.
425		 *
426		 * If the close is due to the process exiting, we never
427		 * linger..
428		 */
429		timeout = 0;
430		if (sock_flag(sk, SOCK_LINGER) &&
431		    !(current->flags & PF_EXITING))
432			timeout = sk->sk_lingertime;
433		sock->sk = NULL;
434		sk->sk_prot->close(sk, timeout);
435	}
436	return 0;
437}
438
439/* It is off by default, see below. */
440int sysctl_ip_nonlocal_bind __read_mostly;
441
442int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
443{
444	struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
445	struct sock *sk = sock->sk;
446	struct inet_sock *inet = inet_sk(sk);
447	unsigned short snum;
448	int chk_addr_ret;
449	int err;
450
451	/* If the socket has its own bind function then use it. (RAW) */
452	if (sk->sk_prot->bind) {
453		err = sk->sk_prot->bind(sk, uaddr, addr_len);
454		goto out;
455	}
456	err = -EINVAL;
457	if (addr_len < sizeof(struct sockaddr_in))
458		goto out;
459
460	chk_addr_ret = inet_addr_type(sock_net(sk), addr->sin_addr.s_addr);
461
462	/* Not specified by any standard per-se, however it breaks too
463	 * many applications when removed.  It is unfortunate since
464	 * allowing applications to make a non-local bind solves
465	 * several problems with systems using dynamic addressing.
466	 * (ie. your servers still start up even if your ISDN link
467	 *  is temporarily down)
468	 */
469	err = -EADDRNOTAVAIL;
470	if (!sysctl_ip_nonlocal_bind &&
471	    !(inet->freebind || inet->transparent) &&
472	    addr->sin_addr.s_addr != htonl(INADDR_ANY) &&
473	    chk_addr_ret != RTN_LOCAL &&
474	    chk_addr_ret != RTN_MULTICAST &&
475	    chk_addr_ret != RTN_BROADCAST)
476		goto out;
477
478	snum = ntohs(addr->sin_port);
479	err = -EACCES;
480	if (snum && snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
481		goto out;
482
483	/*      We keep a pair of addresses. rcv_saddr is the one
484	 *      used by hash lookups, and saddr is used for transmit.
485	 *
486	 *      In the BSD API these are the same except where it
487	 *      would be illegal to use them (multicast/broadcast) in
488	 *      which case the sending device address is used.
489	 */
490	lock_sock(sk);
491
492	/* Check these errors (active socket, double bind). */
493	err = -EINVAL;
494	if (sk->sk_state != TCP_CLOSE || inet->num)
495		goto out_release_sock;
496
497	inet->rcv_saddr = inet->saddr = addr->sin_addr.s_addr;
498	if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST)
499		inet->saddr = 0;  /* Use device */
500
501	/* Make sure we are allowed to bind here. */
502	if (sk->sk_prot->get_port(sk, snum)) {
503		inet->saddr = inet->rcv_saddr = 0;
504		err = -EADDRINUSE;
505		goto out_release_sock;
506	}
507
508	if (inet->rcv_saddr)
509		sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
510	if (snum)
511		sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
512	inet->sport = htons(inet->num);
513	inet->daddr = 0;
514	inet->dport = 0;
515	sk_dst_reset(sk);
516	err = 0;
517out_release_sock:
518	release_sock(sk);
519out:
520	return err;
521}
522
523int 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 (uaddr->sa_family == AF_UNSPEC)
529		return sk->sk_prot->disconnect(sk, flags);
530
531	if (!inet_sk(sk)->num && inet_autobind(sk))
532		return -EAGAIN;
533	return sk->sk_prot->connect(sk, (struct sockaddr *)uaddr, addr_len);
534}
535
536static long inet_wait_for_connect(struct sock *sk, long timeo)
537{
538	DEFINE_WAIT(wait);
539
540	prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
541
542	/* Basic assumption: if someone sets sk->sk_err, he _must_
543	 * change state of the socket from TCP_SYN_*.
544	 * Connect() does not allow to get error notifications
545	 * without closing the socket.
546	 */
547	while ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
548		release_sock(sk);
549		timeo = schedule_timeout(timeo);
550		lock_sock(sk);
551		if (signal_pending(current) || !timeo)
552			break;
553		prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
554	}
555	finish_wait(sk->sk_sleep, &wait);
556	return timeo;
557}
558
559/*
560 *	Connect to a remote host. There is regrettably still a little
561 *	TCP 'magic' in here.
562 */
563int inet_stream_connect(struct socket *sock, struct sockaddr *uaddr,
564			int addr_len, int flags)
565{
566	struct sock *sk = sock->sk;
567	int err;
568	long timeo;
569
570	lock_sock(sk);
571
572	if (uaddr->sa_family == AF_UNSPEC) {
573		err = sk->sk_prot->disconnect(sk, flags);
574		sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
575		goto out;
576	}
577
578	switch (sock->state) {
579	default:
580		err = -EINVAL;
581		goto out;
582	case SS_CONNECTED:
583		err = -EISCONN;
584		goto out;
585	case SS_CONNECTING:
586		err = -EALREADY;
587		/* Fall out of switch with err, set for this state */
588		break;
589	case SS_UNCONNECTED:
590		err = -EISCONN;
591		if (sk->sk_state != TCP_CLOSE)
592			goto out;
593
594		err = sk->sk_prot->connect(sk, uaddr, addr_len);
595		if (err < 0)
596			goto out;
597
598		sock->state = SS_CONNECTING;
599
600		/* Just entered SS_CONNECTING state; the only
601		 * difference is that return value in non-blocking
602		 * case is EINPROGRESS, rather than EALREADY.
603		 */
604		err = -EINPROGRESS;
605		break;
606	}
607
608	timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
609
610	if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
611		/* Error code is set above */
612		if (!timeo || !inet_wait_for_connect(sk, timeo))
613			goto out;
614
615		err = sock_intr_errno(timeo);
616		if (signal_pending(current))
617			goto out;
618	}
619
620	/* Connection was closed by RST, timeout, ICMP error
621	 * or another process disconnected us.
622	 */
623	if (sk->sk_state == TCP_CLOSE)
624		goto sock_error;
625
626	/* sk->sk_err may be not zero now, if RECVERR was ordered by user
627	 * and error was received after socket entered established state.
628	 * Hence, it is handled normally after connect() return successfully.
629	 */
630
631	sock->state = SS_CONNECTED;
632	err = 0;
633out:
634	release_sock(sk);
635	return err;
636
637sock_error:
638	err = sock_error(sk) ? : -ECONNABORTED;
639	sock->state = SS_UNCONNECTED;
640	if (sk->sk_prot->disconnect(sk, flags))
641		sock->state = SS_DISCONNECTING;
642	goto out;
643}
644
645/*
646 *	Accept a pending connection. The TCP layer now gives BSD semantics.
647 */
648
649int inet_accept(struct socket *sock, struct socket *newsock, int flags)
650{
651	struct sock *sk1 = sock->sk;
652	int err = -EINVAL;
653	struct sock *sk2 = sk1->sk_prot->accept(sk1, flags, &err);
654
655	if (!sk2)
656		goto do_err;
657
658	lock_sock(sk2);
659
660	WARN_ON(!((1 << sk2->sk_state) &
661		  (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT | TCPF_CLOSE)));
662
663	sock_graft(sk2, newsock);
664
665	newsock->state = SS_CONNECTED;
666	err = 0;
667	release_sock(sk2);
668do_err:
669	return err;
670}
671
672
673/*
674 *	This does both peername and sockname.
675 */
676int inet_getname(struct socket *sock, struct sockaddr *uaddr,
677			int *uaddr_len, int peer)
678{
679	struct sock *sk		= sock->sk;
680	struct inet_sock *inet	= inet_sk(sk);
681	struct sockaddr_in *sin	= (struct sockaddr_in *)uaddr;
682
683	sin->sin_family = AF_INET;
684	if (peer) {
685		if (!inet->dport ||
686		    (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
687		     peer == 1))
688			return -ENOTCONN;
689		sin->sin_port = inet->dport;
690		sin->sin_addr.s_addr = inet->daddr;
691	} else {
692		__be32 addr = inet->rcv_saddr;
693		if (!addr)
694			addr = inet->saddr;
695		sin->sin_port = inet->sport;
696		sin->sin_addr.s_addr = addr;
697	}
698	memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
699	*uaddr_len = sizeof(*sin);
700	return 0;
701}
702
703int inet_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
704		 size_t size)
705{
706	struct sock *sk = sock->sk;
707
708	/* We may need to bind the socket. */
709	if (!inet_sk(sk)->num && inet_autobind(sk))
710		return -EAGAIN;
711
712	return sk->sk_prot->sendmsg(iocb, sk, msg, size);
713}
714
715
716static ssize_t inet_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
717{
718	struct sock *sk = sock->sk;
719
720	/* We may need to bind the socket. */
721	if (!inet_sk(sk)->num && inet_autobind(sk))
722		return -EAGAIN;
723
724	if (sk->sk_prot->sendpage)
725		return sk->sk_prot->sendpage(sk, page, offset, size, flags);
726	return sock_no_sendpage(sock, page, offset, size, flags);
727}
728
729
730int inet_shutdown(struct socket *sock, int how)
731{
732	struct sock *sk = sock->sk;
733	int err = 0;
734
735	/* This should really check to make sure
736	 * the socket is a TCP socket. (WHY AC...)
737	 */
738	how++; /* maps 0->1 has the advantage of making bit 1 rcvs and
739		       1->2 bit 2 snds.
740		       2->3 */
741	if ((how & ~SHUTDOWN_MASK) || !how)	/* MAXINT->0 */
742		return -EINVAL;
743
744	lock_sock(sk);
745	if (sock->state == SS_CONNECTING) {
746		if ((1 << sk->sk_state) &
747		    (TCPF_SYN_SENT | TCPF_SYN_RECV | TCPF_CLOSE))
748			sock->state = SS_DISCONNECTING;
749		else
750			sock->state = SS_CONNECTED;
751	}
752
753	switch (sk->sk_state) {
754	case TCP_CLOSE:
755		err = -ENOTCONN;
756		/* Hack to wake up other listeners, who can poll for
757		   POLLHUP, even on eg. unconnected UDP sockets -- RR */
758	default:
759		sk->sk_shutdown |= how;
760		if (sk->sk_prot->shutdown)
761			sk->sk_prot->shutdown(sk, how);
762		break;
763
764	/* Remaining two branches are temporary solution for missing
765	 * close() in multithreaded environment. It is _not_ a good idea,
766	 * but we have no choice until close() is repaired at VFS level.
767	 */
768	case TCP_LISTEN:
769		if (!(how & RCV_SHUTDOWN))
770			break;
771		/* Fall through */
772	case TCP_SYN_SENT:
773		err = sk->sk_prot->disconnect(sk, O_NONBLOCK);
774		sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
775		break;
776	}
777
778	/* Wake up anyone sleeping in poll. */
779	sk->sk_state_change(sk);
780	release_sock(sk);
781	return err;
782}
783
784/*
785 *	ioctl() calls you can issue on an INET socket. Most of these are
786 *	device configuration and stuff and very rarely used. Some ioctls
787 *	pass on to the socket itself.
788 *
789 *	NOTE: I like the idea of a module for the config stuff. ie ifconfig
790 *	loads the devconfigure module does its configuring and unloads it.
791 *	There's a good 20K of config code hanging around the kernel.
792 */
793
794int inet_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
795{
796	struct sock *sk = sock->sk;
797	int err = 0;
798	struct net *net = sock_net(sk);
799
800	switch (cmd) {
801		case SIOCGSTAMP:
802			err = sock_get_timestamp(sk, (struct timeval __user *)arg);
803			break;
804		case SIOCGSTAMPNS:
805			err = sock_get_timestampns(sk, (struct timespec __user *)arg);
806			break;
807		case SIOCADDRT:
808		case SIOCDELRT:
809		case SIOCRTMSG:
810			err = ip_rt_ioctl(net, cmd, (void __user *)arg);
811			break;
812		case SIOCDARP:
813		case SIOCGARP:
814		case SIOCSARP:
815			err = arp_ioctl(net, cmd, (void __user *)arg);
816			break;
817		case SIOCGIFADDR:
818		case SIOCSIFADDR:
819		case SIOCGIFBRDADDR:
820		case SIOCSIFBRDADDR:
821		case SIOCGIFNETMASK:
822		case SIOCSIFNETMASK:
823		case SIOCGIFDSTADDR:
824		case SIOCSIFDSTADDR:
825		case SIOCSIFPFLAGS:
826		case SIOCGIFPFLAGS:
827		case SIOCSIFFLAGS:
828			err = devinet_ioctl(net, cmd, (void __user *)arg);
829			break;
830		default:
831			if (sk->sk_prot->ioctl)
832				err = sk->sk_prot->ioctl(sk, cmd, arg);
833			else
834				err = -ENOIOCTLCMD;
835			break;
836	}
837	return err;
838}
839
840const struct proto_ops inet_stream_ops = {
841	.family		   = PF_INET,
842	.owner		   = THIS_MODULE,
843	.release	   = inet_release,
844	.bind		   = inet_bind,
845	.connect	   = inet_stream_connect,
846	.socketpair	   = sock_no_socketpair,
847	.accept		   = inet_accept,
848	.getname	   = inet_getname,
849	.poll		   = tcp_poll,
850	.ioctl		   = inet_ioctl,
851	.listen		   = inet_listen,
852	.shutdown	   = inet_shutdown,
853	.setsockopt	   = sock_common_setsockopt,
854	.getsockopt	   = sock_common_getsockopt,
855	.sendmsg	   = tcp_sendmsg,
856	.recvmsg	   = sock_common_recvmsg,
857	.mmap		   = sock_no_mmap,
858	.sendpage	   = tcp_sendpage,
859	.splice_read	   = tcp_splice_read,
860#ifdef CONFIG_COMPAT
861	.compat_setsockopt = compat_sock_common_setsockopt,
862	.compat_getsockopt = compat_sock_common_getsockopt,
863#endif
864};
865
866const struct proto_ops inet_dgram_ops = {
867	.family		   = PF_INET,
868	.owner		   = THIS_MODULE,
869	.release	   = inet_release,
870	.bind		   = inet_bind,
871	.connect	   = inet_dgram_connect,
872	.socketpair	   = sock_no_socketpair,
873	.accept		   = sock_no_accept,
874	.getname	   = inet_getname,
875	.poll		   = udp_poll,
876	.ioctl		   = inet_ioctl,
877	.listen		   = sock_no_listen,
878	.shutdown	   = inet_shutdown,
879	.setsockopt	   = sock_common_setsockopt,
880	.getsockopt	   = sock_common_getsockopt,
881	.sendmsg	   = inet_sendmsg,
882	.recvmsg	   = sock_common_recvmsg,
883	.mmap		   = sock_no_mmap,
884	.sendpage	   = inet_sendpage,
885#ifdef CONFIG_COMPAT
886	.compat_setsockopt = compat_sock_common_setsockopt,
887	.compat_getsockopt = compat_sock_common_getsockopt,
888#endif
889};
890
891/*
892 * For SOCK_RAW sockets; should be the same as inet_dgram_ops but without
893 * udp_poll
894 */
895static const struct proto_ops inet_sockraw_ops = {
896	.family		   = PF_INET,
897	.owner		   = THIS_MODULE,
898	.release	   = inet_release,
899	.bind		   = inet_bind,
900	.connect	   = inet_dgram_connect,
901	.socketpair	   = sock_no_socketpair,
902	.accept		   = sock_no_accept,
903	.getname	   = inet_getname,
904	.poll		   = datagram_poll,
905	.ioctl		   = inet_ioctl,
906	.listen		   = sock_no_listen,
907	.shutdown	   = inet_shutdown,
908	.setsockopt	   = sock_common_setsockopt,
909	.getsockopt	   = sock_common_getsockopt,
910	.sendmsg	   = inet_sendmsg,
911	.recvmsg	   = sock_common_recvmsg,
912	.mmap		   = sock_no_mmap,
913	.sendpage	   = inet_sendpage,
914#ifdef CONFIG_COMPAT
915	.compat_setsockopt = compat_sock_common_setsockopt,
916	.compat_getsockopt = compat_sock_common_getsockopt,
917#endif
918};
919
920static struct net_proto_family inet_family_ops = {
921	.family = PF_INET,
922	.create = inet_create,
923	.owner	= THIS_MODULE,
924};
925
926/* Upon startup we insert all the elements in inetsw_array[] into
927 * the linked list inetsw.
928 */
929static struct inet_protosw inetsw_array[] =
930{
931	{
932		.type =       SOCK_STREAM,
933		.protocol =   IPPROTO_TCP,
934		.prot =       &tcp_prot,
935		.ops =        &inet_stream_ops,
936		.capability = -1,
937		.no_check =   0,
938		.flags =      INET_PROTOSW_PERMANENT |
939			      INET_PROTOSW_ICSK,
940	},
941
942	{
943		.type =       SOCK_DGRAM,
944		.protocol =   IPPROTO_UDP,
945		.prot =       &udp_prot,
946		.ops =        &inet_dgram_ops,
947		.capability = -1,
948		.no_check =   UDP_CSUM_DEFAULT,
949		.flags =      INET_PROTOSW_PERMANENT,
950       },
951
952
953       {
954	       .type =       SOCK_RAW,
955	       .protocol =   IPPROTO_IP,	/* wild card */
956	       .prot =       &raw_prot,
957	       .ops =        &inet_sockraw_ops,
958	       .capability = CAP_NET_RAW,
959	       .no_check =   UDP_CSUM_DEFAULT,
960	       .flags =      INET_PROTOSW_REUSE,
961       }
962};
963
964#define INETSW_ARRAY_LEN ARRAY_SIZE(inetsw_array)
965
966void inet_register_protosw(struct inet_protosw *p)
967{
968	struct list_head *lh;
969	struct inet_protosw *answer;
970	int protocol = p->protocol;
971	struct list_head *last_perm;
972
973	spin_lock_bh(&inetsw_lock);
974
975	if (p->type >= SOCK_MAX)
976		goto out_illegal;
977
978	/* If we are trying to override a permanent protocol, bail. */
979	answer = NULL;
980	last_perm = &inetsw[p->type];
981	list_for_each(lh, &inetsw[p->type]) {
982		answer = list_entry(lh, struct inet_protosw, list);
983
984		/* Check only the non-wild match. */
985		if (INET_PROTOSW_PERMANENT & answer->flags) {
986			if (protocol == answer->protocol)
987				break;
988			last_perm = lh;
989		}
990
991		answer = NULL;
992	}
993	if (answer)
994		goto out_permanent;
995
996	/* Add the new entry after the last permanent entry if any, so that
997	 * the new entry does not override a permanent entry when matched with
998	 * a wild-card protocol. But it is allowed to override any existing
999	 * non-permanent entry.  This means that when we remove this entry, the
1000	 * system automatically returns to the old behavior.
1001	 */
1002	list_add_rcu(&p->list, last_perm);
1003out:
1004	spin_unlock_bh(&inetsw_lock);
1005
1006	return;
1007
1008out_permanent:
1009	printk(KERN_ERR "Attempt to override permanent protocol %d.\n",
1010	       protocol);
1011	goto out;
1012
1013out_illegal:
1014	printk(KERN_ERR
1015	       "Ignoring attempt to register invalid socket type %d.\n",
1016	       p->type);
1017	goto out;
1018}
1019
1020void inet_unregister_protosw(struct inet_protosw *p)
1021{
1022	if (INET_PROTOSW_PERMANENT & p->flags) {
1023		printk(KERN_ERR
1024		       "Attempt to unregister permanent protocol %d.\n",
1025		       p->protocol);
1026	} else {
1027		spin_lock_bh(&inetsw_lock);
1028		list_del_rcu(&p->list);
1029		spin_unlock_bh(&inetsw_lock);
1030
1031		synchronize_net();
1032	}
1033}
1034
1035/*
1036 *      Shall we try to damage output packets if routing dev changes?
1037 */
1038
1039int sysctl_ip_dynaddr __read_mostly;
1040
1041static int inet_sk_reselect_saddr(struct sock *sk)
1042{
1043	struct inet_sock *inet = inet_sk(sk);
1044	int err;
1045	struct rtable *rt;
1046	__be32 old_saddr = inet->saddr;
1047	__be32 new_saddr;
1048	__be32 daddr = inet->daddr;
1049
1050	if (inet->opt && inet->opt->srr)
1051		daddr = inet->opt->faddr;
1052
1053	/* Query new route. */
1054	err = ip_route_connect(&rt, daddr, 0,
1055			       RT_CONN_FLAGS(sk),
1056			       sk->sk_bound_dev_if,
1057			       sk->sk_protocol,
1058			       inet->sport, inet->dport, sk, 0);
1059	if (err)
1060		return err;
1061
1062	sk_setup_caps(sk, &rt->u.dst);
1063
1064	new_saddr = rt->rt_src;
1065
1066	if (new_saddr == old_saddr)
1067		return 0;
1068
1069	if (sysctl_ip_dynaddr > 1) {
1070		printk(KERN_INFO "%s(): shifting inet->saddr from %pI4 to %pI4\n",
1071		       __func__, &old_saddr, &new_saddr);
1072	}
1073
1074	inet->saddr = inet->rcv_saddr = new_saddr;
1075
1076	/*
1077	 * XXX The only one ugly spot where we need to
1078	 * XXX really change the sockets identity after
1079	 * XXX it has entered the hashes. -DaveM
1080	 *
1081	 * Besides that, it does not check for connection
1082	 * uniqueness. Wait for troubles.
1083	 */
1084	__sk_prot_rehash(sk);
1085	return 0;
1086}
1087
1088int inet_sk_rebuild_header(struct sock *sk)
1089{
1090	struct inet_sock *inet = inet_sk(sk);
1091	struct rtable *rt = (struct rtable *)__sk_dst_check(sk, 0);
1092	__be32 daddr;
1093	int err;
1094
1095	/* Route is OK, nothing to do. */
1096	if (rt)
1097		return 0;
1098
1099	/* Reroute. */
1100	daddr = inet->daddr;
1101	if (inet->opt && inet->opt->srr)
1102		daddr = inet->opt->faddr;
1103{
1104	struct flowi fl = {
1105		.oif = sk->sk_bound_dev_if,
1106		.nl_u = {
1107			.ip4_u = {
1108				.daddr	= daddr,
1109				.saddr	= inet->saddr,
1110				.tos	= RT_CONN_FLAGS(sk),
1111			},
1112		},
1113		.proto = sk->sk_protocol,
1114		.flags = inet_sk_flowi_flags(sk),
1115		.uli_u = {
1116			.ports = {
1117				.sport = inet->sport,
1118				.dport = inet->dport,
1119			},
1120		},
1121	};
1122
1123	security_sk_classify_flow(sk, &fl);
1124	err = ip_route_output_flow(sock_net(sk), &rt, &fl, sk, 0);
1125}
1126	if (!err)
1127		sk_setup_caps(sk, &rt->u.dst);
1128	else {
1129		/* Routing failed... */
1130		sk->sk_route_caps = 0;
1131		/*
1132		 * Other protocols have to map its equivalent state to TCP_SYN_SENT.
1133		 * DCCP maps its DCCP_REQUESTING state to TCP_SYN_SENT. -acme
1134		 */
1135		if (!sysctl_ip_dynaddr ||
1136		    sk->sk_state != TCP_SYN_SENT ||
1137		    (sk->sk_userlocks & SOCK_BINDADDR_LOCK) ||
1138		    (err = inet_sk_reselect_saddr(sk)) != 0)
1139			sk->sk_err_soft = -err;
1140	}
1141
1142	return err;
1143}
1144
1145EXPORT_SYMBOL(inet_sk_rebuild_header);
1146
1147static int inet_gso_send_check(struct sk_buff *skb)
1148{
1149	struct iphdr *iph;
1150	struct net_protocol *ops;
1151	int proto;
1152	int ihl;
1153	int err = -EINVAL;
1154
1155	if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
1156		goto out;
1157
1158	iph = ip_hdr(skb);
1159	ihl = iph->ihl * 4;
1160	if (ihl < sizeof(*iph))
1161		goto out;
1162
1163	if (unlikely(!pskb_may_pull(skb, ihl)))
1164		goto out;
1165
1166	__skb_pull(skb, ihl);
1167	skb_reset_transport_header(skb);
1168	iph = ip_hdr(skb);
1169	proto = iph->protocol & (MAX_INET_PROTOS - 1);
1170	err = -EPROTONOSUPPORT;
1171
1172	rcu_read_lock();
1173	ops = rcu_dereference(inet_protos[proto]);
1174	if (likely(ops && ops->gso_send_check))
1175		err = ops->gso_send_check(skb);
1176	rcu_read_unlock();
1177
1178out:
1179	return err;
1180}
1181
1182static struct sk_buff *inet_gso_segment(struct sk_buff *skb, int features)
1183{
1184	struct sk_buff *segs = ERR_PTR(-EINVAL);
1185	struct iphdr *iph;
1186	struct net_protocol *ops;
1187	int proto;
1188	int ihl;
1189	int id;
1190
1191	if (!(features & NETIF_F_V4_CSUM))
1192		features &= ~NETIF_F_SG;
1193
1194	if (unlikely(skb_shinfo(skb)->gso_type &
1195		     ~(SKB_GSO_TCPV4 |
1196		       SKB_GSO_UDP |
1197		       SKB_GSO_DODGY |
1198		       SKB_GSO_TCP_ECN |
1199		       0)))
1200		goto out;
1201
1202	if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
1203		goto out;
1204
1205	iph = ip_hdr(skb);
1206	ihl = iph->ihl * 4;
1207	if (ihl < sizeof(*iph))
1208		goto out;
1209
1210	if (unlikely(!pskb_may_pull(skb, ihl)))
1211		goto out;
1212
1213	__skb_pull(skb, ihl);
1214	skb_reset_transport_header(skb);
1215	iph = ip_hdr(skb);
1216	id = ntohs(iph->id);
1217	proto = iph->protocol & (MAX_INET_PROTOS - 1);
1218	segs = ERR_PTR(-EPROTONOSUPPORT);
1219
1220	rcu_read_lock();
1221	ops = rcu_dereference(inet_protos[proto]);
1222	if (likely(ops && ops->gso_segment))
1223		segs = ops->gso_segment(skb, features);
1224	rcu_read_unlock();
1225
1226	if (!segs || IS_ERR(segs))
1227		goto out;
1228
1229	skb = segs;
1230	do {
1231		iph = ip_hdr(skb);
1232		iph->id = htons(id++);
1233		iph->tot_len = htons(skb->len - skb->mac_len);
1234		iph->check = 0;
1235		iph->check = ip_fast_csum(skb_network_header(skb), iph->ihl);
1236	} while ((skb = skb->next));
1237
1238out:
1239	return segs;
1240}
1241
1242static struct sk_buff **inet_gro_receive(struct sk_buff **head,
1243					 struct sk_buff *skb)
1244{
1245	struct net_protocol *ops;
1246	struct sk_buff **pp = NULL;
1247	struct sk_buff *p;
1248	struct iphdr *iph;
1249	unsigned int hlen;
1250	unsigned int off;
1251	unsigned int id;
1252	int flush = 1;
1253	int proto;
1254
1255	off = skb_gro_offset(skb);
1256	hlen = off + sizeof(*iph);
1257	iph = skb_gro_header_fast(skb, off);
1258	if (skb_gro_header_hard(skb, hlen)) {
1259		iph = skb_gro_header_slow(skb, hlen, off);
1260		if (unlikely(!iph))
1261			goto out;
1262	}
1263
1264	proto = iph->protocol & (MAX_INET_PROTOS - 1);
1265
1266	rcu_read_lock();
1267	ops = rcu_dereference(inet_protos[proto]);
1268	if (!ops || !ops->gro_receive)
1269		goto out_unlock;
1270
1271	if (*(u8 *)iph != 0x45)
1272		goto out_unlock;
1273
1274	if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1275		goto out_unlock;
1276
1277	id = ntohl(*(u32 *)&iph->id);
1278	flush = (u16)((ntohl(*(u32 *)iph) ^ skb_gro_len(skb)) | (id ^ IP_DF));
1279	id >>= 16;
1280
1281	for (p = *head; p; p = p->next) {
1282		struct iphdr *iph2;
1283
1284		if (!NAPI_GRO_CB(p)->same_flow)
1285			continue;
1286
1287		iph2 = ip_hdr(p);
1288
1289		if ((iph->protocol ^ iph2->protocol) |
1290		    (iph->tos ^ iph2->tos) |
1291		    (iph->saddr ^ iph2->saddr) |
1292		    (iph->daddr ^ iph2->daddr)) {
1293			NAPI_GRO_CB(p)->same_flow = 0;
1294			continue;
1295		}
1296
1297		/* All fields must match except length and checksum. */
1298		NAPI_GRO_CB(p)->flush |=
1299			(iph->ttl ^ iph2->ttl) |
1300			((u16)(ntohs(iph2->id) + NAPI_GRO_CB(p)->count) ^ id);
1301
1302		NAPI_GRO_CB(p)->flush |= flush;
1303	}
1304
1305	NAPI_GRO_CB(skb)->flush |= flush;
1306	skb_gro_pull(skb, sizeof(*iph));
1307	skb_set_transport_header(skb, skb_gro_offset(skb));
1308
1309	pp = ops->gro_receive(head, skb);
1310
1311out_unlock:
1312	rcu_read_unlock();
1313
1314out:
1315	NAPI_GRO_CB(skb)->flush |= flush;
1316
1317	return pp;
1318}
1319
1320static int inet_gro_complete(struct sk_buff *skb)
1321{
1322	struct net_protocol *ops;
1323	struct iphdr *iph = ip_hdr(skb);
1324	int proto = iph->protocol & (MAX_INET_PROTOS - 1);
1325	int err = -ENOSYS;
1326	__be16 newlen = htons(skb->len - skb_network_offset(skb));
1327
1328	csum_replace2(&iph->check, iph->tot_len, newlen);
1329	iph->tot_len = newlen;
1330
1331	rcu_read_lock();
1332	ops = rcu_dereference(inet_protos[proto]);
1333	if (WARN_ON(!ops || !ops->gro_complete))
1334		goto out_unlock;
1335
1336	err = ops->gro_complete(skb);
1337
1338out_unlock:
1339	rcu_read_unlock();
1340
1341	return err;
1342}
1343
1344int inet_ctl_sock_create(struct sock **sk, unsigned short family,
1345			 unsigned short type, unsigned char protocol,
1346			 struct net *net)
1347{
1348	struct socket *sock;
1349	int rc = sock_create_kern(family, type, protocol, &sock);
1350
1351	if (rc == 0) {
1352		*sk = sock->sk;
1353		(*sk)->sk_allocation = GFP_ATOMIC;
1354		/*
1355		 * Unhash it so that IP input processing does not even see it,
1356		 * we do not wish this socket to see incoming packets.
1357		 */
1358		(*sk)->sk_prot->unhash(*sk);
1359
1360		sk_change_net(*sk, net);
1361	}
1362	return rc;
1363}
1364
1365EXPORT_SYMBOL_GPL(inet_ctl_sock_create);
1366
1367unsigned long snmp_fold_field(void *mib[], int offt)
1368{
1369	unsigned long res = 0;
1370	int i;
1371
1372	for_each_possible_cpu(i) {
1373		res += *(((unsigned long *) per_cpu_ptr(mib[0], i)) + offt);
1374		res += *(((unsigned long *) per_cpu_ptr(mib[1], i)) + offt);
1375	}
1376	return res;
1377}
1378EXPORT_SYMBOL_GPL(snmp_fold_field);
1379
1380int snmp_mib_init(void *ptr[2], size_t mibsize)
1381{
1382	BUG_ON(ptr == NULL);
1383	ptr[0] = __alloc_percpu(mibsize, __alignof__(unsigned long long));
1384	if (!ptr[0])
1385		goto err0;
1386	ptr[1] = __alloc_percpu(mibsize, __alignof__(unsigned long long));
1387	if (!ptr[1])
1388		goto err1;
1389	return 0;
1390err1:
1391	free_percpu(ptr[0]);
1392	ptr[0] = NULL;
1393err0:
1394	return -ENOMEM;
1395}
1396EXPORT_SYMBOL_GPL(snmp_mib_init);
1397
1398void snmp_mib_free(void *ptr[2])
1399{
1400	BUG_ON(ptr == NULL);
1401	free_percpu(ptr[0]);
1402	free_percpu(ptr[1]);
1403	ptr[0] = ptr[1] = NULL;
1404}
1405EXPORT_SYMBOL_GPL(snmp_mib_free);
1406
1407#ifdef CONFIG_IP_MULTICAST
1408static struct net_protocol igmp_protocol = {
1409	.handler =	igmp_rcv,
1410	.netns_ok =	1,
1411};
1412#endif
1413
1414static struct net_protocol tcp_protocol = {
1415	.handler =	tcp_v4_rcv,
1416	.err_handler =	tcp_v4_err,
1417	.gso_send_check = tcp_v4_gso_send_check,
1418	.gso_segment =	tcp_tso_segment,
1419	.gro_receive =	tcp4_gro_receive,
1420	.gro_complete =	tcp4_gro_complete,
1421	.no_policy =	1,
1422	.netns_ok =	1,
1423};
1424
1425static struct net_protocol udp_protocol = {
1426	.handler =	udp_rcv,
1427	.err_handler =	udp_err,
1428	.no_policy =	1,
1429	.netns_ok =	1,
1430};
1431
1432static struct net_protocol icmp_protocol = {
1433	.handler =	icmp_rcv,
1434	.no_policy =	1,
1435	.netns_ok =	1,
1436};
1437
1438static __net_init int ipv4_mib_init_net(struct net *net)
1439{
1440	if (snmp_mib_init((void **)net->mib.tcp_statistics,
1441			  sizeof(struct tcp_mib)) < 0)
1442		goto err_tcp_mib;
1443	if (snmp_mib_init((void **)net->mib.ip_statistics,
1444			  sizeof(struct ipstats_mib)) < 0)
1445		goto err_ip_mib;
1446	if (snmp_mib_init((void **)net->mib.net_statistics,
1447			  sizeof(struct linux_mib)) < 0)
1448		goto err_net_mib;
1449	if (snmp_mib_init((void **)net->mib.udp_statistics,
1450			  sizeof(struct udp_mib)) < 0)
1451		goto err_udp_mib;
1452	if (snmp_mib_init((void **)net->mib.udplite_statistics,
1453			  sizeof(struct udp_mib)) < 0)
1454		goto err_udplite_mib;
1455	if (snmp_mib_init((void **)net->mib.icmp_statistics,
1456			  sizeof(struct icmp_mib)) < 0)
1457		goto err_icmp_mib;
1458	if (snmp_mib_init((void **)net->mib.icmpmsg_statistics,
1459			  sizeof(struct icmpmsg_mib)) < 0)
1460		goto err_icmpmsg_mib;
1461
1462	tcp_mib_init(net);
1463	return 0;
1464
1465err_icmpmsg_mib:
1466	snmp_mib_free((void **)net->mib.icmp_statistics);
1467err_icmp_mib:
1468	snmp_mib_free((void **)net->mib.udplite_statistics);
1469err_udplite_mib:
1470	snmp_mib_free((void **)net->mib.udp_statistics);
1471err_udp_mib:
1472	snmp_mib_free((void **)net->mib.net_statistics);
1473err_net_mib:
1474	snmp_mib_free((void **)net->mib.ip_statistics);
1475err_ip_mib:
1476	snmp_mib_free((void **)net->mib.tcp_statistics);
1477err_tcp_mib:
1478	return -ENOMEM;
1479}
1480
1481static __net_exit void ipv4_mib_exit_net(struct net *net)
1482{
1483	snmp_mib_free((void **)net->mib.icmpmsg_statistics);
1484	snmp_mib_free((void **)net->mib.icmp_statistics);
1485	snmp_mib_free((void **)net->mib.udplite_statistics);
1486	snmp_mib_free((void **)net->mib.udp_statistics);
1487	snmp_mib_free((void **)net->mib.net_statistics);
1488	snmp_mib_free((void **)net->mib.ip_statistics);
1489	snmp_mib_free((void **)net->mib.tcp_statistics);
1490}
1491
1492static __net_initdata struct pernet_operations ipv4_mib_ops = {
1493	.init = ipv4_mib_init_net,
1494	.exit = ipv4_mib_exit_net,
1495};
1496
1497static int __init init_ipv4_mibs(void)
1498{
1499	return register_pernet_subsys(&ipv4_mib_ops);
1500}
1501
1502static int ipv4_proc_init(void);
1503
1504/*
1505 *	IP protocol layer initialiser
1506 */
1507
1508static struct packet_type ip_packet_type __read_mostly = {
1509	.type = cpu_to_be16(ETH_P_IP),
1510	.func = ip_rcv,
1511	.gso_send_check = inet_gso_send_check,
1512	.gso_segment = inet_gso_segment,
1513	.gro_receive = inet_gro_receive,
1514	.gro_complete = inet_gro_complete,
1515};
1516
1517static int __init inet_init(void)
1518{
1519	struct sk_buff *dummy_skb;
1520	struct inet_protosw *q;
1521	struct list_head *r;
1522	int rc = -EINVAL;
1523
1524	BUILD_BUG_ON(sizeof(struct inet_skb_parm) > sizeof(dummy_skb->cb));
1525
1526	rc = proto_register(&tcp_prot, 1);
1527	if (rc)
1528		goto out;
1529
1530	rc = proto_register(&udp_prot, 1);
1531	if (rc)
1532		goto out_unregister_tcp_proto;
1533
1534	rc = proto_register(&raw_prot, 1);
1535	if (rc)
1536		goto out_unregister_udp_proto;
1537
1538	/*
1539	 *	Tell SOCKET that we are alive...
1540	 */
1541
1542	(void)sock_register(&inet_family_ops);
1543
1544#ifdef CONFIG_SYSCTL
1545	ip_static_sysctl_init();
1546#endif
1547
1548	/*
1549	 *	Add all the base protocols.
1550	 */
1551
1552	if (inet_add_protocol(&icmp_protocol, IPPROTO_ICMP) < 0)
1553		printk(KERN_CRIT "inet_init: Cannot add ICMP protocol\n");
1554	if (inet_add_protocol(&udp_protocol, IPPROTO_UDP) < 0)
1555		printk(KERN_CRIT "inet_init: Cannot add UDP protocol\n");
1556	if (inet_add_protocol(&tcp_protocol, IPPROTO_TCP) < 0)
1557		printk(KERN_CRIT "inet_init: Cannot add TCP protocol\n");
1558#ifdef CONFIG_IP_MULTICAST
1559	if (inet_add_protocol(&igmp_protocol, IPPROTO_IGMP) < 0)
1560		printk(KERN_CRIT "inet_init: Cannot add IGMP protocol\n");
1561#endif
1562
1563	/* Register the socket-side information for inet_create. */
1564	for (r = &inetsw[0]; r < &inetsw[SOCK_MAX]; ++r)
1565		INIT_LIST_HEAD(r);
1566
1567	for (q = inetsw_array; q < &inetsw_array[INETSW_ARRAY_LEN]; ++q)
1568		inet_register_protosw(q);
1569
1570	/*
1571	 *	Set the ARP module up
1572	 */
1573
1574	arp_init();
1575
1576	/*
1577	 *	Set the IP module up
1578	 */
1579
1580	ip_init();
1581
1582	tcp_v4_init();
1583
1584	/* Setup TCP slab cache for open requests. */
1585	tcp_init();
1586
1587	/* Setup UDP memory threshold */
1588	udp_init();
1589
1590	/* Add UDP-Lite (RFC 3828) */
1591	udplite4_register();
1592
1593	/*
1594	 *	Set the ICMP layer up
1595	 */
1596
1597	if (icmp_init() < 0)
1598		panic("Failed to create the ICMP control socket.\n");
1599
1600	/*
1601	 *	Initialise the multicast router
1602	 */
1603#if defined(CONFIG_IP_MROUTE)
1604	if (ip_mr_init())
1605		printk(KERN_CRIT "inet_init: Cannot init ipv4 mroute\n");
1606#endif
1607	/*
1608	 *	Initialise per-cpu ipv4 mibs
1609	 */
1610
1611	if (init_ipv4_mibs())
1612		printk(KERN_CRIT "inet_init: Cannot init ipv4 mibs\n");
1613
1614	ipv4_proc_init();
1615
1616	ipfrag_init();
1617
1618	dev_add_pack(&ip_packet_type);
1619
1620	rc = 0;
1621out:
1622	return rc;
1623out_unregister_udp_proto:
1624	proto_unregister(&udp_prot);
1625out_unregister_tcp_proto:
1626	proto_unregister(&tcp_prot);
1627	goto out;
1628}
1629
1630fs_initcall(inet_init);
1631
1632/* ------------------------------------------------------------------------ */
1633
1634#ifdef CONFIG_PROC_FS
1635static int __init ipv4_proc_init(void)
1636{
1637	int rc = 0;
1638
1639	if (raw_proc_init())
1640		goto out_raw;
1641	if (tcp4_proc_init())
1642		goto out_tcp;
1643	if (udp4_proc_init())
1644		goto out_udp;
1645	if (ip_misc_proc_init())
1646		goto out_misc;
1647out:
1648	return rc;
1649out_misc:
1650	udp4_proc_exit();
1651out_udp:
1652	tcp4_proc_exit();
1653out_tcp:
1654	raw_proc_exit();
1655out_raw:
1656	rc = -ENOMEM;
1657	goto out;
1658}
1659
1660#else /* CONFIG_PROC_FS */
1661static int __init ipv4_proc_init(void)
1662{
1663	return 0;
1664}
1665#endif /* CONFIG_PROC_FS */
1666
1667MODULE_ALIAS_NETPROTO(PF_INET);
1668
1669EXPORT_SYMBOL(inet_accept);
1670EXPORT_SYMBOL(inet_bind);
1671EXPORT_SYMBOL(inet_dgram_connect);
1672EXPORT_SYMBOL(inet_dgram_ops);
1673EXPORT_SYMBOL(inet_getname);
1674EXPORT_SYMBOL(inet_ioctl);
1675EXPORT_SYMBOL(inet_listen);
1676EXPORT_SYMBOL(inet_register_protosw);
1677EXPORT_SYMBOL(inet_release);
1678EXPORT_SYMBOL(inet_sendmsg);
1679EXPORT_SYMBOL(inet_shutdown);
1680EXPORT_SYMBOL(inet_sock_destruct);
1681EXPORT_SYMBOL(inet_stream_connect);
1682EXPORT_SYMBOL(inet_stream_ops);
1683EXPORT_SYMBOL(inet_unregister_protosw);
1684EXPORT_SYMBOL(sysctl_ip_nonlocal_bind);
1685