af_inet.c revision fec5e652e58fa6017b2c9e06466cb2a6538de5b4
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#include <linux/slab.h>
90
91#include <asm/uaccess.h>
92#include <asm/system.h>
93
94#include <linux/inet.h>
95#include <linux/igmp.h>
96#include <linux/inetdevice.h>
97#include <linux/netdevice.h>
98#include <net/checksum.h>
99#include <net/ip.h>
100#include <net/protocol.h>
101#include <net/arp.h>
102#include <net/route.h>
103#include <net/ip_fib.h>
104#include <net/inet_connection_sock.h>
105#include <net/tcp.h>
106#include <net/udp.h>
107#include <net/udplite.h>
108#include <linux/skbuff.h>
109#include <net/sock.h>
110#include <net/raw.h>
111#include <net/icmp.h>
112#include <net/ipip.h>
113#include <net/inet_common.h>
114#include <net/xfrm.h>
115#include <net/net_namespace.h>
116#ifdef CONFIG_IP_MROUTE
117#include <linux/mroute.h>
118#endif
119
120
121/* The inetsw table contains everything that inet_create needs to
122 * build a new socket.
123 */
124static struct list_head inetsw[SOCK_MAX];
125static DEFINE_SPINLOCK(inetsw_lock);
126
127struct ipv4_config ipv4_config;
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		pr_err("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		pr_err("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(rcu_dereference_check(sk->sk_dst_cache, 1));
158	sk_refcnt_debug_dec(sk);
159}
160EXPORT_SYMBOL(inet_sock_destruct);
161
162/*
163 *	The routines beyond this point handle the behaviour of an AF_INET
164 *	socket object. Mostly it punts to the subprotocols of IP to do
165 *	the work.
166 */
167
168/*
169 *	Automatically bind an unbound socket.
170 */
171
172static int inet_autobind(struct sock *sk)
173{
174	struct inet_sock *inet;
175	/* We may need to bind the socket. */
176	lock_sock(sk);
177	inet = inet_sk(sk);
178	if (!inet->inet_num) {
179		if (sk->sk_prot->get_port(sk, 0)) {
180			release_sock(sk);
181			return -EAGAIN;
182		}
183		inet->inet_sport = htons(inet->inet_num);
184	}
185	release_sock(sk);
186	return 0;
187}
188
189/*
190 *	Move a socket into listening state.
191 */
192int inet_listen(struct socket *sock, int backlog)
193{
194	struct sock *sk = sock->sk;
195	unsigned char old_state;
196	int err;
197
198	lock_sock(sk);
199
200	err = -EINVAL;
201	if (sock->state != SS_UNCONNECTED || sock->type != SOCK_STREAM)
202		goto out;
203
204	old_state = sk->sk_state;
205	if (!((1 << old_state) & (TCPF_CLOSE | TCPF_LISTEN)))
206		goto out;
207
208	/* Really, if the socket is already in listen state
209	 * we can only allow the backlog to be adjusted.
210	 */
211	if (old_state != TCP_LISTEN) {
212		err = inet_csk_listen_start(sk, backlog);
213		if (err)
214			goto out;
215	}
216	sk->sk_max_ack_backlog = backlog;
217	err = 0;
218
219out:
220	release_sock(sk);
221	return err;
222}
223EXPORT_SYMBOL(inet_listen);
224
225u32 inet_ehash_secret __read_mostly;
226EXPORT_SYMBOL(inet_ehash_secret);
227
228/*
229 * inet_ehash_secret must be set exactly once
230 * Instead of using a dedicated spinlock, we (ab)use inetsw_lock
231 */
232void build_ehash_secret(void)
233{
234	u32 rnd;
235	do {
236		get_random_bytes(&rnd, sizeof(rnd));
237	} while (rnd == 0);
238	spin_lock_bh(&inetsw_lock);
239	if (!inet_ehash_secret)
240		inet_ehash_secret = rnd;
241	spin_unlock_bh(&inetsw_lock);
242}
243EXPORT_SYMBOL(build_ehash_secret);
244
245static inline int inet_netns_ok(struct net *net, int protocol)
246{
247	int hash;
248	const struct net_protocol *ipprot;
249
250	if (net_eq(net, &init_net))
251		return 1;
252
253	hash = protocol & (MAX_INET_PROTOS - 1);
254	ipprot = rcu_dereference(inet_protos[hash]);
255
256	if (ipprot == NULL)
257		/* raw IP is OK */
258		return 1;
259	return ipprot->netns_ok;
260}
261
262/*
263 *	Create an inet socket.
264 */
265
266static int inet_create(struct net *net, struct socket *sock, int protocol,
267		       int kern)
268{
269	struct sock *sk;
270	struct inet_protosw *answer;
271	struct inet_sock *inet;
272	struct proto *answer_prot;
273	unsigned char answer_flags;
274	char answer_no_check;
275	int try_loading_module = 0;
276	int err;
277
278	if (unlikely(!inet_ehash_secret))
279		if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM)
280			build_ehash_secret();
281
282	sock->state = SS_UNCONNECTED;
283
284	/* Look for the requested type/protocol pair. */
285lookup_protocol:
286	err = -ESOCKTNOSUPPORT;
287	rcu_read_lock();
288	list_for_each_entry_rcu(answer, &inetsw[sock->type], list) {
289
290		err = 0;
291		/* Check the non-wild match. */
292		if (protocol == answer->protocol) {
293			if (protocol != IPPROTO_IP)
294				break;
295		} else {
296			/* Check for the two wild cases. */
297			if (IPPROTO_IP == protocol) {
298				protocol = answer->protocol;
299				break;
300			}
301			if (IPPROTO_IP == answer->protocol)
302				break;
303		}
304		err = -EPROTONOSUPPORT;
305	}
306
307	if (unlikely(err)) {
308		if (try_loading_module < 2) {
309			rcu_read_unlock();
310			/*
311			 * Be more specific, e.g. net-pf-2-proto-132-type-1
312			 * (net-pf-PF_INET-proto-IPPROTO_SCTP-type-SOCK_STREAM)
313			 */
314			if (++try_loading_module == 1)
315				request_module("net-pf-%d-proto-%d-type-%d",
316					       PF_INET, protocol, sock->type);
317			/*
318			 * Fall back to generic, e.g. net-pf-2-proto-132
319			 * (net-pf-PF_INET-proto-IPPROTO_SCTP)
320			 */
321			else
322				request_module("net-pf-%d-proto-%d",
323					       PF_INET, protocol);
324			goto lookup_protocol;
325		} else
326			goto out_rcu_unlock;
327	}
328
329	err = -EPERM;
330	if (sock->type == SOCK_RAW && !kern && !capable(CAP_NET_RAW))
331		goto out_rcu_unlock;
332
333	err = -EAFNOSUPPORT;
334	if (!inet_netns_ok(net, protocol))
335		goto out_rcu_unlock;
336
337	sock->ops = answer->ops;
338	answer_prot = answer->prot;
339	answer_no_check = answer->no_check;
340	answer_flags = answer->flags;
341	rcu_read_unlock();
342
343	WARN_ON(answer_prot->slab == NULL);
344
345	err = -ENOBUFS;
346	sk = sk_alloc(net, PF_INET, GFP_KERNEL, answer_prot);
347	if (sk == NULL)
348		goto out;
349
350	err = 0;
351	sk->sk_no_check = answer_no_check;
352	if (INET_PROTOSW_REUSE & answer_flags)
353		sk->sk_reuse = 1;
354
355	inet = inet_sk(sk);
356	inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
357
358	if (SOCK_RAW == sock->type) {
359		inet->inet_num = protocol;
360		if (IPPROTO_RAW == protocol)
361			inet->hdrincl = 1;
362	}
363
364	if (ipv4_config.no_pmtu_disc)
365		inet->pmtudisc = IP_PMTUDISC_DONT;
366	else
367		inet->pmtudisc = IP_PMTUDISC_WANT;
368
369	inet->inet_id = 0;
370
371	sock_init_data(sock, sk);
372
373	sk->sk_destruct	   = inet_sock_destruct;
374	sk->sk_protocol	   = protocol;
375	sk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
376
377	inet->uc_ttl	= -1;
378	inet->mc_loop	= 1;
379	inet->mc_ttl	= 1;
380	inet->mc_all	= 1;
381	inet->mc_index	= 0;
382	inet->mc_list	= NULL;
383
384	sk_refcnt_debug_inc(sk);
385
386	if (inet->inet_num) {
387		/* It assumes that any protocol which allows
388		 * the user to assign a number at socket
389		 * creation time automatically
390		 * shares.
391		 */
392		inet->inet_sport = htons(inet->inet_num);
393		/* Add to protocol hash chains. */
394		sk->sk_prot->hash(sk);
395	}
396
397	if (sk->sk_prot->init) {
398		err = sk->sk_prot->init(sk);
399		if (err)
400			sk_common_release(sk);
401	}
402out:
403	return err;
404out_rcu_unlock:
405	rcu_read_unlock();
406	goto out;
407}
408
409
410/*
411 *	The peer socket should always be NULL (or else). When we call this
412 *	function we are destroying the object and from then on nobody
413 *	should refer to it.
414 */
415int inet_release(struct socket *sock)
416{
417	struct sock *sk = sock->sk;
418
419	if (sk) {
420		long timeout;
421
422		inet_rps_reset_flow(sk);
423
424		/* Applications forget to leave groups before exiting */
425		ip_mc_drop_socket(sk);
426
427		/* If linger is set, we don't return until the close
428		 * is complete.  Otherwise we return immediately. The
429		 * actually closing is done the same either way.
430		 *
431		 * If the close is due to the process exiting, we never
432		 * linger..
433		 */
434		timeout = 0;
435		if (sock_flag(sk, SOCK_LINGER) &&
436		    !(current->flags & PF_EXITING))
437			timeout = sk->sk_lingertime;
438		sock->sk = NULL;
439		sk->sk_prot->close(sk, timeout);
440	}
441	return 0;
442}
443EXPORT_SYMBOL(inet_release);
444
445/* It is off by default, see below. */
446int sysctl_ip_nonlocal_bind __read_mostly;
447EXPORT_SYMBOL(sysctl_ip_nonlocal_bind);
448
449int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
450{
451	struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
452	struct sock *sk = sock->sk;
453	struct inet_sock *inet = inet_sk(sk);
454	unsigned short snum;
455	int chk_addr_ret;
456	int err;
457
458	/* If the socket has its own bind function then use it. (RAW) */
459	if (sk->sk_prot->bind) {
460		err = sk->sk_prot->bind(sk, uaddr, addr_len);
461		goto out;
462	}
463	err = -EINVAL;
464	if (addr_len < sizeof(struct sockaddr_in))
465		goto out;
466
467	chk_addr_ret = inet_addr_type(sock_net(sk), addr->sin_addr.s_addr);
468
469	/* Not specified by any standard per-se, however it breaks too
470	 * many applications when removed.  It is unfortunate since
471	 * allowing applications to make a non-local bind solves
472	 * several problems with systems using dynamic addressing.
473	 * (ie. your servers still start up even if your ISDN link
474	 *  is temporarily down)
475	 */
476	err = -EADDRNOTAVAIL;
477	if (!sysctl_ip_nonlocal_bind &&
478	    !(inet->freebind || inet->transparent) &&
479	    addr->sin_addr.s_addr != htonl(INADDR_ANY) &&
480	    chk_addr_ret != RTN_LOCAL &&
481	    chk_addr_ret != RTN_MULTICAST &&
482	    chk_addr_ret != RTN_BROADCAST)
483		goto out;
484
485	snum = ntohs(addr->sin_port);
486	err = -EACCES;
487	if (snum && snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
488		goto out;
489
490	/*      We keep a pair of addresses. rcv_saddr is the one
491	 *      used by hash lookups, and saddr is used for transmit.
492	 *
493	 *      In the BSD API these are the same except where it
494	 *      would be illegal to use them (multicast/broadcast) in
495	 *      which case the sending device address is used.
496	 */
497	lock_sock(sk);
498
499	/* Check these errors (active socket, double bind). */
500	err = -EINVAL;
501	if (sk->sk_state != TCP_CLOSE || inet->inet_num)
502		goto out_release_sock;
503
504	inet->inet_rcv_saddr = inet->inet_saddr = addr->sin_addr.s_addr;
505	if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST)
506		inet->inet_saddr = 0;  /* Use device */
507
508	/* Make sure we are allowed to bind here. */
509	if (sk->sk_prot->get_port(sk, snum)) {
510		inet->inet_saddr = inet->inet_rcv_saddr = 0;
511		err = -EADDRINUSE;
512		goto out_release_sock;
513	}
514
515	if (inet->inet_rcv_saddr)
516		sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
517	if (snum)
518		sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
519	inet->inet_sport = htons(inet->inet_num);
520	inet->inet_daddr = 0;
521	inet->inet_dport = 0;
522	sk_dst_reset(sk);
523	err = 0;
524out_release_sock:
525	release_sock(sk);
526out:
527	return err;
528}
529EXPORT_SYMBOL(inet_bind);
530
531int inet_dgram_connect(struct socket *sock, struct sockaddr * uaddr,
532		       int addr_len, int flags)
533{
534	struct sock *sk = sock->sk;
535
536	if (addr_len < sizeof(uaddr->sa_family))
537		return -EINVAL;
538	if (uaddr->sa_family == AF_UNSPEC)
539		return sk->sk_prot->disconnect(sk, flags);
540
541	if (!inet_sk(sk)->inet_num && inet_autobind(sk))
542		return -EAGAIN;
543	return sk->sk_prot->connect(sk, (struct sockaddr *)uaddr, addr_len);
544}
545EXPORT_SYMBOL(inet_dgram_connect);
546
547static long inet_wait_for_connect(struct sock *sk, long timeo)
548{
549	DEFINE_WAIT(wait);
550
551	prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
552
553	/* Basic assumption: if someone sets sk->sk_err, he _must_
554	 * change state of the socket from TCP_SYN_*.
555	 * Connect() does not allow to get error notifications
556	 * without closing the socket.
557	 */
558	while ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
559		release_sock(sk);
560		timeo = schedule_timeout(timeo);
561		lock_sock(sk);
562		if (signal_pending(current) || !timeo)
563			break;
564		prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
565	}
566	finish_wait(sk->sk_sleep, &wait);
567	return timeo;
568}
569
570/*
571 *	Connect to a remote host. There is regrettably still a little
572 *	TCP 'magic' in here.
573 */
574int inet_stream_connect(struct socket *sock, struct sockaddr *uaddr,
575			int addr_len, int flags)
576{
577	struct sock *sk = sock->sk;
578	int err;
579	long timeo;
580
581	if (addr_len < sizeof(uaddr->sa_family))
582		return -EINVAL;
583
584	lock_sock(sk);
585
586	if (uaddr->sa_family == AF_UNSPEC) {
587		err = sk->sk_prot->disconnect(sk, flags);
588		sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
589		goto out;
590	}
591
592	switch (sock->state) {
593	default:
594		err = -EINVAL;
595		goto out;
596	case SS_CONNECTED:
597		err = -EISCONN;
598		goto out;
599	case SS_CONNECTING:
600		err = -EALREADY;
601		/* Fall out of switch with err, set for this state */
602		break;
603	case SS_UNCONNECTED:
604		err = -EISCONN;
605		if (sk->sk_state != TCP_CLOSE)
606			goto out;
607
608		err = sk->sk_prot->connect(sk, uaddr, addr_len);
609		if (err < 0)
610			goto out;
611
612		sock->state = SS_CONNECTING;
613
614		/* Just entered SS_CONNECTING state; the only
615		 * difference is that return value in non-blocking
616		 * case is EINPROGRESS, rather than EALREADY.
617		 */
618		err = -EINPROGRESS;
619		break;
620	}
621
622	timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
623
624	if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
625		/* Error code is set above */
626		if (!timeo || !inet_wait_for_connect(sk, timeo))
627			goto out;
628
629		err = sock_intr_errno(timeo);
630		if (signal_pending(current))
631			goto out;
632	}
633
634	/* Connection was closed by RST, timeout, ICMP error
635	 * or another process disconnected us.
636	 */
637	if (sk->sk_state == TCP_CLOSE)
638		goto sock_error;
639
640	/* sk->sk_err may be not zero now, if RECVERR was ordered by user
641	 * and error was received after socket entered established state.
642	 * Hence, it is handled normally after connect() return successfully.
643	 */
644
645	sock->state = SS_CONNECTED;
646	err = 0;
647out:
648	release_sock(sk);
649	return err;
650
651sock_error:
652	err = sock_error(sk) ? : -ECONNABORTED;
653	sock->state = SS_UNCONNECTED;
654	if (sk->sk_prot->disconnect(sk, flags))
655		sock->state = SS_DISCONNECTING;
656	goto out;
657}
658EXPORT_SYMBOL(inet_stream_connect);
659
660/*
661 *	Accept a pending connection. The TCP layer now gives BSD semantics.
662 */
663
664int inet_accept(struct socket *sock, struct socket *newsock, int flags)
665{
666	struct sock *sk1 = sock->sk;
667	int err = -EINVAL;
668	struct sock *sk2 = sk1->sk_prot->accept(sk1, flags, &err);
669
670	if (!sk2)
671		goto do_err;
672
673	lock_sock(sk2);
674
675	WARN_ON(!((1 << sk2->sk_state) &
676		  (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT | TCPF_CLOSE)));
677
678	sock_graft(sk2, newsock);
679
680	newsock->state = SS_CONNECTED;
681	err = 0;
682	release_sock(sk2);
683do_err:
684	return err;
685}
686EXPORT_SYMBOL(inet_accept);
687
688
689/*
690 *	This does both peername and sockname.
691 */
692int inet_getname(struct socket *sock, struct sockaddr *uaddr,
693			int *uaddr_len, int peer)
694{
695	struct sock *sk		= sock->sk;
696	struct inet_sock *inet	= inet_sk(sk);
697	DECLARE_SOCKADDR(struct sockaddr_in *, sin, uaddr);
698
699	sin->sin_family = AF_INET;
700	if (peer) {
701		if (!inet->inet_dport ||
702		    (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
703		     peer == 1))
704			return -ENOTCONN;
705		sin->sin_port = inet->inet_dport;
706		sin->sin_addr.s_addr = inet->inet_daddr;
707	} else {
708		__be32 addr = inet->inet_rcv_saddr;
709		if (!addr)
710			addr = inet->inet_saddr;
711		sin->sin_port = inet->inet_sport;
712		sin->sin_addr.s_addr = addr;
713	}
714	memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
715	*uaddr_len = sizeof(*sin);
716	return 0;
717}
718EXPORT_SYMBOL(inet_getname);
719
720int inet_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
721		 size_t size)
722{
723	struct sock *sk = sock->sk;
724
725	inet_rps_record_flow(sk);
726
727	/* We may need to bind the socket. */
728	if (!inet_sk(sk)->inet_num && inet_autobind(sk))
729		return -EAGAIN;
730
731	return sk->sk_prot->sendmsg(iocb, sk, msg, size);
732}
733EXPORT_SYMBOL(inet_sendmsg);
734
735static ssize_t inet_sendpage(struct socket *sock, struct page *page, int offset,
736			     size_t size, int flags)
737{
738	struct sock *sk = sock->sk;
739
740	inet_rps_record_flow(sk);
741
742	/* We may need to bind the socket. */
743	if (!inet_sk(sk)->inet_num && inet_autobind(sk))
744		return -EAGAIN;
745
746	if (sk->sk_prot->sendpage)
747		return sk->sk_prot->sendpage(sk, page, offset, size, flags);
748	return sock_no_sendpage(sock, page, offset, size, flags);
749}
750
751int inet_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
752		 size_t size, int flags)
753{
754	struct sock *sk = sock->sk;
755	int addr_len = 0;
756	int err;
757
758	inet_rps_record_flow(sk);
759
760	err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT,
761				   flags & ~MSG_DONTWAIT, &addr_len);
762	if (err >= 0)
763		msg->msg_namelen = addr_len;
764	return err;
765}
766EXPORT_SYMBOL(inet_recvmsg);
767
768int inet_shutdown(struct socket *sock, int how)
769{
770	struct sock *sk = sock->sk;
771	int err = 0;
772
773	/* This should really check to make sure
774	 * the socket is a TCP socket. (WHY AC...)
775	 */
776	how++; /* maps 0->1 has the advantage of making bit 1 rcvs and
777		       1->2 bit 2 snds.
778		       2->3 */
779	if ((how & ~SHUTDOWN_MASK) || !how)	/* MAXINT->0 */
780		return -EINVAL;
781
782	lock_sock(sk);
783	if (sock->state == SS_CONNECTING) {
784		if ((1 << sk->sk_state) &
785		    (TCPF_SYN_SENT | TCPF_SYN_RECV | TCPF_CLOSE))
786			sock->state = SS_DISCONNECTING;
787		else
788			sock->state = SS_CONNECTED;
789	}
790
791	switch (sk->sk_state) {
792	case TCP_CLOSE:
793		err = -ENOTCONN;
794		/* Hack to wake up other listeners, who can poll for
795		   POLLHUP, even on eg. unconnected UDP sockets -- RR */
796	default:
797		sk->sk_shutdown |= how;
798		if (sk->sk_prot->shutdown)
799			sk->sk_prot->shutdown(sk, how);
800		break;
801
802	/* Remaining two branches are temporary solution for missing
803	 * close() in multithreaded environment. It is _not_ a good idea,
804	 * but we have no choice until close() is repaired at VFS level.
805	 */
806	case TCP_LISTEN:
807		if (!(how & RCV_SHUTDOWN))
808			break;
809		/* Fall through */
810	case TCP_SYN_SENT:
811		err = sk->sk_prot->disconnect(sk, O_NONBLOCK);
812		sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
813		break;
814	}
815
816	/* Wake up anyone sleeping in poll. */
817	sk->sk_state_change(sk);
818	release_sock(sk);
819	return err;
820}
821EXPORT_SYMBOL(inet_shutdown);
822
823/*
824 *	ioctl() calls you can issue on an INET socket. Most of these are
825 *	device configuration and stuff and very rarely used. Some ioctls
826 *	pass on to the socket itself.
827 *
828 *	NOTE: I like the idea of a module for the config stuff. ie ifconfig
829 *	loads the devconfigure module does its configuring and unloads it.
830 *	There's a good 20K of config code hanging around the kernel.
831 */
832
833int inet_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
834{
835	struct sock *sk = sock->sk;
836	int err = 0;
837	struct net *net = sock_net(sk);
838
839	switch (cmd) {
840	case SIOCGSTAMP:
841		err = sock_get_timestamp(sk, (struct timeval __user *)arg);
842		break;
843	case SIOCGSTAMPNS:
844		err = sock_get_timestampns(sk, (struct timespec __user *)arg);
845		break;
846	case SIOCADDRT:
847	case SIOCDELRT:
848	case SIOCRTMSG:
849		err = ip_rt_ioctl(net, cmd, (void __user *)arg);
850		break;
851	case SIOCDARP:
852	case SIOCGARP:
853	case SIOCSARP:
854		err = arp_ioctl(net, cmd, (void __user *)arg);
855		break;
856	case SIOCGIFADDR:
857	case SIOCSIFADDR:
858	case SIOCGIFBRDADDR:
859	case SIOCSIFBRDADDR:
860	case SIOCGIFNETMASK:
861	case SIOCSIFNETMASK:
862	case SIOCGIFDSTADDR:
863	case SIOCSIFDSTADDR:
864	case SIOCSIFPFLAGS:
865	case SIOCGIFPFLAGS:
866	case SIOCSIFFLAGS:
867		err = devinet_ioctl(net, cmd, (void __user *)arg);
868		break;
869	default:
870		if (sk->sk_prot->ioctl)
871			err = sk->sk_prot->ioctl(sk, cmd, arg);
872		else
873			err = -ENOIOCTLCMD;
874		break;
875	}
876	return err;
877}
878EXPORT_SYMBOL(inet_ioctl);
879
880const struct proto_ops inet_stream_ops = {
881	.family		   = PF_INET,
882	.owner		   = THIS_MODULE,
883	.release	   = inet_release,
884	.bind		   = inet_bind,
885	.connect	   = inet_stream_connect,
886	.socketpair	   = sock_no_socketpair,
887	.accept		   = inet_accept,
888	.getname	   = inet_getname,
889	.poll		   = tcp_poll,
890	.ioctl		   = inet_ioctl,
891	.listen		   = inet_listen,
892	.shutdown	   = inet_shutdown,
893	.setsockopt	   = sock_common_setsockopt,
894	.getsockopt	   = sock_common_getsockopt,
895	.sendmsg	   = tcp_sendmsg,
896	.recvmsg	   = inet_recvmsg,
897	.mmap		   = sock_no_mmap,
898	.sendpage	   = tcp_sendpage,
899	.splice_read	   = tcp_splice_read,
900#ifdef CONFIG_COMPAT
901	.compat_setsockopt = compat_sock_common_setsockopt,
902	.compat_getsockopt = compat_sock_common_getsockopt,
903#endif
904};
905EXPORT_SYMBOL(inet_stream_ops);
906
907const struct proto_ops inet_dgram_ops = {
908	.family		   = PF_INET,
909	.owner		   = THIS_MODULE,
910	.release	   = inet_release,
911	.bind		   = inet_bind,
912	.connect	   = inet_dgram_connect,
913	.socketpair	   = sock_no_socketpair,
914	.accept		   = sock_no_accept,
915	.getname	   = inet_getname,
916	.poll		   = udp_poll,
917	.ioctl		   = inet_ioctl,
918	.listen		   = sock_no_listen,
919	.shutdown	   = inet_shutdown,
920	.setsockopt	   = sock_common_setsockopt,
921	.getsockopt	   = sock_common_getsockopt,
922	.sendmsg	   = inet_sendmsg,
923	.recvmsg	   = inet_recvmsg,
924	.mmap		   = sock_no_mmap,
925	.sendpage	   = inet_sendpage,
926#ifdef CONFIG_COMPAT
927	.compat_setsockopt = compat_sock_common_setsockopt,
928	.compat_getsockopt = compat_sock_common_getsockopt,
929#endif
930};
931EXPORT_SYMBOL(inet_dgram_ops);
932
933/*
934 * For SOCK_RAW sockets; should be the same as inet_dgram_ops but without
935 * udp_poll
936 */
937static const struct proto_ops inet_sockraw_ops = {
938	.family		   = PF_INET,
939	.owner		   = THIS_MODULE,
940	.release	   = inet_release,
941	.bind		   = inet_bind,
942	.connect	   = inet_dgram_connect,
943	.socketpair	   = sock_no_socketpair,
944	.accept		   = sock_no_accept,
945	.getname	   = inet_getname,
946	.poll		   = datagram_poll,
947	.ioctl		   = inet_ioctl,
948	.listen		   = sock_no_listen,
949	.shutdown	   = inet_shutdown,
950	.setsockopt	   = sock_common_setsockopt,
951	.getsockopt	   = sock_common_getsockopt,
952	.sendmsg	   = inet_sendmsg,
953	.recvmsg	   = inet_recvmsg,
954	.mmap		   = sock_no_mmap,
955	.sendpage	   = inet_sendpage,
956#ifdef CONFIG_COMPAT
957	.compat_setsockopt = compat_sock_common_setsockopt,
958	.compat_getsockopt = compat_sock_common_getsockopt,
959#endif
960};
961
962static const struct net_proto_family inet_family_ops = {
963	.family = PF_INET,
964	.create = inet_create,
965	.owner	= THIS_MODULE,
966};
967
968/* Upon startup we insert all the elements in inetsw_array[] into
969 * the linked list inetsw.
970 */
971static struct inet_protosw inetsw_array[] =
972{
973	{
974		.type =       SOCK_STREAM,
975		.protocol =   IPPROTO_TCP,
976		.prot =       &tcp_prot,
977		.ops =        &inet_stream_ops,
978		.no_check =   0,
979		.flags =      INET_PROTOSW_PERMANENT |
980			      INET_PROTOSW_ICSK,
981	},
982
983	{
984		.type =       SOCK_DGRAM,
985		.protocol =   IPPROTO_UDP,
986		.prot =       &udp_prot,
987		.ops =        &inet_dgram_ops,
988		.no_check =   UDP_CSUM_DEFAULT,
989		.flags =      INET_PROTOSW_PERMANENT,
990       },
991
992
993       {
994	       .type =       SOCK_RAW,
995	       .protocol =   IPPROTO_IP,	/* wild card */
996	       .prot =       &raw_prot,
997	       .ops =        &inet_sockraw_ops,
998	       .no_check =   UDP_CSUM_DEFAULT,
999	       .flags =      INET_PROTOSW_REUSE,
1000       }
1001};
1002
1003#define INETSW_ARRAY_LEN ARRAY_SIZE(inetsw_array)
1004
1005void inet_register_protosw(struct inet_protosw *p)
1006{
1007	struct list_head *lh;
1008	struct inet_protosw *answer;
1009	int protocol = p->protocol;
1010	struct list_head *last_perm;
1011
1012	spin_lock_bh(&inetsw_lock);
1013
1014	if (p->type >= SOCK_MAX)
1015		goto out_illegal;
1016
1017	/* If we are trying to override a permanent protocol, bail. */
1018	answer = NULL;
1019	last_perm = &inetsw[p->type];
1020	list_for_each(lh, &inetsw[p->type]) {
1021		answer = list_entry(lh, struct inet_protosw, list);
1022
1023		/* Check only the non-wild match. */
1024		if (INET_PROTOSW_PERMANENT & answer->flags) {
1025			if (protocol == answer->protocol)
1026				break;
1027			last_perm = lh;
1028		}
1029
1030		answer = NULL;
1031	}
1032	if (answer)
1033		goto out_permanent;
1034
1035	/* Add the new entry after the last permanent entry if any, so that
1036	 * the new entry does not override a permanent entry when matched with
1037	 * a wild-card protocol. But it is allowed to override any existing
1038	 * non-permanent entry.  This means that when we remove this entry, the
1039	 * system automatically returns to the old behavior.
1040	 */
1041	list_add_rcu(&p->list, last_perm);
1042out:
1043	spin_unlock_bh(&inetsw_lock);
1044
1045	return;
1046
1047out_permanent:
1048	printk(KERN_ERR "Attempt to override permanent protocol %d.\n",
1049	       protocol);
1050	goto out;
1051
1052out_illegal:
1053	printk(KERN_ERR
1054	       "Ignoring attempt to register invalid socket type %d.\n",
1055	       p->type);
1056	goto out;
1057}
1058EXPORT_SYMBOL(inet_register_protosw);
1059
1060void inet_unregister_protosw(struct inet_protosw *p)
1061{
1062	if (INET_PROTOSW_PERMANENT & p->flags) {
1063		printk(KERN_ERR
1064		       "Attempt to unregister permanent protocol %d.\n",
1065		       p->protocol);
1066	} else {
1067		spin_lock_bh(&inetsw_lock);
1068		list_del_rcu(&p->list);
1069		spin_unlock_bh(&inetsw_lock);
1070
1071		synchronize_net();
1072	}
1073}
1074EXPORT_SYMBOL(inet_unregister_protosw);
1075
1076/*
1077 *      Shall we try to damage output packets if routing dev changes?
1078 */
1079
1080int sysctl_ip_dynaddr __read_mostly;
1081
1082static int inet_sk_reselect_saddr(struct sock *sk)
1083{
1084	struct inet_sock *inet = inet_sk(sk);
1085	int err;
1086	struct rtable *rt;
1087	__be32 old_saddr = inet->inet_saddr;
1088	__be32 new_saddr;
1089	__be32 daddr = inet->inet_daddr;
1090
1091	if (inet->opt && inet->opt->srr)
1092		daddr = inet->opt->faddr;
1093
1094	/* Query new route. */
1095	err = ip_route_connect(&rt, daddr, 0,
1096			       RT_CONN_FLAGS(sk),
1097			       sk->sk_bound_dev_if,
1098			       sk->sk_protocol,
1099			       inet->inet_sport, inet->inet_dport, sk, 0);
1100	if (err)
1101		return err;
1102
1103	sk_setup_caps(sk, &rt->u.dst);
1104
1105	new_saddr = rt->rt_src;
1106
1107	if (new_saddr == old_saddr)
1108		return 0;
1109
1110	if (sysctl_ip_dynaddr > 1) {
1111		printk(KERN_INFO "%s(): shifting inet->saddr from %pI4 to %pI4\n",
1112		       __func__, &old_saddr, &new_saddr);
1113	}
1114
1115	inet->inet_saddr = inet->inet_rcv_saddr = new_saddr;
1116
1117	/*
1118	 * XXX The only one ugly spot where we need to
1119	 * XXX really change the sockets identity after
1120	 * XXX it has entered the hashes. -DaveM
1121	 *
1122	 * Besides that, it does not check for connection
1123	 * uniqueness. Wait for troubles.
1124	 */
1125	__sk_prot_rehash(sk);
1126	return 0;
1127}
1128
1129int inet_sk_rebuild_header(struct sock *sk)
1130{
1131	struct inet_sock *inet = inet_sk(sk);
1132	struct rtable *rt = (struct rtable *)__sk_dst_check(sk, 0);
1133	__be32 daddr;
1134	int err;
1135
1136	/* Route is OK, nothing to do. */
1137	if (rt)
1138		return 0;
1139
1140	/* Reroute. */
1141	daddr = inet->inet_daddr;
1142	if (inet->opt && inet->opt->srr)
1143		daddr = inet->opt->faddr;
1144{
1145	struct flowi fl = {
1146		.oif = sk->sk_bound_dev_if,
1147		.mark = sk->sk_mark,
1148		.nl_u = {
1149			.ip4_u = {
1150				.daddr	= daddr,
1151				.saddr	= inet->inet_saddr,
1152				.tos	= RT_CONN_FLAGS(sk),
1153			},
1154		},
1155		.proto = sk->sk_protocol,
1156		.flags = inet_sk_flowi_flags(sk),
1157		.uli_u = {
1158			.ports = {
1159				.sport = inet->inet_sport,
1160				.dport = inet->inet_dport,
1161			},
1162		},
1163	};
1164
1165	security_sk_classify_flow(sk, &fl);
1166	err = ip_route_output_flow(sock_net(sk), &rt, &fl, sk, 0);
1167}
1168	if (!err)
1169		sk_setup_caps(sk, &rt->u.dst);
1170	else {
1171		/* Routing failed... */
1172		sk->sk_route_caps = 0;
1173		/*
1174		 * Other protocols have to map its equivalent state to TCP_SYN_SENT.
1175		 * DCCP maps its DCCP_REQUESTING state to TCP_SYN_SENT. -acme
1176		 */
1177		if (!sysctl_ip_dynaddr ||
1178		    sk->sk_state != TCP_SYN_SENT ||
1179		    (sk->sk_userlocks & SOCK_BINDADDR_LOCK) ||
1180		    (err = inet_sk_reselect_saddr(sk)) != 0)
1181			sk->sk_err_soft = -err;
1182	}
1183
1184	return err;
1185}
1186EXPORT_SYMBOL(inet_sk_rebuild_header);
1187
1188static int inet_gso_send_check(struct sk_buff *skb)
1189{
1190	struct iphdr *iph;
1191	const struct net_protocol *ops;
1192	int proto;
1193	int ihl;
1194	int err = -EINVAL;
1195
1196	if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
1197		goto out;
1198
1199	iph = ip_hdr(skb);
1200	ihl = iph->ihl * 4;
1201	if (ihl < sizeof(*iph))
1202		goto out;
1203
1204	if (unlikely(!pskb_may_pull(skb, ihl)))
1205		goto out;
1206
1207	__skb_pull(skb, ihl);
1208	skb_reset_transport_header(skb);
1209	iph = ip_hdr(skb);
1210	proto = iph->protocol & (MAX_INET_PROTOS - 1);
1211	err = -EPROTONOSUPPORT;
1212
1213	rcu_read_lock();
1214	ops = rcu_dereference(inet_protos[proto]);
1215	if (likely(ops && ops->gso_send_check))
1216		err = ops->gso_send_check(skb);
1217	rcu_read_unlock();
1218
1219out:
1220	return err;
1221}
1222
1223static struct sk_buff *inet_gso_segment(struct sk_buff *skb, int features)
1224{
1225	struct sk_buff *segs = ERR_PTR(-EINVAL);
1226	struct iphdr *iph;
1227	const struct net_protocol *ops;
1228	int proto;
1229	int ihl;
1230	int id;
1231	unsigned int offset = 0;
1232
1233	if (!(features & NETIF_F_V4_CSUM))
1234		features &= ~NETIF_F_SG;
1235
1236	if (unlikely(skb_shinfo(skb)->gso_type &
1237		     ~(SKB_GSO_TCPV4 |
1238		       SKB_GSO_UDP |
1239		       SKB_GSO_DODGY |
1240		       SKB_GSO_TCP_ECN |
1241		       0)))
1242		goto out;
1243
1244	if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
1245		goto out;
1246
1247	iph = ip_hdr(skb);
1248	ihl = iph->ihl * 4;
1249	if (ihl < sizeof(*iph))
1250		goto out;
1251
1252	if (unlikely(!pskb_may_pull(skb, ihl)))
1253		goto out;
1254
1255	__skb_pull(skb, ihl);
1256	skb_reset_transport_header(skb);
1257	iph = ip_hdr(skb);
1258	id = ntohs(iph->id);
1259	proto = iph->protocol & (MAX_INET_PROTOS - 1);
1260	segs = ERR_PTR(-EPROTONOSUPPORT);
1261
1262	rcu_read_lock();
1263	ops = rcu_dereference(inet_protos[proto]);
1264	if (likely(ops && ops->gso_segment))
1265		segs = ops->gso_segment(skb, features);
1266	rcu_read_unlock();
1267
1268	if (!segs || IS_ERR(segs))
1269		goto out;
1270
1271	skb = segs;
1272	do {
1273		iph = ip_hdr(skb);
1274		if (proto == IPPROTO_UDP) {
1275			iph->id = htons(id);
1276			iph->frag_off = htons(offset >> 3);
1277			if (skb->next != NULL)
1278				iph->frag_off |= htons(IP_MF);
1279			offset += (skb->len - skb->mac_len - iph->ihl * 4);
1280		} else
1281			iph->id = htons(id++);
1282		iph->tot_len = htons(skb->len - skb->mac_len);
1283		iph->check = 0;
1284		iph->check = ip_fast_csum(skb_network_header(skb), iph->ihl);
1285	} while ((skb = skb->next));
1286
1287out:
1288	return segs;
1289}
1290
1291static struct sk_buff **inet_gro_receive(struct sk_buff **head,
1292					 struct sk_buff *skb)
1293{
1294	const struct net_protocol *ops;
1295	struct sk_buff **pp = NULL;
1296	struct sk_buff *p;
1297	struct iphdr *iph;
1298	unsigned int hlen;
1299	unsigned int off;
1300	unsigned int id;
1301	int flush = 1;
1302	int proto;
1303
1304	off = skb_gro_offset(skb);
1305	hlen = off + sizeof(*iph);
1306	iph = skb_gro_header_fast(skb, off);
1307	if (skb_gro_header_hard(skb, hlen)) {
1308		iph = skb_gro_header_slow(skb, hlen, off);
1309		if (unlikely(!iph))
1310			goto out;
1311	}
1312
1313	proto = iph->protocol & (MAX_INET_PROTOS - 1);
1314
1315	rcu_read_lock();
1316	ops = rcu_dereference(inet_protos[proto]);
1317	if (!ops || !ops->gro_receive)
1318		goto out_unlock;
1319
1320	if (*(u8 *)iph != 0x45)
1321		goto out_unlock;
1322
1323	if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1324		goto out_unlock;
1325
1326	id = ntohl(*(u32 *)&iph->id);
1327	flush = (u16)((ntohl(*(u32 *)iph) ^ skb_gro_len(skb)) | (id ^ IP_DF));
1328	id >>= 16;
1329
1330	for (p = *head; p; p = p->next) {
1331		struct iphdr *iph2;
1332
1333		if (!NAPI_GRO_CB(p)->same_flow)
1334			continue;
1335
1336		iph2 = ip_hdr(p);
1337
1338		if ((iph->protocol ^ iph2->protocol) |
1339		    (iph->tos ^ iph2->tos) |
1340		    (iph->saddr ^ iph2->saddr) |
1341		    (iph->daddr ^ iph2->daddr)) {
1342			NAPI_GRO_CB(p)->same_flow = 0;
1343			continue;
1344		}
1345
1346		/* All fields must match except length and checksum. */
1347		NAPI_GRO_CB(p)->flush |=
1348			(iph->ttl ^ iph2->ttl) |
1349			((u16)(ntohs(iph2->id) + NAPI_GRO_CB(p)->count) ^ id);
1350
1351		NAPI_GRO_CB(p)->flush |= flush;
1352	}
1353
1354	NAPI_GRO_CB(skb)->flush |= flush;
1355	skb_gro_pull(skb, sizeof(*iph));
1356	skb_set_transport_header(skb, skb_gro_offset(skb));
1357
1358	pp = ops->gro_receive(head, skb);
1359
1360out_unlock:
1361	rcu_read_unlock();
1362
1363out:
1364	NAPI_GRO_CB(skb)->flush |= flush;
1365
1366	return pp;
1367}
1368
1369static int inet_gro_complete(struct sk_buff *skb)
1370{
1371	const struct net_protocol *ops;
1372	struct iphdr *iph = ip_hdr(skb);
1373	int proto = iph->protocol & (MAX_INET_PROTOS - 1);
1374	int err = -ENOSYS;
1375	__be16 newlen = htons(skb->len - skb_network_offset(skb));
1376
1377	csum_replace2(&iph->check, iph->tot_len, newlen);
1378	iph->tot_len = newlen;
1379
1380	rcu_read_lock();
1381	ops = rcu_dereference(inet_protos[proto]);
1382	if (WARN_ON(!ops || !ops->gro_complete))
1383		goto out_unlock;
1384
1385	err = ops->gro_complete(skb);
1386
1387out_unlock:
1388	rcu_read_unlock();
1389
1390	return err;
1391}
1392
1393int inet_ctl_sock_create(struct sock **sk, unsigned short family,
1394			 unsigned short type, unsigned char protocol,
1395			 struct net *net)
1396{
1397	struct socket *sock;
1398	int rc = sock_create_kern(family, type, protocol, &sock);
1399
1400	if (rc == 0) {
1401		*sk = sock->sk;
1402		(*sk)->sk_allocation = GFP_ATOMIC;
1403		/*
1404		 * Unhash it so that IP input processing does not even see it,
1405		 * we do not wish this socket to see incoming packets.
1406		 */
1407		(*sk)->sk_prot->unhash(*sk);
1408
1409		sk_change_net(*sk, net);
1410	}
1411	return rc;
1412}
1413EXPORT_SYMBOL_GPL(inet_ctl_sock_create);
1414
1415unsigned long snmp_fold_field(void __percpu *mib[], int offt)
1416{
1417	unsigned long res = 0;
1418	int i;
1419
1420	for_each_possible_cpu(i) {
1421		res += *(((unsigned long *) per_cpu_ptr(mib[0], i)) + offt);
1422		res += *(((unsigned long *) per_cpu_ptr(mib[1], i)) + offt);
1423	}
1424	return res;
1425}
1426EXPORT_SYMBOL_GPL(snmp_fold_field);
1427
1428int snmp_mib_init(void __percpu *ptr[2], size_t mibsize)
1429{
1430	BUG_ON(ptr == NULL);
1431	ptr[0] = __alloc_percpu(mibsize, __alignof__(unsigned long));
1432	if (!ptr[0])
1433		goto err0;
1434	ptr[1] = __alloc_percpu(mibsize, __alignof__(unsigned long));
1435	if (!ptr[1])
1436		goto err1;
1437	return 0;
1438err1:
1439	free_percpu(ptr[0]);
1440	ptr[0] = NULL;
1441err0:
1442	return -ENOMEM;
1443}
1444EXPORT_SYMBOL_GPL(snmp_mib_init);
1445
1446void snmp_mib_free(void __percpu *ptr[2])
1447{
1448	BUG_ON(ptr == NULL);
1449	free_percpu(ptr[0]);
1450	free_percpu(ptr[1]);
1451	ptr[0] = ptr[1] = NULL;
1452}
1453EXPORT_SYMBOL_GPL(snmp_mib_free);
1454
1455#ifdef CONFIG_IP_MULTICAST
1456static const struct net_protocol igmp_protocol = {
1457	.handler =	igmp_rcv,
1458	.netns_ok =	1,
1459};
1460#endif
1461
1462static const struct net_protocol tcp_protocol = {
1463	.handler =	tcp_v4_rcv,
1464	.err_handler =	tcp_v4_err,
1465	.gso_send_check = tcp_v4_gso_send_check,
1466	.gso_segment =	tcp_tso_segment,
1467	.gro_receive =	tcp4_gro_receive,
1468	.gro_complete =	tcp4_gro_complete,
1469	.no_policy =	1,
1470	.netns_ok =	1,
1471};
1472
1473static const struct net_protocol udp_protocol = {
1474	.handler =	udp_rcv,
1475	.err_handler =	udp_err,
1476	.gso_send_check = udp4_ufo_send_check,
1477	.gso_segment = udp4_ufo_fragment,
1478	.no_policy =	1,
1479	.netns_ok =	1,
1480};
1481
1482static const struct net_protocol icmp_protocol = {
1483	.handler =	icmp_rcv,
1484	.no_policy =	1,
1485	.netns_ok =	1,
1486};
1487
1488static __net_init int ipv4_mib_init_net(struct net *net)
1489{
1490	if (snmp_mib_init((void __percpu **)net->mib.tcp_statistics,
1491			  sizeof(struct tcp_mib)) < 0)
1492		goto err_tcp_mib;
1493	if (snmp_mib_init((void __percpu **)net->mib.ip_statistics,
1494			  sizeof(struct ipstats_mib)) < 0)
1495		goto err_ip_mib;
1496	if (snmp_mib_init((void __percpu **)net->mib.net_statistics,
1497			  sizeof(struct linux_mib)) < 0)
1498		goto err_net_mib;
1499	if (snmp_mib_init((void __percpu **)net->mib.udp_statistics,
1500			  sizeof(struct udp_mib)) < 0)
1501		goto err_udp_mib;
1502	if (snmp_mib_init((void __percpu **)net->mib.udplite_statistics,
1503			  sizeof(struct udp_mib)) < 0)
1504		goto err_udplite_mib;
1505	if (snmp_mib_init((void __percpu **)net->mib.icmp_statistics,
1506			  sizeof(struct icmp_mib)) < 0)
1507		goto err_icmp_mib;
1508	if (snmp_mib_init((void __percpu **)net->mib.icmpmsg_statistics,
1509			  sizeof(struct icmpmsg_mib)) < 0)
1510		goto err_icmpmsg_mib;
1511
1512	tcp_mib_init(net);
1513	return 0;
1514
1515err_icmpmsg_mib:
1516	snmp_mib_free((void __percpu **)net->mib.icmp_statistics);
1517err_icmp_mib:
1518	snmp_mib_free((void __percpu **)net->mib.udplite_statistics);
1519err_udplite_mib:
1520	snmp_mib_free((void __percpu **)net->mib.udp_statistics);
1521err_udp_mib:
1522	snmp_mib_free((void __percpu **)net->mib.net_statistics);
1523err_net_mib:
1524	snmp_mib_free((void __percpu **)net->mib.ip_statistics);
1525err_ip_mib:
1526	snmp_mib_free((void __percpu **)net->mib.tcp_statistics);
1527err_tcp_mib:
1528	return -ENOMEM;
1529}
1530
1531static __net_exit void ipv4_mib_exit_net(struct net *net)
1532{
1533	snmp_mib_free((void __percpu **)net->mib.icmpmsg_statistics);
1534	snmp_mib_free((void __percpu **)net->mib.icmp_statistics);
1535	snmp_mib_free((void __percpu **)net->mib.udplite_statistics);
1536	snmp_mib_free((void __percpu **)net->mib.udp_statistics);
1537	snmp_mib_free((void __percpu **)net->mib.net_statistics);
1538	snmp_mib_free((void __percpu **)net->mib.ip_statistics);
1539	snmp_mib_free((void __percpu **)net->mib.tcp_statistics);
1540}
1541
1542static __net_initdata struct pernet_operations ipv4_mib_ops = {
1543	.init = ipv4_mib_init_net,
1544	.exit = ipv4_mib_exit_net,
1545};
1546
1547static int __init init_ipv4_mibs(void)
1548{
1549	return register_pernet_subsys(&ipv4_mib_ops);
1550}
1551
1552static int ipv4_proc_init(void);
1553
1554/*
1555 *	IP protocol layer initialiser
1556 */
1557
1558static struct packet_type ip_packet_type __read_mostly = {
1559	.type = cpu_to_be16(ETH_P_IP),
1560	.func = ip_rcv,
1561	.gso_send_check = inet_gso_send_check,
1562	.gso_segment = inet_gso_segment,
1563	.gro_receive = inet_gro_receive,
1564	.gro_complete = inet_gro_complete,
1565};
1566
1567static int __init inet_init(void)
1568{
1569	struct sk_buff *dummy_skb;
1570	struct inet_protosw *q;
1571	struct list_head *r;
1572	int rc = -EINVAL;
1573
1574	BUILD_BUG_ON(sizeof(struct inet_skb_parm) > sizeof(dummy_skb->cb));
1575
1576	rc = proto_register(&tcp_prot, 1);
1577	if (rc)
1578		goto out;
1579
1580	rc = proto_register(&udp_prot, 1);
1581	if (rc)
1582		goto out_unregister_tcp_proto;
1583
1584	rc = proto_register(&raw_prot, 1);
1585	if (rc)
1586		goto out_unregister_udp_proto;
1587
1588	/*
1589	 *	Tell SOCKET that we are alive...
1590	 */
1591
1592	(void)sock_register(&inet_family_ops);
1593
1594#ifdef CONFIG_SYSCTL
1595	ip_static_sysctl_init();
1596#endif
1597
1598	/*
1599	 *	Add all the base protocols.
1600	 */
1601
1602	if (inet_add_protocol(&icmp_protocol, IPPROTO_ICMP) < 0)
1603		printk(KERN_CRIT "inet_init: Cannot add ICMP protocol\n");
1604	if (inet_add_protocol(&udp_protocol, IPPROTO_UDP) < 0)
1605		printk(KERN_CRIT "inet_init: Cannot add UDP protocol\n");
1606	if (inet_add_protocol(&tcp_protocol, IPPROTO_TCP) < 0)
1607		printk(KERN_CRIT "inet_init: Cannot add TCP protocol\n");
1608#ifdef CONFIG_IP_MULTICAST
1609	if (inet_add_protocol(&igmp_protocol, IPPROTO_IGMP) < 0)
1610		printk(KERN_CRIT "inet_init: Cannot add IGMP protocol\n");
1611#endif
1612
1613	/* Register the socket-side information for inet_create. */
1614	for (r = &inetsw[0]; r < &inetsw[SOCK_MAX]; ++r)
1615		INIT_LIST_HEAD(r);
1616
1617	for (q = inetsw_array; q < &inetsw_array[INETSW_ARRAY_LEN]; ++q)
1618		inet_register_protosw(q);
1619
1620	/*
1621	 *	Set the ARP module up
1622	 */
1623
1624	arp_init();
1625
1626	/*
1627	 *	Set the IP module up
1628	 */
1629
1630	ip_init();
1631
1632	tcp_v4_init();
1633
1634	/* Setup TCP slab cache for open requests. */
1635	tcp_init();
1636
1637	/* Setup UDP memory threshold */
1638	udp_init();
1639
1640	/* Add UDP-Lite (RFC 3828) */
1641	udplite4_register();
1642
1643	/*
1644	 *	Set the ICMP layer up
1645	 */
1646
1647	if (icmp_init() < 0)
1648		panic("Failed to create the ICMP control socket.\n");
1649
1650	/*
1651	 *	Initialise the multicast router
1652	 */
1653#if defined(CONFIG_IP_MROUTE)
1654	if (ip_mr_init())
1655		printk(KERN_CRIT "inet_init: Cannot init ipv4 mroute\n");
1656#endif
1657	/*
1658	 *	Initialise per-cpu ipv4 mibs
1659	 */
1660
1661	if (init_ipv4_mibs())
1662		printk(KERN_CRIT "inet_init: Cannot init ipv4 mibs\n");
1663
1664	ipv4_proc_init();
1665
1666	ipfrag_init();
1667
1668	dev_add_pack(&ip_packet_type);
1669
1670	rc = 0;
1671out:
1672	return rc;
1673out_unregister_udp_proto:
1674	proto_unregister(&udp_prot);
1675out_unregister_tcp_proto:
1676	proto_unregister(&tcp_prot);
1677	goto out;
1678}
1679
1680fs_initcall(inet_init);
1681
1682/* ------------------------------------------------------------------------ */
1683
1684#ifdef CONFIG_PROC_FS
1685static int __init ipv4_proc_init(void)
1686{
1687	int rc = 0;
1688
1689	if (raw_proc_init())
1690		goto out_raw;
1691	if (tcp4_proc_init())
1692		goto out_tcp;
1693	if (udp4_proc_init())
1694		goto out_udp;
1695	if (ip_misc_proc_init())
1696		goto out_misc;
1697out:
1698	return rc;
1699out_misc:
1700	udp4_proc_exit();
1701out_udp:
1702	tcp4_proc_exit();
1703out_tcp:
1704	raw_proc_exit();
1705out_raw:
1706	rc = -ENOMEM;
1707	goto out;
1708}
1709
1710#else /* CONFIG_PROC_FS */
1711static int __init ipv4_proc_init(void)
1712{
1713	return 0;
1714}
1715#endif /* CONFIG_PROC_FS */
1716
1717MODULE_ALIAS_NETPROTO(PF_INET);
1718
1719