af_inet.c revision c319b4d76b9e583a5d88d6bf190e079c4e43213d
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 <net/ping.h>
109#include <linux/skbuff.h>
110#include <net/sock.h>
111#include <net/raw.h>
112#include <net/icmp.h>
113#include <net/ipip.h>
114#include <net/inet_common.h>
115#include <net/xfrm.h>
116#include <net/net_namespace.h>
117#ifdef CONFIG_IP_MROUTE
118#include <linux/mroute.h>
119#endif
120
121
122/* The inetsw table contains everything that inet_create needs to
123 * build a new socket.
124 */
125static struct list_head inetsw[SOCK_MAX];
126static DEFINE_SPINLOCK(inetsw_lock);
127
128struct ipv4_config ipv4_config;
129EXPORT_SYMBOL(ipv4_config);
130
131/* New destruction routine */
132
133void inet_sock_destruct(struct sock *sk)
134{
135	struct inet_sock *inet = inet_sk(sk);
136
137	__skb_queue_purge(&sk->sk_receive_queue);
138	__skb_queue_purge(&sk->sk_error_queue);
139
140	sk_mem_reclaim(sk);
141
142	if (sk->sk_type == SOCK_STREAM && sk->sk_state != TCP_CLOSE) {
143		pr_err("Attempt to release TCP socket in state %d %p\n",
144		       sk->sk_state, sk);
145		return;
146	}
147	if (!sock_flag(sk, SOCK_DEAD)) {
148		pr_err("Attempt to release alive inet socket %p\n", sk);
149		return;
150	}
151
152	WARN_ON(atomic_read(&sk->sk_rmem_alloc));
153	WARN_ON(atomic_read(&sk->sk_wmem_alloc));
154	WARN_ON(sk->sk_wmem_queued);
155	WARN_ON(sk->sk_forward_alloc);
156
157	kfree(rcu_dereference_protected(inet->inet_opt, 1));
158	dst_release(rcu_dereference_check(sk->sk_dst_cache, 1));
159	sk_refcnt_debug_dec(sk);
160}
161EXPORT_SYMBOL(inet_sock_destruct);
162
163/*
164 *	The routines beyond this point handle the behaviour of an AF_INET
165 *	socket object. Mostly it punts to the subprotocols of IP to do
166 *	the work.
167 */
168
169/*
170 *	Automatically bind an unbound socket.
171 */
172
173static int inet_autobind(struct sock *sk)
174{
175	struct inet_sock *inet;
176	/* We may need to bind the socket. */
177	lock_sock(sk);
178	inet = inet_sk(sk);
179	if (!inet->inet_num) {
180		if (sk->sk_prot->get_port(sk, 0)) {
181			release_sock(sk);
182			return -EAGAIN;
183		}
184		inet->inet_sport = htons(inet->inet_num);
185	}
186	release_sock(sk);
187	return 0;
188}
189
190/*
191 *	Move a socket into listening state.
192 */
193int inet_listen(struct socket *sock, int backlog)
194{
195	struct sock *sk = sock->sk;
196	unsigned char old_state;
197	int err;
198
199	lock_sock(sk);
200
201	err = -EINVAL;
202	if (sock->state != SS_UNCONNECTED || sock->type != SOCK_STREAM)
203		goto out;
204
205	old_state = sk->sk_state;
206	if (!((1 << old_state) & (TCPF_CLOSE | TCPF_LISTEN)))
207		goto out;
208
209	/* Really, if the socket is already in listen state
210	 * we can only allow the backlog to be adjusted.
211	 */
212	if (old_state != TCP_LISTEN) {
213		err = inet_csk_listen_start(sk, backlog);
214		if (err)
215			goto out;
216	}
217	sk->sk_max_ack_backlog = backlog;
218	err = 0;
219
220out:
221	release_sock(sk);
222	return err;
223}
224EXPORT_SYMBOL(inet_listen);
225
226u32 inet_ehash_secret __read_mostly;
227EXPORT_SYMBOL(inet_ehash_secret);
228
229/*
230 * inet_ehash_secret must be set exactly once
231 */
232void build_ehash_secret(void)
233{
234	u32 rnd;
235
236	do {
237		get_random_bytes(&rnd, sizeof(rnd));
238	} while (rnd == 0);
239
240	cmpxchg(&inet_ehash_secret, 0, rnd);
241}
242EXPORT_SYMBOL(build_ehash_secret);
243
244static inline int inet_netns_ok(struct net *net, int protocol)
245{
246	int hash;
247	const struct net_protocol *ipprot;
248
249	if (net_eq(net, &init_net))
250		return 1;
251
252	hash = protocol & (MAX_INET_PROTOS - 1);
253	ipprot = rcu_dereference(inet_protos[hash]);
254
255	if (ipprot == NULL)
256		/* raw IP is OK */
257		return 1;
258	return ipprot->netns_ok;
259}
260
261/*
262 *	Create an inet socket.
263 */
264
265static int inet_create(struct net *net, struct socket *sock, int protocol,
266		       int kern)
267{
268	struct sock *sk;
269	struct inet_protosw *answer;
270	struct inet_sock *inet;
271	struct proto *answer_prot;
272	unsigned char answer_flags;
273	char answer_no_check;
274	int try_loading_module = 0;
275	int err;
276
277	if (unlikely(!inet_ehash_secret))
278		if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM)
279			build_ehash_secret();
280
281	sock->state = SS_UNCONNECTED;
282
283	/* Look for the requested type/protocol pair. */
284lookup_protocol:
285	err = -ESOCKTNOSUPPORT;
286	rcu_read_lock();
287	list_for_each_entry_rcu(answer, &inetsw[sock->type], list) {
288
289		err = 0;
290		/* Check the non-wild match. */
291		if (protocol == answer->protocol) {
292			if (protocol != IPPROTO_IP)
293				break;
294		} else {
295			/* Check for the two wild cases. */
296			if (IPPROTO_IP == protocol) {
297				protocol = answer->protocol;
298				break;
299			}
300			if (IPPROTO_IP == answer->protocol)
301				break;
302		}
303		err = -EPROTONOSUPPORT;
304	}
305
306	if (unlikely(err)) {
307		if (try_loading_module < 2) {
308			rcu_read_unlock();
309			/*
310			 * Be more specific, e.g. net-pf-2-proto-132-type-1
311			 * (net-pf-PF_INET-proto-IPPROTO_SCTP-type-SOCK_STREAM)
312			 */
313			if (++try_loading_module == 1)
314				request_module("net-pf-%d-proto-%d-type-%d",
315					       PF_INET, protocol, sock->type);
316			/*
317			 * Fall back to generic, e.g. net-pf-2-proto-132
318			 * (net-pf-PF_INET-proto-IPPROTO_SCTP)
319			 */
320			else
321				request_module("net-pf-%d-proto-%d",
322					       PF_INET, protocol);
323			goto lookup_protocol;
324		} else
325			goto out_rcu_unlock;
326	}
327
328	err = -EPERM;
329	if (sock->type == SOCK_RAW && !kern && !capable(CAP_NET_RAW))
330		goto out_rcu_unlock;
331
332	err = -EAFNOSUPPORT;
333	if (!inet_netns_ok(net, protocol))
334		goto out_rcu_unlock;
335
336	sock->ops = answer->ops;
337	answer_prot = answer->prot;
338	answer_no_check = answer->no_check;
339	answer_flags = answer->flags;
340	rcu_read_unlock();
341
342	WARN_ON(answer_prot->slab == NULL);
343
344	err = -ENOBUFS;
345	sk = sk_alloc(net, PF_INET, GFP_KERNEL, answer_prot);
346	if (sk == NULL)
347		goto out;
348
349	err = 0;
350	sk->sk_no_check = answer_no_check;
351	if (INET_PROTOSW_REUSE & answer_flags)
352		sk->sk_reuse = 1;
353
354	inet = inet_sk(sk);
355	inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
356
357	inet->nodefrag = 0;
358
359	if (SOCK_RAW == sock->type) {
360		inet->inet_num = protocol;
361		if (IPPROTO_RAW == protocol)
362			inet->hdrincl = 1;
363	}
364
365	if (ipv4_config.no_pmtu_disc)
366		inet->pmtudisc = IP_PMTUDISC_DONT;
367	else
368		inet->pmtudisc = IP_PMTUDISC_WANT;
369
370	inet->inet_id = 0;
371
372	sock_init_data(sock, sk);
373
374	sk->sk_destruct	   = inet_sock_destruct;
375	sk->sk_protocol	   = protocol;
376	sk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
377
378	inet->uc_ttl	= -1;
379	inet->mc_loop	= 1;
380	inet->mc_ttl	= 1;
381	inet->mc_all	= 1;
382	inet->mc_index	= 0;
383	inet->mc_list	= NULL;
384
385	sk_refcnt_debug_inc(sk);
386
387	if (inet->inet_num) {
388		/* It assumes that any protocol which allows
389		 * the user to assign a number at socket
390		 * creation time automatically
391		 * shares.
392		 */
393		inet->inet_sport = htons(inet->inet_num);
394		/* Add to protocol hash chains. */
395		sk->sk_prot->hash(sk);
396	}
397
398	if (sk->sk_prot->init) {
399		err = sk->sk_prot->init(sk);
400		if (err)
401			sk_common_release(sk);
402	}
403out:
404	return err;
405out_rcu_unlock:
406	rcu_read_unlock();
407	goto out;
408}
409
410
411/*
412 *	The peer socket should always be NULL (or else). When we call this
413 *	function we are destroying the object and from then on nobody
414 *	should refer to it.
415 */
416int inet_release(struct socket *sock)
417{
418	struct sock *sk = sock->sk;
419
420	if (sk) {
421		long timeout;
422
423		sock_rps_reset_flow(sk);
424
425		/* Applications forget to leave groups before exiting */
426		ip_mc_drop_socket(sk);
427
428		/* If linger is set, we don't return until the close
429		 * is complete.  Otherwise we return immediately. The
430		 * actually closing is done the same either way.
431		 *
432		 * If the close is due to the process exiting, we never
433		 * linger..
434		 */
435		timeout = 0;
436		if (sock_flag(sk, SOCK_LINGER) &&
437		    !(current->flags & PF_EXITING))
438			timeout = sk->sk_lingertime;
439		sock->sk = NULL;
440		sk->sk_prot->close(sk, timeout);
441	}
442	return 0;
443}
444EXPORT_SYMBOL(inet_release);
445
446/* It is off by default, see below. */
447int sysctl_ip_nonlocal_bind __read_mostly;
448EXPORT_SYMBOL(sysctl_ip_nonlocal_bind);
449
450int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
451{
452	struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
453	struct sock *sk = sock->sk;
454	struct inet_sock *inet = inet_sk(sk);
455	unsigned short snum;
456	int chk_addr_ret;
457	int err;
458
459	/* If the socket has its own bind function then use it. (RAW) */
460	if (sk->sk_prot->bind) {
461		err = sk->sk_prot->bind(sk, uaddr, addr_len);
462		goto out;
463	}
464	err = -EINVAL;
465	if (addr_len < sizeof(struct sockaddr_in))
466		goto out;
467
468	chk_addr_ret = inet_addr_type(sock_net(sk), addr->sin_addr.s_addr);
469
470	/* Not specified by any standard per-se, however it breaks too
471	 * many applications when removed.  It is unfortunate since
472	 * allowing applications to make a non-local bind solves
473	 * several problems with systems using dynamic addressing.
474	 * (ie. your servers still start up even if your ISDN link
475	 *  is temporarily down)
476	 */
477	err = -EADDRNOTAVAIL;
478	if (!sysctl_ip_nonlocal_bind &&
479	    !(inet->freebind || inet->transparent) &&
480	    addr->sin_addr.s_addr != htonl(INADDR_ANY) &&
481	    chk_addr_ret != RTN_LOCAL &&
482	    chk_addr_ret != RTN_MULTICAST &&
483	    chk_addr_ret != RTN_BROADCAST)
484		goto out;
485
486	snum = ntohs(addr->sin_port);
487	err = -EACCES;
488	if (snum && snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
489		goto out;
490
491	/*      We keep a pair of addresses. rcv_saddr is the one
492	 *      used by hash lookups, and saddr is used for transmit.
493	 *
494	 *      In the BSD API these are the same except where it
495	 *      would be illegal to use them (multicast/broadcast) in
496	 *      which case the sending device address is used.
497	 */
498	lock_sock(sk);
499
500	/* Check these errors (active socket, double bind). */
501	err = -EINVAL;
502	if (sk->sk_state != TCP_CLOSE || inet->inet_num)
503		goto out_release_sock;
504
505	inet->inet_rcv_saddr = inet->inet_saddr = addr->sin_addr.s_addr;
506	if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST)
507		inet->inet_saddr = 0;  /* Use device */
508
509	/* Make sure we are allowed to bind here. */
510	if (sk->sk_prot->get_port(sk, snum)) {
511		inet->inet_saddr = inet->inet_rcv_saddr = 0;
512		err = -EADDRINUSE;
513		goto out_release_sock;
514	}
515
516	if (inet->inet_rcv_saddr)
517		sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
518	if (snum)
519		sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
520	inet->inet_sport = htons(inet->inet_num);
521	inet->inet_daddr = 0;
522	inet->inet_dport = 0;
523	sk_dst_reset(sk);
524	err = 0;
525out_release_sock:
526	release_sock(sk);
527out:
528	return err;
529}
530EXPORT_SYMBOL(inet_bind);
531
532int inet_dgram_connect(struct socket *sock, struct sockaddr * uaddr,
533		       int addr_len, int flags)
534{
535	struct sock *sk = sock->sk;
536
537	if (addr_len < sizeof(uaddr->sa_family))
538		return -EINVAL;
539	if (uaddr->sa_family == AF_UNSPEC)
540		return sk->sk_prot->disconnect(sk, flags);
541
542	if (!inet_sk(sk)->inet_num && inet_autobind(sk))
543		return -EAGAIN;
544	return sk->sk_prot->connect(sk, (struct sockaddr *)uaddr, addr_len);
545}
546EXPORT_SYMBOL(inet_dgram_connect);
547
548static long inet_wait_for_connect(struct sock *sk, long timeo)
549{
550	DEFINE_WAIT(wait);
551
552	prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
553
554	/* Basic assumption: if someone sets sk->sk_err, he _must_
555	 * change state of the socket from TCP_SYN_*.
556	 * Connect() does not allow to get error notifications
557	 * without closing the socket.
558	 */
559	while ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
560		release_sock(sk);
561		timeo = schedule_timeout(timeo);
562		lock_sock(sk);
563		if (signal_pending(current) || !timeo)
564			break;
565		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
566	}
567	finish_wait(sk_sleep(sk), &wait);
568	return timeo;
569}
570
571/*
572 *	Connect to a remote host. There is regrettably still a little
573 *	TCP 'magic' in here.
574 */
575int inet_stream_connect(struct socket *sock, struct sockaddr *uaddr,
576			int addr_len, int flags)
577{
578	struct sock *sk = sock->sk;
579	int err;
580	long timeo;
581
582	if (addr_len < sizeof(uaddr->sa_family))
583		return -EINVAL;
584
585	lock_sock(sk);
586
587	if (uaddr->sa_family == AF_UNSPEC) {
588		err = sk->sk_prot->disconnect(sk, flags);
589		sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
590		goto out;
591	}
592
593	switch (sock->state) {
594	default:
595		err = -EINVAL;
596		goto out;
597	case SS_CONNECTED:
598		err = -EISCONN;
599		goto out;
600	case SS_CONNECTING:
601		err = -EALREADY;
602		/* Fall out of switch with err, set for this state */
603		break;
604	case SS_UNCONNECTED:
605		err = -EISCONN;
606		if (sk->sk_state != TCP_CLOSE)
607			goto out;
608
609		err = sk->sk_prot->connect(sk, uaddr, addr_len);
610		if (err < 0)
611			goto out;
612
613		sock->state = SS_CONNECTING;
614
615		/* Just entered SS_CONNECTING state; the only
616		 * difference is that return value in non-blocking
617		 * case is EINPROGRESS, rather than EALREADY.
618		 */
619		err = -EINPROGRESS;
620		break;
621	}
622
623	timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
624
625	if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
626		/* Error code is set above */
627		if (!timeo || !inet_wait_for_connect(sk, timeo))
628			goto out;
629
630		err = sock_intr_errno(timeo);
631		if (signal_pending(current))
632			goto out;
633	}
634
635	/* Connection was closed by RST, timeout, ICMP error
636	 * or another process disconnected us.
637	 */
638	if (sk->sk_state == TCP_CLOSE)
639		goto sock_error;
640
641	/* sk->sk_err may be not zero now, if RECVERR was ordered by user
642	 * and error was received after socket entered established state.
643	 * Hence, it is handled normally after connect() return successfully.
644	 */
645
646	sock->state = SS_CONNECTED;
647	err = 0;
648out:
649	release_sock(sk);
650	return err;
651
652sock_error:
653	err = sock_error(sk) ? : -ECONNABORTED;
654	sock->state = SS_UNCONNECTED;
655	if (sk->sk_prot->disconnect(sk, flags))
656		sock->state = SS_DISCONNECTING;
657	goto out;
658}
659EXPORT_SYMBOL(inet_stream_connect);
660
661/*
662 *	Accept a pending connection. The TCP layer now gives BSD semantics.
663 */
664
665int inet_accept(struct socket *sock, struct socket *newsock, int flags)
666{
667	struct sock *sk1 = sock->sk;
668	int err = -EINVAL;
669	struct sock *sk2 = sk1->sk_prot->accept(sk1, flags, &err);
670
671	if (!sk2)
672		goto do_err;
673
674	lock_sock(sk2);
675
676	WARN_ON(!((1 << sk2->sk_state) &
677		  (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT | TCPF_CLOSE)));
678
679	sock_graft(sk2, newsock);
680
681	newsock->state = SS_CONNECTED;
682	err = 0;
683	release_sock(sk2);
684do_err:
685	return err;
686}
687EXPORT_SYMBOL(inet_accept);
688
689
690/*
691 *	This does both peername and sockname.
692 */
693int inet_getname(struct socket *sock, struct sockaddr *uaddr,
694			int *uaddr_len, int peer)
695{
696	struct sock *sk		= sock->sk;
697	struct inet_sock *inet	= inet_sk(sk);
698	DECLARE_SOCKADDR(struct sockaddr_in *, sin, uaddr);
699
700	sin->sin_family = AF_INET;
701	if (peer) {
702		if (!inet->inet_dport ||
703		    (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
704		     peer == 1))
705			return -ENOTCONN;
706		sin->sin_port = inet->inet_dport;
707		sin->sin_addr.s_addr = inet->inet_daddr;
708	} else {
709		__be32 addr = inet->inet_rcv_saddr;
710		if (!addr)
711			addr = inet->inet_saddr;
712		sin->sin_port = inet->inet_sport;
713		sin->sin_addr.s_addr = addr;
714	}
715	memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
716	*uaddr_len = sizeof(*sin);
717	return 0;
718}
719EXPORT_SYMBOL(inet_getname);
720
721int inet_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
722		 size_t size)
723{
724	struct sock *sk = sock->sk;
725
726	sock_rps_record_flow(sk);
727
728	/* We may need to bind the socket. */
729	if (!inet_sk(sk)->inet_num && !sk->sk_prot->no_autobind &&
730	    inet_autobind(sk))
731		return -EAGAIN;
732
733	return sk->sk_prot->sendmsg(iocb, sk, msg, size);
734}
735EXPORT_SYMBOL(inet_sendmsg);
736
737ssize_t inet_sendpage(struct socket *sock, struct page *page, int offset,
738		      size_t size, int flags)
739{
740	struct sock *sk = sock->sk;
741
742	sock_rps_record_flow(sk);
743
744	/* We may need to bind the socket. */
745	if (!inet_sk(sk)->inet_num && !sk->sk_prot->no_autobind &&
746	    inet_autobind(sk))
747		return -EAGAIN;
748
749	if (sk->sk_prot->sendpage)
750		return sk->sk_prot->sendpage(sk, page, offset, size, flags);
751	return sock_no_sendpage(sock, page, offset, size, flags);
752}
753EXPORT_SYMBOL(inet_sendpage);
754
755int inet_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
756		 size_t size, int flags)
757{
758	struct sock *sk = sock->sk;
759	int addr_len = 0;
760	int err;
761
762	sock_rps_record_flow(sk);
763
764	err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT,
765				   flags & ~MSG_DONTWAIT, &addr_len);
766	if (err >= 0)
767		msg->msg_namelen = addr_len;
768	return err;
769}
770EXPORT_SYMBOL(inet_recvmsg);
771
772int inet_shutdown(struct socket *sock, int how)
773{
774	struct sock *sk = sock->sk;
775	int err = 0;
776
777	/* This should really check to make sure
778	 * the socket is a TCP socket. (WHY AC...)
779	 */
780	how++; /* maps 0->1 has the advantage of making bit 1 rcvs and
781		       1->2 bit 2 snds.
782		       2->3 */
783	if ((how & ~SHUTDOWN_MASK) || !how)	/* MAXINT->0 */
784		return -EINVAL;
785
786	lock_sock(sk);
787	if (sock->state == SS_CONNECTING) {
788		if ((1 << sk->sk_state) &
789		    (TCPF_SYN_SENT | TCPF_SYN_RECV | TCPF_CLOSE))
790			sock->state = SS_DISCONNECTING;
791		else
792			sock->state = SS_CONNECTED;
793	}
794
795	switch (sk->sk_state) {
796	case TCP_CLOSE:
797		err = -ENOTCONN;
798		/* Hack to wake up other listeners, who can poll for
799		   POLLHUP, even on eg. unconnected UDP sockets -- RR */
800	default:
801		sk->sk_shutdown |= how;
802		if (sk->sk_prot->shutdown)
803			sk->sk_prot->shutdown(sk, how);
804		break;
805
806	/* Remaining two branches are temporary solution for missing
807	 * close() in multithreaded environment. It is _not_ a good idea,
808	 * but we have no choice until close() is repaired at VFS level.
809	 */
810	case TCP_LISTEN:
811		if (!(how & RCV_SHUTDOWN))
812			break;
813		/* Fall through */
814	case TCP_SYN_SENT:
815		err = sk->sk_prot->disconnect(sk, O_NONBLOCK);
816		sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
817		break;
818	}
819
820	/* Wake up anyone sleeping in poll. */
821	sk->sk_state_change(sk);
822	release_sock(sk);
823	return err;
824}
825EXPORT_SYMBOL(inet_shutdown);
826
827/*
828 *	ioctl() calls you can issue on an INET socket. Most of these are
829 *	device configuration and stuff and very rarely used. Some ioctls
830 *	pass on to the socket itself.
831 *
832 *	NOTE: I like the idea of a module for the config stuff. ie ifconfig
833 *	loads the devconfigure module does its configuring and unloads it.
834 *	There's a good 20K of config code hanging around the kernel.
835 */
836
837int inet_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
838{
839	struct sock *sk = sock->sk;
840	int err = 0;
841	struct net *net = sock_net(sk);
842
843	switch (cmd) {
844	case SIOCGSTAMP:
845		err = sock_get_timestamp(sk, (struct timeval __user *)arg);
846		break;
847	case SIOCGSTAMPNS:
848		err = sock_get_timestampns(sk, (struct timespec __user *)arg);
849		break;
850	case SIOCADDRT:
851	case SIOCDELRT:
852	case SIOCRTMSG:
853		err = ip_rt_ioctl(net, cmd, (void __user *)arg);
854		break;
855	case SIOCDARP:
856	case SIOCGARP:
857	case SIOCSARP:
858		err = arp_ioctl(net, cmd, (void __user *)arg);
859		break;
860	case SIOCGIFADDR:
861	case SIOCSIFADDR:
862	case SIOCGIFBRDADDR:
863	case SIOCSIFBRDADDR:
864	case SIOCGIFNETMASK:
865	case SIOCSIFNETMASK:
866	case SIOCGIFDSTADDR:
867	case SIOCSIFDSTADDR:
868	case SIOCSIFPFLAGS:
869	case SIOCGIFPFLAGS:
870	case SIOCSIFFLAGS:
871		err = devinet_ioctl(net, cmd, (void __user *)arg);
872		break;
873	default:
874		if (sk->sk_prot->ioctl)
875			err = sk->sk_prot->ioctl(sk, cmd, arg);
876		else
877			err = -ENOIOCTLCMD;
878		break;
879	}
880	return err;
881}
882EXPORT_SYMBOL(inet_ioctl);
883
884#ifdef CONFIG_COMPAT
885int inet_compat_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
886{
887	struct sock *sk = sock->sk;
888	int err = -ENOIOCTLCMD;
889
890	if (sk->sk_prot->compat_ioctl)
891		err = sk->sk_prot->compat_ioctl(sk, cmd, arg);
892
893	return err;
894}
895#endif
896
897const struct proto_ops inet_stream_ops = {
898	.family		   = PF_INET,
899	.owner		   = THIS_MODULE,
900	.release	   = inet_release,
901	.bind		   = inet_bind,
902	.connect	   = inet_stream_connect,
903	.socketpair	   = sock_no_socketpair,
904	.accept		   = inet_accept,
905	.getname	   = inet_getname,
906	.poll		   = tcp_poll,
907	.ioctl		   = inet_ioctl,
908	.listen		   = inet_listen,
909	.shutdown	   = inet_shutdown,
910	.setsockopt	   = sock_common_setsockopt,
911	.getsockopt	   = sock_common_getsockopt,
912	.sendmsg	   = inet_sendmsg,
913	.recvmsg	   = inet_recvmsg,
914	.mmap		   = sock_no_mmap,
915	.sendpage	   = inet_sendpage,
916	.splice_read	   = tcp_splice_read,
917#ifdef CONFIG_COMPAT
918	.compat_setsockopt = compat_sock_common_setsockopt,
919	.compat_getsockopt = compat_sock_common_getsockopt,
920	.compat_ioctl	   = inet_compat_ioctl,
921#endif
922};
923EXPORT_SYMBOL(inet_stream_ops);
924
925const struct proto_ops inet_dgram_ops = {
926	.family		   = PF_INET,
927	.owner		   = THIS_MODULE,
928	.release	   = inet_release,
929	.bind		   = inet_bind,
930	.connect	   = inet_dgram_connect,
931	.socketpair	   = sock_no_socketpair,
932	.accept		   = sock_no_accept,
933	.getname	   = inet_getname,
934	.poll		   = udp_poll,
935	.ioctl		   = inet_ioctl,
936	.listen		   = sock_no_listen,
937	.shutdown	   = inet_shutdown,
938	.setsockopt	   = sock_common_setsockopt,
939	.getsockopt	   = sock_common_getsockopt,
940	.sendmsg	   = inet_sendmsg,
941	.recvmsg	   = inet_recvmsg,
942	.mmap		   = sock_no_mmap,
943	.sendpage	   = inet_sendpage,
944#ifdef CONFIG_COMPAT
945	.compat_setsockopt = compat_sock_common_setsockopt,
946	.compat_getsockopt = compat_sock_common_getsockopt,
947	.compat_ioctl	   = inet_compat_ioctl,
948#endif
949};
950EXPORT_SYMBOL(inet_dgram_ops);
951
952/*
953 * For SOCK_RAW sockets; should be the same as inet_dgram_ops but without
954 * udp_poll
955 */
956static const struct proto_ops inet_sockraw_ops = {
957	.family		   = PF_INET,
958	.owner		   = THIS_MODULE,
959	.release	   = inet_release,
960	.bind		   = inet_bind,
961	.connect	   = inet_dgram_connect,
962	.socketpair	   = sock_no_socketpair,
963	.accept		   = sock_no_accept,
964	.getname	   = inet_getname,
965	.poll		   = datagram_poll,
966	.ioctl		   = inet_ioctl,
967	.listen		   = sock_no_listen,
968	.shutdown	   = inet_shutdown,
969	.setsockopt	   = sock_common_setsockopt,
970	.getsockopt	   = sock_common_getsockopt,
971	.sendmsg	   = inet_sendmsg,
972	.recvmsg	   = inet_recvmsg,
973	.mmap		   = sock_no_mmap,
974	.sendpage	   = inet_sendpage,
975#ifdef CONFIG_COMPAT
976	.compat_setsockopt = compat_sock_common_setsockopt,
977	.compat_getsockopt = compat_sock_common_getsockopt,
978	.compat_ioctl	   = inet_compat_ioctl,
979#endif
980};
981
982static const struct net_proto_family inet_family_ops = {
983	.family = PF_INET,
984	.create = inet_create,
985	.owner	= THIS_MODULE,
986};
987
988/* Upon startup we insert all the elements in inetsw_array[] into
989 * the linked list inetsw.
990 */
991static struct inet_protosw inetsw_array[] =
992{
993	{
994		.type =       SOCK_STREAM,
995		.protocol =   IPPROTO_TCP,
996		.prot =       &tcp_prot,
997		.ops =        &inet_stream_ops,
998		.no_check =   0,
999		.flags =      INET_PROTOSW_PERMANENT |
1000			      INET_PROTOSW_ICSK,
1001	},
1002
1003	{
1004		.type =       SOCK_DGRAM,
1005		.protocol =   IPPROTO_UDP,
1006		.prot =       &udp_prot,
1007		.ops =        &inet_dgram_ops,
1008		.no_check =   UDP_CSUM_DEFAULT,
1009		.flags =      INET_PROTOSW_PERMANENT,
1010       },
1011
1012       {
1013		.type =       SOCK_DGRAM,
1014		.protocol =   IPPROTO_ICMP,
1015		.prot =       &ping_prot,
1016		.ops =        &inet_dgram_ops,
1017		.no_check =   UDP_CSUM_DEFAULT,
1018		.flags =      INET_PROTOSW_REUSE,
1019       },
1020
1021       {
1022	       .type =       SOCK_RAW,
1023	       .protocol =   IPPROTO_IP,	/* wild card */
1024	       .prot =       &raw_prot,
1025	       .ops =        &inet_sockraw_ops,
1026	       .no_check =   UDP_CSUM_DEFAULT,
1027	       .flags =      INET_PROTOSW_REUSE,
1028       }
1029};
1030
1031#define INETSW_ARRAY_LEN ARRAY_SIZE(inetsw_array)
1032
1033void inet_register_protosw(struct inet_protosw *p)
1034{
1035	struct list_head *lh;
1036	struct inet_protosw *answer;
1037	int protocol = p->protocol;
1038	struct list_head *last_perm;
1039
1040	spin_lock_bh(&inetsw_lock);
1041
1042	if (p->type >= SOCK_MAX)
1043		goto out_illegal;
1044
1045	/* If we are trying to override a permanent protocol, bail. */
1046	answer = NULL;
1047	last_perm = &inetsw[p->type];
1048	list_for_each(lh, &inetsw[p->type]) {
1049		answer = list_entry(lh, struct inet_protosw, list);
1050
1051		/* Check only the non-wild match. */
1052		if (INET_PROTOSW_PERMANENT & answer->flags) {
1053			if (protocol == answer->protocol)
1054				break;
1055			last_perm = lh;
1056		}
1057
1058		answer = NULL;
1059	}
1060	if (answer)
1061		goto out_permanent;
1062
1063	/* Add the new entry after the last permanent entry if any, so that
1064	 * the new entry does not override a permanent entry when matched with
1065	 * a wild-card protocol. But it is allowed to override any existing
1066	 * non-permanent entry.  This means that when we remove this entry, the
1067	 * system automatically returns to the old behavior.
1068	 */
1069	list_add_rcu(&p->list, last_perm);
1070out:
1071	spin_unlock_bh(&inetsw_lock);
1072
1073	return;
1074
1075out_permanent:
1076	printk(KERN_ERR "Attempt to override permanent protocol %d.\n",
1077	       protocol);
1078	goto out;
1079
1080out_illegal:
1081	printk(KERN_ERR
1082	       "Ignoring attempt to register invalid socket type %d.\n",
1083	       p->type);
1084	goto out;
1085}
1086EXPORT_SYMBOL(inet_register_protosw);
1087
1088void inet_unregister_protosw(struct inet_protosw *p)
1089{
1090	if (INET_PROTOSW_PERMANENT & p->flags) {
1091		printk(KERN_ERR
1092		       "Attempt to unregister permanent protocol %d.\n",
1093		       p->protocol);
1094	} else {
1095		spin_lock_bh(&inetsw_lock);
1096		list_del_rcu(&p->list);
1097		spin_unlock_bh(&inetsw_lock);
1098
1099		synchronize_net();
1100	}
1101}
1102EXPORT_SYMBOL(inet_unregister_protosw);
1103
1104/*
1105 *      Shall we try to damage output packets if routing dev changes?
1106 */
1107
1108int sysctl_ip_dynaddr __read_mostly;
1109
1110static int inet_sk_reselect_saddr(struct sock *sk)
1111{
1112	struct inet_sock *inet = inet_sk(sk);
1113	__be32 old_saddr = inet->inet_saddr;
1114	__be32 daddr = inet->inet_daddr;
1115	struct flowi4 *fl4;
1116	struct rtable *rt;
1117	__be32 new_saddr;
1118	struct ip_options_rcu *inet_opt;
1119
1120	inet_opt = rcu_dereference_protected(inet->inet_opt,
1121					     sock_owned_by_user(sk));
1122	if (inet_opt && inet_opt->opt.srr)
1123		daddr = inet_opt->opt.faddr;
1124
1125	/* Query new route. */
1126	fl4 = &inet->cork.fl.u.ip4;
1127	rt = ip_route_connect(fl4, daddr, 0, RT_CONN_FLAGS(sk),
1128			      sk->sk_bound_dev_if, sk->sk_protocol,
1129			      inet->inet_sport, inet->inet_dport, sk, false);
1130	if (IS_ERR(rt))
1131		return PTR_ERR(rt);
1132
1133	sk_setup_caps(sk, &rt->dst);
1134
1135	new_saddr = fl4->saddr;
1136
1137	if (new_saddr == old_saddr)
1138		return 0;
1139
1140	if (sysctl_ip_dynaddr > 1) {
1141		printk(KERN_INFO "%s(): shifting inet->saddr from %pI4 to %pI4\n",
1142		       __func__, &old_saddr, &new_saddr);
1143	}
1144
1145	inet->inet_saddr = inet->inet_rcv_saddr = new_saddr;
1146
1147	/*
1148	 * XXX The only one ugly spot where we need to
1149	 * XXX really change the sockets identity after
1150	 * XXX it has entered the hashes. -DaveM
1151	 *
1152	 * Besides that, it does not check for connection
1153	 * uniqueness. Wait for troubles.
1154	 */
1155	__sk_prot_rehash(sk);
1156	return 0;
1157}
1158
1159int inet_sk_rebuild_header(struct sock *sk)
1160{
1161	struct inet_sock *inet = inet_sk(sk);
1162	struct rtable *rt = (struct rtable *)__sk_dst_check(sk, 0);
1163	__be32 daddr;
1164	struct ip_options_rcu *inet_opt;
1165	struct flowi4 *fl4;
1166	int err;
1167
1168	/* Route is OK, nothing to do. */
1169	if (rt)
1170		return 0;
1171
1172	/* Reroute. */
1173	rcu_read_lock();
1174	inet_opt = rcu_dereference(inet->inet_opt);
1175	daddr = inet->inet_daddr;
1176	if (inet_opt && inet_opt->opt.srr)
1177		daddr = inet_opt->opt.faddr;
1178	rcu_read_unlock();
1179	fl4 = &inet->cork.fl.u.ip4;
1180	rt = ip_route_output_ports(sock_net(sk), fl4, sk, daddr, inet->inet_saddr,
1181				   inet->inet_dport, inet->inet_sport,
1182				   sk->sk_protocol, RT_CONN_FLAGS(sk),
1183				   sk->sk_bound_dev_if);
1184	if (!IS_ERR(rt)) {
1185		err = 0;
1186		sk_setup_caps(sk, &rt->dst);
1187	} else {
1188		err = PTR_ERR(rt);
1189
1190		/* Routing failed... */
1191		sk->sk_route_caps = 0;
1192		/*
1193		 * Other protocols have to map its equivalent state to TCP_SYN_SENT.
1194		 * DCCP maps its DCCP_REQUESTING state to TCP_SYN_SENT. -acme
1195		 */
1196		if (!sysctl_ip_dynaddr ||
1197		    sk->sk_state != TCP_SYN_SENT ||
1198		    (sk->sk_userlocks & SOCK_BINDADDR_LOCK) ||
1199		    (err = inet_sk_reselect_saddr(sk)) != 0)
1200			sk->sk_err_soft = -err;
1201	}
1202
1203	return err;
1204}
1205EXPORT_SYMBOL(inet_sk_rebuild_header);
1206
1207static int inet_gso_send_check(struct sk_buff *skb)
1208{
1209	const struct iphdr *iph;
1210	const struct net_protocol *ops;
1211	int proto;
1212	int ihl;
1213	int err = -EINVAL;
1214
1215	if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
1216		goto out;
1217
1218	iph = ip_hdr(skb);
1219	ihl = iph->ihl * 4;
1220	if (ihl < sizeof(*iph))
1221		goto out;
1222
1223	if (unlikely(!pskb_may_pull(skb, ihl)))
1224		goto out;
1225
1226	__skb_pull(skb, ihl);
1227	skb_reset_transport_header(skb);
1228	iph = ip_hdr(skb);
1229	proto = iph->protocol & (MAX_INET_PROTOS - 1);
1230	err = -EPROTONOSUPPORT;
1231
1232	rcu_read_lock();
1233	ops = rcu_dereference(inet_protos[proto]);
1234	if (likely(ops && ops->gso_send_check))
1235		err = ops->gso_send_check(skb);
1236	rcu_read_unlock();
1237
1238out:
1239	return err;
1240}
1241
1242static struct sk_buff *inet_gso_segment(struct sk_buff *skb, u32 features)
1243{
1244	struct sk_buff *segs = ERR_PTR(-EINVAL);
1245	struct iphdr *iph;
1246	const struct net_protocol *ops;
1247	int proto;
1248	int ihl;
1249	int id;
1250	unsigned int offset = 0;
1251
1252	if (!(features & NETIF_F_V4_CSUM))
1253		features &= ~NETIF_F_SG;
1254
1255	if (unlikely(skb_shinfo(skb)->gso_type &
1256		     ~(SKB_GSO_TCPV4 |
1257		       SKB_GSO_UDP |
1258		       SKB_GSO_DODGY |
1259		       SKB_GSO_TCP_ECN |
1260		       0)))
1261		goto out;
1262
1263	if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
1264		goto out;
1265
1266	iph = ip_hdr(skb);
1267	ihl = iph->ihl * 4;
1268	if (ihl < sizeof(*iph))
1269		goto out;
1270
1271	if (unlikely(!pskb_may_pull(skb, ihl)))
1272		goto out;
1273
1274	__skb_pull(skb, ihl);
1275	skb_reset_transport_header(skb);
1276	iph = ip_hdr(skb);
1277	id = ntohs(iph->id);
1278	proto = iph->protocol & (MAX_INET_PROTOS - 1);
1279	segs = ERR_PTR(-EPROTONOSUPPORT);
1280
1281	rcu_read_lock();
1282	ops = rcu_dereference(inet_protos[proto]);
1283	if (likely(ops && ops->gso_segment))
1284		segs = ops->gso_segment(skb, features);
1285	rcu_read_unlock();
1286
1287	if (!segs || IS_ERR(segs))
1288		goto out;
1289
1290	skb = segs;
1291	do {
1292		iph = ip_hdr(skb);
1293		if (proto == IPPROTO_UDP) {
1294			iph->id = htons(id);
1295			iph->frag_off = htons(offset >> 3);
1296			if (skb->next != NULL)
1297				iph->frag_off |= htons(IP_MF);
1298			offset += (skb->len - skb->mac_len - iph->ihl * 4);
1299		} else
1300			iph->id = htons(id++);
1301		iph->tot_len = htons(skb->len - skb->mac_len);
1302		iph->check = 0;
1303		iph->check = ip_fast_csum(skb_network_header(skb), iph->ihl);
1304	} while ((skb = skb->next));
1305
1306out:
1307	return segs;
1308}
1309
1310static struct sk_buff **inet_gro_receive(struct sk_buff **head,
1311					 struct sk_buff *skb)
1312{
1313	const struct net_protocol *ops;
1314	struct sk_buff **pp = NULL;
1315	struct sk_buff *p;
1316	const struct iphdr *iph;
1317	unsigned int hlen;
1318	unsigned int off;
1319	unsigned int id;
1320	int flush = 1;
1321	int proto;
1322
1323	off = skb_gro_offset(skb);
1324	hlen = off + sizeof(*iph);
1325	iph = skb_gro_header_fast(skb, off);
1326	if (skb_gro_header_hard(skb, hlen)) {
1327		iph = skb_gro_header_slow(skb, hlen, off);
1328		if (unlikely(!iph))
1329			goto out;
1330	}
1331
1332	proto = iph->protocol & (MAX_INET_PROTOS - 1);
1333
1334	rcu_read_lock();
1335	ops = rcu_dereference(inet_protos[proto]);
1336	if (!ops || !ops->gro_receive)
1337		goto out_unlock;
1338
1339	if (*(u8 *)iph != 0x45)
1340		goto out_unlock;
1341
1342	if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1343		goto out_unlock;
1344
1345	id = ntohl(*(__be32 *)&iph->id);
1346	flush = (u16)((ntohl(*(__be32 *)iph) ^ skb_gro_len(skb)) | (id ^ IP_DF));
1347	id >>= 16;
1348
1349	for (p = *head; p; p = p->next) {
1350		struct iphdr *iph2;
1351
1352		if (!NAPI_GRO_CB(p)->same_flow)
1353			continue;
1354
1355		iph2 = ip_hdr(p);
1356
1357		if ((iph->protocol ^ iph2->protocol) |
1358		    (iph->tos ^ iph2->tos) |
1359		    ((__force u32)iph->saddr ^ (__force u32)iph2->saddr) |
1360		    ((__force u32)iph->daddr ^ (__force u32)iph2->daddr)) {
1361			NAPI_GRO_CB(p)->same_flow = 0;
1362			continue;
1363		}
1364
1365		/* All fields must match except length and checksum. */
1366		NAPI_GRO_CB(p)->flush |=
1367			(iph->ttl ^ iph2->ttl) |
1368			((u16)(ntohs(iph2->id) + NAPI_GRO_CB(p)->count) ^ id);
1369
1370		NAPI_GRO_CB(p)->flush |= flush;
1371	}
1372
1373	NAPI_GRO_CB(skb)->flush |= flush;
1374	skb_gro_pull(skb, sizeof(*iph));
1375	skb_set_transport_header(skb, skb_gro_offset(skb));
1376
1377	pp = ops->gro_receive(head, skb);
1378
1379out_unlock:
1380	rcu_read_unlock();
1381
1382out:
1383	NAPI_GRO_CB(skb)->flush |= flush;
1384
1385	return pp;
1386}
1387
1388static int inet_gro_complete(struct sk_buff *skb)
1389{
1390	const struct net_protocol *ops;
1391	struct iphdr *iph = ip_hdr(skb);
1392	int proto = iph->protocol & (MAX_INET_PROTOS - 1);
1393	int err = -ENOSYS;
1394	__be16 newlen = htons(skb->len - skb_network_offset(skb));
1395
1396	csum_replace2(&iph->check, iph->tot_len, newlen);
1397	iph->tot_len = newlen;
1398
1399	rcu_read_lock();
1400	ops = rcu_dereference(inet_protos[proto]);
1401	if (WARN_ON(!ops || !ops->gro_complete))
1402		goto out_unlock;
1403
1404	err = ops->gro_complete(skb);
1405
1406out_unlock:
1407	rcu_read_unlock();
1408
1409	return err;
1410}
1411
1412int inet_ctl_sock_create(struct sock **sk, unsigned short family,
1413			 unsigned short type, unsigned char protocol,
1414			 struct net *net)
1415{
1416	struct socket *sock;
1417	int rc = sock_create_kern(family, type, protocol, &sock);
1418
1419	if (rc == 0) {
1420		*sk = sock->sk;
1421		(*sk)->sk_allocation = GFP_ATOMIC;
1422		/*
1423		 * Unhash it so that IP input processing does not even see it,
1424		 * we do not wish this socket to see incoming packets.
1425		 */
1426		(*sk)->sk_prot->unhash(*sk);
1427
1428		sk_change_net(*sk, net);
1429	}
1430	return rc;
1431}
1432EXPORT_SYMBOL_GPL(inet_ctl_sock_create);
1433
1434unsigned long snmp_fold_field(void __percpu *mib[], int offt)
1435{
1436	unsigned long res = 0;
1437	int i;
1438
1439	for_each_possible_cpu(i) {
1440		res += *(((unsigned long *) per_cpu_ptr(mib[0], i)) + offt);
1441		res += *(((unsigned long *) per_cpu_ptr(mib[1], i)) + offt);
1442	}
1443	return res;
1444}
1445EXPORT_SYMBOL_GPL(snmp_fold_field);
1446
1447#if BITS_PER_LONG==32
1448
1449u64 snmp_fold_field64(void __percpu *mib[], int offt, size_t syncp_offset)
1450{
1451	u64 res = 0;
1452	int cpu;
1453
1454	for_each_possible_cpu(cpu) {
1455		void *bhptr, *userptr;
1456		struct u64_stats_sync *syncp;
1457		u64 v_bh, v_user;
1458		unsigned int start;
1459
1460		/* first mib used by softirq context, we must use _bh() accessors */
1461		bhptr = per_cpu_ptr(SNMP_STAT_BHPTR(mib), cpu);
1462		syncp = (struct u64_stats_sync *)(bhptr + syncp_offset);
1463		do {
1464			start = u64_stats_fetch_begin_bh(syncp);
1465			v_bh = *(((u64 *) bhptr) + offt);
1466		} while (u64_stats_fetch_retry_bh(syncp, start));
1467
1468		/* second mib used in USER context */
1469		userptr = per_cpu_ptr(SNMP_STAT_USRPTR(mib), cpu);
1470		syncp = (struct u64_stats_sync *)(userptr + syncp_offset);
1471		do {
1472			start = u64_stats_fetch_begin(syncp);
1473			v_user = *(((u64 *) userptr) + offt);
1474		} while (u64_stats_fetch_retry(syncp, start));
1475
1476		res += v_bh + v_user;
1477	}
1478	return res;
1479}
1480EXPORT_SYMBOL_GPL(snmp_fold_field64);
1481#endif
1482
1483int snmp_mib_init(void __percpu *ptr[2], size_t mibsize, size_t align)
1484{
1485	BUG_ON(ptr == NULL);
1486	ptr[0] = __alloc_percpu(mibsize, align);
1487	if (!ptr[0])
1488		goto err0;
1489	ptr[1] = __alloc_percpu(mibsize, align);
1490	if (!ptr[1])
1491		goto err1;
1492	return 0;
1493err1:
1494	free_percpu(ptr[0]);
1495	ptr[0] = NULL;
1496err0:
1497	return -ENOMEM;
1498}
1499EXPORT_SYMBOL_GPL(snmp_mib_init);
1500
1501void snmp_mib_free(void __percpu *ptr[2])
1502{
1503	BUG_ON(ptr == NULL);
1504	free_percpu(ptr[0]);
1505	free_percpu(ptr[1]);
1506	ptr[0] = ptr[1] = NULL;
1507}
1508EXPORT_SYMBOL_GPL(snmp_mib_free);
1509
1510#ifdef CONFIG_IP_MULTICAST
1511static const struct net_protocol igmp_protocol = {
1512	.handler =	igmp_rcv,
1513	.netns_ok =	1,
1514};
1515#endif
1516
1517static const struct net_protocol tcp_protocol = {
1518	.handler =	tcp_v4_rcv,
1519	.err_handler =	tcp_v4_err,
1520	.gso_send_check = tcp_v4_gso_send_check,
1521	.gso_segment =	tcp_tso_segment,
1522	.gro_receive =	tcp4_gro_receive,
1523	.gro_complete =	tcp4_gro_complete,
1524	.no_policy =	1,
1525	.netns_ok =	1,
1526};
1527
1528static const struct net_protocol udp_protocol = {
1529	.handler =	udp_rcv,
1530	.err_handler =	udp_err,
1531	.gso_send_check = udp4_ufo_send_check,
1532	.gso_segment = udp4_ufo_fragment,
1533	.no_policy =	1,
1534	.netns_ok =	1,
1535};
1536
1537static const struct net_protocol icmp_protocol = {
1538	.handler =	icmp_rcv,
1539	.err_handler =	ping_err,
1540	.no_policy =	1,
1541	.netns_ok =	1,
1542};
1543
1544static __net_init int ipv4_mib_init_net(struct net *net)
1545{
1546	if (snmp_mib_init((void __percpu **)net->mib.tcp_statistics,
1547			  sizeof(struct tcp_mib),
1548			  __alignof__(struct tcp_mib)) < 0)
1549		goto err_tcp_mib;
1550	if (snmp_mib_init((void __percpu **)net->mib.ip_statistics,
1551			  sizeof(struct ipstats_mib),
1552			  __alignof__(struct ipstats_mib)) < 0)
1553		goto err_ip_mib;
1554	if (snmp_mib_init((void __percpu **)net->mib.net_statistics,
1555			  sizeof(struct linux_mib),
1556			  __alignof__(struct linux_mib)) < 0)
1557		goto err_net_mib;
1558	if (snmp_mib_init((void __percpu **)net->mib.udp_statistics,
1559			  sizeof(struct udp_mib),
1560			  __alignof__(struct udp_mib)) < 0)
1561		goto err_udp_mib;
1562	if (snmp_mib_init((void __percpu **)net->mib.udplite_statistics,
1563			  sizeof(struct udp_mib),
1564			  __alignof__(struct udp_mib)) < 0)
1565		goto err_udplite_mib;
1566	if (snmp_mib_init((void __percpu **)net->mib.icmp_statistics,
1567			  sizeof(struct icmp_mib),
1568			  __alignof__(struct icmp_mib)) < 0)
1569		goto err_icmp_mib;
1570	if (snmp_mib_init((void __percpu **)net->mib.icmpmsg_statistics,
1571			  sizeof(struct icmpmsg_mib),
1572			  __alignof__(struct icmpmsg_mib)) < 0)
1573		goto err_icmpmsg_mib;
1574
1575	tcp_mib_init(net);
1576	return 0;
1577
1578err_icmpmsg_mib:
1579	snmp_mib_free((void __percpu **)net->mib.icmp_statistics);
1580err_icmp_mib:
1581	snmp_mib_free((void __percpu **)net->mib.udplite_statistics);
1582err_udplite_mib:
1583	snmp_mib_free((void __percpu **)net->mib.udp_statistics);
1584err_udp_mib:
1585	snmp_mib_free((void __percpu **)net->mib.net_statistics);
1586err_net_mib:
1587	snmp_mib_free((void __percpu **)net->mib.ip_statistics);
1588err_ip_mib:
1589	snmp_mib_free((void __percpu **)net->mib.tcp_statistics);
1590err_tcp_mib:
1591	return -ENOMEM;
1592}
1593
1594static __net_exit void ipv4_mib_exit_net(struct net *net)
1595{
1596	snmp_mib_free((void __percpu **)net->mib.icmpmsg_statistics);
1597	snmp_mib_free((void __percpu **)net->mib.icmp_statistics);
1598	snmp_mib_free((void __percpu **)net->mib.udplite_statistics);
1599	snmp_mib_free((void __percpu **)net->mib.udp_statistics);
1600	snmp_mib_free((void __percpu **)net->mib.net_statistics);
1601	snmp_mib_free((void __percpu **)net->mib.ip_statistics);
1602	snmp_mib_free((void __percpu **)net->mib.tcp_statistics);
1603}
1604
1605static __net_initdata struct pernet_operations ipv4_mib_ops = {
1606	.init = ipv4_mib_init_net,
1607	.exit = ipv4_mib_exit_net,
1608};
1609
1610static int __init init_ipv4_mibs(void)
1611{
1612	return register_pernet_subsys(&ipv4_mib_ops);
1613}
1614
1615static int ipv4_proc_init(void);
1616
1617/*
1618 *	IP protocol layer initialiser
1619 */
1620
1621static struct packet_type ip_packet_type __read_mostly = {
1622	.type = cpu_to_be16(ETH_P_IP),
1623	.func = ip_rcv,
1624	.gso_send_check = inet_gso_send_check,
1625	.gso_segment = inet_gso_segment,
1626	.gro_receive = inet_gro_receive,
1627	.gro_complete = inet_gro_complete,
1628};
1629
1630static int __init inet_init(void)
1631{
1632	struct sk_buff *dummy_skb;
1633	struct inet_protosw *q;
1634	struct list_head *r;
1635	int rc = -EINVAL;
1636
1637	BUILD_BUG_ON(sizeof(struct inet_skb_parm) > sizeof(dummy_skb->cb));
1638
1639	sysctl_local_reserved_ports = kzalloc(65536 / 8, GFP_KERNEL);
1640	if (!sysctl_local_reserved_ports)
1641		goto out;
1642
1643	rc = proto_register(&tcp_prot, 1);
1644	if (rc)
1645		goto out_free_reserved_ports;
1646
1647	rc = proto_register(&udp_prot, 1);
1648	if (rc)
1649		goto out_unregister_tcp_proto;
1650
1651	rc = proto_register(&raw_prot, 1);
1652	if (rc)
1653		goto out_unregister_udp_proto;
1654
1655	rc = proto_register(&ping_prot, 1);
1656	if (rc)
1657		goto out_unregister_raw_proto;
1658
1659	/*
1660	 *	Tell SOCKET that we are alive...
1661	 */
1662
1663	(void)sock_register(&inet_family_ops);
1664
1665#ifdef CONFIG_SYSCTL
1666	ip_static_sysctl_init();
1667#endif
1668
1669	/*
1670	 *	Add all the base protocols.
1671	 */
1672
1673	if (inet_add_protocol(&icmp_protocol, IPPROTO_ICMP) < 0)
1674		printk(KERN_CRIT "inet_init: Cannot add ICMP protocol\n");
1675	if (inet_add_protocol(&udp_protocol, IPPROTO_UDP) < 0)
1676		printk(KERN_CRIT "inet_init: Cannot add UDP protocol\n");
1677	if (inet_add_protocol(&tcp_protocol, IPPROTO_TCP) < 0)
1678		printk(KERN_CRIT "inet_init: Cannot add TCP protocol\n");
1679#ifdef CONFIG_IP_MULTICAST
1680	if (inet_add_protocol(&igmp_protocol, IPPROTO_IGMP) < 0)
1681		printk(KERN_CRIT "inet_init: Cannot add IGMP protocol\n");
1682#endif
1683
1684	/* Register the socket-side information for inet_create. */
1685	for (r = &inetsw[0]; r < &inetsw[SOCK_MAX]; ++r)
1686		INIT_LIST_HEAD(r);
1687
1688	for (q = inetsw_array; q < &inetsw_array[INETSW_ARRAY_LEN]; ++q)
1689		inet_register_protosw(q);
1690
1691	/*
1692	 *	Set the ARP module up
1693	 */
1694
1695	arp_init();
1696
1697	/*
1698	 *	Set the IP module up
1699	 */
1700
1701	ip_init();
1702
1703	tcp_v4_init();
1704
1705	/* Setup TCP slab cache for open requests. */
1706	tcp_init();
1707
1708	/* Setup UDP memory threshold */
1709	udp_init();
1710
1711	/* Add UDP-Lite (RFC 3828) */
1712	udplite4_register();
1713
1714	ping_init();
1715
1716	/*
1717	 *	Set the ICMP layer up
1718	 */
1719
1720	if (icmp_init() < 0)
1721		panic("Failed to create the ICMP control socket.\n");
1722
1723	/*
1724	 *	Initialise the multicast router
1725	 */
1726#if defined(CONFIG_IP_MROUTE)
1727	if (ip_mr_init())
1728		printk(KERN_CRIT "inet_init: Cannot init ipv4 mroute\n");
1729#endif
1730	/*
1731	 *	Initialise per-cpu ipv4 mibs
1732	 */
1733
1734	if (init_ipv4_mibs())
1735		printk(KERN_CRIT "inet_init: Cannot init ipv4 mibs\n");
1736
1737	ipv4_proc_init();
1738
1739	ipfrag_init();
1740
1741	dev_add_pack(&ip_packet_type);
1742
1743	rc = 0;
1744out:
1745	return rc;
1746out_unregister_raw_proto:
1747	proto_unregister(&raw_prot);
1748out_unregister_udp_proto:
1749	proto_unregister(&udp_prot);
1750out_unregister_tcp_proto:
1751	proto_unregister(&tcp_prot);
1752out_free_reserved_ports:
1753	kfree(sysctl_local_reserved_ports);
1754	goto out;
1755}
1756
1757fs_initcall(inet_init);
1758
1759/* ------------------------------------------------------------------------ */
1760
1761#ifdef CONFIG_PROC_FS
1762static int __init ipv4_proc_init(void)
1763{
1764	int rc = 0;
1765
1766	if (raw_proc_init())
1767		goto out_raw;
1768	if (tcp4_proc_init())
1769		goto out_tcp;
1770	if (udp4_proc_init())
1771		goto out_udp;
1772	if (ping_proc_init())
1773		goto out_ping;
1774	if (ip_misc_proc_init())
1775		goto out_misc;
1776out:
1777	return rc;
1778out_misc:
1779	ping_proc_exit();
1780out_ping:
1781	udp4_proc_exit();
1782out_udp:
1783	tcp4_proc_exit();
1784out_tcp:
1785	raw_proc_exit();
1786out_raw:
1787	rc = -ENOMEM;
1788	goto out;
1789}
1790
1791#else /* CONFIG_PROC_FS */
1792static int __init ipv4_proc_init(void)
1793{
1794	return 0;
1795}
1796#endif /* CONFIG_PROC_FS */
1797
1798MODULE_ALIAS_NETPROTO(PF_INET);
1799
1800