af_inet.c revision 2c804d0f8fc7799981d9fdd8c88653541b28c1a7
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#define pr_fmt(fmt) "IPv4: " fmt
69
70#include <linux/err.h>
71#include <linux/errno.h>
72#include <linux/types.h>
73#include <linux/socket.h>
74#include <linux/in.h>
75#include <linux/kernel.h>
76#include <linux/module.h>
77#include <linux/sched.h>
78#include <linux/timer.h>
79#include <linux/string.h>
80#include <linux/sockios.h>
81#include <linux/net.h>
82#include <linux/capability.h>
83#include <linux/fcntl.h>
84#include <linux/mm.h>
85#include <linux/interrupt.h>
86#include <linux/stat.h>
87#include <linux/init.h>
88#include <linux/poll.h>
89#include <linux/netfilter_ipv4.h>
90#include <linux/random.h>
91#include <linux/slab.h>
92
93#include <asm/uaccess.h>
94
95#include <linux/inet.h>
96#include <linux/igmp.h>
97#include <linux/inetdevice.h>
98#include <linux/netdevice.h>
99#include <net/checksum.h>
100#include <net/ip.h>
101#include <net/protocol.h>
102#include <net/arp.h>
103#include <net/route.h>
104#include <net/ip_fib.h>
105#include <net/inet_connection_sock.h>
106#include <net/tcp.h>
107#include <net/udp.h>
108#include <net/udplite.h>
109#include <net/ping.h>
110#include <linux/skbuff.h>
111#include <net/sock.h>
112#include <net/raw.h>
113#include <net/icmp.h>
114#include <net/inet_common.h>
115#include <net/xfrm.h>
116#include <net/net_namespace.h>
117#include <net/secure_seq.h>
118#ifdef CONFIG_IP_MROUTE
119#include <linux/mroute.h>
120#endif
121
122
123/* The inetsw table contains everything that inet_create needs to
124 * build a new socket.
125 */
126static struct list_head inetsw[SOCK_MAX];
127static DEFINE_SPINLOCK(inetsw_lock);
128
129/* New destruction routine */
130
131void inet_sock_destruct(struct sock *sk)
132{
133	struct inet_sock *inet = inet_sk(sk);
134
135	__skb_queue_purge(&sk->sk_receive_queue);
136	__skb_queue_purge(&sk->sk_error_queue);
137
138	sk_mem_reclaim(sk);
139
140	if (sk->sk_type == SOCK_STREAM && sk->sk_state != TCP_CLOSE) {
141		pr_err("Attempt to release TCP socket in state %d %p\n",
142		       sk->sk_state, sk);
143		return;
144	}
145	if (!sock_flag(sk, SOCK_DEAD)) {
146		pr_err("Attempt to release alive inet socket %p\n", sk);
147		return;
148	}
149
150	WARN_ON(atomic_read(&sk->sk_rmem_alloc));
151	WARN_ON(atomic_read(&sk->sk_wmem_alloc));
152	WARN_ON(sk->sk_wmem_queued);
153	WARN_ON(sk->sk_forward_alloc);
154
155	kfree(rcu_dereference_protected(inet->inet_opt, 1));
156	dst_release(rcu_dereference_check(sk->sk_dst_cache, 1));
157	dst_release(sk->sk_rx_dst);
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		/* Check special setups for testing purpose to enable TFO w/o
213		 * requiring TCP_FASTOPEN sockopt.
214		 * Note that only TCP sockets (SOCK_STREAM) will reach here.
215		 * Also fastopenq may already been allocated because this
216		 * socket was in TCP_LISTEN state previously but was
217		 * shutdown() (rather than close()).
218		 */
219		if ((sysctl_tcp_fastopen & TFO_SERVER_ENABLE) != 0 &&
220		    inet_csk(sk)->icsk_accept_queue.fastopenq == NULL) {
221			if ((sysctl_tcp_fastopen & TFO_SERVER_WO_SOCKOPT1) != 0)
222				err = fastopen_init_queue(sk, backlog);
223			else if ((sysctl_tcp_fastopen &
224				  TFO_SERVER_WO_SOCKOPT2) != 0)
225				err = fastopen_init_queue(sk,
226				    ((uint)sysctl_tcp_fastopen) >> 16);
227			else
228				err = 0;
229			if (err)
230				goto out;
231		}
232		err = inet_csk_listen_start(sk, backlog);
233		if (err)
234			goto out;
235	}
236	sk->sk_max_ack_backlog = backlog;
237	err = 0;
238
239out:
240	release_sock(sk);
241	return err;
242}
243EXPORT_SYMBOL(inet_listen);
244
245/*
246 *	Create an inet socket.
247 */
248
249static int inet_create(struct net *net, struct socket *sock, int protocol,
250		       int kern)
251{
252	struct sock *sk;
253	struct inet_protosw *answer;
254	struct inet_sock *inet;
255	struct proto *answer_prot;
256	unsigned char answer_flags;
257	int try_loading_module = 0;
258	int err;
259
260	sock->state = SS_UNCONNECTED;
261
262	/* Look for the requested type/protocol pair. */
263lookup_protocol:
264	err = -ESOCKTNOSUPPORT;
265	rcu_read_lock();
266	list_for_each_entry_rcu(answer, &inetsw[sock->type], list) {
267
268		err = 0;
269		/* Check the non-wild match. */
270		if (protocol == answer->protocol) {
271			if (protocol != IPPROTO_IP)
272				break;
273		} else {
274			/* Check for the two wild cases. */
275			if (IPPROTO_IP == protocol) {
276				protocol = answer->protocol;
277				break;
278			}
279			if (IPPROTO_IP == answer->protocol)
280				break;
281		}
282		err = -EPROTONOSUPPORT;
283	}
284
285	if (unlikely(err)) {
286		if (try_loading_module < 2) {
287			rcu_read_unlock();
288			/*
289			 * Be more specific, e.g. net-pf-2-proto-132-type-1
290			 * (net-pf-PF_INET-proto-IPPROTO_SCTP-type-SOCK_STREAM)
291			 */
292			if (++try_loading_module == 1)
293				request_module("net-pf-%d-proto-%d-type-%d",
294					       PF_INET, protocol, sock->type);
295			/*
296			 * Fall back to generic, e.g. net-pf-2-proto-132
297			 * (net-pf-PF_INET-proto-IPPROTO_SCTP)
298			 */
299			else
300				request_module("net-pf-%d-proto-%d",
301					       PF_INET, protocol);
302			goto lookup_protocol;
303		} else
304			goto out_rcu_unlock;
305	}
306
307	err = -EPERM;
308	if (sock->type == SOCK_RAW && !kern &&
309	    !ns_capable(net->user_ns, CAP_NET_RAW))
310		goto out_rcu_unlock;
311
312	sock->ops = answer->ops;
313	answer_prot = answer->prot;
314	answer_flags = answer->flags;
315	rcu_read_unlock();
316
317	WARN_ON(answer_prot->slab == NULL);
318
319	err = -ENOBUFS;
320	sk = sk_alloc(net, PF_INET, GFP_KERNEL, answer_prot);
321	if (sk == NULL)
322		goto out;
323
324	err = 0;
325	if (INET_PROTOSW_REUSE & answer_flags)
326		sk->sk_reuse = SK_CAN_REUSE;
327
328	inet = inet_sk(sk);
329	inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
330
331	inet->nodefrag = 0;
332
333	if (SOCK_RAW == sock->type) {
334		inet->inet_num = protocol;
335		if (IPPROTO_RAW == protocol)
336			inet->hdrincl = 1;
337	}
338
339	if (net->ipv4.sysctl_ip_no_pmtu_disc)
340		inet->pmtudisc = IP_PMTUDISC_DONT;
341	else
342		inet->pmtudisc = IP_PMTUDISC_WANT;
343
344	inet->inet_id = 0;
345
346	sock_init_data(sock, sk);
347
348	sk->sk_destruct	   = inet_sock_destruct;
349	sk->sk_protocol	   = protocol;
350	sk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
351
352	inet->uc_ttl	= -1;
353	inet->mc_loop	= 1;
354	inet->mc_ttl	= 1;
355	inet->mc_all	= 1;
356	inet->mc_index	= 0;
357	inet->mc_list	= NULL;
358	inet->rcv_tos	= 0;
359
360	sk_refcnt_debug_inc(sk);
361
362	if (inet->inet_num) {
363		/* It assumes that any protocol which allows
364		 * the user to assign a number at socket
365		 * creation time automatically
366		 * shares.
367		 */
368		inet->inet_sport = htons(inet->inet_num);
369		/* Add to protocol hash chains. */
370		sk->sk_prot->hash(sk);
371	}
372
373	if (sk->sk_prot->init) {
374		err = sk->sk_prot->init(sk);
375		if (err)
376			sk_common_release(sk);
377	}
378out:
379	return err;
380out_rcu_unlock:
381	rcu_read_unlock();
382	goto out;
383}
384
385
386/*
387 *	The peer socket should always be NULL (or else). When we call this
388 *	function we are destroying the object and from then on nobody
389 *	should refer to it.
390 */
391int inet_release(struct socket *sock)
392{
393	struct sock *sk = sock->sk;
394
395	if (sk) {
396		long timeout;
397
398		sock_rps_reset_flow(sk);
399
400		/* Applications forget to leave groups before exiting */
401		ip_mc_drop_socket(sk);
402
403		/* If linger is set, we don't return until the close
404		 * is complete.  Otherwise we return immediately. The
405		 * actually closing is done the same either way.
406		 *
407		 * If the close is due to the process exiting, we never
408		 * linger..
409		 */
410		timeout = 0;
411		if (sock_flag(sk, SOCK_LINGER) &&
412		    !(current->flags & PF_EXITING))
413			timeout = sk->sk_lingertime;
414		sock->sk = NULL;
415		sk->sk_prot->close(sk, timeout);
416	}
417	return 0;
418}
419EXPORT_SYMBOL(inet_release);
420
421int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
422{
423	struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
424	struct sock *sk = sock->sk;
425	struct inet_sock *inet = inet_sk(sk);
426	struct net *net = sock_net(sk);
427	unsigned short snum;
428	int chk_addr_ret;
429	int err;
430
431	/* If the socket has its own bind function then use it. (RAW) */
432	if (sk->sk_prot->bind) {
433		err = sk->sk_prot->bind(sk, uaddr, addr_len);
434		goto out;
435	}
436	err = -EINVAL;
437	if (addr_len < sizeof(struct sockaddr_in))
438		goto out;
439
440	if (addr->sin_family != AF_INET) {
441		/* Compatibility games : accept AF_UNSPEC (mapped to AF_INET)
442		 * only if s_addr is INADDR_ANY.
443		 */
444		err = -EAFNOSUPPORT;
445		if (addr->sin_family != AF_UNSPEC ||
446		    addr->sin_addr.s_addr != htonl(INADDR_ANY))
447			goto out;
448	}
449
450	chk_addr_ret = inet_addr_type(net, addr->sin_addr.s_addr);
451
452	/* Not specified by any standard per-se, however it breaks too
453	 * many applications when removed.  It is unfortunate since
454	 * allowing applications to make a non-local bind solves
455	 * several problems with systems using dynamic addressing.
456	 * (ie. your servers still start up even if your ISDN link
457	 *  is temporarily down)
458	 */
459	err = -EADDRNOTAVAIL;
460	if (!net->ipv4.sysctl_ip_nonlocal_bind &&
461	    !(inet->freebind || inet->transparent) &&
462	    addr->sin_addr.s_addr != htonl(INADDR_ANY) &&
463	    chk_addr_ret != RTN_LOCAL &&
464	    chk_addr_ret != RTN_MULTICAST &&
465	    chk_addr_ret != RTN_BROADCAST)
466		goto out;
467
468	snum = ntohs(addr->sin_port);
469	err = -EACCES;
470	if (snum && snum < PROT_SOCK &&
471	    !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE))
472		goto out;
473
474	/*      We keep a pair of addresses. rcv_saddr is the one
475	 *      used by hash lookups, and saddr is used for transmit.
476	 *
477	 *      In the BSD API these are the same except where it
478	 *      would be illegal to use them (multicast/broadcast) in
479	 *      which case the sending device address is used.
480	 */
481	lock_sock(sk);
482
483	/* Check these errors (active socket, double bind). */
484	err = -EINVAL;
485	if (sk->sk_state != TCP_CLOSE || inet->inet_num)
486		goto out_release_sock;
487
488	inet->inet_rcv_saddr = inet->inet_saddr = addr->sin_addr.s_addr;
489	if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST)
490		inet->inet_saddr = 0;  /* Use device */
491
492	/* Make sure we are allowed to bind here. */
493	if (sk->sk_prot->get_port(sk, snum)) {
494		inet->inet_saddr = inet->inet_rcv_saddr = 0;
495		err = -EADDRINUSE;
496		goto out_release_sock;
497	}
498
499	if (inet->inet_rcv_saddr)
500		sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
501	if (snum)
502		sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
503	inet->inet_sport = htons(inet->inet_num);
504	inet->inet_daddr = 0;
505	inet->inet_dport = 0;
506	sk_dst_reset(sk);
507	err = 0;
508out_release_sock:
509	release_sock(sk);
510out:
511	return err;
512}
513EXPORT_SYMBOL(inet_bind);
514
515int inet_dgram_connect(struct socket *sock, struct sockaddr *uaddr,
516		       int addr_len, int flags)
517{
518	struct sock *sk = sock->sk;
519
520	if (addr_len < sizeof(uaddr->sa_family))
521		return -EINVAL;
522	if (uaddr->sa_family == AF_UNSPEC)
523		return sk->sk_prot->disconnect(sk, flags);
524
525	if (!inet_sk(sk)->inet_num && inet_autobind(sk))
526		return -EAGAIN;
527	return sk->sk_prot->connect(sk, uaddr, addr_len);
528}
529EXPORT_SYMBOL(inet_dgram_connect);
530
531static long inet_wait_for_connect(struct sock *sk, long timeo, int writebias)
532{
533	DEFINE_WAIT(wait);
534
535	prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
536	sk->sk_write_pending += writebias;
537
538	/* Basic assumption: if someone sets sk->sk_err, he _must_
539	 * change state of the socket from TCP_SYN_*.
540	 * Connect() does not allow to get error notifications
541	 * without closing the socket.
542	 */
543	while ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
544		release_sock(sk);
545		timeo = schedule_timeout(timeo);
546		lock_sock(sk);
547		if (signal_pending(current) || !timeo)
548			break;
549		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
550	}
551	finish_wait(sk_sleep(sk), &wait);
552	sk->sk_write_pending -= writebias;
553	return timeo;
554}
555
556/*
557 *	Connect to a remote host. There is regrettably still a little
558 *	TCP 'magic' in here.
559 */
560int __inet_stream_connect(struct socket *sock, struct sockaddr *uaddr,
561			  int addr_len, int flags)
562{
563	struct sock *sk = sock->sk;
564	int err;
565	long timeo;
566
567	if (addr_len < sizeof(uaddr->sa_family))
568		return -EINVAL;
569
570	if (uaddr->sa_family == AF_UNSPEC) {
571		err = sk->sk_prot->disconnect(sk, flags);
572		sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
573		goto out;
574	}
575
576	switch (sock->state) {
577	default:
578		err = -EINVAL;
579		goto out;
580	case SS_CONNECTED:
581		err = -EISCONN;
582		goto out;
583	case SS_CONNECTING:
584		err = -EALREADY;
585		/* Fall out of switch with err, set for this state */
586		break;
587	case SS_UNCONNECTED:
588		err = -EISCONN;
589		if (sk->sk_state != TCP_CLOSE)
590			goto out;
591
592		err = sk->sk_prot->connect(sk, uaddr, addr_len);
593		if (err < 0)
594			goto out;
595
596		sock->state = SS_CONNECTING;
597
598		/* Just entered SS_CONNECTING state; the only
599		 * difference is that return value in non-blocking
600		 * case is EINPROGRESS, rather than EALREADY.
601		 */
602		err = -EINPROGRESS;
603		break;
604	}
605
606	timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
607
608	if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
609		int writebias = (sk->sk_protocol == IPPROTO_TCP) &&
610				tcp_sk(sk)->fastopen_req &&
611				tcp_sk(sk)->fastopen_req->data ? 1 : 0;
612
613		/* Error code is set above */
614		if (!timeo || !inet_wait_for_connect(sk, timeo, writebias))
615			goto out;
616
617		err = sock_intr_errno(timeo);
618		if (signal_pending(current))
619			goto out;
620	}
621
622	/* Connection was closed by RST, timeout, ICMP error
623	 * or another process disconnected us.
624	 */
625	if (sk->sk_state == TCP_CLOSE)
626		goto sock_error;
627
628	/* sk->sk_err may be not zero now, if RECVERR was ordered by user
629	 * and error was received after socket entered established state.
630	 * Hence, it is handled normally after connect() return successfully.
631	 */
632
633	sock->state = SS_CONNECTED;
634	err = 0;
635out:
636	return err;
637
638sock_error:
639	err = sock_error(sk) ? : -ECONNABORTED;
640	sock->state = SS_UNCONNECTED;
641	if (sk->sk_prot->disconnect(sk, flags))
642		sock->state = SS_DISCONNECTING;
643	goto out;
644}
645EXPORT_SYMBOL(__inet_stream_connect);
646
647int inet_stream_connect(struct socket *sock, struct sockaddr *uaddr,
648			int addr_len, int flags)
649{
650	int err;
651
652	lock_sock(sock->sk);
653	err = __inet_stream_connect(sock, uaddr, addr_len, flags);
654	release_sock(sock->sk);
655	return err;
656}
657EXPORT_SYMBOL(inet_stream_connect);
658
659/*
660 *	Accept a pending connection. The TCP layer now gives BSD semantics.
661 */
662
663int inet_accept(struct socket *sock, struct socket *newsock, int flags)
664{
665	struct sock *sk1 = sock->sk;
666	int err = -EINVAL;
667	struct sock *sk2 = sk1->sk_prot->accept(sk1, flags, &err);
668
669	if (!sk2)
670		goto do_err;
671
672	lock_sock(sk2);
673
674	sock_rps_record_flow(sk2);
675	WARN_ON(!((1 << sk2->sk_state) &
676		  (TCPF_ESTABLISHED | TCPF_SYN_RECV |
677		  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
885static int 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		.flags =      INET_PROTOSW_PERMANENT |
999			      INET_PROTOSW_ICSK,
1000	},
1001
1002	{
1003		.type =       SOCK_DGRAM,
1004		.protocol =   IPPROTO_UDP,
1005		.prot =       &udp_prot,
1006		.ops =        &inet_dgram_ops,
1007		.flags =      INET_PROTOSW_PERMANENT,
1008       },
1009
1010       {
1011		.type =       SOCK_DGRAM,
1012		.protocol =   IPPROTO_ICMP,
1013		.prot =       &ping_prot,
1014		.ops =        &inet_dgram_ops,
1015		.flags =      INET_PROTOSW_REUSE,
1016       },
1017
1018       {
1019	       .type =       SOCK_RAW,
1020	       .protocol =   IPPROTO_IP,	/* wild card */
1021	       .prot =       &raw_prot,
1022	       .ops =        &inet_sockraw_ops,
1023	       .flags =      INET_PROTOSW_REUSE,
1024       }
1025};
1026
1027#define INETSW_ARRAY_LEN ARRAY_SIZE(inetsw_array)
1028
1029void inet_register_protosw(struct inet_protosw *p)
1030{
1031	struct list_head *lh;
1032	struct inet_protosw *answer;
1033	int protocol = p->protocol;
1034	struct list_head *last_perm;
1035
1036	spin_lock_bh(&inetsw_lock);
1037
1038	if (p->type >= SOCK_MAX)
1039		goto out_illegal;
1040
1041	/* If we are trying to override a permanent protocol, bail. */
1042	answer = NULL;
1043	last_perm = &inetsw[p->type];
1044	list_for_each(lh, &inetsw[p->type]) {
1045		answer = list_entry(lh, struct inet_protosw, list);
1046
1047		/* Check only the non-wild match. */
1048		if (INET_PROTOSW_PERMANENT & answer->flags) {
1049			if (protocol == answer->protocol)
1050				break;
1051			last_perm = lh;
1052		}
1053
1054		answer = NULL;
1055	}
1056	if (answer)
1057		goto out_permanent;
1058
1059	/* Add the new entry after the last permanent entry if any, so that
1060	 * the new entry does not override a permanent entry when matched with
1061	 * a wild-card protocol. But it is allowed to override any existing
1062	 * non-permanent entry.  This means that when we remove this entry, the
1063	 * system automatically returns to the old behavior.
1064	 */
1065	list_add_rcu(&p->list, last_perm);
1066out:
1067	spin_unlock_bh(&inetsw_lock);
1068
1069	return;
1070
1071out_permanent:
1072	pr_err("Attempt to override permanent protocol %d\n", protocol);
1073	goto out;
1074
1075out_illegal:
1076	pr_err("Ignoring attempt to register invalid socket type %d\n",
1077	       p->type);
1078	goto out;
1079}
1080EXPORT_SYMBOL(inet_register_protosw);
1081
1082void inet_unregister_protosw(struct inet_protosw *p)
1083{
1084	if (INET_PROTOSW_PERMANENT & p->flags) {
1085		pr_err("Attempt to unregister permanent protocol %d\n",
1086		       p->protocol);
1087	} else {
1088		spin_lock_bh(&inetsw_lock);
1089		list_del_rcu(&p->list);
1090		spin_unlock_bh(&inetsw_lock);
1091
1092		synchronize_net();
1093	}
1094}
1095EXPORT_SYMBOL(inet_unregister_protosw);
1096
1097/*
1098 *      Shall we try to damage output packets if routing dev changes?
1099 */
1100
1101int sysctl_ip_dynaddr __read_mostly;
1102
1103static int inet_sk_reselect_saddr(struct sock *sk)
1104{
1105	struct inet_sock *inet = inet_sk(sk);
1106	__be32 old_saddr = inet->inet_saddr;
1107	__be32 daddr = inet->inet_daddr;
1108	struct flowi4 *fl4;
1109	struct rtable *rt;
1110	__be32 new_saddr;
1111	struct ip_options_rcu *inet_opt;
1112
1113	inet_opt = rcu_dereference_protected(inet->inet_opt,
1114					     sock_owned_by_user(sk));
1115	if (inet_opt && inet_opt->opt.srr)
1116		daddr = inet_opt->opt.faddr;
1117
1118	/* Query new route. */
1119	fl4 = &inet->cork.fl.u.ip4;
1120	rt = ip_route_connect(fl4, daddr, 0, RT_CONN_FLAGS(sk),
1121			      sk->sk_bound_dev_if, sk->sk_protocol,
1122			      inet->inet_sport, inet->inet_dport, sk);
1123	if (IS_ERR(rt))
1124		return PTR_ERR(rt);
1125
1126	sk_setup_caps(sk, &rt->dst);
1127
1128	new_saddr = fl4->saddr;
1129
1130	if (new_saddr == old_saddr)
1131		return 0;
1132
1133	if (sysctl_ip_dynaddr > 1) {
1134		pr_info("%s(): shifting inet->saddr from %pI4 to %pI4\n",
1135			__func__, &old_saddr, &new_saddr);
1136	}
1137
1138	inet->inet_saddr = inet->inet_rcv_saddr = new_saddr;
1139
1140	/*
1141	 * XXX The only one ugly spot where we need to
1142	 * XXX really change the sockets identity after
1143	 * XXX it has entered the hashes. -DaveM
1144	 *
1145	 * Besides that, it does not check for connection
1146	 * uniqueness. Wait for troubles.
1147	 */
1148	__sk_prot_rehash(sk);
1149	return 0;
1150}
1151
1152int inet_sk_rebuild_header(struct sock *sk)
1153{
1154	struct inet_sock *inet = inet_sk(sk);
1155	struct rtable *rt = (struct rtable *)__sk_dst_check(sk, 0);
1156	__be32 daddr;
1157	struct ip_options_rcu *inet_opt;
1158	struct flowi4 *fl4;
1159	int err;
1160
1161	/* Route is OK, nothing to do. */
1162	if (rt)
1163		return 0;
1164
1165	/* Reroute. */
1166	rcu_read_lock();
1167	inet_opt = rcu_dereference(inet->inet_opt);
1168	daddr = inet->inet_daddr;
1169	if (inet_opt && inet_opt->opt.srr)
1170		daddr = inet_opt->opt.faddr;
1171	rcu_read_unlock();
1172	fl4 = &inet->cork.fl.u.ip4;
1173	rt = ip_route_output_ports(sock_net(sk), fl4, sk, daddr, inet->inet_saddr,
1174				   inet->inet_dport, inet->inet_sport,
1175				   sk->sk_protocol, RT_CONN_FLAGS(sk),
1176				   sk->sk_bound_dev_if);
1177	if (!IS_ERR(rt)) {
1178		err = 0;
1179		sk_setup_caps(sk, &rt->dst);
1180	} else {
1181		err = PTR_ERR(rt);
1182
1183		/* Routing failed... */
1184		sk->sk_route_caps = 0;
1185		/*
1186		 * Other protocols have to map its equivalent state to TCP_SYN_SENT.
1187		 * DCCP maps its DCCP_REQUESTING state to TCP_SYN_SENT. -acme
1188		 */
1189		if (!sysctl_ip_dynaddr ||
1190		    sk->sk_state != TCP_SYN_SENT ||
1191		    (sk->sk_userlocks & SOCK_BINDADDR_LOCK) ||
1192		    (err = inet_sk_reselect_saddr(sk)) != 0)
1193			sk->sk_err_soft = -err;
1194	}
1195
1196	return err;
1197}
1198EXPORT_SYMBOL(inet_sk_rebuild_header);
1199
1200static struct sk_buff *inet_gso_segment(struct sk_buff *skb,
1201					netdev_features_t features)
1202{
1203	struct sk_buff *segs = ERR_PTR(-EINVAL);
1204	const struct net_offload *ops;
1205	unsigned int offset = 0;
1206	bool udpfrag, encap;
1207	struct iphdr *iph;
1208	int proto;
1209	int nhoff;
1210	int ihl;
1211	int id;
1212
1213	if (unlikely(skb_shinfo(skb)->gso_type &
1214		     ~(SKB_GSO_TCPV4 |
1215		       SKB_GSO_UDP |
1216		       SKB_GSO_DODGY |
1217		       SKB_GSO_TCP_ECN |
1218		       SKB_GSO_GRE |
1219		       SKB_GSO_GRE_CSUM |
1220		       SKB_GSO_IPIP |
1221		       SKB_GSO_SIT |
1222		       SKB_GSO_TCPV6 |
1223		       SKB_GSO_UDP_TUNNEL |
1224		       SKB_GSO_UDP_TUNNEL_CSUM |
1225		       SKB_GSO_MPLS |
1226		       0)))
1227		goto out;
1228
1229	skb_reset_network_header(skb);
1230	nhoff = skb_network_header(skb) - skb_mac_header(skb);
1231	if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
1232		goto out;
1233
1234	iph = ip_hdr(skb);
1235	ihl = iph->ihl * 4;
1236	if (ihl < sizeof(*iph))
1237		goto out;
1238
1239	id = ntohs(iph->id);
1240	proto = iph->protocol;
1241
1242	/* Warning: after this point, iph might be no longer valid */
1243	if (unlikely(!pskb_may_pull(skb, ihl)))
1244		goto out;
1245	__skb_pull(skb, ihl);
1246
1247	encap = SKB_GSO_CB(skb)->encap_level > 0;
1248	if (encap)
1249		features = skb->dev->hw_enc_features & netif_skb_features(skb);
1250	SKB_GSO_CB(skb)->encap_level += ihl;
1251
1252	skb_reset_transport_header(skb);
1253
1254	segs = ERR_PTR(-EPROTONOSUPPORT);
1255
1256	if (skb->encapsulation &&
1257	    skb_shinfo(skb)->gso_type & (SKB_GSO_SIT|SKB_GSO_IPIP))
1258		udpfrag = proto == IPPROTO_UDP && encap;
1259	else
1260		udpfrag = proto == IPPROTO_UDP && !skb->encapsulation;
1261
1262	ops = rcu_dereference(inet_offloads[proto]);
1263	if (likely(ops && ops->callbacks.gso_segment))
1264		segs = ops->callbacks.gso_segment(skb, features);
1265
1266	if (IS_ERR_OR_NULL(segs))
1267		goto out;
1268
1269	skb = segs;
1270	do {
1271		iph = (struct iphdr *)(skb_mac_header(skb) + nhoff);
1272		if (udpfrag) {
1273			iph->id = htons(id);
1274			iph->frag_off = htons(offset >> 3);
1275			if (skb->next != NULL)
1276				iph->frag_off |= htons(IP_MF);
1277			offset += skb->len - nhoff - ihl;
1278		} else {
1279			iph->id = htons(id++);
1280		}
1281		iph->tot_len = htons(skb->len - nhoff);
1282		ip_send_check(iph);
1283		if (encap)
1284			skb_reset_inner_headers(skb);
1285		skb->network_header = (u8 *)iph - skb->head;
1286	} while ((skb = skb->next));
1287
1288out:
1289	return segs;
1290}
1291
1292static struct sk_buff **inet_gro_receive(struct sk_buff **head,
1293					 struct sk_buff *skb)
1294{
1295	const struct net_offload *ops;
1296	struct sk_buff **pp = NULL;
1297	struct sk_buff *p;
1298	const struct iphdr *iph;
1299	unsigned int hlen;
1300	unsigned int off;
1301	unsigned int id;
1302	int flush = 1;
1303	int proto;
1304
1305	off = skb_gro_offset(skb);
1306	hlen = off + sizeof(*iph);
1307	iph = skb_gro_header_fast(skb, off);
1308	if (skb_gro_header_hard(skb, hlen)) {
1309		iph = skb_gro_header_slow(skb, hlen, off);
1310		if (unlikely(!iph))
1311			goto out;
1312	}
1313
1314	proto = iph->protocol;
1315
1316	rcu_read_lock();
1317	ops = rcu_dereference(inet_offloads[proto]);
1318	if (!ops || !ops->callbacks.gro_receive)
1319		goto out_unlock;
1320
1321	if (*(u8 *)iph != 0x45)
1322		goto out_unlock;
1323
1324	if (unlikely(ip_fast_csum((u8 *)iph, 5)))
1325		goto out_unlock;
1326
1327	id = ntohl(*(__be32 *)&iph->id);
1328	flush = (u16)((ntohl(*(__be32 *)iph) ^ skb_gro_len(skb)) | (id & ~IP_DF));
1329	id >>= 16;
1330
1331	for (p = *head; p; p = p->next) {
1332		struct iphdr *iph2;
1333
1334		if (!NAPI_GRO_CB(p)->same_flow)
1335			continue;
1336
1337		iph2 = (struct iphdr *)(p->data + off);
1338		/* The above works because, with the exception of the top
1339		 * (inner most) layer, we only aggregate pkts with the same
1340		 * hdr length so all the hdrs we'll need to verify will start
1341		 * at the same offset.
1342		 */
1343		if ((iph->protocol ^ iph2->protocol) |
1344		    ((__force u32)iph->saddr ^ (__force u32)iph2->saddr) |
1345		    ((__force u32)iph->daddr ^ (__force u32)iph2->daddr)) {
1346			NAPI_GRO_CB(p)->same_flow = 0;
1347			continue;
1348		}
1349
1350		/* All fields must match except length and checksum. */
1351		NAPI_GRO_CB(p)->flush |=
1352			(iph->ttl ^ iph2->ttl) |
1353			(iph->tos ^ iph2->tos) |
1354			((iph->frag_off ^ iph2->frag_off) & htons(IP_DF));
1355
1356		/* Save the IP ID check to be included later when we get to
1357		 * the transport layer so only the inner most IP ID is checked.
1358		 * This is because some GSO/TSO implementations do not
1359		 * correctly increment the IP ID for the outer hdrs.
1360		 */
1361		NAPI_GRO_CB(p)->flush_id =
1362			    ((u16)(ntohs(iph2->id) + NAPI_GRO_CB(p)->count) ^ id);
1363		NAPI_GRO_CB(p)->flush |= flush;
1364	}
1365
1366	NAPI_GRO_CB(skb)->flush |= flush;
1367	skb_set_network_header(skb, off);
1368	/* The above will be needed by the transport layer if there is one
1369	 * immediately following this IP hdr.
1370	 */
1371
1372	/* Note : No need to call skb_gro_postpull_rcsum() here,
1373	 * as we already checked checksum over ipv4 header was 0
1374	 */
1375	skb_gro_pull(skb, sizeof(*iph));
1376	skb_set_transport_header(skb, skb_gro_offset(skb));
1377
1378	pp = ops->callbacks.gro_receive(head, skb);
1379
1380out_unlock:
1381	rcu_read_unlock();
1382
1383out:
1384	NAPI_GRO_CB(skb)->flush |= flush;
1385
1386	return pp;
1387}
1388
1389static int inet_gro_complete(struct sk_buff *skb, int nhoff)
1390{
1391	__be16 newlen = htons(skb->len - nhoff);
1392	struct iphdr *iph = (struct iphdr *)(skb->data + nhoff);
1393	const struct net_offload *ops;
1394	int proto = iph->protocol;
1395	int err = -ENOSYS;
1396
1397	if (skb->encapsulation)
1398		skb_set_inner_network_header(skb, nhoff);
1399
1400	csum_replace2(&iph->check, iph->tot_len, newlen);
1401	iph->tot_len = newlen;
1402
1403	rcu_read_lock();
1404	ops = rcu_dereference(inet_offloads[proto]);
1405	if (WARN_ON(!ops || !ops->callbacks.gro_complete))
1406		goto out_unlock;
1407
1408	/* Only need to add sizeof(*iph) to get to the next hdr below
1409	 * because any hdr with option will have been flushed in
1410	 * inet_gro_receive().
1411	 */
1412	err = ops->callbacks.gro_complete(skb, nhoff + sizeof(*iph));
1413
1414out_unlock:
1415	rcu_read_unlock();
1416
1417	return err;
1418}
1419
1420int inet_ctl_sock_create(struct sock **sk, unsigned short family,
1421			 unsigned short type, unsigned char protocol,
1422			 struct net *net)
1423{
1424	struct socket *sock;
1425	int rc = sock_create_kern(family, type, protocol, &sock);
1426
1427	if (rc == 0) {
1428		*sk = sock->sk;
1429		(*sk)->sk_allocation = GFP_ATOMIC;
1430		/*
1431		 * Unhash it so that IP input processing does not even see it,
1432		 * we do not wish this socket to see incoming packets.
1433		 */
1434		(*sk)->sk_prot->unhash(*sk);
1435
1436		sk_change_net(*sk, net);
1437	}
1438	return rc;
1439}
1440EXPORT_SYMBOL_GPL(inet_ctl_sock_create);
1441
1442unsigned long snmp_fold_field(void __percpu *mib, int offt)
1443{
1444	unsigned long res = 0;
1445	int i;
1446
1447	for_each_possible_cpu(i)
1448		res += *(((unsigned long *) per_cpu_ptr(mib, i)) + offt);
1449	return res;
1450}
1451EXPORT_SYMBOL_GPL(snmp_fold_field);
1452
1453#if BITS_PER_LONG==32
1454
1455u64 snmp_fold_field64(void __percpu *mib, int offt, size_t syncp_offset)
1456{
1457	u64 res = 0;
1458	int cpu;
1459
1460	for_each_possible_cpu(cpu) {
1461		void *bhptr;
1462		struct u64_stats_sync *syncp;
1463		u64 v;
1464		unsigned int start;
1465
1466		bhptr = per_cpu_ptr(mib, cpu);
1467		syncp = (struct u64_stats_sync *)(bhptr + syncp_offset);
1468		do {
1469			start = u64_stats_fetch_begin_irq(syncp);
1470			v = *(((u64 *) bhptr) + offt);
1471		} while (u64_stats_fetch_retry_irq(syncp, start));
1472
1473		res += v;
1474	}
1475	return res;
1476}
1477EXPORT_SYMBOL_GPL(snmp_fold_field64);
1478#endif
1479
1480#ifdef CONFIG_IP_MULTICAST
1481static const struct net_protocol igmp_protocol = {
1482	.handler =	igmp_rcv,
1483	.netns_ok =	1,
1484};
1485#endif
1486
1487static const struct net_protocol tcp_protocol = {
1488	.early_demux	=	tcp_v4_early_demux,
1489	.handler	=	tcp_v4_rcv,
1490	.err_handler	=	tcp_v4_err,
1491	.no_policy	=	1,
1492	.netns_ok	=	1,
1493	.icmp_strict_tag_validation = 1,
1494};
1495
1496static const struct net_protocol udp_protocol = {
1497	.early_demux =	udp_v4_early_demux,
1498	.handler =	udp_rcv,
1499	.err_handler =	udp_err,
1500	.no_policy =	1,
1501	.netns_ok =	1,
1502};
1503
1504static const struct net_protocol icmp_protocol = {
1505	.handler =	icmp_rcv,
1506	.err_handler =	icmp_err,
1507	.no_policy =	1,
1508	.netns_ok =	1,
1509};
1510
1511static __net_init int ipv4_mib_init_net(struct net *net)
1512{
1513	int i;
1514
1515	net->mib.tcp_statistics = alloc_percpu(struct tcp_mib);
1516	if (!net->mib.tcp_statistics)
1517		goto err_tcp_mib;
1518	net->mib.ip_statistics = alloc_percpu(struct ipstats_mib);
1519	if (!net->mib.ip_statistics)
1520		goto err_ip_mib;
1521
1522	for_each_possible_cpu(i) {
1523		struct ipstats_mib *af_inet_stats;
1524		af_inet_stats = per_cpu_ptr(net->mib.ip_statistics, i);
1525		u64_stats_init(&af_inet_stats->syncp);
1526	}
1527
1528	net->mib.net_statistics = alloc_percpu(struct linux_mib);
1529	if (!net->mib.net_statistics)
1530		goto err_net_mib;
1531	net->mib.udp_statistics = alloc_percpu(struct udp_mib);
1532	if (!net->mib.udp_statistics)
1533		goto err_udp_mib;
1534	net->mib.udplite_statistics = alloc_percpu(struct udp_mib);
1535	if (!net->mib.udplite_statistics)
1536		goto err_udplite_mib;
1537	net->mib.icmp_statistics = alloc_percpu(struct icmp_mib);
1538	if (!net->mib.icmp_statistics)
1539		goto err_icmp_mib;
1540	net->mib.icmpmsg_statistics = kzalloc(sizeof(struct icmpmsg_mib),
1541					      GFP_KERNEL);
1542	if (!net->mib.icmpmsg_statistics)
1543		goto err_icmpmsg_mib;
1544
1545	tcp_mib_init(net);
1546	return 0;
1547
1548err_icmpmsg_mib:
1549	free_percpu(net->mib.icmp_statistics);
1550err_icmp_mib:
1551	free_percpu(net->mib.udplite_statistics);
1552err_udplite_mib:
1553	free_percpu(net->mib.udp_statistics);
1554err_udp_mib:
1555	free_percpu(net->mib.net_statistics);
1556err_net_mib:
1557	free_percpu(net->mib.ip_statistics);
1558err_ip_mib:
1559	free_percpu(net->mib.tcp_statistics);
1560err_tcp_mib:
1561	return -ENOMEM;
1562}
1563
1564static __net_exit void ipv4_mib_exit_net(struct net *net)
1565{
1566	kfree(net->mib.icmpmsg_statistics);
1567	free_percpu(net->mib.icmp_statistics);
1568	free_percpu(net->mib.udplite_statistics);
1569	free_percpu(net->mib.udp_statistics);
1570	free_percpu(net->mib.net_statistics);
1571	free_percpu(net->mib.ip_statistics);
1572	free_percpu(net->mib.tcp_statistics);
1573}
1574
1575static __net_initdata struct pernet_operations ipv4_mib_ops = {
1576	.init = ipv4_mib_init_net,
1577	.exit = ipv4_mib_exit_net,
1578};
1579
1580static int __init init_ipv4_mibs(void)
1581{
1582	return register_pernet_subsys(&ipv4_mib_ops);
1583}
1584
1585static __net_init int inet_init_net(struct net *net)
1586{
1587	/*
1588	 * Set defaults for local port range
1589	 */
1590	seqlock_init(&net->ipv4.ip_local_ports.lock);
1591	net->ipv4.ip_local_ports.range[0] =  32768;
1592	net->ipv4.ip_local_ports.range[1] =  61000;
1593
1594	seqlock_init(&net->ipv4.ping_group_range.lock);
1595	/*
1596	 * Sane defaults - nobody may create ping sockets.
1597	 * Boot scripts should set this to distro-specific group.
1598	 */
1599	net->ipv4.ping_group_range.range[0] = make_kgid(&init_user_ns, 1);
1600	net->ipv4.ping_group_range.range[1] = make_kgid(&init_user_ns, 0);
1601	return 0;
1602}
1603
1604static __net_exit void inet_exit_net(struct net *net)
1605{
1606}
1607
1608static __net_initdata struct pernet_operations af_inet_ops = {
1609	.init = inet_init_net,
1610	.exit = inet_exit_net,
1611};
1612
1613static int __init init_inet_pernet_ops(void)
1614{
1615	return register_pernet_subsys(&af_inet_ops);
1616}
1617
1618static int ipv4_proc_init(void);
1619
1620/*
1621 *	IP protocol layer initialiser
1622 */
1623
1624static struct packet_offload ip_packet_offload __read_mostly = {
1625	.type = cpu_to_be16(ETH_P_IP),
1626	.callbacks = {
1627		.gso_segment = inet_gso_segment,
1628		.gro_receive = inet_gro_receive,
1629		.gro_complete = inet_gro_complete,
1630	},
1631};
1632
1633static const struct net_offload ipip_offload = {
1634	.callbacks = {
1635		.gso_segment	= inet_gso_segment,
1636		.gro_receive	= inet_gro_receive,
1637		.gro_complete	= inet_gro_complete,
1638	},
1639};
1640
1641static int __init ipv4_offload_init(void)
1642{
1643	/*
1644	 * Add offloads
1645	 */
1646	if (udpv4_offload_init() < 0)
1647		pr_crit("%s: Cannot add UDP protocol offload\n", __func__);
1648	if (tcpv4_offload_init() < 0)
1649		pr_crit("%s: Cannot add TCP protocol offload\n", __func__);
1650
1651	dev_add_offload(&ip_packet_offload);
1652	inet_add_offload(&ipip_offload, IPPROTO_IPIP);
1653	return 0;
1654}
1655
1656fs_initcall(ipv4_offload_init);
1657
1658static struct packet_type ip_packet_type __read_mostly = {
1659	.type = cpu_to_be16(ETH_P_IP),
1660	.func = ip_rcv,
1661};
1662
1663static int __init inet_init(void)
1664{
1665	struct inet_protosw *q;
1666	struct list_head *r;
1667	int rc = -EINVAL;
1668
1669	BUILD_BUG_ON(sizeof(struct inet_skb_parm) > FIELD_SIZEOF(struct sk_buff, cb));
1670
1671	rc = proto_register(&tcp_prot, 1);
1672	if (rc)
1673		goto out;
1674
1675	rc = proto_register(&udp_prot, 1);
1676	if (rc)
1677		goto out_unregister_tcp_proto;
1678
1679	rc = proto_register(&raw_prot, 1);
1680	if (rc)
1681		goto out_unregister_udp_proto;
1682
1683	rc = proto_register(&ping_prot, 1);
1684	if (rc)
1685		goto out_unregister_raw_proto;
1686
1687	/*
1688	 *	Tell SOCKET that we are alive...
1689	 */
1690
1691	(void)sock_register(&inet_family_ops);
1692
1693#ifdef CONFIG_SYSCTL
1694	ip_static_sysctl_init();
1695#endif
1696
1697	/*
1698	 *	Add all the base protocols.
1699	 */
1700
1701	if (inet_add_protocol(&icmp_protocol, IPPROTO_ICMP) < 0)
1702		pr_crit("%s: Cannot add ICMP protocol\n", __func__);
1703	if (inet_add_protocol(&udp_protocol, IPPROTO_UDP) < 0)
1704		pr_crit("%s: Cannot add UDP protocol\n", __func__);
1705	if (inet_add_protocol(&tcp_protocol, IPPROTO_TCP) < 0)
1706		pr_crit("%s: Cannot add TCP protocol\n", __func__);
1707#ifdef CONFIG_IP_MULTICAST
1708	if (inet_add_protocol(&igmp_protocol, IPPROTO_IGMP) < 0)
1709		pr_crit("%s: Cannot add IGMP protocol\n", __func__);
1710#endif
1711
1712	/* Register the socket-side information for inet_create. */
1713	for (r = &inetsw[0]; r < &inetsw[SOCK_MAX]; ++r)
1714		INIT_LIST_HEAD(r);
1715
1716	for (q = inetsw_array; q < &inetsw_array[INETSW_ARRAY_LEN]; ++q)
1717		inet_register_protosw(q);
1718
1719	/*
1720	 *	Set the ARP module up
1721	 */
1722
1723	arp_init();
1724
1725	/*
1726	 *	Set the IP module up
1727	 */
1728
1729	ip_init();
1730
1731	tcp_v4_init();
1732
1733	/* Setup TCP slab cache for open requests. */
1734	tcp_init();
1735
1736	/* Setup UDP memory threshold */
1737	udp_init();
1738
1739	/* Add UDP-Lite (RFC 3828) */
1740	udplite4_register();
1741
1742	ping_init();
1743
1744	/*
1745	 *	Set the ICMP layer up
1746	 */
1747
1748	if (icmp_init() < 0)
1749		panic("Failed to create the ICMP control socket.\n");
1750
1751	/*
1752	 *	Initialise the multicast router
1753	 */
1754#if defined(CONFIG_IP_MROUTE)
1755	if (ip_mr_init())
1756		pr_crit("%s: Cannot init ipv4 mroute\n", __func__);
1757#endif
1758
1759	if (init_inet_pernet_ops())
1760		pr_crit("%s: Cannot init ipv4 inet pernet ops\n", __func__);
1761	/*
1762	 *	Initialise per-cpu ipv4 mibs
1763	 */
1764
1765	if (init_ipv4_mibs())
1766		pr_crit("%s: Cannot init ipv4 mibs\n", __func__);
1767
1768	ipv4_proc_init();
1769
1770	ipfrag_init();
1771
1772	dev_add_pack(&ip_packet_type);
1773
1774	rc = 0;
1775out:
1776	return rc;
1777out_unregister_raw_proto:
1778	proto_unregister(&raw_prot);
1779out_unregister_udp_proto:
1780	proto_unregister(&udp_prot);
1781out_unregister_tcp_proto:
1782	proto_unregister(&tcp_prot);
1783	goto out;
1784}
1785
1786fs_initcall(inet_init);
1787
1788/* ------------------------------------------------------------------------ */
1789
1790#ifdef CONFIG_PROC_FS
1791static int __init ipv4_proc_init(void)
1792{
1793	int rc = 0;
1794
1795	if (raw_proc_init())
1796		goto out_raw;
1797	if (tcp4_proc_init())
1798		goto out_tcp;
1799	if (udp4_proc_init())
1800		goto out_udp;
1801	if (ping_proc_init())
1802		goto out_ping;
1803	if (ip_misc_proc_init())
1804		goto out_misc;
1805out:
1806	return rc;
1807out_misc:
1808	ping_proc_exit();
1809out_ping:
1810	udp4_proc_exit();
1811out_udp:
1812	tcp4_proc_exit();
1813out_tcp:
1814	raw_proc_exit();
1815out_raw:
1816	rc = -ENOMEM;
1817	goto out;
1818}
1819
1820#else /* CONFIG_PROC_FS */
1821static int __init ipv4_proc_init(void)
1822{
1823	return 0;
1824}
1825#endif /* CONFIG_PROC_FS */
1826
1827MODULE_ALIAS_NETPROTO(PF_INET);
1828
1829