xref: /openbmc/linux/net/ipv4/af_inet.c (revision 367b8112)
1 /*
2  * INET		An implementation of the TCP/IP protocol suite for the LINUX
3  *		operating system.  INET is implemented using the  BSD Socket
4  *		interface as the means of communication with the user level.
5  *
6  *		PF_INET protocol family socket handler.
7  *
8  * Authors:	Ross Biro
9  *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
10  *		Florian La Roche, <flla@stud.uni-sb.de>
11  *		Alan Cox, <A.Cox@swansea.ac.uk>
12  *
13  * Changes (see also sock.c)
14  *
15  *		piggy,
16  *		Karl Knutson	:	Socket protocol table
17  *		A.N.Kuznetsov	:	Socket death error in accept().
18  *		John Richardson :	Fix non blocking error in connect()
19  *					so sockets that fail to connect
20  *					don't return -EINPROGRESS.
21  *		Alan Cox	:	Asynchronous I/O support
22  *		Alan Cox	:	Keep correct socket pointer on sock
23  *					structures
24  *					when accept() ed
25  *		Alan Cox	:	Semantics of SO_LINGER aren't state
26  *					moved to close when you look carefully.
27  *					With this fixed and the accept bug fixed
28  *					some RPC stuff seems happier.
29  *		Niibe Yutaka	:	4.4BSD style write async I/O
30  *		Alan Cox,
31  *		Tony Gale 	:	Fixed reuse semantics.
32  *		Alan Cox	:	bind() shouldn't abort existing but dead
33  *					sockets. Stops FTP netin:.. I hope.
34  *		Alan Cox	:	bind() works correctly for RAW sockets.
35  *					Note that FreeBSD at least was broken
36  *					in this respect so be careful with
37  *					compatibility tests...
38  *		Alan Cox	:	routing cache support
39  *		Alan Cox	:	memzero the socket structure for
40  *					compactness.
41  *		Matt Day	:	nonblock connect error handler
42  *		Alan Cox	:	Allow large numbers of pending sockets
43  *					(eg for big web sites), but only if
44  *					specifically application requested.
45  *		Alan Cox	:	New buffering throughout IP. Used
46  *					dumbly.
47  *		Alan Cox	:	New buffering now used smartly.
48  *		Alan Cox	:	BSD rather than common sense
49  *					interpretation of listen.
50  *		Germano Caronni	:	Assorted small races.
51  *		Alan Cox	:	sendmsg/recvmsg basic support.
52  *		Alan Cox	:	Only sendmsg/recvmsg now supported.
53  *		Alan Cox	:	Locked down bind (see security list).
54  *		Alan Cox	:	Loosened bind a little.
55  *		Mike McLagan	:	ADD/DEL DLCI Ioctls
56  *	Willy Konynenberg	:	Transparent proxying support.
57  *		David S. Miller	:	New socket lookup architecture.
58  *					Some other random speedups.
59  *		Cyrus Durgin	:	Cleaned up file for kmod hacks.
60  *		Andi Kleen	:	Fix inet_stream_connect TCP race.
61  *
62  *		This program is free software; you can redistribute it and/or
63  *		modify it under the terms of the GNU General Public License
64  *		as published by the Free Software Foundation; either version
65  *		2 of the License, or (at your option) any later version.
66  */
67 
68 #include <linux/err.h>
69 #include <linux/errno.h>
70 #include <linux/types.h>
71 #include <linux/socket.h>
72 #include <linux/in.h>
73 #include <linux/kernel.h>
74 #include <linux/module.h>
75 #include <linux/sched.h>
76 #include <linux/timer.h>
77 #include <linux/string.h>
78 #include <linux/sockios.h>
79 #include <linux/net.h>
80 #include <linux/capability.h>
81 #include <linux/fcntl.h>
82 #include <linux/mm.h>
83 #include <linux/interrupt.h>
84 #include <linux/stat.h>
85 #include <linux/init.h>
86 #include <linux/poll.h>
87 #include <linux/netfilter_ipv4.h>
88 #include <linux/random.h>
89 
90 #include <asm/uaccess.h>
91 #include <asm/system.h>
92 
93 #include <linux/inet.h>
94 #include <linux/igmp.h>
95 #include <linux/inetdevice.h>
96 #include <linux/netdevice.h>
97 #include <net/ip.h>
98 #include <net/protocol.h>
99 #include <net/arp.h>
100 #include <net/route.h>
101 #include <net/ip_fib.h>
102 #include <net/inet_connection_sock.h>
103 #include <net/tcp.h>
104 #include <net/udp.h>
105 #include <net/udplite.h>
106 #include <linux/skbuff.h>
107 #include <net/sock.h>
108 #include <net/raw.h>
109 #include <net/icmp.h>
110 #include <net/ipip.h>
111 #include <net/inet_common.h>
112 #include <net/xfrm.h>
113 #include <net/net_namespace.h>
114 #ifdef CONFIG_IP_MROUTE
115 #include <linux/mroute.h>
116 #endif
117 
118 extern void ip_mc_drop_socket(struct sock *sk);
119 
120 /* The inetsw table contains everything that inet_create needs to
121  * build a new socket.
122  */
123 static struct list_head inetsw[SOCK_MAX];
124 static DEFINE_SPINLOCK(inetsw_lock);
125 
126 struct ipv4_config ipv4_config;
127 
128 EXPORT_SYMBOL(ipv4_config);
129 
130 /* New destruction routine */
131 
132 void inet_sock_destruct(struct sock *sk)
133 {
134 	struct inet_sock *inet = inet_sk(sk);
135 
136 	__skb_queue_purge(&sk->sk_receive_queue);
137 	__skb_queue_purge(&sk->sk_error_queue);
138 
139 	sk_mem_reclaim(sk);
140 
141 	if (sk->sk_type == SOCK_STREAM && sk->sk_state != TCP_CLOSE) {
142 		printk("Attempt to release TCP socket in state %d %p\n",
143 		       sk->sk_state, sk);
144 		return;
145 	}
146 	if (!sock_flag(sk, SOCK_DEAD)) {
147 		printk("Attempt to release alive inet socket %p\n", sk);
148 		return;
149 	}
150 
151 	WARN_ON(atomic_read(&sk->sk_rmem_alloc));
152 	WARN_ON(atomic_read(&sk->sk_wmem_alloc));
153 	WARN_ON(sk->sk_wmem_queued);
154 	WARN_ON(sk->sk_forward_alloc);
155 
156 	kfree(inet->opt);
157 	dst_release(sk->sk_dst_cache);
158 	sk_refcnt_debug_dec(sk);
159 }
160 
161 /*
162  *	The routines beyond this point handle the behaviour of an AF_INET
163  *	socket object. Mostly it punts to the subprotocols of IP to do
164  *	the work.
165  */
166 
167 /*
168  *	Automatically bind an unbound socket.
169  */
170 
171 static int inet_autobind(struct sock *sk)
172 {
173 	struct inet_sock *inet;
174 	/* We may need to bind the socket. */
175 	lock_sock(sk);
176 	inet = inet_sk(sk);
177 	if (!inet->num) {
178 		if (sk->sk_prot->get_port(sk, 0)) {
179 			release_sock(sk);
180 			return -EAGAIN;
181 		}
182 		inet->sport = htons(inet->num);
183 	}
184 	release_sock(sk);
185 	return 0;
186 }
187 
188 /*
189  *	Move a socket into listening state.
190  */
191 int inet_listen(struct socket *sock, int backlog)
192 {
193 	struct sock *sk = sock->sk;
194 	unsigned char old_state;
195 	int err;
196 
197 	lock_sock(sk);
198 
199 	err = -EINVAL;
200 	if (sock->state != SS_UNCONNECTED || sock->type != SOCK_STREAM)
201 		goto out;
202 
203 	old_state = sk->sk_state;
204 	if (!((1 << old_state) & (TCPF_CLOSE | TCPF_LISTEN)))
205 		goto out;
206 
207 	/* Really, if the socket is already in listen state
208 	 * we can only allow the backlog to be adjusted.
209 	 */
210 	if (old_state != TCP_LISTEN) {
211 		err = inet_csk_listen_start(sk, backlog);
212 		if (err)
213 			goto out;
214 	}
215 	sk->sk_max_ack_backlog = backlog;
216 	err = 0;
217 
218 out:
219 	release_sock(sk);
220 	return err;
221 }
222 
223 u32 inet_ehash_secret __read_mostly;
224 EXPORT_SYMBOL(inet_ehash_secret);
225 
226 /*
227  * inet_ehash_secret must be set exactly once
228  * Instead of using a dedicated spinlock, we (ab)use inetsw_lock
229  */
230 void build_ehash_secret(void)
231 {
232 	u32 rnd;
233 	do {
234 		get_random_bytes(&rnd, sizeof(rnd));
235 	} while (rnd == 0);
236 	spin_lock_bh(&inetsw_lock);
237 	if (!inet_ehash_secret)
238 		inet_ehash_secret = rnd;
239 	spin_unlock_bh(&inetsw_lock);
240 }
241 EXPORT_SYMBOL(build_ehash_secret);
242 
243 static inline int inet_netns_ok(struct net *net, int protocol)
244 {
245 	int hash;
246 	struct net_protocol *ipprot;
247 
248 	if (net == &init_net)
249 		return 1;
250 
251 	hash = protocol & (MAX_INET_PROTOS - 1);
252 	ipprot = rcu_dereference(inet_protos[hash]);
253 
254 	if (ipprot == NULL)
255 		/* raw IP is OK */
256 		return 1;
257 	return ipprot->netns_ok;
258 }
259 
260 /*
261  *	Create an inet socket.
262  */
263 
264 static int inet_create(struct net *net, struct socket *sock, int protocol)
265 {
266 	struct sock *sk;
267 	struct inet_protosw *answer;
268 	struct inet_sock *inet;
269 	struct proto *answer_prot;
270 	unsigned char answer_flags;
271 	char answer_no_check;
272 	int try_loading_module = 0;
273 	int err;
274 
275 	if (sock->type != SOCK_RAW &&
276 	    sock->type != SOCK_DGRAM &&
277 	    !inet_ehash_secret)
278 		build_ehash_secret();
279 
280 	sock->state = SS_UNCONNECTED;
281 
282 	/* Look for the requested type/protocol pair. */
283 lookup_protocol:
284 	err = -ESOCKTNOSUPPORT;
285 	rcu_read_lock();
286 	list_for_each_entry_rcu(answer, &inetsw[sock->type], list) {
287 
288 		err = 0;
289 		/* Check the non-wild match. */
290 		if (protocol == answer->protocol) {
291 			if (protocol != IPPROTO_IP)
292 				break;
293 		} else {
294 			/* Check for the two wild cases. */
295 			if (IPPROTO_IP == protocol) {
296 				protocol = answer->protocol;
297 				break;
298 			}
299 			if (IPPROTO_IP == answer->protocol)
300 				break;
301 		}
302 		err = -EPROTONOSUPPORT;
303 	}
304 
305 	if (unlikely(err)) {
306 		if (try_loading_module < 2) {
307 			rcu_read_unlock();
308 			/*
309 			 * Be more specific, e.g. net-pf-2-proto-132-type-1
310 			 * (net-pf-PF_INET-proto-IPPROTO_SCTP-type-SOCK_STREAM)
311 			 */
312 			if (++try_loading_module == 1)
313 				request_module("net-pf-%d-proto-%d-type-%d",
314 					       PF_INET, protocol, sock->type);
315 			/*
316 			 * Fall back to generic, e.g. net-pf-2-proto-132
317 			 * (net-pf-PF_INET-proto-IPPROTO_SCTP)
318 			 */
319 			else
320 				request_module("net-pf-%d-proto-%d",
321 					       PF_INET, protocol);
322 			goto lookup_protocol;
323 		} else
324 			goto out_rcu_unlock;
325 	}
326 
327 	err = -EPERM;
328 	if (answer->capability > 0 && !capable(answer->capability))
329 		goto out_rcu_unlock;
330 
331 	err = -EAFNOSUPPORT;
332 	if (!inet_netns_ok(net, protocol))
333 		goto out_rcu_unlock;
334 
335 	sock->ops = answer->ops;
336 	answer_prot = answer->prot;
337 	answer_no_check = answer->no_check;
338 	answer_flags = answer->flags;
339 	rcu_read_unlock();
340 
341 	WARN_ON(answer_prot->slab == NULL);
342 
343 	err = -ENOBUFS;
344 	sk = sk_alloc(net, PF_INET, GFP_KERNEL, answer_prot);
345 	if (sk == NULL)
346 		goto out;
347 
348 	err = 0;
349 	sk->sk_no_check = answer_no_check;
350 	if (INET_PROTOSW_REUSE & answer_flags)
351 		sk->sk_reuse = 1;
352 
353 	inet = inet_sk(sk);
354 	inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
355 
356 	if (SOCK_RAW == sock->type) {
357 		inet->num = protocol;
358 		if (IPPROTO_RAW == protocol)
359 			inet->hdrincl = 1;
360 	}
361 
362 	if (ipv4_config.no_pmtu_disc)
363 		inet->pmtudisc = IP_PMTUDISC_DONT;
364 	else
365 		inet->pmtudisc = IP_PMTUDISC_WANT;
366 
367 	inet->id = 0;
368 
369 	sock_init_data(sock, sk);
370 
371 	sk->sk_destruct	   = inet_sock_destruct;
372 	sk->sk_family	   = PF_INET;
373 	sk->sk_protocol	   = protocol;
374 	sk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
375 
376 	inet->uc_ttl	= -1;
377 	inet->mc_loop	= 1;
378 	inet->mc_ttl	= 1;
379 	inet->mc_index	= 0;
380 	inet->mc_list	= NULL;
381 
382 	sk_refcnt_debug_inc(sk);
383 
384 	if (inet->num) {
385 		/* It assumes that any protocol which allows
386 		 * the user to assign a number at socket
387 		 * creation time automatically
388 		 * shares.
389 		 */
390 		inet->sport = htons(inet->num);
391 		/* Add to protocol hash chains. */
392 		sk->sk_prot->hash(sk);
393 	}
394 
395 	if (sk->sk_prot->init) {
396 		err = sk->sk_prot->init(sk);
397 		if (err)
398 			sk_common_release(sk);
399 	}
400 out:
401 	return err;
402 out_rcu_unlock:
403 	rcu_read_unlock();
404 	goto out;
405 }
406 
407 
408 /*
409  *	The peer socket should always be NULL (or else). When we call this
410  *	function we are destroying the object and from then on nobody
411  *	should refer to it.
412  */
413 int inet_release(struct socket *sock)
414 {
415 	struct sock *sk = sock->sk;
416 
417 	if (sk) {
418 		long timeout;
419 
420 		/* Applications forget to leave groups before exiting */
421 		ip_mc_drop_socket(sk);
422 
423 		/* If linger is set, we don't return until the close
424 		 * is complete.  Otherwise we return immediately. The
425 		 * actually closing is done the same either way.
426 		 *
427 		 * If the close is due to the process exiting, we never
428 		 * linger..
429 		 */
430 		timeout = 0;
431 		if (sock_flag(sk, SOCK_LINGER) &&
432 		    !(current->flags & PF_EXITING))
433 			timeout = sk->sk_lingertime;
434 		sock->sk = NULL;
435 		sk->sk_prot->close(sk, timeout);
436 	}
437 	return 0;
438 }
439 
440 /* It is off by default, see below. */
441 int sysctl_ip_nonlocal_bind __read_mostly;
442 
443 int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
444 {
445 	struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
446 	struct sock *sk = sock->sk;
447 	struct inet_sock *inet = inet_sk(sk);
448 	unsigned short snum;
449 	int chk_addr_ret;
450 	int err;
451 
452 	/* If the socket has its own bind function then use it. (RAW) */
453 	if (sk->sk_prot->bind) {
454 		err = sk->sk_prot->bind(sk, uaddr, addr_len);
455 		goto out;
456 	}
457 	err = -EINVAL;
458 	if (addr_len < sizeof(struct sockaddr_in))
459 		goto out;
460 
461 	chk_addr_ret = inet_addr_type(sock_net(sk), addr->sin_addr.s_addr);
462 
463 	/* Not specified by any standard per-se, however it breaks too
464 	 * many applications when removed.  It is unfortunate since
465 	 * allowing applications to make a non-local bind solves
466 	 * several problems with systems using dynamic addressing.
467 	 * (ie. your servers still start up even if your ISDN link
468 	 *  is temporarily down)
469 	 */
470 	err = -EADDRNOTAVAIL;
471 	if (!sysctl_ip_nonlocal_bind &&
472 	    !(inet->freebind || inet->transparent) &&
473 	    addr->sin_addr.s_addr != htonl(INADDR_ANY) &&
474 	    chk_addr_ret != RTN_LOCAL &&
475 	    chk_addr_ret != RTN_MULTICAST &&
476 	    chk_addr_ret != RTN_BROADCAST)
477 		goto out;
478 
479 	snum = ntohs(addr->sin_port);
480 	err = -EACCES;
481 	if (snum && snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
482 		goto out;
483 
484 	/*      We keep a pair of addresses. rcv_saddr is the one
485 	 *      used by hash lookups, and saddr is used for transmit.
486 	 *
487 	 *      In the BSD API these are the same except where it
488 	 *      would be illegal to use them (multicast/broadcast) in
489 	 *      which case the sending device address is used.
490 	 */
491 	lock_sock(sk);
492 
493 	/* Check these errors (active socket, double bind). */
494 	err = -EINVAL;
495 	if (sk->sk_state != TCP_CLOSE || inet->num)
496 		goto out_release_sock;
497 
498 	inet->rcv_saddr = inet->saddr = addr->sin_addr.s_addr;
499 	if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST)
500 		inet->saddr = 0;  /* Use device */
501 
502 	/* Make sure we are allowed to bind here. */
503 	if (sk->sk_prot->get_port(sk, snum)) {
504 		inet->saddr = inet->rcv_saddr = 0;
505 		err = -EADDRINUSE;
506 		goto out_release_sock;
507 	}
508 
509 	if (inet->rcv_saddr)
510 		sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
511 	if (snum)
512 		sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
513 	inet->sport = htons(inet->num);
514 	inet->daddr = 0;
515 	inet->dport = 0;
516 	sk_dst_reset(sk);
517 	err = 0;
518 out_release_sock:
519 	release_sock(sk);
520 out:
521 	return err;
522 }
523 
524 int inet_dgram_connect(struct socket *sock, struct sockaddr * uaddr,
525 		       int addr_len, int flags)
526 {
527 	struct sock *sk = sock->sk;
528 
529 	if (uaddr->sa_family == AF_UNSPEC)
530 		return sk->sk_prot->disconnect(sk, flags);
531 
532 	if (!inet_sk(sk)->num && inet_autobind(sk))
533 		return -EAGAIN;
534 	return sk->sk_prot->connect(sk, (struct sockaddr *)uaddr, addr_len);
535 }
536 
537 static long inet_wait_for_connect(struct sock *sk, long timeo)
538 {
539 	DEFINE_WAIT(wait);
540 
541 	prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
542 
543 	/* Basic assumption: if someone sets sk->sk_err, he _must_
544 	 * change state of the socket from TCP_SYN_*.
545 	 * Connect() does not allow to get error notifications
546 	 * without closing the socket.
547 	 */
548 	while ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
549 		release_sock(sk);
550 		timeo = schedule_timeout(timeo);
551 		lock_sock(sk);
552 		if (signal_pending(current) || !timeo)
553 			break;
554 		prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
555 	}
556 	finish_wait(sk->sk_sleep, &wait);
557 	return timeo;
558 }
559 
560 /*
561  *	Connect to a remote host. There is regrettably still a little
562  *	TCP 'magic' in here.
563  */
564 int inet_stream_connect(struct socket *sock, struct sockaddr *uaddr,
565 			int addr_len, int flags)
566 {
567 	struct sock *sk = sock->sk;
568 	int err;
569 	long timeo;
570 
571 	lock_sock(sk);
572 
573 	if (uaddr->sa_family == AF_UNSPEC) {
574 		err = sk->sk_prot->disconnect(sk, flags);
575 		sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
576 		goto out;
577 	}
578 
579 	switch (sock->state) {
580 	default:
581 		err = -EINVAL;
582 		goto out;
583 	case SS_CONNECTED:
584 		err = -EISCONN;
585 		goto out;
586 	case SS_CONNECTING:
587 		err = -EALREADY;
588 		/* Fall out of switch with err, set for this state */
589 		break;
590 	case SS_UNCONNECTED:
591 		err = -EISCONN;
592 		if (sk->sk_state != TCP_CLOSE)
593 			goto out;
594 
595 		err = sk->sk_prot->connect(sk, uaddr, addr_len);
596 		if (err < 0)
597 			goto out;
598 
599 		sock->state = SS_CONNECTING;
600 
601 		/* Just entered SS_CONNECTING state; the only
602 		 * difference is that return value in non-blocking
603 		 * case is EINPROGRESS, rather than EALREADY.
604 		 */
605 		err = -EINPROGRESS;
606 		break;
607 	}
608 
609 	timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
610 
611 	if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
612 		/* Error code is set above */
613 		if (!timeo || !inet_wait_for_connect(sk, timeo))
614 			goto out;
615 
616 		err = sock_intr_errno(timeo);
617 		if (signal_pending(current))
618 			goto out;
619 	}
620 
621 	/* Connection was closed by RST, timeout, ICMP error
622 	 * or another process disconnected us.
623 	 */
624 	if (sk->sk_state == TCP_CLOSE)
625 		goto sock_error;
626 
627 	/* sk->sk_err may be not zero now, if RECVERR was ordered by user
628 	 * and error was received after socket entered established state.
629 	 * Hence, it is handled normally after connect() return successfully.
630 	 */
631 
632 	sock->state = SS_CONNECTED;
633 	err = 0;
634 out:
635 	release_sock(sk);
636 	return err;
637 
638 sock_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 }
645 
646 /*
647  *	Accept a pending connection. The TCP layer now gives BSD semantics.
648  */
649 
650 int inet_accept(struct socket *sock, struct socket *newsock, int flags)
651 {
652 	struct sock *sk1 = sock->sk;
653 	int err = -EINVAL;
654 	struct sock *sk2 = sk1->sk_prot->accept(sk1, flags, &err);
655 
656 	if (!sk2)
657 		goto do_err;
658 
659 	lock_sock(sk2);
660 
661 	WARN_ON(!((1 << sk2->sk_state) &
662 		  (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT | TCPF_CLOSE)));
663 
664 	sock_graft(sk2, newsock);
665 
666 	newsock->state = SS_CONNECTED;
667 	err = 0;
668 	release_sock(sk2);
669 do_err:
670 	return err;
671 }
672 
673 
674 /*
675  *	This does both peername and sockname.
676  */
677 int inet_getname(struct socket *sock, struct sockaddr *uaddr,
678 			int *uaddr_len, int peer)
679 {
680 	struct sock *sk		= sock->sk;
681 	struct inet_sock *inet	= inet_sk(sk);
682 	struct sockaddr_in *sin	= (struct sockaddr_in *)uaddr;
683 
684 	sin->sin_family = AF_INET;
685 	if (peer) {
686 		if (!inet->dport ||
687 		    (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
688 		     peer == 1))
689 			return -ENOTCONN;
690 		sin->sin_port = inet->dport;
691 		sin->sin_addr.s_addr = inet->daddr;
692 	} else {
693 		__be32 addr = inet->rcv_saddr;
694 		if (!addr)
695 			addr = inet->saddr;
696 		sin->sin_port = inet->sport;
697 		sin->sin_addr.s_addr = addr;
698 	}
699 	memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
700 	*uaddr_len = sizeof(*sin);
701 	return 0;
702 }
703 
704 int inet_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
705 		 size_t size)
706 {
707 	struct sock *sk = sock->sk;
708 
709 	/* We may need to bind the socket. */
710 	if (!inet_sk(sk)->num && inet_autobind(sk))
711 		return -EAGAIN;
712 
713 	return sk->sk_prot->sendmsg(iocb, sk, msg, size);
714 }
715 
716 
717 static ssize_t inet_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
718 {
719 	struct sock *sk = sock->sk;
720 
721 	/* We may need to bind the socket. */
722 	if (!inet_sk(sk)->num && inet_autobind(sk))
723 		return -EAGAIN;
724 
725 	if (sk->sk_prot->sendpage)
726 		return sk->sk_prot->sendpage(sk, page, offset, size, flags);
727 	return sock_no_sendpage(sock, page, offset, size, flags);
728 }
729 
730 
731 int inet_shutdown(struct socket *sock, int how)
732 {
733 	struct sock *sk = sock->sk;
734 	int err = 0;
735 
736 	/* This should really check to make sure
737 	 * the socket is a TCP socket. (WHY AC...)
738 	 */
739 	how++; /* maps 0->1 has the advantage of making bit 1 rcvs and
740 		       1->2 bit 2 snds.
741 		       2->3 */
742 	if ((how & ~SHUTDOWN_MASK) || !how)	/* MAXINT->0 */
743 		return -EINVAL;
744 
745 	lock_sock(sk);
746 	if (sock->state == SS_CONNECTING) {
747 		if ((1 << sk->sk_state) &
748 		    (TCPF_SYN_SENT | TCPF_SYN_RECV | TCPF_CLOSE))
749 			sock->state = SS_DISCONNECTING;
750 		else
751 			sock->state = SS_CONNECTED;
752 	}
753 
754 	switch (sk->sk_state) {
755 	case TCP_CLOSE:
756 		err = -ENOTCONN;
757 		/* Hack to wake up other listeners, who can poll for
758 		   POLLHUP, even on eg. unconnected UDP sockets -- RR */
759 	default:
760 		sk->sk_shutdown |= how;
761 		if (sk->sk_prot->shutdown)
762 			sk->sk_prot->shutdown(sk, how);
763 		break;
764 
765 	/* Remaining two branches are temporary solution for missing
766 	 * close() in multithreaded environment. It is _not_ a good idea,
767 	 * but we have no choice until close() is repaired at VFS level.
768 	 */
769 	case TCP_LISTEN:
770 		if (!(how & RCV_SHUTDOWN))
771 			break;
772 		/* Fall through */
773 	case TCP_SYN_SENT:
774 		err = sk->sk_prot->disconnect(sk, O_NONBLOCK);
775 		sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
776 		break;
777 	}
778 
779 	/* Wake up anyone sleeping in poll. */
780 	sk->sk_state_change(sk);
781 	release_sock(sk);
782 	return err;
783 }
784 
785 /*
786  *	ioctl() calls you can issue on an INET socket. Most of these are
787  *	device configuration and stuff and very rarely used. Some ioctls
788  *	pass on to the socket itself.
789  *
790  *	NOTE: I like the idea of a module for the config stuff. ie ifconfig
791  *	loads the devconfigure module does its configuring and unloads it.
792  *	There's a good 20K of config code hanging around the kernel.
793  */
794 
795 int inet_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
796 {
797 	struct sock *sk = sock->sk;
798 	int err = 0;
799 	struct net *net = sock_net(sk);
800 
801 	switch (cmd) {
802 		case SIOCGSTAMP:
803 			err = sock_get_timestamp(sk, (struct timeval __user *)arg);
804 			break;
805 		case SIOCGSTAMPNS:
806 			err = sock_get_timestampns(sk, (struct timespec __user *)arg);
807 			break;
808 		case SIOCADDRT:
809 		case SIOCDELRT:
810 		case SIOCRTMSG:
811 			err = ip_rt_ioctl(net, cmd, (void __user *)arg);
812 			break;
813 		case SIOCDARP:
814 		case SIOCGARP:
815 		case SIOCSARP:
816 			err = arp_ioctl(net, cmd, (void __user *)arg);
817 			break;
818 		case SIOCGIFADDR:
819 		case SIOCSIFADDR:
820 		case SIOCGIFBRDADDR:
821 		case SIOCSIFBRDADDR:
822 		case SIOCGIFNETMASK:
823 		case SIOCSIFNETMASK:
824 		case SIOCGIFDSTADDR:
825 		case SIOCSIFDSTADDR:
826 		case SIOCSIFPFLAGS:
827 		case SIOCGIFPFLAGS:
828 		case SIOCSIFFLAGS:
829 			err = devinet_ioctl(net, cmd, (void __user *)arg);
830 			break;
831 		default:
832 			if (sk->sk_prot->ioctl)
833 				err = sk->sk_prot->ioctl(sk, cmd, arg);
834 			else
835 				err = -ENOIOCTLCMD;
836 			break;
837 	}
838 	return err;
839 }
840 
841 const struct proto_ops inet_stream_ops = {
842 	.family		   = PF_INET,
843 	.owner		   = THIS_MODULE,
844 	.release	   = inet_release,
845 	.bind		   = inet_bind,
846 	.connect	   = inet_stream_connect,
847 	.socketpair	   = sock_no_socketpair,
848 	.accept		   = inet_accept,
849 	.getname	   = inet_getname,
850 	.poll		   = tcp_poll,
851 	.ioctl		   = inet_ioctl,
852 	.listen		   = inet_listen,
853 	.shutdown	   = inet_shutdown,
854 	.setsockopt	   = sock_common_setsockopt,
855 	.getsockopt	   = sock_common_getsockopt,
856 	.sendmsg	   = tcp_sendmsg,
857 	.recvmsg	   = sock_common_recvmsg,
858 	.mmap		   = sock_no_mmap,
859 	.sendpage	   = tcp_sendpage,
860 	.splice_read	   = tcp_splice_read,
861 #ifdef CONFIG_COMPAT
862 	.compat_setsockopt = compat_sock_common_setsockopt,
863 	.compat_getsockopt = compat_sock_common_getsockopt,
864 #endif
865 };
866 
867 const struct proto_ops inet_dgram_ops = {
868 	.family		   = PF_INET,
869 	.owner		   = THIS_MODULE,
870 	.release	   = inet_release,
871 	.bind		   = inet_bind,
872 	.connect	   = inet_dgram_connect,
873 	.socketpair	   = sock_no_socketpair,
874 	.accept		   = sock_no_accept,
875 	.getname	   = inet_getname,
876 	.poll		   = udp_poll,
877 	.ioctl		   = inet_ioctl,
878 	.listen		   = sock_no_listen,
879 	.shutdown	   = inet_shutdown,
880 	.setsockopt	   = sock_common_setsockopt,
881 	.getsockopt	   = sock_common_getsockopt,
882 	.sendmsg	   = inet_sendmsg,
883 	.recvmsg	   = sock_common_recvmsg,
884 	.mmap		   = sock_no_mmap,
885 	.sendpage	   = inet_sendpage,
886 #ifdef CONFIG_COMPAT
887 	.compat_setsockopt = compat_sock_common_setsockopt,
888 	.compat_getsockopt = compat_sock_common_getsockopt,
889 #endif
890 };
891 
892 /*
893  * For SOCK_RAW sockets; should be the same as inet_dgram_ops but without
894  * udp_poll
895  */
896 static const struct proto_ops inet_sockraw_ops = {
897 	.family		   = PF_INET,
898 	.owner		   = THIS_MODULE,
899 	.release	   = inet_release,
900 	.bind		   = inet_bind,
901 	.connect	   = inet_dgram_connect,
902 	.socketpair	   = sock_no_socketpair,
903 	.accept		   = sock_no_accept,
904 	.getname	   = inet_getname,
905 	.poll		   = datagram_poll,
906 	.ioctl		   = inet_ioctl,
907 	.listen		   = sock_no_listen,
908 	.shutdown	   = inet_shutdown,
909 	.setsockopt	   = sock_common_setsockopt,
910 	.getsockopt	   = sock_common_getsockopt,
911 	.sendmsg	   = inet_sendmsg,
912 	.recvmsg	   = sock_common_recvmsg,
913 	.mmap		   = sock_no_mmap,
914 	.sendpage	   = inet_sendpage,
915 #ifdef CONFIG_COMPAT
916 	.compat_setsockopt = compat_sock_common_setsockopt,
917 	.compat_getsockopt = compat_sock_common_getsockopt,
918 #endif
919 };
920 
921 static struct net_proto_family inet_family_ops = {
922 	.family = PF_INET,
923 	.create = inet_create,
924 	.owner	= THIS_MODULE,
925 };
926 
927 /* Upon startup we insert all the elements in inetsw_array[] into
928  * the linked list inetsw.
929  */
930 static struct inet_protosw inetsw_array[] =
931 {
932 	{
933 		.type =       SOCK_STREAM,
934 		.protocol =   IPPROTO_TCP,
935 		.prot =       &tcp_prot,
936 		.ops =        &inet_stream_ops,
937 		.capability = -1,
938 		.no_check =   0,
939 		.flags =      INET_PROTOSW_PERMANENT |
940 			      INET_PROTOSW_ICSK,
941 	},
942 
943 	{
944 		.type =       SOCK_DGRAM,
945 		.protocol =   IPPROTO_UDP,
946 		.prot =       &udp_prot,
947 		.ops =        &inet_dgram_ops,
948 		.capability = -1,
949 		.no_check =   UDP_CSUM_DEFAULT,
950 		.flags =      INET_PROTOSW_PERMANENT,
951        },
952 
953 
954        {
955 	       .type =       SOCK_RAW,
956 	       .protocol =   IPPROTO_IP,	/* wild card */
957 	       .prot =       &raw_prot,
958 	       .ops =        &inet_sockraw_ops,
959 	       .capability = CAP_NET_RAW,
960 	       .no_check =   UDP_CSUM_DEFAULT,
961 	       .flags =      INET_PROTOSW_REUSE,
962        }
963 };
964 
965 #define INETSW_ARRAY_LEN ARRAY_SIZE(inetsw_array)
966 
967 void inet_register_protosw(struct inet_protosw *p)
968 {
969 	struct list_head *lh;
970 	struct inet_protosw *answer;
971 	int protocol = p->protocol;
972 	struct list_head *last_perm;
973 
974 	spin_lock_bh(&inetsw_lock);
975 
976 	if (p->type >= SOCK_MAX)
977 		goto out_illegal;
978 
979 	/* If we are trying to override a permanent protocol, bail. */
980 	answer = NULL;
981 	last_perm = &inetsw[p->type];
982 	list_for_each(lh, &inetsw[p->type]) {
983 		answer = list_entry(lh, struct inet_protosw, list);
984 
985 		/* Check only the non-wild match. */
986 		if (INET_PROTOSW_PERMANENT & answer->flags) {
987 			if (protocol == answer->protocol)
988 				break;
989 			last_perm = lh;
990 		}
991 
992 		answer = NULL;
993 	}
994 	if (answer)
995 		goto out_permanent;
996 
997 	/* Add the new entry after the last permanent entry if any, so that
998 	 * the new entry does not override a permanent entry when matched with
999 	 * a wild-card protocol. But it is allowed to override any existing
1000 	 * non-permanent entry.  This means that when we remove this entry, the
1001 	 * system automatically returns to the old behavior.
1002 	 */
1003 	list_add_rcu(&p->list, last_perm);
1004 out:
1005 	spin_unlock_bh(&inetsw_lock);
1006 
1007 	synchronize_net();
1008 
1009 	return;
1010 
1011 out_permanent:
1012 	printk(KERN_ERR "Attempt to override permanent protocol %d.\n",
1013 	       protocol);
1014 	goto out;
1015 
1016 out_illegal:
1017 	printk(KERN_ERR
1018 	       "Ignoring attempt to register invalid socket type %d.\n",
1019 	       p->type);
1020 	goto out;
1021 }
1022 
1023 void inet_unregister_protosw(struct inet_protosw *p)
1024 {
1025 	if (INET_PROTOSW_PERMANENT & p->flags) {
1026 		printk(KERN_ERR
1027 		       "Attempt to unregister permanent protocol %d.\n",
1028 		       p->protocol);
1029 	} else {
1030 		spin_lock_bh(&inetsw_lock);
1031 		list_del_rcu(&p->list);
1032 		spin_unlock_bh(&inetsw_lock);
1033 
1034 		synchronize_net();
1035 	}
1036 }
1037 
1038 /*
1039  *      Shall we try to damage output packets if routing dev changes?
1040  */
1041 
1042 int sysctl_ip_dynaddr __read_mostly;
1043 
1044 static int inet_sk_reselect_saddr(struct sock *sk)
1045 {
1046 	struct inet_sock *inet = inet_sk(sk);
1047 	int err;
1048 	struct rtable *rt;
1049 	__be32 old_saddr = inet->saddr;
1050 	__be32 new_saddr;
1051 	__be32 daddr = inet->daddr;
1052 
1053 	if (inet->opt && inet->opt->srr)
1054 		daddr = inet->opt->faddr;
1055 
1056 	/* Query new route. */
1057 	err = ip_route_connect(&rt, daddr, 0,
1058 			       RT_CONN_FLAGS(sk),
1059 			       sk->sk_bound_dev_if,
1060 			       sk->sk_protocol,
1061 			       inet->sport, inet->dport, sk, 0);
1062 	if (err)
1063 		return err;
1064 
1065 	sk_setup_caps(sk, &rt->u.dst);
1066 
1067 	new_saddr = rt->rt_src;
1068 
1069 	if (new_saddr == old_saddr)
1070 		return 0;
1071 
1072 	if (sysctl_ip_dynaddr > 1) {
1073 		printk(KERN_INFO "%s(): shifting inet->"
1074 				 "saddr from " NIPQUAD_FMT " to " NIPQUAD_FMT "\n",
1075 		       __func__,
1076 		       NIPQUAD(old_saddr),
1077 		       NIPQUAD(new_saddr));
1078 	}
1079 
1080 	inet->saddr = inet->rcv_saddr = new_saddr;
1081 
1082 	/*
1083 	 * XXX The only one ugly spot where we need to
1084 	 * XXX really change the sockets identity after
1085 	 * XXX it has entered the hashes. -DaveM
1086 	 *
1087 	 * Besides that, it does not check for connection
1088 	 * uniqueness. Wait for troubles.
1089 	 */
1090 	__sk_prot_rehash(sk);
1091 	return 0;
1092 }
1093 
1094 int inet_sk_rebuild_header(struct sock *sk)
1095 {
1096 	struct inet_sock *inet = inet_sk(sk);
1097 	struct rtable *rt = (struct rtable *)__sk_dst_check(sk, 0);
1098 	__be32 daddr;
1099 	int err;
1100 
1101 	/* Route is OK, nothing to do. */
1102 	if (rt)
1103 		return 0;
1104 
1105 	/* Reroute. */
1106 	daddr = inet->daddr;
1107 	if (inet->opt && inet->opt->srr)
1108 		daddr = inet->opt->faddr;
1109 {
1110 	struct flowi fl = {
1111 		.oif = sk->sk_bound_dev_if,
1112 		.nl_u = {
1113 			.ip4_u = {
1114 				.daddr	= daddr,
1115 				.saddr	= inet->saddr,
1116 				.tos	= RT_CONN_FLAGS(sk),
1117 			},
1118 		},
1119 		.proto = sk->sk_protocol,
1120 		.uli_u = {
1121 			.ports = {
1122 				.sport = inet->sport,
1123 				.dport = inet->dport,
1124 			},
1125 		},
1126 	};
1127 
1128 	security_sk_classify_flow(sk, &fl);
1129 	err = ip_route_output_flow(sock_net(sk), &rt, &fl, sk, 0);
1130 }
1131 	if (!err)
1132 		sk_setup_caps(sk, &rt->u.dst);
1133 	else {
1134 		/* Routing failed... */
1135 		sk->sk_route_caps = 0;
1136 		/*
1137 		 * Other protocols have to map its equivalent state to TCP_SYN_SENT.
1138 		 * DCCP maps its DCCP_REQUESTING state to TCP_SYN_SENT. -acme
1139 		 */
1140 		if (!sysctl_ip_dynaddr ||
1141 		    sk->sk_state != TCP_SYN_SENT ||
1142 		    (sk->sk_userlocks & SOCK_BINDADDR_LOCK) ||
1143 		    (err = inet_sk_reselect_saddr(sk)) != 0)
1144 			sk->sk_err_soft = -err;
1145 	}
1146 
1147 	return err;
1148 }
1149 
1150 EXPORT_SYMBOL(inet_sk_rebuild_header);
1151 
1152 static int inet_gso_send_check(struct sk_buff *skb)
1153 {
1154 	struct iphdr *iph;
1155 	struct net_protocol *ops;
1156 	int proto;
1157 	int ihl;
1158 	int err = -EINVAL;
1159 
1160 	if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
1161 		goto out;
1162 
1163 	iph = ip_hdr(skb);
1164 	ihl = iph->ihl * 4;
1165 	if (ihl < sizeof(*iph))
1166 		goto out;
1167 
1168 	if (unlikely(!pskb_may_pull(skb, ihl)))
1169 		goto out;
1170 
1171 	__skb_pull(skb, ihl);
1172 	skb_reset_transport_header(skb);
1173 	iph = ip_hdr(skb);
1174 	proto = iph->protocol & (MAX_INET_PROTOS - 1);
1175 	err = -EPROTONOSUPPORT;
1176 
1177 	rcu_read_lock();
1178 	ops = rcu_dereference(inet_protos[proto]);
1179 	if (likely(ops && ops->gso_send_check))
1180 		err = ops->gso_send_check(skb);
1181 	rcu_read_unlock();
1182 
1183 out:
1184 	return err;
1185 }
1186 
1187 static struct sk_buff *inet_gso_segment(struct sk_buff *skb, int features)
1188 {
1189 	struct sk_buff *segs = ERR_PTR(-EINVAL);
1190 	struct iphdr *iph;
1191 	struct net_protocol *ops;
1192 	int proto;
1193 	int ihl;
1194 	int id;
1195 
1196 	if (!(features & NETIF_F_V4_CSUM))
1197 		features &= ~NETIF_F_SG;
1198 
1199 	if (unlikely(skb_shinfo(skb)->gso_type &
1200 		     ~(SKB_GSO_TCPV4 |
1201 		       SKB_GSO_UDP |
1202 		       SKB_GSO_DODGY |
1203 		       SKB_GSO_TCP_ECN |
1204 		       0)))
1205 		goto out;
1206 
1207 	if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
1208 		goto out;
1209 
1210 	iph = ip_hdr(skb);
1211 	ihl = iph->ihl * 4;
1212 	if (ihl < sizeof(*iph))
1213 		goto out;
1214 
1215 	if (unlikely(!pskb_may_pull(skb, ihl)))
1216 		goto out;
1217 
1218 	__skb_pull(skb, ihl);
1219 	skb_reset_transport_header(skb);
1220 	iph = ip_hdr(skb);
1221 	id = ntohs(iph->id);
1222 	proto = iph->protocol & (MAX_INET_PROTOS - 1);
1223 	segs = ERR_PTR(-EPROTONOSUPPORT);
1224 
1225 	rcu_read_lock();
1226 	ops = rcu_dereference(inet_protos[proto]);
1227 	if (likely(ops && ops->gso_segment))
1228 		segs = ops->gso_segment(skb, features);
1229 	rcu_read_unlock();
1230 
1231 	if (!segs || IS_ERR(segs))
1232 		goto out;
1233 
1234 	skb = segs;
1235 	do {
1236 		iph = ip_hdr(skb);
1237 		iph->id = htons(id++);
1238 		iph->tot_len = htons(skb->len - skb->mac_len);
1239 		iph->check = 0;
1240 		iph->check = ip_fast_csum(skb_network_header(skb), iph->ihl);
1241 	} while ((skb = skb->next));
1242 
1243 out:
1244 	return segs;
1245 }
1246 
1247 int inet_ctl_sock_create(struct sock **sk, unsigned short family,
1248 			 unsigned short type, unsigned char protocol,
1249 			 struct net *net)
1250 {
1251 	struct socket *sock;
1252 	int rc = sock_create_kern(family, type, protocol, &sock);
1253 
1254 	if (rc == 0) {
1255 		*sk = sock->sk;
1256 		(*sk)->sk_allocation = GFP_ATOMIC;
1257 		/*
1258 		 * Unhash it so that IP input processing does not even see it,
1259 		 * we do not wish this socket to see incoming packets.
1260 		 */
1261 		(*sk)->sk_prot->unhash(*sk);
1262 
1263 		sk_change_net(*sk, net);
1264 	}
1265 	return rc;
1266 }
1267 
1268 EXPORT_SYMBOL_GPL(inet_ctl_sock_create);
1269 
1270 unsigned long snmp_fold_field(void *mib[], int offt)
1271 {
1272 	unsigned long res = 0;
1273 	int i;
1274 
1275 	for_each_possible_cpu(i) {
1276 		res += *(((unsigned long *) per_cpu_ptr(mib[0], i)) + offt);
1277 		res += *(((unsigned long *) per_cpu_ptr(mib[1], i)) + offt);
1278 	}
1279 	return res;
1280 }
1281 EXPORT_SYMBOL_GPL(snmp_fold_field);
1282 
1283 int snmp_mib_init(void *ptr[2], size_t mibsize)
1284 {
1285 	BUG_ON(ptr == NULL);
1286 	ptr[0] = __alloc_percpu(mibsize);
1287 	if (!ptr[0])
1288 		goto err0;
1289 	ptr[1] = __alloc_percpu(mibsize);
1290 	if (!ptr[1])
1291 		goto err1;
1292 	return 0;
1293 err1:
1294 	free_percpu(ptr[0]);
1295 	ptr[0] = NULL;
1296 err0:
1297 	return -ENOMEM;
1298 }
1299 EXPORT_SYMBOL_GPL(snmp_mib_init);
1300 
1301 void snmp_mib_free(void *ptr[2])
1302 {
1303 	BUG_ON(ptr == NULL);
1304 	free_percpu(ptr[0]);
1305 	free_percpu(ptr[1]);
1306 	ptr[0] = ptr[1] = NULL;
1307 }
1308 EXPORT_SYMBOL_GPL(snmp_mib_free);
1309 
1310 #ifdef CONFIG_IP_MULTICAST
1311 static struct net_protocol igmp_protocol = {
1312 	.handler =	igmp_rcv,
1313 };
1314 #endif
1315 
1316 static struct net_protocol tcp_protocol = {
1317 	.handler =	tcp_v4_rcv,
1318 	.err_handler =	tcp_v4_err,
1319 	.gso_send_check = tcp_v4_gso_send_check,
1320 	.gso_segment =	tcp_tso_segment,
1321 	.no_policy =	1,
1322 	.netns_ok =	1,
1323 };
1324 
1325 static struct net_protocol udp_protocol = {
1326 	.handler =	udp_rcv,
1327 	.err_handler =	udp_err,
1328 	.no_policy =	1,
1329 	.netns_ok =	1,
1330 };
1331 
1332 static struct net_protocol icmp_protocol = {
1333 	.handler =	icmp_rcv,
1334 	.no_policy =	1,
1335 	.netns_ok =	1,
1336 };
1337 
1338 static __net_init int ipv4_mib_init_net(struct net *net)
1339 {
1340 	if (snmp_mib_init((void **)net->mib.tcp_statistics,
1341 			  sizeof(struct tcp_mib)) < 0)
1342 		goto err_tcp_mib;
1343 	if (snmp_mib_init((void **)net->mib.ip_statistics,
1344 			  sizeof(struct ipstats_mib)) < 0)
1345 		goto err_ip_mib;
1346 	if (snmp_mib_init((void **)net->mib.net_statistics,
1347 			  sizeof(struct linux_mib)) < 0)
1348 		goto err_net_mib;
1349 	if (snmp_mib_init((void **)net->mib.udp_statistics,
1350 			  sizeof(struct udp_mib)) < 0)
1351 		goto err_udp_mib;
1352 	if (snmp_mib_init((void **)net->mib.udplite_statistics,
1353 			  sizeof(struct udp_mib)) < 0)
1354 		goto err_udplite_mib;
1355 	if (snmp_mib_init((void **)net->mib.icmp_statistics,
1356 			  sizeof(struct icmp_mib)) < 0)
1357 		goto err_icmp_mib;
1358 	if (snmp_mib_init((void **)net->mib.icmpmsg_statistics,
1359 			  sizeof(struct icmpmsg_mib)) < 0)
1360 		goto err_icmpmsg_mib;
1361 
1362 	tcp_mib_init(net);
1363 	return 0;
1364 
1365 err_icmpmsg_mib:
1366 	snmp_mib_free((void **)net->mib.icmp_statistics);
1367 err_icmp_mib:
1368 	snmp_mib_free((void **)net->mib.udplite_statistics);
1369 err_udplite_mib:
1370 	snmp_mib_free((void **)net->mib.udp_statistics);
1371 err_udp_mib:
1372 	snmp_mib_free((void **)net->mib.net_statistics);
1373 err_net_mib:
1374 	snmp_mib_free((void **)net->mib.ip_statistics);
1375 err_ip_mib:
1376 	snmp_mib_free((void **)net->mib.tcp_statistics);
1377 err_tcp_mib:
1378 	return -ENOMEM;
1379 }
1380 
1381 static __net_exit void ipv4_mib_exit_net(struct net *net)
1382 {
1383 	snmp_mib_free((void **)net->mib.icmpmsg_statistics);
1384 	snmp_mib_free((void **)net->mib.icmp_statistics);
1385 	snmp_mib_free((void **)net->mib.udplite_statistics);
1386 	snmp_mib_free((void **)net->mib.udp_statistics);
1387 	snmp_mib_free((void **)net->mib.net_statistics);
1388 	snmp_mib_free((void **)net->mib.ip_statistics);
1389 	snmp_mib_free((void **)net->mib.tcp_statistics);
1390 }
1391 
1392 static __net_initdata struct pernet_operations ipv4_mib_ops = {
1393 	.init = ipv4_mib_init_net,
1394 	.exit = ipv4_mib_exit_net,
1395 };
1396 
1397 static int __init init_ipv4_mibs(void)
1398 {
1399 	return register_pernet_subsys(&ipv4_mib_ops);
1400 }
1401 
1402 static int ipv4_proc_init(void);
1403 
1404 /*
1405  *	IP protocol layer initialiser
1406  */
1407 
1408 static struct packet_type ip_packet_type = {
1409 	.type = __constant_htons(ETH_P_IP),
1410 	.func = ip_rcv,
1411 	.gso_send_check = inet_gso_send_check,
1412 	.gso_segment = inet_gso_segment,
1413 };
1414 
1415 static int __init inet_init(void)
1416 {
1417 	struct sk_buff *dummy_skb;
1418 	struct inet_protosw *q;
1419 	struct list_head *r;
1420 	int rc = -EINVAL;
1421 
1422 	BUILD_BUG_ON(sizeof(struct inet_skb_parm) > sizeof(dummy_skb->cb));
1423 
1424 	rc = proto_register(&tcp_prot, 1);
1425 	if (rc)
1426 		goto out;
1427 
1428 	rc = proto_register(&udp_prot, 1);
1429 	if (rc)
1430 		goto out_unregister_tcp_proto;
1431 
1432 	rc = proto_register(&raw_prot, 1);
1433 	if (rc)
1434 		goto out_unregister_udp_proto;
1435 
1436 	/*
1437 	 *	Tell SOCKET that we are alive...
1438 	 */
1439 
1440 	(void)sock_register(&inet_family_ops);
1441 
1442 #ifdef CONFIG_SYSCTL
1443 	ip_static_sysctl_init();
1444 #endif
1445 
1446 	/*
1447 	 *	Add all the base protocols.
1448 	 */
1449 
1450 	if (inet_add_protocol(&icmp_protocol, IPPROTO_ICMP) < 0)
1451 		printk(KERN_CRIT "inet_init: Cannot add ICMP protocol\n");
1452 	if (inet_add_protocol(&udp_protocol, IPPROTO_UDP) < 0)
1453 		printk(KERN_CRIT "inet_init: Cannot add UDP protocol\n");
1454 	if (inet_add_protocol(&tcp_protocol, IPPROTO_TCP) < 0)
1455 		printk(KERN_CRIT "inet_init: Cannot add TCP protocol\n");
1456 #ifdef CONFIG_IP_MULTICAST
1457 	if (inet_add_protocol(&igmp_protocol, IPPROTO_IGMP) < 0)
1458 		printk(KERN_CRIT "inet_init: Cannot add IGMP protocol\n");
1459 #endif
1460 
1461 	/* Register the socket-side information for inet_create. */
1462 	for (r = &inetsw[0]; r < &inetsw[SOCK_MAX]; ++r)
1463 		INIT_LIST_HEAD(r);
1464 
1465 	for (q = inetsw_array; q < &inetsw_array[INETSW_ARRAY_LEN]; ++q)
1466 		inet_register_protosw(q);
1467 
1468 	/*
1469 	 *	Set the ARP module up
1470 	 */
1471 
1472 	arp_init();
1473 
1474 	/*
1475 	 *	Set the IP module up
1476 	 */
1477 
1478 	ip_init();
1479 
1480 	tcp_v4_init();
1481 
1482 	/* Setup TCP slab cache for open requests. */
1483 	tcp_init();
1484 
1485 	/* Setup UDP memory threshold */
1486 	udp_init();
1487 
1488 	/* Add UDP-Lite (RFC 3828) */
1489 	udplite4_register();
1490 
1491 	/*
1492 	 *	Set the ICMP layer up
1493 	 */
1494 
1495 	if (icmp_init() < 0)
1496 		panic("Failed to create the ICMP control socket.\n");
1497 
1498 	/*
1499 	 *	Initialise the multicast router
1500 	 */
1501 #if defined(CONFIG_IP_MROUTE)
1502 	if (ip_mr_init())
1503 		printk(KERN_CRIT "inet_init: Cannot init ipv4 mroute\n");
1504 #endif
1505 	/*
1506 	 *	Initialise per-cpu ipv4 mibs
1507 	 */
1508 
1509 	if (init_ipv4_mibs())
1510 		printk(KERN_CRIT "inet_init: Cannot init ipv4 mibs\n");
1511 
1512 	ipv4_proc_init();
1513 
1514 	ipfrag_init();
1515 
1516 	dev_add_pack(&ip_packet_type);
1517 
1518 	rc = 0;
1519 out:
1520 	return rc;
1521 out_unregister_udp_proto:
1522 	proto_unregister(&udp_prot);
1523 out_unregister_tcp_proto:
1524 	proto_unregister(&tcp_prot);
1525 	goto out;
1526 }
1527 
1528 fs_initcall(inet_init);
1529 
1530 /* ------------------------------------------------------------------------ */
1531 
1532 #ifdef CONFIG_PROC_FS
1533 static int __init ipv4_proc_init(void)
1534 {
1535 	int rc = 0;
1536 
1537 	if (raw_proc_init())
1538 		goto out_raw;
1539 	if (tcp4_proc_init())
1540 		goto out_tcp;
1541 	if (udp4_proc_init())
1542 		goto out_udp;
1543 	if (ip_misc_proc_init())
1544 		goto out_misc;
1545 out:
1546 	return rc;
1547 out_misc:
1548 	udp4_proc_exit();
1549 out_udp:
1550 	tcp4_proc_exit();
1551 out_tcp:
1552 	raw_proc_exit();
1553 out_raw:
1554 	rc = -ENOMEM;
1555 	goto out;
1556 }
1557 
1558 #else /* CONFIG_PROC_FS */
1559 static int __init ipv4_proc_init(void)
1560 {
1561 	return 0;
1562 }
1563 #endif /* CONFIG_PROC_FS */
1564 
1565 MODULE_ALIAS_NETPROTO(PF_INET);
1566 
1567 EXPORT_SYMBOL(inet_accept);
1568 EXPORT_SYMBOL(inet_bind);
1569 EXPORT_SYMBOL(inet_dgram_connect);
1570 EXPORT_SYMBOL(inet_dgram_ops);
1571 EXPORT_SYMBOL(inet_getname);
1572 EXPORT_SYMBOL(inet_ioctl);
1573 EXPORT_SYMBOL(inet_listen);
1574 EXPORT_SYMBOL(inet_register_protosw);
1575 EXPORT_SYMBOL(inet_release);
1576 EXPORT_SYMBOL(inet_sendmsg);
1577 EXPORT_SYMBOL(inet_shutdown);
1578 EXPORT_SYMBOL(inet_sock_destruct);
1579 EXPORT_SYMBOL(inet_stream_connect);
1580 EXPORT_SYMBOL(inet_stream_ops);
1581 EXPORT_SYMBOL(inet_unregister_protosw);
1582 EXPORT_SYMBOL(sysctl_ip_nonlocal_bind);
1583