af_inet.c 39.8 KB
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/*
 * INET		An implementation of the TCP/IP protocol suite for the LINUX
 *		operating system.  INET is implemented using the  BSD Socket
 *		interface as the means of communication with the user level.
 *
 *		PF_INET protocol family socket handler.
 *
8
 * Authors:	Ross Biro
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 *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
 *		Florian La Roche, <flla@stud.uni-sb.de>
 *		Alan Cox, <A.Cox@swansea.ac.uk>
 *
 * Changes (see also sock.c)
 *
 *		piggy,
 *		Karl Knutson	:	Socket protocol table
 *		A.N.Kuznetsov	:	Socket death error in accept().
 *		John Richardson :	Fix non blocking error in connect()
 *					so sockets that fail to connect
 *					don't return -EINPROGRESS.
 *		Alan Cox	:	Asynchronous I/O support
 *		Alan Cox	:	Keep correct socket pointer on sock
 *					structures
 *					when accept() ed
 *		Alan Cox	:	Semantics of SO_LINGER aren't state
 *					moved to close when you look carefully.
 *					With this fixed and the accept bug fixed
 *					some RPC stuff seems happier.
 *		Niibe Yutaka	:	4.4BSD style write async I/O
 *		Alan Cox,
 *		Tony Gale 	:	Fixed reuse semantics.
 *		Alan Cox	:	bind() shouldn't abort existing but dead
 *					sockets. Stops FTP netin:.. I hope.
 *		Alan Cox	:	bind() works correctly for RAW sockets.
 *					Note that FreeBSD at least was broken
 *					in this respect so be careful with
 *					compatibility tests...
 *		Alan Cox	:	routing cache support
 *		Alan Cox	:	memzero the socket structure for
 *					compactness.
 *		Matt Day	:	nonblock connect error handler
 *		Alan Cox	:	Allow large numbers of pending sockets
 *					(eg for big web sites), but only if
 *					specifically application requested.
 *		Alan Cox	:	New buffering throughout IP. Used
 *					dumbly.
 *		Alan Cox	:	New buffering now used smartly.
 *		Alan Cox	:	BSD rather than common sense
 *					interpretation of listen.
 *		Germano Caronni	:	Assorted small races.
 *		Alan Cox	:	sendmsg/recvmsg basic support.
 *		Alan Cox	:	Only sendmsg/recvmsg now supported.
 *		Alan Cox	:	Locked down bind (see security list).
 *		Alan Cox	:	Loosened bind a little.
 *		Mike McLagan	:	ADD/DEL DLCI Ioctls
 *	Willy Konynenberg	:	Transparent proxying support.
 *		David S. Miller	:	New socket lookup architecture.
 *					Some other random speedups.
 *		Cyrus Durgin	:	Cleaned up file for kmod hacks.
 *		Andi Kleen	:	Fix inet_stream_connect TCP race.
 *
 *		This program is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 */

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#include <linux/err.h>
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#include <linux/errno.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/timer.h>
#include <linux/string.h>
#include <linux/sockios.h>
#include <linux/net.h>
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#include <linux/capability.h>
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#include <linux/fcntl.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/stat.h>
#include <linux/init.h>
#include <linux/poll.h>
#include <linux/netfilter_ipv4.h>
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#include <linux/random.h>
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#include <asm/uaccess.h>
#include <asm/system.h>

#include <linux/inet.h>
#include <linux/igmp.h>
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#include <linux/inetdevice.h>
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#include <linux/netdevice.h>
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#include <net/checksum.h>
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#include <net/ip.h>
#include <net/protocol.h>
#include <net/arp.h>
#include <net/route.h>
#include <net/ip_fib.h>
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#include <net/inet_connection_sock.h>
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#include <net/tcp.h>
#include <net/udp.h>
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#include <net/udplite.h>
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#include <linux/skbuff.h>
#include <net/sock.h>
#include <net/raw.h>
#include <net/icmp.h>
#include <net/ipip.h>
#include <net/inet_common.h>
#include <net/xfrm.h>
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#include <net/net_namespace.h>
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#ifdef CONFIG_IP_MROUTE
#include <linux/mroute.h>
#endif


/* The inetsw table contains everything that inet_create needs to
 * build a new socket.
 */
static struct list_head inetsw[SOCK_MAX];
static DEFINE_SPINLOCK(inetsw_lock);

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struct ipv4_config ipv4_config;
EXPORT_SYMBOL(ipv4_config);

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/* New destruction routine */

void inet_sock_destruct(struct sock *sk)
{
	struct inet_sock *inet = inet_sk(sk);

	__skb_queue_purge(&sk->sk_receive_queue);
	__skb_queue_purge(&sk->sk_error_queue);

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	sk_mem_reclaim(sk);

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	if (sk->sk_type == SOCK_STREAM && sk->sk_state != TCP_CLOSE) {
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		pr_err("Attempt to release TCP socket in state %d %p\n",
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		       sk->sk_state, sk);
		return;
	}
	if (!sock_flag(sk, SOCK_DEAD)) {
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		pr_err("Attempt to release alive inet socket %p\n", sk);
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		return;
	}

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	WARN_ON(atomic_read(&sk->sk_rmem_alloc));
	WARN_ON(atomic_read(&sk->sk_wmem_alloc));
	WARN_ON(sk->sk_wmem_queued);
	WARN_ON(sk->sk_forward_alloc);
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	kfree(inet->opt);
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	dst_release(sk->sk_dst_cache);
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	sk_refcnt_debug_dec(sk);
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}
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EXPORT_SYMBOL(inet_sock_destruct);
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/*
 *	The routines beyond this point handle the behaviour of an AF_INET
 *	socket object. Mostly it punts to the subprotocols of IP to do
 *	the work.
 */

/*
 *	Automatically bind an unbound socket.
 */

static int inet_autobind(struct sock *sk)
{
	struct inet_sock *inet;
	/* We may need to bind the socket. */
	lock_sock(sk);
	inet = inet_sk(sk);
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	if (!inet->inet_num) {
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		if (sk->sk_prot->get_port(sk, 0)) {
			release_sock(sk);
			return -EAGAIN;
		}
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		inet->inet_sport = htons(inet->inet_num);
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	}
	release_sock(sk);
	return 0;
}

/*
 *	Move a socket into listening state.
 */
int inet_listen(struct socket *sock, int backlog)
{
	struct sock *sk = sock->sk;
	unsigned char old_state;
	int err;

	lock_sock(sk);

	err = -EINVAL;
	if (sock->state != SS_UNCONNECTED || sock->type != SOCK_STREAM)
		goto out;

	old_state = sk->sk_state;
	if (!((1 << old_state) & (TCPF_CLOSE | TCPF_LISTEN)))
		goto out;

	/* Really, if the socket is already in listen state
	 * we can only allow the backlog to be adjusted.
	 */
	if (old_state != TCP_LISTEN) {
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		err = inet_csk_listen_start(sk, backlog);
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		if (err)
			goto out;
	}
	sk->sk_max_ack_backlog = backlog;
	err = 0;

out:
	release_sock(sk);
	return err;
}
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EXPORT_SYMBOL(inet_listen);
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u32 inet_ehash_secret __read_mostly;
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EXPORT_SYMBOL(inet_ehash_secret);

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/*
 * inet_ehash_secret must be set exactly once
 * Instead of using a dedicated spinlock, we (ab)use inetsw_lock
 */
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void build_ehash_secret(void)
{
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	u32 rnd;
	do {
		get_random_bytes(&rnd, sizeof(rnd));
	} while (rnd == 0);
	spin_lock_bh(&inetsw_lock);
	if (!inet_ehash_secret)
		inet_ehash_secret = rnd;
	spin_unlock_bh(&inetsw_lock);
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}
EXPORT_SYMBOL(build_ehash_secret);

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static inline int inet_netns_ok(struct net *net, int protocol)
{
	int hash;
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	const struct net_protocol *ipprot;
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	if (net_eq(net, &init_net))
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		return 1;

	hash = protocol & (MAX_INET_PROTOS - 1);
	ipprot = rcu_dereference(inet_protos[hash]);

	if (ipprot == NULL)
		/* raw IP is OK */
		return 1;
	return ipprot->netns_ok;
}

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/*
 *	Create an inet socket.
 */

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static int inet_create(struct net *net, struct socket *sock, int protocol,
		       int kern)
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{
	struct sock *sk;
	struct inet_protosw *answer;
	struct inet_sock *inet;
	struct proto *answer_prot;
	unsigned char answer_flags;
	char answer_no_check;
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	int try_loading_module = 0;
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	int err;
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	if (unlikely(!inet_ehash_secret))
		if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM)
			build_ehash_secret();
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	sock->state = SS_UNCONNECTED;

	/* Look for the requested type/protocol pair. */
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lookup_protocol:
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	err = -ESOCKTNOSUPPORT;
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	rcu_read_lock();
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	list_for_each_entry_rcu(answer, &inetsw[sock->type], list) {
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		err = 0;
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		/* Check the non-wild match. */
		if (protocol == answer->protocol) {
			if (protocol != IPPROTO_IP)
				break;
		} else {
			/* Check for the two wild cases. */
			if (IPPROTO_IP == protocol) {
				protocol = answer->protocol;
				break;
			}
			if (IPPROTO_IP == answer->protocol)
				break;
		}
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		err = -EPROTONOSUPPORT;
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	}

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	if (unlikely(err)) {
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		if (try_loading_module < 2) {
			rcu_read_unlock();
			/*
			 * Be more specific, e.g. net-pf-2-proto-132-type-1
			 * (net-pf-PF_INET-proto-IPPROTO_SCTP-type-SOCK_STREAM)
			 */
			if (++try_loading_module == 1)
				request_module("net-pf-%d-proto-%d-type-%d",
					       PF_INET, protocol, sock->type);
			/*
			 * Fall back to generic, e.g. net-pf-2-proto-132
			 * (net-pf-PF_INET-proto-IPPROTO_SCTP)
			 */
			else
				request_module("net-pf-%d-proto-%d",
					       PF_INET, protocol);
			goto lookup_protocol;
		} else
			goto out_rcu_unlock;
	}

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	err = -EPERM;
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	if (sock->type == SOCK_RAW && !kern && !capable(CAP_NET_RAW))
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		goto out_rcu_unlock;

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	err = -EAFNOSUPPORT;
	if (!inet_netns_ok(net, protocol))
		goto out_rcu_unlock;

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	sock->ops = answer->ops;
	answer_prot = answer->prot;
	answer_no_check = answer->no_check;
	answer_flags = answer->flags;
	rcu_read_unlock();

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	WARN_ON(answer_prot->slab == NULL);
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	err = -ENOBUFS;
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	sk = sk_alloc(net, PF_INET, GFP_KERNEL, answer_prot);
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	if (sk == NULL)
		goto out;

	err = 0;
	sk->sk_no_check = answer_no_check;
	if (INET_PROTOSW_REUSE & answer_flags)
		sk->sk_reuse = 1;

	inet = inet_sk(sk);
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	inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
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	if (SOCK_RAW == sock->type) {
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		inet->inet_num = protocol;
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		if (IPPROTO_RAW == protocol)
			inet->hdrincl = 1;
	}

	if (ipv4_config.no_pmtu_disc)
		inet->pmtudisc = IP_PMTUDISC_DONT;
	else
		inet->pmtudisc = IP_PMTUDISC_WANT;

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	inet->inet_id = 0;
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	sock_init_data(sock, sk);

	sk->sk_destruct	   = inet_sock_destruct;
	sk->sk_protocol	   = protocol;
	sk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;

	inet->uc_ttl	= -1;
	inet->mc_loop	= 1;
	inet->mc_ttl	= 1;
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	inet->mc_all	= 1;
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	inet->mc_index	= 0;
	inet->mc_list	= NULL;

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	sk_refcnt_debug_inc(sk);
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	if (inet->inet_num) {
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		/* It assumes that any protocol which allows
		 * the user to assign a number at socket
		 * creation time automatically
		 * shares.
		 */
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		inet->inet_sport = htons(inet->inet_num);
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		/* Add to protocol hash chains. */
		sk->sk_prot->hash(sk);
	}

	if (sk->sk_prot->init) {
		err = sk->sk_prot->init(sk);
		if (err)
			sk_common_release(sk);
	}
out:
	return err;
out_rcu_unlock:
	rcu_read_unlock();
	goto out;
}


/*
 *	The peer socket should always be NULL (or else). When we call this
 *	function we are destroying the object and from then on nobody
 *	should refer to it.
 */
int inet_release(struct socket *sock)
{
	struct sock *sk = sock->sk;

	if (sk) {
		long timeout;

		/* Applications forget to leave groups before exiting */
		ip_mc_drop_socket(sk);

		/* If linger is set, we don't return until the close
		 * is complete.  Otherwise we return immediately. The
		 * actually closing is done the same either way.
		 *
		 * If the close is due to the process exiting, we never
		 * linger..
		 */
		timeout = 0;
		if (sock_flag(sk, SOCK_LINGER) &&
		    !(current->flags & PF_EXITING))
			timeout = sk->sk_lingertime;
		sock->sk = NULL;
		sk->sk_prot->close(sk, timeout);
	}
	return 0;
}
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EXPORT_SYMBOL(inet_release);
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/* It is off by default, see below. */
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int sysctl_ip_nonlocal_bind __read_mostly;
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EXPORT_SYMBOL(sysctl_ip_nonlocal_bind);
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int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
{
	struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
	struct sock *sk = sock->sk;
	struct inet_sock *inet = inet_sk(sk);
	unsigned short snum;
	int chk_addr_ret;
	int err;

	/* If the socket has its own bind function then use it. (RAW) */
	if (sk->sk_prot->bind) {
		err = sk->sk_prot->bind(sk, uaddr, addr_len);
		goto out;
	}
	err = -EINVAL;
	if (addr_len < sizeof(struct sockaddr_in))
		goto out;

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	chk_addr_ret = inet_addr_type(sock_net(sk), addr->sin_addr.s_addr);
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	/* Not specified by any standard per-se, however it breaks too
	 * many applications when removed.  It is unfortunate since
	 * allowing applications to make a non-local bind solves
	 * several problems with systems using dynamic addressing.
	 * (ie. your servers still start up even if your ISDN link
	 *  is temporarily down)
	 */
	err = -EADDRNOTAVAIL;
	if (!sysctl_ip_nonlocal_bind &&
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	    !(inet->freebind || inet->transparent) &&
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	    addr->sin_addr.s_addr != htonl(INADDR_ANY) &&
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	    chk_addr_ret != RTN_LOCAL &&
	    chk_addr_ret != RTN_MULTICAST &&
	    chk_addr_ret != RTN_BROADCAST)
		goto out;

	snum = ntohs(addr->sin_port);
	err = -EACCES;
	if (snum && snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
		goto out;

	/*      We keep a pair of addresses. rcv_saddr is the one
	 *      used by hash lookups, and saddr is used for transmit.
	 *
	 *      In the BSD API these are the same except where it
	 *      would be illegal to use them (multicast/broadcast) in
	 *      which case the sending device address is used.
	 */
	lock_sock(sk);

	/* Check these errors (active socket, double bind). */
	err = -EINVAL;
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	if (sk->sk_state != TCP_CLOSE || inet->inet_num)
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		goto out_release_sock;

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	inet->inet_rcv_saddr = inet->inet_saddr = addr->sin_addr.s_addr;
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	if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST)
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		inet->inet_saddr = 0;  /* Use device */
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	/* Make sure we are allowed to bind here. */
	if (sk->sk_prot->get_port(sk, snum)) {
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		inet->inet_saddr = inet->inet_rcv_saddr = 0;
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		err = -EADDRINUSE;
		goto out_release_sock;
	}

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	if (inet->inet_rcv_saddr)
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		sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
	if (snum)
		sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
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	inet->inet_sport = htons(inet->inet_num);
	inet->inet_daddr = 0;
	inet->inet_dport = 0;
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	sk_dst_reset(sk);
	err = 0;
out_release_sock:
	release_sock(sk);
out:
	return err;
}
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EXPORT_SYMBOL(inet_bind);
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int inet_dgram_connect(struct socket *sock, struct sockaddr * uaddr,
		       int addr_len, int flags)
{
	struct sock *sk = sock->sk;

	if (uaddr->sa_family == AF_UNSPEC)
		return sk->sk_prot->disconnect(sk, flags);

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	if (!inet_sk(sk)->inet_num && inet_autobind(sk))
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		return -EAGAIN;
	return sk->sk_prot->connect(sk, (struct sockaddr *)uaddr, addr_len);
}
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EXPORT_SYMBOL(inet_dgram_connect);
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static long inet_wait_for_connect(struct sock *sk, long timeo)
{
	DEFINE_WAIT(wait);

	prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);

	/* Basic assumption: if someone sets sk->sk_err, he _must_
	 * change state of the socket from TCP_SYN_*.
	 * Connect() does not allow to get error notifications
	 * without closing the socket.
	 */
	while ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
		release_sock(sk);
		timeo = schedule_timeout(timeo);
		lock_sock(sk);
		if (signal_pending(current) || !timeo)
			break;
		prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
	}
	finish_wait(sk->sk_sleep, &wait);
	return timeo;
}

/*
 *	Connect to a remote host. There is regrettably still a little
 *	TCP 'magic' in here.
 */
int inet_stream_connect(struct socket *sock, struct sockaddr *uaddr,
			int addr_len, int flags)
{
	struct sock *sk = sock->sk;
	int err;
	long timeo;

	lock_sock(sk);

	if (uaddr->sa_family == AF_UNSPEC) {
		err = sk->sk_prot->disconnect(sk, flags);
		sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
		goto out;
	}

	switch (sock->state) {
	default:
		err = -EINVAL;
		goto out;
	case SS_CONNECTED:
		err = -EISCONN;
		goto out;
	case SS_CONNECTING:
		err = -EALREADY;
		/* Fall out of switch with err, set for this state */
		break;
	case SS_UNCONNECTED:
		err = -EISCONN;
		if (sk->sk_state != TCP_CLOSE)
			goto out;

		err = sk->sk_prot->connect(sk, uaddr, addr_len);
		if (err < 0)
			goto out;

604
		sock->state = SS_CONNECTING;
L
Linus Torvalds 已提交
605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649

		/* Just entered SS_CONNECTING state; the only
		 * difference is that return value in non-blocking
		 * case is EINPROGRESS, rather than EALREADY.
		 */
		err = -EINPROGRESS;
		break;
	}

	timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);

	if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
		/* Error code is set above */
		if (!timeo || !inet_wait_for_connect(sk, timeo))
			goto out;

		err = sock_intr_errno(timeo);
		if (signal_pending(current))
			goto out;
	}

	/* Connection was closed by RST, timeout, ICMP error
	 * or another process disconnected us.
	 */
	if (sk->sk_state == TCP_CLOSE)
		goto sock_error;

	/* sk->sk_err may be not zero now, if RECVERR was ordered by user
	 * and error was received after socket entered established state.
	 * Hence, it is handled normally after connect() return successfully.
	 */

	sock->state = SS_CONNECTED;
	err = 0;
out:
	release_sock(sk);
	return err;

sock_error:
	err = sock_error(sk) ? : -ECONNABORTED;
	sock->state = SS_UNCONNECTED;
	if (sk->sk_prot->disconnect(sk, flags))
		sock->state = SS_DISCONNECTING;
	goto out;
}
E
Eric Dumazet 已提交
650
EXPORT_SYMBOL(inet_stream_connect);
L
Linus Torvalds 已提交
651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666

/*
 *	Accept a pending connection. The TCP layer now gives BSD semantics.
 */

int inet_accept(struct socket *sock, struct socket *newsock, int flags)
{
	struct sock *sk1 = sock->sk;
	int err = -EINVAL;
	struct sock *sk2 = sk1->sk_prot->accept(sk1, flags, &err);

	if (!sk2)
		goto do_err;

	lock_sock(sk2);

667 668
	WARN_ON(!((1 << sk2->sk_state) &
		  (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT | TCPF_CLOSE)));
L
Linus Torvalds 已提交
669 670 671 672 673 674 675 676 677

	sock_graft(sk2, newsock);

	newsock->state = SS_CONNECTED;
	err = 0;
	release_sock(sk2);
do_err:
	return err;
}
E
Eric Dumazet 已提交
678
EXPORT_SYMBOL(inet_accept);
L
Linus Torvalds 已提交
679 680 681 682 683 684 685 686 687 688


/*
 *	This does both peername and sockname.
 */
int inet_getname(struct socket *sock, struct sockaddr *uaddr,
			int *uaddr_len, int peer)
{
	struct sock *sk		= sock->sk;
	struct inet_sock *inet	= inet_sk(sk);
689
	DECLARE_SOCKADDR(struct sockaddr_in *, sin, uaddr);
L
Linus Torvalds 已提交
690 691 692

	sin->sin_family = AF_INET;
	if (peer) {
E
Eric Dumazet 已提交
693
		if (!inet->inet_dport ||
L
Linus Torvalds 已提交
694 695 696
		    (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
		     peer == 1))
			return -ENOTCONN;
E
Eric Dumazet 已提交
697 698
		sin->sin_port = inet->inet_dport;
		sin->sin_addr.s_addr = inet->inet_daddr;
L
Linus Torvalds 已提交
699
	} else {
E
Eric Dumazet 已提交
700
		__be32 addr = inet->inet_rcv_saddr;
L
Linus Torvalds 已提交
701
		if (!addr)
E
Eric Dumazet 已提交
702 703
			addr = inet->inet_saddr;
		sin->sin_port = inet->inet_sport;
L
Linus Torvalds 已提交
704 705 706 707 708 709
		sin->sin_addr.s_addr = addr;
	}
	memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
	*uaddr_len = sizeof(*sin);
	return 0;
}
E
Eric Dumazet 已提交
710
EXPORT_SYMBOL(inet_getname);
L
Linus Torvalds 已提交
711 712 713 714 715 716 717

int inet_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
		 size_t size)
{
	struct sock *sk = sock->sk;

	/* We may need to bind the socket. */
E
Eric Dumazet 已提交
718
	if (!inet_sk(sk)->inet_num && inet_autobind(sk))
L
Linus Torvalds 已提交
719 720 721 722
		return -EAGAIN;

	return sk->sk_prot->sendmsg(iocb, sk, msg, size);
}
E
Eric Dumazet 已提交
723
EXPORT_SYMBOL(inet_sendmsg);
L
Linus Torvalds 已提交
724 725


E
Eric Dumazet 已提交
726 727
static ssize_t inet_sendpage(struct socket *sock, struct page *page, int offset,
			     size_t size, int flags)
L
Linus Torvalds 已提交
728 729 730 731
{
	struct sock *sk = sock->sk;

	/* We may need to bind the socket. */
E
Eric Dumazet 已提交
732
	if (!inet_sk(sk)->inet_num && inet_autobind(sk))
L
Linus Torvalds 已提交
733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793
		return -EAGAIN;

	if (sk->sk_prot->sendpage)
		return sk->sk_prot->sendpage(sk, page, offset, size, flags);
	return sock_no_sendpage(sock, page, offset, size, flags);
}


int inet_shutdown(struct socket *sock, int how)
{
	struct sock *sk = sock->sk;
	int err = 0;

	/* This should really check to make sure
	 * the socket is a TCP socket. (WHY AC...)
	 */
	how++; /* maps 0->1 has the advantage of making bit 1 rcvs and
		       1->2 bit 2 snds.
		       2->3 */
	if ((how & ~SHUTDOWN_MASK) || !how)	/* MAXINT->0 */
		return -EINVAL;

	lock_sock(sk);
	if (sock->state == SS_CONNECTING) {
		if ((1 << sk->sk_state) &
		    (TCPF_SYN_SENT | TCPF_SYN_RECV | TCPF_CLOSE))
			sock->state = SS_DISCONNECTING;
		else
			sock->state = SS_CONNECTED;
	}

	switch (sk->sk_state) {
	case TCP_CLOSE:
		err = -ENOTCONN;
		/* Hack to wake up other listeners, who can poll for
		   POLLHUP, even on eg. unconnected UDP sockets -- RR */
	default:
		sk->sk_shutdown |= how;
		if (sk->sk_prot->shutdown)
			sk->sk_prot->shutdown(sk, how);
		break;

	/* Remaining two branches are temporary solution for missing
	 * close() in multithreaded environment. It is _not_ a good idea,
	 * but we have no choice until close() is repaired at VFS level.
	 */
	case TCP_LISTEN:
		if (!(how & RCV_SHUTDOWN))
			break;
		/* Fall through */
	case TCP_SYN_SENT:
		err = sk->sk_prot->disconnect(sk, O_NONBLOCK);
		sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
		break;
	}

	/* Wake up anyone sleeping in poll. */
	sk->sk_state_change(sk);
	release_sock(sk);
	return err;
}
E
Eric Dumazet 已提交
794
EXPORT_SYMBOL(inet_shutdown);
L
Linus Torvalds 已提交
795 796 797 798 799 800 801 802 803 804 805 806 807 808 809

/*
 *	ioctl() calls you can issue on an INET socket. Most of these are
 *	device configuration and stuff and very rarely used. Some ioctls
 *	pass on to the socket itself.
 *
 *	NOTE: I like the idea of a module for the config stuff. ie ifconfig
 *	loads the devconfigure module does its configuring and unloads it.
 *	There's a good 20K of config code hanging around the kernel.
 */

int inet_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
{
	struct sock *sk = sock->sk;
	int err = 0;
810
	struct net *net = sock_net(sk);
L
Linus Torvalds 已提交
811 812

	switch (cmd) {
E
Eric Dumazet 已提交
813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847
	case SIOCGSTAMP:
		err = sock_get_timestamp(sk, (struct timeval __user *)arg);
		break;
	case SIOCGSTAMPNS:
		err = sock_get_timestampns(sk, (struct timespec __user *)arg);
		break;
	case SIOCADDRT:
	case SIOCDELRT:
	case SIOCRTMSG:
		err = ip_rt_ioctl(net, cmd, (void __user *)arg);
		break;
	case SIOCDARP:
	case SIOCGARP:
	case SIOCSARP:
		err = arp_ioctl(net, cmd, (void __user *)arg);
		break;
	case SIOCGIFADDR:
	case SIOCSIFADDR:
	case SIOCGIFBRDADDR:
	case SIOCSIFBRDADDR:
	case SIOCGIFNETMASK:
	case SIOCSIFNETMASK:
	case SIOCGIFDSTADDR:
	case SIOCSIFDSTADDR:
	case SIOCSIFPFLAGS:
	case SIOCGIFPFLAGS:
	case SIOCSIFFLAGS:
		err = devinet_ioctl(net, cmd, (void __user *)arg);
		break;
	default:
		if (sk->sk_prot->ioctl)
			err = sk->sk_prot->ioctl(sk, cmd, arg);
		else
			err = -ENOIOCTLCMD;
		break;
L
Linus Torvalds 已提交
848 849 850
	}
	return err;
}
E
Eric Dumazet 已提交
851
EXPORT_SYMBOL(inet_ioctl);
L
Linus Torvalds 已提交
852

853
const struct proto_ops inet_stream_ops = {
854 855 856 857 858 859 860 861 862 863 864 865 866 867
	.family		   = PF_INET,
	.owner		   = THIS_MODULE,
	.release	   = inet_release,
	.bind		   = inet_bind,
	.connect	   = inet_stream_connect,
	.socketpair	   = sock_no_socketpair,
	.accept		   = inet_accept,
	.getname	   = inet_getname,
	.poll		   = tcp_poll,
	.ioctl		   = inet_ioctl,
	.listen		   = inet_listen,
	.shutdown	   = inet_shutdown,
	.setsockopt	   = sock_common_setsockopt,
	.getsockopt	   = sock_common_getsockopt,
868
	.sendmsg	   = tcp_sendmsg,
869 870 871
	.recvmsg	   = sock_common_recvmsg,
	.mmap		   = sock_no_mmap,
	.sendpage	   = tcp_sendpage,
J
Jens Axboe 已提交
872
	.splice_read	   = tcp_splice_read,
873
#ifdef CONFIG_COMPAT
874 875
	.compat_setsockopt = compat_sock_common_setsockopt,
	.compat_getsockopt = compat_sock_common_getsockopt,
876
#endif
L
Linus Torvalds 已提交
877
};
E
Eric Dumazet 已提交
878
EXPORT_SYMBOL(inet_stream_ops);
L
Linus Torvalds 已提交
879

880
const struct proto_ops inet_dgram_ops = {
881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898
	.family		   = PF_INET,
	.owner		   = THIS_MODULE,
	.release	   = inet_release,
	.bind		   = inet_bind,
	.connect	   = inet_dgram_connect,
	.socketpair	   = sock_no_socketpair,
	.accept		   = sock_no_accept,
	.getname	   = inet_getname,
	.poll		   = udp_poll,
	.ioctl		   = inet_ioctl,
	.listen		   = sock_no_listen,
	.shutdown	   = inet_shutdown,
	.setsockopt	   = sock_common_setsockopt,
	.getsockopt	   = sock_common_getsockopt,
	.sendmsg	   = inet_sendmsg,
	.recvmsg	   = sock_common_recvmsg,
	.mmap		   = sock_no_mmap,
	.sendpage	   = inet_sendpage,
899
#ifdef CONFIG_COMPAT
900 901
	.compat_setsockopt = compat_sock_common_setsockopt,
	.compat_getsockopt = compat_sock_common_getsockopt,
902
#endif
L
Linus Torvalds 已提交
903
};
E
Eric Dumazet 已提交
904
EXPORT_SYMBOL(inet_dgram_ops);
L
Linus Torvalds 已提交
905 906 907 908 909

/*
 * For SOCK_RAW sockets; should be the same as inet_dgram_ops but without
 * udp_poll
 */
910
static const struct proto_ops inet_sockraw_ops = {
911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928
	.family		   = PF_INET,
	.owner		   = THIS_MODULE,
	.release	   = inet_release,
	.bind		   = inet_bind,
	.connect	   = inet_dgram_connect,
	.socketpair	   = sock_no_socketpair,
	.accept		   = sock_no_accept,
	.getname	   = inet_getname,
	.poll		   = datagram_poll,
	.ioctl		   = inet_ioctl,
	.listen		   = sock_no_listen,
	.shutdown	   = inet_shutdown,
	.setsockopt	   = sock_common_setsockopt,
	.getsockopt	   = sock_common_getsockopt,
	.sendmsg	   = inet_sendmsg,
	.recvmsg	   = sock_common_recvmsg,
	.mmap		   = sock_no_mmap,
	.sendpage	   = inet_sendpage,
929
#ifdef CONFIG_COMPAT
930 931
	.compat_setsockopt = compat_sock_common_setsockopt,
	.compat_getsockopt = compat_sock_common_getsockopt,
932
#endif
L
Linus Torvalds 已提交
933 934
};

935
static const struct net_proto_family inet_family_ops = {
L
Linus Torvalds 已提交
936 937 938 939 940 941 942 943 944 945
	.family = PF_INET,
	.create = inet_create,
	.owner	= THIS_MODULE,
};

/* Upon startup we insert all the elements in inetsw_array[] into
 * the linked list inetsw.
 */
static struct inet_protosw inetsw_array[] =
{
946 947 948 949 950 951 952
	{
		.type =       SOCK_STREAM,
		.protocol =   IPPROTO_TCP,
		.prot =       &tcp_prot,
		.ops =        &inet_stream_ops,
		.no_check =   0,
		.flags =      INET_PROTOSW_PERMANENT |
953
			      INET_PROTOSW_ICSK,
954 955 956 957 958 959 960 961 962
	},

	{
		.type =       SOCK_DGRAM,
		.protocol =   IPPROTO_UDP,
		.prot =       &udp_prot,
		.ops =        &inet_dgram_ops,
		.no_check =   UDP_CSUM_DEFAULT,
		.flags =      INET_PROTOSW_PERMANENT,
L
Linus Torvalds 已提交
963
       },
964

L
Linus Torvalds 已提交
965 966

       {
967 968 969 970 971 972
	       .type =       SOCK_RAW,
	       .protocol =   IPPROTO_IP,	/* wild card */
	       .prot =       &raw_prot,
	       .ops =        &inet_sockraw_ops,
	       .no_check =   UDP_CSUM_DEFAULT,
	       .flags =      INET_PROTOSW_REUSE,
L
Linus Torvalds 已提交
973 974 975
       }
};

976
#define INETSW_ARRAY_LEN ARRAY_SIZE(inetsw_array)
L
Linus Torvalds 已提交
977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010

void inet_register_protosw(struct inet_protosw *p)
{
	struct list_head *lh;
	struct inet_protosw *answer;
	int protocol = p->protocol;
	struct list_head *last_perm;

	spin_lock_bh(&inetsw_lock);

	if (p->type >= SOCK_MAX)
		goto out_illegal;

	/* If we are trying to override a permanent protocol, bail. */
	answer = NULL;
	last_perm = &inetsw[p->type];
	list_for_each(lh, &inetsw[p->type]) {
		answer = list_entry(lh, struct inet_protosw, list);

		/* Check only the non-wild match. */
		if (INET_PROTOSW_PERMANENT & answer->flags) {
			if (protocol == answer->protocol)
				break;
			last_perm = lh;
		}

		answer = NULL;
	}
	if (answer)
		goto out_permanent;

	/* Add the new entry after the last permanent entry if any, so that
	 * the new entry does not override a permanent entry when matched with
	 * a wild-card protocol. But it is allowed to override any existing
1011
	 * non-permanent entry.  This means that when we remove this entry, the
L
Linus Torvalds 已提交
1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030
	 * system automatically returns to the old behavior.
	 */
	list_add_rcu(&p->list, last_perm);
out:
	spin_unlock_bh(&inetsw_lock);

	return;

out_permanent:
	printk(KERN_ERR "Attempt to override permanent protocol %d.\n",
	       protocol);
	goto out;

out_illegal:
	printk(KERN_ERR
	       "Ignoring attempt to register invalid socket type %d.\n",
	       p->type);
	goto out;
}
E
Eric Dumazet 已提交
1031
EXPORT_SYMBOL(inet_register_protosw);
L
Linus Torvalds 已提交
1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046

void inet_unregister_protosw(struct inet_protosw *p)
{
	if (INET_PROTOSW_PERMANENT & p->flags) {
		printk(KERN_ERR
		       "Attempt to unregister permanent protocol %d.\n",
		       p->protocol);
	} else {
		spin_lock_bh(&inetsw_lock);
		list_del_rcu(&p->list);
		spin_unlock_bh(&inetsw_lock);

		synchronize_net();
	}
}
E
Eric Dumazet 已提交
1047
EXPORT_SYMBOL(inet_unregister_protosw);
L
Linus Torvalds 已提交
1048

1049 1050 1051 1052
/*
 *      Shall we try to damage output packets if routing dev changes?
 */

1053
int sysctl_ip_dynaddr __read_mostly;
1054 1055 1056 1057 1058 1059

static int inet_sk_reselect_saddr(struct sock *sk)
{
	struct inet_sock *inet = inet_sk(sk);
	int err;
	struct rtable *rt;
E
Eric Dumazet 已提交
1060
	__be32 old_saddr = inet->inet_saddr;
1061
	__be32 new_saddr;
E
Eric Dumazet 已提交
1062
	__be32 daddr = inet->inet_daddr;
1063 1064 1065 1066 1067 1068 1069 1070 1071

	if (inet->opt && inet->opt->srr)
		daddr = inet->opt->faddr;

	/* Query new route. */
	err = ip_route_connect(&rt, daddr, 0,
			       RT_CONN_FLAGS(sk),
			       sk->sk_bound_dev_if,
			       sk->sk_protocol,
E
Eric Dumazet 已提交
1072
			       inet->inet_sport, inet->inet_dport, sk, 0);
1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083
	if (err)
		return err;

	sk_setup_caps(sk, &rt->u.dst);

	new_saddr = rt->rt_src;

	if (new_saddr == old_saddr)
		return 0;

	if (sysctl_ip_dynaddr > 1) {
1084 1085
		printk(KERN_INFO "%s(): shifting inet->saddr from %pI4 to %pI4\n",
		       __func__, &old_saddr, &new_saddr);
1086 1087
	}

E
Eric Dumazet 已提交
1088
	inet->inet_saddr = inet->inet_rcv_saddr = new_saddr;
1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105

	/*
	 * XXX The only one ugly spot where we need to
	 * XXX really change the sockets identity after
	 * XXX it has entered the hashes. -DaveM
	 *
	 * Besides that, it does not check for connection
	 * uniqueness. Wait for troubles.
	 */
	__sk_prot_rehash(sk);
	return 0;
}

int inet_sk_rebuild_header(struct sock *sk)
{
	struct inet_sock *inet = inet_sk(sk);
	struct rtable *rt = (struct rtable *)__sk_dst_check(sk, 0);
A
Al Viro 已提交
1106
	__be32 daddr;
1107 1108 1109 1110 1111 1112 1113
	int err;

	/* Route is OK, nothing to do. */
	if (rt)
		return 0;

	/* Reroute. */
E
Eric Dumazet 已提交
1114
	daddr = inet->inet_daddr;
1115 1116 1117 1118 1119
	if (inet->opt && inet->opt->srr)
		daddr = inet->opt->faddr;
{
	struct flowi fl = {
		.oif = sk->sk_bound_dev_if,
1120
		.mark = sk->sk_mark,
1121 1122 1123
		.nl_u = {
			.ip4_u = {
				.daddr	= daddr,
E
Eric Dumazet 已提交
1124
				.saddr	= inet->inet_saddr,
1125 1126 1127 1128
				.tos	= RT_CONN_FLAGS(sk),
			},
		},
		.proto = sk->sk_protocol,
1129
		.flags = inet_sk_flowi_flags(sk),
1130 1131
		.uli_u = {
			.ports = {
E
Eric Dumazet 已提交
1132 1133
				.sport = inet->inet_sport,
				.dport = inet->inet_dport,
1134 1135 1136
			},
		},
	};
1137

V
Venkat Yekkirala 已提交
1138
	security_sk_classify_flow(sk, &fl);
1139
	err = ip_route_output_flow(sock_net(sk), &rt, &fl, sk, 0);
1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160
}
	if (!err)
		sk_setup_caps(sk, &rt->u.dst);
	else {
		/* Routing failed... */
		sk->sk_route_caps = 0;
		/*
		 * Other protocols have to map its equivalent state to TCP_SYN_SENT.
		 * DCCP maps its DCCP_REQUESTING state to TCP_SYN_SENT. -acme
		 */
		if (!sysctl_ip_dynaddr ||
		    sk->sk_state != TCP_SYN_SENT ||
		    (sk->sk_userlocks & SOCK_BINDADDR_LOCK) ||
		    (err = inet_sk_reselect_saddr(sk)) != 0)
			sk->sk_err_soft = -err;
	}

	return err;
}
EXPORT_SYMBOL(inet_sk_rebuild_header);

1161 1162 1163
static int inet_gso_send_check(struct sk_buff *skb)
{
	struct iphdr *iph;
1164
	const struct net_protocol *ops;
1165 1166 1167 1168 1169 1170 1171
	int proto;
	int ihl;
	int err = -EINVAL;

	if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
		goto out;

1172
	iph = ip_hdr(skb);
1173 1174 1175 1176 1177 1178 1179
	ihl = iph->ihl * 4;
	if (ihl < sizeof(*iph))
		goto out;

	if (unlikely(!pskb_may_pull(skb, ihl)))
		goto out;

1180 1181
	__skb_pull(skb, ihl);
	skb_reset_transport_header(skb);
1182
	iph = ip_hdr(skb);
1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195
	proto = iph->protocol & (MAX_INET_PROTOS - 1);
	err = -EPROTONOSUPPORT;

	rcu_read_lock();
	ops = rcu_dereference(inet_protos[proto]);
	if (likely(ops && ops->gso_send_check))
		err = ops->gso_send_check(skb);
	rcu_read_unlock();

out:
	return err;
}

1196
static struct sk_buff *inet_gso_segment(struct sk_buff *skb, int features)
H
Herbert Xu 已提交
1197 1198 1199
{
	struct sk_buff *segs = ERR_PTR(-EINVAL);
	struct iphdr *iph;
1200
	const struct net_protocol *ops;
H
Herbert Xu 已提交
1201 1202 1203
	int proto;
	int ihl;
	int id;
1204
	unsigned int offset = 0;
H
Herbert Xu 已提交
1205

1206 1207 1208
	if (!(features & NETIF_F_V4_CSUM))
		features &= ~NETIF_F_SG;

1209 1210 1211 1212 1213 1214 1215 1216 1217
	if (unlikely(skb_shinfo(skb)->gso_type &
		     ~(SKB_GSO_TCPV4 |
		       SKB_GSO_UDP |
		       SKB_GSO_DODGY |
		       SKB_GSO_TCP_ECN |
		       0)))
		goto out;

	if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
H
Herbert Xu 已提交
1218 1219
		goto out;

1220
	iph = ip_hdr(skb);
H
Herbert Xu 已提交
1221 1222 1223 1224
	ihl = iph->ihl * 4;
	if (ihl < sizeof(*iph))
		goto out;

1225
	if (unlikely(!pskb_may_pull(skb, ihl)))
H
Herbert Xu 已提交
1226 1227
		goto out;

1228 1229
	__skb_pull(skb, ihl);
	skb_reset_transport_header(skb);
1230
	iph = ip_hdr(skb);
H
Herbert Xu 已提交
1231 1232 1233 1234 1235 1236
	id = ntohs(iph->id);
	proto = iph->protocol & (MAX_INET_PROTOS - 1);
	segs = ERR_PTR(-EPROTONOSUPPORT);

	rcu_read_lock();
	ops = rcu_dereference(inet_protos[proto]);
1237
	if (likely(ops && ops->gso_segment))
1238
		segs = ops->gso_segment(skb, features);
H
Herbert Xu 已提交
1239 1240
	rcu_read_unlock();

1241
	if (!segs || IS_ERR(segs))
H
Herbert Xu 已提交
1242 1243 1244 1245
		goto out;

	skb = segs;
	do {
1246
		iph = ip_hdr(skb);
1247 1248 1249 1250 1251 1252 1253 1254
		if (proto == IPPROTO_UDP) {
			iph->id = htons(id);
			iph->frag_off = htons(offset >> 3);
			if (skb->next != NULL)
				iph->frag_off |= htons(IP_MF);
			offset += (skb->len - skb->mac_len - iph->ihl * 4);
		} else
			iph->id = htons(id++);
H
Herbert Xu 已提交
1255 1256
		iph->tot_len = htons(skb->len - skb->mac_len);
		iph->check = 0;
1257
		iph->check = ip_fast_csum(skb_network_header(skb), iph->ihl);
H
Herbert Xu 已提交
1258 1259 1260 1261 1262 1263
	} while ((skb = skb->next));

out:
	return segs;
}

H
Herbert Xu 已提交
1264 1265 1266
static struct sk_buff **inet_gro_receive(struct sk_buff **head,
					 struct sk_buff *skb)
{
1267
	const struct net_protocol *ops;
H
Herbert Xu 已提交
1268 1269 1270
	struct sk_buff **pp = NULL;
	struct sk_buff *p;
	struct iphdr *iph;
1271 1272
	unsigned int hlen;
	unsigned int off;
1273
	unsigned int id;
H
Herbert Xu 已提交
1274 1275 1276
	int flush = 1;
	int proto;

1277 1278 1279 1280 1281 1282 1283 1284
	off = skb_gro_offset(skb);
	hlen = off + sizeof(*iph);
	iph = skb_gro_header_fast(skb, off);
	if (skb_gro_header_hard(skb, hlen)) {
		iph = skb_gro_header_slow(skb, hlen, off);
		if (unlikely(!iph))
			goto out;
	}
H
Herbert Xu 已提交
1285 1286 1287 1288 1289 1290 1291 1292

	proto = iph->protocol & (MAX_INET_PROTOS - 1);

	rcu_read_lock();
	ops = rcu_dereference(inet_protos[proto]);
	if (!ops || !ops->gro_receive)
		goto out_unlock;

H
Herbert Xu 已提交
1293
	if (*(u8 *)iph != 0x45)
H
Herbert Xu 已提交
1294 1295 1296 1297 1298
		goto out_unlock;

	if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
		goto out_unlock;

1299 1300 1301
	id = ntohl(*(u32 *)&iph->id);
	flush = (u16)((ntohl(*(u32 *)iph) ^ skb_gro_len(skb)) | (id ^ IP_DF));
	id >>= 16;
H
Herbert Xu 已提交
1302 1303 1304 1305 1306 1307 1308 1309 1310

	for (p = *head; p; p = p->next) {
		struct iphdr *iph2;

		if (!NAPI_GRO_CB(p)->same_flow)
			continue;

		iph2 = ip_hdr(p);

H
Herbert Xu 已提交
1311 1312 1313 1314
		if ((iph->protocol ^ iph2->protocol) |
		    (iph->tos ^ iph2->tos) |
		    (iph->saddr ^ iph2->saddr) |
		    (iph->daddr ^ iph2->daddr)) {
H
Herbert Xu 已提交
1315 1316 1317 1318 1319 1320
			NAPI_GRO_CB(p)->same_flow = 0;
			continue;
		}

		/* All fields must match except length and checksum. */
		NAPI_GRO_CB(p)->flush |=
H
Herbert Xu 已提交
1321 1322
			(iph->ttl ^ iph2->ttl) |
			((u16)(ntohs(iph2->id) + NAPI_GRO_CB(p)->count) ^ id);
H
Herbert Xu 已提交
1323 1324 1325 1326 1327

		NAPI_GRO_CB(p)->flush |= flush;
	}

	NAPI_GRO_CB(skb)->flush |= flush;
1328 1329
	skb_gro_pull(skb, sizeof(*iph));
	skb_set_transport_header(skb, skb_gro_offset(skb));
H
Herbert Xu 已提交
1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343

	pp = ops->gro_receive(head, skb);

out_unlock:
	rcu_read_unlock();

out:
	NAPI_GRO_CB(skb)->flush |= flush;

	return pp;
}

static int inet_gro_complete(struct sk_buff *skb)
{
1344
	const struct net_protocol *ops;
H
Herbert Xu 已提交
1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365
	struct iphdr *iph = ip_hdr(skb);
	int proto = iph->protocol & (MAX_INET_PROTOS - 1);
	int err = -ENOSYS;
	__be16 newlen = htons(skb->len - skb_network_offset(skb));

	csum_replace2(&iph->check, iph->tot_len, newlen);
	iph->tot_len = newlen;

	rcu_read_lock();
	ops = rcu_dereference(inet_protos[proto]);
	if (WARN_ON(!ops || !ops->gro_complete))
		goto out_unlock;

	err = ops->gro_complete(skb);

out_unlock:
	rcu_read_unlock();

	return err;
}

1366
int inet_ctl_sock_create(struct sock **sk, unsigned short family,
1367 1368
			 unsigned short type, unsigned char protocol,
			 struct net *net)
1369
{
1370 1371
	struct socket *sock;
	int rc = sock_create_kern(family, type, protocol, &sock);
1372 1373

	if (rc == 0) {
1374 1375
		*sk = sock->sk;
		(*sk)->sk_allocation = GFP_ATOMIC;
1376 1377 1378 1379
		/*
		 * Unhash it so that IP input processing does not even see it,
		 * we do not wish this socket to see incoming packets.
		 */
1380
		(*sk)->sk_prot->unhash(*sk);
1381 1382

		sk_change_net(*sk, net);
1383 1384 1385 1386 1387
	}
	return rc;
}
EXPORT_SYMBOL_GPL(inet_ctl_sock_create);

1388
unsigned long snmp_fold_field(void __percpu *mib[], int offt)
1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400
{
	unsigned long res = 0;
	int i;

	for_each_possible_cpu(i) {
		res += *(((unsigned long *) per_cpu_ptr(mib[0], i)) + offt);
		res += *(((unsigned long *) per_cpu_ptr(mib[1], i)) + offt);
	}
	return res;
}
EXPORT_SYMBOL_GPL(snmp_fold_field);

1401
int snmp_mib_init(void __percpu *ptr[2], size_t mibsize)
1402 1403
{
	BUG_ON(ptr == NULL);
1404
	ptr[0] = __alloc_percpu(mibsize, __alignof__(unsigned long long));
1405 1406
	if (!ptr[0])
		goto err0;
1407
	ptr[1] = __alloc_percpu(mibsize, __alignof__(unsigned long long));
1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418
	if (!ptr[1])
		goto err1;
	return 0;
err1:
	free_percpu(ptr[0]);
	ptr[0] = NULL;
err0:
	return -ENOMEM;
}
EXPORT_SYMBOL_GPL(snmp_mib_init);

1419
void snmp_mib_free(void __percpu *ptr[2])
1420 1421 1422 1423 1424 1425 1426 1427
{
	BUG_ON(ptr == NULL);
	free_percpu(ptr[0]);
	free_percpu(ptr[1]);
	ptr[0] = ptr[1] = NULL;
}
EXPORT_SYMBOL_GPL(snmp_mib_free);

L
Linus Torvalds 已提交
1428
#ifdef CONFIG_IP_MULTICAST
1429
static const struct net_protocol igmp_protocol = {
L
Linus Torvalds 已提交
1430
	.handler =	igmp_rcv,
1431
	.netns_ok =	1,
L
Linus Torvalds 已提交
1432 1433 1434
};
#endif

1435
static const struct net_protocol tcp_protocol = {
L
Linus Torvalds 已提交
1436 1437
	.handler =	tcp_v4_rcv,
	.err_handler =	tcp_v4_err,
1438
	.gso_send_check = tcp_v4_gso_send_check,
H
Herbert Xu 已提交
1439
	.gso_segment =	tcp_tso_segment,
H
Herbert Xu 已提交
1440 1441
	.gro_receive =	tcp4_gro_receive,
	.gro_complete =	tcp4_gro_complete,
L
Linus Torvalds 已提交
1442
	.no_policy =	1,
1443
	.netns_ok =	1,
L
Linus Torvalds 已提交
1444 1445
};

1446
static const struct net_protocol udp_protocol = {
L
Linus Torvalds 已提交
1447 1448
	.handler =	udp_rcv,
	.err_handler =	udp_err,
1449 1450
	.gso_send_check = udp4_ufo_send_check,
	.gso_segment = udp4_ufo_fragment,
L
Linus Torvalds 已提交
1451
	.no_policy =	1,
1452
	.netns_ok =	1,
L
Linus Torvalds 已提交
1453 1454
};

1455
static const struct net_protocol icmp_protocol = {
L
Linus Torvalds 已提交
1456
	.handler =	icmp_rcv,
1457
	.no_policy =	1,
1458
	.netns_ok =	1,
L
Linus Torvalds 已提交
1459 1460
};

1461 1462
static __net_init int ipv4_mib_init_net(struct net *net)
{
1463
	if (snmp_mib_init((void __percpu **)net->mib.tcp_statistics,
1464 1465
			  sizeof(struct tcp_mib)) < 0)
		goto err_tcp_mib;
1466
	if (snmp_mib_init((void __percpu **)net->mib.ip_statistics,
1467 1468
			  sizeof(struct ipstats_mib)) < 0)
		goto err_ip_mib;
1469
	if (snmp_mib_init((void __percpu **)net->mib.net_statistics,
1470 1471
			  sizeof(struct linux_mib)) < 0)
		goto err_net_mib;
1472
	if (snmp_mib_init((void __percpu **)net->mib.udp_statistics,
1473 1474
			  sizeof(struct udp_mib)) < 0)
		goto err_udp_mib;
1475
	if (snmp_mib_init((void __percpu **)net->mib.udplite_statistics,
1476 1477
			  sizeof(struct udp_mib)) < 0)
		goto err_udplite_mib;
1478
	if (snmp_mib_init((void __percpu **)net->mib.icmp_statistics,
1479 1480
			  sizeof(struct icmp_mib)) < 0)
		goto err_icmp_mib;
1481
	if (snmp_mib_init((void __percpu **)net->mib.icmpmsg_statistics,
1482 1483
			  sizeof(struct icmpmsg_mib)) < 0)
		goto err_icmpmsg_mib;
1484 1485

	tcp_mib_init(net);
1486
	return 0;
1487

1488
err_icmpmsg_mib:
1489
	snmp_mib_free((void __percpu **)net->mib.icmp_statistics);
1490
err_icmp_mib:
1491
	snmp_mib_free((void __percpu **)net->mib.udplite_statistics);
1492
err_udplite_mib:
1493
	snmp_mib_free((void __percpu **)net->mib.udp_statistics);
1494
err_udp_mib:
1495
	snmp_mib_free((void __percpu **)net->mib.net_statistics);
1496
err_net_mib:
1497
	snmp_mib_free((void __percpu **)net->mib.ip_statistics);
1498
err_ip_mib:
1499
	snmp_mib_free((void __percpu **)net->mib.tcp_statistics);
1500 1501
err_tcp_mib:
	return -ENOMEM;
1502 1503 1504 1505
}

static __net_exit void ipv4_mib_exit_net(struct net *net)
{
1506 1507 1508 1509 1510 1511 1512
	snmp_mib_free((void __percpu **)net->mib.icmpmsg_statistics);
	snmp_mib_free((void __percpu **)net->mib.icmp_statistics);
	snmp_mib_free((void __percpu **)net->mib.udplite_statistics);
	snmp_mib_free((void __percpu **)net->mib.udp_statistics);
	snmp_mib_free((void __percpu **)net->mib.net_statistics);
	snmp_mib_free((void __percpu **)net->mib.ip_statistics);
	snmp_mib_free((void __percpu **)net->mib.tcp_statistics);
1513 1514 1515 1516 1517 1518 1519
}

static __net_initdata struct pernet_operations ipv4_mib_ops = {
	.init = ipv4_mib_init_net,
	.exit = ipv4_mib_exit_net,
};

L
Linus Torvalds 已提交
1520 1521
static int __init init_ipv4_mibs(void)
{
1522
	return register_pernet_subsys(&ipv4_mib_ops);
L
Linus Torvalds 已提交
1523 1524 1525 1526
}

static int ipv4_proc_init(void);

1527 1528 1529 1530
/*
 *	IP protocol layer initialiser
 */

1531
static struct packet_type ip_packet_type __read_mostly = {
1532
	.type = cpu_to_be16(ETH_P_IP),
1533
	.func = ip_rcv,
1534
	.gso_send_check = inet_gso_send_check,
H
Herbert Xu 已提交
1535
	.gso_segment = inet_gso_segment,
H
Herbert Xu 已提交
1536 1537
	.gro_receive = inet_gro_receive,
	.gro_complete = inet_gro_complete,
1538 1539
};

L
Linus Torvalds 已提交
1540 1541 1542 1543 1544 1545 1546
static int __init inet_init(void)
{
	struct sk_buff *dummy_skb;
	struct inet_protosw *q;
	struct list_head *r;
	int rc = -EINVAL;

1547
	BUILD_BUG_ON(sizeof(struct inet_skb_parm) > sizeof(dummy_skb->cb));
L
Linus Torvalds 已提交
1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561

	rc = proto_register(&tcp_prot, 1);
	if (rc)
		goto out;

	rc = proto_register(&udp_prot, 1);
	if (rc)
		goto out_unregister_tcp_proto;

	rc = proto_register(&raw_prot, 1);
	if (rc)
		goto out_unregister_udp_proto;

	/*
1562
	 *	Tell SOCKET that we are alive...
L
Linus Torvalds 已提交
1563 1564
	 */

1565
	(void)sock_register(&inet_family_ops);
L
Linus Torvalds 已提交
1566

1567 1568 1569 1570
#ifdef CONFIG_SYSCTL
	ip_static_sysctl_init();
#endif

L
Linus Torvalds 已提交
1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598
	/*
	 *	Add all the base protocols.
	 */

	if (inet_add_protocol(&icmp_protocol, IPPROTO_ICMP) < 0)
		printk(KERN_CRIT "inet_init: Cannot add ICMP protocol\n");
	if (inet_add_protocol(&udp_protocol, IPPROTO_UDP) < 0)
		printk(KERN_CRIT "inet_init: Cannot add UDP protocol\n");
	if (inet_add_protocol(&tcp_protocol, IPPROTO_TCP) < 0)
		printk(KERN_CRIT "inet_init: Cannot add TCP protocol\n");
#ifdef CONFIG_IP_MULTICAST
	if (inet_add_protocol(&igmp_protocol, IPPROTO_IGMP) < 0)
		printk(KERN_CRIT "inet_init: Cannot add IGMP protocol\n");
#endif

	/* Register the socket-side information for inet_create. */
	for (r = &inetsw[0]; r < &inetsw[SOCK_MAX]; ++r)
		INIT_LIST_HEAD(r);

	for (q = inetsw_array; q < &inetsw_array[INETSW_ARRAY_LEN]; ++q)
		inet_register_protosw(q);

	/*
	 *	Set the ARP module up
	 */

	arp_init();

1599 1600 1601
	/*
	 *	Set the IP module up
	 */
L
Linus Torvalds 已提交
1602 1603 1604

	ip_init();

1605
	tcp_v4_init();
L
Linus Torvalds 已提交
1606 1607 1608 1609

	/* Setup TCP slab cache for open requests. */
	tcp_init();

H
Hideo Aoki 已提交
1610 1611 1612
	/* Setup UDP memory threshold */
	udp_init();

1613 1614
	/* Add UDP-Lite (RFC 3828) */
	udplite4_register();
L
Linus Torvalds 已提交
1615 1616 1617 1618 1619

	/*
	 *	Set the ICMP layer up
	 */

1620 1621
	if (icmp_init() < 0)
		panic("Failed to create the ICMP control socket.\n");
L
Linus Torvalds 已提交
1622 1623 1624 1625 1626

	/*
	 *	Initialise the multicast router
	 */
#if defined(CONFIG_IP_MROUTE)
W
Wang Chen 已提交
1627 1628
	if (ip_mr_init())
		printk(KERN_CRIT "inet_init: Cannot init ipv4 mroute\n");
L
Linus Torvalds 已提交
1629 1630 1631
#endif
	/*
	 *	Initialise per-cpu ipv4 mibs
1632
	 */
L
Linus Torvalds 已提交
1633

S
Stephen Hemminger 已提交
1634
	if (init_ipv4_mibs())
W
Wang Chen 已提交
1635
		printk(KERN_CRIT "inet_init: Cannot init ipv4 mibs\n");
1636

L
Linus Torvalds 已提交
1637 1638 1639 1640
	ipv4_proc_init();

	ipfrag_init();

1641 1642
	dev_add_pack(&ip_packet_type);

L
Linus Torvalds 已提交
1643 1644 1645 1646 1647
	rc = 0;
out:
	return rc;
out_unregister_udp_proto:
	proto_unregister(&udp_prot);
1648 1649
out_unregister_tcp_proto:
	proto_unregister(&tcp_prot);
L
Linus Torvalds 已提交
1650 1651 1652
	goto out;
}

1653
fs_initcall(inet_init);
L
Linus Torvalds 已提交
1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691

/* ------------------------------------------------------------------------ */

#ifdef CONFIG_PROC_FS
static int __init ipv4_proc_init(void)
{
	int rc = 0;

	if (raw_proc_init())
		goto out_raw;
	if (tcp4_proc_init())
		goto out_tcp;
	if (udp4_proc_init())
		goto out_udp;
	if (ip_misc_proc_init())
		goto out_misc;
out:
	return rc;
out_misc:
	udp4_proc_exit();
out_udp:
	tcp4_proc_exit();
out_tcp:
	raw_proc_exit();
out_raw:
	rc = -ENOMEM;
	goto out;
}

#else /* CONFIG_PROC_FS */
static int __init ipv4_proc_init(void)
{
	return 0;
}
#endif /* CONFIG_PROC_FS */

MODULE_ALIAS_NETPROTO(PF_INET);