[people/ms/linux.git] / net / l2tp / l2tp_ip.c

// SPDX-License-Identifier: GPL-2.0-or-later
/* L2TPv3 IP encapsulation support
 *
 * Copyright (c) 2008,2009,2010 Katalix Systems Ltd
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <asm/ioctls.h>
#include <linux/icmp.h>
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/random.h>
#include <linux/socket.h>
#include <linux/l2tp.h>
#include <linux/in.h>
#include <net/sock.h>
#include <net/ip.h>
#include <net/icmp.h>
#include <net/udp.h>
#include <net/inet_common.h>
#include <net/tcp_states.h>
#include <net/protocol.h>
#include <net/xfrm.h>

#include "l2tp_core.h"

struct l2tp_ip_sock {
	/* inet_sock has to be the first member of l2tp_ip_sock */
	struct inet_sock	inet;

	u32			conn_id;
	u32			peer_conn_id;
};

static DEFINE_RWLOCK(l2tp_ip_lock);
static struct hlist_head l2tp_ip_table;
static struct hlist_head l2tp_ip_bind_table;

static inline struct l2tp_ip_sock *l2tp_ip_sk(const struct sock *sk)
{
	return (struct l2tp_ip_sock *)sk;
}

static struct sock *__l2tp_ip_bind_lookup(const struct net *net, __be32 laddr,
					  __be32 raddr, int dif, u32 tunnel_id)
{
	struct sock *sk;

	sk_for_each_bound(sk, &l2tp_ip_bind_table) {
		const struct l2tp_ip_sock *l2tp = l2tp_ip_sk(sk);
		const struct inet_sock *inet = inet_sk(sk);
		int bound_dev_if;

		if (!net_eq(sock_net(sk), net))
			continue;

		bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
		if (bound_dev_if && dif && bound_dev_if != dif)
			continue;

		if (inet->inet_rcv_saddr && laddr &&
		    inet->inet_rcv_saddr != laddr)
			continue;

		if (inet->inet_daddr && raddr && inet->inet_daddr != raddr)
			continue;

		if (l2tp->conn_id != tunnel_id)
			continue;

		goto found;
	}

	sk = NULL;
found:
	return sk;
}

/* When processing receive frames, there are two cases to
 * consider. Data frames consist of a non-zero session-id and an
 * optional cookie. Control frames consist of a regular L2TP header
 * preceded by 32-bits of zeros.
 *
 * L2TPv3 Session Header Over IP
 *
 *  0                   1                   2                   3
 *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * |                           Session ID                          |
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * |               Cookie (optional, maximum 64 bits)...
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *                                                                 |
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
 * L2TPv3 Control Message Header Over IP
 *
 *  0                   1                   2                   3
 *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * |                      (32 bits of zeros)                       |
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * |T|L|x|x|S|x|x|x|x|x|x|x|  Ver  |             Length            |
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * |                     Control Connection ID                     |
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * |               Ns              |               Nr              |
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
 * All control frames are passed to userspace.
 */
static int l2tp_ip_recv(struct sk_buff *skb)
{
	struct net *net = dev_net(skb->dev);
	struct sock *sk;
	u32 session_id;
	u32 tunnel_id;
	unsigned char *ptr, *optr;
	struct l2tp_session *session;
	struct l2tp_tunnel *tunnel = NULL;
	struct iphdr *iph;

	if (!pskb_may_pull(skb, 4))
		goto discard;

	/* Point to L2TP header */
	optr = skb->data;
	ptr = skb->data;
	session_id = ntohl(*((__be32 *)ptr));
	ptr += 4;

	/* RFC3931: L2TP/IP packets have the first 4 bytes containing
	 * the session_id. If it is 0, the packet is a L2TP control
	 * frame and the session_id value can be discarded.
	 */
	if (session_id == 0) {
		__skb_pull(skb, 4);
		goto pass_up;
	}

	/* Ok, this is a data packet. Lookup the session. */
	session = l2tp_session_get(net, session_id);
	if (!session)
		goto discard;

	tunnel = session->tunnel;
	if (!tunnel)
		goto discard_sess;

	if (l2tp_v3_ensure_opt_in_linear(session, skb, &ptr, &optr))
		goto discard_sess;

	l2tp_recv_common(session, skb, ptr, optr, 0, skb->len);
	l2tp_session_dec_refcount(session);

	return 0;

pass_up:
	/* Get the tunnel_id from the L2TP header */
	if (!pskb_may_pull(skb, 12))
		goto discard;

	if ((skb->data[0] & 0xc0) != 0xc0)
		goto discard;

	tunnel_id = ntohl(*(__be32 *)&skb->data[4]);
	iph = (struct iphdr *)skb_network_header(skb);

	read_lock_bh(&l2tp_ip_lock);
	sk = __l2tp_ip_bind_lookup(net, iph->daddr, iph->saddr, inet_iif(skb),
				   tunnel_id);
	if (!sk) {
		read_unlock_bh(&l2tp_ip_lock);
		goto discard;
	}
	sock_hold(sk);
	read_unlock_bh(&l2tp_ip_lock);

	if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb))
		goto discard_put;

	nf_reset_ct(skb);

	return sk_receive_skb(sk, skb, 1);

discard_sess:
	l2tp_session_dec_refcount(session);
	goto discard;

discard_put:
	sock_put(sk);

discard:
	kfree_skb(skb);
	return 0;
}

static int l2tp_ip_hash(struct sock *sk)
{
	if (sk_unhashed(sk)) {
		write_lock_bh(&l2tp_ip_lock);
		sk_add_node(sk, &l2tp_ip_table);
		write_unlock_bh(&l2tp_ip_lock);
	}
	return 0;
}

static void l2tp_ip_unhash(struct sock *sk)
{
	if (sk_unhashed(sk))
		return;
	write_lock_bh(&l2tp_ip_lock);
	sk_del_node_init(sk);
	write_unlock_bh(&l2tp_ip_lock);
}

static int l2tp_ip_open(struct sock *sk)
{
	/* Prevent autobind. We don't have ports. */
	inet_sk(sk)->inet_num = IPPROTO_L2TP;

	l2tp_ip_hash(sk);
	return 0;
}

static void l2tp_ip_close(struct sock *sk, long timeout)
{
	write_lock_bh(&l2tp_ip_lock);
	hlist_del_init(&sk->sk_bind_node);
	sk_del_node_init(sk);
	write_unlock_bh(&l2tp_ip_lock);
	sk_common_release(sk);
}

static void l2tp_ip_destroy_sock(struct sock *sk)
{
	struct l2tp_tunnel *tunnel = l2tp_sk_to_tunnel(sk);
	struct sk_buff *skb;

	while ((skb = __skb_dequeue_tail(&sk->sk_write_queue)) != NULL)
		kfree_skb(skb);

	if (tunnel)
		l2tp_tunnel_delete(tunnel);
}

static int l2tp_ip_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
{
	struct inet_sock *inet = inet_sk(sk);
	struct sockaddr_l2tpip *addr = (struct sockaddr_l2tpip *)uaddr;
	struct net *net = sock_net(sk);
	int ret;
	int chk_addr_ret;

	if (addr_len < sizeof(struct sockaddr_l2tpip))
		return -EINVAL;
	if (addr->l2tp_family != AF_INET)
		return -EINVAL;

	lock_sock(sk);

	ret = -EINVAL;
	if (!sock_flag(sk, SOCK_ZAPPED))
		goto out;

	if (sk->sk_state != TCP_CLOSE)
		goto out;

	chk_addr_ret = inet_addr_type(net, addr->l2tp_addr.s_addr);
	ret = -EADDRNOTAVAIL;
	if (addr->l2tp_addr.s_addr && chk_addr_ret != RTN_LOCAL &&
	    chk_addr_ret != RTN_MULTICAST && chk_addr_ret != RTN_BROADCAST)
		goto out;

	if (addr->l2tp_addr.s_addr) {
		inet->inet_rcv_saddr = addr->l2tp_addr.s_addr;
		inet->inet_saddr = addr->l2tp_addr.s_addr;
	}
	if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST)
		inet->inet_saddr = 0;  /* Use device */

	write_lock_bh(&l2tp_ip_lock);
	if (__l2tp_ip_bind_lookup(net, addr->l2tp_addr.s_addr, 0,
				  sk->sk_bound_dev_if, addr->l2tp_conn_id)) {
		write_unlock_bh(&l2tp_ip_lock);
		ret = -EADDRINUSE;
		goto out;
	}

	sk_dst_reset(sk);
	l2tp_ip_sk(sk)->conn_id = addr->l2tp_conn_id;

	sk_add_bind_node(sk, &l2tp_ip_bind_table);
	sk_del_node_init(sk);
	write_unlock_bh(&l2tp_ip_lock);

	ret = 0;
	sock_reset_flag(sk, SOCK_ZAPPED);

out:
	release_sock(sk);

	return ret;
}

static int l2tp_ip_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
{
	struct sockaddr_l2tpip *lsa = (struct sockaddr_l2tpip *)uaddr;
	int rc;

	if (addr_len < sizeof(*lsa))
		return -EINVAL;

	if (ipv4_is_multicast(lsa->l2tp_addr.s_addr))
		return -EINVAL;

	lock_sock(sk);

	/* Must bind first - autobinding does not work */
	if (sock_flag(sk, SOCK_ZAPPED)) {
		rc = -EINVAL;
		goto out_sk;
	}

	rc = __ip4_datagram_connect(sk, uaddr, addr_len);
	if (rc < 0)
		goto out_sk;

	l2tp_ip_sk(sk)->peer_conn_id = lsa->l2tp_conn_id;

	write_lock_bh(&l2tp_ip_lock);
	hlist_del_init(&sk->sk_bind_node);
	sk_add_bind_node(sk, &l2tp_ip_bind_table);
	write_unlock_bh(&l2tp_ip_lock);

out_sk:
	release_sock(sk);

	return rc;
}

static int l2tp_ip_disconnect(struct sock *sk, int flags)
{
	if (sock_flag(sk, SOCK_ZAPPED))
		return 0;

	return __udp_disconnect(sk, flags);
}

static int l2tp_ip_getname(struct socket *sock, struct sockaddr *uaddr,
			   int peer)
{
	struct sock *sk		= sock->sk;
	struct inet_sock *inet	= inet_sk(sk);
	struct l2tp_ip_sock *lsk = l2tp_ip_sk(sk);
	struct sockaddr_l2tpip *lsa = (struct sockaddr_l2tpip *)uaddr;

	memset(lsa, 0, sizeof(*lsa));
	lsa->l2tp_family = AF_INET;
	if (peer) {
		if (!inet->inet_dport)
			return -ENOTCONN;
		lsa->l2tp_conn_id = lsk->peer_conn_id;
		lsa->l2tp_addr.s_addr = inet->inet_daddr;
	} else {
		__be32 addr = inet->inet_rcv_saddr;

		if (!addr)
			addr = inet->inet_saddr;
		lsa->l2tp_conn_id = lsk->conn_id;
		lsa->l2tp_addr.s_addr = addr;
	}
	return sizeof(*lsa);
}

static int l2tp_ip_backlog_recv(struct sock *sk, struct sk_buff *skb)
{
	int rc;

	/* Charge it to the socket, dropping if the queue is full. */
	rc = sock_queue_rcv_skb(sk, skb);
	if (rc < 0)
		goto drop;

	return 0;

drop:
	IP_INC_STATS(sock_net(sk), IPSTATS_MIB_INDISCARDS);
	kfree_skb(skb);
	return 0;
}

/* Userspace will call sendmsg() on the tunnel socket to send L2TP
 * control frames.
 */
static int l2tp_ip_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
{
	struct sk_buff *skb;
	int rc;
	struct inet_sock *inet = inet_sk(sk);
	struct rtable *rt = NULL;
	struct flowi4 *fl4;
	int connected = 0;
	__be32 daddr;

	lock_sock(sk);

	rc = -ENOTCONN;
	if (sock_flag(sk, SOCK_DEAD))
		goto out;

	/* Get and verify the address. */
	if (msg->msg_name) {
		DECLARE_SOCKADDR(struct sockaddr_l2tpip *, lip, msg->msg_name);

		rc = -EINVAL;
		if (msg->msg_namelen < sizeof(*lip))
			goto out;

		if (lip->l2tp_family != AF_INET) {
			rc = -EAFNOSUPPORT;
			if (lip->l2tp_family != AF_UNSPEC)
				goto out;
		}

		daddr = lip->l2tp_addr.s_addr;
	} else {
		rc = -EDESTADDRREQ;
		if (sk->sk_state != TCP_ESTABLISHED)
			goto out;

		daddr = inet->inet_daddr;
		connected = 1;
	}

	/* Allocate a socket buffer */
	rc = -ENOMEM;
	skb = sock_wmalloc(sk, 2 + NET_SKB_PAD + sizeof(struct iphdr) +
			   4 + len, 0, GFP_KERNEL);
	if (!skb)
		goto error;

	/* Reserve space for headers, putting IP header on 4-byte boundary. */
	skb_reserve(skb, 2 + NET_SKB_PAD);
	skb_reset_network_header(skb);
	skb_reserve(skb, sizeof(struct iphdr));
	skb_reset_transport_header(skb);

	/* Insert 0 session_id */
	*((__be32 *)skb_put(skb, 4)) = 0;

	/* Copy user data into skb */
	rc = memcpy_from_msg(skb_put(skb, len), msg, len);
	if (rc < 0) {
		kfree_skb(skb);
		goto error;
	}

	fl4 = &inet->cork.fl.u.ip4;
	if (connected)
		rt = (struct rtable *)__sk_dst_check(sk, 0);

	rcu_read_lock();
	if (!rt) {
		const struct ip_options_rcu *inet_opt;

		inet_opt = rcu_dereference(inet->inet_opt);

		/* Use correct destination address if we have options. */
		if (inet_opt && inet_opt->opt.srr)
			daddr = inet_opt->opt.faddr;

		/* If this fails, retransmit mechanism of transport layer will
		 * keep trying until route appears or the connection times
		 * itself out.
		 */
		rt = ip_route_output_ports(sock_net(sk), fl4, sk,
					   daddr, inet->inet_saddr,
					   inet->inet_dport, inet->inet_sport,
					   sk->sk_protocol, RT_CONN_FLAGS(sk),
					   sk->sk_bound_dev_if);
		if (IS_ERR(rt))
			goto no_route;
		if (connected) {
			sk_setup_caps(sk, &rt->dst);
		} else {
			skb_dst_set(skb, &rt->dst);
			goto xmit;
		}
	}

	/* We don't need to clone dst here, it is guaranteed to not disappear.
	 *  __dev_xmit_skb() might force a refcount if needed.
	 */
	skb_dst_set_noref(skb, &rt->dst);

xmit:
	/* Queue the packet to IP for output */
	rc = ip_queue_xmit(sk, skb, &inet->cork.fl);
	rcu_read_unlock();

error:
	if (rc >= 0)
		rc = len;

out:
	release_sock(sk);
	return rc;

no_route:
	rcu_read_unlock();
	IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTNOROUTES);
	kfree_skb(skb);
	rc = -EHOSTUNREACH;
	goto out;
}

static int l2tp_ip_recvmsg(struct sock *sk, struct msghdr *msg,
			   size_t len, int flags, int *addr_len)
{
	struct inet_sock *inet = inet_sk(sk);
	size_t copied = 0;
	int err = -EOPNOTSUPP;
	DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name);
	struct sk_buff *skb;

	if (flags & MSG_OOB)
		goto out;

	skb = skb_recv_datagram(sk, flags, &err);
	if (!skb)
		goto out;

	copied = skb->len;
	if (len < copied) {
		msg->msg_flags |= MSG_TRUNC;
		copied = len;
	}

	err = skb_copy_datagram_msg(skb, 0, msg, copied);
	if (err)
		goto done;

	sock_recv_timestamp(msg, sk, skb);

	/* Copy the address. */
	if (sin) {
		sin->sin_family = AF_INET;
		sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
		sin->sin_port = 0;
		memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
		*addr_len = sizeof(*sin);
	}
	if (inet->cmsg_flags)
		ip_cmsg_recv(msg, skb);
	if (flags & MSG_TRUNC)
		copied = skb->len;
done:
	skb_free_datagram(sk, skb);
out:
	return err ? err : copied;
}

int l2tp_ioctl(struct sock *sk, int cmd, unsigned long arg)
{
	struct sk_buff *skb;
	int amount;

	switch (cmd) {
	case SIOCOUTQ:
		amount = sk_wmem_alloc_get(sk);
		break;
	case SIOCINQ:
		spin_lock_bh(&sk->sk_receive_queue.lock);
		skb = skb_peek(&sk->sk_receive_queue);
		amount = skb ? skb->len : 0;
		spin_unlock_bh(&sk->sk_receive_queue.lock);
		break;

	default:
		return -ENOIOCTLCMD;
	}

	return put_user(amount, (int __user *)arg);
}
EXPORT_SYMBOL_GPL(l2tp_ioctl);

static struct proto l2tp_ip_prot = {
	.name		   = "L2TP/IP",
	.owner		   = THIS_MODULE,
	.init		   = l2tp_ip_open,
	.close		   = l2tp_ip_close,
	.bind		   = l2tp_ip_bind,
	.connect	   = l2tp_ip_connect,
	.disconnect	   = l2tp_ip_disconnect,
	.ioctl		   = l2tp_ioctl,
	.destroy	   = l2tp_ip_destroy_sock,
	.setsockopt	   = ip_setsockopt,
	.getsockopt	   = ip_getsockopt,
	.sendmsg	   = l2tp_ip_sendmsg,
	.recvmsg	   = l2tp_ip_recvmsg,
	.backlog_rcv	   = l2tp_ip_backlog_recv,
	.hash		   = l2tp_ip_hash,
	.unhash		   = l2tp_ip_unhash,
	.obj_size	   = sizeof(struct l2tp_ip_sock),
};

static const struct proto_ops l2tp_ip_ops = {
	.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	   = l2tp_ip_getname,
	.poll		   = datagram_poll,
	.ioctl		   = inet_ioctl,
	.gettstamp	   = sock_gettstamp,
	.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	   = sock_no_sendpage,
};

static struct inet_protosw l2tp_ip_protosw = {
	.type		= SOCK_DGRAM,
	.protocol	= IPPROTO_L2TP,
	.prot		= &l2tp_ip_prot,
	.ops		= &l2tp_ip_ops,
};

static struct net_protocol l2tp_ip_protocol __read_mostly = {
	.handler	= l2tp_ip_recv,
};

static int __init l2tp_ip_init(void)
{
	int err;

	pr_info("L2TP IP encapsulation support (L2TPv3)\n");

	err = proto_register(&l2tp_ip_prot, 1);
	if (err != 0)
		goto out;

	err = inet_add_protocol(&l2tp_ip_protocol, IPPROTO_L2TP);
	if (err)
		goto out1;

	inet_register_protosw(&l2tp_ip_protosw);
	return 0;

out1:
	proto_unregister(&l2tp_ip_prot);
out:
	return err;
}

static void __exit l2tp_ip_exit(void)
{
	inet_unregister_protosw(&l2tp_ip_protosw);
	inet_del_protocol(&l2tp_ip_protocol, IPPROTO_L2TP);
	proto_unregister(&l2tp_ip_prot);
}

module_init(l2tp_ip_init);
module_exit(l2tp_ip_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
MODULE_DESCRIPTION("L2TP over IP");
MODULE_VERSION("1.0");

/* Use the value of SOCK_DGRAM (2) directory, because __stringify doesn't like
 * enums
 */
MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET, 2, IPPROTO_L2TP);
MODULE_ALIAS_NET_PF_PROTO(PF_INET, IPPROTO_L2TP);
Commit	Line	Data
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
20dcb110	2	/* L2TPv3 IP encapsulation support
0d76751f JC	3	*
0d76751f JC	4	* Copyright (c) 2008,2009,2010 Katalix Systems Ltd
0d76751f JC	5	*/
0d76751f JC	6
a4ca44fa JP	7	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
a4ca44fa JP	8
72fb96e7	9	#include <asm/ioctls.h>
0d76751f JC	10	#include <linux/icmp.h>
	11	#include <linux/module.h>
	12	#include <linux/skbuff.h>
	13	#include <linux/random.h>
	14	#include <linux/socket.h>
	15	#include <linux/l2tp.h>
	16	#include <linux/in.h>
	17	#include <net/sock.h>
	18	#include <net/ip.h>
	19	#include <net/icmp.h>
	20	#include <net/udp.h>
	21	#include <net/inet_common.h>
0d76751f JC	22	#include <net/tcp_states.h>
	23	#include <net/protocol.h>
	24	#include <net/xfrm.h>
	25
	26	#include "l2tp_core.h"
	27
	28	struct l2tp_ip_sock {
	29	/* inet_sock has to be the first member of l2tp_ip_sock */
	30	struct inet_sock inet;
	31
c8657fd5 JC	32	u32 conn_id;
c8657fd5 JC	33	u32 peer_conn_id;
0d76751f JC	34	};
	35
	36	static DEFINE_RWLOCK(l2tp_ip_lock);
	37	static struct hlist_head l2tp_ip_table;
	38	static struct hlist_head l2tp_ip_bind_table;
	39
	40	static inline struct l2tp_ip_sock l2tp_ip_sk(const struct sock sk)
	41	{
	42	return (struct l2tp_ip_sock *)sk;
	43	}
	44
a9b2dff8 GN	45	static struct sock __l2tp_ip_bind_lookup(const struct net net, __be32 laddr,
a9b2dff8 GN	46	__be32 raddr, int dif, u32 tunnel_id)
0d76751f	47	{
0d76751f JC	48	struct sock *sk;
0d76751f JC	49
b67bfe0d	50	sk_for_each_bound(sk, &l2tp_ip_bind_table) {
bb39b0bd GN	51	const struct l2tp_ip_sock *l2tp = l2tp_ip_sk(sk);
bb39b0bd GN	52	const struct inet_sock *inet = inet_sk(sk);
ff009403	53	int bound_dev_if;
0d76751f	54
c5fdae04 GN	55	if (!net_eq(sock_net(sk), net))
	56	continue;
	57
ff009403 ED	58	bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
ff009403 ED	59	if (bound_dev_if && dif && bound_dev_if != dif)
c5fdae04 GN	60	continue;
	61
	62	if (inet->inet_rcv_saddr && laddr &&
	63	inet->inet_rcv_saddr != laddr)
	64	continue;
	65
	66	if (inet->inet_daddr && raddr && inet->inet_daddr != raddr)
	67	continue;
	68
	69	if (l2tp->conn_id != tunnel_id)
	70	continue;
	71
	72	goto found;
0d76751f JC	73	}
	74
	75	sk = NULL;
	76	found:
	77	return sk;
	78	}
	79
0d76751f JC	80	/* When processing receive frames, there are two cases to
	81	* consider. Data frames consist of a non-zero session-id and an
	82	* optional cookie. Control frames consist of a regular L2TP header
	83	* preceded by 32-bits of zeros.
	84	*
	85	* L2TPv3 Session Header Over IP
	86	*
	87	* 0 1 2 3
	88	* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	89	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	90	* \| Session ID \|
	91	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	92	* \| Cookie (optional, maximum 64 bits)...
	93	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	94	* \|
	95	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	96	*
	97	* L2TPv3 Control Message Header Over IP
	98	*
	99	* 0 1 2 3
	100	* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	101	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	102	* \| (32 bits of zeros) \|
	103	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	104	* \|T\|L\|x\|x\|S\|x\|x\|x\|x\|x\|x\|x\| Ver \| Length \|
	105	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	106	* \| Control Connection ID \|
	107	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	108	* \| Ns \| Nr \|
	109	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	110	*
	111	* All control frames are passed to userspace.
	112	*/
	113	static int l2tp_ip_recv(struct sk_buff *skb)
	114	{
9d6ddb19	115	struct net *net = dev_net(skb->dev);
0d76751f JC	116	struct sock *sk;
	117	u32 session_id;
	118	u32 tunnel_id;
	119	unsigned char ptr, optr;
	120	struct l2tp_session *session;
	121	struct l2tp_tunnel *tunnel = NULL;
8f7dc9ae	122	struct iphdr *iph;
0d76751f	123
0d76751f JC	124	if (!pskb_may_pull(skb, 4))
	125	goto discard;
	126
5745b823	127	/* Point to L2TP header */
95075150 TP	128	optr = skb->data;
95075150 TP	129	ptr = skb->data;
b71a61cc	130	session_id = ntohl(((__be32 )ptr));
0d76751f JC	131	ptr += 4;
	132
	133	/* RFC3931: L2TP/IP packets have the first 4 bytes containing
	134	* the session_id. If it is 0, the packet is a L2TP control
	135	* frame and the session_id value can be discarded.
	136	*/
	137	if (session_id == 0) {
	138	__skb_pull(skb, 4);
	139	goto pass_up;
	140	}
	141
	142	/* Ok, this is a data packet. Lookup the session. */
01e28b92	143	session = l2tp_session_get(net, session_id);
61b9a047	144	if (!session)
0d76751f JC	145	goto discard;
	146
	147	tunnel = session->tunnel;
61b9a047 GN	148	if (!tunnel)
61b9a047 GN	149	goto discard_sess;
0d76751f	150
4522a70d JW	151	if (l2tp_v3_ensure_opt_in_linear(session, skb, &ptr, &optr))
	152	goto discard_sess;
	153
2b139e6b	154	l2tp_recv_common(session, skb, ptr, optr, 0, skb->len);
61b9a047	155	l2tp_session_dec_refcount(session);
0d76751f JC	156
	157	return 0;
	158
	159	pass_up:
	160	/* Get the tunnel_id from the L2TP header */
	161	if (!pskb_may_pull(skb, 12))
	162	goto discard;
	163
	164	if ((skb->data[0] & 0xc0) != 0xc0)
	165	goto discard;
	166
b71a61cc	167	tunnel_id = ntohl((__be32 )&skb->data[4]);
8f7dc9ae GN	168	iph = (struct iphdr *)skb_network_header(skb);
	169
	170	read_lock_bh(&l2tp_ip_lock);
	171	sk = __l2tp_ip_bind_lookup(net, iph->daddr, iph->saddr, inet_iif(skb),
	172	tunnel_id);
	173	if (!sk) {
0d76751f	174	read_unlock_bh(&l2tp_ip_lock);
8f7dc9ae	175	goto discard;
0d76751f	176	}
8f7dc9ae GN	177	sock_hold(sk);
8f7dc9ae GN	178	read_unlock_bh(&l2tp_ip_lock);
0d76751f	179
0d76751f JC	180	if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb))
	181	goto discard_put;
	182
895b5c9f	183	nf_reset_ct(skb);
0d76751f JC	184
	185	return sk_receive_skb(sk, skb, 1);
	186
61b9a047	187	discard_sess:
61b9a047 GN	188	l2tp_session_dec_refcount(session);
	189	goto discard;
	190
0d76751f JC	191	discard_put:
	192	sock_put(sk);
	193
	194	discard:
	195	kfree_skb(skb);
	196	return 0;
	197	}
	198
02c71b14	199	static int l2tp_ip_hash(struct sock *sk)
0d76751f	200	{
02c71b14 ED	201	if (sk_unhashed(sk)) {
	202	write_lock_bh(&l2tp_ip_lock);
	203	sk_add_node(sk, &l2tp_ip_table);
	204	write_unlock_bh(&l2tp_ip_lock);
	205	}
	206	return 0;
	207	}
0d76751f	208
02c71b14 ED	209	static void l2tp_ip_unhash(struct sock *sk)
	210	{
	211	if (sk_unhashed(sk))
	212	return;
0d76751f	213	write_lock_bh(&l2tp_ip_lock);
02c71b14	214	sk_del_node_init(sk);
0d76751f	215	write_unlock_bh(&l2tp_ip_lock);
02c71b14 ED	216	}
	217
	218	static int l2tp_ip_open(struct sock *sk)
	219	{
	220	/* Prevent autobind. We don't have ports. */
	221	inet_sk(sk)->inet_num = IPPROTO_L2TP;
0d76751f	222
02c71b14	223	l2tp_ip_hash(sk);
0d76751f JC	224	return 0;
	225	}
	226
	227	static void l2tp_ip_close(struct sock *sk, long timeout)
	228	{
	229	write_lock_bh(&l2tp_ip_lock);
	230	hlist_del_init(&sk->sk_bind_node);
d1f224ae	231	sk_del_node_init(sk);
0d76751f JC	232	write_unlock_bh(&l2tp_ip_lock);
	233	sk_common_release(sk);
	234	}
	235
	236	static void l2tp_ip_destroy_sock(struct sock *sk)
	237	{
45faeff1	238	struct l2tp_tunnel *tunnel = l2tp_sk_to_tunnel(sk);
0d76751f JC	239	struct sk_buff *skb;
	240
	241	while ((skb = __skb_dequeue_tail(&sk->sk_write_queue)) != NULL)
	242	kfree_skb(skb);
	243
d00fa9ad JC	244	if (tunnel)
d00fa9ad JC	245	l2tp_tunnel_delete(tunnel);
0d76751f JC	246	}
	247
	248	static int l2tp_ip_bind(struct sock sk, struct sockaddr uaddr, int addr_len)
	249	{
	250	struct inet_sock *inet = inet_sk(sk);
b71a61cc	251	struct sockaddr_l2tpip addr = (struct sockaddr_l2tpip )uaddr;
9d6ddb19	252	struct net *net = sock_net(sk);
c51ce497	253	int ret;
0d76751f JC	254	int chk_addr_ret;
0d76751f JC	255
c51ce497 JC	256	if (addr_len < sizeof(struct sockaddr_l2tpip))
	257	return -EINVAL;
	258	if (addr->l2tp_family != AF_INET)
	259	return -EINVAL;
	260
0d76751f	261	lock_sock(sk);
d5e3a190 GN	262
d5e3a190 GN	263	ret = -EINVAL;
32c23116 GN	264	if (!sock_flag(sk, SOCK_ZAPPED))
	265	goto out;
	266
8cf2f704	267	if (sk->sk_state != TCP_CLOSE)
0d76751f JC	268	goto out;
0d76751f JC	269
9d6ddb19	270	chk_addr_ret = inet_addr_type(net, addr->l2tp_addr.s_addr);
0d76751f JC	271	ret = -EADDRNOTAVAIL;
	272	if (addr->l2tp_addr.s_addr && chk_addr_ret != RTN_LOCAL &&
	273	chk_addr_ret != RTN_MULTICAST && chk_addr_ret != RTN_BROADCAST)
	274	goto out;
	275
95075150 TP	276	if (addr->l2tp_addr.s_addr) {
	277	inet->inet_rcv_saddr = addr->l2tp_addr.s_addr;
	278	inet->inet_saddr = addr->l2tp_addr.s_addr;
	279	}
0d76751f JC	280	if (chk_addr_ret == RTN_MULTICAST \|\| chk_addr_ret == RTN_BROADCAST)
0d76751f JC	281	inet->inet_saddr = 0; /* Use device */
0d76751f	282
d5e3a190	283	write_lock_bh(&l2tp_ip_lock);
a9b2dff8	284	if (__l2tp_ip_bind_lookup(net, addr->l2tp_addr.s_addr, 0,
d5e3a190 GN	285	sk->sk_bound_dev_if, addr->l2tp_conn_id)) {
	286	write_unlock_bh(&l2tp_ip_lock);
	287	ret = -EADDRINUSE;
	288	goto out;
	289	}
	290
	291	sk_dst_reset(sk);
0d76751f JC	292	l2tp_ip_sk(sk)->conn_id = addr->l2tp_conn_id;
0d76751f JC	293
0d76751f JC	294	sk_add_bind_node(sk, &l2tp_ip_bind_table);
	295	sk_del_node_init(sk);
	296	write_unlock_bh(&l2tp_ip_lock);
d5e3a190	297
0d76751f	298	ret = 0;
c51ce497 JC	299	sock_reset_flag(sk, SOCK_ZAPPED);
c51ce497 JC	300
0d76751f JC	301	out:
	302	release_sock(sk);
	303
0d76751f JC	304	return ret;
	305	}
	306
	307	static int l2tp_ip_connect(struct sock sk, struct sockaddr uaddr, int addr_len)
	308	{
b71a61cc	309	struct sockaddr_l2tpip lsa = (struct sockaddr_l2tpip )uaddr;
de3c7a18	310	int rc;
0d76751f	311
0d76751f	312	if (addr_len < sizeof(*lsa))
de3c7a18	313	return -EINVAL;
2f16270f	314
0d76751f	315	if (ipv4_is_multicast(lsa->l2tp_addr.s_addr))
de3c7a18	316	return -EINVAL;
0d76751f	317
de3c7a18	318	lock_sock(sk);
0d76751f	319
0382a25a GN	320	/* Must bind first - autobinding does not work */
	321	if (sock_flag(sk, SOCK_ZAPPED)) {
	322	rc = -EINVAL;
	323	goto out_sk;
	324	}
	325
	326	rc = __ip4_datagram_connect(sk, uaddr, addr_len);
	327	if (rc < 0)
	328	goto out_sk;
	329
0d76751f JC	330	l2tp_ip_sk(sk)->peer_conn_id = lsa->l2tp_conn_id;
0d76751f JC	331
0d76751f JC	332	write_lock_bh(&l2tp_ip_lock);
	333	hlist_del_init(&sk->sk_bind_node);
	334	sk_add_bind_node(sk, &l2tp_ip_bind_table);
	335	write_unlock_bh(&l2tp_ip_lock);
	336
0382a25a	337	out_sk:
2f16270f	338	release_sock(sk);
0382a25a	339
0d76751f JC	340	return rc;
	341	}
	342
c51ce497 JC	343	static int l2tp_ip_disconnect(struct sock *sk, int flags)
	344	{
	345	if (sock_flag(sk, SOCK_ZAPPED))
	346	return 0;
	347
286c72de	348	return __udp_disconnect(sk, flags);
c51ce497 JC	349	}
c51ce497 JC	350
0d76751f	351	static int l2tp_ip_getname(struct socket sock, struct sockaddr uaddr,
9b2c45d4	352	int peer)
0d76751f JC	353	{
	354	struct sock *sk = sock->sk;
	355	struct inet_sock *inet = inet_sk(sk);
	356	struct l2tp_ip_sock *lsk = l2tp_ip_sk(sk);
	357	struct sockaddr_l2tpip lsa = (struct sockaddr_l2tpip )uaddr;
	358
	359	memset(lsa, 0, sizeof(*lsa));
	360	lsa->l2tp_family = AF_INET;
	361	if (peer) {
	362	if (!inet->inet_dport)
	363	return -ENOTCONN;
	364	lsa->l2tp_conn_id = lsk->peer_conn_id;
	365	lsa->l2tp_addr.s_addr = inet->inet_daddr;
	366	} else {
	367	__be32 addr = inet->inet_rcv_saddr;
b71a61cc	368
0d76751f JC	369	if (!addr)
	370	addr = inet->inet_saddr;
	371	lsa->l2tp_conn_id = lsk->conn_id;
	372	lsa->l2tp_addr.s_addr = addr;
	373	}
9b2c45d4	374	return sizeof(*lsa);
0d76751f JC	375	}
	376
	377	static int l2tp_ip_backlog_recv(struct sock sk, struct sk_buff skb)
	378	{
	379	int rc;
	380
0d76751f JC	381	/* Charge it to the socket, dropping if the queue is full. */
	382	rc = sock_queue_rcv_skb(sk, skb);
	383	if (rc < 0)
	384	goto drop;
	385
	386	return 0;
	387
	388	drop:
9d6ddb19	389	IP_INC_STATS(sock_net(sk), IPSTATS_MIB_INDISCARDS);
0d76751f	390	kfree_skb(skb);
51fb60eb	391	return 0;
0d76751f JC	392	}
	393
	394	/* Userspace will call sendmsg() on the tunnel socket to send L2TP
	395	* control frames.
	396	*/
1b784140	397	static int l2tp_ip_sendmsg(struct sock sk, struct msghdr msg, size_t len)
0d76751f JC	398	{
	399	struct sk_buff *skb;
	400	int rc;
0d76751f	401	struct inet_sock *inet = inet_sk(sk);
0d76751f	402	struct rtable *rt = NULL;
fdbb0f07	403	struct flowi4 *fl4;
0d76751f JC	404	int connected = 0;
	405	__be32 daddr;
	406
2f16270f DM	407	lock_sock(sk);
	408
	409	rc = -ENOTCONN;
0d76751f	410	if (sock_flag(sk, SOCK_DEAD))
2f16270f	411	goto out;
0d76751f JC	412
	413	/* Get and verify the address. */
	414	if (msg->msg_name) {
342dfc30	415	DECLARE_SOCKADDR(struct sockaddr_l2tpip *, lip, msg->msg_name);
b71a61cc	416
2f16270f	417	rc = -EINVAL;
0d76751f	418	if (msg->msg_namelen < sizeof(*lip))
2f16270f	419	goto out;
0d76751f JC	420
0d76751f JC	421	if (lip->l2tp_family != AF_INET) {
2f16270f	422	rc = -EAFNOSUPPORT;
0d76751f	423	if (lip->l2tp_family != AF_UNSPEC)
2f16270f	424	goto out;
0d76751f JC	425	}
	426
	427	daddr = lip->l2tp_addr.s_addr;
	428	} else {
84768edb	429	rc = -EDESTADDRREQ;
0d76751f	430	if (sk->sk_state != TCP_ESTABLISHED)
84768edb	431	goto out;
0d76751f JC	432
	433	daddr = inet->inet_daddr;
	434	connected = 1;
	435	}
	436
	437	/* Allocate a socket buffer */
	438	rc = -ENOMEM;
	439	skb = sock_wmalloc(sk, 2 + NET_SKB_PAD + sizeof(struct iphdr) +
	440	4 + len, 0, GFP_KERNEL);
	441	if (!skb)
	442	goto error;
	443
	444	/* Reserve space for headers, putting IP header on 4-byte boundary. */
	445	skb_reserve(skb, 2 + NET_SKB_PAD);
	446	skb_reset_network_header(skb);
	447	skb_reserve(skb, sizeof(struct iphdr));
	448	skb_reset_transport_header(skb);
	449
	450	/* Insert 0 session_id */
b71a61cc	451	((__be32 )skb_put(skb, 4)) = 0;
0d76751f JC	452
0d76751f JC	453	/* Copy user data into skb */
6ce8e9ce	454	rc = memcpy_from_msg(skb_put(skb, len), msg, len);
0d76751f JC	455	if (rc < 0) {
	456	kfree_skb(skb);
	457	goto error;
	458	}
	459
fdbb0f07	460	fl4 = &inet->cork.fl.u.ip4;
0d76751f	461	if (connected)
b71a61cc	462	rt = (struct rtable *)__sk_dst_check(sk, 0);
0d76751f	463
081b1b1b	464	rcu_read_lock();
0febc7b3	465	if (!rt) {
081b1b1b	466	const struct ip_options_rcu *inet_opt;
f6d8bd05	467
778865a5	468	inet_opt = rcu_dereference(inet->inet_opt);
f6d8bd05	469
0d76751f	470	/* Use correct destination address if we have options. */
f6d8bd05 ED	471	if (inet_opt && inet_opt->opt.srr)
f6d8bd05 ED	472	daddr = inet_opt->opt.faddr;
0d76751f	473
78fbfd8a DM	474	/* If this fails, retransmit mechanism of transport layer will
	475	* keep trying until route appears or the connection times
	476	* itself out.
	477	*/
fdbb0f07	478	rt = ip_route_output_ports(sock_net(sk), fl4, sk,
78fbfd8a DM	479	daddr, inet->inet_saddr,
	480	inet->inet_dport, inet->inet_sport,
	481	sk->sk_protocol, RT_CONN_FLAGS(sk),
	482	sk->sk_bound_dev_if);
	483	if (IS_ERR(rt))
	484	goto no_route;
4399a4df	485	if (connected) {
081b1b1b	486	sk_setup_caps(sk, &rt->dst);
4399a4df ED	487	} else {
	488	skb_dst_set(skb, &rt->dst);
	489	goto xmit;
	490	}
0d76751f	491	}
081b1b1b	492
7f553ff2	493	/* We don't need to clone dst here, it is guaranteed to not disappear.
081b1b1b ED	494	* __dev_xmit_skb() might force a refcount if needed.
	495	*/
	496	skb_dst_set_noref(skb, &rt->dst);
0d76751f	497
4399a4df	498	xmit:
0d76751f	499	/* Queue the packet to IP for output */
b0270e91	500	rc = ip_queue_xmit(sk, skb, &inet->cork.fl);
081b1b1b	501	rcu_read_unlock();
0d76751f JC	502
0d76751f JC	503	error:
c8657fd5	504	if (rc >= 0)
0d76751f	505	rc = len;
0d76751f	506
2f16270f DM	507	out:
2f16270f DM	508	release_sock(sk);
0d76751f JC	509	return rc;
	510
	511	no_route:
081b1b1b	512	rcu_read_unlock();
0d76751f JC	513	IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTNOROUTES);
0d76751f JC	514	kfree_skb(skb);
2f16270f DM	515	rc = -EHOSTUNREACH;
2f16270f DM	516	goto out;
0d76751f JC	517	}
0d76751f JC	518
1b784140	519	static int l2tp_ip_recvmsg(struct sock sk, struct msghdr msg,
ec095263	520	size_t len, int flags, int *addr_len)
0d76751f JC	521	{
0d76751f JC	522	struct inet_sock *inet = inet_sk(sk);
0d76751f JC	523	size_t copied = 0;
0d76751f JC	524	int err = -EOPNOTSUPP;
342dfc30	525	DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name);
0d76751f JC	526	struct sk_buff *skb;
	527
	528	if (flags & MSG_OOB)
	529	goto out;
	530
f4b41f06	531	skb = skb_recv_datagram(sk, flags, &err);
0d76751f JC	532	if (!skb)
	533	goto out;
	534
	535	copied = skb->len;
	536	if (len < copied) {
	537	msg->msg_flags \|= MSG_TRUNC;
	538	copied = len;
	539	}
	540
51f3d02b	541	err = skb_copy_datagram_msg(skb, 0, msg, copied);
0d76751f JC	542	if (err)
	543	goto done;
	544
	545	sock_recv_timestamp(msg, sk, skb);
	546
	547	/* Copy the address. */
	548	if (sin) {
	549	sin->sin_family = AF_INET;
	550	sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
	551	sin->sin_port = 0;
	552	memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
bceaa902	553	addr_len = sizeof(sin);
0d76751f JC	554	}
	555	if (inet->cmsg_flags)
	556	ip_cmsg_recv(msg, skb);
	557	if (flags & MSG_TRUNC)
	558	copied = skb->len;
	559	done:
	560	skb_free_datagram(sk, skb);
	561	out:
c8657fd5	562	return err ? err : copied;
0d76751f JC	563	}
0d76751f JC	564
72fb96e7 ED	565	int l2tp_ioctl(struct sock *sk, int cmd, unsigned long arg)
	566	{
	567	struct sk_buff *skb;
	568	int amount;
	569
	570	switch (cmd) {
	571	case SIOCOUTQ:
	572	amount = sk_wmem_alloc_get(sk);
	573	break;
	574	case SIOCINQ:
	575	spin_lock_bh(&sk->sk_receive_queue.lock);
	576	skb = skb_peek(&sk->sk_receive_queue);
	577	amount = skb ? skb->len : 0;
	578	spin_unlock_bh(&sk->sk_receive_queue.lock);
	579	break;
	580
	581	default:
	582	return -ENOIOCTLCMD;
	583	}
	584
	585	return put_user(amount, (int __user *)arg);
	586	}
ca7885db	587	EXPORT_SYMBOL_GPL(l2tp_ioctl);
72fb96e7	588
fc130840	589	static struct proto l2tp_ip_prot = {
0d76751f JC	590	.name = "L2TP/IP",
	591	.owner = THIS_MODULE,
	592	.init = l2tp_ip_open,
	593	.close = l2tp_ip_close,
	594	.bind = l2tp_ip_bind,
	595	.connect = l2tp_ip_connect,
c51ce497	596	.disconnect = l2tp_ip_disconnect,
72fb96e7	597	.ioctl = l2tp_ioctl,
0d76751f JC	598	.destroy = l2tp_ip_destroy_sock,
	599	.setsockopt = ip_setsockopt,
	600	.getsockopt = ip_getsockopt,
	601	.sendmsg = l2tp_ip_sendmsg,
	602	.recvmsg = l2tp_ip_recvmsg,
	603	.backlog_rcv = l2tp_ip_backlog_recv,
02c71b14 ED	604	.hash = l2tp_ip_hash,
02c71b14 ED	605	.unhash = l2tp_ip_unhash,
0d76751f	606	.obj_size = sizeof(struct l2tp_ip_sock),
0d76751f JC	607	};
	608
	609	static const struct proto_ops l2tp_ip_ops = {
	610	.family = PF_INET,
	611	.owner = THIS_MODULE,
	612	.release = inet_release,
	613	.bind = inet_bind,
	614	.connect = inet_dgram_connect,
	615	.socketpair = sock_no_socketpair,
	616	.accept = sock_no_accept,
	617	.getname = l2tp_ip_getname,
a11e1d43	618	.poll = datagram_poll,
0d76751f	619	.ioctl = inet_ioctl,
c7cbdbf2	620	.gettstamp = sock_gettstamp,
0d76751f JC	621	.listen = sock_no_listen,
	622	.shutdown = inet_shutdown,
	623	.setsockopt = sock_common_setsockopt,
	624	.getsockopt = sock_common_getsockopt,
	625	.sendmsg = inet_sendmsg,
	626	.recvmsg = sock_common_recvmsg,
	627	.mmap = sock_no_mmap,
	628	.sendpage = sock_no_sendpage,
0d76751f JC	629	};
	630
	631	static struct inet_protosw l2tp_ip_protosw = {
	632	.type = SOCK_DGRAM,
	633	.protocol = IPPROTO_L2TP,
	634	.prot = &l2tp_ip_prot,
	635	.ops = &l2tp_ip_ops,
0d76751f JC	636	};
	637
	638	static struct net_protocol l2tp_ip_protocol __read_mostly = {
	639	.handler = l2tp_ip_recv,
	640	};
	641
	642	static int __init l2tp_ip_init(void)
	643	{
	644	int err;
	645
a4ca44fa	646	pr_info("L2TP IP encapsulation support (L2TPv3)\n");
0d76751f JC	647
	648	err = proto_register(&l2tp_ip_prot, 1);
	649	if (err != 0)
	650	goto out;
	651
	652	err = inet_add_protocol(&l2tp_ip_protocol, IPPROTO_L2TP);
	653	if (err)
	654	goto out1;
	655
	656	inet_register_protosw(&l2tp_ip_protosw);
	657	return 0;
	658
	659	out1:
	660	proto_unregister(&l2tp_ip_prot);
	661	out:
	662	return err;
	663	}
	664
	665	static void __exit l2tp_ip_exit(void)
	666	{
	667	inet_unregister_protosw(&l2tp_ip_protosw);
	668	inet_del_protocol(&l2tp_ip_protocol, IPPROTO_L2TP);
	669	proto_unregister(&l2tp_ip_prot);
	670	}
	671
	672	module_init(l2tp_ip_init);
	673	module_exit(l2tp_ip_exit);
	674
	675	MODULE_LICENSE("GPL");
	676	MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
	677	MODULE_DESCRIPTION("L2TP over IP");
	678	MODULE_VERSION("1.0");
e8d34a88	679
e9c54999	680	/* Use the value of SOCK_DGRAM (2) directory, because __stringify doesn't like
e8d34a88 MM	681	* enums
	682	*/
	683	MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET, 2, IPPROTO_L2TP);
163c2e25	684	MODULE_ALIAS_NET_PF_PROTO(PF_INET, IPPROTO_L2TP);