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@@ -0,0 +1,679 @@
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+/*
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+ * L2TPv3 IP encapsulation support
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+ *
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+ * Copyright (c) 2008,2009,2010 Katalix Systems Ltd
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+ *
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+ * This program is free software; you can redistribute it and/or
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+ * modify it under the terms of the GNU General Public License
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+ * as published by the Free Software Foundation; either version
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+ * 2 of the License, or (at your option) any later version.
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+ */
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+
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+#include <linux/icmp.h>
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+#include <linux/module.h>
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+#include <linux/skbuff.h>
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+#include <linux/random.h>
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+#include <linux/socket.h>
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+#include <linux/l2tp.h>
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+#include <linux/in.h>
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+#include <net/sock.h>
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+#include <net/ip.h>
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+#include <net/icmp.h>
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+#include <net/udp.h>
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+#include <net/inet_common.h>
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+#include <net/inet_hashtables.h>
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+#include <net/tcp_states.h>
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+#include <net/protocol.h>
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+#include <net/xfrm.h>
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+
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+#include "l2tp_core.h"
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+
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+struct l2tp_ip_sock {
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+ /* inet_sock has to be the first member of l2tp_ip_sock */
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+ struct inet_sock inet;
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+
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+ __u32 conn_id;
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+ __u32 peer_conn_id;
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+
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+ __u64 tx_packets;
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+ __u64 tx_bytes;
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+ __u64 tx_errors;
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+ __u64 rx_packets;
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+ __u64 rx_bytes;
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+ __u64 rx_errors;
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+};
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+
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+static DEFINE_RWLOCK(l2tp_ip_lock);
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+static struct hlist_head l2tp_ip_table;
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+static struct hlist_head l2tp_ip_bind_table;
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+
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+static inline struct l2tp_ip_sock *l2tp_ip_sk(const struct sock *sk)
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+{
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+ return (struct l2tp_ip_sock *)sk;
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+}
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+
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+static struct sock *__l2tp_ip_bind_lookup(struct net *net, __be32 laddr, int dif, u32 tunnel_id)
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+{
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+ struct hlist_node *node;
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+ struct sock *sk;
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+
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+ sk_for_each_bound(sk, node, &l2tp_ip_bind_table) {
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+ struct inet_sock *inet = inet_sk(sk);
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+ struct l2tp_ip_sock *l2tp = l2tp_ip_sk(sk);
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+
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+ if (l2tp == NULL)
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+ continue;
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+
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+ if ((l2tp->conn_id == tunnel_id) &&
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+#ifdef CONFIG_NET_NS
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+ (sk->sk_net == net) &&
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+#endif
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+ !(inet->inet_rcv_saddr && inet->inet_rcv_saddr != laddr) &&
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+ !(sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif))
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+ goto found;
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+ }
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+
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+ sk = NULL;
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+found:
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+ return sk;
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+}
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+
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+static inline struct sock *l2tp_ip_bind_lookup(struct net *net, __be32 laddr, int dif, u32 tunnel_id)
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+{
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+ struct sock *sk = __l2tp_ip_bind_lookup(net, laddr, dif, tunnel_id);
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+ if (sk)
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+ sock_hold(sk);
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+
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+ return sk;
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+}
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+
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+/* When processing receive frames, there are two cases to
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+ * consider. Data frames consist of a non-zero session-id and an
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+ * optional cookie. Control frames consist of a regular L2TP header
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+ * preceded by 32-bits of zeros.
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+ *
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+ * L2TPv3 Session Header Over IP
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+ *
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+ * 0 1 2 3
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+ * 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
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+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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+ * | Session ID |
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+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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+ * | Cookie (optional, maximum 64 bits)...
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+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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+ * |
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+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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+ *
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+ * L2TPv3 Control Message Header Over IP
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+ *
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+ * 0 1 2 3
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+ * 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
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+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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+ * | (32 bits of zeros) |
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+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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+ * |T|L|x|x|S|x|x|x|x|x|x|x| Ver | Length |
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+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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+ * | Control Connection ID |
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+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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+ * | Ns | Nr |
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+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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+ *
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+ * All control frames are passed to userspace.
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+ */
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+static int l2tp_ip_recv(struct sk_buff *skb)
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+{
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+ struct sock *sk;
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+ u32 session_id;
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+ u32 tunnel_id;
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+ unsigned char *ptr, *optr;
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+ struct l2tp_session *session;
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+ struct l2tp_tunnel *tunnel = NULL;
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+ int length;
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+ int offset;
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+
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+ /* Point to L2TP header */
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+ optr = ptr = skb->data;
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+
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+ if (!pskb_may_pull(skb, 4))
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+ goto discard;
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+
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+ session_id = ntohl(*((__be32 *) ptr));
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+ ptr += 4;
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+
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+ /* RFC3931: L2TP/IP packets have the first 4 bytes containing
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+ * the session_id. If it is 0, the packet is a L2TP control
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+ * frame and the session_id value can be discarded.
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+ */
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+ if (session_id == 0) {
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+ __skb_pull(skb, 4);
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+ goto pass_up;
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+ }
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+
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+ /* Ok, this is a data packet. Lookup the session. */
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+ session = l2tp_session_find(&init_net, NULL, session_id);
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+ if (session == NULL)
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+ goto discard;
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+
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+ tunnel = session->tunnel;
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+ if (tunnel == NULL)
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+ goto discard;
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+
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+ /* Trace packet contents, if enabled */
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+ if (tunnel->debug & L2TP_MSG_DATA) {
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+ length = min(32u, skb->len);
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+ if (!pskb_may_pull(skb, length))
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+ goto discard;
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+
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+ printk(KERN_DEBUG "%s: ip recv: ", tunnel->name);
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+
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+ offset = 0;
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+ do {
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+ printk(" %02X", ptr[offset]);
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+ } while (++offset < length);
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+
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+ printk("\n");
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+ }
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+
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+ l2tp_recv_common(session, skb, ptr, optr, 0, skb->len, tunnel->recv_payload_hook);
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+
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+ return 0;
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+
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+pass_up:
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+ /* Get the tunnel_id from the L2TP header */
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+ if (!pskb_may_pull(skb, 12))
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+ goto discard;
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+
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+ if ((skb->data[0] & 0xc0) != 0xc0)
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+ goto discard;
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+
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+ tunnel_id = ntohl(*(__be32 *) &skb->data[4]);
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+ tunnel = l2tp_tunnel_find(&init_net, tunnel_id);
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+ if (tunnel != NULL)
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+ sk = tunnel->sock;
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+ else {
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+ struct iphdr *iph = (struct iphdr *) skb_network_header(skb);
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+
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+ read_lock_bh(&l2tp_ip_lock);
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+ sk = __l2tp_ip_bind_lookup(&init_net, iph->daddr, 0, tunnel_id);
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+ read_unlock_bh(&l2tp_ip_lock);
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+ }
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+
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+ if (sk == NULL)
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+ goto discard;
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+
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+ sock_hold(sk);
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+
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+ if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb))
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+ goto discard_put;
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+
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+ nf_reset(skb);
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+
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+ return sk_receive_skb(sk, skb, 1);
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+
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+discard_put:
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+ sock_put(sk);
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+
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+discard:
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+ kfree_skb(skb);
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+ return 0;
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+}
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+
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+static int l2tp_ip_open(struct sock *sk)
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+{
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+ /* Prevent autobind. We don't have ports. */
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+ inet_sk(sk)->inet_num = IPPROTO_L2TP;
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+
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+ write_lock_bh(&l2tp_ip_lock);
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+ sk_add_node(sk, &l2tp_ip_table);
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+ write_unlock_bh(&l2tp_ip_lock);
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+
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+ return 0;
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+}
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+
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+static void l2tp_ip_close(struct sock *sk, long timeout)
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+{
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+ write_lock_bh(&l2tp_ip_lock);
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+ hlist_del_init(&sk->sk_bind_node);
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+ hlist_del_init(&sk->sk_node);
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+ write_unlock_bh(&l2tp_ip_lock);
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+ sk_common_release(sk);
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+}
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+
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+static void l2tp_ip_destroy_sock(struct sock *sk)
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+{
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+ struct sk_buff *skb;
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+
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+ while ((skb = __skb_dequeue_tail(&sk->sk_write_queue)) != NULL)
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+ kfree_skb(skb);
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+
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+ sk_refcnt_debug_dec(sk);
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+}
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+
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+static int l2tp_ip_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
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+{
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+ struct inet_sock *inet = inet_sk(sk);
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+ struct sockaddr_l2tpip *addr = (struct sockaddr_l2tpip *) uaddr;
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+ int ret = -EINVAL;
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+ int chk_addr_ret;
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+
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+ ret = -EADDRINUSE;
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+ read_lock_bh(&l2tp_ip_lock);
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+ if (__l2tp_ip_bind_lookup(&init_net, addr->l2tp_addr.s_addr, sk->sk_bound_dev_if, addr->l2tp_conn_id))
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+ goto out_in_use;
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+
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+ read_unlock_bh(&l2tp_ip_lock);
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+
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+ lock_sock(sk);
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+ if (sk->sk_state != TCP_CLOSE || addr_len < sizeof(struct sockaddr_l2tpip))
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+ goto out;
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+
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+ chk_addr_ret = inet_addr_type(&init_net, addr->l2tp_addr.s_addr);
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+ ret = -EADDRNOTAVAIL;
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+ if (addr->l2tp_addr.s_addr && chk_addr_ret != RTN_LOCAL &&
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+ chk_addr_ret != RTN_MULTICAST && chk_addr_ret != RTN_BROADCAST)
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+ goto out;
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+
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+ inet->inet_rcv_saddr = inet->inet_saddr = addr->l2tp_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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+ sk_dst_reset(sk);
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+
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+ l2tp_ip_sk(sk)->conn_id = addr->l2tp_conn_id;
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+
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+ write_lock_bh(&l2tp_ip_lock);
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+ sk_add_bind_node(sk, &l2tp_ip_bind_table);
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+ sk_del_node_init(sk);
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+ write_unlock_bh(&l2tp_ip_lock);
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+ ret = 0;
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+out:
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+ release_sock(sk);
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+
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+ return ret;
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+
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+out_in_use:
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+ read_unlock_bh(&l2tp_ip_lock);
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+
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+ return ret;
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+}
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+
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+static int l2tp_ip_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
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+{
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+ int rc;
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+ struct inet_sock *inet = inet_sk(sk);
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+ struct sockaddr_l2tpip *lsa = (struct sockaddr_l2tpip *) uaddr;
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+ struct rtable *rt;
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+ __be32 saddr;
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+ int oif;
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+
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+ rc = -EINVAL;
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+ if (addr_len < sizeof(*lsa))
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+ goto out;
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+
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+ rc = -EAFNOSUPPORT;
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+ if (lsa->l2tp_family != AF_INET)
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+ goto out;
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+
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+ sk_dst_reset(sk);
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+
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+ oif = sk->sk_bound_dev_if;
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+ saddr = inet->inet_saddr;
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+
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+ rc = -EINVAL;
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+ if (ipv4_is_multicast(lsa->l2tp_addr.s_addr))
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+ goto out;
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+
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+ rc = ip_route_connect(&rt, lsa->l2tp_addr.s_addr, saddr,
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+ RT_CONN_FLAGS(sk), oif,
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+ IPPROTO_L2TP,
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+ 0, 0, sk, 1);
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+ if (rc) {
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+ if (rc == -ENETUNREACH)
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+ IP_INC_STATS_BH(&init_net, IPSTATS_MIB_OUTNOROUTES);
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+ goto out;
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+ }
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+
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+ rc = -ENETUNREACH;
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+ if (rt->rt_flags & (RTCF_MULTICAST | RTCF_BROADCAST)) {
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+ ip_rt_put(rt);
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+ goto out;
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+ }
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+
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+ l2tp_ip_sk(sk)->peer_conn_id = lsa->l2tp_conn_id;
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+
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+ if (!inet->inet_saddr)
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+ inet->inet_saddr = rt->rt_src;
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+ if (!inet->inet_rcv_saddr)
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+ inet->inet_rcv_saddr = rt->rt_src;
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+ inet->inet_daddr = rt->rt_dst;
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+ sk->sk_state = TCP_ESTABLISHED;
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+ inet->inet_id = jiffies;
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+
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+ sk_dst_set(sk, &rt->u.dst);
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+
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+ write_lock_bh(&l2tp_ip_lock);
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+ hlist_del_init(&sk->sk_bind_node);
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+ sk_add_bind_node(sk, &l2tp_ip_bind_table);
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+ write_unlock_bh(&l2tp_ip_lock);
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+
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+ rc = 0;
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+out:
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+ return rc;
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+}
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+
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+static int l2tp_ip_getname(struct socket *sock, struct sockaddr *uaddr,
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+ int *uaddr_len, int peer)
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+{
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+ struct sock *sk = sock->sk;
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+ struct inet_sock *inet = inet_sk(sk);
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+ struct l2tp_ip_sock *lsk = l2tp_ip_sk(sk);
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+ struct sockaddr_l2tpip *lsa = (struct sockaddr_l2tpip *)uaddr;
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+
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+ memset(lsa, 0, sizeof(*lsa));
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+ lsa->l2tp_family = AF_INET;
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+ if (peer) {
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+ if (!inet->inet_dport)
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+ return -ENOTCONN;
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+ lsa->l2tp_conn_id = lsk->peer_conn_id;
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+ lsa->l2tp_addr.s_addr = inet->inet_daddr;
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+ } else {
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+ __be32 addr = inet->inet_rcv_saddr;
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+ if (!addr)
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+ addr = inet->inet_saddr;
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+ lsa->l2tp_conn_id = lsk->conn_id;
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+ lsa->l2tp_addr.s_addr = addr;
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+ }
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+ *uaddr_len = sizeof(*lsa);
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+ return 0;
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+}
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+
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+static int l2tp_ip_backlog_recv(struct sock *sk, struct sk_buff *skb)
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+{
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+ int rc;
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+
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+ if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb))
|
|
|
+ goto drop;
|
|
|
+
|
|
|
+ nf_reset(skb);
|
|
|
+
|
|
|
+ /* 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(&init_net, IPSTATS_MIB_INDISCARDS);
|
|
|
+ kfree_skb(skb);
|
|
|
+ return -1;
|
|
|
+}
|
|
|
+
|
|
|
+/* Userspace will call sendmsg() on the tunnel socket to send L2TP
|
|
|
+ * control frames.
|
|
|
+ */
|
|
|
+static int l2tp_ip_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, size_t len)
|
|
|
+{
|
|
|
+ struct sk_buff *skb;
|
|
|
+ int rc;
|
|
|
+ struct l2tp_ip_sock *lsa = l2tp_ip_sk(sk);
|
|
|
+ struct inet_sock *inet = inet_sk(sk);
|
|
|
+ struct ip_options *opt = inet->opt;
|
|
|
+ struct rtable *rt = NULL;
|
|
|
+ int connected = 0;
|
|
|
+ __be32 daddr;
|
|
|
+
|
|
|
+ if (sock_flag(sk, SOCK_DEAD))
|
|
|
+ return -ENOTCONN;
|
|
|
+
|
|
|
+ /* Get and verify the address. */
|
|
|
+ if (msg->msg_name) {
|
|
|
+ struct sockaddr_l2tpip *lip = (struct sockaddr_l2tpip *) msg->msg_name;
|
|
|
+ if (msg->msg_namelen < sizeof(*lip))
|
|
|
+ return -EINVAL;
|
|
|
+
|
|
|
+ if (lip->l2tp_family != AF_INET) {
|
|
|
+ if (lip->l2tp_family != AF_UNSPEC)
|
|
|
+ return -EAFNOSUPPORT;
|
|
|
+ }
|
|
|
+
|
|
|
+ daddr = lip->l2tp_addr.s_addr;
|
|
|
+ } else {
|
|
|
+ if (sk->sk_state != TCP_ESTABLISHED)
|
|
|
+ return -EDESTADDRREQ;
|
|
|
+
|
|
|
+ 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_fromiovec(skb_put(skb, len), msg->msg_iov, len);
|
|
|
+ if (rc < 0) {
|
|
|
+ kfree_skb(skb);
|
|
|
+ goto error;
|
|
|
+ }
|
|
|
+
|
|
|
+ if (connected)
|
|
|
+ rt = (struct rtable *) __sk_dst_check(sk, 0);
|
|
|
+
|
|
|
+ if (rt == NULL) {
|
|
|
+ /* Use correct destination address if we have options. */
|
|
|
+ if (opt && opt->srr)
|
|
|
+ daddr = opt->faddr;
|
|
|
+
|
|
|
+ {
|
|
|
+ struct flowi fl = { .oif = sk->sk_bound_dev_if,
|
|
|
+ .nl_u = { .ip4_u = {
|
|
|
+ .daddr = daddr,
|
|
|
+ .saddr = inet->inet_saddr,
|
|
|
+ .tos = RT_CONN_FLAGS(sk) } },
|
|
|
+ .proto = sk->sk_protocol,
|
|
|
+ .flags = inet_sk_flowi_flags(sk),
|
|
|
+ .uli_u = { .ports = {
|
|
|
+ .sport = inet->inet_sport,
|
|
|
+ .dport = inet->inet_dport } } };
|
|
|
+
|
|
|
+ /* If this fails, retransmit mechanism of transport layer will
|
|
|
+ * keep trying until route appears or the connection times
|
|
|
+ * itself out.
|
|
|
+ */
|
|
|
+ security_sk_classify_flow(sk, &fl);
|
|
|
+ if (ip_route_output_flow(sock_net(sk), &rt, &fl, sk, 0))
|
|
|
+ goto no_route;
|
|
|
+ }
|
|
|
+ sk_setup_caps(sk, &rt->u.dst);
|
|
|
+ }
|
|
|
+ skb_dst_set(skb, dst_clone(&rt->u.dst));
|
|
|
+
|
|
|
+ /* Queue the packet to IP for output */
|
|
|
+ rc = ip_queue_xmit(skb, 0);
|
|
|
+
|
|
|
+error:
|
|
|
+ /* Update stats */
|
|
|
+ if (rc >= 0) {
|
|
|
+ lsa->tx_packets++;
|
|
|
+ lsa->tx_bytes += len;
|
|
|
+ rc = len;
|
|
|
+ } else {
|
|
|
+ lsa->tx_errors++;
|
|
|
+ }
|
|
|
+
|
|
|
+ return rc;
|
|
|
+
|
|
|
+no_route:
|
|
|
+ IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTNOROUTES);
|
|
|
+ kfree_skb(skb);
|
|
|
+ return -EHOSTUNREACH;
|
|
|
+}
|
|
|
+
|
|
|
+static int l2tp_ip_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
|
|
|
+ size_t len, int noblock, int flags, int *addr_len)
|
|
|
+{
|
|
|
+ struct inet_sock *inet = inet_sk(sk);
|
|
|
+ struct l2tp_ip_sock *lsk = l2tp_ip_sk(sk);
|
|
|
+ size_t copied = 0;
|
|
|
+ int err = -EOPNOTSUPP;
|
|
|
+ struct sockaddr_in *sin = (struct sockaddr_in *)msg->msg_name;
|
|
|
+ struct sk_buff *skb;
|
|
|
+
|
|
|
+ if (flags & MSG_OOB)
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ if (addr_len)
|
|
|
+ *addr_len = sizeof(*sin);
|
|
|
+
|
|
|
+ skb = skb_recv_datagram(sk, flags, noblock, &err);
|
|
|
+ if (!skb)
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ copied = skb->len;
|
|
|
+ if (len < copied) {
|
|
|
+ msg->msg_flags |= MSG_TRUNC;
|
|
|
+ copied = len;
|
|
|
+ }
|
|
|
+
|
|
|
+ err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, 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));
|
|
|
+ }
|
|
|
+ if (inet->cmsg_flags)
|
|
|
+ ip_cmsg_recv(msg, skb);
|
|
|
+ if (flags & MSG_TRUNC)
|
|
|
+ copied = skb->len;
|
|
|
+done:
|
|
|
+ skb_free_datagram(sk, skb);
|
|
|
+out:
|
|
|
+ if (err) {
|
|
|
+ lsk->rx_errors++;
|
|
|
+ return err;
|
|
|
+ }
|
|
|
+
|
|
|
+ lsk->rx_packets++;
|
|
|
+ lsk->rx_bytes += copied;
|
|
|
+
|
|
|
+ return copied;
|
|
|
+}
|
|
|
+
|
|
|
+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 = udp_disconnect,
|
|
|
+ .ioctl = udp_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 = inet_hash,
|
|
|
+ .unhash = inet_unhash,
|
|
|
+ .obj_size = sizeof(struct l2tp_ip_sock),
|
|
|
+#ifdef CONFIG_COMPAT
|
|
|
+ .compat_setsockopt = compat_ip_setsockopt,
|
|
|
+ .compat_getsockopt = compat_ip_getsockopt,
|
|
|
+#endif
|
|
|
+};
|
|
|
+
|
|
|
+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,
|
|
|
+ .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,
|
|
|
+#ifdef CONFIG_COMPAT
|
|
|
+ .compat_setsockopt = compat_sock_common_setsockopt,
|
|
|
+ .compat_getsockopt = compat_sock_common_getsockopt,
|
|
|
+#endif
|
|
|
+};
|
|
|
+
|
|
|
+static struct inet_protosw l2tp_ip_protosw = {
|
|
|
+ .type = SOCK_DGRAM,
|
|
|
+ .protocol = IPPROTO_L2TP,
|
|
|
+ .prot = &l2tp_ip_prot,
|
|
|
+ .ops = &l2tp_ip_ops,
|
|
|
+ .no_check = 0,
|
|
|
+};
|
|
|
+
|
|
|
+static struct net_protocol l2tp_ip_protocol __read_mostly = {
|
|
|
+ .handler = l2tp_ip_recv,
|
|
|
+};
|
|
|
+
|
|
|
+static int __init l2tp_ip_init(void)
|
|
|
+{
|
|
|
+ int err;
|
|
|
+
|
|
|
+ printk(KERN_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");
|
|
|
+MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET, SOCK_DGRAM, IPPROTO_L2TP);
|
James Chapman