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![Mathias Krause](/assets/img/avatar_default.png)
The L2TP code for IPv6 fails to initialize the l2tp_conn_id member of struct sockaddr_l2tpip6 and therefore leaks four bytes kernel stack in l2tp_ip6_recvmsg() in case msg_name is set. Initialize l2tp_conn_id with 0 to avoid the info leak. Signed-off-by: Mathias Krause <minipli@googlemail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
811 lines
19 KiB
C
811 lines
19 KiB
C
/*
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* L2TPv3 IP encapsulation support for IPv6
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*
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* Copyright (c) 2012 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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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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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 <linux/in6.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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#include <net/transp_v6.h>
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#include <net/addrconf.h>
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#include <net/ip6_route.h>
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#include "l2tp_core.h"
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struct l2tp_ip6_sock {
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/* inet_sock has to be the first member of l2tp_ip6_sock */
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struct inet_sock inet;
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u32 conn_id;
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u32 peer_conn_id;
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/* ipv6_pinfo has to be the last member of l2tp_ip6_sock, see
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inet6_sk_generic */
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struct ipv6_pinfo inet6;
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};
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static DEFINE_RWLOCK(l2tp_ip6_lock);
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static struct hlist_head l2tp_ip6_table;
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static struct hlist_head l2tp_ip6_bind_table;
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static inline struct l2tp_ip6_sock *l2tp_ip6_sk(const struct sock *sk)
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{
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return (struct l2tp_ip6_sock *)sk;
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}
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static struct sock *__l2tp_ip6_bind_lookup(struct net *net,
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struct in6_addr *laddr,
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int dif, u32 tunnel_id)
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{
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struct sock *sk;
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sk_for_each_bound(sk, &l2tp_ip6_bind_table) {
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struct in6_addr *addr = inet6_rcv_saddr(sk);
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struct l2tp_ip6_sock *l2tp = l2tp_ip6_sk(sk);
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if (l2tp == NULL)
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continue;
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if ((l2tp->conn_id == tunnel_id) &&
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net_eq(sock_net(sk), net) &&
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!(addr && ipv6_addr_equal(addr, 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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sk = NULL;
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found:
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return sk;
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}
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static inline struct sock *l2tp_ip6_bind_lookup(struct net *net,
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struct in6_addr *laddr,
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int dif, u32 tunnel_id)
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{
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struct sock *sk = __l2tp_ip6_bind_lookup(net, laddr, dif, tunnel_id);
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if (sk)
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sock_hold(sk);
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return sk;
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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_ip6_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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/* Point to L2TP header */
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optr = ptr = skb->data;
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if (!pskb_may_pull(skb, 4))
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goto discard;
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session_id = ntohl(*((__be32 *) ptr));
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ptr += 4;
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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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/* 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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tunnel = session->tunnel;
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if (tunnel == NULL)
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goto discard;
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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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pr_debug("%s: ip recv\n", tunnel->name);
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print_hex_dump_bytes("", DUMP_PREFIX_OFFSET, ptr, length);
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}
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l2tp_recv_common(session, skb, ptr, optr, 0, skb->len,
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tunnel->recv_payload_hook);
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return 0;
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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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if ((skb->data[0] & 0xc0) != 0xc0)
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goto discard;
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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 ipv6hdr *iph = ipv6_hdr(skb);
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read_lock_bh(&l2tp_ip6_lock);
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sk = __l2tp_ip6_bind_lookup(&init_net, &iph->daddr,
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0, tunnel_id);
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read_unlock_bh(&l2tp_ip6_lock);
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}
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if (sk == NULL)
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goto discard;
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sock_hold(sk);
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if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
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goto discard_put;
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nf_reset(skb);
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return sk_receive_skb(sk, skb, 1);
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discard_put:
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sock_put(sk);
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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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static int l2tp_ip6_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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write_lock_bh(&l2tp_ip6_lock);
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sk_add_node(sk, &l2tp_ip6_table);
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write_unlock_bh(&l2tp_ip6_lock);
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return 0;
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}
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static void l2tp_ip6_close(struct sock *sk, long timeout)
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{
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write_lock_bh(&l2tp_ip6_lock);
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hlist_del_init(&sk->sk_bind_node);
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sk_del_node_init(sk);
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write_unlock_bh(&l2tp_ip6_lock);
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sk_common_release(sk);
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}
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static void l2tp_ip6_destroy_sock(struct sock *sk)
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{
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struct l2tp_tunnel *tunnel = l2tp_sock_to_tunnel(sk);
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lock_sock(sk);
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ip6_flush_pending_frames(sk);
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release_sock(sk);
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if (tunnel) {
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l2tp_tunnel_closeall(tunnel);
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sock_put(sk);
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}
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inet6_destroy_sock(sk);
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}
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static int l2tp_ip6_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 ipv6_pinfo *np = inet6_sk(sk);
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struct sockaddr_l2tpip6 *addr = (struct sockaddr_l2tpip6 *) uaddr;
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__be32 v4addr = 0;
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int addr_type;
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int err;
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if (!sock_flag(sk, SOCK_ZAPPED))
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return -EINVAL;
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if (addr->l2tp_family != AF_INET6)
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return -EINVAL;
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if (addr_len < sizeof(*addr))
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return -EINVAL;
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addr_type = ipv6_addr_type(&addr->l2tp_addr);
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/* l2tp_ip6 sockets are IPv6 only */
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if (addr_type == IPV6_ADDR_MAPPED)
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return -EADDRNOTAVAIL;
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/* L2TP is point-point, not multicast */
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if (addr_type & IPV6_ADDR_MULTICAST)
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return -EADDRNOTAVAIL;
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err = -EADDRINUSE;
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read_lock_bh(&l2tp_ip6_lock);
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if (__l2tp_ip6_bind_lookup(&init_net, &addr->l2tp_addr,
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sk->sk_bound_dev_if, addr->l2tp_conn_id))
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goto out_in_use;
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read_unlock_bh(&l2tp_ip6_lock);
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lock_sock(sk);
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err = -EINVAL;
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if (sk->sk_state != TCP_CLOSE)
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goto out_unlock;
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/* Check if the address belongs to the host. */
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rcu_read_lock();
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if (addr_type != IPV6_ADDR_ANY) {
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struct net_device *dev = NULL;
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if (addr_type & IPV6_ADDR_LINKLOCAL) {
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if (addr_len >= sizeof(struct sockaddr_in6) &&
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addr->l2tp_scope_id) {
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/* Override any existing binding, if another
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* one is supplied by user.
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*/
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sk->sk_bound_dev_if = addr->l2tp_scope_id;
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}
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/* Binding to link-local address requires an
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interface */
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if (!sk->sk_bound_dev_if)
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goto out_unlock_rcu;
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err = -ENODEV;
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dev = dev_get_by_index_rcu(sock_net(sk),
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sk->sk_bound_dev_if);
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if (!dev)
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goto out_unlock_rcu;
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}
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/* ipv4 addr of the socket is invalid. Only the
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* unspecified and mapped address have a v4 equivalent.
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*/
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v4addr = LOOPBACK4_IPV6;
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err = -EADDRNOTAVAIL;
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if (!ipv6_chk_addr(sock_net(sk), &addr->l2tp_addr, dev, 0))
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goto out_unlock_rcu;
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}
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rcu_read_unlock();
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inet->inet_rcv_saddr = inet->inet_saddr = v4addr;
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np->rcv_saddr = addr->l2tp_addr;
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np->saddr = addr->l2tp_addr;
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l2tp_ip6_sk(sk)->conn_id = addr->l2tp_conn_id;
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write_lock_bh(&l2tp_ip6_lock);
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sk_add_bind_node(sk, &l2tp_ip6_bind_table);
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sk_del_node_init(sk);
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write_unlock_bh(&l2tp_ip6_lock);
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sock_reset_flag(sk, SOCK_ZAPPED);
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release_sock(sk);
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return 0;
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out_unlock_rcu:
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rcu_read_unlock();
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out_unlock:
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release_sock(sk);
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return err;
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out_in_use:
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read_unlock_bh(&l2tp_ip6_lock);
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return err;
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}
|
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|
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static int l2tp_ip6_connect(struct sock *sk, struct sockaddr *uaddr,
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int addr_len)
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{
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struct sockaddr_l2tpip6 *lsa = (struct sockaddr_l2tpip6 *) uaddr;
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struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr;
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struct in6_addr *daddr;
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int addr_type;
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int rc;
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if (sock_flag(sk, SOCK_ZAPPED)) /* Must bind first - autobinding does not work */
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return -EINVAL;
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if (addr_len < sizeof(*lsa))
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return -EINVAL;
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addr_type = ipv6_addr_type(&usin->sin6_addr);
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if (addr_type & IPV6_ADDR_MULTICAST)
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return -EINVAL;
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|
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if (addr_type & IPV6_ADDR_MAPPED) {
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daddr = &usin->sin6_addr;
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if (ipv4_is_multicast(daddr->s6_addr32[3]))
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return -EINVAL;
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}
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|
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rc = ip6_datagram_connect(sk, uaddr, addr_len);
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lock_sock(sk);
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|
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l2tp_ip6_sk(sk)->peer_conn_id = lsa->l2tp_conn_id;
|
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|
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write_lock_bh(&l2tp_ip6_lock);
|
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hlist_del_init(&sk->sk_bind_node);
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sk_add_bind_node(sk, &l2tp_ip6_bind_table);
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write_unlock_bh(&l2tp_ip6_lock);
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|
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release_sock(sk);
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|
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return rc;
|
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}
|
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|
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static int l2tp_ip6_disconnect(struct sock *sk, int flags)
|
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{
|
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if (sock_flag(sk, SOCK_ZAPPED))
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return 0;
|
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|
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return udp_disconnect(sk, flags);
|
|
}
|
|
|
|
static int l2tp_ip6_getname(struct socket *sock, struct sockaddr *uaddr,
|
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int *uaddr_len, int peer)
|
|
{
|
|
struct sockaddr_l2tpip6 *lsa = (struct sockaddr_l2tpip6 *)uaddr;
|
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struct sock *sk = sock->sk;
|
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struct ipv6_pinfo *np = inet6_sk(sk);
|
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struct l2tp_ip6_sock *lsk = l2tp_ip6_sk(sk);
|
|
|
|
lsa->l2tp_family = AF_INET6;
|
|
lsa->l2tp_flowinfo = 0;
|
|
lsa->l2tp_scope_id = 0;
|
|
lsa->l2tp_unused = 0;
|
|
if (peer) {
|
|
if (!lsk->peer_conn_id)
|
|
return -ENOTCONN;
|
|
lsa->l2tp_conn_id = lsk->peer_conn_id;
|
|
lsa->l2tp_addr = np->daddr;
|
|
if (np->sndflow)
|
|
lsa->l2tp_flowinfo = np->flow_label;
|
|
} else {
|
|
if (ipv6_addr_any(&np->rcv_saddr))
|
|
lsa->l2tp_addr = np->saddr;
|
|
else
|
|
lsa->l2tp_addr = np->rcv_saddr;
|
|
|
|
lsa->l2tp_conn_id = lsk->conn_id;
|
|
}
|
|
if (ipv6_addr_type(&lsa->l2tp_addr) & IPV6_ADDR_LINKLOCAL)
|
|
lsa->l2tp_scope_id = sk->sk_bound_dev_if;
|
|
*uaddr_len = sizeof(*lsa);
|
|
return 0;
|
|
}
|
|
|
|
static int l2tp_ip6_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(&init_net, IPSTATS_MIB_INDISCARDS);
|
|
kfree_skb(skb);
|
|
return -1;
|
|
}
|
|
|
|
static int l2tp_ip6_push_pending_frames(struct sock *sk)
|
|
{
|
|
struct sk_buff *skb;
|
|
__be32 *transhdr = NULL;
|
|
int err = 0;
|
|
|
|
skb = skb_peek(&sk->sk_write_queue);
|
|
if (skb == NULL)
|
|
goto out;
|
|
|
|
transhdr = (__be32 *)skb_transport_header(skb);
|
|
*transhdr = 0;
|
|
|
|
err = ip6_push_pending_frames(sk);
|
|
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
/* Userspace will call sendmsg() on the tunnel socket to send L2TP
|
|
* control frames.
|
|
*/
|
|
static int l2tp_ip6_sendmsg(struct kiocb *iocb, struct sock *sk,
|
|
struct msghdr *msg, size_t len)
|
|
{
|
|
struct ipv6_txoptions opt_space;
|
|
struct sockaddr_l2tpip6 *lsa =
|
|
(struct sockaddr_l2tpip6 *) msg->msg_name;
|
|
struct in6_addr *daddr, *final_p, final;
|
|
struct ipv6_pinfo *np = inet6_sk(sk);
|
|
struct ipv6_txoptions *opt = NULL;
|
|
struct ip6_flowlabel *flowlabel = NULL;
|
|
struct dst_entry *dst = NULL;
|
|
struct flowi6 fl6;
|
|
int addr_len = msg->msg_namelen;
|
|
int hlimit = -1;
|
|
int tclass = -1;
|
|
int dontfrag = -1;
|
|
int transhdrlen = 4; /* zero session-id */
|
|
int ulen = len + transhdrlen;
|
|
int err;
|
|
|
|
/* Rough check on arithmetic overflow,
|
|
better check is made in ip6_append_data().
|
|
*/
|
|
if (len > INT_MAX)
|
|
return -EMSGSIZE;
|
|
|
|
/* Mirror BSD error message compatibility */
|
|
if (msg->msg_flags & MSG_OOB)
|
|
return -EOPNOTSUPP;
|
|
|
|
/*
|
|
* Get and verify the address.
|
|
*/
|
|
memset(&fl6, 0, sizeof(fl6));
|
|
|
|
fl6.flowi6_mark = sk->sk_mark;
|
|
|
|
if (lsa) {
|
|
if (addr_len < SIN6_LEN_RFC2133)
|
|
return -EINVAL;
|
|
|
|
if (lsa->l2tp_family && lsa->l2tp_family != AF_INET6)
|
|
return -EAFNOSUPPORT;
|
|
|
|
daddr = &lsa->l2tp_addr;
|
|
if (np->sndflow) {
|
|
fl6.flowlabel = lsa->l2tp_flowinfo & IPV6_FLOWINFO_MASK;
|
|
if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
|
|
flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
|
|
if (flowlabel == NULL)
|
|
return -EINVAL;
|
|
daddr = &flowlabel->dst;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Otherwise it will be difficult to maintain
|
|
* sk->sk_dst_cache.
|
|
*/
|
|
if (sk->sk_state == TCP_ESTABLISHED &&
|
|
ipv6_addr_equal(daddr, &np->daddr))
|
|
daddr = &np->daddr;
|
|
|
|
if (addr_len >= sizeof(struct sockaddr_in6) &&
|
|
lsa->l2tp_scope_id &&
|
|
ipv6_addr_type(daddr) & IPV6_ADDR_LINKLOCAL)
|
|
fl6.flowi6_oif = lsa->l2tp_scope_id;
|
|
} else {
|
|
if (sk->sk_state != TCP_ESTABLISHED)
|
|
return -EDESTADDRREQ;
|
|
|
|
daddr = &np->daddr;
|
|
fl6.flowlabel = np->flow_label;
|
|
}
|
|
|
|
if (fl6.flowi6_oif == 0)
|
|
fl6.flowi6_oif = sk->sk_bound_dev_if;
|
|
|
|
if (msg->msg_controllen) {
|
|
opt = &opt_space;
|
|
memset(opt, 0, sizeof(struct ipv6_txoptions));
|
|
opt->tot_len = sizeof(struct ipv6_txoptions);
|
|
|
|
err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6, opt,
|
|
&hlimit, &tclass, &dontfrag);
|
|
if (err < 0) {
|
|
fl6_sock_release(flowlabel);
|
|
return err;
|
|
}
|
|
if ((fl6.flowlabel & IPV6_FLOWLABEL_MASK) && !flowlabel) {
|
|
flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
|
|
if (flowlabel == NULL)
|
|
return -EINVAL;
|
|
}
|
|
if (!(opt->opt_nflen|opt->opt_flen))
|
|
opt = NULL;
|
|
}
|
|
|
|
if (opt == NULL)
|
|
opt = np->opt;
|
|
if (flowlabel)
|
|
opt = fl6_merge_options(&opt_space, flowlabel, opt);
|
|
opt = ipv6_fixup_options(&opt_space, opt);
|
|
|
|
fl6.flowi6_proto = sk->sk_protocol;
|
|
if (!ipv6_addr_any(daddr))
|
|
fl6.daddr = *daddr;
|
|
else
|
|
fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */
|
|
if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr))
|
|
fl6.saddr = np->saddr;
|
|
|
|
final_p = fl6_update_dst(&fl6, opt, &final);
|
|
|
|
if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
|
|
fl6.flowi6_oif = np->mcast_oif;
|
|
else if (!fl6.flowi6_oif)
|
|
fl6.flowi6_oif = np->ucast_oif;
|
|
|
|
security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
|
|
|
|
dst = ip6_dst_lookup_flow(sk, &fl6, final_p, true);
|
|
if (IS_ERR(dst)) {
|
|
err = PTR_ERR(dst);
|
|
goto out;
|
|
}
|
|
|
|
if (hlimit < 0) {
|
|
if (ipv6_addr_is_multicast(&fl6.daddr))
|
|
hlimit = np->mcast_hops;
|
|
else
|
|
hlimit = np->hop_limit;
|
|
if (hlimit < 0)
|
|
hlimit = ip6_dst_hoplimit(dst);
|
|
}
|
|
|
|
if (tclass < 0)
|
|
tclass = np->tclass;
|
|
|
|
if (dontfrag < 0)
|
|
dontfrag = np->dontfrag;
|
|
|
|
if (msg->msg_flags & MSG_CONFIRM)
|
|
goto do_confirm;
|
|
|
|
back_from_confirm:
|
|
lock_sock(sk);
|
|
err = ip6_append_data(sk, ip_generic_getfrag, msg->msg_iov,
|
|
ulen, transhdrlen, hlimit, tclass, opt,
|
|
&fl6, (struct rt6_info *)dst,
|
|
msg->msg_flags, dontfrag);
|
|
if (err)
|
|
ip6_flush_pending_frames(sk);
|
|
else if (!(msg->msg_flags & MSG_MORE))
|
|
err = l2tp_ip6_push_pending_frames(sk);
|
|
release_sock(sk);
|
|
done:
|
|
dst_release(dst);
|
|
out:
|
|
fl6_sock_release(flowlabel);
|
|
|
|
return err < 0 ? err : len;
|
|
|
|
do_confirm:
|
|
dst_confirm(dst);
|
|
if (!(msg->msg_flags & MSG_PROBE) || len)
|
|
goto back_from_confirm;
|
|
err = 0;
|
|
goto done;
|
|
}
|
|
|
|
static int l2tp_ip6_recvmsg(struct kiocb *iocb, struct sock *sk,
|
|
struct msghdr *msg, size_t len, int noblock,
|
|
int flags, int *addr_len)
|
|
{
|
|
struct ipv6_pinfo *np = inet6_sk(sk);
|
|
struct sockaddr_l2tpip6 *lsa = (struct sockaddr_l2tpip6 *)msg->msg_name;
|
|
size_t copied = 0;
|
|
int err = -EOPNOTSUPP;
|
|
struct sk_buff *skb;
|
|
|
|
if (flags & MSG_OOB)
|
|
goto out;
|
|
|
|
if (addr_len)
|
|
*addr_len = sizeof(*lsa);
|
|
|
|
if (flags & MSG_ERRQUEUE)
|
|
return ipv6_recv_error(sk, msg, len);
|
|
|
|
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 (lsa) {
|
|
lsa->l2tp_family = AF_INET6;
|
|
lsa->l2tp_unused = 0;
|
|
lsa->l2tp_addr = ipv6_hdr(skb)->saddr;
|
|
lsa->l2tp_flowinfo = 0;
|
|
lsa->l2tp_scope_id = 0;
|
|
lsa->l2tp_conn_id = 0;
|
|
if (ipv6_addr_type(&lsa->l2tp_addr) & IPV6_ADDR_LINKLOCAL)
|
|
lsa->l2tp_scope_id = IP6CB(skb)->iif;
|
|
}
|
|
|
|
if (np->rxopt.all)
|
|
ip6_datagram_recv_ctl(sk, msg, skb);
|
|
|
|
if (flags & MSG_TRUNC)
|
|
copied = skb->len;
|
|
done:
|
|
skb_free_datagram(sk, skb);
|
|
out:
|
|
return err ? err : copied;
|
|
}
|
|
|
|
static struct proto l2tp_ip6_prot = {
|
|
.name = "L2TP/IPv6",
|
|
.owner = THIS_MODULE,
|
|
.init = l2tp_ip6_open,
|
|
.close = l2tp_ip6_close,
|
|
.bind = l2tp_ip6_bind,
|
|
.connect = l2tp_ip6_connect,
|
|
.disconnect = l2tp_ip6_disconnect,
|
|
.ioctl = udp_ioctl,
|
|
.destroy = l2tp_ip6_destroy_sock,
|
|
.setsockopt = ipv6_setsockopt,
|
|
.getsockopt = ipv6_getsockopt,
|
|
.sendmsg = l2tp_ip6_sendmsg,
|
|
.recvmsg = l2tp_ip6_recvmsg,
|
|
.backlog_rcv = l2tp_ip6_backlog_recv,
|
|
.hash = inet_hash,
|
|
.unhash = inet_unhash,
|
|
.obj_size = sizeof(struct l2tp_ip6_sock),
|
|
#ifdef CONFIG_COMPAT
|
|
.compat_setsockopt = compat_ipv6_setsockopt,
|
|
.compat_getsockopt = compat_ipv6_getsockopt,
|
|
#endif
|
|
};
|
|
|
|
static const struct proto_ops l2tp_ip6_ops = {
|
|
.family = PF_INET6,
|
|
.owner = THIS_MODULE,
|
|
.release = inet6_release,
|
|
.bind = inet6_bind,
|
|
.connect = inet_dgram_connect,
|
|
.socketpair = sock_no_socketpair,
|
|
.accept = sock_no_accept,
|
|
.getname = l2tp_ip6_getname,
|
|
.poll = datagram_poll,
|
|
.ioctl = inet6_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_ip6_protosw = {
|
|
.type = SOCK_DGRAM,
|
|
.protocol = IPPROTO_L2TP,
|
|
.prot = &l2tp_ip6_prot,
|
|
.ops = &l2tp_ip6_ops,
|
|
.no_check = 0,
|
|
};
|
|
|
|
static struct inet6_protocol l2tp_ip6_protocol __read_mostly = {
|
|
.handler = l2tp_ip6_recv,
|
|
};
|
|
|
|
static int __init l2tp_ip6_init(void)
|
|
{
|
|
int err;
|
|
|
|
pr_info("L2TP IP encapsulation support for IPv6 (L2TPv3)\n");
|
|
|
|
err = proto_register(&l2tp_ip6_prot, 1);
|
|
if (err != 0)
|
|
goto out;
|
|
|
|
err = inet6_add_protocol(&l2tp_ip6_protocol, IPPROTO_L2TP);
|
|
if (err)
|
|
goto out1;
|
|
|
|
inet6_register_protosw(&l2tp_ip6_protosw);
|
|
return 0;
|
|
|
|
out1:
|
|
proto_unregister(&l2tp_ip6_prot);
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
static void __exit l2tp_ip6_exit(void)
|
|
{
|
|
inet6_unregister_protosw(&l2tp_ip6_protosw);
|
|
inet6_del_protocol(&l2tp_ip6_protocol, IPPROTO_L2TP);
|
|
proto_unregister(&l2tp_ip6_prot);
|
|
}
|
|
|
|
module_init(l2tp_ip6_init);
|
|
module_exit(l2tp_ip6_exit);
|
|
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_AUTHOR("Chris Elston <celston@katalix.com>");
|
|
MODULE_DESCRIPTION("L2TP IP encapsulation for IPv6");
|
|
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_INET6, 2, IPPROTO_L2TP);
|