linux/net/l2tp/l2tp_ip6.c
James Chapman aa5e17e1f5 l2tp: store l2tpv3 sessions in per-net IDR
L2TPv3 sessions are currently held in one of two fixed-size hash
lists: either a per-net hashlist (IP-encap), or a per-tunnel hashlist
(UDP-encap), keyed by the L2TPv3 32-bit session_id.

In order to lookup L2TPv3 sessions in UDP-encap tunnels efficiently
without finding the tunnel first via sk_user_data, UDP sessions are
now kept in a per-net session list, keyed by session ID. Convert the
existing per-net hashlist to use an IDR for better performance when
there are many sessions and have L2TPv3 UDP sessions use the same IDR.

Although the L2TPv3 RFC states that the session ID alone identifies
the session, our implementation has allowed the same session ID to be
used in different L2TP UDP tunnels. To retain support for this, a new
per-net session hashtable is used, keyed by the sock and session
ID. If on creating a new session, a session already exists with that
ID in the IDR, the colliding sessions are added to the new hashtable
and the existing IDR entry is flagged. When looking up sessions, the
approach is to first check the IDR and if no unflagged match is found,
check the new hashtable. The sock is made available to session getters
where session ID collisions are to be considered. In this way, the new
hashtable is used only for session ID collisions so can be kept small.

For managing session removal, we need a list of colliding sessions
matching a given ID in order to update or remove the IDR entry of the
ID. This is necessary to detect session ID collisions when future
sessions are created. The list head is allocated on first collision
of a given ID and refcounted.

Signed-off-by: James Chapman <jchapman@katalix.com>
Reviewed-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-06-21 11:33:33 +01:00

811 lines
19 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/* L2TPv3 IP encapsulation support for IPv6
*
* Copyright (c) 2012 Katalix Systems Ltd
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#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 <linux/in6.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 <net/transp_v6.h>
#include <net/addrconf.h>
#include <net/ip6_route.h>
#include "l2tp_core.h"
struct l2tp_ip6_sock {
/* inet_sock has to be the first member of l2tp_ip6_sock */
struct inet_sock inet;
u32 conn_id;
u32 peer_conn_id;
struct ipv6_pinfo inet6;
};
static DEFINE_RWLOCK(l2tp_ip6_lock);
static struct hlist_head l2tp_ip6_table;
static struct hlist_head l2tp_ip6_bind_table;
static inline struct l2tp_ip6_sock *l2tp_ip6_sk(const struct sock *sk)
{
return (struct l2tp_ip6_sock *)sk;
}
static struct sock *__l2tp_ip6_bind_lookup(const struct net *net,
const struct in6_addr *laddr,
const struct in6_addr *raddr,
int dif, u32 tunnel_id)
{
struct sock *sk;
sk_for_each_bound(sk, &l2tp_ip6_bind_table) {
const struct in6_addr *sk_laddr = inet6_rcv_saddr(sk);
const struct in6_addr *sk_raddr = &sk->sk_v6_daddr;
const struct l2tp_ip6_sock *l2tp = l2tp_ip6_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 (sk_laddr && !ipv6_addr_any(sk_laddr) &&
!ipv6_addr_any(laddr) && !ipv6_addr_equal(sk_laddr, laddr))
continue;
if (!ipv6_addr_any(sk_raddr) && raddr &&
!ipv6_addr_any(raddr) && !ipv6_addr_equal(sk_raddr, 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_ip6_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 ipv6hdr *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_v3_session_get(net, NULL, 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 = ipv6_hdr(skb);
read_lock_bh(&l2tp_ip6_lock);
sk = __l2tp_ip6_bind_lookup(net, &iph->daddr, &iph->saddr,
inet6_iif(skb), tunnel_id);
if (!sk) {
read_unlock_bh(&l2tp_ip6_lock);
goto discard;
}
sock_hold(sk);
read_unlock_bh(&l2tp_ip6_lock);
if (!xfrm6_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_ip6_hash(struct sock *sk)
{
if (sk_unhashed(sk)) {
write_lock_bh(&l2tp_ip6_lock);
sk_add_node(sk, &l2tp_ip6_table);
write_unlock_bh(&l2tp_ip6_lock);
}
return 0;
}
static void l2tp_ip6_unhash(struct sock *sk)
{
if (sk_unhashed(sk))
return;
write_lock_bh(&l2tp_ip6_lock);
sk_del_node_init(sk);
write_unlock_bh(&l2tp_ip6_lock);
}
static int l2tp_ip6_open(struct sock *sk)
{
/* Prevent autobind. We don't have ports. */
inet_sk(sk)->inet_num = IPPROTO_L2TP;
l2tp_ip6_hash(sk);
return 0;
}
static void l2tp_ip6_close(struct sock *sk, long timeout)
{
write_lock_bh(&l2tp_ip6_lock);
hlist_del_init(&sk->sk_bind_node);
sk_del_node_init(sk);
write_unlock_bh(&l2tp_ip6_lock);
sk_common_release(sk);
}
static void l2tp_ip6_destroy_sock(struct sock *sk)
{
struct l2tp_tunnel *tunnel = l2tp_sk_to_tunnel(sk);
lock_sock(sk);
ip6_flush_pending_frames(sk);
release_sock(sk);
if (tunnel)
l2tp_tunnel_delete(tunnel);
}
static int l2tp_ip6_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
{
struct inet_sock *inet = inet_sk(sk);
struct ipv6_pinfo *np = inet6_sk(sk);
struct sockaddr_l2tpip6 *addr = (struct sockaddr_l2tpip6 *)uaddr;
struct net *net = sock_net(sk);
__be32 v4addr = 0;
int bound_dev_if;
int addr_type;
int err;
if (addr->l2tp_family != AF_INET6)
return -EINVAL;
if (addr_len < sizeof(*addr))
return -EINVAL;
addr_type = ipv6_addr_type(&addr->l2tp_addr);
/* l2tp_ip6 sockets are IPv6 only */
if (addr_type == IPV6_ADDR_MAPPED)
return -EADDRNOTAVAIL;
/* L2TP is point-point, not multicast */
if (addr_type & IPV6_ADDR_MULTICAST)
return -EADDRNOTAVAIL;
lock_sock(sk);
err = -EINVAL;
if (!sock_flag(sk, SOCK_ZAPPED))
goto out_unlock;
if (sk->sk_state != TCP_CLOSE)
goto out_unlock;
bound_dev_if = sk->sk_bound_dev_if;
/* Check if the address belongs to the host. */
rcu_read_lock();
if (addr_type != IPV6_ADDR_ANY) {
struct net_device *dev = NULL;
if (addr_type & IPV6_ADDR_LINKLOCAL) {
if (addr->l2tp_scope_id)
bound_dev_if = addr->l2tp_scope_id;
/* Binding to link-local address requires an
* interface.
*/
if (!bound_dev_if)
goto out_unlock_rcu;
err = -ENODEV;
dev = dev_get_by_index_rcu(sock_net(sk), bound_dev_if);
if (!dev)
goto out_unlock_rcu;
}
/* ipv4 addr of the socket is invalid. Only the
* unspecified and mapped address have a v4 equivalent.
*/
v4addr = LOOPBACK4_IPV6;
err = -EADDRNOTAVAIL;
if (!ipv6_chk_addr(sock_net(sk), &addr->l2tp_addr, dev, 0))
goto out_unlock_rcu;
}
rcu_read_unlock();
write_lock_bh(&l2tp_ip6_lock);
if (__l2tp_ip6_bind_lookup(net, &addr->l2tp_addr, NULL, bound_dev_if,
addr->l2tp_conn_id)) {
write_unlock_bh(&l2tp_ip6_lock);
err = -EADDRINUSE;
goto out_unlock;
}
inet->inet_saddr = v4addr;
inet->inet_rcv_saddr = v4addr;
sk->sk_bound_dev_if = bound_dev_if;
sk->sk_v6_rcv_saddr = addr->l2tp_addr;
np->saddr = addr->l2tp_addr;
l2tp_ip6_sk(sk)->conn_id = addr->l2tp_conn_id;
sk_add_bind_node(sk, &l2tp_ip6_bind_table);
sk_del_node_init(sk);
write_unlock_bh(&l2tp_ip6_lock);
sock_reset_flag(sk, SOCK_ZAPPED);
release_sock(sk);
return 0;
out_unlock_rcu:
rcu_read_unlock();
out_unlock:
release_sock(sk);
return err;
}
static int l2tp_ip6_connect(struct sock *sk, struct sockaddr *uaddr,
int addr_len)
{
struct sockaddr_l2tpip6 *lsa = (struct sockaddr_l2tpip6 *)uaddr;
struct sockaddr_in6 *usin = (struct sockaddr_in6 *)uaddr;
struct in6_addr *daddr;
int addr_type;
int rc;
if (addr_len < sizeof(*lsa))
return -EINVAL;
if (usin->sin6_family != AF_INET6)
return -EINVAL;
addr_type = ipv6_addr_type(&usin->sin6_addr);
if (addr_type & IPV6_ADDR_MULTICAST)
return -EINVAL;
if (addr_type & IPV6_ADDR_MAPPED) {
daddr = &usin->sin6_addr;
if (ipv4_is_multicast(daddr->s6_addr32[3]))
return -EINVAL;
}
lock_sock(sk);
/* Must bind first - autobinding does not work */
if (sock_flag(sk, SOCK_ZAPPED)) {
rc = -EINVAL;
goto out_sk;
}
rc = __ip6_datagram_connect(sk, uaddr, addr_len);
if (rc < 0)
goto out_sk;
l2tp_ip6_sk(sk)->peer_conn_id = lsa->l2tp_conn_id;
write_lock_bh(&l2tp_ip6_lock);
hlist_del_init(&sk->sk_bind_node);
sk_add_bind_node(sk, &l2tp_ip6_bind_table);
write_unlock_bh(&l2tp_ip6_lock);
out_sk:
release_sock(sk);
return rc;
}
static int l2tp_ip6_disconnect(struct sock *sk, int flags)
{
if (sock_flag(sk, SOCK_ZAPPED))
return 0;
return __udp_disconnect(sk, flags);
}
static int l2tp_ip6_getname(struct socket *sock, struct sockaddr *uaddr,
int peer)
{
struct sockaddr_l2tpip6 *lsa = (struct sockaddr_l2tpip6 *)uaddr;
struct sock *sk = sock->sk;
struct ipv6_pinfo *np = inet6_sk(sk);
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 = sk->sk_v6_daddr;
if (inet6_test_bit(SNDFLOW, sk))
lsa->l2tp_flowinfo = np->flow_label;
} else {
if (ipv6_addr_any(&sk->sk_v6_rcv_saddr))
lsa->l2tp_addr = np->saddr;
else
lsa->l2tp_addr = sk->sk_v6_rcv_saddr;
lsa->l2tp_conn_id = lsk->conn_id;
}
if (ipv6_addr_type(&lsa->l2tp_addr) & IPV6_ADDR_LINKLOCAL)
lsa->l2tp_scope_id = READ_ONCE(sk->sk_bound_dev_if);
return sizeof(*lsa);
}
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(sock_net(sk), 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)
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 sock *sk, struct msghdr *msg, size_t len)
{
struct ipv6_txoptions opt_space;
DECLARE_SOCKADDR(struct sockaddr_l2tpip6 *, lsa, msg->msg_name);
struct in6_addr *daddr, *final_p, final;
struct ipv6_pinfo *np = inet6_sk(sk);
struct ipv6_txoptions *opt_to_free = NULL;
struct ipv6_txoptions *opt = NULL;
struct ip6_flowlabel *flowlabel = NULL;
struct dst_entry *dst = NULL;
struct flowi6 fl6;
struct ipcm6_cookie ipc6;
int addr_len = msg->msg_namelen;
int transhdrlen = 4; /* zero session-id */
int ulen;
int err;
/* Rough check on arithmetic overflow,
* better check is made in ip6_append_data().
*/
if (len > INT_MAX - transhdrlen)
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 = READ_ONCE(sk->sk_mark);
fl6.flowi6_uid = sk->sk_uid;
ipcm6_init(&ipc6);
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 (inet6_test_bit(SNDFLOW, sk)) {
fl6.flowlabel = lsa->l2tp_flowinfo & IPV6_FLOWINFO_MASK;
if (fl6.flowlabel & IPV6_FLOWLABEL_MASK) {
flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
if (IS_ERR(flowlabel))
return -EINVAL;
}
}
/* Otherwise it will be difficult to maintain
* sk->sk_dst_cache.
*/
if (sk->sk_state == TCP_ESTABLISHED &&
ipv6_addr_equal(daddr, &sk->sk_v6_daddr))
daddr = &sk->sk_v6_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 = &sk->sk_v6_daddr;
fl6.flowlabel = np->flow_label;
}
if (fl6.flowi6_oif == 0)
fl6.flowi6_oif = READ_ONCE(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);
ipc6.opt = opt;
err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6, &ipc6);
if (err < 0) {
fl6_sock_release(flowlabel);
return err;
}
if ((fl6.flowlabel & IPV6_FLOWLABEL_MASK) && !flowlabel) {
flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
if (IS_ERR(flowlabel))
return -EINVAL;
}
if (!(opt->opt_nflen | opt->opt_flen))
opt = NULL;
}
if (!opt) {
opt = txopt_get(np);
opt_to_free = opt;
}
if (flowlabel)
opt = fl6_merge_options(&opt_space, flowlabel, opt);
opt = ipv6_fixup_options(&opt_space, opt);
ipc6.opt = 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 = READ_ONCE(np->mcast_oif);
else if (!fl6.flowi6_oif)
fl6.flowi6_oif = READ_ONCE(np->ucast_oif);
security_sk_classify_flow(sk, flowi6_to_flowi_common(&fl6));
if (ipc6.tclass < 0)
ipc6.tclass = np->tclass;
fl6.flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6.flowlabel);
dst = ip6_dst_lookup_flow(sock_net(sk), sk, &fl6, final_p);
if (IS_ERR(dst)) {
err = PTR_ERR(dst);
goto out;
}
if (ipc6.hlimit < 0)
ipc6.hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
if (ipc6.dontfrag < 0)
ipc6.dontfrag = inet6_test_bit(DONTFRAG, sk);
if (msg->msg_flags & MSG_CONFIRM)
goto do_confirm;
back_from_confirm:
lock_sock(sk);
ulen = len + (skb_queue_empty(&sk->sk_write_queue) ? transhdrlen : 0);
err = ip6_append_data(sk, ip_generic_getfrag, msg,
ulen, transhdrlen, &ipc6,
&fl6, dst_rt6_info(dst),
msg->msg_flags);
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);
txopt_put(opt_to_free);
return err < 0 ? err : len;
do_confirm:
if (msg->msg_flags & MSG_PROBE)
dst_confirm_neigh(dst, &fl6.daddr);
if (!(msg->msg_flags & MSG_PROBE) || len)
goto back_from_confirm;
err = 0;
goto done;
}
static int l2tp_ip6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
int flags, int *addr_len)
{
struct ipv6_pinfo *np = inet6_sk(sk);
DECLARE_SOCKADDR(struct sockaddr_l2tpip6 *, lsa, msg->msg_name);
size_t copied = 0;
int err = -EOPNOTSUPP;
struct sk_buff *skb;
if (flags & MSG_OOB)
goto out;
if (flags & MSG_ERRQUEUE)
return ipv6_recv_error(sk, msg, len, addr_len);
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 (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 = inet6_iif(skb);
*addr_len = sizeof(*lsa);
}
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 = l2tp_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 = l2tp_ip6_hash,
.unhash = l2tp_ip6_unhash,
.obj_size = sizeof(struct l2tp_ip6_sock),
.ipv6_pinfo_offset = offsetof(struct l2tp_ip6_sock, inet6),
};
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,
.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,
#ifdef CONFIG_COMPAT
.compat_ioctl = inet6_compat_ioctl,
#endif
};
static struct inet_protosw l2tp_ip6_protosw = {
.type = SOCK_DGRAM,
.protocol = IPPROTO_L2TP,
.prot = &l2tp_ip6_prot,
.ops = &l2tp_ip6_ops,
};
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 values of SOCK_DGRAM (2) as type and IPPROTO_L2TP (115) as protocol,
* because __stringify doesn't like enums
*/
MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET6, 115, 2);
MODULE_ALIAS_NET_PF_PROTO(PF_INET6, 115);