// SPDX-License-Identifier: GPL-2.0-or-later
/*****************************************************************************
* Linux PPP over L2TP (PPPoX/PPPoL2TP) Sockets
*
* PPPoX --- Generic PPP encapsulation socket family
* PPPoL2TP --- PPP over L2TP (RFC 2661)
*
* Version: 2.0.0
*
* Authors: James Chapman ([email protected])
*
* Based on original work by Martijn van Oosterhout <[email protected]>
*
* License:
*/
/* This driver handles only L2TP data frames; control frames are handled by a
* userspace application.
*
* To send data in an L2TP session, userspace opens a PPPoL2TP socket and
* attaches it to a bound UDP socket with local tunnel_id / session_id and
* peer tunnel_id / session_id set. Data can then be sent or received using
* regular socket sendmsg() / recvmsg() calls. Kernel parameters of the socket
* can be read or modified using ioctl() or [gs]etsockopt() calls.
*
* When a PPPoL2TP socket is connected with local and peer session_id values
* zero, the socket is treated as a special tunnel management socket.
*
* Here's example userspace code to create a socket for sending/receiving data
* over an L2TP session:-
*
* struct sockaddr_pppol2tp sax;
* int fd;
* int session_fd;
*
* fd = socket(AF_PPPOX, SOCK_DGRAM, PX_PROTO_OL2TP);
*
* sax.sa_family = AF_PPPOX;
* sax.sa_protocol = PX_PROTO_OL2TP;
* sax.pppol2tp.fd = tunnel_fd; // bound UDP socket
* sax.pppol2tp.addr.sin_addr.s_addr = addr->sin_addr.s_addr;
* sax.pppol2tp.addr.sin_port = addr->sin_port;
* sax.pppol2tp.addr.sin_family = AF_INET;
* sax.pppol2tp.s_tunnel = tunnel_id;
* sax.pppol2tp.s_session = session_id;
* sax.pppol2tp.d_tunnel = peer_tunnel_id;
* sax.pppol2tp.d_session = peer_session_id;
*
* session_fd = connect(fd, (struct sockaddr *)&sax, sizeof(sax));
*
* A pppd plugin that allows PPP traffic to be carried over L2TP using
* this driver is available from the OpenL2TP project at
* http://openl2tp.sourceforge.net.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/string.h>
#include <linux/list.h>
#include <linux/uaccess.h>
#include <linux/kernel.h>
#include <linux/spinlock.h>
#include <linux/kthread.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/errno.h>
#include <linux/jiffies.h>
#include <linux/netdevice.h>
#include <linux/net.h>
#include <linux/inetdevice.h>
#include <linux/skbuff.h>
#include <linux/init.h>
#include <linux/ip.h>
#include <linux/udp.h>
#include <linux/if_pppox.h>
#include <linux/if_pppol2tp.h>
#include <net/sock.h>
#include <linux/ppp_channel.h>
#include <linux/ppp_defs.h>
#include <linux/ppp-ioctl.h>
#include <linux/file.h>
#include <linux/hash.h>
#include <linux/sort.h>
#include <linux/proc_fs.h>
#include <linux/l2tp.h>
#include <linux/nsproxy.h>
#include <net/net_namespace.h>
#include <net/netns/generic.h>
#include <net/ip.h>
#include <net/udp.h>
#include <net/inet_common.h>
#include <asm/byteorder.h>
#include <linux/atomic.h>
#include "l2tp_core.h"
#define PPPOL2TP_DRV_VERSION "V2.0"
/* Space for UDP, L2TP and PPP headers */
#define PPPOL2TP_HEADER_OVERHEAD 40
/* Number of bytes to build transmit L2TP headers.
* Unfortunately the size is different depending on whether sequence numbers
* are enabled.
*/
#define PPPOL2TP_L2TP_HDR_SIZE_SEQ 10
#define PPPOL2TP_L2TP_HDR_SIZE_NOSEQ 6
/* Private data of each session. This data lives at the end of struct
* l2tp_session, referenced via session->priv[].
*/
struct pppol2tp_session {
int owner; /* pid that opened the socket */
struct mutex sk_lock; /* Protects .sk */
struct sock __rcu *sk; /* Pointer to the session PPPoX socket */
struct sock *__sk; /* Copy of .sk, for cleanup */
};
static int pppol2tp_xmit(struct ppp_channel *chan, struct sk_buff *skb);
static const struct ppp_channel_ops pppol2tp_chan_ops = {
.start_xmit = pppol2tp_xmit,
};
static const struct proto_ops pppol2tp_ops;
/* Retrieves the pppol2tp socket associated to a session.
* A reference is held on the returned socket, so this function must be paired
* with sock_put().
*/
static struct sock *pppol2tp_session_get_sock(struct l2tp_session *session)
{
struct pppol2tp_session *ps = l2tp_session_priv(session);
struct sock *sk;
rcu_read_lock();
sk = rcu_dereference(ps->sk);
if (sk)
sock_hold(sk);
rcu_read_unlock();
return sk;
}
/* Helpers to obtain tunnel/session contexts from sockets.
*/
static struct l2tp_session *pppol2tp_sock_to_session(struct sock *sk)
{
struct l2tp_session *session;
if (!sk)
return NULL;
rcu_read_lock();
session = rcu_dereference_sk_user_data(sk);
if (session && refcount_inc_not_zero(&session->ref_count)) {
rcu_read_unlock();
WARN_ON_ONCE(session->magic != L2TP_SESSION_MAGIC);
return session;
}
rcu_read_unlock();
return NULL;
}
/*****************************************************************************
* Receive data handling
*****************************************************************************/
/* Receive message. This is the recvmsg for the PPPoL2TP socket.
*/
static int pppol2tp_recvmsg(struct socket *sock, struct msghdr *msg,
size_t len, int flags)
{
int err;
struct sk_buff *skb;
struct sock *sk = sock->sk;
err = -EIO;
if (sk->sk_state & PPPOX_BOUND)
goto end;
err = 0;
skb = skb_recv_datagram(sk, flags, &err);
if (!skb)
goto end;
if (len > skb->len)
len = skb->len;
else if (len < skb->len)
msg->msg_flags |= MSG_TRUNC;
err = skb_copy_datagram_msg(skb, 0, msg, len);
if (likely(err == 0))
err = len;
kfree_skb(skb);
end:
return err;
}
static void pppol2tp_recv(struct l2tp_session *session, struct sk_buff *skb, int data_len)
{
struct pppol2tp_session *ps = l2tp_session_priv(session);
struct sock *sk = NULL;
/* If the socket is bound, send it in to PPP's input queue. Otherwise
* queue it on the session socket.
*/
rcu_read_lock();
sk = rcu_dereference(ps->sk);
if (!sk)
goto no_sock;
/* If the first two bytes are 0xFF03, consider that it is the PPP's
* Address and Control fields and skip them. The L2TP module has always
* worked this way, although, in theory, the use of these fields should
* be negotiated and handled at the PPP layer. These fields are
* constant: 0xFF is the All-Stations Address and 0x03 the Unnumbered
* Information command with Poll/Final bit set to zero (RFC 1662).
*/
if (pskb_may_pull(skb, 2) && skb->data[0] == PPP_ALLSTATIONS &&
skb->data[1] == PPP_UI)
skb_pull(skb, 2);
if (sk->sk_state & PPPOX_BOUND) {
struct pppox_sock *po;
po = pppox_sk(sk);
ppp_input(&po->chan, skb);
} else {
if (sock_queue_rcv_skb(sk, skb) < 0) {
atomic_long_inc(&session->stats.rx_errors);
kfree_skb(skb);
}
}
rcu_read_unlock();
return;
no_sock:
rcu_read_unlock();
pr_warn_ratelimited("%s: no socket in recv\n", session->name);
kfree_skb(skb);
}
/************************************************************************
* Transmit handling
***********************************************************************/
/* This is the sendmsg for the PPPoL2TP pppol2tp_session socket. We come here
* when a user application does a sendmsg() on the session socket. L2TP and
* PPP headers must be inserted into the user's data.
*/
static int pppol2tp_sendmsg(struct socket *sock, struct msghdr *m,
size_t total_len)
{
struct sock *sk = sock->sk;
struct sk_buff *skb;
int error;
struct l2tp_session *session;
struct l2tp_tunnel *tunnel;
int uhlen;
error = -ENOTCONN;
if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED))
goto error;
/* Get session and tunnel contexts */
error = -EBADF;
session = pppol2tp_sock_to_session(sk);
if (!session)
goto error;
tunnel = session->tunnel;
uhlen = (tunnel->encap == L2TP_ENCAPTYPE_UDP) ? sizeof(struct udphdr) : 0;
/* Allocate a socket buffer */
error = -ENOMEM;
skb = sock_wmalloc(sk, NET_SKB_PAD + sizeof(struct iphdr) +
uhlen + session->hdr_len +
2 + total_len, /* 2 bytes for PPP_ALLSTATIONS & PPP_UI */
0, GFP_KERNEL);
if (!skb)
goto error_put_sess;
/* Reserve space for headers. */
skb_reserve(skb, NET_SKB_PAD);
skb_reset_network_header(skb);
skb_reserve(skb, sizeof(struct iphdr));
skb_reset_transport_header(skb);
skb_reserve(skb, uhlen);
/* Add PPP header */
skb->data[0] = PPP_ALLSTATIONS;
skb->data[1] = PPP_UI;
skb_put(skb, 2);
/* Copy user data into skb */
error = memcpy_from_msg(skb_put(skb, total_len), m, total_len);
if (error < 0) {
kfree_skb(skb);
goto error_put_sess;
}
local_bh_disable();
l2tp_xmit_skb(session, skb);
local_bh_enable();
l2tp_session_put(session);
return total_len;
error_put_sess:
l2tp_session_put(session);
error:
return error;
}
/* Transmit function called by generic PPP driver. Sends PPP frame
* over PPPoL2TP socket.
*
* This is almost the same as pppol2tp_sendmsg(), but rather than
* being called with a msghdr from userspace, it is called with a skb
* from the kernel.
*
* The supplied skb from ppp doesn't have enough headroom for the
* insertion of L2TP, UDP and IP headers so we need to allocate more
* headroom in the skb. This will create a cloned skb. But we must be
* careful in the error case because the caller will expect to free
* the skb it supplied, not our cloned skb. So we take care to always
* leave the original skb unfreed if we return an error.
*/
static int pppol2tp_xmit(struct ppp_channel *chan, struct sk_buff *skb)
{
struct sock *sk = (struct sock *)chan->private;
struct l2tp_session *session;
struct l2tp_tunnel *tunnel;
int uhlen, headroom;
if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED))
goto abort;
/* Get session and tunnel contexts from the socket */
session = pppol2tp_sock_to_session(sk);
if (!session)
goto abort;
tunnel = session->tunnel;
uhlen = (tunnel->encap == L2TP_ENCAPTYPE_UDP) ? sizeof(struct udphdr) : 0;
headroom = NET_SKB_PAD +
sizeof(struct iphdr) + /* IP header */
uhlen + /* UDP header (if L2TP_ENCAPTYPE_UDP) */
session->hdr_len + /* L2TP header */
2; /* 2 bytes for PPP_ALLSTATIONS & PPP_UI */
if (skb_cow_head(skb, headroom))
goto abort_put_sess;
/* Setup PPP header */
__skb_push(skb, 2);
skb->data[0] = PPP_ALLSTATIONS;
skb->data[1] = PPP_UI;
local_bh_disable();
l2tp_xmit_skb(session, skb);
local_bh_enable();
l2tp_session_put(session);
return 1;
abort_put_sess:
l2tp_session_put(session);
abort:
/* Free the original skb */
kfree_skb(skb);
return 1;
}
/*****************************************************************************
* Session (and tunnel control) socket create/destroy.
*****************************************************************************/
/* Really kill the session socket. (Called from sock_put() if
* refcnt == 0.)
*/
static void pppol2tp_session_destruct(struct sock *sk)
{
skb_queue_purge(&sk->sk_receive_queue);
skb_queue_purge(&sk->sk_write_queue);
}
static void pppol2tp_session_close(struct l2tp_session *session)
{
struct pppol2tp_session *ps;
ps = l2tp_session_priv(session);
mutex_lock(&ps->sk_lock);
ps->__sk = rcu_dereference_protected(ps->sk,
lockdep_is_held(&ps->sk_lock));
RCU_INIT_POINTER(ps->sk, NULL);
mutex_unlock(&ps->sk_lock);
if (ps->__sk) {
/* detach socket */
rcu_assign_sk_user_data(ps->__sk, NULL);
sock_put(ps->__sk);
/* drop ref taken when we referenced socket via sk_user_data */
l2tp_session_put(session);
}
}
/* Called when the PPPoX socket (session) is closed.
*/
static int pppol2tp_release(struct socket *sock)
{
struct sock *sk = sock->sk;
struct l2tp_session *session;
int error;
if (!sk)
return 0;
error = -EBADF;
lock_sock(sk);
if (sock_flag(sk, SOCK_DEAD) != 0)
goto error;
pppox_unbind_sock(sk);
/* Signal the death of the socket. */
sk->sk_state = PPPOX_DEAD;
sock_orphan(sk);
sock->sk = NULL;
session = pppol2tp_sock_to_session(sk);
if (session) {
l2tp_session_delete(session);
/* drop ref taken by pppol2tp_sock_to_session */
l2tp_session_put(session);
}
release_sock(sk);
sock_put(sk);
return 0;
error:
release_sock(sk);
return error;
}
static struct proto pppol2tp_sk_proto = {
.name = "PPPOL2TP",
.owner = THIS_MODULE,
.obj_size = sizeof(struct pppox_sock),
};
static int pppol2tp_backlog_recv(struct sock *sk, struct sk_buff *skb)
{
int rc;
rc = l2tp_udp_encap_recv(sk, skb);
if (rc)
kfree_skb(skb);
return NET_RX_SUCCESS;
}
/* socket() handler. Initialize a new struct sock.
*/
static int pppol2tp_create(struct net *net, struct socket *sock, int kern)
{
int error = -ENOMEM;
struct sock *sk;
sk = sk_alloc(net, PF_PPPOX, GFP_KERNEL, &pppol2tp_sk_proto, kern);
if (!sk)
goto out;
sock_init_data(sock, sk);
sock_set_flag(sk, SOCK_RCU_FREE);
sock->state = SS_UNCONNECTED;
sock->ops = &pppol2tp_ops;
sk->sk_backlog_rcv = pppol2tp_backlog_recv;
sk->sk_protocol = PX_PROTO_OL2TP;
sk->sk_family = PF_PPPOX;
sk->sk_state = PPPOX_NONE;
sk->sk_type = SOCK_STREAM;
sk->sk_destruct = pppol2tp_session_destruct;
error = 0;
out:
return error;
}
static void pppol2tp_show(struct seq_file *m, void *arg)
{
struct l2tp_session *session = arg;
struct sock *sk;
sk = pppol2tp_session_get_sock(session);
if (sk) {
struct pppox_sock *po = pppox_sk(sk);
seq_printf(m, " interface %s\n", ppp_dev_name(&po->chan));
sock_put(sk);
}
}
static void pppol2tp_session_init(struct l2tp_session *session)
{
struct pppol2tp_session *ps;
session->recv_skb = pppol2tp_recv;
session->session_close = pppol2tp_session_close;
if (IS_ENABLED(CONFIG_L2TP_DEBUGFS))
session->show = pppol2tp_show;
ps = l2tp_session_priv(session);
mutex_init(&ps->sk_lock);
ps->owner = current->pid;
}
struct l2tp_connect_info {
u8 version;
int fd;
u32 tunnel_id;
u32 peer_tunnel_id;
u32 session_id;
u32 peer_session_id;
};
static int pppol2tp_sockaddr_get_info(const void *sa, int sa_len,
struct l2tp_connect_info *info)
{
switch (sa_len) {
case sizeof(struct sockaddr_pppol2tp):
{
const struct sockaddr_pppol2tp *sa_v2in4 = sa;
if (sa_v2in4->sa_protocol != PX_PROTO_OL2TP)
return -EINVAL;
info->version = 2;
info->fd = sa_v2in4->pppol2tp.fd;
info->tunnel_id = sa_v2in4->pppol2tp.s_tunnel;
info->peer_tunnel_id = sa_v2in4->pppol2tp.d_tunnel;
info->session_id = sa_v2in4->pppol2tp.s_session;
info->peer_session_id = sa_v2in4->pppol2tp.d_session;
break;
}
case sizeof(struct sockaddr_pppol2tpv3):
{
const struct sockaddr_pppol2tpv3 *sa_v3in4 = sa;
if (sa_v3in4->sa_protocol != PX_PROTO_OL2TP)
return -EINVAL;
info->version = 3;
info->fd = sa_v3in4->pppol2tp.fd;
info->tunnel_id = sa_v3in4->pppol2tp.s_tunnel;
info->peer_tunnel_id = sa_v3in4->pppol2tp.d_tunnel;
info->session_id = sa_v3in4->pppol2tp.s_session;
info->peer_session_id = sa_v3in4->pppol2tp.d_session;
break;
}
case sizeof(struct sockaddr_pppol2tpin6):
{
const struct sockaddr_pppol2tpin6 *sa_v2in6 = sa;
if (sa_v2in6->sa_protocol != PX_PROTO_OL2TP)
return -EINVAL;
info->version = 2;
info->fd = sa_v2in6->pppol2tp.fd;
info->tunnel_id = sa_v2in6->pppol2tp.s_tunnel;
info->peer_tunnel_id = sa_v2in6->pppol2tp.d_tunnel;
info->session_id = sa_v2in6->pppol2tp.s_session;
info->peer_session_id = sa_v2in6->pppol2tp.d_session;
break;
}
case sizeof(struct sockaddr_pppol2tpv3in6):
{
const struct sockaddr_pppol2tpv3in6 *sa_v3in6 = sa;
if (sa_v3in6->sa_protocol != PX_PROTO_OL2TP)
return -EINVAL;
info->version = 3;
info->fd = sa_v3in6->pppol2tp.fd;
info->tunnel_id = sa_v3in6->pppol2tp.s_tunnel;
info->peer_tunnel_id = sa_v3in6->pppol2tp.d_tunnel;
info->session_id = sa_v3in6->pppol2tp.s_session;
info->peer_session_id = sa_v3in6->pppol2tp.d_session;
break;
}
default:
return -EINVAL;
}
return 0;
}
/* Rough estimation of the maximum payload size a tunnel can transmit without
* fragmenting at the lower IP layer. Assumes L2TPv2 with sequence
* numbers and no IP option. Not quite accurate, but the result is mostly
* unused anyway.
*/
static int pppol2tp_tunnel_mtu(const struct l2tp_tunnel *tunnel)
{
int mtu;
mtu = l2tp_tunnel_dst_mtu(tunnel);
if (mtu <= PPPOL2TP_HEADER_OVERHEAD)
return 1500 - PPPOL2TP_HEADER_OVERHEAD;
return mtu - PPPOL2TP_HEADER_OVERHEAD;
}
static struct l2tp_tunnel *pppol2tp_tunnel_get(struct net *net,
const struct l2tp_connect_info *info,
bool *new_tunnel)
{
struct l2tp_tunnel *tunnel;
int error;
*new_tunnel = false;
tunnel = l2tp_tunnel_get(net, info->tunnel_id);
/* Special case: create tunnel context if session_id and
* peer_session_id is 0. Otherwise look up tunnel using supplied
* tunnel id.
*/
if (!info->session_id && !info->peer_session_id) {
if (!tunnel) {
struct l2tp_tunnel_cfg tcfg = {
.encap = L2TP_ENCAPTYPE_UDP,
};
/* Prevent l2tp_tunnel_register() from trying to set up
* a kernel socket.
*/
if (info->fd < 0)
return ERR_PTR(-EBADF);
error = l2tp_tunnel_create(info->fd,
info->version,
info->tunnel_id,
info->peer_tunnel_id, &tcfg,
&tunnel);
if (error < 0)
return ERR_PTR(error);
refcount_inc(&tunnel->ref_count);
error = l2tp_tunnel_register(tunnel, net, &tcfg);
if (error < 0) {
kfree(tunnel);
return ERR_PTR(error);
}
*new_tunnel = true;
}
} else {
/* Error if we can't find the tunnel */
if (!tunnel)
return ERR_PTR(-ENOENT);
/* Error if socket is not prepped */
if (!tunnel->sock) {
l2tp_tunnel_put(tunnel);
return ERR_PTR(-ENOENT);
}
}
return tunnel;
}
/* connect() handler. Attach a PPPoX socket to a tunnel UDP socket
*/
static int pppol2tp_connect(struct socket *sock, struct sockaddr *uservaddr,
int sockaddr_len, int flags)
{
struct sock *sk = sock->sk;
struct pppox_sock *po = pppox_sk(sk);
struct l2tp_session *session = NULL;
struct l2tp_connect_info info;
struct l2tp_tunnel *tunnel;
struct pppol2tp_session *ps;
struct l2tp_session_cfg cfg = { 0, };
bool drop_refcnt = false;
bool new_session = false;
bool new_tunnel = false;
int error;
error = pppol2tp_sockaddr_get_info(uservaddr, sockaddr_len, &info);
if (error < 0)
return error;
/* Don't bind if tunnel_id is 0 */
if (!info.tunnel_id)
return -EINVAL;
tunnel = pppol2tp_tunnel_get(sock_net(sk), &info, &new_tunnel);
if (IS_ERR(tunnel))
return PTR_ERR(tunnel);
lock_sock(sk);
/* Check for already bound sockets */
error = -EBUSY;
if (sk->sk_state & PPPOX_CONNECTED)
goto end;
/* We don't supporting rebinding anyway */
error = -EALREADY;
if (sk->sk_user_data)
goto end; /* socket is already attached */
if (tunnel->peer_tunnel_id == 0)
tunnel->peer_tunnel_id = info.peer_tunnel_id;
session = l2tp_session_get(sock_net(sk), tunnel->sock, tunnel->version,
info.tunnel_id, info.session_id);
if (session) {
drop_refcnt = true;
if (session->pwtype != L2TP_PWTYPE_PPP) {
error = -EPROTOTYPE;
goto end;
}
ps = l2tp_session_priv(session);
/* Using a pre-existing session is fine as long as it hasn't
* been connected yet.
*/
mutex_lock(&ps->sk_lock);
if (rcu_dereference_protected(ps->sk,
lockdep_is_held(&ps->sk_lock)) ||
ps->__sk) {
mutex_unlock(&ps->sk_lock);
error = -EEXIST;
goto end;
}
} else {
cfg.pw_type = L2TP_PWTYPE_PPP;
session = l2tp_session_create(sizeof(struct pppol2tp_session),
tunnel, info.session_id,
info.peer_session_id, &cfg);
if (IS_ERR(session)) {
error = PTR_ERR(session);
goto end;
}
drop_refcnt = true;
pppol2tp_session_init(session);
ps = l2tp_session_priv(session);
refcount_inc(&session->ref_count);
mutex_lock(&ps->sk_lock);
error = l2tp_session_register(session, tunnel);
if (error < 0) {
mutex_unlock(&ps->sk_lock);
l2tp_session_put(session);
goto end;
}
new_session = true;
}
/* Special case: if source & dest session_id == 0x0000, this
* socket is being created to manage the tunnel. Just set up
* the internal context for use by ioctl() and sockopt()
* handlers.
*/
if (session->session_id == 0 && session->peer_session_id == 0) {
error = 0;
goto out_no_ppp;
}
/* The only header we need to worry about is the L2TP
* header. This size is different depending on whether
* sequence numbers are enabled for the data channel.
*/
po->chan.hdrlen = PPPOL2TP_L2TP_HDR_SIZE_NOSEQ;
po->chan.private = sk;
po->chan.ops = &pppol2tp_chan_ops;
po->chan.mtu = pppol2tp_tunnel_mtu(tunnel);
error = ppp_register_net_channel(sock_net(sk), &po->chan);
if (error) {
mutex_unlock(&ps->sk_lock);
goto end;
}
out_no_ppp:
/* This is how we get the session context from the socket. */
sock_hold(sk);
rcu_assign_sk_user_data(sk, session);
rcu_assign_pointer(ps->sk, sk);
mutex_unlock(&ps->sk_lock);
/* Keep the reference we've grabbed on the session: sk doesn't expect
* the session to disappear. pppol2tp_session_close() is responsible
* for dropping it.
*/
drop_refcnt = false;
sk->sk_state = PPPOX_CONNECTED;
end:
if (error) {
if (new_session)
l2tp_session_delete(session);
if (new_tunnel)
l2tp_tunnel_delete(tunnel);
}
if (drop_refcnt)
l2tp_session_put(session);
l2tp_tunnel_put(tunnel);
release_sock(sk);
return error;
}
#ifdef CONFIG_L2TP_V3
/* Called when creating sessions via the netlink interface. */
static int pppol2tp_session_create(struct net *net, struct l2tp_tunnel *tunnel,
u32 session_id, u32 peer_session_id,
struct l2tp_session_cfg *cfg)
{
int error;
struct l2tp_session *session;
/* Error if tunnel socket is not prepped */
if (!tunnel->sock) {
error = -ENOENT;
goto err;
}
/* Allocate and initialize a new session context. */
session = l2tp_session_create(sizeof(struct pppol2tp_session),
tunnel, session_id,
peer_session_id, cfg);
if (IS_ERR(session)) {
error = PTR_ERR(session);
goto err;
}
pppol2tp_session_init(session);
error = l2tp_session_register(session, tunnel);
if (error < 0)
goto err_sess;
return 0;
err_sess:
l2tp_session_put(session);
err:
return error;
}
#endif /* CONFIG_L2TP_V3 */
/* getname() support.
*/
static int pppol2tp_getname(struct socket *sock, struct sockaddr *uaddr,
int peer)
{
int len = 0;
int error = 0;
struct l2tp_session *session;
struct l2tp_tunnel *tunnel;
struct sock *sk = sock->sk;
struct inet_sock *inet;
struct pppol2tp_session *pls;
error = -ENOTCONN;
if (!sk)
goto end;
if (!(sk->sk_state & PPPOX_CONNECTED))
goto end;
error = -EBADF;
session = pppol2tp_sock_to_session(sk);
if (!session)
goto end;
pls = l2tp_session_priv(session);
tunnel = session->tunnel;
inet = inet_sk(tunnel->sock);
if (tunnel->version == 2 && tunnel->sock->sk_family == AF_INET) {
struct sockaddr_pppol2tp sp;
len = sizeof(sp);
memset(&sp, 0, len);
sp.sa_family = AF_PPPOX;
sp.sa_protocol = PX_PROTO_OL2TP;
sp.pppol2tp.fd = tunnel->fd;
sp.pppol2tp.pid = pls->owner;
sp.pppol2tp.s_tunnel = tunnel->tunnel_id;
sp.pppol2tp.d_tunnel = tunnel->peer_tunnel_id;
sp.pppol2tp.s_session = session->session_id;
sp.pppol2tp.d_session = session->peer_session_id;
sp.pppol2tp.addr.sin_family = AF_INET;
sp.pppol2tp.addr.sin_port = inet->inet_dport;
sp.pppol2tp.addr.sin_addr.s_addr = inet->inet_daddr;
memcpy(uaddr, &sp, len);
#if IS_ENABLED(CONFIG_IPV6)
} else if (tunnel->version == 2 && tunnel->sock->sk_family == AF_INET6) {
struct sockaddr_pppol2tpin6 sp;
len = sizeof(sp);
memset(&sp, 0, len);
sp.sa_family = AF_PPPOX;
sp.sa_protocol = PX_PROTO_OL2TP;
sp.pppol2tp.fd = tunnel->fd;
sp.pppol2tp.pid = pls->owner;
sp.pppol2tp.s_tunnel = tunnel->tunnel_id;
sp.pppol2tp.d_tunnel = tunnel->peer_tunnel_id;
sp.pppol2tp.s_session = session->session_id;
sp.pppol2tp.d_session = session->peer_session_id;
sp.pppol2tp.addr.sin6_family = AF_INET6;
sp.pppol2tp.addr.sin6_port = inet->inet_dport;
memcpy(&sp.pppol2tp.addr.sin6_addr, &tunnel->sock->sk_v6_daddr,
sizeof(tunnel->sock->sk_v6_daddr));
memcpy(uaddr, &sp, len);
} else if (tunnel->version == 3 && tunnel->sock->sk_family == AF_INET6) {
struct sockaddr_pppol2tpv3in6 sp;
len = sizeof(sp);
memset(&sp, 0, len);
sp.sa_family = AF_PPPOX;
sp.sa_protocol = PX_PROTO_OL2TP;
sp.pppol2tp.fd = tunnel->fd;
sp.pppol2tp.pid = pls->owner;
sp.pppol2tp.s_tunnel = tunnel->tunnel_id;
sp.pppol2tp.d_tunnel = tunnel->peer_tunnel_id;
sp.pppol2tp.s_session = session->session_id;
sp.pppol2tp.d_session = session->peer_session_id;
sp.pppol2tp.addr.sin6_family = AF_INET6;
sp.pppol2tp.addr.sin6_port = inet->inet_dport;
memcpy(&sp.pppol2tp.addr.sin6_addr, &tunnel->sock->sk_v6_daddr,
sizeof(tunnel->sock->sk_v6_daddr));
memcpy(uaddr, &sp, len);
#endif
} else if (tunnel->version == 3) {
struct sockaddr_pppol2tpv3 sp;
len = sizeof(sp);
memset(&sp, 0, len);
sp.sa_family = AF_PPPOX;
sp.sa_protocol = PX_PROTO_OL2TP;
sp.pppol2tp.fd = tunnel->fd;
sp.pppol2tp.pid = pls->owner;
sp.pppol2tp.s_tunnel = tunnel->tunnel_id;
sp.pppol2tp.d_tunnel = tunnel->peer_tunnel_id;
sp.pppol2tp.s_session = session->session_id;
sp.pppol2tp.d_session = session->peer_session_id;
sp.pppol2tp.addr.sin_family = AF_INET;
sp.pppol2tp.addr.sin_port = inet->inet_dport;
sp.pppol2tp.addr.sin_addr.s_addr = inet->inet_daddr;
memcpy(uaddr, &sp, len);
}
error = len;
l2tp_session_put(session);
end:
return error;
}
/****************************************************************************
* ioctl() handlers.
*
* The PPPoX socket is created for L2TP sessions: tunnels have their own UDP
* sockets. However, in order to control kernel tunnel features, we allow
* userspace to create a special "tunnel" PPPoX socket which is used for
* control only. Tunnel PPPoX sockets have session_id == 0 and simply allow
* the user application to issue L2TP setsockopt(), getsockopt() and ioctl()
* calls.
****************************************************************************/
static void pppol2tp_copy_stats(struct pppol2tp_ioc_stats *dest,
const struct l2tp_stats *stats)
{
memset(dest, 0, sizeof(*dest));
dest->tx_packets = atomic_long_read(&stats->tx_packets);
dest->tx_bytes = atomic_long_read(&stats->tx_bytes);
dest->tx_errors = atomic_long_read(&stats->tx_errors);
dest->rx_packets = atomic_long_read(&stats->rx_packets);
dest->rx_bytes = atomic_long_read(&stats->rx_bytes);
dest->rx_seq_discards = atomic_long_read(&stats->rx_seq_discards);
dest->rx_oos_packets = atomic_long_read(&stats->rx_oos_packets);
dest->rx_errors = atomic_long_read(&stats->rx_errors);
}
static int pppol2tp_tunnel_copy_stats(struct pppol2tp_ioc_stats *stats,
struct l2tp_tunnel *tunnel)
{
struct l2tp_session *session;
if (!stats->session_id) {
pppol2tp_copy_stats(stats, &tunnel->stats);
return 0;
}
/* If session_id is set, search the corresponding session in the
* context of this tunnel and record the session's statistics.
*/
session = l2tp_session_get(tunnel->l2tp_net, tunnel->sock, tunnel->version,
tunnel->tunnel_id, stats->session_id);
if (!session)
return -EBADR;
if (session->pwtype != L2TP_PWTYPE_PPP) {
l2tp_session_put(session);
return -EBADR;
}
pppol2tp_copy_stats(stats, &session->stats);
l2tp_session_put(session);
return 0;
}
static int pppol2tp_ioctl(struct socket *sock, unsigned int cmd,
unsigned long arg)
{
struct pppol2tp_ioc_stats stats;
struct l2tp_session *session;
switch (cmd) {
case PPPIOCGMRU:
case PPPIOCGFLAGS:
session = sock->sk->sk_user_data;
if (!session)
return -ENOTCONN;
if (WARN_ON(session->magic != L2TP_SESSION_MAGIC))
return -EBADF;
/* Not defined for tunnels */
if (!session->session_id && !session->peer_session_id)
return -ENOSYS;
if (put_user(0, (int __user *)arg))
return -EFAULT;
break;
case PPPIOCSMRU:
case PPPIOCSFLAGS:
session = sock->sk->sk_user_data;
if (!session)
return -ENOTCONN;
if (WARN_ON(session->magic != L2TP_SESSION_MAGIC))
return -EBADF;
/* Not defined for tunnels */
if (!session->session_id && !session->peer_session_id)
return -ENOSYS;
if (!access_ok((int __user *)arg, sizeof(int)))
return -EFAULT;
break;
case PPPIOCGL2TPSTATS:
session = sock->sk->sk_user_data;
if (!session)
return -ENOTCONN;
if (WARN_ON(session->magic != L2TP_SESSION_MAGIC))
return -EBADF;
/* Session 0 represents the parent tunnel */
if (!session->session_id && !session->peer_session_id) {
u32 session_id;
int err;
if (copy_from_user(&stats, (void __user *)arg,
sizeof(stats)))
return -EFAULT;
session_id = stats.session_id;
err = pppol2tp_tunnel_copy_stats(&stats,
session->tunnel);
if (err < 0)
return err;
stats.session_id = session_id;
} else {
pppol2tp_copy_stats(&stats, &session->stats);
stats.session_id = session->session_id;
}
stats.tunnel_id = session->tunnel->tunnel_id;
stats.using_ipsec = l2tp_tunnel_uses_xfrm(session->tunnel);
if (copy_to_user((void __user *)arg, &stats, sizeof(stats)))
return -EFAULT;
break;
default:
return -ENOIOCTLCMD;
}
return 0;
}
/*****************************************************************************
* setsockopt() / getsockopt() support.
*
* The PPPoX socket is created for L2TP sessions: tunnels have their own UDP
* sockets. In order to control kernel tunnel features, we allow userspace to
* create a special "tunnel" PPPoX socket which is used for control only.
* Tunnel PPPoX sockets have session_id == 0 and simply allow the user
* application to issue L2TP setsockopt(), getsockopt() and ioctl() calls.
*****************************************************************************/
/* Tunnel setsockopt() helper.
*/
static int pppol2tp_tunnel_setsockopt(struct sock *sk,
struct l2tp_tunnel *tunnel,
int optname, int val)
{
int err = 0;
switch (optname) {
case PPPOL2TP_SO_DEBUG:
/* Tunnel debug flags option is deprecated */
break;
default:
err = -ENOPROTOOPT;
break;
}
return err;
}
/* Session setsockopt helper.
*/
static int pppol2tp_session_setsockopt(struct sock *sk,
struct l2tp_session *session,
int optname, int val)
{
int err = 0;
switch (optname) {
case PPPOL2TP_SO_RECVSEQ:
if (val != 0 && val != 1) {
err = -EINVAL;
break;
}
session->recv_seq = !!val;
break;
case PPPOL2TP_SO_SENDSEQ:
if (val != 0 && val != 1) {
err = -EINVAL;
break;
}
session->send_seq = !!val;
{
struct pppox_sock *po = pppox_sk(sk);
po->chan.hdrlen = val ? PPPOL2TP_L2TP_HDR_SIZE_SEQ :
PPPOL2TP_L2TP_HDR_SIZE_NOSEQ;
}
l2tp_session_set_header_len(session, session->tunnel->version,
session->tunnel->encap);
break;
case PPPOL2TP_SO_LNSMODE:
if (val != 0 && val != 1) {
err = -EINVAL;
break;
}
session->lns_mode = !!val;
break;
case PPPOL2TP_SO_DEBUG:
/* Session debug flags option is deprecated */
break;
case PPPOL2TP_SO_REORDERTO:
session->reorder_timeout = msecs_to_jiffies(val);
break;
default:
err = -ENOPROTOOPT;
break;
}
return err;
}
/* Main setsockopt() entry point.
* Does API checks, then calls either the tunnel or session setsockopt
* handler, according to whether the PPPoL2TP socket is a for a regular
* session or the special tunnel type.
*/
static int pppol2tp_setsockopt(struct socket *sock, int level, int optname,
sockptr_t optval, unsigned int optlen)
{
struct sock *sk = sock->sk;
struct l2tp_session *session;
struct l2tp_tunnel *tunnel;
int val;
int err;
if (level != SOL_PPPOL2TP)
return -EINVAL;
if (optlen < sizeof(int))
return -EINVAL;
if (copy_from_sockptr(&val, optval, sizeof(int)))
return -EFAULT;
err = -ENOTCONN;
if (!sk->sk_user_data)
goto end;
/* Get session context from the socket */
err = -EBADF;
session = pppol2tp_sock_to_session(sk);
if (!session)
goto end;
/* Special case: if session_id == 0x0000, treat as operation on tunnel
*/
if (session->session_id == 0 && session->peer_session_id == 0) {
tunnel = session->tunnel;
err = pppol2tp_tunnel_setsockopt(sk, tunnel, optname, val);
} else {
err = pppol2tp_session_setsockopt(sk, session, optname, val);
}
l2tp_session_put(session);
end:
return err;
}
/* Tunnel getsockopt helper. Called with sock locked.
*/
static int pppol2tp_tunnel_getsockopt(struct sock *sk,
struct l2tp_tunnel *tunnel,
int optname, int *val)
{
int err = 0;
switch (optname) {
case PPPOL2TP_SO_DEBUG:
/* Tunnel debug flags option is deprecated */
*val = 0;
break;
default:
err = -ENOPROTOOPT;
break;
}
return err;
}
/* Session getsockopt helper. Called with sock locked.
*/
static int pppol2tp_session_getsockopt(struct sock *sk,
struct l2tp_session *session,
int optname, int *val)
{
int err = 0;
switch (optname) {
case PPPOL2TP_SO_RECVSEQ:
*val = session->recv_seq;
break;
case PPPOL2TP_SO_SENDSEQ:
*val = session->send_seq;
break;
case PPPOL2TP_SO_LNSMODE:
*val = session->lns_mode;
break;
case PPPOL2TP_SO_DEBUG:
/* Session debug flags option is deprecated */
*val = 0;
break;
case PPPOL2TP_SO_REORDERTO:
*val = (int)jiffies_to_msecs(session->reorder_timeout);
break;
default:
err = -ENOPROTOOPT;
}
return err;
}
/* Main getsockopt() entry point.
* Does API checks, then calls either the tunnel or session getsockopt
* handler, according to whether the PPPoX socket is a for a regular session
* or the special tunnel type.
*/
static int pppol2tp_getsockopt(struct socket *sock, int level, int optname,
char __user *optval, int __user *optlen)
{
struct sock *sk = sock->sk;
struct l2tp_session *session;
struct l2tp_tunnel *tunnel;
int val, len;
int err;
if (level != SOL_PPPOL2TP)
return -EINVAL;
if (get_user(len, optlen))
return -EFAULT;
if (len < 0)
return -EINVAL;
len = min_t(unsigned int, len, sizeof(int));
err = -ENOTCONN;
if (!sk->sk_user_data)
goto end;
/* Get the session context */
err = -EBADF;
session = pppol2tp_sock_to_session(sk);
if (!session)
goto end;
/* Special case: if session_id == 0x0000, treat as operation on tunnel */
if (session->session_id == 0 && session->peer_session_id == 0) {
tunnel = session->tunnel;
err = pppol2tp_tunnel_getsockopt(sk, tunnel, optname, &val);
if (err)
goto end_put_sess;
} else {
err = pppol2tp_session_getsockopt(sk, session, optname, &val);
if (err)
goto end_put_sess;
}
err = -EFAULT;
if (put_user(len, optlen))
goto end_put_sess;
if (copy_to_user((void __user *)optval, &val, len))
goto end_put_sess;
err = 0;
end_put_sess:
l2tp_session_put(session);
end:
return err;
}
/*****************************************************************************
* /proc filesystem for debug
* Since the original pppol2tp driver provided /proc/net/pppol2tp for
* L2TPv2, we dump only L2TPv2 tunnels and sessions here.
*****************************************************************************/
#ifdef CONFIG_PROC_FS
struct pppol2tp_seq_data {
struct seq_net_private p;
unsigned long tkey; /* lookup key of current tunnel */
unsigned long skey; /* lookup key of current session */
struct l2tp_tunnel *tunnel;
struct l2tp_session *session; /* NULL means get next tunnel */
};
static void pppol2tp_next_tunnel(struct net *net, struct pppol2tp_seq_data *pd)
{
/* Drop reference taken during previous invocation */
if (pd->tunnel)
l2tp_tunnel_put(pd->tunnel);
for (;;) {
pd->tunnel = l2tp_tunnel_get_next(net, &pd->tkey);
pd->tkey++;
/* Only accept L2TPv2 tunnels */
if (!pd->tunnel || pd->tunnel->version == 2)
return;
l2tp_tunnel_put(pd->tunnel);
}
}
static void pppol2tp_next_session(struct net *net, struct pppol2tp_seq_data *pd)
{
/* Drop reference taken during previous invocation */
if (pd->session)
l2tp_session_put(pd->session);
pd->session = l2tp_session_get_next(net, pd->tunnel->sock,
pd->tunnel->version,
pd->tunnel->tunnel_id, &pd->skey);
pd->skey++;
if (!pd->session) {
pd->skey = 0;
pppol2tp_next_tunnel(net, pd);
}
}
static void *pppol2tp_seq_start(struct seq_file *m, loff_t *offs)
{
struct pppol2tp_seq_data *pd = SEQ_START_TOKEN;
loff_t pos = *offs;
struct net *net;
if (!pos)
goto out;
if (WARN_ON(!m->private)) {
pd = NULL;
goto out;
}
pd = m->private;
net = seq_file_net(m);
if (!pd->tunnel)
pppol2tp_next_tunnel(net, pd);
else
pppol2tp_next_session(net, pd);
/* NULL tunnel and session indicates end of list */
if (!pd->tunnel && !pd->session)
pd = NULL;
out:
return pd;
}
static void *pppol2tp_seq_next(struct seq_file *m, void *v, loff_t *pos)
{
(*pos)++;
return NULL;
}
static void pppol2tp_seq_stop(struct seq_file *p, void *v)
{
struct pppol2tp_seq_data *pd = v;
if (!pd || pd == SEQ_START_TOKEN)
return;
/* Drop reference taken by last invocation of pppol2tp_next_session()
* or pppol2tp_next_tunnel().
*/
if (pd->session) {
l2tp_session_put(pd->session);
pd->session = NULL;
}
if (pd->tunnel) {
l2tp_tunnel_put(pd->tunnel);
pd->tunnel = NULL;
}
}
static void pppol2tp_seq_tunnel_show(struct seq_file *m, void *v)
{
struct l2tp_tunnel *tunnel = v;
seq_printf(m, "\nTUNNEL '%s', %c %d\n",
tunnel->name,
tunnel->sock ? 'Y' : 'N',
refcount_read(&tunnel->ref_count) - 1);
seq_printf(m, " %08x %ld/%ld/%ld %ld/%ld/%ld\n",
0,
atomic_long_read(&tunnel->stats.tx_packets),
atomic_long_read(&tunnel->stats.tx_bytes),
atomic_long_read(&tunnel->stats.tx_errors),
atomic_long_read(&tunnel->stats.rx_packets),
atomic_long_read(&tunnel->stats.rx_bytes),
atomic_long_read(&tunnel->stats.rx_errors));
}
static void pppol2tp_seq_session_show(struct seq_file *m, void *v)
{
struct l2tp_session *session = v;
struct l2tp_tunnel *tunnel = session->tunnel;
unsigned char state;
char user_data_ok;
struct sock *sk;
u32 ip = 0;
u16 port = 0;
if (tunnel->sock) {
struct inet_sock *inet = inet_sk(tunnel->sock);
ip = ntohl(inet->inet_saddr);
port = ntohs(inet->inet_sport);
}
sk = pppol2tp_session_get_sock(session);
if (sk) {
state = sk->sk_state;
user_data_ok = (session == sk->sk_user_data) ? 'Y' : 'N';
} else {
state = 0;
user_data_ok = 'N';
}
seq_printf(m, " SESSION '%s' %08X/%d %04X/%04X -> %04X/%04X %d %c\n",
session->name, ip, port,
tunnel->tunnel_id,
session->session_id,
tunnel->peer_tunnel_id,
session->peer_session_id,
state, user_data_ok);
seq_printf(m, " 0/0/%c/%c/%s %08x %u\n",
session->recv_seq ? 'R' : '-',
session->send_seq ? 'S' : '-',
session->lns_mode ? "LNS" : "LAC",
0,
jiffies_to_msecs(session->reorder_timeout));
seq_printf(m, " %u/%u %ld/%ld/%ld %ld/%ld/%ld\n",
session->nr, session->ns,
atomic_long_read(&session->stats.tx_packets),
atomic_long_read(&session->stats.tx_bytes),
atomic_long_read(&session->stats.tx_errors),
atomic_long_read(&session->stats.rx_packets),
atomic_long_read(&session->stats.rx_bytes),
atomic_long_read(&session->stats.rx_errors));
if (sk) {
struct pppox_sock *po = pppox_sk(sk);
seq_printf(m, " interface %s\n", ppp_dev_name(&po->chan));
sock_put(sk);
}
}
static int pppol2tp_seq_show(struct seq_file *m, void *v)
{
struct pppol2tp_seq_data *pd = v;
/* display header on line 1 */
if (v == SEQ_START_TOKEN) {
seq_puts(m, "PPPoL2TP driver info, " PPPOL2TP_DRV_VERSION "\n");
seq_puts(m, "TUNNEL name, user-data-ok session-count\n");
seq_puts(m, " debug tx-pkts/bytes/errs rx-pkts/bytes/errs\n");
seq_puts(m, " SESSION name, addr/port src-tid/sid dest-tid/sid state user-data-ok\n");
seq_puts(m, " mtu/mru/rcvseq/sendseq/lns debug reorderto\n");
seq_puts(m, " nr/ns tx-pkts/bytes/errs rx-pkts/bytes/errs\n");
goto out;
}
if (!pd->session)
pppol2tp_seq_tunnel_show(m, pd->tunnel);
else
pppol2tp_seq_session_show(m, pd->session);
out:
return 0;
}
static const struct seq_operations pppol2tp_seq_ops = {
.start = pppol2tp_seq_start,
.next = pppol2tp_seq_next,
.stop = pppol2tp_seq_stop,
.show = pppol2tp_seq_show,
};
#endif /* CONFIG_PROC_FS */
/*****************************************************************************
* Network namespace
*****************************************************************************/
static __net_init int pppol2tp_init_net(struct net *net)
{
struct proc_dir_entry *pde;
int err = 0;
pde = proc_create_net("pppol2tp", 0444, net->proc_net,
&pppol2tp_seq_ops, sizeof(struct pppol2tp_seq_data));
if (!pde) {
err = -ENOMEM;
goto out;
}
out:
return err;
}
static __net_exit void pppol2tp_exit_net(struct net *net)
{
remove_proc_entry("pppol2tp", net->proc_net);
}
static struct pernet_operations pppol2tp_net_ops = {
.init = pppol2tp_init_net,
.exit = pppol2tp_exit_net,
};
/*****************************************************************************
* Init and cleanup
*****************************************************************************/
static const struct proto_ops pppol2tp_ops = {
.family = AF_PPPOX,
.owner = THIS_MODULE,
.release = pppol2tp_release,
.bind = sock_no_bind,
.connect = pppol2tp_connect,
.socketpair = sock_no_socketpair,
.accept = sock_no_accept,
.getname = pppol2tp_getname,
.poll = datagram_poll,
.listen = sock_no_listen,
.shutdown = sock_no_shutdown,
.setsockopt = pppol2tp_setsockopt,
.getsockopt = pppol2tp_getsockopt,
.sendmsg = pppol2tp_sendmsg,
.recvmsg = pppol2tp_recvmsg,
.mmap = sock_no_mmap,
.ioctl = pppox_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = pppox_compat_ioctl,
#endif
};
static const struct pppox_proto pppol2tp_proto = {
.create = pppol2tp_create,
.ioctl = pppol2tp_ioctl,
.owner = THIS_MODULE,
};
#ifdef CONFIG_L2TP_V3
static const struct l2tp_nl_cmd_ops pppol2tp_nl_cmd_ops = {
.session_create = pppol2tp_session_create,
.session_delete = l2tp_session_delete,
};
#endif /* CONFIG_L2TP_V3 */
static int __init pppol2tp_init(void)
{
int err;
err = register_pernet_device(&pppol2tp_net_ops);
if (err)
goto out;
err = proto_register(&pppol2tp_sk_proto, 0);
if (err)
goto out_unregister_pppol2tp_pernet;
err = register_pppox_proto(PX_PROTO_OL2TP, &pppol2tp_proto);
if (err)
goto out_unregister_pppol2tp_proto;
#ifdef CONFIG_L2TP_V3
err = l2tp_nl_register_ops(L2TP_PWTYPE_PPP, &pppol2tp_nl_cmd_ops);
if (err)
goto out_unregister_pppox;
#endif
pr_info("PPPoL2TP kernel driver, %s\n", PPPOL2TP_DRV_VERSION);
out:
return err;
#ifdef CONFIG_L2TP_V3
out_unregister_pppox:
unregister_pppox_proto(PX_PROTO_OL2TP);
#endif
out_unregister_pppol2tp_proto:
proto_unregister(&pppol2tp_sk_proto);
out_unregister_pppol2tp_pernet:
unregister_pernet_device(&pppol2tp_net_ops);
goto out;
}
static void __exit pppol2tp_exit(void)
{
#ifdef CONFIG_L2TP_V3
l2tp_nl_unregister_ops(L2TP_PWTYPE_PPP);
#endif
unregister_pppox_proto(PX_PROTO_OL2TP);
proto_unregister(&pppol2tp_sk_proto);
unregister_pernet_device(&pppol2tp_net_ops);
}
module_init(pppol2tp_init);
module_exit(pppol2tp_exit);
MODULE_AUTHOR("James Chapman <[email protected]>");
MODULE_DESCRIPTION("PPP over L2TP over UDP");
MODULE_LICENSE("GPL");
MODULE_VERSION(PPPOL2TP_DRV_VERSION);
MODULE_ALIAS_NET_PF_PROTO(PF_PPPOX, PX_PROTO_OL2TP);
MODULE_ALIAS_L2TP_PWTYPE(7);
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