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1735 lines
42 KiB
1735 lines
42 KiB
// 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) |
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* |
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* Version: 2.0.0 |
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* |
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* Authors: James Chapman ([email protected]) |
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* |
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* Based on original work by Martijn van Oosterhout <[email protected]> |
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* |
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* License: |
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*/ |
|
|
|
/* This driver handles only L2TP data frames; control frames are handled by a |
|
* userspace application. |
|
* |
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* To send data in an L2TP session, userspace opens a PPPoL2TP socket and |
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* attaches it to a bound UDP socket with local tunnel_id / session_id and |
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* peer tunnel_id / session_id set. Data can then be sent or received using |
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* regular socket sendmsg() / recvmsg() calls. Kernel parameters of the socket |
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* can be read or modified using ioctl() or [gs]etsockopt() calls. |
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* |
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* When a PPPoL2TP socket is connected with local and peer session_id values |
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* zero, the socket is treated as a special tunnel management socket. |
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* |
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* Here's example userspace code to create a socket for sending/receiving data |
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* over an L2TP session:- |
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* |
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* struct sockaddr_pppol2tp sax; |
|
* int fd; |
|
* int session_fd; |
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* |
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* fd = socket(AF_PPPOX, SOCK_DGRAM, PX_PROTO_OL2TP); |
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* |
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* sax.sa_family = AF_PPPOX; |
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* sax.sa_protocol = PX_PROTO_OL2TP; |
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* sax.pppol2tp.fd = tunnel_fd; // bound UDP socket |
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* sax.pppol2tp.addr.sin_addr.s_addr = addr->sin_addr.s_addr; |
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* sax.pppol2tp.addr.sin_port = addr->sin_port; |
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* sax.pppol2tp.addr.sin_family = AF_INET; |
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* sax.pppol2tp.s_tunnel = tunnel_id; |
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* sax.pppol2tp.s_session = session_id; |
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* sax.pppol2tp.d_tunnel = peer_tunnel_id; |
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* sax.pppol2tp.d_session = peer_session_id; |
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* |
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* session_fd = connect(fd, (struct sockaddr *)&sax, sizeof(sax)); |
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* |
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* A pppd plugin that allows PPP traffic to be carried over L2TP using |
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* this driver is available from the OpenL2TP project at |
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* http://openl2tp.sourceforge.net. |
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*/ |
|
|
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
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|
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#include <linux/module.h> |
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#include <linux/string.h> |
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#include <linux/list.h> |
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#include <linux/uaccess.h> |
|
|
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#include <linux/kernel.h> |
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#include <linux/spinlock.h> |
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#include <linux/kthread.h> |
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#include <linux/sched.h> |
|
#include <linux/slab.h> |
|
#include <linux/errno.h> |
|
#include <linux/jiffies.h> |
|
|
|
#include <linux/netdevice.h> |
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#include <linux/net.h> |
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#include <linux/inetdevice.h> |
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#include <linux/skbuff.h> |
|
#include <linux/init.h> |
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#include <linux/ip.h> |
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#include <linux/udp.h> |
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#include <linux/if_pppox.h> |
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#include <linux/if_pppol2tp.h> |
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#include <net/sock.h> |
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#include <linux/ppp_channel.h> |
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#include <linux/ppp_defs.h> |
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#include <linux/ppp-ioctl.h> |
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#include <linux/file.h> |
|
#include <linux/hash.h> |
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#include <linux/sort.h> |
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#include <linux/proc_fs.h> |
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#include <linux/l2tp.h> |
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#include <linux/nsproxy.h> |
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#include <net/net_namespace.h> |
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#include <net/netns/generic.h> |
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#include <net/ip.h> |
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#include <net/udp.h> |
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#include <net/inet_common.h> |
|
|
|
#include <asm/byteorder.h> |
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#include <linux/atomic.h> |
|
|
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#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. |
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* Unfortunately the size is different depending on whether sequence numbers |
|
* are enabled. |
|
*/ |
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#define PPPOL2TP_L2TP_HDR_SIZE_SEQ 10 |
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#define PPPOL2TP_L2TP_HDR_SIZE_NOSEQ 6 |
|
|
|
/* Private data of each session. This data lives at the end of struct |
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* l2tp_session, referenced via session->priv[]. |
|
*/ |
|
struct pppol2tp_session { |
|
int owner; /* pid that opened the socket */ |
|
|
|
struct mutex sk_lock; /* Protects .sk */ |
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struct sock __rcu *sk; /* Pointer to the session PPPoX socket */ |
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struct sock *__sk; /* Copy of .sk, for cleanup */ |
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struct rcu_head rcu; /* For asynchronous release */ |
|
}; |
|
|
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static int pppol2tp_xmit(struct ppp_channel *chan, struct sk_buff *skb); |
|
|
|
static const struct ppp_channel_ops pppol2tp_chan_ops = { |
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.start_xmit = pppol2tp_xmit, |
|
}; |
|
|
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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 inline struct l2tp_session *pppol2tp_sock_to_session(struct sock *sk) |
|
{ |
|
struct l2tp_session *session; |
|
|
|
if (!sk) |
|
return NULL; |
|
|
|
sock_hold(sk); |
|
session = (struct l2tp_session *)(sk->sk_user_data); |
|
if (!session) { |
|
sock_put(sk); |
|
goto out; |
|
} |
|
if (WARN_ON(session->magic != L2TP_SESSION_MAGIC)) { |
|
session = NULL; |
|
sock_put(sk); |
|
goto out; |
|
} |
|
|
|
out: |
|
return session; |
|
} |
|
|
|
/***************************************************************************** |
|
* 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 & ~MSG_DONTWAIT, |
|
flags & MSG_DONTWAIT, &err); |
|
if (!skb) |
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goto end; |
|
|
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if (len > skb->len) |
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len = skb->len; |
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else if (len < skb->len) |
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msg->msg_flags |= MSG_TRUNC; |
|
|
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err = skb_copy_datagram_msg(skb, 0, msg, len); |
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if (likely(err == 0)) |
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err = len; |
|
|
|
kfree_skb(skb); |
|
end: |
|
return err; |
|
} |
|
|
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static void pppol2tp_recv(struct l2tp_session *session, struct sk_buff *skb, int data_len) |
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{ |
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struct pppol2tp_session *ps = l2tp_session_priv(session); |
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struct sock *sk = NULL; |
|
|
|
/* If the socket is bound, send it in to PPP's input queue. Otherwise |
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* queue it on the session socket. |
|
*/ |
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rcu_read_lock(); |
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sk = rcu_dereference(ps->sk); |
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if (!sk) |
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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 && |
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skb->data[1] == PPP_UI) |
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skb_pull(skb, 2); |
|
|
|
if (sk->sk_state & PPPOX_BOUND) { |
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struct pppox_sock *po; |
|
|
|
po = pppox_sk(sk); |
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ppp_input(&po->chan, skb); |
|
} else { |
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if (sock_queue_rcv_skb(sk, skb) < 0) { |
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atomic_long_inc(&session->stats.rx_errors); |
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kfree_skb(skb); |
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} |
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} |
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rcu_read_unlock(); |
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|
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return; |
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|
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no_sock: |
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rcu_read_unlock(); |
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pr_warn_ratelimited("%s: no socket in recv\n", session->name); |
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kfree_skb(skb); |
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} |
|
|
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/************************************************************************ |
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* Transmit handling |
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***********************************************************************/ |
|
|
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/* This is the sendmsg for the PPPoL2TP pppol2tp_session socket. We come here |
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* when a user application does a sendmsg() on the session socket. L2TP and |
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* PPP headers must be inserted into the user's data. |
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*/ |
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static int pppol2tp_sendmsg(struct socket *sock, struct msghdr *m, |
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size_t total_len) |
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{ |
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struct sock *sk = sock->sk; |
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struct sk_buff *skb; |
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int error; |
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struct l2tp_session *session; |
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struct l2tp_tunnel *tunnel; |
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int uhlen; |
|
|
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error = -ENOTCONN; |
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if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED)) |
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goto error; |
|
|
|
/* Get session and tunnel contexts */ |
|
error = -EBADF; |
|
session = pppol2tp_sock_to_session(sk); |
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if (!session) |
|
goto error; |
|
|
|
tunnel = session->tunnel; |
|
|
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uhlen = (tunnel->encap == L2TP_ENCAPTYPE_UDP) ? sizeof(struct udphdr) : 0; |
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|
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/* Allocate a socket buffer */ |
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error = -ENOMEM; |
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skb = sock_wmalloc(sk, NET_SKB_PAD + sizeof(struct iphdr) + |
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uhlen + session->hdr_len + |
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2 + total_len, /* 2 bytes for PPP_ALLSTATIONS & PPP_UI */ |
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0, GFP_KERNEL); |
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if (!skb) |
|
goto error_put_sess; |
|
|
|
/* Reserve space for headers. */ |
|
skb_reserve(skb, NET_SKB_PAD); |
|
skb_reset_network_header(skb); |
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skb_reserve(skb, sizeof(struct iphdr)); |
|
skb_reset_transport_header(skb); |
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skb_reserve(skb, uhlen); |
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|
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/* Add PPP header */ |
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skb->data[0] = PPP_ALLSTATIONS; |
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skb->data[1] = PPP_UI; |
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skb_put(skb, 2); |
|
|
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/* Copy user data into skb */ |
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error = memcpy_from_msg(skb_put(skb, total_len), m, total_len); |
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if (error < 0) { |
|
kfree_skb(skb); |
|
goto error_put_sess; |
|
} |
|
|
|
local_bh_disable(); |
|
l2tp_xmit_skb(session, skb); |
|
local_bh_enable(); |
|
|
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sock_put(sk); |
|
|
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return total_len; |
|
|
|
error_put_sess: |
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sock_put(sk); |
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error: |
|
return error; |
|
} |
|
|
|
/* Transmit function called by generic PPP driver. Sends PPP frame |
|
* over PPPoL2TP socket. |
|
* |
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* 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(); |
|
|
|
sock_put(sk); |
|
|
|
return 1; |
|
|
|
abort_put_sess: |
|
sock_put(sk); |
|
abort: |
|
/* Free the original skb */ |
|
kfree_skb(skb); |
|
return 1; |
|
} |
|
|
|
/***************************************************************************** |
|
* Session (and tunnel control) socket create/destroy. |
|
*****************************************************************************/ |
|
|
|
static void pppol2tp_put_sk(struct rcu_head *head) |
|
{ |
|
struct pppol2tp_session *ps; |
|
|
|
ps = container_of(head, typeof(*ps), rcu); |
|
sock_put(ps->__sk); |
|
} |
|
|
|
/* Really kill the session socket. (Called from sock_put() if |
|
* refcnt == 0.) |
|
*/ |
|
static void pppol2tp_session_destruct(struct sock *sk) |
|
{ |
|
struct l2tp_session *session = sk->sk_user_data; |
|
|
|
skb_queue_purge(&sk->sk_receive_queue); |
|
skb_queue_purge(&sk->sk_write_queue); |
|
|
|
if (session) { |
|
sk->sk_user_data = NULL; |
|
if (WARN_ON(session->magic != L2TP_SESSION_MAGIC)) |
|
return; |
|
l2tp_session_dec_refcount(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) { |
|
struct pppol2tp_session *ps; |
|
|
|
l2tp_session_delete(session); |
|
|
|
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); |
|
call_rcu(&ps->rcu, pppol2tp_put_sk); |
|
|
|
/* Rely on the sock_put() call at the end of the function for |
|
* dropping the reference held by pppol2tp_sock_to_session(). |
|
* The last reference will be dropped by pppol2tp_put_sk(). |
|
*/ |
|
} |
|
|
|
release_sock(sk); |
|
|
|
/* This will delete the session context via |
|
* pppol2tp_session_destruct() if the socket's refcnt drops to |
|
* zero. |
|
*/ |
|
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->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; |
|
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; |
|
} |
|
|
|
/* 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 drop_tunnel = 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; |
|
|
|
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 */ |
|
|
|
/* Don't bind if tunnel_id is 0 */ |
|
error = -EINVAL; |
|
if (!info.tunnel_id) |
|
goto end; |
|
|
|
tunnel = l2tp_tunnel_get(sock_net(sk), info.tunnel_id); |
|
if (tunnel) |
|
drop_tunnel = true; |
|
|
|
/* 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) { |
|
error = -EBADF; |
|
goto end; |
|
} |
|
|
|
error = l2tp_tunnel_create(info.fd, |
|
info.version, |
|
info.tunnel_id, |
|
info.peer_tunnel_id, &tcfg, |
|
&tunnel); |
|
if (error < 0) |
|
goto end; |
|
|
|
l2tp_tunnel_inc_refcount(tunnel); |
|
error = l2tp_tunnel_register(tunnel, sock_net(sk), |
|
&tcfg); |
|
if (error < 0) { |
|
kfree(tunnel); |
|
goto end; |
|
} |
|
drop_tunnel = true; |
|
new_tunnel = true; |
|
} |
|
} else { |
|
/* Error if we can't find the tunnel */ |
|
error = -ENOENT; |
|
if (!tunnel) |
|
goto end; |
|
|
|
/* Error if socket is not prepped */ |
|
if (!tunnel->sock) |
|
goto end; |
|
} |
|
|
|
if (tunnel->peer_tunnel_id == 0) |
|
tunnel->peer_tunnel_id = info.peer_tunnel_id; |
|
|
|
session = l2tp_tunnel_get_session(tunnel, 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; |
|
} |
|
|
|
pppol2tp_session_init(session); |
|
ps = l2tp_session_priv(session); |
|
l2tp_session_inc_refcount(session); |
|
|
|
mutex_lock(&ps->sk_lock); |
|
error = l2tp_session_register(session, tunnel); |
|
if (error < 0) { |
|
mutex_unlock(&ps->sk_lock); |
|
kfree(session); |
|
goto end; |
|
} |
|
drop_refcnt = true; |
|
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. */ |
|
sk->sk_user_data = 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_destruct() 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_dec_refcount(session); |
|
if (drop_tunnel) |
|
l2tp_tunnel_dec_refcount(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: |
|
kfree(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; |
|
|
|
sock_put(sk); |
|
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_tunnel_get_session(tunnel, stats->session_id); |
|
if (!session) |
|
return -EBADR; |
|
|
|
if (session->pwtype != L2TP_PWTYPE_PPP) { |
|
l2tp_session_dec_refcount(session); |
|
return -EBADR; |
|
} |
|
|
|
pppol2tp_copy_stats(stats, &session->stats); |
|
l2tp_session_dec_refcount(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); |
|
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); |
|
} |
|
|
|
sock_put(sk); |
|
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; |
|
|
|
len = min_t(unsigned int, len, sizeof(int)); |
|
|
|
if (len < 0) |
|
return -EINVAL; |
|
|
|
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: |
|
sock_put(sk); |
|
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. |
|
*****************************************************************************/ |
|
|
|
static unsigned int pppol2tp_net_id; |
|
|
|
#ifdef CONFIG_PROC_FS |
|
|
|
struct pppol2tp_seq_data { |
|
struct seq_net_private p; |
|
int tunnel_idx; /* current tunnel */ |
|
int session_idx; /* index of session within current tunnel */ |
|
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_dec_refcount(pd->tunnel); |
|
|
|
for (;;) { |
|
pd->tunnel = l2tp_tunnel_get_nth(net, pd->tunnel_idx); |
|
pd->tunnel_idx++; |
|
|
|
/* Only accept L2TPv2 tunnels */ |
|
if (!pd->tunnel || pd->tunnel->version == 2) |
|
return; |
|
|
|
l2tp_tunnel_dec_refcount(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_dec_refcount(pd->session); |
|
|
|
pd->session = l2tp_session_get_nth(pd->tunnel, pd->session_idx); |
|
pd->session_idx++; |
|
|
|
if (!pd->session) { |
|
pd->session_idx = 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_dec_refcount(pd->session); |
|
pd->session = NULL; |
|
} |
|
if (pd->tunnel) { |
|
l2tp_tunnel_dec_refcount(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 == tunnel->sock->sk_user_data) ? '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, " %hu/%hu %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, |
|
.id = &pppol2tp_net_id, |
|
}; |
|
|
|
/***************************************************************************** |
|
* 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); |
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} |
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|
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module_init(pppol2tp_init); |
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module_exit(pppol2tp_exit); |
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|
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MODULE_AUTHOR("James Chapman <[email protected]>"); |
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MODULE_DESCRIPTION("PPP over L2TP over UDP"); |
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MODULE_LICENSE("GPL"); |
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MODULE_VERSION(PPPOL2TP_DRV_VERSION); |
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MODULE_ALIAS_NET_PF_PROTO(PF_PPPOX, PX_PROTO_OL2TP); |
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MODULE_ALIAS_L2TP_PWTYPE(7);
|
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|