linux/drivers/isdn/mISDN/socket.c
Thomas Gleixner 1802d0beec treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation this program is
  distributed in the hope that it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 655 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070034.575739538@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:41 -07:00

825 lines
17 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
*
* Author Karsten Keil <kkeil@novell.com>
*
* Copyright 2008 by Karsten Keil <kkeil@novell.com>
*/
#include <linux/mISDNif.h>
#include <linux/slab.h>
#include <linux/export.h>
#include "core.h"
static u_int *debug;
static struct proto mISDN_proto = {
.name = "misdn",
.owner = THIS_MODULE,
.obj_size = sizeof(struct mISDN_sock)
};
#define _pms(sk) ((struct mISDN_sock *)sk)
static struct mISDN_sock_list data_sockets = {
.lock = __RW_LOCK_UNLOCKED(data_sockets.lock)
};
static struct mISDN_sock_list base_sockets = {
.lock = __RW_LOCK_UNLOCKED(base_sockets.lock)
};
#define L2_HEADER_LEN 4
static inline struct sk_buff *
_l2_alloc_skb(unsigned int len, gfp_t gfp_mask)
{
struct sk_buff *skb;
skb = alloc_skb(len + L2_HEADER_LEN, gfp_mask);
if (likely(skb))
skb_reserve(skb, L2_HEADER_LEN);
return skb;
}
static void
mISDN_sock_link(struct mISDN_sock_list *l, struct sock *sk)
{
write_lock_bh(&l->lock);
sk_add_node(sk, &l->head);
write_unlock_bh(&l->lock);
}
static void mISDN_sock_unlink(struct mISDN_sock_list *l, struct sock *sk)
{
write_lock_bh(&l->lock);
sk_del_node_init(sk);
write_unlock_bh(&l->lock);
}
static int
mISDN_send(struct mISDNchannel *ch, struct sk_buff *skb)
{
struct mISDN_sock *msk;
int err;
msk = container_of(ch, struct mISDN_sock, ch);
if (*debug & DEBUG_SOCKET)
printk(KERN_DEBUG "%s len %d %p\n", __func__, skb->len, skb);
if (msk->sk.sk_state == MISDN_CLOSED)
return -EUNATCH;
__net_timestamp(skb);
err = sock_queue_rcv_skb(&msk->sk, skb);
if (err)
printk(KERN_WARNING "%s: error %d\n", __func__, err);
return err;
}
static int
mISDN_ctrl(struct mISDNchannel *ch, u_int cmd, void *arg)
{
struct mISDN_sock *msk;
msk = container_of(ch, struct mISDN_sock, ch);
if (*debug & DEBUG_SOCKET)
printk(KERN_DEBUG "%s(%p, %x, %p)\n", __func__, ch, cmd, arg);
switch (cmd) {
case CLOSE_CHANNEL:
msk->sk.sk_state = MISDN_CLOSED;
break;
}
return 0;
}
static inline void
mISDN_sock_cmsg(struct sock *sk, struct msghdr *msg, struct sk_buff *skb)
{
struct __kernel_old_timeval tv;
if (_pms(sk)->cmask & MISDN_TIME_STAMP) {
skb_get_timestamp(skb, &tv);
put_cmsg(msg, SOL_MISDN, MISDN_TIME_STAMP, sizeof(tv), &tv);
}
}
static int
mISDN_sock_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
int flags)
{
struct sk_buff *skb;
struct sock *sk = sock->sk;
int copied, err;
if (*debug & DEBUG_SOCKET)
printk(KERN_DEBUG "%s: len %d, flags %x ch.nr %d, proto %x\n",
__func__, (int)len, flags, _pms(sk)->ch.nr,
sk->sk_protocol);
if (flags & (MSG_OOB))
return -EOPNOTSUPP;
if (sk->sk_state == MISDN_CLOSED)
return 0;
skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
if (!skb)
return err;
if (msg->msg_name) {
DECLARE_SOCKADDR(struct sockaddr_mISDN *, maddr, msg->msg_name);
maddr->family = AF_ISDN;
maddr->dev = _pms(sk)->dev->id;
if ((sk->sk_protocol == ISDN_P_LAPD_TE) ||
(sk->sk_protocol == ISDN_P_LAPD_NT)) {
maddr->channel = (mISDN_HEAD_ID(skb) >> 16) & 0xff;
maddr->tei = (mISDN_HEAD_ID(skb) >> 8) & 0xff;
maddr->sapi = mISDN_HEAD_ID(skb) & 0xff;
} else {
maddr->channel = _pms(sk)->ch.nr;
maddr->sapi = _pms(sk)->ch.addr & 0xFF;
maddr->tei = (_pms(sk)->ch.addr >> 8) & 0xFF;
}
msg->msg_namelen = sizeof(*maddr);
}
copied = skb->len + MISDN_HEADER_LEN;
if (len < copied) {
if (flags & MSG_PEEK)
refcount_dec(&skb->users);
else
skb_queue_head(&sk->sk_receive_queue, skb);
return -ENOSPC;
}
memcpy(skb_push(skb, MISDN_HEADER_LEN), mISDN_HEAD_P(skb),
MISDN_HEADER_LEN);
err = skb_copy_datagram_msg(skb, 0, msg, copied);
mISDN_sock_cmsg(sk, msg, skb);
skb_free_datagram(sk, skb);
return err ? : copied;
}
static int
mISDN_sock_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
{
struct sock *sk = sock->sk;
struct sk_buff *skb;
int err = -ENOMEM;
if (*debug & DEBUG_SOCKET)
printk(KERN_DEBUG "%s: len %d flags %x ch %d proto %x\n",
__func__, (int)len, msg->msg_flags, _pms(sk)->ch.nr,
sk->sk_protocol);
if (msg->msg_flags & MSG_OOB)
return -EOPNOTSUPP;
if (msg->msg_flags & ~(MSG_DONTWAIT | MSG_NOSIGNAL | MSG_ERRQUEUE))
return -EINVAL;
if (len < MISDN_HEADER_LEN)
return -EINVAL;
if (sk->sk_state != MISDN_BOUND)
return -EBADFD;
lock_sock(sk);
skb = _l2_alloc_skb(len, GFP_KERNEL);
if (!skb)
goto done;
if (memcpy_from_msg(skb_put(skb, len), msg, len)) {
err = -EFAULT;
goto done;
}
memcpy(mISDN_HEAD_P(skb), skb->data, MISDN_HEADER_LEN);
skb_pull(skb, MISDN_HEADER_LEN);
if (msg->msg_namelen >= sizeof(struct sockaddr_mISDN)) {
/* if we have a address, we use it */
DECLARE_SOCKADDR(struct sockaddr_mISDN *, maddr, msg->msg_name);
mISDN_HEAD_ID(skb) = maddr->channel;
} else { /* use default for L2 messages */
if ((sk->sk_protocol == ISDN_P_LAPD_TE) ||
(sk->sk_protocol == ISDN_P_LAPD_NT))
mISDN_HEAD_ID(skb) = _pms(sk)->ch.nr;
}
if (*debug & DEBUG_SOCKET)
printk(KERN_DEBUG "%s: ID:%x\n",
__func__, mISDN_HEAD_ID(skb));
err = -ENODEV;
if (!_pms(sk)->ch.peer)
goto done;
err = _pms(sk)->ch.recv(_pms(sk)->ch.peer, skb);
if (err)
goto done;
else {
skb = NULL;
err = len;
}
done:
kfree_skb(skb);
release_sock(sk);
return err;
}
static int
data_sock_release(struct socket *sock)
{
struct sock *sk = sock->sk;
if (*debug & DEBUG_SOCKET)
printk(KERN_DEBUG "%s(%p) sk=%p\n", __func__, sock, sk);
if (!sk)
return 0;
switch (sk->sk_protocol) {
case ISDN_P_TE_S0:
case ISDN_P_NT_S0:
case ISDN_P_TE_E1:
case ISDN_P_NT_E1:
if (sk->sk_state == MISDN_BOUND)
delete_channel(&_pms(sk)->ch);
else
mISDN_sock_unlink(&data_sockets, sk);
break;
case ISDN_P_LAPD_TE:
case ISDN_P_LAPD_NT:
case ISDN_P_B_RAW:
case ISDN_P_B_HDLC:
case ISDN_P_B_X75SLP:
case ISDN_P_B_L2DTMF:
case ISDN_P_B_L2DSP:
case ISDN_P_B_L2DSPHDLC:
delete_channel(&_pms(sk)->ch);
mISDN_sock_unlink(&data_sockets, sk);
break;
}
lock_sock(sk);
sock_orphan(sk);
skb_queue_purge(&sk->sk_receive_queue);
release_sock(sk);
sock_put(sk);
return 0;
}
static int
data_sock_ioctl_bound(struct sock *sk, unsigned int cmd, void __user *p)
{
struct mISDN_ctrl_req cq;
int err = -EINVAL, val[2];
struct mISDNchannel *bchan, *next;
lock_sock(sk);
if (!_pms(sk)->dev) {
err = -ENODEV;
goto done;
}
switch (cmd) {
case IMCTRLREQ:
if (copy_from_user(&cq, p, sizeof(cq))) {
err = -EFAULT;
break;
}
if ((sk->sk_protocol & ~ISDN_P_B_MASK) == ISDN_P_B_START) {
list_for_each_entry_safe(bchan, next,
&_pms(sk)->dev->bchannels, list) {
if (bchan->nr == cq.channel) {
err = bchan->ctrl(bchan,
CONTROL_CHANNEL, &cq);
break;
}
}
} else
err = _pms(sk)->dev->D.ctrl(&_pms(sk)->dev->D,
CONTROL_CHANNEL, &cq);
if (err)
break;
if (copy_to_user(p, &cq, sizeof(cq)))
err = -EFAULT;
break;
case IMCLEAR_L2:
if (sk->sk_protocol != ISDN_P_LAPD_NT) {
err = -EINVAL;
break;
}
val[0] = cmd;
if (get_user(val[1], (int __user *)p)) {
err = -EFAULT;
break;
}
err = _pms(sk)->dev->teimgr->ctrl(_pms(sk)->dev->teimgr,
CONTROL_CHANNEL, val);
break;
case IMHOLD_L1:
if (sk->sk_protocol != ISDN_P_LAPD_NT
&& sk->sk_protocol != ISDN_P_LAPD_TE) {
err = -EINVAL;
break;
}
val[0] = cmd;
if (get_user(val[1], (int __user *)p)) {
err = -EFAULT;
break;
}
err = _pms(sk)->dev->teimgr->ctrl(_pms(sk)->dev->teimgr,
CONTROL_CHANNEL, val);
break;
default:
err = -EINVAL;
break;
}
done:
release_sock(sk);
return err;
}
static int
data_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
{
int err = 0, id;
struct sock *sk = sock->sk;
struct mISDNdevice *dev;
struct mISDNversion ver;
switch (cmd) {
case IMGETVERSION:
ver.major = MISDN_MAJOR_VERSION;
ver.minor = MISDN_MINOR_VERSION;
ver.release = MISDN_RELEASE;
if (copy_to_user((void __user *)arg, &ver, sizeof(ver)))
err = -EFAULT;
break;
case IMGETCOUNT:
id = get_mdevice_count();
if (put_user(id, (int __user *)arg))
err = -EFAULT;
break;
case IMGETDEVINFO:
if (get_user(id, (int __user *)arg)) {
err = -EFAULT;
break;
}
dev = get_mdevice(id);
if (dev) {
struct mISDN_devinfo di;
memset(&di, 0, sizeof(di));
di.id = dev->id;
di.Dprotocols = dev->Dprotocols;
di.Bprotocols = dev->Bprotocols | get_all_Bprotocols();
di.protocol = dev->D.protocol;
memcpy(di.channelmap, dev->channelmap,
sizeof(di.channelmap));
di.nrbchan = dev->nrbchan;
strcpy(di.name, dev_name(&dev->dev));
if (copy_to_user((void __user *)arg, &di, sizeof(di)))
err = -EFAULT;
} else
err = -ENODEV;
break;
default:
if (sk->sk_state == MISDN_BOUND)
err = data_sock_ioctl_bound(sk, cmd,
(void __user *)arg);
else
err = -ENOTCONN;
}
return err;
}
static int data_sock_setsockopt(struct socket *sock, int level, int optname,
char __user *optval, unsigned int len)
{
struct sock *sk = sock->sk;
int err = 0, opt = 0;
if (*debug & DEBUG_SOCKET)
printk(KERN_DEBUG "%s(%p, %d, %x, %p, %d)\n", __func__, sock,
level, optname, optval, len);
lock_sock(sk);
switch (optname) {
case MISDN_TIME_STAMP:
if (get_user(opt, (int __user *)optval)) {
err = -EFAULT;
break;
}
if (opt)
_pms(sk)->cmask |= MISDN_TIME_STAMP;
else
_pms(sk)->cmask &= ~MISDN_TIME_STAMP;
break;
default:
err = -ENOPROTOOPT;
break;
}
release_sock(sk);
return err;
}
static int data_sock_getsockopt(struct socket *sock, int level, int optname,
char __user *optval, int __user *optlen)
{
struct sock *sk = sock->sk;
int len, opt;
if (get_user(len, optlen))
return -EFAULT;
if (len != sizeof(char))
return -EINVAL;
switch (optname) {
case MISDN_TIME_STAMP:
if (_pms(sk)->cmask & MISDN_TIME_STAMP)
opt = 1;
else
opt = 0;
if (put_user(opt, optval))
return -EFAULT;
break;
default:
return -ENOPROTOOPT;
}
return 0;
}
static int
data_sock_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
{
struct sockaddr_mISDN *maddr = (struct sockaddr_mISDN *) addr;
struct sock *sk = sock->sk;
struct sock *csk;
int err = 0;
if (*debug & DEBUG_SOCKET)
printk(KERN_DEBUG "%s(%p) sk=%p\n", __func__, sock, sk);
if (addr_len != sizeof(struct sockaddr_mISDN))
return -EINVAL;
if (!maddr || maddr->family != AF_ISDN)
return -EINVAL;
lock_sock(sk);
if (_pms(sk)->dev) {
err = -EALREADY;
goto done;
}
_pms(sk)->dev = get_mdevice(maddr->dev);
if (!_pms(sk)->dev) {
err = -ENODEV;
goto done;
}
if (sk->sk_protocol < ISDN_P_B_START) {
read_lock_bh(&data_sockets.lock);
sk_for_each(csk, &data_sockets.head) {
if (sk == csk)
continue;
if (_pms(csk)->dev != _pms(sk)->dev)
continue;
if (csk->sk_protocol >= ISDN_P_B_START)
continue;
if (IS_ISDN_P_TE(csk->sk_protocol)
== IS_ISDN_P_TE(sk->sk_protocol))
continue;
read_unlock_bh(&data_sockets.lock);
err = -EBUSY;
goto done;
}
read_unlock_bh(&data_sockets.lock);
}
_pms(sk)->ch.send = mISDN_send;
_pms(sk)->ch.ctrl = mISDN_ctrl;
switch (sk->sk_protocol) {
case ISDN_P_TE_S0:
case ISDN_P_NT_S0:
case ISDN_P_TE_E1:
case ISDN_P_NT_E1:
mISDN_sock_unlink(&data_sockets, sk);
err = connect_layer1(_pms(sk)->dev, &_pms(sk)->ch,
sk->sk_protocol, maddr);
if (err)
mISDN_sock_link(&data_sockets, sk);
break;
case ISDN_P_LAPD_TE:
case ISDN_P_LAPD_NT:
err = create_l2entity(_pms(sk)->dev, &_pms(sk)->ch,
sk->sk_protocol, maddr);
break;
case ISDN_P_B_RAW:
case ISDN_P_B_HDLC:
case ISDN_P_B_X75SLP:
case ISDN_P_B_L2DTMF:
case ISDN_P_B_L2DSP:
case ISDN_P_B_L2DSPHDLC:
err = connect_Bstack(_pms(sk)->dev, &_pms(sk)->ch,
sk->sk_protocol, maddr);
break;
default:
err = -EPROTONOSUPPORT;
}
if (err)
goto done;
sk->sk_state = MISDN_BOUND;
_pms(sk)->ch.protocol = sk->sk_protocol;
done:
release_sock(sk);
return err;
}
static int
data_sock_getname(struct socket *sock, struct sockaddr *addr,
int peer)
{
struct sockaddr_mISDN *maddr = (struct sockaddr_mISDN *) addr;
struct sock *sk = sock->sk;
if (!_pms(sk)->dev)
return -EBADFD;
lock_sock(sk);
maddr->family = AF_ISDN;
maddr->dev = _pms(sk)->dev->id;
maddr->channel = _pms(sk)->ch.nr;
maddr->sapi = _pms(sk)->ch.addr & 0xff;
maddr->tei = (_pms(sk)->ch.addr >> 8) & 0xff;
release_sock(sk);
return sizeof(*maddr);
}
static const struct proto_ops data_sock_ops = {
.family = PF_ISDN,
.owner = THIS_MODULE,
.release = data_sock_release,
.ioctl = data_sock_ioctl,
.bind = data_sock_bind,
.getname = data_sock_getname,
.sendmsg = mISDN_sock_sendmsg,
.recvmsg = mISDN_sock_recvmsg,
.poll = datagram_poll,
.listen = sock_no_listen,
.shutdown = sock_no_shutdown,
.setsockopt = data_sock_setsockopt,
.getsockopt = data_sock_getsockopt,
.connect = sock_no_connect,
.socketpair = sock_no_socketpair,
.accept = sock_no_accept,
.mmap = sock_no_mmap
};
static int
data_sock_create(struct net *net, struct socket *sock, int protocol, int kern)
{
struct sock *sk;
if (sock->type != SOCK_DGRAM)
return -ESOCKTNOSUPPORT;
sk = sk_alloc(net, PF_ISDN, GFP_KERNEL, &mISDN_proto, kern);
if (!sk)
return -ENOMEM;
sock_init_data(sock, sk);
sock->ops = &data_sock_ops;
sock->state = SS_UNCONNECTED;
sock_reset_flag(sk, SOCK_ZAPPED);
sk->sk_protocol = protocol;
sk->sk_state = MISDN_OPEN;
mISDN_sock_link(&data_sockets, sk);
return 0;
}
static int
base_sock_release(struct socket *sock)
{
struct sock *sk = sock->sk;
printk(KERN_DEBUG "%s(%p) sk=%p\n", __func__, sock, sk);
if (!sk)
return 0;
mISDN_sock_unlink(&base_sockets, sk);
sock_orphan(sk);
sock_put(sk);
return 0;
}
static int
base_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
{
int err = 0, id;
struct mISDNdevice *dev;
struct mISDNversion ver;
switch (cmd) {
case IMGETVERSION:
ver.major = MISDN_MAJOR_VERSION;
ver.minor = MISDN_MINOR_VERSION;
ver.release = MISDN_RELEASE;
if (copy_to_user((void __user *)arg, &ver, sizeof(ver)))
err = -EFAULT;
break;
case IMGETCOUNT:
id = get_mdevice_count();
if (put_user(id, (int __user *)arg))
err = -EFAULT;
break;
case IMGETDEVINFO:
if (get_user(id, (int __user *)arg)) {
err = -EFAULT;
break;
}
dev = get_mdevice(id);
if (dev) {
struct mISDN_devinfo di;
memset(&di, 0, sizeof(di));
di.id = dev->id;
di.Dprotocols = dev->Dprotocols;
di.Bprotocols = dev->Bprotocols | get_all_Bprotocols();
di.protocol = dev->D.protocol;
memcpy(di.channelmap, dev->channelmap,
sizeof(di.channelmap));
di.nrbchan = dev->nrbchan;
strcpy(di.name, dev_name(&dev->dev));
if (copy_to_user((void __user *)arg, &di, sizeof(di)))
err = -EFAULT;
} else
err = -ENODEV;
break;
case IMSETDEVNAME:
{
struct mISDN_devrename dn;
if (copy_from_user(&dn, (void __user *)arg,
sizeof(dn))) {
err = -EFAULT;
break;
}
dev = get_mdevice(dn.id);
if (dev)
err = device_rename(&dev->dev, dn.name);
else
err = -ENODEV;
}
break;
default:
err = -EINVAL;
}
return err;
}
static int
base_sock_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
{
struct sockaddr_mISDN *maddr = (struct sockaddr_mISDN *) addr;
struct sock *sk = sock->sk;
int err = 0;
if (addr_len < sizeof(struct sockaddr_mISDN))
return -EINVAL;
if (!maddr || maddr->family != AF_ISDN)
return -EINVAL;
lock_sock(sk);
if (_pms(sk)->dev) {
err = -EALREADY;
goto done;
}
_pms(sk)->dev = get_mdevice(maddr->dev);
if (!_pms(sk)->dev) {
err = -ENODEV;
goto done;
}
sk->sk_state = MISDN_BOUND;
done:
release_sock(sk);
return err;
}
static const struct proto_ops base_sock_ops = {
.family = PF_ISDN,
.owner = THIS_MODULE,
.release = base_sock_release,
.ioctl = base_sock_ioctl,
.bind = base_sock_bind,
.getname = sock_no_getname,
.sendmsg = sock_no_sendmsg,
.recvmsg = sock_no_recvmsg,
.listen = sock_no_listen,
.shutdown = sock_no_shutdown,
.setsockopt = sock_no_setsockopt,
.getsockopt = sock_no_getsockopt,
.connect = sock_no_connect,
.socketpair = sock_no_socketpair,
.accept = sock_no_accept,
.mmap = sock_no_mmap
};
static int
base_sock_create(struct net *net, struct socket *sock, int protocol, int kern)
{
struct sock *sk;
if (sock->type != SOCK_RAW)
return -ESOCKTNOSUPPORT;
sk = sk_alloc(net, PF_ISDN, GFP_KERNEL, &mISDN_proto, kern);
if (!sk)
return -ENOMEM;
sock_init_data(sock, sk);
sock->ops = &base_sock_ops;
sock->state = SS_UNCONNECTED;
sock_reset_flag(sk, SOCK_ZAPPED);
sk->sk_protocol = protocol;
sk->sk_state = MISDN_OPEN;
mISDN_sock_link(&base_sockets, sk);
return 0;
}
static int
mISDN_sock_create(struct net *net, struct socket *sock, int proto, int kern)
{
int err = -EPROTONOSUPPORT;
switch (proto) {
case ISDN_P_BASE:
err = base_sock_create(net, sock, proto, kern);
break;
case ISDN_P_TE_S0:
case ISDN_P_NT_S0:
case ISDN_P_TE_E1:
case ISDN_P_NT_E1:
case ISDN_P_LAPD_TE:
case ISDN_P_LAPD_NT:
case ISDN_P_B_RAW:
case ISDN_P_B_HDLC:
case ISDN_P_B_X75SLP:
case ISDN_P_B_L2DTMF:
case ISDN_P_B_L2DSP:
case ISDN_P_B_L2DSPHDLC:
err = data_sock_create(net, sock, proto, kern);
break;
default:
return err;
}
return err;
}
static const struct net_proto_family mISDN_sock_family_ops = {
.owner = THIS_MODULE,
.family = PF_ISDN,
.create = mISDN_sock_create,
};
int
misdn_sock_init(u_int *deb)
{
int err;
debug = deb;
err = sock_register(&mISDN_sock_family_ops);
if (err)
printk(KERN_ERR "%s: error(%d)\n", __func__, err);
return err;
}
void
misdn_sock_cleanup(void)
{
sock_unregister(PF_ISDN);
}