linux/drivers/net/pppox.c
Eric W. Biederman 1b8d7ae42d [NET]: Make socket creation namespace safe.
This patch passes in the namespace a new socket should be created in
and has the socket code do the appropriate reference counting.  By
virtue of this all socket create methods are touched.  In addition
the socket create methods are modified so that they will fail if
you attempt to create a socket in a non-default network namespace.

Failing if we attempt to create a socket outside of the default
network namespace ensures that as we incrementally make the network stack
network namespace aware we will not export functionality that someone
has not audited and made certain is network namespace safe.
Allowing us to partially enable network namespaces before all of the
exotic protocols are supported.

Any protocol layers I have missed will fail to compile because I now
pass an extra parameter into the socket creation code.

[ Integrated AF_IUCV build fixes from Andrew Morton... -DaveM ]

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:49:07 -07:00

158 lines
3.4 KiB
C

/** -*- linux-c -*- ***********************************************************
* Linux PPP over X/Ethernet (PPPoX/PPPoE) Sockets
*
* PPPoX --- Generic PPP encapsulation socket family
* PPPoE --- PPP over Ethernet (RFC 2516)
*
*
* Version: 0.5.2
*
* Author: Michal Ostrowski <mostrows@speakeasy.net>
*
* 051000 : Initialization cleanup
*
* License:
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
*/
#include <linux/string.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/errno.h>
#include <linux/netdevice.h>
#include <linux/net.h>
#include <linux/init.h>
#include <linux/if_pppox.h>
#include <linux/ppp_defs.h>
#include <linux/if_ppp.h>
#include <linux/ppp_channel.h>
#include <linux/kmod.h>
#include <net/sock.h>
#include <asm/uaccess.h>
static struct pppox_proto *pppox_protos[PX_MAX_PROTO + 1];
int register_pppox_proto(int proto_num, struct pppox_proto *pp)
{
if (proto_num < 0 || proto_num > PX_MAX_PROTO)
return -EINVAL;
if (pppox_protos[proto_num])
return -EALREADY;
pppox_protos[proto_num] = pp;
return 0;
}
void unregister_pppox_proto(int proto_num)
{
if (proto_num >= 0 && proto_num <= PX_MAX_PROTO)
pppox_protos[proto_num] = NULL;
}
void pppox_unbind_sock(struct sock *sk)
{
/* Clear connection to ppp device, if attached. */
if (sk->sk_state & (PPPOX_BOUND | PPPOX_CONNECTED | PPPOX_ZOMBIE)) {
ppp_unregister_channel(&pppox_sk(sk)->chan);
sk->sk_state = PPPOX_DEAD;
}
}
EXPORT_SYMBOL(register_pppox_proto);
EXPORT_SYMBOL(unregister_pppox_proto);
EXPORT_SYMBOL(pppox_unbind_sock);
int pppox_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
{
struct sock *sk = sock->sk;
struct pppox_sock *po = pppox_sk(sk);
int rc;
lock_sock(sk);
switch (cmd) {
case PPPIOCGCHAN: {
int index;
rc = -ENOTCONN;
if (!(sk->sk_state & PPPOX_CONNECTED))
break;
rc = -EINVAL;
index = ppp_channel_index(&po->chan);
if (put_user(index , (int __user *) arg))
break;
rc = 0;
sk->sk_state |= PPPOX_BOUND;
break;
}
default:
rc = pppox_protos[sk->sk_protocol]->ioctl ?
pppox_protos[sk->sk_protocol]->ioctl(sock, cmd, arg) : -ENOTTY;
}
release_sock(sk);
return rc;
}
EXPORT_SYMBOL(pppox_ioctl);
static int pppox_create(struct net *net, struct socket *sock, int protocol)
{
int rc = -EPROTOTYPE;
if (net != &init_net)
return -EAFNOSUPPORT;
if (protocol < 0 || protocol > PX_MAX_PROTO)
goto out;
rc = -EPROTONOSUPPORT;
#ifdef CONFIG_KMOD
if (!pppox_protos[protocol]) {
char buffer[32];
sprintf(buffer, "pppox-proto-%d", protocol);
request_module(buffer);
}
#endif
if (!pppox_protos[protocol] ||
!try_module_get(pppox_protos[protocol]->owner))
goto out;
rc = pppox_protos[protocol]->create(net, sock);
module_put(pppox_protos[protocol]->owner);
out:
return rc;
}
static struct net_proto_family pppox_proto_family = {
.family = PF_PPPOX,
.create = pppox_create,
.owner = THIS_MODULE,
};
static int __init pppox_init(void)
{
return sock_register(&pppox_proto_family);
}
static void __exit pppox_exit(void)
{
sock_unregister(PF_PPPOX);
}
module_init(pppox_init);
module_exit(pppox_exit);
MODULE_AUTHOR("Michal Ostrowski <mostrows@speakeasy.net>");
MODULE_DESCRIPTION("PPP over Ethernet driver (generic socket layer)");
MODULE_LICENSE("GPL");