1/** -*- linux-c -*- ***********************************************************
  2 * Linux PPP over X/Ethernet (PPPoX/PPPoE) Sockets
  3 *
  4 * PPPoX --- Generic PPP encapsulation socket family
  5 * PPPoE --- PPP over Ethernet (RFC 2516)
  6 *
  7 *
  8 * Version:	0.5.2
  9 *
 10 * Author:	Michal Ostrowski <mostrows@speakeasy.net>
 11 *
 12 * 051000 :	Initialization cleanup
 13 *
 14 * License:
 15 *		This program is free software; you can redistribute it and/or
 16 *		modify it under the terms of the GNU General Public License
 17 *		as published by the Free Software Foundation; either version
 18 *		2 of the License, or (at your option) any later version.
 19 *
 20 */
 21
 22#include <linux/string.h>
 23#include <linux/module.h>
 24#include <linux/kernel.h>
 25#include <linux/errno.h>
 26#include <linux/netdevice.h>
 27#include <linux/net.h>
 28#include <linux/init.h>
 29#include <linux/if_pppox.h>
 30#include <linux/ppp_defs.h>
 31#include <linux/if_ppp.h>
 32#include <linux/ppp_channel.h>
 33#include <linux/kmod.h>
 34
 35#include <net/sock.h>
 36
 37#include <asm/uaccess.h>
 38
 39static const struct pppox_proto *pppox_protos[PX_MAX_PROTO + 1];
 40
 41int register_pppox_proto(int proto_num, const struct pppox_proto *pp)
 42{
 43	if (proto_num < 0 || proto_num > PX_MAX_PROTO)
 44		return -EINVAL;
 45	if (pppox_protos[proto_num])
 46		return -EALREADY;
 47	pppox_protos[proto_num] = pp;
 48	return 0;
 49}
 50
 51void unregister_pppox_proto(int proto_num)
 52{
 53	if (proto_num >= 0 && proto_num <= PX_MAX_PROTO)
 54		pppox_protos[proto_num] = NULL;
 55}
 56
 57void pppox_unbind_sock(struct sock *sk)
 58{
 59	/* Clear connection to ppp device, if attached. */
 60
 61	if (sk->sk_state & (PPPOX_BOUND | PPPOX_CONNECTED | PPPOX_ZOMBIE)) {
 62		ppp_unregister_channel(&pppox_sk(sk)->chan);
 63		sk->sk_state = PPPOX_DEAD;
 64	}
 65}
 66
 67EXPORT_SYMBOL(register_pppox_proto);
 68EXPORT_SYMBOL(unregister_pppox_proto);
 69EXPORT_SYMBOL(pppox_unbind_sock);
 70
 71int pppox_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 72{
 73	struct sock *sk = sock->sk;
 74	struct pppox_sock *po = pppox_sk(sk);
 75	int rc;
 76
 77	lock_sock(sk);
 78
 79	switch (cmd) {
 80	case PPPIOCGCHAN: {
 81		int index;
 82		rc = -ENOTCONN;
 83		if (!(sk->sk_state & PPPOX_CONNECTED))
 84			break;
 85
 86		rc = -EINVAL;
 87		index = ppp_channel_index(&po->chan);
 88		if (put_user(index , (int __user *) arg))
 89			break;
 90
 91		rc = 0;
 92		sk->sk_state |= PPPOX_BOUND;
 93		break;
 94	}
 95	default:
 96		rc = pppox_protos[sk->sk_protocol]->ioctl ?
 97			pppox_protos[sk->sk_protocol]->ioctl(sock, cmd, arg) : -ENOTTY;
 98	}
 99
100	release_sock(sk);
101	return rc;
102}
103
104EXPORT_SYMBOL(pppox_ioctl);
105
106static int pppox_create(struct net *net, struct socket *sock, int protocol,
107			int kern)
108{
109	int rc = -EPROTOTYPE;
110
111	if (protocol < 0 || protocol > PX_MAX_PROTO)
112		goto out;
113
114	rc = -EPROTONOSUPPORT;
115	if (!pppox_protos[protocol])
116		request_module("pppox-proto-%d", protocol);
117	if (!pppox_protos[protocol] ||
118	    !try_module_get(pppox_protos[protocol]->owner))
119		goto out;
120
121	rc = pppox_protos[protocol]->create(net, sock);
122
123	module_put(pppox_protos[protocol]->owner);
124out:
125	return rc;
126}
127
128static const struct net_proto_family pppox_proto_family = {
129	.family	= PF_PPPOX,
130	.create	= pppox_create,
131	.owner	= THIS_MODULE,
132};
133
134static int __init pppox_init(void)
135{
136	return sock_register(&pppox_proto_family);
137}
138
139static void __exit pppox_exit(void)
140{
141	sock_unregister(PF_PPPOX);
142}
143
144module_init(pppox_init);
145module_exit(pppox_exit);
146
147MODULE_AUTHOR("Michal Ostrowski <mostrows@speakeasy.net>");
148MODULE_DESCRIPTION("PPP over Ethernet driver (generic socket layer)");
149MODULE_LICENSE("GPL");