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/slab.h>
26#include <linux/errno.h>
27#include <linux/netdevice.h>
28#include <linux/net.h>
29#include <linux/init.h>
30#include <linux/if_pppox.h>
31#include <linux/ppp_defs.h>
32#include <linux/if_ppp.h>
33#include <linux/ppp_channel.h>
34#include <linux/kmod.h>
35
36#include <net/sock.h>
37
38#include <asm/uaccess.h>
39
40static struct pppox_proto *pppox_protos[PX_MAX_PROTO + 1];
41
42int register_pppox_proto(int proto_num, struct pppox_proto *pp)
43{
44	if (proto_num < 0 || proto_num > PX_MAX_PROTO)
45		return -EINVAL;
46	if (pppox_protos[proto_num])
47		return -EALREADY;
48	pppox_protos[proto_num] = pp;
49	return 0;
50}
51
52void unregister_pppox_proto(int proto_num)
53{
54	if (proto_num >= 0 && proto_num <= PX_MAX_PROTO)
55		pppox_protos[proto_num] = NULL;
56}
57
58void pppox_unbind_sock(struct sock *sk)
59{
60	/* Clear connection to ppp device, if attached. */
61
62	if (sk->sk_state & (PPPOX_BOUND | PPPOX_CONNECTED | PPPOX_ZOMBIE)) {
63		ppp_unregister_channel(&pppox_sk(sk)->chan);
64		sk->sk_state = PPPOX_DEAD;
65	}
66}
67
68EXPORT_SYMBOL(register_pppox_proto);
69EXPORT_SYMBOL(unregister_pppox_proto);
70EXPORT_SYMBOL(pppox_unbind_sock);
71
72int pppox_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
73{
74	struct sock *sk = sock->sk;
75	struct pppox_sock *po = pppox_sk(sk);
76	int rc = 0;
77
78	lock_sock(sk);
79
80	switch (cmd) {
81	case PPPIOCGCHAN: {
82		int index;
83		rc = -ENOTCONN;
84		if (!(sk->sk_state & PPPOX_CONNECTED))
85			break;
86
87		rc = -EINVAL;
88		index = ppp_channel_index(&po->chan);
89		if (put_user(index , (int __user *) arg))
90			break;
91
92		rc = 0;
93		sk->sk_state |= PPPOX_BOUND;
94		break;
95	}
96	default:
97		if (pppox_protos[sk->sk_protocol]->ioctl)
98			rc = pppox_protos[sk->sk_protocol]->ioctl(sock, cmd,
99								  arg);
100
101		break;
102	};
103
104	release_sock(sk);
105	return rc;
106}
107
108EXPORT_SYMBOL(pppox_ioctl);
109
110static int pppox_create(struct socket *sock, int protocol)
111{
112	int rc = -EPROTOTYPE;
113
114	if (protocol < 0 || protocol > PX_MAX_PROTO)
115		goto out;
116
117	rc = -EPROTONOSUPPORT;
118#ifdef CONFIG_KMOD
119	if (!pppox_protos[protocol]) {
120		char buffer[32];
121		sprintf(buffer, "pppox-proto-%d", protocol);
122		request_module(buffer);
123	}
124#endif
125	if (!pppox_protos[protocol] ||
126	    !try_module_get(pppox_protos[protocol]->owner))
127		goto out;
128
129	rc = pppox_protos[protocol]->create(sock);
130
131	module_put(pppox_protos[protocol]->owner);
132out:
133	return rc;
134}
135
136static struct net_proto_family pppox_proto_family = {
137	.family	= PF_PPPOX,
138	.create	= pppox_create,
139	.owner	= THIS_MODULE,
140};
141
142static int __init pppox_init(void)
143{
144	return sock_register(&pppox_proto_family);
145}
146
147static void __exit pppox_exit(void)
148{
149	sock_unregister(PF_PPPOX);
150}
151
152module_init(pppox_init);
153module_exit(pppox_exit);
154
155MODULE_AUTHOR("Michal Ostrowski <mostrows@speakeasy.net>");
156MODULE_DESCRIPTION("PPP over Ethernet driver (generic socket layer)");
157MODULE_LICENSE("GPL");
158