aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/net/wan/hdlc_ppp.c
blob: 3caeb528eacea2f247820a6e2f65e181c54f9e2e (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
/*
 * Generic HDLC support routines for Linux
 * Point-to-point protocol support
 *
 * Copyright (C) 1999 - 2006 Krzysztof Halasa <khc@pm.waw.pl>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of version 2 of the GNU General Public License
 * as published by the Free Software Foundation.
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/poll.h>
#include <linux/errno.h>
#include <linux/if_arp.h>
#include <linux/init.h>
#include <linux/skbuff.h>
#include <linux/pkt_sched.h>
#include <linux/inetdevice.h>
#include <linux/lapb.h>
#include <linux/rtnetlink.h>
#include <linux/hdlc.h>
#include <net/syncppp.h>

struct ppp_state {
	struct ppp_device pppdev;
	struct ppp_device *syncppp_ptr;
	int (*old_change_mtu)(struct net_device *dev, int new_mtu);
};

static int ppp_ioctl(struct net_device *dev, struct ifreq *ifr);


static inline struct ppp_state* state(hdlc_device *hdlc)
{
	return(struct ppp_state *)(hdlc->state);
}


static int ppp_open(struct net_device *dev)
{
	hdlc_device *hdlc = dev_to_hdlc(dev);
	void *old_ioctl;
	int result;

	dev->priv = &state(hdlc)->syncppp_ptr;
	state(hdlc)->syncppp_ptr = &state(hdlc)->pppdev;
	state(hdlc)->pppdev.dev = dev;

	old_ioctl = dev->do_ioctl;
	state(hdlc)->old_change_mtu = dev->change_mtu;
	sppp_attach(&state(hdlc)->pppdev);
	/* sppp_attach nukes them. We don't need syncppp's ioctl */
	dev->do_ioctl = old_ioctl;
	state(hdlc)->pppdev.sppp.pp_flags &= ~PP_CISCO;
	dev->type = ARPHRD_PPP;
	result = sppp_open(dev);
	if (result) {
		sppp_detach(dev);
		return result;
	}

	return 0;
}



static void ppp_close(struct net_device *dev)
{
	hdlc_device *hdlc = dev_to_hdlc(dev);

	sppp_close(dev);
	sppp_detach(dev);

	dev->change_mtu = state(hdlc)->old_change_mtu;
	dev->mtu = HDLC_MAX_MTU;
	dev->hard_header_len = 16;
}



static __be16 ppp_type_trans(struct sk_buff *skb, struct net_device *dev)
{
	return __constant_htons(ETH_P_WAN_PPP);
}



static struct hdlc_proto proto = {
	.open		= ppp_open,
	.close		= ppp_close,
	.type_trans	= ppp_type_trans,
	.ioctl		= ppp_ioctl,
	.module		= THIS_MODULE,
};


static int ppp_ioctl(struct net_device *dev, struct ifreq *ifr)
{
	hdlc_device *hdlc = dev_to_hdlc(dev);
	int result;

	switch (ifr->ifr_settings.type) {
	case IF_GET_PROTO:
		if (dev_to_hdlc(dev)->proto != &proto)
			return -EINVAL;
		ifr->ifr_settings.type = IF_PROTO_PPP;
		return 0; /* return protocol only, no settable parameters */

	case IF_PROTO_PPP:
		if(!capable(CAP_NET_ADMIN))
			return -EPERM;

		if(dev->flags & IFF_UP)
			return -EBUSY;

		/* no settable parameters */

		result=hdlc->attach(dev, ENCODING_NRZ,PARITY_CRC16_PR1_CCITT);
		if (result)
			return result;

		result = attach_hdlc_protocol(dev, &proto, NULL,
					      sizeof(struct ppp_state));
		if (result)
			return result;
		dev->hard_start_xmit = hdlc->xmit;
		dev->type = ARPHRD_PPP;
		netif_dormant_off(dev);
		return 0;
	}

	return -EINVAL;
}


static int __init mod_init(void)
{
	register_hdlc_protocol(&proto);
	return 0;
}



static void __exit mod_exit(void)
{
	unregister_hdlc_protocol(&proto);
}


module_init(mod_init);
module_exit(mod_exit);

MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
MODULE_DESCRIPTION("PPP protocol support for generic HDLC");
MODULE_LICENSE("GPL v2");