1/*
2 * Generic HDLC support routines for Linux
3 * HDLC support
4 *
5 * Copyright (C) 1999 - 2006 Krzysztof Halasa <khc@pm.waw.pl>
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of version 2 of the GNU General Public License
9 * as published by the Free Software Foundation.
10 */
11
12#include <linux/module.h>
13#include <linux/kernel.h>
14#include <linux/slab.h>
15#include <linux/poll.h>
16#include <linux/errno.h>
17#include <linux/if_arp.h>
18#include <linux/init.h>
19#include <linux/skbuff.h>
20#include <linux/pkt_sched.h>
21#include <linux/inetdevice.h>
22#include <linux/lapb.h>
23#include <linux/rtnetlink.h>
24#include <linux/hdlc.h>
25
26
27static int raw_ioctl(struct net_device *dev, struct ifreq *ifr);
28
29static __be16 raw_type_trans(struct sk_buff *skb, struct net_device *dev)
30{
31	return __constant_htons(ETH_P_IP);
32}
33
34
35
36static struct hdlc_proto proto = {
37	.type_trans	= raw_type_trans,
38	.ioctl		= raw_ioctl,
39	.module		= THIS_MODULE,
40};
41
42
43static int raw_ioctl(struct net_device *dev, struct ifreq *ifr)
44{
45	raw_hdlc_proto __user *raw_s = ifr->ifr_settings.ifs_ifsu.raw_hdlc;
46	const size_t size = sizeof(raw_hdlc_proto);
47	raw_hdlc_proto new_settings;
48	hdlc_device *hdlc = dev_to_hdlc(dev);
49	int result;
50
51	switch (ifr->ifr_settings.type) {
52	case IF_GET_PROTO:
53		if (dev_to_hdlc(dev)->proto != &proto)
54			return -EINVAL;
55		ifr->ifr_settings.type = IF_PROTO_HDLC;
56		if (ifr->ifr_settings.size < size) {
57			ifr->ifr_settings.size = size; /* data size wanted */
58			return -ENOBUFS;
59		}
60		if (copy_to_user(raw_s, hdlc->state, size))
61			return -EFAULT;
62		return 0;
63
64	case IF_PROTO_HDLC:
65		if (!capable(CAP_NET_ADMIN))
66			return -EPERM;
67
68		if (dev->flags & IFF_UP)
69			return -EBUSY;
70
71		if (copy_from_user(&new_settings, raw_s, size))
72			return -EFAULT;
73
74		if (new_settings.encoding == ENCODING_DEFAULT)
75			new_settings.encoding = ENCODING_NRZ;
76
77		if (new_settings.parity == PARITY_DEFAULT)
78			new_settings.parity = PARITY_CRC16_PR1_CCITT;
79
80		result = hdlc->attach(dev, new_settings.encoding,
81				      new_settings.parity);
82		if (result)
83			return result;
84
85		result = attach_hdlc_protocol(dev, &proto, NULL,
86					      sizeof(raw_hdlc_proto));
87		if (result)
88			return result;
89		memcpy(hdlc->state, &new_settings, size);
90		dev->hard_start_xmit = hdlc->xmit;
91		dev->type = ARPHRD_RAWHDLC;
92		netif_dormant_off(dev);
93		return 0;
94	}
95
96	return -EINVAL;
97}
98
99
100static int __init mod_init(void)
101{
102	register_hdlc_protocol(&proto);
103	return 0;
104}
105
106
107
108static void __exit mod_exit(void)
109{
110	unregister_hdlc_protocol(&proto);
111}
112
113
114module_init(mod_init);
115module_exit(mod_exit);
116
117MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
118MODULE_DESCRIPTION("Raw HDLC protocol support for generic HDLC");
119MODULE_LICENSE("GPL v2");
120