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
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
|
/*
* Generic HDLC support routines for Linux
* X.25 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/x25device.h>
static int x25_ioctl(struct net_device *dev, struct ifreq *ifr);
/* These functions are callbacks called by LAPB layer */
static void x25_connect_disconnect(struct net_device *dev, int reason, int code)
{
struct sk_buff *skb;
unsigned char *ptr;
if ((skb = dev_alloc_skb(1)) == NULL) {
printk(KERN_ERR "%s: out of memory\n", dev->name);
return;
}
ptr = skb_put(skb, 1);
*ptr = code;
skb->protocol = x25_type_trans(skb, dev);
netif_rx(skb);
}
static void x25_connected(struct net_device *dev, int reason)
{
x25_connect_disconnect(dev, reason, 1);
}
static void x25_disconnected(struct net_device *dev, int reason)
{
x25_connect_disconnect(dev, reason, 2);
}
static int x25_data_indication(struct net_device *dev, struct sk_buff *skb)
{
unsigned char *ptr;
skb_push(skb, 1);
if (skb_cow(skb, 1))
return NET_RX_DROP;
ptr = skb->data;
*ptr = 0;
skb->protocol = x25_type_trans(skb, dev);
return netif_rx(skb);
}
static void x25_data_transmit(struct net_device *dev, struct sk_buff *skb)
{
hdlc_device *hdlc = dev_to_hdlc(dev);
hdlc->xmit(skb, dev); /* Ignore return value :-( */
}
static int x25_xmit(struct sk_buff *skb, struct net_device *dev)
{
int result;
/* X.25 to LAPB */
switch (skb->data[0]) {
case 0: /* Data to be transmitted */
skb_pull(skb, 1);
if ((result = lapb_data_request(dev, skb)) != LAPB_OK)
dev_kfree_skb(skb);
return 0;
case 1:
if ((result = lapb_connect_request(dev))!= LAPB_OK) {
if (result == LAPB_CONNECTED)
/* Send connect confirm. msg to level 3 */
x25_connected(dev, 0);
else
printk(KERN_ERR "%s: LAPB connect request "
"failed, error code = %i\n",
dev->name, result);
}
break;
case 2:
if ((result = lapb_disconnect_request(dev)) != LAPB_OK) {
if (result == LAPB_NOTCONNECTED)
/* Send disconnect confirm. msg to level 3 */
x25_disconnected(dev, 0);
else
printk(KERN_ERR "%s: LAPB disconnect request "
"failed, error code = %i\n",
dev->name, result);
}
break;
default: /* to be defined */
break;
}
dev_kfree_skb(skb);
return 0;
}
static int x25_open(struct net_device *dev)
{
struct lapb_register_struct cb;
int result;
cb.connect_confirmation = x25_connected;
cb.connect_indication = x25_connected;
cb.disconnect_confirmation = x25_disconnected;
cb.disconnect_indication = x25_disconnected;
cb.data_indication = x25_data_indication;
cb.data_transmit = x25_data_transmit;
result = lapb_register(dev, &cb);
if (result != LAPB_OK)
return result;
return 0;
}
static void x25_close(struct net_device *dev)
{
lapb_unregister(dev);
}
static int x25_rx(struct sk_buff *skb)
{
struct hdlc_device_desc *desc = dev_to_desc(skb->dev);
if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL) {
desc->stats.rx_dropped++;
return NET_RX_DROP;
}
if (lapb_data_received(skb->dev, skb) == LAPB_OK)
return NET_RX_SUCCESS;
desc->stats.rx_errors++;
dev_kfree_skb_any(skb);
return NET_RX_DROP;
}
static struct hdlc_proto proto = {
.open = x25_open,
.close = x25_close,
.ioctl = x25_ioctl,
.module = THIS_MODULE,
};
static int x25_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_X25;
return 0; /* return protocol only, no settable parameters */
case IF_PROTO_X25:
if(!capable(CAP_NET_ADMIN))
return -EPERM;
if(dev->flags & IFF_UP)
return -EBUSY;
result=hdlc->attach(dev, ENCODING_NRZ,PARITY_CRC16_PR1_CCITT);
if (result)
return result;
if ((result = attach_hdlc_protocol(dev, &proto,
x25_rx, 0)) != 0)
return result;
dev->hard_start_xmit = x25_xmit;
dev->hard_header = NULL;
dev->type = ARPHRD_X25;
dev->addr_len = 0;
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("X.25 protocol support for generic HDLC");
MODULE_LICENSE("GPL v2");
|
