tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Generic HDLC support routines for Linux
3 * X.25 support
4 *
5 * Copyright (C) 1999 - 2003 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#include <net/x25device.h>
27
28/* These functions are callbacks called by LAPB layer */
29
30static void x25_connect_disconnect(struct net_device *dev, int reason, int code)
31{
32 struct sk_buff *skb;
33 unsigned char *ptr;
34
35 if ((skb = dev_alloc_skb(1)) == NULL) {
36 printk(KERN_ERR "%s: out of memory\n", dev->name);
37 return;
38 }
39
40 ptr = skb_put(skb, 1);
41 *ptr = code;
42
43 skb->protocol = x25_type_trans(skb, dev);
44 netif_rx(skb);
45}
46
47
48
49static void x25_connected(struct net_device *dev, int reason)
50{
51 x25_connect_disconnect(dev, reason, 1);
52}
53
54
55
56static void x25_disconnected(struct net_device *dev, int reason)
57{
58 x25_connect_disconnect(dev, reason, 2);
59}
60
61
62
63static int x25_data_indication(struct net_device *dev, struct sk_buff *skb)
64{
65 unsigned char *ptr;
66
67 skb_push(skb, 1);
68
69 if (skb_cow(skb, 1))
70 return NET_RX_DROP;
71
72 ptr = skb->data;
73 *ptr = 0;
74
75 skb->protocol = x25_type_trans(skb, dev);
76 return netif_rx(skb);
77}
78
79
80
81static void x25_data_transmit(struct net_device *dev, struct sk_buff *skb)
82{
83 hdlc_device *hdlc = dev_to_hdlc(dev);
84 hdlc->xmit(skb, dev); /* Ignore return value :-( */
85}
86
87
88
89static int x25_xmit(struct sk_buff *skb, struct net_device *dev)
90{
91 int result;
92
93
94 /* X.25 to LAPB */
95 switch (skb->data[0]) {
96 case 0: /* Data to be transmitted */
97 skb_pull(skb, 1);
98 if ((result = lapb_data_request(dev, skb)) != LAPB_OK)
99 dev_kfree_skb(skb);
100 return 0;
101
102 case 1:
103 if ((result = lapb_connect_request(dev))!= LAPB_OK) {
104 if (result == LAPB_CONNECTED)
105 /* Send connect confirm. msg to level 3 */
106 x25_connected(dev, 0);
107 else
108 printk(KERN_ERR "%s: LAPB connect request "
109 "failed, error code = %i\n",
110 dev->name, result);
111 }
112 break;
113
114 case 2:
115 if ((result = lapb_disconnect_request(dev)) != LAPB_OK) {
116 if (result == LAPB_NOTCONNECTED)
117 /* Send disconnect confirm. msg to level 3 */
118 x25_disconnected(dev, 0);
119 else
120 printk(KERN_ERR "%s: LAPB disconnect request "
121 "failed, error code = %i\n",
122 dev->name, result);
123 }
124 break;
125
126 default: /* to be defined */
127 break;
128 }
129
130 dev_kfree_skb(skb);
131 return 0;
132}
133
134
135
136static int x25_open(struct net_device *dev)
137{
138 struct lapb_register_struct cb;
139 int result;
140
141 cb.connect_confirmation = x25_connected;
142 cb.connect_indication = x25_connected;
143 cb.disconnect_confirmation = x25_disconnected;
144 cb.disconnect_indication = x25_disconnected;
145 cb.data_indication = x25_data_indication;
146 cb.data_transmit = x25_data_transmit;
147
148 result = lapb_register(dev, &cb);
149 if (result != LAPB_OK)
150 return result;
151 return 0;
152}
153
154
155
156static void x25_close(struct net_device *dev)
157{
158 lapb_unregister(dev);
159}
160
161
162
163static int x25_rx(struct sk_buff *skb)
164{
165 hdlc_device *hdlc = dev_to_hdlc(skb->dev);
166
167 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL) {
168 hdlc->stats.rx_dropped++;
169 return NET_RX_DROP;
170 }
171
172 if (lapb_data_received(skb->dev, skb) == LAPB_OK)
173 return NET_RX_SUCCESS;
174
175 hdlc->stats.rx_errors++;
176 dev_kfree_skb_any(skb);
177 return NET_RX_DROP;
178}
179
180
181
182int hdlc_x25_ioctl(struct net_device *dev, struct ifreq *ifr)
183{
184 hdlc_device *hdlc = dev_to_hdlc(dev);
185 int result;
186
187 switch (ifr->ifr_settings.type) {
188 case IF_GET_PROTO:
189 ifr->ifr_settings.type = IF_PROTO_X25;
190 return 0; /* return protocol only, no settable parameters */
191
192 case IF_PROTO_X25:
193 if(!capable(CAP_NET_ADMIN))
194 return -EPERM;
195
196 if(dev->flags & IFF_UP)
197 return -EBUSY;
198
199 result=hdlc->attach(dev, ENCODING_NRZ,PARITY_CRC16_PR1_CCITT);
200 if (result)
201 return result;
202
203 hdlc_proto_detach(hdlc);
204 memset(&hdlc->proto, 0, sizeof(hdlc->proto));
205
206 hdlc->proto.open = x25_open;
207 hdlc->proto.close = x25_close;
208 hdlc->proto.netif_rx = x25_rx;
209 hdlc->proto.type_trans = NULL;
210 hdlc->proto.id = IF_PROTO_X25;
211 dev->hard_start_xmit = x25_xmit;
212 dev->hard_header = NULL;
213 dev->type = ARPHRD_X25;
214 dev->addr_len = 0;
215 return 0;
216 }
217
218 return -EINVAL;
219}