tokenring: convert to netdev_tx_t
[linux-2.6-block.git] / drivers / net / wan / lapbether.c
CommitLineData
1da177e4
LT
1/*
2 * "LAPB via ethernet" driver release 001
3 *
4 * This code REQUIRES 2.1.15 or higher/ NET3.038
5 *
6 * This module:
7 * This module is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version
10 * 2 of the License, or (at your option) any later version.
11 *
12 * This is a "pseudo" network driver to allow LAPB over Ethernet.
13 *
14 * This driver can use any ethernet destination address, and can be
15 * limited to accept frames from one dedicated ethernet card only.
16 *
17 * History
18 * LAPBETH 001 Jonathan Naylor Cloned from bpqether.c
19 * 2000-10-29 Henner Eisen lapb_data_indication() return status.
20 * 2000-11-14 Henner Eisen dev_hold/put, NETDEV_GOING_DOWN support
21 */
22
23#include <linux/errno.h>
24#include <linux/types.h>
25#include <linux/socket.h>
26#include <linux/in.h>
27#include <linux/kernel.h>
28#include <linux/string.h>
29#include <linux/net.h>
30#include <linux/inet.h>
31#include <linux/netdevice.h>
32#include <linux/if_arp.h>
33#include <linux/skbuff.h>
34#include <net/sock.h>
35#include <asm/system.h>
36#include <asm/uaccess.h>
37#include <linux/mm.h>
38#include <linux/interrupt.h>
39#include <linux/notifier.h>
40#include <linux/stat.h>
41#include <linux/netfilter.h>
42#include <linux/module.h>
43#include <linux/lapb.h>
44#include <linux/init.h>
45
46#include <net/x25device.h>
47
48static char bcast_addr[6] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
49
50/* If this number is made larger, check that the temporary string buffer
51 * in lapbeth_new_device is large enough to store the probe device name.*/
52#define MAXLAPBDEV 100
53
54struct lapbethdev {
55 struct list_head node;
56 struct net_device *ethdev; /* link to ethernet device */
57 struct net_device *axdev; /* lapbeth device (lapb#) */
1da177e4
LT
58};
59
293a3839 60static LIST_HEAD(lapbeth_devices);
1da177e4
LT
61
62/* ------------------------------------------------------------------------ */
63
64/*
65 * Get the LAPB device for the ethernet device
66 */
67static struct lapbethdev *lapbeth_get_x25_dev(struct net_device *dev)
68{
69 struct lapbethdev *lapbeth;
70
71 list_for_each_entry_rcu(lapbeth, &lapbeth_devices, node) {
72 if (lapbeth->ethdev == dev)
73 return lapbeth;
74 }
75 return NULL;
76}
77
78static __inline__ int dev_is_ethdev(struct net_device *dev)
79{
80 return dev->type == ARPHRD_ETHER && strncmp(dev->name, "dummy", 5);
81}
82
83/* ------------------------------------------------------------------------ */
84
85/*
86 * Receive a LAPB frame via an ethernet interface.
87 */
f2ccd8fa 88static int lapbeth_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *ptype, struct net_device *orig_dev)
1da177e4
LT
89{
90 int len, err;
91 struct lapbethdev *lapbeth;
92
c346dca1 93 if (dev_net(dev) != &init_net)
e730c155
EB
94 goto drop;
95
1da177e4
LT
96 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
97 return NET_RX_DROP;
98
99 if (!pskb_may_pull(skb, 2))
100 goto drop;
101
102 rcu_read_lock();
103 lapbeth = lapbeth_get_x25_dev(dev);
104 if (!lapbeth)
105 goto drop_unlock;
106 if (!netif_running(lapbeth->axdev))
107 goto drop_unlock;
108
1da177e4 109 len = skb->data[0] + skb->data[1] * 256;
ea2ebaf8
SH
110 dev->stats.rx_packets++;
111 dev->stats.rx_bytes += len;
1da177e4
LT
112
113 skb_pull(skb, 2); /* Remove the length bytes */
114 skb_trim(skb, len); /* Set the length of the data */
115
116 if ((err = lapb_data_received(lapbeth->axdev, skb)) != LAPB_OK) {
117 printk(KERN_DEBUG "lapbether: lapb_data_received err - %d\n", err);
118 goto drop_unlock;
119 }
120out:
121 rcu_read_unlock();
122 return 0;
123drop_unlock:
124 kfree_skb(skb);
125 goto out;
126drop:
127 kfree_skb(skb);
128 return 0;
129}
130
131static int lapbeth_data_indication(struct net_device *dev, struct sk_buff *skb)
132{
133 unsigned char *ptr;
134
135 skb_push(skb, 1);
136
137 if (skb_cow(skb, 1))
138 return NET_RX_DROP;
139
140 ptr = skb->data;
141 *ptr = 0x00;
142
143 skb->protocol = x25_type_trans(skb, dev);
1da177e4
LT
144 return netif_rx(skb);
145}
146
147/*
148 * Send a LAPB frame via an ethernet interface
149 */
150static int lapbeth_xmit(struct sk_buff *skb, struct net_device *dev)
151{
d77eeb70 152 int err;
1da177e4
LT
153
154 /*
155 * Just to be *really* sure not to send anything if the interface
156 * is down, the ethernet device may have gone.
157 */
d77eeb70 158 if (!netif_running(dev))
1da177e4 159 goto drop;
1da177e4
LT
160
161 switch (skb->data[0]) {
162 case 0x00:
1da177e4
LT
163 break;
164 case 0x01:
165 if ((err = lapb_connect_request(dev)) != LAPB_OK)
166 printk(KERN_ERR "lapbeth: lapb_connect_request "
167 "error: %d\n", err);
d77eeb70 168 goto drop;
1da177e4
LT
169 case 0x02:
170 if ((err = lapb_disconnect_request(dev)) != LAPB_OK)
171 printk(KERN_ERR "lapbeth: lapb_disconnect_request "
172 "err: %d\n", err);
173 /* Fall thru */
174 default:
d77eeb70 175 goto drop;
1da177e4
LT
176 }
177
178 skb_pull(skb, 1);
179
180 if ((err = lapb_data_request(dev, skb)) != LAPB_OK) {
181 printk(KERN_ERR "lapbeth: lapb_data_request error - %d\n", err);
1da177e4
LT
182 goto drop;
183 }
1da177e4 184out:
d77eeb70 185 return NETDEV_TX_OK;
1da177e4
LT
186drop:
187 kfree_skb(skb);
188 goto out;
189}
190
191static void lapbeth_data_transmit(struct net_device *ndev, struct sk_buff *skb)
192{
193 struct lapbethdev *lapbeth = netdev_priv(ndev);
194 unsigned char *ptr;
195 struct net_device *dev;
196 int size = skb->len;
197
198 skb->protocol = htons(ETH_P_X25);
199
200 ptr = skb_push(skb, 2);
201
202 *ptr++ = size % 256;
203 *ptr++ = size / 256;
204
ea2ebaf8
SH
205 ndev->stats.tx_packets++;
206 ndev->stats.tx_bytes += size;
1da177e4
LT
207
208 skb->dev = dev = lapbeth->ethdev;
209
0c4e8581 210 dev_hard_header(skb, dev, ETH_P_DEC, bcast_addr, NULL, 0);
1da177e4
LT
211
212 dev_queue_xmit(skb);
213}
214
215static void lapbeth_connected(struct net_device *dev, int reason)
216{
217 unsigned char *ptr;
218 struct sk_buff *skb = dev_alloc_skb(1);
219
220 if (!skb) {
221 printk(KERN_ERR "lapbeth: out of memory\n");
222 return;
223 }
224
225 ptr = skb_put(skb, 1);
226 *ptr = 0x01;
227
228 skb->protocol = x25_type_trans(skb, dev);
1da177e4
LT
229 netif_rx(skb);
230}
231
232static void lapbeth_disconnected(struct net_device *dev, int reason)
233{
234 unsigned char *ptr;
235 struct sk_buff *skb = dev_alloc_skb(1);
236
237 if (!skb) {
238 printk(KERN_ERR "lapbeth: out of memory\n");
239 return;
240 }
241
242 ptr = skb_put(skb, 1);
243 *ptr = 0x02;
244
245 skb->protocol = x25_type_trans(skb, dev);
1da177e4
LT
246 netif_rx(skb);
247}
248
1da177e4
LT
249/*
250 * Set AX.25 callsign
251 */
252static int lapbeth_set_mac_address(struct net_device *dev, void *addr)
253{
254 struct sockaddr *sa = addr;
255 memcpy(dev->dev_addr, sa->sa_data, dev->addr_len);
256 return 0;
257}
258
259
260static struct lapb_register_struct lapbeth_callbacks = {
261 .connect_confirmation = lapbeth_connected,
262 .connect_indication = lapbeth_connected,
263 .disconnect_confirmation = lapbeth_disconnected,
264 .disconnect_indication = lapbeth_disconnected,
265 .data_indication = lapbeth_data_indication,
266 .data_transmit = lapbeth_data_transmit,
267
268};
269
270/*
271 * open/close a device
272 */
273static int lapbeth_open(struct net_device *dev)
274{
275 int err;
276
277 if ((err = lapb_register(dev, &lapbeth_callbacks)) != LAPB_OK) {
278 printk(KERN_ERR "lapbeth: lapb_register error - %d\n", err);
279 return -ENODEV;
280 }
281
282 netif_start_queue(dev);
283 return 0;
284}
285
286static int lapbeth_close(struct net_device *dev)
287{
288 int err;
289
290 netif_stop_queue(dev);
291
292 if ((err = lapb_unregister(dev)) != LAPB_OK)
293 printk(KERN_ERR "lapbeth: lapb_unregister error - %d\n", err);
294
295 return 0;
296}
297
298/* ------------------------------------------------------------------------ */
299
39549b1e
SH
300static const struct net_device_ops lapbeth_netdev_ops = {
301 .ndo_open = lapbeth_open,
302 .ndo_stop = lapbeth_close,
303 .ndo_start_xmit = lapbeth_xmit,
304 .ndo_set_mac_address = lapbeth_set_mac_address,
305};
306
1da177e4
LT
307static void lapbeth_setup(struct net_device *dev)
308{
39549b1e 309 dev->netdev_ops = &lapbeth_netdev_ops;
1da177e4 310 dev->destructor = free_netdev;
1da177e4
LT
311 dev->type = ARPHRD_X25;
312 dev->hard_header_len = 3;
313 dev->mtu = 1000;
314 dev->addr_len = 0;
1da177e4
LT
315}
316
317/*
318 * Setup a new device.
319 */
320static int lapbeth_new_device(struct net_device *dev)
321{
322 struct net_device *ndev;
323 struct lapbethdev *lapbeth;
324 int rc = -ENOMEM;
325
326 ASSERT_RTNL();
327
328 ndev = alloc_netdev(sizeof(*lapbeth), "lapb%d",
329 lapbeth_setup);
330 if (!ndev)
331 goto out;
332
333 lapbeth = netdev_priv(ndev);
334 lapbeth->axdev = ndev;
335
336 dev_hold(dev);
337 lapbeth->ethdev = dev;
338
339 rc = dev_alloc_name(ndev, ndev->name);
340 if (rc < 0)
341 goto fail;
342
343 rc = -EIO;
344 if (register_netdevice(ndev))
345 goto fail;
346
347 list_add_rcu(&lapbeth->node, &lapbeth_devices);
348 rc = 0;
349out:
350 return rc;
351fail:
352 dev_put(dev);
353 free_netdev(ndev);
354 kfree(lapbeth);
355 goto out;
356}
357
358/*
359 * Free a lapb network device.
360 */
361static void lapbeth_free_device(struct lapbethdev *lapbeth)
362{
363 dev_put(lapbeth->ethdev);
364 list_del_rcu(&lapbeth->node);
365 unregister_netdevice(lapbeth->axdev);
366}
367
368/*
369 * Handle device status changes.
370 *
371 * Called from notifier with RTNL held.
372 */
373static int lapbeth_device_event(struct notifier_block *this,
374 unsigned long event, void *ptr)
375{
376 struct lapbethdev *lapbeth;
377 struct net_device *dev = ptr;
378
c346dca1 379 if (dev_net(dev) != &init_net)
e9dc8653
EB
380 return NOTIFY_DONE;
381
1da177e4
LT
382 if (!dev_is_ethdev(dev))
383 return NOTIFY_DONE;
384
385 switch (event) {
386 case NETDEV_UP:
387 /* New ethernet device -> new LAPB interface */
388 if (lapbeth_get_x25_dev(dev) == NULL)
389 lapbeth_new_device(dev);
390 break;
391 case NETDEV_DOWN:
392 /* ethernet device closed -> close LAPB interface */
393 lapbeth = lapbeth_get_x25_dev(dev);
394 if (lapbeth)
395 dev_close(lapbeth->axdev);
396 break;
397 case NETDEV_UNREGISTER:
398 /* ethernet device disappears -> remove LAPB interface */
399 lapbeth = lapbeth_get_x25_dev(dev);
400 if (lapbeth)
401 lapbeth_free_device(lapbeth);
402 break;
403 }
404
405 return NOTIFY_DONE;
406}
407
408/* ------------------------------------------------------------------------ */
409
7546dd97 410static struct packet_type lapbeth_packet_type __read_mostly = {
09640e63 411 .type = cpu_to_be16(ETH_P_DEC),
1da177e4
LT
412 .func = lapbeth_rcv,
413};
414
415static struct notifier_block lapbeth_dev_notifier = {
416 .notifier_call = lapbeth_device_event,
417};
418
81b700b1 419static const char banner[] __initconst =
5ee0d593 420 KERN_INFO "LAPB Ethernet driver version 0.02\n";
1da177e4
LT
421
422static int __init lapbeth_init_driver(void)
423{
424 dev_add_pack(&lapbeth_packet_type);
425
426 register_netdevice_notifier(&lapbeth_dev_notifier);
427
428 printk(banner);
429
430 return 0;
431}
432module_init(lapbeth_init_driver);
433
434static void __exit lapbeth_cleanup_driver(void)
435{
436 struct lapbethdev *lapbeth;
437 struct list_head *entry, *tmp;
438
439 dev_remove_pack(&lapbeth_packet_type);
440 unregister_netdevice_notifier(&lapbeth_dev_notifier);
441
442 rtnl_lock();
443 list_for_each_safe(entry, tmp, &lapbeth_devices) {
444 lapbeth = list_entry(entry, struct lapbethdev, node);
445
e544ff00 446 dev_put(lapbeth->ethdev);
1da177e4
LT
447 unregister_netdevice(lapbeth->axdev);
448 }
449 rtnl_unlock();
450}
451module_exit(lapbeth_cleanup_driver);
452
453MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
454MODULE_DESCRIPTION("The unofficial LAPB over Ethernet driver");
455MODULE_LICENSE("GPL");