2 * "LAPB via ethernet" driver release 001
4 * This code REQUIRES 2.1.15 or higher/ NET3.038
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.
12 * This is a "pseudo" network driver to allow LAPB over Ethernet.
14 * This driver can use any ethernet destination address, and can be
15 * limited to accept frames from one dedicated ethernet card only.
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
23 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
25 #include <linux/errno.h>
26 #include <linux/types.h>
27 #include <linux/socket.h>
29 #include <linux/slab.h>
30 #include <linux/kernel.h>
31 #include <linux/string.h>
32 #include <linux/net.h>
33 #include <linux/inet.h>
34 #include <linux/netdevice.h>
35 #include <linux/if_arp.h>
36 #include <linux/skbuff.h>
38 #include <asm/system.h>
39 #include <asm/uaccess.h>
41 #include <linux/interrupt.h>
42 #include <linux/notifier.h>
43 #include <linux/stat.h>
44 #include <linux/netfilter.h>
45 #include <linux/module.h>
46 #include <linux/lapb.h>
47 #include <linux/init.h>
49 #include <net/x25device.h>
51 static const u8 bcast_addr[6] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
53 /* If this number is made larger, check that the temporary string buffer
54 * in lapbeth_new_device is large enough to store the probe device name.*/
55 #define MAXLAPBDEV 100
58 struct list_head node;
59 struct net_device *ethdev; /* link to ethernet device */
60 struct net_device *axdev; /* lapbeth device (lapb#) */
63 static LIST_HEAD(lapbeth_devices);
65 /* ------------------------------------------------------------------------ */
68 * Get the LAPB device for the ethernet device
70 static struct lapbethdev *lapbeth_get_x25_dev(struct net_device *dev)
72 struct lapbethdev *lapbeth;
74 list_for_each_entry_rcu(lapbeth, &lapbeth_devices, node) {
75 if (lapbeth->ethdev == dev)
81 static __inline__ int dev_is_ethdev(struct net_device *dev)
83 return dev->type == ARPHRD_ETHER && strncmp(dev->name, "dummy", 5);
86 /* ------------------------------------------------------------------------ */
89 * Receive a LAPB frame via an ethernet interface.
91 static int lapbeth_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *ptype, struct net_device *orig_dev)
94 struct lapbethdev *lapbeth;
96 if (dev_net(dev) != &init_net)
99 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
102 if (!pskb_may_pull(skb, 2))
106 lapbeth = lapbeth_get_x25_dev(dev);
109 if (!netif_running(lapbeth->axdev))
112 len = skb->data[0] + skb->data[1] * 256;
113 dev->stats.rx_packets++;
114 dev->stats.rx_bytes += len;
116 skb_pull(skb, 2); /* Remove the length bytes */
117 skb_trim(skb, len); /* Set the length of the data */
119 if ((err = lapb_data_received(lapbeth->axdev, skb)) != LAPB_OK) {
120 printk(KERN_DEBUG "lapbether: lapb_data_received err - %d\n", err);
134 static int lapbeth_data_indication(struct net_device *dev, struct sk_buff *skb)
144 *ptr = X25_IFACE_DATA;
146 skb->protocol = x25_type_trans(skb, dev);
147 return netif_rx(skb);
151 * Send a LAPB frame via an ethernet interface
153 static netdev_tx_t lapbeth_xmit(struct sk_buff *skb,
154 struct net_device *dev)
159 * Just to be *really* sure not to send anything if the interface
160 * is down, the ethernet device may have gone.
162 if (!netif_running(dev))
165 switch (skb->data[0]) {
168 case X25_IFACE_CONNECT:
169 if ((err = lapb_connect_request(dev)) != LAPB_OK)
170 pr_err("lapb_connect_request error: %d\n", err);
172 case X25_IFACE_DISCONNECT:
173 if ((err = lapb_disconnect_request(dev)) != LAPB_OK)
174 pr_err("lapb_disconnect_request err: %d\n", err);
182 if ((err = lapb_data_request(dev, skb)) != LAPB_OK) {
183 pr_err("lapb_data_request error - %d\n", err);
193 static void lapbeth_data_transmit(struct net_device *ndev, struct sk_buff *skb)
195 struct lapbethdev *lapbeth = netdev_priv(ndev);
197 struct net_device *dev;
200 skb->protocol = htons(ETH_P_X25);
202 ptr = skb_push(skb, 2);
207 ndev->stats.tx_packets++;
208 ndev->stats.tx_bytes += size;
210 skb->dev = dev = lapbeth->ethdev;
212 dev_hard_header(skb, dev, ETH_P_DEC, bcast_addr, NULL, 0);
217 static void lapbeth_connected(struct net_device *dev, int reason)
220 struct sk_buff *skb = dev_alloc_skb(1);
223 pr_err("out of memory\n");
227 ptr = skb_put(skb, 1);
228 *ptr = X25_IFACE_CONNECT;
230 skb->protocol = x25_type_trans(skb, dev);
234 static void lapbeth_disconnected(struct net_device *dev, int reason)
237 struct sk_buff *skb = dev_alloc_skb(1);
240 pr_err("out of memory\n");
244 ptr = skb_put(skb, 1);
245 *ptr = X25_IFACE_DISCONNECT;
247 skb->protocol = x25_type_trans(skb, dev);
254 static int lapbeth_set_mac_address(struct net_device *dev, void *addr)
256 struct sockaddr *sa = addr;
257 memcpy(dev->dev_addr, sa->sa_data, dev->addr_len);
262 static const struct lapb_register_struct lapbeth_callbacks = {
263 .connect_confirmation = lapbeth_connected,
264 .connect_indication = lapbeth_connected,
265 .disconnect_confirmation = lapbeth_disconnected,
266 .disconnect_indication = lapbeth_disconnected,
267 .data_indication = lapbeth_data_indication,
268 .data_transmit = lapbeth_data_transmit,
272 * open/close a device
274 static int lapbeth_open(struct net_device *dev)
278 if ((err = lapb_register(dev, &lapbeth_callbacks)) != LAPB_OK) {
279 pr_err("lapb_register error: %d\n", err);
283 netif_start_queue(dev);
287 static int lapbeth_close(struct net_device *dev)
291 netif_stop_queue(dev);
293 if ((err = lapb_unregister(dev)) != LAPB_OK)
294 pr_err("lapb_unregister error: %d\n", err);
299 /* ------------------------------------------------------------------------ */
301 static const struct net_device_ops lapbeth_netdev_ops = {
302 .ndo_open = lapbeth_open,
303 .ndo_stop = lapbeth_close,
304 .ndo_start_xmit = lapbeth_xmit,
305 .ndo_set_mac_address = lapbeth_set_mac_address,
308 static void lapbeth_setup(struct net_device *dev)
310 dev->netdev_ops = &lapbeth_netdev_ops;
311 dev->destructor = free_netdev;
312 dev->type = ARPHRD_X25;
313 dev->hard_header_len = 3;
319 * Setup a new device.
321 static int lapbeth_new_device(struct net_device *dev)
323 struct net_device *ndev;
324 struct lapbethdev *lapbeth;
329 ndev = alloc_netdev(sizeof(*lapbeth), "lapb%d",
334 lapbeth = netdev_priv(ndev);
335 lapbeth->axdev = ndev;
338 lapbeth->ethdev = dev;
341 if (register_netdevice(ndev))
344 list_add_rcu(&lapbeth->node, &lapbeth_devices);
356 * Free a lapb network device.
358 static void lapbeth_free_device(struct lapbethdev *lapbeth)
360 dev_put(lapbeth->ethdev);
361 list_del_rcu(&lapbeth->node);
362 unregister_netdevice(lapbeth->axdev);
366 * Handle device status changes.
368 * Called from notifier with RTNL held.
370 static int lapbeth_device_event(struct notifier_block *this,
371 unsigned long event, void *ptr)
373 struct lapbethdev *lapbeth;
374 struct net_device *dev = ptr;
376 if (dev_net(dev) != &init_net)
379 if (!dev_is_ethdev(dev))
384 /* New ethernet device -> new LAPB interface */
385 if (lapbeth_get_x25_dev(dev) == NULL)
386 lapbeth_new_device(dev);
389 /* ethernet device closed -> close LAPB interface */
390 lapbeth = lapbeth_get_x25_dev(dev);
392 dev_close(lapbeth->axdev);
394 case NETDEV_UNREGISTER:
395 /* ethernet device disappears -> remove LAPB interface */
396 lapbeth = lapbeth_get_x25_dev(dev);
398 lapbeth_free_device(lapbeth);
405 /* ------------------------------------------------------------------------ */
407 static struct packet_type lapbeth_packet_type __read_mostly = {
408 .type = cpu_to_be16(ETH_P_DEC),
412 static struct notifier_block lapbeth_dev_notifier = {
413 .notifier_call = lapbeth_device_event,
416 static const char banner[] __initconst =
417 KERN_INFO "LAPB Ethernet driver version 0.02\n";
419 static int __init lapbeth_init_driver(void)
421 dev_add_pack(&lapbeth_packet_type);
423 register_netdevice_notifier(&lapbeth_dev_notifier);
429 module_init(lapbeth_init_driver);
431 static void __exit lapbeth_cleanup_driver(void)
433 struct lapbethdev *lapbeth;
434 struct list_head *entry, *tmp;
436 dev_remove_pack(&lapbeth_packet_type);
437 unregister_netdevice_notifier(&lapbeth_dev_notifier);
440 list_for_each_safe(entry, tmp, &lapbeth_devices) {
441 lapbeth = list_entry(entry, struct lapbethdev, node);
443 dev_put(lapbeth->ethdev);
444 unregister_netdevice(lapbeth->axdev);
448 module_exit(lapbeth_cleanup_driver);
450 MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
451 MODULE_DESCRIPTION("The unofficial LAPB over Ethernet driver");
452 MODULE_LICENSE("GPL");