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 #include <linux/errno.h>
24 #include <linux/types.h>
25 #include <linux/socket.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>
35 #include <asm/system.h>
36 #include <asm/uaccess.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>
46 #include <net/x25device.h>
48 static char bcast_addr
[6] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
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
55 struct list_head node
;
56 struct net_device
*ethdev
; /* link to ethernet device */
57 struct net_device
*axdev
; /* lapbeth device (lapb#) */
60 static LIST_HEAD(lapbeth_devices
);
62 /* ------------------------------------------------------------------------ */
65 * Get the LAPB device for the ethernet device
67 static struct lapbethdev
*lapbeth_get_x25_dev(struct net_device
*dev
)
69 struct lapbethdev
*lapbeth
;
71 list_for_each_entry_rcu(lapbeth
, &lapbeth_devices
, node
) {
72 if (lapbeth
->ethdev
== dev
)
78 static __inline__
int dev_is_ethdev(struct net_device
*dev
)
80 return dev
->type
== ARPHRD_ETHER
&& strncmp(dev
->name
, "dummy", 5);
83 /* ------------------------------------------------------------------------ */
86 * Receive a LAPB frame via an ethernet interface.
88 static int lapbeth_rcv(struct sk_buff
*skb
, struct net_device
*dev
, struct packet_type
*ptype
, struct net_device
*orig_dev
)
91 struct lapbethdev
*lapbeth
;
93 if (dev_net(dev
) != &init_net
)
96 if ((skb
= skb_share_check(skb
, GFP_ATOMIC
)) == NULL
)
99 if (!pskb_may_pull(skb
, 2))
103 lapbeth
= lapbeth_get_x25_dev(dev
);
106 if (!netif_running(lapbeth
->axdev
))
109 len
= skb
->data
[0] + skb
->data
[1] * 256;
110 dev
->stats
.rx_packets
++;
111 dev
->stats
.rx_bytes
+= len
;
113 skb_pull(skb
, 2); /* Remove the length bytes */
114 skb_trim(skb
, len
); /* Set the length of the data */
116 if ((err
= lapb_data_received(lapbeth
->axdev
, skb
)) != LAPB_OK
) {
117 printk(KERN_DEBUG
"lapbether: lapb_data_received err - %d\n", err
);
131 static int lapbeth_data_indication(struct net_device
*dev
, struct sk_buff
*skb
)
143 skb
->protocol
= x25_type_trans(skb
, dev
);
144 return netif_rx(skb
);
148 * Send a LAPB frame via an ethernet interface
150 static int lapbeth_xmit(struct sk_buff
*skb
, struct net_device
*dev
)
155 * Just to be *really* sure not to send anything if the interface
156 * is down, the ethernet device may have gone.
158 if (!netif_running(dev
)) {
162 switch (skb
->data
[0]) {
167 if ((err
= lapb_connect_request(dev
)) != LAPB_OK
)
168 printk(KERN_ERR
"lapbeth: lapb_connect_request "
172 if ((err
= lapb_disconnect_request(dev
)) != LAPB_OK
)
173 printk(KERN_ERR
"lapbeth: lapb_disconnect_request "
182 if ((err
= lapb_data_request(dev
, skb
)) != LAPB_OK
) {
183 printk(KERN_ERR
"lapbeth: lapb_data_request error - %d\n", err
);
197 static void lapbeth_data_transmit(struct net_device
*ndev
, struct sk_buff
*skb
)
199 struct lapbethdev
*lapbeth
= netdev_priv(ndev
);
201 struct net_device
*dev
;
204 skb
->protocol
= htons(ETH_P_X25
);
206 ptr
= skb_push(skb
, 2);
211 ndev
->stats
.tx_packets
++;
212 ndev
->stats
.tx_bytes
+= size
;
214 skb
->dev
= dev
= lapbeth
->ethdev
;
216 dev_hard_header(skb
, dev
, ETH_P_DEC
, bcast_addr
, NULL
, 0);
221 static void lapbeth_connected(struct net_device
*dev
, int reason
)
224 struct sk_buff
*skb
= dev_alloc_skb(1);
227 printk(KERN_ERR
"lapbeth: out of memory\n");
231 ptr
= skb_put(skb
, 1);
234 skb
->protocol
= x25_type_trans(skb
, dev
);
238 static void lapbeth_disconnected(struct net_device
*dev
, int reason
)
241 struct sk_buff
*skb
= dev_alloc_skb(1);
244 printk(KERN_ERR
"lapbeth: out of memory\n");
248 ptr
= skb_put(skb
, 1);
251 skb
->protocol
= x25_type_trans(skb
, dev
);
258 static int lapbeth_set_mac_address(struct net_device
*dev
, void *addr
)
260 struct sockaddr
*sa
= addr
;
261 memcpy(dev
->dev_addr
, sa
->sa_data
, dev
->addr_len
);
266 static struct lapb_register_struct lapbeth_callbacks
= {
267 .connect_confirmation
= lapbeth_connected
,
268 .connect_indication
= lapbeth_connected
,
269 .disconnect_confirmation
= lapbeth_disconnected
,
270 .disconnect_indication
= lapbeth_disconnected
,
271 .data_indication
= lapbeth_data_indication
,
272 .data_transmit
= lapbeth_data_transmit
,
277 * open/close a device
279 static int lapbeth_open(struct net_device
*dev
)
283 if ((err
= lapb_register(dev
, &lapbeth_callbacks
)) != LAPB_OK
) {
284 printk(KERN_ERR
"lapbeth: lapb_register error - %d\n", err
);
288 netif_start_queue(dev
);
292 static int lapbeth_close(struct net_device
*dev
)
296 netif_stop_queue(dev
);
298 if ((err
= lapb_unregister(dev
)) != LAPB_OK
)
299 printk(KERN_ERR
"lapbeth: lapb_unregister error - %d\n", err
);
304 /* ------------------------------------------------------------------------ */
306 static void lapbeth_setup(struct net_device
*dev
)
308 dev
->hard_start_xmit
= lapbeth_xmit
;
309 dev
->open
= lapbeth_open
;
310 dev
->stop
= lapbeth_close
;
311 dev
->destructor
= free_netdev
;
312 dev
->set_mac_address
= lapbeth_set_mac_address
;
313 dev
->type
= ARPHRD_X25
;
314 dev
->hard_header_len
= 3;
320 * Setup a new device.
322 static int lapbeth_new_device(struct net_device
*dev
)
324 struct net_device
*ndev
;
325 struct lapbethdev
*lapbeth
;
330 ndev
= alloc_netdev(sizeof(*lapbeth
), "lapb%d",
335 lapbeth
= netdev_priv(ndev
);
336 lapbeth
->axdev
= ndev
;
339 lapbeth
->ethdev
= dev
;
341 rc
= dev_alloc_name(ndev
, ndev
->name
);
346 if (register_netdevice(ndev
))
349 list_add_rcu(&lapbeth
->node
, &lapbeth_devices
);
361 * Free a lapb network device.
363 static void lapbeth_free_device(struct lapbethdev
*lapbeth
)
365 dev_put(lapbeth
->ethdev
);
366 list_del_rcu(&lapbeth
->node
);
367 unregister_netdevice(lapbeth
->axdev
);
371 * Handle device status changes.
373 * Called from notifier with RTNL held.
375 static int lapbeth_device_event(struct notifier_block
*this,
376 unsigned long event
, void *ptr
)
378 struct lapbethdev
*lapbeth
;
379 struct net_device
*dev
= ptr
;
381 if (dev_net(dev
) != &init_net
)
384 if (!dev_is_ethdev(dev
))
389 /* New ethernet device -> new LAPB interface */
390 if (lapbeth_get_x25_dev(dev
) == NULL
)
391 lapbeth_new_device(dev
);
394 /* ethernet device closed -> close LAPB interface */
395 lapbeth
= lapbeth_get_x25_dev(dev
);
397 dev_close(lapbeth
->axdev
);
399 case NETDEV_UNREGISTER
:
400 /* ethernet device disappears -> remove LAPB interface */
401 lapbeth
= lapbeth_get_x25_dev(dev
);
403 lapbeth_free_device(lapbeth
);
410 /* ------------------------------------------------------------------------ */
412 static struct packet_type lapbeth_packet_type __read_mostly
= {
413 .type
= cpu_to_be16(ETH_P_DEC
),
417 static struct notifier_block lapbeth_dev_notifier
= {
418 .notifier_call
= lapbeth_device_event
,
421 static const char banner
[] __initconst
=
422 KERN_INFO
"LAPB Ethernet driver version 0.02\n";
424 static int __init
lapbeth_init_driver(void)
426 dev_add_pack(&lapbeth_packet_type
);
428 register_netdevice_notifier(&lapbeth_dev_notifier
);
434 module_init(lapbeth_init_driver
);
436 static void __exit
lapbeth_cleanup_driver(void)
438 struct lapbethdev
*lapbeth
;
439 struct list_head
*entry
, *tmp
;
441 dev_remove_pack(&lapbeth_packet_type
);
442 unregister_netdevice_notifier(&lapbeth_dev_notifier
);
445 list_for_each_safe(entry
, tmp
, &lapbeth_devices
) {
446 lapbeth
= list_entry(entry
, struct lapbethdev
, node
);
448 dev_put(lapbeth
->ethdev
);
449 unregister_netdevice(lapbeth
->axdev
);
453 module_exit(lapbeth_cleanup_driver
);
455 MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
456 MODULE_DESCRIPTION("The unofficial LAPB over Ethernet driver");
457 MODULE_LICENSE("GPL");