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57#include <linux/errno.h>
58#include <linux/types.h>
59#include <linux/socket.h>
60#include <linux/in.h>
61#include <linux/kernel.h>
62#include <linux/string.h>
63#include <linux/net.h>
64#include <linux/slab.h>
65#include <net/ax25.h>
66#include <linux/inet.h>
67#include <linux/netdevice.h>
68#include <linux/etherdevice.h>
69#include <linux/if_arp.h>
70#include <linux/skbuff.h>
71#include <net/sock.h>
72#include <linux/uaccess.h>
73#include <linux/mm.h>
74#include <linux/interrupt.h>
75#include <linux/notifier.h>
76#include <linux/proc_fs.h>
77#include <linux/seq_file.h>
78#include <linux/stat.h>
79#include <linux/module.h>
80#include <linux/init.h>
81#include <linux/rtnetlink.h>
82
83#include <net/ip.h>
84#include <net/arp.h>
85#include <net/net_namespace.h>
86
87#include <linux/bpqether.h>
88
89static const char banner[] __initconst = KERN_INFO \
90 "AX.25: bpqether driver version 004\n";
91
92static int bpq_rcv(struct sk_buff *, struct net_device *, struct packet_type *, struct net_device *);
93static int bpq_device_event(struct notifier_block *, unsigned long, void *);
94
95static struct packet_type bpq_packet_type __read_mostly = {
96 .type = cpu_to_be16(ETH_P_BPQ),
97 .func = bpq_rcv,
98};
99
100static struct notifier_block bpq_dev_notifier = {
101 .notifier_call = bpq_device_event,
102};
103
104
105struct bpqdev {
106 struct list_head bpq_list;
107 struct net_device *ethdev;
108 struct net_device *axdev;
109 char dest_addr[6];
110 char acpt_addr[6];
111};
112
113static LIST_HEAD(bpq_devices);
114
115
116
117
118
119
120static struct lock_class_key bpq_netdev_xmit_lock_key;
121static struct lock_class_key bpq_netdev_addr_lock_key;
122
123static void bpq_set_lockdep_class_one(struct net_device *dev,
124 struct netdev_queue *txq,
125 void *_unused)
126{
127 lockdep_set_class(&txq->_xmit_lock, &bpq_netdev_xmit_lock_key);
128}
129
130static void bpq_set_lockdep_class(struct net_device *dev)
131{
132 lockdep_set_class(&dev->addr_list_lock, &bpq_netdev_addr_lock_key);
133 netdev_for_each_tx_queue(dev, bpq_set_lockdep_class_one, NULL);
134}
135
136
137
138
139
140
141
142static inline struct net_device *bpq_get_ether_dev(struct net_device *dev)
143{
144 struct bpqdev *bpq = netdev_priv(dev);
145
146 return bpq ? bpq->ethdev : NULL;
147}
148
149
150
151
152static inline struct net_device *bpq_get_ax25_dev(struct net_device *dev)
153{
154 struct bpqdev *bpq;
155
156 list_for_each_entry_rcu(bpq, &bpq_devices, bpq_list) {
157 if (bpq->ethdev == dev)
158 return bpq->axdev;
159 }
160 return NULL;
161}
162
163static inline int dev_is_ethdev(struct net_device *dev)
164{
165 return dev->type == ARPHRD_ETHER && strncmp(dev->name, "dummy", 5);
166}
167
168
169
170
171
172
173
174static int bpq_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *ptype, struct net_device *orig_dev)
175{
176 int len;
177 char * ptr;
178 struct ethhdr *eth;
179 struct bpqdev *bpq;
180
181 if (!net_eq(dev_net(dev), &init_net))
182 goto drop;
183
184 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
185 return NET_RX_DROP;
186
187 if (!pskb_may_pull(skb, sizeof(struct ethhdr)))
188 goto drop;
189
190 rcu_read_lock();
191 dev = bpq_get_ax25_dev(dev);
192
193 if (dev == NULL || !netif_running(dev))
194 goto drop_unlock;
195
196
197
198
199
200
201 bpq = netdev_priv(dev);
202
203 eth = eth_hdr(skb);
204
205 if (!(bpq->acpt_addr[0] & 0x01) &&
206 !ether_addr_equal(eth->h_source, bpq->acpt_addr))
207 goto drop_unlock;
208
209 if (skb_cow(skb, sizeof(struct ethhdr)))
210 goto drop_unlock;
211
212 len = skb->data[0] + skb->data[1] * 256 - 5;
213
214 skb_pull(skb, 2);
215 skb_trim(skb, len);
216
217 dev->stats.rx_packets++;
218 dev->stats.rx_bytes += len;
219
220 ptr = skb_push(skb, 1);
221 *ptr = 0;
222
223 skb->protocol = ax25_type_trans(skb, dev);
224 netif_rx(skb);
225unlock:
226
227 rcu_read_unlock();
228
229 return 0;
230drop_unlock:
231 kfree_skb(skb);
232 goto unlock;
233
234drop:
235 kfree_skb(skb);
236 return 0;
237}
238
239
240
241
242static netdev_tx_t bpq_xmit(struct sk_buff *skb, struct net_device *dev)
243{
244 unsigned char *ptr;
245 struct bpqdev *bpq;
246 struct net_device *orig_dev;
247 int size;
248
249 if (skb->protocol == htons(ETH_P_IP))
250 return ax25_ip_xmit(skb);
251
252
253
254
255
256 if (!netif_running(dev)) {
257 kfree_skb(skb);
258 return NETDEV_TX_OK;
259 }
260
261 skb_pull(skb, 1);
262 size = skb->len;
263
264
265
266
267
268
269 if (skb_cow(skb, AX25_BPQ_HEADER_LEN)) {
270 if (net_ratelimit())
271 pr_err("bpqether: out of memory\n");
272 kfree_skb(skb);
273
274 return NETDEV_TX_OK;
275 }
276
277 ptr = skb_push(skb, 2);
278
279 *ptr++ = (size + 5) % 256;
280 *ptr++ = (size + 5) / 256;
281
282 bpq = netdev_priv(dev);
283
284 orig_dev = dev;
285 if ((dev = bpq_get_ether_dev(dev)) == NULL) {
286 orig_dev->stats.tx_dropped++;
287 kfree_skb(skb);
288 return NETDEV_TX_OK;
289 }
290
291 skb->protocol = ax25_type_trans(skb, dev);
292 skb_reset_network_header(skb);
293 dev_hard_header(skb, dev, ETH_P_BPQ, bpq->dest_addr, NULL, 0);
294 dev->stats.tx_packets++;
295 dev->stats.tx_bytes+=skb->len;
296
297 dev_queue_xmit(skb);
298 netif_wake_queue(dev);
299 return NETDEV_TX_OK;
300}
301
302
303
304
305static int bpq_set_mac_address(struct net_device *dev, void *addr)
306{
307 struct sockaddr *sa = (struct sockaddr *)addr;
308
309 memcpy(dev->dev_addr, sa->sa_data, dev->addr_len);
310
311 return 0;
312}
313
314
315
316
317
318
319
320
321static int bpq_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
322{
323 struct bpq_ethaddr __user *ethaddr = ifr->ifr_data;
324 struct bpqdev *bpq = netdev_priv(dev);
325 struct bpq_req req;
326
327 if (!capable(CAP_NET_ADMIN))
328 return -EPERM;
329
330 switch (cmd) {
331 case SIOCSBPQETHOPT:
332 if (copy_from_user(&req, ifr->ifr_data, sizeof(struct bpq_req)))
333 return -EFAULT;
334 switch (req.cmd) {
335 case SIOCGBPQETHPARAM:
336 case SIOCSBPQETHPARAM:
337 default:
338 return -EINVAL;
339 }
340
341 break;
342
343 case SIOCSBPQETHADDR:
344 if (copy_from_user(bpq->dest_addr, ethaddr->destination, ETH_ALEN))
345 return -EFAULT;
346 if (copy_from_user(bpq->acpt_addr, ethaddr->accept, ETH_ALEN))
347 return -EFAULT;
348 break;
349
350 default:
351 return -EINVAL;
352 }
353
354 return 0;
355}
356
357
358
359
360static int bpq_open(struct net_device *dev)
361{
362 netif_start_queue(dev);
363 return 0;
364}
365
366static int bpq_close(struct net_device *dev)
367{
368 netif_stop_queue(dev);
369 return 0;
370}
371
372
373
374
375
376
377
378
379static void *bpq_seq_start(struct seq_file *seq, loff_t *pos)
380 __acquires(RCU)
381{
382 int i = 1;
383 struct bpqdev *bpqdev;
384
385 rcu_read_lock();
386
387 if (*pos == 0)
388 return SEQ_START_TOKEN;
389
390 list_for_each_entry_rcu(bpqdev, &bpq_devices, bpq_list) {
391 if (i == *pos)
392 return bpqdev;
393 }
394 return NULL;
395}
396
397static void *bpq_seq_next(struct seq_file *seq, void *v, loff_t *pos)
398{
399 struct list_head *p;
400 struct bpqdev *bpqdev = v;
401
402 ++*pos;
403
404 if (v == SEQ_START_TOKEN)
405 p = rcu_dereference(list_next_rcu(&bpq_devices));
406 else
407 p = rcu_dereference(list_next_rcu(&bpqdev->bpq_list));
408
409 return (p == &bpq_devices) ? NULL
410 : list_entry(p, struct bpqdev, bpq_list);
411}
412
413static void bpq_seq_stop(struct seq_file *seq, void *v)
414 __releases(RCU)
415{
416 rcu_read_unlock();
417}
418
419
420static int bpq_seq_show(struct seq_file *seq, void *v)
421{
422 if (v == SEQ_START_TOKEN)
423 seq_puts(seq,
424 "dev ether destination accept from\n");
425 else {
426 const struct bpqdev *bpqdev = v;
427
428 seq_printf(seq, "%-5s %-10s %pM ",
429 bpqdev->axdev->name, bpqdev->ethdev->name,
430 bpqdev->dest_addr);
431
432 if (is_multicast_ether_addr(bpqdev->acpt_addr))
433 seq_printf(seq, "*\n");
434 else
435 seq_printf(seq, "%pM\n", bpqdev->acpt_addr);
436
437 }
438 return 0;
439}
440
441static const struct seq_operations bpq_seqops = {
442 .start = bpq_seq_start,
443 .next = bpq_seq_next,
444 .stop = bpq_seq_stop,
445 .show = bpq_seq_show,
446};
447
448
449
450static const struct net_device_ops bpq_netdev_ops = {
451 .ndo_open = bpq_open,
452 .ndo_stop = bpq_close,
453 .ndo_start_xmit = bpq_xmit,
454 .ndo_set_mac_address = bpq_set_mac_address,
455 .ndo_do_ioctl = bpq_ioctl,
456};
457
458static void bpq_setup(struct net_device *dev)
459{
460 dev->netdev_ops = &bpq_netdev_ops;
461 dev->needs_free_netdev = true;
462
463 memcpy(dev->broadcast, &ax25_bcast, AX25_ADDR_LEN);
464 memcpy(dev->dev_addr, &ax25_defaddr, AX25_ADDR_LEN);
465
466 dev->flags = 0;
467 dev->features = NETIF_F_LLTX;
468
469#if IS_ENABLED(CONFIG_AX25)
470 dev->header_ops = &ax25_header_ops;
471#endif
472
473 dev->type = ARPHRD_AX25;
474 dev->hard_header_len = AX25_MAX_HEADER_LEN + AX25_BPQ_HEADER_LEN;
475 dev->mtu = AX25_DEF_PACLEN;
476 dev->addr_len = AX25_ADDR_LEN;
477
478}
479
480
481
482
483static int bpq_new_device(struct net_device *edev)
484{
485 int err;
486 struct net_device *ndev;
487 struct bpqdev *bpq;
488
489 ndev = alloc_netdev(sizeof(struct bpqdev), "bpq%d", NET_NAME_UNKNOWN,
490 bpq_setup);
491 if (!ndev)
492 return -ENOMEM;
493
494
495 bpq = netdev_priv(ndev);
496 dev_hold(edev);
497 bpq->ethdev = edev;
498 bpq->axdev = ndev;
499
500 eth_broadcast_addr(bpq->dest_addr);
501 eth_broadcast_addr(bpq->acpt_addr);
502
503 err = register_netdevice(ndev);
504 if (err)
505 goto error;
506 bpq_set_lockdep_class(ndev);
507
508
509 list_add_rcu(&bpq->bpq_list, &bpq_devices);
510 return 0;
511
512 error:
513 dev_put(edev);
514 free_netdev(ndev);
515 return err;
516
517}
518
519static void bpq_free_device(struct net_device *ndev)
520{
521 struct bpqdev *bpq = netdev_priv(ndev);
522
523 dev_put(bpq->ethdev);
524 list_del_rcu(&bpq->bpq_list);
525
526 unregister_netdevice(ndev);
527}
528
529
530
531
532static int bpq_device_event(struct notifier_block *this,
533 unsigned long event, void *ptr)
534{
535 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
536
537 if (!net_eq(dev_net(dev), &init_net))
538 return NOTIFY_DONE;
539
540 if (!dev_is_ethdev(dev))
541 return NOTIFY_DONE;
542
543 switch (event) {
544 case NETDEV_UP:
545 if (bpq_get_ax25_dev(dev) == NULL)
546 bpq_new_device(dev);
547 break;
548
549 case NETDEV_DOWN:
550 if ((dev = bpq_get_ax25_dev(dev)) != NULL)
551 dev_close(dev);
552 break;
553
554 case NETDEV_UNREGISTER:
555 if ((dev = bpq_get_ax25_dev(dev)) != NULL)
556 bpq_free_device(dev);
557 break;
558 default:
559 break;
560 }
561
562 return NOTIFY_DONE;
563}
564
565
566
567
568
569
570
571
572static int __init bpq_init_driver(void)
573{
574#ifdef CONFIG_PROC_FS
575 if (!proc_create_seq("bpqether", 0444, init_net.proc_net, &bpq_seqops)) {
576 printk(KERN_ERR
577 "bpq: cannot create /proc/net/bpqether entry.\n");
578 return -ENOENT;
579 }
580#endif
581
582 dev_add_pack(&bpq_packet_type);
583
584 register_netdevice_notifier(&bpq_dev_notifier);
585
586 printk(banner);
587
588 return 0;
589}
590
591static void __exit bpq_cleanup_driver(void)
592{
593 struct bpqdev *bpq;
594
595 dev_remove_pack(&bpq_packet_type);
596
597 unregister_netdevice_notifier(&bpq_dev_notifier);
598
599 remove_proc_entry("bpqether", init_net.proc_net);
600
601 rtnl_lock();
602 while (!list_empty(&bpq_devices)) {
603 bpq = list_entry(bpq_devices.next, struct bpqdev, bpq_list);
604 bpq_free_device(bpq->axdev);
605 }
606 rtnl_unlock();
607}
608
609MODULE_AUTHOR("Joerg Reuter DL1BKE <jreuter@yaina.de>");
610MODULE_DESCRIPTION("Transmit and receive AX.25 packets over Ethernet");
611MODULE_LICENSE("GPL");
612module_init(bpq_init_driver);
613module_exit(bpq_cleanup_driver);
614