96b232446c0b03533851be84da4b158e775f38a1
[linux-3.10.git] / drivers / net / wan / dlci.c
1 /*
2  * DLCI         Implementation of Frame Relay protocol for Linux, according to
3  *              RFC 1490.  This generic device provides en/decapsulation for an
4  *              underlying hardware driver.  Routes & IPs are assigned to these
5  *              interfaces.  Requires 'dlcicfg' program to create usable 
6  *              interfaces, the initial one, 'dlci' is for IOCTL use only.
7  *
8  * Version:     @(#)dlci.c      0.35    4 Jan 1997
9  *
10  * Author:      Mike McLagan <mike.mclagan@linux.org>
11  *
12  * Changes:
13  *
14  *              0.15    Mike Mclagan    Packet freeing, bug in kmalloc call
15  *                                      DLCI_RET handling
16  *              0.20    Mike McLagan    More conservative on which packets
17  *                                      are returned for retry and which are
18  *                                      are dropped.  If DLCI_RET_DROP is
19  *                                      returned from the FRAD, the packet is
20  *                                      sent back to Linux for re-transmission
21  *              0.25    Mike McLagan    Converted to use SIOC IOCTL calls
22  *              0.30    Jim Freeman     Fixed to allow IPX traffic
23  *              0.35    Michael Elizabeth       Fixed incorrect memcpy_fromfs
24  *
25  *              This program is free software; you can redistribute it and/or
26  *              modify it under the terms of the GNU General Public License
27  *              as published by the Free Software Foundation; either version
28  *              2 of the License, or (at your option) any later version.
29  */
30
31 #include <linux/module.h>
32 #include <linux/kernel.h>
33 #include <linux/types.h>
34 #include <linux/fcntl.h>
35 #include <linux/interrupt.h>
36 #include <linux/ptrace.h>
37 #include <linux/ioport.h>
38 #include <linux/in.h>
39 #include <linux/init.h>
40 #include <linux/slab.h>
41 #include <linux/string.h>
42 #include <linux/errno.h>
43 #include <linux/netdevice.h>
44 #include <linux/skbuff.h>
45 #include <linux/if_arp.h>
46 #include <linux/if_frad.h>
47 #include <linux/bitops.h>
48
49 #include <net/sock.h>
50
51 #include <asm/system.h>
52 #include <asm/io.h>
53 #include <asm/dma.h>
54 #include <asm/uaccess.h>
55
56 static const char version[] = "DLCI driver v0.35, 4 Jan 1997, mike.mclagan@linux.org";
57
58 static LIST_HEAD(dlci_devs);
59
60 static void dlci_setup(struct net_device *);
61
62 /* 
63  * these encapsulate the RFC 1490 requirements as well as 
64  * deal with packet transmission and reception, working with
65  * the upper network layers 
66  */
67
68 static int dlci_header(struct sk_buff *skb, struct net_device *dev, 
69                        unsigned short type, const void *daddr,
70                        const void *saddr, unsigned len)
71 {
72         struct frhdr            hdr;
73         struct dlci_local       *dlp;
74         unsigned int            hlen;
75         char                    *dest;
76
77         dlp = dev->priv;
78
79         hdr.control = FRAD_I_UI;
80         switch(type)
81         {
82                 case ETH_P_IP:
83                         hdr.IP_NLPID = FRAD_P_IP;
84                         hlen = sizeof(hdr.control) + sizeof(hdr.IP_NLPID);
85                         break;
86
87                 /* feel free to add other types, if necessary */
88
89                 default:
90                         hdr.pad = FRAD_P_PADDING;
91                         hdr.NLPID = FRAD_P_SNAP;
92                         memset(hdr.OUI, 0, sizeof(hdr.OUI));
93                         hdr.PID = htons(type);
94                         hlen = sizeof(hdr);
95                         break;
96         }
97
98         dest = skb_push(skb, hlen);
99         if (!dest)
100                 return(0);
101
102         memcpy(dest, &hdr, hlen);
103
104         return(hlen);
105 }
106
107 static void dlci_receive(struct sk_buff *skb, struct net_device *dev)
108 {
109         struct dlci_local *dlp;
110         struct frhdr            *hdr;
111         int                                     process, header;
112
113         dlp = dev->priv;
114         if (!pskb_may_pull(skb, sizeof(*hdr))) {
115                 printk(KERN_NOTICE "%s: invalid data no header\n",
116                        dev->name);
117                 dlp->stats.rx_errors++;
118                 kfree_skb(skb);
119                 return;
120         }
121
122         hdr = (struct frhdr *) skb->data;
123         process = 0;
124         header = 0;
125         skb->dev = dev;
126
127         if (hdr->control != FRAD_I_UI)
128         {
129                 printk(KERN_NOTICE "%s: Invalid header flag 0x%02X.\n", dev->name, hdr->control);
130                 dlp->stats.rx_errors++;
131         }
132         else
133                 switch(hdr->IP_NLPID)
134                 {
135                         case FRAD_P_PADDING:
136                                 if (hdr->NLPID != FRAD_P_SNAP)
137                                 {
138                                         printk(KERN_NOTICE "%s: Unsupported NLPID 0x%02X.\n", dev->name, hdr->NLPID);
139                                         dlp->stats.rx_errors++;
140                                         break;
141                                 }
142          
143                                 if (hdr->OUI[0] + hdr->OUI[1] + hdr->OUI[2] != 0)
144                                 {
145                                         printk(KERN_NOTICE "%s: Unsupported organizationally unique identifier 0x%02X-%02X-%02X.\n", dev->name, hdr->OUI[0], hdr->OUI[1], hdr->OUI[2]);
146                                         dlp->stats.rx_errors++;
147                                         break;
148                                 }
149
150                                 /* at this point, it's an EtherType frame */
151                                 header = sizeof(struct frhdr);
152                                 /* Already in network order ! */
153                                 skb->protocol = hdr->PID;
154                                 process = 1;
155                                 break;
156
157                         case FRAD_P_IP:
158                                 header = sizeof(hdr->control) + sizeof(hdr->IP_NLPID);
159                                 skb->protocol = htons(ETH_P_IP);
160                                 process = 1;
161                                 break;
162
163                         case FRAD_P_SNAP:
164                         case FRAD_P_Q933:
165                         case FRAD_P_CLNP:
166                                 printk(KERN_NOTICE "%s: Unsupported NLPID 0x%02X.\n", dev->name, hdr->pad);
167                                 dlp->stats.rx_errors++;
168                                 break;
169
170                         default:
171                                 printk(KERN_NOTICE "%s: Invalid pad byte 0x%02X.\n", dev->name, hdr->pad);
172                                 dlp->stats.rx_errors++;
173                                 break;                          
174                 }
175
176         if (process)
177         {
178                 /* we've set up the protocol, so discard the header */
179                 skb_reset_mac_header(skb);
180                 skb_pull(skb, header);
181                 dlp->stats.rx_bytes += skb->len;
182                 netif_rx(skb);
183                 dlp->stats.rx_packets++;
184                 dev->last_rx = jiffies;
185         }
186         else
187                 dev_kfree_skb(skb);
188 }
189
190 static int dlci_transmit(struct sk_buff *skb, struct net_device *dev)
191 {
192         struct dlci_local *dlp;
193         int                                     ret;
194
195         ret = 0;
196
197         if (!skb || !dev)
198                 return(0);
199
200         dlp = dev->priv;
201
202         netif_stop_queue(dev);
203         
204         ret = dlp->slave->hard_start_xmit(skb, dlp->slave);
205         switch (ret)
206         {
207                 case DLCI_RET_OK:
208                         dlp->stats.tx_packets++;
209                         ret = 0;
210                         break;
211                         case DLCI_RET_ERR:
212                         dlp->stats.tx_errors++;
213                         ret = 0;
214                         break;
215                         case DLCI_RET_DROP:
216                         dlp->stats.tx_dropped++;
217                         ret = 1;
218                         break;
219         }
220         /* Alan Cox recommends always returning 0, and always freeing the packet */
221         /* experience suggest a slightly more conservative approach */
222
223         if (!ret)
224         {
225                 dev_kfree_skb(skb);
226                 netif_wake_queue(dev);
227         }
228         return(ret);
229 }
230
231 static int dlci_config(struct net_device *dev, struct dlci_conf __user *conf, int get)
232 {
233         struct dlci_conf        config;
234         struct dlci_local       *dlp;
235         struct frad_local       *flp;
236         int                     err;
237
238         dlp = dev->priv;
239
240         flp = dlp->slave->priv;
241
242         if (!get)
243         {
244                 if(copy_from_user(&config, conf, sizeof(struct dlci_conf)))
245                         return -EFAULT;
246                 if (config.flags & ~DLCI_VALID_FLAGS)
247                         return(-EINVAL);
248                 memcpy(&dlp->config, &config, sizeof(struct dlci_conf));
249                 dlp->configured = 1;
250         }
251
252         err = (*flp->dlci_conf)(dlp->slave, dev, get);
253         if (err)
254                 return(err);
255
256         if (get)
257         {
258                 if(copy_to_user(conf, &dlp->config, sizeof(struct dlci_conf)))
259                         return -EFAULT;
260         }
261
262         return(0);
263 }
264
265 static int dlci_dev_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
266 {
267         struct dlci_local *dlp;
268
269         if (!capable(CAP_NET_ADMIN))
270                 return(-EPERM);
271
272         dlp = dev->priv;
273
274         switch(cmd)
275         {
276                 case DLCI_GET_SLAVE:
277                         if (!*(short *)(dev->dev_addr))
278                                 return(-EINVAL);
279
280                         strncpy(ifr->ifr_slave, dlp->slave->name, sizeof(ifr->ifr_slave));
281                         break;
282
283                 case DLCI_GET_CONF:
284                 case DLCI_SET_CONF:
285                         if (!*(short *)(dev->dev_addr))
286                                 return(-EINVAL);
287
288                         return(dlci_config(dev, ifr->ifr_data, cmd == DLCI_GET_CONF));
289                         break;
290
291                 default: 
292                         return(-EOPNOTSUPP);
293         }
294         return(0);
295 }
296
297 static int dlci_change_mtu(struct net_device *dev, int new_mtu)
298 {
299         struct dlci_local *dlp;
300
301         dlp = dev->priv;
302
303         return((*dlp->slave->change_mtu)(dlp->slave, new_mtu));
304 }
305
306 static int dlci_open(struct net_device *dev)
307 {
308         struct dlci_local       *dlp;
309         struct frad_local       *flp;
310         int                     err;
311
312         dlp = dev->priv;
313
314         if (!*(short *)(dev->dev_addr))
315                 return(-EINVAL);
316
317         if (!netif_running(dlp->slave))
318                 return(-ENOTCONN);
319
320         flp = dlp->slave->priv;
321         err = (*flp->activate)(dlp->slave, dev);
322         if (err)
323                 return(err);
324
325         netif_start_queue(dev);
326
327         return 0;
328 }
329
330 static int dlci_close(struct net_device *dev)
331 {
332         struct dlci_local       *dlp;
333         struct frad_local       *flp;
334         int                     err;
335
336         netif_stop_queue(dev);
337
338         dlp = dev->priv;
339
340         flp = dlp->slave->priv;
341         err = (*flp->deactivate)(dlp->slave, dev);
342
343         return 0;
344 }
345
346 static struct net_device_stats *dlci_get_stats(struct net_device *dev)
347 {
348         struct dlci_local *dlp;
349
350         dlp = dev->priv;
351
352         return(&dlp->stats);
353 }
354
355 static int dlci_add(struct dlci_add *dlci)
356 {
357         struct net_device       *master, *slave;
358         struct dlci_local       *dlp;
359         struct frad_local       *flp;
360         int                     err = -EINVAL;
361
362
363         /* validate slave device */
364         slave = dev_get_by_name(&init_net, dlci->devname);
365         if (!slave)
366                 return -ENODEV;
367
368         if (slave->type != ARPHRD_FRAD || slave->priv == NULL)
369                 goto err1;
370
371         /* create device name */
372         master = alloc_netdev( sizeof(struct dlci_local), "dlci%d",
373                               dlci_setup);
374         if (!master) {
375                 err = -ENOMEM;
376                 goto err1;
377         }
378
379         /* make sure same slave not already registered */
380         rtnl_lock();
381         list_for_each_entry(dlp, &dlci_devs, list) {
382                 if (dlp->slave == slave) {
383                         err = -EBUSY;
384                         goto err2;
385                 }
386         }
387
388         err = dev_alloc_name(master, master->name);
389         if (err < 0)
390                 goto err2;
391
392         *(short *)(master->dev_addr) = dlci->dlci;
393
394         dlp = (struct dlci_local *) master->priv;
395         dlp->slave = slave;
396         dlp->master = master;
397
398         flp = slave->priv;
399         err = (*flp->assoc)(slave, master);
400         if (err < 0)
401                 goto err2;
402
403         err = register_netdevice(master);
404         if (err < 0) 
405                 goto err2;
406
407         strcpy(dlci->devname, master->name);
408
409         list_add(&dlp->list, &dlci_devs);
410         rtnl_unlock();
411
412         return(0);
413
414  err2:
415         rtnl_unlock();
416         free_netdev(master);
417  err1:
418         dev_put(slave);
419         return(err);
420 }
421
422 static int dlci_del(struct dlci_add *dlci)
423 {
424         struct dlci_local       *dlp;
425         struct frad_local       *flp;
426         struct net_device       *master, *slave;
427         int                     err;
428
429         /* validate slave device */
430         master = __dev_get_by_name(&init_net, dlci->devname);
431         if (!master)
432                 return(-ENODEV);
433
434         if (netif_running(master)) {
435                 return(-EBUSY);
436         }
437
438         dlp = master->priv;
439         slave = dlp->slave;
440         flp = slave->priv;
441
442         rtnl_lock();
443         err = (*flp->deassoc)(slave, master);
444         if (!err) {
445                 list_del(&dlp->list);
446
447                 unregister_netdevice(master);
448
449                 dev_put(slave);
450         }
451         rtnl_unlock();
452
453         return(err);
454 }
455
456 static int dlci_ioctl(unsigned int cmd, void __user *arg)
457 {
458         struct dlci_add add;
459         int err;
460         
461         if (!capable(CAP_NET_ADMIN))
462                 return(-EPERM);
463
464         if(copy_from_user(&add, arg, sizeof(struct dlci_add)))
465                 return -EFAULT;
466
467         switch (cmd)
468         {
469                 case SIOCADDDLCI:
470                         err = dlci_add(&add);
471
472                         if (!err)
473                                 if(copy_to_user(arg, &add, sizeof(struct dlci_add)))
474                                         return -EFAULT;
475                         break;
476
477                 case SIOCDELDLCI:
478                         err = dlci_del(&add);
479                         break;
480
481                 default:
482                         err = -EINVAL;
483         }
484
485         return(err);
486 }
487
488 static const struct header_ops dlci_header_ops = {
489         .create = dlci_header,
490 };
491
492 static void dlci_setup(struct net_device *dev)
493 {
494         struct dlci_local *dlp = dev->priv;
495
496         dev->flags              = 0;
497         dev->open               = dlci_open;
498         dev->stop               = dlci_close;
499         dev->do_ioctl           = dlci_dev_ioctl;
500         dev->hard_start_xmit    = dlci_transmit;
501         dev->header_ops         = &dlci_header_ops;
502         dev->get_stats          = dlci_get_stats;
503         dev->change_mtu         = dlci_change_mtu;
504         dev->destructor         = free_netdev;
505
506         dlp->receive            = dlci_receive;
507
508         dev->type               = ARPHRD_DLCI;
509         dev->hard_header_len    = sizeof(struct frhdr);
510         dev->addr_len           = sizeof(short);
511
512 }
513
514 /* if slave is unregistering, then cleanup master */
515 static int dlci_dev_event(struct notifier_block *unused,
516                           unsigned long event, void *ptr)
517 {
518         struct net_device *dev = (struct net_device *) ptr;
519
520         if (dev->nd_net != &init_net)
521                 return NOTIFY_DONE;
522
523         if (event == NETDEV_UNREGISTER) {
524                 struct dlci_local *dlp;
525
526                 list_for_each_entry(dlp, &dlci_devs, list) {
527                         if (dlp->slave == dev) {
528                                 list_del(&dlp->list);
529                                 unregister_netdevice(dlp->master);
530                                 dev_put(dlp->slave);
531                                 break;
532                         }
533                 }
534         }
535         return NOTIFY_DONE;
536 }
537
538 static struct notifier_block dlci_notifier = {
539         .notifier_call = dlci_dev_event,
540 };
541
542 static int __init init_dlci(void)
543 {
544         dlci_ioctl_set(dlci_ioctl);
545         register_netdevice_notifier(&dlci_notifier);
546
547         printk("%s.\n", version);
548
549         return 0;
550 }
551
552 static void __exit dlci_exit(void)
553 {
554         struct dlci_local       *dlp, *nxt;
555         
556         dlci_ioctl_set(NULL);
557         unregister_netdevice_notifier(&dlci_notifier);
558
559         rtnl_lock();
560         list_for_each_entry_safe(dlp, nxt, &dlci_devs, list) {
561                 unregister_netdevice(dlp->master);
562                 dev_put(dlp->slave);
563         }
564         rtnl_unlock();
565 }
566
567 module_init(init_dlci);
568 module_exit(dlci_exit);
569
570 MODULE_AUTHOR("Mike McLagan");
571 MODULE_DESCRIPTION("Frame Relay DLCI layer");
572 MODULE_LICENSE("GPL");