1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * slip.c This module implements the SLIP protocol for kernel-based |
4 | * devices like TTY. It interfaces between a raw TTY, and the |
5 | * kernel's INET protocol layers. |
6 | * |
7 | * Version: @(#)slip.c 0.8.3 12/24/94 |
8 | * |
9 | * Authors: Laurence Culhane, <loz@holmes.demon.co.uk> |
10 | * Fred N. van Kempen, <waltje@uwalt.nl.mugnet.org> |
11 | * |
12 | * Fixes: |
13 | * Alan Cox : Sanity checks and avoid tx overruns. |
14 | * Has a new sl->mtu field. |
15 | * Alan Cox : Found cause of overrun. ifconfig sl0 |
16 | * mtu upwards. Driver now spots this |
17 | * and grows/shrinks its buffers(hack!). |
18 | * Memory leak if you run out of memory |
19 | * setting up a slip driver fixed. |
20 | * Matt Dillon : Printable slip (borrowed from NET2E) |
21 | * Pauline Middelink : Slip driver fixes. |
22 | * Alan Cox : Honours the old SL_COMPRESSED flag |
23 | * Alan Cox : KISS AX.25 and AXUI IP support |
24 | * Michael Riepe : Automatic CSLIP recognition added |
25 | * Charles Hedrick : CSLIP header length problem fix. |
26 | * Alan Cox : Corrected non-IP cases of the above. |
27 | * Alan Cox : Now uses hardware type as per FvK. |
28 | * Alan Cox : Default to 192.168.0.0 (RFC 1597) |
29 | * A.N.Kuznetsov : dev_tint() recursion fix. |
30 | * Dmitry Gorodchanin : SLIP memory leaks |
31 | * Dmitry Gorodchanin : Code cleanup. Reduce tty driver |
32 | * buffering from 4096 to 256 bytes. |
33 | * Improving SLIP response time. |
34 | * CONFIG_SLIP_MODE_SLIP6. |
35 | * ifconfig sl? up & down now works |
36 | * correctly. |
37 | * Modularization. |
38 | * Alan Cox : Oops - fix AX.25 buffer lengths |
39 | * Dmitry Gorodchanin : Even more cleanups. Preserve CSLIP |
40 | * statistics. Include CSLIP code only |
41 | * if it really needed. |
42 | * Alan Cox : Free slhc buffers in the right place. |
43 | * Alan Cox : Allow for digipeated IP over AX.25 |
44 | * Matti Aarnio : Dynamic SLIP devices, with ideas taken |
45 | * from Jim Freeman's <jfree@caldera.com> |
46 | * dynamic PPP devices. We do NOT kfree() |
47 | * device entries, just reg./unreg. them |
48 | * as they are needed. We kfree() them |
49 | * at module cleanup. |
50 | * With MODULE-loading ``insmod'', user |
51 | * can issue parameter: slip_maxdev=1024 |
52 | * (Or how much he/she wants.. Default |
53 | * is 256) |
54 | * Stanislav Voronyi : Slip line checking, with ideas taken |
55 | * from multislip BSDI driver which was |
56 | * written by Igor Chechik, RELCOM Corp. |
57 | * Only algorithms have been ported to |
58 | * Linux SLIP driver. |
59 | * Vitaly E. Lavrov : Sane behaviour on tty hangup. |
60 | * Alexey Kuznetsov : Cleanup interfaces to tty & netdevice |
61 | * modules. |
62 | */ |
63 | |
64 | #define SL_CHECK_TRANSMIT |
65 | #include <linux/compat.h> |
66 | #include <linux/module.h> |
67 | #include <linux/moduleparam.h> |
68 | |
69 | #include <linux/uaccess.h> |
70 | #include <linux/bitops.h> |
71 | #include <linux/sched/signal.h> |
72 | #include <linux/string.h> |
73 | #include <linux/mm.h> |
74 | #include <linux/interrupt.h> |
75 | #include <linux/in.h> |
76 | #include <linux/tty.h> |
77 | #include <linux/errno.h> |
78 | #include <linux/netdevice.h> |
79 | #include <linux/etherdevice.h> |
80 | #include <linux/skbuff.h> |
81 | #include <linux/rtnetlink.h> |
82 | #include <linux/if_arp.h> |
83 | #include <linux/if_slip.h> |
84 | #include <linux/delay.h> |
85 | #include <linux/init.h> |
86 | #include <linux/slab.h> |
87 | #include <linux/workqueue.h> |
88 | #include "slip.h" |
89 | #ifdef CONFIG_INET |
90 | #include <linux/ip.h> |
91 | #include <linux/tcp.h> |
92 | #include <net/slhc_vj.h> |
93 | #endif |
94 | |
95 | #define SLIP_VERSION "0.8.4-NET3.019-NEWTTY" |
96 | |
97 | static struct net_device **slip_devs; |
98 | |
99 | static int slip_maxdev = SL_NRUNIT; |
100 | module_param(slip_maxdev, int, 0); |
101 | MODULE_PARM_DESC(slip_maxdev, "Maximum number of slip devices" ); |
102 | |
103 | static int slip_esc(unsigned char *p, unsigned char *d, int len); |
104 | static void slip_unesc(struct slip *sl, unsigned char c); |
105 | #ifdef CONFIG_SLIP_MODE_SLIP6 |
106 | static int slip_esc6(unsigned char *p, unsigned char *d, int len); |
107 | static void slip_unesc6(struct slip *sl, unsigned char c); |
108 | #endif |
109 | #ifdef CONFIG_SLIP_SMART |
110 | static void sl_keepalive(struct timer_list *t); |
111 | static void sl_outfill(struct timer_list *t); |
112 | static int sl_siocdevprivate(struct net_device *dev, struct ifreq *rq, void __user *data, int cmd); |
113 | #endif |
114 | |
115 | /******************************** |
116 | * Buffer administration routines: |
117 | * sl_alloc_bufs() |
118 | * sl_free_bufs() |
119 | * sl_realloc_bufs() |
120 | * |
121 | * NOTE: sl_realloc_bufs != sl_free_bufs + sl_alloc_bufs, because |
122 | * sl_realloc_bufs provides strong atomicity and reallocation |
123 | * on actively running device. |
124 | *********************************/ |
125 | |
126 | /* |
127 | Allocate channel buffers. |
128 | */ |
129 | |
130 | static int sl_alloc_bufs(struct slip *sl, int mtu) |
131 | { |
132 | int err = -ENOBUFS; |
133 | unsigned long len; |
134 | char *rbuff = NULL; |
135 | char *xbuff = NULL; |
136 | #ifdef SL_INCLUDE_CSLIP |
137 | char *cbuff = NULL; |
138 | struct slcompress *slcomp = NULL; |
139 | #endif |
140 | |
141 | /* |
142 | * Allocate the SLIP frame buffers: |
143 | * |
144 | * rbuff Receive buffer. |
145 | * xbuff Transmit buffer. |
146 | * cbuff Temporary compression buffer. |
147 | */ |
148 | len = mtu * 2; |
149 | |
150 | /* |
151 | * allow for arrival of larger UDP packets, even if we say not to |
152 | * also fixes a bug in which SunOS sends 512-byte packets even with |
153 | * an MSS of 128 |
154 | */ |
155 | if (len < 576 * 2) |
156 | len = 576 * 2; |
157 | rbuff = kmalloc(size: len + 4, GFP_KERNEL); |
158 | if (rbuff == NULL) |
159 | goto err_exit; |
160 | xbuff = kmalloc(size: len + 4, GFP_KERNEL); |
161 | if (xbuff == NULL) |
162 | goto err_exit; |
163 | #ifdef SL_INCLUDE_CSLIP |
164 | cbuff = kmalloc(size: len + 4, GFP_KERNEL); |
165 | if (cbuff == NULL) |
166 | goto err_exit; |
167 | slcomp = slhc_init(rslots: 16, tslots: 16); |
168 | if (IS_ERR(ptr: slcomp)) |
169 | goto err_exit; |
170 | #endif |
171 | spin_lock_bh(lock: &sl->lock); |
172 | if (sl->tty == NULL) { |
173 | spin_unlock_bh(lock: &sl->lock); |
174 | err = -ENODEV; |
175 | goto err_exit; |
176 | } |
177 | sl->mtu = mtu; |
178 | sl->buffsize = len; |
179 | sl->rcount = 0; |
180 | sl->xleft = 0; |
181 | rbuff = xchg(&sl->rbuff, rbuff); |
182 | xbuff = xchg(&sl->xbuff, xbuff); |
183 | #ifdef SL_INCLUDE_CSLIP |
184 | cbuff = xchg(&sl->cbuff, cbuff); |
185 | slcomp = xchg(&sl->slcomp, slcomp); |
186 | #endif |
187 | #ifdef CONFIG_SLIP_MODE_SLIP6 |
188 | sl->xdata = 0; |
189 | sl->xbits = 0; |
190 | #endif |
191 | spin_unlock_bh(lock: &sl->lock); |
192 | err = 0; |
193 | |
194 | /* Cleanup */ |
195 | err_exit: |
196 | #ifdef SL_INCLUDE_CSLIP |
197 | kfree(objp: cbuff); |
198 | slhc_free(comp: slcomp); |
199 | #endif |
200 | kfree(objp: xbuff); |
201 | kfree(objp: rbuff); |
202 | return err; |
203 | } |
204 | |
205 | /* Free a SLIP channel buffers. */ |
206 | static void sl_free_bufs(struct slip *sl) |
207 | { |
208 | /* Free all SLIP frame buffers. */ |
209 | kfree(xchg(&sl->rbuff, NULL)); |
210 | kfree(xchg(&sl->xbuff, NULL)); |
211 | #ifdef SL_INCLUDE_CSLIP |
212 | kfree(xchg(&sl->cbuff, NULL)); |
213 | slhc_free(xchg(&sl->slcomp, NULL)); |
214 | #endif |
215 | } |
216 | |
217 | /* |
218 | Reallocate slip channel buffers. |
219 | */ |
220 | |
221 | static int sl_realloc_bufs(struct slip *sl, int mtu) |
222 | { |
223 | int err = 0; |
224 | struct net_device *dev = sl->dev; |
225 | unsigned char *xbuff, *rbuff; |
226 | #ifdef SL_INCLUDE_CSLIP |
227 | unsigned char *cbuff; |
228 | #endif |
229 | int len = mtu * 2; |
230 | |
231 | /* |
232 | * allow for arrival of larger UDP packets, even if we say not to |
233 | * also fixes a bug in which SunOS sends 512-byte packets even with |
234 | * an MSS of 128 |
235 | */ |
236 | if (len < 576 * 2) |
237 | len = 576 * 2; |
238 | |
239 | xbuff = kmalloc(size: len + 4, GFP_ATOMIC); |
240 | rbuff = kmalloc(size: len + 4, GFP_ATOMIC); |
241 | #ifdef SL_INCLUDE_CSLIP |
242 | cbuff = kmalloc(size: len + 4, GFP_ATOMIC); |
243 | #endif |
244 | |
245 | |
246 | #ifdef SL_INCLUDE_CSLIP |
247 | if (xbuff == NULL || rbuff == NULL || cbuff == NULL) { |
248 | #else |
249 | if (xbuff == NULL || rbuff == NULL) { |
250 | #endif |
251 | if (mtu > sl->mtu) { |
252 | printk(KERN_WARNING "%s: unable to grow slip buffers, MTU change cancelled.\n" , |
253 | dev->name); |
254 | err = -ENOBUFS; |
255 | } |
256 | goto done; |
257 | } |
258 | spin_lock_bh(lock: &sl->lock); |
259 | |
260 | err = -ENODEV; |
261 | if (sl->tty == NULL) |
262 | goto done_on_bh; |
263 | |
264 | xbuff = xchg(&sl->xbuff, xbuff); |
265 | rbuff = xchg(&sl->rbuff, rbuff); |
266 | #ifdef SL_INCLUDE_CSLIP |
267 | cbuff = xchg(&sl->cbuff, cbuff); |
268 | #endif |
269 | if (sl->xleft) { |
270 | if (sl->xleft <= len) { |
271 | memcpy(sl->xbuff, sl->xhead, sl->xleft); |
272 | } else { |
273 | sl->xleft = 0; |
274 | dev->stats.tx_dropped++; |
275 | } |
276 | } |
277 | sl->xhead = sl->xbuff; |
278 | |
279 | if (sl->rcount) { |
280 | if (sl->rcount <= len) { |
281 | memcpy(sl->rbuff, rbuff, sl->rcount); |
282 | } else { |
283 | sl->rcount = 0; |
284 | dev->stats.rx_over_errors++; |
285 | set_bit(SLF_ERROR, addr: &sl->flags); |
286 | } |
287 | } |
288 | sl->mtu = mtu; |
289 | dev->mtu = mtu; |
290 | sl->buffsize = len; |
291 | err = 0; |
292 | |
293 | done_on_bh: |
294 | spin_unlock_bh(lock: &sl->lock); |
295 | |
296 | done: |
297 | kfree(objp: xbuff); |
298 | kfree(objp: rbuff); |
299 | #ifdef SL_INCLUDE_CSLIP |
300 | kfree(objp: cbuff); |
301 | #endif |
302 | return err; |
303 | } |
304 | |
305 | |
306 | /* Set the "sending" flag. This must be atomic hence the set_bit. */ |
307 | static inline void sl_lock(struct slip *sl) |
308 | { |
309 | netif_stop_queue(dev: sl->dev); |
310 | } |
311 | |
312 | |
313 | /* Clear the "sending" flag. This must be atomic, hence the ASM. */ |
314 | static inline void sl_unlock(struct slip *sl) |
315 | { |
316 | netif_wake_queue(dev: sl->dev); |
317 | } |
318 | |
319 | /* Send one completely decapsulated IP datagram to the IP layer. */ |
320 | static void sl_bump(struct slip *sl) |
321 | { |
322 | struct net_device *dev = sl->dev; |
323 | struct sk_buff *skb; |
324 | int count; |
325 | |
326 | count = sl->rcount; |
327 | #ifdef SL_INCLUDE_CSLIP |
328 | if (sl->mode & (SL_MODE_ADAPTIVE | SL_MODE_CSLIP)) { |
329 | unsigned char c = sl->rbuff[0]; |
330 | if (c & SL_TYPE_COMPRESSED_TCP) { |
331 | /* ignore compressed packets when CSLIP is off */ |
332 | if (!(sl->mode & SL_MODE_CSLIP)) { |
333 | printk(KERN_WARNING "%s: compressed packet ignored\n" , dev->name); |
334 | return; |
335 | } |
336 | /* make sure we've reserved enough space for uncompress |
337 | to use */ |
338 | if (count + 80 > sl->buffsize) { |
339 | dev->stats.rx_over_errors++; |
340 | return; |
341 | } |
342 | count = slhc_uncompress(comp: sl->slcomp, icp: sl->rbuff, isize: count); |
343 | if (count <= 0) |
344 | return; |
345 | } else if (c >= SL_TYPE_UNCOMPRESSED_TCP) { |
346 | if (!(sl->mode & SL_MODE_CSLIP)) { |
347 | /* turn on header compression */ |
348 | sl->mode |= SL_MODE_CSLIP; |
349 | sl->mode &= ~SL_MODE_ADAPTIVE; |
350 | printk(KERN_INFO "%s: header compression turned on\n" , dev->name); |
351 | } |
352 | sl->rbuff[0] &= 0x4f; |
353 | if (slhc_remember(comp: sl->slcomp, icp: sl->rbuff, isize: count) <= 0) |
354 | return; |
355 | } |
356 | } |
357 | #endif /* SL_INCLUDE_CSLIP */ |
358 | |
359 | dev->stats.rx_bytes += count; |
360 | |
361 | skb = dev_alloc_skb(length: count); |
362 | if (skb == NULL) { |
363 | printk(KERN_WARNING "%s: memory squeeze, dropping packet.\n" , dev->name); |
364 | dev->stats.rx_dropped++; |
365 | return; |
366 | } |
367 | skb->dev = dev; |
368 | skb_put_data(skb, data: sl->rbuff, len: count); |
369 | skb_reset_mac_header(skb); |
370 | skb->protocol = htons(ETH_P_IP); |
371 | netif_rx(skb); |
372 | dev->stats.rx_packets++; |
373 | } |
374 | |
375 | /* Encapsulate one IP datagram and stuff into a TTY queue. */ |
376 | static void sl_encaps(struct slip *sl, unsigned char *icp, int len) |
377 | { |
378 | unsigned char *p; |
379 | int actual, count; |
380 | |
381 | if (len > sl->mtu) { /* Sigh, shouldn't occur BUT ... */ |
382 | printk(KERN_WARNING "%s: truncating oversized transmit packet!\n" , sl->dev->name); |
383 | sl->dev->stats.tx_dropped++; |
384 | sl_unlock(sl); |
385 | return; |
386 | } |
387 | |
388 | p = icp; |
389 | #ifdef SL_INCLUDE_CSLIP |
390 | if (sl->mode & SL_MODE_CSLIP) |
391 | len = slhc_compress(comp: sl->slcomp, icp: p, isize: len, ocp: sl->cbuff, cpp: &p, compress_cid: 1); |
392 | #endif |
393 | #ifdef CONFIG_SLIP_MODE_SLIP6 |
394 | if (sl->mode & SL_MODE_SLIP6) |
395 | count = slip_esc6(p, d: sl->xbuff, len); |
396 | else |
397 | #endif |
398 | count = slip_esc(p, d: sl->xbuff, len); |
399 | |
400 | /* Order of next two lines is *very* important. |
401 | * When we are sending a little amount of data, |
402 | * the transfer may be completed inside the ops->write() |
403 | * routine, because it's running with interrupts enabled. |
404 | * In this case we *never* got WRITE_WAKEUP event, |
405 | * if we did not request it before write operation. |
406 | * 14 Oct 1994 Dmitry Gorodchanin. |
407 | */ |
408 | set_bit(TTY_DO_WRITE_WAKEUP, addr: &sl->tty->flags); |
409 | actual = sl->tty->ops->write(sl->tty, sl->xbuff, count); |
410 | #ifdef SL_CHECK_TRANSMIT |
411 | netif_trans_update(dev: sl->dev); |
412 | #endif |
413 | sl->xleft = count - actual; |
414 | sl->xhead = sl->xbuff + actual; |
415 | #ifdef CONFIG_SLIP_SMART |
416 | /* VSV */ |
417 | clear_bit(SLF_OUTWAIT, addr: &sl->flags); /* reset outfill flag */ |
418 | #endif |
419 | } |
420 | |
421 | /* Write out any remaining transmit buffer. Scheduled when tty is writable */ |
422 | static void slip_transmit(struct work_struct *work) |
423 | { |
424 | struct slip *sl = container_of(work, struct slip, tx_work); |
425 | int actual; |
426 | |
427 | spin_lock_bh(lock: &sl->lock); |
428 | /* First make sure we're connected. */ |
429 | if (!sl->tty || sl->magic != SLIP_MAGIC || !netif_running(dev: sl->dev)) { |
430 | spin_unlock_bh(lock: &sl->lock); |
431 | return; |
432 | } |
433 | |
434 | if (sl->xleft <= 0) { |
435 | /* Now serial buffer is almost free & we can start |
436 | * transmission of another packet */ |
437 | sl->dev->stats.tx_packets++; |
438 | clear_bit(TTY_DO_WRITE_WAKEUP, addr: &sl->tty->flags); |
439 | spin_unlock_bh(lock: &sl->lock); |
440 | sl_unlock(sl); |
441 | return; |
442 | } |
443 | |
444 | actual = sl->tty->ops->write(sl->tty, sl->xhead, sl->xleft); |
445 | sl->xleft -= actual; |
446 | sl->xhead += actual; |
447 | spin_unlock_bh(lock: &sl->lock); |
448 | } |
449 | |
450 | /* |
451 | * Called by the driver when there's room for more data. |
452 | * Schedule the transmit. |
453 | */ |
454 | static void slip_write_wakeup(struct tty_struct *tty) |
455 | { |
456 | struct slip *sl; |
457 | |
458 | rcu_read_lock(); |
459 | sl = rcu_dereference(tty->disc_data); |
460 | if (sl) |
461 | schedule_work(work: &sl->tx_work); |
462 | rcu_read_unlock(); |
463 | } |
464 | |
465 | static void sl_tx_timeout(struct net_device *dev, unsigned int txqueue) |
466 | { |
467 | struct slip *sl = netdev_priv(dev); |
468 | |
469 | spin_lock(lock: &sl->lock); |
470 | |
471 | if (netif_queue_stopped(dev)) { |
472 | if (!netif_running(dev) || !sl->tty) |
473 | goto out; |
474 | |
475 | /* May be we must check transmitter timeout here ? |
476 | * 14 Oct 1994 Dmitry Gorodchanin. |
477 | */ |
478 | #ifdef SL_CHECK_TRANSMIT |
479 | if (time_before(jiffies, dev_trans_start(dev) + 20 * HZ)) { |
480 | /* 20 sec timeout not reached */ |
481 | goto out; |
482 | } |
483 | printk(KERN_WARNING "%s: transmit timed out, %s?\n" , |
484 | dev->name, |
485 | (tty_chars_in_buffer(sl->tty) || sl->xleft) ? |
486 | "bad line quality" : "driver error" ); |
487 | sl->xleft = 0; |
488 | clear_bit(TTY_DO_WRITE_WAKEUP, addr: &sl->tty->flags); |
489 | sl_unlock(sl); |
490 | #endif |
491 | } |
492 | out: |
493 | spin_unlock(lock: &sl->lock); |
494 | } |
495 | |
496 | |
497 | /* Encapsulate an IP datagram and kick it into a TTY queue. */ |
498 | static netdev_tx_t |
499 | sl_xmit(struct sk_buff *skb, struct net_device *dev) |
500 | { |
501 | struct slip *sl = netdev_priv(dev); |
502 | |
503 | spin_lock(lock: &sl->lock); |
504 | if (!netif_running(dev)) { |
505 | spin_unlock(lock: &sl->lock); |
506 | printk(KERN_WARNING "%s: xmit call when iface is down\n" , dev->name); |
507 | dev_kfree_skb(skb); |
508 | return NETDEV_TX_OK; |
509 | } |
510 | if (sl->tty == NULL) { |
511 | spin_unlock(lock: &sl->lock); |
512 | dev_kfree_skb(skb); |
513 | return NETDEV_TX_OK; |
514 | } |
515 | |
516 | sl_lock(sl); |
517 | dev->stats.tx_bytes += skb->len; |
518 | sl_encaps(sl, icp: skb->data, len: skb->len); |
519 | spin_unlock(lock: &sl->lock); |
520 | |
521 | dev_kfree_skb(skb); |
522 | return NETDEV_TX_OK; |
523 | } |
524 | |
525 | |
526 | /****************************************** |
527 | * Routines looking at netdevice side. |
528 | ******************************************/ |
529 | |
530 | /* Netdevice UP -> DOWN routine */ |
531 | |
532 | static int |
533 | sl_close(struct net_device *dev) |
534 | { |
535 | struct slip *sl = netdev_priv(dev); |
536 | |
537 | spin_lock_bh(lock: &sl->lock); |
538 | if (sl->tty) |
539 | /* TTY discipline is running. */ |
540 | clear_bit(TTY_DO_WRITE_WAKEUP, addr: &sl->tty->flags); |
541 | netif_stop_queue(dev); |
542 | sl->rcount = 0; |
543 | sl->xleft = 0; |
544 | spin_unlock_bh(lock: &sl->lock); |
545 | |
546 | return 0; |
547 | } |
548 | |
549 | /* Netdevice DOWN -> UP routine */ |
550 | |
551 | static int sl_open(struct net_device *dev) |
552 | { |
553 | struct slip *sl = netdev_priv(dev); |
554 | |
555 | if (sl->tty == NULL) |
556 | return -ENODEV; |
557 | |
558 | sl->flags &= (1 << SLF_INUSE); |
559 | netif_start_queue(dev); |
560 | return 0; |
561 | } |
562 | |
563 | /* Netdevice change MTU request */ |
564 | |
565 | static int sl_change_mtu(struct net_device *dev, int new_mtu) |
566 | { |
567 | struct slip *sl = netdev_priv(dev); |
568 | |
569 | return sl_realloc_bufs(sl, mtu: new_mtu); |
570 | } |
571 | |
572 | /* Netdevice get statistics request */ |
573 | |
574 | static void |
575 | sl_get_stats64(struct net_device *dev, struct rtnl_link_stats64 *stats) |
576 | { |
577 | struct net_device_stats *devstats = &dev->stats; |
578 | #ifdef SL_INCLUDE_CSLIP |
579 | struct slip *sl = netdev_priv(dev); |
580 | struct slcompress *comp = sl->slcomp; |
581 | #endif |
582 | stats->rx_packets = devstats->rx_packets; |
583 | stats->tx_packets = devstats->tx_packets; |
584 | stats->rx_bytes = devstats->rx_bytes; |
585 | stats->tx_bytes = devstats->tx_bytes; |
586 | stats->rx_dropped = devstats->rx_dropped; |
587 | stats->tx_dropped = devstats->tx_dropped; |
588 | stats->tx_errors = devstats->tx_errors; |
589 | stats->rx_errors = devstats->rx_errors; |
590 | stats->rx_over_errors = devstats->rx_over_errors; |
591 | |
592 | #ifdef SL_INCLUDE_CSLIP |
593 | if (comp) { |
594 | /* Generic compressed statistics */ |
595 | stats->rx_compressed = comp->sls_i_compressed; |
596 | stats->tx_compressed = comp->sls_o_compressed; |
597 | |
598 | /* Are we really still needs this? */ |
599 | stats->rx_fifo_errors += comp->sls_i_compressed; |
600 | stats->rx_dropped += comp->sls_i_tossed; |
601 | stats->tx_fifo_errors += comp->sls_o_compressed; |
602 | stats->collisions += comp->sls_o_misses; |
603 | } |
604 | #endif |
605 | } |
606 | |
607 | /* Netdevice register callback */ |
608 | |
609 | static int sl_init(struct net_device *dev) |
610 | { |
611 | struct slip *sl = netdev_priv(dev); |
612 | |
613 | /* |
614 | * Finish setting up the DEVICE info. |
615 | */ |
616 | |
617 | dev->mtu = sl->mtu; |
618 | dev->type = ARPHRD_SLIP + sl->mode; |
619 | #ifdef SL_CHECK_TRANSMIT |
620 | dev->watchdog_timeo = 20*HZ; |
621 | #endif |
622 | return 0; |
623 | } |
624 | |
625 | |
626 | static void sl_uninit(struct net_device *dev) |
627 | { |
628 | struct slip *sl = netdev_priv(dev); |
629 | |
630 | sl_free_bufs(sl); |
631 | } |
632 | |
633 | /* Hook the destructor so we can free slip devices at the right point in time */ |
634 | static void sl_free_netdev(struct net_device *dev) |
635 | { |
636 | int i = dev->base_addr; |
637 | |
638 | slip_devs[i] = NULL; |
639 | } |
640 | |
641 | static const struct net_device_ops sl_netdev_ops = { |
642 | .ndo_init = sl_init, |
643 | .ndo_uninit = sl_uninit, |
644 | .ndo_open = sl_open, |
645 | .ndo_stop = sl_close, |
646 | .ndo_start_xmit = sl_xmit, |
647 | .ndo_get_stats64 = sl_get_stats64, |
648 | .ndo_change_mtu = sl_change_mtu, |
649 | .ndo_tx_timeout = sl_tx_timeout, |
650 | #ifdef CONFIG_SLIP_SMART |
651 | .ndo_siocdevprivate = sl_siocdevprivate, |
652 | #endif |
653 | }; |
654 | |
655 | |
656 | static void sl_setup(struct net_device *dev) |
657 | { |
658 | dev->netdev_ops = &sl_netdev_ops; |
659 | dev->needs_free_netdev = true; |
660 | dev->priv_destructor = sl_free_netdev; |
661 | |
662 | dev->hard_header_len = 0; |
663 | dev->addr_len = 0; |
664 | dev->tx_queue_len = 10; |
665 | |
666 | /* MTU range: 68 - 65534 */ |
667 | dev->min_mtu = 68; |
668 | dev->max_mtu = 65534; |
669 | |
670 | /* New-style flags. */ |
671 | dev->flags = IFF_NOARP|IFF_POINTOPOINT|IFF_MULTICAST; |
672 | } |
673 | |
674 | /****************************************** |
675 | Routines looking at TTY side. |
676 | ******************************************/ |
677 | |
678 | |
679 | /* |
680 | * Handle the 'receiver data ready' interrupt. |
681 | * This function is called by the 'tty_io' module in the kernel when |
682 | * a block of SLIP data has been received, which can now be decapsulated |
683 | * and sent on to some IP layer for further processing. This will not |
684 | * be re-entered while running but other ldisc functions may be called |
685 | * in parallel |
686 | */ |
687 | |
688 | static void slip_receive_buf(struct tty_struct *tty, const u8 *cp, const u8 *fp, |
689 | size_t count) |
690 | { |
691 | struct slip *sl = tty->disc_data; |
692 | |
693 | if (!sl || sl->magic != SLIP_MAGIC || !netif_running(dev: sl->dev)) |
694 | return; |
695 | |
696 | /* Read the characters out of the buffer */ |
697 | while (count--) { |
698 | if (fp && *fp++) { |
699 | if (!test_and_set_bit(SLF_ERROR, addr: &sl->flags)) |
700 | sl->dev->stats.rx_errors++; |
701 | cp++; |
702 | continue; |
703 | } |
704 | #ifdef CONFIG_SLIP_MODE_SLIP6 |
705 | if (sl->mode & SL_MODE_SLIP6) |
706 | slip_unesc6(sl, c: *cp++); |
707 | else |
708 | #endif |
709 | slip_unesc(sl, c: *cp++); |
710 | } |
711 | } |
712 | |
713 | /************************************ |
714 | * slip_open helper routines. |
715 | ************************************/ |
716 | |
717 | /* Collect hanged up channels */ |
718 | static void sl_sync(void) |
719 | { |
720 | int i; |
721 | struct net_device *dev; |
722 | struct slip *sl; |
723 | |
724 | for (i = 0; i < slip_maxdev; i++) { |
725 | dev = slip_devs[i]; |
726 | if (dev == NULL) |
727 | break; |
728 | |
729 | sl = netdev_priv(dev); |
730 | if (sl->tty || sl->leased) |
731 | continue; |
732 | if (dev->flags & IFF_UP) |
733 | dev_close(dev); |
734 | } |
735 | } |
736 | |
737 | |
738 | /* Find a free SLIP channel, and link in this `tty' line. */ |
739 | static struct slip *sl_alloc(void) |
740 | { |
741 | int i; |
742 | char name[IFNAMSIZ]; |
743 | struct net_device *dev = NULL; |
744 | struct slip *sl; |
745 | |
746 | for (i = 0; i < slip_maxdev; i++) { |
747 | dev = slip_devs[i]; |
748 | if (dev == NULL) |
749 | break; |
750 | } |
751 | /* Sorry, too many, all slots in use */ |
752 | if (i >= slip_maxdev) |
753 | return NULL; |
754 | |
755 | sprintf(buf: name, fmt: "sl%d" , i); |
756 | dev = alloc_netdev(sizeof(*sl), name, NET_NAME_UNKNOWN, sl_setup); |
757 | if (!dev) |
758 | return NULL; |
759 | |
760 | dev->base_addr = i; |
761 | sl = netdev_priv(dev); |
762 | |
763 | /* Initialize channel control data */ |
764 | sl->magic = SLIP_MAGIC; |
765 | sl->dev = dev; |
766 | spin_lock_init(&sl->lock); |
767 | INIT_WORK(&sl->tx_work, slip_transmit); |
768 | sl->mode = SL_MODE_DEFAULT; |
769 | #ifdef CONFIG_SLIP_SMART |
770 | /* initialize timer_list struct */ |
771 | timer_setup(&sl->keepalive_timer, sl_keepalive, 0); |
772 | timer_setup(&sl->outfill_timer, sl_outfill, 0); |
773 | #endif |
774 | slip_devs[i] = dev; |
775 | return sl; |
776 | } |
777 | |
778 | /* |
779 | * Open the high-level part of the SLIP channel. |
780 | * This function is called by the TTY module when the |
781 | * SLIP line discipline is called for. Because we are |
782 | * sure the tty line exists, we only have to link it to |
783 | * a free SLIP channel... |
784 | * |
785 | * Called in process context serialized from other ldisc calls. |
786 | */ |
787 | |
788 | static int slip_open(struct tty_struct *tty) |
789 | { |
790 | struct slip *sl; |
791 | int err; |
792 | |
793 | if (!capable(CAP_NET_ADMIN)) |
794 | return -EPERM; |
795 | |
796 | if (tty->ops->write == NULL) |
797 | return -EOPNOTSUPP; |
798 | |
799 | /* RTnetlink lock is misused here to serialize concurrent |
800 | opens of slip channels. There are better ways, but it is |
801 | the simplest one. |
802 | */ |
803 | rtnl_lock(); |
804 | |
805 | /* Collect hanged up channels. */ |
806 | sl_sync(); |
807 | |
808 | sl = tty->disc_data; |
809 | |
810 | err = -EEXIST; |
811 | /* First make sure we're not already connected. */ |
812 | if (sl && sl->magic == SLIP_MAGIC) |
813 | goto err_exit; |
814 | |
815 | /* OK. Find a free SLIP channel to use. */ |
816 | err = -ENFILE; |
817 | sl = sl_alloc(); |
818 | if (sl == NULL) |
819 | goto err_exit; |
820 | |
821 | sl->tty = tty; |
822 | tty->disc_data = sl; |
823 | sl->pid = current->pid; |
824 | |
825 | if (!test_bit(SLF_INUSE, &sl->flags)) { |
826 | /* Perform the low-level SLIP initialization. */ |
827 | err = sl_alloc_bufs(sl, SL_MTU); |
828 | if (err) |
829 | goto err_free_chan; |
830 | |
831 | set_bit(SLF_INUSE, addr: &sl->flags); |
832 | |
833 | err = register_netdevice(dev: sl->dev); |
834 | if (err) |
835 | goto err_free_bufs; |
836 | } |
837 | |
838 | #ifdef CONFIG_SLIP_SMART |
839 | if (sl->keepalive) { |
840 | sl->keepalive_timer.expires = jiffies + sl->keepalive * HZ; |
841 | add_timer(timer: &sl->keepalive_timer); |
842 | } |
843 | if (sl->outfill) { |
844 | sl->outfill_timer.expires = jiffies + sl->outfill * HZ; |
845 | add_timer(timer: &sl->outfill_timer); |
846 | } |
847 | #endif |
848 | |
849 | /* Done. We have linked the TTY line to a channel. */ |
850 | rtnl_unlock(); |
851 | tty->receive_room = 65536; /* We don't flow control */ |
852 | |
853 | /* TTY layer expects 0 on success */ |
854 | return 0; |
855 | |
856 | err_free_bufs: |
857 | sl_free_bufs(sl); |
858 | |
859 | err_free_chan: |
860 | sl->tty = NULL; |
861 | tty->disc_data = NULL; |
862 | clear_bit(SLF_INUSE, addr: &sl->flags); |
863 | sl_free_netdev(dev: sl->dev); |
864 | /* do not call free_netdev before rtnl_unlock */ |
865 | rtnl_unlock(); |
866 | free_netdev(dev: sl->dev); |
867 | return err; |
868 | |
869 | err_exit: |
870 | rtnl_unlock(); |
871 | |
872 | /* Count references from TTY module */ |
873 | return err; |
874 | } |
875 | |
876 | /* |
877 | * Close down a SLIP channel. |
878 | * This means flushing out any pending queues, and then returning. This |
879 | * call is serialized against other ldisc functions. |
880 | * |
881 | * We also use this method fo a hangup event |
882 | */ |
883 | |
884 | static void slip_close(struct tty_struct *tty) |
885 | { |
886 | struct slip *sl = tty->disc_data; |
887 | |
888 | /* First make sure we're connected. */ |
889 | if (!sl || sl->magic != SLIP_MAGIC || sl->tty != tty) |
890 | return; |
891 | |
892 | spin_lock_bh(lock: &sl->lock); |
893 | rcu_assign_pointer(tty->disc_data, NULL); |
894 | sl->tty = NULL; |
895 | spin_unlock_bh(lock: &sl->lock); |
896 | |
897 | synchronize_rcu(); |
898 | flush_work(work: &sl->tx_work); |
899 | |
900 | /* VSV = very important to remove timers */ |
901 | #ifdef CONFIG_SLIP_SMART |
902 | del_timer_sync(timer: &sl->keepalive_timer); |
903 | del_timer_sync(timer: &sl->outfill_timer); |
904 | #endif |
905 | /* Flush network side */ |
906 | unregister_netdev(dev: sl->dev); |
907 | /* This will complete via sl_free_netdev */ |
908 | } |
909 | |
910 | static void slip_hangup(struct tty_struct *tty) |
911 | { |
912 | slip_close(tty); |
913 | } |
914 | /************************************************************************ |
915 | * STANDARD SLIP ENCAPSULATION * |
916 | ************************************************************************/ |
917 | |
918 | static int slip_esc(unsigned char *s, unsigned char *d, int len) |
919 | { |
920 | unsigned char *ptr = d; |
921 | unsigned char c; |
922 | |
923 | /* |
924 | * Send an initial END character to flush out any |
925 | * data that may have accumulated in the receiver |
926 | * due to line noise. |
927 | */ |
928 | |
929 | *ptr++ = END; |
930 | |
931 | /* |
932 | * For each byte in the packet, send the appropriate |
933 | * character sequence, according to the SLIP protocol. |
934 | */ |
935 | |
936 | while (len-- > 0) { |
937 | switch (c = *s++) { |
938 | case END: |
939 | *ptr++ = ESC; |
940 | *ptr++ = ESC_END; |
941 | break; |
942 | case ESC: |
943 | *ptr++ = ESC; |
944 | *ptr++ = ESC_ESC; |
945 | break; |
946 | default: |
947 | *ptr++ = c; |
948 | break; |
949 | } |
950 | } |
951 | *ptr++ = END; |
952 | return ptr - d; |
953 | } |
954 | |
955 | static void slip_unesc(struct slip *sl, unsigned char s) |
956 | { |
957 | |
958 | switch (s) { |
959 | case END: |
960 | #ifdef CONFIG_SLIP_SMART |
961 | /* drop keeptest bit = VSV */ |
962 | if (test_bit(SLF_KEEPTEST, &sl->flags)) |
963 | clear_bit(SLF_KEEPTEST, addr: &sl->flags); |
964 | #endif |
965 | |
966 | if (!test_and_clear_bit(SLF_ERROR, addr: &sl->flags) && |
967 | (sl->rcount > 2)) |
968 | sl_bump(sl); |
969 | clear_bit(SLF_ESCAPE, addr: &sl->flags); |
970 | sl->rcount = 0; |
971 | return; |
972 | |
973 | case ESC: |
974 | set_bit(SLF_ESCAPE, addr: &sl->flags); |
975 | return; |
976 | case ESC_ESC: |
977 | if (test_and_clear_bit(SLF_ESCAPE, addr: &sl->flags)) |
978 | s = ESC; |
979 | break; |
980 | case ESC_END: |
981 | if (test_and_clear_bit(SLF_ESCAPE, addr: &sl->flags)) |
982 | s = END; |
983 | break; |
984 | } |
985 | if (!test_bit(SLF_ERROR, &sl->flags)) { |
986 | if (sl->rcount < sl->buffsize) { |
987 | sl->rbuff[sl->rcount++] = s; |
988 | return; |
989 | } |
990 | sl->dev->stats.rx_over_errors++; |
991 | set_bit(SLF_ERROR, addr: &sl->flags); |
992 | } |
993 | } |
994 | |
995 | |
996 | #ifdef CONFIG_SLIP_MODE_SLIP6 |
997 | /************************************************************************ |
998 | * 6 BIT SLIP ENCAPSULATION * |
999 | ************************************************************************/ |
1000 | |
1001 | static int slip_esc6(unsigned char *s, unsigned char *d, int len) |
1002 | { |
1003 | unsigned char *ptr = d; |
1004 | unsigned char c; |
1005 | int i; |
1006 | unsigned short v = 0; |
1007 | short bits = 0; |
1008 | |
1009 | /* |
1010 | * Send an initial END character to flush out any |
1011 | * data that may have accumulated in the receiver |
1012 | * due to line noise. |
1013 | */ |
1014 | |
1015 | *ptr++ = 0x70; |
1016 | |
1017 | /* |
1018 | * Encode the packet into printable ascii characters |
1019 | */ |
1020 | |
1021 | for (i = 0; i < len; ++i) { |
1022 | v = (v << 8) | s[i]; |
1023 | bits += 8; |
1024 | while (bits >= 6) { |
1025 | bits -= 6; |
1026 | c = 0x30 + ((v >> bits) & 0x3F); |
1027 | *ptr++ = c; |
1028 | } |
1029 | } |
1030 | if (bits) { |
1031 | c = 0x30 + ((v << (6 - bits)) & 0x3F); |
1032 | *ptr++ = c; |
1033 | } |
1034 | *ptr++ = 0x70; |
1035 | return ptr - d; |
1036 | } |
1037 | |
1038 | static void slip_unesc6(struct slip *sl, unsigned char s) |
1039 | { |
1040 | unsigned char c; |
1041 | |
1042 | if (s == 0x70) { |
1043 | #ifdef CONFIG_SLIP_SMART |
1044 | /* drop keeptest bit = VSV */ |
1045 | if (test_bit(SLF_KEEPTEST, &sl->flags)) |
1046 | clear_bit(SLF_KEEPTEST, addr: &sl->flags); |
1047 | #endif |
1048 | |
1049 | if (!test_and_clear_bit(SLF_ERROR, addr: &sl->flags) && |
1050 | (sl->rcount > 2)) |
1051 | sl_bump(sl); |
1052 | sl->rcount = 0; |
1053 | sl->xbits = 0; |
1054 | sl->xdata = 0; |
1055 | } else if (s >= 0x30 && s < 0x70) { |
1056 | sl->xdata = (sl->xdata << 6) | ((s - 0x30) & 0x3F); |
1057 | sl->xbits += 6; |
1058 | if (sl->xbits >= 8) { |
1059 | sl->xbits -= 8; |
1060 | c = (unsigned char)(sl->xdata >> sl->xbits); |
1061 | if (!test_bit(SLF_ERROR, &sl->flags)) { |
1062 | if (sl->rcount < sl->buffsize) { |
1063 | sl->rbuff[sl->rcount++] = c; |
1064 | return; |
1065 | } |
1066 | sl->dev->stats.rx_over_errors++; |
1067 | set_bit(SLF_ERROR, addr: &sl->flags); |
1068 | } |
1069 | } |
1070 | } |
1071 | } |
1072 | #endif /* CONFIG_SLIP_MODE_SLIP6 */ |
1073 | |
1074 | /* Perform I/O control on an active SLIP channel. */ |
1075 | static int slip_ioctl(struct tty_struct *tty, unsigned int cmd, |
1076 | unsigned long arg) |
1077 | { |
1078 | struct slip *sl = tty->disc_data; |
1079 | unsigned int tmp; |
1080 | int __user *p = (int __user *)arg; |
1081 | |
1082 | /* First make sure we're connected. */ |
1083 | if (!sl || sl->magic != SLIP_MAGIC) |
1084 | return -EINVAL; |
1085 | |
1086 | switch (cmd) { |
1087 | case SIOCGIFNAME: |
1088 | tmp = strlen(sl->dev->name) + 1; |
1089 | if (copy_to_user(to: (void __user *)arg, from: sl->dev->name, n: tmp)) |
1090 | return -EFAULT; |
1091 | return 0; |
1092 | |
1093 | case SIOCGIFENCAP: |
1094 | if (put_user(sl->mode, p)) |
1095 | return -EFAULT; |
1096 | return 0; |
1097 | |
1098 | case SIOCSIFENCAP: |
1099 | if (get_user(tmp, p)) |
1100 | return -EFAULT; |
1101 | #ifndef SL_INCLUDE_CSLIP |
1102 | if (tmp & (SL_MODE_CSLIP|SL_MODE_ADAPTIVE)) |
1103 | return -EINVAL; |
1104 | #else |
1105 | if ((tmp & (SL_MODE_ADAPTIVE | SL_MODE_CSLIP)) == |
1106 | (SL_MODE_ADAPTIVE | SL_MODE_CSLIP)) |
1107 | /* return -EINVAL; */ |
1108 | tmp &= ~SL_MODE_ADAPTIVE; |
1109 | #endif |
1110 | #ifndef CONFIG_SLIP_MODE_SLIP6 |
1111 | if (tmp & SL_MODE_SLIP6) |
1112 | return -EINVAL; |
1113 | #endif |
1114 | sl->mode = tmp; |
1115 | sl->dev->type = ARPHRD_SLIP + sl->mode; |
1116 | return 0; |
1117 | |
1118 | case SIOCSIFHWADDR: |
1119 | return -EINVAL; |
1120 | |
1121 | #ifdef CONFIG_SLIP_SMART |
1122 | /* VSV changes start here */ |
1123 | case SIOCSKEEPALIVE: |
1124 | if (get_user(tmp, p)) |
1125 | return -EFAULT; |
1126 | if (tmp > 255) /* max for unchar */ |
1127 | return -EINVAL; |
1128 | |
1129 | spin_lock_bh(lock: &sl->lock); |
1130 | if (!sl->tty) { |
1131 | spin_unlock_bh(lock: &sl->lock); |
1132 | return -ENODEV; |
1133 | } |
1134 | sl->keepalive = (u8)tmp; |
1135 | if (sl->keepalive != 0) { |
1136 | mod_timer(timer: &sl->keepalive_timer, |
1137 | expires: jiffies + sl->keepalive * HZ); |
1138 | set_bit(SLF_KEEPTEST, addr: &sl->flags); |
1139 | } else |
1140 | del_timer(timer: &sl->keepalive_timer); |
1141 | spin_unlock_bh(lock: &sl->lock); |
1142 | return 0; |
1143 | |
1144 | case SIOCGKEEPALIVE: |
1145 | if (put_user(sl->keepalive, p)) |
1146 | return -EFAULT; |
1147 | return 0; |
1148 | |
1149 | case SIOCSOUTFILL: |
1150 | if (get_user(tmp, p)) |
1151 | return -EFAULT; |
1152 | if (tmp > 255) /* max for unchar */ |
1153 | return -EINVAL; |
1154 | spin_lock_bh(lock: &sl->lock); |
1155 | if (!sl->tty) { |
1156 | spin_unlock_bh(lock: &sl->lock); |
1157 | return -ENODEV; |
1158 | } |
1159 | sl->outfill = (u8)tmp; |
1160 | if (sl->outfill != 0) { |
1161 | mod_timer(timer: &sl->outfill_timer, |
1162 | expires: jiffies + sl->outfill * HZ); |
1163 | set_bit(SLF_OUTWAIT, addr: &sl->flags); |
1164 | } else |
1165 | del_timer(timer: &sl->outfill_timer); |
1166 | spin_unlock_bh(lock: &sl->lock); |
1167 | return 0; |
1168 | |
1169 | case SIOCGOUTFILL: |
1170 | if (put_user(sl->outfill, p)) |
1171 | return -EFAULT; |
1172 | return 0; |
1173 | /* VSV changes end */ |
1174 | #endif |
1175 | default: |
1176 | return tty_mode_ioctl(tty, cmd, arg); |
1177 | } |
1178 | } |
1179 | |
1180 | /* VSV changes start here */ |
1181 | #ifdef CONFIG_SLIP_SMART |
1182 | /* function sl_siocdevprivate called from net/core/dev.c |
1183 | to allow get/set outfill/keepalive parameter |
1184 | by ifconfig */ |
1185 | |
1186 | static int sl_siocdevprivate(struct net_device *dev, struct ifreq *rq, |
1187 | void __user *data, int cmd) |
1188 | { |
1189 | struct slip *sl = netdev_priv(dev); |
1190 | unsigned long *p = (unsigned long *)&rq->ifr_ifru; |
1191 | |
1192 | if (sl == NULL) /* Allocation failed ?? */ |
1193 | return -ENODEV; |
1194 | |
1195 | if (in_compat_syscall()) |
1196 | return -EOPNOTSUPP; |
1197 | |
1198 | spin_lock_bh(lock: &sl->lock); |
1199 | |
1200 | if (!sl->tty) { |
1201 | spin_unlock_bh(lock: &sl->lock); |
1202 | return -ENODEV; |
1203 | } |
1204 | |
1205 | switch (cmd) { |
1206 | case SIOCSKEEPALIVE: |
1207 | /* max for unchar */ |
1208 | if ((unsigned)*p > 255) { |
1209 | spin_unlock_bh(lock: &sl->lock); |
1210 | return -EINVAL; |
1211 | } |
1212 | sl->keepalive = (u8)*p; |
1213 | if (sl->keepalive != 0) { |
1214 | sl->keepalive_timer.expires = |
1215 | jiffies + sl->keepalive * HZ; |
1216 | mod_timer(timer: &sl->keepalive_timer, |
1217 | expires: jiffies + sl->keepalive * HZ); |
1218 | set_bit(SLF_KEEPTEST, addr: &sl->flags); |
1219 | } else |
1220 | del_timer(timer: &sl->keepalive_timer); |
1221 | break; |
1222 | |
1223 | case SIOCGKEEPALIVE: |
1224 | *p = sl->keepalive; |
1225 | break; |
1226 | |
1227 | case SIOCSOUTFILL: |
1228 | if ((unsigned)*p > 255) { /* max for unchar */ |
1229 | spin_unlock_bh(lock: &sl->lock); |
1230 | return -EINVAL; |
1231 | } |
1232 | sl->outfill = (u8)*p; |
1233 | if (sl->outfill != 0) { |
1234 | mod_timer(timer: &sl->outfill_timer, |
1235 | expires: jiffies + sl->outfill * HZ); |
1236 | set_bit(SLF_OUTWAIT, addr: &sl->flags); |
1237 | } else |
1238 | del_timer(timer: &sl->outfill_timer); |
1239 | break; |
1240 | |
1241 | case SIOCGOUTFILL: |
1242 | *p = sl->outfill; |
1243 | break; |
1244 | |
1245 | case SIOCSLEASE: |
1246 | /* Resolve race condition, when ioctl'ing hanged up |
1247 | and opened by another process device. |
1248 | */ |
1249 | if (sl->tty != current->signal->tty && |
1250 | sl->pid != current->pid) { |
1251 | spin_unlock_bh(lock: &sl->lock); |
1252 | return -EPERM; |
1253 | } |
1254 | sl->leased = 0; |
1255 | if (*p) |
1256 | sl->leased = 1; |
1257 | break; |
1258 | |
1259 | case SIOCGLEASE: |
1260 | *p = sl->leased; |
1261 | } |
1262 | spin_unlock_bh(lock: &sl->lock); |
1263 | return 0; |
1264 | } |
1265 | #endif |
1266 | /* VSV changes end */ |
1267 | |
1268 | static struct tty_ldisc_ops sl_ldisc = { |
1269 | .owner = THIS_MODULE, |
1270 | .num = N_SLIP, |
1271 | .name = "slip" , |
1272 | .open = slip_open, |
1273 | .close = slip_close, |
1274 | .hangup = slip_hangup, |
1275 | .ioctl = slip_ioctl, |
1276 | .receive_buf = slip_receive_buf, |
1277 | .write_wakeup = slip_write_wakeup, |
1278 | }; |
1279 | |
1280 | static int __init slip_init(void) |
1281 | { |
1282 | int status; |
1283 | |
1284 | if (slip_maxdev < 4) |
1285 | slip_maxdev = 4; /* Sanity */ |
1286 | |
1287 | printk(KERN_INFO "SLIP: version %s (dynamic channels, max=%d)" |
1288 | #ifdef CONFIG_SLIP_MODE_SLIP6 |
1289 | " (6 bit encapsulation enabled)" |
1290 | #endif |
1291 | ".\n" , |
1292 | SLIP_VERSION, slip_maxdev); |
1293 | #if defined(SL_INCLUDE_CSLIP) |
1294 | printk(KERN_INFO "CSLIP: code copyright 1989 Regents of the University of California.\n" ); |
1295 | #endif |
1296 | #ifdef CONFIG_SLIP_SMART |
1297 | printk(KERN_INFO "SLIP linefill/keepalive option.\n" ); |
1298 | #endif |
1299 | |
1300 | slip_devs = kcalloc(n: slip_maxdev, size: sizeof(struct net_device *), |
1301 | GFP_KERNEL); |
1302 | if (!slip_devs) |
1303 | return -ENOMEM; |
1304 | |
1305 | /* Fill in our line protocol discipline, and register it */ |
1306 | status = tty_register_ldisc(new_ldisc: &sl_ldisc); |
1307 | if (status != 0) { |
1308 | printk(KERN_ERR "SLIP: can't register line discipline (err = %d)\n" , status); |
1309 | kfree(objp: slip_devs); |
1310 | } |
1311 | return status; |
1312 | } |
1313 | |
1314 | static void __exit slip_exit(void) |
1315 | { |
1316 | int i; |
1317 | struct net_device *dev; |
1318 | struct slip *sl; |
1319 | unsigned long timeout = jiffies + HZ; |
1320 | int busy = 0; |
1321 | |
1322 | if (slip_devs == NULL) |
1323 | return; |
1324 | |
1325 | /* First of all: check for active disciplines and hangup them. |
1326 | */ |
1327 | do { |
1328 | if (busy) |
1329 | msleep_interruptible(msecs: 100); |
1330 | |
1331 | busy = 0; |
1332 | for (i = 0; i < slip_maxdev; i++) { |
1333 | dev = slip_devs[i]; |
1334 | if (!dev) |
1335 | continue; |
1336 | sl = netdev_priv(dev); |
1337 | spin_lock_bh(lock: &sl->lock); |
1338 | if (sl->tty) { |
1339 | busy++; |
1340 | tty_hangup(tty: sl->tty); |
1341 | } |
1342 | spin_unlock_bh(lock: &sl->lock); |
1343 | } |
1344 | } while (busy && time_before(jiffies, timeout)); |
1345 | |
1346 | /* FIXME: hangup is async so we should wait when doing this second |
1347 | phase */ |
1348 | |
1349 | for (i = 0; i < slip_maxdev; i++) { |
1350 | dev = slip_devs[i]; |
1351 | if (!dev) |
1352 | continue; |
1353 | slip_devs[i] = NULL; |
1354 | |
1355 | sl = netdev_priv(dev); |
1356 | if (sl->tty) { |
1357 | printk(KERN_ERR "%s: tty discipline still running\n" , |
1358 | dev->name); |
1359 | } |
1360 | |
1361 | unregister_netdev(dev); |
1362 | } |
1363 | |
1364 | kfree(objp: slip_devs); |
1365 | slip_devs = NULL; |
1366 | |
1367 | tty_unregister_ldisc(ldisc: &sl_ldisc); |
1368 | } |
1369 | |
1370 | module_init(slip_init); |
1371 | module_exit(slip_exit); |
1372 | |
1373 | #ifdef CONFIG_SLIP_SMART |
1374 | /* |
1375 | * This is start of the code for multislip style line checking |
1376 | * added by Stanislav Voronyi. All changes before marked VSV |
1377 | */ |
1378 | |
1379 | static void sl_outfill(struct timer_list *t) |
1380 | { |
1381 | struct slip *sl = from_timer(sl, t, outfill_timer); |
1382 | |
1383 | spin_lock(lock: &sl->lock); |
1384 | |
1385 | if (sl->tty == NULL) |
1386 | goto out; |
1387 | |
1388 | if (sl->outfill) { |
1389 | if (test_bit(SLF_OUTWAIT, &sl->flags)) { |
1390 | /* no packets were transmitted, do outfill */ |
1391 | #ifdef CONFIG_SLIP_MODE_SLIP6 |
1392 | unsigned char s = (sl->mode & SL_MODE_SLIP6)?0x70:END; |
1393 | #else |
1394 | unsigned char s = END; |
1395 | #endif |
1396 | /* put END into tty queue. Is it right ??? */ |
1397 | if (!netif_queue_stopped(dev: sl->dev)) { |
1398 | /* if device busy no outfill */ |
1399 | sl->tty->ops->write(sl->tty, &s, 1); |
1400 | } |
1401 | } else |
1402 | set_bit(SLF_OUTWAIT, addr: &sl->flags); |
1403 | |
1404 | mod_timer(timer: &sl->outfill_timer, expires: jiffies+sl->outfill*HZ); |
1405 | } |
1406 | out: |
1407 | spin_unlock(lock: &sl->lock); |
1408 | } |
1409 | |
1410 | static void sl_keepalive(struct timer_list *t) |
1411 | { |
1412 | struct slip *sl = from_timer(sl, t, keepalive_timer); |
1413 | |
1414 | spin_lock(lock: &sl->lock); |
1415 | |
1416 | if (sl->tty == NULL) |
1417 | goto out; |
1418 | |
1419 | if (sl->keepalive) { |
1420 | if (test_bit(SLF_KEEPTEST, &sl->flags)) { |
1421 | /* keepalive still high :(, we must hangup */ |
1422 | if (sl->outfill) |
1423 | /* outfill timer must be deleted too */ |
1424 | (void)del_timer(timer: &sl->outfill_timer); |
1425 | printk(KERN_DEBUG "%s: no packets received during keepalive timeout, hangup.\n" , sl->dev->name); |
1426 | /* this must hangup tty & close slip */ |
1427 | tty_hangup(tty: sl->tty); |
1428 | /* I think we need not something else */ |
1429 | goto out; |
1430 | } else |
1431 | set_bit(SLF_KEEPTEST, addr: &sl->flags); |
1432 | |
1433 | mod_timer(timer: &sl->keepalive_timer, expires: jiffies+sl->keepalive*HZ); |
1434 | } |
1435 | out: |
1436 | spin_unlock(lock: &sl->lock); |
1437 | } |
1438 | |
1439 | #endif |
1440 | MODULE_LICENSE("GPL" ); |
1441 | MODULE_ALIAS_LDISC(N_SLIP); |
1442 | |