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63#define SL_CHECK_TRANSMIT
64#include <linux/module.h>
65#include <linux/moduleparam.h>
66
67#include <asm/uaccess.h>
68#include <linux/bitops.h>
69#include <linux/sched.h>
70#include <linux/string.h>
71#include <linux/mm.h>
72#include <linux/interrupt.h>
73#include <linux/in.h>
74#include <linux/tty.h>
75#include <linux/errno.h>
76#include <linux/netdevice.h>
77#include <linux/etherdevice.h>
78#include <linux/skbuff.h>
79#include <linux/rtnetlink.h>
80#include <linux/if_arp.h>
81#include <linux/if_slip.h>
82#include <linux/compat.h>
83#include <linux/delay.h>
84#include <linux/init.h>
85#include <linux/slab.h>
86#include "slip.h"
87#ifdef CONFIG_INET
88#include <linux/ip.h>
89#include <linux/tcp.h>
90#include <net/slhc_vj.h>
91#endif
92
93#define SLIP_VERSION "0.8.4-NET3.019-NEWTTY"
94
95static struct net_device **slip_devs;
96
97static int slip_maxdev = SL_NRUNIT;
98module_param(slip_maxdev, int, 0);
99MODULE_PARM_DESC(slip_maxdev, "Maximum number of slip devices");
100
101static int slip_esc(unsigned char *p, unsigned char *d, int len);
102static void slip_unesc(struct slip *sl, unsigned char c);
103#ifdef CONFIG_SLIP_MODE_SLIP6
104static int slip_esc6(unsigned char *p, unsigned char *d, int len);
105static void slip_unesc6(struct slip *sl, unsigned char c);
106#endif
107#ifdef CONFIG_SLIP_SMART
108static void sl_keepalive(unsigned long sls);
109static void sl_outfill(unsigned long sls);
110static int sl_ioctl(struct net_device *dev, struct ifreq *rq, int cmd);
111#endif
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128static int sl_alloc_bufs(struct slip *sl, int mtu)
129{
130 int err = -ENOBUFS;
131 unsigned long len;
132 char *rbuff = NULL;
133 char *xbuff = NULL;
134#ifdef SL_INCLUDE_CSLIP
135 char *cbuff = NULL;
136 struct slcompress *slcomp = NULL;
137#endif
138
139
140
141
142
143
144
145
146 len = mtu * 2;
147
148
149
150
151
152
153 if (len < 576 * 2)
154 len = 576 * 2;
155 rbuff = kmalloc(len + 4, GFP_KERNEL);
156 if (rbuff == NULL)
157 goto err_exit;
158 xbuff = kmalloc(len + 4, GFP_KERNEL);
159 if (xbuff == NULL)
160 goto err_exit;
161#ifdef SL_INCLUDE_CSLIP
162 cbuff = kmalloc(len + 4, GFP_KERNEL);
163 if (cbuff == NULL)
164 goto err_exit;
165 slcomp = slhc_init(16, 16);
166 if (slcomp == NULL)
167 goto err_exit;
168#endif
169 spin_lock_bh(&sl->lock);
170 if (sl->tty == NULL) {
171 spin_unlock_bh(&sl->lock);
172 err = -ENODEV;
173 goto err_exit;
174 }
175 sl->mtu = mtu;
176 sl->buffsize = len;
177 sl->rcount = 0;
178 sl->xleft = 0;
179 rbuff = xchg(&sl->rbuff, rbuff);
180 xbuff = xchg(&sl->xbuff, xbuff);
181#ifdef SL_INCLUDE_CSLIP
182 cbuff = xchg(&sl->cbuff, cbuff);
183 slcomp = xchg(&sl->slcomp, slcomp);
184#endif
185#ifdef CONFIG_SLIP_MODE_SLIP6
186 sl->xdata = 0;
187 sl->xbits = 0;
188#endif
189 spin_unlock_bh(&sl->lock);
190 err = 0;
191
192
193err_exit:
194#ifdef SL_INCLUDE_CSLIP
195 kfree(cbuff);
196 slhc_free(slcomp);
197#endif
198 kfree(xbuff);
199 kfree(rbuff);
200 return err;
201}
202
203
204static void sl_free_bufs(struct slip *sl)
205{
206
207 kfree(xchg(&sl->rbuff, NULL));
208 kfree(xchg(&sl->xbuff, NULL));
209#ifdef SL_INCLUDE_CSLIP
210 kfree(xchg(&sl->cbuff, NULL));
211 slhc_free(xchg(&sl->slcomp, NULL));
212#endif
213}
214
215
216
217
218
219static int sl_realloc_bufs(struct slip *sl, int mtu)
220{
221 int err = 0;
222 struct net_device *dev = sl->dev;
223 unsigned char *xbuff, *rbuff;
224#ifdef SL_INCLUDE_CSLIP
225 unsigned char *cbuff;
226#endif
227 int len = mtu * 2;
228
229
230
231
232
233
234 if (len < 576 * 2)
235 len = 576 * 2;
236
237 xbuff = kmalloc(len + 4, GFP_ATOMIC);
238 rbuff = kmalloc(len + 4, GFP_ATOMIC);
239#ifdef SL_INCLUDE_CSLIP
240 cbuff = kmalloc(len + 4, GFP_ATOMIC);
241#endif
242
243
244#ifdef SL_INCLUDE_CSLIP
245 if (xbuff == NULL || rbuff == NULL || cbuff == NULL) {
246#else
247 if (xbuff == NULL || rbuff == NULL) {
248#endif
249 if (mtu > sl->mtu) {
250 printk(KERN_WARNING "%s: unable to grow slip buffers, MTU change cancelled.\n",
251 dev->name);
252 err = -ENOBUFS;
253 }
254 goto done;
255 }
256 spin_lock_bh(&sl->lock);
257
258 err = -ENODEV;
259 if (sl->tty == NULL)
260 goto done_on_bh;
261
262 xbuff = xchg(&sl->xbuff, xbuff);
263 rbuff = xchg(&sl->rbuff, rbuff);
264#ifdef SL_INCLUDE_CSLIP
265 cbuff = xchg(&sl->cbuff, cbuff);
266#endif
267 if (sl->xleft) {
268 if (sl->xleft <= len) {
269 memcpy(sl->xbuff, sl->xhead, sl->xleft);
270 } else {
271 sl->xleft = 0;
272 dev->stats.tx_dropped++;
273 }
274 }
275 sl->xhead = sl->xbuff;
276
277 if (sl->rcount) {
278 if (sl->rcount <= len) {
279 memcpy(sl->rbuff, rbuff, sl->rcount);
280 } else {
281 sl->rcount = 0;
282 dev->stats.rx_over_errors++;
283 set_bit(SLF_ERROR, &sl->flags);
284 }
285 }
286 sl->mtu = mtu;
287 dev->mtu = mtu;
288 sl->buffsize = len;
289 err = 0;
290
291done_on_bh:
292 spin_unlock_bh(&sl->lock);
293
294done:
295 kfree(xbuff);
296 kfree(rbuff);
297#ifdef SL_INCLUDE_CSLIP
298 kfree(cbuff);
299#endif
300 return err;
301}
302
303
304
305static inline void sl_lock(struct slip *sl)
306{
307 netif_stop_queue(sl->dev);
308}
309
310
311
312static inline void sl_unlock(struct slip *sl)
313{
314 netif_wake_queue(sl->dev);
315}
316
317
318static void sl_bump(struct slip *sl)
319{
320 struct net_device *dev = sl->dev;
321 struct sk_buff *skb;
322 int count;
323
324 count = sl->rcount;
325#ifdef SL_INCLUDE_CSLIP
326 if (sl->mode & (SL_MODE_ADAPTIVE | SL_MODE_CSLIP)) {
327 unsigned char c = sl->rbuff[0];
328 if (c & SL_TYPE_COMPRESSED_TCP) {
329
330 if (!(sl->mode & SL_MODE_CSLIP)) {
331 printk(KERN_WARNING "%s: compressed packet ignored\n", dev->name);
332 return;
333 }
334
335
336 if (count + 80 > sl->buffsize) {
337 dev->stats.rx_over_errors++;
338 return;
339 }
340 count = slhc_uncompress(sl->slcomp, sl->rbuff, count);
341 if (count <= 0)
342 return;
343 } else if (c >= SL_TYPE_UNCOMPRESSED_TCP) {
344 if (!(sl->mode & SL_MODE_CSLIP)) {
345
346 sl->mode |= SL_MODE_CSLIP;
347 sl->mode &= ~SL_MODE_ADAPTIVE;
348 printk(KERN_INFO "%s: header compression turned on\n", dev->name);
349 }
350 sl->rbuff[0] &= 0x4f;
351 if (slhc_remember(sl->slcomp, sl->rbuff, count) <= 0)
352 return;
353 }
354 }
355#endif
356
357 dev->stats.rx_bytes += count;
358
359 skb = dev_alloc_skb(count);
360 if (skb == NULL) {
361 printk(KERN_WARNING "%s: memory squeeze, dropping packet.\n", dev->name);
362 dev->stats.rx_dropped++;
363 return;
364 }
365 skb->dev = dev;
366 memcpy(skb_put(skb, count), sl->rbuff, count);
367 skb_reset_mac_header(skb);
368 skb->protocol = htons(ETH_P_IP);
369 netif_rx_ni(skb);
370 dev->stats.rx_packets++;
371}
372
373
374static void sl_encaps(struct slip *sl, unsigned char *icp, int len)
375{
376 unsigned char *p;
377 int actual, count;
378
379 if (len > sl->mtu) {
380 printk(KERN_WARNING "%s: truncating oversized transmit packet!\n", sl->dev->name);
381 sl->dev->stats.tx_dropped++;
382 sl_unlock(sl);
383 return;
384 }
385
386 p = icp;
387#ifdef SL_INCLUDE_CSLIP
388 if (sl->mode & SL_MODE_CSLIP)
389 len = slhc_compress(sl->slcomp, p, len, sl->cbuff, &p, 1);
390#endif
391#ifdef CONFIG_SLIP_MODE_SLIP6
392 if (sl->mode & SL_MODE_SLIP6)
393 count = slip_esc6(p, sl->xbuff, len);
394 else
395#endif
396 count = slip_esc(p, sl->xbuff, len);
397
398
399
400
401
402
403
404
405
406 set_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags);
407 actual = sl->tty->ops->write(sl->tty, sl->xbuff, count);
408#ifdef SL_CHECK_TRANSMIT
409 sl->dev->trans_start = jiffies;
410#endif
411 sl->xleft = count - actual;
412 sl->xhead = sl->xbuff + actual;
413#ifdef CONFIG_SLIP_SMART
414
415 clear_bit(SLF_OUTWAIT, &sl->flags);
416#endif
417}
418
419
420
421
422
423static void slip_write_wakeup(struct tty_struct *tty)
424{
425 int actual;
426 struct slip *sl = tty->disc_data;
427
428
429 if (!sl || sl->magic != SLIP_MAGIC || !netif_running(sl->dev))
430 return;
431
432 spin_lock(&sl->lock);
433 if (sl->xleft <= 0) {
434
435
436 sl->dev->stats.tx_packets++;
437 clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
438 spin_unlock(&sl->lock);
439 sl_unlock(sl);
440 return;
441 }
442
443 actual = tty->ops->write(tty, sl->xhead, sl->xleft);
444 sl->xleft -= actual;
445 sl->xhead += actual;
446 spin_unlock(&sl->lock);
447}
448
449static void sl_tx_timeout(struct net_device *dev)
450{
451 struct slip *sl = netdev_priv(dev);
452
453 spin_lock(&sl->lock);
454
455 if (netif_queue_stopped(dev)) {
456 if (!netif_running(dev))
457 goto out;
458
459
460
461
462#ifdef SL_CHECK_TRANSMIT
463 if (time_before(jiffies, dev_trans_start(dev) + 20 * HZ)) {
464
465 goto out;
466 }
467 printk(KERN_WARNING "%s: transmit timed out, %s?\n",
468 dev->name,
469 (tty_chars_in_buffer(sl->tty) || sl->xleft) ?
470 "bad line quality" : "driver error");
471 sl->xleft = 0;
472 clear_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags);
473 sl_unlock(sl);
474#endif
475 }
476out:
477 spin_unlock(&sl->lock);
478}
479
480
481
482static netdev_tx_t
483sl_xmit(struct sk_buff *skb, struct net_device *dev)
484{
485 struct slip *sl = netdev_priv(dev);
486
487 spin_lock(&sl->lock);
488 if (!netif_running(dev)) {
489 spin_unlock(&sl->lock);
490 printk(KERN_WARNING "%s: xmit call when iface is down\n", dev->name);
491 dev_kfree_skb(skb);
492 return NETDEV_TX_OK;
493 }
494 if (sl->tty == NULL) {
495 spin_unlock(&sl->lock);
496 dev_kfree_skb(skb);
497 return NETDEV_TX_OK;
498 }
499
500 sl_lock(sl);
501 dev->stats.tx_bytes += skb->len;
502 sl_encaps(sl, skb->data, skb->len);
503 spin_unlock(&sl->lock);
504
505 dev_kfree_skb(skb);
506 return NETDEV_TX_OK;
507}
508
509
510
511
512
513
514
515
516static int
517sl_close(struct net_device *dev)
518{
519 struct slip *sl = netdev_priv(dev);
520
521 spin_lock_bh(&sl->lock);
522 if (sl->tty)
523
524 clear_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags);
525 netif_stop_queue(dev);
526 sl->rcount = 0;
527 sl->xleft = 0;
528 spin_unlock_bh(&sl->lock);
529
530 return 0;
531}
532
533
534
535static int sl_open(struct net_device *dev)
536{
537 struct slip *sl = netdev_priv(dev);
538
539 if (sl->tty == NULL)
540 return -ENODEV;
541
542 sl->flags &= (1 << SLF_INUSE);
543 netif_start_queue(dev);
544 return 0;
545}
546
547
548
549static int sl_change_mtu(struct net_device *dev, int new_mtu)
550{
551 struct slip *sl = netdev_priv(dev);
552
553 if (new_mtu < 68 || new_mtu > 65534)
554 return -EINVAL;
555
556 if (new_mtu != dev->mtu)
557 return sl_realloc_bufs(sl, new_mtu);
558 return 0;
559}
560
561
562
563static struct rtnl_link_stats64 *
564sl_get_stats64(struct net_device *dev, struct rtnl_link_stats64 *stats)
565{
566 struct net_device_stats *devstats = &dev->stats;
567#ifdef SL_INCLUDE_CSLIP
568 struct slip *sl = netdev_priv(dev);
569 struct slcompress *comp = sl->slcomp;
570#endif
571 stats->rx_packets = devstats->rx_packets;
572 stats->tx_packets = devstats->tx_packets;
573 stats->rx_bytes = devstats->rx_bytes;
574 stats->tx_bytes = devstats->tx_bytes;
575 stats->rx_dropped = devstats->rx_dropped;
576 stats->tx_dropped = devstats->tx_dropped;
577 stats->tx_errors = devstats->tx_errors;
578 stats->rx_errors = devstats->rx_errors;
579 stats->rx_over_errors = devstats->rx_over_errors;
580
581#ifdef SL_INCLUDE_CSLIP
582 if (comp) {
583
584 stats->rx_compressed = comp->sls_i_compressed;
585 stats->tx_compressed = comp->sls_o_compressed;
586
587
588 stats->rx_fifo_errors += comp->sls_i_compressed;
589 stats->rx_dropped += comp->sls_i_tossed;
590 stats->tx_fifo_errors += comp->sls_o_compressed;
591 stats->collisions += comp->sls_o_misses;
592 }
593#endif
594 return stats;
595}
596
597
598
599static int sl_init(struct net_device *dev)
600{
601 struct slip *sl = netdev_priv(dev);
602
603
604
605
606
607 dev->mtu = sl->mtu;
608 dev->type = ARPHRD_SLIP + sl->mode;
609#ifdef SL_CHECK_TRANSMIT
610 dev->watchdog_timeo = 20*HZ;
611#endif
612 return 0;
613}
614
615
616static void sl_uninit(struct net_device *dev)
617{
618 struct slip *sl = netdev_priv(dev);
619
620 sl_free_bufs(sl);
621}
622
623
624static void sl_free_netdev(struct net_device *dev)
625{
626 int i = dev->base_addr;
627 free_netdev(dev);
628 slip_devs[i] = NULL;
629}
630
631static const struct net_device_ops sl_netdev_ops = {
632 .ndo_init = sl_init,
633 .ndo_uninit = sl_uninit,
634 .ndo_open = sl_open,
635 .ndo_stop = sl_close,
636 .ndo_start_xmit = sl_xmit,
637 .ndo_get_stats64 = sl_get_stats64,
638 .ndo_change_mtu = sl_change_mtu,
639 .ndo_tx_timeout = sl_tx_timeout,
640#ifdef CONFIG_SLIP_SMART
641 .ndo_do_ioctl = sl_ioctl,
642#endif
643};
644
645
646static void sl_setup(struct net_device *dev)
647{
648 dev->netdev_ops = &sl_netdev_ops;
649 dev->destructor = sl_free_netdev;
650
651 dev->hard_header_len = 0;
652 dev->addr_len = 0;
653 dev->tx_queue_len = 10;
654
655
656 dev->flags = IFF_NOARP|IFF_POINTOPOINT|IFF_MULTICAST;
657}
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673static void slip_receive_buf(struct tty_struct *tty, const unsigned char *cp,
674 char *fp, int count)
675{
676 struct slip *sl = tty->disc_data;
677
678 if (!sl || sl->magic != SLIP_MAGIC || !netif_running(sl->dev))
679 return;
680
681
682 while (count--) {
683 if (fp && *fp++) {
684 if (!test_and_set_bit(SLF_ERROR, &sl->flags))
685 sl->dev->stats.rx_errors++;
686 cp++;
687 continue;
688 }
689#ifdef CONFIG_SLIP_MODE_SLIP6
690 if (sl->mode & SL_MODE_SLIP6)
691 slip_unesc6(sl, *cp++);
692 else
693#endif
694 slip_unesc(sl, *cp++);
695 }
696}
697
698
699
700
701
702
703static void sl_sync(void)
704{
705 int i;
706 struct net_device *dev;
707 struct slip *sl;
708
709 for (i = 0; i < slip_maxdev; i++) {
710 dev = slip_devs[i];
711 if (dev == NULL)
712 break;
713
714 sl = netdev_priv(dev);
715 if (sl->tty || sl->leased)
716 continue;
717 if (dev->flags & IFF_UP)
718 dev_close(dev);
719 }
720}
721
722
723
724static struct slip *sl_alloc(dev_t line)
725{
726 int i;
727 char name[IFNAMSIZ];
728 struct net_device *dev = NULL;
729 struct slip *sl;
730
731 for (i = 0; i < slip_maxdev; i++) {
732 dev = slip_devs[i];
733 if (dev == NULL)
734 break;
735 }
736
737 if (i >= slip_maxdev)
738 return NULL;
739
740 sprintf(name, "sl%d", i);
741 dev = alloc_netdev(sizeof(*sl), name, sl_setup);
742 if (!dev)
743 return NULL;
744
745 dev->base_addr = i;
746 sl = netdev_priv(dev);
747
748
749 sl->magic = SLIP_MAGIC;
750 sl->dev = dev;
751 spin_lock_init(&sl->lock);
752 sl->mode = SL_MODE_DEFAULT;
753#ifdef CONFIG_SLIP_SMART
754
755 init_timer(&sl->keepalive_timer);
756 sl->keepalive_timer.data = (unsigned long)sl;
757 sl->keepalive_timer.function = sl_keepalive;
758 init_timer(&sl->outfill_timer);
759 sl->outfill_timer.data = (unsigned long)sl;
760 sl->outfill_timer.function = sl_outfill;
761#endif
762 slip_devs[i] = dev;
763 return sl;
764}
765
766
767
768
769
770
771
772
773
774
775
776static int slip_open(struct tty_struct *tty)
777{
778 struct slip *sl;
779 int err;
780
781 if (!capable(CAP_NET_ADMIN))
782 return -EPERM;
783
784 if (tty->ops->write == NULL)
785 return -EOPNOTSUPP;
786
787
788
789
790
791 rtnl_lock();
792
793
794 sl_sync();
795
796 sl = tty->disc_data;
797
798 err = -EEXIST;
799
800 if (sl && sl->magic == SLIP_MAGIC)
801 goto err_exit;
802
803
804 err = -ENFILE;
805 sl = sl_alloc(tty_devnum(tty));
806 if (sl == NULL)
807 goto err_exit;
808
809 sl->tty = tty;
810 tty->disc_data = sl;
811 sl->pid = current->pid;
812
813 if (!test_bit(SLF_INUSE, &sl->flags)) {
814
815 err = sl_alloc_bufs(sl, SL_MTU);
816 if (err)
817 goto err_free_chan;
818
819 set_bit(SLF_INUSE, &sl->flags);
820
821 err = register_netdevice(sl->dev);
822 if (err)
823 goto err_free_bufs;
824 }
825
826#ifdef CONFIG_SLIP_SMART
827 if (sl->keepalive) {
828 sl->keepalive_timer.expires = jiffies + sl->keepalive * HZ;
829 add_timer(&sl->keepalive_timer);
830 }
831 if (sl->outfill) {
832 sl->outfill_timer.expires = jiffies + sl->outfill * HZ;
833 add_timer(&sl->outfill_timer);
834 }
835#endif
836
837
838 rtnl_unlock();
839 tty->receive_room = 65536;
840
841
842 return 0;
843
844err_free_bufs:
845 sl_free_bufs(sl);
846
847err_free_chan:
848 sl->tty = NULL;
849 tty->disc_data = NULL;
850 clear_bit(SLF_INUSE, &sl->flags);
851
852err_exit:
853 rtnl_unlock();
854
855
856 return err;
857}
858
859
860
861
862
863
864
865
866
867static void slip_close(struct tty_struct *tty)
868{
869 struct slip *sl = tty->disc_data;
870
871
872 if (!sl || sl->magic != SLIP_MAGIC || sl->tty != tty)
873 return;
874
875 tty->disc_data = NULL;
876 sl->tty = NULL;
877
878
879#ifdef CONFIG_SLIP_SMART
880 del_timer_sync(&sl->keepalive_timer);
881 del_timer_sync(&sl->outfill_timer);
882#endif
883
884 unregister_netdev(sl->dev);
885
886}
887
888static int slip_hangup(struct tty_struct *tty)
889{
890 slip_close(tty);
891 return 0;
892}
893
894
895
896
897static int slip_esc(unsigned char *s, unsigned char *d, int len)
898{
899 unsigned char *ptr = d;
900 unsigned char c;
901
902
903
904
905
906
907
908 *ptr++ = END;
909
910
911
912
913
914
915 while (len-- > 0) {
916 switch (c = *s++) {
917 case END:
918 *ptr++ = ESC;
919 *ptr++ = ESC_END;
920 break;
921 case ESC:
922 *ptr++ = ESC;
923 *ptr++ = ESC_ESC;
924 break;
925 default:
926 *ptr++ = c;
927 break;
928 }
929 }
930 *ptr++ = END;
931 return ptr - d;
932}
933
934static void slip_unesc(struct slip *sl, unsigned char s)
935{
936
937 switch (s) {
938 case END:
939#ifdef CONFIG_SLIP_SMART
940
941 if (test_bit(SLF_KEEPTEST, &sl->flags))
942 clear_bit(SLF_KEEPTEST, &sl->flags);
943#endif
944
945 if (!test_and_clear_bit(SLF_ERROR, &sl->flags) &&
946 (sl->rcount > 2))
947 sl_bump(sl);
948 clear_bit(SLF_ESCAPE, &sl->flags);
949 sl->rcount = 0;
950 return;
951
952 case ESC:
953 set_bit(SLF_ESCAPE, &sl->flags);
954 return;
955 case ESC_ESC:
956 if (test_and_clear_bit(SLF_ESCAPE, &sl->flags))
957 s = ESC;
958 break;
959 case ESC_END:
960 if (test_and_clear_bit(SLF_ESCAPE, &sl->flags))
961 s = END;
962 break;
963 }
964 if (!test_bit(SLF_ERROR, &sl->flags)) {
965 if (sl->rcount < sl->buffsize) {
966 sl->rbuff[sl->rcount++] = s;
967 return;
968 }
969 sl->dev->stats.rx_over_errors++;
970 set_bit(SLF_ERROR, &sl->flags);
971 }
972}
973
974
975#ifdef CONFIG_SLIP_MODE_SLIP6
976
977
978
979
980static int slip_esc6(unsigned char *s, unsigned char *d, int len)
981{
982 unsigned char *ptr = d;
983 unsigned char c;
984 int i;
985 unsigned short v = 0;
986 short bits = 0;
987
988
989
990
991
992
993
994 *ptr++ = 0x70;
995
996
997
998
999
1000 for (i = 0; i < len; ++i) {
1001 v = (v << 8) | s[i];
1002 bits += 8;
1003 while (bits >= 6) {
1004 bits -= 6;
1005 c = 0x30 + ((v >> bits) & 0x3F);
1006 *ptr++ = c;
1007 }
1008 }
1009 if (bits) {
1010 c = 0x30 + ((v << (6 - bits)) & 0x3F);
1011 *ptr++ = c;
1012 }
1013 *ptr++ = 0x70;
1014 return ptr - d;
1015}
1016
1017static void slip_unesc6(struct slip *sl, unsigned char s)
1018{
1019 unsigned char c;
1020
1021 if (s == 0x70) {
1022#ifdef CONFIG_SLIP_SMART
1023
1024 if (test_bit(SLF_KEEPTEST, &sl->flags))
1025 clear_bit(SLF_KEEPTEST, &sl->flags);
1026#endif
1027
1028 if (!test_and_clear_bit(SLF_ERROR, &sl->flags) &&
1029 (sl->rcount > 2))
1030 sl_bump(sl);
1031 sl->rcount = 0;
1032 sl->xbits = 0;
1033 sl->xdata = 0;
1034 } else if (s >= 0x30 && s < 0x70) {
1035 sl->xdata = (sl->xdata << 6) | ((s - 0x30) & 0x3F);
1036 sl->xbits += 6;
1037 if (sl->xbits >= 8) {
1038 sl->xbits -= 8;
1039 c = (unsigned char)(sl->xdata >> sl->xbits);
1040 if (!test_bit(SLF_ERROR, &sl->flags)) {
1041 if (sl->rcount < sl->buffsize) {
1042 sl->rbuff[sl->rcount++] = c;
1043 return;
1044 }
1045 sl->dev->stats.rx_over_errors++;
1046 set_bit(SLF_ERROR, &sl->flags);
1047 }
1048 }
1049 }
1050}
1051#endif
1052
1053
1054static int slip_ioctl(struct tty_struct *tty, struct file *file,
1055 unsigned int cmd, unsigned long arg)
1056{
1057 struct slip *sl = tty->disc_data;
1058 unsigned int tmp;
1059 int __user *p = (int __user *)arg;
1060
1061
1062 if (!sl || sl->magic != SLIP_MAGIC)
1063 return -EINVAL;
1064
1065 switch (cmd) {
1066 case SIOCGIFNAME:
1067 tmp = strlen(sl->dev->name) + 1;
1068 if (copy_to_user((void __user *)arg, sl->dev->name, tmp))
1069 return -EFAULT;
1070 return 0;
1071
1072 case SIOCGIFENCAP:
1073 if (put_user(sl->mode, p))
1074 return -EFAULT;
1075 return 0;
1076
1077 case SIOCSIFENCAP:
1078 if (get_user(tmp, p))
1079 return -EFAULT;
1080#ifndef SL_INCLUDE_CSLIP
1081 if (tmp & (SL_MODE_CSLIP|SL_MODE_ADAPTIVE))
1082 return -EINVAL;
1083#else
1084 if ((tmp & (SL_MODE_ADAPTIVE | SL_MODE_CSLIP)) ==
1085 (SL_MODE_ADAPTIVE | SL_MODE_CSLIP))
1086
1087 tmp &= ~SL_MODE_ADAPTIVE;
1088#endif
1089#ifndef CONFIG_SLIP_MODE_SLIP6
1090 if (tmp & SL_MODE_SLIP6)
1091 return -EINVAL;
1092#endif
1093 sl->mode = tmp;
1094 sl->dev->type = ARPHRD_SLIP + sl->mode;
1095 return 0;
1096
1097 case SIOCSIFHWADDR:
1098 return -EINVAL;
1099
1100#ifdef CONFIG_SLIP_SMART
1101
1102 case SIOCSKEEPALIVE:
1103 if (get_user(tmp, p))
1104 return -EFAULT;
1105 if (tmp > 255)
1106 return -EINVAL;
1107
1108 spin_lock_bh(&sl->lock);
1109 if (!sl->tty) {
1110 spin_unlock_bh(&sl->lock);
1111 return -ENODEV;
1112 }
1113 sl->keepalive = (u8)tmp;
1114 if (sl->keepalive != 0) {
1115 mod_timer(&sl->keepalive_timer,
1116 jiffies + sl->keepalive * HZ);
1117 set_bit(SLF_KEEPTEST, &sl->flags);
1118 } else
1119 del_timer(&sl->keepalive_timer);
1120 spin_unlock_bh(&sl->lock);
1121 return 0;
1122
1123 case SIOCGKEEPALIVE:
1124 if (put_user(sl->keepalive, p))
1125 return -EFAULT;
1126 return 0;
1127
1128 case SIOCSOUTFILL:
1129 if (get_user(tmp, p))
1130 return -EFAULT;
1131 if (tmp > 255)
1132 return -EINVAL;
1133 spin_lock_bh(&sl->lock);
1134 if (!sl->tty) {
1135 spin_unlock_bh(&sl->lock);
1136 return -ENODEV;
1137 }
1138 sl->outfill = (u8)tmp;
1139 if (sl->outfill != 0) {
1140 mod_timer(&sl->outfill_timer,
1141 jiffies + sl->outfill * HZ);
1142 set_bit(SLF_OUTWAIT, &sl->flags);
1143 } else
1144 del_timer(&sl->outfill_timer);
1145 spin_unlock_bh(&sl->lock);
1146 return 0;
1147
1148 case SIOCGOUTFILL:
1149 if (put_user(sl->outfill, p))
1150 return -EFAULT;
1151 return 0;
1152
1153#endif
1154 default:
1155 return tty_mode_ioctl(tty, file, cmd, arg);
1156 }
1157}
1158
1159#ifdef CONFIG_COMPAT
1160static long slip_compat_ioctl(struct tty_struct *tty, struct file *file,
1161 unsigned int cmd, unsigned long arg)
1162{
1163 switch (cmd) {
1164 case SIOCGIFNAME:
1165 case SIOCGIFENCAP:
1166 case SIOCSIFENCAP:
1167 case SIOCSIFHWADDR:
1168 case SIOCSKEEPALIVE:
1169 case SIOCGKEEPALIVE:
1170 case SIOCSOUTFILL:
1171 case SIOCGOUTFILL:
1172 return slip_ioctl(tty, file, cmd,
1173 (unsigned long)compat_ptr(arg));
1174 }
1175
1176 return -ENOIOCTLCMD;
1177}
1178#endif
1179
1180
1181#ifdef CONFIG_SLIP_SMART
1182
1183
1184
1185
1186static int sl_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
1187{
1188 struct slip *sl = netdev_priv(dev);
1189 unsigned long *p = (unsigned long *)&rq->ifr_ifru;
1190
1191 if (sl == NULL)
1192 return -ENODEV;
1193
1194 spin_lock_bh(&sl->lock);
1195
1196 if (!sl->tty) {
1197 spin_unlock_bh(&sl->lock);
1198 return -ENODEV;
1199 }
1200
1201 switch (cmd) {
1202 case SIOCSKEEPALIVE:
1203
1204 if ((unsigned)*p > 255) {
1205 spin_unlock_bh(&sl->lock);
1206 return -EINVAL;
1207 }
1208 sl->keepalive = (u8)*p;
1209 if (sl->keepalive != 0) {
1210 sl->keepalive_timer.expires =
1211 jiffies + sl->keepalive * HZ;
1212 mod_timer(&sl->keepalive_timer,
1213 jiffies + sl->keepalive * HZ);
1214 set_bit(SLF_KEEPTEST, &sl->flags);
1215 } else
1216 del_timer(&sl->keepalive_timer);
1217 break;
1218
1219 case SIOCGKEEPALIVE:
1220 *p = sl->keepalive;
1221 break;
1222
1223 case SIOCSOUTFILL:
1224 if ((unsigned)*p > 255) {
1225 spin_unlock_bh(&sl->lock);
1226 return -EINVAL;
1227 }
1228 sl->outfill = (u8)*p;
1229 if (sl->outfill != 0) {
1230 mod_timer(&sl->outfill_timer,
1231 jiffies + sl->outfill * HZ);
1232 set_bit(SLF_OUTWAIT, &sl->flags);
1233 } else
1234 del_timer(&sl->outfill_timer);
1235 break;
1236
1237 case SIOCGOUTFILL:
1238 *p = sl->outfill;
1239 break;
1240
1241 case SIOCSLEASE:
1242
1243
1244
1245 if (sl->tty != current->signal->tty &&
1246 sl->pid != current->pid) {
1247 spin_unlock_bh(&sl->lock);
1248 return -EPERM;
1249 }
1250 sl->leased = 0;
1251 if (*p)
1252 sl->leased = 1;
1253 break;
1254
1255 case SIOCGLEASE:
1256 *p = sl->leased;
1257 }
1258 spin_unlock_bh(&sl->lock);
1259 return 0;
1260}
1261#endif
1262
1263
1264static struct tty_ldisc_ops sl_ldisc = {
1265 .owner = THIS_MODULE,
1266 .magic = TTY_LDISC_MAGIC,
1267 .name = "slip",
1268 .open = slip_open,
1269 .close = slip_close,
1270 .hangup = slip_hangup,
1271 .ioctl = slip_ioctl,
1272#ifdef CONFIG_COMPAT
1273 .compat_ioctl = slip_compat_ioctl,
1274#endif
1275 .receive_buf = slip_receive_buf,
1276 .write_wakeup = slip_write_wakeup,
1277};
1278
1279static int __init slip_init(void)
1280{
1281 int status;
1282
1283 if (slip_maxdev < 4)
1284 slip_maxdev = 4;
1285
1286 printk(KERN_INFO "SLIP: version %s (dynamic channels, max=%d)"
1287#ifdef CONFIG_SLIP_MODE_SLIP6
1288 " (6 bit encapsulation enabled)"
1289#endif
1290 ".\n",
1291 SLIP_VERSION, slip_maxdev);
1292#if defined(SL_INCLUDE_CSLIP)
1293 printk(KERN_INFO "CSLIP: code copyright 1989 Regents of the University of California.\n");
1294#endif
1295#ifdef CONFIG_SLIP_SMART
1296 printk(KERN_INFO "SLIP linefill/keepalive option.\n");
1297#endif
1298
1299 slip_devs = kzalloc(sizeof(struct net_device *)*slip_maxdev,
1300 GFP_KERNEL);
1301 if (!slip_devs)
1302 return -ENOMEM;
1303
1304
1305 status = tty_register_ldisc(N_SLIP, &sl_ldisc);
1306 if (status != 0) {
1307 printk(KERN_ERR "SLIP: can't register line discipline (err = %d)\n", status);
1308 kfree(slip_devs);
1309 }
1310 return status;
1311}
1312
1313static void __exit slip_exit(void)
1314{
1315 int i;
1316 struct net_device *dev;
1317 struct slip *sl;
1318 unsigned long timeout = jiffies + HZ;
1319 int busy = 0;
1320
1321 if (slip_devs == NULL)
1322 return;
1323
1324
1325
1326 do {
1327 if (busy)
1328 msleep_interruptible(100);
1329
1330 busy = 0;
1331 for (i = 0; i < slip_maxdev; i++) {
1332 dev = slip_devs[i];
1333 if (!dev)
1334 continue;
1335 sl = netdev_priv(dev);
1336 spin_lock_bh(&sl->lock);
1337 if (sl->tty) {
1338 busy++;
1339 tty_hangup(sl->tty);
1340 }
1341 spin_unlock_bh(&sl->lock);
1342 }
1343 } while (busy && time_before(jiffies, timeout));
1344
1345
1346
1347
1348 for (i = 0; i < slip_maxdev; i++) {
1349 dev = slip_devs[i];
1350 if (!dev)
1351 continue;
1352 slip_devs[i] = NULL;
1353
1354 sl = netdev_priv(dev);
1355 if (sl->tty) {
1356 printk(KERN_ERR "%s: tty discipline still running\n",
1357 dev->name);
1358
1359 dev->destructor = NULL;
1360 }
1361
1362 unregister_netdev(dev);
1363 }
1364
1365 kfree(slip_devs);
1366 slip_devs = NULL;
1367
1368 i = tty_unregister_ldisc(N_SLIP);
1369 if (i != 0)
1370 printk(KERN_ERR "SLIP: can't unregister line discipline (err = %d)\n", i);
1371}
1372
1373module_init(slip_init);
1374module_exit(slip_exit);
1375
1376#ifdef CONFIG_SLIP_SMART
1377
1378
1379
1380
1381
1382static void sl_outfill(unsigned long sls)
1383{
1384 struct slip *sl = (struct slip *)sls;
1385
1386 spin_lock(&sl->lock);
1387
1388 if (sl->tty == NULL)
1389 goto out;
1390
1391 if (sl->outfill) {
1392 if (test_bit(SLF_OUTWAIT, &sl->flags)) {
1393
1394#ifdef CONFIG_SLIP_MODE_SLIP6
1395 unsigned char s = (sl->mode & SL_MODE_SLIP6)?0x70:END;
1396#else
1397 unsigned char s = END;
1398#endif
1399
1400 if (!netif_queue_stopped(sl->dev)) {
1401
1402 sl->tty->ops->write(sl->tty, &s, 1);
1403 }
1404 } else
1405 set_bit(SLF_OUTWAIT, &sl->flags);
1406
1407 mod_timer(&sl->outfill_timer, jiffies+sl->outfill*HZ);
1408 }
1409out:
1410 spin_unlock(&sl->lock);
1411}
1412
1413static void sl_keepalive(unsigned long sls)
1414{
1415 struct slip *sl = (struct slip *)sls;
1416
1417 spin_lock(&sl->lock);
1418
1419 if (sl->tty == NULL)
1420 goto out;
1421
1422 if (sl->keepalive) {
1423 if (test_bit(SLF_KEEPTEST, &sl->flags)) {
1424
1425 if (sl->outfill)
1426
1427 (void)del_timer(&sl->outfill_timer);
1428 printk(KERN_DEBUG "%s: no packets received during keepalive timeout, hangup.\n", sl->dev->name);
1429
1430 tty_hangup(sl->tty);
1431
1432 goto out;
1433 } else
1434 set_bit(SLF_KEEPTEST, &sl->flags);
1435
1436 mod_timer(&sl->keepalive_timer, jiffies+sl->keepalive*HZ);
1437 }
1438out:
1439 spin_unlock(&sl->lock);
1440}
1441
1442#endif
1443MODULE_LICENSE("GPL");
1444MODULE_ALIAS_LDISC(N_SLIP);
1445