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[net-next-2.6.git] / drivers / net / ppp_generic.c
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1da177e4
LT		 1/*
2 * Generic PPP layer for Linux.
3 *
4 * Copyright 1999-2002 Paul Mackerras.
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 *
11 * The generic PPP layer handles the PPP network interfaces, the
12 * /dev/ppp device, packet and VJ compression, and multilink.
13 * It talks to PPP `channels' via the interface defined in
14 * include/linux/ppp_channel.h. Channels provide the basic means for
15 * sending and receiving PPP frames on some kind of communications
16 * channel.
17 *
18 * Part of the code in this driver was inspired by the old async-only
19 * PPP driver, written by Michael Callahan and Al Longyear, and
20 * subsequently hacked by Paul Mackerras.
21 *
22 * ==FILEVERSION 20041108==
23 */
24
25#include <linux/config.h>
26#include <linux/module.h>
27#include <linux/kernel.h>
28#include <linux/kmod.h>
29#include <linux/init.h>
30#include <linux/list.h>
31#include <linux/devfs_fs_kernel.h>
32#include <linux/netdevice.h>
33#include <linux/poll.h>
34#include <linux/ppp_defs.h>
35#include <linux/filter.h>
36#include <linux/if_ppp.h>
37#include <linux/ppp_channel.h>
38#include <linux/ppp-comp.h>
39#include <linux/skbuff.h>
40#include <linux/rtnetlink.h>
41#include <linux/if_arp.h>
42#include <linux/ip.h>
43#include <linux/tcp.h>
44#include <linux/spinlock.h>
45#include <linux/smp_lock.h>
46#include <linux/rwsem.h>
47#include <linux/stddef.h>
48#include <linux/device.h>
49#include <net/slhc_vj.h>
50#include <asm/atomic.h>
51
52#define PPP_VERSION "2.4.2"
53
54/*
55 * Network protocols we support.
56 */
57#define NP_IP 0 /* Internet Protocol V4 */
58#define NP_IPV6 1 /* Internet Protocol V6 */
59#define NP_IPX 2 /* IPX protocol */
60#define NP_AT 3 /* Appletalk protocol */
61#define NP_MPLS_UC 4 /* MPLS unicast */
62#define NP_MPLS_MC 5 /* MPLS multicast */
63#define NUM_NP 6 /* Number of NPs. */
64
65#define MPHDRLEN 6 /* multilink protocol header length */
66#define MPHDRLEN_SSN 4 /* ditto with short sequence numbers */
67#define MIN_FRAG_SIZE 64
68
69/*
70 * An instance of /dev/ppp can be associated with either a ppp
71 * interface unit or a ppp channel. In both cases, file->private_data
72 * points to one of these.
73 */
74struct ppp_file {
75 enum {
76 INTERFACE=1, CHANNEL
77 } kind;
78 struct sk_buff_head xq; /* pppd transmit queue */
79 struct sk_buff_head rq; /* receive queue for pppd */
80 wait_queue_head_t rwait; /* for poll on reading /dev/ppp */
81 atomic_t refcnt; /* # refs (incl /dev/ppp attached) */
82 int hdrlen; /* space to leave for headers */
83 int index; /* interface unit / channel number */
84 int dead; /* unit/channel has been shut down */
85};
86
87#define PF_TO_X(pf, X) ((X *)((char *)(pf) - offsetof(X, file)))
88
89#define PF_TO_PPP(pf) PF_TO_X(pf, struct ppp)
90#define PF_TO_CHANNEL(pf) PF_TO_X(pf, struct channel)
91
92#define ROUNDUP(n, x) (((n) + (x) - 1) / (x))
93
94/*
95 * Data structure describing one ppp unit.
96 * A ppp unit corresponds to a ppp network interface device
97 * and represents a multilink bundle.
98 * It can have 0 or more ppp channels connected to it.
99 */
100struct ppp {
101 struct ppp_file file; /* stuff for read/write/poll 0 */
102 struct file *owner; /* file that owns this unit 48 */
103 struct list_head channels; /* list of attached channels 4c */
104 int n_channels; /* how many channels are attached 54 */
105 spinlock_t rlock; /* lock for receive side 58 */
106 spinlock_t wlock; /* lock for transmit side 5c */
107 int mru; /* max receive unit 60 */
108 unsigned int flags; /* control bits 64 */
109 unsigned int xstate; /* transmit state bits 68 */
110 unsigned int rstate; /* receive state bits 6c */
111 int debug; /* debug flags 70 */
112 struct slcompress *vj; /* state for VJ header compression */
113 enum NPmode npmode[NUM_NP]; /* what to do with each net proto 78 */
114 struct sk_buff *xmit_pending; /* a packet ready to go out 88 */
115 struct compressor *xcomp; /* transmit packet compressor 8c */
116 void *xc_state; /* its internal state 90 */
117 struct compressor *rcomp; /* receive decompressor 94 */
118 void *rc_state; /* its internal state 98 */
119 unsigned long last_xmit; /* jiffies when last pkt sent 9c */
120 unsigned long last_recv; /* jiffies when last pkt rcvd a0 */
121 struct net_device *dev; /* network interface device a4 */
122#ifdef CONFIG_PPP_MULTILINK
123 int nxchan; /* next channel to send something on */
124 u32 nxseq; /* next sequence number to send */
125 int mrru; /* MP: max reconst. receive unit */
126 u32 nextseq; /* MP: seq no of next packet */
127 u32 minseq; /* MP: min of most recent seqnos */
128 struct sk_buff_head mrq; /* MP: receive reconstruction queue */
129#endif /* CONFIG_PPP_MULTILINK */
130 struct net_device_stats stats; /* statistics */
131#ifdef CONFIG_PPP_FILTER
132 struct sock_filter *pass_filter; /* filter for packets to pass */
133 struct sock_filter *active_filter;/* filter for pkts to reset idle */
134 unsigned pass_len, active_len;
135#endif /* CONFIG_PPP_FILTER */
136};
137
138/*
139 * Bits in flags: SC_NO_TCP_CCID, SC_CCP_OPEN, SC_CCP_UP, SC_LOOP_TRAFFIC,
140 * SC_MULTILINK, SC_MP_SHORTSEQ, SC_MP_XSHORTSEQ, SC_COMP_TCP, SC_REJ_COMP_TCP.
141 * Bits in rstate: SC_DECOMP_RUN, SC_DC_ERROR, SC_DC_FERROR.
142 * Bits in xstate: SC_COMP_RUN
143 */
144#define SC_FLAG_BITS (SC_NO_TCP_CCID|SC_CCP_OPEN|SC_CCP_UP|SC_LOOP_TRAFFIC \
145 |SC_MULTILINK|SC_MP_SHORTSEQ|SC_MP_XSHORTSEQ \
146 |SC_COMP_TCP|SC_REJ_COMP_TCP)
147
148/*
149 * Private data structure for each channel.
150 * This includes the data structure used for multilink.
151 */
152struct channel {
153 struct ppp_file file; /* stuff for read/write/poll */
154 struct list_head list; /* link in all/new_channels list */
155 struct ppp_channel *chan; /* public channel data structure */
156 struct rw_semaphore chan_sem; /* protects `chan' during chan ioctl */
157 spinlock_t downl; /* protects `chan', file.xq dequeue */
158 struct ppp *ppp; /* ppp unit we're connected to */
159 struct list_head clist; /* link in list of channels per unit */
160 rwlock_t upl; /* protects `ppp' */
161#ifdef CONFIG_PPP_MULTILINK
162 u8 avail; /* flag used in multilink stuff */
163 u8 had_frag; /* >= 1 fragments have been sent */
164 u32 lastseq; /* MP: last sequence # received */
165#endif /* CONFIG_PPP_MULTILINK */
166};
167
168/*
169 * SMP locking issues:
170 * Both the ppp.rlock and ppp.wlock locks protect the ppp.channels
171 * list and the ppp.n_channels field, you need to take both locks
172 * before you modify them.
173 * The lock ordering is: channel.upl -> ppp.wlock -> ppp.rlock ->
174 * channel.downl.
175 */
176
177/*
178 * A cardmap represents a mapping from unsigned integers to pointers,
179 * and provides a fast "find lowest unused number" operation.
180 * It uses a broad (32-way) tree with a bitmap at each level.
181 * It is designed to be space-efficient for small numbers of entries
182 * and time-efficient for large numbers of entries.
183 */
184#define CARDMAP_ORDER 5
185#define CARDMAP_WIDTH (1U << CARDMAP_ORDER)
186#define CARDMAP_MASK (CARDMAP_WIDTH - 1)
187
188struct cardmap {
189 int shift;
190 unsigned long inuse;
191 struct cardmap *parent;
192 void *ptr[CARDMAP_WIDTH];
193};
194static void *cardmap_get(struct cardmap *map, unsigned int nr);
195static void cardmap_set(struct cardmap **map, unsigned int nr, void *ptr);
196static unsigned int cardmap_find_first_free(struct cardmap *map);
197static void cardmap_destroy(struct cardmap **map);
198
199/*
200 * all_ppp_sem protects the all_ppp_units mapping.
201 * It also ensures that finding a ppp unit in the all_ppp_units map
202 * and updating its file.refcnt field is atomic.
203 */
204static DECLARE_MUTEX(all_ppp_sem);
205static struct cardmap *all_ppp_units;
206static atomic_t ppp_unit_count = ATOMIC_INIT(0);
207
208/*
209 * all_channels_lock protects all_channels and last_channel_index,
210 * and the atomicity of find a channel and updating its file.refcnt
211 * field.
212 */
213static DEFINE_SPINLOCK(all_channels_lock);
214static LIST_HEAD(all_channels);
215static LIST_HEAD(new_channels);
216static int last_channel_index;
217static atomic_t channel_count = ATOMIC_INIT(0);
218
219/* Get the PPP protocol number from a skb */
220#define PPP_PROTO(skb) (((skb)->data[0] << 8) + (skb)->data[1])
221
222/* We limit the length of ppp->file.rq to this (arbitrary) value */
223#define PPP_MAX_RQLEN 32
224
225/*
226 * Maximum number of multilink fragments queued up.
227 * This has to be large enough to cope with the maximum latency of
228 * the slowest channel relative to the others. Strictly it should
229 * depend on the number of channels and their characteristics.
230 */
231#define PPP_MP_MAX_QLEN 128
232
233/* Multilink header bits. */
234#define B 0x80 /* this fragment begins a packet */
235#define E 0x40 /* this fragment ends a packet */
236
237/* Compare multilink sequence numbers (assumed to be 32 bits wide) */
238#define seq_before(a, b) ((s32)((a) - (b)) < 0)
239#define seq_after(a, b) ((s32)((a) - (b)) > 0)
240
241/* Prototypes. */
242static int ppp_unattached_ioctl(struct ppp_file *pf, struct file *file,
243 unsigned int cmd, unsigned long arg);
244static void ppp_xmit_process(struct ppp *ppp);
245static void ppp_send_frame(struct ppp *ppp, struct sk_buff *skb);
246static void ppp_push(struct ppp *ppp);
247static void ppp_channel_push(struct channel *pch);
248static void ppp_receive_frame(struct ppp *ppp, struct sk_buff *skb,
249 struct channel *pch);
250static void ppp_receive_error(struct ppp *ppp);
251static void ppp_receive_nonmp_frame(struct ppp *ppp, struct sk_buff *skb);
252static struct sk_buff *ppp_decompress_frame(struct ppp *ppp,
253 struct sk_buff *skb);
254#ifdef CONFIG_PPP_MULTILINK
255static void ppp_receive_mp_frame(struct ppp *ppp, struct sk_buff *skb,
256 struct channel *pch);
257static void ppp_mp_insert(struct ppp *ppp, struct sk_buff *skb);
258static struct sk_buff *ppp_mp_reconstruct(struct ppp *ppp);
259static int ppp_mp_explode(struct ppp *ppp, struct sk_buff *skb);
260#endif /* CONFIG_PPP_MULTILINK */
261static int ppp_set_compress(struct ppp *ppp, unsigned long arg);
262static void ppp_ccp_peek(struct ppp *ppp, struct sk_buff *skb, int inbound);
263static void ppp_ccp_closed(struct ppp *ppp);
264static struct compressor *find_compressor(int type);
265static void ppp_get_stats(struct ppp *ppp, struct ppp_stats *st);
266static struct ppp *ppp_create_interface(int unit, int *retp);
267static void init_ppp_file(struct ppp_file *pf, int kind);
268static void ppp_shutdown_interface(struct ppp *ppp);
269static void ppp_destroy_interface(struct ppp *ppp);
270static struct ppp *ppp_find_unit(int unit);
271static struct channel *ppp_find_channel(int unit);
272static int ppp_connect_channel(struct channel *pch, int unit);
273static int ppp_disconnect_channel(struct channel *pch);
274static void ppp_destroy_channel(struct channel *pch);
275
56b22935 276static struct class *ppp_class;
1da177e4
LT		 277
278/* Translates a PPP protocol number to a NP index (NP == network protocol) */
279static inline int proto_to_npindex(int proto)
280{
281 switch (proto) {
282 case PPP_IP:
283 return NP_IP;
284 case PPP_IPV6:
285 return NP_IPV6;
286 case PPP_IPX:
287 return NP_IPX;
288 case PPP_AT:
289 return NP_AT;
290 case PPP_MPLS_UC:
291 return NP_MPLS_UC;
292 case PPP_MPLS_MC:
293 return NP_MPLS_MC;
294 }
295 return -EINVAL;
296}
297
298/* Translates an NP index into a PPP protocol number */
299static const int npindex_to_proto[NUM_NP] = {
300 PPP_IP,
301 PPP_IPV6,
302 PPP_IPX,
303 PPP_AT,
304 PPP_MPLS_UC,
305 PPP_MPLS_MC,
306};
307
308/* Translates an ethertype into an NP index */
309static inline int ethertype_to_npindex(int ethertype)
310{
311 switch (ethertype) {
312 case ETH_P_IP:
313 return NP_IP;
314 case ETH_P_IPV6:
315 return NP_IPV6;
316 case ETH_P_IPX:
317 return NP_IPX;
318 case ETH_P_PPPTALK:
319 case ETH_P_ATALK:
320 return NP_AT;
321 case ETH_P_MPLS_UC:
322 return NP_MPLS_UC;
323 case ETH_P_MPLS_MC:
324 return NP_MPLS_MC;
325 }
326 return -1;
327}
328
329/* Translates an NP index into an ethertype */
330static const int npindex_to_ethertype[NUM_NP] = {
331 ETH_P_IP,
332 ETH_P_IPV6,
333 ETH_P_IPX,
334 ETH_P_PPPTALK,
335 ETH_P_MPLS_UC,
336 ETH_P_MPLS_MC,
337};
338
339/*
340 * Locking shorthand.
341 */
342#define ppp_xmit_lock(ppp) spin_lock_bh(&(ppp)->wlock)
343#define ppp_xmit_unlock(ppp) spin_unlock_bh(&(ppp)->wlock)
344#define ppp_recv_lock(ppp) spin_lock_bh(&(ppp)->rlock)
345#define ppp_recv_unlock(ppp) spin_unlock_bh(&(ppp)->rlock)
346#define ppp_lock(ppp) do { ppp_xmit_lock(ppp); \
347 ppp_recv_lock(ppp); } while (0)
348#define ppp_unlock(ppp) do { ppp_recv_unlock(ppp); \
349 ppp_xmit_unlock(ppp); } while (0)
350
351/*
352 * /dev/ppp device routines.
353 * The /dev/ppp device is used by pppd to control the ppp unit.
354 * It supports the read, write, ioctl and poll functions.
355 * Open instances of /dev/ppp can be in one of three states:
356 * unattached, attached to a ppp unit, or attached to a ppp channel.
357 */
358static int ppp_open(struct inode *inode, struct file *file)
359{
360 /*
361 * This could (should?) be enforced by the permissions on /dev/ppp.
362 */
363 if (!capable(CAP_NET_ADMIN))
364 return -EPERM;
365 return 0;
366}
367
368static int ppp_release(struct inode *inode, struct file *file)
369{
370 struct ppp_file *pf = file->private_data;
371 struct ppp *ppp;
372
373 if (pf != 0) {
374 file->private_data = NULL;
375 if (pf->kind == INTERFACE) {
376 ppp = PF_TO_PPP(pf);
377 if (file == ppp->owner)
378 ppp_shutdown_interface(ppp);
379 }
380 if (atomic_dec_and_test(&pf->refcnt)) {
381 switch (pf->kind) {
382 case INTERFACE:
383 ppp_destroy_interface(PF_TO_PPP(pf));
384 break;
385 case CHANNEL:
386 ppp_destroy_channel(PF_TO_CHANNEL(pf));
387 break;
388 }
389 }
390 }
391 return 0;
392}
393
394static ssize_t ppp_read(struct file *file, char __user *buf,
395 size_t count, loff_t *ppos)
396{
397 struct ppp_file *pf = file->private_data;
398 DECLARE_WAITQUEUE(wait, current);
399 ssize_t ret;
400 struct sk_buff *skb = NULL;
401
402 ret = count;
403
404 if (pf == 0)
405 return -ENXIO;
406 add_wait_queue(&pf->rwait, &wait);
407 for (;;) {
408 set_current_state(TASK_INTERRUPTIBLE);
409 skb = skb_dequeue(&pf->rq);
410 if (skb)
411 break;
412 ret = 0;
413 if (pf->dead)
414 break;
415 if (pf->kind == INTERFACE) {
416 /*
417 * Return 0 (EOF) on an interface that has no
418 * channels connected, unless it is looping
419 * network traffic (demand mode).
420 */
421 struct ppp *ppp = PF_TO_PPP(pf);
422 if (ppp->n_channels == 0
423 && (ppp->flags & SC_LOOP_TRAFFIC) == 0)
424 break;
425 }
426 ret = -EAGAIN;
427 if (file->f_flags & O_NONBLOCK)
428 break;
429 ret = -ERESTARTSYS;
430 if (signal_pending(current))
431 break;
432 schedule();
433 }
434 set_current_state(TASK_RUNNING);
435 remove_wait_queue(&pf->rwait, &wait);
436
437 if (skb == 0)
438 goto out;
439
440 ret = -EOVERFLOW;
441 if (skb->len > count)
442 goto outf;
443 ret = -EFAULT;
444 if (copy_to_user(buf, skb->data, skb->len))
445 goto outf;
446 ret = skb->len;
447
448 outf:
449 kfree_skb(skb);
450 out:
451 return ret;
452}
453
454static ssize_t ppp_write(struct file *file, const char __user *buf,
455 size_t count, loff_t *ppos)
456{
457 struct ppp_file *pf = file->private_data;
458 struct sk_buff *skb;
459 ssize_t ret;
460
461 if (pf == 0)
462 return -ENXIO;
463 ret = -ENOMEM;
464 skb = alloc_skb(count + pf->hdrlen, GFP_KERNEL);
465 if (skb == 0)
466 goto out;
467 skb_reserve(skb, pf->hdrlen);
468 ret = -EFAULT;
469 if (copy_from_user(skb_put(skb, count), buf, count)) {
470 kfree_skb(skb);
471 goto out;
472 }
473
474 skb_queue_tail(&pf->xq, skb);
475
476 switch (pf->kind) {
477 case INTERFACE:
478 ppp_xmit_process(PF_TO_PPP(pf));
479 break;
480 case CHANNEL:
481 ppp_channel_push(PF_TO_CHANNEL(pf));
482 break;
483 }
484
485 ret = count;
486
487 out:
488 return ret;
489}
490
491/* No kernel lock - fine */
492static unsigned int ppp_poll(struct file *file, poll_table *wait)
493{
494 struct ppp_file *pf = file->private_data;
495 unsigned int mask;
496
497 if (pf == 0)
498 return 0;
499 poll_wait(file, &pf->rwait, wait);
500 mask = POLLOUT | POLLWRNORM;
501 if (skb_peek(&pf->rq) != 0)
502 mask |= POLLIN | POLLRDNORM;
503 if (pf->dead)
504 mask |= POLLHUP;
505 else if (pf->kind == INTERFACE) {
506 /* see comment in ppp_read */
507 struct ppp *ppp = PF_TO_PPP(pf);
508 if (ppp->n_channels == 0
509 && (ppp->flags & SC_LOOP_TRAFFIC) == 0)
510 mask |= POLLIN | POLLRDNORM;
511 }
512
513 return mask;
514}
515
516#ifdef CONFIG_PPP_FILTER
517static int get_filter(void __user *arg, struct sock_filter **p)
518{
519 struct sock_fprog uprog;
520 struct sock_filter *code = NULL;
521 int len, err;
522
523 if (copy_from_user(&uprog, arg, sizeof(uprog)))
524 return -EFAULT;
525
526 if (uprog.len > BPF_MAXINSNS)
527 return -EINVAL;
528
529 if (!uprog.len) {
530 *p = NULL;
531 return 0;
532 }
533
534 len = uprog.len * sizeof(struct sock_filter);
535 code = kmalloc(len, GFP_KERNEL);
536 if (code == NULL)
537 return -ENOMEM;
538
539 if (copy_from_user(code, uprog.filter, len)) {
540 kfree(code);
541 return -EFAULT;
542 }
543
544 err = sk_chk_filter(code, uprog.len);
545 if (err) {
546 kfree(code);
547 return err;
548 }
549
550 *p = code;
551 return uprog.len;
552}
553#endif /* CONFIG_PPP_FILTER */
554
555static int ppp_ioctl(struct inode *inode, struct file *file,
556 unsigned int cmd, unsigned long arg)
557{
558 struct ppp_file *pf = file->private_data;
559 struct ppp *ppp;
560 int err = -EFAULT, val, val2, i;
561 struct ppp_idle idle;
562 struct npioctl npi;
563 int unit, cflags;
564 struct slcompress *vj;
565 void __user *argp = (void __user *)arg;
566 int __user *p = argp;
567
568 if (pf == 0)
569 return ppp_unattached_ioctl(pf, file, cmd, arg);
570
571 if (cmd == PPPIOCDETACH) {
572 /*
573 * We have to be careful here... if the file descriptor
574 * has been dup'd, we could have another process in the
575 * middle of a poll using the same file *, so we had
576 * better not free the interface data structures -
577 * instead we fail the ioctl. Even in this case, we
578 * shut down the interface if we are the owner of it.
579 * Actually, we should get rid of PPPIOCDETACH, userland
580 * (i.e. pppd) could achieve the same effect by closing
581 * this fd and reopening /dev/ppp.
582 */
583 err = -EINVAL;
584 if (pf->kind == INTERFACE) {
585 ppp = PF_TO_PPP(pf);
586 if (file == ppp->owner)
587 ppp_shutdown_interface(ppp);
588 }
589 if (atomic_read(&file->f_count) <= 2) {
590 ppp_release(inode, file);
591 err = 0;
592 } else
593 printk(KERN_DEBUG "PPPIOCDETACH file->f_count=%d\n",
594 atomic_read(&file->f_count));
595 return err;
596 }
597
598 if (pf->kind == CHANNEL) {
599 struct channel *pch = PF_TO_CHANNEL(pf);
600 struct ppp_channel *chan;
601
602 switch (cmd) {
603 case PPPIOCCONNECT:
604 if (get_user(unit, p))
605 break;
606 err = ppp_connect_channel(pch, unit);
607 break;
608
609 case PPPIOCDISCONN:
610 err = ppp_disconnect_channel(pch);
611 break;
612
613 default:
614 down_read(&pch->chan_sem);
615 chan = pch->chan;
616 err = -ENOTTY;
617 if (chan && chan->ops->ioctl)
618 err = chan->ops->ioctl(chan, cmd, arg);
619 up_read(&pch->chan_sem);
620 }
621 return err;
622 }
623
624 if (pf->kind != INTERFACE) {
625 /* can't happen */
626 printk(KERN_ERR "PPP: not interface or channel??\n");
627 return -EINVAL;
628 }
629
630 ppp = PF_TO_PPP(pf);
631 switch (cmd) {
632 case PPPIOCSMRU:
633 if (get_user(val, p))
634 break;
635 ppp->mru = val;
636 err = 0;
637 break;
638
639 case PPPIOCSFLAGS:
640 if (get_user(val, p))
641 break;
642 ppp_lock(ppp);
643 cflags = ppp->flags & ~val;
644 ppp->flags = val & SC_FLAG_BITS;
645 ppp_unlock(ppp);
646 if (cflags & SC_CCP_OPEN)
647 ppp_ccp_closed(ppp);
648 err = 0;
649 break;
650
651 case PPPIOCGFLAGS:
652 val = ppp->flags | ppp->xstate | ppp->rstate;
653 if (put_user(val, p))
654 break;
655 err = 0;
656 break;
657
658 case PPPIOCSCOMPRESS:
659 err = ppp_set_compress(ppp, arg);
660 break;
661
662 case PPPIOCGUNIT:
663 if (put_user(ppp->file.index, p))
664 break;
665 err = 0;
666 break;
667
668 case PPPIOCSDEBUG:
669 if (get_user(val, p))
670 break;
671 ppp->debug = val;
672 err = 0;
673 break;
674
675 case PPPIOCGDEBUG:
676 if (put_user(ppp->debug, p))
677 break;
678 err = 0;
679 break;
680
681 case PPPIOCGIDLE:
682 idle.xmit_idle = (jiffies - ppp->last_xmit) / HZ;
683 idle.recv_idle = (jiffies - ppp->last_recv) / HZ;
684 if (copy_to_user(argp, &idle, sizeof(idle)))
685 break;
686 err = 0;
687 break;
688
689 case PPPIOCSMAXCID:
690 if (get_user(val, p))
691 break;
692 val2 = 15;
693 if ((val >> 16) != 0) {
694 val2 = val >> 16;
695 val &= 0xffff;
696 }
697 vj = slhc_init(val2+1, val+1);
698 if (vj == 0) {
699 printk(KERN_ERR "PPP: no memory (VJ compressor)\n");
700 err = -ENOMEM;
701 break;
702 }
703 ppp_lock(ppp);
704 if (ppp->vj != 0)
705 slhc_free(ppp->vj);
706 ppp->vj = vj;
707 ppp_unlock(ppp);
708 err = 0;
709 break;
710
711 case PPPIOCGNPMODE:
712 case PPPIOCSNPMODE:
713 if (copy_from_user(&npi, argp, sizeof(npi)))
714 break;
715 err = proto_to_npindex(npi.protocol);
716 if (err < 0)
717 break;
718 i = err;
719 if (cmd == PPPIOCGNPMODE) {
720 err = -EFAULT;
721 npi.mode = ppp->npmode[i];
722 if (copy_to_user(argp, &npi, sizeof(npi)))
723 break;
724 } else {
725 ppp->npmode[i] = npi.mode;
726 /* we may be able to transmit more packets now (??) */
727 netif_wake_queue(ppp->dev);
728 }
729 err = 0;
730 break;
731
732#ifdef CONFIG_PPP_FILTER
733 case PPPIOCSPASS:
734 {
735 struct sock_filter *code;
736 err = get_filter(argp, &code);
737 if (err >= 0) {
738 ppp_lock(ppp);
739 kfree(ppp->pass_filter);
740 ppp->pass_filter = code;
741 ppp->pass_len = err;
742 ppp_unlock(ppp);
743 err = 0;
744 }
745 break;
746 }
747 case PPPIOCSACTIVE:
748 {
749 struct sock_filter *code;
750 err = get_filter(argp, &code);
751 if (err >= 0) {
752 ppp_lock(ppp);
753 kfree(ppp->active_filter);
754 ppp->active_filter = code;
755 ppp->active_len = err;
756 ppp_unlock(ppp);
757 err = 0;
758 }
759 break;
760 }
761#endif /* CONFIG_PPP_FILTER */
762
763#ifdef CONFIG_PPP_MULTILINK
764 case PPPIOCSMRRU:
765 if (get_user(val, p))
766 break;
767 ppp_recv_lock(ppp);
768 ppp->mrru = val;
769 ppp_recv_unlock(ppp);
770 err = 0;
771 break;
772#endif /* CONFIG_PPP_MULTILINK */
773
774 default:
775 err = -ENOTTY;
776 }
777
778 return err;
779}
780
781static int ppp_unattached_ioctl(struct ppp_file *pf, struct file *file,
782 unsigned int cmd, unsigned long arg)
783{
784 int unit, err = -EFAULT;
785 struct ppp *ppp;
786 struct channel *chan;
787 int __user *p = (int __user *)arg;
788
789 switch (cmd) {
790 case PPPIOCNEWUNIT:
791 /* Create a new ppp unit */
792 if (get_user(unit, p))
793 break;
794 ppp = ppp_create_interface(unit, &err);
795 if (ppp == 0)
796 break;
797 file->private_data = &ppp->file;
798 ppp->owner = file;
799 err = -EFAULT;
800 if (put_user(ppp->file.index, p))
801 break;
802 err = 0;
803 break;
804
805 case PPPIOCATTACH:
806 /* Attach to an existing ppp unit */
807 if (get_user(unit, p))
808 break;
809 down(&all_ppp_sem);
810 err = -ENXIO;
811 ppp = ppp_find_unit(unit);
812 if (ppp != 0) {
813 atomic_inc(&ppp->file.refcnt);
814 file->private_data = &ppp->file;
815 err = 0;
816 }
817 up(&all_ppp_sem);
818 break;
819
820 case PPPIOCATTCHAN:
821 if (get_user(unit, p))
822 break;
823 spin_lock_bh(&all_channels_lock);
824 err = -ENXIO;
825 chan = ppp_find_channel(unit);
826 if (chan != 0) {
827 atomic_inc(&chan->file.refcnt);
828 file->private_data = &chan->file;
829 err = 0;
830 }
831 spin_unlock_bh(&all_channels_lock);
832 break;
833
834 default:
835 err = -ENOTTY;
836 }
837 return err;
838}
839
840static struct file_operations ppp_device_fops = {
841 .owner = THIS_MODULE,
842 .read = ppp_read,
843 .write = ppp_write,
844 .poll = ppp_poll,
845 .ioctl = ppp_ioctl,
846 .open = ppp_open,
847 .release = ppp_release
848};
849
850#define PPP_MAJOR 108
851
852/* Called at boot time if ppp is compiled into the kernel,
853 or at module load time (from init_module) if compiled as a module. */
854static int __init ppp_init(void)
855{
856 int err;
857
858 printk(KERN_INFO "PPP generic driver version " PPP_VERSION "\n");
859 err = register_chrdev(PPP_MAJOR, "ppp", &ppp_device_fops);
860 if (!err) {
56b22935 861 ppp_class = class_create(THIS_MODULE, "ppp");
1da177e4
LT		 862 if (IS_ERR(ppp_class)) {
863 err = PTR_ERR(ppp_class);
864 goto out_chrdev;
865 }
53f46542 866 class_device_create(ppp_class, NULL, MKDEV(PPP_MAJOR, 0), NULL, "ppp");
1da177e4
LT		 867 err = devfs_mk_cdev(MKDEV(PPP_MAJOR, 0),
868 S_IFCHR|S_IRUSR|S_IWUSR, "ppp");
869 if (err)
870 goto out_class;
871 }
872
873out:
874 if (err)
875 printk(KERN_ERR "failed to register PPP device (%d)\n", err);
876 return err;
877
878out_class:
56b22935
GKH		 879 class_device_destroy(ppp_class, MKDEV(PPP_MAJOR,0));
880 class_destroy(ppp_class);
1da177e4
LT		 881out_chrdev:
882 unregister_chrdev(PPP_MAJOR, "ppp");
883 goto out;
884}
885
886/*
887 * Network interface unit routines.
888 */
889static int
890ppp_start_xmit(struct sk_buff *skb, struct net_device *dev)
891{
892 struct ppp *ppp = (struct ppp *) dev->priv;
893 int npi, proto;
894 unsigned char *pp;
895
896 npi = ethertype_to_npindex(ntohs(skb->protocol));
897 if (npi < 0)
898 goto outf;
899
900 /* Drop, accept or reject the packet */
901 switch (ppp->npmode[npi]) {
902 case NPMODE_PASS:
903 break;
904 case NPMODE_QUEUE:
905 /* it would be nice to have a way to tell the network
906 system to queue this one up for later. */
907 goto outf;
908 case NPMODE_DROP:
909 case NPMODE_ERROR:
910 goto outf;
911 }
912
913 /* Put the 2-byte PPP protocol number on the front,
914 making sure there is room for the address and control fields. */
915 if (skb_headroom(skb) < PPP_HDRLEN) {
916 struct sk_buff *ns;
917
918 ns = alloc_skb(skb->len + dev->hard_header_len, GFP_ATOMIC);
919 if (ns == 0)
920 goto outf;
921 skb_reserve(ns, dev->hard_header_len);
922 skb_copy_bits(skb, 0, skb_put(ns, skb->len), skb->len);
923 kfree_skb(skb);
924 skb = ns;
925 }
926 pp = skb_push(skb, 2);
927 proto = npindex_to_proto[npi];
928 pp[0] = proto >> 8;
929 pp[1] = proto;
930
931 netif_stop_queue(dev);
932 skb_queue_tail(&ppp->file.xq, skb);
933 ppp_xmit_process(ppp);
934 return 0;
935
936 outf:
937 kfree_skb(skb);
938 ++ppp->stats.tx_dropped;
939 return 0;
940}
941
942static struct net_device_stats *
943ppp_net_stats(struct net_device *dev)
944{
945 struct ppp *ppp = (struct ppp *) dev->priv;
946
947 return &ppp->stats;
948}
949
950static int
951ppp_net_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
952{
953 struct ppp *ppp = dev->priv;
954 int err = -EFAULT;
955 void __user *addr = (void __user *) ifr->ifr_ifru.ifru_data;
956 struct ppp_stats stats;
957 struct ppp_comp_stats cstats;
958 char *vers;
959
960 switch (cmd) {
961 case SIOCGPPPSTATS:
962 ppp_get_stats(ppp, &stats);
963 if (copy_to_user(addr, &stats, sizeof(stats)))
964 break;
965 err = 0;
966 break;
967
968 case SIOCGPPPCSTATS:
969 memset(&cstats, 0, sizeof(cstats));
970 if (ppp->xc_state != 0)
971 ppp->xcomp->comp_stat(ppp->xc_state, &cstats.c);
972 if (ppp->rc_state != 0)
973 ppp->rcomp->decomp_stat(ppp->rc_state, &cstats.d);
974 if (copy_to_user(addr, &cstats, sizeof(cstats)))
975 break;
976 err = 0;
977 break;
978
979 case SIOCGPPPVER:
980 vers = PPP_VERSION;
981 if (copy_to_user(addr, vers, strlen(vers) + 1))
982 break;
983 err = 0;
984 break;
985
986 default:
987 err = -EINVAL;
988 }
989
990 return err;
991}
992
993static void ppp_setup(struct net_device *dev)
994{
995 dev->hard_header_len = PPP_HDRLEN;
996 dev->mtu = PPP_MTU;
997 dev->addr_len = 0;
998 dev->tx_queue_len = 3;
999 dev->type = ARPHRD_PPP;
1000 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
1001}
1002
1003/*
1004 * Transmit-side routines.
1005 */
1006
1007/*
1008 * Called to do any work queued up on the transmit side
1009 * that can now be done.
1010 */
1011static void
1012ppp_xmit_process(struct ppp *ppp)
1013{
1014 struct sk_buff *skb;
1015
1016 ppp_xmit_lock(ppp);
1017 if (ppp->dev != 0) {
1018 ppp_push(ppp);
1019 while (ppp->xmit_pending == 0
1020 && (skb = skb_dequeue(&ppp->file.xq)) != 0)
1021 ppp_send_frame(ppp, skb);
1022 /* If there's no work left to do, tell the core net
1023 code that we can accept some more. */
1024 if (ppp->xmit_pending == 0 && skb_peek(&ppp->file.xq) == 0)
1025 netif_wake_queue(ppp->dev);
1026 }
1027 ppp_xmit_unlock(ppp);
1028}
1029
1030/*
1031 * Compress and send a frame.
1032 * The caller should have locked the xmit path,
1033 * and xmit_pending should be 0.
1034 */
1035static void
1036ppp_send_frame(struct ppp *ppp, struct sk_buff *skb)
1037{
1038 int proto = PPP_PROTO(skb);
1039 struct sk_buff *new_skb;
1040 int len;
1041 unsigned char *cp;
1042
1043 if (proto < 0x8000) {
1044#ifdef CONFIG_PPP_FILTER
1045 /* check if we should pass this packet */
1046 /* the filter instructions are constructed assuming
1047 a four-byte PPP header on each packet */
1048 *skb_push(skb, 2) = 1;
1049 if (ppp->pass_filter
1050 && sk_run_filter(skb, ppp->pass_filter,
1051 ppp->pass_len) == 0) {
1052 if (ppp->debug & 1)
1053 printk(KERN_DEBUG "PPP: outbound frame not passed\n");
1054 kfree_skb(skb);
1055 return;
1056 }
1057 /* if this packet passes the active filter, record the time */
1058 if (!(ppp->active_filter
1059 && sk_run_filter(skb, ppp->active_filter,
1060 ppp->active_len) == 0))
1061 ppp->last_xmit = jiffies;
1062 skb_pull(skb, 2);
1063#else
1064 /* for data packets, record the time */
1065 ppp->last_xmit = jiffies;
1066#endif /* CONFIG_PPP_FILTER */
1067 }
1068
1069 ++ppp->stats.tx_packets;
1070 ppp->stats.tx_bytes += skb->len - 2;
1071
1072 switch (proto) {
1073 case PPP_IP:
1074 if (ppp->vj == 0 || (ppp->flags & SC_COMP_TCP) == 0)
1075 break;
1076 /* try to do VJ TCP header compression */
1077 new_skb = alloc_skb(skb->len + ppp->dev->hard_header_len - 2,
1078 GFP_ATOMIC);
1079 if (new_skb == 0) {
1080 printk(KERN_ERR "PPP: no memory (VJ comp pkt)\n");
1081 goto drop;
1082 }
1083 skb_reserve(new_skb, ppp->dev->hard_header_len - 2);
1084 cp = skb->data + 2;
1085 len = slhc_compress(ppp->vj, cp, skb->len - 2,
1086 new_skb->data + 2, &cp,
1087 !(ppp->flags & SC_NO_TCP_CCID));
1088 if (cp == skb->data + 2) {
1089 /* didn't compress */
1090 kfree_skb(new_skb);
1091 } else {
1092 if (cp[0] & SL_TYPE_COMPRESSED_TCP) {
1093 proto = PPP_VJC_COMP;
1094 cp[0] &= ~SL_TYPE_COMPRESSED_TCP;
1095 } else {
1096 proto = PPP_VJC_UNCOMP;
1097 cp[0] = skb->data[2];
1098 }
1099 kfree_skb(skb);
1100 skb = new_skb;
1101 cp = skb_put(skb, len + 2);
1102 cp[0] = 0;
1103 cp[1] = proto;
1104 }
1105 break;
1106
1107 case PPP_CCP:
1108 /* peek at outbound CCP frames */
1109 ppp_ccp_peek(ppp, skb, 0);
1110 break;
1111 }
1112
1113 /* try to do packet compression */
1114 if ((ppp->xstate & SC_COMP_RUN) && ppp->xc_state != 0
1115 && proto != PPP_LCP && proto != PPP_CCP) {
1116 new_skb = alloc_skb(ppp->dev->mtu + ppp->dev->hard_header_len,
1117 GFP_ATOMIC);
1118 if (new_skb == 0) {
1119 printk(KERN_ERR "PPP: no memory (comp pkt)\n");
1120 goto drop;
1121 }
1122 if (ppp->dev->hard_header_len > PPP_HDRLEN)
1123 skb_reserve(new_skb,
1124 ppp->dev->hard_header_len - PPP_HDRLEN);
1125
1126 /* compressor still expects A/C bytes in hdr */
1127 len = ppp->xcomp->compress(ppp->xc_state, skb->data - 2,
1128 new_skb->data, skb->len + 2,
1129 ppp->dev->mtu + PPP_HDRLEN);
1130 if (len > 0 && (ppp->flags & SC_CCP_UP)) {
1131 kfree_skb(skb);
1132 skb = new_skb;
1133 skb_put(skb, len);
1134 skb_pull(skb, 2); /* pull off A/C bytes */
1135 } else {
1136 /* didn't compress, or CCP not up yet */
1137 kfree_skb(new_skb);
1138 }
1139 }
1140
1141 /*
1142 * If we are waiting for traffic (demand dialling),
1143 * queue it up for pppd to receive.
1144 */
1145 if (ppp->flags & SC_LOOP_TRAFFIC) {
1146 if (ppp->file.rq.qlen > PPP_MAX_RQLEN)
1147 goto drop;
1148 skb_queue_tail(&ppp->file.rq, skb);
1149 wake_up_interruptible(&ppp->file.rwait);
1150 return;
1151 }
1152
1153 ppp->xmit_pending = skb;
1154 ppp_push(ppp);
1155 return;
1156
1157 drop:
1158 kfree_skb(skb);
1159 ++ppp->stats.tx_errors;
1160}
1161
1162/*
1163 * Try to send the frame in xmit_pending.
1164 * The caller should have the xmit path locked.
1165 */
1166static void
1167ppp_push(struct ppp *ppp)
1168{
1169 struct list_head *list;
1170 struct channel *pch;
1171 struct sk_buff *skb = ppp->xmit_pending;
1172
1173 if (skb == 0)
1174 return;
1175
1176 list = &ppp->channels;
1177 if (list_empty(list)) {
1178 /* nowhere to send the packet, just drop it */
1179 ppp->xmit_pending = NULL;
1180 kfree_skb(skb);
1181 return;
1182 }
1183
1184 if ((ppp->flags & SC_MULTILINK) == 0) {
1185 /* not doing multilink: send it down the first channel */
1186 list = list->next;
1187 pch = list_entry(list, struct channel, clist);
1188
1189 spin_lock_bh(&pch->downl);
1190 if (pch->chan) {
1191 if (pch->chan->ops->start_xmit(pch->chan, skb))
1192 ppp->xmit_pending = NULL;
1193 } else {
1194 /* channel got unregistered */
1195 kfree_skb(skb);
1196 ppp->xmit_pending = NULL;
1197 }
1198 spin_unlock_bh(&pch->downl);
1199 return;
1200 }
1201
1202#ifdef CONFIG_PPP_MULTILINK
1203 /* Multilink: fragment the packet over as many links
1204 as can take the packet at the moment. */
1205 if (!ppp_mp_explode(ppp, skb))
1206 return;
1207#endif /* CONFIG_PPP_MULTILINK */
1208
1209 ppp->xmit_pending = NULL;
1210 kfree_skb(skb);
1211}
1212
1213#ifdef CONFIG_PPP_MULTILINK
1214/*
1215 * Divide a packet to be transmitted into fragments and
1216 * send them out the individual links.
1217 */
1218static int ppp_mp_explode(struct ppp *ppp, struct sk_buff *skb)
1219{
516cd15f 1220 int len, fragsize;
1da177e4 1221 int i, bits, hdrlen, mtu;
516cd15f
PM		 1222 int flen;
1223 int navail, nfree;
1224 int nbigger;
1da177e4
LT		 1225 unsigned char *p, *q;
1226 struct list_head *list;
1227 struct channel *pch;
1228 struct sk_buff *frag;
1229 struct ppp_channel *chan;
1230
516cd15f
PM		 1231 nfree = 0; /* # channels which have no packet already queued */
1232 navail = 0; /* total # of usable channels (not deregistered) */
1da177e4 1233 hdrlen = (ppp->flags & SC_MP_XSHORTSEQ)? MPHDRLEN_SSN: MPHDRLEN;
516cd15f 1234 i = 0;
81616c5a 1235 list_for_each_entry(pch, &ppp->channels, clist) {
516cd15f
PM		 1236 navail += pch->avail = (pch->chan != NULL);
1237 if (pch->avail) {
b03efcfb
DM		 1238 if (skb_queue_empty(&pch->file.xq) ||
1239 !pch->had_frag) {
516cd15f
PM		 1240 pch->avail = 2;
1241 ++nfree;
1da177e4 1242 }
516cd15f
PM		 1243 if (!pch->had_frag && i < ppp->nxchan)
1244 ppp->nxchan = i;
1da177e4 1245 }
516cd15f 1246 ++i;
1da177e4 1247 }
516cd15f
PM		 1248
1249 /*
1250 * Don't start sending this packet unless at least half of
1251 * the channels are free. This gives much better TCP
1252 * performance if we have a lot of channels.
1253 */
1254 if (nfree == 0 || nfree < navail / 2)
1da177e4
LT		 1255 return 0; /* can't take now, leave it in xmit_pending */
1256
1257 /* Do protocol field compression (XXX this should be optional) */
1258 p = skb->data;
1259 len = skb->len;
1260 if (*p == 0) {
1261 ++p;
1262 --len;
1263 }
1264
516cd15f
PM		 1265 /*
1266 * Decide on fragment size.
1267 * We create a fragment for each free channel regardless of
1268 * how small they are (i.e. even 0 length) in order to minimize
1269 * the time that it will take to detect when a channel drops
1270 * a fragment.
1271 */
1da177e4 1272 fragsize = len;
516cd15f
PM		 1273 if (nfree > 1)
1274 fragsize = ROUNDUP(fragsize, nfree);
1275 /* nbigger channels get fragsize bytes, the rest get fragsize-1,
1276 except if nbigger==0, then they all get fragsize. */
1277 nbigger = len % nfree;
1da177e4
LT		 1278
1279 /* skip to the channel after the one we last used
1280 and start at that one */
81616c5a 1281 list = &ppp->channels;
1da177e4
LT		 1282 for (i = 0; i < ppp->nxchan; ++i) {
1283 list = list->next;
1284 if (list == &ppp->channels) {
1285 i = 0;
1286 break;
1287 }
1288 }
1289
1290 /* create a fragment for each channel */
1291 bits = B;
516cd15f 1292 while (nfree > 0 || len > 0) {
1da177e4
LT		 1293 list = list->next;
1294 if (list == &ppp->channels) {
1295 i = 0;
1296 continue;
1297 }
1298 pch = list_entry(list, struct channel, clist);
1299 ++i;
1300 if (!pch->avail)
1301 continue;
1302
516cd15f
PM		 1303 /*
1304 * Skip this channel if it has a fragment pending already and
1305 * we haven't given a fragment to all of the free channels.
1306 */
1307 if (pch->avail == 1) {
1308 if (nfree > 0)
1309 continue;
1310 } else {
1311 --nfree;
1312 pch->avail = 1;
1313 }
1314
1da177e4
LT		 1315 /* check the channel's mtu and whether it is still attached. */
1316 spin_lock_bh(&pch->downl);
516cd15f
PM		 1317 if (pch->chan == NULL) {
1318 /* can't use this channel, it's being deregistered */
1da177e4
LT		 1319 spin_unlock_bh(&pch->downl);
1320 pch->avail = 0;
516cd15f 1321 if (--navail == 0)
1da177e4
LT		 1322 break;
1323 continue;
1324 }
1325
1326 /*
516cd15f
PM		 1327 * Create a fragment for this channel of
1328 * min(max(mtu+2-hdrlen, 4), fragsize, len) bytes.
1329 * If mtu+2-hdrlen < 4, that is a ridiculously small
1330 * MTU, so we use mtu = 2 + hdrlen.
1da177e4
LT		 1331 */
1332 if (fragsize > len)
1333 fragsize = len;
516cd15f
PM		 1334 flen = fragsize;
1335 mtu = pch->chan->mtu + 2 - hdrlen;
1336 if (mtu < 4)
1337 mtu = 4;
1338 if (flen > mtu)
1339 flen = mtu;
1340 if (flen == len && nfree == 0)
1341 bits |= E;
1342 frag = alloc_skb(flen + hdrlen + (flen == 0), GFP_ATOMIC);
1343 if (frag == 0)
1344 goto noskb;
1345 q = skb_put(frag, flen + hdrlen);
1346
1347 /* make the MP header */
1348 q[0] = PPP_MP >> 8;
1349 q[1] = PPP_MP;
1350 if (ppp->flags & SC_MP_XSHORTSEQ) {
1351 q[2] = bits + ((ppp->nxseq >> 8) & 0xf);
1352 q[3] = ppp->nxseq;
1353 } else {
1354 q[2] = bits;
1355 q[3] = ppp->nxseq >> 16;
1356 q[4] = ppp->nxseq >> 8;
1357 q[5] = ppp->nxseq;
1da177e4 1358 }
516cd15f
PM		 1359
1360 /*
1361 * Copy the data in.
1362 * Unfortunately there is a bug in older versions of
1363 * the Linux PPP multilink reconstruction code where it
1364 * drops 0-length fragments. Therefore we make sure the
1365 * fragment has at least one byte of data. Any bytes
1366 * we add in this situation will end up as padding on the
1367 * end of the reconstructed packet.
1368 */
1369 if (flen == 0)
1370 *skb_put(frag, 1) = 0;
1371 else
1372 memcpy(q + hdrlen, p, flen);
1373
1374 /* try to send it down the channel */
1375 chan = pch->chan;
b03efcfb
DM		 1376 if (!skb_queue_empty(&pch->file.xq) ||
1377 !chan->ops->start_xmit(chan, frag))
516cd15f
PM		 1378 skb_queue_tail(&pch->file.xq, frag);
1379 pch->had_frag = 1;
1380 p += flen;
1381 len -= flen;
1382 ++ppp->nxseq;
1383 bits = 0;
1da177e4 1384 spin_unlock_bh(&pch->downl);
516cd15f
PM		 1385
1386 if (--nbigger == 0 && fragsize > 0)
1387 --fragsize;
1388 }
1da177e4
LT		 1389 ppp->nxchan = i;
1390
1391 return 1;
1392
1393 noskb:
1394 spin_unlock_bh(&pch->downl);
1395 if (ppp->debug & 1)
1396 printk(KERN_ERR "PPP: no memory (fragment)\n");
1397 ++ppp->stats.tx_errors;
1398 ++ppp->nxseq;
1399 return 1; /* abandon the frame */
1400}
1401#endif /* CONFIG_PPP_MULTILINK */
1402
1403/*
1404 * Try to send data out on a channel.
1405 */
1406static void
1407ppp_channel_push(struct channel *pch)
1408{
1409 struct sk_buff *skb;
1410 struct ppp *ppp;
1411
1412 spin_lock_bh(&pch->downl);
1413 if (pch->chan != 0) {
b03efcfb 1414 while (!skb_queue_empty(&pch->file.xq)) {
1da177e4
LT		 1415 skb = skb_dequeue(&pch->file.xq);
1416 if (!pch->chan->ops->start_xmit(pch->chan, skb)) {
1417 /* put the packet back and try again later */
1418 skb_queue_head(&pch->file.xq, skb);
1419 break;
1420 }
1421 }
1422 } else {
1423 /* channel got deregistered */
1424 skb_queue_purge(&pch->file.xq);
1425 }
1426 spin_unlock_bh(&pch->downl);
1427 /* see if there is anything from the attached unit to be sent */
b03efcfb 1428 if (skb_queue_empty(&pch->file.xq)) {
1da177e4
LT		 1429 read_lock_bh(&pch->upl);
1430 ppp = pch->ppp;
1431 if (ppp != 0)
1432 ppp_xmit_process(ppp);
1433 read_unlock_bh(&pch->upl);
1434 }
1435}
1436
1437/*
1438 * Receive-side routines.
1439 */
1440
1441/* misuse a few fields of the skb for MP reconstruction */
1442#define sequence priority
1443#define BEbits cb[0]
1444
1445static inline void
1446ppp_do_recv(struct ppp *ppp, struct sk_buff *skb, struct channel *pch)
1447{
1448 ppp_recv_lock(ppp);
1449 /* ppp->dev == 0 means interface is closing down */
1450 if (ppp->dev != 0)
1451 ppp_receive_frame(ppp, skb, pch);
1452 else
1453 kfree_skb(skb);
1454 ppp_recv_unlock(ppp);
1455}
1456
1457void
1458ppp_input(struct ppp_channel *chan, struct sk_buff *skb)
1459{
1460 struct channel *pch = chan->ppp;
1461 int proto;
1462
1463 if (pch == 0 || skb->len == 0) {
1464 kfree_skb(skb);
1465 return;
1466 }
516cd15f 1467
1da177e4
LT		 1468 proto = PPP_PROTO(skb);
1469 read_lock_bh(&pch->upl);
1470 if (pch->ppp == 0 || proto >= 0xc000 || proto == PPP_CCPFRAG) {
1471 /* put it on the channel queue */
1472 skb_queue_tail(&pch->file.rq, skb);
1473 /* drop old frames if queue too long */
1474 while (pch->file.rq.qlen > PPP_MAX_RQLEN
1475 && (skb = skb_dequeue(&pch->file.rq)) != 0)
1476 kfree_skb(skb);
1477 wake_up_interruptible(&pch->file.rwait);
1478 } else {
1479 ppp_do_recv(pch->ppp, skb, pch);
1480 }
1481 read_unlock_bh(&pch->upl);
1482}
1483
1484/* Put a 0-length skb in the receive queue as an error indication */
1485void
1486ppp_input_error(struct ppp_channel *chan, int code)
1487{
1488 struct channel *pch = chan->ppp;
1489 struct sk_buff *skb;
1490
1491 if (pch == 0)
1492 return;
1493
1494 read_lock_bh(&pch->upl);
1495 if (pch->ppp != 0) {
1496 skb = alloc_skb(0, GFP_ATOMIC);
1497 if (skb != 0) {
1498 skb->len = 0; /* probably unnecessary */
1499 skb->cb[0] = code;
1500 ppp_do_recv(pch->ppp, skb, pch);
1501 }
1502 }
1503 read_unlock_bh(&pch->upl);
1504}
1505
1506/*
1507 * We come in here to process a received frame.
1508 * The receive side of the ppp unit is locked.
1509 */
1510static void
1511ppp_receive_frame(struct ppp *ppp, struct sk_buff *skb, struct channel *pch)
1512{
1513 if (skb->len >= 2) {
1514#ifdef CONFIG_PPP_MULTILINK
1515 /* XXX do channel-level decompression here */
1516 if (PPP_PROTO(skb) == PPP_MP)
1517 ppp_receive_mp_frame(ppp, skb, pch);
1518 else
1519#endif /* CONFIG_PPP_MULTILINK */
1520 ppp_receive_nonmp_frame(ppp, skb);
1521 return;
1522 }
1523
1524 if (skb->len > 0)
1525 /* note: a 0-length skb is used as an error indication */
1526 ++ppp->stats.rx_length_errors;
1527
1528 kfree_skb(skb);
1529 ppp_receive_error(ppp);
1530}
1531
1532static void
1533ppp_receive_error(struct ppp *ppp)
1534{
1535 ++ppp->stats.rx_errors;
1536 if (ppp->vj != 0)
1537 slhc_toss(ppp->vj);
1538}
1539
1540static void
1541ppp_receive_nonmp_frame(struct ppp *ppp, struct sk_buff *skb)
1542{
1543 struct sk_buff *ns;
1544 int proto, len, npi;
1545
1546 /*
1547 * Decompress the frame, if compressed.
1548 * Note that some decompressors need to see uncompressed frames
1549 * that come in as well as compressed frames.
1550 */
1551 if (ppp->rc_state != 0 && (ppp->rstate & SC_DECOMP_RUN)
1552 && (ppp->rstate & (SC_DC_FERROR | SC_DC_ERROR)) == 0)
1553 skb = ppp_decompress_frame(ppp, skb);
1554
1555 proto = PPP_PROTO(skb);
1556 switch (proto) {
1557 case PPP_VJC_COMP:
1558 /* decompress VJ compressed packets */
1559 if (ppp->vj == 0 || (ppp->flags & SC_REJ_COMP_TCP))
1560 goto err;
1561
1562 if (skb_tailroom(skb) < 124) {
1563 /* copy to a new sk_buff with more tailroom */
1564 ns = dev_alloc_skb(skb->len + 128);
1565 if (ns == 0) {
1566 printk(KERN_ERR"PPP: no memory (VJ decomp)\n");
1567 goto err;
1568 }
1569 skb_reserve(ns, 2);
1570 skb_copy_bits(skb, 0, skb_put(ns, skb->len), skb->len);
1571 kfree_skb(skb);
1572 skb = ns;
1573 }
1574 else if (!pskb_may_pull(skb, skb->len))
1575 goto err;
1576
1577 len = slhc_uncompress(ppp->vj, skb->data + 2, skb->len - 2);
1578 if (len <= 0) {
1579 printk(KERN_DEBUG "PPP: VJ decompression error\n");
1580 goto err;
1581 }
1582 len += 2;
1583 if (len > skb->len)
1584 skb_put(skb, len - skb->len);
1585 else if (len < skb->len)
1586 skb_trim(skb, len);
1587 proto = PPP_IP;
1588 break;
1589
1590 case PPP_VJC_UNCOMP:
1591 if (ppp->vj == 0 || (ppp->flags & SC_REJ_COMP_TCP))
1592 goto err;
1593
1594 /* Until we fix the decompressor need to make sure
1595 * data portion is linear.
1596 */
1597 if (!pskb_may_pull(skb, skb->len))
1598 goto err;
1599
1600 if (slhc_remember(ppp->vj, skb->data + 2, skb->len - 2) <= 0) {
1601 printk(KERN_ERR "PPP: VJ uncompressed error\n");
1602 goto err;
1603 }
1604 proto = PPP_IP;
1605 break;
1606
1607 case PPP_CCP:
1608 ppp_ccp_peek(ppp, skb, 1);
1609 break;
1610 }
1611
1612 ++ppp->stats.rx_packets;
1613 ppp->stats.rx_bytes += skb->len - 2;
1614
1615 npi = proto_to_npindex(proto);
1616 if (npi < 0) {
1617 /* control or unknown frame - pass it to pppd */
1618 skb_queue_tail(&ppp->file.rq, skb);
1619 /* limit queue length by dropping old frames */
1620 while (ppp->file.rq.qlen > PPP_MAX_RQLEN
1621 && (skb = skb_dequeue(&ppp->file.rq)) != 0)
1622 kfree_skb(skb);
1623 /* wake up any process polling or blocking on read */
1624 wake_up_interruptible(&ppp->file.rwait);
1625
1626 } else {
1627 /* network protocol frame - give it to the kernel */
1628
1629#ifdef CONFIG_PPP_FILTER
1630 /* check if the packet passes the pass and active filters */
1631 /* the filter instructions are constructed assuming
1632 a four-byte PPP header on each packet */
1633 *skb_push(skb, 2) = 0;
1634 if (ppp->pass_filter
1635 && sk_run_filter(skb, ppp->pass_filter,
1636 ppp->pass_len) == 0) {
1637 if (ppp->debug & 1)
1638 printk(KERN_DEBUG "PPP: inbound frame not passed\n");
1639 kfree_skb(skb);
1640 return;
1641 }
1642 if (!(ppp->active_filter
1643 && sk_run_filter(skb, ppp->active_filter,
1644 ppp->active_len) == 0))
1645 ppp->last_recv = jiffies;
1646 skb_pull(skb, 2);
1647#else
1648 ppp->last_recv = jiffies;
1649#endif /* CONFIG_PPP_FILTER */
1650
1651 if ((ppp->dev->flags & IFF_UP) == 0
1652 || ppp->npmode[npi] != NPMODE_PASS) {
1653 kfree_skb(skb);
1654 } else {
1655 skb_pull(skb, 2); /* chop off protocol */
1656 skb->dev = ppp->dev;
1657 skb->protocol = htons(npindex_to_ethertype[npi]);
1658 skb->mac.raw = skb->data;
1da177e4
LT		 1659 netif_rx(skb);
1660 ppp->dev->last_rx = jiffies;
1661 }
1662 }
1663 return;
1664
1665 err:
1666 kfree_skb(skb);
1667 ppp_receive_error(ppp);
1668}
1669
1670static struct sk_buff *
1671ppp_decompress_frame(struct ppp *ppp, struct sk_buff *skb)
1672{
1673 int proto = PPP_PROTO(skb);
1674 struct sk_buff *ns;
1675 int len;
1676
1677 /* Until we fix all the decompressor's need to make sure
1678 * data portion is linear.
1679 */
1680 if (!pskb_may_pull(skb, skb->len))
1681 goto err;
1682
1683 if (proto == PPP_COMP) {
1684 ns = dev_alloc_skb(ppp->mru + PPP_HDRLEN);
1685 if (ns == 0) {
1686 printk(KERN_ERR "ppp_decompress_frame: no memory\n");
1687 goto err;
1688 }
1689 /* the decompressor still expects the A/C bytes in the hdr */
1690 len = ppp->rcomp->decompress(ppp->rc_state, skb->data - 2,
1691 skb->len + 2, ns->data, ppp->mru + PPP_HDRLEN);
1692 if (len < 0) {
1693 /* Pass the compressed frame to pppd as an
1694 error indication. */
1695 if (len == DECOMP_FATALERROR)
1696 ppp->rstate |= SC_DC_FERROR;
1697 kfree_skb(ns);
1698 goto err;
1699 }
1700
1701 kfree_skb(skb);
1702 skb = ns;
1703 skb_put(skb, len);
1704 skb_pull(skb, 2); /* pull off the A/C bytes */
1705
1706 } else {
1707 /* Uncompressed frame - pass to decompressor so it
1708 can update its dictionary if necessary. */
1709 if (ppp->rcomp->incomp)
1710 ppp->rcomp->incomp(ppp->rc_state, skb->data - 2,
1711 skb->len + 2);
1712 }
1713
1714 return skb;
1715
1716 err:
1717 ppp->rstate |= SC_DC_ERROR;
1718 ppp_receive_error(ppp);
1719 return skb;
1720}
1721
1722#ifdef CONFIG_PPP_MULTILINK
1723/*
1724 * Receive a multilink frame.
1725 * We put it on the reconstruction queue and then pull off
1726 * as many completed frames as we can.
1727 */
1728static void
1729ppp_receive_mp_frame(struct ppp *ppp, struct sk_buff *skb, struct channel *pch)
1730{
1731 u32 mask, seq;
81616c5a 1732 struct channel *ch;
1da177e4
LT		 1733 int mphdrlen = (ppp->flags & SC_MP_SHORTSEQ)? MPHDRLEN_SSN: MPHDRLEN;
1734
516cd15f 1735 if (!pskb_may_pull(skb, mphdrlen) || ppp->mrru == 0)
1da177e4
LT		 1736 goto err; /* no good, throw it away */
1737
1738 /* Decode sequence number and begin/end bits */
1739 if (ppp->flags & SC_MP_SHORTSEQ) {
1740 seq = ((skb->data[2] & 0x0f) << 8) | skb->data[3];
1741 mask = 0xfff;
1742 } else {
1743 seq = (skb->data[3] << 16) | (skb->data[4] << 8)| skb->data[5];
1744 mask = 0xffffff;
1745 }
1746 skb->BEbits = skb->data[2];
1747 skb_pull(skb, mphdrlen); /* pull off PPP and MP headers */
1748
1749 /*
1750 * Do protocol ID decompression on the first fragment of each packet.
1751 */
1752 if ((skb->BEbits & B) && (skb->data[0] & 1))
1753 *skb_push(skb, 1) = 0;
1754
1755 /*
1756 * Expand sequence number to 32 bits, making it as close
1757 * as possible to ppp->minseq.
1758 */
1759 seq |= ppp->minseq & ~mask;
1760 if ((int)(ppp->minseq - seq) > (int)(mask >> 1))
1761 seq += mask + 1;
1762 else if ((int)(seq - ppp->minseq) > (int)(mask >> 1))
1763 seq -= mask + 1; /* should never happen */
1764 skb->sequence = seq;
1765 pch->lastseq = seq;
1766
1767 /*
1768 * If this packet comes before the next one we were expecting,
1769 * drop it.
1770 */
1771 if (seq_before(seq, ppp->nextseq)) {
1772 kfree_skb(skb);
1773 ++ppp->stats.rx_dropped;
1774 ppp_receive_error(ppp);
1775 return;
1776 }
1777
1778 /*
1779 * Reevaluate minseq, the minimum over all channels of the
1780 * last sequence number received on each channel. Because of
1781 * the increasing sequence number rule, we know that any fragment
1782 * before `minseq' which hasn't arrived is never going to arrive.
1783 * The list of channels can't change because we have the receive
1784 * side of the ppp unit locked.
1785 */
81616c5a 1786 list_for_each_entry(ch, &ppp->channels, clist) {
1da177e4
LT		 1787 if (seq_before(ch->lastseq, seq))
1788 seq = ch->lastseq;
1789 }
1790 if (seq_before(ppp->minseq, seq))
1791 ppp->minseq = seq;
1792
1793 /* Put the fragment on the reconstruction queue */
1794 ppp_mp_insert(ppp, skb);
1795
1796 /* If the queue is getting long, don't wait any longer for packets
1797 before the start of the queue. */
1798 if (skb_queue_len(&ppp->mrq) >= PPP_MP_MAX_QLEN
1799 && seq_before(ppp->minseq, ppp->mrq.next->sequence))
1800 ppp->minseq = ppp->mrq.next->sequence;
1801
1802 /* Pull completed packets off the queue and receive them. */
1803 while ((skb = ppp_mp_reconstruct(ppp)) != 0)
1804 ppp_receive_nonmp_frame(ppp, skb);
1805
1806 return;
1807
1808 err:
1809 kfree_skb(skb);
1810 ppp_receive_error(ppp);
1811}
1812
1813/*
1814 * Insert a fragment on the MP reconstruction queue.
1815 * The queue is ordered by increasing sequence number.
1816 */
1817static void
1818ppp_mp_insert(struct ppp *ppp, struct sk_buff *skb)
1819{
1820 struct sk_buff *p;
1821 struct sk_buff_head *list = &ppp->mrq;
1822 u32 seq = skb->sequence;
1823
1824 /* N.B. we don't need to lock the list lock because we have the
1825 ppp unit receive-side lock. */
1826 for (p = list->next; p != (struct sk_buff *)list; p = p->next)
1827 if (seq_before(seq, p->sequence))
1828 break;
1829 __skb_insert(skb, p->prev, p, list);
1830}
1831
1832/*
1833 * Reconstruct a packet from the MP fragment queue.
1834 * We go through increasing sequence numbers until we find a
1835 * complete packet, or we get to the sequence number for a fragment
1836 * which hasn't arrived but might still do so.
1837 */
1838struct sk_buff *
1839ppp_mp_reconstruct(struct ppp *ppp)
1840{
1841 u32 seq = ppp->nextseq;
1842 u32 minseq = ppp->minseq;
1843 struct sk_buff_head *list = &ppp->mrq;
1844 struct sk_buff *p, *next;
1845 struct sk_buff *head, *tail;
1846 struct sk_buff *skb = NULL;
1847 int lost = 0, len = 0;
1848
1849 if (ppp->mrru == 0) /* do nothing until mrru is set */
1850 return NULL;
1851 head = list->next;
1852 tail = NULL;
1853 for (p = head; p != (struct sk_buff *) list; p = next) {
1854 next = p->next;
1855 if (seq_before(p->sequence, seq)) {
1856 /* this can't happen, anyway ignore the skb */
1857 printk(KERN_ERR "ppp_mp_reconstruct bad seq %u < %u\n",
1858 p->sequence, seq);
1859 head = next;
1860 continue;
1861 }
1862 if (p->sequence != seq) {
1863 /* Fragment `seq' is missing. If it is after
1864 minseq, it might arrive later, so stop here. */
1865 if (seq_after(seq, minseq))
1866 break;
1867 /* Fragment `seq' is lost, keep going. */
1868 lost = 1;
1869 seq = seq_before(minseq, p->sequence)?
1870 minseq + 1: p->sequence;
1871 next = p;
1872 continue;
1873 }
1874
1875 /*
1876 * At this point we know that all the fragments from
1877 * ppp->nextseq to seq are either present or lost.
1878 * Also, there are no complete packets in the queue
1879 * that have no missing fragments and end before this
1880 * fragment.
1881 */
1882
1883 /* B bit set indicates this fragment starts a packet */
1884 if (p->BEbits & B) {
1885 head = p;
1886 lost = 0;
1887 len = 0;
1888 }
1889
1890 len += p->len;
1891
1892 /* Got a complete packet yet? */
1893 if (lost == 0 && (p->BEbits & E) && (head->BEbits & B)) {
1894 if (len > ppp->mrru + 2) {
1895 ++ppp->stats.rx_length_errors;
1896 printk(KERN_DEBUG "PPP: reconstructed packet"
1897 " is too long (%d)\n", len);
1898 } else if (p == head) {
1899 /* fragment is complete packet - reuse skb */
1900 tail = p;
1901 skb = skb_get(p);
1902 break;
1903 } else if ((skb = dev_alloc_skb(len)) == NULL) {
1904 ++ppp->stats.rx_missed_errors;
1905 printk(KERN_DEBUG "PPP: no memory for "
1906 "reconstructed packet");
1907 } else {
1908 tail = p;
1909 break;
1910 }
1911 ppp->nextseq = seq + 1;
1912 }
1913
1914 /*
1915 * If this is the ending fragment of a packet,
1916 * and we haven't found a complete valid packet yet,
1917 * we can discard up to and including this fragment.
1918 */
1919 if (p->BEbits & E)
1920 head = next;
1921
1922 ++seq;
1923 }
1924
1925 /* If we have a complete packet, copy it all into one skb. */
1926 if (tail != NULL) {
1927 /* If we have discarded any fragments,
1928 signal a receive error. */
1929 if (head->sequence != ppp->nextseq) {
1930 if (ppp->debug & 1)
1931 printk(KERN_DEBUG " missed pkts %u..%u\n",
1932 ppp->nextseq, head->sequence-1);
1933 ++ppp->stats.rx_dropped;
1934 ppp_receive_error(ppp);
1935 }
1936
1937 if (head != tail)
1938 /* copy to a single skb */
1939 for (p = head; p != tail->next; p = p->next)
1940 skb_copy_bits(p, 0, skb_put(skb, p->len), p->len);
1941 ppp->nextseq = tail->sequence + 1;
1942 head = tail->next;
1943 }
1944
1945 /* Discard all the skbuffs that we have copied the data out of
1946 or that we can't use. */
1947 while ((p = list->next) != head) {
1948 __skb_unlink(p, list);
1949 kfree_skb(p);
1950 }
1951
1952 return skb;
1953}
1954#endif /* CONFIG_PPP_MULTILINK */
1955
1956/*
1957 * Channel interface.
1958 */
1959
1960/*
1961 * Create a new, unattached ppp channel.
1962 */
1963int
1964ppp_register_channel(struct ppp_channel *chan)
1965{
1966 struct channel *pch;
1967
1968 pch = kmalloc(sizeof(struct channel), GFP_KERNEL);
1969 if (pch == 0)
1970 return -ENOMEM;
1971 memset(pch, 0, sizeof(struct channel));
1972 pch->ppp = NULL;
1973 pch->chan = chan;
1974 chan->ppp = pch;
1975 init_ppp_file(&pch->file, CHANNEL);
1976 pch->file.hdrlen = chan->hdrlen;
1977#ifdef CONFIG_PPP_MULTILINK
1978 pch->lastseq = -1;
1979#endif /* CONFIG_PPP_MULTILINK */
1980 init_rwsem(&pch->chan_sem);
1981 spin_lock_init(&pch->downl);
1982 rwlock_init(&pch->upl);
1983 spin_lock_bh(&all_channels_lock);
1984 pch->file.index = ++last_channel_index;
1985 list_add(&pch->list, &new_channels);
1986 atomic_inc(&channel_count);
1987 spin_unlock_bh(&all_channels_lock);
1988 return 0;
1989}
1990
1991/*
1992 * Return the index of a channel.
1993 */
1994int ppp_channel_index(struct ppp_channel *chan)
1995{
1996 struct channel *pch = chan->ppp;
1997
1998 if (pch != 0)
1999 return pch->file.index;
2000 return -1;
2001}
2002
2003/*
2004 * Return the PPP unit number to which a channel is connected.
2005 */
2006int ppp_unit_number(struct ppp_channel *chan)
2007{
2008 struct channel *pch = chan->ppp;
2009 int unit = -1;
2010
2011 if (pch != 0) {
2012 read_lock_bh(&pch->upl);
2013 if (pch->ppp != 0)
2014 unit = pch->ppp->file.index;
2015 read_unlock_bh(&pch->upl);
2016 }
2017 return unit;
2018}
2019
2020/*
2021 * Disconnect a channel from the generic layer.
2022 * This must be called in process context.
2023 */
2024void
2025ppp_unregister_channel(struct ppp_channel *chan)
2026{
2027 struct channel *pch = chan->ppp;
2028
2029 if (pch == 0)
2030 return; /* should never happen */
2031 chan->ppp = NULL;
2032
2033 /*
2034 * This ensures that we have returned from any calls into the
2035 * the channel's start_xmit or ioctl routine before we proceed.
2036 */
2037 down_write(&pch->chan_sem);
2038 spin_lock_bh(&pch->downl);
2039 pch->chan = NULL;
2040 spin_unlock_bh(&pch->downl);
2041 up_write(&pch->chan_sem);
2042 ppp_disconnect_channel(pch);
2043 spin_lock_bh(&all_channels_lock);
2044 list_del(&pch->list);
2045 spin_unlock_bh(&all_channels_lock);
2046 pch->file.dead = 1;
2047 wake_up_interruptible(&pch->file.rwait);
2048 if (atomic_dec_and_test(&pch->file.refcnt))
2049 ppp_destroy_channel(pch);
2050}
2051
2052/*
2053 * Callback from a channel when it can accept more to transmit.
2054 * This should be called at BH/softirq level, not interrupt level.
2055 */
2056void
2057ppp_output_wakeup(struct ppp_channel *chan)
2058{
2059 struct channel *pch = chan->ppp;
2060
2061 if (pch == 0)
2062 return;
2063 ppp_channel_push(pch);
2064}
2065
2066/*
2067 * Compression control.
2068 */
2069
2070/* Process the PPPIOCSCOMPRESS ioctl. */
2071static int
2072ppp_set_compress(struct ppp *ppp, unsigned long arg)
2073{
2074 int err;
2075 struct compressor *cp, *ocomp;
2076 struct ppp_option_data data;
2077 void *state, *ostate;
2078 unsigned char ccp_option[CCP_MAX_OPTION_LENGTH];
2079
2080 err = -EFAULT;
2081 if (copy_from_user(&data, (void __user *) arg, sizeof(data))
2082 || (data.length <= CCP_MAX_OPTION_LENGTH
2083 && copy_from_user(ccp_option, (void __user *) data.ptr, data.length)))
2084 goto out;
2085 err = -EINVAL;
2086 if (data.length > CCP_MAX_OPTION_LENGTH
2087 || ccp_option[1] < 2 || ccp_option[1] > data.length)
2088 goto out;
2089
2090 cp = find_compressor(ccp_option[0]);
2091#ifdef CONFIG_KMOD
2092 if (cp == 0) {
2093 request_module("ppp-compress-%d", ccp_option[0]);
2094 cp = find_compressor(ccp_option[0]);
2095 }
2096#endif /* CONFIG_KMOD */
2097 if (cp == 0)
2098 goto out;
2099
2100 err = -ENOBUFS;
2101 if (data.transmit) {
2102 state = cp->comp_alloc(ccp_option, data.length);
2103 if (state != 0) {
2104 ppp_xmit_lock(ppp);
2105 ppp->xstate &= ~SC_COMP_RUN;
2106 ocomp = ppp->xcomp;
2107 ostate = ppp->xc_state;
2108 ppp->xcomp = cp;
2109 ppp->xc_state = state;
2110 ppp_xmit_unlock(ppp);
2111 if (ostate != 0) {
2112 ocomp->comp_free(ostate);
2113 module_put(ocomp->owner);
2114 }
2115 err = 0;
2116 } else
2117 module_put(cp->owner);
2118
2119 } else {
2120 state = cp->decomp_alloc(ccp_option, data.length);
2121 if (state != 0) {
2122 ppp_recv_lock(ppp);
2123 ppp->rstate &= ~SC_DECOMP_RUN;
2124 ocomp = ppp->rcomp;
2125 ostate = ppp->rc_state;
2126 ppp->rcomp = cp;
2127 ppp->rc_state = state;
2128 ppp_recv_unlock(ppp);
2129 if (ostate != 0) {
2130 ocomp->decomp_free(ostate);
2131 module_put(ocomp->owner);
2132 }
2133 err = 0;
2134 } else
2135 module_put(cp->owner);
2136 }
2137
2138 out:
2139 return err;
2140}
2141
2142/*
2143 * Look at a CCP packet and update our state accordingly.
2144 * We assume the caller has the xmit or recv path locked.
2145 */
2146static void
2147ppp_ccp_peek(struct ppp *ppp, struct sk_buff *skb, int inbound)
2148{
2149 unsigned char *dp;
2150 int len;
2151
2152 if (!pskb_may_pull(skb, CCP_HDRLEN + 2))
2153 return; /* no header */
2154 dp = skb->data + 2;
2155
2156 switch (CCP_CODE(dp)) {
2157 case CCP_CONFREQ:
2158
2159 /* A ConfReq starts negotiation of compression
2160 * in one direction of transmission,
2161 * and hence brings it down...but which way?
2162 *
2163 * Remember:
2164 * A ConfReq indicates what the sender would like to receive
2165 */
2166 if(inbound)
2167 /* He is proposing what I should send */
2168 ppp->xstate &= ~SC_COMP_RUN;
2169 else
2170 /* I am proposing to what he should send */
2171 ppp->rstate &= ~SC_DECOMP_RUN;
2172
2173 break;
2174
2175 case CCP_TERMREQ:
2176 case CCP_TERMACK:
2177 /*
2178 * CCP is going down, both directions of transmission
2179 */
2180 ppp->rstate &= ~SC_DECOMP_RUN;
2181 ppp->xstate &= ~SC_COMP_RUN;
2182 break;
2183
2184 case CCP_CONFACK:
2185 if ((ppp->flags & (SC_CCP_OPEN | SC_CCP_UP)) != SC_CCP_OPEN)
2186 break;
2187 len = CCP_LENGTH(dp);
2188 if (!pskb_may_pull(skb, len + 2))
2189 return; /* too short */
2190 dp += CCP_HDRLEN;
2191 len -= CCP_HDRLEN;
2192 if (len < CCP_OPT_MINLEN || len < CCP_OPT_LENGTH(dp))
2193 break;
2194 if (inbound) {
2195 /* we will start receiving compressed packets */
2196 if (ppp->rc_state == 0)
2197 break;
2198 if (ppp->rcomp->decomp_init(ppp->rc_state, dp, len,
2199 ppp->file.index, 0, ppp->mru, ppp->debug)) {
2200 ppp->rstate |= SC_DECOMP_RUN;
2201 ppp->rstate &= ~(SC_DC_ERROR | SC_DC_FERROR);
2202 }
2203 } else {
2204 /* we will soon start sending compressed packets */
2205 if (ppp->xc_state == 0)
2206 break;
2207 if (ppp->xcomp->comp_init(ppp->xc_state, dp, len,
2208 ppp->file.index, 0, ppp->debug))
2209 ppp->xstate |= SC_COMP_RUN;
2210 }
2211 break;
2212
2213 case CCP_RESETACK:
2214 /* reset the [de]compressor */
2215 if ((ppp->flags & SC_CCP_UP) == 0)
2216 break;
2217 if (inbound) {
2218 if (ppp->rc_state && (ppp->rstate & SC_DECOMP_RUN)) {
2219 ppp->rcomp->decomp_reset(ppp->rc_state);
2220 ppp->rstate &= ~SC_DC_ERROR;
2221 }
2222 } else {
2223 if (ppp->xc_state && (ppp->xstate & SC_COMP_RUN))
2224 ppp->xcomp->comp_reset(ppp->xc_state);
2225 }
2226 break;
2227 }
2228}
2229
2230/* Free up compression resources. */
2231static void
2232ppp_ccp_closed(struct ppp *ppp)
2233{
2234 void *xstate, *rstate;
2235 struct compressor *xcomp, *rcomp;
2236
2237 ppp_lock(ppp);
2238 ppp->flags &= ~(SC_CCP_OPEN | SC_CCP_UP);
2239 ppp->xstate = 0;
2240 xcomp = ppp->xcomp;
2241 xstate = ppp->xc_state;
2242 ppp->xc_state = NULL;
2243 ppp->rstate = 0;
2244 rcomp = ppp->rcomp;
2245 rstate = ppp->rc_state;
2246 ppp->rc_state = NULL;
2247 ppp_unlock(ppp);
2248
2249 if (xstate) {
2250 xcomp->comp_free(xstate);
2251 module_put(xcomp->owner);
2252 }
2253 if (rstate) {
2254 rcomp->decomp_free(rstate);
2255 module_put(rcomp->owner);
2256 }
2257}
2258
2259/* List of compressors. */
2260static LIST_HEAD(compressor_list);
2261static DEFINE_SPINLOCK(compressor_list_lock);
2262
2263struct compressor_entry {
2264 struct list_head list;
2265 struct compressor *comp;
2266};
2267
2268static struct compressor_entry *
2269find_comp_entry(int proto)
2270{
2271 struct compressor_entry *ce;
1da177e4 2272
81616c5a 2273 list_for_each_entry(ce, &compressor_list, list) {
1da177e4
LT		 2274 if (ce->comp->compress_proto == proto)
2275 return ce;
2276 }
2277 return NULL;
2278}
2279
2280/* Register a compressor */
2281int
2282ppp_register_compressor(struct compressor *cp)
2283{
2284 struct compressor_entry *ce;
2285 int ret;
2286 spin_lock(&compressor_list_lock);
2287 ret = -EEXIST;
2288 if (find_comp_entry(cp->compress_proto) != 0)
2289 goto out;
2290 ret = -ENOMEM;
2291 ce = kmalloc(sizeof(struct compressor_entry), GFP_ATOMIC);
2292 if (ce == 0)
2293 goto out;
2294 ret = 0;
2295 ce->comp = cp;
2296 list_add(&ce->list, &compressor_list);
2297 out:
2298 spin_unlock(&compressor_list_lock);
2299 return ret;
2300}
2301
2302/* Unregister a compressor */
2303void
2304ppp_unregister_compressor(struct compressor *cp)
2305{
2306 struct compressor_entry *ce;
2307
2308 spin_lock(&compressor_list_lock);
2309 ce = find_comp_entry(cp->compress_proto);
2310 if (ce != 0 && ce->comp == cp) {
2311 list_del(&ce->list);
2312 kfree(ce);
2313 }
2314 spin_unlock(&compressor_list_lock);
2315}
2316
2317/* Find a compressor. */
2318static struct compressor *
2319find_compressor(int type)
2320{
2321 struct compressor_entry *ce;
2322 struct compressor *cp = NULL;
2323
2324 spin_lock(&compressor_list_lock);
2325 ce = find_comp_entry(type);
2326 if (ce != 0) {
2327 cp = ce->comp;
2328 if (!try_module_get(cp->owner))
2329 cp = NULL;
2330 }
2331 spin_unlock(&compressor_list_lock);
2332 return cp;
2333}
2334
2335/*
2336 * Miscelleneous stuff.
2337 */
2338
2339static void
2340ppp_get_stats(struct ppp *ppp, struct ppp_stats *st)
2341{
2342 struct slcompress *vj = ppp->vj;
2343
2344 memset(st, 0, sizeof(*st));
2345 st->p.ppp_ipackets = ppp->stats.rx_packets;
2346 st->p.ppp_ierrors = ppp->stats.rx_errors;
2347 st->p.ppp_ibytes = ppp->stats.rx_bytes;
2348 st->p.ppp_opackets = ppp->stats.tx_packets;
2349 st->p.ppp_oerrors = ppp->stats.tx_errors;
2350 st->p.ppp_obytes = ppp->stats.tx_bytes;
2351 if (vj == 0)
2352 return;
2353 st->vj.vjs_packets = vj->sls_o_compressed + vj->sls_o_uncompressed;
2354 st->vj.vjs_compressed = vj->sls_o_compressed;
2355 st->vj.vjs_searches = vj->sls_o_searches;
2356 st->vj.vjs_misses = vj->sls_o_misses;
2357 st->vj.vjs_errorin = vj->sls_i_error;
2358 st->vj.vjs_tossed = vj->sls_i_tossed;
2359 st->vj.vjs_uncompressedin = vj->sls_i_uncompressed;
2360 st->vj.vjs_compressedin = vj->sls_i_compressed;
2361}
2362
2363/*
2364 * Stuff for handling the lists of ppp units and channels
2365 * and for initialization.
2366 */
2367
2368/*
2369 * Create a new ppp interface unit. Fails if it can't allocate memory
2370 * or if there is already a unit with the requested number.
2371 * unit == -1 means allocate a new number.
2372 */
2373static struct ppp *
2374ppp_create_interface(int unit, int *retp)
2375{
2376 struct ppp *ppp;
2377 struct net_device *dev = NULL;
2378 int ret = -ENOMEM;
2379 int i;
2380
2381 ppp = kmalloc(sizeof(struct ppp), GFP_KERNEL);
2382 if (!ppp)
2383 goto out;
2384 dev = alloc_netdev(0, "", ppp_setup);
2385 if (!dev)
2386 goto out1;
2387 memset(ppp, 0, sizeof(struct ppp));
2388
2389 ppp->mru = PPP_MRU;
2390 init_ppp_file(&ppp->file, INTERFACE);
2391 ppp->file.hdrlen = PPP_HDRLEN - 2; /* don't count proto bytes */
2392 for (i = 0; i < NUM_NP; ++i)
2393 ppp->npmode[i] = NPMODE_PASS;
2394 INIT_LIST_HEAD(&ppp->channels);
2395 spin_lock_init(&ppp->rlock);
2396 spin_lock_init(&ppp->wlock);
2397#ifdef CONFIG_PPP_MULTILINK
2398 ppp->minseq = -1;
2399 skb_queue_head_init(&ppp->mrq);
2400#endif /* CONFIG_PPP_MULTILINK */
2401 ppp->dev = dev;
2402 dev->priv = ppp;
2403
2404 dev->hard_start_xmit = ppp_start_xmit;
2405 dev->get_stats = ppp_net_stats;
2406 dev->do_ioctl = ppp_net_ioctl;
2407
2408 ret = -EEXIST;
2409 down(&all_ppp_sem);
2410 if (unit < 0)
2411 unit = cardmap_find_first_free(all_ppp_units);
2412 else if (cardmap_get(all_ppp_units, unit) != NULL)
2413 goto out2; /* unit already exists */
2414
2415 /* Initialize the new ppp unit */
2416 ppp->file.index = unit;
2417 sprintf(dev->name, "ppp%d", unit);
2418
2419 ret = register_netdev(dev);
2420 if (ret != 0) {
2421 printk(KERN_ERR "PPP: couldn't register device %s (%d)\n",
2422 dev->name, ret);
2423 goto out2;
2424 }
2425
2426 atomic_inc(&ppp_unit_count);
2427 cardmap_set(&all_ppp_units, unit, ppp);
2428 up(&all_ppp_sem);
2429 *retp = 0;
2430 return ppp;
2431
2432out2:
2433 up(&all_ppp_sem);
2434 free_netdev(dev);
2435out1:
2436 kfree(ppp);
2437out:
2438 *retp = ret;
2439 return NULL;
2440}
2441
2442/*
2443 * Initialize a ppp_file structure.
2444 */
2445static void
2446init_ppp_file(struct ppp_file *pf, int kind)
2447{
2448 pf->kind = kind;
2449 skb_queue_head_init(&pf->xq);
2450 skb_queue_head_init(&pf->rq);
2451 atomic_set(&pf->refcnt, 1);
2452 init_waitqueue_head(&pf->rwait);
2453}
2454
2455/*
2456 * Take down a ppp interface unit - called when the owning file
2457 * (the one that created the unit) is closed or detached.
2458 */
2459static void ppp_shutdown_interface(struct ppp *ppp)
2460{
2461 struct net_device *dev;
2462
2463 down(&all_ppp_sem);
2464 ppp_lock(ppp);
2465 dev = ppp->dev;
2466 ppp->dev = NULL;
2467 ppp_unlock(ppp);
2468 /* This will call dev_close() for us. */
2469 if (dev) {
2470 unregister_netdev(dev);
2471 free_netdev(dev);
2472 }
2473 cardmap_set(&all_ppp_units, ppp->file.index, NULL);
2474 ppp->file.dead = 1;
2475 ppp->owner = NULL;
2476 wake_up_interruptible(&ppp->file.rwait);
2477 up(&all_ppp_sem);
2478}
2479
2480/*
2481 * Free the memory used by a ppp unit. This is only called once
2482 * there are no channels connected to the unit and no file structs
2483 * that reference the unit.
2484 */
2485static void ppp_destroy_interface(struct ppp *ppp)
2486{
2487 atomic_dec(&ppp_unit_count);
2488
2489 if (!ppp->file.dead || ppp->n_channels) {
2490 /* "can't happen" */
2491 printk(KERN_ERR "ppp: destroying ppp struct %p but dead=%d "
2492 "n_channels=%d !\n", ppp, ppp->file.dead,
2493 ppp->n_channels);
2494 return;
2495 }
2496
2497 ppp_ccp_closed(ppp);
2498 if (ppp->vj) {
2499 slhc_free(ppp->vj);
2500 ppp->vj = NULL;
2501 }
2502 skb_queue_purge(&ppp->file.xq);
2503 skb_queue_purge(&ppp->file.rq);
2504#ifdef CONFIG_PPP_MULTILINK
2505 skb_queue_purge(&ppp->mrq);
2506#endif /* CONFIG_PPP_MULTILINK */
2507#ifdef CONFIG_PPP_FILTER
96edf83c
JJ		 2508 kfree(ppp->pass_filter);
2509 ppp->pass_filter = NULL;
2510 kfree(ppp->active_filter);
2511 ppp->active_filter = NULL;
1da177e4
LT		 2512#endif /* CONFIG_PPP_FILTER */
2513
2514 kfree(ppp);
2515}
2516
2517/*
2518 * Locate an existing ppp unit.
2519 * The caller should have locked the all_ppp_sem.
2520 */
2521static struct ppp *
2522ppp_find_unit(int unit)
2523{
2524 return cardmap_get(all_ppp_units, unit);
2525}
2526
2527/*
2528 * Locate an existing ppp channel.
2529 * The caller should have locked the all_channels_lock.
2530 * First we look in the new_channels list, then in the
2531 * all_channels list. If found in the new_channels list,
2532 * we move it to the all_channels list. This is for speed
2533 * when we have a lot of channels in use.
2534 */
2535static struct channel *
2536ppp_find_channel(int unit)
2537{
2538 struct channel *pch;
1da177e4 2539
81616c5a 2540 list_for_each_entry(pch, &new_channels, list) {
1da177e4
LT		 2541 if (pch->file.index == unit) {
2542 list_del(&pch->list);
2543 list_add(&pch->list, &all_channels);
2544 return pch;
2545 }
2546 }
81616c5a 2547 list_for_each_entry(pch, &all_channels, list) {
1da177e4
LT		 2548 if (pch->file.index == unit)
2549 return pch;
2550 }
2551 return NULL;
2552}
2553
2554/*
2555 * Connect a PPP channel to a PPP interface unit.
2556 */
2557static int
2558ppp_connect_channel(struct channel *pch, int unit)
2559{
2560 struct ppp *ppp;
2561 int ret = -ENXIO;
2562 int hdrlen;
2563
2564 down(&all_ppp_sem);
2565 ppp = ppp_find_unit(unit);
2566 if (ppp == 0)
2567 goto out;
2568 write_lock_bh(&pch->upl);
2569 ret = -EINVAL;
2570 if (pch->ppp != 0)
2571 goto outl;
2572
2573 ppp_lock(ppp);
2574 if (pch->file.hdrlen > ppp->file.hdrlen)
2575 ppp->file.hdrlen = pch->file.hdrlen;
2576 hdrlen = pch->file.hdrlen + 2; /* for protocol bytes */
2577 if (ppp->dev && hdrlen > ppp->dev->hard_header_len)
2578 ppp->dev->hard_header_len = hdrlen;
2579 list_add_tail(&pch->clist, &ppp->channels);
2580 ++ppp->n_channels;
2581 pch->ppp = ppp;
2582 atomic_inc(&ppp->file.refcnt);
2583 ppp_unlock(ppp);
2584 ret = 0;
2585
2586 outl:
2587 write_unlock_bh(&pch->upl);
2588 out:
2589 up(&all_ppp_sem);
2590 return ret;
2591}
2592
2593/*
2594 * Disconnect a channel from its ppp unit.
2595 */
2596static int
2597ppp_disconnect_channel(struct channel *pch)
2598{
2599 struct ppp *ppp;
2600 int err = -EINVAL;
2601
2602 write_lock_bh(&pch->upl);
2603 ppp = pch->ppp;
2604 pch->ppp = NULL;
2605 write_unlock_bh(&pch->upl);
2606 if (ppp != 0) {
2607 /* remove it from the ppp unit's list */
2608 ppp_lock(ppp);
2609 list_del(&pch->clist);
2610 if (--ppp->n_channels == 0)
2611 wake_up_interruptible(&ppp->file.rwait);
2612 ppp_unlock(ppp);
2613 if (atomic_dec_and_test(&ppp->file.refcnt))
2614 ppp_destroy_interface(ppp);
2615 err = 0;
2616 }
2617 return err;
2618}
2619
2620/*
2621 * Free up the resources used by a ppp channel.
2622 */
2623static void ppp_destroy_channel(struct channel *pch)
2624{
2625 atomic_dec(&channel_count);
2626
2627 if (!pch->file.dead) {
2628 /* "can't happen" */
2629 printk(KERN_ERR "ppp: destroying undead channel %p !\n",
2630 pch);
2631 return;
2632 }
2633 skb_queue_purge(&pch->file.xq);
2634 skb_queue_purge(&pch->file.rq);
2635 kfree(pch);
2636}
2637
2638static void __exit ppp_cleanup(void)
2639{
2640 /* should never happen */
2641 if (atomic_read(&ppp_unit_count) || atomic_read(&channel_count))
2642 printk(KERN_ERR "PPP: removing module but units remain!\n");
2643 cardmap_destroy(&all_ppp_units);
2644 if (unregister_chrdev(PPP_MAJOR, "ppp") != 0)
2645 printk(KERN_ERR "PPP: failed to unregister PPP device\n");
2646 devfs_remove("ppp");
56b22935
GKH		 2647 class_device_destroy(ppp_class, MKDEV(PPP_MAJOR, 0));
2648 class_destroy(ppp_class);
1da177e4
LT		 2649}
2650
2651/*
2652 * Cardmap implementation.
2653 */
2654static void *cardmap_get(struct cardmap *map, unsigned int nr)
2655{
2656 struct cardmap *p;
2657 int i;
2658
2659 for (p = map; p != NULL; ) {
2660 if ((i = nr >> p->shift) >= CARDMAP_WIDTH)
2661 return NULL;
2662 if (p->shift == 0)
2663 return p->ptr[i];
2664 nr &= ~(CARDMAP_MASK << p->shift);
2665 p = p->ptr[i];
2666 }
2667 return NULL;
2668}
2669
2670static void cardmap_set(struct cardmap **pmap, unsigned int nr, void *ptr)
2671{
2672 struct cardmap *p;
2673 int i;
2674
2675 p = *pmap;
2676 if (p == NULL || (nr >> p->shift) >= CARDMAP_WIDTH) {
2677 do {
2678 /* need a new top level */
2679 struct cardmap *np = kmalloc(sizeof(*np), GFP_KERNEL);
2680 memset(np, 0, sizeof(*np));
2681 np->ptr[0] = p;
2682 if (p != NULL) {
2683 np->shift = p->shift + CARDMAP_ORDER;
2684 p->parent = np;
2685 } else
2686 np->shift = 0;
2687 p = np;
2688 } while ((nr >> p->shift) >= CARDMAP_WIDTH);
2689 *pmap = p;
2690 }
2691 while (p->shift > 0) {
2692 i = (nr >> p->shift) & CARDMAP_MASK;
2693 if (p->ptr[i] == NULL) {
2694 struct cardmap *np = kmalloc(sizeof(*np), GFP_KERNEL);
2695 memset(np, 0, sizeof(*np));
2696 np->shift = p->shift - CARDMAP_ORDER;
2697 np->parent = p;
2698 p->ptr[i] = np;
2699 }
2700 if (ptr == NULL)
2701 clear_bit(i, &p->inuse);
2702 p = p->ptr[i];
2703 }
2704 i = nr & CARDMAP_MASK;
2705 p->ptr[i] = ptr;
2706 if (ptr != NULL)
2707 set_bit(i, &p->inuse);
2708 else
2709 clear_bit(i, &p->inuse);
2710}
2711
2712static unsigned int cardmap_find_first_free(struct cardmap *map)
2713{
2714 struct cardmap *p;
2715 unsigned int nr = 0;
2716 int i;
2717
2718 if ((p = map) == NULL)
2719 return 0;
2720 for (;;) {
2721 i = find_first_zero_bit(&p->inuse, CARDMAP_WIDTH);
2722 if (i >= CARDMAP_WIDTH) {
2723 if (p->parent == NULL)
2724 return CARDMAP_WIDTH << p->shift;
2725 p = p->parent;
2726 i = (nr >> p->shift) & CARDMAP_MASK;
2727 set_bit(i, &p->inuse);
2728 continue;
2729 }
2730 nr = (nr & (~CARDMAP_MASK << p->shift)) | (i << p->shift);
2731 if (p->shift == 0 || p->ptr[i] == NULL)
2732 return nr;
2733 p = p->ptr[i];
2734 }
2735}
2736
2737static void cardmap_destroy(struct cardmap **pmap)
2738{
2739 struct cardmap *p, *np;
2740 int i;
2741
2742 for (p = *pmap; p != NULL; p = np) {
2743 if (p->shift != 0) {
2744 for (i = 0; i < CARDMAP_WIDTH; ++i)
2745 if (p->ptr[i] != NULL)
2746 break;
2747 if (i < CARDMAP_WIDTH) {
2748 np = p->ptr[i];
2749 p->ptr[i] = NULL;
2750 continue;
2751 }
2752 }
2753 np = p->parent;
2754 kfree(p);
2755 }
2756 *pmap = NULL;
2757}
2758
2759/* Module/initialization stuff */
2760
2761module_init(ppp_init);
2762module_exit(ppp_cleanup);
2763
2764EXPORT_SYMBOL(ppp_register_channel);
2765EXPORT_SYMBOL(ppp_unregister_channel);
2766EXPORT_SYMBOL(ppp_channel_index);
2767EXPORT_SYMBOL(ppp_unit_number);
2768EXPORT_SYMBOL(ppp_input);
2769EXPORT_SYMBOL(ppp_input_error);
2770EXPORT_SYMBOL(ppp_output_wakeup);
2771EXPORT_SYMBOL(ppp_register_compressor);
2772EXPORT_SYMBOL(ppp_unregister_compressor);
2773MODULE_LICENSE("GPL");
2774MODULE_ALIAS_CHARDEV_MAJOR(PPP_MAJOR);
2775MODULE_ALIAS("/dev/ppp");
Clone of davem's net-next-2.6 tree