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jme: Do not enable NIC WoL functions on S0
[linux/fpc-iii.git] / drivers / net / ppp / ppp_generic.c
blob2b5ac1818797da19f4c39d41d56b894391d992c2
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/module.h>
26 #include <linux/kernel.h>
27 #include <linux/kmod.h>
28 #include <linux/init.h>
29 #include <linux/list.h>
30 #include <linux/idr.h>
31 #include <linux/netdevice.h>
32 #include <linux/poll.h>
33 #include <linux/ppp_defs.h>
34 #include <linux/filter.h>
35 #include <linux/ppp-ioctl.h>
36 #include <linux/ppp_channel.h>
37 #include <linux/ppp-comp.h>
38 #include <linux/skbuff.h>
39 #include <linux/rtnetlink.h>
40 #include <linux/if_arp.h>
41 #include <linux/ip.h>
42 #include <linux/tcp.h>
43 #include <linux/spinlock.h>
44 #include <linux/rwsem.h>
45 #include <linux/stddef.h>
46 #include <linux/device.h>
47 #include <linux/mutex.h>
48 #include <linux/slab.h>
49 #include <asm/unaligned.h>
50 #include <net/slhc_vj.h>
51 #include <linux/atomic.h>
52
53 #include <linux/nsproxy.h>
54 #include <net/net_namespace.h>
55 #include <net/netns/generic.h>
56
57 #define PPP_VERSION "2.4.2"
58
59 /*
60 * Network protocols we support.
61 */
62 #define NP_IP 0 /* Internet Protocol V4 */
63 #define NP_IPV6 1 /* Internet Protocol V6 */
64 #define NP_IPX 2 /* IPX protocol */
65 #define NP_AT 3 /* Appletalk protocol */
66 #define NP_MPLS_UC 4 /* MPLS unicast */
67 #define NP_MPLS_MC 5 /* MPLS multicast */
68 #define NUM_NP 6 /* Number of NPs. */
69
70 #define MPHDRLEN 6 /* multilink protocol header length */
71 #define MPHDRLEN_SSN 4 /* ditto with short sequence numbers */
72
73 /*
74 * An instance of /dev/ppp can be associated with either a ppp
75 * interface unit or a ppp channel. In both cases, file->private_data
76 * points to one of these.
77 */
78 struct ppp_file {
79 enum {
80 INTERFACE=1, CHANNEL
81 } kind;
82 struct sk_buff_head xq; /* pppd transmit queue */
83 struct sk_buff_head rq; /* receive queue for pppd */
84 wait_queue_head_t rwait; /* for poll on reading /dev/ppp */
85 atomic_t refcnt; /* # refs (incl /dev/ppp attached) */
86 int hdrlen; /* space to leave for headers */
87 int index; /* interface unit / channel number */
88 int dead; /* unit/channel has been shut down */
89 };
90
91 #define PF_TO_X(pf, X) container_of(pf, X, file)
92
93 #define PF_TO_PPP(pf) PF_TO_X(pf, struct ppp)
94 #define PF_TO_CHANNEL(pf) PF_TO_X(pf, struct channel)
95
96 /*
97 * Data structure to hold primary network stats for which
98 * we want to use 64 bit storage. Other network stats
99 * are stored in dev->stats of the ppp strucute.
100 */
101 struct ppp_link_stats {
102 u64 rx_packets;
103 u64 tx_packets;
104 u64 rx_bytes;
105 u64 tx_bytes;
106 };
107
108 /*
109 * Data structure describing one ppp unit.
110 * A ppp unit corresponds to a ppp network interface device
111 * and represents a multilink bundle.
112 * It can have 0 or more ppp channels connected to it.
113 */
114 struct ppp {
115 struct ppp_file file; /* stuff for read/write/poll 0 */
116 struct file *owner; /* file that owns this unit 48 */
117 struct list_head channels; /* list of attached channels 4c */
118 int n_channels; /* how many channels are attached 54 */
119 spinlock_t rlock; /* lock for receive side 58 */
120 spinlock_t wlock; /* lock for transmit side 5c */
121 int mru; /* max receive unit 60 */
122 unsigned int flags; /* control bits 64 */
123 unsigned int xstate; /* transmit state bits 68 */
124 unsigned int rstate; /* receive state bits 6c */
125 int debug; /* debug flags 70 */
126 struct slcompress *vj; /* state for VJ header compression */
127 enum NPmode npmode[NUM_NP]; /* what to do with each net proto 78 */
128 struct sk_buff *xmit_pending; /* a packet ready to go out 88 */
129 struct compressor *xcomp; /* transmit packet compressor 8c */
130 void *xc_state; /* its internal state 90 */
131 struct compressor *rcomp; /* receive decompressor 94 */
132 void *rc_state; /* its internal state 98 */
133 unsigned long last_xmit; /* jiffies when last pkt sent 9c */
134 unsigned long last_recv; /* jiffies when last pkt rcvd a0 */
135 struct net_device *dev; /* network interface device a4 */
136 int closing; /* is device closing down? a8 */
137 #ifdef CONFIG_PPP_MULTILINK
138 int nxchan; /* next channel to send something on */
139 u32 nxseq; /* next sequence number to send */
140 int mrru; /* MP: max reconst. receive unit */
141 u32 nextseq; /* MP: seq no of next packet */
142 u32 minseq; /* MP: min of most recent seqnos */
143 struct sk_buff_head mrq; /* MP: receive reconstruction queue */
144 #endif /* CONFIG_PPP_MULTILINK */
145 #ifdef CONFIG_PPP_FILTER
146 struct sk_filter *pass_filter; /* filter for packets to pass */
147 struct sk_filter *active_filter;/* filter for pkts to reset idle */
148 #endif /* CONFIG_PPP_FILTER */
149 struct net *ppp_net; /* the net we belong to */
150 struct ppp_link_stats stats64; /* 64 bit network stats */
151 };
152
153 /*
154 * Bits in flags: SC_NO_TCP_CCID, SC_CCP_OPEN, SC_CCP_UP, SC_LOOP_TRAFFIC,
155 * SC_MULTILINK, SC_MP_SHORTSEQ, SC_MP_XSHORTSEQ, SC_COMP_TCP, SC_REJ_COMP_TCP,
156 * SC_MUST_COMP
157 * Bits in rstate: SC_DECOMP_RUN, SC_DC_ERROR, SC_DC_FERROR.
158 * Bits in xstate: SC_COMP_RUN
159 */
160 #define SC_FLAG_BITS (SC_NO_TCP_CCID|SC_CCP_OPEN|SC_CCP_UP|SC_LOOP_TRAFFIC \
161 |SC_MULTILINK|SC_MP_SHORTSEQ|SC_MP_XSHORTSEQ \
162 |SC_COMP_TCP|SC_REJ_COMP_TCP|SC_MUST_COMP)
163
164 /*
165 * Private data structure for each channel.
166 * This includes the data structure used for multilink.
167 */
168 struct channel {
169 struct ppp_file file; /* stuff for read/write/poll */
170 struct list_head list; /* link in all/new_channels list */
171 struct ppp_channel *chan; /* public channel data structure */
172 struct rw_semaphore chan_sem; /* protects `chan' during chan ioctl */
173 spinlock_t downl; /* protects `chan', file.xq dequeue */
174 struct ppp *ppp; /* ppp unit we're connected to */
175 struct net *chan_net; /* the net channel belongs to */
176 struct list_head clist; /* link in list of channels per unit */
177 rwlock_t upl; /* protects `ppp' */
178 #ifdef CONFIG_PPP_MULTILINK
179 u8 avail; /* flag used in multilink stuff */
180 u8 had_frag; /* >= 1 fragments have been sent */
181 u32 lastseq; /* MP: last sequence # received */
182 int speed; /* speed of the corresponding ppp channel*/
183 #endif /* CONFIG_PPP_MULTILINK */
184 };
185
186 /*
187 * SMP locking issues:
188 * Both the ppp.rlock and ppp.wlock locks protect the ppp.channels
189 * list and the ppp.n_channels field, you need to take both locks
190 * before you modify them.
191 * The lock ordering is: channel.upl -> ppp.wlock -> ppp.rlock ->
192 * channel.downl.
193 */
194
195 static DEFINE_MUTEX(ppp_mutex);
196 static atomic_t ppp_unit_count = ATOMIC_INIT(0);
197 static atomic_t channel_count = ATOMIC_INIT(0);
198
199 /* per-net private data for this module */
200 static int ppp_net_id __read_mostly;
201 struct ppp_net {
202 /* units to ppp mapping */
203 struct idr units_idr;
204
205 /*
206 * all_ppp_mutex protects the units_idr mapping.
207 * It also ensures that finding a ppp unit in the units_idr
208 * map and updating its file.refcnt field is atomic.
209 */
210 struct mutex all_ppp_mutex;
211
212 /* channels */
213 struct list_head all_channels;
214 struct list_head new_channels;
215 int last_channel_index;
216
217 /*
218 * all_channels_lock protects all_channels and
219 * last_channel_index, and the atomicity of find
220 * a channel and updating its file.refcnt field.
221 */
222 spinlock_t all_channels_lock;
223 };
224
225 /* Get the PPP protocol number from a skb */
226 #define PPP_PROTO(skb) get_unaligned_be16((skb)->data)
227
228 /* We limit the length of ppp->file.rq to this (arbitrary) value */
229 #define PPP_MAX_RQLEN 32
230
231 /*
232 * Maximum number of multilink fragments queued up.
233 * This has to be large enough to cope with the maximum latency of
234 * the slowest channel relative to the others. Strictly it should
235 * depend on the number of channels and their characteristics.
236 */
237 #define PPP_MP_MAX_QLEN 128
238
239 /* Multilink header bits. */
240 #define B 0x80 /* this fragment begins a packet */
241 #define E 0x40 /* this fragment ends a packet */
242
243 /* Compare multilink sequence numbers (assumed to be 32 bits wide) */
244 #define seq_before(a, b) ((s32)((a) - (b)) < 0)
245 #define seq_after(a, b) ((s32)((a) - (b)) > 0)
246
247 /* Prototypes. */
248 static int ppp_unattached_ioctl(struct net *net, struct ppp_file *pf,
249 struct file *file, unsigned int cmd, unsigned long arg);
250 static void ppp_xmit_process(struct ppp *ppp);
251 static void ppp_send_frame(struct ppp *ppp, struct sk_buff *skb);
252 static void ppp_push(struct ppp *ppp);
253 static void ppp_channel_push(struct channel *pch);
254 static void ppp_receive_frame(struct ppp *ppp, struct sk_buff *skb,
255 struct channel *pch);
256 static void ppp_receive_error(struct ppp *ppp);
257 static void ppp_receive_nonmp_frame(struct ppp *ppp, struct sk_buff *skb);
258 static struct sk_buff *ppp_decompress_frame(struct ppp *ppp,
259 struct sk_buff *skb);
260 #ifdef CONFIG_PPP_MULTILINK
261 static void ppp_receive_mp_frame(struct ppp *ppp, struct sk_buff *skb,
262 struct channel *pch);
263 static void ppp_mp_insert(struct ppp *ppp, struct sk_buff *skb);
264 static struct sk_buff *ppp_mp_reconstruct(struct ppp *ppp);
265 static int ppp_mp_explode(struct ppp *ppp, struct sk_buff *skb);
266 #endif /* CONFIG_PPP_MULTILINK */
267 static int ppp_set_compress(struct ppp *ppp, unsigned long arg);
268 static void ppp_ccp_peek(struct ppp *ppp, struct sk_buff *skb, int inbound);
269 static void ppp_ccp_closed(struct ppp *ppp);
270 static struct compressor *find_compressor(int type);
271 static void ppp_get_stats(struct ppp *ppp, struct ppp_stats *st);
272 static struct ppp *ppp_create_interface(struct net *net, int unit, int *retp);
273 static void init_ppp_file(struct ppp_file *pf, int kind);
274 static void ppp_shutdown_interface(struct ppp *ppp);
275 static void ppp_destroy_interface(struct ppp *ppp);
276 static struct ppp *ppp_find_unit(struct ppp_net *pn, int unit);
277 static struct channel *ppp_find_channel(struct ppp_net *pn, int unit);
278 static int ppp_connect_channel(struct channel *pch, int unit);
279 static int ppp_disconnect_channel(struct channel *pch);
280 static void ppp_destroy_channel(struct channel *pch);
281 static int unit_get(struct idr *p, void *ptr);
282 static int unit_set(struct idr *p, void *ptr, int n);
283 static void unit_put(struct idr *p, int n);
284 static void *unit_find(struct idr *p, int n);
285
286 static struct class *ppp_class;
287
288 /* per net-namespace data */
289 static inline struct ppp_net *ppp_pernet(struct net *net)
290 {
291 BUG_ON(!net);
292
293 return net_generic(net, ppp_net_id);
294 }
295
296 /* Translates a PPP protocol number to a NP index (NP == network protocol) */
297 static inline int proto_to_npindex(int proto)
298 {
299 switch (proto) {
300 case PPP_IP:
301 return NP_IP;
302 case PPP_IPV6:
303 return NP_IPV6;
304 case PPP_IPX:
305 return NP_IPX;
306 case PPP_AT:
307 return NP_AT;
308 case PPP_MPLS_UC:
309 return NP_MPLS_UC;
310 case PPP_MPLS_MC:
311 return NP_MPLS_MC;
312 }
313 return -EINVAL;
314 }
315
316 /* Translates an NP index into a PPP protocol number */
317 static const int npindex_to_proto[NUM_NP] = {
318 PPP_IP,
319 PPP_IPV6,
320 PPP_IPX,
321 PPP_AT,
322 PPP_MPLS_UC,
323 PPP_MPLS_MC,
324 };
325
326 /* Translates an ethertype into an NP index */
327 static inline int ethertype_to_npindex(int ethertype)
328 {
329 switch (ethertype) {
330 case ETH_P_IP:
331 return NP_IP;
332 case ETH_P_IPV6:
333 return NP_IPV6;
334 case ETH_P_IPX:
335 return NP_IPX;
336 case ETH_P_PPPTALK:
337 case ETH_P_ATALK:
338 return NP_AT;
339 case ETH_P_MPLS_UC:
340 return NP_MPLS_UC;
341 case ETH_P_MPLS_MC:
342 return NP_MPLS_MC;
343 }
344 return -1;
345 }
346
347 /* Translates an NP index into an ethertype */
348 static const int npindex_to_ethertype[NUM_NP] = {
349 ETH_P_IP,
350 ETH_P_IPV6,
351 ETH_P_IPX,
352 ETH_P_PPPTALK,
353 ETH_P_MPLS_UC,
354 ETH_P_MPLS_MC,
355 };
356
357 /*
358 * Locking shorthand.
359 */
360 #define ppp_xmit_lock(ppp) spin_lock_bh(&(ppp)->wlock)
361 #define ppp_xmit_unlock(ppp) spin_unlock_bh(&(ppp)->wlock)
362 #define ppp_recv_lock(ppp) spin_lock_bh(&(ppp)->rlock)
363 #define ppp_recv_unlock(ppp) spin_unlock_bh(&(ppp)->rlock)
364 #define ppp_lock(ppp) do { ppp_xmit_lock(ppp); \
365 ppp_recv_lock(ppp); } while (0)
366 #define ppp_unlock(ppp) do { ppp_recv_unlock(ppp); \
367 ppp_xmit_unlock(ppp); } while (0)
368
369 /*
370 * /dev/ppp device routines.
371 * The /dev/ppp device is used by pppd to control the ppp unit.
372 * It supports the read, write, ioctl and poll functions.
373 * Open instances of /dev/ppp can be in one of three states:
374 * unattached, attached to a ppp unit, or attached to a ppp channel.
375 */
376 static int ppp_open(struct inode *inode, struct file *file)
377 {
378 /*
379 * This could (should?) be enforced by the permissions on /dev/ppp.
380 */
381 if (!capable(CAP_NET_ADMIN))
382 return -EPERM;
383 return 0;
384 }
385
386 static int ppp_release(struct inode *unused, struct file *file)
387 {
388 struct ppp_file *pf = file->private_data;
389 struct ppp *ppp;
390
391 if (pf) {
392 file->private_data = NULL;
393 if (pf->kind == INTERFACE) {
394 ppp = PF_TO_PPP(pf);
395 if (file == ppp->owner)
396 ppp_shutdown_interface(ppp);
397 }
398 if (atomic_dec_and_test(&pf->refcnt)) {
399 switch (pf->kind) {
400 case INTERFACE:
401 ppp_destroy_interface(PF_TO_PPP(pf));
402 break;
403 case CHANNEL:
404 ppp_destroy_channel(PF_TO_CHANNEL(pf));
405 break;
406 }
407 }
408 }
409 return 0;
410 }
411
412 static ssize_t ppp_read(struct file *file, char __user *buf,
413 size_t count, loff_t *ppos)
414 {
415 struct ppp_file *pf = file->private_data;
416 DECLARE_WAITQUEUE(wait, current);
417 ssize_t ret;
418 struct sk_buff *skb = NULL;
419 struct iovec iov;
420
421 ret = count;
422
423 if (!pf)
424 return -ENXIO;
425 add_wait_queue(&pf->rwait, &wait);
426 for (;;) {
427 set_current_state(TASK_INTERRUPTIBLE);
428 skb = skb_dequeue(&pf->rq);
429 if (skb)
430 break;
431 ret = 0;
432 if (pf->dead)
433 break;
434 if (pf->kind == INTERFACE) {
435 /*
436 * Return 0 (EOF) on an interface that has no
437 * channels connected, unless it is looping
438 * network traffic (demand mode).
439 */
440 struct ppp *ppp = PF_TO_PPP(pf);
441 if (ppp->n_channels == 0 &&
442 (ppp->flags & SC_LOOP_TRAFFIC) == 0)
443 break;
444 }
445 ret = -EAGAIN;
446 if (file->f_flags & O_NONBLOCK)
447 break;
448 ret = -ERESTARTSYS;
449 if (signal_pending(current))
450 break;
451 schedule();
452 }
453 set_current_state(TASK_RUNNING);
454 remove_wait_queue(&pf->rwait, &wait);
455
456 if (!skb)
457 goto out;
458
459 ret = -EOVERFLOW;
460 if (skb->len > count)
461 goto outf;
462 ret = -EFAULT;
463 iov.iov_base = buf;
464 iov.iov_len = count;
465 if (skb_copy_datagram_iovec(skb, 0, &iov, skb->len))
466 goto outf;
467 ret = skb->len;
468
469 outf:
470 kfree_skb(skb);
471 out:
472 return ret;
473 }
474
475 static ssize_t ppp_write(struct file *file, const char __user *buf,
476 size_t count, loff_t *ppos)
477 {
478 struct ppp_file *pf = file->private_data;
479 struct sk_buff *skb;
480 ssize_t ret;
481
482 if (!pf)
483 return -ENXIO;
484 ret = -ENOMEM;
485 skb = alloc_skb(count + pf->hdrlen, GFP_KERNEL);
486 if (!skb)
487 goto out;
488 skb_reserve(skb, pf->hdrlen);
489 ret = -EFAULT;
490 if (copy_from_user(skb_put(skb, count), buf, count)) {
491 kfree_skb(skb);
492 goto out;
493 }
494
495 skb_queue_tail(&pf->xq, skb);
496
497 switch (pf->kind) {
498 case INTERFACE:
499 ppp_xmit_process(PF_TO_PPP(pf));
500 break;
501 case CHANNEL:
502 ppp_channel_push(PF_TO_CHANNEL(pf));
503 break;
504 }
505
506 ret = count;
507
508 out:
509 return ret;
510 }
511
512 /* No kernel lock - fine */
513 static unsigned int ppp_poll(struct file *file, poll_table *wait)
514 {
515 struct ppp_file *pf = file->private_data;
516 unsigned int mask;
517
518 if (!pf)
519 return 0;
520 poll_wait(file, &pf->rwait, wait);
521 mask = POLLOUT | POLLWRNORM;
522 if (skb_peek(&pf->rq))
523 mask |= POLLIN | POLLRDNORM;
524 if (pf->dead)
525 mask |= POLLHUP;
526 else if (pf->kind == INTERFACE) {
527 /* see comment in ppp_read */
528 struct ppp *ppp = PF_TO_PPP(pf);
529 if (ppp->n_channels == 0 &&
530 (ppp->flags & SC_LOOP_TRAFFIC) == 0)
531 mask |= POLLIN | POLLRDNORM;
532 }
533
534 return mask;
535 }
536
537 #ifdef CONFIG_PPP_FILTER
538 static int get_filter(void __user *arg, struct sock_filter **p)
539 {
540 struct sock_fprog uprog;
541 struct sock_filter *code = NULL;
542 int len;
543
544 if (copy_from_user(&uprog, arg, sizeof(uprog)))
545 return -EFAULT;
546
547 if (!uprog.len) {
548 *p = NULL;
549 return 0;
550 }
551
552 len = uprog.len * sizeof(struct sock_filter);
553 code = memdup_user(uprog.filter, len);
554 if (IS_ERR(code))
555 return PTR_ERR(code);
556
557 *p = code;
558 return uprog.len;
559 }
560 #endif /* CONFIG_PPP_FILTER */
561
562 static long ppp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
563 {
564 struct ppp_file *pf;
565 struct ppp *ppp;
566 int err = -EFAULT, val, val2, i;
567 struct ppp_idle idle;
568 struct npioctl npi;
569 int unit, cflags;
570 struct slcompress *vj;
571 void __user *argp = (void __user *)arg;
572 int __user *p = argp;
573
574 mutex_lock(&ppp_mutex);
575
576 pf = file->private_data;
577 if (!pf) {
578 err = ppp_unattached_ioctl(current->nsproxy->net_ns,
579 pf, file, cmd, arg);
580 goto out;
581 }
582
583 if (cmd == PPPIOCDETACH) {
584 /*
585 * We have to be careful here... if the file descriptor
586 * has been dup'd, we could have another process in the
587 * middle of a poll using the same file *, so we had
588 * better not free the interface data structures -
589 * instead we fail the ioctl. Even in this case, we
590 * shut down the interface if we are the owner of it.
591 * Actually, we should get rid of PPPIOCDETACH, userland
592 * (i.e. pppd) could achieve the same effect by closing
593 * this fd and reopening /dev/ppp.
594 */
595 err = -EINVAL;
596 if (pf->kind == INTERFACE) {
597 ppp = PF_TO_PPP(pf);
598 if (file == ppp->owner)
599 ppp_shutdown_interface(ppp);
600 }
601 if (atomic_long_read(&file->f_count) < 2) {
602 ppp_release(NULL, file);
603 err = 0;
604 } else
605 pr_warn("PPPIOCDETACH file->f_count=%ld\n",
606 atomic_long_read(&file->f_count));
607 goto out;
608 }
609
610 if (pf->kind == CHANNEL) {
611 struct channel *pch;
612 struct ppp_channel *chan;
613
614 pch = PF_TO_CHANNEL(pf);
615
616 switch (cmd) {
617 case PPPIOCCONNECT:
618 if (get_user(unit, p))
619 break;
620 err = ppp_connect_channel(pch, unit);
621 break;
622
623 case PPPIOCDISCONN:
624 err = ppp_disconnect_channel(pch);
625 break;
626
627 default:
628 down_read(&pch->chan_sem);
629 chan = pch->chan;
630 err = -ENOTTY;
631 if (chan && chan->ops->ioctl)
632 err = chan->ops->ioctl(chan, cmd, arg);
633 up_read(&pch->chan_sem);
634 }
635 goto out;
636 }
637
638 if (pf->kind != INTERFACE) {
639 /* can't happen */
640 pr_err("PPP: not interface or channel??\n");
641 err = -EINVAL;
642 goto out;
643 }
644
645 ppp = PF_TO_PPP(pf);
646 switch (cmd) {
647 case PPPIOCSMRU:
648 if (get_user(val, p))
649 break;
650 ppp->mru = val;
651 err = 0;
652 break;
653
654 case PPPIOCSFLAGS:
655 if (get_user(val, p))
656 break;
657 ppp_lock(ppp);
658 cflags = ppp->flags & ~val;
659 ppp->flags = val & SC_FLAG_BITS;
660 ppp_unlock(ppp);
661 if (cflags & SC_CCP_OPEN)
662 ppp_ccp_closed(ppp);
663 err = 0;
664 break;
665
666 case PPPIOCGFLAGS:
667 val = ppp->flags | ppp->xstate | ppp->rstate;
668 if (put_user(val, p))
669 break;
670 err = 0;
671 break;
672
673 case PPPIOCSCOMPRESS:
674 err = ppp_set_compress(ppp, arg);
675 break;
676
677 case PPPIOCGUNIT:
678 if (put_user(ppp->file.index, p))
679 break;
680 err = 0;
681 break;
682
683 case PPPIOCSDEBUG:
684 if (get_user(val, p))
685 break;
686 ppp->debug = val;
687 err = 0;
688 break;
689
690 case PPPIOCGDEBUG:
691 if (put_user(ppp->debug, p))
692 break;
693 err = 0;
694 break;
695
696 case PPPIOCGIDLE:
697 idle.xmit_idle = (jiffies - ppp->last_xmit) / HZ;
698 idle.recv_idle = (jiffies - ppp->last_recv) / HZ;
699 if (copy_to_user(argp, &idle, sizeof(idle)))
700 break;
701 err = 0;
702 break;
703
704 case PPPIOCSMAXCID:
705 if (get_user(val, p))
706 break;
707 val2 = 15;
708 if ((val >> 16) != 0) {
709 val2 = val >> 16;
710 val &= 0xffff;
711 }
712 vj = slhc_init(val2+1, val+1);
713 if (IS_ERR(vj)) {
714 err = PTR_ERR(vj);
715 break;
716 }
717 ppp_lock(ppp);
718 if (ppp->vj)
719 slhc_free(ppp->vj);
720 ppp->vj = vj;
721 ppp_unlock(ppp);
722 err = 0;
723 break;
724
725 case PPPIOCGNPMODE:
726 case PPPIOCSNPMODE:
727 if (copy_from_user(&npi, argp, sizeof(npi)))
728 break;
729 err = proto_to_npindex(npi.protocol);
730 if (err < 0)
731 break;
732 i = err;
733 if (cmd == PPPIOCGNPMODE) {
734 err = -EFAULT;
735 npi.mode = ppp->npmode[i];
736 if (copy_to_user(argp, &npi, sizeof(npi)))
737 break;
738 } else {
739 ppp->npmode[i] = npi.mode;
740 /* we may be able to transmit more packets now (??) */
741 netif_wake_queue(ppp->dev);
742 }
743 err = 0;
744 break;
745
746 #ifdef CONFIG_PPP_FILTER
747 case PPPIOCSPASS:
748 {
749 struct sock_filter *code;
750
751 err = get_filter(argp, &code);
752 if (err >= 0) {
753 struct sock_fprog_kern fprog = {
754 .len = err,
755 .filter = code,
756 };
757
758 ppp_lock(ppp);
759 if (ppp->pass_filter) {
760 sk_unattached_filter_destroy(ppp->pass_filter);
761 ppp->pass_filter = NULL;
762 }
763 if (fprog.filter != NULL)
764 err = sk_unattached_filter_create(&ppp->pass_filter,
765 &fprog);
766 else
767 err = 0;
768 kfree(code);
769 ppp_unlock(ppp);
770 }
771 break;
772 }
773 case PPPIOCSACTIVE:
774 {
775 struct sock_filter *code;
776
777 err = get_filter(argp, &code);
778 if (err >= 0) {
779 struct sock_fprog_kern fprog = {
780 .len = err,
781 .filter = code,
782 };
783
784 ppp_lock(ppp);
785 if (ppp->active_filter) {
786 sk_unattached_filter_destroy(ppp->active_filter);
787 ppp->active_filter = NULL;
788 }
789 if (fprog.filter != NULL)
790 err = sk_unattached_filter_create(&ppp->active_filter,
791 &fprog);
792 else
793 err = 0;
794 kfree(code);
795 ppp_unlock(ppp);
796 }
797 break;
798 }
799 #endif /* CONFIG_PPP_FILTER */
800
801 #ifdef CONFIG_PPP_MULTILINK
802 case PPPIOCSMRRU:
803 if (get_user(val, p))
804 break;
805 ppp_recv_lock(ppp);
806 ppp->mrru = val;
807 ppp_recv_unlock(ppp);
808 err = 0;
809 break;
810 #endif /* CONFIG_PPP_MULTILINK */
811
812 default:
813 err = -ENOTTY;
814 }
815
816 out:
817 mutex_unlock(&ppp_mutex);
818
819 return err;
820 }
821
822 static int ppp_unattached_ioctl(struct net *net, struct ppp_file *pf,
823 struct file *file, unsigned int cmd, unsigned long arg)
824 {
825 int unit, err = -EFAULT;
826 struct ppp *ppp;
827 struct channel *chan;
828 struct ppp_net *pn;
829 int __user *p = (int __user *)arg;
830
831 switch (cmd) {
832 case PPPIOCNEWUNIT:
833 /* Create a new ppp unit */
834 if (get_user(unit, p))
835 break;
836 ppp = ppp_create_interface(net, unit, &err);
837 if (!ppp)
838 break;
839 file->private_data = &ppp->file;
840 ppp->owner = file;
841 err = -EFAULT;
842 if (put_user(ppp->file.index, p))
843 break;
844 err = 0;
845 break;
846
847 case PPPIOCATTACH:
848 /* Attach to an existing ppp unit */
849 if (get_user(unit, p))
850 break;
851 err = -ENXIO;
852 pn = ppp_pernet(net);
853 mutex_lock(&pn->all_ppp_mutex);
854 ppp = ppp_find_unit(pn, unit);
855 if (ppp) {
856 atomic_inc(&ppp->file.refcnt);
857 file->private_data = &ppp->file;
858 err = 0;
859 }
860 mutex_unlock(&pn->all_ppp_mutex);
861 break;
862
863 case PPPIOCATTCHAN:
864 if (get_user(unit, p))
865 break;
866 err = -ENXIO;
867 pn = ppp_pernet(net);
868 spin_lock_bh(&pn->all_channels_lock);
869 chan = ppp_find_channel(pn, unit);
870 if (chan) {
871 atomic_inc(&chan->file.refcnt);
872 file->private_data = &chan->file;
873 err = 0;
874 }
875 spin_unlock_bh(&pn->all_channels_lock);
876 break;
877
878 default:
879 err = -ENOTTY;
880 }
881
882 return err;
883 }
884
885 static const struct file_operations ppp_device_fops = {
886 .owner = THIS_MODULE,
887 .read = ppp_read,
888 .write = ppp_write,
889 .poll = ppp_poll,
890 .unlocked_ioctl = ppp_ioctl,
891 .open = ppp_open,
892 .release = ppp_release,
893 .llseek = noop_llseek,
894 };
895
896 static __net_init int ppp_init_net(struct net *net)
897 {
898 struct ppp_net *pn = net_generic(net, ppp_net_id);
899
900 idr_init(&pn->units_idr);
901 mutex_init(&pn->all_ppp_mutex);
902
903 INIT_LIST_HEAD(&pn->all_channels);
904 INIT_LIST_HEAD(&pn->new_channels);
905
906 spin_lock_init(&pn->all_channels_lock);
907
908 return 0;
909 }
910
911 static __net_exit void ppp_exit_net(struct net *net)
912 {
913 struct ppp_net *pn = net_generic(net, ppp_net_id);
914
915 idr_destroy(&pn->units_idr);
916 }
917
918 static struct pernet_operations ppp_net_ops = {
919 .init = ppp_init_net,
920 .exit = ppp_exit_net,
921 .id = &ppp_net_id,
922 .size = sizeof(struct ppp_net),
923 };
924
925 #define PPP_MAJOR 108
926
927 /* Called at boot time if ppp is compiled into the kernel,
928 or at module load time (from init_module) if compiled as a module. */
929 static int __init ppp_init(void)
930 {
931 int err;
932
933 pr_info("PPP generic driver version " PPP_VERSION "\n");
934
935 err = register_pernet_device(&ppp_net_ops);
936 if (err) {
937 pr_err("failed to register PPP pernet device (%d)\n", err);
938 goto out;
939 }
940
941 err = register_chrdev(PPP_MAJOR, "ppp", &ppp_device_fops);
942 if (err) {
943 pr_err("failed to register PPP device (%d)\n", err);
944 goto out_net;
945 }
946
947 ppp_class = class_create(THIS_MODULE, "ppp");
948 if (IS_ERR(ppp_class)) {
949 err = PTR_ERR(ppp_class);
950 goto out_chrdev;
951 }
952
953 /* not a big deal if we fail here :-) */
954 device_create(ppp_class, NULL, MKDEV(PPP_MAJOR, 0), NULL, "ppp");
955
956 return 0;
957
958 out_chrdev:
959 unregister_chrdev(PPP_MAJOR, "ppp");
960 out_net:
961 unregister_pernet_device(&ppp_net_ops);
962 out:
963 return err;
964 }
965
966 /*
967 * Network interface unit routines.
968 */
969 static netdev_tx_t
970 ppp_start_xmit(struct sk_buff *skb, struct net_device *dev)
971 {
972 struct ppp *ppp = netdev_priv(dev);
973 int npi, proto;
974 unsigned char *pp;
975
976 npi = ethertype_to_npindex(ntohs(skb->protocol));
977 if (npi < 0)
978 goto outf;
979
980 /* Drop, accept or reject the packet */
981 switch (ppp->npmode[npi]) {
982 case NPMODE_PASS:
983 break;
984 case NPMODE_QUEUE:
985 /* it would be nice to have a way to tell the network
986 system to queue this one up for later. */
987 goto outf;
988 case NPMODE_DROP:
989 case NPMODE_ERROR:
990 goto outf;
991 }
992
993 /* Put the 2-byte PPP protocol number on the front,
994 making sure there is room for the address and control fields. */
995 if (skb_cow_head(skb, PPP_HDRLEN))
996 goto outf;
997
998 pp = skb_push(skb, 2);
999 proto = npindex_to_proto[npi];
1000 put_unaligned_be16(proto, pp);
1001
1002 skb_queue_tail(&ppp->file.xq, skb);
1003 ppp_xmit_process(ppp);
1004 return NETDEV_TX_OK;
1005
1006 outf:
1007 kfree_skb(skb);
1008 ++dev->stats.tx_dropped;
1009 return NETDEV_TX_OK;
1010 }
1011
1012 static int
1013 ppp_net_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
1014 {
1015 struct ppp *ppp = netdev_priv(dev);
1016 int err = -EFAULT;
1017 void __user *addr = (void __user *) ifr->ifr_ifru.ifru_data;
1018 struct ppp_stats stats;
1019 struct ppp_comp_stats cstats;
1020 char *vers;
1021
1022 switch (cmd) {
1023 case SIOCGPPPSTATS:
1024 ppp_get_stats(ppp, &stats);
1025 if (copy_to_user(addr, &stats, sizeof(stats)))
1026 break;
1027 err = 0;
1028 break;
1029
1030 case SIOCGPPPCSTATS:
1031 memset(&cstats, 0, sizeof(cstats));
1032 if (ppp->xc_state)
1033 ppp->xcomp->comp_stat(ppp->xc_state, &cstats.c);
1034 if (ppp->rc_state)
1035 ppp->rcomp->decomp_stat(ppp->rc_state, &cstats.d);
1036 if (copy_to_user(addr, &cstats, sizeof(cstats)))
1037 break;
1038 err = 0;
1039 break;
1040
1041 case SIOCGPPPVER:
1042 vers = PPP_VERSION;
1043 if (copy_to_user(addr, vers, strlen(vers) + 1))
1044 break;
1045 err = 0;
1046 break;
1047
1048 default:
1049 err = -EINVAL;
1050 }
1051
1052 return err;
1053 }
1054
1055 static struct rtnl_link_stats64*
1056 ppp_get_stats64(struct net_device *dev, struct rtnl_link_stats64 *stats64)
1057 {
1058 struct ppp *ppp = netdev_priv(dev);
1059
1060 ppp_recv_lock(ppp);
1061 stats64->rx_packets = ppp->stats64.rx_packets;
1062 stats64->rx_bytes = ppp->stats64.rx_bytes;
1063 ppp_recv_unlock(ppp);
1064
1065 ppp_xmit_lock(ppp);
1066 stats64->tx_packets = ppp->stats64.tx_packets;
1067 stats64->tx_bytes = ppp->stats64.tx_bytes;
1068 ppp_xmit_unlock(ppp);
1069
1070 stats64->rx_errors = dev->stats.rx_errors;
1071 stats64->tx_errors = dev->stats.tx_errors;
1072 stats64->rx_dropped = dev->stats.rx_dropped;
1073 stats64->tx_dropped = dev->stats.tx_dropped;
1074 stats64->rx_length_errors = dev->stats.rx_length_errors;
1075
1076 return stats64;
1077 }
1078
1079 static struct lock_class_key ppp_tx_busylock;
1080 static int ppp_dev_init(struct net_device *dev)
1081 {
1082 dev->qdisc_tx_busylock = &ppp_tx_busylock;
1083 return 0;
1084 }
1085
1086 static const struct net_device_ops ppp_netdev_ops = {
1087 .ndo_init = ppp_dev_init,
1088 .ndo_start_xmit = ppp_start_xmit,
1089 .ndo_do_ioctl = ppp_net_ioctl,
1090 .ndo_get_stats64 = ppp_get_stats64,
1091 };
1092
1093 static void ppp_setup(struct net_device *dev)
1094 {
1095 dev->netdev_ops = &ppp_netdev_ops;
1096 dev->hard_header_len = PPP_HDRLEN;
1097 dev->mtu = PPP_MRU;
1098 dev->addr_len = 0;
1099 dev->tx_queue_len = 3;
1100 dev->type = ARPHRD_PPP;
1101 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
1102 dev->features |= NETIF_F_NETNS_LOCAL;
1103 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
1104 }
1105
1106 /*
1107 * Transmit-side routines.
1108 */
1109
1110 /*
1111 * Called to do any work queued up on the transmit side
1112 * that can now be done.
1113 */
1114 static void
1115 ppp_xmit_process(struct ppp *ppp)
1116 {
1117 struct sk_buff *skb;
1118
1119 ppp_xmit_lock(ppp);
1120 if (!ppp->closing) {
1121 ppp_push(ppp);
1122 while (!ppp->xmit_pending &&
1123 (skb = skb_dequeue(&ppp->file.xq)))
1124 ppp_send_frame(ppp, skb);
1125 /* If there's no work left to do, tell the core net
1126 code that we can accept some more. */
1127 if (!ppp->xmit_pending && !skb_peek(&ppp->file.xq))
1128 netif_wake_queue(ppp->dev);
1129 else
1130 netif_stop_queue(ppp->dev);
1131 }
1132 ppp_xmit_unlock(ppp);
1133 }
1134
1135 static inline struct sk_buff *
1136 pad_compress_skb(struct ppp *ppp, struct sk_buff *skb)
1137 {
1138 struct sk_buff *new_skb;
1139 int len;
1140 int new_skb_size = ppp->dev->mtu +
1141 ppp->xcomp->comp_extra + ppp->dev->hard_header_len;
1142 int compressor_skb_size = ppp->dev->mtu +
1143 ppp->xcomp->comp_extra + PPP_HDRLEN;
1144 new_skb = alloc_skb(new_skb_size, GFP_ATOMIC);
1145 if (!new_skb) {
1146 if (net_ratelimit())
1147 netdev_err(ppp->dev, "PPP: no memory (comp pkt)\n");
1148 return NULL;
1149 }
1150 if (ppp->dev->hard_header_len > PPP_HDRLEN)
1151 skb_reserve(new_skb,
1152 ppp->dev->hard_header_len - PPP_HDRLEN);
1153
1154 /* compressor still expects A/C bytes in hdr */
1155 len = ppp->xcomp->compress(ppp->xc_state, skb->data - 2,
1156 new_skb->data, skb->len + 2,
1157 compressor_skb_size);
1158 if (len > 0 && (ppp->flags & SC_CCP_UP)) {
1159 consume_skb(skb);
1160 skb = new_skb;
1161 skb_put(skb, len);
1162 skb_pull(skb, 2); /* pull off A/C bytes */
1163 } else if (len == 0) {
1164 /* didn't compress, or CCP not up yet */
1165 consume_skb(new_skb);
1166 new_skb = skb;
1167 } else {
1168 /*
1169 * (len < 0)
1170 * MPPE requires that we do not send unencrypted
1171 * frames. The compressor will return -1 if we
1172 * should drop the frame. We cannot simply test
1173 * the compress_proto because MPPE and MPPC share
1174 * the same number.
1175 */
1176 if (net_ratelimit())
1177 netdev_err(ppp->dev, "ppp: compressor dropped pkt\n");
1178 kfree_skb(skb);
1179 consume_skb(new_skb);
1180 new_skb = NULL;
1181 }
1182 return new_skb;
1183 }
1184
1185 /*
1186 * Compress and send a frame.
1187 * The caller should have locked the xmit path,
1188 * and xmit_pending should be 0.
1189 */
1190 static void
1191 ppp_send_frame(struct ppp *ppp, struct sk_buff *skb)
1192 {
1193 int proto = PPP_PROTO(skb);
1194 struct sk_buff *new_skb;
1195 int len;
1196 unsigned char *cp;
1197
1198 if (proto < 0x8000) {
1199 #ifdef CONFIG_PPP_FILTER
1200 /* check if we should pass this packet */
1201 /* the filter instructions are constructed assuming
1202 a four-byte PPP header on each packet */
1203 *skb_push(skb, 2) = 1;
1204 if (ppp->pass_filter &&
1205 SK_RUN_FILTER(ppp->pass_filter, skb) == 0) {
1206 if (ppp->debug & 1)
1207 netdev_printk(KERN_DEBUG, ppp->dev,
1208 "PPP: outbound frame "
1209 "not passed\n");
1210 kfree_skb(skb);
1211 return;
1212 }
1213 /* if this packet passes the active filter, record the time */
1214 if (!(ppp->active_filter &&
1215 SK_RUN_FILTER(ppp->active_filter, skb) == 0))
1216 ppp->last_xmit = jiffies;
1217 skb_pull(skb, 2);
1218 #else
1219 /* for data packets, record the time */
1220 ppp->last_xmit = jiffies;
1221 #endif /* CONFIG_PPP_FILTER */
1222 }
1223
1224 ++ppp->stats64.tx_packets;
1225 ppp->stats64.tx_bytes += skb->len - 2;
1226
1227 switch (proto) {
1228 case PPP_IP:
1229 if (!ppp->vj || (ppp->flags & SC_COMP_TCP) == 0)
1230 break;
1231 /* try to do VJ TCP header compression */
1232 new_skb = alloc_skb(skb->len + ppp->dev->hard_header_len - 2,
1233 GFP_ATOMIC);
1234 if (!new_skb) {
1235 netdev_err(ppp->dev, "PPP: no memory (VJ comp pkt)\n");
1236 goto drop;
1237 }
1238 skb_reserve(new_skb, ppp->dev->hard_header_len - 2);
1239 cp = skb->data + 2;
1240 len = slhc_compress(ppp->vj, cp, skb->len - 2,
1241 new_skb->data + 2, &cp,
1242 !(ppp->flags & SC_NO_TCP_CCID));
1243 if (cp == skb->data + 2) {
1244 /* didn't compress */
1245 consume_skb(new_skb);
1246 } else {
1247 if (cp[0] & SL_TYPE_COMPRESSED_TCP) {
1248 proto = PPP_VJC_COMP;
1249 cp[0] &= ~SL_TYPE_COMPRESSED_TCP;
1250 } else {
1251 proto = PPP_VJC_UNCOMP;
1252 cp[0] = skb->data[2];
1253 }
1254 consume_skb(skb);
1255 skb = new_skb;
1256 cp = skb_put(skb, len + 2);
1257 cp[0] = 0;
1258 cp[1] = proto;
1259 }
1260 break;
1261
1262 case PPP_CCP:
1263 /* peek at outbound CCP frames */
1264 ppp_ccp_peek(ppp, skb, 0);
1265 break;
1266 }
1267
1268 /* try to do packet compression */
1269 if ((ppp->xstate & SC_COMP_RUN) && ppp->xc_state &&
1270 proto != PPP_LCP && proto != PPP_CCP) {
1271 if (!(ppp->flags & SC_CCP_UP) && (ppp->flags & SC_MUST_COMP)) {
1272 if (net_ratelimit())
1273 netdev_err(ppp->dev,
1274 "ppp: compression required but "
1275 "down - pkt dropped.\n");
1276 goto drop;
1277 }
1278 skb = pad_compress_skb(ppp, skb);
1279 if (!skb)
1280 goto drop;
1281 }
1282
1283 /*
1284 * If we are waiting for traffic (demand dialling),
1285 * queue it up for pppd to receive.
1286 */
1287 if (ppp->flags & SC_LOOP_TRAFFIC) {
1288 if (ppp->file.rq.qlen > PPP_MAX_RQLEN)
1289 goto drop;
1290 skb_queue_tail(&ppp->file.rq, skb);
1291 wake_up_interruptible(&ppp->file.rwait);
1292 return;
1293 }
1294
1295 ppp->xmit_pending = skb;
1296 ppp_push(ppp);
1297 return;
1298
1299 drop:
1300 kfree_skb(skb);
1301 ++ppp->dev->stats.tx_errors;
1302 }
1303
1304 /*
1305 * Try to send the frame in xmit_pending.
1306 * The caller should have the xmit path locked.
1307 */
1308 static void
1309 ppp_push(struct ppp *ppp)
1310 {
1311 struct list_head *list;
1312 struct channel *pch;
1313 struct sk_buff *skb = ppp->xmit_pending;
1314
1315 if (!skb)
1316 return;
1317
1318 list = &ppp->channels;
1319 if (list_empty(list)) {
1320 /* nowhere to send the packet, just drop it */
1321 ppp->xmit_pending = NULL;
1322 kfree_skb(skb);
1323 return;
1324 }
1325
1326 if ((ppp->flags & SC_MULTILINK) == 0) {
1327 /* not doing multilink: send it down the first channel */
1328 list = list->next;
1329 pch = list_entry(list, struct channel, clist);
1330
1331 spin_lock_bh(&pch->downl);
1332 if (pch->chan) {
1333 if (pch->chan->ops->start_xmit(pch->chan, skb))
1334 ppp->xmit_pending = NULL;
1335 } else {
1336 /* channel got unregistered */
1337 kfree_skb(skb);
1338 ppp->xmit_pending = NULL;
1339 }
1340 spin_unlock_bh(&pch->downl);
1341 return;
1342 }
1343
1344 #ifdef CONFIG_PPP_MULTILINK
1345 /* Multilink: fragment the packet over as many links
1346 as can take the packet at the moment. */
1347 if (!ppp_mp_explode(ppp, skb))
1348 return;
1349 #endif /* CONFIG_PPP_MULTILINK */
1350
1351 ppp->xmit_pending = NULL;
1352 kfree_skb(skb);
1353 }
1354
1355 #ifdef CONFIG_PPP_MULTILINK
1356 static bool mp_protocol_compress __read_mostly = true;
1357 module_param(mp_protocol_compress, bool, S_IRUGO | S_IWUSR);
1358 MODULE_PARM_DESC(mp_protocol_compress,
1359 "compress protocol id in multilink fragments");
1360
1361 /*
1362 * Divide a packet to be transmitted into fragments and
1363 * send them out the individual links.
1364 */
1365 static int ppp_mp_explode(struct ppp *ppp, struct sk_buff *skb)
1366 {
1367 int len, totlen;
1368 int i, bits, hdrlen, mtu;
1369 int flen;
1370 int navail, nfree, nzero;
1371 int nbigger;
1372 int totspeed;
1373 int totfree;
1374 unsigned char *p, *q;
1375 struct list_head *list;
1376 struct channel *pch;
1377 struct sk_buff *frag;
1378 struct ppp_channel *chan;
1379
1380 totspeed = 0; /*total bitrate of the bundle*/
1381 nfree = 0; /* # channels which have no packet already queued */
1382 navail = 0; /* total # of usable channels (not deregistered) */
1383 nzero = 0; /* number of channels with zero speed associated*/
1384 totfree = 0; /*total # of channels available and
1385 *having no queued packets before
1386 *starting the fragmentation*/
1387
1388 hdrlen = (ppp->flags & SC_MP_XSHORTSEQ)? MPHDRLEN_SSN: MPHDRLEN;
1389 i = 0;
1390 list_for_each_entry(pch, &ppp->channels, clist) {
1391 if (pch->chan) {
1392 pch->avail = 1;
1393 navail++;
1394 pch->speed = pch->chan->speed;
1395 } else {
1396 pch->avail = 0;
1397 }
1398 if (pch->avail) {
1399 if (skb_queue_empty(&pch->file.xq) ||
1400 !pch->had_frag) {
1401 if (pch->speed == 0)
1402 nzero++;
1403 else
1404 totspeed += pch->speed;
1405
1406 pch->avail = 2;
1407 ++nfree;
1408 ++totfree;
1409 }
1410 if (!pch->had_frag && i < ppp->nxchan)
1411 ppp->nxchan = i;
1412 }
1413 ++i;
1414 }
1415 /*
1416 * Don't start sending this packet unless at least half of
1417 * the channels are free. This gives much better TCP
1418 * performance if we have a lot of channels.
1419 */
1420 if (nfree == 0 || nfree < navail / 2)
1421 return 0; /* can't take now, leave it in xmit_pending */
1422
1423 /* Do protocol field compression */
1424 p = skb->data;
1425 len = skb->len;
1426 if (*p == 0 && mp_protocol_compress) {
1427 ++p;
1428 --len;
1429 }
1430
1431 totlen = len;
1432 nbigger = len % nfree;
1433
1434 /* skip to the channel after the one we last used
1435 and start at that one */
1436 list = &ppp->channels;
1437 for (i = 0; i < ppp->nxchan; ++i) {
1438 list = list->next;
1439 if (list == &ppp->channels) {
1440 i = 0;
1441 break;
1442 }
1443 }
1444
1445 /* create a fragment for each channel */
1446 bits = B;
1447 while (len > 0) {
1448 list = list->next;
1449 if (list == &ppp->channels) {
1450 i = 0;
1451 continue;
1452 }
1453 pch = list_entry(list, struct channel, clist);
1454 ++i;
1455 if (!pch->avail)
1456 continue;
1457
1458 /*
1459 * Skip this channel if it has a fragment pending already and
1460 * we haven't given a fragment to all of the free channels.
1461 */
1462 if (pch->avail == 1) {
1463 if (nfree > 0)
1464 continue;
1465 } else {
1466 pch->avail = 1;
1467 }
1468
1469 /* check the channel's mtu and whether it is still attached. */
1470 spin_lock_bh(&pch->downl);
1471 if (pch->chan == NULL) {
1472 /* can't use this channel, it's being deregistered */
1473 if (pch->speed == 0)
1474 nzero--;
1475 else
1476 totspeed -= pch->speed;
1477
1478 spin_unlock_bh(&pch->downl);
1479 pch->avail = 0;
1480 totlen = len;
1481 totfree--;
1482 nfree--;
1483 if (--navail == 0)
1484 break;
1485 continue;
1486 }
1487
1488 /*
1489 *if the channel speed is not set divide
1490 *the packet evenly among the free channels;
1491 *otherwise divide it according to the speed
1492 *of the channel we are going to transmit on
1493 */
1494 flen = len;
1495 if (nfree > 0) {
1496 if (pch->speed == 0) {
1497 flen = len/nfree;
1498 if (nbigger > 0) {
1499 flen++;
1500 nbigger--;
1501 }
1502 } else {
1503 flen = (((totfree - nzero)*(totlen + hdrlen*totfree)) /
1504 ((totspeed*totfree)/pch->speed)) - hdrlen;
1505 if (nbigger > 0) {
1506 flen += ((totfree - nzero)*pch->speed)/totspeed;
1507 nbigger -= ((totfree - nzero)*pch->speed)/
1508 totspeed;
1509 }
1510 }
1511 nfree--;
1512 }
1513
1514 /*
1515 *check if we are on the last channel or
1516 *we exceded the length of the data to
1517 *fragment
1518 */
1519 if ((nfree <= 0) || (flen > len))
1520 flen = len;
1521 /*
1522 *it is not worth to tx on slow channels:
1523 *in that case from the resulting flen according to the
1524 *above formula will be equal or less than zero.
1525 *Skip the channel in this case
1526 */
1527 if (flen <= 0) {
1528 pch->avail = 2;
1529 spin_unlock_bh(&pch->downl);
1530 continue;
1531 }
1532
1533 /*
1534 * hdrlen includes the 2-byte PPP protocol field, but the
1535 * MTU counts only the payload excluding the protocol field.
1536 * (RFC1661 Section 2)
1537 */
1538 mtu = pch->chan->mtu - (hdrlen - 2);
1539 if (mtu < 4)
1540 mtu = 4;
1541 if (flen > mtu)
1542 flen = mtu;
1543 if (flen == len)
1544 bits |= E;
1545 frag = alloc_skb(flen + hdrlen + (flen == 0), GFP_ATOMIC);
1546 if (!frag)
1547 goto noskb;
1548 q = skb_put(frag, flen + hdrlen);
1549
1550 /* make the MP header */
1551 put_unaligned_be16(PPP_MP, q);
1552 if (ppp->flags & SC_MP_XSHORTSEQ) {
1553 q[2] = bits + ((ppp->nxseq >> 8) & 0xf);
1554 q[3] = ppp->nxseq;
1555 } else {
1556 q[2] = bits;
1557 q[3] = ppp->nxseq >> 16;
1558 q[4] = ppp->nxseq >> 8;
1559 q[5] = ppp->nxseq;
1560 }
1561
1562 memcpy(q + hdrlen, p, flen);
1563
1564 /* try to send it down the channel */
1565 chan = pch->chan;
1566 if (!skb_queue_empty(&pch->file.xq) ||
1567 !chan->ops->start_xmit(chan, frag))
1568 skb_queue_tail(&pch->file.xq, frag);
1569 pch->had_frag = 1;
1570 p += flen;
1571 len -= flen;
1572 ++ppp->nxseq;
1573 bits = 0;
1574 spin_unlock_bh(&pch->downl);
1575 }
1576 ppp->nxchan = i;
1577
1578 return 1;
1579
1580 noskb:
1581 spin_unlock_bh(&pch->downl);
1582 if (ppp->debug & 1)
1583 netdev_err(ppp->dev, "PPP: no memory (fragment)\n");
1584 ++ppp->dev->stats.tx_errors;
1585 ++ppp->nxseq;
1586 return 1; /* abandon the frame */
1587 }
1588 #endif /* CONFIG_PPP_MULTILINK */
1589
1590 /*
1591 * Try to send data out on a channel.
1592 */
1593 static void
1594 ppp_channel_push(struct channel *pch)
1595 {
1596 struct sk_buff *skb;
1597 struct ppp *ppp;
1598
1599 spin_lock_bh(&pch->downl);
1600 if (pch->chan) {
1601 while (!skb_queue_empty(&pch->file.xq)) {
1602 skb = skb_dequeue(&pch->file.xq);
1603 if (!pch->chan->ops->start_xmit(pch->chan, skb)) {
1604 /* put the packet back and try again later */
1605 skb_queue_head(&pch->file.xq, skb);
1606 break;
1607 }
1608 }
1609 } else {
1610 /* channel got deregistered */
1611 skb_queue_purge(&pch->file.xq);
1612 }
1613 spin_unlock_bh(&pch->downl);
1614 /* see if there is anything from the attached unit to be sent */
1615 if (skb_queue_empty(&pch->file.xq)) {
1616 read_lock_bh(&pch->upl);
1617 ppp = pch->ppp;
1618 if (ppp)
1619 ppp_xmit_process(ppp);
1620 read_unlock_bh(&pch->upl);
1621 }
1622 }
1623
1624 /*
1625 * Receive-side routines.
1626 */
1627
1628 struct ppp_mp_skb_parm {
1629 u32 sequence;
1630 u8 BEbits;
1631 };
1632 #define PPP_MP_CB(skb) ((struct ppp_mp_skb_parm *)((skb)->cb))
1633
1634 static inline void
1635 ppp_do_recv(struct ppp *ppp, struct sk_buff *skb, struct channel *pch)
1636 {
1637 ppp_recv_lock(ppp);
1638 if (!ppp->closing)
1639 ppp_receive_frame(ppp, skb, pch);
1640 else
1641 kfree_skb(skb);
1642 ppp_recv_unlock(ppp);
1643 }
1644
1645 void
1646 ppp_input(struct ppp_channel *chan, struct sk_buff *skb)
1647 {
1648 struct channel *pch = chan->ppp;
1649 int proto;
1650
1651 if (!pch) {
1652 kfree_skb(skb);
1653 return;
1654 }
1655
1656 read_lock_bh(&pch->upl);
1657 if (!pskb_may_pull(skb, 2)) {
1658 kfree_skb(skb);
1659 if (pch->ppp) {
1660 ++pch->ppp->dev->stats.rx_length_errors;
1661 ppp_receive_error(pch->ppp);
1662 }
1663 goto done;
1664 }
1665
1666 proto = PPP_PROTO(skb);
1667 if (!pch->ppp || proto >= 0xc000 || proto == PPP_CCPFRAG) {
1668 /* put it on the channel queue */
1669 skb_queue_tail(&pch->file.rq, skb);
1670 /* drop old frames if queue too long */
1671 while (pch->file.rq.qlen > PPP_MAX_RQLEN &&
1672 (skb = skb_dequeue(&pch->file.rq)))
1673 kfree_skb(skb);
1674 wake_up_interruptible(&pch->file.rwait);
1675 } else {
1676 ppp_do_recv(pch->ppp, skb, pch);
1677 }
1678
1679 done:
1680 read_unlock_bh(&pch->upl);
1681 }
1682
1683 /* Put a 0-length skb in the receive queue as an error indication */
1684 void
1685 ppp_input_error(struct ppp_channel *chan, int code)
1686 {
1687 struct channel *pch = chan->ppp;
1688 struct sk_buff *skb;
1689
1690 if (!pch)
1691 return;
1692
1693 read_lock_bh(&pch->upl);
1694 if (pch->ppp) {
1695 skb = alloc_skb(0, GFP_ATOMIC);
1696 if (skb) {
1697 skb->len = 0; /* probably unnecessary */
1698 skb->cb[0] = code;
1699 ppp_do_recv(pch->ppp, skb, pch);
1700 }
1701 }
1702 read_unlock_bh(&pch->upl);
1703 }
1704
1705 /*
1706 * We come in here to process a received frame.
1707 * The receive side of the ppp unit is locked.
1708 */
1709 static void
1710 ppp_receive_frame(struct ppp *ppp, struct sk_buff *skb, struct channel *pch)
1711 {
1712 /* note: a 0-length skb is used as an error indication */
1713 if (skb->len > 0) {
1714 skb_checksum_complete_unset(skb);
1715 #ifdef CONFIG_PPP_MULTILINK
1716 /* XXX do channel-level decompression here */
1717 if (PPP_PROTO(skb) == PPP_MP)
1718 ppp_receive_mp_frame(ppp, skb, pch);
1719 else
1720 #endif /* CONFIG_PPP_MULTILINK */
1721 ppp_receive_nonmp_frame(ppp, skb);
1722 } else {
1723 kfree_skb(skb);
1724 ppp_receive_error(ppp);
1725 }
1726 }
1727
1728 static void
1729 ppp_receive_error(struct ppp *ppp)
1730 {
1731 ++ppp->dev->stats.rx_errors;
1732 if (ppp->vj)
1733 slhc_toss(ppp->vj);
1734 }
1735
1736 static void
1737 ppp_receive_nonmp_frame(struct ppp *ppp, struct sk_buff *skb)
1738 {
1739 struct sk_buff *ns;
1740 int proto, len, npi;
1741
1742 /*
1743 * Decompress the frame, if compressed.
1744 * Note that some decompressors need to see uncompressed frames
1745 * that come in as well as compressed frames.
1746 */
1747 if (ppp->rc_state && (ppp->rstate & SC_DECOMP_RUN) &&
1748 (ppp->rstate & (SC_DC_FERROR | SC_DC_ERROR)) == 0)
1749 skb = ppp_decompress_frame(ppp, skb);
1750
1751 if (ppp->flags & SC_MUST_COMP && ppp->rstate & SC_DC_FERROR)
1752 goto err;
1753
1754 proto = PPP_PROTO(skb);
1755 switch (proto) {
1756 case PPP_VJC_COMP:
1757 /* decompress VJ compressed packets */
1758 if (!ppp->vj || (ppp->flags & SC_REJ_COMP_TCP))
1759 goto err;
1760
1761 if (skb_tailroom(skb) < 124 || skb_cloned(skb)) {
1762 /* copy to a new sk_buff with more tailroom */
1763 ns = dev_alloc_skb(skb->len + 128);
1764 if (!ns) {
1765 netdev_err(ppp->dev, "PPP: no memory "
1766 "(VJ decomp)\n");
1767 goto err;
1768 }
1769 skb_reserve(ns, 2);
1770 skb_copy_bits(skb, 0, skb_put(ns, skb->len), skb->len);
1771 consume_skb(skb);
1772 skb = ns;
1773 }
1774 else
1775 skb->ip_summed = CHECKSUM_NONE;
1776
1777 len = slhc_uncompress(ppp->vj, skb->data + 2, skb->len - 2);
1778 if (len <= 0) {
1779 netdev_printk(KERN_DEBUG, ppp->dev,
1780 "PPP: VJ decompression error\n");
1781 goto err;
1782 }
1783 len += 2;
1784 if (len > skb->len)
1785 skb_put(skb, len - skb->len);
1786 else if (len < skb->len)
1787 skb_trim(skb, len);
1788 proto = PPP_IP;
1789 break;
1790
1791 case PPP_VJC_UNCOMP:
1792 if (!ppp->vj || (ppp->flags & SC_REJ_COMP_TCP))
1793 goto err;
1794
1795 /* Until we fix the decompressor need to make sure
1796 * data portion is linear.
1797 */
1798 if (!pskb_may_pull(skb, skb->len))
1799 goto err;
1800
1801 if (slhc_remember(ppp->vj, skb->data + 2, skb->len - 2) <= 0) {
1802 netdev_err(ppp->dev, "PPP: VJ uncompressed error\n");
1803 goto err;
1804 }
1805 proto = PPP_IP;
1806 break;
1807
1808 case PPP_CCP:
1809 ppp_ccp_peek(ppp, skb, 1);
1810 break;
1811 }
1812
1813 ++ppp->stats64.rx_packets;
1814 ppp->stats64.rx_bytes += skb->len - 2;
1815
1816 npi = proto_to_npindex(proto);
1817 if (npi < 0) {
1818 /* control or unknown frame - pass it to pppd */
1819 skb_queue_tail(&ppp->file.rq, skb);
1820 /* limit queue length by dropping old frames */
1821 while (ppp->file.rq.qlen > PPP_MAX_RQLEN &&
1822 (skb = skb_dequeue(&ppp->file.rq)))
1823 kfree_skb(skb);
1824 /* wake up any process polling or blocking on read */
1825 wake_up_interruptible(&ppp->file.rwait);
1826
1827 } else {
1828 /* network protocol frame - give it to the kernel */
1829
1830 #ifdef CONFIG_PPP_FILTER
1831 /* check if the packet passes the pass and active filters */
1832 /* the filter instructions are constructed assuming
1833 a four-byte PPP header on each packet */
1834 if (ppp->pass_filter || ppp->active_filter) {
1835 if (skb_unclone(skb, GFP_ATOMIC))
1836 goto err;
1837
1838 *skb_push(skb, 2) = 0;
1839 if (ppp->pass_filter &&
1840 SK_RUN_FILTER(ppp->pass_filter, skb) == 0) {
1841 if (ppp->debug & 1)
1842 netdev_printk(KERN_DEBUG, ppp->dev,
1843 "PPP: inbound frame "
1844 "not passed\n");
1845 kfree_skb(skb);
1846 return;
1847 }
1848 if (!(ppp->active_filter &&
1849 SK_RUN_FILTER(ppp->active_filter, skb) == 0))
1850 ppp->last_recv = jiffies;
1851 __skb_pull(skb, 2);
1852 } else
1853 #endif /* CONFIG_PPP_FILTER */
1854 ppp->last_recv = jiffies;
1855
1856 if ((ppp->dev->flags & IFF_UP) == 0 ||
1857 ppp->npmode[npi] != NPMODE_PASS) {
1858 kfree_skb(skb);
1859 } else {
1860 /* chop off protocol */
1861 skb_pull_rcsum(skb, 2);
1862 skb->dev = ppp->dev;
1863 skb->protocol = htons(npindex_to_ethertype[npi]);
1864 skb_reset_mac_header(skb);
1865 netif_rx(skb);
1866 }
1867 }
1868 return;
1869
1870 err:
1871 kfree_skb(skb);
1872 ppp_receive_error(ppp);
1873 }
1874
1875 static struct sk_buff *
1876 ppp_decompress_frame(struct ppp *ppp, struct sk_buff *skb)
1877 {
1878 int proto = PPP_PROTO(skb);
1879 struct sk_buff *ns;
1880 int len;
1881
1882 /* Until we fix all the decompressor's need to make sure
1883 * data portion is linear.
1884 */
1885 if (!pskb_may_pull(skb, skb->len))
1886 goto err;
1887
1888 if (proto == PPP_COMP) {
1889 int obuff_size;
1890
1891 switch(ppp->rcomp->compress_proto) {
1892 case CI_MPPE:
1893 obuff_size = ppp->mru + PPP_HDRLEN + 1;
1894 break;
1895 default:
1896 obuff_size = ppp->mru + PPP_HDRLEN;
1897 break;
1898 }
1899
1900 ns = dev_alloc_skb(obuff_size);
1901 if (!ns) {
1902 netdev_err(ppp->dev, "ppp_decompress_frame: "
1903 "no memory\n");
1904 goto err;
1905 }
1906 /* the decompressor still expects the A/C bytes in the hdr */
1907 len = ppp->rcomp->decompress(ppp->rc_state, skb->data - 2,
1908 skb->len + 2, ns->data, obuff_size);
1909 if (len < 0) {
1910 /* Pass the compressed frame to pppd as an
1911 error indication. */
1912 if (len == DECOMP_FATALERROR)
1913 ppp->rstate |= SC_DC_FERROR;
1914 kfree_skb(ns);
1915 goto err;
1916 }
1917
1918 consume_skb(skb);
1919 skb = ns;
1920 skb_put(skb, len);
1921 skb_pull(skb, 2); /* pull off the A/C bytes */
1922
1923 } else {
1924 /* Uncompressed frame - pass to decompressor so it
1925 can update its dictionary if necessary. */
1926 if (ppp->rcomp->incomp)
1927 ppp->rcomp->incomp(ppp->rc_state, skb->data - 2,
1928 skb->len + 2);
1929 }
1930
1931 return skb;
1932
1933 err:
1934 ppp->rstate |= SC_DC_ERROR;
1935 ppp_receive_error(ppp);
1936 return skb;
1937 }
1938
1939 #ifdef CONFIG_PPP_MULTILINK
1940 /*
1941 * Receive a multilink frame.
1942 * We put it on the reconstruction queue and then pull off
1943 * as many completed frames as we can.
1944 */
1945 static void
1946 ppp_receive_mp_frame(struct ppp *ppp, struct sk_buff *skb, struct channel *pch)
1947 {
1948 u32 mask, seq;
1949 struct channel *ch;
1950 int mphdrlen = (ppp->flags & SC_MP_SHORTSEQ)? MPHDRLEN_SSN: MPHDRLEN;
1951
1952 if (!pskb_may_pull(skb, mphdrlen + 1) || ppp->mrru == 0)
1953 goto err; /* no good, throw it away */
1954
1955 /* Decode sequence number and begin/end bits */
1956 if (ppp->flags & SC_MP_SHORTSEQ) {
1957 seq = ((skb->data[2] & 0x0f) << 8) | skb->data[3];
1958 mask = 0xfff;
1959 } else {
1960 seq = (skb->data[3] << 16) | (skb->data[4] << 8)| skb->data[5];
1961 mask = 0xffffff;
1962 }
1963 PPP_MP_CB(skb)->BEbits = skb->data[2];
1964 skb_pull(skb, mphdrlen); /* pull off PPP and MP headers */
1965
1966 /*
1967 * Do protocol ID decompression on the first fragment of each packet.
1968 */
1969 if ((PPP_MP_CB(skb)->BEbits & B) && (skb->data[0] & 1))
1970 *skb_push(skb, 1) = 0;
1971
1972 /*
1973 * Expand sequence number to 32 bits, making it as close
1974 * as possible to ppp->minseq.
1975 */
1976 seq |= ppp->minseq & ~mask;
1977 if ((int)(ppp->minseq - seq) > (int)(mask >> 1))
1978 seq += mask + 1;
1979 else if ((int)(seq - ppp->minseq) > (int)(mask >> 1))
1980 seq -= mask + 1; /* should never happen */
1981 PPP_MP_CB(skb)->sequence = seq;
1982 pch->lastseq = seq;
1983
1984 /*
1985 * If this packet comes before the next one we were expecting,
1986 * drop it.
1987 */
1988 if (seq_before(seq, ppp->nextseq)) {
1989 kfree_skb(skb);
1990 ++ppp->dev->stats.rx_dropped;
1991 ppp_receive_error(ppp);
1992 return;
1993 }
1994
1995 /*
1996 * Reevaluate minseq, the minimum over all channels of the
1997 * last sequence number received on each channel. Because of
1998 * the increasing sequence number rule, we know that any fragment
1999 * before `minseq' which hasn't arrived is never going to arrive.
2000 * The list of channels can't change because we have the receive
2001 * side of the ppp unit locked.
2002 */
2003 list_for_each_entry(ch, &ppp->channels, clist) {
2004 if (seq_before(ch->lastseq, seq))
2005 seq = ch->lastseq;
2006 }
2007 if (seq_before(ppp->minseq, seq))
2008 ppp->minseq = seq;
2009
2010 /* Put the fragment on the reconstruction queue */
2011 ppp_mp_insert(ppp, skb);
2012
2013 /* If the queue is getting long, don't wait any longer for packets
2014 before the start of the queue. */
2015 if (skb_queue_len(&ppp->mrq) >= PPP_MP_MAX_QLEN) {
2016 struct sk_buff *mskb = skb_peek(&ppp->mrq);
2017 if (seq_before(ppp->minseq, PPP_MP_CB(mskb)->sequence))
2018 ppp->minseq = PPP_MP_CB(mskb)->sequence;
2019 }
2020
2021 /* Pull completed packets off the queue and receive them. */
2022 while ((skb = ppp_mp_reconstruct(ppp))) {
2023 if (pskb_may_pull(skb, 2))
2024 ppp_receive_nonmp_frame(ppp, skb);
2025 else {
2026 ++ppp->dev->stats.rx_length_errors;
2027 kfree_skb(skb);
2028 ppp_receive_error(ppp);
2029 }
2030 }
2031
2032 return;
2033
2034 err:
2035 kfree_skb(skb);
2036 ppp_receive_error(ppp);
2037 }
2038
2039 /*
2040 * Insert a fragment on the MP reconstruction queue.
2041 * The queue is ordered by increasing sequence number.
2042 */
2043 static void
2044 ppp_mp_insert(struct ppp *ppp, struct sk_buff *skb)
2045 {
2046 struct sk_buff *p;
2047 struct sk_buff_head *list = &ppp->mrq;
2048 u32 seq = PPP_MP_CB(skb)->sequence;
2049
2050 /* N.B. we don't need to lock the list lock because we have the
2051 ppp unit receive-side lock. */
2052 skb_queue_walk(list, p) {
2053 if (seq_before(seq, PPP_MP_CB(p)->sequence))
2054 break;
2055 }
2056 __skb_queue_before(list, p, skb);
2057 }
2058
2059 /*
2060 * Reconstruct a packet from the MP fragment queue.
2061 * We go through increasing sequence numbers until we find a
2062 * complete packet, or we get to the sequence number for a fragment
2063 * which hasn't arrived but might still do so.
2064 */
2065 static struct sk_buff *
2066 ppp_mp_reconstruct(struct ppp *ppp)
2067 {
2068 u32 seq = ppp->nextseq;
2069 u32 minseq = ppp->minseq;
2070 struct sk_buff_head *list = &ppp->mrq;
2071 struct sk_buff *p, *tmp;
2072 struct sk_buff *head, *tail;
2073 struct sk_buff *skb = NULL;
2074 int lost = 0, len = 0;
2075
2076 if (ppp->mrru == 0) /* do nothing until mrru is set */
2077 return NULL;
2078 head = list->next;
2079 tail = NULL;
2080 skb_queue_walk_safe(list, p, tmp) {
2081 again:
2082 if (seq_before(PPP_MP_CB(p)->sequence, seq)) {
2083 /* this can't happen, anyway ignore the skb */
2084 netdev_err(ppp->dev, "ppp_mp_reconstruct bad "
2085 "seq %u < %u\n",
2086 PPP_MP_CB(p)->sequence, seq);
2087 __skb_unlink(p, list);
2088 kfree_skb(p);
2089 continue;
2090 }
2091 if (PPP_MP_CB(p)->sequence != seq) {
2092 u32 oldseq;
2093 /* Fragment `seq' is missing. If it is after
2094 minseq, it might arrive later, so stop here. */
2095 if (seq_after(seq, minseq))
2096 break;
2097 /* Fragment `seq' is lost, keep going. */
2098 lost = 1;
2099 oldseq = seq;
2100 seq = seq_before(minseq, PPP_MP_CB(p)->sequence)?
2101 minseq + 1: PPP_MP_CB(p)->sequence;
2102
2103 if (ppp->debug & 1)
2104 netdev_printk(KERN_DEBUG, ppp->dev,
2105 "lost frag %u..%u\n",
2106 oldseq, seq-1);
2107
2108 goto again;
2109 }
2110
2111 /*
2112 * At this point we know that all the fragments from
2113 * ppp->nextseq to seq are either present or lost.
2114 * Also, there are no complete packets in the queue
2115 * that have no missing fragments and end before this
2116 * fragment.
2117 */
2118
2119 /* B bit set indicates this fragment starts a packet */
2120 if (PPP_MP_CB(p)->BEbits & B) {
2121 head = p;
2122 lost = 0;
2123 len = 0;
2124 }
2125
2126 len += p->len;
2127
2128 /* Got a complete packet yet? */
2129 if (lost == 0 && (PPP_MP_CB(p)->BEbits & E) &&
2130 (PPP_MP_CB(head)->BEbits & B)) {
2131 if (len > ppp->mrru + 2) {
2132 ++ppp->dev->stats.rx_length_errors;
2133 netdev_printk(KERN_DEBUG, ppp->dev,
2134 "PPP: reconstructed packet"
2135 " is too long (%d)\n", len);
2136 } else {
2137 tail = p;
2138 break;
2139 }
2140 ppp->nextseq = seq + 1;
2141 }
2142
2143 /*
2144 * If this is the ending fragment of a packet,
2145 * and we haven't found a complete valid packet yet,
2146 * we can discard up to and including this fragment.
2147 */
2148 if (PPP_MP_CB(p)->BEbits & E) {
2149 struct sk_buff *tmp2;
2150
2151 skb_queue_reverse_walk_from_safe(list, p, tmp2) {
2152 if (ppp->debug & 1)
2153 netdev_printk(KERN_DEBUG, ppp->dev,
2154 "discarding frag %u\n",
2155 PPP_MP_CB(p)->sequence);
2156 __skb_unlink(p, list);
2157 kfree_skb(p);
2158 }
2159 head = skb_peek(list);
2160 if (!head)
2161 break;
2162 }
2163 ++seq;
2164 }
2165
2166 /* If we have a complete packet, copy it all into one skb. */
2167 if (tail != NULL) {
2168 /* If we have discarded any fragments,
2169 signal a receive error. */
2170 if (PPP_MP_CB(head)->sequence != ppp->nextseq) {
2171 skb_queue_walk_safe(list, p, tmp) {
2172 if (p == head)
2173 break;
2174 if (ppp->debug & 1)
2175 netdev_printk(KERN_DEBUG, ppp->dev,
2176 "discarding frag %u\n",
2177 PPP_MP_CB(p)->sequence);
2178 __skb_unlink(p, list);
2179 kfree_skb(p);
2180 }
2181
2182 if (ppp->debug & 1)
2183 netdev_printk(KERN_DEBUG, ppp->dev,
2184 " missed pkts %u..%u\n",
2185 ppp->nextseq,
2186 PPP_MP_CB(head)->sequence-1);
2187 ++ppp->dev->stats.rx_dropped;
2188 ppp_receive_error(ppp);
2189 }
2190
2191 skb = head;
2192 if (head != tail) {
2193 struct sk_buff **fragpp = &skb_shinfo(skb)->frag_list;
2194 p = skb_queue_next(list, head);
2195 __skb_unlink(skb, list);
2196 skb_queue_walk_from_safe(list, p, tmp) {
2197 __skb_unlink(p, list);
2198 *fragpp = p;
2199 p->next = NULL;
2200 fragpp = &p->next;
2201
2202 skb->len += p->len;
2203 skb->data_len += p->len;
2204 skb->truesize += p->truesize;
2205
2206 if (p == tail)
2207 break;
2208 }
2209 } else {
2210 __skb_unlink(skb, list);
2211 }
2212
2213 ppp->nextseq = PPP_MP_CB(tail)->sequence + 1;
2214 }
2215
2216 return skb;
2217 }
2218 #endif /* CONFIG_PPP_MULTILINK */
2219
2220 /*
2221 * Channel interface.
2222 */
2223
2224 /* Create a new, unattached ppp channel. */
2225 int ppp_register_channel(struct ppp_channel *chan)
2226 {
2227 return ppp_register_net_channel(current->nsproxy->net_ns, chan);
2228 }
2229
2230 /* Create a new, unattached ppp channel for specified net. */
2231 int ppp_register_net_channel(struct net *net, struct ppp_channel *chan)
2232 {
2233 struct channel *pch;
2234 struct ppp_net *pn;
2235
2236 pch = kzalloc(sizeof(struct channel), GFP_KERNEL);
2237 if (!pch)
2238 return -ENOMEM;
2239
2240 pn = ppp_pernet(net);
2241
2242 pch->ppp = NULL;
2243 pch->chan = chan;
2244 pch->chan_net = get_net(net);
2245 chan->ppp = pch;
2246 init_ppp_file(&pch->file, CHANNEL);
2247 pch->file.hdrlen = chan->hdrlen;
2248 #ifdef CONFIG_PPP_MULTILINK
2249 pch->lastseq = -1;
2250 #endif /* CONFIG_PPP_MULTILINK */
2251 init_rwsem(&pch->chan_sem);
2252 spin_lock_init(&pch->downl);
2253 rwlock_init(&pch->upl);
2254
2255 spin_lock_bh(&pn->all_channels_lock);
2256 pch->file.index = ++pn->last_channel_index;
2257 list_add(&pch->list, &pn->new_channels);
2258 atomic_inc(&channel_count);
2259 spin_unlock_bh(&pn->all_channels_lock);
2260
2261 return 0;
2262 }
2263
2264 /*
2265 * Return the index of a channel.
2266 */
2267 int ppp_channel_index(struct ppp_channel *chan)
2268 {
2269 struct channel *pch = chan->ppp;
2270
2271 if (pch)
2272 return pch->file.index;
2273 return -1;
2274 }
2275
2276 /*
2277 * Return the PPP unit number to which a channel is connected.
2278 */
2279 int ppp_unit_number(struct ppp_channel *chan)
2280 {
2281 struct channel *pch = chan->ppp;
2282 int unit = -1;
2283
2284 if (pch) {
2285 read_lock_bh(&pch->upl);
2286 if (pch->ppp)
2287 unit = pch->ppp->file.index;
2288 read_unlock_bh(&pch->upl);
2289 }
2290 return unit;
2291 }
2292
2293 /*
2294 * Return the PPP device interface name of a channel.
2295 */
2296 char *ppp_dev_name(struct ppp_channel *chan)
2297 {
2298 struct channel *pch = chan->ppp;
2299 char *name = NULL;
2300
2301 if (pch) {
2302 read_lock_bh(&pch->upl);
2303 if (pch->ppp && pch->ppp->dev)
2304 name = pch->ppp->dev->name;
2305 read_unlock_bh(&pch->upl);
2306 }
2307 return name;
2308 }
2309
2310
2311 /*
2312 * Disconnect a channel from the generic layer.
2313 * This must be called in process context.
2314 */
2315 void
2316 ppp_unregister_channel(struct ppp_channel *chan)
2317 {
2318 struct channel *pch = chan->ppp;
2319 struct ppp_net *pn;
2320
2321 if (!pch)
2322 return; /* should never happen */
2323
2324 chan->ppp = NULL;
2325
2326 /*
2327 * This ensures that we have returned from any calls into the
2328 * the channel's start_xmit or ioctl routine before we proceed.
2329 */
2330 down_write(&pch->chan_sem);
2331 spin_lock_bh(&pch->downl);
2332 pch->chan = NULL;
2333 spin_unlock_bh(&pch->downl);
2334 up_write(&pch->chan_sem);
2335 ppp_disconnect_channel(pch);
2336
2337 pn = ppp_pernet(pch->chan_net);
2338 spin_lock_bh(&pn->all_channels_lock);
2339 list_del(&pch->list);
2340 spin_unlock_bh(&pn->all_channels_lock);
2341 put_net(pch->chan_net);
2342 pch->chan_net = NULL;
2343
2344 pch->file.dead = 1;
2345 wake_up_interruptible(&pch->file.rwait);
2346 if (atomic_dec_and_test(&pch->file.refcnt))
2347 ppp_destroy_channel(pch);
2348 }
2349
2350 /*
2351 * Callback from a channel when it can accept more to transmit.
2352 * This should be called at BH/softirq level, not interrupt level.
2353 */
2354 void
2355 ppp_output_wakeup(struct ppp_channel *chan)
2356 {
2357 struct channel *pch = chan->ppp;
2358
2359 if (!pch)
2360 return;
2361 ppp_channel_push(pch);
2362 }
2363
2364 /*
2365 * Compression control.
2366 */
2367
2368 /* Process the PPPIOCSCOMPRESS ioctl. */
2369 static int
2370 ppp_set_compress(struct ppp *ppp, unsigned long arg)
2371 {
2372 int err;
2373 struct compressor *cp, *ocomp;
2374 struct ppp_option_data data;
2375 void *state, *ostate;
2376 unsigned char ccp_option[CCP_MAX_OPTION_LENGTH];
2377
2378 err = -EFAULT;
2379 if (copy_from_user(&data, (void __user *) arg, sizeof(data)) ||
2380 (data.length <= CCP_MAX_OPTION_LENGTH &&
2381 copy_from_user(ccp_option, (void __user *) data.ptr, data.length)))
2382 goto out;
2383 err = -EINVAL;
2384 if (data.length > CCP_MAX_OPTION_LENGTH ||
2385 ccp_option[1] < 2 || ccp_option[1] > data.length)
2386 goto out;
2387
2388 cp = try_then_request_module(
2389 find_compressor(ccp_option[0]),
2390 "ppp-compress-%d", ccp_option[0]);
2391 if (!cp)
2392 goto out;
2393
2394 err = -ENOBUFS;
2395 if (data.transmit) {
2396 state = cp->comp_alloc(ccp_option, data.length);
2397 if (state) {
2398 ppp_xmit_lock(ppp);
2399 ppp->xstate &= ~SC_COMP_RUN;
2400 ocomp = ppp->xcomp;
2401 ostate = ppp->xc_state;
2402 ppp->xcomp = cp;
2403 ppp->xc_state = state;
2404 ppp_xmit_unlock(ppp);
2405 if (ostate) {
2406 ocomp->comp_free(ostate);
2407 module_put(ocomp->owner);
2408 }
2409 err = 0;
2410 } else
2411 module_put(cp->owner);
2412
2413 } else {
2414 state = cp->decomp_alloc(ccp_option, data.length);
2415 if (state) {
2416 ppp_recv_lock(ppp);
2417 ppp->rstate &= ~SC_DECOMP_RUN;
2418 ocomp = ppp->rcomp;
2419 ostate = ppp->rc_state;
2420 ppp->rcomp = cp;
2421 ppp->rc_state = state;
2422 ppp_recv_unlock(ppp);
2423 if (ostate) {
2424 ocomp->decomp_free(ostate);
2425 module_put(ocomp->owner);
2426 }
2427 err = 0;
2428 } else
2429 module_put(cp->owner);
2430 }
2431
2432 out:
2433 return err;
2434 }
2435
2436 /*
2437 * Look at a CCP packet and update our state accordingly.
2438 * We assume the caller has the xmit or recv path locked.
2439 */
2440 static void
2441 ppp_ccp_peek(struct ppp *ppp, struct sk_buff *skb, int inbound)
2442 {
2443 unsigned char *dp;
2444 int len;
2445
2446 if (!pskb_may_pull(skb, CCP_HDRLEN + 2))
2447 return; /* no header */
2448 dp = skb->data + 2;
2449
2450 switch (CCP_CODE(dp)) {
2451 case CCP_CONFREQ:
2452
2453 /* A ConfReq starts negotiation of compression
2454 * in one direction of transmission,
2455 * and hence brings it down...but which way?
2456 *
2457 * Remember:
2458 * A ConfReq indicates what the sender would like to receive
2459 */
2460 if(inbound)
2461 /* He is proposing what I should send */
2462 ppp->xstate &= ~SC_COMP_RUN;
2463 else
2464 /* I am proposing to what he should send */
2465 ppp->rstate &= ~SC_DECOMP_RUN;
2466
2467 break;
2468
2469 case CCP_TERMREQ:
2470 case CCP_TERMACK:
2471 /*
2472 * CCP is going down, both directions of transmission
2473 */
2474 ppp->rstate &= ~SC_DECOMP_RUN;
2475 ppp->xstate &= ~SC_COMP_RUN;
2476 break;
2477
2478 case CCP_CONFACK:
2479 if ((ppp->flags & (SC_CCP_OPEN | SC_CCP_UP)) != SC_CCP_OPEN)
2480 break;
2481 len = CCP_LENGTH(dp);
2482 if (!pskb_may_pull(skb, len + 2))
2483 return; /* too short */
2484 dp += CCP_HDRLEN;
2485 len -= CCP_HDRLEN;
2486 if (len < CCP_OPT_MINLEN || len < CCP_OPT_LENGTH(dp))
2487 break;
2488 if (inbound) {
2489 /* we will start receiving compressed packets */
2490 if (!ppp->rc_state)
2491 break;
2492 if (ppp->rcomp->decomp_init(ppp->rc_state, dp, len,
2493 ppp->file.index, 0, ppp->mru, ppp->debug)) {
2494 ppp->rstate |= SC_DECOMP_RUN;
2495 ppp->rstate &= ~(SC_DC_ERROR | SC_DC_FERROR);
2496 }
2497 } else {
2498 /* we will soon start sending compressed packets */
2499 if (!ppp->xc_state)
2500 break;
2501 if (ppp->xcomp->comp_init(ppp->xc_state, dp, len,
2502 ppp->file.index, 0, ppp->debug))
2503 ppp->xstate |= SC_COMP_RUN;
2504 }
2505 break;
2506
2507 case CCP_RESETACK:
2508 /* reset the [de]compressor */
2509 if ((ppp->flags & SC_CCP_UP) == 0)
2510 break;
2511 if (inbound) {
2512 if (ppp->rc_state && (ppp->rstate & SC_DECOMP_RUN)) {
2513 ppp->rcomp->decomp_reset(ppp->rc_state);
2514 ppp->rstate &= ~SC_DC_ERROR;
2515 }
2516 } else {
2517 if (ppp->xc_state && (ppp->xstate & SC_COMP_RUN))
2518 ppp->xcomp->comp_reset(ppp->xc_state);
2519 }
2520 break;
2521 }
2522 }
2523
2524 /* Free up compression resources. */
2525 static void
2526 ppp_ccp_closed(struct ppp *ppp)
2527 {
2528 void *xstate, *rstate;
2529 struct compressor *xcomp, *rcomp;
2530
2531 ppp_lock(ppp);
2532 ppp->flags &= ~(SC_CCP_OPEN | SC_CCP_UP);
2533 ppp->xstate = 0;
2534 xcomp = ppp->xcomp;
2535 xstate = ppp->xc_state;
2536 ppp->xc_state = NULL;
2537 ppp->rstate = 0;
2538 rcomp = ppp->rcomp;
2539 rstate = ppp->rc_state;
2540 ppp->rc_state = NULL;
2541 ppp_unlock(ppp);
2542
2543 if (xstate) {
2544 xcomp->comp_free(xstate);
2545 module_put(xcomp->owner);
2546 }
2547 if (rstate) {
2548 rcomp->decomp_free(rstate);
2549 module_put(rcomp->owner);
2550 }
2551 }
2552
2553 /* List of compressors. */
2554 static LIST_HEAD(compressor_list);
2555 static DEFINE_SPINLOCK(compressor_list_lock);
2556
2557 struct compressor_entry {
2558 struct list_head list;
2559 struct compressor *comp;
2560 };
2561
2562 static struct compressor_entry *
2563 find_comp_entry(int proto)
2564 {
2565 struct compressor_entry *ce;
2566
2567 list_for_each_entry(ce, &compressor_list, list) {
2568 if (ce->comp->compress_proto == proto)
2569 return ce;
2570 }
2571 return NULL;
2572 }
2573
2574 /* Register a compressor */
2575 int
2576 ppp_register_compressor(struct compressor *cp)
2577 {
2578 struct compressor_entry *ce;
2579 int ret;
2580 spin_lock(&compressor_list_lock);
2581 ret = -EEXIST;
2582 if (find_comp_entry(cp->compress_proto))
2583 goto out;
2584 ret = -ENOMEM;
2585 ce = kmalloc(sizeof(struct compressor_entry), GFP_ATOMIC);
2586 if (!ce)
2587 goto out;
2588 ret = 0;
2589 ce->comp = cp;
2590 list_add(&ce->list, &compressor_list);
2591 out:
2592 spin_unlock(&compressor_list_lock);
2593 return ret;
2594 }
2595
2596 /* Unregister a compressor */
2597 void
2598 ppp_unregister_compressor(struct compressor *cp)
2599 {
2600 struct compressor_entry *ce;
2601
2602 spin_lock(&compressor_list_lock);
2603 ce = find_comp_entry(cp->compress_proto);
2604 if (ce && ce->comp == cp) {
2605 list_del(&ce->list);
2606 kfree(ce);
2607 }
2608 spin_unlock(&compressor_list_lock);
2609 }
2610
2611 /* Find a compressor. */
2612 static struct compressor *
2613 find_compressor(int type)
2614 {
2615 struct compressor_entry *ce;
2616 struct compressor *cp = NULL;
2617
2618 spin_lock(&compressor_list_lock);
2619 ce = find_comp_entry(type);
2620 if (ce) {
2621 cp = ce->comp;
2622 if (!try_module_get(cp->owner))
2623 cp = NULL;
2624 }
2625 spin_unlock(&compressor_list_lock);
2626 return cp;
2627 }
2628
2629 /*
2630 * Miscelleneous stuff.
2631 */
2632
2633 static void
2634 ppp_get_stats(struct ppp *ppp, struct ppp_stats *st)
2635 {
2636 struct slcompress *vj = ppp->vj;
2637
2638 memset(st, 0, sizeof(*st));
2639 st->p.ppp_ipackets = ppp->stats64.rx_packets;
2640 st->p.ppp_ierrors = ppp->dev->stats.rx_errors;
2641 st->p.ppp_ibytes = ppp->stats64.rx_bytes;
2642 st->p.ppp_opackets = ppp->stats64.tx_packets;
2643 st->p.ppp_oerrors = ppp->dev->stats.tx_errors;
2644 st->p.ppp_obytes = ppp->stats64.tx_bytes;
2645 if (!vj)
2646 return;
2647 st->vj.vjs_packets = vj->sls_o_compressed + vj->sls_o_uncompressed;
2648 st->vj.vjs_compressed = vj->sls_o_compressed;
2649 st->vj.vjs_searches = vj->sls_o_searches;
2650 st->vj.vjs_misses = vj->sls_o_misses;
2651 st->vj.vjs_errorin = vj->sls_i_error;
2652 st->vj.vjs_tossed = vj->sls_i_tossed;
2653 st->vj.vjs_uncompressedin = vj->sls_i_uncompressed;
2654 st->vj.vjs_compressedin = vj->sls_i_compressed;
2655 }
2656
2657 /*
2658 * Stuff for handling the lists of ppp units and channels
2659 * and for initialization.
2660 */
2661
2662 /*
2663 * Create a new ppp interface unit. Fails if it can't allocate memory
2664 * or if there is already a unit with the requested number.
2665 * unit == -1 means allocate a new number.
2666 */
2667 static struct ppp *
2668 ppp_create_interface(struct net *net, int unit, int *retp)
2669 {
2670 struct ppp *ppp;
2671 struct ppp_net *pn;
2672 struct net_device *dev = NULL;
2673 int ret = -ENOMEM;
2674 int i;
2675
2676 dev = alloc_netdev(sizeof(struct ppp), "", ppp_setup);
2677 if (!dev)
2678 goto out1;
2679
2680 pn = ppp_pernet(net);
2681
2682 ppp = netdev_priv(dev);
2683 ppp->dev = dev;
2684 ppp->mru = PPP_MRU;
2685 init_ppp_file(&ppp->file, INTERFACE);
2686 ppp->file.hdrlen = PPP_HDRLEN - 2; /* don't count proto bytes */
2687 for (i = 0; i < NUM_NP; ++i)
2688 ppp->npmode[i] = NPMODE_PASS;
2689 INIT_LIST_HEAD(&ppp->channels);
2690 spin_lock_init(&ppp->rlock);
2691 spin_lock_init(&ppp->wlock);
2692 #ifdef CONFIG_PPP_MULTILINK
2693 ppp->minseq = -1;
2694 skb_queue_head_init(&ppp->mrq);
2695 #endif /* CONFIG_PPP_MULTILINK */
2696 #ifdef CONFIG_PPP_FILTER
2697 ppp->pass_filter = NULL;
2698 ppp->active_filter = NULL;
2699 #endif /* CONFIG_PPP_FILTER */
2700
2701 /*
2702 * drum roll: don't forget to set
2703 * the net device is belong to
2704 */
2705 dev_net_set(dev, net);
2706
2707 mutex_lock(&pn->all_ppp_mutex);
2708
2709 if (unit < 0) {
2710 unit = unit_get(&pn->units_idr, ppp);
2711 if (unit < 0) {
2712 ret = unit;
2713 goto out2;
2714 }
2715 } else {
2716 ret = -EEXIST;
2717 if (unit_find(&pn->units_idr, unit))
2718 goto out2; /* unit already exists */
2719 /*
2720 * if caller need a specified unit number
2721 * lets try to satisfy him, otherwise --
2722 * he should better ask us for new unit number
2723 *
2724 * NOTE: yes I know that returning EEXIST it's not
2725 * fair but at least pppd will ask us to allocate
2726 * new unit in this case so user is happy :)
2727 */
2728 unit = unit_set(&pn->units_idr, ppp, unit);
2729 if (unit < 0)
2730 goto out2;
2731 }
2732
2733 /* Initialize the new ppp unit */
2734 ppp->file.index = unit;
2735 sprintf(dev->name, "ppp%d", unit);
2736
2737 ret = register_netdev(dev);
2738 if (ret != 0) {
2739 unit_put(&pn->units_idr, unit);
2740 netdev_err(ppp->dev, "PPP: couldn't register device %s (%d)\n",
2741 dev->name, ret);
2742 goto out2;
2743 }
2744
2745 ppp->ppp_net = net;
2746
2747 atomic_inc(&ppp_unit_count);
2748 mutex_unlock(&pn->all_ppp_mutex);
2749
2750 *retp = 0;
2751 return ppp;
2752
2753 out2:
2754 mutex_unlock(&pn->all_ppp_mutex);
2755 free_netdev(dev);
2756 out1:
2757 *retp = ret;
2758 return NULL;
2759 }
2760
2761 /*
2762 * Initialize a ppp_file structure.
2763 */
2764 static void
2765 init_ppp_file(struct ppp_file *pf, int kind)
2766 {
2767 pf->kind = kind;
2768 skb_queue_head_init(&pf->xq);
2769 skb_queue_head_init(&pf->rq);
2770 atomic_set(&pf->refcnt, 1);
2771 init_waitqueue_head(&pf->rwait);
2772 }
2773
2774 /*
2775 * Take down a ppp interface unit - called when the owning file
2776 * (the one that created the unit) is closed or detached.
2777 */
2778 static void ppp_shutdown_interface(struct ppp *ppp)
2779 {
2780 struct ppp_net *pn;
2781
2782 pn = ppp_pernet(ppp->ppp_net);
2783 mutex_lock(&pn->all_ppp_mutex);
2784
2785 /* This will call dev_close() for us. */
2786 ppp_lock(ppp);
2787 if (!ppp->closing) {
2788 ppp->closing = 1;
2789 ppp_unlock(ppp);
2790 unregister_netdev(ppp->dev);
2791 unit_put(&pn->units_idr, ppp->file.index);
2792 } else
2793 ppp_unlock(ppp);
2794
2795 ppp->file.dead = 1;
2796 ppp->owner = NULL;
2797 wake_up_interruptible(&ppp->file.rwait);
2798
2799 mutex_unlock(&pn->all_ppp_mutex);
2800 }
2801
2802 /*
2803 * Free the memory used by a ppp unit. This is only called once
2804 * there are no channels connected to the unit and no file structs
2805 * that reference the unit.
2806 */
2807 static void ppp_destroy_interface(struct ppp *ppp)
2808 {
2809 atomic_dec(&ppp_unit_count);
2810
2811 if (!ppp->file.dead || ppp->n_channels) {
2812 /* "can't happen" */
2813 netdev_err(ppp->dev, "ppp: destroying ppp struct %p "
2814 "but dead=%d n_channels=%d !\n",
2815 ppp, ppp->file.dead, ppp->n_channels);
2816 return;
2817 }
2818
2819 ppp_ccp_closed(ppp);
2820 if (ppp->vj) {
2821 slhc_free(ppp->vj);
2822 ppp->vj = NULL;
2823 }
2824 skb_queue_purge(&ppp->file.xq);
2825 skb_queue_purge(&ppp->file.rq);
2826 #ifdef CONFIG_PPP_MULTILINK
2827 skb_queue_purge(&ppp->mrq);
2828 #endif /* CONFIG_PPP_MULTILINK */
2829 #ifdef CONFIG_PPP_FILTER
2830 if (ppp->pass_filter) {
2831 sk_unattached_filter_destroy(ppp->pass_filter);
2832 ppp->pass_filter = NULL;
2833 }
2834
2835 if (ppp->active_filter) {
2836 sk_unattached_filter_destroy(ppp->active_filter);
2837 ppp->active_filter = NULL;
2838 }
2839 #endif /* CONFIG_PPP_FILTER */
2840
2841 kfree_skb(ppp->xmit_pending);
2842
2843 free_netdev(ppp->dev);
2844 }
2845
2846 /*
2847 * Locate an existing ppp unit.
2848 * The caller should have locked the all_ppp_mutex.
2849 */
2850 static struct ppp *
2851 ppp_find_unit(struct ppp_net *pn, int unit)
2852 {
2853 return unit_find(&pn->units_idr, unit);
2854 }
2855
2856 /*
2857 * Locate an existing ppp channel.
2858 * The caller should have locked the all_channels_lock.
2859 * First we look in the new_channels list, then in the
2860 * all_channels list. If found in the new_channels list,
2861 * we move it to the all_channels list. This is for speed
2862 * when we have a lot of channels in use.
2863 */
2864 static struct channel *
2865 ppp_find_channel(struct ppp_net *pn, int unit)
2866 {
2867 struct channel *pch;
2868
2869 list_for_each_entry(pch, &pn->new_channels, list) {
2870 if (pch->file.index == unit) {
2871 list_move(&pch->list, &pn->all_channels);
2872 return pch;
2873 }
2874 }
2875
2876 list_for_each_entry(pch, &pn->all_channels, list) {
2877 if (pch->file.index == unit)
2878 return pch;
2879 }
2880
2881 return NULL;
2882 }
2883
2884 /*
2885 * Connect a PPP channel to a PPP interface unit.
2886 */
2887 static int
2888 ppp_connect_channel(struct channel *pch, int unit)
2889 {
2890 struct ppp *ppp;
2891 struct ppp_net *pn;
2892 int ret = -ENXIO;
2893 int hdrlen;
2894
2895 pn = ppp_pernet(pch->chan_net);
2896
2897 mutex_lock(&pn->all_ppp_mutex);
2898 ppp = ppp_find_unit(pn, unit);
2899 if (!ppp)
2900 goto out;
2901 write_lock_bh(&pch->upl);
2902 ret = -EINVAL;
2903 if (pch->ppp)
2904 goto outl;
2905
2906 ppp_lock(ppp);
2907 if (pch->file.hdrlen > ppp->file.hdrlen)
2908 ppp->file.hdrlen = pch->file.hdrlen;
2909 hdrlen = pch->file.hdrlen + 2; /* for protocol bytes */
2910 if (hdrlen > ppp->dev->hard_header_len)
2911 ppp->dev->hard_header_len = hdrlen;
2912 list_add_tail(&pch->clist, &ppp->channels);
2913 ++ppp->n_channels;
2914 pch->ppp = ppp;
2915 atomic_inc(&ppp->file.refcnt);
2916 ppp_unlock(ppp);
2917 ret = 0;
2918
2919 outl:
2920 write_unlock_bh(&pch->upl);
2921 out:
2922 mutex_unlock(&pn->all_ppp_mutex);
2923 return ret;
2924 }
2925
2926 /*
2927 * Disconnect a channel from its ppp unit.
2928 */
2929 static int
2930 ppp_disconnect_channel(struct channel *pch)
2931 {
2932 struct ppp *ppp;
2933 int err = -EINVAL;
2934
2935 write_lock_bh(&pch->upl);
2936 ppp = pch->ppp;
2937 pch->ppp = NULL;
2938 write_unlock_bh(&pch->upl);
2939 if (ppp) {
2940 /* remove it from the ppp unit's list */
2941 ppp_lock(ppp);
2942 list_del(&pch->clist);
2943 if (--ppp->n_channels == 0)
2944 wake_up_interruptible(&ppp->file.rwait);
2945 ppp_unlock(ppp);
2946 if (atomic_dec_and_test(&ppp->file.refcnt))
2947 ppp_destroy_interface(ppp);
2948 err = 0;
2949 }
2950 return err;
2951 }
2952
2953 /*
2954 * Free up the resources used by a ppp channel.
2955 */
2956 static void ppp_destroy_channel(struct channel *pch)
2957 {
2958 atomic_dec(&channel_count);
2959
2960 if (!pch->file.dead) {
2961 /* "can't happen" */
2962 pr_err("ppp: destroying undead channel %p !\n", pch);
2963 return;
2964 }
2965 skb_queue_purge(&pch->file.xq);
2966 skb_queue_purge(&pch->file.rq);
2967 kfree(pch);
2968 }
2969
2970 static void __exit ppp_cleanup(void)
2971 {
2972 /* should never happen */
2973 if (atomic_read(&ppp_unit_count) || atomic_read(&channel_count))
2974 pr_err("PPP: removing module but units remain!\n");
2975 unregister_chrdev(PPP_MAJOR, "ppp");
2976 device_destroy(ppp_class, MKDEV(PPP_MAJOR, 0));
2977 class_destroy(ppp_class);
2978 unregister_pernet_device(&ppp_net_ops);
2979 }
2980
2981 /*
2982 * Units handling. Caller must protect concurrent access
2983 * by holding all_ppp_mutex
2984 */
2985
2986 /* associate pointer with specified number */
2987 static int unit_set(struct idr *p, void *ptr, int n)
2988 {
2989 int unit;
2990
2991 unit = idr_alloc(p, ptr, n, n + 1, GFP_KERNEL);
2992 if (unit == -ENOSPC)
2993 unit = -EINVAL;
2994 return unit;
2995 }
2996
2997 /* get new free unit number and associate pointer with it */
2998 static int unit_get(struct idr *p, void *ptr)
2999 {
3000 return idr_alloc(p, ptr, 0, 0, GFP_KERNEL);
3001 }
3002
3003 /* put unit number back to a pool */
3004 static void unit_put(struct idr *p, int n)
3005 {
3006 idr_remove(p, n);
3007 }
3008
3009 /* get pointer associated with the number */
3010 static void *unit_find(struct idr *p, int n)
3011 {
3012 return idr_find(p, n);
3013 }
3014
3015 /* Module/initialization stuff */
3016
3017 module_init(ppp_init);
3018 module_exit(ppp_cleanup);
3019
3020 EXPORT_SYMBOL(ppp_register_net_channel);
3021 EXPORT_SYMBOL(ppp_register_channel);
3022 EXPORT_SYMBOL(ppp_unregister_channel);
3023 EXPORT_SYMBOL(ppp_channel_index);
3024 EXPORT_SYMBOL(ppp_unit_number);
3025 EXPORT_SYMBOL(ppp_dev_name);
3026 EXPORT_SYMBOL(ppp_input);
3027 EXPORT_SYMBOL(ppp_input_error);
3028 EXPORT_SYMBOL(ppp_output_wakeup);
3029 EXPORT_SYMBOL(ppp_register_compressor);
3030 EXPORT_SYMBOL(ppp_unregister_compressor);
3031 MODULE_LICENSE("GPL");
3032 MODULE_ALIAS_CHARDEV(PPP_MAJOR, 0);
3033 MODULE_ALIAS("devname:ppp");
Linux with added FPC-III support