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net/mlx4_en: cq->irq_desc wasn't set in legacy EQ's
[deliverable/linux.git] / drivers / net / ppp / ppp_generic.c
CommitLineData
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
1da177e4
LT		 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>
7a95d267 30#include <linux/idr.h>
1da177e4
LT		 31#include <linux/netdevice.h>
32#include <linux/poll.h>
33#include <linux/ppp_defs.h>
34#include <linux/filter.h>
bf7daebb 35#include <linux/ppp-ioctl.h>
1da177e4
LT		 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>
1da177e4
LT		 44#include <linux/rwsem.h>
45#include <linux/stddef.h>
46#include <linux/device.h>
8ed965d6 47#include <linux/mutex.h>
5a0e3ad6 48#include <linux/slab.h>
96545aeb 49#include <asm/unaligned.h>
1da177e4 50#include <net/slhc_vj.h>
60063497 51#include <linux/atomic.h>
1da177e4 52
273ec51d
CG		 53#include <linux/nsproxy.h>
54#include <net/net_namespace.h>
55#include <net/netns/generic.h>
56
1da177e4
LT		 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 */
1da177e4
LT		 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 */
78struct 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
b385a144 91#define PF_TO_X(pf, X) container_of(pf, X, file)
1da177e4
LT		 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
e51f6ff3
KG		 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 */
101struct ppp_link_stats {
102 u64 rx_packets;
103 u64 tx_packets;
104 u64 rx_bytes;
105 u64 tx_bytes;
106};
107
1da177e4
LT		 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 */
114struct 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 */
739840d5 136 int closing; /* is device closing down? a8 */
1da177e4
LT		 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 */
1da177e4 145#ifdef CONFIG_PPP_FILTER
568f194e
DB		 146 struct sk_filter *pass_filter; /* filter for packets to pass */
147 struct sk_filter *active_filter;/* filter for pkts to reset idle */
1da177e4 148#endif /* CONFIG_PPP_FILTER */
273ec51d 149 struct net *ppp_net; /* the net we belong to */
e51f6ff3 150 struct ppp_link_stats stats64; /* 64 bit network stats */
1da177e4
LT		 151};
152
153/*
154 * Bits in flags: SC_NO_TCP_CCID, SC_CCP_OPEN, SC_CCP_UP, SC_LOOP_TRAFFIC,
b3f9b92a
MD		 155 * SC_MULTILINK, SC_MP_SHORTSEQ, SC_MP_XSHORTSEQ, SC_COMP_TCP, SC_REJ_COMP_TCP,
156 * SC_MUST_COMP
1da177e4
LT		 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 \
b3f9b92a 162 |SC_COMP_TCP|SC_REJ_COMP_TCP|SC_MUST_COMP)
1da177e4
LT		 163
164/*
165 * Private data structure for each channel.
166 * This includes the data structure used for multilink.
167 */
168struct 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 */
273ec51d 175 struct net *chan_net; /* the net channel belongs to */
1da177e4
LT		 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 */
fa44a73c 182 int speed; /* speed of the corresponding ppp channel*/
1da177e4
LT		 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
15fd0cd9 195static DEFINE_MUTEX(ppp_mutex);
1da177e4 196static atomic_t ppp_unit_count = ATOMIC_INIT(0);
1da177e4
LT		 197static atomic_t channel_count = ATOMIC_INIT(0);
198
273ec51d 199/* per-net private data for this module */
f99189b1 200static int ppp_net_id __read_mostly;
273ec51d
CG		 201struct 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
1da177e4 225/* Get the PPP protocol number from a skb */
96545aeb 226#define PPP_PROTO(skb) get_unaligned_be16((skb)->data)
1da177e4
LT		 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. */
273ec51d
CG		 248static int ppp_unattached_ioctl(struct net *net, struct ppp_file *pf,
249 struct file *file, unsigned int cmd, unsigned long arg);
9a5d2bd9 250static void ppp_xmit_process(struct ppp *ppp);
1da177e4
LT		 251static void ppp_send_frame(struct ppp *ppp, struct sk_buff *skb);
252static void ppp_push(struct ppp *ppp);
253static void ppp_channel_push(struct channel *pch);
254static void ppp_receive_frame(struct ppp *ppp, struct sk_buff *skb,
255 struct channel *pch);
256static void ppp_receive_error(struct ppp *ppp);
257static void ppp_receive_nonmp_frame(struct ppp *ppp, struct sk_buff *skb);
258static struct sk_buff *ppp_decompress_frame(struct ppp *ppp,
259 struct sk_buff *skb);
260#ifdef CONFIG_PPP_MULTILINK
261static void ppp_receive_mp_frame(struct ppp *ppp, struct sk_buff *skb,
262 struct channel *pch);
263static void ppp_mp_insert(struct ppp *ppp, struct sk_buff *skb);
264static struct sk_buff *ppp_mp_reconstruct(struct ppp *ppp);
265static int ppp_mp_explode(struct ppp *ppp, struct sk_buff *skb);
266#endif /* CONFIG_PPP_MULTILINK */
267static int ppp_set_compress(struct ppp *ppp, unsigned long arg);
268static void ppp_ccp_peek(struct ppp *ppp, struct sk_buff *skb, int inbound);
269static void ppp_ccp_closed(struct ppp *ppp);
270static struct compressor *find_compressor(int type);
271static void ppp_get_stats(struct ppp *ppp, struct ppp_stats *st);
273ec51d 272static struct ppp *ppp_create_interface(struct net *net, int unit, int *retp);
1da177e4
LT		 273static void init_ppp_file(struct ppp_file *pf, int kind);
274static void ppp_shutdown_interface(struct ppp *ppp);
275static void ppp_destroy_interface(struct ppp *ppp);
273ec51d
CG		 276static struct ppp *ppp_find_unit(struct ppp_net *pn, int unit);
277static struct channel *ppp_find_channel(struct ppp_net *pn, int unit);
1da177e4
LT		 278static int ppp_connect_channel(struct channel *pch, int unit);
279static int ppp_disconnect_channel(struct channel *pch);
280static void ppp_destroy_channel(struct channel *pch);
7a95d267 281static int unit_get(struct idr *p, void *ptr);
85997576 282static int unit_set(struct idr *p, void *ptr, int n);
7a95d267
CG		 283static void unit_put(struct idr *p, int n);
284static void *unit_find(struct idr *p, int n);
1da177e4 285
56b22935 286static struct class *ppp_class;
1da177e4 287
273ec51d
CG		 288/* per net-namespace data */
289static 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
1da177e4
LT		 296/* Translates a PPP protocol number to a NP index (NP == network protocol) */
297static 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 */
317static 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};
6aa20a22 325
1da177e4
LT		 326/* Translates an ethertype into an NP index */
327static 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 */
348static 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 */
376static 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
f3ff8a4d 386static int ppp_release(struct inode *unused, struct file *file)
1da177e4
LT		 387{
388 struct ppp_file *pf = file->private_data;
389 struct ppp *ppp;
390
cd228d54 391 if (pf) {
1da177e4
LT		 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
412static 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;
19937d04 419 struct iovec iov;
1da177e4
LT		 420
421 ret = count;
422
cd228d54 423 if (!pf)
1da177e4
LT		 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);
8e95a202
JP		 441 if (ppp->n_channels == 0 &&
442 (ppp->flags & SC_LOOP_TRAFFIC) == 0)
1da177e4
LT		 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
cd228d54 456 if (!skb)
1da177e4
LT		 457 goto out;
458
459 ret = -EOVERFLOW;
460 if (skb->len > count)
461 goto outf;
462 ret = -EFAULT;
19937d04
SA		 463 iov.iov_base = buf;
464 iov.iov_len = count;
465 if (skb_copy_datagram_iovec(skb, 0, &iov, skb->len))
1da177e4
LT		 466 goto outf;
467 ret = skb->len;
468
469 outf:
470 kfree_skb(skb);
471 out:
472 return ret;
473}
474
475static 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
cd228d54 482 if (!pf)
1da177e4
LT		 483 return -ENXIO;
484 ret = -ENOMEM;
485 skb = alloc_skb(count + pf->hdrlen, GFP_KERNEL);
cd228d54 486 if (!skb)
1da177e4
LT		 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 */
513static unsigned int ppp_poll(struct file *file, poll_table *wait)
514{
515 struct ppp_file *pf = file->private_data;
516 unsigned int mask;
517
cd228d54 518 if (!pf)
1da177e4
LT		 519 return 0;
520 poll_wait(file, &pf->rwait, wait);
521 mask = POLLOUT | POLLWRNORM;
cd228d54 522 if (skb_peek(&pf->rq))
1da177e4
LT		 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);
8e95a202
JP		 529 if (ppp->n_channels == 0 &&
530 (ppp->flags & SC_LOOP_TRAFFIC) == 0)
1da177e4
LT		 531 mask |= POLLIN | POLLRDNORM;
532 }
533
534 return mask;
535}
536
537#ifdef CONFIG_PPP_FILTER
538static int get_filter(void __user *arg, struct sock_filter **p)
539{
540 struct sock_fprog uprog;
541 struct sock_filter *code = NULL;
3916a319 542 int len;
1da177e4
LT		 543
544 if (copy_from_user(&uprog, arg, sizeof(uprog)))
545 return -EFAULT;
546
1da177e4
LT		 547 if (!uprog.len) {
548 *p = NULL;
549 return 0;
550 }
551
552 len = uprog.len * sizeof(struct sock_filter);
b23d00e9
JL		 553 code = memdup_user(uprog.filter, len);
554 if (IS_ERR(code))
555 return PTR_ERR(code);
1da177e4 556
1da177e4
LT		 557 *p = code;
558 return uprog.len;
559}
560#endif /* CONFIG_PPP_FILTER */
561
f3ff8a4d 562static long ppp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1da177e4
LT		 563{
564 struct ppp_file *pf = file->private_data;
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
cd228d54 574 if (!pf)
273ec51d
CG		 575 return ppp_unattached_ioctl(current->nsproxy->net_ns,
576 pf, file, cmd, arg);
1da177e4
LT		 577
578 if (cmd == PPPIOCDETACH) {
579 /*
580 * We have to be careful here... if the file descriptor
581 * has been dup'd, we could have another process in the
582 * middle of a poll using the same file *, so we had
583 * better not free the interface data structures -
584 * instead we fail the ioctl. Even in this case, we
585 * shut down the interface if we are the owner of it.
586 * Actually, we should get rid of PPPIOCDETACH, userland
587 * (i.e. pppd) could achieve the same effect by closing
588 * this fd and reopening /dev/ppp.
589 */
590 err = -EINVAL;
15fd0cd9 591 mutex_lock(&ppp_mutex);
1da177e4
LT		 592 if (pf->kind == INTERFACE) {
593 ppp = PF_TO_PPP(pf);
594 if (file == ppp->owner)
595 ppp_shutdown_interface(ppp);
596 }
516e0cc5 597 if (atomic_long_read(&file->f_count) <= 2) {
f3ff8a4d 598 ppp_release(NULL, file);
1da177e4
LT		 599 err = 0;
600 } else
b48f8c23
DM		 601 pr_warn("PPPIOCDETACH file->f_count=%ld\n",
602 atomic_long_read(&file->f_count));
15fd0cd9 603 mutex_unlock(&ppp_mutex);
1da177e4
LT		 604 return err;
605 }
606
607 if (pf->kind == CHANNEL) {
f3ff8a4d 608 struct channel *pch;
1da177e4
LT		 609 struct ppp_channel *chan;
610
15fd0cd9 611 mutex_lock(&ppp_mutex);
f3ff8a4d
AC		 612 pch = PF_TO_CHANNEL(pf);
613
1da177e4
LT		 614 switch (cmd) {
615 case PPPIOCCONNECT:
616 if (get_user(unit, p))
617 break;
618 err = ppp_connect_channel(pch, unit);
619 break;
620
621 case PPPIOCDISCONN:
622 err = ppp_disconnect_channel(pch);
623 break;
624
625 default:
626 down_read(&pch->chan_sem);
627 chan = pch->chan;
628 err = -ENOTTY;
629 if (chan && chan->ops->ioctl)
630 err = chan->ops->ioctl(chan, cmd, arg);
631 up_read(&pch->chan_sem);
632 }
15fd0cd9 633 mutex_unlock(&ppp_mutex);
1da177e4
LT		 634 return err;
635 }
636
637 if (pf->kind != INTERFACE) {
638 /* can't happen */
b48f8c23 639 pr_err("PPP: not interface or channel??\n");
1da177e4
LT		 640 return -EINVAL;
641 }
642
15fd0cd9 643 mutex_lock(&ppp_mutex);
1da177e4
LT		 644 ppp = PF_TO_PPP(pf);
645 switch (cmd) {
646 case PPPIOCSMRU:
647 if (get_user(val, p))
648 break;
649 ppp->mru = val;
650 err = 0;
651 break;
652
653 case PPPIOCSFLAGS:
654 if (get_user(val, p))
655 break;
656 ppp_lock(ppp);
657 cflags = ppp->flags & ~val;
658 ppp->flags = val & SC_FLAG_BITS;
659 ppp_unlock(ppp);
660 if (cflags & SC_CCP_OPEN)
661 ppp_ccp_closed(ppp);
662 err = 0;
663 break;
664
665 case PPPIOCGFLAGS:
666 val = ppp->flags | ppp->xstate | ppp->rstate;
667 if (put_user(val, p))
668 break;
669 err = 0;
670 break;
671
672 case PPPIOCSCOMPRESS:
673 err = ppp_set_compress(ppp, arg);
674 break;
675
676 case PPPIOCGUNIT:
677 if (put_user(ppp->file.index, p))
678 break;
679 err = 0;
680 break;
681
682 case PPPIOCSDEBUG:
683 if (get_user(val, p))
684 break;
685 ppp->debug = val;
686 err = 0;
687 break;
688
689 case PPPIOCGDEBUG:
690 if (put_user(ppp->debug, p))
691 break;
692 err = 0;
693 break;
694
695 case PPPIOCGIDLE:
696 idle.xmit_idle = (jiffies - ppp->last_xmit) / HZ;
697 idle.recv_idle = (jiffies - ppp->last_recv) / HZ;
698 if (copy_to_user(argp, &idle, sizeof(idle)))
699 break;
700 err = 0;
701 break;
702
703 case PPPIOCSMAXCID:
704 if (get_user(val, p))
705 break;
706 val2 = 15;
707 if ((val >> 16) != 0) {
708 val2 = val >> 16;
709 val &= 0xffff;
710 }
711 vj = slhc_init(val2+1, val+1);
cd228d54 712 if (!vj) {
b48f8c23
DM		 713 netdev_err(ppp->dev,
714 "PPP: no memory (VJ compressor)\n");
1da177e4
LT		 715 err = -ENOMEM;
716 break;
717 }
718 ppp_lock(ppp);
cd228d54 719 if (ppp->vj)
1da177e4
LT		 720 slhc_free(ppp->vj);
721 ppp->vj = vj;
722 ppp_unlock(ppp);
723 err = 0;
724 break;
725
726 case PPPIOCGNPMODE:
727 case PPPIOCSNPMODE:
728 if (copy_from_user(&npi, argp, sizeof(npi)))
729 break;
730 err = proto_to_npindex(npi.protocol);
731 if (err < 0)
732 break;
733 i = err;
734 if (cmd == PPPIOCGNPMODE) {
735 err = -EFAULT;
736 npi.mode = ppp->npmode[i];
737 if (copy_to_user(argp, &npi, sizeof(npi)))
738 break;
739 } else {
740 ppp->npmode[i] = npi.mode;
741 /* we may be able to transmit more packets now (??) */
742 netif_wake_queue(ppp->dev);
743 }
744 err = 0;
745 break;
746
747#ifdef CONFIG_PPP_FILTER
748 case PPPIOCSPASS:
749 {
750 struct sock_filter *code;
568f194e 751
1da177e4
LT		 752 err = get_filter(argp, &code);
753 if (err >= 0) {
b1fcd35c 754 struct sock_fprog_kern fprog = {
568f194e
DB		 755 .len = err,
756 .filter = code,
757 };
758
1da177e4 759 ppp_lock(ppp);
568f194e
DB		 760 if (ppp->pass_filter)
761 sk_unattached_filter_destroy(ppp->pass_filter);
762 err = sk_unattached_filter_create(&ppp->pass_filter,
763 &fprog);
764 kfree(code);
1da177e4 765 ppp_unlock(ppp);
1da177e4
LT		 766 }
767 break;
768 }
769 case PPPIOCSACTIVE:
770 {
771 struct sock_filter *code;
568f194e 772
1da177e4
LT		 773 err = get_filter(argp, &code);
774 if (err >= 0) {
b1fcd35c 775 struct sock_fprog_kern fprog = {
568f194e
DB		 776 .len = err,
777 .filter = code,
778 };
779
1da177e4 780 ppp_lock(ppp);
568f194e
DB		 781 if (ppp->active_filter)
782 sk_unattached_filter_destroy(ppp->active_filter);
783 err = sk_unattached_filter_create(&ppp->active_filter,
784 &fprog);
785 kfree(code);
1da177e4 786 ppp_unlock(ppp);
1da177e4
LT		 787 }
788 break;
789 }
790#endif /* CONFIG_PPP_FILTER */
791
792#ifdef CONFIG_PPP_MULTILINK
793 case PPPIOCSMRRU:
794 if (get_user(val, p))
795 break;
796 ppp_recv_lock(ppp);
797 ppp->mrru = val;
798 ppp_recv_unlock(ppp);
799 err = 0;
800 break;
801#endif /* CONFIG_PPP_MULTILINK */
802
803 default:
804 err = -ENOTTY;
805 }
15fd0cd9 806 mutex_unlock(&ppp_mutex);
1da177e4
LT		 807 return err;
808}
809
273ec51d
CG		 810static int ppp_unattached_ioctl(struct net *net, struct ppp_file *pf,
811 struct file *file, unsigned int cmd, unsigned long arg)
1da177e4
LT		 812{
813 int unit, err = -EFAULT;
814 struct ppp *ppp;
815 struct channel *chan;
273ec51d 816 struct ppp_net *pn;
1da177e4
LT		 817 int __user *p = (int __user *)arg;
818
15fd0cd9 819 mutex_lock(&ppp_mutex);
1da177e4
LT		 820 switch (cmd) {
821 case PPPIOCNEWUNIT:
822 /* Create a new ppp unit */
823 if (get_user(unit, p))
824 break;
273ec51d 825 ppp = ppp_create_interface(net, unit, &err);
cd228d54 826 if (!ppp)
1da177e4
LT		 827 break;
828 file->private_data = &ppp->file;
829 ppp->owner = file;
830 err = -EFAULT;
831 if (put_user(ppp->file.index, p))
832 break;
833 err = 0;
834 break;
835
836 case PPPIOCATTACH:
837 /* Attach to an existing ppp unit */
838 if (get_user(unit, p))
839 break;
1da177e4 840 err = -ENXIO;
273ec51d
CG		 841 pn = ppp_pernet(net);
842 mutex_lock(&pn->all_ppp_mutex);
843 ppp = ppp_find_unit(pn, unit);
cd228d54 844 if (ppp) {
1da177e4
LT		 845 atomic_inc(&ppp->file.refcnt);
846 file->private_data = &ppp->file;
847 err = 0;
848 }
273ec51d 849 mutex_unlock(&pn->all_ppp_mutex);
1da177e4
LT		 850 break;
851
852 case PPPIOCATTCHAN:
853 if (get_user(unit, p))
854 break;
1da177e4 855 err = -ENXIO;
273ec51d
CG		 856 pn = ppp_pernet(net);
857 spin_lock_bh(&pn->all_channels_lock);
858 chan = ppp_find_channel(pn, unit);
cd228d54 859 if (chan) {
1da177e4
LT		 860 atomic_inc(&chan->file.refcnt);
861 file->private_data = &chan->file;
862 err = 0;
863 }
273ec51d 864 spin_unlock_bh(&pn->all_channels_lock);
1da177e4
LT		 865 break;
866
867 default:
868 err = -ENOTTY;
869 }
15fd0cd9 870 mutex_unlock(&ppp_mutex);
1da177e4
LT		 871 return err;
872}
873
d54b1fdb 874static const struct file_operations ppp_device_fops = {
1da177e4
LT		 875 .owner = THIS_MODULE,
876 .read = ppp_read,
877 .write = ppp_write,
878 .poll = ppp_poll,
f3ff8a4d 879 .unlocked_ioctl = ppp_ioctl,
1da177e4 880 .open = ppp_open,
6038f373
AB		 881 .release = ppp_release,
882 .llseek = noop_llseek,
1da177e4
LT		 883};
884
273ec51d
CG		 885static __net_init int ppp_init_net(struct net *net)
886{
741a6fa2 887 struct ppp_net *pn = net_generic(net, ppp_net_id);
273ec51d
CG		 888
889 idr_init(&pn->units_idr);
890 mutex_init(&pn->all_ppp_mutex);
891
892 INIT_LIST_HEAD(&pn->all_channels);
893 INIT_LIST_HEAD(&pn->new_channels);
894
895 spin_lock_init(&pn->all_channels_lock);
896
273ec51d
CG		 897 return 0;
898}
899
900static __net_exit void ppp_exit_net(struct net *net)
901{
741a6fa2 902 struct ppp_net *pn = net_generic(net, ppp_net_id);
273ec51d 903
273ec51d 904 idr_destroy(&pn->units_idr);
273ec51d
CG		 905}
906
0012985d 907static struct pernet_operations ppp_net_ops = {
273ec51d
CG		 908 .init = ppp_init_net,
909 .exit = ppp_exit_net,
741a6fa2
EB		 910 .id = &ppp_net_id,
911 .size = sizeof(struct ppp_net),
273ec51d
CG		 912};
913
1da177e4
LT		 914#define PPP_MAJOR 108
915
916/* Called at boot time if ppp is compiled into the kernel,
917 or at module load time (from init_module) if compiled as a module. */
918static int __init ppp_init(void)
919{
920 int err;
921
b48f8c23 922 pr_info("PPP generic driver version " PPP_VERSION "\n");
273ec51d 923
741a6fa2 924 err = register_pernet_device(&ppp_net_ops);
273ec51d 925 if (err) {
b48f8c23 926 pr_err("failed to register PPP pernet device (%d)\n", err);
273ec51d 927 goto out;
1da177e4
LT		 928 }
929
273ec51d
CG		 930 err = register_chrdev(PPP_MAJOR, "ppp", &ppp_device_fops);
931 if (err) {
b48f8c23 932 pr_err("failed to register PPP device (%d)\n", err);
273ec51d
CG		 933 goto out_net;
934 }
935
936 ppp_class = class_create(THIS_MODULE, "ppp");
937 if (IS_ERR(ppp_class)) {
938 err = PTR_ERR(ppp_class);
939 goto out_chrdev;
940 }
941
942 /* not a big deal if we fail here :-) */
943 device_create(ppp_class, NULL, MKDEV(PPP_MAJOR, 0), NULL, "ppp");
944
945 return 0;
1da177e4 946
1da177e4
LT		 947out_chrdev:
948 unregister_chrdev(PPP_MAJOR, "ppp");
273ec51d 949out_net:
741a6fa2 950 unregister_pernet_device(&ppp_net_ops);
273ec51d
CG		 951out:
952 return err;
1da177e4
LT		 953}
954
955/*
956 * Network interface unit routines.
957 */
424efe9c 958static netdev_tx_t
1da177e4
LT		 959ppp_start_xmit(struct sk_buff *skb, struct net_device *dev)
960{
c8019bf3 961 struct ppp *ppp = netdev_priv(dev);
1da177e4
LT		 962 int npi, proto;
963 unsigned char *pp;
964
965 npi = ethertype_to_npindex(ntohs(skb->protocol));
966 if (npi < 0)
967 goto outf;
968
969 /* Drop, accept or reject the packet */
970 switch (ppp->npmode[npi]) {
971 case NPMODE_PASS:
972 break;
973 case NPMODE_QUEUE:
974 /* it would be nice to have a way to tell the network
975 system to queue this one up for later. */
976 goto outf;
977 case NPMODE_DROP:
978 case NPMODE_ERROR:
979 goto outf;
980 }
981
982 /* Put the 2-byte PPP protocol number on the front,
983 making sure there is room for the address and control fields. */
7b797d5b
HX		 984 if (skb_cow_head(skb, PPP_HDRLEN))
985 goto outf;
986
1da177e4
LT		 987 pp = skb_push(skb, 2);
988 proto = npindex_to_proto[npi];
96545aeb 989 put_unaligned_be16(proto, pp);
1da177e4 990
1da177e4 991 skb_queue_tail(&ppp->file.xq, skb);
9a5d2bd9 992 ppp_xmit_process(ppp);
6ed10654 993 return NETDEV_TX_OK;
1da177e4
LT		 994
995 outf:
996 kfree_skb(skb);
6ceffd47 997 ++dev->stats.tx_dropped;
6ed10654 998 return NETDEV_TX_OK;
1da177e4
LT		 999}
1000
1da177e4
LT		 1001static int
1002ppp_net_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
1003{
c8019bf3 1004 struct ppp *ppp = netdev_priv(dev);
1da177e4
LT		 1005 int err = -EFAULT;
1006 void __user *addr = (void __user *) ifr->ifr_ifru.ifru_data;
1007 struct ppp_stats stats;
1008 struct ppp_comp_stats cstats;
1009 char *vers;
1010
1011 switch (cmd) {
1012 case SIOCGPPPSTATS:
1013 ppp_get_stats(ppp, &stats);
1014 if (copy_to_user(addr, &stats, sizeof(stats)))
1015 break;
1016 err = 0;
1017 break;
1018
1019 case SIOCGPPPCSTATS:
1020 memset(&cstats, 0, sizeof(cstats));
cd228d54 1021 if (ppp->xc_state)
1da177e4 1022 ppp->xcomp->comp_stat(ppp->xc_state, &cstats.c);
cd228d54 1023 if (ppp->rc_state)
1da177e4
LT		 1024 ppp->rcomp->decomp_stat(ppp->rc_state, &cstats.d);
1025 if (copy_to_user(addr, &cstats, sizeof(cstats)))
1026 break;
1027 err = 0;
1028 break;
1029
1030 case SIOCGPPPVER:
1031 vers = PPP_VERSION;
1032 if (copy_to_user(addr, vers, strlen(vers) + 1))
1033 break;
1034 err = 0;
1035 break;
1036
1037 default:
1038 err = -EINVAL;
1039 }
1040
1041 return err;
1042}
1043
b77bc206 1044static struct rtnl_link_stats64*
e51f6ff3
KG		 1045ppp_get_stats64(struct net_device *dev, struct rtnl_link_stats64 *stats64)
1046{
1047 struct ppp *ppp = netdev_priv(dev);
1048
1049 ppp_recv_lock(ppp);
1050 stats64->rx_packets = ppp->stats64.rx_packets;
1051 stats64->rx_bytes = ppp->stats64.rx_bytes;
1052 ppp_recv_unlock(ppp);
1053
1054 ppp_xmit_lock(ppp);
1055 stats64->tx_packets = ppp->stats64.tx_packets;
1056 stats64->tx_bytes = ppp->stats64.tx_bytes;
1057 ppp_xmit_unlock(ppp);
1058
1059 stats64->rx_errors = dev->stats.rx_errors;
1060 stats64->tx_errors = dev->stats.tx_errors;
1061 stats64->rx_dropped = dev->stats.rx_dropped;
1062 stats64->tx_dropped = dev->stats.tx_dropped;
1063 stats64->rx_length_errors = dev->stats.rx_length_errors;
1064
1065 return stats64;
1066}
1067
303c07db
ED		 1068static struct lock_class_key ppp_tx_busylock;
1069static int ppp_dev_init(struct net_device *dev)
1070{
1071 dev->qdisc_tx_busylock = &ppp_tx_busylock;
1072 return 0;
1073}
1074
52256cfc 1075static const struct net_device_ops ppp_netdev_ops = {
303c07db 1076 .ndo_init = ppp_dev_init,
e51f6ff3
KG		 1077 .ndo_start_xmit = ppp_start_xmit,
1078 .ndo_do_ioctl = ppp_net_ioctl,
1079 .ndo_get_stats64 = ppp_get_stats64,
52256cfc
SH		 1080};
1081
1da177e4
LT		 1082static void ppp_setup(struct net_device *dev)
1083{
52256cfc 1084 dev->netdev_ops = &ppp_netdev_ops;
1da177e4 1085 dev->hard_header_len = PPP_HDRLEN;
bf7daebb 1086 dev->mtu = PPP_MRU;
1da177e4
LT		 1087 dev->addr_len = 0;
1088 dev->tx_queue_len = 3;
1089 dev->type = ARPHRD_PPP;
1090 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
273ec51d 1091 dev->features |= NETIF_F_NETNS_LOCAL;
8b2d850d 1092 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
1da177e4
LT		 1093}
1094
1095/*
1096 * Transmit-side routines.
1097 */
1098
1099/*
1100 * Called to do any work queued up on the transmit side
1101 * that can now be done.
1102 */
9a5d2bd9 1103static void
1da177e4
LT		 1104ppp_xmit_process(struct ppp *ppp)
1105{
1106 struct sk_buff *skb;
1107
1108 ppp_xmit_lock(ppp);
739840d5 1109 if (!ppp->closing) {
1da177e4 1110 ppp_push(ppp);
8e95a202
JP		 1111 while (!ppp->xmit_pending &&
1112 (skb = skb_dequeue(&ppp->file.xq)))
1da177e4
LT		 1113 ppp_send_frame(ppp, skb);
1114 /* If there's no work left to do, tell the core net
1115 code that we can accept some more. */
9a5d2bd9 1116 if (!ppp->xmit_pending && !skb_peek(&ppp->file.xq))
1da177e4 1117 netif_wake_queue(ppp->dev);
9a5d2bd9
DW		 1118 else
1119 netif_stop_queue(ppp->dev);
1da177e4
LT		 1120 }
1121 ppp_xmit_unlock(ppp);
1122}
1123
b3f9b92a
MD		 1124static inline struct sk_buff *
1125pad_compress_skb(struct ppp *ppp, struct sk_buff *skb)
1126{
1127 struct sk_buff *new_skb;
1128 int len;
1129 int new_skb_size = ppp->dev->mtu +
1130 ppp->xcomp->comp_extra + ppp->dev->hard_header_len;
1131 int compressor_skb_size = ppp->dev->mtu +
1132 ppp->xcomp->comp_extra + PPP_HDRLEN;
1133 new_skb = alloc_skb(new_skb_size, GFP_ATOMIC);
1134 if (!new_skb) {
1135 if (net_ratelimit())
b48f8c23 1136 netdev_err(ppp->dev, "PPP: no memory (comp pkt)\n");
b3f9b92a
MD		 1137 return NULL;
1138 }
1139 if (ppp->dev->hard_header_len > PPP_HDRLEN)
1140 skb_reserve(new_skb,
1141 ppp->dev->hard_header_len - PPP_HDRLEN);
1142
1143 /* compressor still expects A/C bytes in hdr */
1144 len = ppp->xcomp->compress(ppp->xc_state, skb->data - 2,
1145 new_skb->data, skb->len + 2,
1146 compressor_skb_size);
1147 if (len > 0 && (ppp->flags & SC_CCP_UP)) {
968d7018 1148 consume_skb(skb);
b3f9b92a
MD		 1149 skb = new_skb;
1150 skb_put(skb, len);
1151 skb_pull(skb, 2); /* pull off A/C bytes */
1152 } else if (len == 0) {
1153 /* didn't compress, or CCP not up yet */
968d7018 1154 consume_skb(new_skb);
b3f9b92a
MD		 1155 new_skb = skb;
1156 } else {
1157 /*
1158 * (len < 0)
1159 * MPPE requires that we do not send unencrypted
1160 * frames. The compressor will return -1 if we
1161 * should drop the frame. We cannot simply test
1162 * the compress_proto because MPPE and MPPC share
1163 * the same number.
1164 */
1165 if (net_ratelimit())
b48f8c23 1166 netdev_err(ppp->dev, "ppp: compressor dropped pkt\n");
b3f9b92a 1167 kfree_skb(skb);
968d7018 1168 consume_skb(new_skb);
b3f9b92a
MD		 1169 new_skb = NULL;
1170 }
1171 return new_skb;
1172}
1173
1da177e4
LT		 1174/*
1175 * Compress and send a frame.
1176 * The caller should have locked the xmit path,
1177 * and xmit_pending should be 0.
1178 */
1179static void
1180ppp_send_frame(struct ppp *ppp, struct sk_buff *skb)
1181{
1182 int proto = PPP_PROTO(skb);
1183 struct sk_buff *new_skb;
1184 int len;
1185 unsigned char *cp;
1186
1187 if (proto < 0x8000) {
1188#ifdef CONFIG_PPP_FILTER
1189 /* check if we should pass this packet */
1190 /* the filter instructions are constructed assuming
1191 a four-byte PPP header on each packet */
1192 *skb_push(skb, 2) = 1;
8e95a202 1193 if (ppp->pass_filter &&
568f194e 1194 SK_RUN_FILTER(ppp->pass_filter, skb) == 0) {
1da177e4 1195 if (ppp->debug & 1)
b48f8c23
DM		 1196 netdev_printk(KERN_DEBUG, ppp->dev,
1197 "PPP: outbound frame "
1198 "not passed\n");
1da177e4
LT		 1199 kfree_skb(skb);
1200 return;
1201 }
1202 /* if this packet passes the active filter, record the time */
8e95a202 1203 if (!(ppp->active_filter &&
568f194e 1204 SK_RUN_FILTER(ppp->active_filter, skb) == 0))
1da177e4
LT		 1205 ppp->last_xmit = jiffies;
1206 skb_pull(skb, 2);
1207#else
1208 /* for data packets, record the time */
1209 ppp->last_xmit = jiffies;
1210#endif /* CONFIG_PPP_FILTER */
1211 }
1212
e51f6ff3
KG		 1213 ++ppp->stats64.tx_packets;
1214 ppp->stats64.tx_bytes += skb->len - 2;
1da177e4
LT		 1215
1216 switch (proto) {
1217 case PPP_IP:
cd228d54 1218 if (!ppp->vj || (ppp->flags & SC_COMP_TCP) == 0)
1da177e4
LT		 1219 break;
1220 /* try to do VJ TCP header compression */
1221 new_skb = alloc_skb(skb->len + ppp->dev->hard_header_len - 2,
1222 GFP_ATOMIC);
cd228d54 1223 if (!new_skb) {
b48f8c23 1224 netdev_err(ppp->dev, "PPP: no memory (VJ comp pkt)\n");
1da177e4
LT		 1225 goto drop;
1226 }
1227 skb_reserve(new_skb, ppp->dev->hard_header_len - 2);
1228 cp = skb->data + 2;
1229 len = slhc_compress(ppp->vj, cp, skb->len - 2,
1230 new_skb->data + 2, &cp,
1231 !(ppp->flags & SC_NO_TCP_CCID));
1232 if (cp == skb->data + 2) {
1233 /* didn't compress */
968d7018 1234 consume_skb(new_skb);
1da177e4
LT		 1235 } else {
1236 if (cp[0] & SL_TYPE_COMPRESSED_TCP) {
1237 proto = PPP_VJC_COMP;
1238 cp[0] &= ~SL_TYPE_COMPRESSED_TCP;
1239 } else {
1240 proto = PPP_VJC_UNCOMP;
1241 cp[0] = skb->data[2];
1242 }
968d7018 1243 consume_skb(skb);
1da177e4
LT		 1244 skb = new_skb;
1245 cp = skb_put(skb, len + 2);
1246 cp[0] = 0;
1247 cp[1] = proto;
1248 }
1249 break;
1250
1251 case PPP_CCP:
1252 /* peek at outbound CCP frames */
1253 ppp_ccp_peek(ppp, skb, 0);
1254 break;
1255 }
1256
1257 /* try to do packet compression */
8e95a202
JP		 1258 if ((ppp->xstate & SC_COMP_RUN) && ppp->xc_state &&
1259 proto != PPP_LCP && proto != PPP_CCP) {
b3f9b92a
MD		 1260 if (!(ppp->flags & SC_CCP_UP) && (ppp->flags & SC_MUST_COMP)) {
1261 if (net_ratelimit())
b48f8c23
DM		 1262 netdev_err(ppp->dev,
1263 "ppp: compression required but "
1264 "down - pkt dropped.\n");
1da177e4
LT		 1265 goto drop;
1266 }
b3f9b92a
MD		 1267 skb = pad_compress_skb(ppp, skb);
1268 if (!skb)
1269 goto drop;
1da177e4
LT		 1270 }
1271
1272 /*
1273 * If we are waiting for traffic (demand dialling),
1274 * queue it up for pppd to receive.
1275 */
1276 if (ppp->flags & SC_LOOP_TRAFFIC) {
1277 if (ppp->file.rq.qlen > PPP_MAX_RQLEN)
1278 goto drop;
1279 skb_queue_tail(&ppp->file.rq, skb);
1280 wake_up_interruptible(&ppp->file.rwait);
1281 return;
1282 }
1283
1284 ppp->xmit_pending = skb;
1285 ppp_push(ppp);
1286 return;
1287
1288 drop:
1d2f8c95 1289 kfree_skb(skb);
8c0469cd 1290 ++ppp->dev->stats.tx_errors;
1da177e4
LT		 1291}
1292
1293/*
1294 * Try to send the frame in xmit_pending.
1295 * The caller should have the xmit path locked.
1296 */
1297static void
1298ppp_push(struct ppp *ppp)
1299{
1300 struct list_head *list;
1301 struct channel *pch;
1302 struct sk_buff *skb = ppp->xmit_pending;
1303
cd228d54 1304 if (!skb)
1da177e4
LT		 1305 return;
1306
1307 list = &ppp->channels;
1308 if (list_empty(list)) {
1309 /* nowhere to send the packet, just drop it */
1310 ppp->xmit_pending = NULL;
1311 kfree_skb(skb);
1312 return;
1313 }
1314
1315 if ((ppp->flags & SC_MULTILINK) == 0) {
1316 /* not doing multilink: send it down the first channel */
1317 list = list->next;
1318 pch = list_entry(list, struct channel, clist);
1319
1320 spin_lock_bh(&pch->downl);
1321 if (pch->chan) {
1322 if (pch->chan->ops->start_xmit(pch->chan, skb))
1323 ppp->xmit_pending = NULL;
1324 } else {
1325 /* channel got unregistered */
1326 kfree_skb(skb);
1327 ppp->xmit_pending = NULL;
1328 }
1329 spin_unlock_bh(&pch->downl);
1330 return;
1331 }
1332
1333#ifdef CONFIG_PPP_MULTILINK
1334 /* Multilink: fragment the packet over as many links
1335 as can take the packet at the moment. */
1336 if (!ppp_mp_explode(ppp, skb))
1337 return;
1338#endif /* CONFIG_PPP_MULTILINK */
1339
1340 ppp->xmit_pending = NULL;
1341 kfree_skb(skb);
1342}
1343
1344#ifdef CONFIG_PPP_MULTILINK
d39cd5e9 1345static bool mp_protocol_compress __read_mostly = true;
1346module_param(mp_protocol_compress, bool, S_IRUGO | S_IWUSR);
1347MODULE_PARM_DESC(mp_protocol_compress,
1348 "compress protocol id in multilink fragments");
1349
1da177e4
LT		 1350/*
1351 * Divide a packet to be transmitted into fragments and
1352 * send them out the individual links.
1353 */
1354static int ppp_mp_explode(struct ppp *ppp, struct sk_buff *skb)
1355{
fa44a73c
LS		 1356 int len, totlen;
1357 int i, bits, hdrlen, mtu;
1358 int flen;
1359 int navail, nfree, nzero;
1360 int nbigger;
1361 int totspeed;
1362 int totfree;
1da177e4
LT		 1363 unsigned char *p, *q;
1364 struct list_head *list;
1365 struct channel *pch;
1366 struct sk_buff *frag;
1367 struct ppp_channel *chan;
1368
9c705260 1369 totspeed = 0; /*total bitrate of the bundle*/
fa44a73c
LS		 1370 nfree = 0; /* # channels which have no packet already queued */
1371 navail = 0; /* total # of usable channels (not deregistered) */
1372 nzero = 0; /* number of channels with zero speed associated*/
1373 totfree = 0; /*total # of channels available and
9c705260
GP		 1374 *having no queued packets before
1375 *starting the fragmentation*/
1376
1da177e4 1377 hdrlen = (ppp->flags & SC_MP_XSHORTSEQ)? MPHDRLEN_SSN: MPHDRLEN;
fa44a73c
LS		 1378 i = 0;
1379 list_for_each_entry(pch, &ppp->channels, clist) {
3429769b
DC		 1380 if (pch->chan) {
1381 pch->avail = 1;
1382 navail++;
1383 pch->speed = pch->chan->speed;
1384 } else {
1385 pch->avail = 0;
1386 }
fa44a73c 1387 if (pch->avail) {
b03efcfb 1388 if (skb_queue_empty(&pch->file.xq) ||
fa44a73c 1389 !pch->had_frag) {
9c705260
GP		 1390 if (pch->speed == 0)
1391 nzero++;
1392 else
1393 totspeed += pch->speed;
1394
1395 pch->avail = 2;
1396 ++nfree;
1397 ++totfree;
1398 }
fa44a73c
LS		 1399 if (!pch->had_frag && i < ppp->nxchan)
1400 ppp->nxchan = i;
1da177e4 1401 }
516cd15f 1402 ++i;
1da177e4 1403 }
516cd15f 1404 /*
fa44a73c
LS		 1405 * Don't start sending this packet unless at least half of
1406 * the channels are free. This gives much better TCP
1407 * performance if we have a lot of channels.
516cd15f 1408 */
fa44a73c
LS		 1409 if (nfree == 0 || nfree < navail / 2)
1410 return 0; /* can't take now, leave it in xmit_pending */
1da177e4 1411
d39cd5e9 1412 /* Do protocol field compression */
fa44a73c
LS		 1413 p = skb->data;
1414 len = skb->len;
d39cd5e9 1415 if (*p == 0 && mp_protocol_compress) {
1da177e4
LT		 1416 ++p;
1417 --len;
1418 }
1419
9c705260 1420 totlen = len;
fa44a73c 1421 nbigger = len % nfree;
9c705260 1422
fa44a73c
LS		 1423 /* skip to the channel after the one we last used
1424 and start at that one */
81616c5a 1425 list = &ppp->channels;
fa44a73c 1426 for (i = 0; i < ppp->nxchan; ++i) {
1da177e4 1427 list = list->next;
fa44a73c
LS		 1428 if (list == &ppp->channels) {
1429 i = 0;
1da177e4
LT		 1430 break;
1431 }
1432 }
1433
fa44a73c 1434 /* create a fragment for each channel */
1da177e4 1435 bits = B;
fa44a73c 1436 while (len > 0) {
1da177e4 1437 list = list->next;
fa44a73c
LS		 1438 if (list == &ppp->channels) {
1439 i = 0;
1da177e4
LT		 1440 continue;
1441 }
fa44a73c 1442 pch = list_entry(list, struct channel, clist);
1da177e4
LT		 1443 ++i;
1444 if (!pch->avail)
1445 continue;
1446
516cd15f 1447 /*
fa44a73c
LS		 1448 * Skip this channel if it has a fragment pending already and
1449 * we haven't given a fragment to all of the free channels.
516cd15f
PM		 1450 */
1451 if (pch->avail == 1) {
fa44a73c 1452 if (nfree > 0)
516cd15f
PM		 1453 continue;
1454 } else {
516cd15f
PM		 1455 pch->avail = 1;
1456 }
1457
1da177e4
LT		 1458 /* check the channel's mtu and whether it is still attached. */
1459 spin_lock_bh(&pch->downl);
516cd15f 1460 if (pch->chan == NULL) {
fa44a73c 1461 /* can't use this channel, it's being deregistered */
9c705260
GP		 1462 if (pch->speed == 0)
1463 nzero--;
1464 else
fa44a73c 1465 totspeed -= pch->speed;
9c705260 1466
1da177e4
LT		 1467 spin_unlock_bh(&pch->downl);
1468 pch->avail = 0;
9c705260
GP		 1469 totlen = len;
1470 totfree--;
1471 nfree--;
fa44a73c 1472 if (--navail == 0)
1da177e4
LT		 1473 break;
1474 continue;
1475 }
1476
1477 /*
9c705260 1478 *if the channel speed is not set divide
fa44a73c 1479 *the packet evenly among the free channels;
9c705260
GP		 1480 *otherwise divide it according to the speed
1481 *of the channel we are going to transmit on
1482 */
886f9fe6 1483 flen = len;
a53a8b56
BM		 1484 if (nfree > 0) {
1485 if (pch->speed == 0) {
536e00e5 1486 flen = len/nfree;
a53a8b56
BM		 1487 if (nbigger > 0) {
1488 flen++;
1489 nbigger--;
1490 }
1491 } else {
1492 flen = (((totfree - nzero)*(totlen + hdrlen*totfree)) /
1493 ((totspeed*totfree)/pch->speed)) - hdrlen;
1494 if (nbigger > 0) {
1495 flen += ((totfree - nzero)*pch->speed)/totspeed;
1496 nbigger -= ((totfree - nzero)*pch->speed)/
9c705260 1497 totspeed;
a53a8b56 1498 }
9c705260 1499 }
a53a8b56 1500 nfree--;
9c705260 1501 }
9c705260
GP		 1502
1503 /*
fa44a73c 1504 *check if we are on the last channel or
25985edc 1505 *we exceded the length of the data to
9c705260
GP		 1506 *fragment
1507 */
a53a8b56 1508 if ((nfree <= 0) || (flen > len))
9c705260
GP		 1509 flen = len;
1510 /*
1511 *it is not worth to tx on slow channels:
1512 *in that case from the resulting flen according to the
1513 *above formula will be equal or less than zero.
1514 *Skip the channel in this case
1da177e4 1515 */
fa44a73c 1516 if (flen <= 0) {
9c705260
GP		 1517 pch->avail = 2;
1518 spin_unlock_bh(&pch->downl);
1519 continue;
1520 }
1521
22e83a29
HW		 1522 /*
1523 * hdrlen includes the 2-byte PPP protocol field, but the
1524 * MTU counts only the payload excluding the protocol field.
1525 * (RFC1661 Section 2)
1526 */
1527 mtu = pch->chan->mtu - (hdrlen - 2);
fa44a73c
LS		 1528 if (mtu < 4)
1529 mtu = 4;
516cd15f
PM		 1530 if (flen > mtu)
1531 flen = mtu;
fa44a73c
LS		 1532 if (flen == len)
1533 bits |= E;
1534 frag = alloc_skb(flen + hdrlen + (flen == 0), GFP_ATOMIC);
cd228d54 1535 if (!frag)
516cd15f 1536 goto noskb;
fa44a73c 1537 q = skb_put(frag, flen + hdrlen);
516cd15f 1538
fa44a73c 1539 /* make the MP header */
96545aeb 1540 put_unaligned_be16(PPP_MP, q);
516cd15f 1541 if (ppp->flags & SC_MP_XSHORTSEQ) {
fa44a73c 1542 q[2] = bits + ((ppp->nxseq >> 8) & 0xf);
516cd15f
PM		 1543 q[3] = ppp->nxseq;
1544 } else {
1545 q[2] = bits;
1546 q[3] = ppp->nxseq >> 16;
1547 q[4] = ppp->nxseq >> 8;
1548 q[5] = ppp->nxseq;
1da177e4 1549 }
516cd15f 1550
9c705260 1551 memcpy(q + hdrlen, p, flen);
516cd15f
PM		 1552
1553 /* try to send it down the channel */
1554 chan = pch->chan;
fa44a73c 1555 if (!skb_queue_empty(&pch->file.xq) ||
9c705260 1556 !chan->ops->start_xmit(chan, frag))
516cd15f 1557 skb_queue_tail(&pch->file.xq, frag);
fa44a73c 1558 pch->had_frag = 1;
516cd15f 1559 p += flen;
fa44a73c 1560 len -= flen;
516cd15f
PM		 1561 ++ppp->nxseq;
1562 bits = 0;
1da177e4 1563 spin_unlock_bh(&pch->downl);
516cd15f 1564 }
fa44a73c 1565 ppp->nxchan = i;
1da177e4
LT		 1566
1567 return 1;
1568
1569 noskb:
1570 spin_unlock_bh(&pch->downl);
1571 if (ppp->debug & 1)
b48f8c23 1572 netdev_err(ppp->dev, "PPP: no memory (fragment)\n");
8c0469cd 1573 ++ppp->dev->stats.tx_errors;
1da177e4
LT		 1574 ++ppp->nxseq;
1575 return 1; /* abandon the frame */
1576}
1577#endif /* CONFIG_PPP_MULTILINK */
1578
1579/*
1580 * Try to send data out on a channel.
1581 */
1582static void
1583ppp_channel_push(struct channel *pch)
1584{
1585 struct sk_buff *skb;
1586 struct ppp *ppp;
1587
1588 spin_lock_bh(&pch->downl);
cd228d54 1589 if (pch->chan) {
b03efcfb 1590 while (!skb_queue_empty(&pch->file.xq)) {
1da177e4
LT		 1591 skb = skb_dequeue(&pch->file.xq);
1592 if (!pch->chan->ops->start_xmit(pch->chan, skb)) {
1593 /* put the packet back and try again later */
1594 skb_queue_head(&pch->file.xq, skb);
1595 break;
1596 }
1597 }
1598 } else {
1599 /* channel got deregistered */
1600 skb_queue_purge(&pch->file.xq);
1601 }
1602 spin_unlock_bh(&pch->downl);
1603 /* see if there is anything from the attached unit to be sent */
b03efcfb 1604 if (skb_queue_empty(&pch->file.xq)) {
1da177e4
LT		 1605 read_lock_bh(&pch->upl);
1606 ppp = pch->ppp;
cd228d54 1607 if (ppp)
1da177e4
LT		 1608 ppp_xmit_process(ppp);
1609 read_unlock_bh(&pch->upl);
1610 }
1611}
1612
1613/*
1614 * Receive-side routines.
1615 */
1616
a00eac0c
DM		 1617struct ppp_mp_skb_parm {
1618 u32 sequence;
1619 u8 BEbits;
1620};
1621#define PPP_MP_CB(skb) ((struct ppp_mp_skb_parm *)((skb)->cb))
1da177e4
LT		 1622
1623static inline void
1624ppp_do_recv(struct ppp *ppp, struct sk_buff *skb, struct channel *pch)
1625{
1626 ppp_recv_lock(ppp);
739840d5 1627 if (!ppp->closing)
1da177e4
LT		 1628 ppp_receive_frame(ppp, skb, pch);
1629 else
1630 kfree_skb(skb);
1631 ppp_recv_unlock(ppp);
1632}
1633
1634void
1635ppp_input(struct ppp_channel *chan, struct sk_buff *skb)
1636{
1637 struct channel *pch = chan->ppp;
1638 int proto;
1639
ea8420e9 1640 if (!pch) {
1da177e4
LT		 1641 kfree_skb(skb);
1642 return;
1643 }
516cd15f 1644
1da177e4 1645 read_lock_bh(&pch->upl);
ea8420e9
SA		 1646 if (!pskb_may_pull(skb, 2)) {
1647 kfree_skb(skb);
1648 if (pch->ppp) {
1649 ++pch->ppp->dev->stats.rx_length_errors;
1650 ppp_receive_error(pch->ppp);
1651 }
1652 goto done;
1653 }
1654
1655 proto = PPP_PROTO(skb);
cd228d54 1656 if (!pch->ppp || proto >= 0xc000 || proto == PPP_CCPFRAG) {
1da177e4
LT		 1657 /* put it on the channel queue */
1658 skb_queue_tail(&pch->file.rq, skb);
1659 /* drop old frames if queue too long */
8e95a202
JP		 1660 while (pch->file.rq.qlen > PPP_MAX_RQLEN &&
1661 (skb = skb_dequeue(&pch->file.rq)))
1da177e4
LT		 1662 kfree_skb(skb);
1663 wake_up_interruptible(&pch->file.rwait);
1664 } else {
1665 ppp_do_recv(pch->ppp, skb, pch);
1666 }
ea8420e9
SA		 1667
1668done:
1da177e4
LT		 1669 read_unlock_bh(&pch->upl);
1670}
1671
1672/* Put a 0-length skb in the receive queue as an error indication */
1673void
1674ppp_input_error(struct ppp_channel *chan, int code)
1675{
1676 struct channel *pch = chan->ppp;
1677 struct sk_buff *skb;
1678
cd228d54 1679 if (!pch)
1da177e4
LT		 1680 return;
1681
1682 read_lock_bh(&pch->upl);
cd228d54 1683 if (pch->ppp) {
1da177e4 1684 skb = alloc_skb(0, GFP_ATOMIC);
cd228d54 1685 if (skb) {
1da177e4
LT		 1686 skb->len = 0; /* probably unnecessary */
1687 skb->cb[0] = code;
1688 ppp_do_recv(pch->ppp, skb, pch);
1689 }
1690 }
1691 read_unlock_bh(&pch->upl);
1692}
1693
1694/*
1695 * We come in here to process a received frame.
1696 * The receive side of the ppp unit is locked.
1697 */
1698static void
1699ppp_receive_frame(struct ppp *ppp, struct sk_buff *skb, struct channel *pch)
1700{
ea8420e9
SA		 1701 /* note: a 0-length skb is used as an error indication */
1702 if (skb->len > 0) {
1da177e4
LT		 1703#ifdef CONFIG_PPP_MULTILINK
1704 /* XXX do channel-level decompression here */
1705 if (PPP_PROTO(skb) == PPP_MP)
1706 ppp_receive_mp_frame(ppp, skb, pch);
1707 else
1708#endif /* CONFIG_PPP_MULTILINK */
1709 ppp_receive_nonmp_frame(ppp, skb);
ea8420e9
SA		 1710 } else {
1711 kfree_skb(skb);
1712 ppp_receive_error(ppp);
1da177e4 1713 }
1da177e4
LT		 1714}
1715
1716static void
1717ppp_receive_error(struct ppp *ppp)
1718{
8c0469cd 1719 ++ppp->dev->stats.rx_errors;
cd228d54 1720 if (ppp->vj)
1da177e4
LT		 1721 slhc_toss(ppp->vj);
1722}
1723
1724static void
1725ppp_receive_nonmp_frame(struct ppp *ppp, struct sk_buff *skb)
1726{
1727 struct sk_buff *ns;
1728 int proto, len, npi;
1729
1730 /*
1731 * Decompress the frame, if compressed.
1732 * Note that some decompressors need to see uncompressed frames
1733 * that come in as well as compressed frames.
1734 */
8e95a202
JP		 1735 if (ppp->rc_state && (ppp->rstate & SC_DECOMP_RUN) &&
1736 (ppp->rstate & (SC_DC_FERROR | SC_DC_ERROR)) == 0)
1da177e4
LT		 1737 skb = ppp_decompress_frame(ppp, skb);
1738
b3f9b92a
MD		 1739 if (ppp->flags & SC_MUST_COMP && ppp->rstate & SC_DC_FERROR)
1740 goto err;
1741
1da177e4
LT		 1742 proto = PPP_PROTO(skb);
1743 switch (proto) {
1744 case PPP_VJC_COMP:
1745 /* decompress VJ compressed packets */
cd228d54 1746 if (!ppp->vj || (ppp->flags & SC_REJ_COMP_TCP))
1da177e4
LT		 1747 goto err;
1748
2a38b775 1749 if (skb_tailroom(skb) < 124 || skb_cloned(skb)) {
1da177e4
LT		 1750 /* copy to a new sk_buff with more tailroom */
1751 ns = dev_alloc_skb(skb->len + 128);
cd228d54 1752 if (!ns) {
b48f8c23
DM		 1753 netdev_err(ppp->dev, "PPP: no memory "
1754 "(VJ decomp)\n");
1da177e4
LT		 1755 goto err;
1756 }
1757 skb_reserve(ns, 2);
1758 skb_copy_bits(skb, 0, skb_put(ns, skb->len), skb->len);
968d7018 1759 consume_skb(skb);
1da177e4
LT		 1760 skb = ns;
1761 }
e3f749c4
HX		 1762 else
1763 skb->ip_summed = CHECKSUM_NONE;
1da177e4
LT		 1764
1765 len = slhc_uncompress(ppp->vj, skb->data + 2, skb->len - 2);
1766 if (len <= 0) {
b48f8c23
DM		 1767 netdev_printk(KERN_DEBUG, ppp->dev,
1768 "PPP: VJ decompression error\n");
1da177e4
LT		 1769 goto err;
1770 }
1771 len += 2;
1772 if (len > skb->len)
1773 skb_put(skb, len - skb->len);
1774 else if (len < skb->len)
1775 skb_trim(skb, len);
1776 proto = PPP_IP;
1777 break;
1778
1779 case PPP_VJC_UNCOMP:
cd228d54 1780 if (!ppp->vj || (ppp->flags & SC_REJ_COMP_TCP))
1da177e4 1781 goto err;
6aa20a22 1782
1da177e4
LT		 1783 /* Until we fix the decompressor need to make sure
1784 * data portion is linear.
1785 */
6aa20a22 1786 if (!pskb_may_pull(skb, skb->len))
1da177e4
LT		 1787 goto err;
1788
1789 if (slhc_remember(ppp->vj, skb->data + 2, skb->len - 2) <= 0) {
b48f8c23 1790 netdev_err(ppp->dev, "PPP: VJ uncompressed error\n");
1da177e4
LT		 1791 goto err;
1792 }
1793 proto = PPP_IP;
1794 break;
1795
1796 case PPP_CCP:
1797 ppp_ccp_peek(ppp, skb, 1);
1798 break;
1799 }
1800
e51f6ff3
KG		 1801 ++ppp->stats64.rx_packets;
1802 ppp->stats64.rx_bytes += skb->len - 2;
1da177e4
LT		 1803
1804 npi = proto_to_npindex(proto);
1805 if (npi < 0) {
1806 /* control or unknown frame - pass it to pppd */
1807 skb_queue_tail(&ppp->file.rq, skb);
1808 /* limit queue length by dropping old frames */
8e95a202
JP		 1809 while (ppp->file.rq.qlen > PPP_MAX_RQLEN &&
1810 (skb = skb_dequeue(&ppp->file.rq)))
1da177e4
LT		 1811 kfree_skb(skb);
1812 /* wake up any process polling or blocking on read */
1813 wake_up_interruptible(&ppp->file.rwait);
1814
1815 } else {
1816 /* network protocol frame - give it to the kernel */
1817
1818#ifdef CONFIG_PPP_FILTER
1819 /* check if the packet passes the pass and active filters */
1820 /* the filter instructions are constructed assuming
1821 a four-byte PPP header on each packet */
2a38b775 1822 if (ppp->pass_filter || ppp->active_filter) {
14bbd6a5 1823 if (skb_unclone(skb, GFP_ATOMIC))
2a38b775
HX		 1824 goto err;
1825
1826 *skb_push(skb, 2) = 0;
8e95a202 1827 if (ppp->pass_filter &&
568f194e 1828 SK_RUN_FILTER(ppp->pass_filter, skb) == 0) {
2a38b775 1829 if (ppp->debug & 1)
b48f8c23
DM		 1830 netdev_printk(KERN_DEBUG, ppp->dev,
1831 "PPP: inbound frame "
1832 "not passed\n");
2a38b775
HX		 1833 kfree_skb(skb);
1834 return;
1835 }
8e95a202 1836 if (!(ppp->active_filter &&
568f194e 1837 SK_RUN_FILTER(ppp->active_filter, skb) == 0))
2a38b775
HX		 1838 ppp->last_recv = jiffies;
1839 __skb_pull(skb, 2);
1840 } else
1da177e4 1841#endif /* CONFIG_PPP_FILTER */
2a38b775 1842 ppp->last_recv = jiffies;
1da177e4 1843
8e95a202
JP		 1844 if ((ppp->dev->flags & IFF_UP) == 0 ||
1845 ppp->npmode[npi] != NPMODE_PASS) {
1da177e4
LT		 1846 kfree_skb(skb);
1847 } else {
cbb042f9
HX		 1848 /* chop off protocol */
1849 skb_pull_rcsum(skb, 2);
1da177e4
LT		 1850 skb->dev = ppp->dev;
1851 skb->protocol = htons(npindex_to_ethertype[npi]);
459a98ed 1852 skb_reset_mac_header(skb);
1da177e4 1853 netif_rx(skb);
1da177e4
LT		 1854 }
1855 }
1856 return;
1857
1858 err:
1859 kfree_skb(skb);
1860 ppp_receive_error(ppp);
1861}
1862
1863static struct sk_buff *
1864ppp_decompress_frame(struct ppp *ppp, struct sk_buff *skb)
1865{
1866 int proto = PPP_PROTO(skb);
1867 struct sk_buff *ns;
1868 int len;
1869
1870 /* Until we fix all the decompressor's need to make sure
1871 * data portion is linear.
1872 */
1873 if (!pskb_may_pull(skb, skb->len))
1874 goto err;
1875
1876 if (proto == PPP_COMP) {
4b2a8fb3
KS		 1877 int obuff_size;
1878
1879 switch(ppp->rcomp->compress_proto) {
1880 case CI_MPPE:
1881 obuff_size = ppp->mru + PPP_HDRLEN + 1;
1882 break;
1883 default:
1884 obuff_size = ppp->mru + PPP_HDRLEN;
1885 break;
1886 }
1887
1888 ns = dev_alloc_skb(obuff_size);
cd228d54 1889 if (!ns) {
b48f8c23
DM		 1890 netdev_err(ppp->dev, "ppp_decompress_frame: "
1891 "no memory\n");
1da177e4
LT		 1892 goto err;
1893 }
1894 /* the decompressor still expects the A/C bytes in the hdr */
1895 len = ppp->rcomp->decompress(ppp->rc_state, skb->data - 2,
06c7af56 1896 skb->len + 2, ns->data, obuff_size);
1da177e4
LT		 1897 if (len < 0) {
1898 /* Pass the compressed frame to pppd as an
1899 error indication. */
1900 if (len == DECOMP_FATALERROR)
1901 ppp->rstate |= SC_DC_FERROR;
1902 kfree_skb(ns);
1903 goto err;
1904 }
1905
968d7018 1906 consume_skb(skb);
1da177e4
LT		 1907 skb = ns;
1908 skb_put(skb, len);
1909 skb_pull(skb, 2); /* pull off the A/C bytes */
1910
1911 } else {
1912 /* Uncompressed frame - pass to decompressor so it
1913 can update its dictionary if necessary. */
1914 if (ppp->rcomp->incomp)
1915 ppp->rcomp->incomp(ppp->rc_state, skb->data - 2,
1916 skb->len + 2);
1917 }
1918
1919 return skb;
1920
1921 err:
1922 ppp->rstate |= SC_DC_ERROR;
1923 ppp_receive_error(ppp);
1924 return skb;
1925}
1926
1927#ifdef CONFIG_PPP_MULTILINK
1928/*
1929 * Receive a multilink frame.
1930 * We put it on the reconstruction queue and then pull off
1931 * as many completed frames as we can.
1932 */
1933static void
1934ppp_receive_mp_frame(struct ppp *ppp, struct sk_buff *skb, struct channel *pch)
1935{
1936 u32 mask, seq;
81616c5a 1937 struct channel *ch;
1da177e4
LT		 1938 int mphdrlen = (ppp->flags & SC_MP_SHORTSEQ)? MPHDRLEN_SSN: MPHDRLEN;
1939
2a38b775 1940 if (!pskb_may_pull(skb, mphdrlen + 1) || ppp->mrru == 0)
1da177e4
LT		 1941 goto err; /* no good, throw it away */
1942
1943 /* Decode sequence number and begin/end bits */
1944 if (ppp->flags & SC_MP_SHORTSEQ) {
1945 seq = ((skb->data[2] & 0x0f) << 8) | skb->data[3];
1946 mask = 0xfff;
1947 } else {
1948 seq = (skb->data[3] << 16) | (skb->data[4] << 8)| skb->data[5];
1949 mask = 0xffffff;
1950 }
a00eac0c 1951 PPP_MP_CB(skb)->BEbits = skb->data[2];
1da177e4
LT		 1952 skb_pull(skb, mphdrlen); /* pull off PPP and MP headers */
1953
1954 /*
1955 * Do protocol ID decompression on the first fragment of each packet.
1956 */
a00eac0c 1957 if ((PPP_MP_CB(skb)->BEbits & B) && (skb->data[0] & 1))
1da177e4
LT		 1958 *skb_push(skb, 1) = 0;
1959
1960 /*
1961 * Expand sequence number to 32 bits, making it as close
1962 * as possible to ppp->minseq.
1963 */
1964 seq |= ppp->minseq & ~mask;
1965 if ((int)(ppp->minseq - seq) > (int)(mask >> 1))
1966 seq += mask + 1;
1967 else if ((int)(seq - ppp->minseq) > (int)(mask >> 1))
1968 seq -= mask + 1; /* should never happen */
a00eac0c 1969 PPP_MP_CB(skb)->sequence = seq;
1da177e4
LT		 1970 pch->lastseq = seq;
1971
1972 /*
1973 * If this packet comes before the next one we were expecting,
1974 * drop it.
1975 */
1976 if (seq_before(seq, ppp->nextseq)) {
1977 kfree_skb(skb);
8c0469cd 1978 ++ppp->dev->stats.rx_dropped;
1da177e4
LT		 1979 ppp_receive_error(ppp);
1980 return;
1981 }
1982
1983 /*
1984 * Reevaluate minseq, the minimum over all channels of the
1985 * last sequence number received on each channel. Because of
1986 * the increasing sequence number rule, we know that any fragment
1987 * before `minseq' which hasn't arrived is never going to arrive.
1988 * The list of channels can't change because we have the receive
1989 * side of the ppp unit locked.
1990 */
81616c5a 1991 list_for_each_entry(ch, &ppp->channels, clist) {
1da177e4
LT		 1992 if (seq_before(ch->lastseq, seq))
1993 seq = ch->lastseq;
1994 }
1995 if (seq_before(ppp->minseq, seq))
1996 ppp->minseq = seq;
1997
1998 /* Put the fragment on the reconstruction queue */
1999 ppp_mp_insert(ppp, skb);
2000
2001 /* If the queue is getting long, don't wait any longer for packets
2002 before the start of the queue. */
38ce7c73 2003 if (skb_queue_len(&ppp->mrq) >= PPP_MP_MAX_QLEN) {
c6b20d94 2004 struct sk_buff *mskb = skb_peek(&ppp->mrq);
a00eac0c
DM		 2005 if (seq_before(ppp->minseq, PPP_MP_CB(mskb)->sequence))
2006 ppp->minseq = PPP_MP_CB(mskb)->sequence;
38ce7c73 2007 }
1da177e4
LT		 2008
2009 /* Pull completed packets off the queue and receive them. */
82b3cc1a
BM		 2010 while ((skb = ppp_mp_reconstruct(ppp))) {
2011 if (pskb_may_pull(skb, 2))
2012 ppp_receive_nonmp_frame(ppp, skb);
2013 else {
2014 ++ppp->dev->stats.rx_length_errors;
2015 kfree_skb(skb);
2016 ppp_receive_error(ppp);
2017 }
2018 }
1da177e4
LT		 2019
2020 return;
2021
2022 err:
2023 kfree_skb(skb);
2024 ppp_receive_error(ppp);
2025}
2026
2027/*
2028 * Insert a fragment on the MP reconstruction queue.
2029 * The queue is ordered by increasing sequence number.
2030 */
2031static void
2032ppp_mp_insert(struct ppp *ppp, struct sk_buff *skb)
2033{
2034 struct sk_buff *p;
2035 struct sk_buff_head *list = &ppp->mrq;
a00eac0c 2036 u32 seq = PPP_MP_CB(skb)->sequence;
1da177e4
LT		 2037
2038 /* N.B. we don't need to lock the list lock because we have the
2039 ppp unit receive-side lock. */
13c9821e 2040 skb_queue_walk(list, p) {
a00eac0c 2041 if (seq_before(seq, PPP_MP_CB(p)->sequence))
1da177e4 2042 break;
13c9821e 2043 }
43f59c89 2044 __skb_queue_before(list, p, skb);
1da177e4
LT		 2045}
2046
2047/*
2048 * Reconstruct a packet from the MP fragment queue.
2049 * We go through increasing sequence numbers until we find a
2050 * complete packet, or we get to the sequence number for a fragment
2051 * which hasn't arrived but might still do so.
2052 */
3c582b30 2053static struct sk_buff *
1da177e4
LT		 2054ppp_mp_reconstruct(struct ppp *ppp)
2055{
2056 u32 seq = ppp->nextseq;
2057 u32 minseq = ppp->minseq;
2058 struct sk_buff_head *list = &ppp->mrq;
d52344a7 2059 struct sk_buff *p, *tmp;
1da177e4
LT		 2060 struct sk_buff *head, *tail;
2061 struct sk_buff *skb = NULL;
2062 int lost = 0, len = 0;
2063
2064 if (ppp->mrru == 0) /* do nothing until mrru is set */
2065 return NULL;
2066 head = list->next;
2067 tail = NULL;
d52344a7
DM		 2068 skb_queue_walk_safe(list, p, tmp) {
2069 again:
a00eac0c 2070 if (seq_before(PPP_MP_CB(p)->sequence, seq)) {
1da177e4 2071 /* this can't happen, anyway ignore the skb */
b48f8c23
DM		 2072 netdev_err(ppp->dev, "ppp_mp_reconstruct bad "
2073 "seq %u < %u\n",
2074 PPP_MP_CB(p)->sequence, seq);
d52344a7
DM		 2075 __skb_unlink(p, list);
2076 kfree_skb(p);
1da177e4
LT		 2077 continue;
2078 }
a00eac0c 2079 if (PPP_MP_CB(p)->sequence != seq) {
8a49ad6e 2080 u32 oldseq;
1da177e4
LT		 2081 /* Fragment `seq' is missing. If it is after
2082 minseq, it might arrive later, so stop here. */
2083 if (seq_after(seq, minseq))
2084 break;
2085 /* Fragment `seq' is lost, keep going. */
2086 lost = 1;
8a49ad6e 2087 oldseq = seq;
a00eac0c
DM		 2088 seq = seq_before(minseq, PPP_MP_CB(p)->sequence)?
2089 minseq + 1: PPP_MP_CB(p)->sequence;
8a49ad6e
BM		 2090
2091 if (ppp->debug & 1)
2092 netdev_printk(KERN_DEBUG, ppp->dev,
2093 "lost frag %u..%u\n",
2094 oldseq, seq-1);
2095
d52344a7 2096 goto again;
1da177e4
LT		 2097 }
2098
2099 /*
2100 * At this point we know that all the fragments from
2101 * ppp->nextseq to seq are either present or lost.
2102 * Also, there are no complete packets in the queue
2103 * that have no missing fragments and end before this
2104 * fragment.
2105 */
2106
2107 /* B bit set indicates this fragment starts a packet */
a00eac0c 2108 if (PPP_MP_CB(p)->BEbits & B) {
1da177e4
LT		 2109 head = p;
2110 lost = 0;
2111 len = 0;
2112 }
2113
2114 len += p->len;
2115
2116 /* Got a complete packet yet? */
a00eac0c
DM		 2117 if (lost == 0 && (PPP_MP_CB(p)->BEbits & E) &&
2118 (PPP_MP_CB(head)->BEbits & B)) {
1da177e4 2119 if (len > ppp->mrru + 2) {
8c0469cd 2120 ++ppp->dev->stats.rx_length_errors;
b48f8c23
DM		 2121 netdev_printk(KERN_DEBUG, ppp->dev,
2122 "PPP: reconstructed packet"
2123 " is too long (%d)\n", len);
1da177e4
LT		 2124 } else {
2125 tail = p;
2126 break;
2127 }
2128 ppp->nextseq = seq + 1;
2129 }
2130
2131 /*
2132 * If this is the ending fragment of a packet,
2133 * and we haven't found a complete valid packet yet,
2134 * we can discard up to and including this fragment.
2135 */
d52344a7
DM		 2136 if (PPP_MP_CB(p)->BEbits & E) {
2137 struct sk_buff *tmp2;
1da177e4 2138
d52344a7 2139 skb_queue_reverse_walk_from_safe(list, p, tmp2) {
8a49ad6e
BM		 2140 if (ppp->debug & 1)
2141 netdev_printk(KERN_DEBUG, ppp->dev,
2142 "discarding frag %u\n",
2143 PPP_MP_CB(p)->sequence);
d52344a7
DM		 2144 __skb_unlink(p, list);
2145 kfree_skb(p);
2146 }
2147 head = skb_peek(list);
2148 if (!head)
2149 break;
2150 }
1da177e4
LT		 2151 ++seq;
2152 }
2153
2154 /* If we have a complete packet, copy it all into one skb. */
2155 if (tail != NULL) {
2156 /* If we have discarded any fragments,
2157 signal a receive error. */
a00eac0c 2158 if (PPP_MP_CB(head)->sequence != ppp->nextseq) {
8a49ad6e
BM		 2159 skb_queue_walk_safe(list, p, tmp) {
2160 if (p == head)
2161 break;
2162 if (ppp->debug & 1)
2163 netdev_printk(KERN_DEBUG, ppp->dev,
2164 "discarding frag %u\n",
2165 PPP_MP_CB(p)->sequence);
2166 __skb_unlink(p, list);
2167 kfree_skb(p);
2168 }
2169
1da177e4 2170 if (ppp->debug & 1)
b48f8c23
DM		 2171 netdev_printk(KERN_DEBUG, ppp->dev,
2172 " missed pkts %u..%u\n",
2173 ppp->nextseq,
2174 PPP_MP_CB(head)->sequence-1);
8c0469cd 2175 ++ppp->dev->stats.rx_dropped;
1da177e4
LT		 2176 ppp_receive_error(ppp);
2177 }
2178
212bfb9e
DM		 2179 skb = head;
2180 if (head != tail) {
2181 struct sk_buff **fragpp = &skb_shinfo(skb)->frag_list;
2182 p = skb_queue_next(list, head);
2183 __skb_unlink(skb, list);
2184 skb_queue_walk_from_safe(list, p, tmp) {
2185 __skb_unlink(p, list);
2186 *fragpp = p;
2187 p->next = NULL;
2188 fragpp = &p->next;
2189
2190 skb->len += p->len;
2191 skb->data_len += p->len;
19c6c8f5 2192 skb->truesize += p->truesize;
212bfb9e
DM		 2193
2194 if (p == tail)
2195 break;
2196 }
2197 } else {
2198 __skb_unlink(skb, list);
2199 }
2200
a00eac0c 2201 ppp->nextseq = PPP_MP_CB(tail)->sequence + 1;
1da177e4
LT		 2202 }
2203
2204 return skb;
2205}
2206#endif /* CONFIG_PPP_MULTILINK */
2207
2208/*
2209 * Channel interface.
2210 */
2211
273ec51d
CG		 2212/* Create a new, unattached ppp channel. */
2213int ppp_register_channel(struct ppp_channel *chan)
2214{
2215 return ppp_register_net_channel(current->nsproxy->net_ns, chan);
2216}
2217
2218/* Create a new, unattached ppp channel for specified net. */
2219int ppp_register_net_channel(struct net *net, struct ppp_channel *chan)
1da177e4
LT		 2220{
2221 struct channel *pch;
273ec51d 2222 struct ppp_net *pn;
1da177e4 2223
d4274b51 2224 pch = kzalloc(sizeof(struct channel), GFP_KERNEL);
cd228d54 2225 if (!pch)
1da177e4 2226 return -ENOMEM;
273ec51d
CG		 2227
2228 pn = ppp_pernet(net);
2229
1da177e4
LT		 2230 pch->ppp = NULL;
2231 pch->chan = chan;
273ec51d 2232 pch->chan_net = net;
1da177e4
LT		 2233 chan->ppp = pch;
2234 init_ppp_file(&pch->file, CHANNEL);
2235 pch->file.hdrlen = chan->hdrlen;
2236#ifdef CONFIG_PPP_MULTILINK
2237 pch->lastseq = -1;
2238#endif /* CONFIG_PPP_MULTILINK */
2239 init_rwsem(&pch->chan_sem);
2240 spin_lock_init(&pch->downl);
2241 rwlock_init(&pch->upl);
273ec51d
CG		 2242
2243 spin_lock_bh(&pn->all_channels_lock);
2244 pch->file.index = ++pn->last_channel_index;
2245 list_add(&pch->list, &pn->new_channels);
1da177e4 2246 atomic_inc(&channel_count);
273ec51d
CG		 2247 spin_unlock_bh(&pn->all_channels_lock);
2248
1da177e4
LT		 2249 return 0;
2250}
2251
2252/*
2253 * Return the index of a channel.
2254 */
2255int ppp_channel_index(struct ppp_channel *chan)
2256{
2257 struct channel *pch = chan->ppp;
2258
cd228d54 2259 if (pch)
1da177e4
LT		 2260 return pch->file.index;
2261 return -1;
2262}
2263
2264/*
2265 * Return the PPP unit number to which a channel is connected.
2266 */
2267int ppp_unit_number(struct ppp_channel *chan)
2268{
2269 struct channel *pch = chan->ppp;
2270 int unit = -1;
2271
cd228d54 2272 if (pch) {
1da177e4 2273 read_lock_bh(&pch->upl);
cd228d54 2274 if (pch->ppp)
1da177e4
LT		 2275 unit = pch->ppp->file.index;
2276 read_unlock_bh(&pch->upl);
2277 }
2278 return unit;
2279}
2280
63f96072
JC		 2281/*
2282 * Return the PPP device interface name of a channel.
2283 */
2284char *ppp_dev_name(struct ppp_channel *chan)
2285{
2286 struct channel *pch = chan->ppp;
2287 char *name = NULL;
2288
2289 if (pch) {
2290 read_lock_bh(&pch->upl);
2291 if (pch->ppp && pch->ppp->dev)
2292 name = pch->ppp->dev->name;
2293 read_unlock_bh(&pch->upl);
2294 }
2295 return name;
2296}
2297
2298
1da177e4
LT		 2299/*
2300 * Disconnect a channel from the generic layer.
2301 * This must be called in process context.
2302 */
2303void
2304ppp_unregister_channel(struct ppp_channel *chan)
2305{
2306 struct channel *pch = chan->ppp;
273ec51d 2307 struct ppp_net *pn;
1da177e4 2308
cd228d54 2309 if (!pch)
1da177e4 2310 return; /* should never happen */
273ec51d 2311
1da177e4
LT		 2312 chan->ppp = NULL;
2313
2314 /*
2315 * This ensures that we have returned from any calls into the
2316 * the channel's start_xmit or ioctl routine before we proceed.
2317 */
2318 down_write(&pch->chan_sem);
2319 spin_lock_bh(&pch->downl);
2320 pch->chan = NULL;
2321 spin_unlock_bh(&pch->downl);
2322 up_write(&pch->chan_sem);
2323 ppp_disconnect_channel(pch);
273ec51d
CG		 2324
2325 pn = ppp_pernet(pch->chan_net);
2326 spin_lock_bh(&pn->all_channels_lock);
1da177e4 2327 list_del(&pch->list);
273ec51d
CG		 2328 spin_unlock_bh(&pn->all_channels_lock);
2329
1da177e4
LT		 2330 pch->file.dead = 1;
2331 wake_up_interruptible(&pch->file.rwait);
2332 if (atomic_dec_and_test(&pch->file.refcnt))
2333 ppp_destroy_channel(pch);
2334}
2335
2336/*
2337 * Callback from a channel when it can accept more to transmit.
2338 * This should be called at BH/softirq level, not interrupt level.
2339 */
2340void
2341ppp_output_wakeup(struct ppp_channel *chan)
2342{
2343 struct channel *pch = chan->ppp;
2344
cd228d54 2345 if (!pch)
1da177e4
LT		 2346 return;
2347 ppp_channel_push(pch);
2348}
2349
2350/*
2351 * Compression control.
2352 */
2353
2354/* Process the PPPIOCSCOMPRESS ioctl. */
2355static int
2356ppp_set_compress(struct ppp *ppp, unsigned long arg)
2357{
2358 int err;
2359 struct compressor *cp, *ocomp;
2360 struct ppp_option_data data;
2361 void *state, *ostate;
2362 unsigned char ccp_option[CCP_MAX_OPTION_LENGTH];
2363
2364 err = -EFAULT;
8e95a202
JP		 2365 if (copy_from_user(&data, (void __user *) arg, sizeof(data)) ||
2366 (data.length <= CCP_MAX_OPTION_LENGTH &&
2367 copy_from_user(ccp_option, (void __user *) data.ptr, data.length)))
1da177e4
LT		 2368 goto out;
2369 err = -EINVAL;
8e95a202
JP		 2370 if (data.length > CCP_MAX_OPTION_LENGTH ||
2371 ccp_option[1] < 2 || ccp_option[1] > data.length)
1da177e4
LT		 2372 goto out;
2373
a65e5d78
JB		 2374 cp = try_then_request_module(
2375 find_compressor(ccp_option[0]),
2376 "ppp-compress-%d", ccp_option[0]);
cd228d54 2377 if (!cp)
1da177e4
LT		 2378 goto out;
2379
2380 err = -ENOBUFS;
2381 if (data.transmit) {
2382 state = cp->comp_alloc(ccp_option, data.length);
cd228d54 2383 if (state) {
1da177e4
LT		 2384 ppp_xmit_lock(ppp);
2385 ppp->xstate &= ~SC_COMP_RUN;
2386 ocomp = ppp->xcomp;
2387 ostate = ppp->xc_state;
2388 ppp->xcomp = cp;
2389 ppp->xc_state = state;
2390 ppp_xmit_unlock(ppp);
cd228d54 2391 if (ostate) {
1da177e4
LT		 2392 ocomp->comp_free(ostate);
2393 module_put(ocomp->owner);
2394 }
2395 err = 0;
2396 } else
2397 module_put(cp->owner);
2398
2399 } else {
2400 state = cp->decomp_alloc(ccp_option, data.length);
cd228d54 2401 if (state) {
1da177e4
LT		 2402 ppp_recv_lock(ppp);
2403 ppp->rstate &= ~SC_DECOMP_RUN;
2404 ocomp = ppp->rcomp;
2405 ostate = ppp->rc_state;
2406 ppp->rcomp = cp;
2407 ppp->rc_state = state;
2408 ppp_recv_unlock(ppp);
cd228d54 2409 if (ostate) {
1da177e4
LT		 2410 ocomp->decomp_free(ostate);
2411 module_put(ocomp->owner);
2412 }
2413 err = 0;
2414 } else
2415 module_put(cp->owner);
2416 }
2417
2418 out:
2419 return err;
2420}
2421
2422/*
2423 * Look at a CCP packet and update our state accordingly.
2424 * We assume the caller has the xmit or recv path locked.
2425 */
2426static void
2427ppp_ccp_peek(struct ppp *ppp, struct sk_buff *skb, int inbound)
2428{
2429 unsigned char *dp;
2430 int len;
2431
2432 if (!pskb_may_pull(skb, CCP_HDRLEN + 2))
2433 return; /* no header */
2434 dp = skb->data + 2;
2435
2436 switch (CCP_CODE(dp)) {
2437 case CCP_CONFREQ:
2438
6aa20a22 2439 /* A ConfReq starts negotiation of compression
1da177e4
LT		 2440 * in one direction of transmission,
2441 * and hence brings it down...but which way?
2442 *
2443 * Remember:
2444 * A ConfReq indicates what the sender would like to receive
2445 */
2446 if(inbound)
2447 /* He is proposing what I should send */
2448 ppp->xstate &= ~SC_COMP_RUN;
6aa20a22 2449 else
1da177e4
LT		 2450 /* I am proposing to what he should send */
2451 ppp->rstate &= ~SC_DECOMP_RUN;
6aa20a22 2452
1da177e4 2453 break;
6aa20a22 2454
1da177e4
LT		 2455 case CCP_TERMREQ:
2456 case CCP_TERMACK:
2457 /*
6aa20a22 2458 * CCP is going down, both directions of transmission
1da177e4
LT		 2459 */
2460 ppp->rstate &= ~SC_DECOMP_RUN;
2461 ppp->xstate &= ~SC_COMP_RUN;
2462 break;
2463
2464 case CCP_CONFACK:
2465 if ((ppp->flags & (SC_CCP_OPEN | SC_CCP_UP)) != SC_CCP_OPEN)
2466 break;
2467 len = CCP_LENGTH(dp);
2468 if (!pskb_may_pull(skb, len + 2))
2469 return; /* too short */
2470 dp += CCP_HDRLEN;
2471 len -= CCP_HDRLEN;
2472 if (len < CCP_OPT_MINLEN || len < CCP_OPT_LENGTH(dp))
2473 break;
2474 if (inbound) {
2475 /* we will start receiving compressed packets */
cd228d54 2476 if (!ppp->rc_state)
1da177e4
LT		 2477 break;
2478 if (ppp->rcomp->decomp_init(ppp->rc_state, dp, len,
2479 ppp->file.index, 0, ppp->mru, ppp->debug)) {
2480 ppp->rstate |= SC_DECOMP_RUN;
2481 ppp->rstate &= ~(SC_DC_ERROR | SC_DC_FERROR);
2482 }
2483 } else {
2484 /* we will soon start sending compressed packets */
cd228d54 2485 if (!ppp->xc_state)
1da177e4
LT		 2486 break;
2487 if (ppp->xcomp->comp_init(ppp->xc_state, dp, len,
2488 ppp->file.index, 0, ppp->debug))
2489 ppp->xstate |= SC_COMP_RUN;
2490 }
2491 break;
2492
2493 case CCP_RESETACK:
2494 /* reset the [de]compressor */
2495 if ((ppp->flags & SC_CCP_UP) == 0)
2496 break;
2497 if (inbound) {
2498 if (ppp->rc_state && (ppp->rstate & SC_DECOMP_RUN)) {
2499 ppp->rcomp->decomp_reset(ppp->rc_state);
2500 ppp->rstate &= ~SC_DC_ERROR;
2501 }
2502 } else {
2503 if (ppp->xc_state && (ppp->xstate & SC_COMP_RUN))
2504 ppp->xcomp->comp_reset(ppp->xc_state);
2505 }
2506 break;
2507 }
2508}
2509
2510/* Free up compression resources. */
2511static void
2512ppp_ccp_closed(struct ppp *ppp)
2513{
2514 void *xstate, *rstate;
2515 struct compressor *xcomp, *rcomp;
2516
2517 ppp_lock(ppp);
2518 ppp->flags &= ~(SC_CCP_OPEN | SC_CCP_UP);
2519 ppp->xstate = 0;
2520 xcomp = ppp->xcomp;
2521 xstate = ppp->xc_state;
2522 ppp->xc_state = NULL;
2523 ppp->rstate = 0;
2524 rcomp = ppp->rcomp;
2525 rstate = ppp->rc_state;
2526 ppp->rc_state = NULL;
2527 ppp_unlock(ppp);
2528
2529 if (xstate) {
2530 xcomp->comp_free(xstate);
2531 module_put(xcomp->owner);
2532 }
2533 if (rstate) {
2534 rcomp->decomp_free(rstate);
2535 module_put(rcomp->owner);
2536 }
2537}
2538
2539/* List of compressors. */
2540static LIST_HEAD(compressor_list);
2541static DEFINE_SPINLOCK(compressor_list_lock);
2542
2543struct compressor_entry {
2544 struct list_head list;
2545 struct compressor *comp;
2546};
2547
2548static struct compressor_entry *
2549find_comp_entry(int proto)
2550{
2551 struct compressor_entry *ce;
1da177e4 2552
81616c5a 2553 list_for_each_entry(ce, &compressor_list, list) {
1da177e4
LT		 2554 if (ce->comp->compress_proto == proto)
2555 return ce;
2556 }
2557 return NULL;
2558}
2559
2560/* Register a compressor */
2561int
2562ppp_register_compressor(struct compressor *cp)
2563{
2564 struct compressor_entry *ce;
2565 int ret;
2566 spin_lock(&compressor_list_lock);
2567 ret = -EEXIST;
cd228d54 2568 if (find_comp_entry(cp->compress_proto))
1da177e4
LT		 2569 goto out;
2570 ret = -ENOMEM;
2571 ce = kmalloc(sizeof(struct compressor_entry), GFP_ATOMIC);
cd228d54 2572 if (!ce)
1da177e4
LT		 2573 goto out;
2574 ret = 0;
2575 ce->comp = cp;
2576 list_add(&ce->list, &compressor_list);
2577 out:
2578 spin_unlock(&compressor_list_lock);
2579 return ret;
2580}
2581
2582/* Unregister a compressor */
2583void
2584ppp_unregister_compressor(struct compressor *cp)
2585{
2586 struct compressor_entry *ce;
2587
2588 spin_lock(&compressor_list_lock);
2589 ce = find_comp_entry(cp->compress_proto);
cd228d54 2590 if (ce && ce->comp == cp) {
1da177e4
LT		 2591 list_del(&ce->list);
2592 kfree(ce);
2593 }
2594 spin_unlock(&compressor_list_lock);
2595}
2596
2597/* Find a compressor. */
2598static struct compressor *
2599find_compressor(int type)
2600{
2601 struct compressor_entry *ce;
2602 struct compressor *cp = NULL;
2603
2604 spin_lock(&compressor_list_lock);
2605 ce = find_comp_entry(type);
cd228d54 2606 if (ce) {
1da177e4
LT		 2607 cp = ce->comp;
2608 if (!try_module_get(cp->owner))
2609 cp = NULL;
2610 }
2611 spin_unlock(&compressor_list_lock);
2612 return cp;
2613}
2614
2615/*
2616 * Miscelleneous stuff.
2617 */
2618
2619static void
2620ppp_get_stats(struct ppp *ppp, struct ppp_stats *st)
2621{
2622 struct slcompress *vj = ppp->vj;
2623
2624 memset(st, 0, sizeof(*st));
e51f6ff3 2625 st->p.ppp_ipackets = ppp->stats64.rx_packets;
8c0469cd 2626 st->p.ppp_ierrors = ppp->dev->stats.rx_errors;
e51f6ff3
KG		 2627 st->p.ppp_ibytes = ppp->stats64.rx_bytes;
2628 st->p.ppp_opackets = ppp->stats64.tx_packets;
8c0469cd 2629 st->p.ppp_oerrors = ppp->dev->stats.tx_errors;
e51f6ff3 2630 st->p.ppp_obytes = ppp->stats64.tx_bytes;
cd228d54 2631 if (!vj)
1da177e4
LT		 2632 return;
2633 st->vj.vjs_packets = vj->sls_o_compressed + vj->sls_o_uncompressed;
2634 st->vj.vjs_compressed = vj->sls_o_compressed;
2635 st->vj.vjs_searches = vj->sls_o_searches;
2636 st->vj.vjs_misses = vj->sls_o_misses;
2637 st->vj.vjs_errorin = vj->sls_i_error;
2638 st->vj.vjs_tossed = vj->sls_i_tossed;
2639 st->vj.vjs_uncompressedin = vj->sls_i_uncompressed;
2640 st->vj.vjs_compressedin = vj->sls_i_compressed;
2641}
2642
2643/*
2644 * Stuff for handling the lists of ppp units and channels
2645 * and for initialization.
2646 */
2647
2648/*
2649 * Create a new ppp interface unit. Fails if it can't allocate memory
2650 * or if there is already a unit with the requested number.
2651 * unit == -1 means allocate a new number.
2652 */
2653static struct ppp *
273ec51d 2654ppp_create_interface(struct net *net, int unit, int *retp)
1da177e4
LT		 2655{
2656 struct ppp *ppp;
273ec51d 2657 struct ppp_net *pn;
1da177e4
LT		 2658 struct net_device *dev = NULL;
2659 int ret = -ENOMEM;
2660 int i;
2661
c8019bf3 2662 dev = alloc_netdev(sizeof(struct ppp), "", ppp_setup);
1da177e4
LT		 2663 if (!dev)
2664 goto out1;
1da177e4 2665
273ec51d
CG		 2666 pn = ppp_pernet(net);
2667
c8019bf3
WC		 2668 ppp = netdev_priv(dev);
2669 ppp->dev = dev;
1da177e4
LT		 2670 ppp->mru = PPP_MRU;
2671 init_ppp_file(&ppp->file, INTERFACE);
2672 ppp->file.hdrlen = PPP_HDRLEN - 2; /* don't count proto bytes */
2673 for (i = 0; i < NUM_NP; ++i)
2674 ppp->npmode[i] = NPMODE_PASS;
2675 INIT_LIST_HEAD(&ppp->channels);
2676 spin_lock_init(&ppp->rlock);
2677 spin_lock_init(&ppp->wlock);
2678#ifdef CONFIG_PPP_MULTILINK
2679 ppp->minseq = -1;
2680 skb_queue_head_init(&ppp->mrq);
2681#endif /* CONFIG_PPP_MULTILINK */
568f194e
DB		 2682#ifdef CONFIG_PPP_FILTER
2683 ppp->pass_filter = NULL;
2684 ppp->active_filter = NULL;
2685#endif /* CONFIG_PPP_FILTER */
1da177e4 2686
273ec51d
CG		 2687 /*
2688 * drum roll: don't forget to set
2689 * the net device is belong to
2690 */
2691 dev_net_set(dev, net);
2692
273ec51d 2693 mutex_lock(&pn->all_ppp_mutex);
7a95d267
CG		 2694
2695 if (unit < 0) {
273ec51d 2696 unit = unit_get(&pn->units_idr, ppp);
7a95d267 2697 if (unit < 0) {
bcc70bb3 2698 ret = unit;
7a95d267
CG		 2699 goto out2;
2700 }
2701 } else {
bcc70bb3 2702 ret = -EEXIST;
273ec51d 2703 if (unit_find(&pn->units_idr, unit))
7a95d267 2704 goto out2; /* unit already exists */
85997576
CG		 2705 /*
2706 * if caller need a specified unit number
2707 * lets try to satisfy him, otherwise --
2708 * he should better ask us for new unit number
2709 *
2710 * NOTE: yes I know that returning EEXIST it's not
2711 * fair but at least pppd will ask us to allocate
2712 * new unit in this case so user is happy :)
2713 */
273ec51d 2714 unit = unit_set(&pn->units_idr, ppp, unit);
85997576 2715 if (unit < 0)
7a95d267 2716 goto out2;
7a95d267 2717 }
1da177e4
LT		 2718
2719 /* Initialize the new ppp unit */
2720 ppp->file.index = unit;
2721 sprintf(dev->name, "ppp%d", unit);
2722
2723 ret = register_netdev(dev);
2724 if (ret != 0) {
273ec51d 2725 unit_put(&pn->units_idr, unit);
b48f8c23
DM		 2726 netdev_err(ppp->dev, "PPP: couldn't register device %s (%d)\n",
2727 dev->name, ret);
1da177e4
LT		 2728 goto out2;
2729 }
2730
273ec51d
CG		 2731 ppp->ppp_net = net;
2732
1da177e4 2733 atomic_inc(&ppp_unit_count);
273ec51d 2734 mutex_unlock(&pn->all_ppp_mutex);
7a95d267 2735
1da177e4
LT		 2736 *retp = 0;
2737 return ppp;
2738
2739out2:
273ec51d 2740 mutex_unlock(&pn->all_ppp_mutex);
1da177e4
LT		 2741 free_netdev(dev);
2742out1:
1da177e4
LT		 2743 *retp = ret;
2744 return NULL;
2745}
2746
2747/*
2748 * Initialize a ppp_file structure.
2749 */
2750static void
2751init_ppp_file(struct ppp_file *pf, int kind)
2752{
2753 pf->kind = kind;
2754 skb_queue_head_init(&pf->xq);
2755 skb_queue_head_init(&pf->rq);
2756 atomic_set(&pf->refcnt, 1);
2757 init_waitqueue_head(&pf->rwait);
2758}
2759
2760/*
2761 * Take down a ppp interface unit - called when the owning file
2762 * (the one that created the unit) is closed or detached.
2763 */
2764static void ppp_shutdown_interface(struct ppp *ppp)
2765{
273ec51d
CG		 2766 struct ppp_net *pn;
2767
2768 pn = ppp_pernet(ppp->ppp_net);
2769 mutex_lock(&pn->all_ppp_mutex);
2770
1da177e4 2771 /* This will call dev_close() for us. */
739840d5
JC		 2772 ppp_lock(ppp);
2773 if (!ppp->closing) {
2774 ppp->closing = 1;
2775 ppp_unlock(ppp);
2776 unregister_netdev(ppp->dev);
bcc70bb3 2777 unit_put(&pn->units_idr, ppp->file.index);
739840d5
JC		 2778 } else
2779 ppp_unlock(ppp);
2780
1da177e4
LT		 2781 ppp->file.dead = 1;
2782 ppp->owner = NULL;
2783 wake_up_interruptible(&ppp->file.rwait);
273ec51d
CG		 2784
2785 mutex_unlock(&pn->all_ppp_mutex);
1da177e4
LT		 2786}
2787
2788/*
2789 * Free the memory used by a ppp unit. This is only called once
2790 * there are no channels connected to the unit and no file structs
2791 * that reference the unit.
2792 */
2793static void ppp_destroy_interface(struct ppp *ppp)
2794{
2795 atomic_dec(&ppp_unit_count);
2796
2797 if (!ppp->file.dead || ppp->n_channels) {
2798 /* "can't happen" */
b48f8c23
DM		 2799 netdev_err(ppp->dev, "ppp: destroying ppp struct %p "
2800 "but dead=%d n_channels=%d !\n",
2801 ppp, ppp->file.dead, ppp->n_channels);
1da177e4
LT		 2802 return;
2803 }
2804
2805 ppp_ccp_closed(ppp);
2806 if (ppp->vj) {
2807 slhc_free(ppp->vj);
2808 ppp->vj = NULL;
2809 }
2810 skb_queue_purge(&ppp->file.xq);
2811 skb_queue_purge(&ppp->file.rq);
2812#ifdef CONFIG_PPP_MULTILINK
2813 skb_queue_purge(&ppp->mrq);
2814#endif /* CONFIG_PPP_MULTILINK */
2815#ifdef CONFIG_PPP_FILTER
568f194e
DB		 2816 if (ppp->pass_filter) {
2817 sk_unattached_filter_destroy(ppp->pass_filter);
2818 ppp->pass_filter = NULL;
2819 }
2820
2821 if (ppp->active_filter) {
2822 sk_unattached_filter_destroy(ppp->active_filter);
2823 ppp->active_filter = NULL;
2824 }
1da177e4
LT		 2825#endif /* CONFIG_PPP_FILTER */
2826
1d2f8c95 2827 kfree_skb(ppp->xmit_pending);
165de5b7 2828
739840d5 2829 free_netdev(ppp->dev);
1da177e4
LT		 2830}
2831
2832/*
2833 * Locate an existing ppp unit.
8ed965d6 2834 * The caller should have locked the all_ppp_mutex.
1da177e4
LT		 2835 */
2836static struct ppp *
273ec51d 2837ppp_find_unit(struct ppp_net *pn, int unit)
1da177e4 2838{
273ec51d 2839 return unit_find(&pn->units_idr, unit);
1da177e4
LT		 2840}
2841
2842/*
2843 * Locate an existing ppp channel.
2844 * The caller should have locked the all_channels_lock.
2845 * First we look in the new_channels list, then in the
2846 * all_channels list. If found in the new_channels list,
2847 * we move it to the all_channels list. This is for speed
2848 * when we have a lot of channels in use.
2849 */
2850static struct channel *
273ec51d 2851ppp_find_channel(struct ppp_net *pn, int unit)
1da177e4
LT		 2852{
2853 struct channel *pch;
1da177e4 2854
273ec51d 2855 list_for_each_entry(pch, &pn->new_channels, list) {
1da177e4 2856 if (pch->file.index == unit) {
273ec51d 2857 list_move(&pch->list, &pn->all_channels);
1da177e4
LT		 2858 return pch;
2859 }
2860 }
273ec51d
CG		 2861
2862 list_for_each_entry(pch, &pn->all_channels, list) {
1da177e4
LT		 2863 if (pch->file.index == unit)
2864 return pch;
2865 }
273ec51d 2866
1da177e4
LT		 2867 return NULL;
2868}
2869
2870/*
2871 * Connect a PPP channel to a PPP interface unit.
2872 */
2873static int
2874ppp_connect_channel(struct channel *pch, int unit)
2875{
2876 struct ppp *ppp;
273ec51d 2877 struct ppp_net *pn;
1da177e4
LT		 2878 int ret = -ENXIO;
2879 int hdrlen;
2880
273ec51d
CG		 2881 pn = ppp_pernet(pch->chan_net);
2882
2883 mutex_lock(&pn->all_ppp_mutex);
2884 ppp = ppp_find_unit(pn, unit);
cd228d54 2885 if (!ppp)
1da177e4
LT		 2886 goto out;
2887 write_lock_bh(&pch->upl);
2888 ret = -EINVAL;
cd228d54 2889 if (pch->ppp)
1da177e4
LT		 2890 goto outl;
2891
2892 ppp_lock(ppp);
2893 if (pch->file.hdrlen > ppp->file.hdrlen)
2894 ppp->file.hdrlen = pch->file.hdrlen;
2895 hdrlen = pch->file.hdrlen + 2; /* for protocol bytes */
739840d5 2896 if (hdrlen > ppp->dev->hard_header_len)
1da177e4
LT		 2897 ppp->dev->hard_header_len = hdrlen;
2898 list_add_tail(&pch->clist, &ppp->channels);
2899 ++ppp->n_channels;
2900 pch->ppp = ppp;
2901 atomic_inc(&ppp->file.refcnt);
2902 ppp_unlock(ppp);
2903 ret = 0;
2904
2905 outl:
2906 write_unlock_bh(&pch->upl);
2907 out:
273ec51d 2908 mutex_unlock(&pn->all_ppp_mutex);
1da177e4
LT		 2909 return ret;
2910}
2911
2912/*
2913 * Disconnect a channel from its ppp unit.
2914 */
2915static int
2916ppp_disconnect_channel(struct channel *pch)
2917{
2918 struct ppp *ppp;
2919 int err = -EINVAL;
2920
2921 write_lock_bh(&pch->upl);
2922 ppp = pch->ppp;
2923 pch->ppp = NULL;
2924 write_unlock_bh(&pch->upl);
cd228d54 2925 if (ppp) {
1da177e4
LT		 2926 /* remove it from the ppp unit's list */
2927 ppp_lock(ppp);
2928 list_del(&pch->clist);
2929 if (--ppp->n_channels == 0)
2930 wake_up_interruptible(&ppp->file.rwait);
2931 ppp_unlock(ppp);
2932 if (atomic_dec_and_test(&ppp->file.refcnt))
2933 ppp_destroy_interface(ppp);
2934 err = 0;
2935 }
2936 return err;
2937}
2938
2939/*
2940 * Free up the resources used by a ppp channel.
2941 */
2942static void ppp_destroy_channel(struct channel *pch)
2943{
2944 atomic_dec(&channel_count);
2945
2946 if (!pch->file.dead) {
2947 /* "can't happen" */
b48f8c23 2948 pr_err("ppp: destroying undead channel %p !\n", pch);
1da177e4
LT		 2949 return;
2950 }
2951 skb_queue_purge(&pch->file.xq);
2952 skb_queue_purge(&pch->file.rq);
2953 kfree(pch);
2954}
2955
2956static void __exit ppp_cleanup(void)
2957{
2958 /* should never happen */
2959 if (atomic_read(&ppp_unit_count) || atomic_read(&channel_count))
b48f8c23 2960 pr_err("PPP: removing module but units remain!\n");
68fc4fab 2961 unregister_chrdev(PPP_MAJOR, "ppp");
9a6a2a5e 2962 device_destroy(ppp_class, MKDEV(PPP_MAJOR, 0));
56b22935 2963 class_destroy(ppp_class);
741a6fa2 2964 unregister_pernet_device(&ppp_net_ops);
1da177e4
LT		 2965}
2966
2967/*
7a95d267
CG		 2968 * Units handling. Caller must protect concurrent access
2969 * by holding all_ppp_mutex
1da177e4 2970 */
7a95d267 2971
bcc70bb3
CG		 2972/* associate pointer with specified number */
2973static int unit_set(struct idr *p, void *ptr, int n)
2974{
2975 int unit;
85997576 2976
2fa532c5
TH		 2977 unit = idr_alloc(p, ptr, n, n + 1, GFP_KERNEL);
2978 if (unit == -ENOSPC)
2979 unit = -EINVAL;
85997576
CG		 2980 return unit;
2981}
2982
7a95d267
CG		 2983/* get new free unit number and associate pointer with it */
2984static int unit_get(struct idr *p, void *ptr)
1da177e4 2985{
2fa532c5 2986 return idr_alloc(p, ptr, 0, 0, GFP_KERNEL);
1da177e4
LT		 2987}
2988
7a95d267
CG		 2989/* put unit number back to a pool */
2990static void unit_put(struct idr *p, int n)
1da177e4 2991{
7a95d267 2992 idr_remove(p, n);
1da177e4
LT		 2993}
2994
7a95d267
CG		 2995/* get pointer associated with the number */
2996static void *unit_find(struct idr *p, int n)
1da177e4 2997{
7a95d267 2998 return idr_find(p, n);
1da177e4
LT		 2999}
3000
3001/* Module/initialization stuff */
3002
3003module_init(ppp_init);
3004module_exit(ppp_cleanup);
3005
273ec51d 3006EXPORT_SYMBOL(ppp_register_net_channel);
1da177e4
LT		 3007EXPORT_SYMBOL(ppp_register_channel);
3008EXPORT_SYMBOL(ppp_unregister_channel);
3009EXPORT_SYMBOL(ppp_channel_index);
3010EXPORT_SYMBOL(ppp_unit_number);
63f96072 3011EXPORT_SYMBOL(ppp_dev_name);
1da177e4
LT		 3012EXPORT_SYMBOL(ppp_input);
3013EXPORT_SYMBOL(ppp_input_error);
3014EXPORT_SYMBOL(ppp_output_wakeup);
3015EXPORT_SYMBOL(ppp_register_compressor);
3016EXPORT_SYMBOL(ppp_unregister_compressor);
3017MODULE_LICENSE("GPL");
578454ff
KS		 3018MODULE_ALIAS_CHARDEV(PPP_MAJOR, 0);
3019MODULE_ALIAS("devname:ppp");
Linux kernel - Deliverables
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