]>
Commit | Line | Data |
---|---|---|
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> | |
1da177e4 LT |
30 | #include <linux/netdevice.h> |
31 | #include <linux/poll.h> | |
32 | #include <linux/ppp_defs.h> | |
33 | #include <linux/filter.h> | |
34 | #include <linux/if_ppp.h> | |
35 | #include <linux/ppp_channel.h> | |
36 | #include <linux/ppp-comp.h> | |
37 | #include <linux/skbuff.h> | |
38 | #include <linux/rtnetlink.h> | |
39 | #include <linux/if_arp.h> | |
40 | #include <linux/ip.h> | |
41 | #include <linux/tcp.h> | |
f2b9857e | 42 | #include <linux/smp_lock.h> |
1da177e4 | 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> |
1da177e4 LT |
48 | #include <net/slhc_vj.h> |
49 | #include <asm/atomic.h> | |
50 | ||
51 | #define PPP_VERSION "2.4.2" | |
52 | ||
53 | /* | |
54 | * Network protocols we support. | |
55 | */ | |
56 | #define NP_IP 0 /* Internet Protocol V4 */ | |
57 | #define NP_IPV6 1 /* Internet Protocol V6 */ | |
58 | #define NP_IPX 2 /* IPX protocol */ | |
59 | #define NP_AT 3 /* Appletalk protocol */ | |
60 | #define NP_MPLS_UC 4 /* MPLS unicast */ | |
61 | #define NP_MPLS_MC 5 /* MPLS multicast */ | |
62 | #define NUM_NP 6 /* Number of NPs. */ | |
63 | ||
64 | #define MPHDRLEN 6 /* multilink protocol header length */ | |
65 | #define MPHDRLEN_SSN 4 /* ditto with short sequence numbers */ | |
66 | #define MIN_FRAG_SIZE 64 | |
67 | ||
68 | /* | |
69 | * An instance of /dev/ppp can be associated with either a ppp | |
70 | * interface unit or a ppp channel. In both cases, file->private_data | |
71 | * points to one of these. | |
72 | */ | |
73 | struct ppp_file { | |
74 | enum { | |
75 | INTERFACE=1, CHANNEL | |
76 | } kind; | |
77 | struct sk_buff_head xq; /* pppd transmit queue */ | |
78 | struct sk_buff_head rq; /* receive queue for pppd */ | |
79 | wait_queue_head_t rwait; /* for poll on reading /dev/ppp */ | |
80 | atomic_t refcnt; /* # refs (incl /dev/ppp attached) */ | |
81 | int hdrlen; /* space to leave for headers */ | |
82 | int index; /* interface unit / channel number */ | |
83 | int dead; /* unit/channel has been shut down */ | |
84 | }; | |
85 | ||
b385a144 | 86 | #define PF_TO_X(pf, X) container_of(pf, X, file) |
1da177e4 LT |
87 | |
88 | #define PF_TO_PPP(pf) PF_TO_X(pf, struct ppp) | |
89 | #define PF_TO_CHANNEL(pf) PF_TO_X(pf, struct channel) | |
90 | ||
1da177e4 LT |
91 | /* |
92 | * Data structure describing one ppp unit. | |
93 | * A ppp unit corresponds to a ppp network interface device | |
94 | * and represents a multilink bundle. | |
95 | * It can have 0 or more ppp channels connected to it. | |
96 | */ | |
97 | struct ppp { | |
98 | struct ppp_file file; /* stuff for read/write/poll 0 */ | |
99 | struct file *owner; /* file that owns this unit 48 */ | |
100 | struct list_head channels; /* list of attached channels 4c */ | |
101 | int n_channels; /* how many channels are attached 54 */ | |
102 | spinlock_t rlock; /* lock for receive side 58 */ | |
103 | spinlock_t wlock; /* lock for transmit side 5c */ | |
104 | int mru; /* max receive unit 60 */ | |
105 | unsigned int flags; /* control bits 64 */ | |
106 | unsigned int xstate; /* transmit state bits 68 */ | |
107 | unsigned int rstate; /* receive state bits 6c */ | |
108 | int debug; /* debug flags 70 */ | |
109 | struct slcompress *vj; /* state for VJ header compression */ | |
110 | enum NPmode npmode[NUM_NP]; /* what to do with each net proto 78 */ | |
111 | struct sk_buff *xmit_pending; /* a packet ready to go out 88 */ | |
112 | struct compressor *xcomp; /* transmit packet compressor 8c */ | |
113 | void *xc_state; /* its internal state 90 */ | |
114 | struct compressor *rcomp; /* receive decompressor 94 */ | |
115 | void *rc_state; /* its internal state 98 */ | |
116 | unsigned long last_xmit; /* jiffies when last pkt sent 9c */ | |
117 | unsigned long last_recv; /* jiffies when last pkt rcvd a0 */ | |
118 | struct net_device *dev; /* network interface device a4 */ | |
739840d5 | 119 | int closing; /* is device closing down? a8 */ |
1da177e4 LT |
120 | #ifdef CONFIG_PPP_MULTILINK |
121 | int nxchan; /* next channel to send something on */ | |
122 | u32 nxseq; /* next sequence number to send */ | |
123 | int mrru; /* MP: max reconst. receive unit */ | |
124 | u32 nextseq; /* MP: seq no of next packet */ | |
125 | u32 minseq; /* MP: min of most recent seqnos */ | |
126 | struct sk_buff_head mrq; /* MP: receive reconstruction queue */ | |
127 | #endif /* CONFIG_PPP_MULTILINK */ | |
1da177e4 LT |
128 | #ifdef CONFIG_PPP_FILTER |
129 | struct sock_filter *pass_filter; /* filter for packets to pass */ | |
130 | struct sock_filter *active_filter;/* filter for pkts to reset idle */ | |
131 | unsigned pass_len, active_len; | |
132 | #endif /* CONFIG_PPP_FILTER */ | |
133 | }; | |
134 | ||
135 | /* | |
136 | * Bits in flags: SC_NO_TCP_CCID, SC_CCP_OPEN, SC_CCP_UP, SC_LOOP_TRAFFIC, | |
b3f9b92a MD |
137 | * SC_MULTILINK, SC_MP_SHORTSEQ, SC_MP_XSHORTSEQ, SC_COMP_TCP, SC_REJ_COMP_TCP, |
138 | * SC_MUST_COMP | |
1da177e4 LT |
139 | * Bits in rstate: SC_DECOMP_RUN, SC_DC_ERROR, SC_DC_FERROR. |
140 | * Bits in xstate: SC_COMP_RUN | |
141 | */ | |
142 | #define SC_FLAG_BITS (SC_NO_TCP_CCID|SC_CCP_OPEN|SC_CCP_UP|SC_LOOP_TRAFFIC \ | |
143 | |SC_MULTILINK|SC_MP_SHORTSEQ|SC_MP_XSHORTSEQ \ | |
b3f9b92a | 144 | |SC_COMP_TCP|SC_REJ_COMP_TCP|SC_MUST_COMP) |
1da177e4 LT |
145 | |
146 | /* | |
147 | * Private data structure for each channel. | |
148 | * This includes the data structure used for multilink. | |
149 | */ | |
150 | struct channel { | |
151 | struct ppp_file file; /* stuff for read/write/poll */ | |
152 | struct list_head list; /* link in all/new_channels list */ | |
153 | struct ppp_channel *chan; /* public channel data structure */ | |
154 | struct rw_semaphore chan_sem; /* protects `chan' during chan ioctl */ | |
155 | spinlock_t downl; /* protects `chan', file.xq dequeue */ | |
156 | struct ppp *ppp; /* ppp unit we're connected to */ | |
157 | struct list_head clist; /* link in list of channels per unit */ | |
158 | rwlock_t upl; /* protects `ppp' */ | |
159 | #ifdef CONFIG_PPP_MULTILINK | |
160 | u8 avail; /* flag used in multilink stuff */ | |
161 | u8 had_frag; /* >= 1 fragments have been sent */ | |
162 | u32 lastseq; /* MP: last sequence # received */ | |
163 | #endif /* CONFIG_PPP_MULTILINK */ | |
164 | }; | |
165 | ||
166 | /* | |
167 | * SMP locking issues: | |
168 | * Both the ppp.rlock and ppp.wlock locks protect the ppp.channels | |
169 | * list and the ppp.n_channels field, you need to take both locks | |
170 | * before you modify them. | |
171 | * The lock ordering is: channel.upl -> ppp.wlock -> ppp.rlock -> | |
172 | * channel.downl. | |
173 | */ | |
174 | ||
175 | /* | |
176 | * A cardmap represents a mapping from unsigned integers to pointers, | |
177 | * and provides a fast "find lowest unused number" operation. | |
178 | * It uses a broad (32-way) tree with a bitmap at each level. | |
179 | * It is designed to be space-efficient for small numbers of entries | |
180 | * and time-efficient for large numbers of entries. | |
181 | */ | |
182 | #define CARDMAP_ORDER 5 | |
183 | #define CARDMAP_WIDTH (1U << CARDMAP_ORDER) | |
184 | #define CARDMAP_MASK (CARDMAP_WIDTH - 1) | |
185 | ||
186 | struct cardmap { | |
187 | int shift; | |
188 | unsigned long inuse; | |
189 | struct cardmap *parent; | |
190 | void *ptr[CARDMAP_WIDTH]; | |
191 | }; | |
192 | static void *cardmap_get(struct cardmap *map, unsigned int nr); | |
d4274b51 | 193 | static int cardmap_set(struct cardmap **map, unsigned int nr, void *ptr); |
1da177e4 LT |
194 | static unsigned int cardmap_find_first_free(struct cardmap *map); |
195 | static void cardmap_destroy(struct cardmap **map); | |
196 | ||
197 | /* | |
8ed965d6 | 198 | * all_ppp_mutex protects the all_ppp_units mapping. |
1da177e4 LT |
199 | * It also ensures that finding a ppp unit in the all_ppp_units map |
200 | * and updating its file.refcnt field is atomic. | |
201 | */ | |
8ed965d6 | 202 | static DEFINE_MUTEX(all_ppp_mutex); |
1da177e4 LT |
203 | static struct cardmap *all_ppp_units; |
204 | static atomic_t ppp_unit_count = ATOMIC_INIT(0); | |
205 | ||
206 | /* | |
207 | * all_channels_lock protects all_channels and last_channel_index, | |
208 | * and the atomicity of find a channel and updating its file.refcnt | |
209 | * field. | |
210 | */ | |
211 | static DEFINE_SPINLOCK(all_channels_lock); | |
212 | static LIST_HEAD(all_channels); | |
213 | static LIST_HEAD(new_channels); | |
214 | static int last_channel_index; | |
215 | static atomic_t channel_count = ATOMIC_INIT(0); | |
216 | ||
217 | /* Get the PPP protocol number from a skb */ | |
218 | #define PPP_PROTO(skb) (((skb)->data[0] << 8) + (skb)->data[1]) | |
219 | ||
220 | /* We limit the length of ppp->file.rq to this (arbitrary) value */ | |
221 | #define PPP_MAX_RQLEN 32 | |
222 | ||
223 | /* | |
224 | * Maximum number of multilink fragments queued up. | |
225 | * This has to be large enough to cope with the maximum latency of | |
226 | * the slowest channel relative to the others. Strictly it should | |
227 | * depend on the number of channels and their characteristics. | |
228 | */ | |
229 | #define PPP_MP_MAX_QLEN 128 | |
230 | ||
231 | /* Multilink header bits. */ | |
232 | #define B 0x80 /* this fragment begins a packet */ | |
233 | #define E 0x40 /* this fragment ends a packet */ | |
234 | ||
235 | /* Compare multilink sequence numbers (assumed to be 32 bits wide) */ | |
236 | #define seq_before(a, b) ((s32)((a) - (b)) < 0) | |
237 | #define seq_after(a, b) ((s32)((a) - (b)) > 0) | |
238 | ||
239 | /* Prototypes. */ | |
240 | static int ppp_unattached_ioctl(struct ppp_file *pf, struct file *file, | |
241 | unsigned int cmd, unsigned long arg); | |
242 | static void ppp_xmit_process(struct ppp *ppp); | |
243 | static void ppp_send_frame(struct ppp *ppp, struct sk_buff *skb); | |
244 | static void ppp_push(struct ppp *ppp); | |
245 | static void ppp_channel_push(struct channel *pch); | |
246 | static void ppp_receive_frame(struct ppp *ppp, struct sk_buff *skb, | |
247 | struct channel *pch); | |
248 | static void ppp_receive_error(struct ppp *ppp); | |
249 | static void ppp_receive_nonmp_frame(struct ppp *ppp, struct sk_buff *skb); | |
250 | static struct sk_buff *ppp_decompress_frame(struct ppp *ppp, | |
251 | struct sk_buff *skb); | |
252 | #ifdef CONFIG_PPP_MULTILINK | |
253 | static void ppp_receive_mp_frame(struct ppp *ppp, struct sk_buff *skb, | |
254 | struct channel *pch); | |
255 | static void ppp_mp_insert(struct ppp *ppp, struct sk_buff *skb); | |
256 | static struct sk_buff *ppp_mp_reconstruct(struct ppp *ppp); | |
257 | static int ppp_mp_explode(struct ppp *ppp, struct sk_buff *skb); | |
258 | #endif /* CONFIG_PPP_MULTILINK */ | |
259 | static int ppp_set_compress(struct ppp *ppp, unsigned long arg); | |
260 | static void ppp_ccp_peek(struct ppp *ppp, struct sk_buff *skb, int inbound); | |
261 | static void ppp_ccp_closed(struct ppp *ppp); | |
262 | static struct compressor *find_compressor(int type); | |
263 | static void ppp_get_stats(struct ppp *ppp, struct ppp_stats *st); | |
264 | static struct ppp *ppp_create_interface(int unit, int *retp); | |
265 | static void init_ppp_file(struct ppp_file *pf, int kind); | |
266 | static void ppp_shutdown_interface(struct ppp *ppp); | |
267 | static void ppp_destroy_interface(struct ppp *ppp); | |
268 | static struct ppp *ppp_find_unit(int unit); | |
269 | static struct channel *ppp_find_channel(int unit); | |
270 | static int ppp_connect_channel(struct channel *pch, int unit); | |
271 | static int ppp_disconnect_channel(struct channel *pch); | |
272 | static void ppp_destroy_channel(struct channel *pch); | |
273 | ||
56b22935 | 274 | static struct class *ppp_class; |
1da177e4 LT |
275 | |
276 | /* Translates a PPP protocol number to a NP index (NP == network protocol) */ | |
277 | static inline int proto_to_npindex(int proto) | |
278 | { | |
279 | switch (proto) { | |
280 | case PPP_IP: | |
281 | return NP_IP; | |
282 | case PPP_IPV6: | |
283 | return NP_IPV6; | |
284 | case PPP_IPX: | |
285 | return NP_IPX; | |
286 | case PPP_AT: | |
287 | return NP_AT; | |
288 | case PPP_MPLS_UC: | |
289 | return NP_MPLS_UC; | |
290 | case PPP_MPLS_MC: | |
291 | return NP_MPLS_MC; | |
292 | } | |
293 | return -EINVAL; | |
294 | } | |
295 | ||
296 | /* Translates an NP index into a PPP protocol number */ | |
297 | static const int npindex_to_proto[NUM_NP] = { | |
298 | PPP_IP, | |
299 | PPP_IPV6, | |
300 | PPP_IPX, | |
301 | PPP_AT, | |
302 | PPP_MPLS_UC, | |
303 | PPP_MPLS_MC, | |
304 | }; | |
6aa20a22 | 305 | |
1da177e4 LT |
306 | /* Translates an ethertype into an NP index */ |
307 | static inline int ethertype_to_npindex(int ethertype) | |
308 | { | |
309 | switch (ethertype) { | |
310 | case ETH_P_IP: | |
311 | return NP_IP; | |
312 | case ETH_P_IPV6: | |
313 | return NP_IPV6; | |
314 | case ETH_P_IPX: | |
315 | return NP_IPX; | |
316 | case ETH_P_PPPTALK: | |
317 | case ETH_P_ATALK: | |
318 | return NP_AT; | |
319 | case ETH_P_MPLS_UC: | |
320 | return NP_MPLS_UC; | |
321 | case ETH_P_MPLS_MC: | |
322 | return NP_MPLS_MC; | |
323 | } | |
324 | return -1; | |
325 | } | |
326 | ||
327 | /* Translates an NP index into an ethertype */ | |
328 | static const int npindex_to_ethertype[NUM_NP] = { | |
329 | ETH_P_IP, | |
330 | ETH_P_IPV6, | |
331 | ETH_P_IPX, | |
332 | ETH_P_PPPTALK, | |
333 | ETH_P_MPLS_UC, | |
334 | ETH_P_MPLS_MC, | |
335 | }; | |
336 | ||
337 | /* | |
338 | * Locking shorthand. | |
339 | */ | |
340 | #define ppp_xmit_lock(ppp) spin_lock_bh(&(ppp)->wlock) | |
341 | #define ppp_xmit_unlock(ppp) spin_unlock_bh(&(ppp)->wlock) | |
342 | #define ppp_recv_lock(ppp) spin_lock_bh(&(ppp)->rlock) | |
343 | #define ppp_recv_unlock(ppp) spin_unlock_bh(&(ppp)->rlock) | |
344 | #define ppp_lock(ppp) do { ppp_xmit_lock(ppp); \ | |
345 | ppp_recv_lock(ppp); } while (0) | |
346 | #define ppp_unlock(ppp) do { ppp_recv_unlock(ppp); \ | |
347 | ppp_xmit_unlock(ppp); } while (0) | |
348 | ||
349 | /* | |
350 | * /dev/ppp device routines. | |
351 | * The /dev/ppp device is used by pppd to control the ppp unit. | |
352 | * It supports the read, write, ioctl and poll functions. | |
353 | * Open instances of /dev/ppp can be in one of three states: | |
354 | * unattached, attached to a ppp unit, or attached to a ppp channel. | |
355 | */ | |
356 | static int ppp_open(struct inode *inode, struct file *file) | |
357 | { | |
f2b9857e | 358 | cycle_kernel_lock(); |
1da177e4 LT |
359 | /* |
360 | * This could (should?) be enforced by the permissions on /dev/ppp. | |
361 | */ | |
362 | if (!capable(CAP_NET_ADMIN)) | |
363 | return -EPERM; | |
364 | return 0; | |
365 | } | |
366 | ||
f3ff8a4d | 367 | static int ppp_release(struct inode *unused, struct file *file) |
1da177e4 LT |
368 | { |
369 | struct ppp_file *pf = file->private_data; | |
370 | struct ppp *ppp; | |
371 | ||
cd228d54 | 372 | if (pf) { |
1da177e4 LT |
373 | file->private_data = NULL; |
374 | if (pf->kind == INTERFACE) { | |
375 | ppp = PF_TO_PPP(pf); | |
376 | if (file == ppp->owner) | |
377 | ppp_shutdown_interface(ppp); | |
378 | } | |
379 | if (atomic_dec_and_test(&pf->refcnt)) { | |
380 | switch (pf->kind) { | |
381 | case INTERFACE: | |
382 | ppp_destroy_interface(PF_TO_PPP(pf)); | |
383 | break; | |
384 | case CHANNEL: | |
385 | ppp_destroy_channel(PF_TO_CHANNEL(pf)); | |
386 | break; | |
387 | } | |
388 | } | |
389 | } | |
390 | return 0; | |
391 | } | |
392 | ||
393 | static ssize_t ppp_read(struct file *file, char __user *buf, | |
394 | size_t count, loff_t *ppos) | |
395 | { | |
396 | struct ppp_file *pf = file->private_data; | |
397 | DECLARE_WAITQUEUE(wait, current); | |
398 | ssize_t ret; | |
399 | struct sk_buff *skb = NULL; | |
400 | ||
401 | ret = count; | |
402 | ||
cd228d54 | 403 | if (!pf) |
1da177e4 LT |
404 | return -ENXIO; |
405 | add_wait_queue(&pf->rwait, &wait); | |
406 | for (;;) { | |
407 | set_current_state(TASK_INTERRUPTIBLE); | |
408 | skb = skb_dequeue(&pf->rq); | |
409 | if (skb) | |
410 | break; | |
411 | ret = 0; | |
412 | if (pf->dead) | |
413 | break; | |
414 | if (pf->kind == INTERFACE) { | |
415 | /* | |
416 | * Return 0 (EOF) on an interface that has no | |
417 | * channels connected, unless it is looping | |
418 | * network traffic (demand mode). | |
419 | */ | |
420 | struct ppp *ppp = PF_TO_PPP(pf); | |
421 | if (ppp->n_channels == 0 | |
422 | && (ppp->flags & SC_LOOP_TRAFFIC) == 0) | |
423 | break; | |
424 | } | |
425 | ret = -EAGAIN; | |
426 | if (file->f_flags & O_NONBLOCK) | |
427 | break; | |
428 | ret = -ERESTARTSYS; | |
429 | if (signal_pending(current)) | |
430 | break; | |
431 | schedule(); | |
432 | } | |
433 | set_current_state(TASK_RUNNING); | |
434 | remove_wait_queue(&pf->rwait, &wait); | |
435 | ||
cd228d54 | 436 | if (!skb) |
1da177e4 LT |
437 | goto out; |
438 | ||
439 | ret = -EOVERFLOW; | |
440 | if (skb->len > count) | |
441 | goto outf; | |
442 | ret = -EFAULT; | |
443 | if (copy_to_user(buf, skb->data, skb->len)) | |
444 | goto outf; | |
445 | ret = skb->len; | |
446 | ||
447 | outf: | |
448 | kfree_skb(skb); | |
449 | out: | |
450 | return ret; | |
451 | } | |
452 | ||
453 | static ssize_t ppp_write(struct file *file, const char __user *buf, | |
454 | size_t count, loff_t *ppos) | |
455 | { | |
456 | struct ppp_file *pf = file->private_data; | |
457 | struct sk_buff *skb; | |
458 | ssize_t ret; | |
459 | ||
cd228d54 | 460 | if (!pf) |
1da177e4 LT |
461 | return -ENXIO; |
462 | ret = -ENOMEM; | |
463 | skb = alloc_skb(count + pf->hdrlen, GFP_KERNEL); | |
cd228d54 | 464 | if (!skb) |
1da177e4 LT |
465 | goto out; |
466 | skb_reserve(skb, pf->hdrlen); | |
467 | ret = -EFAULT; | |
468 | if (copy_from_user(skb_put(skb, count), buf, count)) { | |
469 | kfree_skb(skb); | |
470 | goto out; | |
471 | } | |
472 | ||
473 | skb_queue_tail(&pf->xq, skb); | |
474 | ||
475 | switch (pf->kind) { | |
476 | case INTERFACE: | |
477 | ppp_xmit_process(PF_TO_PPP(pf)); | |
478 | break; | |
479 | case CHANNEL: | |
480 | ppp_channel_push(PF_TO_CHANNEL(pf)); | |
481 | break; | |
482 | } | |
483 | ||
484 | ret = count; | |
485 | ||
486 | out: | |
487 | return ret; | |
488 | } | |
489 | ||
490 | /* No kernel lock - fine */ | |
491 | static unsigned int ppp_poll(struct file *file, poll_table *wait) | |
492 | { | |
493 | struct ppp_file *pf = file->private_data; | |
494 | unsigned int mask; | |
495 | ||
cd228d54 | 496 | if (!pf) |
1da177e4 LT |
497 | return 0; |
498 | poll_wait(file, &pf->rwait, wait); | |
499 | mask = POLLOUT | POLLWRNORM; | |
cd228d54 | 500 | if (skb_peek(&pf->rq)) |
1da177e4 LT |
501 | mask |= POLLIN | POLLRDNORM; |
502 | if (pf->dead) | |
503 | mask |= POLLHUP; | |
504 | else if (pf->kind == INTERFACE) { | |
505 | /* see comment in ppp_read */ | |
506 | struct ppp *ppp = PF_TO_PPP(pf); | |
507 | if (ppp->n_channels == 0 | |
508 | && (ppp->flags & SC_LOOP_TRAFFIC) == 0) | |
509 | mask |= POLLIN | POLLRDNORM; | |
510 | } | |
511 | ||
512 | return mask; | |
513 | } | |
514 | ||
515 | #ifdef CONFIG_PPP_FILTER | |
516 | static int get_filter(void __user *arg, struct sock_filter **p) | |
517 | { | |
518 | struct sock_fprog uprog; | |
519 | struct sock_filter *code = NULL; | |
520 | int len, err; | |
521 | ||
522 | if (copy_from_user(&uprog, arg, sizeof(uprog))) | |
523 | return -EFAULT; | |
524 | ||
1da177e4 LT |
525 | if (!uprog.len) { |
526 | *p = NULL; | |
527 | return 0; | |
528 | } | |
529 | ||
530 | len = uprog.len * sizeof(struct sock_filter); | |
531 | code = kmalloc(len, GFP_KERNEL); | |
532 | if (code == NULL) | |
533 | return -ENOMEM; | |
534 | ||
535 | if (copy_from_user(code, uprog.filter, len)) { | |
536 | kfree(code); | |
537 | return -EFAULT; | |
538 | } | |
539 | ||
540 | err = sk_chk_filter(code, uprog.len); | |
541 | if (err) { | |
542 | kfree(code); | |
543 | return err; | |
544 | } | |
545 | ||
546 | *p = code; | |
547 | return uprog.len; | |
548 | } | |
549 | #endif /* CONFIG_PPP_FILTER */ | |
550 | ||
f3ff8a4d | 551 | static long ppp_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
1da177e4 LT |
552 | { |
553 | struct ppp_file *pf = file->private_data; | |
554 | struct ppp *ppp; | |
555 | int err = -EFAULT, val, val2, i; | |
556 | struct ppp_idle idle; | |
557 | struct npioctl npi; | |
558 | int unit, cflags; | |
559 | struct slcompress *vj; | |
560 | void __user *argp = (void __user *)arg; | |
561 | int __user *p = argp; | |
562 | ||
cd228d54 | 563 | if (!pf) |
1da177e4 LT |
564 | return ppp_unattached_ioctl(pf, file, cmd, arg); |
565 | ||
566 | if (cmd == PPPIOCDETACH) { | |
567 | /* | |
568 | * We have to be careful here... if the file descriptor | |
569 | * has been dup'd, we could have another process in the | |
570 | * middle of a poll using the same file *, so we had | |
571 | * better not free the interface data structures - | |
572 | * instead we fail the ioctl. Even in this case, we | |
573 | * shut down the interface if we are the owner of it. | |
574 | * Actually, we should get rid of PPPIOCDETACH, userland | |
575 | * (i.e. pppd) could achieve the same effect by closing | |
576 | * this fd and reopening /dev/ppp. | |
577 | */ | |
578 | err = -EINVAL; | |
f3ff8a4d | 579 | lock_kernel(); |
1da177e4 LT |
580 | if (pf->kind == INTERFACE) { |
581 | ppp = PF_TO_PPP(pf); | |
582 | if (file == ppp->owner) | |
583 | ppp_shutdown_interface(ppp); | |
584 | } | |
516e0cc5 | 585 | if (atomic_long_read(&file->f_count) <= 2) { |
f3ff8a4d | 586 | ppp_release(NULL, file); |
1da177e4 LT |
587 | err = 0; |
588 | } else | |
516e0cc5 AV |
589 | printk(KERN_DEBUG "PPPIOCDETACH file->f_count=%ld\n", |
590 | atomic_long_read(&file->f_count)); | |
f3ff8a4d | 591 | unlock_kernel(); |
1da177e4 LT |
592 | return err; |
593 | } | |
594 | ||
595 | if (pf->kind == CHANNEL) { | |
f3ff8a4d | 596 | struct channel *pch; |
1da177e4 LT |
597 | struct ppp_channel *chan; |
598 | ||
f3ff8a4d AC |
599 | lock_kernel(); |
600 | pch = PF_TO_CHANNEL(pf); | |
601 | ||
1da177e4 LT |
602 | switch (cmd) { |
603 | case PPPIOCCONNECT: | |
604 | if (get_user(unit, p)) | |
605 | break; | |
606 | err = ppp_connect_channel(pch, unit); | |
607 | break; | |
608 | ||
609 | case PPPIOCDISCONN: | |
610 | err = ppp_disconnect_channel(pch); | |
611 | break; | |
612 | ||
613 | default: | |
614 | down_read(&pch->chan_sem); | |
615 | chan = pch->chan; | |
616 | err = -ENOTTY; | |
617 | if (chan && chan->ops->ioctl) | |
618 | err = chan->ops->ioctl(chan, cmd, arg); | |
619 | up_read(&pch->chan_sem); | |
620 | } | |
f3ff8a4d | 621 | unlock_kernel(); |
1da177e4 LT |
622 | return err; |
623 | } | |
624 | ||
625 | if (pf->kind != INTERFACE) { | |
626 | /* can't happen */ | |
627 | printk(KERN_ERR "PPP: not interface or channel??\n"); | |
628 | return -EINVAL; | |
629 | } | |
630 | ||
f3ff8a4d | 631 | lock_kernel(); |
1da177e4 LT |
632 | ppp = PF_TO_PPP(pf); |
633 | switch (cmd) { | |
634 | case PPPIOCSMRU: | |
635 | if (get_user(val, p)) | |
636 | break; | |
637 | ppp->mru = val; | |
638 | err = 0; | |
639 | break; | |
640 | ||
641 | case PPPIOCSFLAGS: | |
642 | if (get_user(val, p)) | |
643 | break; | |
644 | ppp_lock(ppp); | |
645 | cflags = ppp->flags & ~val; | |
646 | ppp->flags = val & SC_FLAG_BITS; | |
647 | ppp_unlock(ppp); | |
648 | if (cflags & SC_CCP_OPEN) | |
649 | ppp_ccp_closed(ppp); | |
650 | err = 0; | |
651 | break; | |
652 | ||
653 | case PPPIOCGFLAGS: | |
654 | val = ppp->flags | ppp->xstate | ppp->rstate; | |
655 | if (put_user(val, p)) | |
656 | break; | |
657 | err = 0; | |
658 | break; | |
659 | ||
660 | case PPPIOCSCOMPRESS: | |
661 | err = ppp_set_compress(ppp, arg); | |
662 | break; | |
663 | ||
664 | case PPPIOCGUNIT: | |
665 | if (put_user(ppp->file.index, p)) | |
666 | break; | |
667 | err = 0; | |
668 | break; | |
669 | ||
670 | case PPPIOCSDEBUG: | |
671 | if (get_user(val, p)) | |
672 | break; | |
673 | ppp->debug = val; | |
674 | err = 0; | |
675 | break; | |
676 | ||
677 | case PPPIOCGDEBUG: | |
678 | if (put_user(ppp->debug, p)) | |
679 | break; | |
680 | err = 0; | |
681 | break; | |
682 | ||
683 | case PPPIOCGIDLE: | |
684 | idle.xmit_idle = (jiffies - ppp->last_xmit) / HZ; | |
685 | idle.recv_idle = (jiffies - ppp->last_recv) / HZ; | |
686 | if (copy_to_user(argp, &idle, sizeof(idle))) | |
687 | break; | |
688 | err = 0; | |
689 | break; | |
690 | ||
691 | case PPPIOCSMAXCID: | |
692 | if (get_user(val, p)) | |
693 | break; | |
694 | val2 = 15; | |
695 | if ((val >> 16) != 0) { | |
696 | val2 = val >> 16; | |
697 | val &= 0xffff; | |
698 | } | |
699 | vj = slhc_init(val2+1, val+1); | |
cd228d54 | 700 | if (!vj) { |
1da177e4 LT |
701 | printk(KERN_ERR "PPP: no memory (VJ compressor)\n"); |
702 | err = -ENOMEM; | |
703 | break; | |
704 | } | |
705 | ppp_lock(ppp); | |
cd228d54 | 706 | if (ppp->vj) |
1da177e4 LT |
707 | slhc_free(ppp->vj); |
708 | ppp->vj = vj; | |
709 | ppp_unlock(ppp); | |
710 | err = 0; | |
711 | break; | |
712 | ||
713 | case PPPIOCGNPMODE: | |
714 | case PPPIOCSNPMODE: | |
715 | if (copy_from_user(&npi, argp, sizeof(npi))) | |
716 | break; | |
717 | err = proto_to_npindex(npi.protocol); | |
718 | if (err < 0) | |
719 | break; | |
720 | i = err; | |
721 | if (cmd == PPPIOCGNPMODE) { | |
722 | err = -EFAULT; | |
723 | npi.mode = ppp->npmode[i]; | |
724 | if (copy_to_user(argp, &npi, sizeof(npi))) | |
725 | break; | |
726 | } else { | |
727 | ppp->npmode[i] = npi.mode; | |
728 | /* we may be able to transmit more packets now (??) */ | |
729 | netif_wake_queue(ppp->dev); | |
730 | } | |
731 | err = 0; | |
732 | break; | |
733 | ||
734 | #ifdef CONFIG_PPP_FILTER | |
735 | case PPPIOCSPASS: | |
736 | { | |
737 | struct sock_filter *code; | |
738 | err = get_filter(argp, &code); | |
739 | if (err >= 0) { | |
740 | ppp_lock(ppp); | |
741 | kfree(ppp->pass_filter); | |
742 | ppp->pass_filter = code; | |
743 | ppp->pass_len = err; | |
744 | ppp_unlock(ppp); | |
745 | err = 0; | |
746 | } | |
747 | break; | |
748 | } | |
749 | case PPPIOCSACTIVE: | |
750 | { | |
751 | struct sock_filter *code; | |
752 | err = get_filter(argp, &code); | |
753 | if (err >= 0) { | |
754 | ppp_lock(ppp); | |
755 | kfree(ppp->active_filter); | |
756 | ppp->active_filter = code; | |
757 | ppp->active_len = err; | |
758 | ppp_unlock(ppp); | |
759 | err = 0; | |
760 | } | |
761 | break; | |
762 | } | |
763 | #endif /* CONFIG_PPP_FILTER */ | |
764 | ||
765 | #ifdef CONFIG_PPP_MULTILINK | |
766 | case PPPIOCSMRRU: | |
767 | if (get_user(val, p)) | |
768 | break; | |
769 | ppp_recv_lock(ppp); | |
770 | ppp->mrru = val; | |
771 | ppp_recv_unlock(ppp); | |
772 | err = 0; | |
773 | break; | |
774 | #endif /* CONFIG_PPP_MULTILINK */ | |
775 | ||
776 | default: | |
777 | err = -ENOTTY; | |
778 | } | |
f3ff8a4d | 779 | unlock_kernel(); |
1da177e4 LT |
780 | return err; |
781 | } | |
782 | ||
783 | static int ppp_unattached_ioctl(struct ppp_file *pf, struct file *file, | |
784 | unsigned int cmd, unsigned long arg) | |
785 | { | |
786 | int unit, err = -EFAULT; | |
787 | struct ppp *ppp; | |
788 | struct channel *chan; | |
789 | int __user *p = (int __user *)arg; | |
790 | ||
f3ff8a4d | 791 | lock_kernel(); |
1da177e4 LT |
792 | switch (cmd) { |
793 | case PPPIOCNEWUNIT: | |
794 | /* Create a new ppp unit */ | |
795 | if (get_user(unit, p)) | |
796 | break; | |
797 | ppp = ppp_create_interface(unit, &err); | |
cd228d54 | 798 | if (!ppp) |
1da177e4 LT |
799 | break; |
800 | file->private_data = &ppp->file; | |
801 | ppp->owner = file; | |
802 | err = -EFAULT; | |
803 | if (put_user(ppp->file.index, p)) | |
804 | break; | |
805 | err = 0; | |
806 | break; | |
807 | ||
808 | case PPPIOCATTACH: | |
809 | /* Attach to an existing ppp unit */ | |
810 | if (get_user(unit, p)) | |
811 | break; | |
8ed965d6 | 812 | mutex_lock(&all_ppp_mutex); |
1da177e4 LT |
813 | err = -ENXIO; |
814 | ppp = ppp_find_unit(unit); | |
cd228d54 | 815 | if (ppp) { |
1da177e4 LT |
816 | atomic_inc(&ppp->file.refcnt); |
817 | file->private_data = &ppp->file; | |
818 | err = 0; | |
819 | } | |
8ed965d6 | 820 | mutex_unlock(&all_ppp_mutex); |
1da177e4 LT |
821 | break; |
822 | ||
823 | case PPPIOCATTCHAN: | |
824 | if (get_user(unit, p)) | |
825 | break; | |
826 | spin_lock_bh(&all_channels_lock); | |
827 | err = -ENXIO; | |
828 | chan = ppp_find_channel(unit); | |
cd228d54 | 829 | if (chan) { |
1da177e4 LT |
830 | atomic_inc(&chan->file.refcnt); |
831 | file->private_data = &chan->file; | |
832 | err = 0; | |
833 | } | |
834 | spin_unlock_bh(&all_channels_lock); | |
835 | break; | |
836 | ||
837 | default: | |
838 | err = -ENOTTY; | |
839 | } | |
f3ff8a4d | 840 | unlock_kernel(); |
1da177e4 LT |
841 | return err; |
842 | } | |
843 | ||
d54b1fdb | 844 | static const struct file_operations ppp_device_fops = { |
1da177e4 LT |
845 | .owner = THIS_MODULE, |
846 | .read = ppp_read, | |
847 | .write = ppp_write, | |
848 | .poll = ppp_poll, | |
f3ff8a4d | 849 | .unlocked_ioctl = ppp_ioctl, |
1da177e4 LT |
850 | .open = ppp_open, |
851 | .release = ppp_release | |
852 | }; | |
853 | ||
854 | #define PPP_MAJOR 108 | |
855 | ||
856 | /* Called at boot time if ppp is compiled into the kernel, | |
857 | or at module load time (from init_module) if compiled as a module. */ | |
858 | static int __init ppp_init(void) | |
859 | { | |
860 | int err; | |
861 | ||
862 | printk(KERN_INFO "PPP generic driver version " PPP_VERSION "\n"); | |
863 | err = register_chrdev(PPP_MAJOR, "ppp", &ppp_device_fops); | |
864 | if (!err) { | |
56b22935 | 865 | ppp_class = class_create(THIS_MODULE, "ppp"); |
1da177e4 LT |
866 | if (IS_ERR(ppp_class)) { |
867 | err = PTR_ERR(ppp_class); | |
868 | goto out_chrdev; | |
869 | } | |
6e05d6c4 GKH |
870 | device_create(ppp_class, NULL, MKDEV(PPP_MAJOR, 0), NULL, |
871 | "ppp"); | |
1da177e4 LT |
872 | } |
873 | ||
874 | out: | |
875 | if (err) | |
876 | printk(KERN_ERR "failed to register PPP device (%d)\n", err); | |
877 | return err; | |
878 | ||
1da177e4 LT |
879 | out_chrdev: |
880 | unregister_chrdev(PPP_MAJOR, "ppp"); | |
881 | goto out; | |
882 | } | |
883 | ||
884 | /* | |
885 | * Network interface unit routines. | |
886 | */ | |
887 | static int | |
888 | ppp_start_xmit(struct sk_buff *skb, struct net_device *dev) | |
889 | { | |
890 | struct ppp *ppp = (struct ppp *) dev->priv; | |
891 | int npi, proto; | |
892 | unsigned char *pp; | |
893 | ||
894 | npi = ethertype_to_npindex(ntohs(skb->protocol)); | |
895 | if (npi < 0) | |
896 | goto outf; | |
897 | ||
898 | /* Drop, accept or reject the packet */ | |
899 | switch (ppp->npmode[npi]) { | |
900 | case NPMODE_PASS: | |
901 | break; | |
902 | case NPMODE_QUEUE: | |
903 | /* it would be nice to have a way to tell the network | |
904 | system to queue this one up for later. */ | |
905 | goto outf; | |
906 | case NPMODE_DROP: | |
907 | case NPMODE_ERROR: | |
908 | goto outf; | |
909 | } | |
910 | ||
911 | /* Put the 2-byte PPP protocol number on the front, | |
912 | making sure there is room for the address and control fields. */ | |
7b797d5b HX |
913 | if (skb_cow_head(skb, PPP_HDRLEN)) |
914 | goto outf; | |
915 | ||
1da177e4 LT |
916 | pp = skb_push(skb, 2); |
917 | proto = npindex_to_proto[npi]; | |
918 | pp[0] = proto >> 8; | |
919 | pp[1] = proto; | |
920 | ||
921 | netif_stop_queue(dev); | |
922 | skb_queue_tail(&ppp->file.xq, skb); | |
923 | ppp_xmit_process(ppp); | |
924 | return 0; | |
925 | ||
926 | outf: | |
927 | kfree_skb(skb); | |
8c0469cd | 928 | ++ppp->dev->stats.tx_dropped; |
1da177e4 LT |
929 | return 0; |
930 | } | |
931 | ||
1da177e4 LT |
932 | static int |
933 | ppp_net_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) | |
934 | { | |
935 | struct ppp *ppp = dev->priv; | |
936 | int err = -EFAULT; | |
937 | void __user *addr = (void __user *) ifr->ifr_ifru.ifru_data; | |
938 | struct ppp_stats stats; | |
939 | struct ppp_comp_stats cstats; | |
940 | char *vers; | |
941 | ||
942 | switch (cmd) { | |
943 | case SIOCGPPPSTATS: | |
944 | ppp_get_stats(ppp, &stats); | |
945 | if (copy_to_user(addr, &stats, sizeof(stats))) | |
946 | break; | |
947 | err = 0; | |
948 | break; | |
949 | ||
950 | case SIOCGPPPCSTATS: | |
951 | memset(&cstats, 0, sizeof(cstats)); | |
cd228d54 | 952 | if (ppp->xc_state) |
1da177e4 | 953 | ppp->xcomp->comp_stat(ppp->xc_state, &cstats.c); |
cd228d54 | 954 | if (ppp->rc_state) |
1da177e4 LT |
955 | ppp->rcomp->decomp_stat(ppp->rc_state, &cstats.d); |
956 | if (copy_to_user(addr, &cstats, sizeof(cstats))) | |
957 | break; | |
958 | err = 0; | |
959 | break; | |
960 | ||
961 | case SIOCGPPPVER: | |
962 | vers = PPP_VERSION; | |
963 | if (copy_to_user(addr, vers, strlen(vers) + 1)) | |
964 | break; | |
965 | err = 0; | |
966 | break; | |
967 | ||
968 | default: | |
969 | err = -EINVAL; | |
970 | } | |
971 | ||
972 | return err; | |
973 | } | |
974 | ||
975 | static void ppp_setup(struct net_device *dev) | |
976 | { | |
977 | dev->hard_header_len = PPP_HDRLEN; | |
978 | dev->mtu = PPP_MTU; | |
979 | dev->addr_len = 0; | |
980 | dev->tx_queue_len = 3; | |
981 | dev->type = ARPHRD_PPP; | |
982 | dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST; | |
983 | } | |
984 | ||
985 | /* | |
986 | * Transmit-side routines. | |
987 | */ | |
988 | ||
989 | /* | |
990 | * Called to do any work queued up on the transmit side | |
991 | * that can now be done. | |
992 | */ | |
993 | static void | |
994 | ppp_xmit_process(struct ppp *ppp) | |
995 | { | |
996 | struct sk_buff *skb; | |
997 | ||
998 | ppp_xmit_lock(ppp); | |
739840d5 | 999 | if (!ppp->closing) { |
1da177e4 | 1000 | ppp_push(ppp); |
cd228d54 JP |
1001 | while (!ppp->xmit_pending |
1002 | && (skb = skb_dequeue(&ppp->file.xq))) | |
1da177e4 LT |
1003 | ppp_send_frame(ppp, skb); |
1004 | /* If there's no work left to do, tell the core net | |
1005 | code that we can accept some more. */ | |
cd228d54 | 1006 | if (!ppp->xmit_pending && !skb_peek(&ppp->file.xq)) |
1da177e4 LT |
1007 | netif_wake_queue(ppp->dev); |
1008 | } | |
1009 | ppp_xmit_unlock(ppp); | |
1010 | } | |
1011 | ||
b3f9b92a MD |
1012 | static inline struct sk_buff * |
1013 | pad_compress_skb(struct ppp *ppp, struct sk_buff *skb) | |
1014 | { | |
1015 | struct sk_buff *new_skb; | |
1016 | int len; | |
1017 | int new_skb_size = ppp->dev->mtu + | |
1018 | ppp->xcomp->comp_extra + ppp->dev->hard_header_len; | |
1019 | int compressor_skb_size = ppp->dev->mtu + | |
1020 | ppp->xcomp->comp_extra + PPP_HDRLEN; | |
1021 | new_skb = alloc_skb(new_skb_size, GFP_ATOMIC); | |
1022 | if (!new_skb) { | |
1023 | if (net_ratelimit()) | |
1024 | printk(KERN_ERR "PPP: no memory (comp pkt)\n"); | |
1025 | return NULL; | |
1026 | } | |
1027 | if (ppp->dev->hard_header_len > PPP_HDRLEN) | |
1028 | skb_reserve(new_skb, | |
1029 | ppp->dev->hard_header_len - PPP_HDRLEN); | |
1030 | ||
1031 | /* compressor still expects A/C bytes in hdr */ | |
1032 | len = ppp->xcomp->compress(ppp->xc_state, skb->data - 2, | |
1033 | new_skb->data, skb->len + 2, | |
1034 | compressor_skb_size); | |
1035 | if (len > 0 && (ppp->flags & SC_CCP_UP)) { | |
1036 | kfree_skb(skb); | |
1037 | skb = new_skb; | |
1038 | skb_put(skb, len); | |
1039 | skb_pull(skb, 2); /* pull off A/C bytes */ | |
1040 | } else if (len == 0) { | |
1041 | /* didn't compress, or CCP not up yet */ | |
1042 | kfree_skb(new_skb); | |
1043 | new_skb = skb; | |
1044 | } else { | |
1045 | /* | |
1046 | * (len < 0) | |
1047 | * MPPE requires that we do not send unencrypted | |
1048 | * frames. The compressor will return -1 if we | |
1049 | * should drop the frame. We cannot simply test | |
1050 | * the compress_proto because MPPE and MPPC share | |
1051 | * the same number. | |
1052 | */ | |
1053 | if (net_ratelimit()) | |
1054 | printk(KERN_ERR "ppp: compressor dropped pkt\n"); | |
1055 | kfree_skb(skb); | |
1056 | kfree_skb(new_skb); | |
1057 | new_skb = NULL; | |
1058 | } | |
1059 | return new_skb; | |
1060 | } | |
1061 | ||
1da177e4 LT |
1062 | /* |
1063 | * Compress and send a frame. | |
1064 | * The caller should have locked the xmit path, | |
1065 | * and xmit_pending should be 0. | |
1066 | */ | |
1067 | static void | |
1068 | ppp_send_frame(struct ppp *ppp, struct sk_buff *skb) | |
1069 | { | |
1070 | int proto = PPP_PROTO(skb); | |
1071 | struct sk_buff *new_skb; | |
1072 | int len; | |
1073 | unsigned char *cp; | |
1074 | ||
1075 | if (proto < 0x8000) { | |
1076 | #ifdef CONFIG_PPP_FILTER | |
1077 | /* check if we should pass this packet */ | |
1078 | /* the filter instructions are constructed assuming | |
1079 | a four-byte PPP header on each packet */ | |
1080 | *skb_push(skb, 2) = 1; | |
1081 | if (ppp->pass_filter | |
1082 | && sk_run_filter(skb, ppp->pass_filter, | |
1083 | ppp->pass_len) == 0) { | |
1084 | if (ppp->debug & 1) | |
1085 | printk(KERN_DEBUG "PPP: outbound frame not passed\n"); | |
1086 | kfree_skb(skb); | |
1087 | return; | |
1088 | } | |
1089 | /* if this packet passes the active filter, record the time */ | |
1090 | if (!(ppp->active_filter | |
1091 | && sk_run_filter(skb, ppp->active_filter, | |
1092 | ppp->active_len) == 0)) | |
1093 | ppp->last_xmit = jiffies; | |
1094 | skb_pull(skb, 2); | |
1095 | #else | |
1096 | /* for data packets, record the time */ | |
1097 | ppp->last_xmit = jiffies; | |
1098 | #endif /* CONFIG_PPP_FILTER */ | |
1099 | } | |
1100 | ||
8c0469cd PZ |
1101 | ++ppp->dev->stats.tx_packets; |
1102 | ppp->dev->stats.tx_bytes += skb->len - 2; | |
1da177e4 LT |
1103 | |
1104 | switch (proto) { | |
1105 | case PPP_IP: | |
cd228d54 | 1106 | if (!ppp->vj || (ppp->flags & SC_COMP_TCP) == 0) |
1da177e4 LT |
1107 | break; |
1108 | /* try to do VJ TCP header compression */ | |
1109 | new_skb = alloc_skb(skb->len + ppp->dev->hard_header_len - 2, | |
1110 | GFP_ATOMIC); | |
cd228d54 | 1111 | if (!new_skb) { |
1da177e4 LT |
1112 | printk(KERN_ERR "PPP: no memory (VJ comp pkt)\n"); |
1113 | goto drop; | |
1114 | } | |
1115 | skb_reserve(new_skb, ppp->dev->hard_header_len - 2); | |
1116 | cp = skb->data + 2; | |
1117 | len = slhc_compress(ppp->vj, cp, skb->len - 2, | |
1118 | new_skb->data + 2, &cp, | |
1119 | !(ppp->flags & SC_NO_TCP_CCID)); | |
1120 | if (cp == skb->data + 2) { | |
1121 | /* didn't compress */ | |
1122 | kfree_skb(new_skb); | |
1123 | } else { | |
1124 | if (cp[0] & SL_TYPE_COMPRESSED_TCP) { | |
1125 | proto = PPP_VJC_COMP; | |
1126 | cp[0] &= ~SL_TYPE_COMPRESSED_TCP; | |
1127 | } else { | |
1128 | proto = PPP_VJC_UNCOMP; | |
1129 | cp[0] = skb->data[2]; | |
1130 | } | |
1131 | kfree_skb(skb); | |
1132 | skb = new_skb; | |
1133 | cp = skb_put(skb, len + 2); | |
1134 | cp[0] = 0; | |
1135 | cp[1] = proto; | |
1136 | } | |
1137 | break; | |
1138 | ||
1139 | case PPP_CCP: | |
1140 | /* peek at outbound CCP frames */ | |
1141 | ppp_ccp_peek(ppp, skb, 0); | |
1142 | break; | |
1143 | } | |
1144 | ||
1145 | /* try to do packet compression */ | |
cd228d54 | 1146 | if ((ppp->xstate & SC_COMP_RUN) && ppp->xc_state |
1da177e4 | 1147 | && proto != PPP_LCP && proto != PPP_CCP) { |
b3f9b92a MD |
1148 | if (!(ppp->flags & SC_CCP_UP) && (ppp->flags & SC_MUST_COMP)) { |
1149 | if (net_ratelimit()) | |
1150 | printk(KERN_ERR "ppp: compression required but down - pkt dropped.\n"); | |
1da177e4 LT |
1151 | goto drop; |
1152 | } | |
b3f9b92a MD |
1153 | skb = pad_compress_skb(ppp, skb); |
1154 | if (!skb) | |
1155 | goto drop; | |
1da177e4 LT |
1156 | } |
1157 | ||
1158 | /* | |
1159 | * If we are waiting for traffic (demand dialling), | |
1160 | * queue it up for pppd to receive. | |
1161 | */ | |
1162 | if (ppp->flags & SC_LOOP_TRAFFIC) { | |
1163 | if (ppp->file.rq.qlen > PPP_MAX_RQLEN) | |
1164 | goto drop; | |
1165 | skb_queue_tail(&ppp->file.rq, skb); | |
1166 | wake_up_interruptible(&ppp->file.rwait); | |
1167 | return; | |
1168 | } | |
1169 | ||
1170 | ppp->xmit_pending = skb; | |
1171 | ppp_push(ppp); | |
1172 | return; | |
1173 | ||
1174 | drop: | |
b3f9b92a MD |
1175 | if (skb) |
1176 | kfree_skb(skb); | |
8c0469cd | 1177 | ++ppp->dev->stats.tx_errors; |
1da177e4 LT |
1178 | } |
1179 | ||
1180 | /* | |
1181 | * Try to send the frame in xmit_pending. | |
1182 | * The caller should have the xmit path locked. | |
1183 | */ | |
1184 | static void | |
1185 | ppp_push(struct ppp *ppp) | |
1186 | { | |
1187 | struct list_head *list; | |
1188 | struct channel *pch; | |
1189 | struct sk_buff *skb = ppp->xmit_pending; | |
1190 | ||
cd228d54 | 1191 | if (!skb) |
1da177e4 LT |
1192 | return; |
1193 | ||
1194 | list = &ppp->channels; | |
1195 | if (list_empty(list)) { | |
1196 | /* nowhere to send the packet, just drop it */ | |
1197 | ppp->xmit_pending = NULL; | |
1198 | kfree_skb(skb); | |
1199 | return; | |
1200 | } | |
1201 | ||
1202 | if ((ppp->flags & SC_MULTILINK) == 0) { | |
1203 | /* not doing multilink: send it down the first channel */ | |
1204 | list = list->next; | |
1205 | pch = list_entry(list, struct channel, clist); | |
1206 | ||
1207 | spin_lock_bh(&pch->downl); | |
1208 | if (pch->chan) { | |
1209 | if (pch->chan->ops->start_xmit(pch->chan, skb)) | |
1210 | ppp->xmit_pending = NULL; | |
1211 | } else { | |
1212 | /* channel got unregistered */ | |
1213 | kfree_skb(skb); | |
1214 | ppp->xmit_pending = NULL; | |
1215 | } | |
1216 | spin_unlock_bh(&pch->downl); | |
1217 | return; | |
1218 | } | |
1219 | ||
1220 | #ifdef CONFIG_PPP_MULTILINK | |
1221 | /* Multilink: fragment the packet over as many links | |
1222 | as can take the packet at the moment. */ | |
1223 | if (!ppp_mp_explode(ppp, skb)) | |
1224 | return; | |
1225 | #endif /* CONFIG_PPP_MULTILINK */ | |
1226 | ||
1227 | ppp->xmit_pending = NULL; | |
1228 | kfree_skb(skb); | |
1229 | } | |
1230 | ||
1231 | #ifdef CONFIG_PPP_MULTILINK | |
1232 | /* | |
1233 | * Divide a packet to be transmitted into fragments and | |
1234 | * send them out the individual links. | |
1235 | */ | |
1236 | static int ppp_mp_explode(struct ppp *ppp, struct sk_buff *skb) | |
1237 | { | |
516cd15f | 1238 | int len, fragsize; |
1da177e4 | 1239 | int i, bits, hdrlen, mtu; |
516cd15f PM |
1240 | int flen; |
1241 | int navail, nfree; | |
1242 | int nbigger; | |
1da177e4 LT |
1243 | unsigned char *p, *q; |
1244 | struct list_head *list; | |
1245 | struct channel *pch; | |
1246 | struct sk_buff *frag; | |
1247 | struct ppp_channel *chan; | |
1248 | ||
516cd15f PM |
1249 | nfree = 0; /* # channels which have no packet already queued */ |
1250 | navail = 0; /* total # of usable channels (not deregistered) */ | |
1da177e4 | 1251 | hdrlen = (ppp->flags & SC_MP_XSHORTSEQ)? MPHDRLEN_SSN: MPHDRLEN; |
516cd15f | 1252 | i = 0; |
81616c5a | 1253 | list_for_each_entry(pch, &ppp->channels, clist) { |
516cd15f PM |
1254 | navail += pch->avail = (pch->chan != NULL); |
1255 | if (pch->avail) { | |
b03efcfb DM |
1256 | if (skb_queue_empty(&pch->file.xq) || |
1257 | !pch->had_frag) { | |
516cd15f PM |
1258 | pch->avail = 2; |
1259 | ++nfree; | |
1da177e4 | 1260 | } |
516cd15f PM |
1261 | if (!pch->had_frag && i < ppp->nxchan) |
1262 | ppp->nxchan = i; | |
1da177e4 | 1263 | } |
516cd15f | 1264 | ++i; |
1da177e4 | 1265 | } |
516cd15f PM |
1266 | |
1267 | /* | |
1268 | * Don't start sending this packet unless at least half of | |
1269 | * the channels are free. This gives much better TCP | |
1270 | * performance if we have a lot of channels. | |
1271 | */ | |
1272 | if (nfree == 0 || nfree < navail / 2) | |
1da177e4 LT |
1273 | return 0; /* can't take now, leave it in xmit_pending */ |
1274 | ||
1275 | /* Do protocol field compression (XXX this should be optional) */ | |
1276 | p = skb->data; | |
1277 | len = skb->len; | |
1278 | if (*p == 0) { | |
1279 | ++p; | |
1280 | --len; | |
1281 | } | |
1282 | ||
516cd15f PM |
1283 | /* |
1284 | * Decide on fragment size. | |
1285 | * We create a fragment for each free channel regardless of | |
1286 | * how small they are (i.e. even 0 length) in order to minimize | |
1287 | * the time that it will take to detect when a channel drops | |
1288 | * a fragment. | |
1289 | */ | |
1da177e4 | 1290 | fragsize = len; |
516cd15f | 1291 | if (nfree > 1) |
57cd5f75 | 1292 | fragsize = DIV_ROUND_UP(fragsize, nfree); |
516cd15f PM |
1293 | /* nbigger channels get fragsize bytes, the rest get fragsize-1, |
1294 | except if nbigger==0, then they all get fragsize. */ | |
1295 | nbigger = len % nfree; | |
1da177e4 LT |
1296 | |
1297 | /* skip to the channel after the one we last used | |
1298 | and start at that one */ | |
81616c5a | 1299 | list = &ppp->channels; |
1da177e4 LT |
1300 | for (i = 0; i < ppp->nxchan; ++i) { |
1301 | list = list->next; | |
1302 | if (list == &ppp->channels) { | |
1303 | i = 0; | |
1304 | break; | |
1305 | } | |
1306 | } | |
1307 | ||
1308 | /* create a fragment for each channel */ | |
1309 | bits = B; | |
516cd15f | 1310 | while (nfree > 0 || len > 0) { |
1da177e4 LT |
1311 | list = list->next; |
1312 | if (list == &ppp->channels) { | |
1313 | i = 0; | |
1314 | continue; | |
1315 | } | |
1316 | pch = list_entry(list, struct channel, clist); | |
1317 | ++i; | |
1318 | if (!pch->avail) | |
1319 | continue; | |
1320 | ||
516cd15f PM |
1321 | /* |
1322 | * Skip this channel if it has a fragment pending already and | |
1323 | * we haven't given a fragment to all of the free channels. | |
1324 | */ | |
1325 | if (pch->avail == 1) { | |
1326 | if (nfree > 0) | |
1327 | continue; | |
1328 | } else { | |
1329 | --nfree; | |
1330 | pch->avail = 1; | |
1331 | } | |
1332 | ||
1da177e4 LT |
1333 | /* check the channel's mtu and whether it is still attached. */ |
1334 | spin_lock_bh(&pch->downl); | |
516cd15f PM |
1335 | if (pch->chan == NULL) { |
1336 | /* can't use this channel, it's being deregistered */ | |
1da177e4 LT |
1337 | spin_unlock_bh(&pch->downl); |
1338 | pch->avail = 0; | |
516cd15f | 1339 | if (--navail == 0) |
1da177e4 LT |
1340 | break; |
1341 | continue; | |
1342 | } | |
1343 | ||
1344 | /* | |
516cd15f PM |
1345 | * Create a fragment for this channel of |
1346 | * min(max(mtu+2-hdrlen, 4), fragsize, len) bytes. | |
1347 | * If mtu+2-hdrlen < 4, that is a ridiculously small | |
1348 | * MTU, so we use mtu = 2 + hdrlen. | |
1da177e4 LT |
1349 | */ |
1350 | if (fragsize > len) | |
1351 | fragsize = len; | |
516cd15f PM |
1352 | flen = fragsize; |
1353 | mtu = pch->chan->mtu + 2 - hdrlen; | |
1354 | if (mtu < 4) | |
1355 | mtu = 4; | |
1356 | if (flen > mtu) | |
1357 | flen = mtu; | |
1358 | if (flen == len && nfree == 0) | |
1359 | bits |= E; | |
1360 | frag = alloc_skb(flen + hdrlen + (flen == 0), GFP_ATOMIC); | |
cd228d54 | 1361 | if (!frag) |
516cd15f PM |
1362 | goto noskb; |
1363 | q = skb_put(frag, flen + hdrlen); | |
1364 | ||
1365 | /* make the MP header */ | |
1366 | q[0] = PPP_MP >> 8; | |
1367 | q[1] = PPP_MP; | |
1368 | if (ppp->flags & SC_MP_XSHORTSEQ) { | |
1369 | q[2] = bits + ((ppp->nxseq >> 8) & 0xf); | |
1370 | q[3] = ppp->nxseq; | |
1371 | } else { | |
1372 | q[2] = bits; | |
1373 | q[3] = ppp->nxseq >> 16; | |
1374 | q[4] = ppp->nxseq >> 8; | |
1375 | q[5] = ppp->nxseq; | |
1da177e4 | 1376 | } |
516cd15f PM |
1377 | |
1378 | /* | |
1379 | * Copy the data in. | |
1380 | * Unfortunately there is a bug in older versions of | |
1381 | * the Linux PPP multilink reconstruction code where it | |
1382 | * drops 0-length fragments. Therefore we make sure the | |
1383 | * fragment has at least one byte of data. Any bytes | |
1384 | * we add in this situation will end up as padding on the | |
1385 | * end of the reconstructed packet. | |
1386 | */ | |
1387 | if (flen == 0) | |
1388 | *skb_put(frag, 1) = 0; | |
1389 | else | |
1390 | memcpy(q + hdrlen, p, flen); | |
1391 | ||
1392 | /* try to send it down the channel */ | |
1393 | chan = pch->chan; | |
b03efcfb DM |
1394 | if (!skb_queue_empty(&pch->file.xq) || |
1395 | !chan->ops->start_xmit(chan, frag)) | |
516cd15f PM |
1396 | skb_queue_tail(&pch->file.xq, frag); |
1397 | pch->had_frag = 1; | |
1398 | p += flen; | |
1399 | len -= flen; | |
1400 | ++ppp->nxseq; | |
1401 | bits = 0; | |
1da177e4 | 1402 | spin_unlock_bh(&pch->downl); |
516cd15f PM |
1403 | |
1404 | if (--nbigger == 0 && fragsize > 0) | |
1405 | --fragsize; | |
1406 | } | |
1da177e4 LT |
1407 | ppp->nxchan = i; |
1408 | ||
1409 | return 1; | |
1410 | ||
1411 | noskb: | |
1412 | spin_unlock_bh(&pch->downl); | |
1413 | if (ppp->debug & 1) | |
1414 | printk(KERN_ERR "PPP: no memory (fragment)\n"); | |
8c0469cd | 1415 | ++ppp->dev->stats.tx_errors; |
1da177e4 LT |
1416 | ++ppp->nxseq; |
1417 | return 1; /* abandon the frame */ | |
1418 | } | |
1419 | #endif /* CONFIG_PPP_MULTILINK */ | |
1420 | ||
1421 | /* | |
1422 | * Try to send data out on a channel. | |
1423 | */ | |
1424 | static void | |
1425 | ppp_channel_push(struct channel *pch) | |
1426 | { | |
1427 | struct sk_buff *skb; | |
1428 | struct ppp *ppp; | |
1429 | ||
1430 | spin_lock_bh(&pch->downl); | |
cd228d54 | 1431 | if (pch->chan) { |
b03efcfb | 1432 | while (!skb_queue_empty(&pch->file.xq)) { |
1da177e4 LT |
1433 | skb = skb_dequeue(&pch->file.xq); |
1434 | if (!pch->chan->ops->start_xmit(pch->chan, skb)) { | |
1435 | /* put the packet back and try again later */ | |
1436 | skb_queue_head(&pch->file.xq, skb); | |
1437 | break; | |
1438 | } | |
1439 | } | |
1440 | } else { | |
1441 | /* channel got deregistered */ | |
1442 | skb_queue_purge(&pch->file.xq); | |
1443 | } | |
1444 | spin_unlock_bh(&pch->downl); | |
1445 | /* see if there is anything from the attached unit to be sent */ | |
b03efcfb | 1446 | if (skb_queue_empty(&pch->file.xq)) { |
1da177e4 LT |
1447 | read_lock_bh(&pch->upl); |
1448 | ppp = pch->ppp; | |
cd228d54 | 1449 | if (ppp) |
1da177e4 LT |
1450 | ppp_xmit_process(ppp); |
1451 | read_unlock_bh(&pch->upl); | |
1452 | } | |
1453 | } | |
1454 | ||
1455 | /* | |
1456 | * Receive-side routines. | |
1457 | */ | |
1458 | ||
1459 | /* misuse a few fields of the skb for MP reconstruction */ | |
1460 | #define sequence priority | |
1461 | #define BEbits cb[0] | |
1462 | ||
1463 | static inline void | |
1464 | ppp_do_recv(struct ppp *ppp, struct sk_buff *skb, struct channel *pch) | |
1465 | { | |
1466 | ppp_recv_lock(ppp); | |
739840d5 | 1467 | if (!ppp->closing) |
1da177e4 LT |
1468 | ppp_receive_frame(ppp, skb, pch); |
1469 | else | |
1470 | kfree_skb(skb); | |
1471 | ppp_recv_unlock(ppp); | |
1472 | } | |
1473 | ||
1474 | void | |
1475 | ppp_input(struct ppp_channel *chan, struct sk_buff *skb) | |
1476 | { | |
1477 | struct channel *pch = chan->ppp; | |
1478 | int proto; | |
1479 | ||
cd228d54 | 1480 | if (!pch || skb->len == 0) { |
1da177e4 LT |
1481 | kfree_skb(skb); |
1482 | return; | |
1483 | } | |
516cd15f | 1484 | |
1da177e4 LT |
1485 | proto = PPP_PROTO(skb); |
1486 | read_lock_bh(&pch->upl); | |
cd228d54 | 1487 | if (!pch->ppp || proto >= 0xc000 || proto == PPP_CCPFRAG) { |
1da177e4 LT |
1488 | /* put it on the channel queue */ |
1489 | skb_queue_tail(&pch->file.rq, skb); | |
1490 | /* drop old frames if queue too long */ | |
1491 | while (pch->file.rq.qlen > PPP_MAX_RQLEN | |
cd228d54 | 1492 | && (skb = skb_dequeue(&pch->file.rq))) |
1da177e4 LT |
1493 | kfree_skb(skb); |
1494 | wake_up_interruptible(&pch->file.rwait); | |
1495 | } else { | |
1496 | ppp_do_recv(pch->ppp, skb, pch); | |
1497 | } | |
1498 | read_unlock_bh(&pch->upl); | |
1499 | } | |
1500 | ||
1501 | /* Put a 0-length skb in the receive queue as an error indication */ | |
1502 | void | |
1503 | ppp_input_error(struct ppp_channel *chan, int code) | |
1504 | { | |
1505 | struct channel *pch = chan->ppp; | |
1506 | struct sk_buff *skb; | |
1507 | ||
cd228d54 | 1508 | if (!pch) |
1da177e4 LT |
1509 | return; |
1510 | ||
1511 | read_lock_bh(&pch->upl); | |
cd228d54 | 1512 | if (pch->ppp) { |
1da177e4 | 1513 | skb = alloc_skb(0, GFP_ATOMIC); |
cd228d54 | 1514 | if (skb) { |
1da177e4 LT |
1515 | skb->len = 0; /* probably unnecessary */ |
1516 | skb->cb[0] = code; | |
1517 | ppp_do_recv(pch->ppp, skb, pch); | |
1518 | } | |
1519 | } | |
1520 | read_unlock_bh(&pch->upl); | |
1521 | } | |
1522 | ||
1523 | /* | |
1524 | * We come in here to process a received frame. | |
1525 | * The receive side of the ppp unit is locked. | |
1526 | */ | |
1527 | static void | |
1528 | ppp_receive_frame(struct ppp *ppp, struct sk_buff *skb, struct channel *pch) | |
1529 | { | |
2a38b775 | 1530 | if (pskb_may_pull(skb, 2)) { |
1da177e4 LT |
1531 | #ifdef CONFIG_PPP_MULTILINK |
1532 | /* XXX do channel-level decompression here */ | |
1533 | if (PPP_PROTO(skb) == PPP_MP) | |
1534 | ppp_receive_mp_frame(ppp, skb, pch); | |
1535 | else | |
1536 | #endif /* CONFIG_PPP_MULTILINK */ | |
1537 | ppp_receive_nonmp_frame(ppp, skb); | |
1538 | return; | |
1539 | } | |
1540 | ||
1541 | if (skb->len > 0) | |
1542 | /* note: a 0-length skb is used as an error indication */ | |
8c0469cd | 1543 | ++ppp->dev->stats.rx_length_errors; |
1da177e4 LT |
1544 | |
1545 | kfree_skb(skb); | |
1546 | ppp_receive_error(ppp); | |
1547 | } | |
1548 | ||
1549 | static void | |
1550 | ppp_receive_error(struct ppp *ppp) | |
1551 | { | |
8c0469cd | 1552 | ++ppp->dev->stats.rx_errors; |
cd228d54 | 1553 | if (ppp->vj) |
1da177e4 LT |
1554 | slhc_toss(ppp->vj); |
1555 | } | |
1556 | ||
1557 | static void | |
1558 | ppp_receive_nonmp_frame(struct ppp *ppp, struct sk_buff *skb) | |
1559 | { | |
1560 | struct sk_buff *ns; | |
1561 | int proto, len, npi; | |
1562 | ||
1563 | /* | |
1564 | * Decompress the frame, if compressed. | |
1565 | * Note that some decompressors need to see uncompressed frames | |
1566 | * that come in as well as compressed frames. | |
1567 | */ | |
cd228d54 | 1568 | if (ppp->rc_state && (ppp->rstate & SC_DECOMP_RUN) |
1da177e4 LT |
1569 | && (ppp->rstate & (SC_DC_FERROR | SC_DC_ERROR)) == 0) |
1570 | skb = ppp_decompress_frame(ppp, skb); | |
1571 | ||
b3f9b92a MD |
1572 | if (ppp->flags & SC_MUST_COMP && ppp->rstate & SC_DC_FERROR) |
1573 | goto err; | |
1574 | ||
1da177e4 LT |
1575 | proto = PPP_PROTO(skb); |
1576 | switch (proto) { | |
1577 | case PPP_VJC_COMP: | |
1578 | /* decompress VJ compressed packets */ | |
cd228d54 | 1579 | if (!ppp->vj || (ppp->flags & SC_REJ_COMP_TCP)) |
1da177e4 LT |
1580 | goto err; |
1581 | ||
2a38b775 | 1582 | if (skb_tailroom(skb) < 124 || skb_cloned(skb)) { |
1da177e4 LT |
1583 | /* copy to a new sk_buff with more tailroom */ |
1584 | ns = dev_alloc_skb(skb->len + 128); | |
cd228d54 | 1585 | if (!ns) { |
1da177e4 LT |
1586 | printk(KERN_ERR"PPP: no memory (VJ decomp)\n"); |
1587 | goto err; | |
1588 | } | |
1589 | skb_reserve(ns, 2); | |
1590 | skb_copy_bits(skb, 0, skb_put(ns, skb->len), skb->len); | |
1591 | kfree_skb(skb); | |
1592 | skb = ns; | |
1593 | } | |
e3f749c4 HX |
1594 | else |
1595 | skb->ip_summed = CHECKSUM_NONE; | |
1da177e4 LT |
1596 | |
1597 | len = slhc_uncompress(ppp->vj, skb->data + 2, skb->len - 2); | |
1598 | if (len <= 0) { | |
1599 | printk(KERN_DEBUG "PPP: VJ decompression error\n"); | |
1600 | goto err; | |
1601 | } | |
1602 | len += 2; | |
1603 | if (len > skb->len) | |
1604 | skb_put(skb, len - skb->len); | |
1605 | else if (len < skb->len) | |
1606 | skb_trim(skb, len); | |
1607 | proto = PPP_IP; | |
1608 | break; | |
1609 | ||
1610 | case PPP_VJC_UNCOMP: | |
cd228d54 | 1611 | if (!ppp->vj || (ppp->flags & SC_REJ_COMP_TCP)) |
1da177e4 | 1612 | goto err; |
6aa20a22 | 1613 | |
1da177e4 LT |
1614 | /* Until we fix the decompressor need to make sure |
1615 | * data portion is linear. | |
1616 | */ | |
6aa20a22 | 1617 | if (!pskb_may_pull(skb, skb->len)) |
1da177e4 LT |
1618 | goto err; |
1619 | ||
1620 | if (slhc_remember(ppp->vj, skb->data + 2, skb->len - 2) <= 0) { | |
1621 | printk(KERN_ERR "PPP: VJ uncompressed error\n"); | |
1622 | goto err; | |
1623 | } | |
1624 | proto = PPP_IP; | |
1625 | break; | |
1626 | ||
1627 | case PPP_CCP: | |
1628 | ppp_ccp_peek(ppp, skb, 1); | |
1629 | break; | |
1630 | } | |
1631 | ||
8c0469cd PZ |
1632 | ++ppp->dev->stats.rx_packets; |
1633 | ppp->dev->stats.rx_bytes += skb->len - 2; | |
1da177e4 LT |
1634 | |
1635 | npi = proto_to_npindex(proto); | |
1636 | if (npi < 0) { | |
1637 | /* control or unknown frame - pass it to pppd */ | |
1638 | skb_queue_tail(&ppp->file.rq, skb); | |
1639 | /* limit queue length by dropping old frames */ | |
1640 | while (ppp->file.rq.qlen > PPP_MAX_RQLEN | |
cd228d54 | 1641 | && (skb = skb_dequeue(&ppp->file.rq))) |
1da177e4 LT |
1642 | kfree_skb(skb); |
1643 | /* wake up any process polling or blocking on read */ | |
1644 | wake_up_interruptible(&ppp->file.rwait); | |
1645 | ||
1646 | } else { | |
1647 | /* network protocol frame - give it to the kernel */ | |
1648 | ||
1649 | #ifdef CONFIG_PPP_FILTER | |
1650 | /* check if the packet passes the pass and active filters */ | |
1651 | /* the filter instructions are constructed assuming | |
1652 | a four-byte PPP header on each packet */ | |
2a38b775 HX |
1653 | if (ppp->pass_filter || ppp->active_filter) { |
1654 | if (skb_cloned(skb) && | |
1655 | pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) | |
1656 | goto err; | |
1657 | ||
1658 | *skb_push(skb, 2) = 0; | |
1659 | if (ppp->pass_filter | |
1660 | && sk_run_filter(skb, ppp->pass_filter, | |
1661 | ppp->pass_len) == 0) { | |
1662 | if (ppp->debug & 1) | |
1663 | printk(KERN_DEBUG "PPP: inbound frame " | |
1664 | "not passed\n"); | |
1665 | kfree_skb(skb); | |
1666 | return; | |
1667 | } | |
1668 | if (!(ppp->active_filter | |
1669 | && sk_run_filter(skb, ppp->active_filter, | |
1670 | ppp->active_len) == 0)) | |
1671 | ppp->last_recv = jiffies; | |
1672 | __skb_pull(skb, 2); | |
1673 | } else | |
1da177e4 | 1674 | #endif /* CONFIG_PPP_FILTER */ |
2a38b775 | 1675 | ppp->last_recv = jiffies; |
1da177e4 LT |
1676 | |
1677 | if ((ppp->dev->flags & IFF_UP) == 0 | |
1678 | || ppp->npmode[npi] != NPMODE_PASS) { | |
1679 | kfree_skb(skb); | |
1680 | } else { | |
cbb042f9 HX |
1681 | /* chop off protocol */ |
1682 | skb_pull_rcsum(skb, 2); | |
1da177e4 LT |
1683 | skb->dev = ppp->dev; |
1684 | skb->protocol = htons(npindex_to_ethertype[npi]); | |
459a98ed | 1685 | skb_reset_mac_header(skb); |
1da177e4 LT |
1686 | netif_rx(skb); |
1687 | ppp->dev->last_rx = jiffies; | |
1688 | } | |
1689 | } | |
1690 | return; | |
1691 | ||
1692 | err: | |
1693 | kfree_skb(skb); | |
1694 | ppp_receive_error(ppp); | |
1695 | } | |
1696 | ||
1697 | static struct sk_buff * | |
1698 | ppp_decompress_frame(struct ppp *ppp, struct sk_buff *skb) | |
1699 | { | |
1700 | int proto = PPP_PROTO(skb); | |
1701 | struct sk_buff *ns; | |
1702 | int len; | |
1703 | ||
1704 | /* Until we fix all the decompressor's need to make sure | |
1705 | * data portion is linear. | |
1706 | */ | |
1707 | if (!pskb_may_pull(skb, skb->len)) | |
1708 | goto err; | |
1709 | ||
1710 | if (proto == PPP_COMP) { | |
4b2a8fb3 KS |
1711 | int obuff_size; |
1712 | ||
1713 | switch(ppp->rcomp->compress_proto) { | |
1714 | case CI_MPPE: | |
1715 | obuff_size = ppp->mru + PPP_HDRLEN + 1; | |
1716 | break; | |
1717 | default: | |
1718 | obuff_size = ppp->mru + PPP_HDRLEN; | |
1719 | break; | |
1720 | } | |
1721 | ||
1722 | ns = dev_alloc_skb(obuff_size); | |
cd228d54 | 1723 | if (!ns) { |
1da177e4 LT |
1724 | printk(KERN_ERR "ppp_decompress_frame: no memory\n"); |
1725 | goto err; | |
1726 | } | |
1727 | /* the decompressor still expects the A/C bytes in the hdr */ | |
1728 | len = ppp->rcomp->decompress(ppp->rc_state, skb->data - 2, | |
06c7af56 | 1729 | skb->len + 2, ns->data, obuff_size); |
1da177e4 LT |
1730 | if (len < 0) { |
1731 | /* Pass the compressed frame to pppd as an | |
1732 | error indication. */ | |
1733 | if (len == DECOMP_FATALERROR) | |
1734 | ppp->rstate |= SC_DC_FERROR; | |
1735 | kfree_skb(ns); | |
1736 | goto err; | |
1737 | } | |
1738 | ||
1739 | kfree_skb(skb); | |
1740 | skb = ns; | |
1741 | skb_put(skb, len); | |
1742 | skb_pull(skb, 2); /* pull off the A/C bytes */ | |
1743 | ||
1744 | } else { | |
1745 | /* Uncompressed frame - pass to decompressor so it | |
1746 | can update its dictionary if necessary. */ | |
1747 | if (ppp->rcomp->incomp) | |
1748 | ppp->rcomp->incomp(ppp->rc_state, skb->data - 2, | |
1749 | skb->len + 2); | |
1750 | } | |
1751 | ||
1752 | return skb; | |
1753 | ||
1754 | err: | |
1755 | ppp->rstate |= SC_DC_ERROR; | |
1756 | ppp_receive_error(ppp); | |
1757 | return skb; | |
1758 | } | |
1759 | ||
1760 | #ifdef CONFIG_PPP_MULTILINK | |
1761 | /* | |
1762 | * Receive a multilink frame. | |
1763 | * We put it on the reconstruction queue and then pull off | |
1764 | * as many completed frames as we can. | |
1765 | */ | |
1766 | static void | |
1767 | ppp_receive_mp_frame(struct ppp *ppp, struct sk_buff *skb, struct channel *pch) | |
1768 | { | |
1769 | u32 mask, seq; | |
81616c5a | 1770 | struct channel *ch; |
1da177e4 LT |
1771 | int mphdrlen = (ppp->flags & SC_MP_SHORTSEQ)? MPHDRLEN_SSN: MPHDRLEN; |
1772 | ||
2a38b775 | 1773 | if (!pskb_may_pull(skb, mphdrlen + 1) || ppp->mrru == 0) |
1da177e4 LT |
1774 | goto err; /* no good, throw it away */ |
1775 | ||
1776 | /* Decode sequence number and begin/end bits */ | |
1777 | if (ppp->flags & SC_MP_SHORTSEQ) { | |
1778 | seq = ((skb->data[2] & 0x0f) << 8) | skb->data[3]; | |
1779 | mask = 0xfff; | |
1780 | } else { | |
1781 | seq = (skb->data[3] << 16) | (skb->data[4] << 8)| skb->data[5]; | |
1782 | mask = 0xffffff; | |
1783 | } | |
1784 | skb->BEbits = skb->data[2]; | |
1785 | skb_pull(skb, mphdrlen); /* pull off PPP and MP headers */ | |
1786 | ||
1787 | /* | |
1788 | * Do protocol ID decompression on the first fragment of each packet. | |
1789 | */ | |
1790 | if ((skb->BEbits & B) && (skb->data[0] & 1)) | |
1791 | *skb_push(skb, 1) = 0; | |
1792 | ||
1793 | /* | |
1794 | * Expand sequence number to 32 bits, making it as close | |
1795 | * as possible to ppp->minseq. | |
1796 | */ | |
1797 | seq |= ppp->minseq & ~mask; | |
1798 | if ((int)(ppp->minseq - seq) > (int)(mask >> 1)) | |
1799 | seq += mask + 1; | |
1800 | else if ((int)(seq - ppp->minseq) > (int)(mask >> 1)) | |
1801 | seq -= mask + 1; /* should never happen */ | |
1802 | skb->sequence = seq; | |
1803 | pch->lastseq = seq; | |
1804 | ||
1805 | /* | |
1806 | * If this packet comes before the next one we were expecting, | |
1807 | * drop it. | |
1808 | */ | |
1809 | if (seq_before(seq, ppp->nextseq)) { | |
1810 | kfree_skb(skb); | |
8c0469cd | 1811 | ++ppp->dev->stats.rx_dropped; |
1da177e4 LT |
1812 | ppp_receive_error(ppp); |
1813 | return; | |
1814 | } | |
1815 | ||
1816 | /* | |
1817 | * Reevaluate minseq, the minimum over all channels of the | |
1818 | * last sequence number received on each channel. Because of | |
1819 | * the increasing sequence number rule, we know that any fragment | |
1820 | * before `minseq' which hasn't arrived is never going to arrive. | |
1821 | * The list of channels can't change because we have the receive | |
1822 | * side of the ppp unit locked. | |
1823 | */ | |
81616c5a | 1824 | list_for_each_entry(ch, &ppp->channels, clist) { |
1da177e4 LT |
1825 | if (seq_before(ch->lastseq, seq)) |
1826 | seq = ch->lastseq; | |
1827 | } | |
1828 | if (seq_before(ppp->minseq, seq)) | |
1829 | ppp->minseq = seq; | |
1830 | ||
1831 | /* Put the fragment on the reconstruction queue */ | |
1832 | ppp_mp_insert(ppp, skb); | |
1833 | ||
1834 | /* If the queue is getting long, don't wait any longer for packets | |
1835 | before the start of the queue. */ | |
38ce7c73 DM |
1836 | if (skb_queue_len(&ppp->mrq) >= PPP_MP_MAX_QLEN) { |
1837 | struct sk_buff *skb = skb_peek(&ppp->mrq); | |
1838 | if (seq_before(ppp->minseq, skb->sequence)) | |
1839 | ppp->minseq = skb->sequence; | |
1840 | } | |
1da177e4 LT |
1841 | |
1842 | /* Pull completed packets off the queue and receive them. */ | |
cd228d54 | 1843 | while ((skb = ppp_mp_reconstruct(ppp))) |
1da177e4 LT |
1844 | ppp_receive_nonmp_frame(ppp, skb); |
1845 | ||
1846 | return; | |
1847 | ||
1848 | err: | |
1849 | kfree_skb(skb); | |
1850 | ppp_receive_error(ppp); | |
1851 | } | |
1852 | ||
1853 | /* | |
1854 | * Insert a fragment on the MP reconstruction queue. | |
1855 | * The queue is ordered by increasing sequence number. | |
1856 | */ | |
1857 | static void | |
1858 | ppp_mp_insert(struct ppp *ppp, struct sk_buff *skb) | |
1859 | { | |
1860 | struct sk_buff *p; | |
1861 | struct sk_buff_head *list = &ppp->mrq; | |
1862 | u32 seq = skb->sequence; | |
1863 | ||
1864 | /* N.B. we don't need to lock the list lock because we have the | |
1865 | ppp unit receive-side lock. */ | |
13c9821e | 1866 | skb_queue_walk(list, p) { |
1da177e4 LT |
1867 | if (seq_before(seq, p->sequence)) |
1868 | break; | |
13c9821e | 1869 | } |
43f59c89 | 1870 | __skb_queue_before(list, p, skb); |
1da177e4 LT |
1871 | } |
1872 | ||
1873 | /* | |
1874 | * Reconstruct a packet from the MP fragment queue. | |
1875 | * We go through increasing sequence numbers until we find a | |
1876 | * complete packet, or we get to the sequence number for a fragment | |
1877 | * which hasn't arrived but might still do so. | |
1878 | */ | |
3c582b30 | 1879 | static struct sk_buff * |
1da177e4 LT |
1880 | ppp_mp_reconstruct(struct ppp *ppp) |
1881 | { | |
1882 | u32 seq = ppp->nextseq; | |
1883 | u32 minseq = ppp->minseq; | |
1884 | struct sk_buff_head *list = &ppp->mrq; | |
1885 | struct sk_buff *p, *next; | |
1886 | struct sk_buff *head, *tail; | |
1887 | struct sk_buff *skb = NULL; | |
1888 | int lost = 0, len = 0; | |
1889 | ||
1890 | if (ppp->mrru == 0) /* do nothing until mrru is set */ | |
1891 | return NULL; | |
1892 | head = list->next; | |
1893 | tail = NULL; | |
1894 | for (p = head; p != (struct sk_buff *) list; p = next) { | |
1895 | next = p->next; | |
1896 | if (seq_before(p->sequence, seq)) { | |
1897 | /* this can't happen, anyway ignore the skb */ | |
1898 | printk(KERN_ERR "ppp_mp_reconstruct bad seq %u < %u\n", | |
1899 | p->sequence, seq); | |
1900 | head = next; | |
1901 | continue; | |
1902 | } | |
1903 | if (p->sequence != seq) { | |
1904 | /* Fragment `seq' is missing. If it is after | |
1905 | minseq, it might arrive later, so stop here. */ | |
1906 | if (seq_after(seq, minseq)) | |
1907 | break; | |
1908 | /* Fragment `seq' is lost, keep going. */ | |
1909 | lost = 1; | |
1910 | seq = seq_before(minseq, p->sequence)? | |
1911 | minseq + 1: p->sequence; | |
1912 | next = p; | |
1913 | continue; | |
1914 | } | |
1915 | ||
1916 | /* | |
1917 | * At this point we know that all the fragments from | |
1918 | * ppp->nextseq to seq are either present or lost. | |
1919 | * Also, there are no complete packets in the queue | |
1920 | * that have no missing fragments and end before this | |
1921 | * fragment. | |
1922 | */ | |
1923 | ||
1924 | /* B bit set indicates this fragment starts a packet */ | |
1925 | if (p->BEbits & B) { | |
1926 | head = p; | |
1927 | lost = 0; | |
1928 | len = 0; | |
1929 | } | |
1930 | ||
1931 | len += p->len; | |
1932 | ||
1933 | /* Got a complete packet yet? */ | |
1934 | if (lost == 0 && (p->BEbits & E) && (head->BEbits & B)) { | |
1935 | if (len > ppp->mrru + 2) { | |
8c0469cd | 1936 | ++ppp->dev->stats.rx_length_errors; |
1da177e4 LT |
1937 | printk(KERN_DEBUG "PPP: reconstructed packet" |
1938 | " is too long (%d)\n", len); | |
1939 | } else if (p == head) { | |
1940 | /* fragment is complete packet - reuse skb */ | |
1941 | tail = p; | |
1942 | skb = skb_get(p); | |
1943 | break; | |
1944 | } else if ((skb = dev_alloc_skb(len)) == NULL) { | |
8c0469cd | 1945 | ++ppp->dev->stats.rx_missed_errors; |
1da177e4 LT |
1946 | printk(KERN_DEBUG "PPP: no memory for " |
1947 | "reconstructed packet"); | |
1948 | } else { | |
1949 | tail = p; | |
1950 | break; | |
1951 | } | |
1952 | ppp->nextseq = seq + 1; | |
1953 | } | |
1954 | ||
1955 | /* | |
1956 | * If this is the ending fragment of a packet, | |
1957 | * and we haven't found a complete valid packet yet, | |
1958 | * we can discard up to and including this fragment. | |
1959 | */ | |
1960 | if (p->BEbits & E) | |
1961 | head = next; | |
1962 | ||
1963 | ++seq; | |
1964 | } | |
1965 | ||
1966 | /* If we have a complete packet, copy it all into one skb. */ | |
1967 | if (tail != NULL) { | |
1968 | /* If we have discarded any fragments, | |
1969 | signal a receive error. */ | |
1970 | if (head->sequence != ppp->nextseq) { | |
1971 | if (ppp->debug & 1) | |
1972 | printk(KERN_DEBUG " missed pkts %u..%u\n", | |
1973 | ppp->nextseq, head->sequence-1); | |
8c0469cd | 1974 | ++ppp->dev->stats.rx_dropped; |
1da177e4 LT |
1975 | ppp_receive_error(ppp); |
1976 | } | |
1977 | ||
1978 | if (head != tail) | |
1979 | /* copy to a single skb */ | |
1980 | for (p = head; p != tail->next; p = p->next) | |
1981 | skb_copy_bits(p, 0, skb_put(skb, p->len), p->len); | |
1982 | ppp->nextseq = tail->sequence + 1; | |
1983 | head = tail->next; | |
1984 | } | |
1985 | ||
1986 | /* Discard all the skbuffs that we have copied the data out of | |
1987 | or that we can't use. */ | |
1988 | while ((p = list->next) != head) { | |
1989 | __skb_unlink(p, list); | |
1990 | kfree_skb(p); | |
1991 | } | |
1992 | ||
1993 | return skb; | |
1994 | } | |
1995 | #endif /* CONFIG_PPP_MULTILINK */ | |
1996 | ||
1997 | /* | |
1998 | * Channel interface. | |
1999 | */ | |
2000 | ||
2001 | /* | |
2002 | * Create a new, unattached ppp channel. | |
2003 | */ | |
2004 | int | |
2005 | ppp_register_channel(struct ppp_channel *chan) | |
2006 | { | |
2007 | struct channel *pch; | |
2008 | ||
d4274b51 | 2009 | pch = kzalloc(sizeof(struct channel), GFP_KERNEL); |
cd228d54 | 2010 | if (!pch) |
1da177e4 | 2011 | return -ENOMEM; |
1da177e4 LT |
2012 | pch->ppp = NULL; |
2013 | pch->chan = chan; | |
2014 | chan->ppp = pch; | |
2015 | init_ppp_file(&pch->file, CHANNEL); | |
2016 | pch->file.hdrlen = chan->hdrlen; | |
2017 | #ifdef CONFIG_PPP_MULTILINK | |
2018 | pch->lastseq = -1; | |
2019 | #endif /* CONFIG_PPP_MULTILINK */ | |
2020 | init_rwsem(&pch->chan_sem); | |
2021 | spin_lock_init(&pch->downl); | |
2022 | rwlock_init(&pch->upl); | |
2023 | spin_lock_bh(&all_channels_lock); | |
2024 | pch->file.index = ++last_channel_index; | |
2025 | list_add(&pch->list, &new_channels); | |
2026 | atomic_inc(&channel_count); | |
2027 | spin_unlock_bh(&all_channels_lock); | |
2028 | return 0; | |
2029 | } | |
2030 | ||
2031 | /* | |
2032 | * Return the index of a channel. | |
2033 | */ | |
2034 | int ppp_channel_index(struct ppp_channel *chan) | |
2035 | { | |
2036 | struct channel *pch = chan->ppp; | |
2037 | ||
cd228d54 | 2038 | if (pch) |
1da177e4 LT |
2039 | return pch->file.index; |
2040 | return -1; | |
2041 | } | |
2042 | ||
2043 | /* | |
2044 | * Return the PPP unit number to which a channel is connected. | |
2045 | */ | |
2046 | int ppp_unit_number(struct ppp_channel *chan) | |
2047 | { | |
2048 | struct channel *pch = chan->ppp; | |
2049 | int unit = -1; | |
2050 | ||
cd228d54 | 2051 | if (pch) { |
1da177e4 | 2052 | read_lock_bh(&pch->upl); |
cd228d54 | 2053 | if (pch->ppp) |
1da177e4 LT |
2054 | unit = pch->ppp->file.index; |
2055 | read_unlock_bh(&pch->upl); | |
2056 | } | |
2057 | return unit; | |
2058 | } | |
2059 | ||
2060 | /* | |
2061 | * Disconnect a channel from the generic layer. | |
2062 | * This must be called in process context. | |
2063 | */ | |
2064 | void | |
2065 | ppp_unregister_channel(struct ppp_channel *chan) | |
2066 | { | |
2067 | struct channel *pch = chan->ppp; | |
2068 | ||
cd228d54 | 2069 | if (!pch) |
1da177e4 LT |
2070 | return; /* should never happen */ |
2071 | chan->ppp = NULL; | |
2072 | ||
2073 | /* | |
2074 | * This ensures that we have returned from any calls into the | |
2075 | * the channel's start_xmit or ioctl routine before we proceed. | |
2076 | */ | |
2077 | down_write(&pch->chan_sem); | |
2078 | spin_lock_bh(&pch->downl); | |
2079 | pch->chan = NULL; | |
2080 | spin_unlock_bh(&pch->downl); | |
2081 | up_write(&pch->chan_sem); | |
2082 | ppp_disconnect_channel(pch); | |
2083 | spin_lock_bh(&all_channels_lock); | |
2084 | list_del(&pch->list); | |
2085 | spin_unlock_bh(&all_channels_lock); | |
2086 | pch->file.dead = 1; | |
2087 | wake_up_interruptible(&pch->file.rwait); | |
2088 | if (atomic_dec_and_test(&pch->file.refcnt)) | |
2089 | ppp_destroy_channel(pch); | |
2090 | } | |
2091 | ||
2092 | /* | |
2093 | * Callback from a channel when it can accept more to transmit. | |
2094 | * This should be called at BH/softirq level, not interrupt level. | |
2095 | */ | |
2096 | void | |
2097 | ppp_output_wakeup(struct ppp_channel *chan) | |
2098 | { | |
2099 | struct channel *pch = chan->ppp; | |
2100 | ||
cd228d54 | 2101 | if (!pch) |
1da177e4 LT |
2102 | return; |
2103 | ppp_channel_push(pch); | |
2104 | } | |
2105 | ||
2106 | /* | |
2107 | * Compression control. | |
2108 | */ | |
2109 | ||
2110 | /* Process the PPPIOCSCOMPRESS ioctl. */ | |
2111 | static int | |
2112 | ppp_set_compress(struct ppp *ppp, unsigned long arg) | |
2113 | { | |
2114 | int err; | |
2115 | struct compressor *cp, *ocomp; | |
2116 | struct ppp_option_data data; | |
2117 | void *state, *ostate; | |
2118 | unsigned char ccp_option[CCP_MAX_OPTION_LENGTH]; | |
2119 | ||
2120 | err = -EFAULT; | |
2121 | if (copy_from_user(&data, (void __user *) arg, sizeof(data)) | |
2122 | || (data.length <= CCP_MAX_OPTION_LENGTH | |
2123 | && copy_from_user(ccp_option, (void __user *) data.ptr, data.length))) | |
2124 | goto out; | |
2125 | err = -EINVAL; | |
2126 | if (data.length > CCP_MAX_OPTION_LENGTH | |
2127 | || ccp_option[1] < 2 || ccp_option[1] > data.length) | |
2128 | goto out; | |
2129 | ||
a65e5d78 JB |
2130 | cp = try_then_request_module( |
2131 | find_compressor(ccp_option[0]), | |
2132 | "ppp-compress-%d", ccp_option[0]); | |
cd228d54 | 2133 | if (!cp) |
1da177e4 LT |
2134 | goto out; |
2135 | ||
2136 | err = -ENOBUFS; | |
2137 | if (data.transmit) { | |
2138 | state = cp->comp_alloc(ccp_option, data.length); | |
cd228d54 | 2139 | if (state) { |
1da177e4 LT |
2140 | ppp_xmit_lock(ppp); |
2141 | ppp->xstate &= ~SC_COMP_RUN; | |
2142 | ocomp = ppp->xcomp; | |
2143 | ostate = ppp->xc_state; | |
2144 | ppp->xcomp = cp; | |
2145 | ppp->xc_state = state; | |
2146 | ppp_xmit_unlock(ppp); | |
cd228d54 | 2147 | if (ostate) { |
1da177e4 LT |
2148 | ocomp->comp_free(ostate); |
2149 | module_put(ocomp->owner); | |
2150 | } | |
2151 | err = 0; | |
2152 | } else | |
2153 | module_put(cp->owner); | |
2154 | ||
2155 | } else { | |
2156 | state = cp->decomp_alloc(ccp_option, data.length); | |
cd228d54 | 2157 | if (state) { |
1da177e4 LT |
2158 | ppp_recv_lock(ppp); |
2159 | ppp->rstate &= ~SC_DECOMP_RUN; | |
2160 | ocomp = ppp->rcomp; | |
2161 | ostate = ppp->rc_state; | |
2162 | ppp->rcomp = cp; | |
2163 | ppp->rc_state = state; | |
2164 | ppp_recv_unlock(ppp); | |
cd228d54 | 2165 | if (ostate) { |
1da177e4 LT |
2166 | ocomp->decomp_free(ostate); |
2167 | module_put(ocomp->owner); | |
2168 | } | |
2169 | err = 0; | |
2170 | } else | |
2171 | module_put(cp->owner); | |
2172 | } | |
2173 | ||
2174 | out: | |
2175 | return err; | |
2176 | } | |
2177 | ||
2178 | /* | |
2179 | * Look at a CCP packet and update our state accordingly. | |
2180 | * We assume the caller has the xmit or recv path locked. | |
2181 | */ | |
2182 | static void | |
2183 | ppp_ccp_peek(struct ppp *ppp, struct sk_buff *skb, int inbound) | |
2184 | { | |
2185 | unsigned char *dp; | |
2186 | int len; | |
2187 | ||
2188 | if (!pskb_may_pull(skb, CCP_HDRLEN + 2)) | |
2189 | return; /* no header */ | |
2190 | dp = skb->data + 2; | |
2191 | ||
2192 | switch (CCP_CODE(dp)) { | |
2193 | case CCP_CONFREQ: | |
2194 | ||
6aa20a22 | 2195 | /* A ConfReq starts negotiation of compression |
1da177e4 LT |
2196 | * in one direction of transmission, |
2197 | * and hence brings it down...but which way? | |
2198 | * | |
2199 | * Remember: | |
2200 | * A ConfReq indicates what the sender would like to receive | |
2201 | */ | |
2202 | if(inbound) | |
2203 | /* He is proposing what I should send */ | |
2204 | ppp->xstate &= ~SC_COMP_RUN; | |
6aa20a22 | 2205 | else |
1da177e4 LT |
2206 | /* I am proposing to what he should send */ |
2207 | ppp->rstate &= ~SC_DECOMP_RUN; | |
6aa20a22 | 2208 | |
1da177e4 | 2209 | break; |
6aa20a22 | 2210 | |
1da177e4 LT |
2211 | case CCP_TERMREQ: |
2212 | case CCP_TERMACK: | |
2213 | /* | |
6aa20a22 | 2214 | * CCP is going down, both directions of transmission |
1da177e4 LT |
2215 | */ |
2216 | ppp->rstate &= ~SC_DECOMP_RUN; | |
2217 | ppp->xstate &= ~SC_COMP_RUN; | |
2218 | break; | |
2219 | ||
2220 | case CCP_CONFACK: | |
2221 | if ((ppp->flags & (SC_CCP_OPEN | SC_CCP_UP)) != SC_CCP_OPEN) | |
2222 | break; | |
2223 | len = CCP_LENGTH(dp); | |
2224 | if (!pskb_may_pull(skb, len + 2)) | |
2225 | return; /* too short */ | |
2226 | dp += CCP_HDRLEN; | |
2227 | len -= CCP_HDRLEN; | |
2228 | if (len < CCP_OPT_MINLEN || len < CCP_OPT_LENGTH(dp)) | |
2229 | break; | |
2230 | if (inbound) { | |
2231 | /* we will start receiving compressed packets */ | |
cd228d54 | 2232 | if (!ppp->rc_state) |
1da177e4 LT |
2233 | break; |
2234 | if (ppp->rcomp->decomp_init(ppp->rc_state, dp, len, | |
2235 | ppp->file.index, 0, ppp->mru, ppp->debug)) { | |
2236 | ppp->rstate |= SC_DECOMP_RUN; | |
2237 | ppp->rstate &= ~(SC_DC_ERROR | SC_DC_FERROR); | |
2238 | } | |
2239 | } else { | |
2240 | /* we will soon start sending compressed packets */ | |
cd228d54 | 2241 | if (!ppp->xc_state) |
1da177e4 LT |
2242 | break; |
2243 | if (ppp->xcomp->comp_init(ppp->xc_state, dp, len, | |
2244 | ppp->file.index, 0, ppp->debug)) | |
2245 | ppp->xstate |= SC_COMP_RUN; | |
2246 | } | |
2247 | break; | |
2248 | ||
2249 | case CCP_RESETACK: | |
2250 | /* reset the [de]compressor */ | |
2251 | if ((ppp->flags & SC_CCP_UP) == 0) | |
2252 | break; | |
2253 | if (inbound) { | |
2254 | if (ppp->rc_state && (ppp->rstate & SC_DECOMP_RUN)) { | |
2255 | ppp->rcomp->decomp_reset(ppp->rc_state); | |
2256 | ppp->rstate &= ~SC_DC_ERROR; | |
2257 | } | |
2258 | } else { | |
2259 | if (ppp->xc_state && (ppp->xstate & SC_COMP_RUN)) | |
2260 | ppp->xcomp->comp_reset(ppp->xc_state); | |
2261 | } | |
2262 | break; | |
2263 | } | |
2264 | } | |
2265 | ||
2266 | /* Free up compression resources. */ | |
2267 | static void | |
2268 | ppp_ccp_closed(struct ppp *ppp) | |
2269 | { | |
2270 | void *xstate, *rstate; | |
2271 | struct compressor *xcomp, *rcomp; | |
2272 | ||
2273 | ppp_lock(ppp); | |
2274 | ppp->flags &= ~(SC_CCP_OPEN | SC_CCP_UP); | |
2275 | ppp->xstate = 0; | |
2276 | xcomp = ppp->xcomp; | |
2277 | xstate = ppp->xc_state; | |
2278 | ppp->xc_state = NULL; | |
2279 | ppp->rstate = 0; | |
2280 | rcomp = ppp->rcomp; | |
2281 | rstate = ppp->rc_state; | |
2282 | ppp->rc_state = NULL; | |
2283 | ppp_unlock(ppp); | |
2284 | ||
2285 | if (xstate) { | |
2286 | xcomp->comp_free(xstate); | |
2287 | module_put(xcomp->owner); | |
2288 | } | |
2289 | if (rstate) { | |
2290 | rcomp->decomp_free(rstate); | |
2291 | module_put(rcomp->owner); | |
2292 | } | |
2293 | } | |
2294 | ||
2295 | /* List of compressors. */ | |
2296 | static LIST_HEAD(compressor_list); | |
2297 | static DEFINE_SPINLOCK(compressor_list_lock); | |
2298 | ||
2299 | struct compressor_entry { | |
2300 | struct list_head list; | |
2301 | struct compressor *comp; | |
2302 | }; | |
2303 | ||
2304 | static struct compressor_entry * | |
2305 | find_comp_entry(int proto) | |
2306 | { | |
2307 | struct compressor_entry *ce; | |
1da177e4 | 2308 | |
81616c5a | 2309 | list_for_each_entry(ce, &compressor_list, list) { |
1da177e4 LT |
2310 | if (ce->comp->compress_proto == proto) |
2311 | return ce; | |
2312 | } | |
2313 | return NULL; | |
2314 | } | |
2315 | ||
2316 | /* Register a compressor */ | |
2317 | int | |
2318 | ppp_register_compressor(struct compressor *cp) | |
2319 | { | |
2320 | struct compressor_entry *ce; | |
2321 | int ret; | |
2322 | spin_lock(&compressor_list_lock); | |
2323 | ret = -EEXIST; | |
cd228d54 | 2324 | if (find_comp_entry(cp->compress_proto)) |
1da177e4 LT |
2325 | goto out; |
2326 | ret = -ENOMEM; | |
2327 | ce = kmalloc(sizeof(struct compressor_entry), GFP_ATOMIC); | |
cd228d54 | 2328 | if (!ce) |
1da177e4 LT |
2329 | goto out; |
2330 | ret = 0; | |
2331 | ce->comp = cp; | |
2332 | list_add(&ce->list, &compressor_list); | |
2333 | out: | |
2334 | spin_unlock(&compressor_list_lock); | |
2335 | return ret; | |
2336 | } | |
2337 | ||
2338 | /* Unregister a compressor */ | |
2339 | void | |
2340 | ppp_unregister_compressor(struct compressor *cp) | |
2341 | { | |
2342 | struct compressor_entry *ce; | |
2343 | ||
2344 | spin_lock(&compressor_list_lock); | |
2345 | ce = find_comp_entry(cp->compress_proto); | |
cd228d54 | 2346 | if (ce && ce->comp == cp) { |
1da177e4 LT |
2347 | list_del(&ce->list); |
2348 | kfree(ce); | |
2349 | } | |
2350 | spin_unlock(&compressor_list_lock); | |
2351 | } | |
2352 | ||
2353 | /* Find a compressor. */ | |
2354 | static struct compressor * | |
2355 | find_compressor(int type) | |
2356 | { | |
2357 | struct compressor_entry *ce; | |
2358 | struct compressor *cp = NULL; | |
2359 | ||
2360 | spin_lock(&compressor_list_lock); | |
2361 | ce = find_comp_entry(type); | |
cd228d54 | 2362 | if (ce) { |
1da177e4 LT |
2363 | cp = ce->comp; |
2364 | if (!try_module_get(cp->owner)) | |
2365 | cp = NULL; | |
2366 | } | |
2367 | spin_unlock(&compressor_list_lock); | |
2368 | return cp; | |
2369 | } | |
2370 | ||
2371 | /* | |
2372 | * Miscelleneous stuff. | |
2373 | */ | |
2374 | ||
2375 | static void | |
2376 | ppp_get_stats(struct ppp *ppp, struct ppp_stats *st) | |
2377 | { | |
2378 | struct slcompress *vj = ppp->vj; | |
2379 | ||
2380 | memset(st, 0, sizeof(*st)); | |
8c0469cd PZ |
2381 | st->p.ppp_ipackets = ppp->dev->stats.rx_packets; |
2382 | st->p.ppp_ierrors = ppp->dev->stats.rx_errors; | |
2383 | st->p.ppp_ibytes = ppp->dev->stats.rx_bytes; | |
2384 | st->p.ppp_opackets = ppp->dev->stats.tx_packets; | |
2385 | st->p.ppp_oerrors = ppp->dev->stats.tx_errors; | |
2386 | st->p.ppp_obytes = ppp->dev->stats.tx_bytes; | |
cd228d54 | 2387 | if (!vj) |
1da177e4 LT |
2388 | return; |
2389 | st->vj.vjs_packets = vj->sls_o_compressed + vj->sls_o_uncompressed; | |
2390 | st->vj.vjs_compressed = vj->sls_o_compressed; | |
2391 | st->vj.vjs_searches = vj->sls_o_searches; | |
2392 | st->vj.vjs_misses = vj->sls_o_misses; | |
2393 | st->vj.vjs_errorin = vj->sls_i_error; | |
2394 | st->vj.vjs_tossed = vj->sls_i_tossed; | |
2395 | st->vj.vjs_uncompressedin = vj->sls_i_uncompressed; | |
2396 | st->vj.vjs_compressedin = vj->sls_i_compressed; | |
2397 | } | |
2398 | ||
2399 | /* | |
2400 | * Stuff for handling the lists of ppp units and channels | |
2401 | * and for initialization. | |
2402 | */ | |
2403 | ||
2404 | /* | |
2405 | * Create a new ppp interface unit. Fails if it can't allocate memory | |
2406 | * or if there is already a unit with the requested number. | |
2407 | * unit == -1 means allocate a new number. | |
2408 | */ | |
2409 | static struct ppp * | |
2410 | ppp_create_interface(int unit, int *retp) | |
2411 | { | |
2412 | struct ppp *ppp; | |
2413 | struct net_device *dev = NULL; | |
2414 | int ret = -ENOMEM; | |
2415 | int i; | |
2416 | ||
d4274b51 | 2417 | ppp = kzalloc(sizeof(struct ppp), GFP_KERNEL); |
1da177e4 LT |
2418 | if (!ppp) |
2419 | goto out; | |
2420 | dev = alloc_netdev(0, "", ppp_setup); | |
2421 | if (!dev) | |
2422 | goto out1; | |
1da177e4 LT |
2423 | |
2424 | ppp->mru = PPP_MRU; | |
2425 | init_ppp_file(&ppp->file, INTERFACE); | |
2426 | ppp->file.hdrlen = PPP_HDRLEN - 2; /* don't count proto bytes */ | |
2427 | for (i = 0; i < NUM_NP; ++i) | |
2428 | ppp->npmode[i] = NPMODE_PASS; | |
2429 | INIT_LIST_HEAD(&ppp->channels); | |
2430 | spin_lock_init(&ppp->rlock); | |
2431 | spin_lock_init(&ppp->wlock); | |
2432 | #ifdef CONFIG_PPP_MULTILINK | |
2433 | ppp->minseq = -1; | |
2434 | skb_queue_head_init(&ppp->mrq); | |
2435 | #endif /* CONFIG_PPP_MULTILINK */ | |
2436 | ppp->dev = dev; | |
2437 | dev->priv = ppp; | |
2438 | ||
2439 | dev->hard_start_xmit = ppp_start_xmit; | |
1da177e4 LT |
2440 | dev->do_ioctl = ppp_net_ioctl; |
2441 | ||
2442 | ret = -EEXIST; | |
8ed965d6 | 2443 | mutex_lock(&all_ppp_mutex); |
1da177e4 LT |
2444 | if (unit < 0) |
2445 | unit = cardmap_find_first_free(all_ppp_units); | |
2446 | else if (cardmap_get(all_ppp_units, unit) != NULL) | |
2447 | goto out2; /* unit already exists */ | |
2448 | ||
2449 | /* Initialize the new ppp unit */ | |
2450 | ppp->file.index = unit; | |
2451 | sprintf(dev->name, "ppp%d", unit); | |
2452 | ||
2453 | ret = register_netdev(dev); | |
2454 | if (ret != 0) { | |
2455 | printk(KERN_ERR "PPP: couldn't register device %s (%d)\n", | |
2456 | dev->name, ret); | |
2457 | goto out2; | |
2458 | } | |
2459 | ||
2460 | atomic_inc(&ppp_unit_count); | |
d4274b51 PI |
2461 | ret = cardmap_set(&all_ppp_units, unit, ppp); |
2462 | if (ret != 0) | |
2463 | goto out3; | |
2464 | ||
8ed965d6 | 2465 | mutex_unlock(&all_ppp_mutex); |
1da177e4 LT |
2466 | *retp = 0; |
2467 | return ppp; | |
2468 | ||
d4274b51 PI |
2469 | out3: |
2470 | atomic_dec(&ppp_unit_count); | |
4b95ede6 | 2471 | unregister_netdev(dev); |
1da177e4 | 2472 | out2: |
8ed965d6 | 2473 | mutex_unlock(&all_ppp_mutex); |
1da177e4 LT |
2474 | free_netdev(dev); |
2475 | out1: | |
2476 | kfree(ppp); | |
2477 | out: | |
2478 | *retp = ret; | |
2479 | return NULL; | |
2480 | } | |
2481 | ||
2482 | /* | |
2483 | * Initialize a ppp_file structure. | |
2484 | */ | |
2485 | static void | |
2486 | init_ppp_file(struct ppp_file *pf, int kind) | |
2487 | { | |
2488 | pf->kind = kind; | |
2489 | skb_queue_head_init(&pf->xq); | |
2490 | skb_queue_head_init(&pf->rq); | |
2491 | atomic_set(&pf->refcnt, 1); | |
2492 | init_waitqueue_head(&pf->rwait); | |
2493 | } | |
2494 | ||
2495 | /* | |
2496 | * Take down a ppp interface unit - called when the owning file | |
2497 | * (the one that created the unit) is closed or detached. | |
2498 | */ | |
2499 | static void ppp_shutdown_interface(struct ppp *ppp) | |
2500 | { | |
8ed965d6 | 2501 | mutex_lock(&all_ppp_mutex); |
1da177e4 | 2502 | /* This will call dev_close() for us. */ |
739840d5 JC |
2503 | ppp_lock(ppp); |
2504 | if (!ppp->closing) { | |
2505 | ppp->closing = 1; | |
2506 | ppp_unlock(ppp); | |
2507 | unregister_netdev(ppp->dev); | |
2508 | } else | |
2509 | ppp_unlock(ppp); | |
2510 | ||
1da177e4 LT |
2511 | cardmap_set(&all_ppp_units, ppp->file.index, NULL); |
2512 | ppp->file.dead = 1; | |
2513 | ppp->owner = NULL; | |
2514 | wake_up_interruptible(&ppp->file.rwait); | |
8ed965d6 | 2515 | mutex_unlock(&all_ppp_mutex); |
1da177e4 LT |
2516 | } |
2517 | ||
2518 | /* | |
2519 | * Free the memory used by a ppp unit. This is only called once | |
2520 | * there are no channels connected to the unit and no file structs | |
2521 | * that reference the unit. | |
2522 | */ | |
2523 | static void ppp_destroy_interface(struct ppp *ppp) | |
2524 | { | |
2525 | atomic_dec(&ppp_unit_count); | |
2526 | ||
2527 | if (!ppp->file.dead || ppp->n_channels) { | |
2528 | /* "can't happen" */ | |
2529 | printk(KERN_ERR "ppp: destroying ppp struct %p but dead=%d " | |
2530 | "n_channels=%d !\n", ppp, ppp->file.dead, | |
2531 | ppp->n_channels); | |
2532 | return; | |
2533 | } | |
2534 | ||
2535 | ppp_ccp_closed(ppp); | |
2536 | if (ppp->vj) { | |
2537 | slhc_free(ppp->vj); | |
2538 | ppp->vj = NULL; | |
2539 | } | |
2540 | skb_queue_purge(&ppp->file.xq); | |
2541 | skb_queue_purge(&ppp->file.rq); | |
2542 | #ifdef CONFIG_PPP_MULTILINK | |
2543 | skb_queue_purge(&ppp->mrq); | |
2544 | #endif /* CONFIG_PPP_MULTILINK */ | |
2545 | #ifdef CONFIG_PPP_FILTER | |
96edf83c JJ |
2546 | kfree(ppp->pass_filter); |
2547 | ppp->pass_filter = NULL; | |
2548 | kfree(ppp->active_filter); | |
2549 | ppp->active_filter = NULL; | |
1da177e4 LT |
2550 | #endif /* CONFIG_PPP_FILTER */ |
2551 | ||
165de5b7 L |
2552 | if (ppp->xmit_pending) |
2553 | kfree_skb(ppp->xmit_pending); | |
2554 | ||
739840d5 | 2555 | free_netdev(ppp->dev); |
1da177e4 LT |
2556 | } |
2557 | ||
2558 | /* | |
2559 | * Locate an existing ppp unit. | |
8ed965d6 | 2560 | * The caller should have locked the all_ppp_mutex. |
1da177e4 LT |
2561 | */ |
2562 | static struct ppp * | |
2563 | ppp_find_unit(int unit) | |
2564 | { | |
2565 | return cardmap_get(all_ppp_units, unit); | |
2566 | } | |
2567 | ||
2568 | /* | |
2569 | * Locate an existing ppp channel. | |
2570 | * The caller should have locked the all_channels_lock. | |
2571 | * First we look in the new_channels list, then in the | |
2572 | * all_channels list. If found in the new_channels list, | |
2573 | * we move it to the all_channels list. This is for speed | |
2574 | * when we have a lot of channels in use. | |
2575 | */ | |
2576 | static struct channel * | |
2577 | ppp_find_channel(int unit) | |
2578 | { | |
2579 | struct channel *pch; | |
1da177e4 | 2580 | |
81616c5a | 2581 | list_for_each_entry(pch, &new_channels, list) { |
1da177e4 | 2582 | if (pch->file.index == unit) { |
179e0917 | 2583 | list_move(&pch->list, &all_channels); |
1da177e4 LT |
2584 | return pch; |
2585 | } | |
2586 | } | |
81616c5a | 2587 | list_for_each_entry(pch, &all_channels, list) { |
1da177e4 LT |
2588 | if (pch->file.index == unit) |
2589 | return pch; | |
2590 | } | |
2591 | return NULL; | |
2592 | } | |
2593 | ||
2594 | /* | |
2595 | * Connect a PPP channel to a PPP interface unit. | |
2596 | */ | |
2597 | static int | |
2598 | ppp_connect_channel(struct channel *pch, int unit) | |
2599 | { | |
2600 | struct ppp *ppp; | |
2601 | int ret = -ENXIO; | |
2602 | int hdrlen; | |
2603 | ||
8ed965d6 | 2604 | mutex_lock(&all_ppp_mutex); |
1da177e4 | 2605 | ppp = ppp_find_unit(unit); |
cd228d54 | 2606 | if (!ppp) |
1da177e4 LT |
2607 | goto out; |
2608 | write_lock_bh(&pch->upl); | |
2609 | ret = -EINVAL; | |
cd228d54 | 2610 | if (pch->ppp) |
1da177e4 LT |
2611 | goto outl; |
2612 | ||
2613 | ppp_lock(ppp); | |
2614 | if (pch->file.hdrlen > ppp->file.hdrlen) | |
2615 | ppp->file.hdrlen = pch->file.hdrlen; | |
2616 | hdrlen = pch->file.hdrlen + 2; /* for protocol bytes */ | |
739840d5 | 2617 | if (hdrlen > ppp->dev->hard_header_len) |
1da177e4 LT |
2618 | ppp->dev->hard_header_len = hdrlen; |
2619 | list_add_tail(&pch->clist, &ppp->channels); | |
2620 | ++ppp->n_channels; | |
2621 | pch->ppp = ppp; | |
2622 | atomic_inc(&ppp->file.refcnt); | |
2623 | ppp_unlock(ppp); | |
2624 | ret = 0; | |
2625 | ||
2626 | outl: | |
2627 | write_unlock_bh(&pch->upl); | |
2628 | out: | |
8ed965d6 | 2629 | mutex_unlock(&all_ppp_mutex); |
1da177e4 LT |
2630 | return ret; |
2631 | } | |
2632 | ||
2633 | /* | |
2634 | * Disconnect a channel from its ppp unit. | |
2635 | */ | |
2636 | static int | |
2637 | ppp_disconnect_channel(struct channel *pch) | |
2638 | { | |
2639 | struct ppp *ppp; | |
2640 | int err = -EINVAL; | |
2641 | ||
2642 | write_lock_bh(&pch->upl); | |
2643 | ppp = pch->ppp; | |
2644 | pch->ppp = NULL; | |
2645 | write_unlock_bh(&pch->upl); | |
cd228d54 | 2646 | if (ppp) { |
1da177e4 LT |
2647 | /* remove it from the ppp unit's list */ |
2648 | ppp_lock(ppp); | |
2649 | list_del(&pch->clist); | |
2650 | if (--ppp->n_channels == 0) | |
2651 | wake_up_interruptible(&ppp->file.rwait); | |
2652 | ppp_unlock(ppp); | |
2653 | if (atomic_dec_and_test(&ppp->file.refcnt)) | |
2654 | ppp_destroy_interface(ppp); | |
2655 | err = 0; | |
2656 | } | |
2657 | return err; | |
2658 | } | |
2659 | ||
2660 | /* | |
2661 | * Free up the resources used by a ppp channel. | |
2662 | */ | |
2663 | static void ppp_destroy_channel(struct channel *pch) | |
2664 | { | |
2665 | atomic_dec(&channel_count); | |
2666 | ||
2667 | if (!pch->file.dead) { | |
2668 | /* "can't happen" */ | |
2669 | printk(KERN_ERR "ppp: destroying undead channel %p !\n", | |
2670 | pch); | |
2671 | return; | |
2672 | } | |
2673 | skb_queue_purge(&pch->file.xq); | |
2674 | skb_queue_purge(&pch->file.rq); | |
2675 | kfree(pch); | |
2676 | } | |
2677 | ||
2678 | static void __exit ppp_cleanup(void) | |
2679 | { | |
2680 | /* should never happen */ | |
2681 | if (atomic_read(&ppp_unit_count) || atomic_read(&channel_count)) | |
2682 | printk(KERN_ERR "PPP: removing module but units remain!\n"); | |
2683 | cardmap_destroy(&all_ppp_units); | |
68fc4fab | 2684 | unregister_chrdev(PPP_MAJOR, "ppp"); |
9a6a2a5e | 2685 | device_destroy(ppp_class, MKDEV(PPP_MAJOR, 0)); |
56b22935 | 2686 | class_destroy(ppp_class); |
1da177e4 LT |
2687 | } |
2688 | ||
2689 | /* | |
2690 | * Cardmap implementation. | |
2691 | */ | |
2692 | static void *cardmap_get(struct cardmap *map, unsigned int nr) | |
2693 | { | |
2694 | struct cardmap *p; | |
2695 | int i; | |
2696 | ||
2697 | for (p = map; p != NULL; ) { | |
2698 | if ((i = nr >> p->shift) >= CARDMAP_WIDTH) | |
2699 | return NULL; | |
2700 | if (p->shift == 0) | |
2701 | return p->ptr[i]; | |
2702 | nr &= ~(CARDMAP_MASK << p->shift); | |
2703 | p = p->ptr[i]; | |
2704 | } | |
2705 | return NULL; | |
2706 | } | |
2707 | ||
d4274b51 | 2708 | static int cardmap_set(struct cardmap **pmap, unsigned int nr, void *ptr) |
1da177e4 LT |
2709 | { |
2710 | struct cardmap *p; | |
2711 | int i; | |
2712 | ||
2713 | p = *pmap; | |
2714 | if (p == NULL || (nr >> p->shift) >= CARDMAP_WIDTH) { | |
2715 | do { | |
2716 | /* need a new top level */ | |
d4274b51 PI |
2717 | struct cardmap *np = kzalloc(sizeof(*np), GFP_KERNEL); |
2718 | if (!np) | |
2719 | goto enomem; | |
1da177e4 LT |
2720 | np->ptr[0] = p; |
2721 | if (p != NULL) { | |
2722 | np->shift = p->shift + CARDMAP_ORDER; | |
2723 | p->parent = np; | |
2724 | } else | |
2725 | np->shift = 0; | |
2726 | p = np; | |
2727 | } while ((nr >> p->shift) >= CARDMAP_WIDTH); | |
2728 | *pmap = p; | |
2729 | } | |
2730 | while (p->shift > 0) { | |
2731 | i = (nr >> p->shift) & CARDMAP_MASK; | |
2732 | if (p->ptr[i] == NULL) { | |
d4274b51 PI |
2733 | struct cardmap *np = kzalloc(sizeof(*np), GFP_KERNEL); |
2734 | if (!np) | |
2735 | goto enomem; | |
1da177e4 LT |
2736 | np->shift = p->shift - CARDMAP_ORDER; |
2737 | np->parent = p; | |
2738 | p->ptr[i] = np; | |
2739 | } | |
2740 | if (ptr == NULL) | |
2741 | clear_bit(i, &p->inuse); | |
2742 | p = p->ptr[i]; | |
2743 | } | |
2744 | i = nr & CARDMAP_MASK; | |
2745 | p->ptr[i] = ptr; | |
2746 | if (ptr != NULL) | |
2747 | set_bit(i, &p->inuse); | |
2748 | else | |
2749 | clear_bit(i, &p->inuse); | |
d4274b51 PI |
2750 | return 0; |
2751 | enomem: | |
2752 | return -ENOMEM; | |
1da177e4 LT |
2753 | } |
2754 | ||
2755 | static unsigned int cardmap_find_first_free(struct cardmap *map) | |
2756 | { | |
2757 | struct cardmap *p; | |
2758 | unsigned int nr = 0; | |
2759 | int i; | |
2760 | ||
2761 | if ((p = map) == NULL) | |
2762 | return 0; | |
2763 | for (;;) { | |
2764 | i = find_first_zero_bit(&p->inuse, CARDMAP_WIDTH); | |
2765 | if (i >= CARDMAP_WIDTH) { | |
2766 | if (p->parent == NULL) | |
2767 | return CARDMAP_WIDTH << p->shift; | |
2768 | p = p->parent; | |
2769 | i = (nr >> p->shift) & CARDMAP_MASK; | |
2770 | set_bit(i, &p->inuse); | |
2771 | continue; | |
2772 | } | |
2773 | nr = (nr & (~CARDMAP_MASK << p->shift)) | (i << p->shift); | |
2774 | if (p->shift == 0 || p->ptr[i] == NULL) | |
2775 | return nr; | |
2776 | p = p->ptr[i]; | |
2777 | } | |
2778 | } | |
2779 | ||
2780 | static void cardmap_destroy(struct cardmap **pmap) | |
2781 | { | |
2782 | struct cardmap *p, *np; | |
2783 | int i; | |
2784 | ||
2785 | for (p = *pmap; p != NULL; p = np) { | |
2786 | if (p->shift != 0) { | |
2787 | for (i = 0; i < CARDMAP_WIDTH; ++i) | |
2788 | if (p->ptr[i] != NULL) | |
2789 | break; | |
2790 | if (i < CARDMAP_WIDTH) { | |
2791 | np = p->ptr[i]; | |
2792 | p->ptr[i] = NULL; | |
2793 | continue; | |
2794 | } | |
2795 | } | |
2796 | np = p->parent; | |
2797 | kfree(p); | |
2798 | } | |
2799 | *pmap = NULL; | |
2800 | } | |
2801 | ||
2802 | /* Module/initialization stuff */ | |
2803 | ||
2804 | module_init(ppp_init); | |
2805 | module_exit(ppp_cleanup); | |
2806 | ||
2807 | EXPORT_SYMBOL(ppp_register_channel); | |
2808 | EXPORT_SYMBOL(ppp_unregister_channel); | |
2809 | EXPORT_SYMBOL(ppp_channel_index); | |
2810 | EXPORT_SYMBOL(ppp_unit_number); | |
2811 | EXPORT_SYMBOL(ppp_input); | |
2812 | EXPORT_SYMBOL(ppp_input_error); | |
2813 | EXPORT_SYMBOL(ppp_output_wakeup); | |
2814 | EXPORT_SYMBOL(ppp_register_compressor); | |
2815 | EXPORT_SYMBOL(ppp_unregister_compressor); | |
2816 | MODULE_LICENSE("GPL"); | |
2817 | MODULE_ALIAS_CHARDEV_MAJOR(PPP_MAJOR); | |
2818 | MODULE_ALIAS("/dev/ppp"); |