Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * Generic PPP layer for Linux. | |
3 | * | |
4 | * Copyright 1999-2002 Paul Mackerras. | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or | |
7 | * modify it under the terms of the GNU General Public License | |
8 | * as published by the Free Software Foundation; either version | |
9 | * 2 of the License, or (at your option) any later version. | |
10 | * | |
11 | * The generic PPP layer handles the PPP network interfaces, the | |
12 | * /dev/ppp device, packet and VJ compression, and multilink. | |
13 | * It talks to PPP `channels' via the interface defined in | |
14 | * include/linux/ppp_channel.h. Channels provide the basic means for | |
15 | * sending and receiving PPP frames on some kind of communications | |
16 | * channel. | |
17 | * | |
18 | * Part of the code in this driver was inspired by the old async-only | |
19 | * PPP driver, written by Michael Callahan and Al Longyear, and | |
20 | * subsequently hacked by Paul Mackerras. | |
21 | * | |
22 | * ==FILEVERSION 20041108== | |
23 | */ | |
24 | ||
1da177e4 LT |
25 | #include <linux/module.h> |
26 | #include <linux/kernel.h> | |
27 | #include <linux/kmod.h> | |
28 | #include <linux/init.h> | |
29 | #include <linux/list.h> | |
7a95d267 | 30 | #include <linux/idr.h> |
1da177e4 LT |
31 | #include <linux/netdevice.h> |
32 | #include <linux/poll.h> | |
33 | #include <linux/ppp_defs.h> | |
34 | #include <linux/filter.h> | |
35 | #include <linux/if_ppp.h> | |
36 | #include <linux/ppp_channel.h> | |
37 | #include <linux/ppp-comp.h> | |
38 | #include <linux/skbuff.h> | |
39 | #include <linux/rtnetlink.h> | |
40 | #include <linux/if_arp.h> | |
41 | #include <linux/ip.h> | |
42 | #include <linux/tcp.h> | |
f2b9857e | 43 | #include <linux/smp_lock.h> |
1da177e4 | 44 | #include <linux/spinlock.h> |
1da177e4 LT |
45 | #include <linux/rwsem.h> |
46 | #include <linux/stddef.h> | |
47 | #include <linux/device.h> | |
8ed965d6 | 48 | #include <linux/mutex.h> |
1da177e4 LT |
49 | #include <net/slhc_vj.h> |
50 | #include <asm/atomic.h> | |
51 | ||
273ec51d CG |
52 | #include <linux/nsproxy.h> |
53 | #include <net/net_namespace.h> | |
54 | #include <net/netns/generic.h> | |
55 | ||
1da177e4 LT |
56 | #define PPP_VERSION "2.4.2" |
57 | ||
58 | /* | |
59 | * Network protocols we support. | |
60 | */ | |
61 | #define NP_IP 0 /* Internet Protocol V4 */ | |
62 | #define NP_IPV6 1 /* Internet Protocol V6 */ | |
63 | #define NP_IPX 2 /* IPX protocol */ | |
64 | #define NP_AT 3 /* Appletalk protocol */ | |
65 | #define NP_MPLS_UC 4 /* MPLS unicast */ | |
66 | #define NP_MPLS_MC 5 /* MPLS multicast */ | |
67 | #define NUM_NP 6 /* Number of NPs. */ | |
68 | ||
69 | #define MPHDRLEN 6 /* multilink protocol header length */ | |
70 | #define MPHDRLEN_SSN 4 /* ditto with short sequence numbers */ | |
71 | #define MIN_FRAG_SIZE 64 | |
72 | ||
73 | /* | |
74 | * An instance of /dev/ppp can be associated with either a ppp | |
75 | * interface unit or a ppp channel. In both cases, file->private_data | |
76 | * points to one of these. | |
77 | */ | |
78 | struct ppp_file { | |
79 | enum { | |
80 | INTERFACE=1, CHANNEL | |
81 | } kind; | |
82 | struct sk_buff_head xq; /* pppd transmit queue */ | |
83 | struct sk_buff_head rq; /* receive queue for pppd */ | |
84 | wait_queue_head_t rwait; /* for poll on reading /dev/ppp */ | |
85 | atomic_t refcnt; /* # refs (incl /dev/ppp attached) */ | |
86 | int hdrlen; /* space to leave for headers */ | |
87 | int index; /* interface unit / channel number */ | |
88 | int dead; /* unit/channel has been shut down */ | |
89 | }; | |
90 | ||
b385a144 | 91 | #define PF_TO_X(pf, X) container_of(pf, X, file) |
1da177e4 LT |
92 | |
93 | #define PF_TO_PPP(pf) PF_TO_X(pf, struct ppp) | |
94 | #define PF_TO_CHANNEL(pf) PF_TO_X(pf, struct channel) | |
95 | ||
1da177e4 LT |
96 | /* |
97 | * Data structure describing one ppp unit. | |
98 | * A ppp unit corresponds to a ppp network interface device | |
99 | * and represents a multilink bundle. | |
100 | * It can have 0 or more ppp channels connected to it. | |
101 | */ | |
102 | struct ppp { | |
103 | struct ppp_file file; /* stuff for read/write/poll 0 */ | |
104 | struct file *owner; /* file that owns this unit 48 */ | |
105 | struct list_head channels; /* list of attached channels 4c */ | |
106 | int n_channels; /* how many channels are attached 54 */ | |
107 | spinlock_t rlock; /* lock for receive side 58 */ | |
108 | spinlock_t wlock; /* lock for transmit side 5c */ | |
109 | int mru; /* max receive unit 60 */ | |
110 | unsigned int flags; /* control bits 64 */ | |
111 | unsigned int xstate; /* transmit state bits 68 */ | |
112 | unsigned int rstate; /* receive state bits 6c */ | |
113 | int debug; /* debug flags 70 */ | |
114 | struct slcompress *vj; /* state for VJ header compression */ | |
115 | enum NPmode npmode[NUM_NP]; /* what to do with each net proto 78 */ | |
116 | struct sk_buff *xmit_pending; /* a packet ready to go out 88 */ | |
117 | struct compressor *xcomp; /* transmit packet compressor 8c */ | |
118 | void *xc_state; /* its internal state 90 */ | |
119 | struct compressor *rcomp; /* receive decompressor 94 */ | |
120 | void *rc_state; /* its internal state 98 */ | |
121 | unsigned long last_xmit; /* jiffies when last pkt sent 9c */ | |
122 | unsigned long last_recv; /* jiffies when last pkt rcvd a0 */ | |
123 | struct net_device *dev; /* network interface device a4 */ | |
739840d5 | 124 | int closing; /* is device closing down? a8 */ |
1da177e4 LT |
125 | #ifdef CONFIG_PPP_MULTILINK |
126 | int nxchan; /* next channel to send something on */ | |
127 | u32 nxseq; /* next sequence number to send */ | |
128 | int mrru; /* MP: max reconst. receive unit */ | |
129 | u32 nextseq; /* MP: seq no of next packet */ | |
130 | u32 minseq; /* MP: min of most recent seqnos */ | |
131 | struct sk_buff_head mrq; /* MP: receive reconstruction queue */ | |
132 | #endif /* CONFIG_PPP_MULTILINK */ | |
1da177e4 LT |
133 | #ifdef CONFIG_PPP_FILTER |
134 | struct sock_filter *pass_filter; /* filter for packets to pass */ | |
135 | struct sock_filter *active_filter;/* filter for pkts to reset idle */ | |
136 | unsigned pass_len, active_len; | |
137 | #endif /* CONFIG_PPP_FILTER */ | |
273ec51d | 138 | struct net *ppp_net; /* the net we belong to */ |
1da177e4 LT |
139 | }; |
140 | ||
141 | /* | |
142 | * Bits in flags: SC_NO_TCP_CCID, SC_CCP_OPEN, SC_CCP_UP, SC_LOOP_TRAFFIC, | |
b3f9b92a MD |
143 | * SC_MULTILINK, SC_MP_SHORTSEQ, SC_MP_XSHORTSEQ, SC_COMP_TCP, SC_REJ_COMP_TCP, |
144 | * SC_MUST_COMP | |
1da177e4 LT |
145 | * Bits in rstate: SC_DECOMP_RUN, SC_DC_ERROR, SC_DC_FERROR. |
146 | * Bits in xstate: SC_COMP_RUN | |
147 | */ | |
148 | #define SC_FLAG_BITS (SC_NO_TCP_CCID|SC_CCP_OPEN|SC_CCP_UP|SC_LOOP_TRAFFIC \ | |
149 | |SC_MULTILINK|SC_MP_SHORTSEQ|SC_MP_XSHORTSEQ \ | |
b3f9b92a | 150 | |SC_COMP_TCP|SC_REJ_COMP_TCP|SC_MUST_COMP) |
1da177e4 LT |
151 | |
152 | /* | |
153 | * Private data structure for each channel. | |
154 | * This includes the data structure used for multilink. | |
155 | */ | |
156 | struct channel { | |
157 | struct ppp_file file; /* stuff for read/write/poll */ | |
158 | struct list_head list; /* link in all/new_channels list */ | |
159 | struct ppp_channel *chan; /* public channel data structure */ | |
160 | struct rw_semaphore chan_sem; /* protects `chan' during chan ioctl */ | |
161 | spinlock_t downl; /* protects `chan', file.xq dequeue */ | |
162 | struct ppp *ppp; /* ppp unit we're connected to */ | |
273ec51d | 163 | struct net *chan_net; /* the net channel belongs to */ |
1da177e4 LT |
164 | struct list_head clist; /* link in list of channels per unit */ |
165 | rwlock_t upl; /* protects `ppp' */ | |
166 | #ifdef CONFIG_PPP_MULTILINK | |
167 | u8 avail; /* flag used in multilink stuff */ | |
168 | u8 had_frag; /* >= 1 fragments have been sent */ | |
169 | u32 lastseq; /* MP: last sequence # received */ | |
170 | #endif /* CONFIG_PPP_MULTILINK */ | |
171 | }; | |
172 | ||
173 | /* | |
174 | * SMP locking issues: | |
175 | * Both the ppp.rlock and ppp.wlock locks protect the ppp.channels | |
176 | * list and the ppp.n_channels field, you need to take both locks | |
177 | * before you modify them. | |
178 | * The lock ordering is: channel.upl -> ppp.wlock -> ppp.rlock -> | |
179 | * channel.downl. | |
180 | */ | |
181 | ||
1da177e4 | 182 | static atomic_t ppp_unit_count = ATOMIC_INIT(0); |
1da177e4 LT |
183 | static atomic_t channel_count = ATOMIC_INIT(0); |
184 | ||
273ec51d CG |
185 | /* per-net private data for this module */ |
186 | static unsigned int ppp_net_id; | |
187 | struct ppp_net { | |
188 | /* units to ppp mapping */ | |
189 | struct idr units_idr; | |
190 | ||
191 | /* | |
192 | * all_ppp_mutex protects the units_idr mapping. | |
193 | * It also ensures that finding a ppp unit in the units_idr | |
194 | * map and updating its file.refcnt field is atomic. | |
195 | */ | |
196 | struct mutex all_ppp_mutex; | |
197 | ||
198 | /* channels */ | |
199 | struct list_head all_channels; | |
200 | struct list_head new_channels; | |
201 | int last_channel_index; | |
202 | ||
203 | /* | |
204 | * all_channels_lock protects all_channels and | |
205 | * last_channel_index, and the atomicity of find | |
206 | * a channel and updating its file.refcnt field. | |
207 | */ | |
208 | spinlock_t all_channels_lock; | |
209 | }; | |
210 | ||
1da177e4 LT |
211 | /* Get the PPP protocol number from a skb */ |
212 | #define PPP_PROTO(skb) (((skb)->data[0] << 8) + (skb)->data[1]) | |
213 | ||
214 | /* We limit the length of ppp->file.rq to this (arbitrary) value */ | |
215 | #define PPP_MAX_RQLEN 32 | |
216 | ||
217 | /* | |
218 | * Maximum number of multilink fragments queued up. | |
219 | * This has to be large enough to cope with the maximum latency of | |
220 | * the slowest channel relative to the others. Strictly it should | |
221 | * depend on the number of channels and their characteristics. | |
222 | */ | |
223 | #define PPP_MP_MAX_QLEN 128 | |
224 | ||
225 | /* Multilink header bits. */ | |
226 | #define B 0x80 /* this fragment begins a packet */ | |
227 | #define E 0x40 /* this fragment ends a packet */ | |
228 | ||
229 | /* Compare multilink sequence numbers (assumed to be 32 bits wide) */ | |
230 | #define seq_before(a, b) ((s32)((a) - (b)) < 0) | |
231 | #define seq_after(a, b) ((s32)((a) - (b)) > 0) | |
232 | ||
233 | /* Prototypes. */ | |
273ec51d CG |
234 | static int ppp_unattached_ioctl(struct net *net, struct ppp_file *pf, |
235 | struct file *file, unsigned int cmd, unsigned long arg); | |
1da177e4 LT |
236 | static void ppp_xmit_process(struct ppp *ppp); |
237 | static void ppp_send_frame(struct ppp *ppp, struct sk_buff *skb); | |
238 | static void ppp_push(struct ppp *ppp); | |
239 | static void ppp_channel_push(struct channel *pch); | |
240 | static void ppp_receive_frame(struct ppp *ppp, struct sk_buff *skb, | |
241 | struct channel *pch); | |
242 | static void ppp_receive_error(struct ppp *ppp); | |
243 | static void ppp_receive_nonmp_frame(struct ppp *ppp, struct sk_buff *skb); | |
244 | static struct sk_buff *ppp_decompress_frame(struct ppp *ppp, | |
245 | struct sk_buff *skb); | |
246 | #ifdef CONFIG_PPP_MULTILINK | |
247 | static void ppp_receive_mp_frame(struct ppp *ppp, struct sk_buff *skb, | |
248 | struct channel *pch); | |
249 | static void ppp_mp_insert(struct ppp *ppp, struct sk_buff *skb); | |
250 | static struct sk_buff *ppp_mp_reconstruct(struct ppp *ppp); | |
251 | static int ppp_mp_explode(struct ppp *ppp, struct sk_buff *skb); | |
252 | #endif /* CONFIG_PPP_MULTILINK */ | |
253 | static int ppp_set_compress(struct ppp *ppp, unsigned long arg); | |
254 | static void ppp_ccp_peek(struct ppp *ppp, struct sk_buff *skb, int inbound); | |
255 | static void ppp_ccp_closed(struct ppp *ppp); | |
256 | static struct compressor *find_compressor(int type); | |
257 | static void ppp_get_stats(struct ppp *ppp, struct ppp_stats *st); | |
273ec51d | 258 | static struct ppp *ppp_create_interface(struct net *net, int unit, int *retp); |
1da177e4 LT |
259 | static void init_ppp_file(struct ppp_file *pf, int kind); |
260 | static void ppp_shutdown_interface(struct ppp *ppp); | |
261 | static void ppp_destroy_interface(struct ppp *ppp); | |
273ec51d CG |
262 | static struct ppp *ppp_find_unit(struct ppp_net *pn, int unit); |
263 | static struct channel *ppp_find_channel(struct ppp_net *pn, int unit); | |
1da177e4 LT |
264 | static int ppp_connect_channel(struct channel *pch, int unit); |
265 | static int ppp_disconnect_channel(struct channel *pch); | |
266 | static void ppp_destroy_channel(struct channel *pch); | |
7a95d267 | 267 | static int unit_get(struct idr *p, void *ptr); |
85997576 | 268 | static int unit_set(struct idr *p, void *ptr, int n); |
7a95d267 CG |
269 | static void unit_put(struct idr *p, int n); |
270 | static void *unit_find(struct idr *p, int n); | |
1da177e4 | 271 | |
56b22935 | 272 | static struct class *ppp_class; |
1da177e4 | 273 | |
273ec51d CG |
274 | /* per net-namespace data */ |
275 | static inline struct ppp_net *ppp_pernet(struct net *net) | |
276 | { | |
277 | BUG_ON(!net); | |
278 | ||
279 | return net_generic(net, ppp_net_id); | |
280 | } | |
281 | ||
1da177e4 LT |
282 | /* Translates a PPP protocol number to a NP index (NP == network protocol) */ |
283 | static inline int proto_to_npindex(int proto) | |
284 | { | |
285 | switch (proto) { | |
286 | case PPP_IP: | |
287 | return NP_IP; | |
288 | case PPP_IPV6: | |
289 | return NP_IPV6; | |
290 | case PPP_IPX: | |
291 | return NP_IPX; | |
292 | case PPP_AT: | |
293 | return NP_AT; | |
294 | case PPP_MPLS_UC: | |
295 | return NP_MPLS_UC; | |
296 | case PPP_MPLS_MC: | |
297 | return NP_MPLS_MC; | |
298 | } | |
299 | return -EINVAL; | |
300 | } | |
301 | ||
302 | /* Translates an NP index into a PPP protocol number */ | |
303 | static const int npindex_to_proto[NUM_NP] = { | |
304 | PPP_IP, | |
305 | PPP_IPV6, | |
306 | PPP_IPX, | |
307 | PPP_AT, | |
308 | PPP_MPLS_UC, | |
309 | PPP_MPLS_MC, | |
310 | }; | |
6aa20a22 | 311 | |
1da177e4 LT |
312 | /* Translates an ethertype into an NP index */ |
313 | static inline int ethertype_to_npindex(int ethertype) | |
314 | { | |
315 | switch (ethertype) { | |
316 | case ETH_P_IP: | |
317 | return NP_IP; | |
318 | case ETH_P_IPV6: | |
319 | return NP_IPV6; | |
320 | case ETH_P_IPX: | |
321 | return NP_IPX; | |
322 | case ETH_P_PPPTALK: | |
323 | case ETH_P_ATALK: | |
324 | return NP_AT; | |
325 | case ETH_P_MPLS_UC: | |
326 | return NP_MPLS_UC; | |
327 | case ETH_P_MPLS_MC: | |
328 | return NP_MPLS_MC; | |
329 | } | |
330 | return -1; | |
331 | } | |
332 | ||
333 | /* Translates an NP index into an ethertype */ | |
334 | static const int npindex_to_ethertype[NUM_NP] = { | |
335 | ETH_P_IP, | |
336 | ETH_P_IPV6, | |
337 | ETH_P_IPX, | |
338 | ETH_P_PPPTALK, | |
339 | ETH_P_MPLS_UC, | |
340 | ETH_P_MPLS_MC, | |
341 | }; | |
342 | ||
343 | /* | |
344 | * Locking shorthand. | |
345 | */ | |
346 | #define ppp_xmit_lock(ppp) spin_lock_bh(&(ppp)->wlock) | |
347 | #define ppp_xmit_unlock(ppp) spin_unlock_bh(&(ppp)->wlock) | |
348 | #define ppp_recv_lock(ppp) spin_lock_bh(&(ppp)->rlock) | |
349 | #define ppp_recv_unlock(ppp) spin_unlock_bh(&(ppp)->rlock) | |
350 | #define ppp_lock(ppp) do { ppp_xmit_lock(ppp); \ | |
351 | ppp_recv_lock(ppp); } while (0) | |
352 | #define ppp_unlock(ppp) do { ppp_recv_unlock(ppp); \ | |
353 | ppp_xmit_unlock(ppp); } while (0) | |
354 | ||
355 | /* | |
356 | * /dev/ppp device routines. | |
357 | * The /dev/ppp device is used by pppd to control the ppp unit. | |
358 | * It supports the read, write, ioctl and poll functions. | |
359 | * Open instances of /dev/ppp can be in one of three states: | |
360 | * unattached, attached to a ppp unit, or attached to a ppp channel. | |
361 | */ | |
362 | static int ppp_open(struct inode *inode, struct file *file) | |
363 | { | |
f2b9857e | 364 | cycle_kernel_lock(); |
1da177e4 LT |
365 | /* |
366 | * This could (should?) be enforced by the permissions on /dev/ppp. | |
367 | */ | |
368 | if (!capable(CAP_NET_ADMIN)) | |
369 | return -EPERM; | |
370 | return 0; | |
371 | } | |
372 | ||
f3ff8a4d | 373 | static int ppp_release(struct inode *unused, struct file *file) |
1da177e4 LT |
374 | { |
375 | struct ppp_file *pf = file->private_data; | |
376 | struct ppp *ppp; | |
377 | ||
cd228d54 | 378 | if (pf) { |
1da177e4 LT |
379 | file->private_data = NULL; |
380 | if (pf->kind == INTERFACE) { | |
381 | ppp = PF_TO_PPP(pf); | |
382 | if (file == ppp->owner) | |
383 | ppp_shutdown_interface(ppp); | |
384 | } | |
385 | if (atomic_dec_and_test(&pf->refcnt)) { | |
386 | switch (pf->kind) { | |
387 | case INTERFACE: | |
388 | ppp_destroy_interface(PF_TO_PPP(pf)); | |
389 | break; | |
390 | case CHANNEL: | |
391 | ppp_destroy_channel(PF_TO_CHANNEL(pf)); | |
392 | break; | |
393 | } | |
394 | } | |
395 | } | |
396 | return 0; | |
397 | } | |
398 | ||
399 | static ssize_t ppp_read(struct file *file, char __user *buf, | |
400 | size_t count, loff_t *ppos) | |
401 | { | |
402 | struct ppp_file *pf = file->private_data; | |
403 | DECLARE_WAITQUEUE(wait, current); | |
404 | ssize_t ret; | |
405 | struct sk_buff *skb = NULL; | |
406 | ||
407 | ret = count; | |
408 | ||
cd228d54 | 409 | if (!pf) |
1da177e4 LT |
410 | return -ENXIO; |
411 | add_wait_queue(&pf->rwait, &wait); | |
412 | for (;;) { | |
413 | set_current_state(TASK_INTERRUPTIBLE); | |
414 | skb = skb_dequeue(&pf->rq); | |
415 | if (skb) | |
416 | break; | |
417 | ret = 0; | |
418 | if (pf->dead) | |
419 | break; | |
420 | if (pf->kind == INTERFACE) { | |
421 | /* | |
422 | * Return 0 (EOF) on an interface that has no | |
423 | * channels connected, unless it is looping | |
424 | * network traffic (demand mode). | |
425 | */ | |
426 | struct ppp *ppp = PF_TO_PPP(pf); | |
427 | if (ppp->n_channels == 0 | |
428 | && (ppp->flags & SC_LOOP_TRAFFIC) == 0) | |
429 | break; | |
430 | } | |
431 | ret = -EAGAIN; | |
432 | if (file->f_flags & O_NONBLOCK) | |
433 | break; | |
434 | ret = -ERESTARTSYS; | |
435 | if (signal_pending(current)) | |
436 | break; | |
437 | schedule(); | |
438 | } | |
439 | set_current_state(TASK_RUNNING); | |
440 | remove_wait_queue(&pf->rwait, &wait); | |
441 | ||
cd228d54 | 442 | if (!skb) |
1da177e4 LT |
443 | goto out; |
444 | ||
445 | ret = -EOVERFLOW; | |
446 | if (skb->len > count) | |
447 | goto outf; | |
448 | ret = -EFAULT; | |
449 | if (copy_to_user(buf, skb->data, skb->len)) | |
450 | goto outf; | |
451 | ret = skb->len; | |
452 | ||
453 | outf: | |
454 | kfree_skb(skb); | |
455 | out: | |
456 | return ret; | |
457 | } | |
458 | ||
459 | static ssize_t ppp_write(struct file *file, const char __user *buf, | |
460 | size_t count, loff_t *ppos) | |
461 | { | |
462 | struct ppp_file *pf = file->private_data; | |
463 | struct sk_buff *skb; | |
464 | ssize_t ret; | |
465 | ||
cd228d54 | 466 | if (!pf) |
1da177e4 LT |
467 | return -ENXIO; |
468 | ret = -ENOMEM; | |
469 | skb = alloc_skb(count + pf->hdrlen, GFP_KERNEL); | |
cd228d54 | 470 | if (!skb) |
1da177e4 LT |
471 | goto out; |
472 | skb_reserve(skb, pf->hdrlen); | |
473 | ret = -EFAULT; | |
474 | if (copy_from_user(skb_put(skb, count), buf, count)) { | |
475 | kfree_skb(skb); | |
476 | goto out; | |
477 | } | |
478 | ||
479 | skb_queue_tail(&pf->xq, skb); | |
480 | ||
481 | switch (pf->kind) { | |
482 | case INTERFACE: | |
483 | ppp_xmit_process(PF_TO_PPP(pf)); | |
484 | break; | |
485 | case CHANNEL: | |
486 | ppp_channel_push(PF_TO_CHANNEL(pf)); | |
487 | break; | |
488 | } | |
489 | ||
490 | ret = count; | |
491 | ||
492 | out: | |
493 | return ret; | |
494 | } | |
495 | ||
496 | /* No kernel lock - fine */ | |
497 | static unsigned int ppp_poll(struct file *file, poll_table *wait) | |
498 | { | |
499 | struct ppp_file *pf = file->private_data; | |
500 | unsigned int mask; | |
501 | ||
cd228d54 | 502 | if (!pf) |
1da177e4 LT |
503 | return 0; |
504 | poll_wait(file, &pf->rwait, wait); | |
505 | mask = POLLOUT | POLLWRNORM; | |
cd228d54 | 506 | if (skb_peek(&pf->rq)) |
1da177e4 LT |
507 | mask |= POLLIN | POLLRDNORM; |
508 | if (pf->dead) | |
509 | mask |= POLLHUP; | |
510 | else if (pf->kind == INTERFACE) { | |
511 | /* see comment in ppp_read */ | |
512 | struct ppp *ppp = PF_TO_PPP(pf); | |
513 | if (ppp->n_channels == 0 | |
514 | && (ppp->flags & SC_LOOP_TRAFFIC) == 0) | |
515 | mask |= POLLIN | POLLRDNORM; | |
516 | } | |
517 | ||
518 | return mask; | |
519 | } | |
520 | ||
521 | #ifdef CONFIG_PPP_FILTER | |
522 | static int get_filter(void __user *arg, struct sock_filter **p) | |
523 | { | |
524 | struct sock_fprog uprog; | |
525 | struct sock_filter *code = NULL; | |
526 | int len, err; | |
527 | ||
528 | if (copy_from_user(&uprog, arg, sizeof(uprog))) | |
529 | return -EFAULT; | |
530 | ||
1da177e4 LT |
531 | if (!uprog.len) { |
532 | *p = NULL; | |
533 | return 0; | |
534 | } | |
535 | ||
536 | len = uprog.len * sizeof(struct sock_filter); | |
537 | code = kmalloc(len, GFP_KERNEL); | |
538 | if (code == NULL) | |
539 | return -ENOMEM; | |
540 | ||
541 | if (copy_from_user(code, uprog.filter, len)) { | |
542 | kfree(code); | |
543 | return -EFAULT; | |
544 | } | |
545 | ||
546 | err = sk_chk_filter(code, uprog.len); | |
547 | if (err) { | |
548 | kfree(code); | |
549 | return err; | |
550 | } | |
551 | ||
552 | *p = code; | |
553 | return uprog.len; | |
554 | } | |
555 | #endif /* CONFIG_PPP_FILTER */ | |
556 | ||
f3ff8a4d | 557 | static long ppp_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
1da177e4 LT |
558 | { |
559 | struct ppp_file *pf = file->private_data; | |
560 | struct ppp *ppp; | |
561 | int err = -EFAULT, val, val2, i; | |
562 | struct ppp_idle idle; | |
563 | struct npioctl npi; | |
564 | int unit, cflags; | |
565 | struct slcompress *vj; | |
566 | void __user *argp = (void __user *)arg; | |
567 | int __user *p = argp; | |
568 | ||
cd228d54 | 569 | if (!pf) |
273ec51d CG |
570 | return ppp_unattached_ioctl(current->nsproxy->net_ns, |
571 | pf, file, cmd, arg); | |
1da177e4 LT |
572 | |
573 | if (cmd == PPPIOCDETACH) { | |
574 | /* | |
575 | * We have to be careful here... if the file descriptor | |
576 | * has been dup'd, we could have another process in the | |
577 | * middle of a poll using the same file *, so we had | |
578 | * better not free the interface data structures - | |
579 | * instead we fail the ioctl. Even in this case, we | |
580 | * shut down the interface if we are the owner of it. | |
581 | * Actually, we should get rid of PPPIOCDETACH, userland | |
582 | * (i.e. pppd) could achieve the same effect by closing | |
583 | * this fd and reopening /dev/ppp. | |
584 | */ | |
585 | err = -EINVAL; | |
f3ff8a4d | 586 | lock_kernel(); |
1da177e4 LT |
587 | if (pf->kind == INTERFACE) { |
588 | ppp = PF_TO_PPP(pf); | |
589 | if (file == ppp->owner) | |
590 | ppp_shutdown_interface(ppp); | |
591 | } | |
516e0cc5 | 592 | if (atomic_long_read(&file->f_count) <= 2) { |
f3ff8a4d | 593 | ppp_release(NULL, file); |
1da177e4 LT |
594 | err = 0; |
595 | } else | |
516e0cc5 AV |
596 | printk(KERN_DEBUG "PPPIOCDETACH file->f_count=%ld\n", |
597 | atomic_long_read(&file->f_count)); | |
f3ff8a4d | 598 | unlock_kernel(); |
1da177e4 LT |
599 | return err; |
600 | } | |
601 | ||
602 | if (pf->kind == CHANNEL) { | |
f3ff8a4d | 603 | struct channel *pch; |
1da177e4 LT |
604 | struct ppp_channel *chan; |
605 | ||
f3ff8a4d AC |
606 | lock_kernel(); |
607 | pch = PF_TO_CHANNEL(pf); | |
608 | ||
1da177e4 LT |
609 | switch (cmd) { |
610 | case PPPIOCCONNECT: | |
611 | if (get_user(unit, p)) | |
612 | break; | |
613 | err = ppp_connect_channel(pch, unit); | |
614 | break; | |
615 | ||
616 | case PPPIOCDISCONN: | |
617 | err = ppp_disconnect_channel(pch); | |
618 | break; | |
619 | ||
620 | default: | |
621 | down_read(&pch->chan_sem); | |
622 | chan = pch->chan; | |
623 | err = -ENOTTY; | |
624 | if (chan && chan->ops->ioctl) | |
625 | err = chan->ops->ioctl(chan, cmd, arg); | |
626 | up_read(&pch->chan_sem); | |
627 | } | |
f3ff8a4d | 628 | unlock_kernel(); |
1da177e4 LT |
629 | return err; |
630 | } | |
631 | ||
632 | if (pf->kind != INTERFACE) { | |
633 | /* can't happen */ | |
634 | printk(KERN_ERR "PPP: not interface or channel??\n"); | |
635 | return -EINVAL; | |
636 | } | |
637 | ||
f3ff8a4d | 638 | lock_kernel(); |
1da177e4 LT |
639 | ppp = PF_TO_PPP(pf); |
640 | switch (cmd) { | |
641 | case PPPIOCSMRU: | |
642 | if (get_user(val, p)) | |
643 | break; | |
644 | ppp->mru = val; | |
645 | err = 0; | |
646 | break; | |
647 | ||
648 | case PPPIOCSFLAGS: | |
649 | if (get_user(val, p)) | |
650 | break; | |
651 | ppp_lock(ppp); | |
652 | cflags = ppp->flags & ~val; | |
653 | ppp->flags = val & SC_FLAG_BITS; | |
654 | ppp_unlock(ppp); | |
655 | if (cflags & SC_CCP_OPEN) | |
656 | ppp_ccp_closed(ppp); | |
657 | err = 0; | |
658 | break; | |
659 | ||
660 | case PPPIOCGFLAGS: | |
661 | val = ppp->flags | ppp->xstate | ppp->rstate; | |
662 | if (put_user(val, p)) | |
663 | break; | |
664 | err = 0; | |
665 | break; | |
666 | ||
667 | case PPPIOCSCOMPRESS: | |
668 | err = ppp_set_compress(ppp, arg); | |
669 | break; | |
670 | ||
671 | case PPPIOCGUNIT: | |
672 | if (put_user(ppp->file.index, p)) | |
673 | break; | |
674 | err = 0; | |
675 | break; | |
676 | ||
677 | case PPPIOCSDEBUG: | |
678 | if (get_user(val, p)) | |
679 | break; | |
680 | ppp->debug = val; | |
681 | err = 0; | |
682 | break; | |
683 | ||
684 | case PPPIOCGDEBUG: | |
685 | if (put_user(ppp->debug, p)) | |
686 | break; | |
687 | err = 0; | |
688 | break; | |
689 | ||
690 | case PPPIOCGIDLE: | |
691 | idle.xmit_idle = (jiffies - ppp->last_xmit) / HZ; | |
692 | idle.recv_idle = (jiffies - ppp->last_recv) / HZ; | |
693 | if (copy_to_user(argp, &idle, sizeof(idle))) | |
694 | break; | |
695 | err = 0; | |
696 | break; | |
697 | ||
698 | case PPPIOCSMAXCID: | |
699 | if (get_user(val, p)) | |
700 | break; | |
701 | val2 = 15; | |
702 | if ((val >> 16) != 0) { | |
703 | val2 = val >> 16; | |
704 | val &= 0xffff; | |
705 | } | |
706 | vj = slhc_init(val2+1, val+1); | |
cd228d54 | 707 | if (!vj) { |
1da177e4 LT |
708 | printk(KERN_ERR "PPP: no memory (VJ compressor)\n"); |
709 | err = -ENOMEM; | |
710 | break; | |
711 | } | |
712 | ppp_lock(ppp); | |
cd228d54 | 713 | if (ppp->vj) |
1da177e4 LT |
714 | slhc_free(ppp->vj); |
715 | ppp->vj = vj; | |
716 | ppp_unlock(ppp); | |
717 | err = 0; | |
718 | break; | |
719 | ||
720 | case PPPIOCGNPMODE: | |
721 | case PPPIOCSNPMODE: | |
722 | if (copy_from_user(&npi, argp, sizeof(npi))) | |
723 | break; | |
724 | err = proto_to_npindex(npi.protocol); | |
725 | if (err < 0) | |
726 | break; | |
727 | i = err; | |
728 | if (cmd == PPPIOCGNPMODE) { | |
729 | err = -EFAULT; | |
730 | npi.mode = ppp->npmode[i]; | |
731 | if (copy_to_user(argp, &npi, sizeof(npi))) | |
732 | break; | |
733 | } else { | |
734 | ppp->npmode[i] = npi.mode; | |
735 | /* we may be able to transmit more packets now (??) */ | |
736 | netif_wake_queue(ppp->dev); | |
737 | } | |
738 | err = 0; | |
739 | break; | |
740 | ||
741 | #ifdef CONFIG_PPP_FILTER | |
742 | case PPPIOCSPASS: | |
743 | { | |
744 | struct sock_filter *code; | |
745 | err = get_filter(argp, &code); | |
746 | if (err >= 0) { | |
747 | ppp_lock(ppp); | |
748 | kfree(ppp->pass_filter); | |
749 | ppp->pass_filter = code; | |
750 | ppp->pass_len = err; | |
751 | ppp_unlock(ppp); | |
752 | err = 0; | |
753 | } | |
754 | break; | |
755 | } | |
756 | case PPPIOCSACTIVE: | |
757 | { | |
758 | struct sock_filter *code; | |
759 | err = get_filter(argp, &code); | |
760 | if (err >= 0) { | |
761 | ppp_lock(ppp); | |
762 | kfree(ppp->active_filter); | |
763 | ppp->active_filter = code; | |
764 | ppp->active_len = err; | |
765 | ppp_unlock(ppp); | |
766 | err = 0; | |
767 | } | |
768 | break; | |
769 | } | |
770 | #endif /* CONFIG_PPP_FILTER */ | |
771 | ||
772 | #ifdef CONFIG_PPP_MULTILINK | |
773 | case PPPIOCSMRRU: | |
774 | if (get_user(val, p)) | |
775 | break; | |
776 | ppp_recv_lock(ppp); | |
777 | ppp->mrru = val; | |
778 | ppp_recv_unlock(ppp); | |
779 | err = 0; | |
780 | break; | |
781 | #endif /* CONFIG_PPP_MULTILINK */ | |
782 | ||
783 | default: | |
784 | err = -ENOTTY; | |
785 | } | |
f3ff8a4d | 786 | unlock_kernel(); |
1da177e4 LT |
787 | return err; |
788 | } | |
789 | ||
273ec51d CG |
790 | static int ppp_unattached_ioctl(struct net *net, struct ppp_file *pf, |
791 | struct file *file, unsigned int cmd, unsigned long arg) | |
1da177e4 LT |
792 | { |
793 | int unit, err = -EFAULT; | |
794 | struct ppp *ppp; | |
795 | struct channel *chan; | |
273ec51d | 796 | struct ppp_net *pn; |
1da177e4 LT |
797 | int __user *p = (int __user *)arg; |
798 | ||
f3ff8a4d | 799 | lock_kernel(); |
1da177e4 LT |
800 | switch (cmd) { |
801 | case PPPIOCNEWUNIT: | |
802 | /* Create a new ppp unit */ | |
803 | if (get_user(unit, p)) | |
804 | break; | |
273ec51d | 805 | ppp = ppp_create_interface(net, unit, &err); |
cd228d54 | 806 | if (!ppp) |
1da177e4 LT |
807 | break; |
808 | file->private_data = &ppp->file; | |
809 | ppp->owner = file; | |
810 | err = -EFAULT; | |
811 | if (put_user(ppp->file.index, p)) | |
812 | break; | |
813 | err = 0; | |
814 | break; | |
815 | ||
816 | case PPPIOCATTACH: | |
817 | /* Attach to an existing ppp unit */ | |
818 | if (get_user(unit, p)) | |
819 | break; | |
1da177e4 | 820 | err = -ENXIO; |
273ec51d CG |
821 | pn = ppp_pernet(net); |
822 | mutex_lock(&pn->all_ppp_mutex); | |
823 | ppp = ppp_find_unit(pn, unit); | |
cd228d54 | 824 | if (ppp) { |
1da177e4 LT |
825 | atomic_inc(&ppp->file.refcnt); |
826 | file->private_data = &ppp->file; | |
827 | err = 0; | |
828 | } | |
273ec51d | 829 | mutex_unlock(&pn->all_ppp_mutex); |
1da177e4 LT |
830 | break; |
831 | ||
832 | case PPPIOCATTCHAN: | |
833 | if (get_user(unit, p)) | |
834 | break; | |
1da177e4 | 835 | err = -ENXIO; |
273ec51d CG |
836 | pn = ppp_pernet(net); |
837 | spin_lock_bh(&pn->all_channels_lock); | |
838 | chan = ppp_find_channel(pn, unit); | |
cd228d54 | 839 | if (chan) { |
1da177e4 LT |
840 | atomic_inc(&chan->file.refcnt); |
841 | file->private_data = &chan->file; | |
842 | err = 0; | |
843 | } | |
273ec51d | 844 | spin_unlock_bh(&pn->all_channels_lock); |
1da177e4 LT |
845 | break; |
846 | ||
847 | default: | |
848 | err = -ENOTTY; | |
849 | } | |
f3ff8a4d | 850 | unlock_kernel(); |
1da177e4 LT |
851 | return err; |
852 | } | |
853 | ||
d54b1fdb | 854 | static const struct file_operations ppp_device_fops = { |
1da177e4 LT |
855 | .owner = THIS_MODULE, |
856 | .read = ppp_read, | |
857 | .write = ppp_write, | |
858 | .poll = ppp_poll, | |
f3ff8a4d | 859 | .unlocked_ioctl = ppp_ioctl, |
1da177e4 LT |
860 | .open = ppp_open, |
861 | .release = ppp_release | |
862 | }; | |
863 | ||
273ec51d CG |
864 | static __net_init int ppp_init_net(struct net *net) |
865 | { | |
866 | struct ppp_net *pn; | |
867 | int err; | |
868 | ||
869 | pn = kzalloc(sizeof(*pn), GFP_KERNEL); | |
870 | if (!pn) | |
871 | return -ENOMEM; | |
872 | ||
873 | idr_init(&pn->units_idr); | |
874 | mutex_init(&pn->all_ppp_mutex); | |
875 | ||
876 | INIT_LIST_HEAD(&pn->all_channels); | |
877 | INIT_LIST_HEAD(&pn->new_channels); | |
878 | ||
879 | spin_lock_init(&pn->all_channels_lock); | |
880 | ||
881 | err = net_assign_generic(net, ppp_net_id, pn); | |
882 | if (err) { | |
883 | kfree(pn); | |
884 | return err; | |
885 | } | |
886 | ||
887 | return 0; | |
888 | } | |
889 | ||
890 | static __net_exit void ppp_exit_net(struct net *net) | |
891 | { | |
892 | struct ppp_net *pn; | |
893 | ||
894 | pn = net_generic(net, ppp_net_id); | |
895 | idr_destroy(&pn->units_idr); | |
896 | /* | |
897 | * if someone has cached our net then | |
898 | * further net_generic call will return NULL | |
899 | */ | |
900 | net_assign_generic(net, ppp_net_id, NULL); | |
901 | kfree(pn); | |
902 | } | |
903 | ||
904 | static __net_initdata struct pernet_operations ppp_net_ops = { | |
905 | .init = ppp_init_net, | |
906 | .exit = ppp_exit_net, | |
907 | }; | |
908 | ||
1da177e4 LT |
909 | #define PPP_MAJOR 108 |
910 | ||
911 | /* Called at boot time if ppp is compiled into the kernel, | |
912 | or at module load time (from init_module) if compiled as a module. */ | |
913 | static int __init ppp_init(void) | |
914 | { | |
915 | int err; | |
916 | ||
917 | printk(KERN_INFO "PPP generic driver version " PPP_VERSION "\n"); | |
273ec51d CG |
918 | |
919 | err = register_pernet_gen_device(&ppp_net_id, &ppp_net_ops); | |
920 | if (err) { | |
921 | printk(KERN_ERR "failed to register PPP pernet device (%d)\n", err); | |
922 | goto out; | |
1da177e4 LT |
923 | } |
924 | ||
273ec51d CG |
925 | err = register_chrdev(PPP_MAJOR, "ppp", &ppp_device_fops); |
926 | if (err) { | |
1da177e4 | 927 | printk(KERN_ERR "failed to register PPP device (%d)\n", err); |
273ec51d CG |
928 | goto out_net; |
929 | } | |
930 | ||
931 | ppp_class = class_create(THIS_MODULE, "ppp"); | |
932 | if (IS_ERR(ppp_class)) { | |
933 | err = PTR_ERR(ppp_class); | |
934 | goto out_chrdev; | |
935 | } | |
936 | ||
937 | /* not a big deal if we fail here :-) */ | |
938 | device_create(ppp_class, NULL, MKDEV(PPP_MAJOR, 0), NULL, "ppp"); | |
939 | ||
940 | return 0; | |
1da177e4 | 941 | |
1da177e4 LT |
942 | out_chrdev: |
943 | unregister_chrdev(PPP_MAJOR, "ppp"); | |
273ec51d CG |
944 | out_net: |
945 | unregister_pernet_gen_device(ppp_net_id, &ppp_net_ops); | |
946 | out: | |
947 | return err; | |
1da177e4 LT |
948 | } |
949 | ||
950 | /* | |
951 | * Network interface unit routines. | |
952 | */ | |
953 | static int | |
954 | ppp_start_xmit(struct sk_buff *skb, struct net_device *dev) | |
955 | { | |
c8019bf3 | 956 | struct ppp *ppp = netdev_priv(dev); |
1da177e4 LT |
957 | int npi, proto; |
958 | unsigned char *pp; | |
959 | ||
960 | npi = ethertype_to_npindex(ntohs(skb->protocol)); | |
961 | if (npi < 0) | |
962 | goto outf; | |
963 | ||
964 | /* Drop, accept or reject the packet */ | |
965 | switch (ppp->npmode[npi]) { | |
966 | case NPMODE_PASS: | |
967 | break; | |
968 | case NPMODE_QUEUE: | |
969 | /* it would be nice to have a way to tell the network | |
970 | system to queue this one up for later. */ | |
971 | goto outf; | |
972 | case NPMODE_DROP: | |
973 | case NPMODE_ERROR: | |
974 | goto outf; | |
975 | } | |
976 | ||
977 | /* Put the 2-byte PPP protocol number on the front, | |
978 | making sure there is room for the address and control fields. */ | |
7b797d5b HX |
979 | if (skb_cow_head(skb, PPP_HDRLEN)) |
980 | goto outf; | |
981 | ||
1da177e4 LT |
982 | pp = skb_push(skb, 2); |
983 | proto = npindex_to_proto[npi]; | |
984 | pp[0] = proto >> 8; | |
985 | pp[1] = proto; | |
986 | ||
987 | netif_stop_queue(dev); | |
988 | skb_queue_tail(&ppp->file.xq, skb); | |
989 | ppp_xmit_process(ppp); | |
990 | return 0; | |
991 | ||
992 | outf: | |
993 | kfree_skb(skb); | |
8c0469cd | 994 | ++ppp->dev->stats.tx_dropped; |
1da177e4 LT |
995 | return 0; |
996 | } | |
997 | ||
1da177e4 LT |
998 | static int |
999 | ppp_net_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) | |
1000 | { | |
c8019bf3 | 1001 | struct ppp *ppp = netdev_priv(dev); |
1da177e4 LT |
1002 | int err = -EFAULT; |
1003 | void __user *addr = (void __user *) ifr->ifr_ifru.ifru_data; | |
1004 | struct ppp_stats stats; | |
1005 | struct ppp_comp_stats cstats; | |
1006 | char *vers; | |
1007 | ||
1008 | switch (cmd) { | |
1009 | case SIOCGPPPSTATS: | |
1010 | ppp_get_stats(ppp, &stats); | |
1011 | if (copy_to_user(addr, &stats, sizeof(stats))) | |
1012 | break; | |
1013 | err = 0; | |
1014 | break; | |
1015 | ||
1016 | case SIOCGPPPCSTATS: | |
1017 | memset(&cstats, 0, sizeof(cstats)); | |
cd228d54 | 1018 | if (ppp->xc_state) |
1da177e4 | 1019 | ppp->xcomp->comp_stat(ppp->xc_state, &cstats.c); |
cd228d54 | 1020 | if (ppp->rc_state) |
1da177e4 LT |
1021 | ppp->rcomp->decomp_stat(ppp->rc_state, &cstats.d); |
1022 | if (copy_to_user(addr, &cstats, sizeof(cstats))) | |
1023 | break; | |
1024 | err = 0; | |
1025 | break; | |
1026 | ||
1027 | case SIOCGPPPVER: | |
1028 | vers = PPP_VERSION; | |
1029 | if (copy_to_user(addr, vers, strlen(vers) + 1)) | |
1030 | break; | |
1031 | err = 0; | |
1032 | break; | |
1033 | ||
1034 | default: | |
1035 | err = -EINVAL; | |
1036 | } | |
1037 | ||
1038 | return err; | |
1039 | } | |
1040 | ||
52256cfc | 1041 | static const struct net_device_ops ppp_netdev_ops = { |
00829823 SH |
1042 | .ndo_start_xmit = ppp_start_xmit, |
1043 | .ndo_do_ioctl = ppp_net_ioctl, | |
52256cfc SH |
1044 | }; |
1045 | ||
1da177e4 LT |
1046 | static void ppp_setup(struct net_device *dev) |
1047 | { | |
52256cfc | 1048 | dev->netdev_ops = &ppp_netdev_ops; |
1da177e4 LT |
1049 | dev->hard_header_len = PPP_HDRLEN; |
1050 | dev->mtu = PPP_MTU; | |
1051 | dev->addr_len = 0; | |
1052 | dev->tx_queue_len = 3; | |
1053 | dev->type = ARPHRD_PPP; | |
1054 | dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST; | |
273ec51d | 1055 | dev->features |= NETIF_F_NETNS_LOCAL; |
1da177e4 LT |
1056 | } |
1057 | ||
1058 | /* | |
1059 | * Transmit-side routines. | |
1060 | */ | |
1061 | ||
1062 | /* | |
1063 | * Called to do any work queued up on the transmit side | |
1064 | * that can now be done. | |
1065 | */ | |
1066 | static void | |
1067 | ppp_xmit_process(struct ppp *ppp) | |
1068 | { | |
1069 | struct sk_buff *skb; | |
1070 | ||
1071 | ppp_xmit_lock(ppp); | |
739840d5 | 1072 | if (!ppp->closing) { |
1da177e4 | 1073 | ppp_push(ppp); |
cd228d54 JP |
1074 | while (!ppp->xmit_pending |
1075 | && (skb = skb_dequeue(&ppp->file.xq))) | |
1da177e4 LT |
1076 | ppp_send_frame(ppp, skb); |
1077 | /* If there's no work left to do, tell the core net | |
1078 | code that we can accept some more. */ | |
cd228d54 | 1079 | if (!ppp->xmit_pending && !skb_peek(&ppp->file.xq)) |
1da177e4 LT |
1080 | netif_wake_queue(ppp->dev); |
1081 | } | |
1082 | ppp_xmit_unlock(ppp); | |
1083 | } | |
1084 | ||
b3f9b92a MD |
1085 | static inline struct sk_buff * |
1086 | pad_compress_skb(struct ppp *ppp, struct sk_buff *skb) | |
1087 | { | |
1088 | struct sk_buff *new_skb; | |
1089 | int len; | |
1090 | int new_skb_size = ppp->dev->mtu + | |
1091 | ppp->xcomp->comp_extra + ppp->dev->hard_header_len; | |
1092 | int compressor_skb_size = ppp->dev->mtu + | |
1093 | ppp->xcomp->comp_extra + PPP_HDRLEN; | |
1094 | new_skb = alloc_skb(new_skb_size, GFP_ATOMIC); | |
1095 | if (!new_skb) { | |
1096 | if (net_ratelimit()) | |
1097 | printk(KERN_ERR "PPP: no memory (comp pkt)\n"); | |
1098 | return NULL; | |
1099 | } | |
1100 | if (ppp->dev->hard_header_len > PPP_HDRLEN) | |
1101 | skb_reserve(new_skb, | |
1102 | ppp->dev->hard_header_len - PPP_HDRLEN); | |
1103 | ||
1104 | /* compressor still expects A/C bytes in hdr */ | |
1105 | len = ppp->xcomp->compress(ppp->xc_state, skb->data - 2, | |
1106 | new_skb->data, skb->len + 2, | |
1107 | compressor_skb_size); | |
1108 | if (len > 0 && (ppp->flags & SC_CCP_UP)) { | |
1109 | kfree_skb(skb); | |
1110 | skb = new_skb; | |
1111 | skb_put(skb, len); | |
1112 | skb_pull(skb, 2); /* pull off A/C bytes */ | |
1113 | } else if (len == 0) { | |
1114 | /* didn't compress, or CCP not up yet */ | |
1115 | kfree_skb(new_skb); | |
1116 | new_skb = skb; | |
1117 | } else { | |
1118 | /* | |
1119 | * (len < 0) | |
1120 | * MPPE requires that we do not send unencrypted | |
1121 | * frames. The compressor will return -1 if we | |
1122 | * should drop the frame. We cannot simply test | |
1123 | * the compress_proto because MPPE and MPPC share | |
1124 | * the same number. | |
1125 | */ | |
1126 | if (net_ratelimit()) | |
1127 | printk(KERN_ERR "ppp: compressor dropped pkt\n"); | |
1128 | kfree_skb(skb); | |
1129 | kfree_skb(new_skb); | |
1130 | new_skb = NULL; | |
1131 | } | |
1132 | return new_skb; | |
1133 | } | |
1134 | ||
1da177e4 LT |
1135 | /* |
1136 | * Compress and send a frame. | |
1137 | * The caller should have locked the xmit path, | |
1138 | * and xmit_pending should be 0. | |
1139 | */ | |
1140 | static void | |
1141 | ppp_send_frame(struct ppp *ppp, struct sk_buff *skb) | |
1142 | { | |
1143 | int proto = PPP_PROTO(skb); | |
1144 | struct sk_buff *new_skb; | |
1145 | int len; | |
1146 | unsigned char *cp; | |
1147 | ||
1148 | if (proto < 0x8000) { | |
1149 | #ifdef CONFIG_PPP_FILTER | |
1150 | /* check if we should pass this packet */ | |
1151 | /* the filter instructions are constructed assuming | |
1152 | a four-byte PPP header on each packet */ | |
1153 | *skb_push(skb, 2) = 1; | |
1154 | if (ppp->pass_filter | |
1155 | && sk_run_filter(skb, ppp->pass_filter, | |
1156 | ppp->pass_len) == 0) { | |
1157 | if (ppp->debug & 1) | |
1158 | printk(KERN_DEBUG "PPP: outbound frame not passed\n"); | |
1159 | kfree_skb(skb); | |
1160 | return; | |
1161 | } | |
1162 | /* if this packet passes the active filter, record the time */ | |
1163 | if (!(ppp->active_filter | |
1164 | && sk_run_filter(skb, ppp->active_filter, | |
1165 | ppp->active_len) == 0)) | |
1166 | ppp->last_xmit = jiffies; | |
1167 | skb_pull(skb, 2); | |
1168 | #else | |
1169 | /* for data packets, record the time */ | |
1170 | ppp->last_xmit = jiffies; | |
1171 | #endif /* CONFIG_PPP_FILTER */ | |
1172 | } | |
1173 | ||
8c0469cd PZ |
1174 | ++ppp->dev->stats.tx_packets; |
1175 | ppp->dev->stats.tx_bytes += skb->len - 2; | |
1da177e4 LT |
1176 | |
1177 | switch (proto) { | |
1178 | case PPP_IP: | |
cd228d54 | 1179 | if (!ppp->vj || (ppp->flags & SC_COMP_TCP) == 0) |
1da177e4 LT |
1180 | break; |
1181 | /* try to do VJ TCP header compression */ | |
1182 | new_skb = alloc_skb(skb->len + ppp->dev->hard_header_len - 2, | |
1183 | GFP_ATOMIC); | |
cd228d54 | 1184 | if (!new_skb) { |
1da177e4 LT |
1185 | printk(KERN_ERR "PPP: no memory (VJ comp pkt)\n"); |
1186 | goto drop; | |
1187 | } | |
1188 | skb_reserve(new_skb, ppp->dev->hard_header_len - 2); | |
1189 | cp = skb->data + 2; | |
1190 | len = slhc_compress(ppp->vj, cp, skb->len - 2, | |
1191 | new_skb->data + 2, &cp, | |
1192 | !(ppp->flags & SC_NO_TCP_CCID)); | |
1193 | if (cp == skb->data + 2) { | |
1194 | /* didn't compress */ | |
1195 | kfree_skb(new_skb); | |
1196 | } else { | |
1197 | if (cp[0] & SL_TYPE_COMPRESSED_TCP) { | |
1198 | proto = PPP_VJC_COMP; | |
1199 | cp[0] &= ~SL_TYPE_COMPRESSED_TCP; | |
1200 | } else { | |
1201 | proto = PPP_VJC_UNCOMP; | |
1202 | cp[0] = skb->data[2]; | |
1203 | } | |
1204 | kfree_skb(skb); | |
1205 | skb = new_skb; | |
1206 | cp = skb_put(skb, len + 2); | |
1207 | cp[0] = 0; | |
1208 | cp[1] = proto; | |
1209 | } | |
1210 | break; | |
1211 | ||
1212 | case PPP_CCP: | |
1213 | /* peek at outbound CCP frames */ | |
1214 | ppp_ccp_peek(ppp, skb, 0); | |
1215 | break; | |
1216 | } | |
1217 | ||
1218 | /* try to do packet compression */ | |
cd228d54 | 1219 | if ((ppp->xstate & SC_COMP_RUN) && ppp->xc_state |
1da177e4 | 1220 | && proto != PPP_LCP && proto != PPP_CCP) { |
b3f9b92a MD |
1221 | if (!(ppp->flags & SC_CCP_UP) && (ppp->flags & SC_MUST_COMP)) { |
1222 | if (net_ratelimit()) | |
1223 | printk(KERN_ERR "ppp: compression required but down - pkt dropped.\n"); | |
1da177e4 LT |
1224 | goto drop; |
1225 | } | |
b3f9b92a MD |
1226 | skb = pad_compress_skb(ppp, skb); |
1227 | if (!skb) | |
1228 | goto drop; | |
1da177e4 LT |
1229 | } |
1230 | ||
1231 | /* | |
1232 | * If we are waiting for traffic (demand dialling), | |
1233 | * queue it up for pppd to receive. | |
1234 | */ | |
1235 | if (ppp->flags & SC_LOOP_TRAFFIC) { | |
1236 | if (ppp->file.rq.qlen > PPP_MAX_RQLEN) | |
1237 | goto drop; | |
1238 | skb_queue_tail(&ppp->file.rq, skb); | |
1239 | wake_up_interruptible(&ppp->file.rwait); | |
1240 | return; | |
1241 | } | |
1242 | ||
1243 | ppp->xmit_pending = skb; | |
1244 | ppp_push(ppp); | |
1245 | return; | |
1246 | ||
1247 | drop: | |
b3f9b92a MD |
1248 | if (skb) |
1249 | kfree_skb(skb); | |
8c0469cd | 1250 | ++ppp->dev->stats.tx_errors; |
1da177e4 LT |
1251 | } |
1252 | ||
1253 | /* | |
1254 | * Try to send the frame in xmit_pending. | |
1255 | * The caller should have the xmit path locked. | |
1256 | */ | |
1257 | static void | |
1258 | ppp_push(struct ppp *ppp) | |
1259 | { | |
1260 | struct list_head *list; | |
1261 | struct channel *pch; | |
1262 | struct sk_buff *skb = ppp->xmit_pending; | |
1263 | ||
cd228d54 | 1264 | if (!skb) |
1da177e4 LT |
1265 | return; |
1266 | ||
1267 | list = &ppp->channels; | |
1268 | if (list_empty(list)) { | |
1269 | /* nowhere to send the packet, just drop it */ | |
1270 | ppp->xmit_pending = NULL; | |
1271 | kfree_skb(skb); | |
1272 | return; | |
1273 | } | |
1274 | ||
1275 | if ((ppp->flags & SC_MULTILINK) == 0) { | |
1276 | /* not doing multilink: send it down the first channel */ | |
1277 | list = list->next; | |
1278 | pch = list_entry(list, struct channel, clist); | |
1279 | ||
1280 | spin_lock_bh(&pch->downl); | |
1281 | if (pch->chan) { | |
1282 | if (pch->chan->ops->start_xmit(pch->chan, skb)) | |
1283 | ppp->xmit_pending = NULL; | |
1284 | } else { | |
1285 | /* channel got unregistered */ | |
1286 | kfree_skb(skb); | |
1287 | ppp->xmit_pending = NULL; | |
1288 | } | |
1289 | spin_unlock_bh(&pch->downl); | |
1290 | return; | |
1291 | } | |
1292 | ||
1293 | #ifdef CONFIG_PPP_MULTILINK | |
1294 | /* Multilink: fragment the packet over as many links | |
1295 | as can take the packet at the moment. */ | |
1296 | if (!ppp_mp_explode(ppp, skb)) | |
1297 | return; | |
1298 | #endif /* CONFIG_PPP_MULTILINK */ | |
1299 | ||
1300 | ppp->xmit_pending = NULL; | |
1301 | kfree_skb(skb); | |
1302 | } | |
1303 | ||
1304 | #ifdef CONFIG_PPP_MULTILINK | |
1305 | /* | |
1306 | * Divide a packet to be transmitted into fragments and | |
1307 | * send them out the individual links. | |
1308 | */ | |
1309 | static int ppp_mp_explode(struct ppp *ppp, struct sk_buff *skb) | |
1310 | { | |
516cd15f | 1311 | int len, fragsize; |
1da177e4 | 1312 | int i, bits, hdrlen, mtu; |
516cd15f PM |
1313 | int flen; |
1314 | int navail, nfree; | |
1315 | int nbigger; | |
1da177e4 LT |
1316 | unsigned char *p, *q; |
1317 | struct list_head *list; | |
1318 | struct channel *pch; | |
1319 | struct sk_buff *frag; | |
1320 | struct ppp_channel *chan; | |
1321 | ||
516cd15f PM |
1322 | nfree = 0; /* # channels which have no packet already queued */ |
1323 | navail = 0; /* total # of usable channels (not deregistered) */ | |
1da177e4 | 1324 | hdrlen = (ppp->flags & SC_MP_XSHORTSEQ)? MPHDRLEN_SSN: MPHDRLEN; |
516cd15f | 1325 | i = 0; |
81616c5a | 1326 | list_for_each_entry(pch, &ppp->channels, clist) { |
516cd15f PM |
1327 | navail += pch->avail = (pch->chan != NULL); |
1328 | if (pch->avail) { | |
b03efcfb DM |
1329 | if (skb_queue_empty(&pch->file.xq) || |
1330 | !pch->had_frag) { | |
516cd15f PM |
1331 | pch->avail = 2; |
1332 | ++nfree; | |
1da177e4 | 1333 | } |
516cd15f PM |
1334 | if (!pch->had_frag && i < ppp->nxchan) |
1335 | ppp->nxchan = i; | |
1da177e4 | 1336 | } |
516cd15f | 1337 | ++i; |
1da177e4 | 1338 | } |
516cd15f PM |
1339 | |
1340 | /* | |
1341 | * Don't start sending this packet unless at least half of | |
1342 | * the channels are free. This gives much better TCP | |
1343 | * performance if we have a lot of channels. | |
1344 | */ | |
1345 | if (nfree == 0 || nfree < navail / 2) | |
1da177e4 LT |
1346 | return 0; /* can't take now, leave it in xmit_pending */ |
1347 | ||
1348 | /* Do protocol field compression (XXX this should be optional) */ | |
1349 | p = skb->data; | |
1350 | len = skb->len; | |
1351 | if (*p == 0) { | |
1352 | ++p; | |
1353 | --len; | |
1354 | } | |
1355 | ||
516cd15f PM |
1356 | /* |
1357 | * Decide on fragment size. | |
1358 | * We create a fragment for each free channel regardless of | |
1359 | * how small they are (i.e. even 0 length) in order to minimize | |
1360 | * the time that it will take to detect when a channel drops | |
1361 | * a fragment. | |
1362 | */ | |
1da177e4 | 1363 | fragsize = len; |
516cd15f | 1364 | if (nfree > 1) |
57cd5f75 | 1365 | fragsize = DIV_ROUND_UP(fragsize, nfree); |
516cd15f PM |
1366 | /* nbigger channels get fragsize bytes, the rest get fragsize-1, |
1367 | except if nbigger==0, then they all get fragsize. */ | |
1368 | nbigger = len % nfree; | |
1da177e4 LT |
1369 | |
1370 | /* skip to the channel after the one we last used | |
1371 | and start at that one */ | |
81616c5a | 1372 | list = &ppp->channels; |
1da177e4 LT |
1373 | for (i = 0; i < ppp->nxchan; ++i) { |
1374 | list = list->next; | |
1375 | if (list == &ppp->channels) { | |
1376 | i = 0; | |
1377 | break; | |
1378 | } | |
1379 | } | |
1380 | ||
1381 | /* create a fragment for each channel */ | |
1382 | bits = B; | |
516cd15f | 1383 | while (nfree > 0 || len > 0) { |
1da177e4 LT |
1384 | list = list->next; |
1385 | if (list == &ppp->channels) { | |
1386 | i = 0; | |
1387 | continue; | |
1388 | } | |
1389 | pch = list_entry(list, struct channel, clist); | |
1390 | ++i; | |
1391 | if (!pch->avail) | |
1392 | continue; | |
1393 | ||
516cd15f PM |
1394 | /* |
1395 | * Skip this channel if it has a fragment pending already and | |
1396 | * we haven't given a fragment to all of the free channels. | |
1397 | */ | |
1398 | if (pch->avail == 1) { | |
1399 | if (nfree > 0) | |
1400 | continue; | |
1401 | } else { | |
1402 | --nfree; | |
1403 | pch->avail = 1; | |
1404 | } | |
1405 | ||
1da177e4 LT |
1406 | /* check the channel's mtu and whether it is still attached. */ |
1407 | spin_lock_bh(&pch->downl); | |
516cd15f PM |
1408 | if (pch->chan == NULL) { |
1409 | /* can't use this channel, it's being deregistered */ | |
1da177e4 LT |
1410 | spin_unlock_bh(&pch->downl); |
1411 | pch->avail = 0; | |
516cd15f | 1412 | if (--navail == 0) |
1da177e4 LT |
1413 | break; |
1414 | continue; | |
1415 | } | |
1416 | ||
1417 | /* | |
516cd15f PM |
1418 | * Create a fragment for this channel of |
1419 | * min(max(mtu+2-hdrlen, 4), fragsize, len) bytes. | |
1420 | * If mtu+2-hdrlen < 4, that is a ridiculously small | |
1421 | * MTU, so we use mtu = 2 + hdrlen. | |
1da177e4 LT |
1422 | */ |
1423 | if (fragsize > len) | |
1424 | fragsize = len; | |
516cd15f PM |
1425 | flen = fragsize; |
1426 | mtu = pch->chan->mtu + 2 - hdrlen; | |
1427 | if (mtu < 4) | |
1428 | mtu = 4; | |
1429 | if (flen > mtu) | |
1430 | flen = mtu; | |
1431 | if (flen == len && nfree == 0) | |
1432 | bits |= E; | |
1433 | frag = alloc_skb(flen + hdrlen + (flen == 0), GFP_ATOMIC); | |
cd228d54 | 1434 | if (!frag) |
516cd15f PM |
1435 | goto noskb; |
1436 | q = skb_put(frag, flen + hdrlen); | |
1437 | ||
1438 | /* make the MP header */ | |
1439 | q[0] = PPP_MP >> 8; | |
1440 | q[1] = PPP_MP; | |
1441 | if (ppp->flags & SC_MP_XSHORTSEQ) { | |
1442 | q[2] = bits + ((ppp->nxseq >> 8) & 0xf); | |
1443 | q[3] = ppp->nxseq; | |
1444 | } else { | |
1445 | q[2] = bits; | |
1446 | q[3] = ppp->nxseq >> 16; | |
1447 | q[4] = ppp->nxseq >> 8; | |
1448 | q[5] = ppp->nxseq; | |
1da177e4 | 1449 | } |
516cd15f PM |
1450 | |
1451 | /* | |
1452 | * Copy the data in. | |
1453 | * Unfortunately there is a bug in older versions of | |
1454 | * the Linux PPP multilink reconstruction code where it | |
1455 | * drops 0-length fragments. Therefore we make sure the | |
1456 | * fragment has at least one byte of data. Any bytes | |
1457 | * we add in this situation will end up as padding on the | |
1458 | * end of the reconstructed packet. | |
1459 | */ | |
1460 | if (flen == 0) | |
1461 | *skb_put(frag, 1) = 0; | |
1462 | else | |
1463 | memcpy(q + hdrlen, p, flen); | |
1464 | ||
1465 | /* try to send it down the channel */ | |
1466 | chan = pch->chan; | |
b03efcfb DM |
1467 | if (!skb_queue_empty(&pch->file.xq) || |
1468 | !chan->ops->start_xmit(chan, frag)) | |
516cd15f PM |
1469 | skb_queue_tail(&pch->file.xq, frag); |
1470 | pch->had_frag = 1; | |
1471 | p += flen; | |
1472 | len -= flen; | |
1473 | ++ppp->nxseq; | |
1474 | bits = 0; | |
1da177e4 | 1475 | spin_unlock_bh(&pch->downl); |
516cd15f PM |
1476 | |
1477 | if (--nbigger == 0 && fragsize > 0) | |
1478 | --fragsize; | |
1479 | } | |
1da177e4 LT |
1480 | ppp->nxchan = i; |
1481 | ||
1482 | return 1; | |
1483 | ||
1484 | noskb: | |
1485 | spin_unlock_bh(&pch->downl); | |
1486 | if (ppp->debug & 1) | |
1487 | printk(KERN_ERR "PPP: no memory (fragment)\n"); | |
8c0469cd | 1488 | ++ppp->dev->stats.tx_errors; |
1da177e4 LT |
1489 | ++ppp->nxseq; |
1490 | return 1; /* abandon the frame */ | |
1491 | } | |
1492 | #endif /* CONFIG_PPP_MULTILINK */ | |
1493 | ||
1494 | /* | |
1495 | * Try to send data out on a channel. | |
1496 | */ | |
1497 | static void | |
1498 | ppp_channel_push(struct channel *pch) | |
1499 | { | |
1500 | struct sk_buff *skb; | |
1501 | struct ppp *ppp; | |
1502 | ||
1503 | spin_lock_bh(&pch->downl); | |
cd228d54 | 1504 | if (pch->chan) { |
b03efcfb | 1505 | while (!skb_queue_empty(&pch->file.xq)) { |
1da177e4 LT |
1506 | skb = skb_dequeue(&pch->file.xq); |
1507 | if (!pch->chan->ops->start_xmit(pch->chan, skb)) { | |
1508 | /* put the packet back and try again later */ | |
1509 | skb_queue_head(&pch->file.xq, skb); | |
1510 | break; | |
1511 | } | |
1512 | } | |
1513 | } else { | |
1514 | /* channel got deregistered */ | |
1515 | skb_queue_purge(&pch->file.xq); | |
1516 | } | |
1517 | spin_unlock_bh(&pch->downl); | |
1518 | /* see if there is anything from the attached unit to be sent */ | |
b03efcfb | 1519 | if (skb_queue_empty(&pch->file.xq)) { |
1da177e4 LT |
1520 | read_lock_bh(&pch->upl); |
1521 | ppp = pch->ppp; | |
cd228d54 | 1522 | if (ppp) |
1da177e4 LT |
1523 | ppp_xmit_process(ppp); |
1524 | read_unlock_bh(&pch->upl); | |
1525 | } | |
1526 | } | |
1527 | ||
1528 | /* | |
1529 | * Receive-side routines. | |
1530 | */ | |
1531 | ||
1532 | /* misuse a few fields of the skb for MP reconstruction */ | |
1533 | #define sequence priority | |
1534 | #define BEbits cb[0] | |
1535 | ||
1536 | static inline void | |
1537 | ppp_do_recv(struct ppp *ppp, struct sk_buff *skb, struct channel *pch) | |
1538 | { | |
1539 | ppp_recv_lock(ppp); | |
739840d5 | 1540 | if (!ppp->closing) |
1da177e4 LT |
1541 | ppp_receive_frame(ppp, skb, pch); |
1542 | else | |
1543 | kfree_skb(skb); | |
1544 | ppp_recv_unlock(ppp); | |
1545 | } | |
1546 | ||
1547 | void | |
1548 | ppp_input(struct ppp_channel *chan, struct sk_buff *skb) | |
1549 | { | |
1550 | struct channel *pch = chan->ppp; | |
1551 | int proto; | |
1552 | ||
cd228d54 | 1553 | if (!pch || skb->len == 0) { |
1da177e4 LT |
1554 | kfree_skb(skb); |
1555 | return; | |
1556 | } | |
516cd15f | 1557 | |
1da177e4 LT |
1558 | proto = PPP_PROTO(skb); |
1559 | read_lock_bh(&pch->upl); | |
cd228d54 | 1560 | if (!pch->ppp || proto >= 0xc000 || proto == PPP_CCPFRAG) { |
1da177e4 LT |
1561 | /* put it on the channel queue */ |
1562 | skb_queue_tail(&pch->file.rq, skb); | |
1563 | /* drop old frames if queue too long */ | |
1564 | while (pch->file.rq.qlen > PPP_MAX_RQLEN | |
cd228d54 | 1565 | && (skb = skb_dequeue(&pch->file.rq))) |
1da177e4 LT |
1566 | kfree_skb(skb); |
1567 | wake_up_interruptible(&pch->file.rwait); | |
1568 | } else { | |
1569 | ppp_do_recv(pch->ppp, skb, pch); | |
1570 | } | |
1571 | read_unlock_bh(&pch->upl); | |
1572 | } | |
1573 | ||
1574 | /* Put a 0-length skb in the receive queue as an error indication */ | |
1575 | void | |
1576 | ppp_input_error(struct ppp_channel *chan, int code) | |
1577 | { | |
1578 | struct channel *pch = chan->ppp; | |
1579 | struct sk_buff *skb; | |
1580 | ||
cd228d54 | 1581 | if (!pch) |
1da177e4 LT |
1582 | return; |
1583 | ||
1584 | read_lock_bh(&pch->upl); | |
cd228d54 | 1585 | if (pch->ppp) { |
1da177e4 | 1586 | skb = alloc_skb(0, GFP_ATOMIC); |
cd228d54 | 1587 | if (skb) { |
1da177e4 LT |
1588 | skb->len = 0; /* probably unnecessary */ |
1589 | skb->cb[0] = code; | |
1590 | ppp_do_recv(pch->ppp, skb, pch); | |
1591 | } | |
1592 | } | |
1593 | read_unlock_bh(&pch->upl); | |
1594 | } | |
1595 | ||
1596 | /* | |
1597 | * We come in here to process a received frame. | |
1598 | * The receive side of the ppp unit is locked. | |
1599 | */ | |
1600 | static void | |
1601 | ppp_receive_frame(struct ppp *ppp, struct sk_buff *skb, struct channel *pch) | |
1602 | { | |
2a38b775 | 1603 | if (pskb_may_pull(skb, 2)) { |
1da177e4 LT |
1604 | #ifdef CONFIG_PPP_MULTILINK |
1605 | /* XXX do channel-level decompression here */ | |
1606 | if (PPP_PROTO(skb) == PPP_MP) | |
1607 | ppp_receive_mp_frame(ppp, skb, pch); | |
1608 | else | |
1609 | #endif /* CONFIG_PPP_MULTILINK */ | |
1610 | ppp_receive_nonmp_frame(ppp, skb); | |
1611 | return; | |
1612 | } | |
1613 | ||
1614 | if (skb->len > 0) | |
1615 | /* note: a 0-length skb is used as an error indication */ | |
8c0469cd | 1616 | ++ppp->dev->stats.rx_length_errors; |
1da177e4 LT |
1617 | |
1618 | kfree_skb(skb); | |
1619 | ppp_receive_error(ppp); | |
1620 | } | |
1621 | ||
1622 | static void | |
1623 | ppp_receive_error(struct ppp *ppp) | |
1624 | { | |
8c0469cd | 1625 | ++ppp->dev->stats.rx_errors; |
cd228d54 | 1626 | if (ppp->vj) |
1da177e4 LT |
1627 | slhc_toss(ppp->vj); |
1628 | } | |
1629 | ||
1630 | static void | |
1631 | ppp_receive_nonmp_frame(struct ppp *ppp, struct sk_buff *skb) | |
1632 | { | |
1633 | struct sk_buff *ns; | |
1634 | int proto, len, npi; | |
1635 | ||
1636 | /* | |
1637 | * Decompress the frame, if compressed. | |
1638 | * Note that some decompressors need to see uncompressed frames | |
1639 | * that come in as well as compressed frames. | |
1640 | */ | |
cd228d54 | 1641 | if (ppp->rc_state && (ppp->rstate & SC_DECOMP_RUN) |
1da177e4 LT |
1642 | && (ppp->rstate & (SC_DC_FERROR | SC_DC_ERROR)) == 0) |
1643 | skb = ppp_decompress_frame(ppp, skb); | |
1644 | ||
b3f9b92a MD |
1645 | if (ppp->flags & SC_MUST_COMP && ppp->rstate & SC_DC_FERROR) |
1646 | goto err; | |
1647 | ||
1da177e4 LT |
1648 | proto = PPP_PROTO(skb); |
1649 | switch (proto) { | |
1650 | case PPP_VJC_COMP: | |
1651 | /* decompress VJ compressed packets */ | |
cd228d54 | 1652 | if (!ppp->vj || (ppp->flags & SC_REJ_COMP_TCP)) |
1da177e4 LT |
1653 | goto err; |
1654 | ||
2a38b775 | 1655 | if (skb_tailroom(skb) < 124 || skb_cloned(skb)) { |
1da177e4 LT |
1656 | /* copy to a new sk_buff with more tailroom */ |
1657 | ns = dev_alloc_skb(skb->len + 128); | |
cd228d54 | 1658 | if (!ns) { |
1da177e4 LT |
1659 | printk(KERN_ERR"PPP: no memory (VJ decomp)\n"); |
1660 | goto err; | |
1661 | } | |
1662 | skb_reserve(ns, 2); | |
1663 | skb_copy_bits(skb, 0, skb_put(ns, skb->len), skb->len); | |
1664 | kfree_skb(skb); | |
1665 | skb = ns; | |
1666 | } | |
e3f749c4 HX |
1667 | else |
1668 | skb->ip_summed = CHECKSUM_NONE; | |
1da177e4 LT |
1669 | |
1670 | len = slhc_uncompress(ppp->vj, skb->data + 2, skb->len - 2); | |
1671 | if (len <= 0) { | |
1672 | printk(KERN_DEBUG "PPP: VJ decompression error\n"); | |
1673 | goto err; | |
1674 | } | |
1675 | len += 2; | |
1676 | if (len > skb->len) | |
1677 | skb_put(skb, len - skb->len); | |
1678 | else if (len < skb->len) | |
1679 | skb_trim(skb, len); | |
1680 | proto = PPP_IP; | |
1681 | break; | |
1682 | ||
1683 | case PPP_VJC_UNCOMP: | |
cd228d54 | 1684 | if (!ppp->vj || (ppp->flags & SC_REJ_COMP_TCP)) |
1da177e4 | 1685 | goto err; |
6aa20a22 | 1686 | |
1da177e4 LT |
1687 | /* Until we fix the decompressor need to make sure |
1688 | * data portion is linear. | |
1689 | */ | |
6aa20a22 | 1690 | if (!pskb_may_pull(skb, skb->len)) |
1da177e4 LT |
1691 | goto err; |
1692 | ||
1693 | if (slhc_remember(ppp->vj, skb->data + 2, skb->len - 2) <= 0) { | |
1694 | printk(KERN_ERR "PPP: VJ uncompressed error\n"); | |
1695 | goto err; | |
1696 | } | |
1697 | proto = PPP_IP; | |
1698 | break; | |
1699 | ||
1700 | case PPP_CCP: | |
1701 | ppp_ccp_peek(ppp, skb, 1); | |
1702 | break; | |
1703 | } | |
1704 | ||
8c0469cd PZ |
1705 | ++ppp->dev->stats.rx_packets; |
1706 | ppp->dev->stats.rx_bytes += skb->len - 2; | |
1da177e4 LT |
1707 | |
1708 | npi = proto_to_npindex(proto); | |
1709 | if (npi < 0) { | |
1710 | /* control or unknown frame - pass it to pppd */ | |
1711 | skb_queue_tail(&ppp->file.rq, skb); | |
1712 | /* limit queue length by dropping old frames */ | |
1713 | while (ppp->file.rq.qlen > PPP_MAX_RQLEN | |
cd228d54 | 1714 | && (skb = skb_dequeue(&ppp->file.rq))) |
1da177e4 LT |
1715 | kfree_skb(skb); |
1716 | /* wake up any process polling or blocking on read */ | |
1717 | wake_up_interruptible(&ppp->file.rwait); | |
1718 | ||
1719 | } else { | |
1720 | /* network protocol frame - give it to the kernel */ | |
1721 | ||
1722 | #ifdef CONFIG_PPP_FILTER | |
1723 | /* check if the packet passes the pass and active filters */ | |
1724 | /* the filter instructions are constructed assuming | |
1725 | a four-byte PPP header on each packet */ | |
2a38b775 HX |
1726 | if (ppp->pass_filter || ppp->active_filter) { |
1727 | if (skb_cloned(skb) && | |
1728 | pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) | |
1729 | goto err; | |
1730 | ||
1731 | *skb_push(skb, 2) = 0; | |
1732 | if (ppp->pass_filter | |
1733 | && sk_run_filter(skb, ppp->pass_filter, | |
1734 | ppp->pass_len) == 0) { | |
1735 | if (ppp->debug & 1) | |
1736 | printk(KERN_DEBUG "PPP: inbound frame " | |
1737 | "not passed\n"); | |
1738 | kfree_skb(skb); | |
1739 | return; | |
1740 | } | |
1741 | if (!(ppp->active_filter | |
1742 | && sk_run_filter(skb, ppp->active_filter, | |
1743 | ppp->active_len) == 0)) | |
1744 | ppp->last_recv = jiffies; | |
1745 | __skb_pull(skb, 2); | |
1746 | } else | |
1da177e4 | 1747 | #endif /* CONFIG_PPP_FILTER */ |
2a38b775 | 1748 | ppp->last_recv = jiffies; |
1da177e4 LT |
1749 | |
1750 | if ((ppp->dev->flags & IFF_UP) == 0 | |
1751 | || ppp->npmode[npi] != NPMODE_PASS) { | |
1752 | kfree_skb(skb); | |
1753 | } else { | |
cbb042f9 HX |
1754 | /* chop off protocol */ |
1755 | skb_pull_rcsum(skb, 2); | |
1da177e4 LT |
1756 | skb->dev = ppp->dev; |
1757 | skb->protocol = htons(npindex_to_ethertype[npi]); | |
459a98ed | 1758 | skb_reset_mac_header(skb); |
1da177e4 | 1759 | netif_rx(skb); |
1da177e4 LT |
1760 | } |
1761 | } | |
1762 | return; | |
1763 | ||
1764 | err: | |
1765 | kfree_skb(skb); | |
1766 | ppp_receive_error(ppp); | |
1767 | } | |
1768 | ||
1769 | static struct sk_buff * | |
1770 | ppp_decompress_frame(struct ppp *ppp, struct sk_buff *skb) | |
1771 | { | |
1772 | int proto = PPP_PROTO(skb); | |
1773 | struct sk_buff *ns; | |
1774 | int len; | |
1775 | ||
1776 | /* Until we fix all the decompressor's need to make sure | |
1777 | * data portion is linear. | |
1778 | */ | |
1779 | if (!pskb_may_pull(skb, skb->len)) | |
1780 | goto err; | |
1781 | ||
1782 | if (proto == PPP_COMP) { | |
4b2a8fb3 KS |
1783 | int obuff_size; |
1784 | ||
1785 | switch(ppp->rcomp->compress_proto) { | |
1786 | case CI_MPPE: | |
1787 | obuff_size = ppp->mru + PPP_HDRLEN + 1; | |
1788 | break; | |
1789 | default: | |
1790 | obuff_size = ppp->mru + PPP_HDRLEN; | |
1791 | break; | |
1792 | } | |
1793 | ||
1794 | ns = dev_alloc_skb(obuff_size); | |
cd228d54 | 1795 | if (!ns) { |
1da177e4 LT |
1796 | printk(KERN_ERR "ppp_decompress_frame: no memory\n"); |
1797 | goto err; | |
1798 | } | |
1799 | /* the decompressor still expects the A/C bytes in the hdr */ | |
1800 | len = ppp->rcomp->decompress(ppp->rc_state, skb->data - 2, | |
06c7af56 | 1801 | skb->len + 2, ns->data, obuff_size); |
1da177e4 LT |
1802 | if (len < 0) { |
1803 | /* Pass the compressed frame to pppd as an | |
1804 | error indication. */ | |
1805 | if (len == DECOMP_FATALERROR) | |
1806 | ppp->rstate |= SC_DC_FERROR; | |
1807 | kfree_skb(ns); | |
1808 | goto err; | |
1809 | } | |
1810 | ||
1811 | kfree_skb(skb); | |
1812 | skb = ns; | |
1813 | skb_put(skb, len); | |
1814 | skb_pull(skb, 2); /* pull off the A/C bytes */ | |
1815 | ||
1816 | } else { | |
1817 | /* Uncompressed frame - pass to decompressor so it | |
1818 | can update its dictionary if necessary. */ | |
1819 | if (ppp->rcomp->incomp) | |
1820 | ppp->rcomp->incomp(ppp->rc_state, skb->data - 2, | |
1821 | skb->len + 2); | |
1822 | } | |
1823 | ||
1824 | return skb; | |
1825 | ||
1826 | err: | |
1827 | ppp->rstate |= SC_DC_ERROR; | |
1828 | ppp_receive_error(ppp); | |
1829 | return skb; | |
1830 | } | |
1831 | ||
1832 | #ifdef CONFIG_PPP_MULTILINK | |
1833 | /* | |
1834 | * Receive a multilink frame. | |
1835 | * We put it on the reconstruction queue and then pull off | |
1836 | * as many completed frames as we can. | |
1837 | */ | |
1838 | static void | |
1839 | ppp_receive_mp_frame(struct ppp *ppp, struct sk_buff *skb, struct channel *pch) | |
1840 | { | |
1841 | u32 mask, seq; | |
81616c5a | 1842 | struct channel *ch; |
1da177e4 LT |
1843 | int mphdrlen = (ppp->flags & SC_MP_SHORTSEQ)? MPHDRLEN_SSN: MPHDRLEN; |
1844 | ||
2a38b775 | 1845 | if (!pskb_may_pull(skb, mphdrlen + 1) || ppp->mrru == 0) |
1da177e4 LT |
1846 | goto err; /* no good, throw it away */ |
1847 | ||
1848 | /* Decode sequence number and begin/end bits */ | |
1849 | if (ppp->flags & SC_MP_SHORTSEQ) { | |
1850 | seq = ((skb->data[2] & 0x0f) << 8) | skb->data[3]; | |
1851 | mask = 0xfff; | |
1852 | } else { | |
1853 | seq = (skb->data[3] << 16) | (skb->data[4] << 8)| skb->data[5]; | |
1854 | mask = 0xffffff; | |
1855 | } | |
1856 | skb->BEbits = skb->data[2]; | |
1857 | skb_pull(skb, mphdrlen); /* pull off PPP and MP headers */ | |
1858 | ||
1859 | /* | |
1860 | * Do protocol ID decompression on the first fragment of each packet. | |
1861 | */ | |
1862 | if ((skb->BEbits & B) && (skb->data[0] & 1)) | |
1863 | *skb_push(skb, 1) = 0; | |
1864 | ||
1865 | /* | |
1866 | * Expand sequence number to 32 bits, making it as close | |
1867 | * as possible to ppp->minseq. | |
1868 | */ | |
1869 | seq |= ppp->minseq & ~mask; | |
1870 | if ((int)(ppp->minseq - seq) > (int)(mask >> 1)) | |
1871 | seq += mask + 1; | |
1872 | else if ((int)(seq - ppp->minseq) > (int)(mask >> 1)) | |
1873 | seq -= mask + 1; /* should never happen */ | |
1874 | skb->sequence = seq; | |
1875 | pch->lastseq = seq; | |
1876 | ||
1877 | /* | |
1878 | * If this packet comes before the next one we were expecting, | |
1879 | * drop it. | |
1880 | */ | |
1881 | if (seq_before(seq, ppp->nextseq)) { | |
1882 | kfree_skb(skb); | |
8c0469cd | 1883 | ++ppp->dev->stats.rx_dropped; |
1da177e4 LT |
1884 | ppp_receive_error(ppp); |
1885 | return; | |
1886 | } | |
1887 | ||
1888 | /* | |
1889 | * Reevaluate minseq, the minimum over all channels of the | |
1890 | * last sequence number received on each channel. Because of | |
1891 | * the increasing sequence number rule, we know that any fragment | |
1892 | * before `minseq' which hasn't arrived is never going to arrive. | |
1893 | * The list of channels can't change because we have the receive | |
1894 | * side of the ppp unit locked. | |
1895 | */ | |
81616c5a | 1896 | list_for_each_entry(ch, &ppp->channels, clist) { |
1da177e4 LT |
1897 | if (seq_before(ch->lastseq, seq)) |
1898 | seq = ch->lastseq; | |
1899 | } | |
1900 | if (seq_before(ppp->minseq, seq)) | |
1901 | ppp->minseq = seq; | |
1902 | ||
1903 | /* Put the fragment on the reconstruction queue */ | |
1904 | ppp_mp_insert(ppp, skb); | |
1905 | ||
1906 | /* If the queue is getting long, don't wait any longer for packets | |
1907 | before the start of the queue. */ | |
38ce7c73 DM |
1908 | if (skb_queue_len(&ppp->mrq) >= PPP_MP_MAX_QLEN) { |
1909 | struct sk_buff *skb = skb_peek(&ppp->mrq); | |
1910 | if (seq_before(ppp->minseq, skb->sequence)) | |
1911 | ppp->minseq = skb->sequence; | |
1912 | } | |
1da177e4 LT |
1913 | |
1914 | /* Pull completed packets off the queue and receive them. */ | |
cd228d54 | 1915 | while ((skb = ppp_mp_reconstruct(ppp))) |
1da177e4 LT |
1916 | ppp_receive_nonmp_frame(ppp, skb); |
1917 | ||
1918 | return; | |
1919 | ||
1920 | err: | |
1921 | kfree_skb(skb); | |
1922 | ppp_receive_error(ppp); | |
1923 | } | |
1924 | ||
1925 | /* | |
1926 | * Insert a fragment on the MP reconstruction queue. | |
1927 | * The queue is ordered by increasing sequence number. | |
1928 | */ | |
1929 | static void | |
1930 | ppp_mp_insert(struct ppp *ppp, struct sk_buff *skb) | |
1931 | { | |
1932 | struct sk_buff *p; | |
1933 | struct sk_buff_head *list = &ppp->mrq; | |
1934 | u32 seq = skb->sequence; | |
1935 | ||
1936 | /* N.B. we don't need to lock the list lock because we have the | |
1937 | ppp unit receive-side lock. */ | |
13c9821e | 1938 | skb_queue_walk(list, p) { |
1da177e4 LT |
1939 | if (seq_before(seq, p->sequence)) |
1940 | break; | |
13c9821e | 1941 | } |
43f59c89 | 1942 | __skb_queue_before(list, p, skb); |
1da177e4 LT |
1943 | } |
1944 | ||
1945 | /* | |
1946 | * Reconstruct a packet from the MP fragment queue. | |
1947 | * We go through increasing sequence numbers until we find a | |
1948 | * complete packet, or we get to the sequence number for a fragment | |
1949 | * which hasn't arrived but might still do so. | |
1950 | */ | |
3c582b30 | 1951 | static struct sk_buff * |
1da177e4 LT |
1952 | ppp_mp_reconstruct(struct ppp *ppp) |
1953 | { | |
1954 | u32 seq = ppp->nextseq; | |
1955 | u32 minseq = ppp->minseq; | |
1956 | struct sk_buff_head *list = &ppp->mrq; | |
1957 | struct sk_buff *p, *next; | |
1958 | struct sk_buff *head, *tail; | |
1959 | struct sk_buff *skb = NULL; | |
1960 | int lost = 0, len = 0; | |
1961 | ||
1962 | if (ppp->mrru == 0) /* do nothing until mrru is set */ | |
1963 | return NULL; | |
1964 | head = list->next; | |
1965 | tail = NULL; | |
1966 | for (p = head; p != (struct sk_buff *) list; p = next) { | |
1967 | next = p->next; | |
1968 | if (seq_before(p->sequence, seq)) { | |
1969 | /* this can't happen, anyway ignore the skb */ | |
1970 | printk(KERN_ERR "ppp_mp_reconstruct bad seq %u < %u\n", | |
1971 | p->sequence, seq); | |
1972 | head = next; | |
1973 | continue; | |
1974 | } | |
1975 | if (p->sequence != seq) { | |
1976 | /* Fragment `seq' is missing. If it is after | |
1977 | minseq, it might arrive later, so stop here. */ | |
1978 | if (seq_after(seq, minseq)) | |
1979 | break; | |
1980 | /* Fragment `seq' is lost, keep going. */ | |
1981 | lost = 1; | |
1982 | seq = seq_before(minseq, p->sequence)? | |
1983 | minseq + 1: p->sequence; | |
1984 | next = p; | |
1985 | continue; | |
1986 | } | |
1987 | ||
1988 | /* | |
1989 | * At this point we know that all the fragments from | |
1990 | * ppp->nextseq to seq are either present or lost. | |
1991 | * Also, there are no complete packets in the queue | |
1992 | * that have no missing fragments and end before this | |
1993 | * fragment. | |
1994 | */ | |
1995 | ||
1996 | /* B bit set indicates this fragment starts a packet */ | |
1997 | if (p->BEbits & B) { | |
1998 | head = p; | |
1999 | lost = 0; | |
2000 | len = 0; | |
2001 | } | |
2002 | ||
2003 | len += p->len; | |
2004 | ||
2005 | /* Got a complete packet yet? */ | |
2006 | if (lost == 0 && (p->BEbits & E) && (head->BEbits & B)) { | |
2007 | if (len > ppp->mrru + 2) { | |
8c0469cd | 2008 | ++ppp->dev->stats.rx_length_errors; |
1da177e4 LT |
2009 | printk(KERN_DEBUG "PPP: reconstructed packet" |
2010 | " is too long (%d)\n", len); | |
2011 | } else if (p == head) { | |
2012 | /* fragment is complete packet - reuse skb */ | |
2013 | tail = p; | |
2014 | skb = skb_get(p); | |
2015 | break; | |
2016 | } else if ((skb = dev_alloc_skb(len)) == NULL) { | |
8c0469cd | 2017 | ++ppp->dev->stats.rx_missed_errors; |
1da177e4 LT |
2018 | printk(KERN_DEBUG "PPP: no memory for " |
2019 | "reconstructed packet"); | |
2020 | } else { | |
2021 | tail = p; | |
2022 | break; | |
2023 | } | |
2024 | ppp->nextseq = seq + 1; | |
2025 | } | |
2026 | ||
2027 | /* | |
2028 | * If this is the ending fragment of a packet, | |
2029 | * and we haven't found a complete valid packet yet, | |
2030 | * we can discard up to and including this fragment. | |
2031 | */ | |
2032 | if (p->BEbits & E) | |
2033 | head = next; | |
2034 | ||
2035 | ++seq; | |
2036 | } | |
2037 | ||
2038 | /* If we have a complete packet, copy it all into one skb. */ | |
2039 | if (tail != NULL) { | |
2040 | /* If we have discarded any fragments, | |
2041 | signal a receive error. */ | |
2042 | if (head->sequence != ppp->nextseq) { | |
2043 | if (ppp->debug & 1) | |
2044 | printk(KERN_DEBUG " missed pkts %u..%u\n", | |
2045 | ppp->nextseq, head->sequence-1); | |
8c0469cd | 2046 | ++ppp->dev->stats.rx_dropped; |
1da177e4 LT |
2047 | ppp_receive_error(ppp); |
2048 | } | |
2049 | ||
2050 | if (head != tail) | |
2051 | /* copy to a single skb */ | |
2052 | for (p = head; p != tail->next; p = p->next) | |
2053 | skb_copy_bits(p, 0, skb_put(skb, p->len), p->len); | |
2054 | ppp->nextseq = tail->sequence + 1; | |
2055 | head = tail->next; | |
2056 | } | |
2057 | ||
2058 | /* Discard all the skbuffs that we have copied the data out of | |
2059 | or that we can't use. */ | |
2060 | while ((p = list->next) != head) { | |
2061 | __skb_unlink(p, list); | |
2062 | kfree_skb(p); | |
2063 | } | |
2064 | ||
2065 | return skb; | |
2066 | } | |
2067 | #endif /* CONFIG_PPP_MULTILINK */ | |
2068 | ||
2069 | /* | |
2070 | * Channel interface. | |
2071 | */ | |
2072 | ||
273ec51d CG |
2073 | /* Create a new, unattached ppp channel. */ |
2074 | int ppp_register_channel(struct ppp_channel *chan) | |
2075 | { | |
2076 | return ppp_register_net_channel(current->nsproxy->net_ns, chan); | |
2077 | } | |
2078 | ||
2079 | /* Create a new, unattached ppp channel for specified net. */ | |
2080 | int ppp_register_net_channel(struct net *net, struct ppp_channel *chan) | |
1da177e4 LT |
2081 | { |
2082 | struct channel *pch; | |
273ec51d | 2083 | struct ppp_net *pn; |
1da177e4 | 2084 | |
d4274b51 | 2085 | pch = kzalloc(sizeof(struct channel), GFP_KERNEL); |
cd228d54 | 2086 | if (!pch) |
1da177e4 | 2087 | return -ENOMEM; |
273ec51d CG |
2088 | |
2089 | pn = ppp_pernet(net); | |
2090 | ||
1da177e4 LT |
2091 | pch->ppp = NULL; |
2092 | pch->chan = chan; | |
273ec51d | 2093 | pch->chan_net = net; |
1da177e4 LT |
2094 | chan->ppp = pch; |
2095 | init_ppp_file(&pch->file, CHANNEL); | |
2096 | pch->file.hdrlen = chan->hdrlen; | |
2097 | #ifdef CONFIG_PPP_MULTILINK | |
2098 | pch->lastseq = -1; | |
2099 | #endif /* CONFIG_PPP_MULTILINK */ | |
2100 | init_rwsem(&pch->chan_sem); | |
2101 | spin_lock_init(&pch->downl); | |
2102 | rwlock_init(&pch->upl); | |
273ec51d CG |
2103 | |
2104 | spin_lock_bh(&pn->all_channels_lock); | |
2105 | pch->file.index = ++pn->last_channel_index; | |
2106 | list_add(&pch->list, &pn->new_channels); | |
1da177e4 | 2107 | atomic_inc(&channel_count); |
273ec51d CG |
2108 | spin_unlock_bh(&pn->all_channels_lock); |
2109 | ||
1da177e4 LT |
2110 | return 0; |
2111 | } | |
2112 | ||
2113 | /* | |
2114 | * Return the index of a channel. | |
2115 | */ | |
2116 | int ppp_channel_index(struct ppp_channel *chan) | |
2117 | { | |
2118 | struct channel *pch = chan->ppp; | |
2119 | ||
cd228d54 | 2120 | if (pch) |
1da177e4 LT |
2121 | return pch->file.index; |
2122 | return -1; | |
2123 | } | |
2124 | ||
2125 | /* | |
2126 | * Return the PPP unit number to which a channel is connected. | |
2127 | */ | |
2128 | int ppp_unit_number(struct ppp_channel *chan) | |
2129 | { | |
2130 | struct channel *pch = chan->ppp; | |
2131 | int unit = -1; | |
2132 | ||
cd228d54 | 2133 | if (pch) { |
1da177e4 | 2134 | read_lock_bh(&pch->upl); |
cd228d54 | 2135 | if (pch->ppp) |
1da177e4 LT |
2136 | unit = pch->ppp->file.index; |
2137 | read_unlock_bh(&pch->upl); | |
2138 | } | |
2139 | return unit; | |
2140 | } | |
2141 | ||
2142 | /* | |
2143 | * Disconnect a channel from the generic layer. | |
2144 | * This must be called in process context. | |
2145 | */ | |
2146 | void | |
2147 | ppp_unregister_channel(struct ppp_channel *chan) | |
2148 | { | |
2149 | struct channel *pch = chan->ppp; | |
273ec51d | 2150 | struct ppp_net *pn; |
1da177e4 | 2151 | |
cd228d54 | 2152 | if (!pch) |
1da177e4 | 2153 | return; /* should never happen */ |
273ec51d | 2154 | |
1da177e4 LT |
2155 | chan->ppp = NULL; |
2156 | ||
2157 | /* | |
2158 | * This ensures that we have returned from any calls into the | |
2159 | * the channel's start_xmit or ioctl routine before we proceed. | |
2160 | */ | |
2161 | down_write(&pch->chan_sem); | |
2162 | spin_lock_bh(&pch->downl); | |
2163 | pch->chan = NULL; | |
2164 | spin_unlock_bh(&pch->downl); | |
2165 | up_write(&pch->chan_sem); | |
2166 | ppp_disconnect_channel(pch); | |
273ec51d CG |
2167 | |
2168 | pn = ppp_pernet(pch->chan_net); | |
2169 | spin_lock_bh(&pn->all_channels_lock); | |
1da177e4 | 2170 | list_del(&pch->list); |
273ec51d CG |
2171 | spin_unlock_bh(&pn->all_channels_lock); |
2172 | ||
1da177e4 LT |
2173 | pch->file.dead = 1; |
2174 | wake_up_interruptible(&pch->file.rwait); | |
2175 | if (atomic_dec_and_test(&pch->file.refcnt)) | |
2176 | ppp_destroy_channel(pch); | |
2177 | } | |
2178 | ||
2179 | /* | |
2180 | * Callback from a channel when it can accept more to transmit. | |
2181 | * This should be called at BH/softirq level, not interrupt level. | |
2182 | */ | |
2183 | void | |
2184 | ppp_output_wakeup(struct ppp_channel *chan) | |
2185 | { | |
2186 | struct channel *pch = chan->ppp; | |
2187 | ||
cd228d54 | 2188 | if (!pch) |
1da177e4 LT |
2189 | return; |
2190 | ppp_channel_push(pch); | |
2191 | } | |
2192 | ||
2193 | /* | |
2194 | * Compression control. | |
2195 | */ | |
2196 | ||
2197 | /* Process the PPPIOCSCOMPRESS ioctl. */ | |
2198 | static int | |
2199 | ppp_set_compress(struct ppp *ppp, unsigned long arg) | |
2200 | { | |
2201 | int err; | |
2202 | struct compressor *cp, *ocomp; | |
2203 | struct ppp_option_data data; | |
2204 | void *state, *ostate; | |
2205 | unsigned char ccp_option[CCP_MAX_OPTION_LENGTH]; | |
2206 | ||
2207 | err = -EFAULT; | |
2208 | if (copy_from_user(&data, (void __user *) arg, sizeof(data)) | |
2209 | || (data.length <= CCP_MAX_OPTION_LENGTH | |
2210 | && copy_from_user(ccp_option, (void __user *) data.ptr, data.length))) | |
2211 | goto out; | |
2212 | err = -EINVAL; | |
2213 | if (data.length > CCP_MAX_OPTION_LENGTH | |
2214 | || ccp_option[1] < 2 || ccp_option[1] > data.length) | |
2215 | goto out; | |
2216 | ||
a65e5d78 JB |
2217 | cp = try_then_request_module( |
2218 | find_compressor(ccp_option[0]), | |
2219 | "ppp-compress-%d", ccp_option[0]); | |
cd228d54 | 2220 | if (!cp) |
1da177e4 LT |
2221 | goto out; |
2222 | ||
2223 | err = -ENOBUFS; | |
2224 | if (data.transmit) { | |
2225 | state = cp->comp_alloc(ccp_option, data.length); | |
cd228d54 | 2226 | if (state) { |
1da177e4 LT |
2227 | ppp_xmit_lock(ppp); |
2228 | ppp->xstate &= ~SC_COMP_RUN; | |
2229 | ocomp = ppp->xcomp; | |
2230 | ostate = ppp->xc_state; | |
2231 | ppp->xcomp = cp; | |
2232 | ppp->xc_state = state; | |
2233 | ppp_xmit_unlock(ppp); | |
cd228d54 | 2234 | if (ostate) { |
1da177e4 LT |
2235 | ocomp->comp_free(ostate); |
2236 | module_put(ocomp->owner); | |
2237 | } | |
2238 | err = 0; | |
2239 | } else | |
2240 | module_put(cp->owner); | |
2241 | ||
2242 | } else { | |
2243 | state = cp->decomp_alloc(ccp_option, data.length); | |
cd228d54 | 2244 | if (state) { |
1da177e4 LT |
2245 | ppp_recv_lock(ppp); |
2246 | ppp->rstate &= ~SC_DECOMP_RUN; | |
2247 | ocomp = ppp->rcomp; | |
2248 | ostate = ppp->rc_state; | |
2249 | ppp->rcomp = cp; | |
2250 | ppp->rc_state = state; | |
2251 | ppp_recv_unlock(ppp); | |
cd228d54 | 2252 | if (ostate) { |
1da177e4 LT |
2253 | ocomp->decomp_free(ostate); |
2254 | module_put(ocomp->owner); | |
2255 | } | |
2256 | err = 0; | |
2257 | } else | |
2258 | module_put(cp->owner); | |
2259 | } | |
2260 | ||
2261 | out: | |
2262 | return err; | |
2263 | } | |
2264 | ||
2265 | /* | |
2266 | * Look at a CCP packet and update our state accordingly. | |
2267 | * We assume the caller has the xmit or recv path locked. | |
2268 | */ | |
2269 | static void | |
2270 | ppp_ccp_peek(struct ppp *ppp, struct sk_buff *skb, int inbound) | |
2271 | { | |
2272 | unsigned char *dp; | |
2273 | int len; | |
2274 | ||
2275 | if (!pskb_may_pull(skb, CCP_HDRLEN + 2)) | |
2276 | return; /* no header */ | |
2277 | dp = skb->data + 2; | |
2278 | ||
2279 | switch (CCP_CODE(dp)) { | |
2280 | case CCP_CONFREQ: | |
2281 | ||
6aa20a22 | 2282 | /* A ConfReq starts negotiation of compression |
1da177e4 LT |
2283 | * in one direction of transmission, |
2284 | * and hence brings it down...but which way? | |
2285 | * | |
2286 | * Remember: | |
2287 | * A ConfReq indicates what the sender would like to receive | |
2288 | */ | |
2289 | if(inbound) | |
2290 | /* He is proposing what I should send */ | |
2291 | ppp->xstate &= ~SC_COMP_RUN; | |
6aa20a22 | 2292 | else |
1da177e4 LT |
2293 | /* I am proposing to what he should send */ |
2294 | ppp->rstate &= ~SC_DECOMP_RUN; | |
6aa20a22 | 2295 | |
1da177e4 | 2296 | break; |
6aa20a22 | 2297 | |
1da177e4 LT |
2298 | case CCP_TERMREQ: |
2299 | case CCP_TERMACK: | |
2300 | /* | |
6aa20a22 | 2301 | * CCP is going down, both directions of transmission |
1da177e4 LT |
2302 | */ |
2303 | ppp->rstate &= ~SC_DECOMP_RUN; | |
2304 | ppp->xstate &= ~SC_COMP_RUN; | |
2305 | break; | |
2306 | ||
2307 | case CCP_CONFACK: | |
2308 | if ((ppp->flags & (SC_CCP_OPEN | SC_CCP_UP)) != SC_CCP_OPEN) | |
2309 | break; | |
2310 | len = CCP_LENGTH(dp); | |
2311 | if (!pskb_may_pull(skb, len + 2)) | |
2312 | return; /* too short */ | |
2313 | dp += CCP_HDRLEN; | |
2314 | len -= CCP_HDRLEN; | |
2315 | if (len < CCP_OPT_MINLEN || len < CCP_OPT_LENGTH(dp)) | |
2316 | break; | |
2317 | if (inbound) { | |
2318 | /* we will start receiving compressed packets */ | |
cd228d54 | 2319 | if (!ppp->rc_state) |
1da177e4 LT |
2320 | break; |
2321 | if (ppp->rcomp->decomp_init(ppp->rc_state, dp, len, | |
2322 | ppp->file.index, 0, ppp->mru, ppp->debug)) { | |
2323 | ppp->rstate |= SC_DECOMP_RUN; | |
2324 | ppp->rstate &= ~(SC_DC_ERROR | SC_DC_FERROR); | |
2325 | } | |
2326 | } else { | |
2327 | /* we will soon start sending compressed packets */ | |
cd228d54 | 2328 | if (!ppp->xc_state) |
1da177e4 LT |
2329 | break; |
2330 | if (ppp->xcomp->comp_init(ppp->xc_state, dp, len, | |
2331 | ppp->file.index, 0, ppp->debug)) | |
2332 | ppp->xstate |= SC_COMP_RUN; | |
2333 | } | |
2334 | break; | |
2335 | ||
2336 | case CCP_RESETACK: | |
2337 | /* reset the [de]compressor */ | |
2338 | if ((ppp->flags & SC_CCP_UP) == 0) | |
2339 | break; | |
2340 | if (inbound) { | |
2341 | if (ppp->rc_state && (ppp->rstate & SC_DECOMP_RUN)) { | |
2342 | ppp->rcomp->decomp_reset(ppp->rc_state); | |
2343 | ppp->rstate &= ~SC_DC_ERROR; | |
2344 | } | |
2345 | } else { | |
2346 | if (ppp->xc_state && (ppp->xstate & SC_COMP_RUN)) | |
2347 | ppp->xcomp->comp_reset(ppp->xc_state); | |
2348 | } | |
2349 | break; | |
2350 | } | |
2351 | } | |
2352 | ||
2353 | /* Free up compression resources. */ | |
2354 | static void | |
2355 | ppp_ccp_closed(struct ppp *ppp) | |
2356 | { | |
2357 | void *xstate, *rstate; | |
2358 | struct compressor *xcomp, *rcomp; | |
2359 | ||
2360 | ppp_lock(ppp); | |
2361 | ppp->flags &= ~(SC_CCP_OPEN | SC_CCP_UP); | |
2362 | ppp->xstate = 0; | |
2363 | xcomp = ppp->xcomp; | |
2364 | xstate = ppp->xc_state; | |
2365 | ppp->xc_state = NULL; | |
2366 | ppp->rstate = 0; | |
2367 | rcomp = ppp->rcomp; | |
2368 | rstate = ppp->rc_state; | |
2369 | ppp->rc_state = NULL; | |
2370 | ppp_unlock(ppp); | |
2371 | ||
2372 | if (xstate) { | |
2373 | xcomp->comp_free(xstate); | |
2374 | module_put(xcomp->owner); | |
2375 | } | |
2376 | if (rstate) { | |
2377 | rcomp->decomp_free(rstate); | |
2378 | module_put(rcomp->owner); | |
2379 | } | |
2380 | } | |
2381 | ||
2382 | /* List of compressors. */ | |
2383 | static LIST_HEAD(compressor_list); | |
2384 | static DEFINE_SPINLOCK(compressor_list_lock); | |
2385 | ||
2386 | struct compressor_entry { | |
2387 | struct list_head list; | |
2388 | struct compressor *comp; | |
2389 | }; | |
2390 | ||
2391 | static struct compressor_entry * | |
2392 | find_comp_entry(int proto) | |
2393 | { | |
2394 | struct compressor_entry *ce; | |
1da177e4 | 2395 | |
81616c5a | 2396 | list_for_each_entry(ce, &compressor_list, list) { |
1da177e4 LT |
2397 | if (ce->comp->compress_proto == proto) |
2398 | return ce; | |
2399 | } | |
2400 | return NULL; | |
2401 | } | |
2402 | ||
2403 | /* Register a compressor */ | |
2404 | int | |
2405 | ppp_register_compressor(struct compressor *cp) | |
2406 | { | |
2407 | struct compressor_entry *ce; | |
2408 | int ret; | |
2409 | spin_lock(&compressor_list_lock); | |
2410 | ret = -EEXIST; | |
cd228d54 | 2411 | if (find_comp_entry(cp->compress_proto)) |
1da177e4 LT |
2412 | goto out; |
2413 | ret = -ENOMEM; | |
2414 | ce = kmalloc(sizeof(struct compressor_entry), GFP_ATOMIC); | |
cd228d54 | 2415 | if (!ce) |
1da177e4 LT |
2416 | goto out; |
2417 | ret = 0; | |
2418 | ce->comp = cp; | |
2419 | list_add(&ce->list, &compressor_list); | |
2420 | out: | |
2421 | spin_unlock(&compressor_list_lock); | |
2422 | return ret; | |
2423 | } | |
2424 | ||
2425 | /* Unregister a compressor */ | |
2426 | void | |
2427 | ppp_unregister_compressor(struct compressor *cp) | |
2428 | { | |
2429 | struct compressor_entry *ce; | |
2430 | ||
2431 | spin_lock(&compressor_list_lock); | |
2432 | ce = find_comp_entry(cp->compress_proto); | |
cd228d54 | 2433 | if (ce && ce->comp == cp) { |
1da177e4 LT |
2434 | list_del(&ce->list); |
2435 | kfree(ce); | |
2436 | } | |
2437 | spin_unlock(&compressor_list_lock); | |
2438 | } | |
2439 | ||
2440 | /* Find a compressor. */ | |
2441 | static struct compressor * | |
2442 | find_compressor(int type) | |
2443 | { | |
2444 | struct compressor_entry *ce; | |
2445 | struct compressor *cp = NULL; | |
2446 | ||
2447 | spin_lock(&compressor_list_lock); | |
2448 | ce = find_comp_entry(type); | |
cd228d54 | 2449 | if (ce) { |
1da177e4 LT |
2450 | cp = ce->comp; |
2451 | if (!try_module_get(cp->owner)) | |
2452 | cp = NULL; | |
2453 | } | |
2454 | spin_unlock(&compressor_list_lock); | |
2455 | return cp; | |
2456 | } | |
2457 | ||
2458 | /* | |
2459 | * Miscelleneous stuff. | |
2460 | */ | |
2461 | ||
2462 | static void | |
2463 | ppp_get_stats(struct ppp *ppp, struct ppp_stats *st) | |
2464 | { | |
2465 | struct slcompress *vj = ppp->vj; | |
2466 | ||
2467 | memset(st, 0, sizeof(*st)); | |
8c0469cd PZ |
2468 | st->p.ppp_ipackets = ppp->dev->stats.rx_packets; |
2469 | st->p.ppp_ierrors = ppp->dev->stats.rx_errors; | |
2470 | st->p.ppp_ibytes = ppp->dev->stats.rx_bytes; | |
2471 | st->p.ppp_opackets = ppp->dev->stats.tx_packets; | |
2472 | st->p.ppp_oerrors = ppp->dev->stats.tx_errors; | |
2473 | st->p.ppp_obytes = ppp->dev->stats.tx_bytes; | |
cd228d54 | 2474 | if (!vj) |
1da177e4 LT |
2475 | return; |
2476 | st->vj.vjs_packets = vj->sls_o_compressed + vj->sls_o_uncompressed; | |
2477 | st->vj.vjs_compressed = vj->sls_o_compressed; | |
2478 | st->vj.vjs_searches = vj->sls_o_searches; | |
2479 | st->vj.vjs_misses = vj->sls_o_misses; | |
2480 | st->vj.vjs_errorin = vj->sls_i_error; | |
2481 | st->vj.vjs_tossed = vj->sls_i_tossed; | |
2482 | st->vj.vjs_uncompressedin = vj->sls_i_uncompressed; | |
2483 | st->vj.vjs_compressedin = vj->sls_i_compressed; | |
2484 | } | |
2485 | ||
2486 | /* | |
2487 | * Stuff for handling the lists of ppp units and channels | |
2488 | * and for initialization. | |
2489 | */ | |
2490 | ||
2491 | /* | |
2492 | * Create a new ppp interface unit. Fails if it can't allocate memory | |
2493 | * or if there is already a unit with the requested number. | |
2494 | * unit == -1 means allocate a new number. | |
2495 | */ | |
2496 | static struct ppp * | |
273ec51d | 2497 | ppp_create_interface(struct net *net, int unit, int *retp) |
1da177e4 LT |
2498 | { |
2499 | struct ppp *ppp; | |
273ec51d | 2500 | struct ppp_net *pn; |
1da177e4 LT |
2501 | struct net_device *dev = NULL; |
2502 | int ret = -ENOMEM; | |
2503 | int i; | |
2504 | ||
c8019bf3 | 2505 | dev = alloc_netdev(sizeof(struct ppp), "", ppp_setup); |
1da177e4 LT |
2506 | if (!dev) |
2507 | goto out1; | |
1da177e4 | 2508 | |
273ec51d CG |
2509 | pn = ppp_pernet(net); |
2510 | ||
c8019bf3 WC |
2511 | ppp = netdev_priv(dev); |
2512 | ppp->dev = dev; | |
1da177e4 LT |
2513 | ppp->mru = PPP_MRU; |
2514 | init_ppp_file(&ppp->file, INTERFACE); | |
2515 | ppp->file.hdrlen = PPP_HDRLEN - 2; /* don't count proto bytes */ | |
2516 | for (i = 0; i < NUM_NP; ++i) | |
2517 | ppp->npmode[i] = NPMODE_PASS; | |
2518 | INIT_LIST_HEAD(&ppp->channels); | |
2519 | spin_lock_init(&ppp->rlock); | |
2520 | spin_lock_init(&ppp->wlock); | |
2521 | #ifdef CONFIG_PPP_MULTILINK | |
2522 | ppp->minseq = -1; | |
2523 | skb_queue_head_init(&ppp->mrq); | |
2524 | #endif /* CONFIG_PPP_MULTILINK */ | |
1da177e4 | 2525 | |
273ec51d CG |
2526 | /* |
2527 | * drum roll: don't forget to set | |
2528 | * the net device is belong to | |
2529 | */ | |
2530 | dev_net_set(dev, net); | |
2531 | ||
1da177e4 | 2532 | ret = -EEXIST; |
273ec51d | 2533 | mutex_lock(&pn->all_ppp_mutex); |
7a95d267 CG |
2534 | |
2535 | if (unit < 0) { | |
273ec51d | 2536 | unit = unit_get(&pn->units_idr, ppp); |
7a95d267 CG |
2537 | if (unit < 0) { |
2538 | *retp = unit; | |
2539 | goto out2; | |
2540 | } | |
2541 | } else { | |
273ec51d | 2542 | if (unit_find(&pn->units_idr, unit)) |
7a95d267 | 2543 | goto out2; /* unit already exists */ |
85997576 CG |
2544 | /* |
2545 | * if caller need a specified unit number | |
2546 | * lets try to satisfy him, otherwise -- | |
2547 | * he should better ask us for new unit number | |
2548 | * | |
2549 | * NOTE: yes I know that returning EEXIST it's not | |
2550 | * fair but at least pppd will ask us to allocate | |
2551 | * new unit in this case so user is happy :) | |
2552 | */ | |
273ec51d | 2553 | unit = unit_set(&pn->units_idr, ppp, unit); |
85997576 | 2554 | if (unit < 0) |
7a95d267 | 2555 | goto out2; |
7a95d267 | 2556 | } |
1da177e4 LT |
2557 | |
2558 | /* Initialize the new ppp unit */ | |
2559 | ppp->file.index = unit; | |
2560 | sprintf(dev->name, "ppp%d", unit); | |
2561 | ||
2562 | ret = register_netdev(dev); | |
2563 | if (ret != 0) { | |
273ec51d | 2564 | unit_put(&pn->units_idr, unit); |
1da177e4 LT |
2565 | printk(KERN_ERR "PPP: couldn't register device %s (%d)\n", |
2566 | dev->name, ret); | |
2567 | goto out2; | |
2568 | } | |
2569 | ||
273ec51d CG |
2570 | ppp->ppp_net = net; |
2571 | ||
1da177e4 | 2572 | atomic_inc(&ppp_unit_count); |
273ec51d | 2573 | mutex_unlock(&pn->all_ppp_mutex); |
7a95d267 | 2574 | |
1da177e4 LT |
2575 | *retp = 0; |
2576 | return ppp; | |
2577 | ||
2578 | out2: | |
273ec51d | 2579 | mutex_unlock(&pn->all_ppp_mutex); |
1da177e4 LT |
2580 | free_netdev(dev); |
2581 | out1: | |
1da177e4 LT |
2582 | *retp = ret; |
2583 | return NULL; | |
2584 | } | |
2585 | ||
2586 | /* | |
2587 | * Initialize a ppp_file structure. | |
2588 | */ | |
2589 | static void | |
2590 | init_ppp_file(struct ppp_file *pf, int kind) | |
2591 | { | |
2592 | pf->kind = kind; | |
2593 | skb_queue_head_init(&pf->xq); | |
2594 | skb_queue_head_init(&pf->rq); | |
2595 | atomic_set(&pf->refcnt, 1); | |
2596 | init_waitqueue_head(&pf->rwait); | |
2597 | } | |
2598 | ||
2599 | /* | |
2600 | * Take down a ppp interface unit - called when the owning file | |
2601 | * (the one that created the unit) is closed or detached. | |
2602 | */ | |
2603 | static void ppp_shutdown_interface(struct ppp *ppp) | |
2604 | { | |
273ec51d CG |
2605 | struct ppp_net *pn; |
2606 | ||
2607 | pn = ppp_pernet(ppp->ppp_net); | |
2608 | mutex_lock(&pn->all_ppp_mutex); | |
2609 | ||
1da177e4 | 2610 | /* This will call dev_close() for us. */ |
739840d5 JC |
2611 | ppp_lock(ppp); |
2612 | if (!ppp->closing) { | |
2613 | ppp->closing = 1; | |
2614 | ppp_unlock(ppp); | |
2615 | unregister_netdev(ppp->dev); | |
2616 | } else | |
2617 | ppp_unlock(ppp); | |
2618 | ||
273ec51d | 2619 | unit_put(&pn->units_idr, ppp->file.index); |
1da177e4 LT |
2620 | ppp->file.dead = 1; |
2621 | ppp->owner = NULL; | |
2622 | wake_up_interruptible(&ppp->file.rwait); | |
273ec51d CG |
2623 | |
2624 | mutex_unlock(&pn->all_ppp_mutex); | |
1da177e4 LT |
2625 | } |
2626 | ||
2627 | /* | |
2628 | * Free the memory used by a ppp unit. This is only called once | |
2629 | * there are no channels connected to the unit and no file structs | |
2630 | * that reference the unit. | |
2631 | */ | |
2632 | static void ppp_destroy_interface(struct ppp *ppp) | |
2633 | { | |
2634 | atomic_dec(&ppp_unit_count); | |
2635 | ||
2636 | if (!ppp->file.dead || ppp->n_channels) { | |
2637 | /* "can't happen" */ | |
2638 | printk(KERN_ERR "ppp: destroying ppp struct %p but dead=%d " | |
2639 | "n_channels=%d !\n", ppp, ppp->file.dead, | |
2640 | ppp->n_channels); | |
2641 | return; | |
2642 | } | |
2643 | ||
2644 | ppp_ccp_closed(ppp); | |
2645 | if (ppp->vj) { | |
2646 | slhc_free(ppp->vj); | |
2647 | ppp->vj = NULL; | |
2648 | } | |
2649 | skb_queue_purge(&ppp->file.xq); | |
2650 | skb_queue_purge(&ppp->file.rq); | |
2651 | #ifdef CONFIG_PPP_MULTILINK | |
2652 | skb_queue_purge(&ppp->mrq); | |
2653 | #endif /* CONFIG_PPP_MULTILINK */ | |
2654 | #ifdef CONFIG_PPP_FILTER | |
96edf83c JJ |
2655 | kfree(ppp->pass_filter); |
2656 | ppp->pass_filter = NULL; | |
2657 | kfree(ppp->active_filter); | |
2658 | ppp->active_filter = NULL; | |
1da177e4 LT |
2659 | #endif /* CONFIG_PPP_FILTER */ |
2660 | ||
165de5b7 L |
2661 | if (ppp->xmit_pending) |
2662 | kfree_skb(ppp->xmit_pending); | |
2663 | ||
739840d5 | 2664 | free_netdev(ppp->dev); |
1da177e4 LT |
2665 | } |
2666 | ||
2667 | /* | |
2668 | * Locate an existing ppp unit. | |
8ed965d6 | 2669 | * The caller should have locked the all_ppp_mutex. |
1da177e4 LT |
2670 | */ |
2671 | static struct ppp * | |
273ec51d | 2672 | ppp_find_unit(struct ppp_net *pn, int unit) |
1da177e4 | 2673 | { |
273ec51d | 2674 | return unit_find(&pn->units_idr, unit); |
1da177e4 LT |
2675 | } |
2676 | ||
2677 | /* | |
2678 | * Locate an existing ppp channel. | |
2679 | * The caller should have locked the all_channels_lock. | |
2680 | * First we look in the new_channels list, then in the | |
2681 | * all_channels list. If found in the new_channels list, | |
2682 | * we move it to the all_channels list. This is for speed | |
2683 | * when we have a lot of channels in use. | |
2684 | */ | |
2685 | static struct channel * | |
273ec51d | 2686 | ppp_find_channel(struct ppp_net *pn, int unit) |
1da177e4 LT |
2687 | { |
2688 | struct channel *pch; | |
1da177e4 | 2689 | |
273ec51d | 2690 | list_for_each_entry(pch, &pn->new_channels, list) { |
1da177e4 | 2691 | if (pch->file.index == unit) { |
273ec51d | 2692 | list_move(&pch->list, &pn->all_channels); |
1da177e4 LT |
2693 | return pch; |
2694 | } | |
2695 | } | |
273ec51d CG |
2696 | |
2697 | list_for_each_entry(pch, &pn->all_channels, list) { | |
1da177e4 LT |
2698 | if (pch->file.index == unit) |
2699 | return pch; | |
2700 | } | |
273ec51d | 2701 | |
1da177e4 LT |
2702 | return NULL; |
2703 | } | |
2704 | ||
2705 | /* | |
2706 | * Connect a PPP channel to a PPP interface unit. | |
2707 | */ | |
2708 | static int | |
2709 | ppp_connect_channel(struct channel *pch, int unit) | |
2710 | { | |
2711 | struct ppp *ppp; | |
273ec51d | 2712 | struct ppp_net *pn; |
1da177e4 LT |
2713 | int ret = -ENXIO; |
2714 | int hdrlen; | |
2715 | ||
273ec51d CG |
2716 | pn = ppp_pernet(pch->chan_net); |
2717 | ||
2718 | mutex_lock(&pn->all_ppp_mutex); | |
2719 | ppp = ppp_find_unit(pn, unit); | |
cd228d54 | 2720 | if (!ppp) |
1da177e4 LT |
2721 | goto out; |
2722 | write_lock_bh(&pch->upl); | |
2723 | ret = -EINVAL; | |
cd228d54 | 2724 | if (pch->ppp) |
1da177e4 LT |
2725 | goto outl; |
2726 | ||
2727 | ppp_lock(ppp); | |
2728 | if (pch->file.hdrlen > ppp->file.hdrlen) | |
2729 | ppp->file.hdrlen = pch->file.hdrlen; | |
2730 | hdrlen = pch->file.hdrlen + 2; /* for protocol bytes */ | |
739840d5 | 2731 | if (hdrlen > ppp->dev->hard_header_len) |
1da177e4 LT |
2732 | ppp->dev->hard_header_len = hdrlen; |
2733 | list_add_tail(&pch->clist, &ppp->channels); | |
2734 | ++ppp->n_channels; | |
2735 | pch->ppp = ppp; | |
2736 | atomic_inc(&ppp->file.refcnt); | |
2737 | ppp_unlock(ppp); | |
2738 | ret = 0; | |
2739 | ||
2740 | outl: | |
2741 | write_unlock_bh(&pch->upl); | |
2742 | out: | |
273ec51d | 2743 | mutex_unlock(&pn->all_ppp_mutex); |
1da177e4 LT |
2744 | return ret; |
2745 | } | |
2746 | ||
2747 | /* | |
2748 | * Disconnect a channel from its ppp unit. | |
2749 | */ | |
2750 | static int | |
2751 | ppp_disconnect_channel(struct channel *pch) | |
2752 | { | |
2753 | struct ppp *ppp; | |
2754 | int err = -EINVAL; | |
2755 | ||
2756 | write_lock_bh(&pch->upl); | |
2757 | ppp = pch->ppp; | |
2758 | pch->ppp = NULL; | |
2759 | write_unlock_bh(&pch->upl); | |
cd228d54 | 2760 | if (ppp) { |
1da177e4 LT |
2761 | /* remove it from the ppp unit's list */ |
2762 | ppp_lock(ppp); | |
2763 | list_del(&pch->clist); | |
2764 | if (--ppp->n_channels == 0) | |
2765 | wake_up_interruptible(&ppp->file.rwait); | |
2766 | ppp_unlock(ppp); | |
2767 | if (atomic_dec_and_test(&ppp->file.refcnt)) | |
2768 | ppp_destroy_interface(ppp); | |
2769 | err = 0; | |
2770 | } | |
2771 | return err; | |
2772 | } | |
2773 | ||
2774 | /* | |
2775 | * Free up the resources used by a ppp channel. | |
2776 | */ | |
2777 | static void ppp_destroy_channel(struct channel *pch) | |
2778 | { | |
2779 | atomic_dec(&channel_count); | |
2780 | ||
2781 | if (!pch->file.dead) { | |
2782 | /* "can't happen" */ | |
2783 | printk(KERN_ERR "ppp: destroying undead channel %p !\n", | |
2784 | pch); | |
2785 | return; | |
2786 | } | |
2787 | skb_queue_purge(&pch->file.xq); | |
2788 | skb_queue_purge(&pch->file.rq); | |
2789 | kfree(pch); | |
2790 | } | |
2791 | ||
2792 | static void __exit ppp_cleanup(void) | |
2793 | { | |
2794 | /* should never happen */ | |
2795 | if (atomic_read(&ppp_unit_count) || atomic_read(&channel_count)) | |
2796 | printk(KERN_ERR "PPP: removing module but units remain!\n"); | |
68fc4fab | 2797 | unregister_chrdev(PPP_MAJOR, "ppp"); |
9a6a2a5e | 2798 | device_destroy(ppp_class, MKDEV(PPP_MAJOR, 0)); |
56b22935 | 2799 | class_destroy(ppp_class); |
273ec51d | 2800 | unregister_pernet_gen_device(ppp_net_id, &ppp_net_ops); |
1da177e4 LT |
2801 | } |
2802 | ||
2803 | /* | |
7a95d267 CG |
2804 | * Units handling. Caller must protect concurrent access |
2805 | * by holding all_ppp_mutex | |
1da177e4 | 2806 | */ |
7a95d267 | 2807 | |
85997576 CG |
2808 | /* associate pointer with specified number */ |
2809 | static int unit_set(struct idr *p, void *ptr, int n) | |
2810 | { | |
2811 | int unit, err; | |
2812 | ||
2813 | again: | |
2814 | if (!idr_pre_get(p, GFP_KERNEL)) { | |
2815 | printk(KERN_ERR "PPP: No free memory for idr\n"); | |
2816 | return -ENOMEM; | |
2817 | } | |
2818 | ||
2819 | err = idr_get_new_above(p, ptr, n, &unit); | |
2820 | if (err == -EAGAIN) | |
2821 | goto again; | |
2822 | ||
2823 | if (unit != n) { | |
2824 | idr_remove(p, unit); | |
2825 | return -EINVAL; | |
2826 | } | |
2827 | ||
2828 | return unit; | |
2829 | } | |
2830 | ||
7a95d267 CG |
2831 | /* get new free unit number and associate pointer with it */ |
2832 | static int unit_get(struct idr *p, void *ptr) | |
1da177e4 | 2833 | { |
7a95d267 | 2834 | int unit, err; |
1da177e4 | 2835 | |
7a95d267 | 2836 | again: |
85997576 CG |
2837 | if (!idr_pre_get(p, GFP_KERNEL)) { |
2838 | printk(KERN_ERR "PPP: No free memory for idr\n"); | |
7a95d267 | 2839 | return -ENOMEM; |
1da177e4 | 2840 | } |
1da177e4 | 2841 | |
7a95d267 CG |
2842 | err = idr_get_new_above(p, ptr, 0, &unit); |
2843 | if (err == -EAGAIN) | |
2844 | goto again; | |
1da177e4 | 2845 | |
7a95d267 | 2846 | return unit; |
1da177e4 LT |
2847 | } |
2848 | ||
7a95d267 CG |
2849 | /* put unit number back to a pool */ |
2850 | static void unit_put(struct idr *p, int n) | |
1da177e4 | 2851 | { |
7a95d267 | 2852 | idr_remove(p, n); |
1da177e4 LT |
2853 | } |
2854 | ||
7a95d267 CG |
2855 | /* get pointer associated with the number */ |
2856 | static void *unit_find(struct idr *p, int n) | |
1da177e4 | 2857 | { |
7a95d267 | 2858 | return idr_find(p, n); |
1da177e4 LT |
2859 | } |
2860 | ||
2861 | /* Module/initialization stuff */ | |
2862 | ||
2863 | module_init(ppp_init); | |
2864 | module_exit(ppp_cleanup); | |
2865 | ||
273ec51d | 2866 | EXPORT_SYMBOL(ppp_register_net_channel); |
1da177e4 LT |
2867 | EXPORT_SYMBOL(ppp_register_channel); |
2868 | EXPORT_SYMBOL(ppp_unregister_channel); | |
2869 | EXPORT_SYMBOL(ppp_channel_index); | |
2870 | EXPORT_SYMBOL(ppp_unit_number); | |
2871 | EXPORT_SYMBOL(ppp_input); | |
2872 | EXPORT_SYMBOL(ppp_input_error); | |
2873 | EXPORT_SYMBOL(ppp_output_wakeup); | |
2874 | EXPORT_SYMBOL(ppp_register_compressor); | |
2875 | EXPORT_SYMBOL(ppp_unregister_compressor); | |
2876 | MODULE_LICENSE("GPL"); | |
2877 | MODULE_ALIAS_CHARDEV_MAJOR(PPP_MAJOR); | |
2878 | MODULE_ALIAS("/dev/ppp"); |