Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Generic PPP layer for Linux. |
| 3 | * |
| 4 | * Copyright 1999-2002 Paul Mackerras. |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU General Public License |
| 8 | * as published by the Free Software Foundation; either version |
| 9 | * 2 of the License, or (at your option) any later version. |
| 10 | * |
| 11 | * The generic PPP layer handles the PPP network interfaces, the |
| 12 | * /dev/ppp device, packet and VJ compression, and multilink. |
| 13 | * It talks to PPP `channels' via the interface defined in |
| 14 | * include/linux/ppp_channel.h. Channels provide the basic means for |
| 15 | * sending and receiving PPP frames on some kind of communications |
| 16 | * channel. |
| 17 | * |
| 18 | * Part of the code in this driver was inspired by the old async-only |
| 19 | * PPP driver, written by Michael Callahan and Al Longyear, and |
| 20 | * subsequently hacked by Paul Mackerras. |
| 21 | * |
| 22 | * ==FILEVERSION 20041108== |
| 23 | */ |
| 24 | |
| 25 | #include <linux/config.h> |
| 26 | #include <linux/module.h> |
| 27 | #include <linux/kernel.h> |
| 28 | #include <linux/kmod.h> |
| 29 | #include <linux/init.h> |
| 30 | #include <linux/list.h> |
| 31 | #include <linux/devfs_fs_kernel.h> |
| 32 | #include <linux/netdevice.h> |
| 33 | #include <linux/poll.h> |
| 34 | #include <linux/ppp_defs.h> |
| 35 | #include <linux/filter.h> |
| 36 | #include <linux/if_ppp.h> |
| 37 | #include <linux/ppp_channel.h> |
| 38 | #include <linux/ppp-comp.h> |
| 39 | #include <linux/skbuff.h> |
| 40 | #include <linux/rtnetlink.h> |
| 41 | #include <linux/if_arp.h> |
| 42 | #include <linux/ip.h> |
| 43 | #include <linux/tcp.h> |
| 44 | #include <linux/spinlock.h> |
| 45 | #include <linux/smp_lock.h> |
| 46 | #include <linux/rwsem.h> |
| 47 | #include <linux/stddef.h> |
| 48 | #include <linux/device.h> |
Arjan van de Ven | 8ed965d | 2006-03-23 03:00:21 -0800 | [diff] [blame] | 49 | #include <linux/mutex.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 50 | #include <net/slhc_vj.h> |
| 51 | #include <asm/atomic.h> |
| 52 | |
| 53 | #define PPP_VERSION "2.4.2" |
| 54 | |
| 55 | /* |
| 56 | * Network protocols we support. |
| 57 | */ |
| 58 | #define NP_IP 0 /* Internet Protocol V4 */ |
| 59 | #define NP_IPV6 1 /* Internet Protocol V6 */ |
| 60 | #define NP_IPX 2 /* IPX protocol */ |
| 61 | #define NP_AT 3 /* Appletalk protocol */ |
| 62 | #define NP_MPLS_UC 4 /* MPLS unicast */ |
| 63 | #define NP_MPLS_MC 5 /* MPLS multicast */ |
| 64 | #define NUM_NP 6 /* Number of NPs. */ |
| 65 | |
| 66 | #define MPHDRLEN 6 /* multilink protocol header length */ |
| 67 | #define MPHDRLEN_SSN 4 /* ditto with short sequence numbers */ |
| 68 | #define MIN_FRAG_SIZE 64 |
| 69 | |
| 70 | /* |
| 71 | * An instance of /dev/ppp can be associated with either a ppp |
| 72 | * interface unit or a ppp channel. In both cases, file->private_data |
| 73 | * points to one of these. |
| 74 | */ |
| 75 | struct ppp_file { |
| 76 | enum { |
| 77 | INTERFACE=1, CHANNEL |
| 78 | } kind; |
| 79 | struct sk_buff_head xq; /* pppd transmit queue */ |
| 80 | struct sk_buff_head rq; /* receive queue for pppd */ |
| 81 | wait_queue_head_t rwait; /* for poll on reading /dev/ppp */ |
| 82 | atomic_t refcnt; /* # refs (incl /dev/ppp attached) */ |
| 83 | int hdrlen; /* space to leave for headers */ |
| 84 | int index; /* interface unit / channel number */ |
| 85 | int dead; /* unit/channel has been shut down */ |
| 86 | }; |
| 87 | |
| 88 | #define PF_TO_X(pf, X) ((X *)((char *)(pf) - offsetof(X, file))) |
| 89 | |
| 90 | #define PF_TO_PPP(pf) PF_TO_X(pf, struct ppp) |
| 91 | #define PF_TO_CHANNEL(pf) PF_TO_X(pf, struct channel) |
| 92 | |
| 93 | #define ROUNDUP(n, x) (((n) + (x) - 1) / (x)) |
| 94 | |
| 95 | /* |
| 96 | * Data structure describing one ppp unit. |
| 97 | * A ppp unit corresponds to a ppp network interface device |
| 98 | * and represents a multilink bundle. |
| 99 | * It can have 0 or more ppp channels connected to it. |
| 100 | */ |
| 101 | struct ppp { |
| 102 | struct ppp_file file; /* stuff for read/write/poll 0 */ |
| 103 | struct file *owner; /* file that owns this unit 48 */ |
| 104 | struct list_head channels; /* list of attached channels 4c */ |
| 105 | int n_channels; /* how many channels are attached 54 */ |
| 106 | spinlock_t rlock; /* lock for receive side 58 */ |
| 107 | spinlock_t wlock; /* lock for transmit side 5c */ |
| 108 | int mru; /* max receive unit 60 */ |
| 109 | unsigned int flags; /* control bits 64 */ |
| 110 | unsigned int xstate; /* transmit state bits 68 */ |
| 111 | unsigned int rstate; /* receive state bits 6c */ |
| 112 | int debug; /* debug flags 70 */ |
| 113 | struct slcompress *vj; /* state for VJ header compression */ |
| 114 | enum NPmode npmode[NUM_NP]; /* what to do with each net proto 78 */ |
| 115 | struct sk_buff *xmit_pending; /* a packet ready to go out 88 */ |
| 116 | struct compressor *xcomp; /* transmit packet compressor 8c */ |
| 117 | void *xc_state; /* its internal state 90 */ |
| 118 | struct compressor *rcomp; /* receive decompressor 94 */ |
| 119 | void *rc_state; /* its internal state 98 */ |
| 120 | unsigned long last_xmit; /* jiffies when last pkt sent 9c */ |
| 121 | unsigned long last_recv; /* jiffies when last pkt rcvd a0 */ |
| 122 | struct net_device *dev; /* network interface device a4 */ |
| 123 | #ifdef CONFIG_PPP_MULTILINK |
| 124 | int nxchan; /* next channel to send something on */ |
| 125 | u32 nxseq; /* next sequence number to send */ |
| 126 | int mrru; /* MP: max reconst. receive unit */ |
| 127 | u32 nextseq; /* MP: seq no of next packet */ |
| 128 | u32 minseq; /* MP: min of most recent seqnos */ |
| 129 | struct sk_buff_head mrq; /* MP: receive reconstruction queue */ |
| 130 | #endif /* CONFIG_PPP_MULTILINK */ |
| 131 | struct net_device_stats stats; /* statistics */ |
| 132 | #ifdef CONFIG_PPP_FILTER |
| 133 | struct sock_filter *pass_filter; /* filter for packets to pass */ |
| 134 | struct sock_filter *active_filter;/* filter for pkts to reset idle */ |
| 135 | unsigned pass_len, active_len; |
| 136 | #endif /* CONFIG_PPP_FILTER */ |
| 137 | }; |
| 138 | |
| 139 | /* |
| 140 | * Bits in flags: SC_NO_TCP_CCID, SC_CCP_OPEN, SC_CCP_UP, SC_LOOP_TRAFFIC, |
Matt Domsch | b3f9b92 | 2005-11-08 09:40:47 -0800 | [diff] [blame] | 141 | * SC_MULTILINK, SC_MP_SHORTSEQ, SC_MP_XSHORTSEQ, SC_COMP_TCP, SC_REJ_COMP_TCP, |
| 142 | * SC_MUST_COMP |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 143 | * Bits in rstate: SC_DECOMP_RUN, SC_DC_ERROR, SC_DC_FERROR. |
| 144 | * Bits in xstate: SC_COMP_RUN |
| 145 | */ |
| 146 | #define SC_FLAG_BITS (SC_NO_TCP_CCID|SC_CCP_OPEN|SC_CCP_UP|SC_LOOP_TRAFFIC \ |
| 147 | |SC_MULTILINK|SC_MP_SHORTSEQ|SC_MP_XSHORTSEQ \ |
Matt Domsch | b3f9b92 | 2005-11-08 09:40:47 -0800 | [diff] [blame] | 148 | |SC_COMP_TCP|SC_REJ_COMP_TCP|SC_MUST_COMP) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 149 | |
| 150 | /* |
| 151 | * Private data structure for each channel. |
| 152 | * This includes the data structure used for multilink. |
| 153 | */ |
| 154 | struct channel { |
| 155 | struct ppp_file file; /* stuff for read/write/poll */ |
| 156 | struct list_head list; /* link in all/new_channels list */ |
| 157 | struct ppp_channel *chan; /* public channel data structure */ |
| 158 | struct rw_semaphore chan_sem; /* protects `chan' during chan ioctl */ |
| 159 | spinlock_t downl; /* protects `chan', file.xq dequeue */ |
| 160 | struct ppp *ppp; /* ppp unit we're connected to */ |
| 161 | struct list_head clist; /* link in list of channels per unit */ |
| 162 | rwlock_t upl; /* protects `ppp' */ |
| 163 | #ifdef CONFIG_PPP_MULTILINK |
| 164 | u8 avail; /* flag used in multilink stuff */ |
| 165 | u8 had_frag; /* >= 1 fragments have been sent */ |
| 166 | u32 lastseq; /* MP: last sequence # received */ |
| 167 | #endif /* CONFIG_PPP_MULTILINK */ |
| 168 | }; |
| 169 | |
| 170 | /* |
| 171 | * SMP locking issues: |
| 172 | * Both the ppp.rlock and ppp.wlock locks protect the ppp.channels |
| 173 | * list and the ppp.n_channels field, you need to take both locks |
| 174 | * before you modify them. |
| 175 | * The lock ordering is: channel.upl -> ppp.wlock -> ppp.rlock -> |
| 176 | * channel.downl. |
| 177 | */ |
| 178 | |
| 179 | /* |
| 180 | * A cardmap represents a mapping from unsigned integers to pointers, |
| 181 | * and provides a fast "find lowest unused number" operation. |
| 182 | * It uses a broad (32-way) tree with a bitmap at each level. |
| 183 | * It is designed to be space-efficient for small numbers of entries |
| 184 | * and time-efficient for large numbers of entries. |
| 185 | */ |
| 186 | #define CARDMAP_ORDER 5 |
| 187 | #define CARDMAP_WIDTH (1U << CARDMAP_ORDER) |
| 188 | #define CARDMAP_MASK (CARDMAP_WIDTH - 1) |
| 189 | |
| 190 | struct cardmap { |
| 191 | int shift; |
| 192 | unsigned long inuse; |
| 193 | struct cardmap *parent; |
| 194 | void *ptr[CARDMAP_WIDTH]; |
| 195 | }; |
| 196 | static void *cardmap_get(struct cardmap *map, unsigned int nr); |
| 197 | static void cardmap_set(struct cardmap **map, unsigned int nr, void *ptr); |
| 198 | static unsigned int cardmap_find_first_free(struct cardmap *map); |
| 199 | static void cardmap_destroy(struct cardmap **map); |
| 200 | |
| 201 | /* |
Arjan van de Ven | 8ed965d | 2006-03-23 03:00:21 -0800 | [diff] [blame] | 202 | * all_ppp_mutex protects the all_ppp_units mapping. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 203 | * It also ensures that finding a ppp unit in the all_ppp_units map |
| 204 | * and updating its file.refcnt field is atomic. |
| 205 | */ |
Arjan van de Ven | 8ed965d | 2006-03-23 03:00:21 -0800 | [diff] [blame] | 206 | static DEFINE_MUTEX(all_ppp_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 207 | static struct cardmap *all_ppp_units; |
| 208 | static atomic_t ppp_unit_count = ATOMIC_INIT(0); |
| 209 | |
| 210 | /* |
| 211 | * all_channels_lock protects all_channels and last_channel_index, |
| 212 | * and the atomicity of find a channel and updating its file.refcnt |
| 213 | * field. |
| 214 | */ |
| 215 | static DEFINE_SPINLOCK(all_channels_lock); |
| 216 | static LIST_HEAD(all_channels); |
| 217 | static LIST_HEAD(new_channels); |
| 218 | static int last_channel_index; |
| 219 | static atomic_t channel_count = ATOMIC_INIT(0); |
| 220 | |
| 221 | /* Get the PPP protocol number from a skb */ |
| 222 | #define PPP_PROTO(skb) (((skb)->data[0] << 8) + (skb)->data[1]) |
| 223 | |
| 224 | /* We limit the length of ppp->file.rq to this (arbitrary) value */ |
| 225 | #define PPP_MAX_RQLEN 32 |
| 226 | |
| 227 | /* |
| 228 | * Maximum number of multilink fragments queued up. |
| 229 | * This has to be large enough to cope with the maximum latency of |
| 230 | * the slowest channel relative to the others. Strictly it should |
| 231 | * depend on the number of channels and their characteristics. |
| 232 | */ |
| 233 | #define PPP_MP_MAX_QLEN 128 |
| 234 | |
| 235 | /* Multilink header bits. */ |
| 236 | #define B 0x80 /* this fragment begins a packet */ |
| 237 | #define E 0x40 /* this fragment ends a packet */ |
| 238 | |
| 239 | /* Compare multilink sequence numbers (assumed to be 32 bits wide) */ |
| 240 | #define seq_before(a, b) ((s32)((a) - (b)) < 0) |
| 241 | #define seq_after(a, b) ((s32)((a) - (b)) > 0) |
| 242 | |
| 243 | /* Prototypes. */ |
| 244 | static int ppp_unattached_ioctl(struct ppp_file *pf, struct file *file, |
| 245 | unsigned int cmd, unsigned long arg); |
| 246 | static void ppp_xmit_process(struct ppp *ppp); |
| 247 | static void ppp_send_frame(struct ppp *ppp, struct sk_buff *skb); |
| 248 | static void ppp_push(struct ppp *ppp); |
| 249 | static void ppp_channel_push(struct channel *pch); |
| 250 | static void ppp_receive_frame(struct ppp *ppp, struct sk_buff *skb, |
| 251 | struct channel *pch); |
| 252 | static void ppp_receive_error(struct ppp *ppp); |
| 253 | static void ppp_receive_nonmp_frame(struct ppp *ppp, struct sk_buff *skb); |
| 254 | static struct sk_buff *ppp_decompress_frame(struct ppp *ppp, |
| 255 | struct sk_buff *skb); |
| 256 | #ifdef CONFIG_PPP_MULTILINK |
| 257 | static void ppp_receive_mp_frame(struct ppp *ppp, struct sk_buff *skb, |
| 258 | struct channel *pch); |
| 259 | static void ppp_mp_insert(struct ppp *ppp, struct sk_buff *skb); |
| 260 | static struct sk_buff *ppp_mp_reconstruct(struct ppp *ppp); |
| 261 | static int ppp_mp_explode(struct ppp *ppp, struct sk_buff *skb); |
| 262 | #endif /* CONFIG_PPP_MULTILINK */ |
| 263 | static int ppp_set_compress(struct ppp *ppp, unsigned long arg); |
| 264 | static void ppp_ccp_peek(struct ppp *ppp, struct sk_buff *skb, int inbound); |
| 265 | static void ppp_ccp_closed(struct ppp *ppp); |
| 266 | static struct compressor *find_compressor(int type); |
| 267 | static void ppp_get_stats(struct ppp *ppp, struct ppp_stats *st); |
| 268 | static struct ppp *ppp_create_interface(int unit, int *retp); |
| 269 | static void init_ppp_file(struct ppp_file *pf, int kind); |
| 270 | static void ppp_shutdown_interface(struct ppp *ppp); |
| 271 | static void ppp_destroy_interface(struct ppp *ppp); |
| 272 | static struct ppp *ppp_find_unit(int unit); |
| 273 | static struct channel *ppp_find_channel(int unit); |
| 274 | static int ppp_connect_channel(struct channel *pch, int unit); |
| 275 | static int ppp_disconnect_channel(struct channel *pch); |
| 276 | static void ppp_destroy_channel(struct channel *pch); |
| 277 | |
gregkh@suse.de | 56b2293 | 2005-03-23 10:01:41 -0800 | [diff] [blame] | 278 | static struct class *ppp_class; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 279 | |
| 280 | /* Translates a PPP protocol number to a NP index (NP == network protocol) */ |
| 281 | static inline int proto_to_npindex(int proto) |
| 282 | { |
| 283 | switch (proto) { |
| 284 | case PPP_IP: |
| 285 | return NP_IP; |
| 286 | case PPP_IPV6: |
| 287 | return NP_IPV6; |
| 288 | case PPP_IPX: |
| 289 | return NP_IPX; |
| 290 | case PPP_AT: |
| 291 | return NP_AT; |
| 292 | case PPP_MPLS_UC: |
| 293 | return NP_MPLS_UC; |
| 294 | case PPP_MPLS_MC: |
| 295 | return NP_MPLS_MC; |
| 296 | } |
| 297 | return -EINVAL; |
| 298 | } |
| 299 | |
| 300 | /* Translates an NP index into a PPP protocol number */ |
| 301 | static const int npindex_to_proto[NUM_NP] = { |
| 302 | PPP_IP, |
| 303 | PPP_IPV6, |
| 304 | PPP_IPX, |
| 305 | PPP_AT, |
| 306 | PPP_MPLS_UC, |
| 307 | PPP_MPLS_MC, |
| 308 | }; |
| 309 | |
| 310 | /* Translates an ethertype into an NP index */ |
| 311 | static inline int ethertype_to_npindex(int ethertype) |
| 312 | { |
| 313 | switch (ethertype) { |
| 314 | case ETH_P_IP: |
| 315 | return NP_IP; |
| 316 | case ETH_P_IPV6: |
| 317 | return NP_IPV6; |
| 318 | case ETH_P_IPX: |
| 319 | return NP_IPX; |
| 320 | case ETH_P_PPPTALK: |
| 321 | case ETH_P_ATALK: |
| 322 | return NP_AT; |
| 323 | case ETH_P_MPLS_UC: |
| 324 | return NP_MPLS_UC; |
| 325 | case ETH_P_MPLS_MC: |
| 326 | return NP_MPLS_MC; |
| 327 | } |
| 328 | return -1; |
| 329 | } |
| 330 | |
| 331 | /* Translates an NP index into an ethertype */ |
| 332 | static const int npindex_to_ethertype[NUM_NP] = { |
| 333 | ETH_P_IP, |
| 334 | ETH_P_IPV6, |
| 335 | ETH_P_IPX, |
| 336 | ETH_P_PPPTALK, |
| 337 | ETH_P_MPLS_UC, |
| 338 | ETH_P_MPLS_MC, |
| 339 | }; |
| 340 | |
| 341 | /* |
| 342 | * Locking shorthand. |
| 343 | */ |
| 344 | #define ppp_xmit_lock(ppp) spin_lock_bh(&(ppp)->wlock) |
| 345 | #define ppp_xmit_unlock(ppp) spin_unlock_bh(&(ppp)->wlock) |
| 346 | #define ppp_recv_lock(ppp) spin_lock_bh(&(ppp)->rlock) |
| 347 | #define ppp_recv_unlock(ppp) spin_unlock_bh(&(ppp)->rlock) |
| 348 | #define ppp_lock(ppp) do { ppp_xmit_lock(ppp); \ |
| 349 | ppp_recv_lock(ppp); } while (0) |
| 350 | #define ppp_unlock(ppp) do { ppp_recv_unlock(ppp); \ |
| 351 | ppp_xmit_unlock(ppp); } while (0) |
| 352 | |
| 353 | /* |
| 354 | * /dev/ppp device routines. |
| 355 | * The /dev/ppp device is used by pppd to control the ppp unit. |
| 356 | * It supports the read, write, ioctl and poll functions. |
| 357 | * Open instances of /dev/ppp can be in one of three states: |
| 358 | * unattached, attached to a ppp unit, or attached to a ppp channel. |
| 359 | */ |
| 360 | static int ppp_open(struct inode *inode, struct file *file) |
| 361 | { |
| 362 | /* |
| 363 | * This could (should?) be enforced by the permissions on /dev/ppp. |
| 364 | */ |
| 365 | if (!capable(CAP_NET_ADMIN)) |
| 366 | return -EPERM; |
| 367 | return 0; |
| 368 | } |
| 369 | |
| 370 | static int ppp_release(struct inode *inode, struct file *file) |
| 371 | { |
| 372 | struct ppp_file *pf = file->private_data; |
| 373 | struct ppp *ppp; |
| 374 | |
| 375 | if (pf != 0) { |
| 376 | file->private_data = NULL; |
| 377 | if (pf->kind == INTERFACE) { |
| 378 | ppp = PF_TO_PPP(pf); |
| 379 | if (file == ppp->owner) |
| 380 | ppp_shutdown_interface(ppp); |
| 381 | } |
| 382 | if (atomic_dec_and_test(&pf->refcnt)) { |
| 383 | switch (pf->kind) { |
| 384 | case INTERFACE: |
| 385 | ppp_destroy_interface(PF_TO_PPP(pf)); |
| 386 | break; |
| 387 | case CHANNEL: |
| 388 | ppp_destroy_channel(PF_TO_CHANNEL(pf)); |
| 389 | break; |
| 390 | } |
| 391 | } |
| 392 | } |
| 393 | return 0; |
| 394 | } |
| 395 | |
| 396 | static ssize_t ppp_read(struct file *file, char __user *buf, |
| 397 | size_t count, loff_t *ppos) |
| 398 | { |
| 399 | struct ppp_file *pf = file->private_data; |
| 400 | DECLARE_WAITQUEUE(wait, current); |
| 401 | ssize_t ret; |
| 402 | struct sk_buff *skb = NULL; |
| 403 | |
| 404 | ret = count; |
| 405 | |
| 406 | if (pf == 0) |
| 407 | return -ENXIO; |
| 408 | add_wait_queue(&pf->rwait, &wait); |
| 409 | for (;;) { |
| 410 | set_current_state(TASK_INTERRUPTIBLE); |
| 411 | skb = skb_dequeue(&pf->rq); |
| 412 | if (skb) |
| 413 | break; |
| 414 | ret = 0; |
| 415 | if (pf->dead) |
| 416 | break; |
| 417 | if (pf->kind == INTERFACE) { |
| 418 | /* |
| 419 | * Return 0 (EOF) on an interface that has no |
| 420 | * channels connected, unless it is looping |
| 421 | * network traffic (demand mode). |
| 422 | */ |
| 423 | struct ppp *ppp = PF_TO_PPP(pf); |
| 424 | if (ppp->n_channels == 0 |
| 425 | && (ppp->flags & SC_LOOP_TRAFFIC) == 0) |
| 426 | break; |
| 427 | } |
| 428 | ret = -EAGAIN; |
| 429 | if (file->f_flags & O_NONBLOCK) |
| 430 | break; |
| 431 | ret = -ERESTARTSYS; |
| 432 | if (signal_pending(current)) |
| 433 | break; |
| 434 | schedule(); |
| 435 | } |
| 436 | set_current_state(TASK_RUNNING); |
| 437 | remove_wait_queue(&pf->rwait, &wait); |
| 438 | |
| 439 | if (skb == 0) |
| 440 | goto out; |
| 441 | |
| 442 | ret = -EOVERFLOW; |
| 443 | if (skb->len > count) |
| 444 | goto outf; |
| 445 | ret = -EFAULT; |
| 446 | if (copy_to_user(buf, skb->data, skb->len)) |
| 447 | goto outf; |
| 448 | ret = skb->len; |
| 449 | |
| 450 | outf: |
| 451 | kfree_skb(skb); |
| 452 | out: |
| 453 | return ret; |
| 454 | } |
| 455 | |
| 456 | static ssize_t ppp_write(struct file *file, const char __user *buf, |
| 457 | size_t count, loff_t *ppos) |
| 458 | { |
| 459 | struct ppp_file *pf = file->private_data; |
| 460 | struct sk_buff *skb; |
| 461 | ssize_t ret; |
| 462 | |
| 463 | if (pf == 0) |
| 464 | return -ENXIO; |
| 465 | ret = -ENOMEM; |
| 466 | skb = alloc_skb(count + pf->hdrlen, GFP_KERNEL); |
| 467 | if (skb == 0) |
| 468 | goto out; |
| 469 | skb_reserve(skb, pf->hdrlen); |
| 470 | ret = -EFAULT; |
| 471 | if (copy_from_user(skb_put(skb, count), buf, count)) { |
| 472 | kfree_skb(skb); |
| 473 | goto out; |
| 474 | } |
| 475 | |
| 476 | skb_queue_tail(&pf->xq, skb); |
| 477 | |
| 478 | switch (pf->kind) { |
| 479 | case INTERFACE: |
| 480 | ppp_xmit_process(PF_TO_PPP(pf)); |
| 481 | break; |
| 482 | case CHANNEL: |
| 483 | ppp_channel_push(PF_TO_CHANNEL(pf)); |
| 484 | break; |
| 485 | } |
| 486 | |
| 487 | ret = count; |
| 488 | |
| 489 | out: |
| 490 | return ret; |
| 491 | } |
| 492 | |
| 493 | /* No kernel lock - fine */ |
| 494 | static unsigned int ppp_poll(struct file *file, poll_table *wait) |
| 495 | { |
| 496 | struct ppp_file *pf = file->private_data; |
| 497 | unsigned int mask; |
| 498 | |
| 499 | if (pf == 0) |
| 500 | return 0; |
| 501 | poll_wait(file, &pf->rwait, wait); |
| 502 | mask = POLLOUT | POLLWRNORM; |
| 503 | if (skb_peek(&pf->rq) != 0) |
| 504 | mask |= POLLIN | POLLRDNORM; |
| 505 | if (pf->dead) |
| 506 | mask |= POLLHUP; |
| 507 | else if (pf->kind == INTERFACE) { |
| 508 | /* see comment in ppp_read */ |
| 509 | struct ppp *ppp = PF_TO_PPP(pf); |
| 510 | if (ppp->n_channels == 0 |
| 511 | && (ppp->flags & SC_LOOP_TRAFFIC) == 0) |
| 512 | mask |= POLLIN | POLLRDNORM; |
| 513 | } |
| 514 | |
| 515 | return mask; |
| 516 | } |
| 517 | |
| 518 | #ifdef CONFIG_PPP_FILTER |
| 519 | static int get_filter(void __user *arg, struct sock_filter **p) |
| 520 | { |
| 521 | struct sock_fprog uprog; |
| 522 | struct sock_filter *code = NULL; |
| 523 | int len, err; |
| 524 | |
| 525 | if (copy_from_user(&uprog, arg, sizeof(uprog))) |
| 526 | return -EFAULT; |
| 527 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 528 | if (!uprog.len) { |
| 529 | *p = NULL; |
| 530 | return 0; |
| 531 | } |
| 532 | |
| 533 | len = uprog.len * sizeof(struct sock_filter); |
| 534 | code = kmalloc(len, GFP_KERNEL); |
| 535 | if (code == NULL) |
| 536 | return -ENOMEM; |
| 537 | |
| 538 | if (copy_from_user(code, uprog.filter, len)) { |
| 539 | kfree(code); |
| 540 | return -EFAULT; |
| 541 | } |
| 542 | |
| 543 | err = sk_chk_filter(code, uprog.len); |
| 544 | if (err) { |
| 545 | kfree(code); |
| 546 | return err; |
| 547 | } |
| 548 | |
| 549 | *p = code; |
| 550 | return uprog.len; |
| 551 | } |
| 552 | #endif /* CONFIG_PPP_FILTER */ |
| 553 | |
| 554 | static int ppp_ioctl(struct inode *inode, struct file *file, |
| 555 | unsigned int cmd, unsigned long arg) |
| 556 | { |
| 557 | struct ppp_file *pf = file->private_data; |
| 558 | struct ppp *ppp; |
| 559 | int err = -EFAULT, val, val2, i; |
| 560 | struct ppp_idle idle; |
| 561 | struct npioctl npi; |
| 562 | int unit, cflags; |
| 563 | struct slcompress *vj; |
| 564 | void __user *argp = (void __user *)arg; |
| 565 | int __user *p = argp; |
| 566 | |
| 567 | if (pf == 0) |
| 568 | return ppp_unattached_ioctl(pf, file, cmd, arg); |
| 569 | |
| 570 | if (cmd == PPPIOCDETACH) { |
| 571 | /* |
| 572 | * We have to be careful here... if the file descriptor |
| 573 | * has been dup'd, we could have another process in the |
| 574 | * middle of a poll using the same file *, so we had |
| 575 | * better not free the interface data structures - |
| 576 | * instead we fail the ioctl. Even in this case, we |
| 577 | * shut down the interface if we are the owner of it. |
| 578 | * Actually, we should get rid of PPPIOCDETACH, userland |
| 579 | * (i.e. pppd) could achieve the same effect by closing |
| 580 | * this fd and reopening /dev/ppp. |
| 581 | */ |
| 582 | err = -EINVAL; |
| 583 | if (pf->kind == INTERFACE) { |
| 584 | ppp = PF_TO_PPP(pf); |
| 585 | if (file == ppp->owner) |
| 586 | ppp_shutdown_interface(ppp); |
| 587 | } |
| 588 | if (atomic_read(&file->f_count) <= 2) { |
| 589 | ppp_release(inode, file); |
| 590 | err = 0; |
| 591 | } else |
| 592 | printk(KERN_DEBUG "PPPIOCDETACH file->f_count=%d\n", |
| 593 | atomic_read(&file->f_count)); |
| 594 | return err; |
| 595 | } |
| 596 | |
| 597 | if (pf->kind == CHANNEL) { |
| 598 | struct channel *pch = PF_TO_CHANNEL(pf); |
| 599 | struct ppp_channel *chan; |
| 600 | |
| 601 | switch (cmd) { |
| 602 | case PPPIOCCONNECT: |
| 603 | if (get_user(unit, p)) |
| 604 | break; |
| 605 | err = ppp_connect_channel(pch, unit); |
| 606 | break; |
| 607 | |
| 608 | case PPPIOCDISCONN: |
| 609 | err = ppp_disconnect_channel(pch); |
| 610 | break; |
| 611 | |
| 612 | default: |
| 613 | down_read(&pch->chan_sem); |
| 614 | chan = pch->chan; |
| 615 | err = -ENOTTY; |
| 616 | if (chan && chan->ops->ioctl) |
| 617 | err = chan->ops->ioctl(chan, cmd, arg); |
| 618 | up_read(&pch->chan_sem); |
| 619 | } |
| 620 | return err; |
| 621 | } |
| 622 | |
| 623 | if (pf->kind != INTERFACE) { |
| 624 | /* can't happen */ |
| 625 | printk(KERN_ERR "PPP: not interface or channel??\n"); |
| 626 | return -EINVAL; |
| 627 | } |
| 628 | |
| 629 | ppp = PF_TO_PPP(pf); |
| 630 | switch (cmd) { |
| 631 | case PPPIOCSMRU: |
| 632 | if (get_user(val, p)) |
| 633 | break; |
| 634 | ppp->mru = val; |
| 635 | err = 0; |
| 636 | break; |
| 637 | |
| 638 | case PPPIOCSFLAGS: |
| 639 | if (get_user(val, p)) |
| 640 | break; |
| 641 | ppp_lock(ppp); |
| 642 | cflags = ppp->flags & ~val; |
| 643 | ppp->flags = val & SC_FLAG_BITS; |
| 644 | ppp_unlock(ppp); |
| 645 | if (cflags & SC_CCP_OPEN) |
| 646 | ppp_ccp_closed(ppp); |
| 647 | err = 0; |
| 648 | break; |
| 649 | |
| 650 | case PPPIOCGFLAGS: |
| 651 | val = ppp->flags | ppp->xstate | ppp->rstate; |
| 652 | if (put_user(val, p)) |
| 653 | break; |
| 654 | err = 0; |
| 655 | break; |
| 656 | |
| 657 | case PPPIOCSCOMPRESS: |
| 658 | err = ppp_set_compress(ppp, arg); |
| 659 | break; |
| 660 | |
| 661 | case PPPIOCGUNIT: |
| 662 | if (put_user(ppp->file.index, p)) |
| 663 | break; |
| 664 | err = 0; |
| 665 | break; |
| 666 | |
| 667 | case PPPIOCSDEBUG: |
| 668 | if (get_user(val, p)) |
| 669 | break; |
| 670 | ppp->debug = val; |
| 671 | err = 0; |
| 672 | break; |
| 673 | |
| 674 | case PPPIOCGDEBUG: |
| 675 | if (put_user(ppp->debug, p)) |
| 676 | break; |
| 677 | err = 0; |
| 678 | break; |
| 679 | |
| 680 | case PPPIOCGIDLE: |
| 681 | idle.xmit_idle = (jiffies - ppp->last_xmit) / HZ; |
| 682 | idle.recv_idle = (jiffies - ppp->last_recv) / HZ; |
| 683 | if (copy_to_user(argp, &idle, sizeof(idle))) |
| 684 | break; |
| 685 | err = 0; |
| 686 | break; |
| 687 | |
| 688 | case PPPIOCSMAXCID: |
| 689 | if (get_user(val, p)) |
| 690 | break; |
| 691 | val2 = 15; |
| 692 | if ((val >> 16) != 0) { |
| 693 | val2 = val >> 16; |
| 694 | val &= 0xffff; |
| 695 | } |
| 696 | vj = slhc_init(val2+1, val+1); |
| 697 | if (vj == 0) { |
| 698 | printk(KERN_ERR "PPP: no memory (VJ compressor)\n"); |
| 699 | err = -ENOMEM; |
| 700 | break; |
| 701 | } |
| 702 | ppp_lock(ppp); |
| 703 | if (ppp->vj != 0) |
| 704 | slhc_free(ppp->vj); |
| 705 | ppp->vj = vj; |
| 706 | ppp_unlock(ppp); |
| 707 | err = 0; |
| 708 | break; |
| 709 | |
| 710 | case PPPIOCGNPMODE: |
| 711 | case PPPIOCSNPMODE: |
| 712 | if (copy_from_user(&npi, argp, sizeof(npi))) |
| 713 | break; |
| 714 | err = proto_to_npindex(npi.protocol); |
| 715 | if (err < 0) |
| 716 | break; |
| 717 | i = err; |
| 718 | if (cmd == PPPIOCGNPMODE) { |
| 719 | err = -EFAULT; |
| 720 | npi.mode = ppp->npmode[i]; |
| 721 | if (copy_to_user(argp, &npi, sizeof(npi))) |
| 722 | break; |
| 723 | } else { |
| 724 | ppp->npmode[i] = npi.mode; |
| 725 | /* we may be able to transmit more packets now (??) */ |
| 726 | netif_wake_queue(ppp->dev); |
| 727 | } |
| 728 | err = 0; |
| 729 | break; |
| 730 | |
| 731 | #ifdef CONFIG_PPP_FILTER |
| 732 | case PPPIOCSPASS: |
| 733 | { |
| 734 | struct sock_filter *code; |
| 735 | err = get_filter(argp, &code); |
| 736 | if (err >= 0) { |
| 737 | ppp_lock(ppp); |
| 738 | kfree(ppp->pass_filter); |
| 739 | ppp->pass_filter = code; |
| 740 | ppp->pass_len = err; |
| 741 | ppp_unlock(ppp); |
| 742 | err = 0; |
| 743 | } |
| 744 | break; |
| 745 | } |
| 746 | case PPPIOCSACTIVE: |
| 747 | { |
| 748 | struct sock_filter *code; |
| 749 | err = get_filter(argp, &code); |
| 750 | if (err >= 0) { |
| 751 | ppp_lock(ppp); |
| 752 | kfree(ppp->active_filter); |
| 753 | ppp->active_filter = code; |
| 754 | ppp->active_len = err; |
| 755 | ppp_unlock(ppp); |
| 756 | err = 0; |
| 757 | } |
| 758 | break; |
| 759 | } |
| 760 | #endif /* CONFIG_PPP_FILTER */ |
| 761 | |
| 762 | #ifdef CONFIG_PPP_MULTILINK |
| 763 | case PPPIOCSMRRU: |
| 764 | if (get_user(val, p)) |
| 765 | break; |
| 766 | ppp_recv_lock(ppp); |
| 767 | ppp->mrru = val; |
| 768 | ppp_recv_unlock(ppp); |
| 769 | err = 0; |
| 770 | break; |
| 771 | #endif /* CONFIG_PPP_MULTILINK */ |
| 772 | |
| 773 | default: |
| 774 | err = -ENOTTY; |
| 775 | } |
| 776 | |
| 777 | return err; |
| 778 | } |
| 779 | |
| 780 | static int ppp_unattached_ioctl(struct ppp_file *pf, struct file *file, |
| 781 | unsigned int cmd, unsigned long arg) |
| 782 | { |
| 783 | int unit, err = -EFAULT; |
| 784 | struct ppp *ppp; |
| 785 | struct channel *chan; |
| 786 | int __user *p = (int __user *)arg; |
| 787 | |
| 788 | switch (cmd) { |
| 789 | case PPPIOCNEWUNIT: |
| 790 | /* Create a new ppp unit */ |
| 791 | if (get_user(unit, p)) |
| 792 | break; |
| 793 | ppp = ppp_create_interface(unit, &err); |
| 794 | if (ppp == 0) |
| 795 | break; |
| 796 | file->private_data = &ppp->file; |
| 797 | ppp->owner = file; |
| 798 | err = -EFAULT; |
| 799 | if (put_user(ppp->file.index, p)) |
| 800 | break; |
| 801 | err = 0; |
| 802 | break; |
| 803 | |
| 804 | case PPPIOCATTACH: |
| 805 | /* Attach to an existing ppp unit */ |
| 806 | if (get_user(unit, p)) |
| 807 | break; |
Arjan van de Ven | 8ed965d | 2006-03-23 03:00:21 -0800 | [diff] [blame] | 808 | mutex_lock(&all_ppp_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 809 | err = -ENXIO; |
| 810 | ppp = ppp_find_unit(unit); |
| 811 | if (ppp != 0) { |
| 812 | atomic_inc(&ppp->file.refcnt); |
| 813 | file->private_data = &ppp->file; |
| 814 | err = 0; |
| 815 | } |
Arjan van de Ven | 8ed965d | 2006-03-23 03:00:21 -0800 | [diff] [blame] | 816 | mutex_unlock(&all_ppp_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 817 | break; |
| 818 | |
| 819 | case PPPIOCATTCHAN: |
| 820 | if (get_user(unit, p)) |
| 821 | break; |
| 822 | spin_lock_bh(&all_channels_lock); |
| 823 | err = -ENXIO; |
| 824 | chan = ppp_find_channel(unit); |
| 825 | if (chan != 0) { |
| 826 | atomic_inc(&chan->file.refcnt); |
| 827 | file->private_data = &chan->file; |
| 828 | err = 0; |
| 829 | } |
| 830 | spin_unlock_bh(&all_channels_lock); |
| 831 | break; |
| 832 | |
| 833 | default: |
| 834 | err = -ENOTTY; |
| 835 | } |
| 836 | return err; |
| 837 | } |
| 838 | |
| 839 | static struct file_operations ppp_device_fops = { |
| 840 | .owner = THIS_MODULE, |
| 841 | .read = ppp_read, |
| 842 | .write = ppp_write, |
| 843 | .poll = ppp_poll, |
| 844 | .ioctl = ppp_ioctl, |
| 845 | .open = ppp_open, |
| 846 | .release = ppp_release |
| 847 | }; |
| 848 | |
| 849 | #define PPP_MAJOR 108 |
| 850 | |
| 851 | /* Called at boot time if ppp is compiled into the kernel, |
| 852 | or at module load time (from init_module) if compiled as a module. */ |
| 853 | static int __init ppp_init(void) |
| 854 | { |
| 855 | int err; |
| 856 | |
| 857 | printk(KERN_INFO "PPP generic driver version " PPP_VERSION "\n"); |
| 858 | err = register_chrdev(PPP_MAJOR, "ppp", &ppp_device_fops); |
| 859 | if (!err) { |
gregkh@suse.de | 56b2293 | 2005-03-23 10:01:41 -0800 | [diff] [blame] | 860 | ppp_class = class_create(THIS_MODULE, "ppp"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 861 | if (IS_ERR(ppp_class)) { |
| 862 | err = PTR_ERR(ppp_class); |
| 863 | goto out_chrdev; |
| 864 | } |
Greg Kroah-Hartman | 53f4654 | 2005-10-27 22:25:43 -0700 | [diff] [blame] | 865 | class_device_create(ppp_class, NULL, MKDEV(PPP_MAJOR, 0), NULL, "ppp"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 866 | err = devfs_mk_cdev(MKDEV(PPP_MAJOR, 0), |
| 867 | S_IFCHR|S_IRUSR|S_IWUSR, "ppp"); |
| 868 | if (err) |
| 869 | goto out_class; |
| 870 | } |
| 871 | |
| 872 | out: |
| 873 | if (err) |
| 874 | printk(KERN_ERR "failed to register PPP device (%d)\n", err); |
| 875 | return err; |
| 876 | |
| 877 | out_class: |
gregkh@suse.de | 56b2293 | 2005-03-23 10:01:41 -0800 | [diff] [blame] | 878 | class_device_destroy(ppp_class, MKDEV(PPP_MAJOR,0)); |
| 879 | class_destroy(ppp_class); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 880 | out_chrdev: |
| 881 | unregister_chrdev(PPP_MAJOR, "ppp"); |
| 882 | goto out; |
| 883 | } |
| 884 | |
| 885 | /* |
| 886 | * Network interface unit routines. |
| 887 | */ |
| 888 | static int |
| 889 | ppp_start_xmit(struct sk_buff *skb, struct net_device *dev) |
| 890 | { |
| 891 | struct ppp *ppp = (struct ppp *) dev->priv; |
| 892 | int npi, proto; |
| 893 | unsigned char *pp; |
| 894 | |
| 895 | npi = ethertype_to_npindex(ntohs(skb->protocol)); |
| 896 | if (npi < 0) |
| 897 | goto outf; |
| 898 | |
| 899 | /* Drop, accept or reject the packet */ |
| 900 | switch (ppp->npmode[npi]) { |
| 901 | case NPMODE_PASS: |
| 902 | break; |
| 903 | case NPMODE_QUEUE: |
| 904 | /* it would be nice to have a way to tell the network |
| 905 | system to queue this one up for later. */ |
| 906 | goto outf; |
| 907 | case NPMODE_DROP: |
| 908 | case NPMODE_ERROR: |
| 909 | goto outf; |
| 910 | } |
| 911 | |
| 912 | /* Put the 2-byte PPP protocol number on the front, |
| 913 | making sure there is room for the address and control fields. */ |
| 914 | if (skb_headroom(skb) < PPP_HDRLEN) { |
| 915 | struct sk_buff *ns; |
| 916 | |
| 917 | ns = alloc_skb(skb->len + dev->hard_header_len, GFP_ATOMIC); |
| 918 | if (ns == 0) |
| 919 | goto outf; |
| 920 | skb_reserve(ns, dev->hard_header_len); |
| 921 | skb_copy_bits(skb, 0, skb_put(ns, skb->len), skb->len); |
| 922 | kfree_skb(skb); |
| 923 | skb = ns; |
| 924 | } |
| 925 | pp = skb_push(skb, 2); |
| 926 | proto = npindex_to_proto[npi]; |
| 927 | pp[0] = proto >> 8; |
| 928 | pp[1] = proto; |
| 929 | |
| 930 | netif_stop_queue(dev); |
| 931 | skb_queue_tail(&ppp->file.xq, skb); |
| 932 | ppp_xmit_process(ppp); |
| 933 | return 0; |
| 934 | |
| 935 | outf: |
| 936 | kfree_skb(skb); |
| 937 | ++ppp->stats.tx_dropped; |
| 938 | return 0; |
| 939 | } |
| 940 | |
| 941 | static struct net_device_stats * |
| 942 | ppp_net_stats(struct net_device *dev) |
| 943 | { |
| 944 | struct ppp *ppp = (struct ppp *) dev->priv; |
| 945 | |
| 946 | return &ppp->stats; |
| 947 | } |
| 948 | |
| 949 | static int |
| 950 | ppp_net_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) |
| 951 | { |
| 952 | struct ppp *ppp = dev->priv; |
| 953 | int err = -EFAULT; |
| 954 | void __user *addr = (void __user *) ifr->ifr_ifru.ifru_data; |
| 955 | struct ppp_stats stats; |
| 956 | struct ppp_comp_stats cstats; |
| 957 | char *vers; |
| 958 | |
| 959 | switch (cmd) { |
| 960 | case SIOCGPPPSTATS: |
| 961 | ppp_get_stats(ppp, &stats); |
| 962 | if (copy_to_user(addr, &stats, sizeof(stats))) |
| 963 | break; |
| 964 | err = 0; |
| 965 | break; |
| 966 | |
| 967 | case SIOCGPPPCSTATS: |
| 968 | memset(&cstats, 0, sizeof(cstats)); |
| 969 | if (ppp->xc_state != 0) |
| 970 | ppp->xcomp->comp_stat(ppp->xc_state, &cstats.c); |
| 971 | if (ppp->rc_state != 0) |
| 972 | ppp->rcomp->decomp_stat(ppp->rc_state, &cstats.d); |
| 973 | if (copy_to_user(addr, &cstats, sizeof(cstats))) |
| 974 | break; |
| 975 | err = 0; |
| 976 | break; |
| 977 | |
| 978 | case SIOCGPPPVER: |
| 979 | vers = PPP_VERSION; |
| 980 | if (copy_to_user(addr, vers, strlen(vers) + 1)) |
| 981 | break; |
| 982 | err = 0; |
| 983 | break; |
| 984 | |
| 985 | default: |
| 986 | err = -EINVAL; |
| 987 | } |
| 988 | |
| 989 | return err; |
| 990 | } |
| 991 | |
| 992 | static void ppp_setup(struct net_device *dev) |
| 993 | { |
| 994 | dev->hard_header_len = PPP_HDRLEN; |
| 995 | dev->mtu = PPP_MTU; |
| 996 | dev->addr_len = 0; |
| 997 | dev->tx_queue_len = 3; |
| 998 | dev->type = ARPHRD_PPP; |
| 999 | dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST; |
| 1000 | } |
| 1001 | |
| 1002 | /* |
| 1003 | * Transmit-side routines. |
| 1004 | */ |
| 1005 | |
| 1006 | /* |
| 1007 | * Called to do any work queued up on the transmit side |
| 1008 | * that can now be done. |
| 1009 | */ |
| 1010 | static void |
| 1011 | ppp_xmit_process(struct ppp *ppp) |
| 1012 | { |
| 1013 | struct sk_buff *skb; |
| 1014 | |
| 1015 | ppp_xmit_lock(ppp); |
| 1016 | if (ppp->dev != 0) { |
| 1017 | ppp_push(ppp); |
| 1018 | while (ppp->xmit_pending == 0 |
| 1019 | && (skb = skb_dequeue(&ppp->file.xq)) != 0) |
| 1020 | ppp_send_frame(ppp, skb); |
| 1021 | /* If there's no work left to do, tell the core net |
| 1022 | code that we can accept some more. */ |
| 1023 | if (ppp->xmit_pending == 0 && skb_peek(&ppp->file.xq) == 0) |
| 1024 | netif_wake_queue(ppp->dev); |
| 1025 | } |
| 1026 | ppp_xmit_unlock(ppp); |
| 1027 | } |
| 1028 | |
Matt Domsch | b3f9b92 | 2005-11-08 09:40:47 -0800 | [diff] [blame] | 1029 | static inline struct sk_buff * |
| 1030 | pad_compress_skb(struct ppp *ppp, struct sk_buff *skb) |
| 1031 | { |
| 1032 | struct sk_buff *new_skb; |
| 1033 | int len; |
| 1034 | int new_skb_size = ppp->dev->mtu + |
| 1035 | ppp->xcomp->comp_extra + ppp->dev->hard_header_len; |
| 1036 | int compressor_skb_size = ppp->dev->mtu + |
| 1037 | ppp->xcomp->comp_extra + PPP_HDRLEN; |
| 1038 | new_skb = alloc_skb(new_skb_size, GFP_ATOMIC); |
| 1039 | if (!new_skb) { |
| 1040 | if (net_ratelimit()) |
| 1041 | printk(KERN_ERR "PPP: no memory (comp pkt)\n"); |
| 1042 | return NULL; |
| 1043 | } |
| 1044 | if (ppp->dev->hard_header_len > PPP_HDRLEN) |
| 1045 | skb_reserve(new_skb, |
| 1046 | ppp->dev->hard_header_len - PPP_HDRLEN); |
| 1047 | |
| 1048 | /* compressor still expects A/C bytes in hdr */ |
| 1049 | len = ppp->xcomp->compress(ppp->xc_state, skb->data - 2, |
| 1050 | new_skb->data, skb->len + 2, |
| 1051 | compressor_skb_size); |
| 1052 | if (len > 0 && (ppp->flags & SC_CCP_UP)) { |
| 1053 | kfree_skb(skb); |
| 1054 | skb = new_skb; |
| 1055 | skb_put(skb, len); |
| 1056 | skb_pull(skb, 2); /* pull off A/C bytes */ |
| 1057 | } else if (len == 0) { |
| 1058 | /* didn't compress, or CCP not up yet */ |
| 1059 | kfree_skb(new_skb); |
| 1060 | new_skb = skb; |
| 1061 | } else { |
| 1062 | /* |
| 1063 | * (len < 0) |
| 1064 | * MPPE requires that we do not send unencrypted |
| 1065 | * frames. The compressor will return -1 if we |
| 1066 | * should drop the frame. We cannot simply test |
| 1067 | * the compress_proto because MPPE and MPPC share |
| 1068 | * the same number. |
| 1069 | */ |
| 1070 | if (net_ratelimit()) |
| 1071 | printk(KERN_ERR "ppp: compressor dropped pkt\n"); |
| 1072 | kfree_skb(skb); |
| 1073 | kfree_skb(new_skb); |
| 1074 | new_skb = NULL; |
| 1075 | } |
| 1076 | return new_skb; |
| 1077 | } |
| 1078 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1079 | /* |
| 1080 | * Compress and send a frame. |
| 1081 | * The caller should have locked the xmit path, |
| 1082 | * and xmit_pending should be 0. |
| 1083 | */ |
| 1084 | static void |
| 1085 | ppp_send_frame(struct ppp *ppp, struct sk_buff *skb) |
| 1086 | { |
| 1087 | int proto = PPP_PROTO(skb); |
| 1088 | struct sk_buff *new_skb; |
| 1089 | int len; |
| 1090 | unsigned char *cp; |
| 1091 | |
| 1092 | if (proto < 0x8000) { |
| 1093 | #ifdef CONFIG_PPP_FILTER |
| 1094 | /* check if we should pass this packet */ |
| 1095 | /* the filter instructions are constructed assuming |
| 1096 | a four-byte PPP header on each packet */ |
| 1097 | *skb_push(skb, 2) = 1; |
| 1098 | if (ppp->pass_filter |
| 1099 | && sk_run_filter(skb, ppp->pass_filter, |
| 1100 | ppp->pass_len) == 0) { |
| 1101 | if (ppp->debug & 1) |
| 1102 | printk(KERN_DEBUG "PPP: outbound frame not passed\n"); |
| 1103 | kfree_skb(skb); |
| 1104 | return; |
| 1105 | } |
| 1106 | /* if this packet passes the active filter, record the time */ |
| 1107 | if (!(ppp->active_filter |
| 1108 | && sk_run_filter(skb, ppp->active_filter, |
| 1109 | ppp->active_len) == 0)) |
| 1110 | ppp->last_xmit = jiffies; |
| 1111 | skb_pull(skb, 2); |
| 1112 | #else |
| 1113 | /* for data packets, record the time */ |
| 1114 | ppp->last_xmit = jiffies; |
| 1115 | #endif /* CONFIG_PPP_FILTER */ |
| 1116 | } |
| 1117 | |
| 1118 | ++ppp->stats.tx_packets; |
| 1119 | ppp->stats.tx_bytes += skb->len - 2; |
| 1120 | |
| 1121 | switch (proto) { |
| 1122 | case PPP_IP: |
| 1123 | if (ppp->vj == 0 || (ppp->flags & SC_COMP_TCP) == 0) |
| 1124 | break; |
| 1125 | /* try to do VJ TCP header compression */ |
| 1126 | new_skb = alloc_skb(skb->len + ppp->dev->hard_header_len - 2, |
| 1127 | GFP_ATOMIC); |
| 1128 | if (new_skb == 0) { |
| 1129 | printk(KERN_ERR "PPP: no memory (VJ comp pkt)\n"); |
| 1130 | goto drop; |
| 1131 | } |
| 1132 | skb_reserve(new_skb, ppp->dev->hard_header_len - 2); |
| 1133 | cp = skb->data + 2; |
| 1134 | len = slhc_compress(ppp->vj, cp, skb->len - 2, |
| 1135 | new_skb->data + 2, &cp, |
| 1136 | !(ppp->flags & SC_NO_TCP_CCID)); |
| 1137 | if (cp == skb->data + 2) { |
| 1138 | /* didn't compress */ |
| 1139 | kfree_skb(new_skb); |
| 1140 | } else { |
| 1141 | if (cp[0] & SL_TYPE_COMPRESSED_TCP) { |
| 1142 | proto = PPP_VJC_COMP; |
| 1143 | cp[0] &= ~SL_TYPE_COMPRESSED_TCP; |
| 1144 | } else { |
| 1145 | proto = PPP_VJC_UNCOMP; |
| 1146 | cp[0] = skb->data[2]; |
| 1147 | } |
| 1148 | kfree_skb(skb); |
| 1149 | skb = new_skb; |
| 1150 | cp = skb_put(skb, len + 2); |
| 1151 | cp[0] = 0; |
| 1152 | cp[1] = proto; |
| 1153 | } |
| 1154 | break; |
| 1155 | |
| 1156 | case PPP_CCP: |
| 1157 | /* peek at outbound CCP frames */ |
| 1158 | ppp_ccp_peek(ppp, skb, 0); |
| 1159 | break; |
| 1160 | } |
| 1161 | |
| 1162 | /* try to do packet compression */ |
| 1163 | if ((ppp->xstate & SC_COMP_RUN) && ppp->xc_state != 0 |
| 1164 | && proto != PPP_LCP && proto != PPP_CCP) { |
Matt Domsch | b3f9b92 | 2005-11-08 09:40:47 -0800 | [diff] [blame] | 1165 | if (!(ppp->flags & SC_CCP_UP) && (ppp->flags & SC_MUST_COMP)) { |
| 1166 | if (net_ratelimit()) |
| 1167 | printk(KERN_ERR "ppp: compression required but down - pkt dropped.\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1168 | goto drop; |
| 1169 | } |
Matt Domsch | b3f9b92 | 2005-11-08 09:40:47 -0800 | [diff] [blame] | 1170 | skb = pad_compress_skb(ppp, skb); |
| 1171 | if (!skb) |
| 1172 | goto drop; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1173 | } |
| 1174 | |
| 1175 | /* |
| 1176 | * If we are waiting for traffic (demand dialling), |
| 1177 | * queue it up for pppd to receive. |
| 1178 | */ |
| 1179 | if (ppp->flags & SC_LOOP_TRAFFIC) { |
| 1180 | if (ppp->file.rq.qlen > PPP_MAX_RQLEN) |
| 1181 | goto drop; |
| 1182 | skb_queue_tail(&ppp->file.rq, skb); |
| 1183 | wake_up_interruptible(&ppp->file.rwait); |
| 1184 | return; |
| 1185 | } |
| 1186 | |
| 1187 | ppp->xmit_pending = skb; |
| 1188 | ppp_push(ppp); |
| 1189 | return; |
| 1190 | |
| 1191 | drop: |
Matt Domsch | b3f9b92 | 2005-11-08 09:40:47 -0800 | [diff] [blame] | 1192 | if (skb) |
| 1193 | kfree_skb(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1194 | ++ppp->stats.tx_errors; |
| 1195 | } |
| 1196 | |
| 1197 | /* |
| 1198 | * Try to send the frame in xmit_pending. |
| 1199 | * The caller should have the xmit path locked. |
| 1200 | */ |
| 1201 | static void |
| 1202 | ppp_push(struct ppp *ppp) |
| 1203 | { |
| 1204 | struct list_head *list; |
| 1205 | struct channel *pch; |
| 1206 | struct sk_buff *skb = ppp->xmit_pending; |
| 1207 | |
| 1208 | if (skb == 0) |
| 1209 | return; |
| 1210 | |
| 1211 | list = &ppp->channels; |
| 1212 | if (list_empty(list)) { |
| 1213 | /* nowhere to send the packet, just drop it */ |
| 1214 | ppp->xmit_pending = NULL; |
| 1215 | kfree_skb(skb); |
| 1216 | return; |
| 1217 | } |
| 1218 | |
| 1219 | if ((ppp->flags & SC_MULTILINK) == 0) { |
| 1220 | /* not doing multilink: send it down the first channel */ |
| 1221 | list = list->next; |
| 1222 | pch = list_entry(list, struct channel, clist); |
| 1223 | |
| 1224 | spin_lock_bh(&pch->downl); |
| 1225 | if (pch->chan) { |
| 1226 | if (pch->chan->ops->start_xmit(pch->chan, skb)) |
| 1227 | ppp->xmit_pending = NULL; |
| 1228 | } else { |
| 1229 | /* channel got unregistered */ |
| 1230 | kfree_skb(skb); |
| 1231 | ppp->xmit_pending = NULL; |
| 1232 | } |
| 1233 | spin_unlock_bh(&pch->downl); |
| 1234 | return; |
| 1235 | } |
| 1236 | |
| 1237 | #ifdef CONFIG_PPP_MULTILINK |
| 1238 | /* Multilink: fragment the packet over as many links |
| 1239 | as can take the packet at the moment. */ |
| 1240 | if (!ppp_mp_explode(ppp, skb)) |
| 1241 | return; |
| 1242 | #endif /* CONFIG_PPP_MULTILINK */ |
| 1243 | |
| 1244 | ppp->xmit_pending = NULL; |
| 1245 | kfree_skb(skb); |
| 1246 | } |
| 1247 | |
| 1248 | #ifdef CONFIG_PPP_MULTILINK |
| 1249 | /* |
| 1250 | * Divide a packet to be transmitted into fragments and |
| 1251 | * send them out the individual links. |
| 1252 | */ |
| 1253 | static int ppp_mp_explode(struct ppp *ppp, struct sk_buff *skb) |
| 1254 | { |
Paul Mackerras | 516cd15 | 2005-05-12 19:47:12 -0400 | [diff] [blame] | 1255 | int len, fragsize; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1256 | int i, bits, hdrlen, mtu; |
Paul Mackerras | 516cd15 | 2005-05-12 19:47:12 -0400 | [diff] [blame] | 1257 | int flen; |
| 1258 | int navail, nfree; |
| 1259 | int nbigger; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1260 | unsigned char *p, *q; |
| 1261 | struct list_head *list; |
| 1262 | struct channel *pch; |
| 1263 | struct sk_buff *frag; |
| 1264 | struct ppp_channel *chan; |
| 1265 | |
Paul Mackerras | 516cd15 | 2005-05-12 19:47:12 -0400 | [diff] [blame] | 1266 | nfree = 0; /* # channels which have no packet already queued */ |
| 1267 | navail = 0; /* total # of usable channels (not deregistered) */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1268 | hdrlen = (ppp->flags & SC_MP_XSHORTSEQ)? MPHDRLEN_SSN: MPHDRLEN; |
Paul Mackerras | 516cd15 | 2005-05-12 19:47:12 -0400 | [diff] [blame] | 1269 | i = 0; |
Domen Puncer | 81616c5 | 2005-09-10 00:27:04 -0700 | [diff] [blame] | 1270 | list_for_each_entry(pch, &ppp->channels, clist) { |
Paul Mackerras | 516cd15 | 2005-05-12 19:47:12 -0400 | [diff] [blame] | 1271 | navail += pch->avail = (pch->chan != NULL); |
| 1272 | if (pch->avail) { |
David S. Miller | b03efcf | 2005-07-08 14:57:23 -0700 | [diff] [blame] | 1273 | if (skb_queue_empty(&pch->file.xq) || |
| 1274 | !pch->had_frag) { |
Paul Mackerras | 516cd15 | 2005-05-12 19:47:12 -0400 | [diff] [blame] | 1275 | pch->avail = 2; |
| 1276 | ++nfree; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1277 | } |
Paul Mackerras | 516cd15 | 2005-05-12 19:47:12 -0400 | [diff] [blame] | 1278 | if (!pch->had_frag && i < ppp->nxchan) |
| 1279 | ppp->nxchan = i; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1280 | } |
Paul Mackerras | 516cd15 | 2005-05-12 19:47:12 -0400 | [diff] [blame] | 1281 | ++i; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1282 | } |
Paul Mackerras | 516cd15 | 2005-05-12 19:47:12 -0400 | [diff] [blame] | 1283 | |
| 1284 | /* |
| 1285 | * Don't start sending this packet unless at least half of |
| 1286 | * the channels are free. This gives much better TCP |
| 1287 | * performance if we have a lot of channels. |
| 1288 | */ |
| 1289 | if (nfree == 0 || nfree < navail / 2) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1290 | return 0; /* can't take now, leave it in xmit_pending */ |
| 1291 | |
| 1292 | /* Do protocol field compression (XXX this should be optional) */ |
| 1293 | p = skb->data; |
| 1294 | len = skb->len; |
| 1295 | if (*p == 0) { |
| 1296 | ++p; |
| 1297 | --len; |
| 1298 | } |
| 1299 | |
Paul Mackerras | 516cd15 | 2005-05-12 19:47:12 -0400 | [diff] [blame] | 1300 | /* |
| 1301 | * Decide on fragment size. |
| 1302 | * We create a fragment for each free channel regardless of |
| 1303 | * how small they are (i.e. even 0 length) in order to minimize |
| 1304 | * the time that it will take to detect when a channel drops |
| 1305 | * a fragment. |
| 1306 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1307 | fragsize = len; |
Paul Mackerras | 516cd15 | 2005-05-12 19:47:12 -0400 | [diff] [blame] | 1308 | if (nfree > 1) |
| 1309 | fragsize = ROUNDUP(fragsize, nfree); |
| 1310 | /* nbigger channels get fragsize bytes, the rest get fragsize-1, |
| 1311 | except if nbigger==0, then they all get fragsize. */ |
| 1312 | nbigger = len % nfree; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1313 | |
| 1314 | /* skip to the channel after the one we last used |
| 1315 | and start at that one */ |
Domen Puncer | 81616c5 | 2005-09-10 00:27:04 -0700 | [diff] [blame] | 1316 | list = &ppp->channels; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1317 | for (i = 0; i < ppp->nxchan; ++i) { |
| 1318 | list = list->next; |
| 1319 | if (list == &ppp->channels) { |
| 1320 | i = 0; |
| 1321 | break; |
| 1322 | } |
| 1323 | } |
| 1324 | |
| 1325 | /* create a fragment for each channel */ |
| 1326 | bits = B; |
Paul Mackerras | 516cd15 | 2005-05-12 19:47:12 -0400 | [diff] [blame] | 1327 | while (nfree > 0 || len > 0) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1328 | list = list->next; |
| 1329 | if (list == &ppp->channels) { |
| 1330 | i = 0; |
| 1331 | continue; |
| 1332 | } |
| 1333 | pch = list_entry(list, struct channel, clist); |
| 1334 | ++i; |
| 1335 | if (!pch->avail) |
| 1336 | continue; |
| 1337 | |
Paul Mackerras | 516cd15 | 2005-05-12 19:47:12 -0400 | [diff] [blame] | 1338 | /* |
| 1339 | * Skip this channel if it has a fragment pending already and |
| 1340 | * we haven't given a fragment to all of the free channels. |
| 1341 | */ |
| 1342 | if (pch->avail == 1) { |
| 1343 | if (nfree > 0) |
| 1344 | continue; |
| 1345 | } else { |
| 1346 | --nfree; |
| 1347 | pch->avail = 1; |
| 1348 | } |
| 1349 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1350 | /* check the channel's mtu and whether it is still attached. */ |
| 1351 | spin_lock_bh(&pch->downl); |
Paul Mackerras | 516cd15 | 2005-05-12 19:47:12 -0400 | [diff] [blame] | 1352 | if (pch->chan == NULL) { |
| 1353 | /* can't use this channel, it's being deregistered */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1354 | spin_unlock_bh(&pch->downl); |
| 1355 | pch->avail = 0; |
Paul Mackerras | 516cd15 | 2005-05-12 19:47:12 -0400 | [diff] [blame] | 1356 | if (--navail == 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1357 | break; |
| 1358 | continue; |
| 1359 | } |
| 1360 | |
| 1361 | /* |
Paul Mackerras | 516cd15 | 2005-05-12 19:47:12 -0400 | [diff] [blame] | 1362 | * Create a fragment for this channel of |
| 1363 | * min(max(mtu+2-hdrlen, 4), fragsize, len) bytes. |
| 1364 | * If mtu+2-hdrlen < 4, that is a ridiculously small |
| 1365 | * MTU, so we use mtu = 2 + hdrlen. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1366 | */ |
| 1367 | if (fragsize > len) |
| 1368 | fragsize = len; |
Paul Mackerras | 516cd15 | 2005-05-12 19:47:12 -0400 | [diff] [blame] | 1369 | flen = fragsize; |
| 1370 | mtu = pch->chan->mtu + 2 - hdrlen; |
| 1371 | if (mtu < 4) |
| 1372 | mtu = 4; |
| 1373 | if (flen > mtu) |
| 1374 | flen = mtu; |
| 1375 | if (flen == len && nfree == 0) |
| 1376 | bits |= E; |
| 1377 | frag = alloc_skb(flen + hdrlen + (flen == 0), GFP_ATOMIC); |
| 1378 | if (frag == 0) |
| 1379 | goto noskb; |
| 1380 | q = skb_put(frag, flen + hdrlen); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1381 | |
Paul Mackerras | 516cd15 | 2005-05-12 19:47:12 -0400 | [diff] [blame] | 1382 | /* make the MP header */ |
| 1383 | q[0] = PPP_MP >> 8; |
| 1384 | q[1] = PPP_MP; |
| 1385 | if (ppp->flags & SC_MP_XSHORTSEQ) { |
| 1386 | q[2] = bits + ((ppp->nxseq >> 8) & 0xf); |
| 1387 | q[3] = ppp->nxseq; |
| 1388 | } else { |
| 1389 | q[2] = bits; |
| 1390 | q[3] = ppp->nxseq >> 16; |
| 1391 | q[4] = ppp->nxseq >> 8; |
| 1392 | q[5] = ppp->nxseq; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1393 | } |
Paul Mackerras | 516cd15 | 2005-05-12 19:47:12 -0400 | [diff] [blame] | 1394 | |
| 1395 | /* |
| 1396 | * Copy the data in. |
| 1397 | * Unfortunately there is a bug in older versions of |
| 1398 | * the Linux PPP multilink reconstruction code where it |
| 1399 | * drops 0-length fragments. Therefore we make sure the |
| 1400 | * fragment has at least one byte of data. Any bytes |
| 1401 | * we add in this situation will end up as padding on the |
| 1402 | * end of the reconstructed packet. |
| 1403 | */ |
| 1404 | if (flen == 0) |
| 1405 | *skb_put(frag, 1) = 0; |
| 1406 | else |
| 1407 | memcpy(q + hdrlen, p, flen); |
| 1408 | |
| 1409 | /* try to send it down the channel */ |
| 1410 | chan = pch->chan; |
David S. Miller | b03efcf | 2005-07-08 14:57:23 -0700 | [diff] [blame] | 1411 | if (!skb_queue_empty(&pch->file.xq) || |
| 1412 | !chan->ops->start_xmit(chan, frag)) |
Paul Mackerras | 516cd15 | 2005-05-12 19:47:12 -0400 | [diff] [blame] | 1413 | skb_queue_tail(&pch->file.xq, frag); |
| 1414 | pch->had_frag = 1; |
| 1415 | p += flen; |
| 1416 | len -= flen; |
| 1417 | ++ppp->nxseq; |
| 1418 | bits = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1419 | spin_unlock_bh(&pch->downl); |
Paul Mackerras | 516cd15 | 2005-05-12 19:47:12 -0400 | [diff] [blame] | 1420 | |
| 1421 | if (--nbigger == 0 && fragsize > 0) |
| 1422 | --fragsize; |
| 1423 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1424 | ppp->nxchan = i; |
| 1425 | |
| 1426 | return 1; |
| 1427 | |
| 1428 | noskb: |
| 1429 | spin_unlock_bh(&pch->downl); |
| 1430 | if (ppp->debug & 1) |
| 1431 | printk(KERN_ERR "PPP: no memory (fragment)\n"); |
| 1432 | ++ppp->stats.tx_errors; |
| 1433 | ++ppp->nxseq; |
| 1434 | return 1; /* abandon the frame */ |
| 1435 | } |
| 1436 | #endif /* CONFIG_PPP_MULTILINK */ |
| 1437 | |
| 1438 | /* |
| 1439 | * Try to send data out on a channel. |
| 1440 | */ |
| 1441 | static void |
| 1442 | ppp_channel_push(struct channel *pch) |
| 1443 | { |
| 1444 | struct sk_buff *skb; |
| 1445 | struct ppp *ppp; |
| 1446 | |
| 1447 | spin_lock_bh(&pch->downl); |
| 1448 | if (pch->chan != 0) { |
David S. Miller | b03efcf | 2005-07-08 14:57:23 -0700 | [diff] [blame] | 1449 | while (!skb_queue_empty(&pch->file.xq)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1450 | skb = skb_dequeue(&pch->file.xq); |
| 1451 | if (!pch->chan->ops->start_xmit(pch->chan, skb)) { |
| 1452 | /* put the packet back and try again later */ |
| 1453 | skb_queue_head(&pch->file.xq, skb); |
| 1454 | break; |
| 1455 | } |
| 1456 | } |
| 1457 | } else { |
| 1458 | /* channel got deregistered */ |
| 1459 | skb_queue_purge(&pch->file.xq); |
| 1460 | } |
| 1461 | spin_unlock_bh(&pch->downl); |
| 1462 | /* see if there is anything from the attached unit to be sent */ |
David S. Miller | b03efcf | 2005-07-08 14:57:23 -0700 | [diff] [blame] | 1463 | if (skb_queue_empty(&pch->file.xq)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1464 | read_lock_bh(&pch->upl); |
| 1465 | ppp = pch->ppp; |
| 1466 | if (ppp != 0) |
| 1467 | ppp_xmit_process(ppp); |
| 1468 | read_unlock_bh(&pch->upl); |
| 1469 | } |
| 1470 | } |
| 1471 | |
| 1472 | /* |
| 1473 | * Receive-side routines. |
| 1474 | */ |
| 1475 | |
| 1476 | /* misuse a few fields of the skb for MP reconstruction */ |
| 1477 | #define sequence priority |
| 1478 | #define BEbits cb[0] |
| 1479 | |
| 1480 | static inline void |
| 1481 | ppp_do_recv(struct ppp *ppp, struct sk_buff *skb, struct channel *pch) |
| 1482 | { |
| 1483 | ppp_recv_lock(ppp); |
| 1484 | /* ppp->dev == 0 means interface is closing down */ |
| 1485 | if (ppp->dev != 0) |
| 1486 | ppp_receive_frame(ppp, skb, pch); |
| 1487 | else |
| 1488 | kfree_skb(skb); |
| 1489 | ppp_recv_unlock(ppp); |
| 1490 | } |
| 1491 | |
| 1492 | void |
| 1493 | ppp_input(struct ppp_channel *chan, struct sk_buff *skb) |
| 1494 | { |
| 1495 | struct channel *pch = chan->ppp; |
| 1496 | int proto; |
| 1497 | |
| 1498 | if (pch == 0 || skb->len == 0) { |
| 1499 | kfree_skb(skb); |
| 1500 | return; |
| 1501 | } |
Paul Mackerras | 516cd15 | 2005-05-12 19:47:12 -0400 | [diff] [blame] | 1502 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1503 | proto = PPP_PROTO(skb); |
| 1504 | read_lock_bh(&pch->upl); |
| 1505 | if (pch->ppp == 0 || proto >= 0xc000 || proto == PPP_CCPFRAG) { |
| 1506 | /* put it on the channel queue */ |
| 1507 | skb_queue_tail(&pch->file.rq, skb); |
| 1508 | /* drop old frames if queue too long */ |
| 1509 | while (pch->file.rq.qlen > PPP_MAX_RQLEN |
| 1510 | && (skb = skb_dequeue(&pch->file.rq)) != 0) |
| 1511 | kfree_skb(skb); |
| 1512 | wake_up_interruptible(&pch->file.rwait); |
| 1513 | } else { |
| 1514 | ppp_do_recv(pch->ppp, skb, pch); |
| 1515 | } |
| 1516 | read_unlock_bh(&pch->upl); |
| 1517 | } |
| 1518 | |
| 1519 | /* Put a 0-length skb in the receive queue as an error indication */ |
| 1520 | void |
| 1521 | ppp_input_error(struct ppp_channel *chan, int code) |
| 1522 | { |
| 1523 | struct channel *pch = chan->ppp; |
| 1524 | struct sk_buff *skb; |
| 1525 | |
| 1526 | if (pch == 0) |
| 1527 | return; |
| 1528 | |
| 1529 | read_lock_bh(&pch->upl); |
| 1530 | if (pch->ppp != 0) { |
| 1531 | skb = alloc_skb(0, GFP_ATOMIC); |
| 1532 | if (skb != 0) { |
| 1533 | skb->len = 0; /* probably unnecessary */ |
| 1534 | skb->cb[0] = code; |
| 1535 | ppp_do_recv(pch->ppp, skb, pch); |
| 1536 | } |
| 1537 | } |
| 1538 | read_unlock_bh(&pch->upl); |
| 1539 | } |
| 1540 | |
| 1541 | /* |
| 1542 | * We come in here to process a received frame. |
| 1543 | * The receive side of the ppp unit is locked. |
| 1544 | */ |
| 1545 | static void |
| 1546 | ppp_receive_frame(struct ppp *ppp, struct sk_buff *skb, struct channel *pch) |
| 1547 | { |
| 1548 | if (skb->len >= 2) { |
| 1549 | #ifdef CONFIG_PPP_MULTILINK |
| 1550 | /* XXX do channel-level decompression here */ |
| 1551 | if (PPP_PROTO(skb) == PPP_MP) |
| 1552 | ppp_receive_mp_frame(ppp, skb, pch); |
| 1553 | else |
| 1554 | #endif /* CONFIG_PPP_MULTILINK */ |
| 1555 | ppp_receive_nonmp_frame(ppp, skb); |
| 1556 | return; |
| 1557 | } |
| 1558 | |
| 1559 | if (skb->len > 0) |
| 1560 | /* note: a 0-length skb is used as an error indication */ |
| 1561 | ++ppp->stats.rx_length_errors; |
| 1562 | |
| 1563 | kfree_skb(skb); |
| 1564 | ppp_receive_error(ppp); |
| 1565 | } |
| 1566 | |
| 1567 | static void |
| 1568 | ppp_receive_error(struct ppp *ppp) |
| 1569 | { |
| 1570 | ++ppp->stats.rx_errors; |
| 1571 | if (ppp->vj != 0) |
| 1572 | slhc_toss(ppp->vj); |
| 1573 | } |
| 1574 | |
| 1575 | static void |
| 1576 | ppp_receive_nonmp_frame(struct ppp *ppp, struct sk_buff *skb) |
| 1577 | { |
| 1578 | struct sk_buff *ns; |
| 1579 | int proto, len, npi; |
| 1580 | |
| 1581 | /* |
| 1582 | * Decompress the frame, if compressed. |
| 1583 | * Note that some decompressors need to see uncompressed frames |
| 1584 | * that come in as well as compressed frames. |
| 1585 | */ |
| 1586 | if (ppp->rc_state != 0 && (ppp->rstate & SC_DECOMP_RUN) |
| 1587 | && (ppp->rstate & (SC_DC_FERROR | SC_DC_ERROR)) == 0) |
| 1588 | skb = ppp_decompress_frame(ppp, skb); |
| 1589 | |
Matt Domsch | b3f9b92 | 2005-11-08 09:40:47 -0800 | [diff] [blame] | 1590 | if (ppp->flags & SC_MUST_COMP && ppp->rstate & SC_DC_FERROR) |
| 1591 | goto err; |
| 1592 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1593 | proto = PPP_PROTO(skb); |
| 1594 | switch (proto) { |
| 1595 | case PPP_VJC_COMP: |
| 1596 | /* decompress VJ compressed packets */ |
| 1597 | if (ppp->vj == 0 || (ppp->flags & SC_REJ_COMP_TCP)) |
| 1598 | goto err; |
| 1599 | |
| 1600 | if (skb_tailroom(skb) < 124) { |
| 1601 | /* copy to a new sk_buff with more tailroom */ |
| 1602 | ns = dev_alloc_skb(skb->len + 128); |
| 1603 | if (ns == 0) { |
| 1604 | printk(KERN_ERR"PPP: no memory (VJ decomp)\n"); |
| 1605 | goto err; |
| 1606 | } |
| 1607 | skb_reserve(ns, 2); |
| 1608 | skb_copy_bits(skb, 0, skb_put(ns, skb->len), skb->len); |
| 1609 | kfree_skb(skb); |
| 1610 | skb = ns; |
| 1611 | } |
Herbert Xu | e3f749c | 2006-02-05 20:23:33 -0800 | [diff] [blame] | 1612 | else |
| 1613 | skb->ip_summed = CHECKSUM_NONE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1614 | |
| 1615 | len = slhc_uncompress(ppp->vj, skb->data + 2, skb->len - 2); |
| 1616 | if (len <= 0) { |
| 1617 | printk(KERN_DEBUG "PPP: VJ decompression error\n"); |
| 1618 | goto err; |
| 1619 | } |
| 1620 | len += 2; |
| 1621 | if (len > skb->len) |
| 1622 | skb_put(skb, len - skb->len); |
| 1623 | else if (len < skb->len) |
| 1624 | skb_trim(skb, len); |
| 1625 | proto = PPP_IP; |
| 1626 | break; |
| 1627 | |
| 1628 | case PPP_VJC_UNCOMP: |
| 1629 | if (ppp->vj == 0 || (ppp->flags & SC_REJ_COMP_TCP)) |
| 1630 | goto err; |
| 1631 | |
| 1632 | /* Until we fix the decompressor need to make sure |
| 1633 | * data portion is linear. |
| 1634 | */ |
| 1635 | if (!pskb_may_pull(skb, skb->len)) |
| 1636 | goto err; |
| 1637 | |
| 1638 | if (slhc_remember(ppp->vj, skb->data + 2, skb->len - 2) <= 0) { |
| 1639 | printk(KERN_ERR "PPP: VJ uncompressed error\n"); |
| 1640 | goto err; |
| 1641 | } |
| 1642 | proto = PPP_IP; |
| 1643 | break; |
| 1644 | |
| 1645 | case PPP_CCP: |
| 1646 | ppp_ccp_peek(ppp, skb, 1); |
| 1647 | break; |
| 1648 | } |
| 1649 | |
| 1650 | ++ppp->stats.rx_packets; |
| 1651 | ppp->stats.rx_bytes += skb->len - 2; |
| 1652 | |
| 1653 | npi = proto_to_npindex(proto); |
| 1654 | if (npi < 0) { |
| 1655 | /* control or unknown frame - pass it to pppd */ |
| 1656 | skb_queue_tail(&ppp->file.rq, skb); |
| 1657 | /* limit queue length by dropping old frames */ |
| 1658 | while (ppp->file.rq.qlen > PPP_MAX_RQLEN |
| 1659 | && (skb = skb_dequeue(&ppp->file.rq)) != 0) |
| 1660 | kfree_skb(skb); |
| 1661 | /* wake up any process polling or blocking on read */ |
| 1662 | wake_up_interruptible(&ppp->file.rwait); |
| 1663 | |
| 1664 | } else { |
| 1665 | /* network protocol frame - give it to the kernel */ |
| 1666 | |
| 1667 | #ifdef CONFIG_PPP_FILTER |
| 1668 | /* check if the packet passes the pass and active filters */ |
| 1669 | /* the filter instructions are constructed assuming |
| 1670 | a four-byte PPP header on each packet */ |
| 1671 | *skb_push(skb, 2) = 0; |
| 1672 | if (ppp->pass_filter |
| 1673 | && sk_run_filter(skb, ppp->pass_filter, |
| 1674 | ppp->pass_len) == 0) { |
| 1675 | if (ppp->debug & 1) |
| 1676 | printk(KERN_DEBUG "PPP: inbound frame not passed\n"); |
| 1677 | kfree_skb(skb); |
| 1678 | return; |
| 1679 | } |
| 1680 | if (!(ppp->active_filter |
| 1681 | && sk_run_filter(skb, ppp->active_filter, |
| 1682 | ppp->active_len) == 0)) |
| 1683 | ppp->last_recv = jiffies; |
| 1684 | skb_pull(skb, 2); |
| 1685 | #else |
| 1686 | ppp->last_recv = jiffies; |
| 1687 | #endif /* CONFIG_PPP_FILTER */ |
| 1688 | |
| 1689 | if ((ppp->dev->flags & IFF_UP) == 0 |
| 1690 | || ppp->npmode[npi] != NPMODE_PASS) { |
| 1691 | kfree_skb(skb); |
| 1692 | } else { |
Herbert Xu | cbb042f | 2006-03-20 22:43:56 -0800 | [diff] [blame] | 1693 | /* chop off protocol */ |
| 1694 | skb_pull_rcsum(skb, 2); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1695 | skb->dev = ppp->dev; |
| 1696 | skb->protocol = htons(npindex_to_ethertype[npi]); |
| 1697 | skb->mac.raw = skb->data; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1698 | netif_rx(skb); |
| 1699 | ppp->dev->last_rx = jiffies; |
| 1700 | } |
| 1701 | } |
| 1702 | return; |
| 1703 | |
| 1704 | err: |
| 1705 | kfree_skb(skb); |
| 1706 | ppp_receive_error(ppp); |
| 1707 | } |
| 1708 | |
| 1709 | static struct sk_buff * |
| 1710 | ppp_decompress_frame(struct ppp *ppp, struct sk_buff *skb) |
| 1711 | { |
| 1712 | int proto = PPP_PROTO(skb); |
| 1713 | struct sk_buff *ns; |
| 1714 | int len; |
| 1715 | |
| 1716 | /* Until we fix all the decompressor's need to make sure |
| 1717 | * data portion is linear. |
| 1718 | */ |
| 1719 | if (!pskb_may_pull(skb, skb->len)) |
| 1720 | goto err; |
| 1721 | |
| 1722 | if (proto == PPP_COMP) { |
| 1723 | ns = dev_alloc_skb(ppp->mru + PPP_HDRLEN); |
| 1724 | if (ns == 0) { |
| 1725 | printk(KERN_ERR "ppp_decompress_frame: no memory\n"); |
| 1726 | goto err; |
| 1727 | } |
| 1728 | /* the decompressor still expects the A/C bytes in the hdr */ |
| 1729 | len = ppp->rcomp->decompress(ppp->rc_state, skb->data - 2, |
| 1730 | skb->len + 2, ns->data, ppp->mru + PPP_HDRLEN); |
| 1731 | if (len < 0) { |
| 1732 | /* Pass the compressed frame to pppd as an |
| 1733 | error indication. */ |
| 1734 | if (len == DECOMP_FATALERROR) |
| 1735 | ppp->rstate |= SC_DC_FERROR; |
| 1736 | kfree_skb(ns); |
| 1737 | goto err; |
| 1738 | } |
| 1739 | |
| 1740 | kfree_skb(skb); |
| 1741 | skb = ns; |
| 1742 | skb_put(skb, len); |
| 1743 | skb_pull(skb, 2); /* pull off the A/C bytes */ |
| 1744 | |
| 1745 | } else { |
| 1746 | /* Uncompressed frame - pass to decompressor so it |
| 1747 | can update its dictionary if necessary. */ |
| 1748 | if (ppp->rcomp->incomp) |
| 1749 | ppp->rcomp->incomp(ppp->rc_state, skb->data - 2, |
| 1750 | skb->len + 2); |
| 1751 | } |
| 1752 | |
| 1753 | return skb; |
| 1754 | |
| 1755 | err: |
| 1756 | ppp->rstate |= SC_DC_ERROR; |
| 1757 | ppp_receive_error(ppp); |
| 1758 | return skb; |
| 1759 | } |
| 1760 | |
| 1761 | #ifdef CONFIG_PPP_MULTILINK |
| 1762 | /* |
| 1763 | * Receive a multilink frame. |
| 1764 | * We put it on the reconstruction queue and then pull off |
| 1765 | * as many completed frames as we can. |
| 1766 | */ |
| 1767 | static void |
| 1768 | ppp_receive_mp_frame(struct ppp *ppp, struct sk_buff *skb, struct channel *pch) |
| 1769 | { |
| 1770 | u32 mask, seq; |
Domen Puncer | 81616c5 | 2005-09-10 00:27:04 -0700 | [diff] [blame] | 1771 | struct channel *ch; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1772 | int mphdrlen = (ppp->flags & SC_MP_SHORTSEQ)? MPHDRLEN_SSN: MPHDRLEN; |
| 1773 | |
Paul Mackerras | 516cd15 | 2005-05-12 19:47:12 -0400 | [diff] [blame] | 1774 | if (!pskb_may_pull(skb, mphdrlen) || ppp->mrru == 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1775 | goto err; /* no good, throw it away */ |
| 1776 | |
| 1777 | /* Decode sequence number and begin/end bits */ |
| 1778 | if (ppp->flags & SC_MP_SHORTSEQ) { |
| 1779 | seq = ((skb->data[2] & 0x0f) << 8) | skb->data[3]; |
| 1780 | mask = 0xfff; |
| 1781 | } else { |
| 1782 | seq = (skb->data[3] << 16) | (skb->data[4] << 8)| skb->data[5]; |
| 1783 | mask = 0xffffff; |
| 1784 | } |
| 1785 | skb->BEbits = skb->data[2]; |
| 1786 | skb_pull(skb, mphdrlen); /* pull off PPP and MP headers */ |
| 1787 | |
| 1788 | /* |
| 1789 | * Do protocol ID decompression on the first fragment of each packet. |
| 1790 | */ |
| 1791 | if ((skb->BEbits & B) && (skb->data[0] & 1)) |
| 1792 | *skb_push(skb, 1) = 0; |
| 1793 | |
| 1794 | /* |
| 1795 | * Expand sequence number to 32 bits, making it as close |
| 1796 | * as possible to ppp->minseq. |
| 1797 | */ |
| 1798 | seq |= ppp->minseq & ~mask; |
| 1799 | if ((int)(ppp->minseq - seq) > (int)(mask >> 1)) |
| 1800 | seq += mask + 1; |
| 1801 | else if ((int)(seq - ppp->minseq) > (int)(mask >> 1)) |
| 1802 | seq -= mask + 1; /* should never happen */ |
| 1803 | skb->sequence = seq; |
| 1804 | pch->lastseq = seq; |
| 1805 | |
| 1806 | /* |
| 1807 | * If this packet comes before the next one we were expecting, |
| 1808 | * drop it. |
| 1809 | */ |
| 1810 | if (seq_before(seq, ppp->nextseq)) { |
| 1811 | kfree_skb(skb); |
| 1812 | ++ppp->stats.rx_dropped; |
| 1813 | ppp_receive_error(ppp); |
| 1814 | return; |
| 1815 | } |
| 1816 | |
| 1817 | /* |
| 1818 | * Reevaluate minseq, the minimum over all channels of the |
| 1819 | * last sequence number received on each channel. Because of |
| 1820 | * the increasing sequence number rule, we know that any fragment |
| 1821 | * before `minseq' which hasn't arrived is never going to arrive. |
| 1822 | * The list of channels can't change because we have the receive |
| 1823 | * side of the ppp unit locked. |
| 1824 | */ |
Domen Puncer | 81616c5 | 2005-09-10 00:27:04 -0700 | [diff] [blame] | 1825 | list_for_each_entry(ch, &ppp->channels, clist) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1826 | if (seq_before(ch->lastseq, seq)) |
| 1827 | seq = ch->lastseq; |
| 1828 | } |
| 1829 | if (seq_before(ppp->minseq, seq)) |
| 1830 | ppp->minseq = seq; |
| 1831 | |
| 1832 | /* Put the fragment on the reconstruction queue */ |
| 1833 | ppp_mp_insert(ppp, skb); |
| 1834 | |
| 1835 | /* If the queue is getting long, don't wait any longer for packets |
| 1836 | before the start of the queue. */ |
| 1837 | if (skb_queue_len(&ppp->mrq) >= PPP_MP_MAX_QLEN |
| 1838 | && seq_before(ppp->minseq, ppp->mrq.next->sequence)) |
| 1839 | ppp->minseq = ppp->mrq.next->sequence; |
| 1840 | |
| 1841 | /* Pull completed packets off the queue and receive them. */ |
| 1842 | while ((skb = ppp_mp_reconstruct(ppp)) != 0) |
| 1843 | ppp_receive_nonmp_frame(ppp, skb); |
| 1844 | |
| 1845 | return; |
| 1846 | |
| 1847 | err: |
| 1848 | kfree_skb(skb); |
| 1849 | ppp_receive_error(ppp); |
| 1850 | } |
| 1851 | |
| 1852 | /* |
| 1853 | * Insert a fragment on the MP reconstruction queue. |
| 1854 | * The queue is ordered by increasing sequence number. |
| 1855 | */ |
| 1856 | static void |
| 1857 | ppp_mp_insert(struct ppp *ppp, struct sk_buff *skb) |
| 1858 | { |
| 1859 | struct sk_buff *p; |
| 1860 | struct sk_buff_head *list = &ppp->mrq; |
| 1861 | u32 seq = skb->sequence; |
| 1862 | |
| 1863 | /* N.B. we don't need to lock the list lock because we have the |
| 1864 | ppp unit receive-side lock. */ |
| 1865 | for (p = list->next; p != (struct sk_buff *)list; p = p->next) |
| 1866 | if (seq_before(seq, p->sequence)) |
| 1867 | break; |
| 1868 | __skb_insert(skb, p->prev, p, list); |
| 1869 | } |
| 1870 | |
| 1871 | /* |
| 1872 | * Reconstruct a packet from the MP fragment queue. |
| 1873 | * We go through increasing sequence numbers until we find a |
| 1874 | * complete packet, or we get to the sequence number for a fragment |
| 1875 | * which hasn't arrived but might still do so. |
| 1876 | */ |
| 1877 | struct sk_buff * |
| 1878 | ppp_mp_reconstruct(struct ppp *ppp) |
| 1879 | { |
| 1880 | u32 seq = ppp->nextseq; |
| 1881 | u32 minseq = ppp->minseq; |
| 1882 | struct sk_buff_head *list = &ppp->mrq; |
| 1883 | struct sk_buff *p, *next; |
| 1884 | struct sk_buff *head, *tail; |
| 1885 | struct sk_buff *skb = NULL; |
| 1886 | int lost = 0, len = 0; |
| 1887 | |
| 1888 | if (ppp->mrru == 0) /* do nothing until mrru is set */ |
| 1889 | return NULL; |
| 1890 | head = list->next; |
| 1891 | tail = NULL; |
| 1892 | for (p = head; p != (struct sk_buff *) list; p = next) { |
| 1893 | next = p->next; |
| 1894 | if (seq_before(p->sequence, seq)) { |
| 1895 | /* this can't happen, anyway ignore the skb */ |
| 1896 | printk(KERN_ERR "ppp_mp_reconstruct bad seq %u < %u\n", |
| 1897 | p->sequence, seq); |
| 1898 | head = next; |
| 1899 | continue; |
| 1900 | } |
| 1901 | if (p->sequence != seq) { |
| 1902 | /* Fragment `seq' is missing. If it is after |
| 1903 | minseq, it might arrive later, so stop here. */ |
| 1904 | if (seq_after(seq, minseq)) |
| 1905 | break; |
| 1906 | /* Fragment `seq' is lost, keep going. */ |
| 1907 | lost = 1; |
| 1908 | seq = seq_before(minseq, p->sequence)? |
| 1909 | minseq + 1: p->sequence; |
| 1910 | next = p; |
| 1911 | continue; |
| 1912 | } |
| 1913 | |
| 1914 | /* |
| 1915 | * At this point we know that all the fragments from |
| 1916 | * ppp->nextseq to seq are either present or lost. |
| 1917 | * Also, there are no complete packets in the queue |
| 1918 | * that have no missing fragments and end before this |
| 1919 | * fragment. |
| 1920 | */ |
| 1921 | |
| 1922 | /* B bit set indicates this fragment starts a packet */ |
| 1923 | if (p->BEbits & B) { |
| 1924 | head = p; |
| 1925 | lost = 0; |
| 1926 | len = 0; |
| 1927 | } |
| 1928 | |
| 1929 | len += p->len; |
| 1930 | |
| 1931 | /* Got a complete packet yet? */ |
| 1932 | if (lost == 0 && (p->BEbits & E) && (head->BEbits & B)) { |
| 1933 | if (len > ppp->mrru + 2) { |
| 1934 | ++ppp->stats.rx_length_errors; |
| 1935 | printk(KERN_DEBUG "PPP: reconstructed packet" |
| 1936 | " is too long (%d)\n", len); |
| 1937 | } else if (p == head) { |
| 1938 | /* fragment is complete packet - reuse skb */ |
| 1939 | tail = p; |
| 1940 | skb = skb_get(p); |
| 1941 | break; |
| 1942 | } else if ((skb = dev_alloc_skb(len)) == NULL) { |
| 1943 | ++ppp->stats.rx_missed_errors; |
| 1944 | printk(KERN_DEBUG "PPP: no memory for " |
| 1945 | "reconstructed packet"); |
| 1946 | } else { |
| 1947 | tail = p; |
| 1948 | break; |
| 1949 | } |
| 1950 | ppp->nextseq = seq + 1; |
| 1951 | } |
| 1952 | |
| 1953 | /* |
| 1954 | * If this is the ending fragment of a packet, |
| 1955 | * and we haven't found a complete valid packet yet, |
| 1956 | * we can discard up to and including this fragment. |
| 1957 | */ |
| 1958 | if (p->BEbits & E) |
| 1959 | head = next; |
| 1960 | |
| 1961 | ++seq; |
| 1962 | } |
| 1963 | |
| 1964 | /* If we have a complete packet, copy it all into one skb. */ |
| 1965 | if (tail != NULL) { |
| 1966 | /* If we have discarded any fragments, |
| 1967 | signal a receive error. */ |
| 1968 | if (head->sequence != ppp->nextseq) { |
| 1969 | if (ppp->debug & 1) |
| 1970 | printk(KERN_DEBUG " missed pkts %u..%u\n", |
| 1971 | ppp->nextseq, head->sequence-1); |
| 1972 | ++ppp->stats.rx_dropped; |
| 1973 | ppp_receive_error(ppp); |
| 1974 | } |
| 1975 | |
| 1976 | if (head != tail) |
| 1977 | /* copy to a single skb */ |
| 1978 | for (p = head; p != tail->next; p = p->next) |
| 1979 | skb_copy_bits(p, 0, skb_put(skb, p->len), p->len); |
| 1980 | ppp->nextseq = tail->sequence + 1; |
| 1981 | head = tail->next; |
| 1982 | } |
| 1983 | |
| 1984 | /* Discard all the skbuffs that we have copied the data out of |
| 1985 | or that we can't use. */ |
| 1986 | while ((p = list->next) != head) { |
| 1987 | __skb_unlink(p, list); |
| 1988 | kfree_skb(p); |
| 1989 | } |
| 1990 | |
| 1991 | return skb; |
| 1992 | } |
| 1993 | #endif /* CONFIG_PPP_MULTILINK */ |
| 1994 | |
| 1995 | /* |
| 1996 | * Channel interface. |
| 1997 | */ |
| 1998 | |
| 1999 | /* |
| 2000 | * Create a new, unattached ppp channel. |
| 2001 | */ |
| 2002 | int |
| 2003 | ppp_register_channel(struct ppp_channel *chan) |
| 2004 | { |
| 2005 | struct channel *pch; |
| 2006 | |
| 2007 | pch = kmalloc(sizeof(struct channel), GFP_KERNEL); |
| 2008 | if (pch == 0) |
| 2009 | return -ENOMEM; |
| 2010 | memset(pch, 0, sizeof(struct channel)); |
| 2011 | pch->ppp = NULL; |
| 2012 | pch->chan = chan; |
| 2013 | chan->ppp = pch; |
| 2014 | init_ppp_file(&pch->file, CHANNEL); |
| 2015 | pch->file.hdrlen = chan->hdrlen; |
| 2016 | #ifdef CONFIG_PPP_MULTILINK |
| 2017 | pch->lastseq = -1; |
| 2018 | #endif /* CONFIG_PPP_MULTILINK */ |
| 2019 | init_rwsem(&pch->chan_sem); |
| 2020 | spin_lock_init(&pch->downl); |
| 2021 | rwlock_init(&pch->upl); |
| 2022 | spin_lock_bh(&all_channels_lock); |
| 2023 | pch->file.index = ++last_channel_index; |
| 2024 | list_add(&pch->list, &new_channels); |
| 2025 | atomic_inc(&channel_count); |
| 2026 | spin_unlock_bh(&all_channels_lock); |
| 2027 | return 0; |
| 2028 | } |
| 2029 | |
| 2030 | /* |
| 2031 | * Return the index of a channel. |
| 2032 | */ |
| 2033 | int ppp_channel_index(struct ppp_channel *chan) |
| 2034 | { |
| 2035 | struct channel *pch = chan->ppp; |
| 2036 | |
| 2037 | if (pch != 0) |
| 2038 | return pch->file.index; |
| 2039 | return -1; |
| 2040 | } |
| 2041 | |
| 2042 | /* |
| 2043 | * Return the PPP unit number to which a channel is connected. |
| 2044 | */ |
| 2045 | int ppp_unit_number(struct ppp_channel *chan) |
| 2046 | { |
| 2047 | struct channel *pch = chan->ppp; |
| 2048 | int unit = -1; |
| 2049 | |
| 2050 | if (pch != 0) { |
| 2051 | read_lock_bh(&pch->upl); |
| 2052 | if (pch->ppp != 0) |
| 2053 | unit = pch->ppp->file.index; |
| 2054 | read_unlock_bh(&pch->upl); |
| 2055 | } |
| 2056 | return unit; |
| 2057 | } |
| 2058 | |
| 2059 | /* |
| 2060 | * Disconnect a channel from the generic layer. |
| 2061 | * This must be called in process context. |
| 2062 | */ |
| 2063 | void |
| 2064 | ppp_unregister_channel(struct ppp_channel *chan) |
| 2065 | { |
| 2066 | struct channel *pch = chan->ppp; |
| 2067 | |
| 2068 | if (pch == 0) |
| 2069 | return; /* should never happen */ |
| 2070 | chan->ppp = NULL; |
| 2071 | |
| 2072 | /* |
| 2073 | * This ensures that we have returned from any calls into the |
| 2074 | * the channel's start_xmit or ioctl routine before we proceed. |
| 2075 | */ |
| 2076 | down_write(&pch->chan_sem); |
| 2077 | spin_lock_bh(&pch->downl); |
| 2078 | pch->chan = NULL; |
| 2079 | spin_unlock_bh(&pch->downl); |
| 2080 | up_write(&pch->chan_sem); |
| 2081 | ppp_disconnect_channel(pch); |
| 2082 | spin_lock_bh(&all_channels_lock); |
| 2083 | list_del(&pch->list); |
| 2084 | spin_unlock_bh(&all_channels_lock); |
| 2085 | pch->file.dead = 1; |
| 2086 | wake_up_interruptible(&pch->file.rwait); |
| 2087 | if (atomic_dec_and_test(&pch->file.refcnt)) |
| 2088 | ppp_destroy_channel(pch); |
| 2089 | } |
| 2090 | |
| 2091 | /* |
| 2092 | * Callback from a channel when it can accept more to transmit. |
| 2093 | * This should be called at BH/softirq level, not interrupt level. |
| 2094 | */ |
| 2095 | void |
| 2096 | ppp_output_wakeup(struct ppp_channel *chan) |
| 2097 | { |
| 2098 | struct channel *pch = chan->ppp; |
| 2099 | |
| 2100 | if (pch == 0) |
| 2101 | return; |
| 2102 | ppp_channel_push(pch); |
| 2103 | } |
| 2104 | |
| 2105 | /* |
| 2106 | * Compression control. |
| 2107 | */ |
| 2108 | |
| 2109 | /* Process the PPPIOCSCOMPRESS ioctl. */ |
| 2110 | static int |
| 2111 | ppp_set_compress(struct ppp *ppp, unsigned long arg) |
| 2112 | { |
| 2113 | int err; |
| 2114 | struct compressor *cp, *ocomp; |
| 2115 | struct ppp_option_data data; |
| 2116 | void *state, *ostate; |
| 2117 | unsigned char ccp_option[CCP_MAX_OPTION_LENGTH]; |
| 2118 | |
| 2119 | err = -EFAULT; |
| 2120 | if (copy_from_user(&data, (void __user *) arg, sizeof(data)) |
| 2121 | || (data.length <= CCP_MAX_OPTION_LENGTH |
| 2122 | && copy_from_user(ccp_option, (void __user *) data.ptr, data.length))) |
| 2123 | goto out; |
| 2124 | err = -EINVAL; |
| 2125 | if (data.length > CCP_MAX_OPTION_LENGTH |
| 2126 | || ccp_option[1] < 2 || ccp_option[1] > data.length) |
| 2127 | goto out; |
| 2128 | |
| 2129 | cp = find_compressor(ccp_option[0]); |
| 2130 | #ifdef CONFIG_KMOD |
| 2131 | if (cp == 0) { |
| 2132 | request_module("ppp-compress-%d", ccp_option[0]); |
| 2133 | cp = find_compressor(ccp_option[0]); |
| 2134 | } |
| 2135 | #endif /* CONFIG_KMOD */ |
| 2136 | if (cp == 0) |
| 2137 | goto out; |
| 2138 | |
| 2139 | err = -ENOBUFS; |
| 2140 | if (data.transmit) { |
| 2141 | state = cp->comp_alloc(ccp_option, data.length); |
| 2142 | if (state != 0) { |
| 2143 | ppp_xmit_lock(ppp); |
| 2144 | ppp->xstate &= ~SC_COMP_RUN; |
| 2145 | ocomp = ppp->xcomp; |
| 2146 | ostate = ppp->xc_state; |
| 2147 | ppp->xcomp = cp; |
| 2148 | ppp->xc_state = state; |
| 2149 | ppp_xmit_unlock(ppp); |
| 2150 | if (ostate != 0) { |
| 2151 | ocomp->comp_free(ostate); |
| 2152 | module_put(ocomp->owner); |
| 2153 | } |
| 2154 | err = 0; |
| 2155 | } else |
| 2156 | module_put(cp->owner); |
| 2157 | |
| 2158 | } else { |
| 2159 | state = cp->decomp_alloc(ccp_option, data.length); |
| 2160 | if (state != 0) { |
| 2161 | ppp_recv_lock(ppp); |
| 2162 | ppp->rstate &= ~SC_DECOMP_RUN; |
| 2163 | ocomp = ppp->rcomp; |
| 2164 | ostate = ppp->rc_state; |
| 2165 | ppp->rcomp = cp; |
| 2166 | ppp->rc_state = state; |
| 2167 | ppp_recv_unlock(ppp); |
| 2168 | if (ostate != 0) { |
| 2169 | ocomp->decomp_free(ostate); |
| 2170 | module_put(ocomp->owner); |
| 2171 | } |
| 2172 | err = 0; |
| 2173 | } else |
| 2174 | module_put(cp->owner); |
| 2175 | } |
| 2176 | |
| 2177 | out: |
| 2178 | return err; |
| 2179 | } |
| 2180 | |
| 2181 | /* |
| 2182 | * Look at a CCP packet and update our state accordingly. |
| 2183 | * We assume the caller has the xmit or recv path locked. |
| 2184 | */ |
| 2185 | static void |
| 2186 | ppp_ccp_peek(struct ppp *ppp, struct sk_buff *skb, int inbound) |
| 2187 | { |
| 2188 | unsigned char *dp; |
| 2189 | int len; |
| 2190 | |
| 2191 | if (!pskb_may_pull(skb, CCP_HDRLEN + 2)) |
| 2192 | return; /* no header */ |
| 2193 | dp = skb->data + 2; |
| 2194 | |
| 2195 | switch (CCP_CODE(dp)) { |
| 2196 | case CCP_CONFREQ: |
| 2197 | |
| 2198 | /* A ConfReq starts negotiation of compression |
| 2199 | * in one direction of transmission, |
| 2200 | * and hence brings it down...but which way? |
| 2201 | * |
| 2202 | * Remember: |
| 2203 | * A ConfReq indicates what the sender would like to receive |
| 2204 | */ |
| 2205 | if(inbound) |
| 2206 | /* He is proposing what I should send */ |
| 2207 | ppp->xstate &= ~SC_COMP_RUN; |
| 2208 | else |
| 2209 | /* I am proposing to what he should send */ |
| 2210 | ppp->rstate &= ~SC_DECOMP_RUN; |
| 2211 | |
| 2212 | break; |
| 2213 | |
| 2214 | case CCP_TERMREQ: |
| 2215 | case CCP_TERMACK: |
| 2216 | /* |
| 2217 | * CCP is going down, both directions of transmission |
| 2218 | */ |
| 2219 | ppp->rstate &= ~SC_DECOMP_RUN; |
| 2220 | ppp->xstate &= ~SC_COMP_RUN; |
| 2221 | break; |
| 2222 | |
| 2223 | case CCP_CONFACK: |
| 2224 | if ((ppp->flags & (SC_CCP_OPEN | SC_CCP_UP)) != SC_CCP_OPEN) |
| 2225 | break; |
| 2226 | len = CCP_LENGTH(dp); |
| 2227 | if (!pskb_may_pull(skb, len + 2)) |
| 2228 | return; /* too short */ |
| 2229 | dp += CCP_HDRLEN; |
| 2230 | len -= CCP_HDRLEN; |
| 2231 | if (len < CCP_OPT_MINLEN || len < CCP_OPT_LENGTH(dp)) |
| 2232 | break; |
| 2233 | if (inbound) { |
| 2234 | /* we will start receiving compressed packets */ |
| 2235 | if (ppp->rc_state == 0) |
| 2236 | break; |
| 2237 | if (ppp->rcomp->decomp_init(ppp->rc_state, dp, len, |
| 2238 | ppp->file.index, 0, ppp->mru, ppp->debug)) { |
| 2239 | ppp->rstate |= SC_DECOMP_RUN; |
| 2240 | ppp->rstate &= ~(SC_DC_ERROR | SC_DC_FERROR); |
| 2241 | } |
| 2242 | } else { |
| 2243 | /* we will soon start sending compressed packets */ |
| 2244 | if (ppp->xc_state == 0) |
| 2245 | break; |
| 2246 | if (ppp->xcomp->comp_init(ppp->xc_state, dp, len, |
| 2247 | ppp->file.index, 0, ppp->debug)) |
| 2248 | ppp->xstate |= SC_COMP_RUN; |
| 2249 | } |
| 2250 | break; |
| 2251 | |
| 2252 | case CCP_RESETACK: |
| 2253 | /* reset the [de]compressor */ |
| 2254 | if ((ppp->flags & SC_CCP_UP) == 0) |
| 2255 | break; |
| 2256 | if (inbound) { |
| 2257 | if (ppp->rc_state && (ppp->rstate & SC_DECOMP_RUN)) { |
| 2258 | ppp->rcomp->decomp_reset(ppp->rc_state); |
| 2259 | ppp->rstate &= ~SC_DC_ERROR; |
| 2260 | } |
| 2261 | } else { |
| 2262 | if (ppp->xc_state && (ppp->xstate & SC_COMP_RUN)) |
| 2263 | ppp->xcomp->comp_reset(ppp->xc_state); |
| 2264 | } |
| 2265 | break; |
| 2266 | } |
| 2267 | } |
| 2268 | |
| 2269 | /* Free up compression resources. */ |
| 2270 | static void |
| 2271 | ppp_ccp_closed(struct ppp *ppp) |
| 2272 | { |
| 2273 | void *xstate, *rstate; |
| 2274 | struct compressor *xcomp, *rcomp; |
| 2275 | |
| 2276 | ppp_lock(ppp); |
| 2277 | ppp->flags &= ~(SC_CCP_OPEN | SC_CCP_UP); |
| 2278 | ppp->xstate = 0; |
| 2279 | xcomp = ppp->xcomp; |
| 2280 | xstate = ppp->xc_state; |
| 2281 | ppp->xc_state = NULL; |
| 2282 | ppp->rstate = 0; |
| 2283 | rcomp = ppp->rcomp; |
| 2284 | rstate = ppp->rc_state; |
| 2285 | ppp->rc_state = NULL; |
| 2286 | ppp_unlock(ppp); |
| 2287 | |
| 2288 | if (xstate) { |
| 2289 | xcomp->comp_free(xstate); |
| 2290 | module_put(xcomp->owner); |
| 2291 | } |
| 2292 | if (rstate) { |
| 2293 | rcomp->decomp_free(rstate); |
| 2294 | module_put(rcomp->owner); |
| 2295 | } |
| 2296 | } |
| 2297 | |
| 2298 | /* List of compressors. */ |
| 2299 | static LIST_HEAD(compressor_list); |
| 2300 | static DEFINE_SPINLOCK(compressor_list_lock); |
| 2301 | |
| 2302 | struct compressor_entry { |
| 2303 | struct list_head list; |
| 2304 | struct compressor *comp; |
| 2305 | }; |
| 2306 | |
| 2307 | static struct compressor_entry * |
| 2308 | find_comp_entry(int proto) |
| 2309 | { |
| 2310 | struct compressor_entry *ce; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2311 | |
Domen Puncer | 81616c5 | 2005-09-10 00:27:04 -0700 | [diff] [blame] | 2312 | list_for_each_entry(ce, &compressor_list, list) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2313 | if (ce->comp->compress_proto == proto) |
| 2314 | return ce; |
| 2315 | } |
| 2316 | return NULL; |
| 2317 | } |
| 2318 | |
| 2319 | /* Register a compressor */ |
| 2320 | int |
| 2321 | ppp_register_compressor(struct compressor *cp) |
| 2322 | { |
| 2323 | struct compressor_entry *ce; |
| 2324 | int ret; |
| 2325 | spin_lock(&compressor_list_lock); |
| 2326 | ret = -EEXIST; |
| 2327 | if (find_comp_entry(cp->compress_proto) != 0) |
| 2328 | goto out; |
| 2329 | ret = -ENOMEM; |
| 2330 | ce = kmalloc(sizeof(struct compressor_entry), GFP_ATOMIC); |
| 2331 | if (ce == 0) |
| 2332 | goto out; |
| 2333 | ret = 0; |
| 2334 | ce->comp = cp; |
| 2335 | list_add(&ce->list, &compressor_list); |
| 2336 | out: |
| 2337 | spin_unlock(&compressor_list_lock); |
| 2338 | return ret; |
| 2339 | } |
| 2340 | |
| 2341 | /* Unregister a compressor */ |
| 2342 | void |
| 2343 | ppp_unregister_compressor(struct compressor *cp) |
| 2344 | { |
| 2345 | struct compressor_entry *ce; |
| 2346 | |
| 2347 | spin_lock(&compressor_list_lock); |
| 2348 | ce = find_comp_entry(cp->compress_proto); |
| 2349 | if (ce != 0 && ce->comp == cp) { |
| 2350 | list_del(&ce->list); |
| 2351 | kfree(ce); |
| 2352 | } |
| 2353 | spin_unlock(&compressor_list_lock); |
| 2354 | } |
| 2355 | |
| 2356 | /* Find a compressor. */ |
| 2357 | static struct compressor * |
| 2358 | find_compressor(int type) |
| 2359 | { |
| 2360 | struct compressor_entry *ce; |
| 2361 | struct compressor *cp = NULL; |
| 2362 | |
| 2363 | spin_lock(&compressor_list_lock); |
| 2364 | ce = find_comp_entry(type); |
| 2365 | if (ce != 0) { |
| 2366 | cp = ce->comp; |
| 2367 | if (!try_module_get(cp->owner)) |
| 2368 | cp = NULL; |
| 2369 | } |
| 2370 | spin_unlock(&compressor_list_lock); |
| 2371 | return cp; |
| 2372 | } |
| 2373 | |
| 2374 | /* |
| 2375 | * Miscelleneous stuff. |
| 2376 | */ |
| 2377 | |
| 2378 | static void |
| 2379 | ppp_get_stats(struct ppp *ppp, struct ppp_stats *st) |
| 2380 | { |
| 2381 | struct slcompress *vj = ppp->vj; |
| 2382 | |
| 2383 | memset(st, 0, sizeof(*st)); |
| 2384 | st->p.ppp_ipackets = ppp->stats.rx_packets; |
| 2385 | st->p.ppp_ierrors = ppp->stats.rx_errors; |
| 2386 | st->p.ppp_ibytes = ppp->stats.rx_bytes; |
| 2387 | st->p.ppp_opackets = ppp->stats.tx_packets; |
| 2388 | st->p.ppp_oerrors = ppp->stats.tx_errors; |
| 2389 | st->p.ppp_obytes = ppp->stats.tx_bytes; |
| 2390 | if (vj == 0) |
| 2391 | return; |
| 2392 | st->vj.vjs_packets = vj->sls_o_compressed + vj->sls_o_uncompressed; |
| 2393 | st->vj.vjs_compressed = vj->sls_o_compressed; |
| 2394 | st->vj.vjs_searches = vj->sls_o_searches; |
| 2395 | st->vj.vjs_misses = vj->sls_o_misses; |
| 2396 | st->vj.vjs_errorin = vj->sls_i_error; |
| 2397 | st->vj.vjs_tossed = vj->sls_i_tossed; |
| 2398 | st->vj.vjs_uncompressedin = vj->sls_i_uncompressed; |
| 2399 | st->vj.vjs_compressedin = vj->sls_i_compressed; |
| 2400 | } |
| 2401 | |
| 2402 | /* |
| 2403 | * Stuff for handling the lists of ppp units and channels |
| 2404 | * and for initialization. |
| 2405 | */ |
| 2406 | |
| 2407 | /* |
| 2408 | * Create a new ppp interface unit. Fails if it can't allocate memory |
| 2409 | * or if there is already a unit with the requested number. |
| 2410 | * unit == -1 means allocate a new number. |
| 2411 | */ |
| 2412 | static struct ppp * |
| 2413 | ppp_create_interface(int unit, int *retp) |
| 2414 | { |
| 2415 | struct ppp *ppp; |
| 2416 | struct net_device *dev = NULL; |
| 2417 | int ret = -ENOMEM; |
| 2418 | int i; |
| 2419 | |
| 2420 | ppp = kmalloc(sizeof(struct ppp), GFP_KERNEL); |
| 2421 | if (!ppp) |
| 2422 | goto out; |
| 2423 | dev = alloc_netdev(0, "", ppp_setup); |
| 2424 | if (!dev) |
| 2425 | goto out1; |
| 2426 | memset(ppp, 0, sizeof(struct ppp)); |
| 2427 | |
| 2428 | ppp->mru = PPP_MRU; |
| 2429 | init_ppp_file(&ppp->file, INTERFACE); |
| 2430 | ppp->file.hdrlen = PPP_HDRLEN - 2; /* don't count proto bytes */ |
| 2431 | for (i = 0; i < NUM_NP; ++i) |
| 2432 | ppp->npmode[i] = NPMODE_PASS; |
| 2433 | INIT_LIST_HEAD(&ppp->channels); |
| 2434 | spin_lock_init(&ppp->rlock); |
| 2435 | spin_lock_init(&ppp->wlock); |
| 2436 | #ifdef CONFIG_PPP_MULTILINK |
| 2437 | ppp->minseq = -1; |
| 2438 | skb_queue_head_init(&ppp->mrq); |
| 2439 | #endif /* CONFIG_PPP_MULTILINK */ |
| 2440 | ppp->dev = dev; |
| 2441 | dev->priv = ppp; |
| 2442 | |
| 2443 | dev->hard_start_xmit = ppp_start_xmit; |
| 2444 | dev->get_stats = ppp_net_stats; |
| 2445 | dev->do_ioctl = ppp_net_ioctl; |
| 2446 | |
| 2447 | ret = -EEXIST; |
Arjan van de Ven | 8ed965d | 2006-03-23 03:00:21 -0800 | [diff] [blame] | 2448 | mutex_lock(&all_ppp_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2449 | if (unit < 0) |
| 2450 | unit = cardmap_find_first_free(all_ppp_units); |
| 2451 | else if (cardmap_get(all_ppp_units, unit) != NULL) |
| 2452 | goto out2; /* unit already exists */ |
| 2453 | |
| 2454 | /* Initialize the new ppp unit */ |
| 2455 | ppp->file.index = unit; |
| 2456 | sprintf(dev->name, "ppp%d", unit); |
| 2457 | |
| 2458 | ret = register_netdev(dev); |
| 2459 | if (ret != 0) { |
| 2460 | printk(KERN_ERR "PPP: couldn't register device %s (%d)\n", |
| 2461 | dev->name, ret); |
| 2462 | goto out2; |
| 2463 | } |
| 2464 | |
| 2465 | atomic_inc(&ppp_unit_count); |
| 2466 | cardmap_set(&all_ppp_units, unit, ppp); |
Arjan van de Ven | 8ed965d | 2006-03-23 03:00:21 -0800 | [diff] [blame] | 2467 | mutex_unlock(&all_ppp_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2468 | *retp = 0; |
| 2469 | return ppp; |
| 2470 | |
| 2471 | out2: |
Arjan van de Ven | 8ed965d | 2006-03-23 03:00:21 -0800 | [diff] [blame] | 2472 | mutex_unlock(&all_ppp_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2473 | free_netdev(dev); |
| 2474 | out1: |
| 2475 | kfree(ppp); |
| 2476 | out: |
| 2477 | *retp = ret; |
| 2478 | return NULL; |
| 2479 | } |
| 2480 | |
| 2481 | /* |
| 2482 | * Initialize a ppp_file structure. |
| 2483 | */ |
| 2484 | static void |
| 2485 | init_ppp_file(struct ppp_file *pf, int kind) |
| 2486 | { |
| 2487 | pf->kind = kind; |
| 2488 | skb_queue_head_init(&pf->xq); |
| 2489 | skb_queue_head_init(&pf->rq); |
| 2490 | atomic_set(&pf->refcnt, 1); |
| 2491 | init_waitqueue_head(&pf->rwait); |
| 2492 | } |
| 2493 | |
| 2494 | /* |
| 2495 | * Take down a ppp interface unit - called when the owning file |
| 2496 | * (the one that created the unit) is closed or detached. |
| 2497 | */ |
| 2498 | static void ppp_shutdown_interface(struct ppp *ppp) |
| 2499 | { |
| 2500 | struct net_device *dev; |
| 2501 | |
Arjan van de Ven | 8ed965d | 2006-03-23 03:00:21 -0800 | [diff] [blame] | 2502 | mutex_lock(&all_ppp_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2503 | ppp_lock(ppp); |
| 2504 | dev = ppp->dev; |
| 2505 | ppp->dev = NULL; |
| 2506 | ppp_unlock(ppp); |
| 2507 | /* This will call dev_close() for us. */ |
| 2508 | if (dev) { |
| 2509 | unregister_netdev(dev); |
| 2510 | free_netdev(dev); |
| 2511 | } |
| 2512 | cardmap_set(&all_ppp_units, ppp->file.index, NULL); |
| 2513 | ppp->file.dead = 1; |
| 2514 | ppp->owner = NULL; |
| 2515 | wake_up_interruptible(&ppp->file.rwait); |
Arjan van de Ven | 8ed965d | 2006-03-23 03:00:21 -0800 | [diff] [blame] | 2516 | mutex_unlock(&all_ppp_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2517 | } |
| 2518 | |
| 2519 | /* |
| 2520 | * Free the memory used by a ppp unit. This is only called once |
| 2521 | * there are no channels connected to the unit and no file structs |
| 2522 | * that reference the unit. |
| 2523 | */ |
| 2524 | static void ppp_destroy_interface(struct ppp *ppp) |
| 2525 | { |
| 2526 | atomic_dec(&ppp_unit_count); |
| 2527 | |
| 2528 | if (!ppp->file.dead || ppp->n_channels) { |
| 2529 | /* "can't happen" */ |
| 2530 | printk(KERN_ERR "ppp: destroying ppp struct %p but dead=%d " |
| 2531 | "n_channels=%d !\n", ppp, ppp->file.dead, |
| 2532 | ppp->n_channels); |
| 2533 | return; |
| 2534 | } |
| 2535 | |
| 2536 | ppp_ccp_closed(ppp); |
| 2537 | if (ppp->vj) { |
| 2538 | slhc_free(ppp->vj); |
| 2539 | ppp->vj = NULL; |
| 2540 | } |
| 2541 | skb_queue_purge(&ppp->file.xq); |
| 2542 | skb_queue_purge(&ppp->file.rq); |
| 2543 | #ifdef CONFIG_PPP_MULTILINK |
| 2544 | skb_queue_purge(&ppp->mrq); |
| 2545 | #endif /* CONFIG_PPP_MULTILINK */ |
| 2546 | #ifdef CONFIG_PPP_FILTER |
Jesper Juhl | 96edf83 | 2005-05-03 14:38:09 -0700 | [diff] [blame] | 2547 | kfree(ppp->pass_filter); |
| 2548 | ppp->pass_filter = NULL; |
| 2549 | kfree(ppp->active_filter); |
| 2550 | ppp->active_filter = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2551 | #endif /* CONFIG_PPP_FILTER */ |
| 2552 | |
| 2553 | kfree(ppp); |
| 2554 | } |
| 2555 | |
| 2556 | /* |
| 2557 | * Locate an existing ppp unit. |
Arjan van de Ven | 8ed965d | 2006-03-23 03:00:21 -0800 | [diff] [blame] | 2558 | * The caller should have locked the all_ppp_mutex. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2559 | */ |
| 2560 | static struct ppp * |
| 2561 | ppp_find_unit(int unit) |
| 2562 | { |
| 2563 | return cardmap_get(all_ppp_units, unit); |
| 2564 | } |
| 2565 | |
| 2566 | /* |
| 2567 | * Locate an existing ppp channel. |
| 2568 | * The caller should have locked the all_channels_lock. |
| 2569 | * First we look in the new_channels list, then in the |
| 2570 | * all_channels list. If found in the new_channels list, |
| 2571 | * we move it to the all_channels list. This is for speed |
| 2572 | * when we have a lot of channels in use. |
| 2573 | */ |
| 2574 | static struct channel * |
| 2575 | ppp_find_channel(int unit) |
| 2576 | { |
| 2577 | struct channel *pch; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2578 | |
Domen Puncer | 81616c5 | 2005-09-10 00:27:04 -0700 | [diff] [blame] | 2579 | list_for_each_entry(pch, &new_channels, list) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2580 | if (pch->file.index == unit) { |
| 2581 | list_del(&pch->list); |
| 2582 | list_add(&pch->list, &all_channels); |
| 2583 | return pch; |
| 2584 | } |
| 2585 | } |
Domen Puncer | 81616c5 | 2005-09-10 00:27:04 -0700 | [diff] [blame] | 2586 | list_for_each_entry(pch, &all_channels, list) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2587 | if (pch->file.index == unit) |
| 2588 | return pch; |
| 2589 | } |
| 2590 | return NULL; |
| 2591 | } |
| 2592 | |
| 2593 | /* |
| 2594 | * Connect a PPP channel to a PPP interface unit. |
| 2595 | */ |
| 2596 | static int |
| 2597 | ppp_connect_channel(struct channel *pch, int unit) |
| 2598 | { |
| 2599 | struct ppp *ppp; |
| 2600 | int ret = -ENXIO; |
| 2601 | int hdrlen; |
| 2602 | |
Arjan van de Ven | 8ed965d | 2006-03-23 03:00:21 -0800 | [diff] [blame] | 2603 | mutex_lock(&all_ppp_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2604 | ppp = ppp_find_unit(unit); |
| 2605 | if (ppp == 0) |
| 2606 | goto out; |
| 2607 | write_lock_bh(&pch->upl); |
| 2608 | ret = -EINVAL; |
| 2609 | if (pch->ppp != 0) |
| 2610 | goto outl; |
| 2611 | |
| 2612 | ppp_lock(ppp); |
| 2613 | if (pch->file.hdrlen > ppp->file.hdrlen) |
| 2614 | ppp->file.hdrlen = pch->file.hdrlen; |
| 2615 | hdrlen = pch->file.hdrlen + 2; /* for protocol bytes */ |
| 2616 | if (ppp->dev && hdrlen > ppp->dev->hard_header_len) |
| 2617 | ppp->dev->hard_header_len = hdrlen; |
| 2618 | list_add_tail(&pch->clist, &ppp->channels); |
| 2619 | ++ppp->n_channels; |
| 2620 | pch->ppp = ppp; |
| 2621 | atomic_inc(&ppp->file.refcnt); |
| 2622 | ppp_unlock(ppp); |
| 2623 | ret = 0; |
| 2624 | |
| 2625 | outl: |
| 2626 | write_unlock_bh(&pch->upl); |
| 2627 | out: |
Arjan van de Ven | 8ed965d | 2006-03-23 03:00:21 -0800 | [diff] [blame] | 2628 | mutex_unlock(&all_ppp_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2629 | return ret; |
| 2630 | } |
| 2631 | |
| 2632 | /* |
| 2633 | * Disconnect a channel from its ppp unit. |
| 2634 | */ |
| 2635 | static int |
| 2636 | ppp_disconnect_channel(struct channel *pch) |
| 2637 | { |
| 2638 | struct ppp *ppp; |
| 2639 | int err = -EINVAL; |
| 2640 | |
| 2641 | write_lock_bh(&pch->upl); |
| 2642 | ppp = pch->ppp; |
| 2643 | pch->ppp = NULL; |
| 2644 | write_unlock_bh(&pch->upl); |
| 2645 | if (ppp != 0) { |
| 2646 | /* remove it from the ppp unit's list */ |
| 2647 | ppp_lock(ppp); |
| 2648 | list_del(&pch->clist); |
| 2649 | if (--ppp->n_channels == 0) |
| 2650 | wake_up_interruptible(&ppp->file.rwait); |
| 2651 | ppp_unlock(ppp); |
| 2652 | if (atomic_dec_and_test(&ppp->file.refcnt)) |
| 2653 | ppp_destroy_interface(ppp); |
| 2654 | err = 0; |
| 2655 | } |
| 2656 | return err; |
| 2657 | } |
| 2658 | |
| 2659 | /* |
| 2660 | * Free up the resources used by a ppp channel. |
| 2661 | */ |
| 2662 | static void ppp_destroy_channel(struct channel *pch) |
| 2663 | { |
| 2664 | atomic_dec(&channel_count); |
| 2665 | |
| 2666 | if (!pch->file.dead) { |
| 2667 | /* "can't happen" */ |
| 2668 | printk(KERN_ERR "ppp: destroying undead channel %p !\n", |
| 2669 | pch); |
| 2670 | return; |
| 2671 | } |
| 2672 | skb_queue_purge(&pch->file.xq); |
| 2673 | skb_queue_purge(&pch->file.rq); |
| 2674 | kfree(pch); |
| 2675 | } |
| 2676 | |
| 2677 | static void __exit ppp_cleanup(void) |
| 2678 | { |
| 2679 | /* should never happen */ |
| 2680 | if (atomic_read(&ppp_unit_count) || atomic_read(&channel_count)) |
| 2681 | printk(KERN_ERR "PPP: removing module but units remain!\n"); |
| 2682 | cardmap_destroy(&all_ppp_units); |
| 2683 | if (unregister_chrdev(PPP_MAJOR, "ppp") != 0) |
| 2684 | printk(KERN_ERR "PPP: failed to unregister PPP device\n"); |
| 2685 | devfs_remove("ppp"); |
gregkh@suse.de | 56b2293 | 2005-03-23 10:01:41 -0800 | [diff] [blame] | 2686 | class_device_destroy(ppp_class, MKDEV(PPP_MAJOR, 0)); |
| 2687 | class_destroy(ppp_class); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2688 | } |
| 2689 | |
| 2690 | /* |
| 2691 | * Cardmap implementation. |
| 2692 | */ |
| 2693 | static void *cardmap_get(struct cardmap *map, unsigned int nr) |
| 2694 | { |
| 2695 | struct cardmap *p; |
| 2696 | int i; |
| 2697 | |
| 2698 | for (p = map; p != NULL; ) { |
| 2699 | if ((i = nr >> p->shift) >= CARDMAP_WIDTH) |
| 2700 | return NULL; |
| 2701 | if (p->shift == 0) |
| 2702 | return p->ptr[i]; |
| 2703 | nr &= ~(CARDMAP_MASK << p->shift); |
| 2704 | p = p->ptr[i]; |
| 2705 | } |
| 2706 | return NULL; |
| 2707 | } |
| 2708 | |
| 2709 | static void cardmap_set(struct cardmap **pmap, unsigned int nr, void *ptr) |
| 2710 | { |
| 2711 | struct cardmap *p; |
| 2712 | int i; |
| 2713 | |
| 2714 | p = *pmap; |
| 2715 | if (p == NULL || (nr >> p->shift) >= CARDMAP_WIDTH) { |
| 2716 | do { |
| 2717 | /* need a new top level */ |
| 2718 | struct cardmap *np = kmalloc(sizeof(*np), GFP_KERNEL); |
| 2719 | memset(np, 0, sizeof(*np)); |
| 2720 | np->ptr[0] = p; |
| 2721 | if (p != NULL) { |
| 2722 | np->shift = p->shift + CARDMAP_ORDER; |
| 2723 | p->parent = np; |
| 2724 | } else |
| 2725 | np->shift = 0; |
| 2726 | p = np; |
| 2727 | } while ((nr >> p->shift) >= CARDMAP_WIDTH); |
| 2728 | *pmap = p; |
| 2729 | } |
| 2730 | while (p->shift > 0) { |
| 2731 | i = (nr >> p->shift) & CARDMAP_MASK; |
| 2732 | if (p->ptr[i] == NULL) { |
| 2733 | struct cardmap *np = kmalloc(sizeof(*np), GFP_KERNEL); |
| 2734 | memset(np, 0, sizeof(*np)); |
| 2735 | np->shift = p->shift - CARDMAP_ORDER; |
| 2736 | np->parent = p; |
| 2737 | p->ptr[i] = np; |
| 2738 | } |
| 2739 | if (ptr == NULL) |
| 2740 | clear_bit(i, &p->inuse); |
| 2741 | p = p->ptr[i]; |
| 2742 | } |
| 2743 | i = nr & CARDMAP_MASK; |
| 2744 | p->ptr[i] = ptr; |
| 2745 | if (ptr != NULL) |
| 2746 | set_bit(i, &p->inuse); |
| 2747 | else |
| 2748 | clear_bit(i, &p->inuse); |
| 2749 | } |
| 2750 | |
| 2751 | static unsigned int cardmap_find_first_free(struct cardmap *map) |
| 2752 | { |
| 2753 | struct cardmap *p; |
| 2754 | unsigned int nr = 0; |
| 2755 | int i; |
| 2756 | |
| 2757 | if ((p = map) == NULL) |
| 2758 | return 0; |
| 2759 | for (;;) { |
| 2760 | i = find_first_zero_bit(&p->inuse, CARDMAP_WIDTH); |
| 2761 | if (i >= CARDMAP_WIDTH) { |
| 2762 | if (p->parent == NULL) |
| 2763 | return CARDMAP_WIDTH << p->shift; |
| 2764 | p = p->parent; |
| 2765 | i = (nr >> p->shift) & CARDMAP_MASK; |
| 2766 | set_bit(i, &p->inuse); |
| 2767 | continue; |
| 2768 | } |
| 2769 | nr = (nr & (~CARDMAP_MASK << p->shift)) | (i << p->shift); |
| 2770 | if (p->shift == 0 || p->ptr[i] == NULL) |
| 2771 | return nr; |
| 2772 | p = p->ptr[i]; |
| 2773 | } |
| 2774 | } |
| 2775 | |
| 2776 | static void cardmap_destroy(struct cardmap **pmap) |
| 2777 | { |
| 2778 | struct cardmap *p, *np; |
| 2779 | int i; |
| 2780 | |
| 2781 | for (p = *pmap; p != NULL; p = np) { |
| 2782 | if (p->shift != 0) { |
| 2783 | for (i = 0; i < CARDMAP_WIDTH; ++i) |
| 2784 | if (p->ptr[i] != NULL) |
| 2785 | break; |
| 2786 | if (i < CARDMAP_WIDTH) { |
| 2787 | np = p->ptr[i]; |
| 2788 | p->ptr[i] = NULL; |
| 2789 | continue; |
| 2790 | } |
| 2791 | } |
| 2792 | np = p->parent; |
| 2793 | kfree(p); |
| 2794 | } |
| 2795 | *pmap = NULL; |
| 2796 | } |
| 2797 | |
| 2798 | /* Module/initialization stuff */ |
| 2799 | |
| 2800 | module_init(ppp_init); |
| 2801 | module_exit(ppp_cleanup); |
| 2802 | |
| 2803 | EXPORT_SYMBOL(ppp_register_channel); |
| 2804 | EXPORT_SYMBOL(ppp_unregister_channel); |
| 2805 | EXPORT_SYMBOL(ppp_channel_index); |
| 2806 | EXPORT_SYMBOL(ppp_unit_number); |
| 2807 | EXPORT_SYMBOL(ppp_input); |
| 2808 | EXPORT_SYMBOL(ppp_input_error); |
| 2809 | EXPORT_SYMBOL(ppp_output_wakeup); |
| 2810 | EXPORT_SYMBOL(ppp_register_compressor); |
| 2811 | EXPORT_SYMBOL(ppp_unregister_compressor); |
| 2812 | MODULE_LICENSE("GPL"); |
| 2813 | MODULE_ALIAS_CHARDEV_MAJOR(PPP_MAJOR); |
| 2814 | MODULE_ALIAS("/dev/ppp"); |