| 1 | /* $NetBSD: ppp-deflate.c,v 1.23 2016/08/06 22:38:18 pgoyette Exp $ */ |
| 2 | /* Id: ppp-deflate.c,v 1.5 1997/03/04 03:33:28 paulus Exp */ |
| 3 | |
| 4 | /* |
| 5 | * ppp_deflate.c - interface the zlib procedures for Deflate compression |
| 6 | * and decompression (as used by gzip) to the PPP code. |
| 7 | * This version is for use with mbufs on BSD-derived systems. |
| 8 | * |
| 9 | * Copyright (c) 1989-2002 Paul Mackerras. All rights reserved. |
| 10 | * |
| 11 | * Redistribution and use in source and binary forms, with or without |
| 12 | * modification, are permitted provided that the following conditions |
| 13 | * are met: |
| 14 | * |
| 15 | * 1. Redistributions of source code must retain the above copyright |
| 16 | * notice, this list of conditions and the following disclaimer. |
| 17 | * |
| 18 | * 2. Redistributions in binary form must reproduce the above copyright |
| 19 | * notice, this list of conditions and the following disclaimer in |
| 20 | * the documentation and/or other materials provided with the |
| 21 | * distribution. |
| 22 | * |
| 23 | * 3. The name(s) of the authors of this software must not be used to |
| 24 | * endorse or promote products derived from this software without |
| 25 | * prior written permission. |
| 26 | * |
| 27 | * 4. Redistributions of any form whatsoever must retain the following |
| 28 | * acknowledgment: |
| 29 | * "This product includes software developed by Paul Mackerras |
| 30 | * <paulus@samba.org>". |
| 31 | * |
| 32 | * THE AUTHORS OF THIS SOFTWARE DISCLAIM ALL WARRANTIES WITH REGARD TO |
| 33 | * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY |
| 34 | * AND FITNESS, IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY |
| 35 | * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
| 36 | * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN |
| 37 | * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING |
| 38 | * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. |
| 39 | */ |
| 40 | |
| 41 | #include <sys/cdefs.h> |
| 42 | __KERNEL_RCSID(0, "$NetBSD: ppp-deflate.c,v 1.23 2016/08/06 22:38:18 pgoyette Exp $" ); |
| 43 | |
| 44 | #include <sys/param.h> |
| 45 | #include <sys/systm.h> |
| 46 | #include <sys/mbuf.h> |
| 47 | #include <sys/module.h> |
| 48 | #include <net/if.h> |
| 49 | #include <net/ppp_defs.h> |
| 50 | #include <net/if_ppp.h> |
| 51 | #include <net/zlib.h> |
| 52 | |
| 53 | #define PACKETPTR struct mbuf * |
| 54 | #include <net/ppp-comp.h> |
| 55 | |
| 56 | #if DO_DEFLATE |
| 57 | |
| 58 | #define DEFLATE_DEBUG 1 |
| 59 | |
| 60 | /* |
| 61 | * State for a Deflate (de)compressor. |
| 62 | */ |
| 63 | struct deflate_state { |
| 64 | int seqno; |
| 65 | int w_size; |
| 66 | int unit; |
| 67 | int hdrlen; |
| 68 | int mru; |
| 69 | int debug; |
| 70 | z_stream strm; |
| 71 | struct compstat stats; |
| 72 | }; |
| 73 | |
| 74 | #define DEFLATE_OVHD 2 /* Deflate overhead/packet */ |
| 75 | |
| 76 | static void *zalloc(void *, u_int items, u_int size); |
| 77 | static void zfree(void *, void *ptr); |
| 78 | static void *z_comp_alloc(u_char *options, int opt_len); |
| 79 | static void *z_decomp_alloc(u_char *options, int opt_len); |
| 80 | static void z_comp_free(void *state); |
| 81 | static void z_decomp_free(void *state); |
| 82 | static int z_comp_init(void *state, u_char *options, int opt_len, |
| 83 | int unit, int hdrlen, int debug); |
| 84 | static int z_decomp_init(void *state, u_char *options, int opt_len, |
| 85 | int unit, int hdrlen, int mru, int debug); |
| 86 | static int z_compress(void *state, struct mbuf **mret, |
| 87 | struct mbuf *mp, int slen, int maxolen); |
| 88 | static void z_incomp(void *state, struct mbuf *dmsg); |
| 89 | static int z_decompress(void *state, struct mbuf *cmp, |
| 90 | struct mbuf **dmpp); |
| 91 | static void z_comp_reset(void *state); |
| 92 | static void z_decomp_reset(void *state); |
| 93 | static void z_comp_stats(void *state, struct compstat *stats); |
| 94 | |
| 95 | /* |
| 96 | * Procedures exported to if_ppp.c. |
| 97 | */ |
| 98 | static struct compressor ppp_deflate[2] = { { |
| 99 | .compress_proto = CI_DEFLATE, |
| 100 | .comp_alloc = z_comp_alloc, |
| 101 | .comp_free = z_comp_free, |
| 102 | .comp_init = z_comp_init, |
| 103 | .comp_reset = z_comp_reset, |
| 104 | .compress = z_compress, |
| 105 | .comp_stat = z_comp_stats, |
| 106 | .decomp_alloc = z_decomp_alloc, |
| 107 | .decomp_free = z_decomp_free, |
| 108 | .decomp_init = z_decomp_init, |
| 109 | .decomp_reset = z_decomp_reset, |
| 110 | .decompress = z_decompress, |
| 111 | .incomp = z_incomp, |
| 112 | .decomp_stat = z_comp_stats, |
| 113 | }, |
| 114 | { |
| 115 | .compress_proto = CI_DEFLATE_DRAFT, |
| 116 | .comp_alloc = z_comp_alloc, |
| 117 | .comp_free = z_comp_free, |
| 118 | .comp_init = z_comp_init, |
| 119 | .comp_reset = z_comp_reset, |
| 120 | .compress = z_compress, |
| 121 | .comp_stat = z_comp_stats, |
| 122 | .decomp_alloc = z_decomp_alloc, |
| 123 | .decomp_free = z_decomp_free, |
| 124 | .decomp_init = z_decomp_init, |
| 125 | .decomp_reset = z_decomp_reset, |
| 126 | .decompress = z_decompress, |
| 127 | .incomp = z_incomp, |
| 128 | .decomp_stat = z_comp_stats, |
| 129 | } }; |
| 130 | /* |
| 131 | * Space allocation and freeing routines for use by zlib routines. |
| 132 | */ |
| 133 | void * |
| 134 | zalloc(void *notused, u_int items, u_int size) |
| 135 | { |
| 136 | void *ptr; |
| 137 | |
| 138 | ptr = malloc(items * size, M_DEVBUF, M_NOWAIT); |
| 139 | return ptr; |
| 140 | } |
| 141 | |
| 142 | void |
| 143 | zfree(void *notused, void *ptr) |
| 144 | { |
| 145 | free(ptr, M_DEVBUF); |
| 146 | } |
| 147 | |
| 148 | /* |
| 149 | * Allocate space for a compressor. |
| 150 | */ |
| 151 | static void * |
| 152 | z_comp_alloc(u_char *options, int opt_len) |
| 153 | { |
| 154 | struct deflate_state *state; |
| 155 | int w_size; |
| 156 | |
| 157 | if (opt_len != CILEN_DEFLATE |
| 158 | || (options[0] != CI_DEFLATE && options[0] != CI_DEFLATE_DRAFT) |
| 159 | || options[1] != CILEN_DEFLATE |
| 160 | || DEFLATE_METHOD(options[2]) != DEFLATE_METHOD_VAL |
| 161 | || options[3] != DEFLATE_CHK_SEQUENCE) |
| 162 | return NULL; |
| 163 | w_size = DEFLATE_SIZE(options[2]); |
| 164 | if (w_size < DEFLATE_MIN_SIZE || w_size > DEFLATE_MAX_SIZE) |
| 165 | return NULL; |
| 166 | |
| 167 | state = malloc(sizeof(struct deflate_state), M_DEVBUF, M_NOWAIT); |
| 168 | if (state == NULL) |
| 169 | return NULL; |
| 170 | |
| 171 | state->strm.next_in = NULL; |
| 172 | state->strm.zalloc = zalloc; |
| 173 | state->strm.zfree = zfree; |
| 174 | if (deflateInit2(&state->strm, Z_DEFAULT_COMPRESSION, DEFLATE_METHOD_VAL, |
| 175 | -w_size, 8, Z_DEFAULT_STRATEGY) != Z_OK) { |
| 176 | free(state, M_DEVBUF); |
| 177 | return NULL; |
| 178 | } |
| 179 | |
| 180 | state->w_size = w_size; |
| 181 | memset(&state->stats, 0, sizeof(state->stats)); |
| 182 | return (void *) state; |
| 183 | } |
| 184 | |
| 185 | static void |
| 186 | z_comp_free(void *arg) |
| 187 | { |
| 188 | struct deflate_state *state = (struct deflate_state *) arg; |
| 189 | |
| 190 | deflateEnd(&state->strm); |
| 191 | free(state, M_DEVBUF); |
| 192 | } |
| 193 | |
| 194 | static int |
| 195 | z_comp_init(void *arg, u_char *options, int opt_len, int unit, int hdrlen, |
| 196 | int debug) |
| 197 | { |
| 198 | struct deflate_state *state = (struct deflate_state *) arg; |
| 199 | |
| 200 | if (opt_len < CILEN_DEFLATE |
| 201 | || (options[0] != CI_DEFLATE && options[0] != CI_DEFLATE_DRAFT) |
| 202 | || options[1] != CILEN_DEFLATE |
| 203 | || DEFLATE_METHOD(options[2]) != DEFLATE_METHOD_VAL |
| 204 | || DEFLATE_SIZE(options[2]) != state->w_size |
| 205 | || options[3] != DEFLATE_CHK_SEQUENCE) |
| 206 | return 0; |
| 207 | |
| 208 | state->seqno = 0; |
| 209 | state->unit = unit; |
| 210 | state->hdrlen = hdrlen; |
| 211 | state->debug = debug; |
| 212 | |
| 213 | deflateReset(&state->strm); |
| 214 | |
| 215 | return 1; |
| 216 | } |
| 217 | |
| 218 | static void |
| 219 | z_comp_reset(void *arg) |
| 220 | { |
| 221 | struct deflate_state *state = (struct deflate_state *) arg; |
| 222 | |
| 223 | state->seqno = 0; |
| 224 | deflateReset(&state->strm); |
| 225 | } |
| 226 | |
| 227 | int |
| 228 | z_compress(void *arg, |
| 229 | struct mbuf **mret /* compressed packet (out) */, |
| 230 | struct mbuf *mp /* uncompressed packet (in) */, |
| 231 | int orig_len, int maxolen) |
| 232 | { |
| 233 | struct deflate_state *state = (struct deflate_state *) arg; |
| 234 | u_char *rptr, *wptr; |
| 235 | int proto, olen, wspace, r, flush; |
| 236 | struct mbuf *m; |
| 237 | |
| 238 | /* |
| 239 | * Check that the protocol is in the range we handle. |
| 240 | */ |
| 241 | rptr = mtod(mp, u_char *); |
| 242 | proto = PPP_PROTOCOL(rptr); |
| 243 | if (proto > 0x3fff || proto == 0xfd || proto == 0xfb) { |
| 244 | *mret = NULL; |
| 245 | return orig_len; |
| 246 | } |
| 247 | |
| 248 | /* Allocate one mbuf initially. */ |
| 249 | if (maxolen > orig_len) |
| 250 | maxolen = orig_len; |
| 251 | MGET(m, M_DONTWAIT, MT_DATA); |
| 252 | *mret = m; |
| 253 | if (m != NULL) { |
| 254 | m->m_len = 0; |
| 255 | if (maxolen + state->hdrlen > MLEN) |
| 256 | MCLGET(m, M_DONTWAIT); |
| 257 | wspace = M_TRAILINGSPACE(m); |
| 258 | if (state->hdrlen + PPP_HDRLEN + 2 < wspace) { |
| 259 | m->m_data += state->hdrlen; |
| 260 | wspace -= state->hdrlen; |
| 261 | } |
| 262 | wptr = mtod(m, u_char *); |
| 263 | |
| 264 | /* |
| 265 | * Copy over the PPP header and store the 2-byte sequence number. |
| 266 | */ |
| 267 | wptr[0] = PPP_ADDRESS(rptr); |
| 268 | wptr[1] = PPP_CONTROL(rptr); |
| 269 | wptr[2] = PPP_COMP >> 8; |
| 270 | wptr[3] = PPP_COMP; |
| 271 | wptr += PPP_HDRLEN; |
| 272 | wptr[0] = state->seqno >> 8; |
| 273 | wptr[1] = state->seqno; |
| 274 | wptr += 2; |
| 275 | state->strm.next_out = wptr; |
| 276 | state->strm.avail_out = wspace - (PPP_HDRLEN + 2); |
| 277 | } else { |
| 278 | state->strm.next_out = NULL; |
| 279 | state->strm.avail_out = 1000000; |
| 280 | wptr = NULL; |
| 281 | wspace = 0; |
| 282 | } |
| 283 | ++state->seqno; |
| 284 | |
| 285 | rptr += (proto > 0xff)? 2: 3; /* skip 1st proto byte if 0 */ |
| 286 | state->strm.next_in = rptr; |
| 287 | state->strm.avail_in = mtod(mp, u_char *) + mp->m_len - rptr; |
| 288 | mp = mp->m_next; |
| 289 | flush = (mp == NULL)? Z_PACKET_FLUSH: Z_NO_FLUSH; |
| 290 | olen = 0; |
| 291 | for (;;) { |
| 292 | r = deflate(&state->strm, flush); |
| 293 | if (r != Z_OK) { |
| 294 | printf("z_compress: deflate returned %d (%s)\n" , |
| 295 | r, (state->strm.msg? state->strm.msg: "" )); |
| 296 | break; |
| 297 | } |
| 298 | if (flush != Z_NO_FLUSH && state->strm.avail_out != 0) |
| 299 | break; /* all done */ |
| 300 | if (state->strm.avail_in == 0 && mp != NULL) { |
| 301 | state->strm.next_in = mtod(mp, u_char *); |
| 302 | state->strm.avail_in = mp->m_len; |
| 303 | mp = mp->m_next; |
| 304 | if (mp == NULL) |
| 305 | flush = Z_PACKET_FLUSH; |
| 306 | } |
| 307 | if (state->strm.avail_out == 0) { |
| 308 | if (m != NULL) { |
| 309 | m->m_len = wspace; |
| 310 | olen += wspace; |
| 311 | MGET(m->m_next, M_DONTWAIT, MT_DATA); |
| 312 | m = m->m_next; |
| 313 | if (m != NULL) { |
| 314 | m->m_len = 0; |
| 315 | if (maxolen - olen > MLEN) |
| 316 | MCLGET(m, M_DONTWAIT); |
| 317 | state->strm.next_out = mtod(m, u_char *); |
| 318 | state->strm.avail_out = wspace = M_TRAILINGSPACE(m); |
| 319 | } |
| 320 | } |
| 321 | if (m == NULL) { |
| 322 | state->strm.next_out = NULL; |
| 323 | state->strm.avail_out = 1000000; |
| 324 | } |
| 325 | } |
| 326 | } |
| 327 | if (m != NULL) |
| 328 | olen += (m->m_len = wspace - state->strm.avail_out); |
| 329 | |
| 330 | /* |
| 331 | * See if we managed to reduce the size of the packet. |
| 332 | */ |
| 333 | if (m != NULL && olen < orig_len) { |
| 334 | state->stats.comp_bytes += olen; |
| 335 | state->stats.comp_packets++; |
| 336 | } else { |
| 337 | if (*mret != NULL) { |
| 338 | m_freem(*mret); |
| 339 | *mret = NULL; |
| 340 | } |
| 341 | state->stats.inc_bytes += orig_len; |
| 342 | state->stats.inc_packets++; |
| 343 | olen = orig_len; |
| 344 | } |
| 345 | state->stats.unc_bytes += orig_len; |
| 346 | state->stats.unc_packets++; |
| 347 | |
| 348 | return olen; |
| 349 | } |
| 350 | |
| 351 | static void |
| 352 | z_comp_stats(void *arg, struct compstat *stats) |
| 353 | { |
| 354 | struct deflate_state *state = (struct deflate_state *) arg; |
| 355 | u_int out; |
| 356 | |
| 357 | *stats = state->stats; |
| 358 | stats->ratio = stats->unc_bytes; |
| 359 | out = stats->comp_bytes + stats->inc_bytes; |
| 360 | if (stats->ratio <= 0x7ffffff) |
| 361 | stats->ratio <<= 8; |
| 362 | else |
| 363 | out >>= 8; |
| 364 | if (out != 0) |
| 365 | stats->ratio /= out; |
| 366 | } |
| 367 | |
| 368 | /* |
| 369 | * Allocate space for a decompressor. |
| 370 | */ |
| 371 | static void * |
| 372 | z_decomp_alloc(u_char *options, int opt_len) |
| 373 | { |
| 374 | struct deflate_state *state; |
| 375 | int w_size; |
| 376 | |
| 377 | if (opt_len != CILEN_DEFLATE |
| 378 | || (options[0] != CI_DEFLATE && options[0] != CI_DEFLATE_DRAFT) |
| 379 | || options[1] != CILEN_DEFLATE |
| 380 | || DEFLATE_METHOD(options[2]) != DEFLATE_METHOD_VAL |
| 381 | || options[3] != DEFLATE_CHK_SEQUENCE) |
| 382 | return NULL; |
| 383 | w_size = DEFLATE_SIZE(options[2]); |
| 384 | if (w_size < DEFLATE_MIN_SIZE || w_size > DEFLATE_MAX_SIZE) |
| 385 | return NULL; |
| 386 | |
| 387 | state = malloc(sizeof(struct deflate_state), M_DEVBUF, M_NOWAIT); |
| 388 | if (state == NULL) |
| 389 | return NULL; |
| 390 | |
| 391 | state->strm.next_out = NULL; |
| 392 | state->strm.zalloc = zalloc; |
| 393 | state->strm.zfree = zfree; |
| 394 | if (inflateInit2(&state->strm, -w_size) != Z_OK) { |
| 395 | free(state, M_DEVBUF); |
| 396 | return NULL; |
| 397 | } |
| 398 | |
| 399 | state->w_size = w_size; |
| 400 | memset(&state->stats, 0, sizeof(state->stats)); |
| 401 | return (void *) state; |
| 402 | } |
| 403 | |
| 404 | static void |
| 405 | z_decomp_free(void *arg) |
| 406 | { |
| 407 | struct deflate_state *state = (struct deflate_state *) arg; |
| 408 | |
| 409 | inflateEnd(&state->strm); |
| 410 | free(state, M_DEVBUF); |
| 411 | } |
| 412 | |
| 413 | static int |
| 414 | z_decomp_init(void *arg, u_char *options, int opt_len, int unit, int hdrlen, |
| 415 | int mru, int debug) |
| 416 | { |
| 417 | struct deflate_state *state = (struct deflate_state *) arg; |
| 418 | |
| 419 | if (opt_len < CILEN_DEFLATE |
| 420 | || (options[0] != CI_DEFLATE && options[0] != CI_DEFLATE_DRAFT) |
| 421 | || options[1] != CILEN_DEFLATE |
| 422 | || DEFLATE_METHOD(options[2]) != DEFLATE_METHOD_VAL |
| 423 | || DEFLATE_SIZE(options[2]) != state->w_size |
| 424 | || options[3] != DEFLATE_CHK_SEQUENCE) |
| 425 | return 0; |
| 426 | |
| 427 | state->seqno = 0; |
| 428 | state->unit = unit; |
| 429 | state->hdrlen = hdrlen; |
| 430 | state->debug = debug; |
| 431 | state->mru = mru; |
| 432 | |
| 433 | inflateReset(&state->strm); |
| 434 | |
| 435 | return 1; |
| 436 | } |
| 437 | |
| 438 | static void |
| 439 | z_decomp_reset(void *arg) |
| 440 | { |
| 441 | struct deflate_state *state = (struct deflate_state *) arg; |
| 442 | |
| 443 | state->seqno = 0; |
| 444 | inflateReset(&state->strm); |
| 445 | } |
| 446 | |
| 447 | /* |
| 448 | * Decompress a Deflate-compressed packet. |
| 449 | * |
| 450 | * Because of patent problems, we return DECOMP_ERROR for errors |
| 451 | * found by inspecting the input data and for system problems, but |
| 452 | * DECOMP_FATALERROR for any errors which could possibly be said to |
| 453 | * be being detected "after" decompression. For DECOMP_ERROR, |
| 454 | * we can issue a CCP reset-request; for DECOMP_FATALERROR, we may be |
| 455 | * infringing a patent of Motorola's if we do, so we take CCP down |
| 456 | * instead. |
| 457 | * |
| 458 | * Given that the frame has the correct sequence number and a good FCS, |
| 459 | * errors such as invalid codes in the input most likely indicate a |
| 460 | * bug, so we return DECOMP_FATALERROR for them in order to turn off |
| 461 | * compression, even though they are detected by inspecting the input. |
| 462 | */ |
| 463 | int |
| 464 | z_decompress(void *arg, struct mbuf *mi, struct mbuf **mop) |
| 465 | { |
| 466 | struct deflate_state *state = (struct deflate_state *) arg; |
| 467 | struct mbuf *mo, *mo_head; |
| 468 | u_char *rptr, *wptr; |
| 469 | int rlen, olen, ospace; |
| 470 | int seq, i, flush, r, decode_proto; |
| 471 | u_char hdr[PPP_HDRLEN + DEFLATE_OVHD]; |
| 472 | |
| 473 | *mop = NULL; |
| 474 | rptr = mtod(mi, u_char *); |
| 475 | rlen = mi->m_len; |
| 476 | for (i = 0; i < PPP_HDRLEN + DEFLATE_OVHD; ++i) { |
| 477 | while (rlen <= 0) { |
| 478 | mi = mi->m_next; |
| 479 | if (mi == NULL) |
| 480 | return DECOMP_ERROR; |
| 481 | rptr = mtod(mi, u_char *); |
| 482 | rlen = mi->m_len; |
| 483 | } |
| 484 | hdr[i] = *rptr++; |
| 485 | --rlen; |
| 486 | } |
| 487 | |
| 488 | /* Check the sequence number. */ |
| 489 | seq = (hdr[PPP_HDRLEN] << 8) + hdr[PPP_HDRLEN+1]; |
| 490 | if (seq != state->seqno) { |
| 491 | if (state->debug) |
| 492 | printf("z_decompress%d: bad seq # %d, expected %d\n" , |
| 493 | state->unit, seq, state->seqno); |
| 494 | return DECOMP_ERROR; |
| 495 | } |
| 496 | ++state->seqno; |
| 497 | |
| 498 | /* Allocate an output mbuf. */ |
| 499 | MGETHDR(mo, M_DONTWAIT, MT_DATA); |
| 500 | if (mo == NULL) |
| 501 | return DECOMP_ERROR; |
| 502 | mo_head = mo; |
| 503 | mo->m_len = 0; |
| 504 | mo->m_next = NULL; |
| 505 | MCLGET(mo, M_DONTWAIT); |
| 506 | ospace = M_TRAILINGSPACE(mo); |
| 507 | if (state->hdrlen + PPP_HDRLEN < ospace) { |
| 508 | mo->m_data += state->hdrlen; |
| 509 | ospace -= state->hdrlen; |
| 510 | } |
| 511 | |
| 512 | /* |
| 513 | * Fill in the first part of the PPP header. The protocol field |
| 514 | * comes from the decompressed data. |
| 515 | */ |
| 516 | wptr = mtod(mo, u_char *); |
| 517 | wptr[0] = PPP_ADDRESS(hdr); |
| 518 | wptr[1] = PPP_CONTROL(hdr); |
| 519 | wptr[2] = 0; |
| 520 | |
| 521 | /* |
| 522 | * Set up to call inflate. We set avail_out to 1 initially so we can |
| 523 | * look at the first byte of the output and decide whether we have |
| 524 | * a 1-byte or 2-byte protocol field. |
| 525 | */ |
| 526 | state->strm.next_in = rptr; |
| 527 | state->strm.avail_in = rlen; |
| 528 | mi = mi->m_next; |
| 529 | flush = (mi == NULL)? Z_PACKET_FLUSH: Z_NO_FLUSH; |
| 530 | rlen += PPP_HDRLEN + DEFLATE_OVHD; |
| 531 | state->strm.next_out = wptr + 3; |
| 532 | state->strm.avail_out = 1; |
| 533 | decode_proto = 1; |
| 534 | olen = 0; |
| 535 | |
| 536 | /* |
| 537 | * Call inflate, supplying more input or output as needed. |
| 538 | */ |
| 539 | for (;;) { |
| 540 | r = inflate(&state->strm, flush); |
| 541 | if (r != Z_OK) { |
| 542 | #if !DEFLATE_DEBUG |
| 543 | if (state->debug) |
| 544 | #endif |
| 545 | printf("z_decompress%d: inflate returned %d (%s)\n" , |
| 546 | state->unit, r, (state->strm.msg? state->strm.msg: "" )); |
| 547 | m_freem(mo_head); |
| 548 | return DECOMP_FATALERROR; |
| 549 | } |
| 550 | if (flush != Z_NO_FLUSH && state->strm.avail_out != 0) |
| 551 | break; /* all done */ |
| 552 | if (state->strm.avail_in == 0 && mi != NULL) { |
| 553 | state->strm.next_in = mtod(mi, u_char *); |
| 554 | state->strm.avail_in = mi->m_len; |
| 555 | rlen += mi->m_len; |
| 556 | mi = mi->m_next; |
| 557 | if (mi == NULL) |
| 558 | flush = Z_PACKET_FLUSH; |
| 559 | } |
| 560 | if (state->strm.avail_out == 0) { |
| 561 | if (decode_proto) { |
| 562 | state->strm.avail_out = ospace - PPP_HDRLEN; |
| 563 | if ((wptr[3] & 1) == 0) { |
| 564 | /* 2-byte protocol field */ |
| 565 | wptr[2] = wptr[3]; |
| 566 | --state->strm.next_out; |
| 567 | ++state->strm.avail_out; |
| 568 | --olen; |
| 569 | } |
| 570 | decode_proto = 0; |
| 571 | } else { |
| 572 | mo->m_len = ospace; |
| 573 | olen += ospace; |
| 574 | MGET(mo->m_next, M_DONTWAIT, MT_DATA); |
| 575 | mo = mo->m_next; |
| 576 | if (mo == NULL) { |
| 577 | m_freem(mo_head); |
| 578 | return DECOMP_ERROR; |
| 579 | } |
| 580 | MCLGET(mo, M_DONTWAIT); |
| 581 | state->strm.next_out = mtod(mo, u_char *); |
| 582 | state->strm.avail_out = ospace = M_TRAILINGSPACE(mo); |
| 583 | } |
| 584 | } |
| 585 | } |
| 586 | if (decode_proto) { |
| 587 | m_freem(mo_head); |
| 588 | return DECOMP_ERROR; |
| 589 | } |
| 590 | olen += (mo->m_len = ospace - state->strm.avail_out); |
| 591 | #if DEFLATE_DEBUG |
| 592 | if (olen > state->mru + PPP_HDRLEN) |
| 593 | printf("ppp_deflate%d: exceeded mru (%d > %d)\n" , |
| 594 | state->unit, olen, state->mru + PPP_HDRLEN); |
| 595 | #endif |
| 596 | |
| 597 | state->stats.unc_bytes += olen; |
| 598 | state->stats.unc_packets++; |
| 599 | state->stats.comp_bytes += rlen; |
| 600 | state->stats.comp_packets++; |
| 601 | |
| 602 | *mop = mo_head; |
| 603 | return DECOMP_OK; |
| 604 | } |
| 605 | |
| 606 | /* |
| 607 | * Incompressible data has arrived - add it to the history. |
| 608 | */ |
| 609 | static void |
| 610 | z_incomp(void *arg, struct mbuf *mi) |
| 611 | { |
| 612 | struct deflate_state *state = (struct deflate_state *) arg; |
| 613 | u_char *rptr; |
| 614 | int rlen, proto, r; |
| 615 | |
| 616 | /* |
| 617 | * Check that the protocol is one we handle. |
| 618 | */ |
| 619 | rptr = mtod(mi, u_char *); |
| 620 | proto = PPP_PROTOCOL(rptr); |
| 621 | if (proto > 0x3fff || proto == 0xfd || proto == 0xfb) |
| 622 | return; |
| 623 | |
| 624 | ++state->seqno; |
| 625 | |
| 626 | /* |
| 627 | * Iterate through the mbufs, adding the characters in them |
| 628 | * to the decompressor's history. For the first mbuf, we start |
| 629 | * at the either the 1st or 2nd byte of the protocol field, |
| 630 | * depending on whether the protocol value is compressible. |
| 631 | */ |
| 632 | rlen = mi->m_len; |
| 633 | state->strm.next_in = rptr + 3; |
| 634 | state->strm.avail_in = rlen - 3; |
| 635 | if (proto > 0xff) { |
| 636 | --state->strm.next_in; |
| 637 | ++state->strm.avail_in; |
| 638 | } |
| 639 | for (;;) { |
| 640 | r = inflateIncomp(&state->strm); |
| 641 | if (r != Z_OK) { |
| 642 | /* gak! */ |
| 643 | #if !DEFLATE_DEBUG |
| 644 | if (state->debug) |
| 645 | #endif |
| 646 | printf("z_incomp%d: inflateIncomp returned %d (%s)\n" , |
| 647 | state->unit, r, (state->strm.msg? state->strm.msg: "" )); |
| 648 | return; |
| 649 | } |
| 650 | mi = mi->m_next; |
| 651 | if (mi == NULL) |
| 652 | break; |
| 653 | state->strm.next_in = mtod(mi, u_char *); |
| 654 | state->strm.avail_in = mi->m_len; |
| 655 | rlen += mi->m_len; |
| 656 | } |
| 657 | |
| 658 | /* |
| 659 | * Update stats. |
| 660 | */ |
| 661 | state->stats.inc_bytes += rlen; |
| 662 | state->stats.inc_packets++; |
| 663 | state->stats.unc_bytes += rlen; |
| 664 | state->stats.unc_packets++; |
| 665 | } |
| 666 | |
| 667 | MODULE(MODULE_CLASS_MISC, ppp_deflate, "zlib,if_ppp" ); |
| 668 | |
| 669 | static int |
| 670 | ppp_deflate_modcmd(modcmd_t cmd, void *arg) |
| 671 | { |
| 672 | |
| 673 | switch (cmd) { |
| 674 | case MODULE_CMD_INIT: |
| 675 | return ppp_register_compressor(ppp_deflate, 2); |
| 676 | case MODULE_CMD_FINI: |
| 677 | return ppp_unregister_compressor(ppp_deflate, 2); |
| 678 | case MODULE_CMD_STAT: |
| 679 | return 0; |
| 680 | default: |
| 681 | return ENOTTY; |
| 682 | } |
| 683 | |
| 684 | return ENOTTY; |
| 685 | } |
| 686 | #endif /* DO_DEFLATE */ |
| 687 | |