ccp.c revision 1.2
1/* $OpenBSD: ccp.c,v 1.2 1996/03/25 15:55:32 niklas Exp $ */ 2 3/* 4 * ccp.c - PPP Compression Control Protocol. 5 * 6 * Copyright (c) 1994 The Australian National University. 7 * All rights reserved. 8 * 9 * Permission to use, copy, modify, and distribute this software and its 10 * documentation is hereby granted, provided that the above copyright 11 * notice appears in all copies. This software is provided without any 12 * warranty, express or implied. The Australian National University 13 * makes no representations about the suitability of this software for 14 * any purpose. 15 * 16 * IN NO EVENT SHALL THE AUSTRALIAN NATIONAL UNIVERSITY BE LIABLE TO ANY 17 * PARTY FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES 18 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF 19 * THE AUSTRALIAN NATIONAL UNIVERSITY HAVE BEEN ADVISED OF THE POSSIBILITY 20 * OF SUCH DAMAGE. 21 * 22 * THE AUSTRALIAN NATIONAL UNIVERSITY SPECIFICALLY DISCLAIMS ANY WARRANTIES, 23 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY 24 * AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS 25 * ON AN "AS IS" BASIS, AND THE AUSTRALIAN NATIONAL UNIVERSITY HAS NO 26 * OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, 27 * OR MODIFICATIONS. 28 */ 29 30#ifndef lint 31static char rcsid[] = "$OpenBSD: ccp.c,v 1.2 1996/03/25 15:55:32 niklas Exp $"; 32#endif 33 34#include <string.h> 35#include <syslog.h> 36#include <sys/ioctl.h> 37#include <net/ppp-comp.h> 38 39#include "pppd.h" 40#include "fsm.h" 41#include "ccp.h" 42 43struct protent ccp_protent = { 44 PPP_CCP, ccp_init, ccp_input, ccp_protrej, 45 ccp_lowerup, ccp_lowerdown, ccp_open, ccp_close, 46 ccp_printpkt, ccp_datainput, 1, "CCP", NULL, NULL 47}; 48 49fsm ccp_fsm[NUM_PPP]; 50ccp_options ccp_wantoptions[NUM_PPP]; /* what to request the peer to use */ 51ccp_options ccp_gotoptions[NUM_PPP]; /* what the peer agreed to do */ 52ccp_options ccp_allowoptions[NUM_PPP]; /* what we'll agree to do */ 53ccp_options ccp_hisoptions[NUM_PPP]; /* what we agreed to do */ 54 55/* 56 * Callbacks for fsm code. 57 */ 58static void ccp_resetci __P((fsm *)); 59static int ccp_cilen __P((fsm *)); 60static void ccp_addci __P((fsm *, u_char *, int *)); 61static int ccp_ackci __P((fsm *, u_char *, int)); 62static int ccp_nakci __P((fsm *, u_char *, int)); 63static int ccp_rejci __P((fsm *, u_char *, int)); 64static int ccp_reqci __P((fsm *, u_char *, int *, int)); 65static void ccp_up __P((fsm *)); 66static void ccp_down __P((fsm *)); 67static int ccp_extcode __P((fsm *, int, int, u_char *, int)); 68static void ccp_rack_timeout __P(()); 69 70static fsm_callbacks ccp_callbacks = { 71 ccp_resetci, 72 ccp_cilen, 73 ccp_addci, 74 ccp_ackci, 75 ccp_nakci, 76 ccp_rejci, 77 ccp_reqci, 78 ccp_up, 79 ccp_down, 80 NULL, 81 NULL, 82 NULL, 83 NULL, 84 ccp_extcode, 85 "CCP" 86}; 87 88/* 89 * Do we want / did we get any compression? 90 */ 91#define ANY_COMPRESS(opt) ((opt).deflate || (opt).bsd_compress \ 92 || (opt).predictor_1 || (opt).predictor_2) 93 94/* 95 * Local state (mainly for handling reset-reqs and reset-acks). 96 */ 97static int ccp_localstate[NUM_PPP]; 98#define RACK_PENDING 1 /* waiting for reset-ack */ 99#define RREQ_REPEAT 2 /* send another reset-req if no reset-ack */ 100 101#define RACKTIMEOUT 1 /* second */ 102 103static int all_rejected[NUM_PPP]; /* we rejected all peer's options */ 104 105/* 106 * ccp_init - initialize CCP. 107 */ 108void 109ccp_init(unit) 110 int unit; 111{ 112 fsm *f = &ccp_fsm[unit]; 113 114 f->unit = unit; 115 f->protocol = PPP_CCP; 116 f->callbacks = &ccp_callbacks; 117 fsm_init(f); 118 119 memset(&ccp_wantoptions[unit], 0, sizeof(ccp_options)); 120 memset(&ccp_gotoptions[unit], 0, sizeof(ccp_options)); 121 memset(&ccp_allowoptions[unit], 0, sizeof(ccp_options)); 122 memset(&ccp_hisoptions[unit], 0, sizeof(ccp_options)); 123 124 ccp_wantoptions[0].deflate = 1; 125 ccp_wantoptions[0].deflate_size = DEFLATE_MAX_SIZE; 126 ccp_allowoptions[0].deflate = 1; 127 ccp_allowoptions[0].deflate_size = DEFLATE_MAX_SIZE; 128 129 ccp_wantoptions[0].bsd_compress = 1; 130 ccp_wantoptions[0].bsd_bits = BSD_MAX_BITS; 131 ccp_allowoptions[0].bsd_compress = 1; 132 ccp_allowoptions[0].bsd_bits = BSD_MAX_BITS; 133 134 ccp_allowoptions[0].predictor_1 = 1; 135} 136 137/* 138 * ccp_open - CCP is allowed to come up. 139 */ 140void 141ccp_open(unit) 142 int unit; 143{ 144 fsm *f = &ccp_fsm[unit]; 145 146 if (f->state != OPENED) 147 ccp_flags_set(unit, 1, 0); 148 if (!ANY_COMPRESS(ccp_wantoptions[unit])) 149 f->flags |= OPT_SILENT; 150 fsm_open(f); 151} 152 153/* 154 * ccp_close - Terminate CCP. 155 */ 156void 157ccp_close(unit, reason) 158 int unit; 159 char *reason; 160{ 161 ccp_flags_set(unit, 0, 0); 162 fsm_close(&ccp_fsm[unit], reason); 163} 164 165/* 166 * ccp_lowerup - we may now transmit CCP packets. 167 */ 168void 169ccp_lowerup(unit) 170 int unit; 171{ 172 fsm_lowerup(&ccp_fsm[unit]); 173} 174 175/* 176 * ccp_lowerdown - we may not transmit CCP packets. 177 */ 178void 179ccp_lowerdown(unit) 180 int unit; 181{ 182 fsm_lowerdown(&ccp_fsm[unit]); 183} 184 185/* 186 * ccp_input - process a received CCP packet. 187 */ 188void 189ccp_input(unit, p, len) 190 int unit; 191 u_char *p; 192 int len; 193{ 194 fsm *f = &ccp_fsm[unit]; 195 int oldstate; 196 197 /* 198 * Check for a terminate-request so we can print a message. 199 */ 200 oldstate = f->state; 201 fsm_input(f, p, len); 202 if (oldstate == OPENED && p[0] == TERMREQ && f->state != OPENED) 203 syslog(LOG_NOTICE, "Compression disabled by peer."); 204 205 /* 206 * If we get a terminate-ack and we're not asking for compression, 207 * close CCP. 208 */ 209 if (oldstate == REQSENT && p[0] == TERMACK 210 && !ANY_COMPRESS(ccp_gotoptions[unit])) 211 ccp_close(unit, "No compression negotiated"); 212} 213 214/* 215 * Handle a CCP-specific code. 216 */ 217static int 218ccp_extcode(f, code, id, p, len) 219 fsm *f; 220 int code, id; 221 u_char *p; 222 int len; 223{ 224 switch (code) { 225 case CCP_RESETREQ: 226 if (f->state != OPENED) 227 break; 228 /* send a reset-ack, which the transmitter will see and 229 reset its compression state. */ 230 fsm_sdata(f, CCP_RESETACK, id, NULL, 0); 231 break; 232 233 case CCP_RESETACK: 234 if (ccp_localstate[f->unit] & RACK_PENDING && id == f->reqid) { 235 ccp_localstate[f->unit] &= ~(RACK_PENDING | RREQ_REPEAT); 236 UNTIMEOUT(ccp_rack_timeout, (caddr_t) f); 237 } 238 break; 239 240 default: 241 return 0; 242 } 243 244 return 1; 245} 246 247/* 248 * ccp_protrej - peer doesn't talk CCP. 249 */ 250void 251ccp_protrej(unit) 252 int unit; 253{ 254 ccp_flags_set(unit, 0, 0); 255 fsm_lowerdown(&ccp_fsm[unit]); 256} 257 258/* 259 * ccp_resetci - initialize at start of negotiation. 260 */ 261static void 262ccp_resetci(f) 263 fsm *f; 264{ 265 ccp_options *go = &ccp_gotoptions[f->unit]; 266 u_char opt_buf[16]; 267 268 *go = ccp_wantoptions[f->unit]; 269 all_rejected[f->unit] = 0; 270 271 /* 272 * Check whether the kernel knows about the various 273 * compression methods we might request. 274 */ 275 if (go->bsd_compress) { 276 opt_buf[0] = CI_BSD_COMPRESS; 277 opt_buf[1] = CILEN_BSD_COMPRESS; 278 opt_buf[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, BSD_MIN_BITS); 279 if (ccp_test(f->unit, opt_buf, CILEN_BSD_COMPRESS, 0) <= 0) 280 go->bsd_compress = 0; 281 } 282 if (go->deflate) { 283 opt_buf[0] = CI_DEFLATE; 284 opt_buf[1] = CILEN_DEFLATE; 285 opt_buf[2] = DEFLATE_MAKE_OPT(DEFLATE_MIN_SIZE); 286 opt_buf[3] = DEFLATE_CHK_SEQUENCE; 287 if (ccp_test(f->unit, opt_buf, CILEN_DEFLATE, 0) <= 0) 288 go->deflate = 0; 289 } 290 if (go->predictor_1) { 291 opt_buf[0] = CI_PREDICTOR_1; 292 opt_buf[1] = CILEN_PREDICTOR_1; 293 if (ccp_test(f->unit, opt_buf, CILEN_PREDICTOR_1, 0) <= 0) 294 go->predictor_1 = 0; 295 } 296 if (go->predictor_2) { 297 opt_buf[0] = CI_PREDICTOR_2; 298 opt_buf[1] = CILEN_PREDICTOR_2; 299 if (ccp_test(f->unit, opt_buf, CILEN_PREDICTOR_2, 0) <= 0) 300 go->predictor_2 = 0; 301 } 302} 303 304/* 305 * ccp_cilen - Return total length of our configuration info. 306 */ 307static int 308ccp_cilen(f) 309 fsm *f; 310{ 311 ccp_options *go = &ccp_gotoptions[f->unit]; 312 313 return (go->bsd_compress? CILEN_BSD_COMPRESS: 0) 314 + (go->deflate? CILEN_DEFLATE: 0) 315 + (go->predictor_1? CILEN_PREDICTOR_1: 0) 316 + (go->predictor_2? CILEN_PREDICTOR_2: 0); 317} 318 319/* 320 * ccp_addci - put our requests in a packet. 321 */ 322static void 323ccp_addci(f, p, lenp) 324 fsm *f; 325 u_char *p; 326 int *lenp; 327{ 328 int res; 329 ccp_options *go = &ccp_gotoptions[f->unit]; 330 u_char *p0 = p; 331 332 /* 333 * Add the compression types that we can receive, in decreasing 334 * preference order. Get the kernel to allocate the first one 335 * in case it gets Acked. 336 */ 337 if (go->deflate) { 338 p[0] = CI_DEFLATE; 339 p[1] = CILEN_DEFLATE; 340 p[2] = DEFLATE_MAKE_OPT(go->deflate_size); 341 p[3] = DEFLATE_CHK_SEQUENCE; 342 for (;;) { 343 res = ccp_test(f->unit, p, CILEN_DEFLATE, 0); 344 if (res > 0) { 345 p += CILEN_DEFLATE; 346 break; 347 } 348 if (res < 0 || go->deflate_size <= DEFLATE_MIN_SIZE) { 349 go->deflate = 0; 350 break; 351 } 352 --go->deflate_size; 353 p[2] = DEFLATE_MAKE_OPT(go->deflate_size); 354 } 355 } 356 if (go->bsd_compress) { 357 p[0] = CI_BSD_COMPRESS; 358 p[1] = CILEN_BSD_COMPRESS; 359 p[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, go->bsd_bits); 360 if (p != p0) { 361 p += CILEN_BSD_COMPRESS; /* not the first option */ 362 } else { 363 for (;;) { 364 res = ccp_test(f->unit, p, CILEN_BSD_COMPRESS, 0); 365 if (res > 0) { 366 p += CILEN_BSD_COMPRESS; 367 break; 368 } 369 if (res < 0 || go->bsd_bits <= BSD_MIN_BITS) { 370 go->bsd_compress = 0; 371 break; 372 } 373 --go->bsd_bits; 374 p[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, go->bsd_bits); 375 } 376 } 377 } 378 /* XXX Should Predictor 2 be preferable to Predictor 1? */ 379 if (go->predictor_1) { 380 p[0] = CI_PREDICTOR_1; 381 p[1] = CILEN_PREDICTOR_1; 382 if (p == p0 && ccp_test(f->unit, p, CILEN_PREDICTOR_1, 0) <= 0) { 383 go->predictor_1 = 0; 384 } else { 385 p += CILEN_PREDICTOR_1; 386 } 387 } 388 if (go->predictor_2) { 389 p[0] = CI_PREDICTOR_2; 390 p[1] = CILEN_PREDICTOR_2; 391 if (p == p0 && ccp_test(f->unit, p, CILEN_PREDICTOR_2, 0) <= 0) { 392 go->predictor_2 = 0; 393 } else { 394 p += CILEN_PREDICTOR_2; 395 } 396 } 397 398 *lenp = p - p0; 399} 400 401/* 402 * ccp_ackci - process a received configure-ack, and return 403 * 1 iff the packet was OK. 404 */ 405static int 406ccp_ackci(f, p, len) 407 fsm *f; 408 u_char *p; 409 int len; 410{ 411 ccp_options *go = &ccp_gotoptions[f->unit]; 412 u_char *p0 = p; 413 414 if (go->deflate) { 415 if (len < CILEN_DEFLATE 416 || p[0] != CI_DEFLATE || p[1] != CILEN_DEFLATE 417 || p[2] != DEFLATE_MAKE_OPT(go->deflate_size) 418 || p[3] != DEFLATE_CHK_SEQUENCE) 419 return 0; 420 p += CILEN_DEFLATE; 421 len -= CILEN_DEFLATE; 422 /* XXX Cope with first/fast ack */ 423 if (len == 0) 424 return 1; 425 } 426 if (go->bsd_compress) { 427 if (len < CILEN_BSD_COMPRESS 428 || p[0] != CI_BSD_COMPRESS || p[1] != CILEN_BSD_COMPRESS 429 || p[2] != BSD_MAKE_OPT(BSD_CURRENT_VERSION, go->bsd_bits)) 430 return 0; 431 p += CILEN_BSD_COMPRESS; 432 len -= CILEN_BSD_COMPRESS; 433 /* XXX Cope with first/fast ack */ 434 if (p == p0 && len == 0) 435 return 1; 436 } 437 if (go->predictor_1) { 438 if (len < CILEN_PREDICTOR_1 439 || p[0] != CI_PREDICTOR_1 || p[1] != CILEN_PREDICTOR_1) 440 return 0; 441 p += CILEN_PREDICTOR_1; 442 len -= CILEN_PREDICTOR_1; 443 /* XXX Cope with first/fast ack */ 444 if (p == p0 && len == 0) 445 return 1; 446 } 447 if (go->predictor_2) { 448 if (len < CILEN_PREDICTOR_2 449 || p[0] != CI_PREDICTOR_2 || p[1] != CILEN_PREDICTOR_2) 450 return 0; 451 p += CILEN_PREDICTOR_2; 452 len -= CILEN_PREDICTOR_2; 453 /* XXX Cope with first/fast ack */ 454 if (p == p0 && len == 0) 455 return 1; 456 } 457 458 if (len != 0) 459 return 0; 460 return 1; 461} 462 463/* 464 * ccp_nakci - process received configure-nak. 465 * Returns 1 iff the nak was OK. 466 */ 467static int 468ccp_nakci(f, p, len) 469 fsm *f; 470 u_char *p; 471 int len; 472{ 473 ccp_options *go = &ccp_gotoptions[f->unit]; 474 ccp_options no; /* options we've seen already */ 475 ccp_options try; /* options to ask for next time */ 476 477 memset(&no, 0, sizeof(no)); 478 try = *go; 479 480 if (go->deflate && len >= CILEN_DEFLATE 481 && p[0] == CI_DEFLATE && p[1] == CILEN_DEFLATE) { 482 no.deflate = 1; 483 /* 484 * Peer wants us to use a different code size or something. 485 * Stop asking for Deflate if we don't understand his suggestion. 486 */ 487 if (DEFLATE_METHOD(p[2]) != DEFLATE_METHOD_VAL 488 || DEFLATE_SIZE(p[2]) < DEFLATE_MIN_SIZE 489 || p[3] != DEFLATE_CHK_SEQUENCE) 490 try.deflate = 0; 491 else if (DEFLATE_SIZE(p[2]) < go->deflate_size) 492 go->deflate_size = DEFLATE_SIZE(p[2]); 493 p += CILEN_DEFLATE; 494 len -= CILEN_DEFLATE; 495 } 496 497 if (go->bsd_compress && len >= CILEN_BSD_COMPRESS 498 && p[0] == CI_BSD_COMPRESS && p[1] == CILEN_BSD_COMPRESS) { 499 no.bsd_compress = 1; 500 /* 501 * Peer wants us to use a different number of bits 502 * or a different version. 503 */ 504 if (BSD_VERSION(p[2]) != BSD_CURRENT_VERSION) 505 try.bsd_compress = 0; 506 else if (BSD_NBITS(p[2]) < go->bsd_bits) 507 try.bsd_bits = BSD_NBITS(p[2]); 508 p += CILEN_BSD_COMPRESS; 509 len -= CILEN_BSD_COMPRESS; 510 } 511 512 /* 513 * Predictor-1 and 2 have no options, so they can't be Naked. 514 * 515 * XXX What should we do with any remaining options? 516 */ 517 518 if (len != 0) 519 return 0; 520 521 if (f->state != OPENED) 522 *go = try; 523 return 1; 524} 525 526/* 527 * ccp_rejci - reject some of our suggested compression methods. 528 */ 529static int 530ccp_rejci(f, p, len) 531 fsm *f; 532 u_char *p; 533 int len; 534{ 535 ccp_options *go = &ccp_gotoptions[f->unit]; 536 ccp_options try; /* options to request next time */ 537 538 try = *go; 539 540 /* 541 * Cope with empty configure-rejects by ceasing to send 542 * configure-requests. 543 */ 544 if (len == 0 && all_rejected[f->unit]) 545 return -1; 546 547 if (go->deflate && len >= CILEN_DEFLATE 548 && p[0] == CI_DEFLATE && p[1] == CILEN_DEFLATE) { 549 if (p[2] != DEFLATE_MAKE_OPT(go->deflate_size) 550 || p[3] != DEFLATE_CHK_SEQUENCE) 551 return 0; /* Rej is bad */ 552 try.deflate = 0; 553 p += CILEN_DEFLATE; 554 len -= CILEN_DEFLATE; 555 } 556 if (go->bsd_compress && len >= CILEN_BSD_COMPRESS 557 && p[0] == CI_BSD_COMPRESS && p[1] == CILEN_BSD_COMPRESS) { 558 if (p[2] != BSD_MAKE_OPT(BSD_CURRENT_VERSION, go->bsd_bits)) 559 return 0; 560 try.bsd_compress = 0; 561 p += CILEN_BSD_COMPRESS; 562 len -= CILEN_BSD_COMPRESS; 563 } 564 if (go->predictor_1 && len >= CILEN_PREDICTOR_1 565 && p[0] == CI_PREDICTOR_1 && p[1] == CILEN_PREDICTOR_1) { 566 try.predictor_1 = 0; 567 p += CILEN_PREDICTOR_1; 568 len -= CILEN_PREDICTOR_1; 569 } 570 if (go->predictor_2 && len >= CILEN_PREDICTOR_2 571 && p[0] == CI_PREDICTOR_2 && p[1] == CILEN_PREDICTOR_2) { 572 try.predictor_2 = 0; 573 p += CILEN_PREDICTOR_2; 574 len -= CILEN_PREDICTOR_2; 575 } 576 577 if (len != 0) 578 return 0; 579 580 if (f->state != OPENED) 581 *go = try; 582 583 return 1; 584} 585 586/* 587 * ccp_reqci - processed a received configure-request. 588 * Returns CONFACK, CONFNAK or CONFREJ and the packet modified 589 * appropriately. 590 */ 591static int 592ccp_reqci(f, p, lenp, dont_nak) 593 fsm *f; 594 u_char *p; 595 int *lenp; 596 int dont_nak; 597{ 598 int ret, newret, res; 599 u_char *p0, *retp; 600 int len, clen, type, nb; 601 ccp_options *ho = &ccp_hisoptions[f->unit]; 602 ccp_options *ao = &ccp_allowoptions[f->unit]; 603 604 ret = CONFACK; 605 retp = p0 = p; 606 len = *lenp; 607 608 memset(ho, 0, sizeof(ccp_options)); 609 610 while (len > 0) { 611 newret = CONFACK; 612 if (len < 2 || p[1] < 2 || p[1] > len) { 613 /* length is bad */ 614 clen = len; 615 newret = CONFREJ; 616 617 } else { 618 type = p[0]; 619 clen = p[1]; 620 621 switch (type) { 622 case CI_DEFLATE: 623 if (!ao->deflate || clen != CILEN_DEFLATE) { 624 newret = CONFREJ; 625 break; 626 } 627 628 ho->deflate = 1; 629 ho->deflate_size = nb = DEFLATE_SIZE(p[2]); 630 if (DEFLATE_METHOD(p[2]) != DEFLATE_METHOD_VAL 631 || p[3] != DEFLATE_CHK_SEQUENCE 632 || nb > ao->deflate_size || nb < DEFLATE_MIN_SIZE) { 633 newret = CONFNAK; 634 if (!dont_nak) { 635 p[2] = DEFLATE_MAKE_OPT(ao->deflate_size); 636 p[3] = DEFLATE_CHK_SEQUENCE; 637 } 638 break; 639 } 640 641 /* 642 * Check whether we can do Deflate with the window 643 * size they want. If the window is too big, reduce 644 * it until the kernel can cope and nak with that. 645 * We only check this for the first option. 646 */ 647 if (p == p0) { 648 for (;;) { 649 res = ccp_test(f->unit, p, CILEN_DEFLATE, 1); 650 if (res > 0) 651 break; /* it's OK now */ 652 if (res < 0 || nb == DEFLATE_MIN_SIZE || dont_nak) { 653 newret = CONFREJ; 654 p[2] = DEFLATE_MAKE_OPT(ho->deflate_size); 655 break; 656 } 657 newret = CONFNAK; 658 --nb; 659 p[2] = DEFLATE_MAKE_OPT(nb); 660 } 661 } 662 break; 663 664 case CI_BSD_COMPRESS: 665 if (!ao->bsd_compress || clen != CILEN_BSD_COMPRESS) { 666 newret = CONFREJ; 667 break; 668 } 669 670 ho->bsd_compress = 1; 671 ho->bsd_bits = nb = BSD_NBITS(p[2]); 672 if (BSD_VERSION(p[2]) != BSD_CURRENT_VERSION 673 || nb > ao->bsd_bits || nb < BSD_MIN_BITS) { 674 newret = CONFNAK; 675 if (!dont_nak) 676 p[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, ao->bsd_bits); 677 break; 678 } 679 680 /* 681 * Check whether we can do BSD-Compress with the code 682 * size they want. If the code size is too big, reduce 683 * it until the kernel can cope and nak with that. 684 * We only check this for the first option. 685 */ 686 if (p == p0) { 687 for (;;) { 688 res = ccp_test(f->unit, p, CILEN_BSD_COMPRESS, 1); 689 if (res > 0) 690 break; 691 if (res < 0 || nb == BSD_MIN_BITS || dont_nak) { 692 newret = CONFREJ; 693 p[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, 694 ho->bsd_bits); 695 break; 696 } 697 newret = CONFNAK; 698 --nb; 699 p[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, nb); 700 } 701 } 702 break; 703 704 case CI_PREDICTOR_1: 705 if (!ao->predictor_1 || clen != CILEN_PREDICTOR_1) { 706 newret = CONFREJ; 707 break; 708 } 709 710 ho->predictor_1 = 1; 711 if (p == p0 712 && ccp_test(f->unit, p, CILEN_PREDICTOR_1, 1) <= 0) { 713 newret = CONFREJ; 714 } 715 break; 716 717 case CI_PREDICTOR_2: 718 if (!ao->predictor_2 || clen != CILEN_PREDICTOR_2) { 719 newret = CONFREJ; 720 break; 721 } 722 723 ho->predictor_2 = 1; 724 if (p == p0 725 && ccp_test(f->unit, p, CILEN_PREDICTOR_2, 1) <= 0) { 726 newret = CONFREJ; 727 } 728 break; 729 730 default: 731 newret = CONFREJ; 732 } 733 } 734 735 if (newret == CONFNAK && dont_nak) 736 newret = CONFREJ; 737 if (!(newret == CONFACK || newret == CONFNAK && ret == CONFREJ)) { 738 /* we're returning this option */ 739 if (newret == CONFREJ && ret == CONFNAK) 740 retp = p0; 741 ret = newret; 742 if (p != retp) 743 BCOPY(p, retp, clen); 744 retp += clen; 745 } 746 747 p += clen; 748 len -= clen; 749 } 750 751 if (ret != CONFACK) { 752 if (ret == CONFREJ && *lenp == retp - p0) 753 all_rejected[f->unit] = 1; 754 else 755 *lenp = retp - p0; 756 } 757 return ret; 758} 759 760/* 761 * CCP has come up - inform the kernel driver. 762 */ 763static void 764ccp_up(f) 765 fsm *f; 766{ 767 ccp_options *go = &ccp_gotoptions[f->unit]; 768 ccp_options *ho = &ccp_hisoptions[f->unit]; 769 770 ccp_flags_set(f->unit, 1, 1); 771 if (ANY_COMPRESS(*go) || ANY_COMPRESS(*ho)) 772 syslog(LOG_NOTICE, "%s enabled", 773 ANY_COMPRESS(*go)? ANY_COMPRESS(*ho)? "Compression": 774 "Receive compression": "Transmit compression"); 775} 776 777/* 778 * CCP has gone down - inform the kernel driver. 779 */ 780static void 781ccp_down(f) 782 fsm *f; 783{ 784 if (ccp_localstate[f->unit] & RACK_PENDING) 785 UNTIMEOUT(ccp_rack_timeout, (caddr_t) f); 786 ccp_localstate[f->unit] = 0; 787 ccp_flags_set(f->unit, 1, 0); 788} 789 790/* 791 * Print the contents of a CCP packet. 792 */ 793char *ccp_codenames[] = { 794 "ConfReq", "ConfAck", "ConfNak", "ConfRej", 795 "TermReq", "TermAck", "CodeRej", 796 NULL, NULL, NULL, NULL, NULL, NULL, 797 "ResetReq", "ResetAck", 798}; 799 800int 801ccp_printpkt(p, plen, printer, arg) 802 u_char *p; 803 int plen; 804 void (*printer) __P((void *, char *, ...)); 805 void *arg; 806{ 807 u_char *p0, *optend; 808 int code, id, len; 809 int optlen; 810 811 p0 = p; 812 if (plen < HEADERLEN) 813 return 0; 814 code = p[0]; 815 id = p[1]; 816 len = (p[2] << 8) + p[3]; 817 if (len < HEADERLEN || len > plen) 818 return 0; 819 820 if (code >= 1 && code <= sizeof(ccp_codenames) / sizeof(char *) 821 && ccp_codenames[code-1] != NULL) 822 printer(arg, " %s", ccp_codenames[code-1]); 823 else 824 printer(arg, " code=0x%x", code); 825 printer(arg, " id=0x%x", id); 826 len -= HEADERLEN; 827 p += HEADERLEN; 828 829 switch (code) { 830 case CONFREQ: 831 case CONFACK: 832 case CONFNAK: 833 case CONFREJ: 834 /* print list of possible compression methods */ 835 while (len >= 2) { 836 code = p[0]; 837 optlen = p[1]; 838 if (optlen < 2 || optlen > len) 839 break; 840 printer(arg, " <"); 841 len -= optlen; 842 optend = p + optlen; 843 switch (code) { 844 case CI_DEFLATE: 845 if (optlen >= CILEN_DEFLATE) { 846 printer(arg, "deflate %d", DEFLATE_SIZE(p[2])); 847 if (DEFLATE_METHOD(p[2]) != DEFLATE_METHOD_VAL) 848 printer(arg, " method %d", DEFLATE_METHOD(p[2])); 849 if (p[3] != DEFLATE_CHK_SEQUENCE) 850 printer(arg, " check %d", p[3]); 851 p += CILEN_DEFLATE; 852 } 853 break; 854 case CI_BSD_COMPRESS: 855 if (optlen >= CILEN_BSD_COMPRESS) { 856 printer(arg, "bsd v%d %d", BSD_VERSION(p[2]), 857 BSD_NBITS(p[2])); 858 p += CILEN_BSD_COMPRESS; 859 } 860 break; 861 case CI_PREDICTOR_1: 862 if (optlen >= CILEN_PREDICTOR_1) { 863 printer(arg, "predictor 1"); 864 p += CILEN_PREDICTOR_1; 865 } 866 break; 867 case CI_PREDICTOR_2: 868 if (optlen >= CILEN_PREDICTOR_2) { 869 printer(arg, "predictor 2"); 870 p += CILEN_PREDICTOR_2; 871 } 872 break; 873 } 874 while (p < optend) 875 printer(arg, " %.2x", *p++); 876 printer(arg, ">"); 877 } 878 break; 879 } 880 881 /* dump out the rest of the packet in hex */ 882 while (--len >= 0) 883 printer(arg, " %.2x", *p++); 884 885 return p - p0; 886} 887 888/* 889 * We have received a packet that the decompressor failed to 890 * decompress. Here we would expect to issue a reset-request, but 891 * Motorola has a patent on resetting the compressor as a result of 892 * detecting an error in the decompressed data after decompression. 893 * (See US patent 5,130,993; international patent publication number 894 * WO 91/10289; Australian patent 73296/91.) 895 * 896 * So we ask the kernel whether the error was detected after 897 * decompression; if it was, we take CCP down, thus disabling 898 * compression :-(, otherwise we issue the reset-request. 899 */ 900void 901ccp_datainput(unit, pkt, len) 902 int unit; 903 u_char *pkt; 904 int len; 905{ 906 fsm *f; 907 908 f = &ccp_fsm[unit]; 909 if (f->state == OPENED) { 910 if (ccp_fatal_error(unit)) { 911 /* 912 * Disable compression by taking CCP down. 913 */ 914 syslog(LOG_ERR, "Lost compression sync: disabling compression"); 915 ccp_close(unit, "Lost compression sync"); 916 } else { 917 /* 918 * Send a reset-request to reset the peer's compressor. 919 * We don't do that if we are still waiting for an 920 * acknowledgement to a previous reset-request. 921 */ 922 if (!(ccp_localstate[f->unit] & RACK_PENDING)) { 923 fsm_sdata(f, CCP_RESETREQ, f->reqid = ++f->id, NULL, 0); 924 TIMEOUT(ccp_rack_timeout, (caddr_t) f, RACKTIMEOUT); 925 ccp_localstate[f->unit] |= RACK_PENDING; 926 } else 927 ccp_localstate[f->unit] |= RREQ_REPEAT; 928 } 929 } 930} 931 932/* 933 * Timeout waiting for reset-ack. 934 */ 935static void 936ccp_rack_timeout(arg) 937 caddr_t arg; 938{ 939 fsm *f = (fsm *) arg; 940 941 if (f->state == OPENED && ccp_localstate[f->unit] & RREQ_REPEAT) { 942 fsm_sdata(f, CCP_RESETREQ, f->reqid, NULL, 0); 943 TIMEOUT(ccp_rack_timeout, (caddr_t) f, RACKTIMEOUT); 944 ccp_localstate[f->unit] &= ~RREQ_REPEAT; 945 } else 946 ccp_localstate[f->unit] &= ~RACK_PENDING; 947} 948 949