1 /*- 2 * Copyright (c) 2000 Semen Ustimenko <semenu@FreeBSD.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $FreeBSD$ 27 */ 28 29 #include <sys/param.h> 30 31 #include <sys/socket.h> 32 #include <netinet/in_systm.h> 33 #include <netinet/in.h> 34 #include <netinet/ip.h> 35 #include <sys/un.h> 36 37 #include <stdio.h> 38 #include <stdlib.h> 39 #include <string.h> 40 #include <termios.h> 41 #include <openssl/rc4.h> 42 43 #include "defs.h" 44 #include "mbuf.h" 45 #include "log.h" 46 #include "timer.h" 47 #include "fsm.h" 48 #include "lqr.h" 49 #include "hdlc.h" 50 #include "lcp.h" 51 #include "ccp.h" 52 #include "throughput.h" 53 #include "layer.h" 54 #include "link.h" 55 #include "chap_ms.h" 56 #include "proto.h" 57 #include "mppe.h" 58 #include "ua.h" 59 #include "descriptor.h" 60 #ifndef NORADIUS 61 #include "radius.h" 62 #endif 63 #include "ncpaddr.h" 64 #include "iplist.h" 65 #include "slcompress.h" 66 #include "ipcp.h" 67 #include "ipv6cp.h" 68 #include "filter.h" 69 #include "mp.h" 70 #include "ncp.h" 71 #include "bundle.h" 72 73 /* 74 * Documentation: 75 * 76 * draft-ietf-pppext-mppe-04.txt 77 * draft-ietf-pppext-mppe-keys-02.txt 78 */ 79 80 #define MPPE_OPT_STATELESS 0x1000000 81 #define MPPE_OPT_COMPRESSED 0x01 82 #define MPPE_OPT_40BIT 0x20 83 #define MPPE_OPT_56BIT 0x80 84 #define MPPE_OPT_128BIT 0x40 85 #define MPPE_OPT_BITMASK 0xe0 86 #define MPPE_OPT_MASK (MPPE_OPT_STATELESS | MPPE_OPT_BITMASK) 87 88 #define MPPE_FLUSHED 0x8000 89 #define MPPE_ENCRYPTED 0x1000 90 #define MPPE_HEADER_BITMASK 0xf000 91 #define MPPE_HEADER_FLAG 0x00ff 92 #define MPPE_HEADER_FLAGMASK 0x00ff 93 #define MPPE_HEADER_FLAGSHIFT 8 94 #define MPPE_HEADER_STATEFUL_KEYCHANGES 16 95 96 struct mppe_state { 97 unsigned stateless : 1; 98 unsigned flushnext : 1; 99 unsigned flushrequired : 1; 100 int cohnum; 101 int keylen; /* 8 or 16 bytes */ 102 int keybits; /* 40, 56 or 128 bits */ 103 char sesskey[MPPE_KEY_LEN]; 104 char mastkey[MPPE_KEY_LEN]; 105 RC4_KEY rc4key; 106 }; 107 108 int MPPE_MasterKeyValid = 0; 109 int MPPE_IsServer = 0; 110 char MPPE_MasterKey[MPPE_KEY_LEN]; 111 112 /* 113 * The peer has missed a packet. Mark the next output frame to be FLUSHED 114 */ 115 static int 116 MPPEResetOutput(void *v) 117 { 118 struct mppe_state *mop = (struct mppe_state *)v; 119 120 if (mop->stateless) 121 log_Printf(LogCCP, "MPPE: Unexpected output channel reset\n"); 122 else { 123 log_Printf(LogCCP, "MPPE: Output channel reset\n"); 124 mop->flushnext = 1; 125 } 126 127 return 0; /* Ask FSM not to ACK */ 128 } 129 130 static void 131 MPPEReduceSessionKey(struct mppe_state *mp) 132 { 133 switch(mp->keybits) { 134 case 40: 135 mp->sesskey[2] = 0x9e; 136 mp->sesskey[1] = 0x26; 137 case 56: 138 mp->sesskey[0] = 0xd1; 139 case 128: 140 break; 141 } 142 } 143 144 static void 145 MPPEKeyChange(struct mppe_state *mp) 146 { 147 char InterimKey[MPPE_KEY_LEN]; 148 RC4_KEY RC4Key; 149 150 GetNewKeyFromSHA(mp->mastkey, mp->sesskey, mp->keylen, InterimKey); 151 RC4_set_key(&RC4Key, mp->keylen, InterimKey); 152 RC4(&RC4Key, mp->keylen, InterimKey, mp->sesskey); 153 154 MPPEReduceSessionKey(mp); 155 } 156 157 static struct mbuf * 158 MPPEOutput(void *v, struct ccp *ccp, struct link *l, int pri, u_short *proto, 159 struct mbuf *mp) 160 { 161 struct mppe_state *mop = (struct mppe_state *)v; 162 struct mbuf *mo; 163 u_short nproto, prefix; 164 int dictinit, ilen, len; 165 char *rp; 166 167 ilen = m_length(mp); 168 dictinit = 0; 169 170 log_Printf(LogDEBUG, "MPPE: Output: Proto %02x (%d bytes)\n", *proto, ilen); 171 if (*proto < 0x21 && *proto > 0xFA) { 172 log_Printf(LogDEBUG, "MPPE: Output: Not encrypting\n"); 173 ccp->compout += ilen; 174 ccp->uncompout += ilen; 175 return mp; 176 } 177 178 log_DumpBp(LogDEBUG, "MPPE: Output: Encrypt packet:", mp); 179 180 /* Get mbuf for prefixes */ 181 mo = m_get(4, MB_CCPOUT); 182 mo->m_next = mp; 183 184 rp = MBUF_CTOP(mo); 185 prefix = MPPE_ENCRYPTED | mop->cohnum; 186 187 if (mop->stateless || 188 (mop->cohnum & MPPE_HEADER_FLAGMASK) == MPPE_HEADER_FLAG) { 189 /* Change our key */ 190 log_Printf(LogDEBUG, "MPPEOutput: Key changed [%d]\n", mop->cohnum); 191 MPPEKeyChange(mop); 192 dictinit = 1; 193 } 194 195 if (mop->stateless || mop->flushnext) { 196 prefix |= MPPE_FLUSHED; 197 dictinit = 1; 198 mop->flushnext = 0; 199 } 200 201 if (dictinit) { 202 /* Initialise our dictionary */ 203 log_Printf(LogDEBUG, "MPPEOutput: Dictionary initialised [%d]\n", 204 mop->cohnum); 205 RC4_set_key(&mop->rc4key, mop->keylen, mop->sesskey); 206 } 207 208 /* Set MPPE packet prefix */ 209 ua_htons(&prefix, rp); 210 211 /* Save encrypted protocol number */ 212 nproto = htons(*proto); 213 RC4(&mop->rc4key, 2, (char *)&nproto, rp + 2); 214 215 /* Encrypt main packet */ 216 rp = MBUF_CTOP(mp); 217 RC4(&mop->rc4key, ilen, rp, rp); 218 219 mop->cohnum++; 220 mop->cohnum &= ~MPPE_HEADER_BITMASK; 221 222 /* Set the protocol number */ 223 *proto = ccp_Proto(ccp); 224 len = m_length(mo); 225 ccp->uncompout += ilen; 226 ccp->compout += len; 227 228 log_Printf(LogDEBUG, "MPPE: Output: Encrypted: Proto %02x (%d bytes)\n", 229 *proto, len); 230 231 return mo; 232 } 233 234 static void 235 MPPEResetInput(void *v) 236 { 237 log_Printf(LogCCP, "MPPE: Unexpected input channel ack\n"); 238 } 239 240 static struct mbuf * 241 MPPEInput(void *v, struct ccp *ccp, u_short *proto, struct mbuf *mp) 242 { 243 struct mppe_state *mip = (struct mppe_state *)v; 244 u_short prefix; 245 char *rp; 246 int dictinit, flushed, ilen, len, n; 247 248 ilen = m_length(mp); 249 dictinit = 0; 250 ccp->compin += ilen; 251 252 log_Printf(LogDEBUG, "MPPE: Input: Proto %02x (%d bytes)\n", *proto, ilen); 253 log_DumpBp(LogDEBUG, "MPPE: Input: Packet:", mp); 254 255 mp = mbuf_Read(mp, &prefix, 2); 256 prefix = ntohs(prefix); 257 flushed = prefix & MPPE_FLUSHED; 258 prefix &= ~flushed; 259 if ((prefix & MPPE_HEADER_BITMASK) != MPPE_ENCRYPTED) { 260 log_Printf(LogERROR, "MPPE: Input: Invalid packet (flags = 0x%x)\n", 261 (prefix & MPPE_HEADER_BITMASK) | flushed); 262 m_freem(mp); 263 return NULL; 264 } 265 266 prefix &= ~MPPE_HEADER_BITMASK; 267 268 if (!flushed && mip->stateless) { 269 log_Printf(LogCCP, "MPPEInput: Packet without MPPE_FLUSHED set" 270 " in stateless mode\n"); 271 flushed = MPPE_FLUSHED; 272 /* Should we really continue ? */ 273 } 274 275 if (mip->stateless) { 276 /* Change our key for each missed packet in stateless mode */ 277 while (prefix != mip->cohnum) { 278 log_Printf(LogDEBUG, "MPPEInput: Key changed [%u]\n", prefix); 279 MPPEKeyChange(mip); 280 /* 281 * mip->cohnum contains what we received last time in stateless 282 * mode. 283 */ 284 mip->cohnum++; 285 mip->cohnum &= ~MPPE_HEADER_BITMASK; 286 } 287 dictinit = 1; 288 } else { 289 if (flushed) { 290 /* 291 * We can always process a flushed packet. 292 * Catch up on any outstanding key changes. 293 */ 294 n = (prefix >> MPPE_HEADER_FLAGSHIFT) - 295 (mip->cohnum >> MPPE_HEADER_FLAGSHIFT); 296 if (n < 0) 297 n += MPPE_HEADER_STATEFUL_KEYCHANGES; 298 while (n--) { 299 log_Printf(LogDEBUG, "MPPEInput: Key changed during catchup [%u]\n", 300 prefix); 301 MPPEKeyChange(mip); 302 } 303 mip->flushrequired = 0; 304 mip->cohnum = prefix; 305 dictinit = 1; 306 } 307 308 if (mip->flushrequired) { 309 /* 310 * Perhaps we should be lenient if 311 * (prefix & MPPE_HEADER_FLAGMASK) == MPPE_HEADER_FLAG 312 * The spec says that we shouldn't be though.... 313 */ 314 log_Printf(LogDEBUG, "MPPE: Not flushed - discarded\n"); 315 fsm_Output(&ccp->fsm, CODE_RESETREQ, ccp->fsm.reqid++, NULL, 0, 316 MB_CCPOUT); 317 m_freem(mp); 318 return NULL; 319 } 320 321 if (prefix != mip->cohnum) { 322 /* 323 * We're in stateful mode and didn't receive the expected 324 * packet. Send a reset request, but don't tell the CCP layer 325 * about it as we don't expect to receive a Reset ACK ! 326 * Guess what... M$ invented this ! 327 */ 328 log_Printf(LogCCP, "MPPE: Input: Got seq %u, not %u\n", 329 prefix, mip->cohnum); 330 fsm_Output(&ccp->fsm, CODE_RESETREQ, ccp->fsm.reqid++, NULL, 0, 331 MB_CCPOUT); 332 mip->flushrequired = 1; 333 m_freem(mp); 334 return NULL; 335 } 336 337 if ((prefix & MPPE_HEADER_FLAGMASK) == MPPE_HEADER_FLAG) { 338 log_Printf(LogDEBUG, "MPPEInput: Key changed [%u]\n", prefix); 339 MPPEKeyChange(mip); 340 dictinit = 1; 341 } else if (flushed) 342 dictinit = 1; 343 344 /* 345 * mip->cohnum contains what we expect to receive next time in stateful 346 * mode. 347 */ 348 mip->cohnum++; 349 mip->cohnum &= ~MPPE_HEADER_BITMASK; 350 } 351 352 if (dictinit) { 353 log_Printf(LogDEBUG, "MPPEInput: Dictionary initialised [%u]\n", prefix); 354 RC4_set_key(&mip->rc4key, mip->keylen, mip->sesskey); 355 } 356 357 mp = mbuf_Read(mp, proto, 2); 358 RC4(&mip->rc4key, 2, (char *)proto, (char *)proto); 359 *proto = ntohs(*proto); 360 361 rp = MBUF_CTOP(mp); 362 len = m_length(mp); 363 RC4(&mip->rc4key, len, rp, rp); 364 365 log_Printf(LogDEBUG, "MPPEInput: Decrypted: Proto %02x (%d bytes)\n", 366 *proto, len); 367 log_DumpBp(LogDEBUG, "MPPEInput: Decrypted: Packet:", mp); 368 369 ccp->uncompin += len; 370 371 return mp; 372 } 373 374 static void 375 MPPEDictSetup(void *v, struct ccp *ccp, u_short proto, struct mbuf *mi) 376 { 377 } 378 379 static const char * 380 MPPEDispOpts(struct fsm_opt *o) 381 { 382 static char buf[70]; 383 u_int32_t val; 384 char ch; 385 int len, n; 386 387 ua_ntohl(o->data, &val); 388 len = 0; 389 if ((n = snprintf(buf, sizeof buf, "value 0x%08x ", (unsigned)val)) > 0) 390 len += n; 391 if (!(val & MPPE_OPT_BITMASK)) { 392 if ((n = snprintf(buf + len, sizeof buf - len, "(0")) > 0) 393 len += n; 394 } else { 395 ch = '('; 396 if (val & MPPE_OPT_128BIT) { 397 if ((n = snprintf(buf + len, sizeof buf - len, "%c128", ch)) > 0) 398 len += n; 399 ch = '/'; 400 } 401 if (val & MPPE_OPT_56BIT) { 402 if ((n = snprintf(buf + len, sizeof buf - len, "%c56", ch)) > 0) 403 len += n; 404 ch = '/'; 405 } 406 if (val & MPPE_OPT_40BIT) { 407 if ((n = snprintf(buf + len, sizeof buf - len, "%c40", ch)) > 0) 408 len += n; 409 ch = '/'; 410 } 411 } 412 413 if ((n = snprintf(buf + len, sizeof buf - len, " bits, state%s", 414 (val & MPPE_OPT_STATELESS) ? "less" : "ful")) > 0) 415 len += n; 416 417 if (val & MPPE_OPT_COMPRESSED) { 418 if ((n = snprintf(buf + len, sizeof buf - len, ", compressed")) > 0) 419 len += n; 420 } 421 422 snprintf(buf + len, sizeof buf - len, ")"); 423 424 return buf; 425 } 426 427 static int 428 MPPEUsable(struct fsm *fp) 429 { 430 struct lcp *lcp; 431 int ok; 432 433 lcp = &fp->link->lcp; 434 ok = (lcp->want_auth == PROTO_CHAP && lcp->want_authtype == 0x81) || 435 (lcp->his_auth == PROTO_CHAP && lcp->his_authtype == 0x81); 436 if (!ok) 437 log_Printf(LogCCP, "MPPE: Not usable without CHAP81\n"); 438 439 return ok; 440 } 441 442 static int 443 MPPERequired(struct fsm *fp) 444 { 445 #ifndef NORADIUS 446 /* 447 * If the radius server gave us RAD_MICROSOFT_MS_MPPE_ENCRYPTION_POLICY, 448 * use that instead of our configuration value. 449 */ 450 if (*fp->bundle->radius.cfg.file && fp->bundle->radius.mppe.policy) 451 return fp->bundle->radius.mppe.policy == MPPE_POLICY_REQUIRED ? 1 : 0; 452 #endif 453 454 return fp->link->ccp.cfg.mppe.required; 455 } 456 457 static u_int32_t 458 MPPE_ConfigVal(struct bundle *bundle, const struct ccp_config *cfg) 459 { 460 u_int32_t val; 461 462 val = cfg->mppe.state == MPPE_STATELESS ? MPPE_OPT_STATELESS : 0; 463 #ifndef NORADIUS 464 /* 465 * If the radius server gave us RAD_MICROSOFT_MS_MPPE_ENCRYPTION_TYPES, 466 * use that instead of our configuration value. 467 */ 468 if (*bundle->radius.cfg.file && bundle->radius.mppe.types) { 469 if (bundle->radius.mppe.types & MPPE_TYPE_40BIT) 470 val |= MPPE_OPT_40BIT; 471 if (bundle->radius.mppe.types & MPPE_TYPE_128BIT) 472 val |= MPPE_OPT_128BIT; 473 } else 474 #endif 475 switch(cfg->mppe.keybits) { 476 case 128: 477 val |= MPPE_OPT_128BIT; 478 break; 479 case 56: 480 val |= MPPE_OPT_56BIT; 481 break; 482 case 40: 483 val |= MPPE_OPT_40BIT; 484 break; 485 case 0: 486 val |= MPPE_OPT_128BIT | MPPE_OPT_56BIT | MPPE_OPT_40BIT; 487 break; 488 } 489 490 return val; 491 } 492 493 /* 494 * What options should we use for our first configure request 495 */ 496 static void 497 MPPEInitOptsOutput(struct bundle *bundle, struct fsm_opt *o, 498 const struct ccp_config *cfg) 499 { 500 u_int32_t mval; 501 502 o->hdr.len = 6; 503 504 if (!MPPE_MasterKeyValid) { 505 log_Printf(LogCCP, "MPPE: MasterKey is invalid," 506 " MPPE is available only with CHAP81 authentication\n"); 507 ua_htonl(0x0, o->data); 508 return; 509 } 510 511 512 mval = MPPE_ConfigVal(bundle, cfg); 513 ua_htonl(&mval, o->data); 514 } 515 516 /* 517 * Our CCP request was NAK'd with the given options 518 */ 519 static int 520 MPPESetOptsOutput(struct bundle *bundle, struct fsm_opt *o, 521 const struct ccp_config *cfg) 522 { 523 u_int32_t mval, peer; 524 525 ua_ntohl(o->data, &peer); 526 527 if (!MPPE_MasterKeyValid) 528 /* Treat their NAK as a REJ */ 529 return MODE_NAK; 530 531 mval = MPPE_ConfigVal(bundle, cfg); 532 533 /* 534 * If we haven't been configured with a specific number of keybits, allow 535 * whatever the peer asks for. 536 */ 537 if (!cfg->mppe.keybits) { 538 mval &= ~MPPE_OPT_BITMASK; 539 mval |= (peer & MPPE_OPT_BITMASK); 540 if (!(mval & MPPE_OPT_BITMASK)) 541 mval |= MPPE_OPT_128BIT; 542 } 543 544 /* Adjust our statelessness */ 545 if (cfg->mppe.state == MPPE_ANYSTATE) { 546 mval &= ~MPPE_OPT_STATELESS; 547 mval |= (peer & MPPE_OPT_STATELESS); 548 } 549 550 ua_htonl(&mval, o->data); 551 552 return MODE_ACK; 553 } 554 555 /* 556 * The peer has requested the given options 557 */ 558 static int 559 MPPESetOptsInput(struct bundle *bundle, struct fsm_opt *o, 560 const struct ccp_config *cfg) 561 { 562 u_int32_t mval, peer; 563 int res = MODE_ACK; 564 565 ua_ntohl(o->data, &peer); 566 if (!MPPE_MasterKeyValid) { 567 if (peer != 0) { 568 peer = 0; 569 ua_htonl(&peer, o->data); 570 return MODE_NAK; 571 } else 572 return MODE_ACK; 573 } 574 575 mval = MPPE_ConfigVal(bundle, cfg); 576 577 if (peer & ~MPPE_OPT_MASK) 578 /* He's asking for bits we don't know about */ 579 res = MODE_NAK; 580 581 if (peer & MPPE_OPT_STATELESS) { 582 if (cfg->mppe.state == MPPE_STATEFUL) 583 /* Peer can't have stateless */ 584 res = MODE_NAK; 585 else 586 /* Peer wants stateless, that's ok */ 587 mval |= MPPE_OPT_STATELESS; 588 } else { 589 if (cfg->mppe.state == MPPE_STATELESS) 590 /* Peer must have stateless */ 591 res = MODE_NAK; 592 else 593 /* Peer doesn't want stateless, that's ok */ 594 mval &= ~MPPE_OPT_STATELESS; 595 } 596 597 /* If we've got a configured number of keybits - the peer must use that */ 598 if (cfg->mppe.keybits) { 599 ua_htonl(&mval, o->data); 600 return peer == mval ? res : MODE_NAK; 601 } 602 603 /* If a specific number of bits hasn't been requested, we'll need to NAK */ 604 switch (peer & MPPE_OPT_BITMASK) { 605 case MPPE_OPT_128BIT: 606 case MPPE_OPT_56BIT: 607 case MPPE_OPT_40BIT: 608 break; 609 default: 610 res = MODE_NAK; 611 } 612 613 /* Suggest the best number of bits */ 614 mval &= ~MPPE_OPT_BITMASK; 615 if (peer & MPPE_OPT_128BIT) 616 mval |= MPPE_OPT_128BIT; 617 else if (peer & MPPE_OPT_56BIT) 618 mval |= MPPE_OPT_56BIT; 619 else if (peer & MPPE_OPT_40BIT) 620 mval |= MPPE_OPT_40BIT; 621 else 622 mval |= MPPE_OPT_128BIT; 623 ua_htonl(&mval, o->data); 624 625 return res; 626 } 627 628 static struct mppe_state * 629 MPPE_InitState(struct fsm_opt *o) 630 { 631 struct mppe_state *mp; 632 u_int32_t val; 633 634 if ((mp = calloc(1, sizeof *mp)) != NULL) { 635 ua_ntohl(o->data, &val); 636 637 switch (val & MPPE_OPT_BITMASK) { 638 case MPPE_OPT_128BIT: 639 mp->keylen = 16; 640 mp->keybits = 128; 641 break; 642 case MPPE_OPT_56BIT: 643 mp->keylen = 8; 644 mp->keybits = 56; 645 break; 646 case MPPE_OPT_40BIT: 647 mp->keylen = 8; 648 mp->keybits = 40; 649 break; 650 default: 651 log_Printf(LogWARN, "Unexpected MPPE options 0x%08x\n", val); 652 free(mp); 653 return NULL; 654 } 655 656 mp->stateless = !!(val & MPPE_OPT_STATELESS); 657 } 658 659 return mp; 660 } 661 662 static void * 663 MPPEInitInput(struct bundle *bundle, struct fsm_opt *o) 664 { 665 struct mppe_state *mip; 666 667 if (!MPPE_MasterKeyValid) { 668 log_Printf(LogWARN, "MPPE: Cannot initialise without CHAP81\n"); 669 return NULL; 670 } 671 672 if ((mip = MPPE_InitState(o)) == NULL) { 673 log_Printf(LogWARN, "MPPEInput: Cannot initialise - unexpected options\n"); 674 return NULL; 675 } 676 677 log_Printf(LogDEBUG, "MPPE: InitInput: %d-bits\n", mip->keybits); 678 679 #ifndef NORADIUS 680 if (*bundle->radius.cfg.file && bundle->radius.mppe.recvkey) { 681 mip->keylen = bundle->radius.mppe.recvkeylen; 682 if (mip->keylen > sizeof mip->mastkey) 683 mip->keylen = sizeof mip->mastkey; 684 memcpy(mip->mastkey, bundle->radius.mppe.recvkey, mip->keylen); 685 } else 686 #endif 687 GetAsymetricStartKey(MPPE_MasterKey, mip->mastkey, mip->keylen, 0, 688 MPPE_IsServer); 689 690 GetNewKeyFromSHA(mip->mastkey, mip->mastkey, mip->keylen, mip->sesskey); 691 692 MPPEReduceSessionKey(mip); 693 694 log_Printf(LogCCP, "MPPE: Input channel initiated\n"); 695 696 if (!mip->stateless) { 697 /* 698 * We need to initialise our dictionary here as the first packet we 699 * receive is unlikely to have the FLUSHED bit set. 700 */ 701 log_Printf(LogDEBUG, "MPPEInitInput: Dictionary initialised [%d]\n", 702 mip->cohnum); 703 RC4_set_key(&mip->rc4key, mip->keylen, mip->sesskey); 704 } else { 705 /* 706 * We do the first key change here as the first packet is expected 707 * to have a sequence number of 0 and we'll therefore not expect 708 * to have to change the key at that point. 709 */ 710 log_Printf(LogDEBUG, "MPPEInitInput: Key changed [%d]\n", mip->cohnum); 711 MPPEKeyChange(mip); 712 } 713 714 return mip; 715 } 716 717 static void * 718 MPPEInitOutput(struct bundle *bundle, struct fsm_opt *o) 719 { 720 struct mppe_state *mop; 721 722 if (!MPPE_MasterKeyValid) { 723 log_Printf(LogWARN, "MPPE: Cannot initialise without CHAP81\n"); 724 return NULL; 725 } 726 727 if ((mop = MPPE_InitState(o)) == NULL) { 728 log_Printf(LogWARN, "MPPEOutput: Cannot initialise - unexpected options\n"); 729 return NULL; 730 } 731 732 log_Printf(LogDEBUG, "MPPE: InitOutput: %d-bits\n", mop->keybits); 733 734 #ifndef NORADIUS 735 if (*bundle->radius.cfg.file && bundle->radius.mppe.sendkey) { 736 mop->keylen = bundle->radius.mppe.sendkeylen; 737 if (mop->keylen > sizeof mop->mastkey) 738 mop->keylen = sizeof mop->mastkey; 739 memcpy(mop->mastkey, bundle->radius.mppe.sendkey, mop->keylen); 740 } else 741 #endif 742 GetAsymetricStartKey(MPPE_MasterKey, mop->mastkey, mop->keylen, 1, 743 MPPE_IsServer); 744 745 GetNewKeyFromSHA(mop->mastkey, mop->mastkey, mop->keylen, mop->sesskey); 746 747 MPPEReduceSessionKey(mop); 748 749 log_Printf(LogCCP, "MPPE: Output channel initiated\n"); 750 751 if (!mop->stateless) { 752 /* 753 * We need to initialise our dictionary now as the first packet we 754 * send won't have the FLUSHED bit set. 755 */ 756 log_Printf(LogDEBUG, "MPPEInitOutput: Dictionary initialised [%d]\n", 757 mop->cohnum); 758 RC4_set_key(&mop->rc4key, mop->keylen, mop->sesskey); 759 } 760 761 return mop; 762 } 763 764 static void 765 MPPETermInput(void *v) 766 { 767 free(v); 768 } 769 770 static void 771 MPPETermOutput(void *v) 772 { 773 free(v); 774 } 775 776 const struct ccp_algorithm MPPEAlgorithm = { 777 TY_MPPE, 778 CCP_NEG_MPPE, 779 MPPEDispOpts, 780 MPPEUsable, 781 MPPERequired, 782 { 783 MPPESetOptsInput, 784 MPPEInitInput, 785 MPPETermInput, 786 MPPEResetInput, 787 MPPEInput, 788 MPPEDictSetup 789 }, 790 { 791 2, 792 MPPEInitOptsOutput, 793 MPPESetOptsOutput, 794 MPPEInitOutput, 795 MPPETermOutput, 796 MPPEResetOutput, 797 MPPEOutput 798 }, 799 }; 800