chap.c revision 67910
1/* 2 * PPP CHAP Module 3 * 4 * Written by Toshiharu OHNO (tony-o@iij.ad.jp) 5 * 6 * Copyright (C) 1993, Internet Initiative Japan, Inc. All rights reserverd. 7 * 8 * Redistribution and use in source and binary forms are permitted 9 * provided that the above copyright notice and this paragraph are 10 * duplicated in all such forms and that any documentation, 11 * advertising materials, and other materials related to such 12 * distribution and use acknowledge that the software was developed 13 * by the Internet Initiative Japan, Inc. The name of the 14 * IIJ may not be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 18 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. 19 * 20 * $FreeBSD: head/usr.sbin/ppp/chap.c 67910 2000-10-30 00:15:04Z brian $ 21 * 22 * TODO: 23 */ 24#include <sys/param.h> 25#include <netinet/in.h> 26#include <netinet/in_systm.h> 27#include <netinet/ip.h> 28#include <sys/un.h> 29 30#include <errno.h> 31#include <fcntl.h> 32#ifdef HAVE_DES 33#include <md4.h> 34#endif 35#include <md5.h> 36#include <paths.h> 37#include <signal.h> 38#include <stdio.h> 39#include <stdlib.h> 40#include <string.h> 41#include <sys/wait.h> 42#include <termios.h> 43#include <unistd.h> 44 45#include "layer.h" 46#include "mbuf.h" 47#include "log.h" 48#include "defs.h" 49#include "timer.h" 50#include "fsm.h" 51#include "proto.h" 52#include "lqr.h" 53#include "hdlc.h" 54#include "lcp.h" 55#include "auth.h" 56#include "async.h" 57#include "throughput.h" 58#include "descriptor.h" 59#include "chap.h" 60#include "iplist.h" 61#include "slcompress.h" 62#include "ipcp.h" 63#include "filter.h" 64#include "ccp.h" 65#include "link.h" 66#include "physical.h" 67#include "mp.h" 68#ifndef NORADIUS 69#include "radius.h" 70#endif 71#include "bundle.h" 72#include "chat.h" 73#include "cbcp.h" 74#include "command.h" 75#include "datalink.h" 76#ifdef HAVE_DES 77#include "chap_ms.h" 78#include "mppe.h" 79#endif 80#include "id.h" 81 82static const char * const chapcodes[] = { 83 "???", "CHALLENGE", "RESPONSE", "SUCCESS", "FAILURE" 84}; 85#define MAXCHAPCODE (sizeof chapcodes / sizeof chapcodes[0] - 1) 86 87static void 88ChapOutput(struct physical *physical, u_int code, u_int id, 89 const u_char *ptr, int count, const char *text) 90{ 91 int plen; 92 struct fsmheader lh; 93 struct mbuf *bp; 94 95 plen = sizeof(struct fsmheader) + count; 96 lh.code = code; 97 lh.id = id; 98 lh.length = htons(plen); 99 bp = m_get(plen, MB_CHAPOUT); 100 memcpy(MBUF_CTOP(bp), &lh, sizeof(struct fsmheader)); 101 if (count) 102 memcpy(MBUF_CTOP(bp) + sizeof(struct fsmheader), ptr, count); 103 log_DumpBp(LogDEBUG, "ChapOutput", bp); 104 if (text == NULL) 105 log_Printf(LogPHASE, "Chap Output: %s\n", chapcodes[code]); 106 else 107 log_Printf(LogPHASE, "Chap Output: %s (%s)\n", chapcodes[code], text); 108 link_PushPacket(&physical->link, bp, physical->dl->bundle, 109 LINK_QUEUES(&physical->link) - 1, PROTO_CHAP); 110} 111 112static char * 113chap_BuildAnswer(char *name, char *key, u_char id, char *challenge, u_char type 114#ifdef HAVE_DES 115 , char *peerchallenge, char *authresponse, int lanman 116#endif 117 ) 118{ 119 char *result, *digest; 120 size_t nlen, klen; 121 122 nlen = strlen(name); 123 klen = strlen(key); 124 125#ifdef HAVE_DES 126 if (type == 0x80) { 127 char expkey[AUTHLEN << 2]; 128 MD4_CTX MD4context; 129 int f; 130 131 if ((result = malloc(1 + nlen + MS_CHAP_RESPONSE_LEN)) == NULL) 132 return result; 133 134 digest = result; /* the response */ 135 *digest++ = MS_CHAP_RESPONSE_LEN; /* 49 */ 136 memcpy(digest + MS_CHAP_RESPONSE_LEN, name, nlen); 137 if (lanman) { 138 memset(digest + 24, '\0', 25); 139 mschap_LANMan(digest, challenge + 1, key); /* LANMan response */ 140 } else { 141 memset(digest, '\0', 25); 142 digest += 24; 143 144 for (f = 0; f < klen; f++) { 145 expkey[2*f] = key[f]; 146 expkey[2*f+1] = '\0'; 147 } 148 /* 149 * ----------- 150 * expkey = | k\0e\0y\0 | 151 * ----------- 152 */ 153 MD4Init(&MD4context); 154 MD4Update(&MD4context, expkey, klen << 1); 155 MD4Final(digest, &MD4context); 156 157 /* 158 * ---- -------- ---------------- ------- ------ 159 * result = | 49 | LANMan | 16 byte digest | 9 * ? | name | 160 * ---- -------- ---------------- ------- ------ 161 */ 162 mschap_NT(digest, challenge + 1); 163 } 164 /* 165 * ---- -------- ------------- ----- ------ 166 * | | struct MS_ChapResponse24 | | 167 * result = | 49 | LANMan | NT digest | 0/1 | name | 168 * ---- -------- ------------- ----- ------ 169 * where only one of LANMan & NT digest are set. 170 */ 171 } else if (type == 0x81) { 172 char expkey[AUTHLEN << 2]; 173 char pwdhash[CHAP81_HASH_LEN]; 174 char pwdhashhash[CHAP81_HASH_LEN]; 175 char *ntresponse; 176 int f; 177 178 if ((result = malloc(1 + nlen + CHAP81_RESPONSE_LEN)) == NULL) 179 return result; 180 181 memset(result, 0, 1 + nlen + CHAP81_RESPONSE_LEN); 182 183 digest = result; 184 *digest++ = CHAP81_RESPONSE_LEN; /* value size */ 185 186 /* Copy our challenge */ 187 memcpy(digest, peerchallenge + 1, CHAP81_CHALLENGE_LEN); 188 189 /* Expand password to Unicode XXX */ 190 for (f = 0; f < klen; f++) { 191 expkey[2*f] = key[f]; 192 expkey[2*f+1] = '\0'; 193 } 194 195 ntresponse = digest + CHAP81_NTRESPONSE_OFF; 196 197 /* Get some needed hashes */ 198 NtPasswordHash(expkey, klen * 2, pwdhash); 199 HashNtPasswordHash(pwdhash, pwdhashhash); 200 201 /* Generate NTRESPONSE to respond on challenge call */ 202 GenerateNTResponse(challenge + 1, peerchallenge + 1, name, nlen, 203 expkey, klen * 2, ntresponse); 204 205 /* Generate MPPE MASTERKEY */ 206 GetMasterKey(pwdhashhash, ntresponse, MPPE_MasterKey); 207 208 /* Generate AUTHRESPONSE to verify on auth success */ 209 GenerateAuthenticatorResponse(expkey, klen * 2, ntresponse, 210 peerchallenge + 1, challenge + 1, name, nlen, 211 authresponse); 212 213 authresponse[CHAP81_AUTHRESPONSE_LEN] = 0; 214 215 memcpy(digest + CHAP81_RESPONSE_LEN, name, nlen); 216 } else 217#endif 218 if ((result = malloc(nlen + 17)) != NULL) { 219 /* Normal MD5 stuff */ 220 MD5_CTX MD5context; 221 222 digest = result; 223 *digest++ = 16; /* value size */ 224 225 MD5Init(&MD5context); 226 MD5Update(&MD5context, &id, 1); 227 MD5Update(&MD5context, key, klen); 228 MD5Update(&MD5context, challenge + 1, *challenge); 229 MD5Final(digest, &MD5context); 230 231 memcpy(digest + 16, name, nlen); 232 /* 233 * ---- -------- ------ 234 * result = | 16 | digest | name | 235 * ---- -------- ------ 236 */ 237 } 238 239 return result; 240} 241 242static void 243chap_StartChild(struct chap *chap, char *prog, const char *name) 244{ 245 char *argv[MAXARGS], *nargv[MAXARGS]; 246 int argc, fd; 247 int in[2], out[2]; 248 pid_t pid; 249 250 if (chap->child.fd != -1) { 251 log_Printf(LogWARN, "Chap: %s: Program already running\n", prog); 252 return; 253 } 254 255 if (pipe(in) == -1) { 256 log_Printf(LogERROR, "Chap: pipe: %s\n", strerror(errno)); 257 return; 258 } 259 260 if (pipe(out) == -1) { 261 log_Printf(LogERROR, "Chap: pipe: %s\n", strerror(errno)); 262 close(in[0]); 263 close(in[1]); 264 return; 265 } 266 267 pid = getpid(); 268 switch ((chap->child.pid = fork())) { 269 case -1: 270 log_Printf(LogERROR, "Chap: fork: %s\n", strerror(errno)); 271 close(in[0]); 272 close(in[1]); 273 close(out[0]); 274 close(out[1]); 275 chap->child.pid = 0; 276 return; 277 278 case 0: 279 timer_TermService(); 280 281 if ((argc = command_Interpret(prog, strlen(prog), argv)) <= 0) { 282 if (argc < 0) { 283 log_Printf(LogWARN, "CHAP: Invalid command syntax\n"); 284 _exit(255); 285 } 286 _exit(0); 287 } 288 289 close(in[1]); 290 close(out[0]); 291 if (out[1] == STDIN_FILENO) 292 out[1] = dup(out[1]); 293 dup2(in[0], STDIN_FILENO); 294 dup2(out[1], STDOUT_FILENO); 295 close(STDERR_FILENO); 296 if (open(_PATH_DEVNULL, O_RDWR) != STDERR_FILENO) { 297 log_Printf(LogALERT, "Chap: Failed to open %s: %s\n", 298 _PATH_DEVNULL, strerror(errno)); 299 exit(1); 300 } 301 for (fd = getdtablesize(); fd > STDERR_FILENO; fd--) 302 fcntl(fd, F_SETFD, 1); 303#ifndef NOSUID 304 setuid(ID0realuid()); 305#endif 306 command_Expand(nargv, argc, (char const *const *)argv, 307 chap->auth.physical->dl->bundle, 0, pid); 308 execvp(nargv[0], nargv); 309 printf("exec() of %s failed: %s\n", nargv[0], strerror(errno)); 310 _exit(255); 311 312 default: 313 close(in[0]); 314 close(out[1]); 315 chap->child.fd = out[0]; 316 chap->child.buf.len = 0; 317 write(in[1], chap->auth.in.name, strlen(chap->auth.in.name)); 318 write(in[1], "\n", 1); 319 write(in[1], chap->challenge.peer + 1, *chap->challenge.peer); 320 write(in[1], "\n", 1); 321 write(in[1], name, strlen(name)); 322 write(in[1], "\n", 1); 323 close(in[1]); 324 break; 325 } 326} 327 328static void 329chap_Cleanup(struct chap *chap, int sig) 330{ 331 if (chap->child.pid) { 332 int status; 333 334 close(chap->child.fd); 335 chap->child.fd = -1; 336 if (sig) 337 kill(chap->child.pid, SIGTERM); 338 chap->child.pid = 0; 339 chap->child.buf.len = 0; 340 341 if (wait(&status) == -1) 342 log_Printf(LogERROR, "Chap: wait: %s\n", strerror(errno)); 343 else if (WIFSIGNALED(status)) 344 log_Printf(LogWARN, "Chap: Child received signal %d\n", WTERMSIG(status)); 345 else if (WIFEXITED(status) && WEXITSTATUS(status)) 346 log_Printf(LogERROR, "Chap: Child exited %d\n", WEXITSTATUS(status)); 347 } 348 *chap->challenge.local = *chap->challenge.peer = '\0'; 349#ifdef HAVE_DES 350 chap->peertries = 0; 351#endif 352} 353 354static void 355chap_Respond(struct chap *chap, char *name, char *key, u_char type 356#ifdef HAVE_DES 357 , int lm 358#endif 359 ) 360{ 361 u_char *ans; 362 363 ans = chap_BuildAnswer(name, key, chap->auth.id, chap->challenge.peer, type 364#ifdef HAVE_DES 365 , chap->challenge.local, chap->authresponse, lm 366#endif 367 ); 368 369 if (ans) { 370 ChapOutput(chap->auth.physical, CHAP_RESPONSE, chap->auth.id, 371 ans, *ans + 1 + strlen(name), name); 372#ifdef HAVE_DES 373 chap->NTRespSent = !lm; 374#endif 375 free(ans); 376 } else 377 ChapOutput(chap->auth.physical, CHAP_FAILURE, chap->auth.id, 378 "Out of memory!", 14, NULL); 379} 380 381static int 382chap_UpdateSet(struct fdescriptor *d, fd_set *r, fd_set *w, fd_set *e, int *n) 383{ 384 struct chap *chap = descriptor2chap(d); 385 386 if (r && chap && chap->child.fd != -1) { 387 FD_SET(chap->child.fd, r); 388 if (*n < chap->child.fd + 1) 389 *n = chap->child.fd + 1; 390 log_Printf(LogTIMER, "Chap: fdset(r) %d\n", chap->child.fd); 391 return 1; 392 } 393 394 return 0; 395} 396 397static int 398chap_IsSet(struct fdescriptor *d, const fd_set *fdset) 399{ 400 struct chap *chap = descriptor2chap(d); 401 402 return chap && chap->child.fd != -1 && FD_ISSET(chap->child.fd, fdset); 403} 404 405static void 406chap_Read(struct fdescriptor *d, struct bundle *bundle, const fd_set *fdset) 407{ 408 struct chap *chap = descriptor2chap(d); 409 int got; 410 411 got = read(chap->child.fd, chap->child.buf.ptr + chap->child.buf.len, 412 sizeof chap->child.buf.ptr - chap->child.buf.len - 1); 413 if (got == -1) { 414 log_Printf(LogERROR, "Chap: Read: %s\n", strerror(errno)); 415 chap_Cleanup(chap, SIGTERM); 416 } else if (got == 0) { 417 log_Printf(LogWARN, "Chap: Read: Child terminated connection\n"); 418 chap_Cleanup(chap, SIGTERM); 419 } else { 420 char *name, *key, *end; 421 422 chap->child.buf.len += got; 423 chap->child.buf.ptr[chap->child.buf.len] = '\0'; 424 name = chap->child.buf.ptr; 425 name += strspn(name, " \t"); 426 if ((key = strchr(name, '\n')) == NULL) 427 end = NULL; 428 else 429 end = strchr(++key, '\n'); 430 431 if (end == NULL) { 432 if (chap->child.buf.len == sizeof chap->child.buf.ptr - 1) { 433 log_Printf(LogWARN, "Chap: Read: Input buffer overflow\n"); 434 chap_Cleanup(chap, SIGTERM); 435 } 436 } else { 437#ifdef HAVE_DES 438 int lanman = chap->auth.physical->link.lcp.his_authtype == 0x80 && 439 ((chap->NTRespSent && 440 IsAccepted(chap->auth.physical->link.lcp.cfg.chap80lm)) || 441 !IsAccepted(chap->auth.physical->link.lcp.cfg.chap80nt)); 442#endif 443 444 while (end >= name && strchr(" \t\r\n", *end)) 445 *end-- = '\0'; 446 end = key - 1; 447 while (end >= name && strchr(" \t\r\n", *end)) 448 *end-- = '\0'; 449 key += strspn(key, " \t"); 450 451 chap_Respond(chap, name, key, chap->auth.physical->link.lcp.his_authtype 452#ifdef HAVE_DES 453 , lanman 454#endif 455 ); 456 chap_Cleanup(chap, 0); 457 } 458 } 459} 460 461static int 462chap_Write(struct fdescriptor *d, struct bundle *bundle, const fd_set *fdset) 463{ 464 /* We never want to write here ! */ 465 log_Printf(LogALERT, "chap_Write: Internal error: Bad call !\n"); 466 return 0; 467} 468 469static void 470chap_ChallengeInit(struct authinfo *authp) 471{ 472 struct chap *chap = auth2chap(authp); 473 int len, i; 474 char *cp; 475 476 len = strlen(authp->physical->dl->bundle->cfg.auth.name); 477 478 if (!*chap->challenge.local) { 479 randinit(); 480 cp = chap->challenge.local; 481 482#ifndef NORADIUS 483 if (*authp->physical->dl->bundle->radius.cfg.file) { 484 /* For radius, our challenge is 16 readable NUL terminated bytes :*/ 485 *cp++ = 16; 486 for (i = 0; i < 16; i++) 487 *cp++ = (random() % 10) + '0'; 488 } else 489#endif 490 { 491#ifdef HAVE_DES 492 if (authp->physical->link.lcp.want_authtype == 0x80) 493 *cp++ = 8; /* MS does 8 byte callenges :-/ */ 494 else if (authp->physical->link.lcp.want_authtype == 0x81) 495 *cp++ = 16; /* MS-CHAP-V2 does 16 bytes challenges */ 496 else 497#endif 498 *cp++ = random() % (CHAPCHALLENGELEN-16) + 16; 499 for (i = 0; i < *chap->challenge.local; i++) 500 *cp++ = random() & 0xff; 501 } 502 memcpy(cp, authp->physical->dl->bundle->cfg.auth.name, len); 503 } 504} 505 506static void 507chap_Challenge(struct authinfo *authp) 508{ 509 struct chap *chap = auth2chap(authp); 510 int len; 511 512 log_Printf(LogDEBUG, "CHAP%02X: Challenge\n", authp->physical->link.lcp.want_authtype); 513 514 len = strlen(authp->physical->dl->bundle->cfg.auth.name); 515 516 /* Generate new local challenge value */ 517 if (!*chap->challenge.local) 518 chap_ChallengeInit(authp); 519 520#ifdef HAVE_DES 521 if (authp->physical->link.lcp.want_authtype == 0x81) 522 ChapOutput(authp->physical, CHAP_CHALLENGE, authp->id, 523 chap->challenge.local, 1 + *chap->challenge.local, NULL); 524 else 525#endif 526 ChapOutput(authp->physical, CHAP_CHALLENGE, authp->id, 527 chap->challenge.local, 1 + *chap->challenge.local + len, NULL); 528} 529 530static void 531chap_Success(struct authinfo *authp) 532{ 533 char *msg; 534 datalink_GotAuthname(authp->physical->dl, authp->in.name); 535#ifdef HAVE_DES 536 if (authp->physical->link.lcp.want_authtype == 0x81) { 537 msg = auth2chap(authp)->authresponse; 538 MPPE_MasterKeyValid = 1; 539 } else 540#endif 541 msg = "Welcome!!"; 542 543 ChapOutput(authp->physical, CHAP_SUCCESS, authp->id, msg, strlen(msg) + 1, 544 NULL); 545 546 authp->physical->link.lcp.auth_ineed = 0; 547 if (Enabled(authp->physical->dl->bundle, OPT_UTMP)) 548 physical_Login(authp->physical, authp->in.name); 549 550 if (authp->physical->link.lcp.auth_iwait == 0) 551 /* 552 * Either I didn't need to authenticate, or I've already been 553 * told that I got the answer right. 554 */ 555 datalink_AuthOk(authp->physical->dl); 556} 557 558static void 559chap_Failure(struct authinfo *authp) 560{ 561#ifdef HAVE_DES 562 char buf[1024]; 563#endif 564 char *msg; 565 566#ifdef HAVE_DES 567 if (authp->physical->link.lcp.want_authtype == 0x81) { 568 int i; 569 570 msg = buf; 571 msg += sprintf(buf, "E=691 R=0 C="); 572 for (i=0; i<16; i++) 573 msg += sprintf(msg, "%02X", *(auth2chap(authp)->challenge.local+1+i)); 574 575 sprintf(msg, " V=3 M=Invalid!"); 576 msg = buf; 577 } else 578#endif 579 msg = "Invalid!!"; 580 581 ChapOutput(authp->physical, CHAP_FAILURE, authp->id, msg, strlen(msg) + 1, 582 NULL); 583 datalink_AuthNotOk(authp->physical->dl); 584} 585 586static int 587chap_Cmp(u_char type, char *myans, int mylen, char *hisans, int hislen 588#ifdef HAVE_DES 589 , int lm 590#endif 591 ) 592{ 593 if (mylen != hislen) 594 return 0; 595#ifdef HAVE_DES 596 else if (type == 0x80) { 597 int off = lm ? 0 : 24; 598 599 if (memcmp(myans + off, hisans + off, 24)) 600 return 0; 601 } 602#endif 603 else if (memcmp(myans, hisans, mylen)) 604 return 0; 605 606 return 1; 607} 608 609#ifdef HAVE_DES 610static int 611chap_HaveAnotherGo(struct chap *chap) 612{ 613 if (++chap->peertries < 3) { 614 /* Give the peer another shot */ 615 *chap->challenge.local = '\0'; 616 chap_Challenge(&chap->auth); 617 return 1; 618 } 619 620 return 0; 621} 622#endif 623 624void 625chap_Init(struct chap *chap, struct physical *p) 626{ 627 chap->desc.type = CHAP_DESCRIPTOR; 628 chap->desc.UpdateSet = chap_UpdateSet; 629 chap->desc.IsSet = chap_IsSet; 630 chap->desc.Read = chap_Read; 631 chap->desc.Write = chap_Write; 632 chap->child.pid = 0; 633 chap->child.fd = -1; 634 auth_Init(&chap->auth, p, chap_Challenge, chap_Success, chap_Failure); 635 *chap->challenge.local = *chap->challenge.peer = '\0'; 636#ifdef HAVE_DES 637 chap->NTRespSent = 0; 638 chap->peertries = 0; 639#endif 640} 641 642void 643chap_ReInit(struct chap *chap) 644{ 645 chap_Cleanup(chap, SIGTERM); 646} 647 648struct mbuf * 649chap_Input(struct bundle *bundle, struct link *l, struct mbuf *bp) 650{ 651 struct physical *p = link2physical(l); 652 struct chap *chap = &p->dl->chap; 653 char *name, *key, *ans; 654 int len, nlen; 655 u_char alen; 656#ifdef HAVE_DES 657 int lanman; 658#endif 659 660 if (p == NULL) { 661 log_Printf(LogERROR, "chap_Input: Not a physical link - dropped\n"); 662 m_freem(bp); 663 return NULL; 664 } 665 666 if (bundle_Phase(bundle) != PHASE_NETWORK && 667 bundle_Phase(bundle) != PHASE_AUTHENTICATE) { 668 log_Printf(LogPHASE, "Unexpected chap input - dropped !\n"); 669 m_freem(bp); 670 return NULL; 671 } 672 673 m_settype(bp, MB_CHAPIN); 674 if ((bp = auth_ReadHeader(&chap->auth, bp)) == NULL && 675 ntohs(chap->auth.in.hdr.length) == 0) 676 log_Printf(LogWARN, "Chap Input: Truncated header !\n"); 677 else if (chap->auth.in.hdr.code == 0 || chap->auth.in.hdr.code > MAXCHAPCODE) 678 log_Printf(LogPHASE, "Chap Input: %d: Bad CHAP code !\n", 679 chap->auth.in.hdr.code); 680 else { 681 len = m_length(bp); 682 ans = NULL; 683 684 if (chap->auth.in.hdr.code != CHAP_CHALLENGE && 685 chap->auth.id != chap->auth.in.hdr.id && 686 Enabled(bundle, OPT_IDCHECK)) { 687 /* Wrong conversation dude ! */ 688 log_Printf(LogPHASE, "Chap Input: %s dropped (got id %d, not %d)\n", 689 chapcodes[chap->auth.in.hdr.code], chap->auth.in.hdr.id, 690 chap->auth.id); 691 m_freem(bp); 692 return NULL; 693 } 694 chap->auth.id = chap->auth.in.hdr.id; /* We respond with this id */ 695 696#ifdef HAVE_DES 697 lanman = 0; 698#endif 699 switch (chap->auth.in.hdr.code) { 700 case CHAP_CHALLENGE: 701 bp = mbuf_Read(bp, &alen, 1); 702 len -= alen + 1; 703 if (len < 0) { 704 log_Printf(LogERROR, "Chap Input: Truncated challenge !\n"); 705 m_freem(bp); 706 return NULL; 707 } 708 *chap->challenge.peer = alen; 709 bp = mbuf_Read(bp, chap->challenge.peer + 1, alen); 710 bp = auth_ReadName(&chap->auth, bp, len); 711#ifdef HAVE_DES 712 lanman = p->link.lcp.his_authtype == 0x80 && 713 ((chap->NTRespSent && IsAccepted(p->link.lcp.cfg.chap80lm)) || 714 !IsAccepted(p->link.lcp.cfg.chap80nt)); 715 716 /* Generate local challenge value */ 717 chap_ChallengeInit(&chap->auth); 718#endif 719 break; 720 721 case CHAP_RESPONSE: 722 auth_StopTimer(&chap->auth); 723 bp = mbuf_Read(bp, &alen, 1); 724 len -= alen + 1; 725 if (len < 0) { 726 log_Printf(LogERROR, "Chap Input: Truncated response !\n"); 727 m_freem(bp); 728 return NULL; 729 } 730 if ((ans = malloc(alen + 2)) == NULL) { 731 log_Printf(LogERROR, "Chap Input: Out of memory !\n"); 732 m_freem(bp); 733 return NULL; 734 } 735 *ans = chap->auth.id; 736 bp = mbuf_Read(bp, ans + 1, alen); 737 ans[alen+1] = '\0'; 738 bp = auth_ReadName(&chap->auth, bp, len); 739#ifdef HAVE_DES 740 lanman = p->link.lcp.want_authtype == 0x80 && 741 alen == 49 && ans[alen] == 0; 742#endif 743 break; 744 745 case CHAP_SUCCESS: 746 case CHAP_FAILURE: 747 /* chap->auth.in.name is already set up at CHALLENGE time */ 748 if ((ans = malloc(len + 1)) == NULL) { 749 log_Printf(LogERROR, "Chap Input: Out of memory !\n"); 750 m_freem(bp); 751 return NULL; 752 } 753 bp = mbuf_Read(bp, ans, len); 754 ans[len] = '\0'; 755 break; 756 } 757 758 switch (chap->auth.in.hdr.code) { 759 case CHAP_CHALLENGE: 760 case CHAP_RESPONSE: 761 if (*chap->auth.in.name) 762 log_Printf(LogPHASE, "Chap Input: %s (%d bytes from %s%s)\n", 763 chapcodes[chap->auth.in.hdr.code], alen, 764 chap->auth.in.name, 765#ifdef HAVE_DES 766 lanman && chap->auth.in.hdr.code == CHAP_RESPONSE ? 767 " - lanman" : 768#endif 769 ""); 770 else 771 log_Printf(LogPHASE, "Chap Input: %s (%d bytes%s)\n", 772 chapcodes[chap->auth.in.hdr.code], alen, 773#ifdef HAVE_DES 774 lanman && chap->auth.in.hdr.code == CHAP_RESPONSE ? 775 " - lanman" : 776#endif 777 ""); 778 break; 779 780 case CHAP_SUCCESS: 781 case CHAP_FAILURE: 782 if (*ans) 783 log_Printf(LogPHASE, "Chap Input: %s (%s)\n", 784 chapcodes[chap->auth.in.hdr.code], ans); 785 else 786 log_Printf(LogPHASE, "Chap Input: %s\n", 787 chapcodes[chap->auth.in.hdr.code]); 788 break; 789 } 790 791 switch (chap->auth.in.hdr.code) { 792 case CHAP_CHALLENGE: 793 if (*bundle->cfg.auth.key == '!' && bundle->cfg.auth.key[1] != '!') 794 chap_StartChild(chap, bundle->cfg.auth.key + 1, 795 bundle->cfg.auth.name); 796 else 797 chap_Respond(chap, bundle->cfg.auth.name, bundle->cfg.auth.key + 798 (*bundle->cfg.auth.key == '!' ? 1 : 0), 799 p->link.lcp.his_authtype 800#ifdef HAVE_DES 801 , lanman 802#endif 803 ); 804 break; 805 806 case CHAP_RESPONSE: 807 name = chap->auth.in.name; 808 nlen = strlen(name); 809#ifndef NORADIUS 810 if (*bundle->radius.cfg.file) { 811 u_char end; 812 813 end = chap->challenge.local[*chap->challenge.local+1]; 814 chap->challenge.local[*chap->challenge.local+1] = '\0'; 815 radius_Authenticate(&bundle->radius, &chap->auth, 816 chap->auth.in.name, ans, 817 chap->challenge.local + 1); 818 chap->challenge.local[*chap->challenge.local+1] = end; 819 } else 820#endif 821 { 822 key = auth_GetSecret(bundle, name, nlen, p); 823 if (key) { 824 char *myans; 825#ifdef HAVE_DES 826 if (p->link.lcp.want_authtype == 0x80 && 827 lanman && !IsEnabled(p->link.lcp.cfg.chap80lm)) { 828 log_Printf(LogPHASE, "Auth failure: LANMan not enabled\n"); 829 if (chap_HaveAnotherGo(chap)) 830 break; 831 key = NULL; 832 } else if (p->link.lcp.want_authtype == 0x80 && 833 !lanman && !IsEnabled(p->link.lcp.cfg.chap80nt)) { 834 log_Printf(LogPHASE, "Auth failure: mschap not enabled\n"); 835 if (chap_HaveAnotherGo(chap)) 836 break; 837 key = NULL; 838 } else if (p->link.lcp.want_authtype == 0x81 && 839 !IsEnabled(p->link.lcp.cfg.chap81)) { 840 log_Printf(LogPHASE, "Auth failure: CHAP81 not enabled\n"); 841 key = NULL; 842 } else 843#endif 844 { 845#ifdef HAVE_DES 846 /* Get peer's challenge */ 847 if (p->link.lcp.want_authtype == 0x81) { 848 chap->challenge.peer[0] = CHAP81_CHALLENGE_LEN; 849 memcpy(chap->challenge.peer + 1, ans + 1, CHAP81_CHALLENGE_LEN); 850 } 851#endif 852 853 myans = chap_BuildAnswer(name, key, chap->auth.id, 854 chap->challenge.local, 855 p->link.lcp.want_authtype 856#ifdef HAVE_DES 857 , chap->challenge.peer, 858 chap->authresponse, lanman 859#endif 860 ); 861 if (myans == NULL) 862 key = NULL; 863 else { 864 if (!chap_Cmp(p->link.lcp.want_authtype, myans + 1, *myans, 865 ans + 1, alen 866#ifdef HAVE_DES 867 , lanman 868#endif 869 )) 870 key = NULL; 871 free(myans); 872 } 873 } 874 } 875 876 if (key) 877 chap_Success(&chap->auth); 878 else 879 chap_Failure(&chap->auth); 880 } 881 882 break; 883 884 case CHAP_SUCCESS: 885 if (p->link.lcp.auth_iwait == PROTO_CHAP) { 886 p->link.lcp.auth_iwait = 0; 887 if (p->link.lcp.auth_ineed == 0) { 888#ifdef HAVE_DES 889 if (p->link.lcp.his_authtype == 0x81) { 890 if (strncmp(ans, chap->authresponse, 42)) { 891 datalink_AuthNotOk(p->dl); 892 log_Printf(LogDEBUG, "CHAP81: AuthenticatorResponse: (%s) != ans: (%s)\n", chap->authresponse, ans); 893 894 } else { 895 /* Successful login */ 896 MPPE_MasterKeyValid = 1; 897 datalink_AuthOk(p->dl); 898 } 899 } else 900#endif 901 /* 902 * We've succeeded in our ``login'' 903 * If we're not expecting the peer to authenticate (or he already 904 * has), proceed to network phase. 905 */ 906 datalink_AuthOk(p->dl); 907 } 908 } 909 break; 910 911 case CHAP_FAILURE: 912 datalink_AuthNotOk(p->dl); 913 break; 914 } 915 free(ans); 916 } 917 918 m_freem(bp); 919 return NULL; 920} 921