1 /* 2 * Copyright (c) 1997-2008 Kungliga Tekniska Högskolan 3 * (Royal Institute of Technology, Stockholm, Sweden). 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * 3. Neither the name of the Institute nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #include "kdc_locl.h" 35 36 /* 37 * return the realm of a krbtgt-ticket or NULL 38 */ 39 40 static Realm 41 get_krbtgt_realm(const PrincipalName *p) 42 { 43 if(p->name_string.len == 2 44 && strcmp(p->name_string.val[0], KRB5_TGS_NAME) == 0) 45 return p->name_string.val[1]; 46 else 47 return NULL; 48 } 49 50 /* 51 * The KDC might add a signed path to the ticket authorization data 52 * field. This is to avoid server impersonating clients and the 53 * request constrained delegation. 54 * 55 * This is done by storing a KRB5_AUTHDATA_IF_RELEVANT with a single 56 * entry of type KRB5SignedPath. 57 */ 58 59 static krb5_error_code 60 find_KRB5SignedPath(krb5_context context, 61 const AuthorizationData *ad, 62 krb5_data *data) 63 { 64 AuthorizationData child; 65 krb5_error_code ret; 66 int pos; 67 68 if (ad == NULL || ad->len == 0) 69 return KRB5KDC_ERR_PADATA_TYPE_NOSUPP; 70 71 pos = ad->len - 1; 72 73 if (ad->val[pos].ad_type != KRB5_AUTHDATA_IF_RELEVANT) 74 return KRB5KDC_ERR_PADATA_TYPE_NOSUPP; 75 76 ret = decode_AuthorizationData(ad->val[pos].ad_data.data, 77 ad->val[pos].ad_data.length, 78 &child, 79 NULL); 80 if (ret) { 81 krb5_set_error_message(context, ret, "Failed to decode " 82 "IF_RELEVANT with %d", ret); 83 return ret; 84 } 85 86 if (child.len != 1) { 87 free_AuthorizationData(&child); 88 return KRB5KDC_ERR_PADATA_TYPE_NOSUPP; 89 } 90 91 if (child.val[0].ad_type != KRB5_AUTHDATA_SIGNTICKET) { 92 free_AuthorizationData(&child); 93 return KRB5KDC_ERR_PADATA_TYPE_NOSUPP; 94 } 95 96 if (data) 97 ret = der_copy_octet_string(&child.val[0].ad_data, data); 98 free_AuthorizationData(&child); 99 return ret; 100 } 101 102 krb5_error_code 103 _kdc_add_KRB5SignedPath(krb5_context context, 104 krb5_kdc_configuration *config, 105 hdb_entry_ex *krbtgt, 106 krb5_enctype enctype, 107 krb5_principal client, 108 krb5_const_principal server, 109 krb5_principals principals, 110 EncTicketPart *tkt) 111 { 112 krb5_error_code ret; 113 KRB5SignedPath sp; 114 krb5_data data; 115 krb5_crypto crypto = NULL; 116 size_t size = 0; 117 118 if (server && principals) { 119 ret = add_Principals(principals, server); 120 if (ret) 121 return ret; 122 } 123 124 { 125 KRB5SignedPathData spd; 126 127 spd.client = client; 128 spd.authtime = tkt->authtime; 129 spd.delegated = principals; 130 spd.method_data = NULL; 131 132 ASN1_MALLOC_ENCODE(KRB5SignedPathData, data.data, data.length, 133 &spd, &size, ret); 134 if (ret) 135 return ret; 136 if (data.length != size) 137 krb5_abortx(context, "internal asn.1 encoder error"); 138 } 139 140 { 141 Key *key; 142 ret = hdb_enctype2key(context, &krbtgt->entry, enctype, &key); 143 if (ret == 0) 144 ret = krb5_crypto_init(context, &key->key, 0, &crypto); 145 if (ret) { 146 free(data.data); 147 return ret; 148 } 149 } 150 151 /* 152 * Fill in KRB5SignedPath 153 */ 154 155 sp.etype = enctype; 156 sp.delegated = principals; 157 sp.method_data = NULL; 158 159 ret = krb5_create_checksum(context, crypto, KRB5_KU_KRB5SIGNEDPATH, 0, 160 data.data, data.length, &sp.cksum); 161 krb5_crypto_destroy(context, crypto); 162 free(data.data); 163 if (ret) 164 return ret; 165 166 ASN1_MALLOC_ENCODE(KRB5SignedPath, data.data, data.length, &sp, &size, ret); 167 free_Checksum(&sp.cksum); 168 if (ret) 169 return ret; 170 if (data.length != size) 171 krb5_abortx(context, "internal asn.1 encoder error"); 172 173 174 /* 175 * Add IF-RELEVANT(KRB5SignedPath) to the last slot in 176 * authorization data field. 177 */ 178 179 ret = _kdc_tkt_add_if_relevant_ad(context, tkt, 180 KRB5_AUTHDATA_SIGNTICKET, &data); 181 krb5_data_free(&data); 182 183 return ret; 184 } 185 186 static krb5_error_code 187 check_KRB5SignedPath(krb5_context context, 188 krb5_kdc_configuration *config, 189 hdb_entry_ex *krbtgt, 190 krb5_principal cp, 191 EncTicketPart *tkt, 192 krb5_principals *delegated, 193 int *signedpath) 194 { 195 krb5_error_code ret; 196 krb5_data data; 197 krb5_crypto crypto = NULL; 198 199 if (delegated) 200 *delegated = NULL; 201 202 ret = find_KRB5SignedPath(context, tkt->authorization_data, &data); 203 if (ret == 0) { 204 KRB5SignedPathData spd; 205 KRB5SignedPath sp; 206 size_t size = 0; 207 208 ret = decode_KRB5SignedPath(data.data, data.length, &sp, NULL); 209 krb5_data_free(&data); 210 if (ret) 211 return ret; 212 213 spd.client = cp; 214 spd.authtime = tkt->authtime; 215 spd.delegated = sp.delegated; 216 spd.method_data = sp.method_data; 217 218 ASN1_MALLOC_ENCODE(KRB5SignedPathData, data.data, data.length, 219 &spd, &size, ret); 220 if (ret) { 221 free_KRB5SignedPath(&sp); 222 return ret; 223 } 224 if (data.length != size) 225 krb5_abortx(context, "internal asn.1 encoder error"); 226 227 { 228 Key *key; 229 ret = hdb_enctype2key(context, &krbtgt->entry, sp.etype, &key); 230 if (ret == 0) 231 ret = krb5_crypto_init(context, &key->key, 0, &crypto); 232 if (ret) { 233 free(data.data); 234 free_KRB5SignedPath(&sp); 235 return ret; 236 } 237 } 238 ret = krb5_verify_checksum(context, crypto, KRB5_KU_KRB5SIGNEDPATH, 239 data.data, data.length, 240 &sp.cksum); 241 krb5_crypto_destroy(context, crypto); 242 free(data.data); 243 if (ret) { 244 free_KRB5SignedPath(&sp); 245 kdc_log(context, config, 5, 246 "KRB5SignedPath not signed correctly, not marking as signed"); 247 return 0; 248 } 249 250 if (delegated && sp.delegated) { 251 252 *delegated = malloc(sizeof(*sp.delegated)); 253 if (*delegated == NULL) { 254 free_KRB5SignedPath(&sp); 255 return ENOMEM; 256 } 257 258 ret = copy_Principals(*delegated, sp.delegated); 259 if (ret) { 260 free_KRB5SignedPath(&sp); 261 free(*delegated); 262 *delegated = NULL; 263 return ret; 264 } 265 } 266 free_KRB5SignedPath(&sp); 267 268 *signedpath = 1; 269 } 270 271 return 0; 272 } 273 274 /* 275 * 276 */ 277 278 static krb5_error_code 279 check_PAC(krb5_context context, 280 krb5_kdc_configuration *config, 281 const krb5_principal client_principal, 282 const krb5_principal delegated_proxy_principal, 283 hdb_entry_ex *client, 284 hdb_entry_ex *server, 285 hdb_entry_ex *krbtgt, 286 const EncryptionKey *server_check_key, 287 const EncryptionKey *krbtgt_check_key, 288 const EncryptionKey *server_sign_key, 289 const EncryptionKey *krbtgt_sign_key, 290 EncTicketPart *tkt, 291 krb5_data *rspac, 292 int *signedpath) 293 { 294 AuthorizationData *ad = tkt->authorization_data; 295 unsigned i, j; 296 krb5_error_code ret; 297 298 if (ad == NULL || ad->len == 0) 299 return 0; 300 301 for (i = 0; i < ad->len; i++) { 302 AuthorizationData child; 303 304 if (ad->val[i].ad_type != KRB5_AUTHDATA_IF_RELEVANT) 305 continue; 306 307 ret = decode_AuthorizationData(ad->val[i].ad_data.data, 308 ad->val[i].ad_data.length, 309 &child, 310 NULL); 311 if (ret) { 312 krb5_set_error_message(context, ret, "Failed to decode " 313 "IF_RELEVANT with %d", ret); 314 return ret; 315 } 316 for (j = 0; j < child.len; j++) { 317 318 if (child.val[j].ad_type == KRB5_AUTHDATA_WIN2K_PAC) { 319 int signed_pac = 0; 320 krb5_pac pac; 321 322 /* Found PAC */ 323 ret = krb5_pac_parse(context, 324 child.val[j].ad_data.data, 325 child.val[j].ad_data.length, 326 &pac); 327 free_AuthorizationData(&child); 328 if (ret) 329 return ret; 330 331 ret = krb5_pac_verify(context, pac, tkt->authtime, 332 client_principal, 333 server_check_key, krbtgt_check_key); 334 if (ret) { 335 krb5_pac_free(context, pac); 336 return ret; 337 } 338 339 ret = _kdc_pac_verify(context, client_principal, 340 delegated_proxy_principal, 341 client, server, krbtgt, &pac, &signed_pac); 342 if (ret) { 343 krb5_pac_free(context, pac); 344 return ret; 345 } 346 347 /* 348 * Only re-sign PAC if we could verify it with the PAC 349 * function. The no-verify case happens when we get in 350 * a PAC from cross realm from a Windows domain and 351 * that there is no PAC verification function. 352 */ 353 if (signed_pac) { 354 *signedpath = 1; 355 ret = _krb5_pac_sign(context, pac, tkt->authtime, 356 client_principal, 357 server_sign_key, krbtgt_sign_key, rspac); 358 } 359 krb5_pac_free(context, pac); 360 361 return ret; 362 } 363 } 364 free_AuthorizationData(&child); 365 } 366 return 0; 367 } 368 369 /* 370 * 371 */ 372 373 static krb5_error_code 374 check_tgs_flags(krb5_context context, 375 krb5_kdc_configuration *config, 376 KDC_REQ_BODY *b, const EncTicketPart *tgt, EncTicketPart *et) 377 { 378 KDCOptions f = b->kdc_options; 379 380 if(f.validate){ 381 if(!tgt->flags.invalid || tgt->starttime == NULL){ 382 kdc_log(context, config, 0, 383 "Bad request to validate ticket"); 384 return KRB5KDC_ERR_BADOPTION; 385 } 386 if(*tgt->starttime > kdc_time){ 387 kdc_log(context, config, 0, 388 "Early request to validate ticket"); 389 return KRB5KRB_AP_ERR_TKT_NYV; 390 } 391 /* XXX tkt = tgt */ 392 et->flags.invalid = 0; 393 }else if(tgt->flags.invalid){ 394 kdc_log(context, config, 0, 395 "Ticket-granting ticket has INVALID flag set"); 396 return KRB5KRB_AP_ERR_TKT_INVALID; 397 } 398 399 if(f.forwardable){ 400 if(!tgt->flags.forwardable){ 401 kdc_log(context, config, 0, 402 "Bad request for forwardable ticket"); 403 return KRB5KDC_ERR_BADOPTION; 404 } 405 et->flags.forwardable = 1; 406 } 407 if(f.forwarded){ 408 if(!tgt->flags.forwardable){ 409 kdc_log(context, config, 0, 410 "Request to forward non-forwardable ticket"); 411 return KRB5KDC_ERR_BADOPTION; 412 } 413 et->flags.forwarded = 1; 414 et->caddr = b->addresses; 415 } 416 if(tgt->flags.forwarded) 417 et->flags.forwarded = 1; 418 419 if(f.proxiable){ 420 if(!tgt->flags.proxiable){ 421 kdc_log(context, config, 0, 422 "Bad request for proxiable ticket"); 423 return KRB5KDC_ERR_BADOPTION; 424 } 425 et->flags.proxiable = 1; 426 } 427 if(f.proxy){ 428 if(!tgt->flags.proxiable){ 429 kdc_log(context, config, 0, 430 "Request to proxy non-proxiable ticket"); 431 return KRB5KDC_ERR_BADOPTION; 432 } 433 et->flags.proxy = 1; 434 et->caddr = b->addresses; 435 } 436 if(tgt->flags.proxy) 437 et->flags.proxy = 1; 438 439 if(f.allow_postdate){ 440 if(!tgt->flags.may_postdate){ 441 kdc_log(context, config, 0, 442 "Bad request for post-datable ticket"); 443 return KRB5KDC_ERR_BADOPTION; 444 } 445 et->flags.may_postdate = 1; 446 } 447 if(f.postdated){ 448 if(!tgt->flags.may_postdate){ 449 kdc_log(context, config, 0, 450 "Bad request for postdated ticket"); 451 return KRB5KDC_ERR_BADOPTION; 452 } 453 if(b->from) 454 *et->starttime = *b->from; 455 et->flags.postdated = 1; 456 et->flags.invalid = 1; 457 }else if(b->from && *b->from > kdc_time + context->max_skew){ 458 kdc_log(context, config, 0, "Ticket cannot be postdated"); 459 return KRB5KDC_ERR_CANNOT_POSTDATE; 460 } 461 462 if(f.renewable){ 463 if(!tgt->flags.renewable || tgt->renew_till == NULL){ 464 kdc_log(context, config, 0, 465 "Bad request for renewable ticket"); 466 return KRB5KDC_ERR_BADOPTION; 467 } 468 et->flags.renewable = 1; 469 ALLOC(et->renew_till); 470 _kdc_fix_time(&b->rtime); 471 *et->renew_till = *b->rtime; 472 } 473 if(f.renew){ 474 time_t old_life; 475 if(!tgt->flags.renewable || tgt->renew_till == NULL){ 476 kdc_log(context, config, 0, 477 "Request to renew non-renewable ticket"); 478 return KRB5KDC_ERR_BADOPTION; 479 } 480 old_life = tgt->endtime; 481 if(tgt->starttime) 482 old_life -= *tgt->starttime; 483 else 484 old_life -= tgt->authtime; 485 et->endtime = *et->starttime + old_life; 486 if (et->renew_till != NULL) 487 et->endtime = min(*et->renew_till, et->endtime); 488 } 489 490 #if 0 491 /* checks for excess flags */ 492 if(f.request_anonymous && !config->allow_anonymous){ 493 kdc_log(context, config, 0, 494 "Request for anonymous ticket"); 495 return KRB5KDC_ERR_BADOPTION; 496 } 497 #endif 498 return 0; 499 } 500 501 /* 502 * Determine if constrained delegation is allowed from this client to this server 503 */ 504 505 static krb5_error_code 506 check_constrained_delegation(krb5_context context, 507 krb5_kdc_configuration *config, 508 HDB *clientdb, 509 hdb_entry_ex *client, 510 hdb_entry_ex *server, 511 krb5_const_principal target) 512 { 513 const HDB_Ext_Constrained_delegation_acl *acl; 514 krb5_error_code ret; 515 size_t i; 516 517 /* 518 * constrained_delegation (S4U2Proxy) only works within 519 * the same realm. We use the already canonicalized version 520 * of the principals here, while "target" is the principal 521 * provided by the client. 522 */ 523 if(!krb5_realm_compare(context, client->entry.principal, server->entry.principal)) { 524 ret = KRB5KDC_ERR_BADOPTION; 525 kdc_log(context, config, 0, 526 "Bad request for constrained delegation"); 527 return ret; 528 } 529 530 if (clientdb->hdb_check_constrained_delegation) { 531 ret = clientdb->hdb_check_constrained_delegation(context, clientdb, client, target); 532 if (ret == 0) 533 return 0; 534 } else { 535 /* if client delegates to itself, that ok */ 536 if (krb5_principal_compare(context, client->entry.principal, server->entry.principal) == TRUE) 537 return 0; 538 539 ret = hdb_entry_get_ConstrainedDelegACL(&client->entry, &acl); 540 if (ret) { 541 krb5_clear_error_message(context); 542 return ret; 543 } 544 545 if (acl) { 546 for (i = 0; i < acl->len; i++) { 547 if (krb5_principal_compare(context, target, &acl->val[i]) == TRUE) 548 return 0; 549 } 550 } 551 ret = KRB5KDC_ERR_BADOPTION; 552 } 553 kdc_log(context, config, 0, 554 "Bad request for constrained delegation"); 555 return ret; 556 } 557 558 /* 559 * Determine if s4u2self is allowed from this client to this server 560 * 561 * For example, regardless of the principal being impersonated, if the 562 * 'client' and 'server' are the same, then it's safe. 563 */ 564 565 static krb5_error_code 566 check_s4u2self(krb5_context context, 567 krb5_kdc_configuration *config, 568 HDB *clientdb, 569 hdb_entry_ex *client, 570 krb5_const_principal server) 571 { 572 krb5_error_code ret; 573 574 /* if client does a s4u2self to itself, that ok */ 575 if (krb5_principal_compare(context, client->entry.principal, server) == TRUE) 576 return 0; 577 578 if (clientdb->hdb_check_s4u2self) { 579 ret = clientdb->hdb_check_s4u2self(context, clientdb, client, server); 580 if (ret == 0) 581 return 0; 582 } else { 583 ret = KRB5KDC_ERR_BADOPTION; 584 } 585 return ret; 586 } 587 588 /* 589 * 590 */ 591 592 static krb5_error_code 593 verify_flags (krb5_context context, 594 krb5_kdc_configuration *config, 595 const EncTicketPart *et, 596 const char *pstr) 597 { 598 if(et->endtime < kdc_time){ 599 kdc_log(context, config, 0, "Ticket expired (%s)", pstr); 600 return KRB5KRB_AP_ERR_TKT_EXPIRED; 601 } 602 if(et->flags.invalid){ 603 kdc_log(context, config, 0, "Ticket not valid (%s)", pstr); 604 return KRB5KRB_AP_ERR_TKT_NYV; 605 } 606 return 0; 607 } 608 609 /* 610 * 611 */ 612 613 static krb5_error_code 614 fix_transited_encoding(krb5_context context, 615 krb5_kdc_configuration *config, 616 krb5_boolean check_policy, 617 const TransitedEncoding *tr, 618 EncTicketPart *et, 619 const char *client_realm, 620 const char *server_realm, 621 const char *tgt_realm) 622 { 623 krb5_error_code ret = 0; 624 char **realms, **tmp; 625 unsigned int num_realms; 626 size_t i; 627 628 switch (tr->tr_type) { 629 case DOMAIN_X500_COMPRESS: 630 break; 631 case 0: 632 /* 633 * Allow empty content of type 0 because that is was Microsoft 634 * generates in their TGT. 635 */ 636 if (tr->contents.length == 0) 637 break; 638 kdc_log(context, config, 0, 639 "Transited type 0 with non empty content"); 640 return KRB5KDC_ERR_TRTYPE_NOSUPP; 641 default: 642 kdc_log(context, config, 0, 643 "Unknown transited type: %u", tr->tr_type); 644 return KRB5KDC_ERR_TRTYPE_NOSUPP; 645 } 646 647 ret = krb5_domain_x500_decode(context, 648 tr->contents, 649 &realms, 650 &num_realms, 651 client_realm, 652 server_realm); 653 if(ret){ 654 krb5_warn(context, ret, 655 "Decoding transited encoding"); 656 return ret; 657 } 658 if(strcmp(client_realm, tgt_realm) && strcmp(server_realm, tgt_realm)) { 659 /* not us, so add the previous realm to transited set */ 660 if (num_realms + 1 > UINT_MAX/sizeof(*realms)) { 661 ret = ERANGE; 662 goto free_realms; 663 } 664 tmp = realloc(realms, (num_realms + 1) * sizeof(*realms)); 665 if(tmp == NULL){ 666 ret = ENOMEM; 667 goto free_realms; 668 } 669 realms = tmp; 670 realms[num_realms] = strdup(tgt_realm); 671 if(realms[num_realms] == NULL){ 672 ret = ENOMEM; 673 goto free_realms; 674 } 675 num_realms++; 676 } 677 if(num_realms == 0) { 678 if(strcmp(client_realm, server_realm)) 679 kdc_log(context, config, 0, 680 "cross-realm %s -> %s", client_realm, server_realm); 681 } else { 682 size_t l = 0; 683 char *rs; 684 for(i = 0; i < num_realms; i++) 685 l += strlen(realms[i]) + 2; 686 rs = malloc(l); 687 if(rs != NULL) { 688 *rs = '\0'; 689 for(i = 0; i < num_realms; i++) { 690 if(i > 0) 691 strlcat(rs, ", ", l); 692 strlcat(rs, realms[i], l); 693 } 694 kdc_log(context, config, 0, 695 "cross-realm %s -> %s via [%s]", 696 client_realm, server_realm, rs); 697 free(rs); 698 } 699 } 700 if(check_policy) { 701 ret = krb5_check_transited(context, client_realm, 702 server_realm, 703 realms, num_realms, NULL); 704 if(ret) { 705 krb5_warn(context, ret, "cross-realm %s -> %s", 706 client_realm, server_realm); 707 goto free_realms; 708 } 709 et->flags.transited_policy_checked = 1; 710 } 711 et->transited.tr_type = DOMAIN_X500_COMPRESS; 712 ret = krb5_domain_x500_encode(realms, num_realms, &et->transited.contents); 713 if(ret) 714 krb5_warn(context, ret, "Encoding transited encoding"); 715 free_realms: 716 for(i = 0; i < num_realms; i++) 717 free(realms[i]); 718 free(realms); 719 return ret; 720 } 721 722 723 static krb5_error_code 724 tgs_make_reply(krb5_context context, 725 krb5_kdc_configuration *config, 726 KDC_REQ_BODY *b, 727 krb5_const_principal tgt_name, 728 const EncTicketPart *tgt, 729 const krb5_keyblock *replykey, 730 int rk_is_subkey, 731 const EncryptionKey *serverkey, 732 const krb5_keyblock *sessionkey, 733 krb5_kvno kvno, 734 AuthorizationData *auth_data, 735 hdb_entry_ex *server, 736 krb5_principal server_principal, 737 const char *server_name, 738 hdb_entry_ex *client, 739 krb5_principal client_principal, 740 hdb_entry_ex *krbtgt, 741 krb5_enctype krbtgt_etype, 742 krb5_principals spp, 743 const krb5_data *rspac, 744 const METHOD_DATA *enc_pa_data, 745 const char **e_text, 746 krb5_data *reply) 747 { 748 KDC_REP rep; 749 EncKDCRepPart ek; 750 EncTicketPart et; 751 KDCOptions f = b->kdc_options; 752 krb5_error_code ret; 753 int is_weak = 0; 754 755 memset(&rep, 0, sizeof(rep)); 756 memset(&et, 0, sizeof(et)); 757 memset(&ek, 0, sizeof(ek)); 758 759 rep.pvno = 5; 760 rep.msg_type = krb_tgs_rep; 761 762 et.authtime = tgt->authtime; 763 _kdc_fix_time(&b->till); 764 et.endtime = min(tgt->endtime, *b->till); 765 ALLOC(et.starttime); 766 *et.starttime = kdc_time; 767 768 ret = check_tgs_flags(context, config, b, tgt, &et); 769 if(ret) 770 goto out; 771 772 /* We should check the transited encoding if: 773 1) the request doesn't ask not to be checked 774 2) globally enforcing a check 775 3) principal requires checking 776 4) we allow non-check per-principal, but principal isn't marked as allowing this 777 5) we don't globally allow this 778 */ 779 780 #define GLOBAL_FORCE_TRANSITED_CHECK \ 781 (config->trpolicy == TRPOLICY_ALWAYS_CHECK) 782 #define GLOBAL_ALLOW_PER_PRINCIPAL \ 783 (config->trpolicy == TRPOLICY_ALLOW_PER_PRINCIPAL) 784 #define GLOBAL_ALLOW_DISABLE_TRANSITED_CHECK \ 785 (config->trpolicy == TRPOLICY_ALWAYS_HONOUR_REQUEST) 786 787 /* these will consult the database in future release */ 788 #define PRINCIPAL_FORCE_TRANSITED_CHECK(P) 0 789 #define PRINCIPAL_ALLOW_DISABLE_TRANSITED_CHECK(P) 0 790 791 ret = fix_transited_encoding(context, config, 792 !f.disable_transited_check || 793 GLOBAL_FORCE_TRANSITED_CHECK || 794 PRINCIPAL_FORCE_TRANSITED_CHECK(server) || 795 !((GLOBAL_ALLOW_PER_PRINCIPAL && 796 PRINCIPAL_ALLOW_DISABLE_TRANSITED_CHECK(server)) || 797 GLOBAL_ALLOW_DISABLE_TRANSITED_CHECK), 798 &tgt->transited, &et, 799 krb5_principal_get_realm(context, client_principal), 800 krb5_principal_get_realm(context, server->entry.principal), 801 krb5_principal_get_realm(context, krbtgt->entry.principal)); 802 if(ret) 803 goto out; 804 805 copy_Realm(&server_principal->realm, &rep.ticket.realm); 806 _krb5_principal2principalname(&rep.ticket.sname, server_principal); 807 copy_Realm(&tgt_name->realm, &rep.crealm); 808 /* 809 if (f.request_anonymous) 810 _kdc_make_anonymous_principalname (&rep.cname); 811 else */ 812 813 copy_PrincipalName(&tgt_name->name, &rep.cname); 814 rep.ticket.tkt_vno = 5; 815 816 ek.caddr = et.caddr; 817 if(et.caddr == NULL) 818 et.caddr = tgt->caddr; 819 820 { 821 time_t life; 822 life = et.endtime - *et.starttime; 823 if(client && client->entry.max_life) 824 life = min(life, *client->entry.max_life); 825 if(server->entry.max_life) 826 life = min(life, *server->entry.max_life); 827 et.endtime = *et.starttime + life; 828 } 829 if(f.renewable_ok && tgt->flags.renewable && 830 et.renew_till == NULL && et.endtime < *b->till && 831 tgt->renew_till != NULL) 832 { 833 et.flags.renewable = 1; 834 ALLOC(et.renew_till); 835 *et.renew_till = *b->till; 836 } 837 if(et.renew_till){ 838 time_t renew; 839 renew = *et.renew_till - et.authtime; 840 if(client && client->entry.max_renew) 841 renew = min(renew, *client->entry.max_renew); 842 if(server->entry.max_renew) 843 renew = min(renew, *server->entry.max_renew); 844 *et.renew_till = et.authtime + renew; 845 } 846 847 if(et.renew_till){ 848 *et.renew_till = min(*et.renew_till, *tgt->renew_till); 849 *et.starttime = min(*et.starttime, *et.renew_till); 850 et.endtime = min(et.endtime, *et.renew_till); 851 } 852 853 *et.starttime = min(*et.starttime, et.endtime); 854 855 if(*et.starttime == et.endtime){ 856 ret = KRB5KDC_ERR_NEVER_VALID; 857 goto out; 858 } 859 if(et.renew_till && et.endtime == *et.renew_till){ 860 free(et.renew_till); 861 et.renew_till = NULL; 862 et.flags.renewable = 0; 863 } 864 865 et.flags.pre_authent = tgt->flags.pre_authent; 866 et.flags.hw_authent = tgt->flags.hw_authent; 867 et.flags.anonymous = tgt->flags.anonymous; 868 et.flags.ok_as_delegate = server->entry.flags.ok_as_delegate; 869 870 if(rspac->length) { 871 /* 872 * No not need to filter out the any PAC from the 873 * auth_data since it's signed by the KDC. 874 */ 875 ret = _kdc_tkt_add_if_relevant_ad(context, &et, 876 KRB5_AUTHDATA_WIN2K_PAC, rspac); 877 if (ret) 878 goto out; 879 } 880 881 if (auth_data) { 882 unsigned int i = 0; 883 884 /* XXX check authdata */ 885 886 if (et.authorization_data == NULL) { 887 et.authorization_data = calloc(1, sizeof(*et.authorization_data)); 888 if (et.authorization_data == NULL) { 889 ret = ENOMEM; 890 krb5_set_error_message(context, ret, "malloc: out of memory"); 891 goto out; 892 } 893 } 894 for(i = 0; i < auth_data->len ; i++) { 895 ret = add_AuthorizationData(et.authorization_data, &auth_data->val[i]); 896 if (ret) { 897 krb5_set_error_message(context, ret, "malloc: out of memory"); 898 goto out; 899 } 900 } 901 902 /* Filter out type KRB5SignedPath */ 903 ret = find_KRB5SignedPath(context, et.authorization_data, NULL); 904 if (ret == 0) { 905 if (et.authorization_data->len == 1) { 906 free_AuthorizationData(et.authorization_data); 907 free(et.authorization_data); 908 et.authorization_data = NULL; 909 } else { 910 AuthorizationData *ad = et.authorization_data; 911 free_AuthorizationDataElement(&ad->val[ad->len - 1]); 912 ad->len--; 913 } 914 } 915 } 916 917 ret = krb5_copy_keyblock_contents(context, sessionkey, &et.key); 918 if (ret) 919 goto out; 920 et.crealm = tgt_name->realm; 921 et.cname = tgt_name->name; 922 923 ek.key = et.key; 924 /* MIT must have at least one last_req */ 925 ek.last_req.len = 1; 926 ek.last_req.val = calloc(1, sizeof(*ek.last_req.val)); 927 if (ek.last_req.val == NULL) { 928 ret = ENOMEM; 929 goto out; 930 } 931 ek.nonce = b->nonce; 932 ek.flags = et.flags; 933 ek.authtime = et.authtime; 934 ek.starttime = et.starttime; 935 ek.endtime = et.endtime; 936 ek.renew_till = et.renew_till; 937 ek.srealm = rep.ticket.realm; 938 ek.sname = rep.ticket.sname; 939 940 _kdc_log_timestamp(context, config, "TGS-REQ", et.authtime, et.starttime, 941 et.endtime, et.renew_till); 942 943 /* Don't sign cross realm tickets, they can't be checked anyway */ 944 { 945 char *r = get_krbtgt_realm(&ek.sname); 946 947 if (r == NULL || strcmp(r, ek.srealm) == 0) { 948 ret = _kdc_add_KRB5SignedPath(context, 949 config, 950 krbtgt, 951 krbtgt_etype, 952 client_principal, 953 NULL, 954 spp, 955 &et); 956 if (ret) 957 goto out; 958 } 959 } 960 961 if (enc_pa_data->len) { 962 rep.padata = calloc(1, sizeof(*rep.padata)); 963 if (rep.padata == NULL) { 964 ret = ENOMEM; 965 goto out; 966 } 967 ret = copy_METHOD_DATA(enc_pa_data, rep.padata); 968 if (ret) 969 goto out; 970 } 971 972 if (krb5_enctype_valid(context, et.key.keytype) != 0 973 && _kdc_is_weak_exception(server->entry.principal, et.key.keytype)) 974 { 975 krb5_enctype_enable(context, et.key.keytype); 976 is_weak = 1; 977 } 978 979 980 /* It is somewhat unclear where the etype in the following 981 encryption should come from. What we have is a session 982 key in the passed tgt, and a list of preferred etypes 983 *for the new ticket*. Should we pick the best possible 984 etype, given the keytype in the tgt, or should we look 985 at the etype list here as well? What if the tgt 986 session key is DES3 and we want a ticket with a (say) 987 CAST session key. Should the DES3 etype be added to the 988 etype list, even if we don't want a session key with 989 DES3? */ 990 ret = _kdc_encode_reply(context, config, 991 &rep, &et, &ek, et.key.keytype, 992 kvno, 993 serverkey, 0, replykey, rk_is_subkey, 994 e_text, reply); 995 if (is_weak) 996 krb5_enctype_disable(context, et.key.keytype); 997 998 out: 999 free_TGS_REP(&rep); 1000 free_TransitedEncoding(&et.transited); 1001 if(et.starttime) 1002 free(et.starttime); 1003 if(et.renew_till) 1004 free(et.renew_till); 1005 if(et.authorization_data) { 1006 free_AuthorizationData(et.authorization_data); 1007 free(et.authorization_data); 1008 } 1009 free_LastReq(&ek.last_req); 1010 memset(et.key.keyvalue.data, 0, et.key.keyvalue.length); 1011 free_EncryptionKey(&et.key); 1012 return ret; 1013 } 1014 1015 static krb5_error_code 1016 tgs_check_authenticator(krb5_context context, 1017 krb5_kdc_configuration *config, 1018 krb5_auth_context ac, 1019 KDC_REQ_BODY *b, 1020 const char **e_text, 1021 krb5_keyblock *key) 1022 { 1023 krb5_authenticator auth; 1024 size_t len = 0; 1025 unsigned char *buf; 1026 size_t buf_size; 1027 krb5_error_code ret; 1028 krb5_crypto crypto; 1029 1030 krb5_auth_con_getauthenticator(context, ac, &auth); 1031 if(auth->cksum == NULL){ 1032 kdc_log(context, config, 0, "No authenticator in request"); 1033 ret = KRB5KRB_AP_ERR_INAPP_CKSUM; 1034 goto out; 1035 } 1036 /* 1037 * according to RFC1510 it doesn't need to be keyed, 1038 * but according to the latest draft it needs to. 1039 */ 1040 if ( 1041 #if 0 1042 !krb5_checksum_is_keyed(context, auth->cksum->cksumtype) 1043 || 1044 #endif 1045 !krb5_checksum_is_collision_proof(context, auth->cksum->cksumtype)) { 1046 kdc_log(context, config, 0, "Bad checksum type in authenticator: %d", 1047 auth->cksum->cksumtype); 1048 ret = KRB5KRB_AP_ERR_INAPP_CKSUM; 1049 goto out; 1050 } 1051 1052 /* XXX should not re-encode this */ 1053 ASN1_MALLOC_ENCODE(KDC_REQ_BODY, buf, buf_size, b, &len, ret); 1054 if(ret){ 1055 const char *msg = krb5_get_error_message(context, ret); 1056 kdc_log(context, config, 0, "Failed to encode KDC-REQ-BODY: %s", msg); 1057 krb5_free_error_message(context, msg); 1058 goto out; 1059 } 1060 if(buf_size != len) { 1061 free(buf); 1062 kdc_log(context, config, 0, "Internal error in ASN.1 encoder"); 1063 *e_text = "KDC internal error"; 1064 ret = KRB5KRB_ERR_GENERIC; 1065 goto out; 1066 } 1067 ret = krb5_crypto_init(context, key, 0, &crypto); 1068 if (ret) { 1069 const char *msg = krb5_get_error_message(context, ret); 1070 free(buf); 1071 kdc_log(context, config, 0, "krb5_crypto_init failed: %s", msg); 1072 krb5_free_error_message(context, msg); 1073 goto out; 1074 } 1075 ret = krb5_verify_checksum(context, 1076 crypto, 1077 KRB5_KU_TGS_REQ_AUTH_CKSUM, 1078 buf, 1079 len, 1080 auth->cksum); 1081 free(buf); 1082 krb5_crypto_destroy(context, crypto); 1083 if(ret){ 1084 const char *msg = krb5_get_error_message(context, ret); 1085 kdc_log(context, config, 0, 1086 "Failed to verify authenticator checksum: %s", msg); 1087 krb5_free_error_message(context, msg); 1088 } 1089 out: 1090 free_Authenticator(auth); 1091 free(auth); 1092 return ret; 1093 } 1094 1095 /* 1096 * 1097 */ 1098 1099 static const char * 1100 find_rpath(krb5_context context, Realm crealm, Realm srealm) 1101 { 1102 const char *new_realm = krb5_config_get_string(context, 1103 NULL, 1104 "capaths", 1105 crealm, 1106 srealm, 1107 NULL); 1108 return new_realm; 1109 } 1110 1111 1112 static krb5_boolean 1113 need_referral(krb5_context context, krb5_kdc_configuration *config, 1114 const KDCOptions * const options, krb5_principal server, 1115 krb5_realm **realms) 1116 { 1117 const char *name; 1118 1119 if(!options->canonicalize && server->name.name_type != KRB5_NT_SRV_INST) 1120 return FALSE; 1121 1122 if (server->name.name_string.len == 1) 1123 name = server->name.name_string.val[0]; 1124 else if (server->name.name_string.len > 1) 1125 name = server->name.name_string.val[1]; 1126 else 1127 return FALSE; 1128 1129 kdc_log(context, config, 0, "Searching referral for %s", name); 1130 1131 return _krb5_get_host_realm_int(context, name, FALSE, realms) == 0; 1132 } 1133 1134 static krb5_error_code 1135 tgs_parse_request(krb5_context context, 1136 krb5_kdc_configuration *config, 1137 KDC_REQ_BODY *b, 1138 const PA_DATA *tgs_req, 1139 hdb_entry_ex **krbtgt, 1140 krb5_enctype *krbtgt_etype, 1141 krb5_ticket **ticket, 1142 const char **e_text, 1143 const char *from, 1144 const struct sockaddr *from_addr, 1145 time_t **csec, 1146 int **cusec, 1147 AuthorizationData **auth_data, 1148 krb5_keyblock **replykey, 1149 int *rk_is_subkey) 1150 { 1151 static char failed[] = "<unparse_name failed>"; 1152 krb5_ap_req ap_req; 1153 krb5_error_code ret; 1154 krb5_principal princ; 1155 krb5_auth_context ac = NULL; 1156 krb5_flags ap_req_options; 1157 krb5_flags verify_ap_req_flags; 1158 krb5_crypto crypto; 1159 Key *tkey; 1160 krb5_keyblock *subkey = NULL; 1161 unsigned usage; 1162 1163 *auth_data = NULL; 1164 *csec = NULL; 1165 *cusec = NULL; 1166 *replykey = NULL; 1167 1168 memset(&ap_req, 0, sizeof(ap_req)); 1169 ret = krb5_decode_ap_req(context, &tgs_req->padata_value, &ap_req); 1170 if(ret){ 1171 const char *msg = krb5_get_error_message(context, ret); 1172 kdc_log(context, config, 0, "Failed to decode AP-REQ: %s", msg); 1173 krb5_free_error_message(context, msg); 1174 goto out; 1175 } 1176 1177 if(!get_krbtgt_realm(&ap_req.ticket.sname)){ 1178 /* XXX check for ticket.sname == req.sname */ 1179 kdc_log(context, config, 0, "PA-DATA is not a ticket-granting ticket"); 1180 ret = KRB5KDC_ERR_POLICY; /* ? */ 1181 goto out; 1182 } 1183 1184 _krb5_principalname2krb5_principal(context, 1185 &princ, 1186 ap_req.ticket.sname, 1187 ap_req.ticket.realm); 1188 1189 ret = _kdc_db_fetch(context, config, princ, HDB_F_GET_KRBTGT, ap_req.ticket.enc_part.kvno, NULL, krbtgt); 1190 1191 if(ret == HDB_ERR_NOT_FOUND_HERE) { 1192 char *p; 1193 ret = krb5_unparse_name(context, princ, &p); 1194 if (ret != 0) 1195 p = failed; 1196 krb5_free_principal(context, princ); 1197 kdc_log(context, config, 5, "Ticket-granting ticket account %s does not have secrets at this KDC, need to proxy", p); 1198 if (ret == 0) 1199 free(p); 1200 ret = HDB_ERR_NOT_FOUND_HERE; 1201 goto out; 1202 } else if(ret){ 1203 const char *msg = krb5_get_error_message(context, ret); 1204 char *p; 1205 ret = krb5_unparse_name(context, princ, &p); 1206 if (ret != 0) 1207 p = failed; 1208 krb5_free_principal(context, princ); 1209 kdc_log(context, config, 0, 1210 "Ticket-granting ticket not found in database: %s", msg); 1211 krb5_free_error_message(context, msg); 1212 if (ret == 0) 1213 free(p); 1214 ret = KRB5KRB_AP_ERR_NOT_US; 1215 goto out; 1216 } 1217 1218 if(ap_req.ticket.enc_part.kvno && 1219 *ap_req.ticket.enc_part.kvno != (*krbtgt)->entry.kvno){ 1220 char *p; 1221 1222 ret = krb5_unparse_name (context, princ, &p); 1223 krb5_free_principal(context, princ); 1224 if (ret != 0) 1225 p = failed; 1226 kdc_log(context, config, 0, 1227 "Ticket kvno = %d, DB kvno = %d (%s)", 1228 *ap_req.ticket.enc_part.kvno, 1229 (*krbtgt)->entry.kvno, 1230 p); 1231 if (ret == 0) 1232 free (p); 1233 ret = KRB5KRB_AP_ERR_BADKEYVER; 1234 goto out; 1235 } 1236 1237 *krbtgt_etype = ap_req.ticket.enc_part.etype; 1238 1239 ret = hdb_enctype2key(context, &(*krbtgt)->entry, 1240 ap_req.ticket.enc_part.etype, &tkey); 1241 if(ret){ 1242 char *str = NULL, *p = NULL; 1243 1244 krb5_enctype_to_string(context, ap_req.ticket.enc_part.etype, &str); 1245 krb5_unparse_name(context, princ, &p); 1246 kdc_log(context, config, 0, 1247 "No server key with enctype %s found for %s", 1248 str ? str : "<unknown enctype>", 1249 p ? p : "<unparse_name failed>"); 1250 free(str); 1251 free(p); 1252 ret = KRB5KRB_AP_ERR_BADKEYVER; 1253 goto out; 1254 } 1255 1256 if (b->kdc_options.validate) 1257 verify_ap_req_flags = KRB5_VERIFY_AP_REQ_IGNORE_INVALID; 1258 else 1259 verify_ap_req_flags = 0; 1260 1261 ret = krb5_verify_ap_req2(context, 1262 &ac, 1263 &ap_req, 1264 princ, 1265 &tkey->key, 1266 verify_ap_req_flags, 1267 &ap_req_options, 1268 ticket, 1269 KRB5_KU_TGS_REQ_AUTH); 1270 1271 krb5_free_principal(context, princ); 1272 if(ret) { 1273 const char *msg = krb5_get_error_message(context, ret); 1274 kdc_log(context, config, 0, "Failed to verify AP-REQ: %s", msg); 1275 krb5_free_error_message(context, msg); 1276 goto out; 1277 } 1278 1279 { 1280 krb5_authenticator auth; 1281 1282 ret = krb5_auth_con_getauthenticator(context, ac, &auth); 1283 if (ret == 0) { 1284 *csec = malloc(sizeof(**csec)); 1285 if (*csec == NULL) { 1286 krb5_free_authenticator(context, &auth); 1287 kdc_log(context, config, 0, "malloc failed"); 1288 goto out; 1289 } 1290 **csec = auth->ctime; 1291 *cusec = malloc(sizeof(**cusec)); 1292 if (*cusec == NULL) { 1293 krb5_free_authenticator(context, &auth); 1294 kdc_log(context, config, 0, "malloc failed"); 1295 goto out; 1296 } 1297 **cusec = auth->cusec; 1298 krb5_free_authenticator(context, &auth); 1299 } 1300 } 1301 1302 ret = tgs_check_authenticator(context, config, 1303 ac, b, e_text, &(*ticket)->ticket.key); 1304 if (ret) { 1305 krb5_auth_con_free(context, ac); 1306 goto out; 1307 } 1308 1309 usage = KRB5_KU_TGS_REQ_AUTH_DAT_SUBKEY; 1310 *rk_is_subkey = 1; 1311 1312 ret = krb5_auth_con_getremotesubkey(context, ac, &subkey); 1313 if(ret){ 1314 const char *msg = krb5_get_error_message(context, ret); 1315 krb5_auth_con_free(context, ac); 1316 kdc_log(context, config, 0, "Failed to get remote subkey: %s", msg); 1317 krb5_free_error_message(context, msg); 1318 goto out; 1319 } 1320 if(subkey == NULL){ 1321 usage = KRB5_KU_TGS_REQ_AUTH_DAT_SESSION; 1322 *rk_is_subkey = 0; 1323 1324 ret = krb5_auth_con_getkey(context, ac, &subkey); 1325 if(ret) { 1326 const char *msg = krb5_get_error_message(context, ret); 1327 krb5_auth_con_free(context, ac); 1328 kdc_log(context, config, 0, "Failed to get session key: %s", msg); 1329 krb5_free_error_message(context, msg); 1330 goto out; 1331 } 1332 } 1333 if(subkey == NULL){ 1334 krb5_auth_con_free(context, ac); 1335 kdc_log(context, config, 0, 1336 "Failed to get key for enc-authorization-data"); 1337 ret = KRB5KRB_AP_ERR_BAD_INTEGRITY; /* ? */ 1338 goto out; 1339 } 1340 1341 *replykey = subkey; 1342 1343 if (b->enc_authorization_data) { 1344 krb5_data ad; 1345 1346 ret = krb5_crypto_init(context, subkey, 0, &crypto); 1347 if (ret) { 1348 const char *msg = krb5_get_error_message(context, ret); 1349 krb5_auth_con_free(context, ac); 1350 kdc_log(context, config, 0, "krb5_crypto_init failed: %s", msg); 1351 krb5_free_error_message(context, msg); 1352 goto out; 1353 } 1354 ret = krb5_decrypt_EncryptedData (context, 1355 crypto, 1356 usage, 1357 b->enc_authorization_data, 1358 &ad); 1359 krb5_crypto_destroy(context, crypto); 1360 if(ret){ 1361 krb5_auth_con_free(context, ac); 1362 kdc_log(context, config, 0, 1363 "Failed to decrypt enc-authorization-data"); 1364 ret = KRB5KRB_AP_ERR_BAD_INTEGRITY; /* ? */ 1365 goto out; 1366 } 1367 ALLOC(*auth_data); 1368 if (*auth_data == NULL) { 1369 krb5_auth_con_free(context, ac); 1370 ret = KRB5KRB_AP_ERR_BAD_INTEGRITY; /* ? */ 1371 goto out; 1372 } 1373 ret = decode_AuthorizationData(ad.data, ad.length, *auth_data, NULL); 1374 if(ret){ 1375 krb5_auth_con_free(context, ac); 1376 free(*auth_data); 1377 *auth_data = NULL; 1378 kdc_log(context, config, 0, "Failed to decode authorization data"); 1379 ret = KRB5KRB_AP_ERR_BAD_INTEGRITY; /* ? */ 1380 goto out; 1381 } 1382 } 1383 1384 krb5_auth_con_free(context, ac); 1385 1386 out: 1387 free_AP_REQ(&ap_req); 1388 1389 return ret; 1390 } 1391 1392 static krb5_error_code 1393 build_server_referral(krb5_context context, 1394 krb5_kdc_configuration *config, 1395 krb5_crypto session, 1396 krb5_const_realm referred_realm, 1397 const PrincipalName *true_principal_name, 1398 const PrincipalName *requested_principal, 1399 krb5_data *outdata) 1400 { 1401 PA_ServerReferralData ref; 1402 krb5_error_code ret; 1403 EncryptedData ed; 1404 krb5_data data; 1405 size_t size = 0; 1406 1407 memset(&ref, 0, sizeof(ref)); 1408 1409 if (referred_realm) { 1410 ALLOC(ref.referred_realm); 1411 if (ref.referred_realm == NULL) 1412 goto eout; 1413 *ref.referred_realm = strdup(referred_realm); 1414 if (*ref.referred_realm == NULL) 1415 goto eout; 1416 } 1417 if (true_principal_name) { 1418 ALLOC(ref.true_principal_name); 1419 if (ref.true_principal_name == NULL) 1420 goto eout; 1421 ret = copy_PrincipalName(true_principal_name, ref.true_principal_name); 1422 if (ret) 1423 goto eout; 1424 } 1425 if (requested_principal) { 1426 ALLOC(ref.requested_principal_name); 1427 if (ref.requested_principal_name == NULL) 1428 goto eout; 1429 ret = copy_PrincipalName(requested_principal, 1430 ref.requested_principal_name); 1431 if (ret) 1432 goto eout; 1433 } 1434 1435 ASN1_MALLOC_ENCODE(PA_ServerReferralData, 1436 data.data, data.length, 1437 &ref, &size, ret); 1438 free_PA_ServerReferralData(&ref); 1439 if (ret) 1440 return ret; 1441 if (data.length != size) 1442 krb5_abortx(context, "internal asn.1 encoder error"); 1443 1444 ret = krb5_encrypt_EncryptedData(context, session, 1445 KRB5_KU_PA_SERVER_REFERRAL, 1446 data.data, data.length, 1447 0 /* kvno */, &ed); 1448 free(data.data); 1449 if (ret) 1450 return ret; 1451 1452 ASN1_MALLOC_ENCODE(EncryptedData, 1453 outdata->data, outdata->length, 1454 &ed, &size, ret); 1455 free_EncryptedData(&ed); 1456 if (ret) 1457 return ret; 1458 if (outdata->length != size) 1459 krb5_abortx(context, "internal asn.1 encoder error"); 1460 1461 return 0; 1462 eout: 1463 free_PA_ServerReferralData(&ref); 1464 krb5_set_error_message(context, ENOMEM, "malloc: out of memory"); 1465 return ENOMEM; 1466 } 1467 1468 static krb5_error_code 1469 tgs_build_reply(krb5_context context, 1470 krb5_kdc_configuration *config, 1471 KDC_REQ *req, 1472 KDC_REQ_BODY *b, 1473 hdb_entry_ex *krbtgt, 1474 krb5_enctype krbtgt_etype, 1475 const krb5_keyblock *replykey, 1476 int rk_is_subkey, 1477 krb5_ticket *ticket, 1478 krb5_data *reply, 1479 const char *from, 1480 const char **e_text, 1481 AuthorizationData **auth_data, 1482 const struct sockaddr *from_addr) 1483 { 1484 krb5_error_code ret; 1485 krb5_principal cp = NULL, sp = NULL, rsp = NULL, tp = NULL, dp = NULL; 1486 krb5_principal krbtgt_principal = NULL; 1487 char *spn = NULL, *cpn = NULL, *tpn = NULL, *dpn = NULL; 1488 hdb_entry_ex *server = NULL, *client = NULL, *s4u2self_impersonated_client = NULL; 1489 HDB *clientdb, *s4u2self_impersonated_clientdb; 1490 krb5_realm ref_realm = NULL; 1491 EncTicketPart *tgt = &ticket->ticket; 1492 krb5_principals spp = NULL; 1493 const EncryptionKey *ekey; 1494 krb5_keyblock sessionkey; 1495 krb5_kvno kvno; 1496 krb5_data rspac; 1497 1498 hdb_entry_ex *krbtgt_out = NULL; 1499 1500 METHOD_DATA enc_pa_data; 1501 1502 PrincipalName *s; 1503 Realm r; 1504 int nloop = 0; 1505 EncTicketPart adtkt; 1506 char opt_str[128]; 1507 int signedpath = 0; 1508 1509 Key *tkey_check; 1510 Key *tkey_sign; 1511 int flags = HDB_F_FOR_TGS_REQ; 1512 1513 memset(&sessionkey, 0, sizeof(sessionkey)); 1514 memset(&adtkt, 0, sizeof(adtkt)); 1515 krb5_data_zero(&rspac); 1516 memset(&enc_pa_data, 0, sizeof(enc_pa_data)); 1517 1518 s = b->sname; 1519 r = b->realm; 1520 1521 /* 1522 * Always to do CANON, see comment below about returned server principal (rsp). 1523 */ 1524 flags |= HDB_F_CANON; 1525 1526 if(b->kdc_options.enc_tkt_in_skey){ 1527 Ticket *t; 1528 hdb_entry_ex *uu; 1529 krb5_principal p; 1530 Key *uukey; 1531 1532 if(b->additional_tickets == NULL || 1533 b->additional_tickets->len == 0){ 1534 ret = KRB5KDC_ERR_BADOPTION; /* ? */ 1535 kdc_log(context, config, 0, 1536 "No second ticket present in request"); 1537 goto out; 1538 } 1539 t = &b->additional_tickets->val[0]; 1540 if(!get_krbtgt_realm(&t->sname)){ 1541 kdc_log(context, config, 0, 1542 "Additional ticket is not a ticket-granting ticket"); 1543 ret = KRB5KDC_ERR_POLICY; 1544 goto out; 1545 } 1546 _krb5_principalname2krb5_principal(context, &p, t->sname, t->realm); 1547 ret = _kdc_db_fetch(context, config, p, 1548 HDB_F_GET_KRBTGT, t->enc_part.kvno, 1549 NULL, &uu); 1550 krb5_free_principal(context, p); 1551 if(ret){ 1552 if (ret == HDB_ERR_NOENTRY) 1553 ret = KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN; 1554 goto out; 1555 } 1556 ret = hdb_enctype2key(context, &uu->entry, 1557 t->enc_part.etype, &uukey); 1558 if(ret){ 1559 _kdc_free_ent(context, uu); 1560 ret = KRB5KDC_ERR_ETYPE_NOSUPP; /* XXX */ 1561 goto out; 1562 } 1563 ret = krb5_decrypt_ticket(context, t, &uukey->key, &adtkt, 0); 1564 _kdc_free_ent(context, uu); 1565 if(ret) 1566 goto out; 1567 1568 ret = verify_flags(context, config, &adtkt, spn); 1569 if (ret) 1570 goto out; 1571 1572 s = &adtkt.cname; 1573 r = adtkt.crealm; 1574 } 1575 1576 _krb5_principalname2krb5_principal(context, &sp, *s, r); 1577 ret = krb5_unparse_name(context, sp, &spn); 1578 if (ret) 1579 goto out; 1580 _krb5_principalname2krb5_principal(context, &cp, tgt->cname, tgt->crealm); 1581 ret = krb5_unparse_name(context, cp, &cpn); 1582 if (ret) 1583 goto out; 1584 unparse_flags (KDCOptions2int(b->kdc_options), 1585 asn1_KDCOptions_units(), 1586 opt_str, sizeof(opt_str)); 1587 if(*opt_str) 1588 kdc_log(context, config, 0, 1589 "TGS-REQ %s from %s for %s [%s]", 1590 cpn, from, spn, opt_str); 1591 else 1592 kdc_log(context, config, 0, 1593 "TGS-REQ %s from %s for %s", cpn, from, spn); 1594 1595 /* 1596 * Fetch server 1597 */ 1598 1599 server_lookup: 1600 ret = _kdc_db_fetch(context, config, sp, HDB_F_GET_SERVER | flags, 1601 NULL, NULL, &server); 1602 1603 if(ret == HDB_ERR_NOT_FOUND_HERE) { 1604 kdc_log(context, config, 5, "target %s does not have secrets at this KDC, need to proxy", sp); 1605 goto out; 1606 } else if(ret){ 1607 const char *new_rlm, *msg; 1608 Realm req_rlm; 1609 krb5_realm *realms; 1610 1611 if ((req_rlm = get_krbtgt_realm(&sp->name)) != NULL) { 1612 if(nloop++ < 2) { 1613 new_rlm = find_rpath(context, tgt->crealm, req_rlm); 1614 if(new_rlm) { 1615 kdc_log(context, config, 5, "krbtgt for realm %s " 1616 "not found, trying %s", 1617 req_rlm, new_rlm); 1618 krb5_free_principal(context, sp); 1619 free(spn); 1620 krb5_make_principal(context, &sp, r, 1621 KRB5_TGS_NAME, new_rlm, NULL); 1622 ret = krb5_unparse_name(context, sp, &spn); 1623 if (ret) 1624 goto out; 1625 1626 if (ref_realm) 1627 free(ref_realm); 1628 ref_realm = strdup(new_rlm); 1629 goto server_lookup; 1630 } 1631 } 1632 } else if(need_referral(context, config, &b->kdc_options, sp, &realms)) { 1633 if (strcmp(realms[0], sp->realm) != 0) { 1634 kdc_log(context, config, 5, 1635 "Returning a referral to realm %s for " 1636 "server %s that was not found", 1637 realms[0], spn); 1638 krb5_free_principal(context, sp); 1639 free(spn); 1640 krb5_make_principal(context, &sp, r, KRB5_TGS_NAME, 1641 realms[0], NULL); 1642 ret = krb5_unparse_name(context, sp, &spn); 1643 if (ret) 1644 goto out; 1645 1646 if (ref_realm) 1647 free(ref_realm); 1648 ref_realm = strdup(realms[0]); 1649 1650 krb5_free_host_realm(context, realms); 1651 goto server_lookup; 1652 } 1653 krb5_free_host_realm(context, realms); 1654 } 1655 msg = krb5_get_error_message(context, ret); 1656 kdc_log(context, config, 0, 1657 "Server not found in database: %s: %s", spn, msg); 1658 krb5_free_error_message(context, msg); 1659 if (ret == HDB_ERR_NOENTRY) 1660 ret = KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN; 1661 goto out; 1662 } 1663 1664 /* the name returned to the client depend on what was asked for, 1665 * return canonical name if kdc_options.canonicalize was set, the 1666 * client wants the true name of the principal, if not it just 1667 * wants the name its asked for. 1668 */ 1669 1670 if (b->kdc_options.canonicalize) 1671 rsp = server->entry.principal; 1672 else 1673 rsp = sp; 1674 1675 1676 /* 1677 * Select enctype, return key and kvno. 1678 */ 1679 1680 { 1681 krb5_enctype etype; 1682 1683 if(b->kdc_options.enc_tkt_in_skey) { 1684 size_t i; 1685 ekey = &adtkt.key; 1686 for(i = 0; i < b->etype.len; i++) 1687 if (b->etype.val[i] == adtkt.key.keytype) 1688 break; 1689 if(i == b->etype.len) { 1690 kdc_log(context, config, 0, 1691 "Addition ticket have not matching etypes"); 1692 krb5_clear_error_message(context); 1693 ret = KRB5KDC_ERR_ETYPE_NOSUPP; 1694 goto out; 1695 } 1696 etype = b->etype.val[i]; 1697 kvno = 0; 1698 } else { 1699 Key *skey; 1700 1701 ret = _kdc_find_etype(context, 1702 config->tgs_use_strongest_session_key, FALSE, 1703 server, b->etype.val, b->etype.len, NULL, 1704 &skey); 1705 if(ret) { 1706 kdc_log(context, config, 0, 1707 "Server (%s) has no support for etypes", spn); 1708 goto out; 1709 } 1710 ekey = &skey->key; 1711 etype = skey->key.keytype; 1712 kvno = server->entry.kvno; 1713 } 1714 1715 ret = krb5_generate_random_keyblock(context, etype, &sessionkey); 1716 if (ret) 1717 goto out; 1718 } 1719 1720 /* 1721 * Check that service is in the same realm as the krbtgt. If it's 1722 * not the same, it's someone that is using a uni-directional trust 1723 * backward. 1724 */ 1725 1726 /* 1727 * Validate authoriation data 1728 */ 1729 1730 ret = hdb_enctype2key(context, &krbtgt->entry, 1731 krbtgt_etype, &tkey_check); 1732 if(ret) { 1733 kdc_log(context, config, 0, 1734 "Failed to find key for krbtgt PAC check"); 1735 goto out; 1736 } 1737 1738 /* Now refetch the primary krbtgt, and get the current kvno (the 1739 * sign check may have been on an old kvno, and the server may 1740 * have been an incoming trust) */ 1741 ret = krb5_make_principal(context, &krbtgt_principal, 1742 krb5_principal_get_comp_string(context, 1743 krbtgt->entry.principal, 1744 1), 1745 KRB5_TGS_NAME, 1746 krb5_principal_get_comp_string(context, 1747 krbtgt->entry.principal, 1748 1), NULL); 1749 if(ret) { 1750 kdc_log(context, config, 0, 1751 "Failed to generate krbtgt principal"); 1752 goto out; 1753 } 1754 1755 ret = _kdc_db_fetch(context, config, krbtgt_principal, HDB_F_GET_KRBTGT, NULL, NULL, &krbtgt_out); 1756 krb5_free_principal(context, krbtgt_principal); 1757 if (ret) { 1758 krb5_error_code ret2; 1759 char *ktpn, *ktpn2; 1760 ret = krb5_unparse_name(context, krbtgt->entry.principal, &ktpn); 1761 ret2 = krb5_unparse_name(context, krbtgt_principal, &ktpn2); 1762 kdc_log(context, config, 0, 1763 "Request with wrong krbtgt: %s, %s not found in our database", 1764 (ret == 0) ? ktpn : "<unknown>", (ret2 == 0) ? ktpn2 : "<unknown>"); 1765 if(ret == 0) 1766 free(ktpn); 1767 if(ret2 == 0) 1768 free(ktpn2); 1769 ret = KRB5KRB_AP_ERR_NOT_US; 1770 goto out; 1771 } 1772 1773 /* The first realm is the realm of the service, the second is 1774 * krbtgt/<this>/@REALM component of the krbtgt DN the request was 1775 * encrypted to. The redirection via the krbtgt_out entry allows 1776 * the DB to possibly correct the case of the realm (Samba4 does 1777 * this) before the strcmp() */ 1778 if (strcmp(krb5_principal_get_realm(context, server->entry.principal), 1779 krb5_principal_get_realm(context, krbtgt_out->entry.principal)) != 0) { 1780 char *ktpn; 1781 ret = krb5_unparse_name(context, krbtgt_out->entry.principal, &ktpn); 1782 kdc_log(context, config, 0, 1783 "Request with wrong krbtgt: %s", 1784 (ret == 0) ? ktpn : "<unknown>"); 1785 if(ret == 0) 1786 free(ktpn); 1787 ret = KRB5KRB_AP_ERR_NOT_US; 1788 } 1789 1790 ret = hdb_enctype2key(context, &krbtgt_out->entry, 1791 krbtgt_etype, &tkey_sign); 1792 if(ret) { 1793 kdc_log(context, config, 0, 1794 "Failed to find key for krbtgt PAC signature"); 1795 goto out; 1796 } 1797 1798 ret = _kdc_db_fetch(context, config, cp, HDB_F_GET_CLIENT | flags, 1799 NULL, &clientdb, &client); 1800 if(ret == HDB_ERR_NOT_FOUND_HERE) { 1801 /* This is OK, we are just trying to find out if they have 1802 * been disabled or deleted in the meantime, missing secrets 1803 * is OK */ 1804 } else if(ret){ 1805 const char *krbtgt_realm, *msg; 1806 1807 /* 1808 * If the client belongs to the same realm as our krbtgt, it 1809 * should exist in the local database. 1810 * 1811 */ 1812 1813 krbtgt_realm = krb5_principal_get_realm(context, krbtgt_out->entry.principal); 1814 1815 if(strcmp(krb5_principal_get_realm(context, cp), krbtgt_realm) == 0) { 1816 if (ret == HDB_ERR_NOENTRY) 1817 ret = KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN; 1818 kdc_log(context, config, 1, "Client no longer in database: %s", 1819 cpn); 1820 goto out; 1821 } 1822 1823 msg = krb5_get_error_message(context, ret); 1824 kdc_log(context, config, 1, "Client not found in database: %s", msg); 1825 krb5_free_error_message(context, msg); 1826 } 1827 1828 ret = check_PAC(context, config, cp, NULL, 1829 client, server, krbtgt, 1830 &tkey_check->key, &tkey_check->key, 1831 ekey, &tkey_sign->key, 1832 tgt, &rspac, &signedpath); 1833 if (ret) { 1834 const char *msg = krb5_get_error_message(context, ret); 1835 kdc_log(context, config, 0, 1836 "Verify PAC failed for %s (%s) from %s with %s", 1837 spn, cpn, from, msg); 1838 krb5_free_error_message(context, msg); 1839 goto out; 1840 } 1841 1842 /* also check the krbtgt for signature */ 1843 ret = check_KRB5SignedPath(context, 1844 config, 1845 krbtgt, 1846 cp, 1847 tgt, 1848 &spp, 1849 &signedpath); 1850 if (ret) { 1851 const char *msg = krb5_get_error_message(context, ret); 1852 kdc_log(context, config, 0, 1853 "KRB5SignedPath check failed for %s (%s) from %s with %s", 1854 spn, cpn, from, msg); 1855 krb5_free_error_message(context, msg); 1856 goto out; 1857 } 1858 1859 /* 1860 * Process request 1861 */ 1862 1863 /* by default the tgt principal matches the client principal */ 1864 tp = cp; 1865 tpn = cpn; 1866 1867 if (client) { 1868 const PA_DATA *sdata; 1869 int i = 0; 1870 1871 sdata = _kdc_find_padata(req, &i, KRB5_PADATA_FOR_USER); 1872 if (sdata) { 1873 krb5_crypto crypto; 1874 krb5_data datack; 1875 PA_S4U2Self self; 1876 const char *str; 1877 1878 ret = decode_PA_S4U2Self(sdata->padata_value.data, 1879 sdata->padata_value.length, 1880 &self, NULL); 1881 if (ret) { 1882 kdc_log(context, config, 0, "Failed to decode PA-S4U2Self"); 1883 goto out; 1884 } 1885 1886 ret = _krb5_s4u2self_to_checksumdata(context, &self, &datack); 1887 if (ret) 1888 goto out; 1889 1890 ret = krb5_crypto_init(context, &tgt->key, 0, &crypto); 1891 if (ret) { 1892 const char *msg = krb5_get_error_message(context, ret); 1893 free_PA_S4U2Self(&self); 1894 krb5_data_free(&datack); 1895 kdc_log(context, config, 0, "krb5_crypto_init failed: %s", msg); 1896 krb5_free_error_message(context, msg); 1897 goto out; 1898 } 1899 1900 ret = krb5_verify_checksum(context, 1901 crypto, 1902 KRB5_KU_OTHER_CKSUM, 1903 datack.data, 1904 datack.length, 1905 &self.cksum); 1906 krb5_data_free(&datack); 1907 krb5_crypto_destroy(context, crypto); 1908 if (ret) { 1909 const char *msg = krb5_get_error_message(context, ret); 1910 free_PA_S4U2Self(&self); 1911 kdc_log(context, config, 0, 1912 "krb5_verify_checksum failed for S4U2Self: %s", msg); 1913 krb5_free_error_message(context, msg); 1914 goto out; 1915 } 1916 1917 ret = _krb5_principalname2krb5_principal(context, 1918 &tp, 1919 self.name, 1920 self.realm); 1921 free_PA_S4U2Self(&self); 1922 if (ret) 1923 goto out; 1924 1925 ret = krb5_unparse_name(context, tp, &tpn); 1926 if (ret) 1927 goto out; 1928 1929 /* If we were about to put a PAC into the ticket, we better fix it to be the right PAC */ 1930 if(rspac.data) { 1931 krb5_pac p = NULL; 1932 krb5_data_free(&rspac); 1933 ret = _kdc_db_fetch(context, config, tp, HDB_F_GET_CLIENT | flags, 1934 NULL, &s4u2self_impersonated_clientdb, &s4u2self_impersonated_client); 1935 if (ret) { 1936 const char *msg; 1937 1938 /* 1939 * If the client belongs to the same realm as our krbtgt, it 1940 * should exist in the local database. 1941 * 1942 */ 1943 1944 if (ret == HDB_ERR_NOENTRY) 1945 ret = KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN; 1946 msg = krb5_get_error_message(context, ret); 1947 kdc_log(context, config, 1, 1948 "S2U4Self principal to impersonate %s not found in database: %s", 1949 tpn, msg); 1950 krb5_free_error_message(context, msg); 1951 goto out; 1952 } 1953 ret = _kdc_pac_generate(context, s4u2self_impersonated_client, &p); 1954 if (ret) { 1955 kdc_log(context, config, 0, "PAC generation failed for -- %s", 1956 tpn); 1957 goto out; 1958 } 1959 if (p != NULL) { 1960 ret = _krb5_pac_sign(context, p, ticket->ticket.authtime, 1961 s4u2self_impersonated_client->entry.principal, 1962 ekey, &tkey_sign->key, 1963 &rspac); 1964 krb5_pac_free(context, p); 1965 if (ret) { 1966 kdc_log(context, config, 0, "PAC signing failed for -- %s", 1967 tpn); 1968 goto out; 1969 } 1970 } 1971 } 1972 1973 /* 1974 * Check that service doing the impersonating is 1975 * requesting a ticket to it-self. 1976 */ 1977 ret = check_s4u2self(context, config, clientdb, client, sp); 1978 if (ret) { 1979 kdc_log(context, config, 0, "S4U2Self: %s is not allowed " 1980 "to impersonate to service " 1981 "(tried for user %s to service %s)", 1982 cpn, tpn, spn); 1983 goto out; 1984 } 1985 1986 /* 1987 * If the service isn't trusted for authentication to 1988 * delegation, remove the forward flag. 1989 */ 1990 1991 if (client->entry.flags.trusted_for_delegation) { 1992 str = "[forwardable]"; 1993 } else { 1994 b->kdc_options.forwardable = 0; 1995 str = ""; 1996 } 1997 kdc_log(context, config, 0, "s4u2self %s impersonating %s to " 1998 "service %s %s", cpn, tpn, spn, str); 1999 } 2000 } 2001 2002 /* 2003 * Constrained delegation 2004 */ 2005 2006 if (client != NULL 2007 && b->additional_tickets != NULL 2008 && b->additional_tickets->len != 0 2009 && b->kdc_options.enc_tkt_in_skey == 0) 2010 { 2011 int ad_signedpath = 0; 2012 Key *clientkey; 2013 Ticket *t; 2014 2015 /* 2016 * Require that the KDC have issued the service's krbtgt (not 2017 * self-issued ticket with kimpersonate(1). 2018 */ 2019 if (!signedpath) { 2020 ret = KRB5KDC_ERR_BADOPTION; 2021 kdc_log(context, config, 0, 2022 "Constrained delegation done on service ticket %s/%s", 2023 cpn, spn); 2024 goto out; 2025 } 2026 2027 t = &b->additional_tickets->val[0]; 2028 2029 ret = hdb_enctype2key(context, &client->entry, 2030 t->enc_part.etype, &clientkey); 2031 if(ret){ 2032 ret = KRB5KDC_ERR_ETYPE_NOSUPP; /* XXX */ 2033 goto out; 2034 } 2035 2036 ret = krb5_decrypt_ticket(context, t, &clientkey->key, &adtkt, 0); 2037 if (ret) { 2038 kdc_log(context, config, 0, 2039 "failed to decrypt ticket for " 2040 "constrained delegation from %s to %s ", cpn, spn); 2041 goto out; 2042 } 2043 2044 ret = _krb5_principalname2krb5_principal(context, 2045 &tp, 2046 adtkt.cname, 2047 adtkt.crealm); 2048 if (ret) 2049 goto out; 2050 2051 ret = krb5_unparse_name(context, tp, &tpn); 2052 if (ret) 2053 goto out; 2054 2055 ret = _krb5_principalname2krb5_principal(context, 2056 &dp, 2057 t->sname, 2058 t->realm); 2059 if (ret) 2060 goto out; 2061 2062 ret = krb5_unparse_name(context, dp, &dpn); 2063 if (ret) 2064 goto out; 2065 2066 /* check that ticket is valid */ 2067 if (adtkt.flags.forwardable == 0) { 2068 kdc_log(context, config, 0, 2069 "Missing forwardable flag on ticket for " 2070 "constrained delegation from %s (%s) as %s to %s ", 2071 cpn, dpn, tpn, spn); 2072 ret = KRB5KDC_ERR_BADOPTION; 2073 goto out; 2074 } 2075 2076 ret = check_constrained_delegation(context, config, clientdb, 2077 client, server, sp); 2078 if (ret) { 2079 kdc_log(context, config, 0, 2080 "constrained delegation from %s (%s) as %s to %s not allowed", 2081 cpn, dpn, tpn, spn); 2082 goto out; 2083 } 2084 2085 ret = verify_flags(context, config, &adtkt, tpn); 2086 if (ret) { 2087 goto out; 2088 } 2089 2090 krb5_data_free(&rspac); 2091 2092 /* 2093 * generate the PAC for the user. 2094 * 2095 * TODO: pass in t->sname and t->realm and build 2096 * a S4U_DELEGATION_INFO blob to the PAC. 2097 */ 2098 ret = check_PAC(context, config, tp, dp, 2099 client, server, krbtgt, 2100 &clientkey->key, &tkey_check->key, 2101 ekey, &tkey_sign->key, 2102 &adtkt, &rspac, &ad_signedpath); 2103 if (ret) { 2104 const char *msg = krb5_get_error_message(context, ret); 2105 kdc_log(context, config, 0, 2106 "Verify delegated PAC failed to %s for client" 2107 "%s (%s) as %s from %s with %s", 2108 spn, cpn, dpn, tpn, from, msg); 2109 krb5_free_error_message(context, msg); 2110 goto out; 2111 } 2112 2113 /* 2114 * Check that the KDC issued the user's ticket. 2115 */ 2116 ret = check_KRB5SignedPath(context, 2117 config, 2118 krbtgt, 2119 cp, 2120 &adtkt, 2121 NULL, 2122 &ad_signedpath); 2123 if (ret) { 2124 const char *msg = krb5_get_error_message(context, ret); 2125 kdc_log(context, config, 0, 2126 "KRB5SignedPath check from service %s failed " 2127 "for delegation to %s for client %s (%s)" 2128 "from %s failed with %s", 2129 spn, tpn, dpn, cpn, from, msg); 2130 krb5_free_error_message(context, msg); 2131 goto out; 2132 } 2133 2134 if (!ad_signedpath) { 2135 ret = KRB5KDC_ERR_BADOPTION; 2136 kdc_log(context, config, 0, 2137 "Ticket not signed with PAC nor SignedPath service %s failed " 2138 "for delegation to %s for client %s (%s)" 2139 "from %s", 2140 spn, tpn, dpn, cpn, from); 2141 goto out; 2142 } 2143 2144 kdc_log(context, config, 0, "constrained delegation for %s " 2145 "from %s (%s) to %s", tpn, cpn, dpn, spn); 2146 } 2147 2148 /* 2149 * Check flags 2150 */ 2151 2152 ret = kdc_check_flags(context, config, 2153 client, cpn, 2154 server, spn, 2155 FALSE); 2156 if(ret) 2157 goto out; 2158 2159 if((b->kdc_options.validate || b->kdc_options.renew) && 2160 !krb5_principal_compare(context, 2161 krbtgt->entry.principal, 2162 server->entry.principal)){ 2163 kdc_log(context, config, 0, "Inconsistent request."); 2164 ret = KRB5KDC_ERR_SERVER_NOMATCH; 2165 goto out; 2166 } 2167 2168 /* check for valid set of addresses */ 2169 if(!_kdc_check_addresses(context, config, tgt->caddr, from_addr)) { 2170 ret = KRB5KRB_AP_ERR_BADADDR; 2171 kdc_log(context, config, 0, "Request from wrong address"); 2172 goto out; 2173 } 2174 2175 /* 2176 * If this is an referral, add server referral data to the 2177 * auth_data reply . 2178 */ 2179 if (ref_realm) { 2180 PA_DATA pa; 2181 krb5_crypto crypto; 2182 2183 kdc_log(context, config, 0, 2184 "Adding server referral to %s", ref_realm); 2185 2186 ret = krb5_crypto_init(context, &sessionkey, 0, &crypto); 2187 if (ret) 2188 goto out; 2189 2190 ret = build_server_referral(context, config, crypto, ref_realm, 2191 NULL, s, &pa.padata_value); 2192 krb5_crypto_destroy(context, crypto); 2193 if (ret) { 2194 kdc_log(context, config, 0, 2195 "Failed building server referral"); 2196 goto out; 2197 } 2198 pa.padata_type = KRB5_PADATA_SERVER_REFERRAL; 2199 2200 ret = add_METHOD_DATA(&enc_pa_data, &pa); 2201 krb5_data_free(&pa.padata_value); 2202 if (ret) { 2203 kdc_log(context, config, 0, 2204 "Add server referral METHOD-DATA failed"); 2205 goto out; 2206 } 2207 } 2208 2209 /* 2210 * 2211 */ 2212 2213 ret = tgs_make_reply(context, 2214 config, 2215 b, 2216 tp, 2217 tgt, 2218 replykey, 2219 rk_is_subkey, 2220 ekey, 2221 &sessionkey, 2222 kvno, 2223 *auth_data, 2224 server, 2225 rsp, 2226 spn, 2227 client, 2228 cp, 2229 krbtgt_out, 2230 krbtgt_etype, 2231 spp, 2232 &rspac, 2233 &enc_pa_data, 2234 e_text, 2235 reply); 2236 2237 out: 2238 if (tpn != cpn) 2239 free(tpn); 2240 free(spn); 2241 free(cpn); 2242 if (dpn) 2243 free(dpn); 2244 2245 krb5_data_free(&rspac); 2246 krb5_free_keyblock_contents(context, &sessionkey); 2247 if(krbtgt_out) 2248 _kdc_free_ent(context, krbtgt_out); 2249 if(server) 2250 _kdc_free_ent(context, server); 2251 if(client) 2252 _kdc_free_ent(context, client); 2253 if(s4u2self_impersonated_client) 2254 _kdc_free_ent(context, s4u2self_impersonated_client); 2255 2256 if (tp && tp != cp) 2257 krb5_free_principal(context, tp); 2258 if (cp) 2259 krb5_free_principal(context, cp); 2260 if (dp) 2261 krb5_free_principal(context, dp); 2262 if (sp) 2263 krb5_free_principal(context, sp); 2264 if (ref_realm) 2265 free(ref_realm); 2266 free_METHOD_DATA(&enc_pa_data); 2267 2268 free_EncTicketPart(&adtkt); 2269 2270 return ret; 2271 } 2272 2273 /* 2274 * 2275 */ 2276 2277 krb5_error_code 2278 _kdc_tgs_rep(krb5_context context, 2279 krb5_kdc_configuration *config, 2280 KDC_REQ *req, 2281 krb5_data *data, 2282 const char *from, 2283 struct sockaddr *from_addr, 2284 int datagram_reply) 2285 { 2286 AuthorizationData *auth_data = NULL; 2287 krb5_error_code ret; 2288 int i = 0; 2289 const PA_DATA *tgs_req; 2290 2291 hdb_entry_ex *krbtgt = NULL; 2292 krb5_ticket *ticket = NULL; 2293 const char *e_text = NULL; 2294 krb5_enctype krbtgt_etype = ETYPE_NULL; 2295 2296 krb5_keyblock *replykey = NULL; 2297 int rk_is_subkey = 0; 2298 time_t *csec = NULL; 2299 int *cusec = NULL; 2300 2301 if(req->padata == NULL){ 2302 ret = KRB5KDC_ERR_PREAUTH_REQUIRED; /* XXX ??? */ 2303 kdc_log(context, config, 0, 2304 "TGS-REQ from %s without PA-DATA", from); 2305 goto out; 2306 } 2307 2308 tgs_req = _kdc_find_padata(req, &i, KRB5_PADATA_TGS_REQ); 2309 2310 if(tgs_req == NULL){ 2311 ret = KRB5KDC_ERR_PADATA_TYPE_NOSUPP; 2312 2313 kdc_log(context, config, 0, 2314 "TGS-REQ from %s without PA-TGS-REQ", from); 2315 goto out; 2316 } 2317 ret = tgs_parse_request(context, config, 2318 &req->req_body, tgs_req, 2319 &krbtgt, 2320 &krbtgt_etype, 2321 &ticket, 2322 &e_text, 2323 from, from_addr, 2324 &csec, &cusec, 2325 &auth_data, 2326 &replykey, 2327 &rk_is_subkey); 2328 if (ret == HDB_ERR_NOT_FOUND_HERE) { 2329 /* kdc_log() is called in tgs_parse_request() */ 2330 goto out; 2331 } 2332 if (ret) { 2333 kdc_log(context, config, 0, 2334 "Failed parsing TGS-REQ from %s", from); 2335 goto out; 2336 } 2337 2338 ret = tgs_build_reply(context, 2339 config, 2340 req, 2341 &req->req_body, 2342 krbtgt, 2343 krbtgt_etype, 2344 replykey, 2345 rk_is_subkey, 2346 ticket, 2347 data, 2348 from, 2349 &e_text, 2350 &auth_data, 2351 from_addr); 2352 if (ret) { 2353 kdc_log(context, config, 0, 2354 "Failed building TGS-REP to %s", from); 2355 goto out; 2356 } 2357 2358 /* */ 2359 if (datagram_reply && data->length > config->max_datagram_reply_length) { 2360 krb5_data_free(data); 2361 ret = KRB5KRB_ERR_RESPONSE_TOO_BIG; 2362 e_text = "Reply packet too large"; 2363 } 2364 2365 out: 2366 if (replykey) 2367 krb5_free_keyblock(context, replykey); 2368 if(ret && ret != HDB_ERR_NOT_FOUND_HERE && data->data == NULL){ 2369 krb5_mk_error(context, 2370 ret, 2371 NULL, 2372 NULL, 2373 NULL, 2374 NULL, 2375 csec, 2376 cusec, 2377 data); 2378 ret = 0; 2379 } 2380 free(csec); 2381 free(cusec); 2382 if (ticket) 2383 krb5_free_ticket(context, ticket); 2384 if(krbtgt) 2385 _kdc_free_ent(context, krbtgt); 2386 2387 if (auth_data) { 2388 free_AuthorizationData(auth_data); 2389 free(auth_data); 2390 } 2391 2392 return ret; 2393 } 2394