1 /* $NetBSD: cfx.c,v 1.3 2023/06/19 21:41:43 christos Exp $ */ 2 3 /* 4 * Copyright (c) 2003, PADL Software Pty Ltd. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * 3. Neither the name of PADL Software nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY PADL SOFTWARE AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL PADL SOFTWARE OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #include "gsskrb5_locl.h" 36 37 /* 38 * Implementation of RFC 4121 39 */ 40 41 #define CFXSentByAcceptor (1 << 0) 42 #define CFXSealed (1 << 1) 43 #define CFXAcceptorSubkey (1 << 2) 44 45 krb5_error_code 46 _gsskrb5cfx_wrap_length_cfx(krb5_context context, 47 krb5_crypto crypto, 48 int conf_req_flag, 49 int dce_style, 50 size_t input_length, 51 size_t *output_length, 52 size_t *cksumsize, 53 uint16_t *padlength) 54 { 55 krb5_error_code ret; 56 krb5_cksumtype type; 57 58 /* 16-byte header is always first */ 59 *output_length = sizeof(gss_cfx_wrap_token_desc); 60 *padlength = 0; 61 62 ret = krb5_crypto_get_checksum_type(context, crypto, &type); 63 if (ret) 64 return ret; 65 66 ret = krb5_checksumsize(context, type, cksumsize); 67 if (ret) 68 return ret; 69 70 if (conf_req_flag) { 71 size_t padsize; 72 73 /* Header is concatenated with data before encryption */ 74 input_length += sizeof(gss_cfx_wrap_token_desc); 75 76 if (dce_style) { 77 ret = krb5_crypto_getblocksize(context, crypto, &padsize); 78 } else { 79 ret = krb5_crypto_getpadsize(context, crypto, &padsize); 80 } 81 if (ret) { 82 return ret; 83 } 84 if (padsize > 1) { 85 /* XXX check this */ 86 *padlength = padsize - (input_length % padsize); 87 88 /* We add the pad ourselves (noted here for completeness only) */ 89 input_length += *padlength; 90 } 91 92 *output_length += krb5_get_wrapped_length(context, 93 crypto, input_length); 94 } else { 95 /* Checksum is concatenated with data */ 96 *output_length += input_length + *cksumsize; 97 } 98 99 assert(*output_length > input_length); 100 101 return 0; 102 } 103 104 OM_uint32 105 _gssapi_wrap_size_cfx(OM_uint32 *minor_status, 106 const gsskrb5_ctx ctx, 107 krb5_context context, 108 int conf_req_flag, 109 gss_qop_t qop_req, 110 OM_uint32 req_output_size, 111 OM_uint32 *max_input_size) 112 { 113 krb5_error_code ret; 114 115 *max_input_size = 0; 116 117 /* 16-byte header is always first */ 118 if (req_output_size < 16) 119 return 0; 120 req_output_size -= 16; 121 122 if (conf_req_flag) { 123 size_t wrapped_size, sz; 124 125 wrapped_size = req_output_size + 1; 126 do { 127 wrapped_size--; 128 sz = krb5_get_wrapped_length(context, 129 ctx->crypto, wrapped_size); 130 } while (wrapped_size && sz > req_output_size); 131 if (wrapped_size == 0) 132 return 0; 133 134 /* inner header */ 135 if (wrapped_size < 16) 136 return 0; 137 138 wrapped_size -= 16; 139 140 *max_input_size = wrapped_size; 141 } else { 142 krb5_cksumtype type; 143 size_t cksumsize; 144 145 ret = krb5_crypto_get_checksum_type(context, ctx->crypto, &type); 146 if (ret) 147 return ret; 148 149 ret = krb5_checksumsize(context, type, &cksumsize); 150 if (ret) 151 return ret; 152 153 if (req_output_size < cksumsize) 154 return 0; 155 156 /* Checksum is concatenated with data */ 157 *max_input_size = req_output_size - cksumsize; 158 } 159 160 return 0; 161 } 162 163 /* 164 * Rotate "rrc" bytes to the front or back 165 */ 166 167 static krb5_error_code 168 rrc_rotate(void *data, size_t len, uint16_t rrc, krb5_boolean unrotate) 169 { 170 u_char *tmp, buf[256]; 171 size_t left; 172 173 if (len == 0) 174 return 0; 175 176 rrc %= len; 177 178 if (rrc == 0) 179 return 0; 180 181 left = len - rrc; 182 183 if (rrc <= sizeof(buf)) { 184 tmp = buf; 185 } else { 186 tmp = malloc(rrc); 187 if (tmp == NULL) 188 return ENOMEM; 189 } 190 191 if (unrotate) { 192 memcpy(tmp, data, rrc); 193 memmove(data, (u_char *)data + rrc, left); 194 memcpy((u_char *)data + left, tmp, rrc); 195 } else { 196 memcpy(tmp, (u_char *)data + left, rrc); 197 memmove((u_char *)data + rrc, data, left); 198 memcpy(data, tmp, rrc); 199 } 200 201 if (rrc > sizeof(buf)) 202 free(tmp); 203 204 return 0; 205 } 206 207 gss_iov_buffer_desc * 208 _gk_find_buffer(gss_iov_buffer_desc *iov, int iov_count, OM_uint32 type) 209 { 210 int i; 211 gss_iov_buffer_t iovp = GSS_C_NO_IOV_BUFFER; 212 213 if (iov == GSS_C_NO_IOV_BUFFER) 214 return GSS_C_NO_IOV_BUFFER; 215 216 /* 217 * This function is used to find header, padding or trailer buffers 218 * which are singletons; return NULL if multiple instances are found. 219 */ 220 for (i = 0; i < iov_count; i++) { 221 if (type == GSS_IOV_BUFFER_TYPE(iov[i].type)) { 222 if (iovp == GSS_C_NO_IOV_BUFFER) 223 iovp = &iov[i]; 224 else 225 return GSS_C_NO_IOV_BUFFER; 226 } 227 } 228 229 /* 230 * For compatibility with SSPI, an empty padding buffer is treated 231 * equivalent to an absent padding buffer (unless the caller is 232 * requesting that a padding buffer be allocated). 233 */ 234 if (iovp && 235 iovp->buffer.length == 0 && 236 type == GSS_IOV_BUFFER_TYPE_PADDING && 237 (GSS_IOV_BUFFER_FLAGS(iovp->type) & GSS_IOV_BUFFER_FLAG_ALLOCATE) == 0) 238 iovp = NULL; 239 240 return iovp; 241 } 242 243 OM_uint32 244 _gk_allocate_buffer(OM_uint32 *minor_status, gss_iov_buffer_desc *buffer, size_t size) 245 { 246 if (buffer->type & GSS_IOV_BUFFER_FLAG_ALLOCATED) { 247 if (buffer->buffer.length == size) 248 return GSS_S_COMPLETE; 249 free(buffer->buffer.value); 250 } 251 252 buffer->buffer.value = malloc(size); 253 buffer->buffer.length = size; 254 if (buffer->buffer.value == NULL) { 255 *minor_status = ENOMEM; 256 return GSS_S_FAILURE; 257 } 258 buffer->type |= GSS_IOV_BUFFER_FLAG_ALLOCATED; 259 260 return GSS_S_COMPLETE; 261 } 262 263 264 OM_uint32 265 _gk_verify_buffers(OM_uint32 *minor_status, 266 const gsskrb5_ctx ctx, 267 const gss_iov_buffer_desc *header, 268 const gss_iov_buffer_desc *padding, 269 const gss_iov_buffer_desc *trailer, 270 int block_cipher) 271 { 272 if (header == NULL) { 273 *minor_status = EINVAL; 274 return GSS_S_FAILURE; 275 } 276 277 if (IS_DCE_STYLE(ctx)) { 278 /* 279 * In DCE style mode we reject having a padding or trailer buffer 280 */ 281 if (padding) { 282 *minor_status = EINVAL; 283 return GSS_S_FAILURE; 284 } 285 if (trailer) { 286 *minor_status = EINVAL; 287 return GSS_S_FAILURE; 288 } 289 } else { 290 /* 291 * In non-DCE style mode we require having a padding buffer for 292 * encryption types that do not behave as stream ciphers. This 293 * check is superfluous for now, as only RC4 and RFC4121 enctypes 294 * are presently implemented for the IOV APIs; be defensive. 295 */ 296 if (block_cipher && padding == NULL) { 297 *minor_status = EINVAL; 298 return GSS_S_FAILURE; 299 } 300 } 301 302 *minor_status = 0; 303 return GSS_S_COMPLETE; 304 } 305 306 OM_uint32 307 _gssapi_wrap_cfx_iov(OM_uint32 *minor_status, 308 gsskrb5_ctx ctx, 309 krb5_context context, 310 int conf_req_flag, 311 int *conf_state, 312 gss_iov_buffer_desc *iov, 313 int iov_count) 314 { 315 OM_uint32 major_status, junk; 316 gss_iov_buffer_desc *header, *trailer, *padding; 317 size_t gsshsize, k5hsize; 318 size_t gsstsize, k5tsize; 319 size_t rrc = 0, ec = 0; 320 int i; 321 gss_cfx_wrap_token token; 322 krb5_error_code ret; 323 int32_t seq_number; 324 unsigned usage; 325 krb5_crypto_iov *data = NULL; 326 327 header = _gk_find_buffer(iov, iov_count, GSS_IOV_BUFFER_TYPE_HEADER); 328 if (header == NULL) { 329 *minor_status = EINVAL; 330 return GSS_S_FAILURE; 331 } 332 333 padding = _gk_find_buffer(iov, iov_count, GSS_IOV_BUFFER_TYPE_PADDING); 334 if (padding != NULL) { 335 padding->buffer.length = 0; 336 } 337 338 trailer = _gk_find_buffer(iov, iov_count, GSS_IOV_BUFFER_TYPE_TRAILER); 339 340 major_status = _gk_verify_buffers(minor_status, ctx, header, 341 padding, trailer, FALSE); 342 if (major_status != GSS_S_COMPLETE) { 343 return major_status; 344 } 345 346 if (conf_req_flag) { 347 size_t k5psize = 0; 348 size_t k5pbase = 0; 349 size_t k5bsize = 0; 350 size_t size = 0; 351 352 for (i = 0; i < iov_count; i++) { 353 switch (GSS_IOV_BUFFER_TYPE(iov[i].type)) { 354 case GSS_IOV_BUFFER_TYPE_DATA: 355 size += iov[i].buffer.length; 356 break; 357 default: 358 break; 359 } 360 } 361 362 size += sizeof(gss_cfx_wrap_token_desc); 363 364 *minor_status = krb5_crypto_length(context, ctx->crypto, 365 KRB5_CRYPTO_TYPE_HEADER, 366 &k5hsize); 367 if (*minor_status) 368 return GSS_S_FAILURE; 369 370 *minor_status = krb5_crypto_length(context, ctx->crypto, 371 KRB5_CRYPTO_TYPE_TRAILER, 372 &k5tsize); 373 if (*minor_status) 374 return GSS_S_FAILURE; 375 376 *minor_status = krb5_crypto_length(context, ctx->crypto, 377 KRB5_CRYPTO_TYPE_PADDING, 378 &k5pbase); 379 if (*minor_status) 380 return GSS_S_FAILURE; 381 382 if (k5pbase > 1) { 383 k5psize = k5pbase - (size % k5pbase); 384 } else { 385 k5psize = 0; 386 } 387 388 if (k5psize == 0 && IS_DCE_STYLE(ctx)) { 389 *minor_status = krb5_crypto_getblocksize(context, ctx->crypto, 390 &k5bsize); 391 if (*minor_status) 392 return GSS_S_FAILURE; 393 ec = k5bsize; 394 } else { 395 ec = k5psize; 396 } 397 398 gsshsize = sizeof(gss_cfx_wrap_token_desc) + k5hsize; 399 gsstsize = sizeof(gss_cfx_wrap_token_desc) + ec + k5tsize; 400 } else { 401 if (IS_DCE_STYLE(ctx)) { 402 *minor_status = EINVAL; 403 return GSS_S_FAILURE; 404 } 405 406 k5hsize = 0; 407 *minor_status = krb5_crypto_length(context, ctx->crypto, 408 KRB5_CRYPTO_TYPE_CHECKSUM, 409 &k5tsize); 410 if (*minor_status) 411 return GSS_S_FAILURE; 412 413 gsshsize = sizeof(gss_cfx_wrap_token_desc); 414 gsstsize = k5tsize; 415 } 416 417 /* 418 * 419 */ 420 421 if (trailer == NULL) { 422 rrc = gsstsize; 423 if (IS_DCE_STYLE(ctx)) 424 rrc -= ec; 425 gsshsize += gsstsize; 426 } else if (GSS_IOV_BUFFER_FLAGS(trailer->type) & GSS_IOV_BUFFER_FLAG_ALLOCATE) { 427 major_status = _gk_allocate_buffer(minor_status, trailer, gsstsize); 428 if (major_status) 429 goto failure; 430 } else if (trailer->buffer.length < gsstsize) { 431 *minor_status = KRB5_BAD_MSIZE; 432 major_status = GSS_S_FAILURE; 433 goto failure; 434 } else 435 trailer->buffer.length = gsstsize; 436 437 /* 438 * 439 */ 440 441 if (GSS_IOV_BUFFER_FLAGS(header->type) & GSS_IOV_BUFFER_FLAG_ALLOCATE) { 442 major_status = _gk_allocate_buffer(minor_status, header, gsshsize); 443 if (major_status != GSS_S_COMPLETE) 444 goto failure; 445 } else if (header->buffer.length < gsshsize) { 446 *minor_status = KRB5_BAD_MSIZE; 447 major_status = GSS_S_FAILURE; 448 goto failure; 449 } else 450 header->buffer.length = gsshsize; 451 452 token = (gss_cfx_wrap_token)header->buffer.value; 453 454 token->TOK_ID[0] = 0x05; 455 token->TOK_ID[1] = 0x04; 456 token->Flags = 0; 457 token->Filler = 0xFF; 458 459 if ((ctx->more_flags & LOCAL) == 0) 460 token->Flags |= CFXSentByAcceptor; 461 462 if (ctx->more_flags & ACCEPTOR_SUBKEY) 463 token->Flags |= CFXAcceptorSubkey; 464 465 if (ctx->more_flags & LOCAL) 466 usage = KRB5_KU_USAGE_INITIATOR_SEAL; 467 else 468 usage = KRB5_KU_USAGE_ACCEPTOR_SEAL; 469 470 if (conf_req_flag) { 471 /* 472 * In Wrap tokens with confidentiality, the EC field is 473 * used to encode the size (in bytes) of the random filler. 474 */ 475 token->Flags |= CFXSealed; 476 token->EC[0] = (ec >> 8) & 0xFF; 477 token->EC[1] = (ec >> 0) & 0xFF; 478 479 } else { 480 /* 481 * In Wrap tokens without confidentiality, the EC field is 482 * used to encode the size (in bytes) of the trailing 483 * checksum. 484 * 485 * This is not used in the checksum calcuation itself, 486 * because the checksum length could potentially vary 487 * depending on the data length. 488 */ 489 token->EC[0] = 0; 490 token->EC[1] = 0; 491 } 492 493 /* 494 * In Wrap tokens that provide for confidentiality, the RRC 495 * field in the header contains the hex value 00 00 before 496 * encryption. 497 * 498 * In Wrap tokens that do not provide for confidentiality, 499 * both the EC and RRC fields in the appended checksum 500 * contain the hex value 00 00 for the purpose of calculating 501 * the checksum. 502 */ 503 token->RRC[0] = 0; 504 token->RRC[1] = 0; 505 506 HEIMDAL_MUTEX_lock(&ctx->ctx_id_mutex); 507 krb5_auth_con_getlocalseqnumber(context, 508 ctx->auth_context, 509 &seq_number); 510 _gsskrb5_encode_be_om_uint32(0, &token->SND_SEQ[0]); 511 _gsskrb5_encode_be_om_uint32(seq_number, &token->SND_SEQ[4]); 512 krb5_auth_con_setlocalseqnumber(context, 513 ctx->auth_context, 514 ++seq_number); 515 HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex); 516 517 data = calloc(iov_count + 3, sizeof(data[0])); 518 if (data == NULL) { 519 *minor_status = ENOMEM; 520 major_status = GSS_S_FAILURE; 521 goto failure; 522 } 523 524 if (conf_req_flag) { 525 /* 526 plain packet: 527 528 {"header" | encrypt(plaintext-data | ec-padding | E"header")} 529 530 Expanded, this is with with RRC = 0: 531 532 {"header" | krb5-header | plaintext-data | ec-padding | E"header" | krb5-trailer } 533 534 In DCE-RPC mode == no trailer: RRC = gss "trailer" == length(ec-padding | E"header" | krb5-trailer) 535 536 {"header" | ec-padding | E"header" | krb5-trailer | krb5-header | plaintext-data } 537 */ 538 539 i = 0; 540 data[i].flags = KRB5_CRYPTO_TYPE_HEADER; 541 data[i].data.data = ((uint8_t *)header->buffer.value) + header->buffer.length - k5hsize; 542 data[i].data.length = k5hsize; 543 544 for (i = 1; i < iov_count + 1; i++) { 545 switch (GSS_IOV_BUFFER_TYPE(iov[i - 1].type)) { 546 case GSS_IOV_BUFFER_TYPE_DATA: 547 data[i].flags = KRB5_CRYPTO_TYPE_DATA; 548 break; 549 case GSS_IOV_BUFFER_TYPE_SIGN_ONLY: 550 data[i].flags = KRB5_CRYPTO_TYPE_SIGN_ONLY; 551 break; 552 default: 553 data[i].flags = KRB5_CRYPTO_TYPE_EMPTY; 554 break; 555 } 556 data[i].data.length = iov[i - 1].buffer.length; 557 data[i].data.data = iov[i - 1].buffer.value; 558 } 559 560 /* 561 * Any necessary padding is added here to ensure that the 562 * encrypted token header is always at the end of the 563 * ciphertext. 564 */ 565 566 /* encrypted CFX header in trailer (or after the header if in 567 DCE mode). Copy in header into E"header" 568 */ 569 data[i].flags = KRB5_CRYPTO_TYPE_DATA; 570 if (trailer) 571 data[i].data.data = trailer->buffer.value; 572 else 573 data[i].data.data = ((uint8_t *)header->buffer.value) + sizeof(*token); 574 575 data[i].data.length = ec + sizeof(*token); 576 memset(data[i].data.data, 0xFF, ec); 577 memcpy(((uint8_t *)data[i].data.data) + ec, token, sizeof(*token)); 578 i++; 579 580 /* Kerberos trailer comes after the gss trailer */ 581 data[i].flags = KRB5_CRYPTO_TYPE_TRAILER; 582 data[i].data.data = ((uint8_t *)data[i-1].data.data) + ec + sizeof(*token); 583 data[i].data.length = k5tsize; 584 i++; 585 586 ret = krb5_encrypt_iov_ivec(context, ctx->crypto, usage, data, i, NULL); 587 if (ret != 0) { 588 *minor_status = ret; 589 major_status = GSS_S_FAILURE; 590 goto failure; 591 } 592 593 if (rrc) { 594 token->RRC[0] = (rrc >> 8) & 0xFF; 595 token->RRC[1] = (rrc >> 0) & 0xFF; 596 } 597 598 } else { 599 /* 600 plain packet: 601 602 {data | "header" | gss-trailer (krb5 checksum) 603 604 don't do RRC != 0 605 606 */ 607 608 for (i = 0; i < iov_count; i++) { 609 switch (GSS_IOV_BUFFER_TYPE(iov[i].type)) { 610 case GSS_IOV_BUFFER_TYPE_DATA: 611 data[i].flags = KRB5_CRYPTO_TYPE_DATA; 612 break; 613 case GSS_IOV_BUFFER_TYPE_SIGN_ONLY: 614 data[i].flags = KRB5_CRYPTO_TYPE_SIGN_ONLY; 615 break; 616 default: 617 data[i].flags = KRB5_CRYPTO_TYPE_EMPTY; 618 break; 619 } 620 data[i].data.length = iov[i].buffer.length; 621 data[i].data.data = iov[i].buffer.value; 622 } 623 624 data[i].flags = KRB5_CRYPTO_TYPE_DATA; 625 data[i].data.data = header->buffer.value; 626 data[i].data.length = sizeof(gss_cfx_wrap_token_desc); 627 i++; 628 629 data[i].flags = KRB5_CRYPTO_TYPE_CHECKSUM; 630 if (trailer) { 631 data[i].data.data = trailer->buffer.value; 632 } else { 633 data[i].data.data = (uint8_t *)header->buffer.value + 634 sizeof(gss_cfx_wrap_token_desc); 635 } 636 data[i].data.length = k5tsize; 637 i++; 638 639 ret = krb5_create_checksum_iov(context, ctx->crypto, usage, data, i, NULL); 640 if (ret) { 641 *minor_status = ret; 642 major_status = GSS_S_FAILURE; 643 goto failure; 644 } 645 646 if (rrc) { 647 token->RRC[0] = (rrc >> 8) & 0xFF; 648 token->RRC[1] = (rrc >> 0) & 0xFF; 649 } 650 651 token->EC[0] = (k5tsize >> 8) & 0xFF; 652 token->EC[1] = (k5tsize >> 0) & 0xFF; 653 } 654 655 if (conf_state != NULL) 656 *conf_state = conf_req_flag; 657 658 free(data); 659 660 *minor_status = 0; 661 return GSS_S_COMPLETE; 662 663 failure: 664 if (data) 665 free(data); 666 667 gss_release_iov_buffer(&junk, iov, iov_count); 668 669 return major_status; 670 } 671 672 /* This is slowpath */ 673 static OM_uint32 674 unrotate_iov(OM_uint32 *minor_status, size_t rrc, gss_iov_buffer_desc *iov, int iov_count) 675 { 676 uint8_t *p, *q; 677 size_t len = 0, skip; 678 int i; 679 680 for (i = 0; i < iov_count; i++) 681 if (GSS_IOV_BUFFER_TYPE(iov[i].type) == GSS_IOV_BUFFER_TYPE_DATA || 682 GSS_IOV_BUFFER_TYPE(iov[i].type) == GSS_IOV_BUFFER_TYPE_PADDING || 683 GSS_IOV_BUFFER_TYPE(iov[i].type) == GSS_IOV_BUFFER_TYPE_TRAILER) 684 len += iov[i].buffer.length; 685 686 p = malloc(len); 687 if (p == NULL) { 688 *minor_status = ENOMEM; 689 return GSS_S_FAILURE; 690 } 691 q = p; 692 693 /* copy up */ 694 695 for (i = 0; i < iov_count; i++) { 696 if (GSS_IOV_BUFFER_TYPE(iov[i].type) == GSS_IOV_BUFFER_TYPE_DATA || 697 GSS_IOV_BUFFER_TYPE(iov[i].type) == GSS_IOV_BUFFER_TYPE_PADDING || 698 GSS_IOV_BUFFER_TYPE(iov[i].type) == GSS_IOV_BUFFER_TYPE_TRAILER) 699 { 700 memcpy(q, iov[i].buffer.value, iov[i].buffer.length); 701 q += iov[i].buffer.length; 702 } 703 } 704 assert((size_t)(q - p) == len); 705 706 /* unrotate first part */ 707 q = p + rrc; 708 skip = rrc; 709 for (i = 0; i < iov_count; i++) { 710 if (GSS_IOV_BUFFER_TYPE(iov[i].type) == GSS_IOV_BUFFER_TYPE_DATA || 711 GSS_IOV_BUFFER_TYPE(iov[i].type) == GSS_IOV_BUFFER_TYPE_PADDING || 712 GSS_IOV_BUFFER_TYPE(iov[i].type) == GSS_IOV_BUFFER_TYPE_TRAILER) 713 { 714 if (iov[i].buffer.length <= skip) { 715 skip -= iov[i].buffer.length; 716 } else { 717 /* copy back to original buffer */ 718 memcpy(((uint8_t *)iov[i].buffer.value) + skip, q, iov[i].buffer.length - skip); 719 q += iov[i].buffer.length - skip; 720 skip = 0; 721 } 722 } 723 } 724 /* copy trailer */ 725 q = p; 726 skip = rrc; 727 for (i = 0; i < iov_count; i++) { 728 if (GSS_IOV_BUFFER_TYPE(iov[i].type) == GSS_IOV_BUFFER_TYPE_DATA || 729 GSS_IOV_BUFFER_TYPE(iov[i].type) == GSS_IOV_BUFFER_TYPE_PADDING || 730 GSS_IOV_BUFFER_TYPE(iov[i].type) == GSS_IOV_BUFFER_TYPE_TRAILER) 731 { 732 memcpy(iov[i].buffer.value, q, min(iov[i].buffer.length, skip)); 733 if (iov[i].buffer.length > skip) 734 break; 735 skip -= iov[i].buffer.length; 736 q += iov[i].buffer.length; 737 } 738 } 739 free(p); 740 return GSS_S_COMPLETE; 741 } 742 743 744 OM_uint32 745 _gssapi_unwrap_cfx_iov(OM_uint32 *minor_status, 746 gsskrb5_ctx ctx, 747 krb5_context context, 748 int *conf_state, 749 gss_qop_t *qop_state, 750 gss_iov_buffer_desc *iov, 751 int iov_count) 752 { 753 OM_uint32 seq_number_lo, seq_number_hi, major_status, junk; 754 gss_iov_buffer_desc *header, *trailer, *padding; 755 gss_cfx_wrap_token token, ttoken; 756 u_char token_flags; 757 krb5_error_code ret; 758 unsigned usage; 759 uint16_t ec, rrc; 760 krb5_crypto_iov *data = NULL; 761 int i, j; 762 763 *minor_status = 0; 764 765 header = _gk_find_buffer(iov, iov_count, GSS_IOV_BUFFER_TYPE_HEADER); 766 if (header == NULL) { 767 *minor_status = EINVAL; 768 return GSS_S_FAILURE; 769 } 770 771 if (header->buffer.length < sizeof(*token)) /* we check exact below */ 772 return GSS_S_DEFECTIVE_TOKEN; 773 774 padding = _gk_find_buffer(iov, iov_count, GSS_IOV_BUFFER_TYPE_PADDING); 775 if (padding != NULL && padding->buffer.length != 0) { 776 *minor_status = EINVAL; 777 return GSS_S_FAILURE; 778 } 779 780 trailer = _gk_find_buffer(iov, iov_count, GSS_IOV_BUFFER_TYPE_TRAILER); 781 782 major_status = _gk_verify_buffers(minor_status, ctx, header, 783 padding, trailer, FALSE); 784 if (major_status != GSS_S_COMPLETE) { 785 return major_status; 786 } 787 788 token = (gss_cfx_wrap_token)header->buffer.value; 789 790 if (token->TOK_ID[0] != 0x05 || token->TOK_ID[1] != 0x04) 791 return GSS_S_DEFECTIVE_TOKEN; 792 793 /* Ignore unknown flags */ 794 token_flags = token->Flags & 795 (CFXSentByAcceptor | CFXSealed | CFXAcceptorSubkey); 796 797 if (token_flags & CFXSentByAcceptor) { 798 if ((ctx->more_flags & LOCAL) == 0) 799 return GSS_S_DEFECTIVE_TOKEN; 800 } 801 802 if (ctx->more_flags & ACCEPTOR_SUBKEY) { 803 if ((token_flags & CFXAcceptorSubkey) == 0) 804 return GSS_S_DEFECTIVE_TOKEN; 805 } else { 806 if (token_flags & CFXAcceptorSubkey) 807 return GSS_S_DEFECTIVE_TOKEN; 808 } 809 810 if (token->Filler != 0xFF) 811 return GSS_S_DEFECTIVE_TOKEN; 812 813 if (conf_state != NULL) 814 *conf_state = (token_flags & CFXSealed) ? 1 : 0; 815 816 ec = (token->EC[0] << 8) | token->EC[1]; 817 rrc = (token->RRC[0] << 8) | token->RRC[1]; 818 819 /* 820 * Check sequence number 821 */ 822 _gsskrb5_decode_be_om_uint32(&token->SND_SEQ[0], &seq_number_hi); 823 _gsskrb5_decode_be_om_uint32(&token->SND_SEQ[4], &seq_number_lo); 824 if (seq_number_hi) { 825 /* no support for 64-bit sequence numbers */ 826 *minor_status = ERANGE; 827 return GSS_S_UNSEQ_TOKEN; 828 } 829 830 HEIMDAL_MUTEX_lock(&ctx->ctx_id_mutex); 831 ret = _gssapi_msg_order_check(ctx->order, seq_number_lo); 832 if (ret != 0) { 833 *minor_status = 0; 834 HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex); 835 return ret; 836 } 837 HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex); 838 839 /* 840 * Decrypt and/or verify checksum 841 */ 842 843 if (ctx->more_flags & LOCAL) { 844 usage = KRB5_KU_USAGE_ACCEPTOR_SEAL; 845 } else { 846 usage = KRB5_KU_USAGE_INITIATOR_SEAL; 847 } 848 849 data = calloc(iov_count + 3, sizeof(data[0])); 850 if (data == NULL) { 851 *minor_status = ENOMEM; 852 major_status = GSS_S_FAILURE; 853 goto failure; 854 } 855 856 if (token_flags & CFXSealed) { 857 size_t k5tsize, k5hsize; 858 859 krb5_crypto_length(context, ctx->crypto, KRB5_CRYPTO_TYPE_HEADER, &k5hsize); 860 krb5_crypto_length(context, ctx->crypto, KRB5_CRYPTO_TYPE_TRAILER, &k5tsize); 861 862 /* Rotate by RRC; bogus to do this in-place XXX */ 863 /* Check RRC */ 864 865 if (trailer == NULL) { 866 size_t gsstsize = k5tsize + sizeof(*token); 867 size_t gsshsize = k5hsize + sizeof(*token); 868 869 if (rrc != gsstsize) { 870 major_status = GSS_S_DEFECTIVE_TOKEN; 871 goto failure; 872 } 873 874 if (IS_DCE_STYLE(ctx)) 875 gsstsize += ec; 876 877 gsshsize += gsstsize; 878 879 if (header->buffer.length != gsshsize) { 880 major_status = GSS_S_DEFECTIVE_TOKEN; 881 goto failure; 882 } 883 } else if (trailer->buffer.length != sizeof(*token) + k5tsize) { 884 major_status = GSS_S_DEFECTIVE_TOKEN; 885 goto failure; 886 } else if (header->buffer.length != sizeof(*token) + k5hsize) { 887 major_status = GSS_S_DEFECTIVE_TOKEN; 888 goto failure; 889 } else if (rrc != 0) { 890 /* go though slowpath */ 891 major_status = unrotate_iov(minor_status, rrc, iov, iov_count); 892 if (major_status) 893 goto failure; 894 } 895 896 i = 0; 897 data[i].flags = KRB5_CRYPTO_TYPE_HEADER; 898 data[i].data.data = ((uint8_t *)header->buffer.value) + header->buffer.length - k5hsize; 899 data[i].data.length = k5hsize; 900 i++; 901 902 for (j = 0; j < iov_count; i++, j++) { 903 switch (GSS_IOV_BUFFER_TYPE(iov[j].type)) { 904 case GSS_IOV_BUFFER_TYPE_DATA: 905 data[i].flags = KRB5_CRYPTO_TYPE_DATA; 906 break; 907 case GSS_IOV_BUFFER_TYPE_SIGN_ONLY: 908 data[i].flags = KRB5_CRYPTO_TYPE_SIGN_ONLY; 909 break; 910 default: 911 data[i].flags = KRB5_CRYPTO_TYPE_EMPTY; 912 break; 913 } 914 data[i].data.length = iov[j].buffer.length; 915 data[i].data.data = iov[j].buffer.value; 916 } 917 918 /* encrypted CFX header in trailer (or after the header if in 919 DCE mode). Copy in header into E"header" 920 */ 921 data[i].flags = KRB5_CRYPTO_TYPE_DATA; 922 if (trailer) { 923 data[i].data.data = trailer->buffer.value; 924 } else { 925 data[i].data.data = ((uint8_t *)header->buffer.value) + 926 header->buffer.length - k5hsize - k5tsize - ec- sizeof(*token); 927 } 928 929 data[i].data.length = ec + sizeof(*token); 930 ttoken = (gss_cfx_wrap_token)(((uint8_t *)data[i].data.data) + ec); 931 i++; 932 933 /* Kerberos trailer comes after the gss trailer */ 934 data[i].flags = KRB5_CRYPTO_TYPE_TRAILER; 935 data[i].data.data = ((uint8_t *)data[i-1].data.data) + ec + sizeof(*token); 936 data[i].data.length = k5tsize; 937 i++; 938 939 ret = krb5_decrypt_iov_ivec(context, ctx->crypto, usage, data, i, NULL); 940 if (ret != 0) { 941 *minor_status = ret; 942 major_status = GSS_S_FAILURE; 943 goto failure; 944 } 945 946 ttoken->RRC[0] = token->RRC[0]; 947 ttoken->RRC[1] = token->RRC[1]; 948 949 /* Check the integrity of the header */ 950 if (ct_memcmp(ttoken, token, sizeof(*token)) != 0) { 951 major_status = GSS_S_BAD_MIC; 952 goto failure; 953 } 954 } else { 955 size_t gsstsize = ec; 956 size_t gsshsize = sizeof(*token); 957 958 if (trailer == NULL) { 959 /* Check RRC */ 960 if (rrc != gsstsize) { 961 *minor_status = EINVAL; 962 major_status = GSS_S_FAILURE; 963 goto failure; 964 } 965 966 gsshsize += gsstsize; 967 } else if (trailer->buffer.length != gsstsize) { 968 major_status = GSS_S_DEFECTIVE_TOKEN; 969 goto failure; 970 } else if (rrc != 0) { 971 /* Check RRC */ 972 *minor_status = EINVAL; 973 major_status = GSS_S_FAILURE; 974 goto failure; 975 } 976 977 if (header->buffer.length != gsshsize) { 978 major_status = GSS_S_DEFECTIVE_TOKEN; 979 goto failure; 980 } 981 982 for (i = 0; i < iov_count; i++) { 983 switch (GSS_IOV_BUFFER_TYPE(iov[i].type)) { 984 case GSS_IOV_BUFFER_TYPE_DATA: 985 data[i].flags = KRB5_CRYPTO_TYPE_DATA; 986 break; 987 case GSS_IOV_BUFFER_TYPE_SIGN_ONLY: 988 data[i].flags = KRB5_CRYPTO_TYPE_SIGN_ONLY; 989 break; 990 default: 991 data[i].flags = KRB5_CRYPTO_TYPE_EMPTY; 992 break; 993 } 994 data[i].data.length = iov[i].buffer.length; 995 data[i].data.data = iov[i].buffer.value; 996 } 997 998 data[i].flags = KRB5_CRYPTO_TYPE_DATA; 999 data[i].data.data = header->buffer.value; 1000 data[i].data.length = sizeof(*token); 1001 i++; 1002 1003 data[i].flags = KRB5_CRYPTO_TYPE_CHECKSUM; 1004 if (trailer) { 1005 data[i].data.data = trailer->buffer.value; 1006 } else { 1007 data[i].data.data = (uint8_t *)header->buffer.value + 1008 sizeof(*token); 1009 } 1010 data[i].data.length = ec; 1011 i++; 1012 1013 token = (gss_cfx_wrap_token)header->buffer.value; 1014 token->EC[0] = 0; 1015 token->EC[1] = 0; 1016 token->RRC[0] = 0; 1017 token->RRC[1] = 0; 1018 1019 ret = krb5_verify_checksum_iov(context, ctx->crypto, usage, data, i, NULL); 1020 if (ret) { 1021 *minor_status = ret; 1022 major_status = GSS_S_FAILURE; 1023 goto failure; 1024 } 1025 } 1026 1027 if (qop_state != NULL) { 1028 *qop_state = GSS_C_QOP_DEFAULT; 1029 } 1030 1031 free(data); 1032 1033 *minor_status = 0; 1034 return GSS_S_COMPLETE; 1035 1036 failure: 1037 if (data) 1038 free(data); 1039 1040 gss_release_iov_buffer(&junk, iov, iov_count); 1041 1042 return major_status; 1043 } 1044 1045 OM_uint32 1046 _gssapi_wrap_iov_length_cfx(OM_uint32 *minor_status, 1047 gsskrb5_ctx ctx, 1048 krb5_context context, 1049 int conf_req_flag, 1050 gss_qop_t qop_req, 1051 int *conf_state, 1052 gss_iov_buffer_desc *iov, 1053 int iov_count) 1054 { 1055 OM_uint32 major_status; 1056 size_t size; 1057 int i; 1058 gss_iov_buffer_desc *header = NULL; 1059 gss_iov_buffer_desc *padding = NULL; 1060 gss_iov_buffer_desc *trailer = NULL; 1061 size_t gsshsize = 0; 1062 size_t gsstsize = 0; 1063 size_t k5hsize = 0; 1064 size_t k5tsize = 0; 1065 1066 GSSAPI_KRB5_INIT (&context); 1067 *minor_status = 0; 1068 1069 for (size = 0, i = 0; i < iov_count; i++) { 1070 switch(GSS_IOV_BUFFER_TYPE(iov[i].type)) { 1071 case GSS_IOV_BUFFER_TYPE_EMPTY: 1072 break; 1073 case GSS_IOV_BUFFER_TYPE_DATA: 1074 size += iov[i].buffer.length; 1075 break; 1076 case GSS_IOV_BUFFER_TYPE_HEADER: 1077 if (header != NULL) { 1078 *minor_status = 0; 1079 return GSS_S_FAILURE; 1080 } 1081 header = &iov[i]; 1082 break; 1083 case GSS_IOV_BUFFER_TYPE_TRAILER: 1084 if (trailer != NULL) { 1085 *minor_status = 0; 1086 return GSS_S_FAILURE; 1087 } 1088 trailer = &iov[i]; 1089 break; 1090 case GSS_IOV_BUFFER_TYPE_PADDING: 1091 if (padding != NULL) { 1092 *minor_status = 0; 1093 return GSS_S_FAILURE; 1094 } 1095 padding = &iov[i]; 1096 break; 1097 case GSS_IOV_BUFFER_TYPE_SIGN_ONLY: 1098 break; 1099 default: 1100 *minor_status = EINVAL; 1101 return GSS_S_FAILURE; 1102 } 1103 } 1104 1105 major_status = _gk_verify_buffers(minor_status, ctx, header, 1106 padding, trailer, FALSE); 1107 if (major_status != GSS_S_COMPLETE) { 1108 return major_status; 1109 } 1110 1111 if (conf_req_flag) { 1112 size_t k5psize = 0; 1113 size_t k5pbase = 0; 1114 size_t k5bsize = 0; 1115 size_t ec = 0; 1116 1117 size += sizeof(gss_cfx_wrap_token_desc); 1118 1119 *minor_status = krb5_crypto_length(context, ctx->crypto, 1120 KRB5_CRYPTO_TYPE_HEADER, 1121 &k5hsize); 1122 if (*minor_status) 1123 return GSS_S_FAILURE; 1124 1125 *minor_status = krb5_crypto_length(context, ctx->crypto, 1126 KRB5_CRYPTO_TYPE_TRAILER, 1127 &k5tsize); 1128 if (*minor_status) 1129 return GSS_S_FAILURE; 1130 1131 *minor_status = krb5_crypto_length(context, ctx->crypto, 1132 KRB5_CRYPTO_TYPE_PADDING, 1133 &k5pbase); 1134 if (*minor_status) 1135 return GSS_S_FAILURE; 1136 1137 if (k5pbase > 1) { 1138 k5psize = k5pbase - (size % k5pbase); 1139 } else { 1140 k5psize = 0; 1141 } 1142 1143 if (k5psize == 0 && IS_DCE_STYLE(ctx)) { 1144 *minor_status = krb5_crypto_getblocksize(context, ctx->crypto, 1145 &k5bsize); 1146 if (*minor_status) 1147 return GSS_S_FAILURE; 1148 1149 ec = k5bsize; 1150 } else { 1151 ec = k5psize; 1152 } 1153 1154 gsshsize = sizeof(gss_cfx_wrap_token_desc) + k5hsize; 1155 gsstsize = sizeof(gss_cfx_wrap_token_desc) + ec + k5tsize; 1156 } else { 1157 *minor_status = krb5_crypto_length(context, ctx->crypto, 1158 KRB5_CRYPTO_TYPE_CHECKSUM, 1159 &k5tsize); 1160 if (*minor_status) 1161 return GSS_S_FAILURE; 1162 1163 gsshsize = sizeof(gss_cfx_wrap_token_desc); 1164 gsstsize = k5tsize; 1165 } 1166 1167 if (trailer != NULL) { 1168 trailer->buffer.length = gsstsize; 1169 } else { 1170 gsshsize += gsstsize; 1171 } 1172 1173 header->buffer.length = gsshsize; 1174 1175 if (padding) { 1176 /* padding is done via EC and is contained in the header or trailer */ 1177 padding->buffer.length = 0; 1178 } 1179 1180 if (conf_state) { 1181 *conf_state = conf_req_flag; 1182 } 1183 1184 return GSS_S_COMPLETE; 1185 } 1186 1187 1188 1189 1190 OM_uint32 _gssapi_wrap_cfx(OM_uint32 *minor_status, 1191 const gsskrb5_ctx ctx, 1192 krb5_context context, 1193 int conf_req_flag, 1194 const gss_buffer_t input_message_buffer, 1195 int *conf_state, 1196 gss_buffer_t output_message_buffer) 1197 { 1198 gss_cfx_wrap_token token; 1199 krb5_error_code ret; 1200 unsigned usage; 1201 krb5_data cipher; 1202 size_t wrapped_len, cksumsize; 1203 uint16_t padlength, rrc = 0; 1204 int32_t seq_number; 1205 u_char *p; 1206 1207 ret = _gsskrb5cfx_wrap_length_cfx(context, 1208 ctx->crypto, conf_req_flag, 1209 IS_DCE_STYLE(ctx), 1210 input_message_buffer->length, 1211 &wrapped_len, &cksumsize, &padlength); 1212 if (ret != 0) { 1213 *minor_status = ret; 1214 return GSS_S_FAILURE; 1215 } 1216 1217 /* Always rotate encrypted token (if any) and checksum to header */ 1218 rrc = (conf_req_flag ? sizeof(*token) : 0) + (uint16_t)cksumsize; 1219 1220 output_message_buffer->length = wrapped_len; 1221 output_message_buffer->value = malloc(output_message_buffer->length); 1222 if (output_message_buffer->value == NULL) { 1223 *minor_status = ENOMEM; 1224 return GSS_S_FAILURE; 1225 } 1226 1227 p = output_message_buffer->value; 1228 token = (gss_cfx_wrap_token)p; 1229 token->TOK_ID[0] = 0x05; 1230 token->TOK_ID[1] = 0x04; 1231 token->Flags = 0; 1232 token->Filler = 0xFF; 1233 if ((ctx->more_flags & LOCAL) == 0) 1234 token->Flags |= CFXSentByAcceptor; 1235 if (ctx->more_flags & ACCEPTOR_SUBKEY) 1236 token->Flags |= CFXAcceptorSubkey; 1237 if (conf_req_flag) { 1238 /* 1239 * In Wrap tokens with confidentiality, the EC field is 1240 * used to encode the size (in bytes) of the random filler. 1241 */ 1242 token->Flags |= CFXSealed; 1243 token->EC[0] = (padlength >> 8) & 0xFF; 1244 token->EC[1] = (padlength >> 0) & 0xFF; 1245 } else { 1246 /* 1247 * In Wrap tokens without confidentiality, the EC field is 1248 * used to encode the size (in bytes) of the trailing 1249 * checksum. 1250 * 1251 * This is not used in the checksum calcuation itself, 1252 * because the checksum length could potentially vary 1253 * depending on the data length. 1254 */ 1255 token->EC[0] = 0; 1256 token->EC[1] = 0; 1257 } 1258 1259 /* 1260 * In Wrap tokens that provide for confidentiality, the RRC 1261 * field in the header contains the hex value 00 00 before 1262 * encryption. 1263 * 1264 * In Wrap tokens that do not provide for confidentiality, 1265 * both the EC and RRC fields in the appended checksum 1266 * contain the hex value 00 00 for the purpose of calculating 1267 * the checksum. 1268 */ 1269 token->RRC[0] = 0; 1270 token->RRC[1] = 0; 1271 1272 HEIMDAL_MUTEX_lock(&ctx->ctx_id_mutex); 1273 krb5_auth_con_getlocalseqnumber(context, 1274 ctx->auth_context, 1275 &seq_number); 1276 _gsskrb5_encode_be_om_uint32(0, &token->SND_SEQ[0]); 1277 _gsskrb5_encode_be_om_uint32(seq_number, &token->SND_SEQ[4]); 1278 krb5_auth_con_setlocalseqnumber(context, 1279 ctx->auth_context, 1280 ++seq_number); 1281 HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex); 1282 1283 /* 1284 * If confidentiality is requested, the token header is 1285 * appended to the plaintext before encryption; the resulting 1286 * token is {"header" | encrypt(plaintext | pad | "header")}. 1287 * 1288 * If no confidentiality is requested, the checksum is 1289 * calculated over the plaintext concatenated with the 1290 * token header. 1291 */ 1292 if (ctx->more_flags & LOCAL) { 1293 usage = KRB5_KU_USAGE_INITIATOR_SEAL; 1294 } else { 1295 usage = KRB5_KU_USAGE_ACCEPTOR_SEAL; 1296 } 1297 1298 if (conf_req_flag) { 1299 /* 1300 * Any necessary padding is added here to ensure that the 1301 * encrypted token header is always at the end of the 1302 * ciphertext. 1303 * 1304 * The specification does not require that the padding 1305 * bytes are initialized. 1306 */ 1307 p += sizeof(*token); 1308 memcpy(p, input_message_buffer->value, input_message_buffer->length); 1309 memset(p + input_message_buffer->length, 0xFF, padlength); 1310 memcpy(p + input_message_buffer->length + padlength, 1311 token, sizeof(*token)); 1312 1313 ret = krb5_encrypt(context, ctx->crypto, 1314 usage, p, 1315 input_message_buffer->length + padlength + 1316 sizeof(*token), 1317 &cipher); 1318 if (ret != 0) { 1319 *minor_status = ret; 1320 _gsskrb5_release_buffer(minor_status, output_message_buffer); 1321 return GSS_S_FAILURE; 1322 } 1323 assert(sizeof(*token) + cipher.length == wrapped_len); 1324 token->RRC[0] = (rrc >> 8) & 0xFF; 1325 token->RRC[1] = (rrc >> 0) & 0xFF; 1326 1327 /* 1328 * this is really ugly, but needed against windows 1329 * for DCERPC, as windows rotates by EC+RRC. 1330 */ 1331 if (IS_DCE_STYLE(ctx)) { 1332 ret = rrc_rotate(cipher.data, cipher.length, rrc+padlength, FALSE); 1333 } else { 1334 ret = rrc_rotate(cipher.data, cipher.length, rrc, FALSE); 1335 } 1336 if (ret != 0) { 1337 *minor_status = ret; 1338 _gsskrb5_release_buffer(minor_status, output_message_buffer); 1339 return GSS_S_FAILURE; 1340 } 1341 memcpy(p, cipher.data, cipher.length); 1342 krb5_data_free(&cipher); 1343 } else { 1344 char *buf; 1345 Checksum cksum; 1346 1347 buf = malloc(input_message_buffer->length + sizeof(*token)); 1348 if (buf == NULL) { 1349 *minor_status = ENOMEM; 1350 _gsskrb5_release_buffer(minor_status, output_message_buffer); 1351 return GSS_S_FAILURE; 1352 } 1353 memcpy(buf, input_message_buffer->value, input_message_buffer->length); 1354 memcpy(buf + input_message_buffer->length, token, sizeof(*token)); 1355 1356 ret = krb5_create_checksum(context, ctx->crypto, 1357 usage, 0, buf, 1358 input_message_buffer->length + 1359 sizeof(*token), 1360 &cksum); 1361 if (ret != 0) { 1362 *minor_status = ret; 1363 _gsskrb5_release_buffer(minor_status, output_message_buffer); 1364 free(buf); 1365 return GSS_S_FAILURE; 1366 } 1367 1368 free(buf); 1369 1370 assert(cksum.checksum.length == cksumsize); 1371 token->EC[0] = (cksum.checksum.length >> 8) & 0xFF; 1372 token->EC[1] = (cksum.checksum.length >> 0) & 0xFF; 1373 token->RRC[0] = (rrc >> 8) & 0xFF; 1374 token->RRC[1] = (rrc >> 0) & 0xFF; 1375 1376 p += sizeof(*token); 1377 memcpy(p, input_message_buffer->value, input_message_buffer->length); 1378 memcpy(p + input_message_buffer->length, 1379 cksum.checksum.data, cksum.checksum.length); 1380 1381 ret = rrc_rotate(p, 1382 input_message_buffer->length + cksum.checksum.length, rrc, FALSE); 1383 if (ret != 0) { 1384 *minor_status = ret; 1385 _gsskrb5_release_buffer(minor_status, output_message_buffer); 1386 free_Checksum(&cksum); 1387 return GSS_S_FAILURE; 1388 } 1389 free_Checksum(&cksum); 1390 } 1391 1392 if (conf_state != NULL) { 1393 *conf_state = conf_req_flag; 1394 } 1395 1396 *minor_status = 0; 1397 return GSS_S_COMPLETE; 1398 } 1399 1400 OM_uint32 _gssapi_unwrap_cfx(OM_uint32 *minor_status, 1401 const gsskrb5_ctx ctx, 1402 krb5_context context, 1403 const gss_buffer_t input_message_buffer, 1404 gss_buffer_t output_message_buffer, 1405 int *conf_state, 1406 gss_qop_t *qop_state) 1407 { 1408 gss_cfx_wrap_token token; 1409 u_char token_flags; 1410 krb5_error_code ret; 1411 unsigned usage; 1412 krb5_data data; 1413 uint16_t ec, rrc; 1414 OM_uint32 seq_number_lo, seq_number_hi; 1415 size_t len; 1416 u_char *p; 1417 1418 *minor_status = 0; 1419 1420 if (input_message_buffer->length < sizeof(*token)) { 1421 return GSS_S_DEFECTIVE_TOKEN; 1422 } 1423 1424 p = input_message_buffer->value; 1425 1426 token = (gss_cfx_wrap_token)p; 1427 1428 if (token->TOK_ID[0] != 0x05 || token->TOK_ID[1] != 0x04) { 1429 return GSS_S_DEFECTIVE_TOKEN; 1430 } 1431 1432 /* Ignore unknown flags */ 1433 token_flags = token->Flags & 1434 (CFXSentByAcceptor | CFXSealed | CFXAcceptorSubkey); 1435 1436 if (token_flags & CFXSentByAcceptor) { 1437 if ((ctx->more_flags & LOCAL) == 0) 1438 return GSS_S_DEFECTIVE_TOKEN; 1439 } 1440 1441 if (ctx->more_flags & ACCEPTOR_SUBKEY) { 1442 if ((token_flags & CFXAcceptorSubkey) == 0) 1443 return GSS_S_DEFECTIVE_TOKEN; 1444 } else { 1445 if (token_flags & CFXAcceptorSubkey) 1446 return GSS_S_DEFECTIVE_TOKEN; 1447 } 1448 1449 if (token->Filler != 0xFF) { 1450 return GSS_S_DEFECTIVE_TOKEN; 1451 } 1452 1453 if (conf_state != NULL) { 1454 *conf_state = (token_flags & CFXSealed) ? 1 : 0; 1455 } 1456 1457 ec = (token->EC[0] << 8) | token->EC[1]; 1458 rrc = (token->RRC[0] << 8) | token->RRC[1]; 1459 1460 /* 1461 * Check sequence number 1462 */ 1463 _gsskrb5_decode_be_om_uint32(&token->SND_SEQ[0], &seq_number_hi); 1464 _gsskrb5_decode_be_om_uint32(&token->SND_SEQ[4], &seq_number_lo); 1465 if (seq_number_hi) { 1466 /* no support for 64-bit sequence numbers */ 1467 *minor_status = ERANGE; 1468 return GSS_S_UNSEQ_TOKEN; 1469 } 1470 1471 HEIMDAL_MUTEX_lock(&ctx->ctx_id_mutex); 1472 ret = _gssapi_msg_order_check(ctx->order, seq_number_lo); 1473 if (ret != 0) { 1474 *minor_status = 0; 1475 HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex); 1476 _gsskrb5_release_buffer(minor_status, output_message_buffer); 1477 return ret; 1478 } 1479 HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex); 1480 1481 /* 1482 * Decrypt and/or verify checksum 1483 */ 1484 1485 if (ctx->more_flags & LOCAL) { 1486 usage = KRB5_KU_USAGE_ACCEPTOR_SEAL; 1487 } else { 1488 usage = KRB5_KU_USAGE_INITIATOR_SEAL; 1489 } 1490 1491 p += sizeof(*token); 1492 len = input_message_buffer->length; 1493 len -= (p - (u_char *)input_message_buffer->value); 1494 1495 if (token_flags & CFXSealed) { 1496 /* 1497 * this is really ugly, but needed against windows 1498 * for DCERPC, as windows rotates by EC+RRC. 1499 */ 1500 if (IS_DCE_STYLE(ctx)) { 1501 *minor_status = rrc_rotate(p, len, rrc+ec, TRUE); 1502 } else { 1503 *minor_status = rrc_rotate(p, len, rrc, TRUE); 1504 } 1505 if (*minor_status != 0) { 1506 return GSS_S_FAILURE; 1507 } 1508 1509 ret = krb5_decrypt(context, ctx->crypto, usage, 1510 p, len, &data); 1511 if (ret != 0) { 1512 *minor_status = ret; 1513 return GSS_S_BAD_MIC; 1514 } 1515 1516 /* Check that there is room for the pad and token header */ 1517 if (data.length < ec + sizeof(*token)) { 1518 krb5_data_free(&data); 1519 return GSS_S_DEFECTIVE_TOKEN; 1520 } 1521 p = data.data; 1522 p += data.length - sizeof(*token); 1523 1524 /* RRC is unprotected; don't modify input buffer */ 1525 ((gss_cfx_wrap_token)p)->RRC[0] = token->RRC[0]; 1526 ((gss_cfx_wrap_token)p)->RRC[1] = token->RRC[1]; 1527 1528 /* Check the integrity of the header */ 1529 if (ct_memcmp(p, token, sizeof(*token)) != 0) { 1530 krb5_data_free(&data); 1531 return GSS_S_BAD_MIC; 1532 } 1533 1534 output_message_buffer->value = data.data; 1535 output_message_buffer->length = data.length - ec - sizeof(*token); 1536 } else { 1537 Checksum cksum; 1538 1539 /* Rotate by RRC; bogus to do this in-place XXX */ 1540 *minor_status = rrc_rotate(p, len, rrc, TRUE); 1541 if (*minor_status != 0) { 1542 return GSS_S_FAILURE; 1543 } 1544 1545 /* Determine checksum type */ 1546 ret = krb5_crypto_get_checksum_type(context, 1547 ctx->crypto, 1548 &cksum.cksumtype); 1549 if (ret != 0) { 1550 *minor_status = ret; 1551 return GSS_S_FAILURE; 1552 } 1553 1554 cksum.checksum.length = ec; 1555 1556 /* Check we have at least as much data as the checksum */ 1557 if (len < cksum.checksum.length) { 1558 *minor_status = ERANGE; 1559 return GSS_S_BAD_MIC; 1560 } 1561 1562 /* Length now is of the plaintext only, no checksum */ 1563 len -= cksum.checksum.length; 1564 cksum.checksum.data = p + len; 1565 1566 output_message_buffer->length = len; /* for later */ 1567 output_message_buffer->value = malloc(len + sizeof(*token)); 1568 if (output_message_buffer->value == NULL) { 1569 *minor_status = ENOMEM; 1570 return GSS_S_FAILURE; 1571 } 1572 1573 /* Checksum is over (plaintext-data | "header") */ 1574 memcpy(output_message_buffer->value, p, len); 1575 memcpy((u_char *)output_message_buffer->value + len, 1576 token, sizeof(*token)); 1577 1578 /* EC is not included in checksum calculation */ 1579 token = (gss_cfx_wrap_token)((u_char *)output_message_buffer->value + 1580 len); 1581 token->EC[0] = 0; 1582 token->EC[1] = 0; 1583 token->RRC[0] = 0; 1584 token->RRC[1] = 0; 1585 1586 ret = krb5_verify_checksum(context, ctx->crypto, 1587 usage, 1588 output_message_buffer->value, 1589 len + sizeof(*token), 1590 &cksum); 1591 if (ret != 0) { 1592 *minor_status = ret; 1593 _gsskrb5_release_buffer(minor_status, output_message_buffer); 1594 return GSS_S_BAD_MIC; 1595 } 1596 } 1597 1598 if (qop_state != NULL) { 1599 *qop_state = GSS_C_QOP_DEFAULT; 1600 } 1601 1602 *minor_status = 0; 1603 return GSS_S_COMPLETE; 1604 } 1605 1606 OM_uint32 _gssapi_mic_cfx(OM_uint32 *minor_status, 1607 const gsskrb5_ctx ctx, 1608 krb5_context context, 1609 gss_qop_t qop_req, 1610 const gss_buffer_t message_buffer, 1611 gss_buffer_t message_token) 1612 { 1613 gss_cfx_mic_token token; 1614 krb5_error_code ret; 1615 unsigned usage; 1616 Checksum cksum; 1617 u_char *buf; 1618 size_t len; 1619 int32_t seq_number; 1620 1621 len = message_buffer->length + sizeof(*token); 1622 buf = malloc(len); 1623 if (buf == NULL) { 1624 *minor_status = ENOMEM; 1625 return GSS_S_FAILURE; 1626 } 1627 1628 memcpy(buf, message_buffer->value, message_buffer->length); 1629 1630 token = (gss_cfx_mic_token)(buf + message_buffer->length); 1631 token->TOK_ID[0] = 0x04; 1632 token->TOK_ID[1] = 0x04; 1633 token->Flags = 0; 1634 if ((ctx->more_flags & LOCAL) == 0) 1635 token->Flags |= CFXSentByAcceptor; 1636 if (ctx->more_flags & ACCEPTOR_SUBKEY) 1637 token->Flags |= CFXAcceptorSubkey; 1638 memset(token->Filler, 0xFF, 5); 1639 1640 HEIMDAL_MUTEX_lock(&ctx->ctx_id_mutex); 1641 krb5_auth_con_getlocalseqnumber(context, 1642 ctx->auth_context, 1643 &seq_number); 1644 _gsskrb5_encode_be_om_uint32(0, &token->SND_SEQ[0]); 1645 _gsskrb5_encode_be_om_uint32(seq_number, &token->SND_SEQ[4]); 1646 krb5_auth_con_setlocalseqnumber(context, 1647 ctx->auth_context, 1648 ++seq_number); 1649 HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex); 1650 1651 if (ctx->more_flags & LOCAL) { 1652 usage = KRB5_KU_USAGE_INITIATOR_SIGN; 1653 } else { 1654 usage = KRB5_KU_USAGE_ACCEPTOR_SIGN; 1655 } 1656 1657 ret = krb5_create_checksum(context, ctx->crypto, 1658 usage, 0, buf, len, &cksum); 1659 if (ret != 0) { 1660 *minor_status = ret; 1661 free(buf); 1662 return GSS_S_FAILURE; 1663 } 1664 1665 /* Determine MIC length */ 1666 message_token->length = sizeof(*token) + cksum.checksum.length; 1667 message_token->value = malloc(message_token->length); 1668 if (message_token->value == NULL) { 1669 *minor_status = ENOMEM; 1670 free_Checksum(&cksum); 1671 free(buf); 1672 return GSS_S_FAILURE; 1673 } 1674 1675 /* Token is { "header" | get_mic("header" | plaintext-data) } */ 1676 memcpy(message_token->value, token, sizeof(*token)); 1677 memcpy((u_char *)message_token->value + sizeof(*token), 1678 cksum.checksum.data, cksum.checksum.length); 1679 1680 free_Checksum(&cksum); 1681 free(buf); 1682 1683 *minor_status = 0; 1684 return GSS_S_COMPLETE; 1685 } 1686 1687 OM_uint32 _gssapi_verify_mic_cfx(OM_uint32 *minor_status, 1688 const gsskrb5_ctx ctx, 1689 krb5_context context, 1690 const gss_buffer_t message_buffer, 1691 const gss_buffer_t token_buffer, 1692 gss_qop_t *qop_state) 1693 { 1694 gss_cfx_mic_token token; 1695 u_char token_flags; 1696 krb5_error_code ret; 1697 unsigned usage; 1698 OM_uint32 seq_number_lo, seq_number_hi; 1699 u_char *buf, *p; 1700 Checksum cksum; 1701 1702 *minor_status = 0; 1703 1704 if (token_buffer->length < sizeof(*token)) { 1705 return GSS_S_DEFECTIVE_TOKEN; 1706 } 1707 1708 p = token_buffer->value; 1709 1710 token = (gss_cfx_mic_token)p; 1711 1712 if (token->TOK_ID[0] != 0x04 || token->TOK_ID[1] != 0x04) { 1713 return GSS_S_DEFECTIVE_TOKEN; 1714 } 1715 1716 /* Ignore unknown flags */ 1717 token_flags = token->Flags & (CFXSentByAcceptor | CFXAcceptorSubkey); 1718 1719 if (token_flags & CFXSentByAcceptor) { 1720 if ((ctx->more_flags & LOCAL) == 0) 1721 return GSS_S_DEFECTIVE_TOKEN; 1722 } 1723 if (ctx->more_flags & ACCEPTOR_SUBKEY) { 1724 if ((token_flags & CFXAcceptorSubkey) == 0) 1725 return GSS_S_DEFECTIVE_TOKEN; 1726 } else { 1727 if (token_flags & CFXAcceptorSubkey) 1728 return GSS_S_DEFECTIVE_TOKEN; 1729 } 1730 1731 if (ct_memcmp(token->Filler, "\xff\xff\xff\xff\xff", 5) != 0) { 1732 return GSS_S_DEFECTIVE_TOKEN; 1733 } 1734 1735 /* 1736 * Check sequence number 1737 */ 1738 _gsskrb5_decode_be_om_uint32(&token->SND_SEQ[0], &seq_number_hi); 1739 _gsskrb5_decode_be_om_uint32(&token->SND_SEQ[4], &seq_number_lo); 1740 if (seq_number_hi) { 1741 *minor_status = ERANGE; 1742 return GSS_S_UNSEQ_TOKEN; 1743 } 1744 1745 HEIMDAL_MUTEX_lock(&ctx->ctx_id_mutex); 1746 ret = _gssapi_msg_order_check(ctx->order, seq_number_lo); 1747 if (ret != 0) { 1748 *minor_status = 0; 1749 HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex); 1750 return ret; 1751 } 1752 HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex); 1753 1754 /* 1755 * Verify checksum 1756 */ 1757 ret = krb5_crypto_get_checksum_type(context, ctx->crypto, 1758 &cksum.cksumtype); 1759 if (ret != 0) { 1760 *minor_status = ret; 1761 return GSS_S_FAILURE; 1762 } 1763 1764 cksum.checksum.data = p + sizeof(*token); 1765 cksum.checksum.length = token_buffer->length - sizeof(*token); 1766 1767 if (ctx->more_flags & LOCAL) { 1768 usage = KRB5_KU_USAGE_ACCEPTOR_SIGN; 1769 } else { 1770 usage = KRB5_KU_USAGE_INITIATOR_SIGN; 1771 } 1772 1773 buf = malloc(message_buffer->length + sizeof(*token)); 1774 if (buf == NULL) { 1775 *minor_status = ENOMEM; 1776 return GSS_S_FAILURE; 1777 } 1778 memcpy(buf, message_buffer->value, message_buffer->length); 1779 memcpy(buf + message_buffer->length, token, sizeof(*token)); 1780 1781 ret = krb5_verify_checksum(context, ctx->crypto, 1782 usage, 1783 buf, 1784 sizeof(*token) + message_buffer->length, 1785 &cksum); 1786 if (ret != 0) { 1787 *minor_status = ret; 1788 free(buf); 1789 return GSS_S_BAD_MIC; 1790 } 1791 1792 free(buf); 1793 1794 if (qop_state != NULL) { 1795 *qop_state = GSS_C_QOP_DEFAULT; 1796 } 1797 1798 return GSS_S_COMPLETE; 1799 } 1800
Indexes created Mon Jun 15 00:25:07 UTC 2026