1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2008 Isilon Inc http://www.isilon.com/ 5 * Authors: Doug Rabson <dfr@rabson.org> 6 * Developed with Red Inc: Alfred Perlstein <alfred@freebsd.org> 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 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 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30 #include <sys/cdefs.h> 31 #include "opt_inet6.h" 32 33 #include <sys/param.h> 34 #include <sys/kernel.h> 35 #include <sys/kobj.h> 36 #include <sys/lock.h> 37 #include <sys/malloc.h> 38 #include <sys/mbuf.h> 39 #include <sys/module.h> 40 #include <sys/mutex.h> 41 #include <kgssapi/gssapi.h> 42 #include <kgssapi/gssapi_impl.h> 43 44 #include "kgss_if.h" 45 #include "kcrypto.h" 46 47 #define GSS_TOKEN_SENT_BY_ACCEPTOR 1 48 #define GSS_TOKEN_SEALED 2 49 #define GSS_TOKEN_ACCEPTOR_SUBKEY 4 50 51 static gss_OID_desc krb5_mech_oid = 52 {9, (void *) "\x2a\x86\x48\x86\xf7\x12\x01\x02\x02" }; 53 54 struct krb5_data { 55 size_t kd_length; 56 void *kd_data; 57 }; 58 59 struct krb5_keyblock { 60 uint16_t kk_type; /* encryption type */ 61 struct krb5_data kk_key; /* key data */ 62 }; 63 64 struct krb5_address { 65 uint16_t ka_type; 66 struct krb5_data ka_addr; 67 }; 68 69 /* 70 * The km_elem array is ordered so that the highest received sequence 71 * number is listed first. 72 */ 73 struct krb5_msg_order { 74 uint32_t km_flags; 75 uint32_t km_start; 76 uint32_t km_length; 77 uint32_t km_jitter_window; 78 uint32_t km_first_seq; 79 uint32_t *km_elem; 80 }; 81 82 struct krb5_context { 83 struct _gss_ctx_id_t kc_common; 84 struct mtx kc_lock; 85 uint32_t kc_ac_flags; 86 uint32_t kc_ctx_flags; 87 uint32_t kc_more_flags; 88 #define LOCAL 1 89 #define OPEN 2 90 #define COMPAT_OLD_DES3 4 91 #define COMPAT_OLD_DES3_SELECTED 8 92 #define ACCEPTOR_SUBKEY 16 93 struct krb5_address kc_local_address; 94 struct krb5_address kc_remote_address; 95 uint16_t kc_local_port; 96 uint16_t kc_remote_port; 97 struct krb5_keyblock kc_keyblock; 98 struct krb5_keyblock kc_local_subkey; 99 struct krb5_keyblock kc_remote_subkey; 100 volatile uint32_t kc_local_seqnumber; 101 uint32_t kc_remote_seqnumber; 102 uint32_t kc_keytype; 103 uint32_t kc_cksumtype; 104 struct krb5_data kc_source_name; 105 struct krb5_data kc_target_name; 106 uint32_t kc_lifetime; 107 struct krb5_msg_order kc_msg_order; 108 struct krb5_key_state *kc_tokenkey; 109 struct krb5_key_state *kc_encryptkey; 110 struct krb5_key_state *kc_checksumkey; 111 112 struct krb5_key_state *kc_send_seal_Ke; 113 struct krb5_key_state *kc_send_seal_Ki; 114 struct krb5_key_state *kc_send_seal_Kc; 115 struct krb5_key_state *kc_send_sign_Kc; 116 117 struct krb5_key_state *kc_recv_seal_Ke; 118 struct krb5_key_state *kc_recv_seal_Ki; 119 struct krb5_key_state *kc_recv_seal_Kc; 120 struct krb5_key_state *kc_recv_sign_Kc; 121 }; 122 123 static uint16_t 124 get_uint16(const uint8_t **pp, size_t *lenp) 125 { 126 const uint8_t *p = *pp; 127 uint16_t v; 128 129 if (*lenp < 2) 130 return (0); 131 132 v = (p[0] << 8) | p[1]; 133 *pp = p + 2; 134 *lenp = *lenp - 2; 135 136 return (v); 137 } 138 139 static uint32_t 140 get_uint32(const uint8_t **pp, size_t *lenp) 141 { 142 const uint8_t *p = *pp; 143 uint32_t v; 144 145 if (*lenp < 4) 146 return (0); 147 148 v = (p[0] << 24) | (p[1] << 16) | (p[2] << 8) | p[3]; 149 *pp = p + 4; 150 *lenp = *lenp - 4; 151 152 return (v); 153 } 154 155 static void 156 get_data(const uint8_t **pp, size_t *lenp, struct krb5_data *dp) 157 { 158 size_t sz = get_uint32(pp, lenp); 159 160 dp->kd_length = sz; 161 dp->kd_data = malloc(sz, M_GSSAPI, M_WAITOK); 162 163 if (*lenp < sz) 164 sz = *lenp; 165 bcopy(*pp, dp->kd_data, sz); 166 (*pp) += sz; 167 (*lenp) -= sz; 168 } 169 170 static void 171 delete_data(struct krb5_data *dp) 172 { 173 if (dp->kd_data) { 174 free(dp->kd_data, M_GSSAPI); 175 dp->kd_length = 0; 176 dp->kd_data = NULL; 177 } 178 } 179 180 static void 181 get_address(const uint8_t **pp, size_t *lenp, struct krb5_address *ka) 182 { 183 184 ka->ka_type = get_uint16(pp, lenp); 185 get_data(pp, lenp, &ka->ka_addr); 186 } 187 188 static void 189 delete_address(struct krb5_address *ka) 190 { 191 delete_data(&ka->ka_addr); 192 } 193 194 static void 195 get_keyblock(const uint8_t **pp, size_t *lenp, struct krb5_keyblock *kk) 196 { 197 198 kk->kk_type = get_uint16(pp, lenp); 199 get_data(pp, lenp, &kk->kk_key); 200 } 201 202 static void 203 delete_keyblock(struct krb5_keyblock *kk) 204 { 205 if (kk->kk_key.kd_data) 206 bzero(kk->kk_key.kd_data, kk->kk_key.kd_length); 207 delete_data(&kk->kk_key); 208 } 209 210 static void 211 copy_key(struct krb5_keyblock *from, struct krb5_keyblock **to) 212 { 213 214 if (from->kk_key.kd_length) 215 *to = from; 216 else 217 *to = NULL; 218 } 219 220 /* 221 * Return non-zero if we are initiator. 222 */ 223 static __inline int 224 is_initiator(struct krb5_context *kc) 225 { 226 return (kc->kc_more_flags & LOCAL); 227 } 228 229 /* 230 * Return non-zero if we are acceptor. 231 */ 232 static __inline int 233 is_acceptor(struct krb5_context *kc) 234 { 235 return !(kc->kc_more_flags & LOCAL); 236 } 237 238 static void 239 get_initiator_subkey(struct krb5_context *kc, struct krb5_keyblock **kdp) 240 { 241 242 if (is_initiator(kc)) 243 copy_key(&kc->kc_local_subkey, kdp); 244 else 245 copy_key(&kc->kc_remote_subkey, kdp); 246 if (!*kdp) 247 copy_key(&kc->kc_keyblock, kdp); 248 } 249 250 static void 251 get_acceptor_subkey(struct krb5_context *kc, struct krb5_keyblock **kdp) 252 { 253 254 if (is_initiator(kc)) 255 copy_key(&kc->kc_remote_subkey, kdp); 256 else 257 copy_key(&kc->kc_local_subkey, kdp); 258 } 259 260 static OM_uint32 261 get_keys(struct krb5_context *kc) 262 { 263 struct krb5_keyblock *keydata; 264 struct krb5_encryption_class *ec; 265 struct krb5_key_state *key; 266 int etype; 267 268 keydata = NULL; 269 get_acceptor_subkey(kc, &keydata); 270 if (!keydata) 271 if ((kc->kc_more_flags & ACCEPTOR_SUBKEY) == 0) 272 get_initiator_subkey(kc, &keydata); 273 if (!keydata) 274 return (GSS_S_FAILURE); 275 276 /* 277 * GSS-API treats all DES etypes the same and all DES3 etypes 278 * the same. 279 */ 280 switch (keydata->kk_type) { 281 case ETYPE_DES_CBC_CRC: 282 case ETYPE_DES_CBC_MD4: 283 case ETYPE_DES_CBC_MD5: 284 etype = ETYPE_DES_CBC_CRC; 285 break; 286 287 case ETYPE_DES3_CBC_MD5: 288 case ETYPE_DES3_CBC_SHA1: 289 case ETYPE_OLD_DES3_CBC_SHA1: 290 etype = ETYPE_DES3_CBC_SHA1; 291 break; 292 293 default: 294 etype = keydata->kk_type; 295 } 296 297 ec = krb5_find_encryption_class(etype); 298 if (!ec) 299 return (GSS_S_FAILURE); 300 301 key = krb5_create_key(ec); 302 krb5_set_key(key, keydata->kk_key.kd_data); 303 kc->kc_tokenkey = key; 304 305 switch (etype) { 306 case ETYPE_DES_CBC_CRC: 307 case ETYPE_ARCFOUR_HMAC_MD5: 308 case ETYPE_ARCFOUR_HMAC_MD5_56: { 309 /* 310 * Single DES and ARCFOUR uses a 'derived' key (XOR 311 * with 0xf0) for encrypting wrap tokens. The original 312 * key is used for checksums and sequence numbers. 313 */ 314 struct krb5_key_state *ekey; 315 uint8_t *ekp, *kp; 316 int i; 317 318 ekey = krb5_create_key(ec); 319 ekp = ekey->ks_key; 320 kp = key->ks_key; 321 for (i = 0; i < ec->ec_keylen; i++) 322 ekp[i] = kp[i] ^ 0xf0; 323 krb5_set_key(ekey, ekp); 324 kc->kc_encryptkey = ekey; 325 refcount_acquire(&key->ks_refs); 326 kc->kc_checksumkey = key; 327 break; 328 } 329 330 case ETYPE_DES3_CBC_SHA1: 331 /* 332 * Triple DES uses a RFC 3961 style derived key with 333 * usage number KG_USAGE_SIGN for checksums. The 334 * original key is used for encryption and sequence 335 * numbers. 336 */ 337 kc->kc_checksumkey = krb5_get_checksum_key(key, KG_USAGE_SIGN); 338 refcount_acquire(&key->ks_refs); 339 kc->kc_encryptkey = key; 340 break; 341 342 default: 343 /* 344 * We need eight derived keys four for sending and 345 * four for receiving. 346 */ 347 if (is_initiator(kc)) { 348 /* 349 * We are initiator. 350 */ 351 kc->kc_send_seal_Ke = krb5_get_encryption_key(key, 352 KG_USAGE_INITIATOR_SEAL); 353 kc->kc_send_seal_Ki = krb5_get_integrity_key(key, 354 KG_USAGE_INITIATOR_SEAL); 355 kc->kc_send_seal_Kc = krb5_get_checksum_key(key, 356 KG_USAGE_INITIATOR_SEAL); 357 kc->kc_send_sign_Kc = krb5_get_checksum_key(key, 358 KG_USAGE_INITIATOR_SIGN); 359 360 kc->kc_recv_seal_Ke = krb5_get_encryption_key(key, 361 KG_USAGE_ACCEPTOR_SEAL); 362 kc->kc_recv_seal_Ki = krb5_get_integrity_key(key, 363 KG_USAGE_ACCEPTOR_SEAL); 364 kc->kc_recv_seal_Kc = krb5_get_checksum_key(key, 365 KG_USAGE_ACCEPTOR_SEAL); 366 kc->kc_recv_sign_Kc = krb5_get_checksum_key(key, 367 KG_USAGE_ACCEPTOR_SIGN); 368 } else { 369 /* 370 * We are acceptor. 371 */ 372 kc->kc_send_seal_Ke = krb5_get_encryption_key(key, 373 KG_USAGE_ACCEPTOR_SEAL); 374 kc->kc_send_seal_Ki = krb5_get_integrity_key(key, 375 KG_USAGE_ACCEPTOR_SEAL); 376 kc->kc_send_seal_Kc = krb5_get_checksum_key(key, 377 KG_USAGE_ACCEPTOR_SEAL); 378 kc->kc_send_sign_Kc = krb5_get_checksum_key(key, 379 KG_USAGE_ACCEPTOR_SIGN); 380 381 kc->kc_recv_seal_Ke = krb5_get_encryption_key(key, 382 KG_USAGE_INITIATOR_SEAL); 383 kc->kc_recv_seal_Ki = krb5_get_integrity_key(key, 384 KG_USAGE_INITIATOR_SEAL); 385 kc->kc_recv_seal_Kc = krb5_get_checksum_key(key, 386 KG_USAGE_INITIATOR_SEAL); 387 kc->kc_recv_sign_Kc = krb5_get_checksum_key(key, 388 KG_USAGE_INITIATOR_SIGN); 389 } 390 break; 391 } 392 393 return (GSS_S_COMPLETE); 394 } 395 396 static void 397 krb5_init(gss_ctx_id_t ctx) 398 { 399 struct krb5_context *kc = (struct krb5_context *)ctx; 400 401 mtx_init(&kc->kc_lock, "krb5 gss lock", NULL, MTX_DEF); 402 } 403 404 static OM_uint32 405 krb5_import(gss_ctx_id_t ctx, 406 enum sec_context_format format, 407 const gss_buffer_t context_token) 408 { 409 struct krb5_context *kc = (struct krb5_context *)ctx; 410 OM_uint32 res; 411 const uint8_t *p = (const uint8_t *) context_token->value; 412 size_t len = context_token->length; 413 uint32_t flags; 414 int i; 415 416 /* 417 * We support heimdal 0.6 and heimdal 1.1 418 */ 419 if (format != KGSS_HEIMDAL_0_6 && format != KGSS_HEIMDAL_1_1) 420 return (GSS_S_DEFECTIVE_TOKEN); 421 422 #define SC_LOCAL_ADDRESS 1 423 #define SC_REMOTE_ADDRESS 2 424 #define SC_KEYBLOCK 4 425 #define SC_LOCAL_SUBKEY 8 426 #define SC_REMOTE_SUBKEY 16 427 428 /* 429 * Ensure that the token starts with krb5 oid. 430 */ 431 if (p[0] != 0x00 || p[1] != krb5_mech_oid.length 432 || len < krb5_mech_oid.length + 2 433 || bcmp(krb5_mech_oid.elements, p + 2, 434 krb5_mech_oid.length)) 435 return (GSS_S_DEFECTIVE_TOKEN); 436 p += krb5_mech_oid.length + 2; 437 len -= krb5_mech_oid.length + 2; 438 439 flags = get_uint32(&p, &len); 440 kc->kc_ac_flags = get_uint32(&p, &len); 441 if (flags & SC_LOCAL_ADDRESS) 442 get_address(&p, &len, &kc->kc_local_address); 443 if (flags & SC_REMOTE_ADDRESS) 444 get_address(&p, &len, &kc->kc_remote_address); 445 kc->kc_local_port = get_uint16(&p, &len); 446 kc->kc_remote_port = get_uint16(&p, &len); 447 if (flags & SC_KEYBLOCK) 448 get_keyblock(&p, &len, &kc->kc_keyblock); 449 if (flags & SC_LOCAL_SUBKEY) 450 get_keyblock(&p, &len, &kc->kc_local_subkey); 451 if (flags & SC_REMOTE_SUBKEY) 452 get_keyblock(&p, &len, &kc->kc_remote_subkey); 453 kc->kc_local_seqnumber = get_uint32(&p, &len); 454 kc->kc_remote_seqnumber = get_uint32(&p, &len); 455 kc->kc_keytype = get_uint32(&p, &len); 456 kc->kc_cksumtype = get_uint32(&p, &len); 457 get_data(&p, &len, &kc->kc_source_name); 458 get_data(&p, &len, &kc->kc_target_name); 459 kc->kc_ctx_flags = get_uint32(&p, &len); 460 kc->kc_more_flags = get_uint32(&p, &len); 461 kc->kc_lifetime = get_uint32(&p, &len); 462 /* 463 * Heimdal 1.1 adds the message order stuff. 464 */ 465 if (format == KGSS_HEIMDAL_1_1) { 466 kc->kc_msg_order.km_flags = get_uint32(&p, &len); 467 kc->kc_msg_order.km_start = get_uint32(&p, &len); 468 kc->kc_msg_order.km_length = get_uint32(&p, &len); 469 kc->kc_msg_order.km_jitter_window = get_uint32(&p, &len); 470 kc->kc_msg_order.km_first_seq = get_uint32(&p, &len); 471 kc->kc_msg_order.km_elem = 472 malloc(kc->kc_msg_order.km_jitter_window * sizeof(uint32_t), 473 M_GSSAPI, M_WAITOK); 474 for (i = 0; i < kc->kc_msg_order.km_jitter_window; i++) 475 kc->kc_msg_order.km_elem[i] = get_uint32(&p, &len); 476 } else { 477 kc->kc_msg_order.km_flags = 0; 478 } 479 480 res = get_keys(kc); 481 if (GSS_ERROR(res)) 482 return (res); 483 484 /* 485 * We don't need these anymore. 486 */ 487 delete_keyblock(&kc->kc_keyblock); 488 delete_keyblock(&kc->kc_local_subkey); 489 delete_keyblock(&kc->kc_remote_subkey); 490 491 return (GSS_S_COMPLETE); 492 } 493 494 static void 495 krb5_delete(gss_ctx_id_t ctx, gss_buffer_t output_token) 496 { 497 struct krb5_context *kc = (struct krb5_context *)ctx; 498 499 delete_address(&kc->kc_local_address); 500 delete_address(&kc->kc_remote_address); 501 delete_keyblock(&kc->kc_keyblock); 502 delete_keyblock(&kc->kc_local_subkey); 503 delete_keyblock(&kc->kc_remote_subkey); 504 delete_data(&kc->kc_source_name); 505 delete_data(&kc->kc_target_name); 506 if (kc->kc_msg_order.km_elem) 507 free(kc->kc_msg_order.km_elem, M_GSSAPI); 508 if (output_token) { 509 output_token->length = 0; 510 output_token->value = NULL; 511 } 512 if (kc->kc_tokenkey) { 513 krb5_free_key(kc->kc_tokenkey); 514 if (kc->kc_encryptkey) { 515 krb5_free_key(kc->kc_encryptkey); 516 krb5_free_key(kc->kc_checksumkey); 517 } else { 518 krb5_free_key(kc->kc_send_seal_Ke); 519 krb5_free_key(kc->kc_send_seal_Ki); 520 krb5_free_key(kc->kc_send_seal_Kc); 521 krb5_free_key(kc->kc_send_sign_Kc); 522 krb5_free_key(kc->kc_recv_seal_Ke); 523 krb5_free_key(kc->kc_recv_seal_Ki); 524 krb5_free_key(kc->kc_recv_seal_Kc); 525 krb5_free_key(kc->kc_recv_sign_Kc); 526 } 527 } 528 mtx_destroy(&kc->kc_lock); 529 } 530 531 static gss_OID 532 krb5_mech_type(gss_ctx_id_t ctx) 533 { 534 535 return (&krb5_mech_oid); 536 } 537 538 /* 539 * Make a token with the given type and length (the length includes 540 * the TOK_ID), initialising the token header appropriately. Return a 541 * pointer to the TOK_ID of the token. A new mbuf is allocated with 542 * the framing header plus hlen bytes of space. 543 * 544 * Format is as follows: 545 * 546 * 0x60 [APPLICATION 0] SEQUENCE 547 * DER encoded length length of oid + type + inner token length 548 * 0x06 NN <oid data> OID of mechanism type 549 * TT TT TOK_ID 550 * <inner token> data for inner token 551 * 552 * 1: der encoded length 553 */ 554 static void * 555 krb5_make_token(char tok_id[2], size_t hlen, size_t len, struct mbuf **mp) 556 { 557 size_t inside_len, len_len, tlen; 558 gss_OID oid = &krb5_mech_oid; 559 struct mbuf *m; 560 uint8_t *p; 561 562 inside_len = 2 + oid->length + len; 563 if (inside_len < 128) 564 len_len = 1; 565 else if (inside_len < 0x100) 566 len_len = 2; 567 else if (inside_len < 0x10000) 568 len_len = 3; 569 else if (inside_len < 0x1000000) 570 len_len = 4; 571 else 572 len_len = 5; 573 574 tlen = 1 + len_len + 2 + oid->length + hlen; 575 KASSERT(tlen <= MLEN, ("token head too large")); 576 MGET(m, M_WAITOK, MT_DATA); 577 M_ALIGN(m, tlen); 578 m->m_len = tlen; 579 580 p = (uint8_t *) m->m_data; 581 *p++ = 0x60; 582 switch (len_len) { 583 case 1: 584 *p++ = inside_len; 585 break; 586 case 2: 587 *p++ = 0x81; 588 *p++ = inside_len; 589 break; 590 case 3: 591 *p++ = 0x82; 592 *p++ = inside_len >> 8; 593 *p++ = inside_len; 594 break; 595 case 4: 596 *p++ = 0x83; 597 *p++ = inside_len >> 16; 598 *p++ = inside_len >> 8; 599 *p++ = inside_len; 600 break; 601 case 5: 602 *p++ = 0x84; 603 *p++ = inside_len >> 24; 604 *p++ = inside_len >> 16; 605 *p++ = inside_len >> 8; 606 *p++ = inside_len; 607 break; 608 } 609 610 *p++ = 0x06; 611 *p++ = oid->length; 612 bcopy(oid->elements, p, oid->length); 613 p += oid->length; 614 615 p[0] = tok_id[0]; 616 p[1] = tok_id[1]; 617 618 *mp = m; 619 620 return (p); 621 } 622 623 /* 624 * Verify a token, checking the inner token length and mechanism oid. 625 * pointer to the first byte of the TOK_ID. The length of the 626 * encapsulated data is checked to be at least len bytes; the actual 627 * length of the encapsulated data (including TOK_ID) is returned in 628 * *encap_len. 629 * 630 * If can_pullup is TRUE and the token header is fragmented, we will 631 * rearrange it. 632 * 633 * Format is as follows: 634 * 635 * 0x60 [APPLICATION 0] SEQUENCE 636 * DER encoded length length of oid + type + inner token length 637 * 0x06 NN <oid data> OID of mechanism type 638 * TT TT TOK_ID 639 * <inner token> data for inner token 640 * 641 * 1: der encoded length 642 */ 643 static void * 644 krb5_verify_token(char tok_id[2], size_t len, struct mbuf **mp, 645 size_t *encap_len, bool_t can_pullup) 646 { 647 struct mbuf *m; 648 size_t tlen, hlen, len_len, inside_len; 649 gss_OID oid = &krb5_mech_oid; 650 uint8_t *p; 651 652 m = *mp; 653 tlen = m_length(m, NULL); 654 if (tlen < 2) 655 return (NULL); 656 657 /* 658 * Ensure that at least the framing part of the token is 659 * contigous. 660 */ 661 if (m->m_len < 2) { 662 if (can_pullup) 663 *mp = m = m_pullup(m, 2); 664 else 665 return (NULL); 666 } 667 668 p = m->m_data; 669 670 if (*p++ != 0x60) 671 return (NULL); 672 673 if (*p < 0x80) { 674 inside_len = *p++; 675 len_len = 1; 676 } else { 677 /* 678 * Ensure there is enough space for the DER encoded length. 679 */ 680 len_len = (*p & 0x7f) + 1; 681 if (tlen < len_len + 1) 682 return (NULL); 683 if (m->m_len < len_len + 1) { 684 if (can_pullup) 685 *mp = m = m_pullup(m, len_len + 1); 686 else 687 return (NULL); 688 p = m->m_data + 1; 689 } 690 691 switch (*p++) { 692 case 0x81: 693 inside_len = *p++; 694 break; 695 696 case 0x82: 697 inside_len = (p[0] << 8) | p[1]; 698 p += 2; 699 break; 700 701 case 0x83: 702 inside_len = (p[0] << 16) | (p[1] << 8) | p[2]; 703 p += 3; 704 break; 705 706 case 0x84: 707 inside_len = (p[0] << 24) | (p[1] << 16) 708 | (p[2] << 8) | p[3]; 709 p += 4; 710 break; 711 712 default: 713 return (NULL); 714 } 715 } 716 717 if (tlen != inside_len + len_len + 1) 718 return (NULL); 719 if (inside_len < 2 + oid->length + len) 720 return (NULL); 721 722 /* 723 * Now that we know the value of len_len, we can pullup the 724 * whole header. The header is 1 + len_len + 2 + oid->length + 725 * len bytes. 726 */ 727 hlen = 1 + len_len + 2 + oid->length + len; 728 if (m->m_len < hlen) { 729 if (can_pullup) 730 *mp = m = m_pullup(m, hlen); 731 else 732 return (NULL); 733 p = m->m_data + 1 + len_len; 734 } 735 736 if (*p++ != 0x06) 737 return (NULL); 738 if (*p++ != oid->length) 739 return (NULL); 740 if (bcmp(oid->elements, p, oid->length)) 741 return (NULL); 742 p += oid->length; 743 744 if (p[0] != tok_id[0]) 745 return (NULL); 746 747 if (p[1] != tok_id[1]) 748 return (NULL); 749 750 *encap_len = inside_len - 2 - oid->length; 751 752 return (p); 753 } 754 755 static void 756 krb5_insert_seq(struct krb5_msg_order *mo, uint32_t seq, int index) 757 { 758 int i; 759 760 if (mo->km_length < mo->km_jitter_window) 761 mo->km_length++; 762 763 for (i = mo->km_length - 1; i > index; i--) 764 mo->km_elem[i] = mo->km_elem[i - 1]; 765 mo->km_elem[index] = seq; 766 } 767 768 /* 769 * Check sequence numbers according to RFC 2743 section 1.2.3. 770 */ 771 static OM_uint32 772 krb5_sequence_check(struct krb5_context *kc, uint32_t seq) 773 { 774 OM_uint32 res = GSS_S_FAILURE; 775 struct krb5_msg_order *mo = &kc->kc_msg_order; 776 int check_sequence = mo->km_flags & GSS_C_SEQUENCE_FLAG; 777 int check_replay = mo->km_flags & GSS_C_REPLAY_FLAG; 778 int i; 779 780 mtx_lock(&kc->kc_lock); 781 782 /* 783 * Message is in-sequence with no gap. 784 */ 785 if (mo->km_length == 0 || seq == mo->km_elem[0] + 1) { 786 /* 787 * This message is received in-sequence with no gaps. 788 */ 789 krb5_insert_seq(mo, seq, 0); 790 res = GSS_S_COMPLETE; 791 goto out; 792 } 793 794 if (seq > mo->km_elem[0]) { 795 /* 796 * This message is received in-sequence with a gap. 797 */ 798 krb5_insert_seq(mo, seq, 0); 799 if (check_sequence) 800 res = GSS_S_GAP_TOKEN; 801 else 802 res = GSS_S_COMPLETE; 803 goto out; 804 } 805 806 if (seq < mo->km_elem[mo->km_length - 1]) { 807 if (check_replay && !check_sequence) 808 res = GSS_S_OLD_TOKEN; 809 else 810 res = GSS_S_UNSEQ_TOKEN; 811 goto out; 812 } 813 814 for (i = 0; i < mo->km_length; i++) { 815 if (mo->km_elem[i] == seq) { 816 res = GSS_S_DUPLICATE_TOKEN; 817 goto out; 818 } 819 if (mo->km_elem[i] < seq) { 820 /* 821 * We need to insert this seq here, 822 */ 823 krb5_insert_seq(mo, seq, i); 824 if (check_replay && !check_sequence) 825 res = GSS_S_COMPLETE; 826 else 827 res = GSS_S_UNSEQ_TOKEN; 828 goto out; 829 } 830 } 831 832 out: 833 mtx_unlock(&kc->kc_lock); 834 835 return (res); 836 } 837 838 static uint8_t sgn_alg_des_md5[] = { 0x00, 0x00 }; 839 static uint8_t seal_alg_des[] = { 0x00, 0x00 }; 840 static uint8_t sgn_alg_des3_sha1[] = { 0x04, 0x00 }; 841 static uint8_t seal_alg_des3[] = { 0x02, 0x00 }; 842 static uint8_t seal_alg_rc4[] = { 0x10, 0x00 }; 843 static uint8_t sgn_alg_hmac_md5[] = { 0x11, 0x00 }; 844 845 /* 846 * Return the size of the inner token given the use of the key's 847 * encryption class. For wrap tokens, the length of the padded 848 * plaintext will be added to this. 849 */ 850 static size_t 851 token_length(struct krb5_key_state *key) 852 { 853 854 return (16 + key->ks_class->ec_checksumlen); 855 } 856 857 static OM_uint32 858 krb5_get_mic_old(struct krb5_context *kc, struct mbuf *m, 859 struct mbuf **micp, uint8_t sgn_alg[2]) 860 { 861 struct mbuf *mlast, *mic, *tm; 862 uint8_t *p, dir; 863 size_t tlen, mlen, cklen; 864 uint32_t seq; 865 char buf[8]; 866 867 mlen = m_length(m, &mlast); 868 869 tlen = token_length(kc->kc_tokenkey); 870 p = krb5_make_token("\x01\x01", tlen, tlen, &mic); 871 p += 2; /* TOK_ID */ 872 *p++ = sgn_alg[0]; /* SGN_ALG */ 873 *p++ = sgn_alg[1]; 874 875 *p++ = 0xff; /* filler */ 876 *p++ = 0xff; 877 *p++ = 0xff; 878 *p++ = 0xff; 879 880 /* 881 * SGN_CKSUM: 882 * 883 * Calculate the keyed checksum of the token header plus the 884 * message. 885 */ 886 cklen = kc->kc_checksumkey->ks_class->ec_checksumlen; 887 888 mic->m_len = p - (uint8_t *) mic->m_data; 889 mic->m_next = m; 890 MGET(tm, M_WAITOK, MT_DATA); 891 tm->m_len = cklen; 892 mlast->m_next = tm; 893 894 krb5_checksum(kc->kc_checksumkey, 15, mic, mic->m_len - 8, 895 8 + mlen, cklen); 896 bcopy(tm->m_data, p + 8, cklen); 897 mic->m_next = NULL; 898 mlast->m_next = NULL; 899 m_free(tm); 900 901 /* 902 * SND_SEQ: 903 * 904 * Take the four bytes of the sequence number least 905 * significant first followed by four bytes of direction 906 * marker (zero for initiator and 0xff for acceptor). Encrypt 907 * that data using the SGN_CKSUM as IV. Note: ARC4 wants the 908 * sequence number big-endian. 909 */ 910 seq = atomic_fetchadd_32(&kc->kc_local_seqnumber, 1); 911 if (sgn_alg[0] == 0x11) { 912 p[0] = (seq >> 24); 913 p[1] = (seq >> 16); 914 p[2] = (seq >> 8); 915 p[3] = (seq >> 0); 916 } else { 917 p[0] = (seq >> 0); 918 p[1] = (seq >> 8); 919 p[2] = (seq >> 16); 920 p[3] = (seq >> 24); 921 } 922 if (is_initiator(kc)) { 923 dir = 0; 924 } else { 925 dir = 0xff; 926 } 927 p[4] = dir; 928 p[5] = dir; 929 p[6] = dir; 930 p[7] = dir; 931 bcopy(p + 8, buf, 8); 932 933 /* 934 * Set the mic buffer to its final size so that the encrypt 935 * can see the SND_SEQ part. 936 */ 937 mic->m_len += 8 + cklen; 938 krb5_encrypt(kc->kc_tokenkey, mic, mic->m_len - cklen - 8, 8, buf, 8); 939 940 *micp = mic; 941 return (GSS_S_COMPLETE); 942 } 943 944 static OM_uint32 945 krb5_get_mic_new(struct krb5_context *kc, struct mbuf *m, 946 struct mbuf **micp) 947 { 948 struct krb5_key_state *key = kc->kc_send_sign_Kc; 949 struct mbuf *mlast, *mic; 950 uint8_t *p; 951 int flags; 952 size_t mlen, cklen; 953 uint32_t seq; 954 955 mlen = m_length(m, &mlast); 956 cklen = key->ks_class->ec_checksumlen; 957 958 KASSERT(16 + cklen <= MLEN, ("checksum too large for an mbuf")); 959 MGET(mic, M_WAITOK, MT_DATA); 960 M_ALIGN(mic, 16 + cklen); 961 mic->m_len = 16 + cklen; 962 p = mic->m_data; 963 964 /* TOK_ID */ 965 p[0] = 0x04; 966 p[1] = 0x04; 967 968 /* Flags */ 969 flags = 0; 970 if (is_acceptor(kc)) 971 flags |= GSS_TOKEN_SENT_BY_ACCEPTOR; 972 if (kc->kc_more_flags & ACCEPTOR_SUBKEY) 973 flags |= GSS_TOKEN_ACCEPTOR_SUBKEY; 974 p[2] = flags; 975 976 /* Filler */ 977 p[3] = 0xff; 978 p[4] = 0xff; 979 p[5] = 0xff; 980 p[6] = 0xff; 981 p[7] = 0xff; 982 983 /* SND_SEQ */ 984 p[8] = 0; 985 p[9] = 0; 986 p[10] = 0; 987 p[11] = 0; 988 seq = atomic_fetchadd_32(&kc->kc_local_seqnumber, 1); 989 p[12] = (seq >> 24); 990 p[13] = (seq >> 16); 991 p[14] = (seq >> 8); 992 p[15] = (seq >> 0); 993 994 /* 995 * SGN_CKSUM: 996 * 997 * Calculate the keyed checksum of the message plus the first 998 * 16 bytes of the token header. 999 */ 1000 mlast->m_next = mic; 1001 krb5_checksum(key, 0, m, 0, mlen + 16, cklen); 1002 mlast->m_next = NULL; 1003 1004 *micp = mic; 1005 return (GSS_S_COMPLETE); 1006 } 1007 1008 static OM_uint32 1009 krb5_get_mic(gss_ctx_id_t ctx, OM_uint32 *minor_status, 1010 gss_qop_t qop_req, struct mbuf *m, struct mbuf **micp) 1011 { 1012 struct krb5_context *kc = (struct krb5_context *)ctx; 1013 1014 *minor_status = 0; 1015 1016 if (qop_req != GSS_C_QOP_DEFAULT) 1017 return (GSS_S_BAD_QOP); 1018 1019 if (time_uptime > kc->kc_lifetime) 1020 return (GSS_S_CONTEXT_EXPIRED); 1021 1022 switch (kc->kc_tokenkey->ks_class->ec_type) { 1023 case ETYPE_DES_CBC_CRC: 1024 return (krb5_get_mic_old(kc, m, micp, sgn_alg_des_md5)); 1025 1026 case ETYPE_DES3_CBC_SHA1: 1027 return (krb5_get_mic_old(kc, m, micp, sgn_alg_des3_sha1)); 1028 1029 case ETYPE_ARCFOUR_HMAC_MD5: 1030 case ETYPE_ARCFOUR_HMAC_MD5_56: 1031 return (krb5_get_mic_old(kc, m, micp, sgn_alg_hmac_md5)); 1032 1033 default: 1034 return (krb5_get_mic_new(kc, m, micp)); 1035 } 1036 1037 return (GSS_S_FAILURE); 1038 } 1039 1040 static OM_uint32 1041 krb5_verify_mic_old(struct krb5_context *kc, struct mbuf *m, struct mbuf *mic, 1042 uint8_t sgn_alg[2]) 1043 { 1044 struct mbuf *mlast, *tm; 1045 uint8_t *p, *tp, dir; 1046 size_t mlen, tlen, elen; 1047 size_t cklen; 1048 uint32_t seq; 1049 1050 mlen = m_length(m, &mlast); 1051 1052 tlen = token_length(kc->kc_tokenkey); 1053 p = krb5_verify_token("\x01\x01", tlen, &mic, &elen, FALSE); 1054 if (!p) 1055 return (GSS_S_DEFECTIVE_TOKEN); 1056 #if 0 1057 /* 1058 * Disable this check - heimdal-1.1 generates DES3 MIC tokens 1059 * that are 2 bytes too big. 1060 */ 1061 if (elen != tlen) 1062 return (GSS_S_DEFECTIVE_TOKEN); 1063 #endif 1064 /* TOK_ID */ 1065 p += 2; 1066 1067 /* SGN_ALG */ 1068 if (p[0] != sgn_alg[0] || p[1] != sgn_alg[1]) 1069 return (GSS_S_DEFECTIVE_TOKEN); 1070 p += 2; 1071 1072 if (p[0] != 0xff || p[1] != 0xff || p[2] != 0xff || p[3] != 0xff) 1073 return (GSS_S_DEFECTIVE_TOKEN); 1074 p += 4; 1075 1076 /* 1077 * SGN_CKSUM: 1078 * 1079 * Calculate the keyed checksum of the token header plus the 1080 * message. 1081 */ 1082 cklen = kc->kc_checksumkey->ks_class->ec_checksumlen; 1083 mic->m_len = p - (uint8_t *) mic->m_data; 1084 mic->m_next = m; 1085 MGET(tm, M_WAITOK, MT_DATA); 1086 tm->m_len = cklen; 1087 mlast->m_next = tm; 1088 1089 krb5_checksum(kc->kc_checksumkey, 15, mic, mic->m_len - 8, 1090 8 + mlen, cklen); 1091 mic->m_next = NULL; 1092 mlast->m_next = NULL; 1093 if (bcmp(tm->m_data, p + 8, cklen)) { 1094 m_free(tm); 1095 return (GSS_S_BAD_SIG); 1096 } 1097 1098 /* 1099 * SND_SEQ: 1100 * 1101 * Take the four bytes of the sequence number least 1102 * significant first followed by four bytes of direction 1103 * marker (zero for initiator and 0xff for acceptor). Encrypt 1104 * that data using the SGN_CKSUM as IV. Note: ARC4 wants the 1105 * sequence number big-endian. 1106 */ 1107 bcopy(p, tm->m_data, 8); 1108 tm->m_len = 8; 1109 krb5_decrypt(kc->kc_tokenkey, tm, 0, 8, p + 8, 8); 1110 1111 tp = tm->m_data; 1112 if (sgn_alg[0] == 0x11) { 1113 seq = tp[3] | (tp[2] << 8) | (tp[1] << 16) | (tp[0] << 24); 1114 } else { 1115 seq = tp[0] | (tp[1] << 8) | (tp[2] << 16) | (tp[3] << 24); 1116 } 1117 1118 if (is_initiator(kc)) { 1119 dir = 0xff; 1120 } else { 1121 dir = 0; 1122 } 1123 if (tp[4] != dir || tp[5] != dir || tp[6] != dir || tp[7] != dir) { 1124 m_free(tm); 1125 return (GSS_S_DEFECTIVE_TOKEN); 1126 } 1127 m_free(tm); 1128 1129 if (kc->kc_msg_order.km_flags & 1130 (GSS_C_REPLAY_FLAG | GSS_C_SEQUENCE_FLAG)) { 1131 return (krb5_sequence_check(kc, seq)); 1132 } 1133 1134 return (GSS_S_COMPLETE); 1135 } 1136 1137 static OM_uint32 1138 krb5_verify_mic_new(struct krb5_context *kc, struct mbuf *m, struct mbuf *mic) 1139 { 1140 OM_uint32 res; 1141 struct krb5_key_state *key = kc->kc_recv_sign_Kc; 1142 struct mbuf *mlast; 1143 uint8_t *p; 1144 int flags; 1145 size_t mlen, cklen; 1146 char buf[32]; 1147 1148 mlen = m_length(m, &mlast); 1149 cklen = key->ks_class->ec_checksumlen; 1150 1151 KASSERT(mic->m_next == NULL, ("MIC should be contiguous")); 1152 if (mic->m_len != 16 + cklen) 1153 return (GSS_S_DEFECTIVE_TOKEN); 1154 p = mic->m_data; 1155 1156 /* TOK_ID */ 1157 if (p[0] != 0x04) 1158 return (GSS_S_DEFECTIVE_TOKEN); 1159 if (p[1] != 0x04) 1160 return (GSS_S_DEFECTIVE_TOKEN); 1161 1162 /* Flags */ 1163 flags = 0; 1164 if (is_initiator(kc)) 1165 flags |= GSS_TOKEN_SENT_BY_ACCEPTOR; 1166 if (kc->kc_more_flags & ACCEPTOR_SUBKEY) 1167 flags |= GSS_TOKEN_ACCEPTOR_SUBKEY; 1168 if (p[2] != flags) 1169 return (GSS_S_DEFECTIVE_TOKEN); 1170 1171 /* Filler */ 1172 if (p[3] != 0xff) 1173 return (GSS_S_DEFECTIVE_TOKEN); 1174 if (p[4] != 0xff) 1175 return (GSS_S_DEFECTIVE_TOKEN); 1176 if (p[5] != 0xff) 1177 return (GSS_S_DEFECTIVE_TOKEN); 1178 if (p[6] != 0xff) 1179 return (GSS_S_DEFECTIVE_TOKEN); 1180 if (p[7] != 0xff) 1181 return (GSS_S_DEFECTIVE_TOKEN); 1182 1183 /* SND_SEQ */ 1184 if (kc->kc_msg_order.km_flags & 1185 (GSS_C_REPLAY_FLAG | GSS_C_SEQUENCE_FLAG)) { 1186 uint32_t seq; 1187 if (p[8] || p[9] || p[10] || p[11]) { 1188 res = GSS_S_UNSEQ_TOKEN; 1189 } else { 1190 seq = (p[12] << 24) | (p[13] << 16) 1191 | (p[14] << 8) | p[15]; 1192 res = krb5_sequence_check(kc, seq); 1193 } 1194 if (GSS_ERROR(res)) 1195 return (res); 1196 } else { 1197 res = GSS_S_COMPLETE; 1198 } 1199 1200 /* 1201 * SGN_CKSUM: 1202 * 1203 * Calculate the keyed checksum of the message plus the first 1204 * 16 bytes of the token header. 1205 */ 1206 m_copydata(mic, 16, cklen, buf); 1207 mlast->m_next = mic; 1208 krb5_checksum(key, 0, m, 0, mlen + 16, cklen); 1209 mlast->m_next = NULL; 1210 if (bcmp(buf, p + 16, cklen)) { 1211 return (GSS_S_BAD_SIG); 1212 } 1213 1214 return (GSS_S_COMPLETE); 1215 } 1216 1217 static OM_uint32 1218 krb5_verify_mic(gss_ctx_id_t ctx, OM_uint32 *minor_status, 1219 struct mbuf *m, struct mbuf *mic, gss_qop_t *qop_state) 1220 { 1221 struct krb5_context *kc = (struct krb5_context *)ctx; 1222 1223 *minor_status = 0; 1224 if (qop_state) 1225 *qop_state = GSS_C_QOP_DEFAULT; 1226 1227 if (time_uptime > kc->kc_lifetime) 1228 return (GSS_S_CONTEXT_EXPIRED); 1229 1230 switch (kc->kc_tokenkey->ks_class->ec_type) { 1231 case ETYPE_DES_CBC_CRC: 1232 return (krb5_verify_mic_old(kc, m, mic, sgn_alg_des_md5)); 1233 1234 case ETYPE_ARCFOUR_HMAC_MD5: 1235 case ETYPE_ARCFOUR_HMAC_MD5_56: 1236 return (krb5_verify_mic_old(kc, m, mic, sgn_alg_hmac_md5)); 1237 1238 case ETYPE_DES3_CBC_SHA1: 1239 return (krb5_verify_mic_old(kc, m, mic, sgn_alg_des3_sha1)); 1240 1241 default: 1242 return (krb5_verify_mic_new(kc, m, mic)); 1243 } 1244 1245 return (GSS_S_FAILURE); 1246 } 1247 1248 static OM_uint32 1249 krb5_wrap_old(struct krb5_context *kc, int conf_req_flag, 1250 struct mbuf **mp, int *conf_state, 1251 uint8_t sgn_alg[2], uint8_t seal_alg[2]) 1252 { 1253 struct mbuf *m, *mlast, *tm, *cm, *pm; 1254 size_t mlen, tlen, padlen, datalen; 1255 uint8_t *p, dir; 1256 size_t cklen; 1257 uint8_t buf[8]; 1258 uint32_t seq; 1259 1260 /* 1261 * How many trailing pad bytes do we need? 1262 */ 1263 m = *mp; 1264 mlen = m_length(m, &mlast); 1265 tlen = kc->kc_tokenkey->ks_class->ec_msgblocklen; 1266 padlen = tlen - (mlen % tlen); 1267 1268 /* 1269 * The data part of the token has eight bytes of random 1270 * confounder prepended and followed by up to eight bytes of 1271 * padding bytes each of which is set to the number of padding 1272 * bytes. 1273 */ 1274 datalen = mlen + 8 + padlen; 1275 tlen = token_length(kc->kc_tokenkey); 1276 1277 p = krb5_make_token("\x02\x01", tlen, datalen + tlen, &tm); 1278 p += 2; /* TOK_ID */ 1279 *p++ = sgn_alg[0]; /* SGN_ALG */ 1280 *p++ = sgn_alg[1]; 1281 if (conf_req_flag) { 1282 *p++ = seal_alg[0]; /* SEAL_ALG */ 1283 *p++ = seal_alg[1]; 1284 } else { 1285 *p++ = 0xff; /* SEAL_ALG = none */ 1286 *p++ = 0xff; 1287 } 1288 1289 *p++ = 0xff; /* filler */ 1290 *p++ = 0xff; 1291 1292 /* 1293 * Copy the padded message data. 1294 */ 1295 if (M_LEADINGSPACE(m) >= 8) { 1296 m->m_data -= 8; 1297 m->m_len += 8; 1298 } else { 1299 MGET(cm, M_WAITOK, MT_DATA); 1300 cm->m_len = 8; 1301 cm->m_next = m; 1302 m = cm; 1303 } 1304 arc4rand(m->m_data, 8, 0); 1305 if (M_TRAILINGSPACE(mlast) >= padlen) { 1306 memset(mlast->m_data + mlast->m_len, padlen, padlen); 1307 mlast->m_len += padlen; 1308 } else { 1309 MGET(pm, M_WAITOK, MT_DATA); 1310 memset(pm->m_data, padlen, padlen); 1311 pm->m_len = padlen; 1312 mlast->m_next = pm; 1313 mlast = pm; 1314 } 1315 tm->m_next = m; 1316 1317 /* 1318 * SGN_CKSUM: 1319 * 1320 * Calculate the keyed checksum of the token header plus the 1321 * padded message. Fiddle with tm->m_len so that we only 1322 * checksum the 8 bytes of head that we care about. 1323 */ 1324 cklen = kc->kc_checksumkey->ks_class->ec_checksumlen; 1325 tlen = tm->m_len; 1326 tm->m_len = p - (uint8_t *) tm->m_data; 1327 MGET(cm, M_WAITOK, MT_DATA); 1328 cm->m_len = cklen; 1329 mlast->m_next = cm; 1330 krb5_checksum(kc->kc_checksumkey, 13, tm, tm->m_len - 8, 1331 datalen + 8, cklen); 1332 tm->m_len = tlen; 1333 mlast->m_next = NULL; 1334 bcopy(cm->m_data, p + 8, cklen); 1335 m_free(cm); 1336 1337 /* 1338 * SND_SEQ: 1339 * 1340 * Take the four bytes of the sequence number least 1341 * significant first (most significant first for ARCFOUR) 1342 * followed by four bytes of direction marker (zero for 1343 * initiator and 0xff for acceptor). Encrypt that data using 1344 * the SGN_CKSUM as IV. 1345 */ 1346 seq = atomic_fetchadd_32(&kc->kc_local_seqnumber, 1); 1347 if (sgn_alg[0] == 0x11) { 1348 p[0] = (seq >> 24); 1349 p[1] = (seq >> 16); 1350 p[2] = (seq >> 8); 1351 p[3] = (seq >> 0); 1352 } else { 1353 p[0] = (seq >> 0); 1354 p[1] = (seq >> 8); 1355 p[2] = (seq >> 16); 1356 p[3] = (seq >> 24); 1357 } 1358 if (is_initiator(kc)) { 1359 dir = 0; 1360 } else { 1361 dir = 0xff; 1362 } 1363 p[4] = dir; 1364 p[5] = dir; 1365 p[6] = dir; 1366 p[7] = dir; 1367 krb5_encrypt(kc->kc_tokenkey, tm, p - (uint8_t *) tm->m_data, 1368 8, p + 8, 8); 1369 1370 if (conf_req_flag) { 1371 /* 1372 * Encrypt the padded message with an IV of zero for 1373 * DES and DES3, or an IV of the sequence number in 1374 * big-endian format for ARCFOUR. 1375 */ 1376 if (seal_alg[0] == 0x10) { 1377 buf[0] = (seq >> 24); 1378 buf[1] = (seq >> 16); 1379 buf[2] = (seq >> 8); 1380 buf[3] = (seq >> 0); 1381 krb5_encrypt(kc->kc_encryptkey, m, 0, datalen, 1382 buf, 4); 1383 } else { 1384 krb5_encrypt(kc->kc_encryptkey, m, 0, datalen, 1385 NULL, 0); 1386 } 1387 } 1388 1389 if (conf_state) 1390 *conf_state = conf_req_flag; 1391 1392 *mp = tm; 1393 return (GSS_S_COMPLETE); 1394 } 1395 1396 static OM_uint32 1397 krb5_wrap_new(struct krb5_context *kc, int conf_req_flag, 1398 struct mbuf **mp, int *conf_state) 1399 { 1400 struct krb5_key_state *Ke = kc->kc_send_seal_Ke; 1401 struct krb5_key_state *Ki = kc->kc_send_seal_Ki; 1402 struct krb5_key_state *Kc = kc->kc_send_seal_Kc; 1403 const struct krb5_encryption_class *ec = Ke->ks_class; 1404 struct mbuf *m, *mlast, *tm; 1405 uint8_t *p; 1406 int flags, EC; 1407 size_t mlen, blen, mblen, cklen, ctlen; 1408 uint32_t seq; 1409 static char zpad[32]; 1410 1411 m = *mp; 1412 mlen = m_length(m, &mlast); 1413 1414 blen = ec->ec_blocklen; 1415 mblen = ec->ec_msgblocklen; 1416 cklen = ec->ec_checksumlen; 1417 1418 if (conf_req_flag) { 1419 /* 1420 * For sealed messages, we need space for 16 bytes of 1421 * header, blen confounder, plaintext, padding, copy 1422 * of header and checksum. 1423 * 1424 * We pad to mblen (which may be different from 1425 * blen). If the encryption class is using CTS, mblen 1426 * will be one (i.e. no padding required). 1427 */ 1428 if (mblen > 1) 1429 EC = mlen % mblen; 1430 else 1431 EC = 0; 1432 ctlen = blen + mlen + EC + 16; 1433 1434 /* 1435 * Put initial header and confounder before the 1436 * message. 1437 */ 1438 M_PREPEND(m, 16 + blen, M_WAITOK); 1439 1440 /* 1441 * Append padding + copy of header and checksum. Try 1442 * to fit this into the end of the original message, 1443 * otherwise allocate a trailer. 1444 */ 1445 if (M_TRAILINGSPACE(mlast) >= EC + 16 + cklen) { 1446 tm = NULL; 1447 mlast->m_len += EC + 16 + cklen; 1448 } else { 1449 MGET(tm, M_WAITOK, MT_DATA); 1450 tm->m_len = EC + 16 + cklen; 1451 mlast->m_next = tm; 1452 } 1453 } else { 1454 /* 1455 * For unsealed messages, we need 16 bytes of header 1456 * plus space for the plaintext and a checksum. EC is 1457 * set to the checksum size. We leave space in tm for 1458 * a copy of the header - this will be trimmed later. 1459 */ 1460 M_PREPEND(m, 16, M_WAITOK); 1461 1462 MGET(tm, M_WAITOK, MT_DATA); 1463 tm->m_len = cklen + 16; 1464 mlast->m_next = tm; 1465 ctlen = 0; 1466 EC = cklen; 1467 } 1468 1469 p = m->m_data; 1470 1471 /* TOK_ID */ 1472 p[0] = 0x05; 1473 p[1] = 0x04; 1474 1475 /* Flags */ 1476 flags = 0; 1477 if (conf_req_flag) 1478 flags = GSS_TOKEN_SEALED; 1479 if (is_acceptor(kc)) 1480 flags |= GSS_TOKEN_SENT_BY_ACCEPTOR; 1481 if (kc->kc_more_flags & ACCEPTOR_SUBKEY) 1482 flags |= GSS_TOKEN_ACCEPTOR_SUBKEY; 1483 p[2] = flags; 1484 1485 /* Filler */ 1486 p[3] = 0xff; 1487 1488 /* EC + RRC - set to zero initially */ 1489 p[4] = 0; 1490 p[5] = 0; 1491 p[6] = 0; 1492 p[7] = 0; 1493 1494 /* SND_SEQ */ 1495 p[8] = 0; 1496 p[9] = 0; 1497 p[10] = 0; 1498 p[11] = 0; 1499 seq = atomic_fetchadd_32(&kc->kc_local_seqnumber, 1); 1500 p[12] = (seq >> 24); 1501 p[13] = (seq >> 16); 1502 p[14] = (seq >> 8); 1503 p[15] = (seq >> 0); 1504 1505 if (conf_req_flag) { 1506 /* 1507 * Encrypt according to RFC 4121 section 4.2 and RFC 1508 * 3961 section 5.3. Note: we don't generate tokens 1509 * with RRC values other than zero. If we did, we 1510 * should zero RRC in the copied header. 1511 */ 1512 arc4rand(p + 16, blen, 0); 1513 if (EC) { 1514 m_copyback(m, 16 + blen + mlen, EC, zpad); 1515 } 1516 m_copyback(m, 16 + blen + mlen + EC, 16, p); 1517 1518 krb5_checksum(Ki, 0, m, 16, ctlen, cklen); 1519 krb5_encrypt(Ke, m, 16, ctlen, NULL, 0); 1520 } else { 1521 /* 1522 * The plaintext message is followed by a checksum of 1523 * the plaintext plus a version of the header where EC 1524 * and RRC are set to zero. Also, the original EC must 1525 * be our checksum size. 1526 */ 1527 bcopy(p, tm->m_data, 16); 1528 krb5_checksum(Kc, 0, m, 16, mlen + 16, cklen); 1529 tm->m_data += 16; 1530 tm->m_len -= 16; 1531 } 1532 1533 /* 1534 * Finally set EC to its actual value 1535 */ 1536 p[4] = EC >> 8; 1537 p[5] = EC; 1538 1539 *mp = m; 1540 return (GSS_S_COMPLETE); 1541 } 1542 1543 static OM_uint32 1544 krb5_wrap(gss_ctx_id_t ctx, OM_uint32 *minor_status, 1545 int conf_req_flag, gss_qop_t qop_req, 1546 struct mbuf **mp, int *conf_state) 1547 { 1548 struct krb5_context *kc = (struct krb5_context *)ctx; 1549 1550 *minor_status = 0; 1551 if (conf_state) 1552 *conf_state = 0; 1553 1554 if (qop_req != GSS_C_QOP_DEFAULT) 1555 return (GSS_S_BAD_QOP); 1556 1557 if (time_uptime > kc->kc_lifetime) 1558 return (GSS_S_CONTEXT_EXPIRED); 1559 1560 switch (kc->kc_tokenkey->ks_class->ec_type) { 1561 case ETYPE_DES_CBC_CRC: 1562 return (krb5_wrap_old(kc, conf_req_flag, 1563 mp, conf_state, sgn_alg_des_md5, seal_alg_des)); 1564 1565 case ETYPE_ARCFOUR_HMAC_MD5: 1566 case ETYPE_ARCFOUR_HMAC_MD5_56: 1567 return (krb5_wrap_old(kc, conf_req_flag, 1568 mp, conf_state, sgn_alg_hmac_md5, seal_alg_rc4)); 1569 1570 case ETYPE_DES3_CBC_SHA1: 1571 return (krb5_wrap_old(kc, conf_req_flag, 1572 mp, conf_state, sgn_alg_des3_sha1, seal_alg_des3)); 1573 1574 default: 1575 return (krb5_wrap_new(kc, conf_req_flag, mp, conf_state)); 1576 } 1577 1578 return (GSS_S_FAILURE); 1579 } 1580 1581 static void 1582 m_trim(struct mbuf *m, int len) 1583 { 1584 struct mbuf *n; 1585 int off; 1586 1587 if (m == NULL) 1588 return; 1589 n = m_getptr(m, len, &off); 1590 if (n) { 1591 n->m_len = off; 1592 if (n->m_next) { 1593 m_freem(n->m_next); 1594 n->m_next = NULL; 1595 } 1596 } 1597 } 1598 1599 static OM_uint32 1600 krb5_unwrap_old(struct krb5_context *kc, struct mbuf **mp, int *conf_state, 1601 uint8_t sgn_alg[2], uint8_t seal_alg[2]) 1602 { 1603 OM_uint32 res; 1604 struct mbuf *m, *mlast, *hm, *cm, *n; 1605 uint8_t *p, dir; 1606 size_t tlen, elen, datalen, padlen; 1607 size_t cklen; 1608 uint8_t buf[32]; 1609 uint32_t seq; 1610 int i, conf; 1611 1612 m = *mp; 1613 m_length(m, &mlast); 1614 1615 tlen = token_length(kc->kc_tokenkey); 1616 cklen = kc->kc_tokenkey->ks_class->ec_checksumlen; 1617 1618 p = krb5_verify_token("\x02\x01", tlen, &m, &elen, TRUE); 1619 *mp = m; 1620 if (!p) 1621 return (GSS_S_DEFECTIVE_TOKEN); 1622 datalen = elen - tlen; 1623 1624 /* 1625 * Trim the framing header first to make life a little easier 1626 * later. 1627 */ 1628 m_adj(m, p - (uint8_t *) m->m_data); 1629 1630 /* TOK_ID */ 1631 p += 2; 1632 1633 /* SGN_ALG */ 1634 if (p[0] != sgn_alg[0] || p[1] != sgn_alg[1]) 1635 return (GSS_S_DEFECTIVE_TOKEN); 1636 p += 2; 1637 1638 /* SEAL_ALG */ 1639 if (p[0] == seal_alg[0] && p[1] == seal_alg[1]) 1640 conf = 1; 1641 else if (p[0] == 0xff && p[1] == 0xff) 1642 conf = 0; 1643 else 1644 return (GSS_S_DEFECTIVE_TOKEN); 1645 p += 2; 1646 1647 if (p[0] != 0xff || p[1] != 0xff) 1648 return (GSS_S_DEFECTIVE_TOKEN); 1649 p += 2; 1650 1651 /* 1652 * SND_SEQ: 1653 * 1654 * Take the four bytes of the sequence number least 1655 * significant first (most significant for ARCFOUR) followed 1656 * by four bytes of direction marker (zero for initiator and 1657 * 0xff for acceptor). Encrypt that data using the SGN_CKSUM 1658 * as IV. 1659 */ 1660 krb5_decrypt(kc->kc_tokenkey, m, 8, 8, p + 8, 8); 1661 if (sgn_alg[0] == 0x11) { 1662 seq = p[3] | (p[2] << 8) | (p[1] << 16) | (p[0] << 24); 1663 } else { 1664 seq = p[0] | (p[1] << 8) | (p[2] << 16) | (p[3] << 24); 1665 } 1666 1667 if (is_initiator(kc)) { 1668 dir = 0xff; 1669 } else { 1670 dir = 0; 1671 } 1672 if (p[4] != dir || p[5] != dir || p[6] != dir || p[7] != dir) 1673 return (GSS_S_DEFECTIVE_TOKEN); 1674 1675 if (kc->kc_msg_order.km_flags & 1676 (GSS_C_REPLAY_FLAG | GSS_C_SEQUENCE_FLAG)) { 1677 res = krb5_sequence_check(kc, seq); 1678 if (GSS_ERROR(res)) 1679 return (res); 1680 } else { 1681 res = GSS_S_COMPLETE; 1682 } 1683 1684 /* 1685 * If the token was encrypted, decode it in-place. 1686 */ 1687 if (conf) { 1688 /* 1689 * Decrypt the padded message with an IV of zero for 1690 * DES and DES3 or an IV of the big-endian encoded 1691 * sequence number for ARCFOUR. 1692 */ 1693 if (seal_alg[0] == 0x10) { 1694 krb5_decrypt(kc->kc_encryptkey, m, 16 + cklen, 1695 datalen, p, 4); 1696 } else { 1697 krb5_decrypt(kc->kc_encryptkey, m, 16 + cklen, 1698 datalen, NULL, 0); 1699 } 1700 } 1701 if (conf_state) 1702 *conf_state = conf; 1703 1704 /* 1705 * Check the trailing pad bytes. 1706 * RFC1964 specifies between 1<->8 bytes, each with a binary value 1707 * equal to the number of bytes. 1708 */ 1709 if (mlast->m_len > 0) 1710 padlen = mlast->m_data[mlast->m_len - 1]; 1711 else { 1712 n = m_getptr(m, tlen + datalen - 1, &i); 1713 /* 1714 * When the position is exactly equal to the # of data bytes 1715 * in the mbuf list, m_getptr() will return the last mbuf in 1716 * the list and an off == m_len for that mbuf, so that case 1717 * needs to be checked as well as a NULL return. 1718 */ 1719 if (n == NULL || n->m_len == i) 1720 return (GSS_S_DEFECTIVE_TOKEN); 1721 padlen = n->m_data[i]; 1722 } 1723 if (padlen < 1 || padlen > 8 || padlen > tlen + datalen) 1724 return (GSS_S_DEFECTIVE_TOKEN); 1725 m_copydata(m, tlen + datalen - padlen, padlen, buf); 1726 for (i = 0; i < padlen; i++) { 1727 if (buf[i] != padlen) { 1728 return (GSS_S_DEFECTIVE_TOKEN); 1729 } 1730 } 1731 1732 /* 1733 * SGN_CKSUM: 1734 * 1735 * Calculate the keyed checksum of the token header plus the 1736 * padded message. We do a little mbuf surgery to trim out the 1737 * parts we don't want to checksum. 1738 */ 1739 hm = m; 1740 *mp = m = m_split(m, 16 + cklen, M_WAITOK); 1741 mlast = m_last(m); 1742 hm->m_len = 8; 1743 hm->m_next = m; 1744 MGET(cm, M_WAITOK, MT_DATA); 1745 cm->m_len = cklen; 1746 mlast->m_next = cm; 1747 1748 krb5_checksum(kc->kc_checksumkey, 13, hm, 0, datalen + 8, cklen); 1749 hm->m_next = NULL; 1750 mlast->m_next = NULL; 1751 1752 if (bcmp(cm->m_data, hm->m_data + 16, cklen)) { 1753 m_freem(hm); 1754 m_free(cm); 1755 return (GSS_S_BAD_SIG); 1756 } 1757 m_freem(hm); 1758 m_free(cm); 1759 1760 /* 1761 * Trim off the confounder and padding. 1762 */ 1763 m_adj(m, 8); 1764 if (mlast->m_len >= padlen) { 1765 mlast->m_len -= padlen; 1766 } else { 1767 m_trim(m, datalen - 8 - padlen); 1768 } 1769 1770 *mp = m; 1771 return (res); 1772 } 1773 1774 static OM_uint32 1775 krb5_unwrap_new(struct krb5_context *kc, struct mbuf **mp, int *conf_state) 1776 { 1777 OM_uint32 res; 1778 struct krb5_key_state *Ke = kc->kc_recv_seal_Ke; 1779 struct krb5_key_state *Ki = kc->kc_recv_seal_Ki; 1780 struct krb5_key_state *Kc = kc->kc_recv_seal_Kc; 1781 const struct krb5_encryption_class *ec = Ke->ks_class; 1782 struct mbuf *m, *mlast, *hm, *cm; 1783 uint8_t *p; 1784 int sealed, flags, EC, RRC; 1785 size_t blen, cklen, ctlen, mlen, plen, tlen; 1786 char buf[32], buf2[32]; 1787 1788 m = *mp; 1789 mlen = m_length(m, &mlast); 1790 1791 if (mlen <= 16) 1792 return (GSS_S_DEFECTIVE_TOKEN); 1793 if (m->m_len < 16) { 1794 m = m_pullup(m, 16); 1795 *mp = m; 1796 } 1797 p = m->m_data; 1798 1799 /* TOK_ID */ 1800 if (p[0] != 0x05) 1801 return (GSS_S_DEFECTIVE_TOKEN); 1802 if (p[1] != 0x04) 1803 return (GSS_S_DEFECTIVE_TOKEN); 1804 1805 /* Flags */ 1806 sealed = p[2] & GSS_TOKEN_SEALED; 1807 flags = sealed; 1808 if (is_initiator(kc)) 1809 flags |= GSS_TOKEN_SENT_BY_ACCEPTOR; 1810 if (kc->kc_more_flags & ACCEPTOR_SUBKEY) 1811 flags |= GSS_TOKEN_ACCEPTOR_SUBKEY; 1812 if (p[2] != flags) 1813 return (GSS_S_DEFECTIVE_TOKEN); 1814 1815 /* Filler */ 1816 if (p[3] != 0xff) 1817 return (GSS_S_DEFECTIVE_TOKEN); 1818 1819 /* EC + RRC */ 1820 EC = (p[4] << 8) + p[5]; 1821 RRC = (p[6] << 8) + p[7]; 1822 1823 /* SND_SEQ */ 1824 if (kc->kc_msg_order.km_flags & 1825 (GSS_C_REPLAY_FLAG | GSS_C_SEQUENCE_FLAG)) { 1826 uint32_t seq; 1827 if (p[8] || p[9] || p[10] || p[11]) { 1828 res = GSS_S_UNSEQ_TOKEN; 1829 } else { 1830 seq = (p[12] << 24) | (p[13] << 16) 1831 | (p[14] << 8) | p[15]; 1832 res = krb5_sequence_check(kc, seq); 1833 } 1834 if (GSS_ERROR(res)) 1835 return (res); 1836 } else { 1837 res = GSS_S_COMPLETE; 1838 } 1839 1840 /* 1841 * Separate the header before dealing with RRC. We only need 1842 * to keep the header if the message isn't encrypted. 1843 */ 1844 if (sealed) { 1845 hm = NULL; 1846 m_adj(m, 16); 1847 } else { 1848 hm = m; 1849 *mp = m = m_split(m, 16, M_WAITOK); 1850 mlast = m_last(m); 1851 } 1852 1853 /* 1854 * Undo the effects of RRC by rotating left. 1855 */ 1856 if (RRC > 0) { 1857 struct mbuf *rm; 1858 size_t rlen; 1859 1860 rlen = mlen - 16; 1861 if (RRC <= sizeof(buf) && m->m_len >= rlen) { 1862 /* 1863 * Simple case, just rearrange the bytes in m. 1864 */ 1865 bcopy(m->m_data, buf, RRC); 1866 bcopy(m->m_data + RRC, m->m_data, rlen - RRC); 1867 bcopy(buf, m->m_data + rlen - RRC, RRC); 1868 } else { 1869 /* 1870 * More complicated - rearrange the mbuf 1871 * chain. 1872 */ 1873 rm = m; 1874 *mp = m = m_split(m, RRC, M_WAITOK); 1875 m_cat(m, rm); 1876 mlast = rm; 1877 } 1878 } 1879 1880 blen = ec->ec_blocklen; 1881 cklen = ec->ec_checksumlen; 1882 if (sealed) { 1883 /* 1884 * Decrypt according to RFC 4121 section 4.2 and RFC 1885 * 3961 section 5.3. The message must be large enough 1886 * for a blocksize confounder, at least one block of 1887 * cyphertext and a checksum. 1888 */ 1889 if (mlen < 16 + 2*blen + cklen) 1890 return (GSS_S_DEFECTIVE_TOKEN); 1891 1892 ctlen = mlen - 16 - cklen; 1893 krb5_decrypt(Ke, m, 0, ctlen, NULL, 0); 1894 1895 /* 1896 * The size of the plaintext is ctlen minus blocklen 1897 * (for the confounder), 16 (for the copy of the token 1898 * header) and EC (for the filler). The actual 1899 * plaintext starts after the confounder. 1900 */ 1901 plen = ctlen - blen - 16 - EC; 1902 1903 /* 1904 * Checksum the padded plaintext. 1905 */ 1906 m_copydata(m, ctlen, cklen, buf); 1907 krb5_checksum(Ki, 0, m, 0, ctlen, cklen); 1908 m_copydata(m, ctlen, cklen, buf2); 1909 1910 if (bcmp(buf, buf2, cklen)) 1911 return (GSS_S_BAD_SIG); 1912 1913 /* 1914 * Trim the message back to just plaintext. 1915 */ 1916 m_adj(m, blen); 1917 tlen = 16 + EC + cklen; 1918 if (mlast->m_len >= tlen) { 1919 mlast->m_len -= tlen; 1920 } else { 1921 m_trim(m, plen); 1922 } 1923 } else { 1924 /* 1925 * The plaintext message is followed by a checksum of 1926 * the plaintext plus a version of the header where EC 1927 * and RRC are set to zero. Also, the original EC must 1928 * be our checksum size. 1929 */ 1930 if (mlen < 16 + cklen || EC != cklen) 1931 return (GSS_S_DEFECTIVE_TOKEN); 1932 1933 /* 1934 * The size of the plaintext is simply the message 1935 * size less header and checksum. The plaintext starts 1936 * right after the header (which we have saved in hm). 1937 */ 1938 plen = mlen - 16 - cklen; 1939 1940 /* 1941 * Insert a copy of the header (with EC and RRC set to 1942 * zero) between the plaintext message and the 1943 * checksum. 1944 */ 1945 p = hm->m_data; 1946 p[4] = p[5] = p[6] = p[7] = 0; 1947 1948 cm = m_split(m, plen, M_WAITOK); 1949 mlast = m_last(m); 1950 m->m_next = hm; 1951 hm->m_next = cm; 1952 1953 bcopy(cm->m_data, buf, cklen); 1954 krb5_checksum(Kc, 0, m, 0, plen + 16, cklen); 1955 if (bcmp(cm->m_data, buf, cklen)) 1956 return (GSS_S_BAD_SIG); 1957 1958 /* 1959 * The checksum matches, discard all buf the plaintext. 1960 */ 1961 mlast->m_next = NULL; 1962 m_freem(hm); 1963 } 1964 1965 if (conf_state) 1966 *conf_state = (sealed != 0); 1967 1968 return (res); 1969 } 1970 1971 static OM_uint32 1972 krb5_unwrap(gss_ctx_id_t ctx, OM_uint32 *minor_status, 1973 struct mbuf **mp, int *conf_state, gss_qop_t *qop_state) 1974 { 1975 struct krb5_context *kc = (struct krb5_context *)ctx; 1976 OM_uint32 maj_stat; 1977 1978 *minor_status = 0; 1979 if (qop_state) 1980 *qop_state = GSS_C_QOP_DEFAULT; 1981 if (conf_state) 1982 *conf_state = 0; 1983 1984 if (time_uptime > kc->kc_lifetime) 1985 return (GSS_S_CONTEXT_EXPIRED); 1986 1987 switch (kc->kc_tokenkey->ks_class->ec_type) { 1988 case ETYPE_DES_CBC_CRC: 1989 maj_stat = krb5_unwrap_old(kc, mp, conf_state, 1990 sgn_alg_des_md5, seal_alg_des); 1991 break; 1992 1993 case ETYPE_ARCFOUR_HMAC_MD5: 1994 case ETYPE_ARCFOUR_HMAC_MD5_56: 1995 maj_stat = krb5_unwrap_old(kc, mp, conf_state, 1996 sgn_alg_hmac_md5, seal_alg_rc4); 1997 break; 1998 1999 case ETYPE_DES3_CBC_SHA1: 2000 maj_stat = krb5_unwrap_old(kc, mp, conf_state, 2001 sgn_alg_des3_sha1, seal_alg_des3); 2002 break; 2003 2004 default: 2005 maj_stat = krb5_unwrap_new(kc, mp, conf_state); 2006 break; 2007 } 2008 2009 if (GSS_ERROR(maj_stat)) { 2010 m_freem(*mp); 2011 *mp = NULL; 2012 } 2013 2014 return (maj_stat); 2015 } 2016 2017 static OM_uint32 2018 krb5_wrap_size_limit(gss_ctx_id_t ctx, OM_uint32 *minor_status, 2019 int conf_req_flag, gss_qop_t qop_req, OM_uint32 req_output_size, 2020 OM_uint32 *max_input_size) 2021 { 2022 struct krb5_context *kc = (struct krb5_context *)ctx; 2023 const struct krb5_encryption_class *ec; 2024 OM_uint32 overhead; 2025 2026 *minor_status = 0; 2027 *max_input_size = 0; 2028 2029 if (qop_req != GSS_C_QOP_DEFAULT) 2030 return (GSS_S_BAD_QOP); 2031 2032 ec = kc->kc_tokenkey->ks_class; 2033 switch (ec->ec_type) { 2034 case ETYPE_DES_CBC_CRC: 2035 case ETYPE_DES3_CBC_SHA1: 2036 case ETYPE_ARCFOUR_HMAC_MD5: 2037 case ETYPE_ARCFOUR_HMAC_MD5_56: 2038 /* 2039 * up to 5 bytes for [APPLICATION 0] SEQUENCE 2040 * 2 + krb5 oid length 2041 * 8 bytes of header 2042 * 8 bytes of confounder 2043 * maximum of 8 bytes of padding 2044 * checksum 2045 */ 2046 overhead = 5 + 2 + krb5_mech_oid.length; 2047 overhead += 8 + 8 + ec->ec_msgblocklen; 2048 overhead += ec->ec_checksumlen; 2049 break; 2050 2051 default: 2052 if (conf_req_flag) { 2053 /* 2054 * 16 byts of header 2055 * blocklen bytes of confounder 2056 * up to msgblocklen - 1 bytes of padding 2057 * 16 bytes for copy of header 2058 * checksum 2059 */ 2060 overhead = 16 + ec->ec_blocklen; 2061 overhead += ec->ec_msgblocklen - 1; 2062 overhead += 16; 2063 overhead += ec->ec_checksumlen; 2064 } else { 2065 /* 2066 * 16 bytes of header plus checksum. 2067 */ 2068 overhead = 16 + ec->ec_checksumlen; 2069 } 2070 } 2071 2072 *max_input_size = req_output_size - overhead; 2073 2074 return (GSS_S_COMPLETE); 2075 } 2076 2077 static kobj_method_t krb5_methods[] = { 2078 KOBJMETHOD(kgss_init, krb5_init), 2079 KOBJMETHOD(kgss_import, krb5_import), 2080 KOBJMETHOD(kgss_delete, krb5_delete), 2081 KOBJMETHOD(kgss_mech_type, krb5_mech_type), 2082 KOBJMETHOD(kgss_get_mic, krb5_get_mic), 2083 KOBJMETHOD(kgss_verify_mic, krb5_verify_mic), 2084 KOBJMETHOD(kgss_wrap, krb5_wrap), 2085 KOBJMETHOD(kgss_unwrap, krb5_unwrap), 2086 KOBJMETHOD(kgss_wrap_size_limit, krb5_wrap_size_limit), 2087 { 0, 0 } 2088 }; 2089 2090 static struct kobj_class krb5_class = { 2091 "kerberosv5", 2092 krb5_methods, 2093 sizeof(struct krb5_context) 2094 }; 2095 2096 /* 2097 * Kernel module glue 2098 */ 2099 static int 2100 kgssapi_krb5_modevent(module_t mod, int type, void *data) 2101 { 2102 2103 switch (type) { 2104 case MOD_LOAD: 2105 kgss_install_mech(&krb5_mech_oid, "kerberosv5", &krb5_class); 2106 break; 2107 2108 case MOD_UNLOAD: 2109 kgss_uninstall_mech(&krb5_mech_oid); 2110 break; 2111 } 2112 2113 return (0); 2114 } 2115 static moduledata_t kgssapi_krb5_mod = { 2116 "kgssapi_krb5", 2117 kgssapi_krb5_modevent, 2118 NULL, 2119 }; 2120 DECLARE_MODULE(kgssapi_krb5, kgssapi_krb5_mod, SI_SUB_VFS, SI_ORDER_ANY); 2121 MODULE_DEPEND(kgssapi_krb5, kgssapi, 1, 1, 1); 2122 MODULE_DEPEND(kgssapi_krb5, crypto, 1, 1, 1); 2123 MODULE_DEPEND(kgssapi_krb5, rc4, 1, 1, 1); 2124 MODULE_VERSION(kgssapi_krb5, 1); 2125