1 /* 2 * Copyright 1999-2024 The OpenSSL Project Authors. All Rights Reserved. 3 * 4 * Licensed under the Apache License 2.0 (the "License"). You may not use 5 * this file except in compliance with the License. You can obtain a copy 6 * in the file LICENSE in the source distribution or at 7 * https://www.openssl.org/source/license.html 8 */ 9 10 /* X509 v3 extension utilities */ 11 12 #include "e_os.h" 13 #include "internal/cryptlib.h" 14 #include <stdio.h> 15 #include <string.h> 16 #include "crypto/ctype.h" 17 #include <openssl/conf.h> 18 #include <openssl/crypto.h> 19 #include <openssl/x509v3.h> 20 #include "crypto/x509.h" 21 #include <openssl/bn.h> 22 #include "ext_dat.h" 23 #include "x509_local.h" 24 25 static char *strip_spaces(char *name); 26 static int sk_strcmp(const char *const *a, const char *const *b); 27 static STACK_OF(OPENSSL_STRING) *get_email(const X509_NAME *name, 28 GENERAL_NAMES *gens); 29 static void str_free(OPENSSL_STRING str); 30 static int append_ia5(STACK_OF(OPENSSL_STRING) **sk, 31 const ASN1_IA5STRING *email); 32 33 static int ipv4_from_asc(unsigned char *v4, const char *in); 34 static int ipv6_from_asc(unsigned char *v6, const char *in); 35 static int ipv6_cb(const char *elem, int len, void *usr); 36 static int ipv6_hex(unsigned char *out, const char *in, int inlen); 37 38 /* Add a CONF_VALUE name value pair to stack */ 39 40 static int x509v3_add_len_value(const char *name, const char *value, 41 size_t vallen, STACK_OF(CONF_VALUE) **extlist) 42 { 43 CONF_VALUE *vtmp = NULL; 44 char *tname = NULL, *tvalue = NULL; 45 int sk_allocated = (*extlist == NULL); 46 47 if (name != NULL && (tname = OPENSSL_strdup(name)) == NULL) 48 goto err; 49 if (value != NULL) { 50 /* We don't allow embeded NUL characters */ 51 if (memchr(value, 0, vallen) != NULL) 52 goto err; 53 tvalue = OPENSSL_strndup(value, vallen); 54 if (tvalue == NULL) 55 goto err; 56 } 57 if ((vtmp = OPENSSL_malloc(sizeof(*vtmp))) == NULL) 58 goto err; 59 if (sk_allocated && (*extlist = sk_CONF_VALUE_new_null()) == NULL) 60 goto err; 61 vtmp->section = NULL; 62 vtmp->name = tname; 63 vtmp->value = tvalue; 64 if (!sk_CONF_VALUE_push(*extlist, vtmp)) 65 goto err; 66 return 1; 67 err: 68 ERR_raise(ERR_LIB_X509V3, ERR_R_MALLOC_FAILURE); 69 if (sk_allocated) { 70 sk_CONF_VALUE_free(*extlist); 71 *extlist = NULL; 72 } 73 OPENSSL_free(vtmp); 74 OPENSSL_free(tname); 75 OPENSSL_free(tvalue); 76 return 0; 77 } 78 79 int X509V3_add_value(const char *name, const char *value, 80 STACK_OF(CONF_VALUE) **extlist) 81 { 82 return x509v3_add_len_value(name, value, 83 value != NULL ? strlen((const char *)value) : 0, 84 extlist); 85 } 86 87 int X509V3_add_value_uchar(const char *name, const unsigned char *value, 88 STACK_OF(CONF_VALUE) **extlist) 89 { 90 return x509v3_add_len_value(name, (const char *)value, 91 value != NULL ? strlen((const char *)value) : 0, 92 extlist); 93 } 94 95 int x509v3_add_len_value_uchar(const char *name, const unsigned char *value, 96 size_t vallen, STACK_OF(CONF_VALUE) **extlist) 97 { 98 return x509v3_add_len_value(name, (const char *)value, vallen, extlist); 99 } 100 101 /* Free function for STACK_OF(CONF_VALUE) */ 102 103 void X509V3_conf_free(CONF_VALUE *conf) 104 { 105 if (!conf) 106 return; 107 OPENSSL_free(conf->name); 108 OPENSSL_free(conf->value); 109 OPENSSL_free(conf->section); 110 OPENSSL_free(conf); 111 } 112 113 int X509V3_add_value_bool(const char *name, int asn1_bool, 114 STACK_OF(CONF_VALUE) **extlist) 115 { 116 if (asn1_bool) 117 return X509V3_add_value(name, "TRUE", extlist); 118 return X509V3_add_value(name, "FALSE", extlist); 119 } 120 121 int X509V3_add_value_bool_nf(const char *name, int asn1_bool, 122 STACK_OF(CONF_VALUE) **extlist) 123 { 124 if (asn1_bool) 125 return X509V3_add_value(name, "TRUE", extlist); 126 return 1; 127 } 128 129 static char *bignum_to_string(const BIGNUM *bn) 130 { 131 char *tmp, *ret; 132 size_t len; 133 134 /* 135 * Display large numbers in hex and small numbers in decimal. Converting to 136 * decimal takes quadratic time and is no more useful than hex for large 137 * numbers. 138 */ 139 if (BN_num_bits(bn) < 128) 140 return BN_bn2dec(bn); 141 142 tmp = BN_bn2hex(bn); 143 if (tmp == NULL) 144 return NULL; 145 146 len = strlen(tmp) + 3; 147 ret = OPENSSL_malloc(len); 148 if (ret == NULL) { 149 ERR_raise(ERR_LIB_X509V3, ERR_R_MALLOC_FAILURE); 150 OPENSSL_free(tmp); 151 return NULL; 152 } 153 154 /* Prepend "0x", but place it after the "-" if negative. */ 155 if (tmp[0] == '-') { 156 OPENSSL_strlcpy(ret, "-0x", len); 157 OPENSSL_strlcat(ret, tmp + 1, len); 158 } else { 159 OPENSSL_strlcpy(ret, "0x", len); 160 OPENSSL_strlcat(ret, tmp, len); 161 } 162 OPENSSL_free(tmp); 163 return ret; 164 } 165 166 char *i2s_ASN1_ENUMERATED(X509V3_EXT_METHOD *method, const ASN1_ENUMERATED *a) 167 { 168 BIGNUM *bntmp = NULL; 169 char *strtmp = NULL; 170 171 if (!a) 172 return NULL; 173 if ((bntmp = ASN1_ENUMERATED_to_BN(a, NULL)) == NULL 174 || (strtmp = bignum_to_string(bntmp)) == NULL) 175 ERR_raise(ERR_LIB_X509V3, ERR_R_MALLOC_FAILURE); 176 BN_free(bntmp); 177 return strtmp; 178 } 179 180 char *i2s_ASN1_INTEGER(X509V3_EXT_METHOD *method, const ASN1_INTEGER *a) 181 { 182 BIGNUM *bntmp = NULL; 183 char *strtmp = NULL; 184 185 if (!a) 186 return NULL; 187 if ((bntmp = ASN1_INTEGER_to_BN(a, NULL)) == NULL 188 || (strtmp = bignum_to_string(bntmp)) == NULL) 189 ERR_raise(ERR_LIB_X509V3, ERR_R_MALLOC_FAILURE); 190 BN_free(bntmp); 191 return strtmp; 192 } 193 194 ASN1_INTEGER *s2i_ASN1_INTEGER(X509V3_EXT_METHOD *method, const char *value) 195 { 196 BIGNUM *bn = NULL; 197 ASN1_INTEGER *aint; 198 int isneg, ishex; 199 int ret; 200 201 if (value == NULL) { 202 ERR_raise(ERR_LIB_X509V3, X509V3_R_INVALID_NULL_VALUE); 203 return NULL; 204 } 205 bn = BN_new(); 206 if (bn == NULL) { 207 ERR_raise(ERR_LIB_X509V3, ERR_R_MALLOC_FAILURE); 208 return NULL; 209 } 210 if (value[0] == '-') { 211 value++; 212 isneg = 1; 213 } else { 214 isneg = 0; 215 } 216 217 if (value[0] == '0' && ((value[1] == 'x') || (value[1] == 'X'))) { 218 value += 2; 219 ishex = 1; 220 } else { 221 ishex = 0; 222 } 223 224 if (ishex) 225 ret = BN_hex2bn(&bn, value); 226 else 227 ret = BN_dec2bn(&bn, value); 228 229 if (!ret || value[ret]) { 230 BN_free(bn); 231 ERR_raise(ERR_LIB_X509V3, X509V3_R_BN_DEC2BN_ERROR); 232 return NULL; 233 } 234 235 if (isneg && BN_is_zero(bn)) 236 isneg = 0; 237 238 aint = BN_to_ASN1_INTEGER(bn, NULL); 239 BN_free(bn); 240 if (!aint) { 241 ERR_raise(ERR_LIB_X509V3, X509V3_R_BN_TO_ASN1_INTEGER_ERROR); 242 return NULL; 243 } 244 if (isneg) 245 aint->type |= V_ASN1_NEG; 246 return aint; 247 } 248 249 int X509V3_add_value_int(const char *name, const ASN1_INTEGER *aint, 250 STACK_OF(CONF_VALUE) **extlist) 251 { 252 char *strtmp; 253 int ret; 254 255 if (!aint) 256 return 1; 257 if ((strtmp = i2s_ASN1_INTEGER(NULL, aint)) == NULL) 258 return 0; 259 ret = X509V3_add_value(name, strtmp, extlist); 260 OPENSSL_free(strtmp); 261 return ret; 262 } 263 264 int X509V3_get_value_bool(const CONF_VALUE *value, int *asn1_bool) 265 { 266 const char *btmp; 267 268 if ((btmp = value->value) == NULL) 269 goto err; 270 if (strcmp(btmp, "TRUE") == 0 271 || strcmp(btmp, "true") == 0 272 || strcmp(btmp, "Y") == 0 273 || strcmp(btmp, "y") == 0 274 || strcmp(btmp, "YES") == 0 275 || strcmp(btmp, "yes") == 0) { 276 *asn1_bool = 0xff; 277 return 1; 278 } 279 if (strcmp(btmp, "FALSE") == 0 280 || strcmp(btmp, "false") == 0 281 || strcmp(btmp, "N") == 0 282 || strcmp(btmp, "n") == 0 283 || strcmp(btmp, "NO") == 0 284 || strcmp(btmp, "no") == 0) { 285 *asn1_bool = 0; 286 return 1; 287 } 288 err: 289 ERR_raise(ERR_LIB_X509V3, X509V3_R_INVALID_BOOLEAN_STRING); 290 X509V3_conf_add_error_name_value(value); 291 return 0; 292 } 293 294 int X509V3_get_value_int(const CONF_VALUE *value, ASN1_INTEGER **aint) 295 { 296 ASN1_INTEGER *itmp; 297 298 if ((itmp = s2i_ASN1_INTEGER(NULL, value->value)) == NULL) { 299 X509V3_conf_add_error_name_value(value); 300 return 0; 301 } 302 *aint = itmp; 303 return 1; 304 } 305 306 #define HDR_NAME 1 307 #define HDR_VALUE 2 308 309 /* 310 * #define DEBUG 311 */ 312 313 STACK_OF(CONF_VALUE) *X509V3_parse_list(const char *line) 314 { 315 char *p, *q, c; 316 char *ntmp, *vtmp; 317 STACK_OF(CONF_VALUE) *values = NULL; 318 char *linebuf; 319 int state; 320 321 /* We are going to modify the line so copy it first */ 322 linebuf = OPENSSL_strdup(line); 323 if (linebuf == NULL) { 324 ERR_raise(ERR_LIB_X509V3, ERR_R_MALLOC_FAILURE); 325 goto err; 326 } 327 state = HDR_NAME; 328 ntmp = NULL; 329 /* Go through all characters */ 330 for (p = linebuf, q = linebuf; (c = *p) && (c != '\r') && (c != '\n'); 331 p++) { 332 333 switch (state) { 334 case HDR_NAME: 335 if (c == ':') { 336 state = HDR_VALUE; 337 *p = 0; 338 ntmp = strip_spaces(q); 339 if (!ntmp) { 340 ERR_raise(ERR_LIB_X509V3, X509V3_R_INVALID_EMPTY_NAME); 341 goto err; 342 } 343 q = p + 1; 344 } else if (c == ',') { 345 *p = 0; 346 ntmp = strip_spaces(q); 347 q = p + 1; 348 if (!ntmp) { 349 ERR_raise(ERR_LIB_X509V3, X509V3_R_INVALID_EMPTY_NAME); 350 goto err; 351 } 352 if (!X509V3_add_value(ntmp, NULL, &values)) { 353 goto err; 354 } 355 } 356 break; 357 358 case HDR_VALUE: 359 if (c == ',') { 360 state = HDR_NAME; 361 *p = 0; 362 vtmp = strip_spaces(q); 363 if (!vtmp) { 364 ERR_raise(ERR_LIB_X509V3, X509V3_R_INVALID_NULL_VALUE); 365 goto err; 366 } 367 if (!X509V3_add_value(ntmp, vtmp, &values)) { 368 goto err; 369 } 370 ntmp = NULL; 371 q = p + 1; 372 } 373 374 } 375 } 376 377 if (state == HDR_VALUE) { 378 vtmp = strip_spaces(q); 379 if (!vtmp) { 380 ERR_raise(ERR_LIB_X509V3, X509V3_R_INVALID_NULL_VALUE); 381 goto err; 382 } 383 if (!X509V3_add_value(ntmp, vtmp, &values)) { 384 goto err; 385 } 386 } else { 387 ntmp = strip_spaces(q); 388 if (!ntmp) { 389 ERR_raise(ERR_LIB_X509V3, X509V3_R_INVALID_EMPTY_NAME); 390 goto err; 391 } 392 if (!X509V3_add_value(ntmp, NULL, &values)) { 393 goto err; 394 } 395 } 396 OPENSSL_free(linebuf); 397 return values; 398 399 err: 400 OPENSSL_free(linebuf); 401 sk_CONF_VALUE_pop_free(values, X509V3_conf_free); 402 return NULL; 403 404 } 405 406 /* Delete leading and trailing spaces from a string */ 407 static char *strip_spaces(char *name) 408 { 409 char *p, *q; 410 411 /* Skip over leading spaces */ 412 p = name; 413 while (*p && ossl_isspace(*p)) 414 p++; 415 if (*p == '\0') 416 return NULL; 417 q = p + strlen(p) - 1; 418 while ((q != p) && ossl_isspace(*q)) 419 q--; 420 if (p != q) 421 q[1] = 0; 422 if (*p == '\0') 423 return NULL; 424 return p; 425 } 426 427 428 /* 429 * V2I name comparison function: returns zero if 'name' matches cmp or cmp.* 430 */ 431 432 int ossl_v3_name_cmp(const char *name, const char *cmp) 433 { 434 int len, ret; 435 char c; 436 437 len = strlen(cmp); 438 if ((ret = strncmp(name, cmp, len))) 439 return ret; 440 c = name[len]; 441 if (!c || (c == '.')) 442 return 0; 443 return 1; 444 } 445 446 static int sk_strcmp(const char *const *a, const char *const *b) 447 { 448 return strcmp(*a, *b); 449 } 450 451 STACK_OF(OPENSSL_STRING) *X509_get1_email(X509 *x) 452 { 453 GENERAL_NAMES *gens; 454 STACK_OF(OPENSSL_STRING) *ret; 455 456 gens = X509_get_ext_d2i(x, NID_subject_alt_name, NULL, NULL); 457 ret = get_email(X509_get_subject_name(x), gens); 458 sk_GENERAL_NAME_pop_free(gens, GENERAL_NAME_free); 459 return ret; 460 } 461 462 STACK_OF(OPENSSL_STRING) *X509_get1_ocsp(X509 *x) 463 { 464 AUTHORITY_INFO_ACCESS *info; 465 STACK_OF(OPENSSL_STRING) *ret = NULL; 466 int i; 467 468 info = X509_get_ext_d2i(x, NID_info_access, NULL, NULL); 469 if (!info) 470 return NULL; 471 for (i = 0; i < sk_ACCESS_DESCRIPTION_num(info); i++) { 472 ACCESS_DESCRIPTION *ad = sk_ACCESS_DESCRIPTION_value(info, i); 473 if (OBJ_obj2nid(ad->method) == NID_ad_OCSP) { 474 if (ad->location->type == GEN_URI) { 475 if (!append_ia5 476 (&ret, ad->location->d.uniformResourceIdentifier)) 477 break; 478 } 479 } 480 } 481 AUTHORITY_INFO_ACCESS_free(info); 482 return ret; 483 } 484 485 STACK_OF(OPENSSL_STRING) *X509_REQ_get1_email(X509_REQ *x) 486 { 487 GENERAL_NAMES *gens; 488 STACK_OF(X509_EXTENSION) *exts; 489 STACK_OF(OPENSSL_STRING) *ret; 490 491 exts = X509_REQ_get_extensions(x); 492 gens = X509V3_get_d2i(exts, NID_subject_alt_name, NULL, NULL); 493 ret = get_email(X509_REQ_get_subject_name(x), gens); 494 sk_GENERAL_NAME_pop_free(gens, GENERAL_NAME_free); 495 sk_X509_EXTENSION_pop_free(exts, X509_EXTENSION_free); 496 return ret; 497 } 498 499 static STACK_OF(OPENSSL_STRING) *get_email(const X509_NAME *name, 500 GENERAL_NAMES *gens) 501 { 502 STACK_OF(OPENSSL_STRING) *ret = NULL; 503 X509_NAME_ENTRY *ne; 504 const ASN1_IA5STRING *email; 505 GENERAL_NAME *gen; 506 int i = -1; 507 508 /* Now add any email address(es) to STACK */ 509 /* First supplied X509_NAME */ 510 while ((i = X509_NAME_get_index_by_NID(name, 511 NID_pkcs9_emailAddress, i)) >= 0) { 512 ne = X509_NAME_get_entry(name, i); 513 email = X509_NAME_ENTRY_get_data(ne); 514 if (!append_ia5(&ret, email)) 515 return NULL; 516 } 517 for (i = 0; i < sk_GENERAL_NAME_num(gens); i++) { 518 gen = sk_GENERAL_NAME_value(gens, i); 519 if (gen->type != GEN_EMAIL) 520 continue; 521 if (!append_ia5(&ret, gen->d.ia5)) 522 return NULL; 523 } 524 return ret; 525 } 526 527 static void str_free(OPENSSL_STRING str) 528 { 529 OPENSSL_free(str); 530 } 531 532 static int append_ia5(STACK_OF(OPENSSL_STRING) **sk, 533 const ASN1_IA5STRING *email) 534 { 535 char *emtmp; 536 537 /* First some sanity checks */ 538 if (email->type != V_ASN1_IA5STRING) 539 return 1; 540 if (email->data == NULL || email->length == 0) 541 return 1; 542 if (memchr(email->data, 0, email->length) != NULL) 543 return 1; 544 if (*sk == NULL) 545 *sk = sk_OPENSSL_STRING_new(sk_strcmp); 546 if (*sk == NULL) 547 return 0; 548 549 emtmp = OPENSSL_strndup((char *)email->data, email->length); 550 if (emtmp == NULL) { 551 X509_email_free(*sk); 552 *sk = NULL; 553 return 0; 554 } 555 556 /* Don't add duplicates */ 557 if (sk_OPENSSL_STRING_find(*sk, emtmp) != -1) { 558 OPENSSL_free(emtmp); 559 return 1; 560 } 561 if (!sk_OPENSSL_STRING_push(*sk, emtmp)) { 562 OPENSSL_free(emtmp); /* free on push failure */ 563 X509_email_free(*sk); 564 *sk = NULL; 565 return 0; 566 } 567 return 1; 568 } 569 570 void X509_email_free(STACK_OF(OPENSSL_STRING) *sk) 571 { 572 sk_OPENSSL_STRING_pop_free(sk, str_free); 573 } 574 575 typedef int (*equal_fn) (const unsigned char *pattern, size_t pattern_len, 576 const unsigned char *subject, size_t subject_len, 577 unsigned int flags); 578 579 /* Skip pattern prefix to match "wildcard" subject */ 580 static void skip_prefix(const unsigned char **p, size_t *plen, 581 size_t subject_len, 582 unsigned int flags) 583 { 584 const unsigned char *pattern = *p; 585 size_t pattern_len = *plen; 586 587 /* 588 * If subject starts with a leading '.' followed by more octets, and 589 * pattern is longer, compare just an equal-length suffix with the 590 * full subject (starting at the '.'), provided the prefix contains 591 * no NULs. 592 */ 593 if ((flags & _X509_CHECK_FLAG_DOT_SUBDOMAINS) == 0) 594 return; 595 596 while (pattern_len > subject_len && *pattern) { 597 if ((flags & X509_CHECK_FLAG_SINGLE_LABEL_SUBDOMAINS) && 598 *pattern == '.') 599 break; 600 ++pattern; 601 --pattern_len; 602 } 603 604 /* Skip if entire prefix acceptable */ 605 if (pattern_len == subject_len) { 606 *p = pattern; 607 *plen = pattern_len; 608 } 609 } 610 611 /* Compare while ASCII ignoring case. */ 612 static int equal_nocase(const unsigned char *pattern, size_t pattern_len, 613 const unsigned char *subject, size_t subject_len, 614 unsigned int flags) 615 { 616 skip_prefix(&pattern, &pattern_len, subject_len, flags); 617 if (pattern_len != subject_len) 618 return 0; 619 while (pattern_len != 0) { 620 unsigned char l = *pattern; 621 unsigned char r = *subject; 622 623 /* The pattern must not contain NUL characters. */ 624 if (l == 0) 625 return 0; 626 if (l != r) { 627 if ('A' <= l && l <= 'Z') 628 l = (l - 'A') + 'a'; 629 if ('A' <= r && r <= 'Z') 630 r = (r - 'A') + 'a'; 631 if (l != r) 632 return 0; 633 } 634 ++pattern; 635 ++subject; 636 --pattern_len; 637 } 638 return 1; 639 } 640 641 /* Compare using memcmp. */ 642 static int equal_case(const unsigned char *pattern, size_t pattern_len, 643 const unsigned char *subject, size_t subject_len, 644 unsigned int flags) 645 { 646 skip_prefix(&pattern, &pattern_len, subject_len, flags); 647 if (pattern_len != subject_len) 648 return 0; 649 return !memcmp(pattern, subject, pattern_len); 650 } 651 652 /* 653 * RFC 5280, section 7.5, requires that only the domain is compared in a 654 * case-insensitive manner. 655 */ 656 static int equal_email(const unsigned char *a, size_t a_len, 657 const unsigned char *b, size_t b_len, 658 unsigned int unused_flags) 659 { 660 size_t i = a_len; 661 662 if (a_len != b_len) 663 return 0; 664 /* 665 * We search backwards for the '@' character, so that we do not have to 666 * deal with quoted local-parts. The domain part is compared in a 667 * case-insensitive manner. 668 */ 669 while (i > 0) { 670 --i; 671 if (a[i] == '@' || b[i] == '@') { 672 if (!equal_nocase(a + i, a_len - i, b + i, a_len - i, 0)) 673 return 0; 674 break; 675 } 676 } 677 if (i == 0) 678 i = a_len; 679 return equal_case(a, i, b, i, 0); 680 } 681 682 /* 683 * Compare the prefix and suffix with the subject, and check that the 684 * characters in-between are valid. 685 */ 686 static int wildcard_match(const unsigned char *prefix, size_t prefix_len, 687 const unsigned char *suffix, size_t suffix_len, 688 const unsigned char *subject, size_t subject_len, 689 unsigned int flags) 690 { 691 const unsigned char *wildcard_start; 692 const unsigned char *wildcard_end; 693 const unsigned char *p; 694 int allow_multi = 0; 695 int allow_idna = 0; 696 697 if (subject_len < prefix_len + suffix_len) 698 return 0; 699 if (!equal_nocase(prefix, prefix_len, subject, prefix_len, flags)) 700 return 0; 701 wildcard_start = subject + prefix_len; 702 wildcard_end = subject + (subject_len - suffix_len); 703 if (!equal_nocase(wildcard_end, suffix_len, suffix, suffix_len, flags)) 704 return 0; 705 /* 706 * If the wildcard makes up the entire first label, it must match at 707 * least one character. 708 */ 709 if (prefix_len == 0 && *suffix == '.') { 710 if (wildcard_start == wildcard_end) 711 return 0; 712 allow_idna = 1; 713 if (flags & X509_CHECK_FLAG_MULTI_LABEL_WILDCARDS) 714 allow_multi = 1; 715 } 716 /* IDNA labels cannot match partial wildcards */ 717 if (!allow_idna && 718 subject_len >= 4 && OPENSSL_strncasecmp((char *)subject, "xn--", 4) == 0) 719 return 0; 720 /* The wildcard may match a literal '*' */ 721 if (wildcard_end == wildcard_start + 1 && *wildcard_start == '*') 722 return 1; 723 /* 724 * Check that the part matched by the wildcard contains only 725 * permitted characters and only matches a single label unless 726 * allow_multi is set. 727 */ 728 for (p = wildcard_start; p != wildcard_end; ++p) 729 if (!(('0' <= *p && *p <= '9') || 730 ('A' <= *p && *p <= 'Z') || 731 ('a' <= *p && *p <= 'z') || 732 *p == '-' || (allow_multi && *p == '.'))) 733 return 0; 734 return 1; 735 } 736 737 #define LABEL_START (1 << 0) 738 #define LABEL_END (1 << 1) 739 #define LABEL_HYPHEN (1 << 2) 740 #define LABEL_IDNA (1 << 3) 741 742 static const unsigned char *valid_star(const unsigned char *p, size_t len, 743 unsigned int flags) 744 { 745 const unsigned char *star = 0; 746 size_t i; 747 int state = LABEL_START; 748 int dots = 0; 749 750 for (i = 0; i < len; ++i) { 751 /* 752 * Locate first and only legal wildcard, either at the start 753 * or end of a non-IDNA first and not final label. 754 */ 755 if (p[i] == '*') { 756 int atstart = (state & LABEL_START); 757 int atend = (i == len - 1 || p[i + 1] == '.'); 758 /*- 759 * At most one wildcard per pattern. 760 * No wildcards in IDNA labels. 761 * No wildcards after the first label. 762 */ 763 if (star != NULL || (state & LABEL_IDNA) != 0 || dots) 764 return NULL; 765 /* Only full-label '*.example.com' wildcards? */ 766 if ((flags & X509_CHECK_FLAG_NO_PARTIAL_WILDCARDS) 767 && (!atstart || !atend)) 768 return NULL; 769 /* No 'foo*bar' wildcards */ 770 if (!atstart && !atend) 771 return NULL; 772 star = &p[i]; 773 state &= ~LABEL_START; 774 } else if (('a' <= p[i] && p[i] <= 'z') 775 || ('A' <= p[i] && p[i] <= 'Z') 776 || ('0' <= p[i] && p[i] <= '9')) { 777 if ((state & LABEL_START) != 0 778 && len - i >= 4 && OPENSSL_strncasecmp((char *)&p[i], "xn--", 4) == 0) 779 state |= LABEL_IDNA; 780 state &= ~(LABEL_HYPHEN | LABEL_START); 781 } else if (p[i] == '.') { 782 if ((state & (LABEL_HYPHEN | LABEL_START)) != 0) 783 return NULL; 784 state = LABEL_START; 785 ++dots; 786 } else if (p[i] == '-') { 787 /* no domain/subdomain starts with '-' */ 788 if ((state & LABEL_START) != 0) 789 return NULL; 790 state |= LABEL_HYPHEN; 791 } else { 792 return NULL; 793 } 794 } 795 796 /* 797 * The final label must not end in a hyphen or ".", and 798 * there must be at least two dots after the star. 799 */ 800 if ((state & (LABEL_START | LABEL_HYPHEN)) != 0 || dots < 2) 801 return NULL; 802 return star; 803 } 804 805 /* Compare using wildcards. */ 806 static int equal_wildcard(const unsigned char *pattern, size_t pattern_len, 807 const unsigned char *subject, size_t subject_len, 808 unsigned int flags) 809 { 810 const unsigned char *star = NULL; 811 812 /* 813 * Subject names starting with '.' can only match a wildcard pattern 814 * via a subject sub-domain pattern suffix match. 815 */ 816 if (!(subject_len > 1 && subject[0] == '.')) 817 star = valid_star(pattern, pattern_len, flags); 818 if (star == NULL) 819 return equal_nocase(pattern, pattern_len, 820 subject, subject_len, flags); 821 return wildcard_match(pattern, star - pattern, 822 star + 1, (pattern + pattern_len) - star - 1, 823 subject, subject_len, flags); 824 } 825 826 /* 827 * Compare an ASN1_STRING to a supplied string. If they match return 1. If 828 * cmp_type > 0 only compare if string matches the type, otherwise convert it 829 * to UTF8. 830 */ 831 832 static int do_check_string(const ASN1_STRING *a, int cmp_type, equal_fn equal, 833 unsigned int flags, const char *b, size_t blen, 834 char **peername) 835 { 836 int rv = 0; 837 838 if (!a->data || !a->length) 839 return 0; 840 if (cmp_type > 0) { 841 if (cmp_type != a->type) 842 return 0; 843 if (cmp_type == V_ASN1_IA5STRING) 844 rv = equal(a->data, a->length, (unsigned char *)b, blen, flags); 845 else if (a->length == (int)blen && !memcmp(a->data, b, blen)) 846 rv = 1; 847 if (rv > 0 && peername != NULL) { 848 *peername = OPENSSL_strndup((char *)a->data, a->length); 849 if (*peername == NULL) 850 return -1; 851 } 852 } else { 853 int astrlen; 854 unsigned char *astr; 855 astrlen = ASN1_STRING_to_UTF8(&astr, a); 856 if (astrlen < 0) { 857 /* 858 * -1 could be an internal malloc failure or a decoding error from 859 * malformed input; we can't distinguish. 860 */ 861 return -1; 862 } 863 rv = equal(astr, astrlen, (unsigned char *)b, blen, flags); 864 if (rv > 0 && peername != NULL) { 865 *peername = OPENSSL_strndup((char *)astr, astrlen); 866 if (*peername == NULL) { 867 OPENSSL_free(astr); 868 return -1; 869 } 870 } 871 OPENSSL_free(astr); 872 } 873 return rv; 874 } 875 876 static int do_x509_check(X509 *x, const char *chk, size_t chklen, 877 unsigned int flags, int check_type, char **peername) 878 { 879 GENERAL_NAMES *gens = NULL; 880 const X509_NAME *name = NULL; 881 int i; 882 int cnid = NID_undef; 883 int alt_type; 884 int san_present = 0; 885 int rv = 0; 886 equal_fn equal; 887 888 /* See below, this flag is internal-only */ 889 flags &= ~_X509_CHECK_FLAG_DOT_SUBDOMAINS; 890 if (check_type == GEN_EMAIL) { 891 cnid = NID_pkcs9_emailAddress; 892 alt_type = V_ASN1_IA5STRING; 893 equal = equal_email; 894 } else if (check_type == GEN_DNS) { 895 cnid = NID_commonName; 896 /* Implicit client-side DNS sub-domain pattern */ 897 if (chklen > 1 && chk[0] == '.') 898 flags |= _X509_CHECK_FLAG_DOT_SUBDOMAINS; 899 alt_type = V_ASN1_IA5STRING; 900 if (flags & X509_CHECK_FLAG_NO_WILDCARDS) 901 equal = equal_nocase; 902 else 903 equal = equal_wildcard; 904 } else { 905 alt_type = V_ASN1_OCTET_STRING; 906 equal = equal_case; 907 } 908 909 if (chklen == 0) 910 chklen = strlen(chk); 911 912 gens = X509_get_ext_d2i(x, NID_subject_alt_name, NULL, NULL); 913 if (gens) { 914 for (i = 0; i < sk_GENERAL_NAME_num(gens); i++) { 915 GENERAL_NAME *gen; 916 ASN1_STRING *cstr; 917 918 gen = sk_GENERAL_NAME_value(gens, i); 919 switch (gen->type) { 920 default: 921 continue; 922 case GEN_OTHERNAME: 923 switch (OBJ_obj2nid(gen->d.otherName->type_id)) { 924 default: 925 continue; 926 case NID_id_on_SmtpUTF8Mailbox: 927 /*- 928 * https://datatracker.ietf.org/doc/html/rfc8398#section-3 929 * 930 * Due to name constraint compatibility reasons described 931 * in Section 6, SmtpUTF8Mailbox subjectAltName MUST NOT 932 * be used unless the local-part of the email address 933 * contains non-ASCII characters. When the local-part is 934 * ASCII, rfc822Name subjectAltName MUST be used instead 935 * of SmtpUTF8Mailbox. This is compatible with legacy 936 * software that supports only rfc822Name (and not 937 * SmtpUTF8Mailbox). [...] 938 * 939 * SmtpUTF8Mailbox is encoded as UTF8String. 940 * 941 * If it is not a UTF8String then that is unexpected, and 942 * we ignore the invalid SAN (neither set san_present nor 943 * consider it a candidate for equality). This does mean 944 * that the subject CN may be considered, as would be the 945 * case when the malformed SmtpUtf8Mailbox SAN is instead 946 * simply absent. 947 * 948 * When CN-ID matching is not desirable, applications can 949 * choose to turn it off, doing so is at this time a best 950 * practice. 951 */ 952 if (check_type != GEN_EMAIL 953 || gen->d.otherName->value->type != V_ASN1_UTF8STRING) 954 continue; 955 alt_type = 0; 956 cstr = gen->d.otherName->value->value.utf8string; 957 break; 958 } 959 break; 960 case GEN_EMAIL: 961 if (check_type != GEN_EMAIL) 962 continue; 963 cstr = gen->d.rfc822Name; 964 break; 965 case GEN_DNS: 966 if (check_type != GEN_DNS) 967 continue; 968 cstr = gen->d.dNSName; 969 break; 970 case GEN_IPADD: 971 if (check_type != GEN_IPADD) 972 continue; 973 cstr = gen->d.iPAddress; 974 break; 975 } 976 san_present = 1; 977 /* Positive on success, negative on error! */ 978 if ((rv = do_check_string(cstr, alt_type, equal, flags, 979 chk, chklen, peername)) != 0) 980 break; 981 } 982 GENERAL_NAMES_free(gens); 983 if (rv != 0) 984 return rv; 985 if (san_present && !(flags & X509_CHECK_FLAG_ALWAYS_CHECK_SUBJECT)) 986 return 0; 987 } 988 989 /* We're done if CN-ID is not pertinent */ 990 if (cnid == NID_undef || (flags & X509_CHECK_FLAG_NEVER_CHECK_SUBJECT)) 991 return 0; 992 993 i = -1; 994 name = X509_get_subject_name(x); 995 while ((i = X509_NAME_get_index_by_NID(name, cnid, i)) >= 0) { 996 const X509_NAME_ENTRY *ne = X509_NAME_get_entry(name, i); 997 const ASN1_STRING *str = X509_NAME_ENTRY_get_data(ne); 998 999 /* Positive on success, negative on error! */ 1000 if ((rv = do_check_string(str, -1, equal, flags, 1001 chk, chklen, peername)) != 0) 1002 return rv; 1003 } 1004 return 0; 1005 } 1006 1007 int X509_check_host(X509 *x, const char *chk, size_t chklen, 1008 unsigned int flags, char **peername) 1009 { 1010 if (chk == NULL) 1011 return -2; 1012 /* 1013 * Embedded NULs are disallowed, except as the last character of a 1014 * string of length 2 or more (tolerate caller including terminating 1015 * NUL in string length). 1016 */ 1017 if (chklen == 0) 1018 chklen = strlen(chk); 1019 else if (memchr(chk, '\0', chklen > 1 ? chklen - 1 : chklen)) 1020 return -2; 1021 if (chklen > 1 && chk[chklen - 1] == '\0') 1022 --chklen; 1023 return do_x509_check(x, chk, chklen, flags, GEN_DNS, peername); 1024 } 1025 1026 int X509_check_email(X509 *x, const char *chk, size_t chklen, 1027 unsigned int flags) 1028 { 1029 if (chk == NULL) 1030 return -2; 1031 /* 1032 * Embedded NULs are disallowed, except as the last character of a 1033 * string of length 2 or more (tolerate caller including terminating 1034 * NUL in string length). 1035 */ 1036 if (chklen == 0) 1037 chklen = strlen((char *)chk); 1038 else if (memchr(chk, '\0', chklen > 1 ? chklen - 1 : chklen)) 1039 return -2; 1040 if (chklen > 1 && chk[chklen - 1] == '\0') 1041 --chklen; 1042 return do_x509_check(x, chk, chklen, flags, GEN_EMAIL, NULL); 1043 } 1044 1045 int X509_check_ip(X509 *x, const unsigned char *chk, size_t chklen, 1046 unsigned int flags) 1047 { 1048 if (chk == NULL) 1049 return -2; 1050 return do_x509_check(x, (char *)chk, chklen, flags, GEN_IPADD, NULL); 1051 } 1052 1053 int X509_check_ip_asc(X509 *x, const char *ipasc, unsigned int flags) 1054 { 1055 unsigned char ipout[16]; 1056 size_t iplen; 1057 1058 if (ipasc == NULL) 1059 return -2; 1060 iplen = (size_t)ossl_a2i_ipadd(ipout, ipasc); 1061 if (iplen == 0) 1062 return -2; 1063 return do_x509_check(x, (char *)ipout, iplen, flags, GEN_IPADD, NULL); 1064 } 1065 1066 char *ossl_ipaddr_to_asc(unsigned char *p, int len) 1067 { 1068 /* 1069 * 40 is enough space for the longest IPv6 address + nul terminator byte 1070 * XXXX:XXXX:XXXX:XXXX:XXXX:XXXX:XXXX:XXXX\0 1071 */ 1072 char buf[40], *out; 1073 int i = 0, remain = 0, bytes = 0; 1074 1075 switch (len) { 1076 case 4: /* IPv4 */ 1077 BIO_snprintf(buf, sizeof(buf), "%d.%d.%d.%d", p[0], p[1], p[2], p[3]); 1078 break; 1079 case 16: /* IPv6 */ 1080 for (out = buf, i = 8, remain = sizeof(buf); 1081 i-- > 0 && bytes >= 0; 1082 remain -= bytes, out += bytes) { 1083 const char *template = (i > 0 ? "%X:" : "%X"); 1084 1085 bytes = BIO_snprintf(out, remain, template, p[0] << 8 | p[1]); 1086 p += 2; 1087 } 1088 break; 1089 default: 1090 BIO_snprintf(buf, sizeof(buf), "<invalid length=%d>", len); 1091 break; 1092 } 1093 return OPENSSL_strdup(buf); 1094 } 1095 1096 /* 1097 * Convert IP addresses both IPv4 and IPv6 into an OCTET STRING compatible 1098 * with RFC3280. 1099 */ 1100 1101 ASN1_OCTET_STRING *a2i_IPADDRESS(const char *ipasc) 1102 { 1103 unsigned char ipout[16]; 1104 ASN1_OCTET_STRING *ret; 1105 int iplen; 1106 1107 /* If string contains a ':' assume IPv6 */ 1108 1109 iplen = ossl_a2i_ipadd(ipout, ipasc); 1110 1111 if (!iplen) 1112 return NULL; 1113 1114 ret = ASN1_OCTET_STRING_new(); 1115 if (ret == NULL) 1116 return NULL; 1117 if (!ASN1_OCTET_STRING_set(ret, ipout, iplen)) { 1118 ASN1_OCTET_STRING_free(ret); 1119 return NULL; 1120 } 1121 return ret; 1122 } 1123 1124 ASN1_OCTET_STRING *a2i_IPADDRESS_NC(const char *ipasc) 1125 { 1126 ASN1_OCTET_STRING *ret = NULL; 1127 unsigned char ipout[32]; 1128 char *iptmp = NULL, *p; 1129 int iplen1, iplen2; 1130 1131 p = strchr(ipasc, '/'); 1132 if (p == NULL) 1133 return NULL; 1134 iptmp = OPENSSL_strdup(ipasc); 1135 if (iptmp == NULL) 1136 return NULL; 1137 p = iptmp + (p - ipasc); 1138 *p++ = 0; 1139 1140 iplen1 = ossl_a2i_ipadd(ipout, iptmp); 1141 1142 if (!iplen1) 1143 goto err; 1144 1145 iplen2 = ossl_a2i_ipadd(ipout + iplen1, p); 1146 1147 OPENSSL_free(iptmp); 1148 iptmp = NULL; 1149 1150 if (!iplen2 || (iplen1 != iplen2)) 1151 goto err; 1152 1153 ret = ASN1_OCTET_STRING_new(); 1154 if (ret == NULL) 1155 goto err; 1156 if (!ASN1_OCTET_STRING_set(ret, ipout, iplen1 + iplen2)) 1157 goto err; 1158 1159 return ret; 1160 1161 err: 1162 OPENSSL_free(iptmp); 1163 ASN1_OCTET_STRING_free(ret); 1164 return NULL; 1165 } 1166 1167 int ossl_a2i_ipadd(unsigned char *ipout, const char *ipasc) 1168 { 1169 /* If string contains a ':' assume IPv6 */ 1170 1171 if (strchr(ipasc, ':')) { 1172 if (!ipv6_from_asc(ipout, ipasc)) 1173 return 0; 1174 return 16; 1175 } else { 1176 if (!ipv4_from_asc(ipout, ipasc)) 1177 return 0; 1178 return 4; 1179 } 1180 } 1181 1182 static int ipv4_from_asc(unsigned char *v4, const char *in) 1183 { 1184 const char *p; 1185 int a0, a1, a2, a3, n; 1186 1187 if (sscanf(in, "%d.%d.%d.%d%n", &a0, &a1, &a2, &a3, &n) != 4) 1188 return 0; 1189 if ((a0 < 0) || (a0 > 255) || (a1 < 0) || (a1 > 255) 1190 || (a2 < 0) || (a2 > 255) || (a3 < 0) || (a3 > 255)) 1191 return 0; 1192 p = in + n; 1193 if (!(*p == '\0' || ossl_isspace(*p))) 1194 return 0; 1195 v4[0] = a0; 1196 v4[1] = a1; 1197 v4[2] = a2; 1198 v4[3] = a3; 1199 return 1; 1200 } 1201 1202 typedef struct { 1203 /* Temporary store for IPV6 output */ 1204 unsigned char tmp[16]; 1205 /* Total number of bytes in tmp */ 1206 int total; 1207 /* The position of a zero (corresponding to '::') */ 1208 int zero_pos; 1209 /* Number of zeroes */ 1210 int zero_cnt; 1211 } IPV6_STAT; 1212 1213 static int ipv6_from_asc(unsigned char *v6, const char *in) 1214 { 1215 IPV6_STAT v6stat; 1216 1217 v6stat.total = 0; 1218 v6stat.zero_pos = -1; 1219 v6stat.zero_cnt = 0; 1220 /* 1221 * Treat the IPv6 representation as a list of values separated by ':'. 1222 * The presence of a '::' will parse as one, two or three zero length 1223 * elements. 1224 */ 1225 if (!CONF_parse_list(in, ':', 0, ipv6_cb, &v6stat)) 1226 return 0; 1227 1228 /* Now for some sanity checks */ 1229 1230 if (v6stat.zero_pos == -1) { 1231 /* If no '::' must have exactly 16 bytes */ 1232 if (v6stat.total != 16) 1233 return 0; 1234 } else { 1235 /* If '::' must have less than 16 bytes */ 1236 if (v6stat.total == 16) 1237 return 0; 1238 /* More than three zeroes is an error */ 1239 if (v6stat.zero_cnt > 3) { 1240 return 0; 1241 /* Can only have three zeroes if nothing else present */ 1242 } else if (v6stat.zero_cnt == 3) { 1243 if (v6stat.total > 0) 1244 return 0; 1245 } else if (v6stat.zero_cnt == 2) { 1246 /* Can only have two zeroes if at start or end */ 1247 if ((v6stat.zero_pos != 0) 1248 && (v6stat.zero_pos != v6stat.total)) 1249 return 0; 1250 } else { 1251 /* Can only have one zero if *not* start or end */ 1252 if ((v6stat.zero_pos == 0) 1253 || (v6stat.zero_pos == v6stat.total)) 1254 return 0; 1255 } 1256 } 1257 1258 /* Format result */ 1259 1260 if (v6stat.zero_pos >= 0) { 1261 /* Copy initial part */ 1262 memcpy(v6, v6stat.tmp, v6stat.zero_pos); 1263 /* Zero middle */ 1264 memset(v6 + v6stat.zero_pos, 0, 16 - v6stat.total); 1265 /* Copy final part */ 1266 if (v6stat.total != v6stat.zero_pos) 1267 memcpy(v6 + v6stat.zero_pos + 16 - v6stat.total, 1268 v6stat.tmp + v6stat.zero_pos, 1269 v6stat.total - v6stat.zero_pos); 1270 } else { 1271 memcpy(v6, v6stat.tmp, 16); 1272 } 1273 1274 return 1; 1275 } 1276 1277 static int ipv6_cb(const char *elem, int len, void *usr) 1278 { 1279 IPV6_STAT *s = usr; 1280 1281 /* Error if 16 bytes written */ 1282 if (s->total == 16) 1283 return 0; 1284 if (len == 0) { 1285 /* Zero length element, corresponds to '::' */ 1286 if (s->zero_pos == -1) 1287 s->zero_pos = s->total; 1288 /* If we've already got a :: its an error */ 1289 else if (s->zero_pos != s->total) 1290 return 0; 1291 s->zero_cnt++; 1292 } else { 1293 /* If more than 4 characters could be final a.b.c.d form */ 1294 if (len > 4) { 1295 /* Need at least 4 bytes left */ 1296 if (s->total > 12) 1297 return 0; 1298 /* Must be end of string */ 1299 if (elem[len]) 1300 return 0; 1301 if (!ipv4_from_asc(s->tmp + s->total, elem)) 1302 return 0; 1303 s->total += 4; 1304 } else { 1305 if (!ipv6_hex(s->tmp + s->total, elem, len)) 1306 return 0; 1307 s->total += 2; 1308 } 1309 } 1310 return 1; 1311 } 1312 1313 /* 1314 * Convert a string of up to 4 hex digits into the corresponding IPv6 form. 1315 */ 1316 1317 static int ipv6_hex(unsigned char *out, const char *in, int inlen) 1318 { 1319 unsigned char c; 1320 unsigned int num = 0; 1321 int x; 1322 1323 if (inlen > 4) 1324 return 0; 1325 while (inlen--) { 1326 c = *in++; 1327 num <<= 4; 1328 x = OPENSSL_hexchar2int(c); 1329 if (x < 0) 1330 return 0; 1331 num |= (char)x; 1332 } 1333 out[0] = num >> 8; 1334 out[1] = num & 0xff; 1335 return 1; 1336 } 1337 1338 int X509V3_NAME_from_section(X509_NAME *nm, STACK_OF(CONF_VALUE) *dn_sk, 1339 unsigned long chtype) 1340 { 1341 CONF_VALUE *v; 1342 int i, mval, spec_char, plus_char; 1343 char *p, *type; 1344 1345 if (!nm) 1346 return 0; 1347 1348 for (i = 0; i < sk_CONF_VALUE_num(dn_sk); i++) { 1349 v = sk_CONF_VALUE_value(dn_sk, i); 1350 type = v->name; 1351 /* 1352 * Skip past any leading X. X: X, etc to allow for multiple instances 1353 */ 1354 for (p = type; *p; p++) { 1355 #ifndef CHARSET_EBCDIC 1356 spec_char = ((*p == ':') || (*p == ',') || (*p == '.')); 1357 #else 1358 spec_char = ((*p == os_toascii[':']) || (*p == os_toascii[',']) 1359 || (*p == os_toascii['.'])); 1360 #endif 1361 if (spec_char) { 1362 p++; 1363 if (*p) 1364 type = p; 1365 break; 1366 } 1367 } 1368 #ifndef CHARSET_EBCDIC 1369 plus_char = (*type == '+'); 1370 #else 1371 plus_char = (*type == os_toascii['+']); 1372 #endif 1373 if (plus_char) { 1374 mval = -1; 1375 type++; 1376 } else { 1377 mval = 0; 1378 } 1379 if (!X509_NAME_add_entry_by_txt(nm, type, chtype, 1380 (unsigned char *)v->value, -1, -1, 1381 mval)) 1382 return 0; 1383 1384 } 1385 return 1; 1386 } 1387