crypto/x509v3/v3_asid.c

   1 /*
   2  * Copyright 2006-2016 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the OpenSSL license (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 /*
  11  * Implementation of RFC 3779 section 3.2.
  12  */
  13
  14 #include <assert.h>
  15 #include <stdio.h>
  16 #include <string.h>
  17 #include "internal/cryptlib.h"
  18 #include <openssl/conf.h>
  19 #include <openssl/asn1.h>
  20 #include <openssl/asn1t.h>
  21 #include <openssl/x509v3.h>
  22 #include <openssl/x509.h>
  23 #include "internal/x509_int.h"
  24 #include <openssl/bn.h>
  25 #include "ext_dat.h"
  26
  27 #ifndef OPENSSL_NO_RFC3779
  28
  29 /*
  30  * OpenSSL ASN.1 template translation of RFC 3779 3.2.3.
  31  */
  32
  33 ASN1_SEQUENCE(ASRange) = {
  34   ASN1_SIMPLE(ASRange, min, ASN1_INTEGER),
  35   ASN1_SIMPLE(ASRange, max, ASN1_INTEGER)
  36 } ASN1_SEQUENCE_END(ASRange)
  37
  38 ASN1_CHOICE(ASIdOrRange) = {
  39   ASN1_SIMPLE(ASIdOrRange, u.id,    ASN1_INTEGER),
  40   ASN1_SIMPLE(ASIdOrRange, u.range, ASRange)
  41 } ASN1_CHOICE_END(ASIdOrRange)
  42
  43 ASN1_CHOICE(ASIdentifierChoice) = {
  44   ASN1_SIMPLE(ASIdentifierChoice,      u.inherit,       ASN1_NULL),
  45   ASN1_SEQUENCE_OF(ASIdentifierChoice, u.asIdsOrRanges, ASIdOrRange)
  46 } ASN1_CHOICE_END(ASIdentifierChoice)
  47
  48 ASN1_SEQUENCE(ASIdentifiers) = {
  49   ASN1_EXP_OPT(ASIdentifiers, asnum, ASIdentifierChoice, 0),
  50   ASN1_EXP_OPT(ASIdentifiers, rdi,   ASIdentifierChoice, 1)
  51 } ASN1_SEQUENCE_END(ASIdentifiers)
  52
  53 IMPLEMENT_ASN1_FUNCTIONS(ASRange)
  54 IMPLEMENT_ASN1_FUNCTIONS(ASIdOrRange)
  55 IMPLEMENT_ASN1_FUNCTIONS(ASIdentifierChoice)
  56 IMPLEMENT_ASN1_FUNCTIONS(ASIdentifiers)
  57
  58 /*
  59  * i2r method for an ASIdentifierChoice.
  60  */
  61 static int i2r_ASIdentifierChoice(BIO *out,
  62                                   ASIdentifierChoice *choice,
  63                                   int indent, const char *msg)
  64 {
  65     int i;
  66     char *s;
  67     if (choice == NULL)
  68         return 1;
  69     BIO_printf(out, "%*s%s:\n", indent, "", msg);
  70     switch (choice->type) {
  71     case ASIdentifierChoice_inherit:
  72         BIO_printf(out, "%*sinherit\n", indent + 2, "");
  73         break;
  74     case ASIdentifierChoice_asIdsOrRanges:
  75         for (i = 0; i < sk_ASIdOrRange_num(choice->u.asIdsOrRanges); i++) {
  76             ASIdOrRange *aor =
  77                 sk_ASIdOrRange_value(choice->u.asIdsOrRanges, i);
  78             switch (aor->type) {
  79             case ASIdOrRange_id:
  80                 if ((s = i2s_ASN1_INTEGER(NULL, aor->u.id)) == NULL)
  81                     return 0;
  82                 BIO_printf(out, "%*s%s\n", indent + 2, "", s);
  83                 OPENSSL_free(s);
  84                 break;
  85             case ASIdOrRange_range:
  86                 if ((s = i2s_ASN1_INTEGER(NULL, aor->u.range->min)) == NULL)
  87                     return 0;
  88                 BIO_printf(out, "%*s%s-", indent + 2, "", s);
  89                 OPENSSL_free(s);
  90                 if ((s = i2s_ASN1_INTEGER(NULL, aor->u.range->max)) == NULL)
  91                     return 0;
  92                 BIO_printf(out, "%s\n", s);
  93                 OPENSSL_free(s);
  94                 break;
  95             default:
  96                 return 0;
  97             }
  98         }
  99         break;
 100     default:
 101         return 0;
 102     }
 103     return 1;
 104 }
 105
 106 /*
 107  * i2r method for an ASIdentifier extension.
 108  */
 109 static int i2r_ASIdentifiers(const X509V3_EXT_METHOD *method,
 110                              void *ext, BIO *out, int indent)
 111 {
 112     ASIdentifiers *asid = ext;
 113     return (i2r_ASIdentifierChoice(out, asid->asnum, indent,
 114                                    "Autonomous System Numbers") &&
 115             i2r_ASIdentifierChoice(out, asid->rdi, indent,
 116                                    "Routing Domain Identifiers"));
 117 }
 118
 119 /*
 120  * Sort comparison function for a sequence of ASIdOrRange elements.
 121  */
 122 static int ASIdOrRange_cmp(const ASIdOrRange *const *a_,
 123                            const ASIdOrRange *const *b_)
 124 {
 125     const ASIdOrRange *a = *a_, *b = *b_;
 126
 127     assert((a->type == ASIdOrRange_id && a->u.id != NULL) ||
 128            (a->type == ASIdOrRange_range && a->u.range != NULL &&
 129             a->u.range->min != NULL && a->u.range->max != NULL));
 130
 131     assert((b->type == ASIdOrRange_id && b->u.id != NULL) ||
 132            (b->type == ASIdOrRange_range && b->u.range != NULL &&
 133             b->u.range->min != NULL && b->u.range->max != NULL));
 134
 135     if (a->type == ASIdOrRange_id && b->type == ASIdOrRange_id)
 136         return ASN1_INTEGER_cmp(a->u.id, b->u.id);
 137
 138     if (a->type == ASIdOrRange_range && b->type == ASIdOrRange_range) {
 139         int r = ASN1_INTEGER_cmp(a->u.range->min, b->u.range->min);
 140         return r != 0 ? r : ASN1_INTEGER_cmp(a->u.range->max,
 141                                              b->u.range->max);
 142     }
 143
 144     if (a->type == ASIdOrRange_id)
 145         return ASN1_INTEGER_cmp(a->u.id, b->u.range->min);
 146     else
 147         return ASN1_INTEGER_cmp(a->u.range->min, b->u.id);
 148 }
 149
 150 /*
 151  * Add an inherit element.
 152  */
 153 int X509v3_asid_add_inherit(ASIdentifiers *asid, int which)
 154 {
 155     ASIdentifierChoice **choice;
 156     if (asid == NULL)
 157         return 0;
 158     switch (which) {
 159     case V3_ASID_ASNUM:
 160         choice = &asid->asnum;
 161         break;
 162     case V3_ASID_RDI:
 163         choice = &asid->rdi;
 164         break;
 165     default:
 166         return 0;
 167     }
 168     if (*choice == NULL) {
 169         if ((*choice = ASIdentifierChoice_new()) == NULL)
 170             return 0;
 171         if (!ossl_assert((*choice)->u.inherit == NULL))
 172             return 0;
 173         if (((*choice)->u.inherit = ASN1_NULL_new()) == NULL)
 174             return 0;
 175         (*choice)->type = ASIdentifierChoice_inherit;
 176     }
 177     return (*choice)->type == ASIdentifierChoice_inherit;
 178 }
 179
 180 /*
 181  * Add an ID or range to an ASIdentifierChoice.
 182  */
 183 int X509v3_asid_add_id_or_range(ASIdentifiers *asid,
 184                                 int which, ASN1_INTEGER *min, ASN1_INTEGER *max)
 185 {
 186     ASIdentifierChoice **choice;
 187     ASIdOrRange *aor;
 188     if (asid == NULL)
 189         return 0;
 190     switch (which) {
 191     case V3_ASID_ASNUM:
 192         choice = &asid->asnum;
 193         break;
 194     case V3_ASID_RDI:
 195         choice = &asid->rdi;
 196         break;
 197     default:
 198         return 0;
 199     }
 200     if (*choice != NULL && (*choice)->type == ASIdentifierChoice_inherit)
 201         return 0;
 202     if (*choice == NULL) {
 203         if ((*choice = ASIdentifierChoice_new()) == NULL)
 204             return 0;
 205         if (!ossl_assert((*choice)->u.asIdsOrRanges == NULL))
 206             return 0;
 207         (*choice)->u.asIdsOrRanges = sk_ASIdOrRange_new(ASIdOrRange_cmp);
 208         if ((*choice)->u.asIdsOrRanges == NULL)
 209             return 0;
 210         (*choice)->type = ASIdentifierChoice_asIdsOrRanges;
 211     }
 212     if ((aor = ASIdOrRange_new()) == NULL)
 213         return 0;
 214     if (max == NULL) {
 215         aor->type = ASIdOrRange_id;
 216         aor->u.id = min;
 217     } else {
 218         aor->type = ASIdOrRange_range;
 219         if ((aor->u.range = ASRange_new()) == NULL)
 220             goto err;
 221         ASN1_INTEGER_free(aor->u.range->min);
 222         aor->u.range->min = min;
 223         ASN1_INTEGER_free(aor->u.range->max);
 224         aor->u.range->max = max;
 225     }
 226     if (!(sk_ASIdOrRange_push((*choice)->u.asIdsOrRanges, aor)))
 227         goto err;
 228     return 1;
 229
 230  err:
 231     ASIdOrRange_free(aor);
 232     return 0;
 233 }
 234
 235 /*
 236  * Extract min and max values from an ASIdOrRange.
 237  */
 238 static int extract_min_max(ASIdOrRange *aor,
 239                            ASN1_INTEGER **min, ASN1_INTEGER **max)
 240 {
 241     if (!ossl_assert(aor != NULL && min != NULL && max != NULL))
 242         return 0;
 243     switch (aor->type) {
 244     case ASIdOrRange_id:
 245         *min = aor->u.id;
 246         *max = aor->u.id;
 247         return 1;
 248     case ASIdOrRange_range:
 249         *min = aor->u.range->min;
 250         *max = aor->u.range->max;
 251         return 1;
 252     }
 253
 254     return 0;
 255 }
 256
 257 /*
 258  * Check whether an ASIdentifierChoice is in canonical form.
 259  */
 260 static int ASIdentifierChoice_is_canonical(ASIdentifierChoice *choice)
 261 {
 262     ASN1_INTEGER *a_max_plus_one = NULL;
 263     BIGNUM *bn = NULL;
 264     int i, ret = 0;
 265
 266     /*
 267      * Empty element or inheritance is canonical.
 268      */
 269     if (choice == NULL || choice->type == ASIdentifierChoice_inherit)
 270         return 1;
 271
 272     /*
 273      * If not a list, or if empty list, it's broken.
 274      */
 275     if (choice->type != ASIdentifierChoice_asIdsOrRanges ||
 276         sk_ASIdOrRange_num(choice->u.asIdsOrRanges) == 0)
 277         return 0;
 278
 279     /*
 280      * It's a list, check it.
 281      */
 282     for (i = 0; i < sk_ASIdOrRange_num(choice->u.asIdsOrRanges) - 1; i++) {
 283         ASIdOrRange *a = sk_ASIdOrRange_value(choice->u.asIdsOrRanges, i);
 284         ASIdOrRange *b = sk_ASIdOrRange_value(choice->u.asIdsOrRanges, i + 1);
 285         ASN1_INTEGER *a_min = NULL, *a_max = NULL, *b_min = NULL, *b_max =
 286             NULL;
 287
 288         if (!extract_min_max(a, &a_min, &a_max)
 289                 || !extract_min_max(b, &b_min, &b_max))
 290             goto done;
 291
 292         /*
 293          * Punt misordered list, overlapping start, or inverted range.
 294          */
 295         if (ASN1_INTEGER_cmp(a_min, b_min) >= 0 ||
 296             ASN1_INTEGER_cmp(a_min, a_max) > 0 ||
 297             ASN1_INTEGER_cmp(b_min, b_max) > 0)
 298             goto done;
 299
 300         /*
 301          * Calculate a_max + 1 to check for adjacency.
 302          */
 303         if ((bn == NULL && (bn = BN_new()) == NULL) ||
 304             ASN1_INTEGER_to_BN(a_max, bn) == NULL ||
 305             !BN_add_word(bn, 1) ||
 306             (a_max_plus_one =
 307              BN_to_ASN1_INTEGER(bn, a_max_plus_one)) == NULL) {
 308             X509V3err(X509V3_F_ASIDENTIFIERCHOICE_IS_CANONICAL,
 309                       ERR_R_MALLOC_FAILURE);
 310             goto done;
 311         }
 312
 313         /*
 314          * Punt if adjacent or overlapping.
 315          */
 316         if (ASN1_INTEGER_cmp(a_max_plus_one, b_min) >= 0)
 317             goto done;
 318     }
 319
 320     /*
 321      * Check for inverted range.
 322      */
 323     i = sk_ASIdOrRange_num(choice->u.asIdsOrRanges) - 1;
 324     {
 325         ASIdOrRange *a = sk_ASIdOrRange_value(choice->u.asIdsOrRanges, i);
 326         ASN1_INTEGER *a_min, *a_max;
 327         if (a != NULL && a->type == ASIdOrRange_range) {
 328             if (!extract_min_max(a, &a_min, &a_max)
 329                     || ASN1_INTEGER_cmp(a_min, a_max) > 0)
 330                 goto done;
 331         }
 332     }
 333
 334     ret = 1;
 335
 336  done:
 337     ASN1_INTEGER_free(a_max_plus_one);
 338     BN_free(bn);
 339     return ret;
 340 }
 341
 342 /*
 343  * Check whether an ASIdentifier extension is in canonical form.
 344  */
 345 int X509v3_asid_is_canonical(ASIdentifiers *asid)
 346 {
 347     return (asid == NULL ||
 348             (ASIdentifierChoice_is_canonical(asid->asnum) &&
 349              ASIdentifierChoice_is_canonical(asid->rdi)));
 350 }
 351
 352 /*
 353  * Whack an ASIdentifierChoice into canonical form.
 354  */
 355 static int ASIdentifierChoice_canonize(ASIdentifierChoice *choice)
 356 {
 357     ASN1_INTEGER *a_max_plus_one = NULL;
 358     BIGNUM *bn = NULL;
 359     int i, ret = 0;
 360
 361     /*
 362      * Nothing to do for empty element or inheritance.
 363      */
 364     if (choice == NULL || choice->type == ASIdentifierChoice_inherit)
 365         return 1;
 366
 367     /*
 368      * If not a list, or if empty list, it's broken.
 369      */
 370     if (choice->type != ASIdentifierChoice_asIdsOrRanges ||
 371         sk_ASIdOrRange_num(choice->u.asIdsOrRanges) == 0) {
 372         X509V3err(X509V3_F_ASIDENTIFIERCHOICE_CANONIZE,
 373                   X509V3_R_EXTENSION_VALUE_ERROR);
 374         return 0;
 375     }
 376
 377     /*
 378      * We have a non-empty list.  Sort it.
 379      */
 380     sk_ASIdOrRange_sort(choice->u.asIdsOrRanges);
 381
 382     /*
 383      * Now check for errors and suboptimal encoding, rejecting the
 384      * former and fixing the latter.
 385      */
 386     for (i = 0; i < sk_ASIdOrRange_num(choice->u.asIdsOrRanges) - 1; i++) {
 387         ASIdOrRange *a = sk_ASIdOrRange_value(choice->u.asIdsOrRanges, i);
 388         ASIdOrRange *b = sk_ASIdOrRange_value(choice->u.asIdsOrRanges, i + 1);
 389         ASN1_INTEGER *a_min = NULL, *a_max = NULL, *b_min = NULL, *b_max =
 390             NULL;
 391
 392         if (!extract_min_max(a, &a_min, &a_max)
 393                 || !extract_min_max(b, &b_min, &b_max))
 394             goto done;
 395
 396         /*
 397          * Make sure we're properly sorted (paranoia).
 398          */
 399         if (!ossl_assert(ASN1_INTEGER_cmp(a_min, b_min) <= 0))
 400             goto done;
 401
 402         /*
 403          * Punt inverted ranges.
 404          */
 405         if (ASN1_INTEGER_cmp(a_min, a_max) > 0 ||
 406             ASN1_INTEGER_cmp(b_min, b_max) > 0)
 407             goto done;
 408
 409         /*
 410          * Check for overlaps.
 411          */
 412         if (ASN1_INTEGER_cmp(a_max, b_min) >= 0) {
 413             X509V3err(X509V3_F_ASIDENTIFIERCHOICE_CANONIZE,
 414                       X509V3_R_EXTENSION_VALUE_ERROR);
 415             goto done;
 416         }
 417
 418         /*
 419          * Calculate a_max + 1 to check for adjacency.
 420          */
 421         if ((bn == NULL && (bn = BN_new()) == NULL) ||
 422             ASN1_INTEGER_to_BN(a_max, bn) == NULL ||
 423             !BN_add_word(bn, 1) ||
 424             (a_max_plus_one =
 425              BN_to_ASN1_INTEGER(bn, a_max_plus_one)) == NULL) {
 426             X509V3err(X509V3_F_ASIDENTIFIERCHOICE_CANONIZE,
 427                       ERR_R_MALLOC_FAILURE);
 428             goto done;
 429         }
 430
 431         /*
 432          * If a and b are adjacent, merge them.
 433          */
 434         if (ASN1_INTEGER_cmp(a_max_plus_one, b_min) == 0) {
 435             ASRange *r;
 436             switch (a->type) {
 437             case ASIdOrRange_id:
 438                 if ((r = OPENSSL_malloc(sizeof(*r))) == NULL) {
 439                     X509V3err(X509V3_F_ASIDENTIFIERCHOICE_CANONIZE,
 440                               ERR_R_MALLOC_FAILURE);
 441                     goto done;
 442                 }
 443                 r->min = a_min;
 444                 r->max = b_max;
 445                 a->type = ASIdOrRange_range;
 446                 a->u.range = r;
 447                 break;
 448             case ASIdOrRange_range:
 449                 ASN1_INTEGER_free(a->u.range->max);
 450                 a->u.range->max = b_max;
 451                 break;
 452             }
 453             switch (b->type) {
 454             case ASIdOrRange_id:
 455                 b->u.id = NULL;
 456                 break;
 457             case ASIdOrRange_range:
 458                 b->u.range->max = NULL;
 459                 break;
 460             }
 461             ASIdOrRange_free(b);
 462             (void)sk_ASIdOrRange_delete(choice->u.asIdsOrRanges, i + 1);
 463             i--;
 464             continue;
 465         }
 466     }
 467
 468     /*
 469      * Check for final inverted range.
 470      */
 471     i = sk_ASIdOrRange_num(choice->u.asIdsOrRanges) - 1;
 472     {
 473         ASIdOrRange *a = sk_ASIdOrRange_value(choice->u.asIdsOrRanges, i);
 474         ASN1_INTEGER *a_min, *a_max;
 475         if (a != NULL && a->type == ASIdOrRange_range) {
 476             if (!extract_min_max(a, &a_min, &a_max)
 477                     || ASN1_INTEGER_cmp(a_min, a_max) > 0)
 478                 goto done;
 479         }
 480     }
 481
 482     /* Paranoia */
 483     if (!ossl_assert(ASIdentifierChoice_is_canonical(choice)))
 484         goto done;
 485
 486     ret = 1;
 487
 488  done:
 489     ASN1_INTEGER_free(a_max_plus_one);
 490     BN_free(bn);
 491     return ret;
 492 }
 493
 494 /*
 495  * Whack an ASIdentifier extension into canonical form.
 496  */
 497 int X509v3_asid_canonize(ASIdentifiers *asid)
 498 {
 499     return (asid == NULL ||
 500             (ASIdentifierChoice_canonize(asid->asnum) &&
 501              ASIdentifierChoice_canonize(asid->rdi)));
 502 }
 503
 504 /*
 505  * v2i method for an ASIdentifier extension.
 506  */
 507 static void *v2i_ASIdentifiers(const struct v3_ext_method *method,
 508                                struct v3_ext_ctx *ctx,
 509                                STACK_OF(CONF_VALUE) *values)
 510 {
 511     ASN1_INTEGER *min = NULL, *max = NULL;
 512     ASIdentifiers *asid = NULL;
 513     int i;
 514
 515     if ((asid = ASIdentifiers_new()) == NULL) {
 516         X509V3err(X509V3_F_V2I_ASIDENTIFIERS, ERR_R_MALLOC_FAILURE);
 517         return NULL;
 518     }
 519
 520     for (i = 0; i < sk_CONF_VALUE_num(values); i++) {
 521         CONF_VALUE *val = sk_CONF_VALUE_value(values, i);
 522         int i1 = 0, i2 = 0, i3 = 0, is_range = 0, which = 0;
 523
 524         /*
 525          * Figure out whether this is an AS or an RDI.
 526          */
 527         if (!name_cmp(val->name, "AS")) {
 528             which = V3_ASID_ASNUM;
 529         } else if (!name_cmp(val->name, "RDI")) {
 530             which = V3_ASID_RDI;
 531         } else {
 532             X509V3err(X509V3_F_V2I_ASIDENTIFIERS,
 533                       X509V3_R_EXTENSION_NAME_ERROR);
 534             X509V3_conf_err(val);
 535             goto err;
 536         }
 537
 538         /*
 539          * Handle inheritance.
 540          */
 541         if (strcmp(val->value, "inherit") == 0) {
 542             if (X509v3_asid_add_inherit(asid, which))
 543                 continue;
 544             X509V3err(X509V3_F_V2I_ASIDENTIFIERS,
 545                       X509V3_R_INVALID_INHERITANCE);
 546             X509V3_conf_err(val);
 547             goto err;
 548         }
 549
 550         /*
 551          * Number, range, or mistake, pick it apart and figure out which.
 552          */
 553         i1 = strspn(val->value, "0123456789");
 554         if (val->value[i1] == '\0') {
 555             is_range = 0;
 556         } else {
 557             is_range = 1;
 558             i2 = i1 + strspn(val->value + i1, " \t");
 559             if (val->value[i2] != '-') {
 560                 X509V3err(X509V3_F_V2I_ASIDENTIFIERS,
 561                           X509V3_R_INVALID_ASNUMBER);
 562                 X509V3_conf_err(val);
 563                 goto err;
 564             }
 565             i2++;
 566             i2 = i2 + strspn(val->value + i2, " \t");
 567             i3 = i2 + strspn(val->value + i2, "0123456789");
 568             if (val->value[i3] != '\0') {
 569                 X509V3err(X509V3_F_V2I_ASIDENTIFIERS,
 570                           X509V3_R_INVALID_ASRANGE);
 571                 X509V3_conf_err(val);
 572                 goto err;
 573             }
 574         }
 575
 576         /*
 577          * Syntax is ok, read and add it.
 578          */
 579         if (!is_range) {
 580             if (!X509V3_get_value_int(val, &min)) {
 581                 X509V3err(X509V3_F_V2I_ASIDENTIFIERS, ERR_R_MALLOC_FAILURE);
 582                 goto err;
 583             }
 584         } else {
 585             char *s = OPENSSL_strdup(val->value);
 586             if (s == NULL) {
 587                 X509V3err(X509V3_F_V2I_ASIDENTIFIERS, ERR_R_MALLOC_FAILURE);
 588                 goto err;
 589             }
 590             s[i1] = '\0';
 591             min = s2i_ASN1_INTEGER(NULL, s);
 592             max = s2i_ASN1_INTEGER(NULL, s + i2);
 593             OPENSSL_free(s);
 594             if (min == NULL || max == NULL) {
 595                 X509V3err(X509V3_F_V2I_ASIDENTIFIERS, ERR_R_MALLOC_FAILURE);
 596                 goto err;
 597             }
 598             if (ASN1_INTEGER_cmp(min, max) > 0) {
 599                 X509V3err(X509V3_F_V2I_ASIDENTIFIERS,
 600                           X509V3_R_EXTENSION_VALUE_ERROR);
 601                 goto err;
 602             }
 603         }
 604         if (!X509v3_asid_add_id_or_range(asid, which, min, max)) {
 605             X509V3err(X509V3_F_V2I_ASIDENTIFIERS, ERR_R_MALLOC_FAILURE);
 606             goto err;
 607         }
 608         min = max = NULL;
 609     }
 610
 611     /*
 612      * Canonize the result, then we're done.
 613      */
 614     if (!X509v3_asid_canonize(asid))
 615         goto err;
 616     return asid;
 617
 618  err:
 619     ASIdentifiers_free(asid);
 620     ASN1_INTEGER_free(min);
 621     ASN1_INTEGER_free(max);
 622     return NULL;
 623 }
 624
 625 /*
 626  * OpenSSL dispatch.
 627  */
 628 const X509V3_EXT_METHOD v3_asid = {
 629     NID_sbgp_autonomousSysNum,  /* nid */
 630     0,                          /* flags */
 631     ASN1_ITEM_ref(ASIdentifiers), /* template */
 632     0, 0, 0, 0,                 /* old functions, ignored */
 633     0,                          /* i2s */
 634     0,                          /* s2i */
 635     0,                          /* i2v */
 636     v2i_ASIdentifiers,          /* v2i */
 637     i2r_ASIdentifiers,          /* i2r */
 638     0,                          /* r2i */
 639     NULL                        /* extension-specific data */
 640 };
 641
 642 /*
 643  * Figure out whether extension uses inheritance.
 644  */
 645 int X509v3_asid_inherits(ASIdentifiers *asid)
 646 {
 647     return (asid != NULL &&
 648             ((asid->asnum != NULL &&
 649               asid->asnum->type == ASIdentifierChoice_inherit) ||
 650              (asid->rdi != NULL &&
 651               asid->rdi->type == ASIdentifierChoice_inherit)));
 652 }
 653
 654 /*
 655  * Figure out whether parent contains child.
 656  */
 657 static int asid_contains(ASIdOrRanges *parent, ASIdOrRanges *child)
 658 {
 659     ASN1_INTEGER *p_min = NULL, *p_max = NULL, *c_min = NULL, *c_max = NULL;
 660     int p, c;
 661
 662     if (child == NULL || parent == child)
 663         return 1;
 664     if (parent == NULL)
 665         return 0;
 666
 667     p = 0;
 668     for (c = 0; c < sk_ASIdOrRange_num(child); c++) {
 669         if (!extract_min_max(sk_ASIdOrRange_value(child, c), &c_min, &c_max))
 670             return 0;
 671         for (;; p++) {
 672             if (p >= sk_ASIdOrRange_num(parent))
 673                 return 0;
 674             extract_min_max(sk_ASIdOrRange_value(parent, p), &p_min, &p_max);
 675             if (ASN1_INTEGER_cmp(p_max, c_max) < 0)
 676                 continue;
 677             if (ASN1_INTEGER_cmp(p_min, c_min) > 0)
 678                 return 0;
 679             break;
 680         }
 681     }
 682
 683     return 1;
 684 }
 685
 686 /*
 687  * Test whether a is a subset of b.
 688  */
 689 int X509v3_asid_subset(ASIdentifiers *a, ASIdentifiers *b)
 690 {
 691     return (a == NULL ||
 692             a == b ||
 693             (b != NULL &&
 694              !X509v3_asid_inherits(a) &&
 695              !X509v3_asid_inherits(b) &&
 696              asid_contains(b->asnum->u.asIdsOrRanges,
 697                            a->asnum->u.asIdsOrRanges) &&
 698              asid_contains(b->rdi->u.asIdsOrRanges,
 699                            a->rdi->u.asIdsOrRanges)));
 700 }
 701
 702 /*
 703  * Validation error handling via callback.
 704  */
 705 #define validation_err(_err_)           \
 706   do {                                  \
 707     if (ctx != NULL) {                  \
 708       ctx->error = _err_;               \
 709       ctx->error_depth = i;             \
 710       ctx->current_cert = x;            \
 711       ret = ctx->verify_cb(0, ctx);     \
 712     } else {                            \
 713       ret = 0;                          \
 714     }                                   \
 715     if (!ret)                           \
 716       goto done;                        \
 717   } while (0)
 718
 719 /*
 720  * Core code for RFC 3779 3.3 path validation.
 721  */
 722 static int asid_validate_path_internal(X509_STORE_CTX *ctx,
 723                                        STACK_OF(X509) *chain,
 724                                        ASIdentifiers *ext)
 725 {
 726     ASIdOrRanges *child_as = NULL, *child_rdi = NULL;
 727     int i, ret = 1, inherit_as = 0, inherit_rdi = 0;
 728     X509 *x;
 729
 730     if (!ossl_assert(chain != NULL && sk_X509_num(chain) > 0)
 731             || !ossl_assert(ctx != NULL || ext != NULL)
 732             || !ossl_assert(ctx == NULL || ctx->verify_cb != NULL)) {
 733         if (ctx != NULL)
 734             ctx->error = X509_V_ERR_UNSPECIFIED;
 735         return 0;
 736     }
 737
 738
 739     /*
 740      * Figure out where to start.  If we don't have an extension to
 741      * check, we're done.  Otherwise, check canonical form and
 742      * set up for walking up the chain.
 743      */
 744     if (ext != NULL) {
 745         i = -1;
 746         x = NULL;
 747     } else {
 748         i = 0;
 749         x = sk_X509_value(chain, i);
 750         if (!ossl_assert(x != NULL)) {
 751             if (ctx != NULL)
 752                 ctx->error = X509_V_ERR_UNSPECIFIED;
 753             return 0;
 754         }
 755         if ((ext = x->rfc3779_asid) == NULL)
 756             goto done;
 757     }
 758     if (!X509v3_asid_is_canonical(ext))
 759         validation_err(X509_V_ERR_INVALID_EXTENSION);
 760     if (ext->asnum != NULL) {
 761         switch (ext->asnum->type) {
 762         case ASIdentifierChoice_inherit:
 763             inherit_as = 1;
 764             break;
 765         case ASIdentifierChoice_asIdsOrRanges:
 766             child_as = ext->asnum->u.asIdsOrRanges;
 767             break;
 768         }
 769     }
 770     if (ext->rdi != NULL) {
 771         switch (ext->rdi->type) {
 772         case ASIdentifierChoice_inherit:
 773             inherit_rdi = 1;
 774             break;
 775         case ASIdentifierChoice_asIdsOrRanges:
 776             child_rdi = ext->rdi->u.asIdsOrRanges;
 777             break;
 778         }
 779     }
 780
 781     /*
 782      * Now walk up the chain.  Extensions must be in canonical form, no
 783      * cert may list resources that its parent doesn't list.
 784      */
 785     for (i++; i < sk_X509_num(chain); i++) {
 786         x = sk_X509_value(chain, i);
 787         if (!ossl_assert(x != NULL)) {
 788             if (ctx != NULL)
 789                 ctx->error = X509_V_ERR_UNSPECIFIED;
 790             return 0;
 791         }
 792         if (x->rfc3779_asid == NULL) {
 793             if (child_as != NULL || child_rdi != NULL)
 794                 validation_err(X509_V_ERR_UNNESTED_RESOURCE);
 795             continue;
 796         }
 797         if (!X509v3_asid_is_canonical(x->rfc3779_asid))
 798             validation_err(X509_V_ERR_INVALID_EXTENSION);
 799         if (x->rfc3779_asid->asnum == NULL && child_as != NULL) {
 800             validation_err(X509_V_ERR_UNNESTED_RESOURCE);
 801             child_as = NULL;
 802             inherit_as = 0;
 803         }
 804         if (x->rfc3779_asid->asnum != NULL &&
 805             x->rfc3779_asid->asnum->type ==
 806             ASIdentifierChoice_asIdsOrRanges) {
 807             if (inherit_as
 808                 || asid_contains(x->rfc3779_asid->asnum->u.asIdsOrRanges,
 809                                  child_as)) {
 810                 child_as = x->rfc3779_asid->asnum->u.asIdsOrRanges;
 811                 inherit_as = 0;
 812             } else {
 813                 validation_err(X509_V_ERR_UNNESTED_RESOURCE);
 814             }
 815         }
 816         if (x->rfc3779_asid->rdi == NULL && child_rdi != NULL) {
 817             validation_err(X509_V_ERR_UNNESTED_RESOURCE);
 818             child_rdi = NULL;
 819             inherit_rdi = 0;
 820         }
 821         if (x->rfc3779_asid->rdi != NULL &&
 822             x->rfc3779_asid->rdi->type == ASIdentifierChoice_asIdsOrRanges) {
 823             if (inherit_rdi ||
 824                 asid_contains(x->rfc3779_asid->rdi->u.asIdsOrRanges,
 825                               child_rdi)) {
 826                 child_rdi = x->rfc3779_asid->rdi->u.asIdsOrRanges;
 827                 inherit_rdi = 0;
 828             } else {
 829                 validation_err(X509_V_ERR_UNNESTED_RESOURCE);
 830             }
 831         }
 832     }
 833
 834     /*
 835      * Trust anchor can't inherit.
 836      */
 837     if (!ossl_assert(x != NULL)) {
 838         if (ctx != NULL)
 839             ctx->error = X509_V_ERR_UNSPECIFIED;
 840         return 0;
 841     }
 842     if (x->rfc3779_asid != NULL) {
 843         if (x->rfc3779_asid->asnum != NULL &&
 844             x->rfc3779_asid->asnum->type == ASIdentifierChoice_inherit)
 845             validation_err(X509_V_ERR_UNNESTED_RESOURCE);
 846         if (x->rfc3779_asid->rdi != NULL &&
 847             x->rfc3779_asid->rdi->type == ASIdentifierChoice_inherit)
 848             validation_err(X509_V_ERR_UNNESTED_RESOURCE);
 849     }
 850
 851  done:
 852     return ret;
 853 }
 854
 855 #undef validation_err
 856
 857 /*
 858  * RFC 3779 3.3 path validation -- called from X509_verify_cert().
 859  */
 860 int X509v3_asid_validate_path(X509_STORE_CTX *ctx)
 861 {
 862     if (ctx->chain == NULL
 863             || sk_X509_num(ctx->chain) == 0
 864             || ctx->verify_cb == NULL)
 865         return 0;
 866     return asid_validate_path_internal(ctx, ctx->chain, NULL);
 867 }
 868
 869 /*
 870  * RFC 3779 3.3 path validation of an extension.
 871  * Test whether chain covers extension.
 872  */
 873 int X509v3_asid_validate_resource_set(STACK_OF(X509) *chain,
 874                                       ASIdentifiers *ext, int allow_inheritance)
 875 {
 876     if (ext == NULL)
 877         return 1;
 878     if (chain == NULL || sk_X509_num(chain) == 0)
 879         return 0;
 880     if (!allow_inheritance && X509v3_asid_inherits(ext))
 881         return 0;
 882     return asid_validate_path_internal(NULL, chain, ext);
 883 }
 884
 885 #endif                          /* OPENSSL_NO_RFC3779 */