crypto/x509/v3_asid.c

   1 /*
   2  * Copyright 2006-2020 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 /*
  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 "crypto/x509.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 DEFINE_STACK_OF(ASIdOrRange)
  59 DEFINE_STACK_OF(CONF_VALUE)
  60 DEFINE_STACK_OF(X509)
  61
  62 /*
  63  * i2r method for an ASIdentifierChoice.
  64  */
  65 static int i2r_ASIdentifierChoice(BIO *out,
  66                                   ASIdentifierChoice *choice,
  67                                   int indent, const char *msg)
  68 {
  69     int i;
  70     char *s;
  71     if (choice == NULL)
  72         return 1;
  73     BIO_printf(out, "%*s%s:\n", indent, "", msg);
  74     switch (choice->type) {
  75     case ASIdentifierChoice_inherit:
  76         BIO_printf(out, "%*sinherit\n", indent + 2, "");
  77         break;
  78     case ASIdentifierChoice_asIdsOrRanges:
  79         for (i = 0; i < sk_ASIdOrRange_num(choice->u.asIdsOrRanges); i++) {
  80             ASIdOrRange *aor =
  81                 sk_ASIdOrRange_value(choice->u.asIdsOrRanges, i);
  82             switch (aor->type) {
  83             case ASIdOrRange_id:
  84                 if ((s = i2s_ASN1_INTEGER(NULL, aor->u.id)) == NULL)
  85                     return 0;
  86                 BIO_printf(out, "%*s%s\n", indent + 2, "", s);
  87                 OPENSSL_free(s);
  88                 break;
  89             case ASIdOrRange_range:
  90                 if ((s = i2s_ASN1_INTEGER(NULL, aor->u.range->min)) == NULL)
  91                     return 0;
  92                 BIO_printf(out, "%*s%s-", indent + 2, "", s);
  93                 OPENSSL_free(s);
  94                 if ((s = i2s_ASN1_INTEGER(NULL, aor->u.range->max)) == NULL)
  95                     return 0;
  96                 BIO_printf(out, "%s\n", s);
  97                 OPENSSL_free(s);
  98                 break;
  99             default:
 100                 return 0;
 101             }
 102         }
 103         break;
 104     default:
 105         return 0;
 106     }
 107     return 1;
 108 }
 109
 110 /*
 111  * i2r method for an ASIdentifier extension.
 112  */
 113 static int i2r_ASIdentifiers(const X509V3_EXT_METHOD *method,
 114                              void *ext, BIO *out, int indent)
 115 {
 116     ASIdentifiers *asid = ext;
 117     return (i2r_ASIdentifierChoice(out, asid->asnum, indent,
 118                                    "Autonomous System Numbers") &&
 119             i2r_ASIdentifierChoice(out, asid->rdi, indent,
 120                                    "Routing Domain Identifiers"));
 121 }
 122
 123 /*
 124  * Sort comparison function for a sequence of ASIdOrRange elements.
 125  */
 126 static int ASIdOrRange_cmp(const ASIdOrRange *const *a_,
 127                            const ASIdOrRange *const *b_)
 128 {
 129     const ASIdOrRange *a = *a_, *b = *b_;
 130
 131     assert((a->type == ASIdOrRange_id && a->u.id != NULL) ||
 132            (a->type == ASIdOrRange_range && a->u.range != NULL &&
 133             a->u.range->min != NULL && a->u.range->max != NULL));
 134
 135     assert((b->type == ASIdOrRange_id && b->u.id != NULL) ||
 136            (b->type == ASIdOrRange_range && b->u.range != NULL &&
 137             b->u.range->min != NULL && b->u.range->max != NULL));
 138
 139     if (a->type == ASIdOrRange_id && b->type == ASIdOrRange_id)
 140         return ASN1_INTEGER_cmp(a->u.id, b->u.id);
 141
 142     if (a->type == ASIdOrRange_range && b->type == ASIdOrRange_range) {
 143         int r = ASN1_INTEGER_cmp(a->u.range->min, b->u.range->min);
 144         return r != 0 ? r : ASN1_INTEGER_cmp(a->u.range->max,
 145                                              b->u.range->max);
 146     }
 147
 148     if (a->type == ASIdOrRange_id)
 149         return ASN1_INTEGER_cmp(a->u.id, b->u.range->min);
 150     else
 151         return ASN1_INTEGER_cmp(a->u.range->min, b->u.id);
 152 }
 153
 154 /*
 155  * Add an inherit element.
 156  */
 157 int X509v3_asid_add_inherit(ASIdentifiers *asid, int which)
 158 {
 159     ASIdentifierChoice **choice;
 160     if (asid == NULL)
 161         return 0;
 162     switch (which) {
 163     case V3_ASID_ASNUM:
 164         choice = &asid->asnum;
 165         break;
 166     case V3_ASID_RDI:
 167         choice = &asid->rdi;
 168         break;
 169     default:
 170         return 0;
 171     }
 172     if (*choice == NULL) {
 173         if ((*choice = ASIdentifierChoice_new()) == NULL)
 174             return 0;
 175         if (((*choice)->u.inherit = ASN1_NULL_new()) == NULL)
 176             return 0;
 177         (*choice)->type = ASIdentifierChoice_inherit;
 178     }
 179     return (*choice)->type == ASIdentifierChoice_inherit;
 180 }
 181
 182 /*
 183  * Add an ID or range to an ASIdentifierChoice.
 184  */
 185 int X509v3_asid_add_id_or_range(ASIdentifiers *asid,
 186                                 int which, ASN1_INTEGER *min, ASN1_INTEGER *max)
 187 {
 188     ASIdentifierChoice **choice;
 189     ASIdOrRange *aor;
 190     if (asid == NULL)
 191         return 0;
 192     switch (which) {
 193     case V3_ASID_ASNUM:
 194         choice = &asid->asnum;
 195         break;
 196     case V3_ASID_RDI:
 197         choice = &asid->rdi;
 198         break;
 199     default:
 200         return 0;
 201     }
 202     if (*choice != NULL && (*choice)->type == ASIdentifierChoice_inherit)
 203         return 0;
 204     if (*choice == NULL) {
 205         if ((*choice = ASIdentifierChoice_new()) == 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))
 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     ASN1_INTEGER *orig;
 264     BIGNUM *bn = NULL;
 265     int i, ret = 0;
 266
 267     /*
 268      * Empty element or inheritance is canonical.
 269      */
 270     if (choice == NULL || choice->type == ASIdentifierChoice_inherit)
 271         return 1;
 272
 273     /*
 274      * If not a list, or if empty list, it's broken.
 275      */
 276     if (choice->type != ASIdentifierChoice_asIdsOrRanges ||
 277         sk_ASIdOrRange_num(choice->u.asIdsOrRanges) == 0)
 278         return 0;
 279
 280     /*
 281      * It's a list, check it.
 282      */
 283     for (i = 0; i < sk_ASIdOrRange_num(choice->u.asIdsOrRanges) - 1; i++) {
 284         ASIdOrRange *a = sk_ASIdOrRange_value(choice->u.asIdsOrRanges, i);
 285         ASIdOrRange *b = sk_ASIdOrRange_value(choice->u.asIdsOrRanges, i + 1);
 286         ASN1_INTEGER *a_min = NULL, *a_max = NULL, *b_min = NULL, *b_max =
 287             NULL;
 288
 289         if (!extract_min_max(a, &a_min, &a_max)
 290                 || !extract_min_max(b, &b_min, &b_max))
 291             goto done;
 292
 293         /*
 294          * Punt misordered list, overlapping start, or inverted range.
 295          */
 296         if (ASN1_INTEGER_cmp(a_min, b_min) >= 0 ||
 297             ASN1_INTEGER_cmp(a_min, a_max) > 0 ||
 298             ASN1_INTEGER_cmp(b_min, b_max) > 0)
 299             goto done;
 300
 301         /*
 302          * Calculate a_max + 1 to check for adjacency.
 303          */
 304         if ((bn == NULL && (bn = BN_new()) == NULL) ||
 305             ASN1_INTEGER_to_BN(a_max, bn) == NULL ||
 306             !BN_add_word(bn, 1)) {
 307             X509V3err(X509V3_F_ASIDENTIFIERCHOICE_IS_CANONICAL,
 308                       ERR_R_MALLOC_FAILURE);
 309             goto done;
 310         }
 311
 312         if ((a_max_plus_one =
 313                 BN_to_ASN1_INTEGER(bn, orig = a_max_plus_one)) == NULL) {
 314             a_max_plus_one = orig;
 315             X509V3err(X509V3_F_ASIDENTIFIERCHOICE_IS_CANONICAL,
 316                       ERR_R_MALLOC_FAILURE);
 317             goto done;
 318         }
 319
 320         /*
 321          * Punt if adjacent or overlapping.
 322          */
 323         if (ASN1_INTEGER_cmp(a_max_plus_one, b_min) >= 0)
 324             goto done;
 325     }
 326
 327     /*
 328      * Check for inverted range.
 329      */
 330     i = sk_ASIdOrRange_num(choice->u.asIdsOrRanges) - 1;
 331     {
 332         ASIdOrRange *a = sk_ASIdOrRange_value(choice->u.asIdsOrRanges, i);
 333         ASN1_INTEGER *a_min, *a_max;
 334         if (a != NULL && a->type == ASIdOrRange_range) {
 335             if (!extract_min_max(a, &a_min, &a_max)
 336                     || ASN1_INTEGER_cmp(a_min, a_max) > 0)
 337                 goto done;
 338         }
 339     }
 340
 341     ret = 1;
 342
 343  done:
 344     ASN1_INTEGER_free(a_max_plus_one);
 345     BN_free(bn);
 346     return ret;
 347 }
 348
 349 /*
 350  * Check whether an ASIdentifier extension is in canonical form.
 351  */
 352 int X509v3_asid_is_canonical(ASIdentifiers *asid)
 353 {
 354     return (asid == NULL ||
 355             (ASIdentifierChoice_is_canonical(asid->asnum) &&
 356              ASIdentifierChoice_is_canonical(asid->rdi)));
 357 }
 358
 359 /*
 360  * Whack an ASIdentifierChoice into canonical form.
 361  */
 362 static int ASIdentifierChoice_canonize(ASIdentifierChoice *choice)
 363 {
 364     ASN1_INTEGER *a_max_plus_one = NULL;
 365     ASN1_INTEGER *orig;
 366     BIGNUM *bn = NULL;
 367     int i, ret = 0;
 368
 369     /*
 370      * Nothing to do for empty element or inheritance.
 371      */
 372     if (choice == NULL || choice->type == ASIdentifierChoice_inherit)
 373         return 1;
 374
 375     /*
 376      * If not a list, or if empty list, it's broken.
 377      */
 378     if (choice->type != ASIdentifierChoice_asIdsOrRanges ||
 379         sk_ASIdOrRange_num(choice->u.asIdsOrRanges) == 0) {
 380         X509V3err(X509V3_F_ASIDENTIFIERCHOICE_CANONIZE,
 381                   X509V3_R_EXTENSION_VALUE_ERROR);
 382         return 0;
 383     }
 384
 385     /*
 386      * We have a non-empty list.  Sort it.
 387      */
 388     sk_ASIdOrRange_sort(choice->u.asIdsOrRanges);
 389
 390     /*
 391      * Now check for errors and suboptimal encoding, rejecting the
 392      * former and fixing the latter.
 393      */
 394     for (i = 0; i < sk_ASIdOrRange_num(choice->u.asIdsOrRanges) - 1; i++) {
 395         ASIdOrRange *a = sk_ASIdOrRange_value(choice->u.asIdsOrRanges, i);
 396         ASIdOrRange *b = sk_ASIdOrRange_value(choice->u.asIdsOrRanges, i + 1);
 397         ASN1_INTEGER *a_min = NULL, *a_max = NULL, *b_min = NULL, *b_max =
 398             NULL;
 399
 400         if (!extract_min_max(a, &a_min, &a_max)
 401                 || !extract_min_max(b, &b_min, &b_max))
 402             goto done;
 403
 404         /*
 405          * Make sure we're properly sorted (paranoia).
 406          */
 407         if (!ossl_assert(ASN1_INTEGER_cmp(a_min, b_min) <= 0))
 408             goto done;
 409
 410         /*
 411          * Punt inverted ranges.
 412          */
 413         if (ASN1_INTEGER_cmp(a_min, a_max) > 0 ||
 414             ASN1_INTEGER_cmp(b_min, b_max) > 0)
 415             goto done;
 416
 417         /*
 418          * Check for overlaps.
 419          */
 420         if (ASN1_INTEGER_cmp(a_max, b_min) >= 0) {
 421             X509V3err(X509V3_F_ASIDENTIFIERCHOICE_CANONIZE,
 422                       X509V3_R_EXTENSION_VALUE_ERROR);
 423             goto done;
 424         }
 425
 426         /*
 427          * Calculate a_max + 1 to check for adjacency.
 428          */
 429         if ((bn == NULL && (bn = BN_new()) == NULL) ||
 430             ASN1_INTEGER_to_BN(a_max, bn) == NULL ||
 431             !BN_add_word(bn, 1)) {
 432             X509V3err(X509V3_F_ASIDENTIFIERCHOICE_CANONIZE,
 433                       ERR_R_MALLOC_FAILURE);
 434             goto done;
 435         }
 436
 437         if ((a_max_plus_one =
 438                  BN_to_ASN1_INTEGER(bn, orig = a_max_plus_one)) == NULL) {
 439             a_max_plus_one = orig;
 440             X509V3err(X509V3_F_ASIDENTIFIERCHOICE_CANONIZE,
 441                       ERR_R_MALLOC_FAILURE);
 442             goto done;
 443         }
 444
 445         /*
 446          * If a and b are adjacent, merge them.
 447          */
 448         if (ASN1_INTEGER_cmp(a_max_plus_one, b_min) == 0) {
 449             ASRange *r;
 450             switch (a->type) {
 451             case ASIdOrRange_id:
 452                 if ((r = OPENSSL_malloc(sizeof(*r))) == NULL) {
 453                     X509V3err(X509V3_F_ASIDENTIFIERCHOICE_CANONIZE,
 454                               ERR_R_MALLOC_FAILURE);
 455                     goto done;
 456                 }
 457                 r->min = a_min;
 458                 r->max = b_max;
 459                 a->type = ASIdOrRange_range;
 460                 a->u.range = r;
 461                 break;
 462             case ASIdOrRange_range:
 463                 ASN1_INTEGER_free(a->u.range->max);
 464                 a->u.range->max = b_max;
 465                 break;
 466             }
 467             switch (b->type) {
 468             case ASIdOrRange_id:
 469                 b->u.id = NULL;
 470                 break;
 471             case ASIdOrRange_range:
 472                 b->u.range->max = NULL;
 473                 break;
 474             }
 475             ASIdOrRange_free(b);
 476             (void)sk_ASIdOrRange_delete(choice->u.asIdsOrRanges, i + 1);
 477             i--;
 478             continue;
 479         }
 480     }
 481
 482     /*
 483      * Check for final inverted range.
 484      */
 485     i = sk_ASIdOrRange_num(choice->u.asIdsOrRanges) - 1;
 486     {
 487         ASIdOrRange *a = sk_ASIdOrRange_value(choice->u.asIdsOrRanges, i);
 488         ASN1_INTEGER *a_min, *a_max;
 489         if (a != NULL && a->type == ASIdOrRange_range) {
 490             if (!extract_min_max(a, &a_min, &a_max)
 491                     || ASN1_INTEGER_cmp(a_min, a_max) > 0)
 492                 goto done;
 493         }
 494     }
 495
 496     /* Paranoia */
 497     if (!ossl_assert(ASIdentifierChoice_is_canonical(choice)))
 498         goto done;
 499
 500     ret = 1;
 501
 502  done:
 503     ASN1_INTEGER_free(a_max_plus_one);
 504     BN_free(bn);
 505     return ret;
 506 }
 507
 508 /*
 509  * Whack an ASIdentifier extension into canonical form.
 510  */
 511 int X509v3_asid_canonize(ASIdentifiers *asid)
 512 {
 513     return (asid == NULL ||
 514             (ASIdentifierChoice_canonize(asid->asnum) &&
 515              ASIdentifierChoice_canonize(asid->rdi)));
 516 }
 517
 518 /*
 519  * v2i method for an ASIdentifier extension.
 520  */
 521 static void *v2i_ASIdentifiers(const struct v3_ext_method *method,
 522                                struct v3_ext_ctx *ctx,
 523                                STACK_OF(CONF_VALUE) *values)
 524 {
 525     ASN1_INTEGER *min = NULL, *max = NULL;
 526     ASIdentifiers *asid = NULL;
 527     int i;
 528
 529     if ((asid = ASIdentifiers_new()) == NULL) {
 530         X509V3err(X509V3_F_V2I_ASIDENTIFIERS, ERR_R_MALLOC_FAILURE);
 531         return NULL;
 532     }
 533
 534     for (i = 0; i < sk_CONF_VALUE_num(values); i++) {
 535         CONF_VALUE *val = sk_CONF_VALUE_value(values, i);
 536         int i1 = 0, i2 = 0, i3 = 0, is_range = 0, which = 0;
 537
 538         /*
 539          * Figure out whether this is an AS or an RDI.
 540          */
 541         if (!v3_name_cmp(val->name, "AS")) {
 542             which = V3_ASID_ASNUM;
 543         } else if (!v3_name_cmp(val->name, "RDI")) {
 544             which = V3_ASID_RDI;
 545         } else {
 546             X509V3err(X509V3_F_V2I_ASIDENTIFIERS,
 547                       X509V3_R_EXTENSION_NAME_ERROR);
 548             X509V3_conf_err(val);
 549             goto err;
 550         }
 551
 552         /*
 553          * Handle inheritance.
 554          */
 555         if (strcmp(val->value, "inherit") == 0) {
 556             if (X509v3_asid_add_inherit(asid, which))
 557                 continue;
 558             X509V3err(X509V3_F_V2I_ASIDENTIFIERS,
 559                       X509V3_R_INVALID_INHERITANCE);
 560             X509V3_conf_err(val);
 561             goto err;
 562         }
 563
 564         /*
 565          * Number, range, or mistake, pick it apart and figure out which.
 566          */
 567         i1 = strspn(val->value, "0123456789");
 568         if (val->value[i1] == '\0') {
 569             is_range = 0;
 570         } else {
 571             is_range = 1;
 572             i2 = i1 + strspn(val->value + i1, " \t");
 573             if (val->value[i2] != '-') {
 574                 X509V3err(X509V3_F_V2I_ASIDENTIFIERS,
 575                           X509V3_R_INVALID_ASNUMBER);
 576                 X509V3_conf_err(val);
 577                 goto err;
 578             }
 579             i2++;
 580             i2 = i2 + strspn(val->value + i2, " \t");
 581             i3 = i2 + strspn(val->value + i2, "0123456789");
 582             if (val->value[i3] != '\0') {
 583                 X509V3err(X509V3_F_V2I_ASIDENTIFIERS,
 584                           X509V3_R_INVALID_ASRANGE);
 585                 X509V3_conf_err(val);
 586                 goto err;
 587             }
 588         }
 589
 590         /*
 591          * Syntax is ok, read and add it.
 592          */
 593         if (!is_range) {
 594             if (!X509V3_get_value_int(val, &min)) {
 595                 X509V3err(X509V3_F_V2I_ASIDENTIFIERS, ERR_R_MALLOC_FAILURE);
 596                 goto err;
 597             }
 598         } else {
 599             char *s = OPENSSL_strdup(val->value);
 600             if (s == NULL) {
 601                 X509V3err(X509V3_F_V2I_ASIDENTIFIERS, ERR_R_MALLOC_FAILURE);
 602                 goto err;
 603             }
 604             s[i1] = '\0';
 605             min = s2i_ASN1_INTEGER(NULL, s);
 606             max = s2i_ASN1_INTEGER(NULL, s + i2);
 607             OPENSSL_free(s);
 608             if (min == NULL || max == NULL) {
 609                 X509V3err(X509V3_F_V2I_ASIDENTIFIERS, ERR_R_MALLOC_FAILURE);
 610                 goto err;
 611             }
 612             if (ASN1_INTEGER_cmp(min, max) > 0) {
 613                 X509V3err(X509V3_F_V2I_ASIDENTIFIERS,
 614                           X509V3_R_EXTENSION_VALUE_ERROR);
 615                 goto err;
 616             }
 617         }
 618         if (!X509v3_asid_add_id_or_range(asid, which, min, max)) {
 619             X509V3err(X509V3_F_V2I_ASIDENTIFIERS, ERR_R_MALLOC_FAILURE);
 620             goto err;
 621         }
 622         min = max = NULL;
 623     }
 624
 625     /*
 626      * Canonize the result, then we're done.
 627      */
 628     if (!X509v3_asid_canonize(asid))
 629         goto err;
 630     return asid;
 631
 632  err:
 633     ASIdentifiers_free(asid);
 634     ASN1_INTEGER_free(min);
 635     ASN1_INTEGER_free(max);
 636     return NULL;
 637 }
 638
 639 /*
 640  * OpenSSL dispatch.
 641  */
 642 const X509V3_EXT_METHOD v3_asid = {
 643     NID_sbgp_autonomousSysNum,  /* nid */
 644     0,                          /* flags */
 645     ASN1_ITEM_ref(ASIdentifiers), /* template */
 646     0, 0, 0, 0,                 /* old functions, ignored */
 647     0,                          /* i2s */
 648     0,                          /* s2i */
 649     0,                          /* i2v */
 650     v2i_ASIdentifiers,          /* v2i */
 651     i2r_ASIdentifiers,          /* i2r */
 652     0,                          /* r2i */
 653     NULL                        /* extension-specific data */
 654 };
 655
 656 /*
 657  * Figure out whether extension uses inheritance.
 658  */
 659 int X509v3_asid_inherits(ASIdentifiers *asid)
 660 {
 661     return (asid != NULL &&
 662             ((asid->asnum != NULL &&
 663               asid->asnum->type == ASIdentifierChoice_inherit) ||
 664              (asid->rdi != NULL &&
 665               asid->rdi->type == ASIdentifierChoice_inherit)));
 666 }
 667
 668 /*
 669  * Figure out whether parent contains child.
 670  */
 671 static int asid_contains(ASIdOrRanges *parent, ASIdOrRanges *child)
 672 {
 673     ASN1_INTEGER *p_min = NULL, *p_max = NULL, *c_min = NULL, *c_max = NULL;
 674     int p, c;
 675
 676     if (child == NULL || parent == child)
 677         return 1;
 678     if (parent == NULL)
 679         return 0;
 680
 681     p = 0;
 682     for (c = 0; c < sk_ASIdOrRange_num(child); c++) {
 683         if (!extract_min_max(sk_ASIdOrRange_value(child, c), &c_min, &c_max))
 684             return 0;
 685         for (;; p++) {
 686             if (p >= sk_ASIdOrRange_num(parent))
 687                 return 0;
 688             if (!extract_min_max(sk_ASIdOrRange_value(parent, p), &p_min,
 689                                  &p_max))
 690                 return 0;
 691             if (ASN1_INTEGER_cmp(p_max, c_max) < 0)
 692                 continue;
 693             if (ASN1_INTEGER_cmp(p_min, c_min) > 0)
 694                 return 0;
 695             break;
 696         }
 697     }
 698
 699     return 1;
 700 }
 701
 702 /*
 703  * Test whether a is a subset of b.
 704  */
 705 int X509v3_asid_subset(ASIdentifiers *a, ASIdentifiers *b)
 706 {
 707     return (a == NULL ||
 708             a == b ||
 709             (b != NULL &&
 710              !X509v3_asid_inherits(a) &&
 711              !X509v3_asid_inherits(b) &&
 712              asid_contains(b->asnum->u.asIdsOrRanges,
 713                            a->asnum->u.asIdsOrRanges) &&
 714              asid_contains(b->rdi->u.asIdsOrRanges,
 715                            a->rdi->u.asIdsOrRanges)));
 716 }
 717
 718 /*
 719  * Validation error handling via callback.
 720  */
 721 #define validation_err(_err_)           \
 722   do {                                  \
 723     if (ctx != NULL) {                  \
 724       ctx->error = _err_;               \
 725       ctx->error_depth = i;             \
 726       ctx->current_cert = x;            \
 727       ret = ctx->verify_cb(0, ctx);     \
 728     } else {                            \
 729       ret = 0;                          \
 730     }                                   \
 731     if (!ret)                           \
 732       goto done;                        \
 733   } while (0)
 734
 735 /*
 736  * Core code for RFC 3779 3.3 path validation.
 737  */
 738 static int asid_validate_path_internal(X509_STORE_CTX *ctx,
 739                                        STACK_OF(X509) *chain,
 740                                        ASIdentifiers *ext)
 741 {
 742     ASIdOrRanges *child_as = NULL, *child_rdi = NULL;
 743     int i, ret = 1, inherit_as = 0, inherit_rdi = 0;
 744     X509 *x;
 745
 746     if (!ossl_assert(chain != NULL && sk_X509_num(chain) > 0)
 747             || !ossl_assert(ctx != NULL || ext != NULL)
 748             || !ossl_assert(ctx == NULL || ctx->verify_cb != NULL)) {
 749         if (ctx != NULL)
 750             ctx->error = X509_V_ERR_UNSPECIFIED;
 751         return 0;
 752     }
 753
 754
 755     /*
 756      * Figure out where to start.  If we don't have an extension to
 757      * check, we're done.  Otherwise, check canonical form and
 758      * set up for walking up the chain.
 759      */
 760     if (ext != NULL) {
 761         i = -1;
 762         x = NULL;
 763     } else {
 764         i = 0;
 765         x = sk_X509_value(chain, i);
 766         if ((ext = x->rfc3779_asid) == NULL)
 767             goto done;
 768     }
 769     if (!X509v3_asid_is_canonical(ext))
 770         validation_err(X509_V_ERR_INVALID_EXTENSION);
 771     if (ext->asnum != NULL) {
 772         switch (ext->asnum->type) {
 773         case ASIdentifierChoice_inherit:
 774             inherit_as = 1;
 775             break;
 776         case ASIdentifierChoice_asIdsOrRanges:
 777             child_as = ext->asnum->u.asIdsOrRanges;
 778             break;
 779         }
 780     }
 781     if (ext->rdi != NULL) {
 782         switch (ext->rdi->type) {
 783         case ASIdentifierChoice_inherit:
 784             inherit_rdi = 1;
 785             break;
 786         case ASIdentifierChoice_asIdsOrRanges:
 787             child_rdi = ext->rdi->u.asIdsOrRanges;
 788             break;
 789         }
 790     }
 791
 792     /*
 793      * Now walk up the chain.  Extensions must be in canonical form, no
 794      * cert may list resources that its parent doesn't list.
 795      */
 796     for (i++; i < sk_X509_num(chain); i++) {
 797         x = sk_X509_value(chain, i);
 798         if (!ossl_assert(x != NULL)) {
 799             if (ctx != NULL)
 800                 ctx->error = X509_V_ERR_UNSPECIFIED;
 801             return 0;
 802         }
 803         if (x->rfc3779_asid == NULL) {
 804             if (child_as != NULL || child_rdi != NULL)
 805                 validation_err(X509_V_ERR_UNNESTED_RESOURCE);
 806             continue;
 807         }
 808         if (!X509v3_asid_is_canonical(x->rfc3779_asid))
 809             validation_err(X509_V_ERR_INVALID_EXTENSION);
 810         if (x->rfc3779_asid->asnum == NULL && child_as != NULL) {
 811             validation_err(X509_V_ERR_UNNESTED_RESOURCE);
 812             child_as = NULL;
 813             inherit_as = 0;
 814         }
 815         if (x->rfc3779_asid->asnum != NULL &&
 816             x->rfc3779_asid->asnum->type ==
 817             ASIdentifierChoice_asIdsOrRanges) {
 818             if (inherit_as
 819                 || asid_contains(x->rfc3779_asid->asnum->u.asIdsOrRanges,
 820                                  child_as)) {
 821                 child_as = x->rfc3779_asid->asnum->u.asIdsOrRanges;
 822                 inherit_as = 0;
 823             } else {
 824                 validation_err(X509_V_ERR_UNNESTED_RESOURCE);
 825             }
 826         }
 827         if (x->rfc3779_asid->rdi == NULL && child_rdi != NULL) {
 828             validation_err(X509_V_ERR_UNNESTED_RESOURCE);
 829             child_rdi = NULL;
 830             inherit_rdi = 0;
 831         }
 832         if (x->rfc3779_asid->rdi != NULL &&
 833             x->rfc3779_asid->rdi->type == ASIdentifierChoice_asIdsOrRanges) {
 834             if (inherit_rdi ||
 835                 asid_contains(x->rfc3779_asid->rdi->u.asIdsOrRanges,
 836                               child_rdi)) {
 837                 child_rdi = x->rfc3779_asid->rdi->u.asIdsOrRanges;
 838                 inherit_rdi = 0;
 839             } else {
 840                 validation_err(X509_V_ERR_UNNESTED_RESOURCE);
 841             }
 842         }
 843     }
 844
 845     /*
 846      * Trust anchor can't inherit.
 847      */
 848     if (!ossl_assert(x != NULL)) {
 849         if (ctx != NULL)
 850             ctx->error = X509_V_ERR_UNSPECIFIED;
 851         return 0;
 852     }
 853     if (x->rfc3779_asid != NULL) {
 854         if (x->rfc3779_asid->asnum != NULL &&
 855             x->rfc3779_asid->asnum->type == ASIdentifierChoice_inherit)
 856             validation_err(X509_V_ERR_UNNESTED_RESOURCE);
 857         if (x->rfc3779_asid->rdi != NULL &&
 858             x->rfc3779_asid->rdi->type == ASIdentifierChoice_inherit)
 859             validation_err(X509_V_ERR_UNNESTED_RESOURCE);
 860     }
 861
 862  done:
 863     return ret;
 864 }
 865
 866 #undef validation_err
 867
 868 /*
 869  * RFC 3779 3.3 path validation -- called from X509_verify_cert().
 870  */
 871 int X509v3_asid_validate_path(X509_STORE_CTX *ctx)
 872 {
 873     if (ctx->chain == NULL
 874             || sk_X509_num(ctx->chain) == 0
 875             || ctx->verify_cb == NULL) {
 876         ctx->error = X509_V_ERR_UNSPECIFIED;
 877         return 0;
 878     }
 879     return asid_validate_path_internal(ctx, ctx->chain, NULL);
 880 }
 881
 882 /*
 883  * RFC 3779 3.3 path validation of an extension.
 884  * Test whether chain covers extension.
 885  */
 886 int X509v3_asid_validate_resource_set(STACK_OF(X509) *chain,
 887                                       ASIdentifiers *ext, int allow_inheritance)
 888 {
 889     if (ext == NULL)
 890         return 1;
 891     if (chain == NULL || sk_X509_num(chain) == 0)
 892         return 0;
 893     if (!allow_inheritance && X509v3_asid_inherits(ext))
 894         return 0;
 895     return asid_validate_path_internal(NULL, chain, ext);
 896 }
 897
 898 #endif                          /* OPENSSL_NO_RFC3779 */