/src/libressl/crypto/x509/x509_asid.c

Source (jump to first uncovered line)
/*  $OpenBSD: x509_asid.c,v 1.35 2022/07/30 17:50:17 tb Exp $ */
/*
 * Contributed to the OpenSSL Project by the American Registry for
 * Internet Numbers ("ARIN").
 */
/* ====================================================================
 * Copyright (c) 2006-2018 The OpenSSL Project.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. All advertising materials mentioning features or use of this
 *    software must display the following acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
 *
 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
 *    endorse or promote products derived from this software without
 *    prior written permission. For written permission, please contact
 *    licensing@OpenSSL.org.
 *
 * 5. Products derived from this software may not be called "OpenSSL"
 *    nor may "OpenSSL" appear in their names without prior written
 *    permission of the OpenSSL Project.
 *
 * 6. Redistributions of any form whatsoever must retain the following
 *    acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
 *
 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 * ====================================================================
 *
 * This product includes cryptographic software written by Eric Young
 * (eay@cryptsoft.com).  This product includes software written by Tim
 * Hudson (tjh@cryptsoft.com).
 */

/*
 * Implementation of RFC 3779 section 3.2.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <openssl/asn1.h>
#include <openssl/asn1t.h>
#include <openssl/bn.h>
#include <openssl/conf.h>
#include <openssl/err.h>
#include <openssl/x509.h>
#include <openssl/x509.h>
#include <openssl/x509v3.h>

#include "x509_lcl.h"

#ifndef OPENSSL_NO_RFC3779

static const ASN1_TEMPLATE ASRange_seq_tt[] = {
  {
    .flags = 0,
    .tag = 0,
    .offset = offsetof(ASRange, min),
    .field_name = "min",
    .item = &ASN1_INTEGER_it,
  },
  {
    .flags = 0,
    .tag = 0,
    .offset = offsetof(ASRange, max),
    .field_name = "max",
    .item = &ASN1_INTEGER_it,
  },
};

const ASN1_ITEM ASRange_it = {
  .itype = ASN1_ITYPE_SEQUENCE,
  .utype = V_ASN1_SEQUENCE,
  .templates = ASRange_seq_tt,
  .tcount = sizeof(ASRange_seq_tt) / sizeof(ASN1_TEMPLATE),
  .funcs = NULL,
  .size = sizeof(ASRange),
  .sname = "ASRange",
};

static const ASN1_TEMPLATE ASIdOrRange_ch_tt[] = {
  {
    .flags = 0,
    .tag = 0,
    .offset = offsetof(ASIdOrRange, u.id),
    .field_name = "u.id",
    .item = &ASN1_INTEGER_it,
  },
  {
    .flags = 0,
    .tag = 0,
    .offset = offsetof(ASIdOrRange, u.range),
    .field_name = "u.range",
    .item = &ASRange_it,
  },
};

const ASN1_ITEM ASIdOrRange_it = {
  .itype = ASN1_ITYPE_CHOICE,
  .utype = offsetof(ASIdOrRange, type),
  .templates = ASIdOrRange_ch_tt,
  .tcount = sizeof(ASIdOrRange_ch_tt) / sizeof(ASN1_TEMPLATE),
  .funcs = NULL,
  .size = sizeof(ASIdOrRange),
  .sname = "ASIdOrRange",
};

static const ASN1_TEMPLATE ASIdentifierChoice_ch_tt[] = {
  {
    .flags = 0,
    .tag = 0,
    .offset = offsetof(ASIdentifierChoice, u.inherit),
    .field_name = "u.inherit",
    .item = &ASN1_NULL_it,
  },
  {
    .flags = ASN1_TFLG_SEQUENCE_OF,
    .tag = 0,
    .offset = offsetof(ASIdentifierChoice, u.asIdsOrRanges),
    .field_name = "u.asIdsOrRanges",
    .item = &ASIdOrRange_it,
  },
};

const ASN1_ITEM ASIdentifierChoice_it = {
  .itype = ASN1_ITYPE_CHOICE,
  .utype = offsetof(ASIdentifierChoice, type),
  .templates = ASIdentifierChoice_ch_tt,
  .tcount = sizeof(ASIdentifierChoice_ch_tt) / sizeof(ASN1_TEMPLATE),
  .funcs = NULL,
  .size = sizeof(ASIdentifierChoice),
  .sname = "ASIdentifierChoice",
};

static const ASN1_TEMPLATE ASIdentifiers_seq_tt[] = {
  {
    .flags = ASN1_TFLG_EXPLICIT | ASN1_TFLG_OPTIONAL,
    .tag = 0,
    .offset = offsetof(ASIdentifiers, asnum),
    .field_name = "asnum",
    .item = &ASIdentifierChoice_it,
  },
  {
    .flags = ASN1_TFLG_EXPLICIT | ASN1_TFLG_OPTIONAL,
    .tag = 1,
    .offset = offsetof(ASIdentifiers, rdi),
    .field_name = "rdi",
    .item = &ASIdentifierChoice_it,
  },
};

const ASN1_ITEM ASIdentifiers_it = {
  .itype = ASN1_ITYPE_SEQUENCE,
  .utype = V_ASN1_SEQUENCE,
  .templates = ASIdentifiers_seq_tt,
  .tcount = sizeof(ASIdentifiers_seq_tt) / sizeof(ASN1_TEMPLATE),
  .funcs = NULL,
  .size = sizeof(ASIdentifiers),
  .sname = "ASIdentifiers",
};

ASRange *
d2i_ASRange(ASRange **a, const unsigned char **in, long len)
{
  return (ASRange *)ASN1_item_d2i((ASN1_VALUE **)a, in, len,
      &ASRange_it);
}

int
i2d_ASRange(ASRange *a, unsigned char **out)
{
  return ASN1_item_i2d((ASN1_VALUE *)a, out, &ASRange_it);
}

ASRange *
ASRange_new(void)
{
  return (ASRange *)ASN1_item_new(&ASRange_it);
}

void
ASRange_free(ASRange *a)
{
  ASN1_item_free((ASN1_VALUE *)a, &ASRange_it);
}

ASIdOrRange *
d2i_ASIdOrRange(ASIdOrRange **a, const unsigned char **in, long len)
{
  return (ASIdOrRange *)ASN1_item_d2i((ASN1_VALUE **)a, in, len,
      &ASIdOrRange_it);
}

int
i2d_ASIdOrRange(ASIdOrRange *a, unsigned char **out)
{
  return ASN1_item_i2d((ASN1_VALUE *)a, out, &ASIdOrRange_it);
}

ASIdOrRange *
ASIdOrRange_new(void)
{
  return (ASIdOrRange *)ASN1_item_new(&ASIdOrRange_it);
}

void
ASIdOrRange_free(ASIdOrRange *a)
{
  ASN1_item_free((ASN1_VALUE *)a, &ASIdOrRange_it);
}

ASIdentifierChoice *
d2i_ASIdentifierChoice(ASIdentifierChoice **a, const unsigned char **in,
    long len)
{
  return (ASIdentifierChoice *)ASN1_item_d2i((ASN1_VALUE **)a, in, len,
      &ASIdentifierChoice_it);
}

int
i2d_ASIdentifierChoice(ASIdentifierChoice *a, unsigned char **out)
{
  return ASN1_item_i2d((ASN1_VALUE *)a, out, &ASIdentifierChoice_it);
}

ASIdentifierChoice *
ASIdentifierChoice_new(void)
{
  return (ASIdentifierChoice *)ASN1_item_new(&ASIdentifierChoice_it);
}

void
ASIdentifierChoice_free(ASIdentifierChoice *a)
{
  ASN1_item_free((ASN1_VALUE *)a, &ASIdentifierChoice_it);
}

ASIdentifiers *
d2i_ASIdentifiers(ASIdentifiers **a, const unsigned char **in, long len)
{
  return (ASIdentifiers *)ASN1_item_d2i((ASN1_VALUE **)a, in, len,
      &ASIdentifiers_it);
}

int
i2d_ASIdentifiers(ASIdentifiers *a, unsigned char **out)
{
  return ASN1_item_i2d((ASN1_VALUE *)a, out, &ASIdentifiers_it);
}

ASIdentifiers *
ASIdentifiers_new(void)
{
  return (ASIdentifiers *)ASN1_item_new(&ASIdentifiers_it);
}

void
ASIdentifiers_free(ASIdentifiers *a)
{
  ASN1_item_free((ASN1_VALUE *)a, &ASIdentifiers_it);
}

/*
 * i2r method for an ASIdentifierChoice.
 */
static int
i2r_ASIdentifierChoice(BIO *out, ASIdentifierChoice *choice, int indent,
    const char *msg)
{
  int i;
  char *s;
  if (choice == NULL)
    return 1;
  BIO_printf(out, "%*s%s:\n", indent, "", msg);
  switch (choice->type) {
  case ASIdentifierChoice_inherit:
    BIO_printf(out, "%*sinherit\n", indent + 2, "");
    break;
  case ASIdentifierChoice_asIdsOrRanges:
    for (i = 0; i < sk_ASIdOrRange_num(choice->u.asIdsOrRanges);
        i++) {
      ASIdOrRange *aor =
          sk_ASIdOrRange_value(choice->u.asIdsOrRanges, i);
      switch (aor->type) {
      case ASIdOrRange_id:
        if ((s = i2s_ASN1_INTEGER(NULL, aor->u.id)) ==
            NULL)
          return 0;
        BIO_printf(out, "%*s%s\n", indent + 2, "", s);
        free(s);
        break;
      case ASIdOrRange_range:
        if ((s = i2s_ASN1_INTEGER(NULL,
            aor->u.range->min)) == NULL)
          return 0;
        BIO_printf(out, "%*s%s-", indent + 2, "", s);
        free(s);
        if ((s = i2s_ASN1_INTEGER(NULL,
            aor->u.range->max)) == NULL)
          return 0;
        BIO_printf(out, "%s\n", s);
        free(s);
        break;
      default:
        return 0;
      }
    }
    break;
  default:
    return 0;
  }
  return 1;
}

/*
 * i2r method for an ASIdentifier extension.
 */
static int
i2r_ASIdentifiers(const X509V3_EXT_METHOD *method, void *ext, BIO *out,
    int indent)
{
  ASIdentifiers *asid = ext;
  return (i2r_ASIdentifierChoice(out, asid->asnum, indent,
      "Autonomous System Numbers") &&
      i2r_ASIdentifierChoice(out, asid->rdi, indent,
      "Routing Domain Identifiers"));
}

/*
 * Sort comparison function for a sequence of ASIdOrRange elements.
 */
static int
ASIdOrRange_cmp(const ASIdOrRange *const *a_, const ASIdOrRange *const *b_)
{
  const ASIdOrRange *a = *a_, *b = *b_;

  /* XXX: these asserts need to be replaced */
  OPENSSL_assert((a->type == ASIdOrRange_id && a->u.id != NULL) ||
      (a->type == ASIdOrRange_range && a->u.range != NULL &&
       a->u.range->min != NULL && a->u.range->max != NULL));

  OPENSSL_assert((b->type == ASIdOrRange_id && b->u.id != NULL) ||
      (b->type == ASIdOrRange_range && b->u.range != NULL &&
       b->u.range->min != NULL && b->u.range->max != NULL));

  if (a->type == ASIdOrRange_id && b->type == ASIdOrRange_id)
    return ASN1_INTEGER_cmp(a->u.id, b->u.id);

  if (a->type == ASIdOrRange_range && b->type == ASIdOrRange_range) {
    int r = ASN1_INTEGER_cmp(a->u.range->min, b->u.range->min);
    return r != 0 ? r : ASN1_INTEGER_cmp(a->u.range->max,
        b->u.range->max);
  }

  if (a->type == ASIdOrRange_id)
    return ASN1_INTEGER_cmp(a->u.id, b->u.range->min);
  else
    return ASN1_INTEGER_cmp(a->u.range->min, b->u.id);
}

/*
 * Add an inherit element.
 */
int
X509v3_asid_add_inherit(ASIdentifiers *asid, int which)
{
  ASIdentifierChoice **choice;
  if (asid == NULL)
    return 0;
  switch (which) {
  case V3_ASID_ASNUM:
    choice = &asid->asnum;
    break;
  case V3_ASID_RDI:
    choice = &asid->rdi;
    break;
  default:
    return 0;
  }
  if (*choice == NULL) {
    if ((*choice = ASIdentifierChoice_new()) == NULL)
      return 0;
    if (((*choice)->u.inherit = ASN1_NULL_new()) == NULL)
      return 0;
    (*choice)->type = ASIdentifierChoice_inherit;
  }
  return (*choice)->type == ASIdentifierChoice_inherit;
}

/*
 * Add an ID or range to an ASIdentifierChoice.
 */
int
X509v3_asid_add_id_or_range(ASIdentifiers *asid, int which, ASN1_INTEGER *min,
    ASN1_INTEGER *max)
{
  ASIdentifierChoice **choice;
  ASIdOrRange *aor;
  if (asid == NULL)
    return 0;
  switch (which) {
  case V3_ASID_ASNUM:
    choice = &asid->asnum;
    break;
  case V3_ASID_RDI:
    choice = &asid->rdi;
    break;
  default:
    return 0;
  }
  if (*choice != NULL && (*choice)->type == ASIdentifierChoice_inherit)
    return 0;
  if (*choice == NULL) {
    if ((*choice = ASIdentifierChoice_new()) == NULL)
      return 0;
    (*choice)->u.asIdsOrRanges = sk_ASIdOrRange_new(ASIdOrRange_cmp);
    if ((*choice)->u.asIdsOrRanges == NULL)
      return 0;
    (*choice)->type = ASIdentifierChoice_asIdsOrRanges;
  }
  if ((aor = ASIdOrRange_new()) == NULL)
    return 0;
  if (max == NULL) {
    aor->type = ASIdOrRange_id;
    aor->u.id = min;
  } else {
    aor->type = ASIdOrRange_range;
    if ((aor->u.range = ASRange_new()) == NULL)
      goto err;
    ASN1_INTEGER_free(aor->u.range->min);
    aor->u.range->min = min;
    ASN1_INTEGER_free(aor->u.range->max);
    aor->u.range->max = max;
  }
  if (!(sk_ASIdOrRange_push((*choice)->u.asIdsOrRanges, aor)))
    goto err;
  return 1;

 err:
  ASIdOrRange_free(aor);
  return 0;
}

/*
 * Extract min and max values from an ASIdOrRange.
 */
static int
extract_min_max(ASIdOrRange *aor, ASN1_INTEGER **min, ASN1_INTEGER **max)
{
  switch (aor->type) {
  case ASIdOrRange_id:
    *min = aor->u.id;
    *max = aor->u.id;
    return 1;
  case ASIdOrRange_range:
    *min = aor->u.range->min;
    *max = aor->u.range->max;
    return 1;
  }

  return 0;
}

/*
 * Check whether an ASIdentifierChoice is in canonical form.
 */
static int
ASIdentifierChoice_is_canonical(ASIdentifierChoice *choice)
{
  ASN1_INTEGER *a_max_plus_one = NULL;
  ASN1_INTEGER *orig;
  BIGNUM *bn = NULL;
  int i, ret = 0;

  /*
   * Empty element or inheritance is canonical.
   */
  if (choice == NULL || choice->type == ASIdentifierChoice_inherit)
    return 1;

  /*
   * If not a list, or if empty list, it's broken.
   */
  if (choice->type != ASIdentifierChoice_asIdsOrRanges ||
      sk_ASIdOrRange_num(choice->u.asIdsOrRanges) == 0)
    return 0;

  /*
   * It's a list, check it.
   */
  for (i = 0; i < sk_ASIdOrRange_num(choice->u.asIdsOrRanges) - 1; i++) {
    ASIdOrRange *a = sk_ASIdOrRange_value(choice->u.asIdsOrRanges,
        i);
    ASIdOrRange *b = sk_ASIdOrRange_value(choice->u.asIdsOrRanges,
        i + 1);
    ASN1_INTEGER *a_min = NULL,
    *a_max = NULL,
    *b_min = NULL,
    *b_max =
        NULL;

    if (!extract_min_max(a, &a_min, &a_max) ||
        !extract_min_max(b, &b_min, &b_max))
      goto done;

    /*
     * Punt misordered list, overlapping start, or inverted range.
     */
    if (ASN1_INTEGER_cmp(a_min, b_min) >= 0 ||
        ASN1_INTEGER_cmp(a_min, a_max) > 0 ||
        ASN1_INTEGER_cmp(b_min, b_max) > 0)
      goto done;

    /*
     * Calculate a_max + 1 to check for adjacency.
     */
    if ((bn == NULL && (bn = BN_new()) == NULL) ||
        ASN1_INTEGER_to_BN(a_max, bn) == NULL ||
        !BN_add_word(bn, 1)) {
      X509V3error(ERR_R_MALLOC_FAILURE);
      goto done;
    }

    if ((a_max_plus_one =
        BN_to_ASN1_INTEGER(bn, orig = a_max_plus_one)) == NULL) {
      a_max_plus_one = orig;
      X509V3error(ERR_R_MALLOC_FAILURE);
      goto done;
    }

    /*
     * Punt if adjacent or overlapping.
     */
    if (ASN1_INTEGER_cmp(a_max_plus_one, b_min) >= 0)
      goto done;
  }

  /*
  * Check for inverted range.
  */
  i = sk_ASIdOrRange_num(choice->u.asIdsOrRanges) - 1;
  {
    ASIdOrRange *a = sk_ASIdOrRange_value(choice->u.asIdsOrRanges,
        i);
    ASN1_INTEGER *a_min, *a_max;
    if (a != NULL && a->type == ASIdOrRange_range) {
      if (!extract_min_max(a, &a_min, &a_max) ||
          ASN1_INTEGER_cmp(a_min, a_max) > 0)
        goto done;
    }
  }

  ret = 1;

 done:
  ASN1_INTEGER_free(a_max_plus_one);
  BN_free(bn);
  return ret;
}

/*
 * Check whether an ASIdentifier extension is in canonical form.
 */
int
X509v3_asid_is_canonical(ASIdentifiers *asid)
{
  return (asid == NULL ||
      (ASIdentifierChoice_is_canonical(asid->asnum) &&
       ASIdentifierChoice_is_canonical(asid->rdi)));
}

/*
 * Whack an ASIdentifierChoice into canonical form.
 */
static int
ASIdentifierChoice_canonize(ASIdentifierChoice *choice)
{
  ASN1_INTEGER *a_max_plus_one = NULL;
  ASN1_INTEGER *orig;
  BIGNUM *bn = NULL;
  int i, ret = 0;

  /*
   * Nothing to do for empty element or inheritance.
   */
  if (choice == NULL || choice->type == ASIdentifierChoice_inherit)
    return 1;

  /*
   * If not a list, or if empty list, it's broken.
   */
  if (choice->type != ASIdentifierChoice_asIdsOrRanges ||
      sk_ASIdOrRange_num(choice->u.asIdsOrRanges) == 0) {
    X509V3error(X509V3_R_EXTENSION_VALUE_ERROR);
    return 0;
  }

  /*
   * We have a non-empty list.  Sort it.
   */
  sk_ASIdOrRange_sort(choice->u.asIdsOrRanges);

  /*
   * Now check for errors and suboptimal encoding, rejecting the
   * former and fixing the latter.
   */
  for (i = 0; i < sk_ASIdOrRange_num(choice->u.asIdsOrRanges) - 1; i++) {
    ASIdOrRange *a = sk_ASIdOrRange_value(choice->u.asIdsOrRanges,
        i);
    ASIdOrRange *b = sk_ASIdOrRange_value(choice->u.asIdsOrRanges,
        i + 1);
    ASN1_INTEGER *a_min = NULL,
    *a_max = NULL,
    *b_min = NULL,
    *b_max =
        NULL;

    if (!extract_min_max(a, &a_min, &a_max) ||
        !extract_min_max(b, &b_min, &b_max))
      goto done;

    /*
     * Make sure we're properly sorted (paranoia).
     */
    if (ASN1_INTEGER_cmp(a_min, b_min) > 0)
      goto done;

    /*
     * Punt inverted ranges.
     */
    if (ASN1_INTEGER_cmp(a_min, a_max) > 0 ||
        ASN1_INTEGER_cmp(b_min, b_max) > 0)
      goto done;

    /*
     * Check for overlaps.
     */
    if (ASN1_INTEGER_cmp(a_max, b_min) >= 0) {
      X509V3error(X509V3_R_EXTENSION_VALUE_ERROR);
      goto done;
    }

    /*
     * Calculate a_max + 1 to check for adjacency.
     */
    if ((bn == NULL && (bn = BN_new()) == NULL) ||
        ASN1_INTEGER_to_BN(a_max, bn) == NULL ||
        !BN_add_word(bn, 1)) {
      X509V3error(ERR_R_MALLOC_FAILURE);
      goto done;
    }

    if ((a_max_plus_one =
        BN_to_ASN1_INTEGER(bn, orig = a_max_plus_one)) == NULL) {
      a_max_plus_one = orig;
      X509V3error(ERR_R_MALLOC_FAILURE);
      goto done;
    }

    /*
     * If a and b are adjacent, merge them.
     */
    if (ASN1_INTEGER_cmp(a_max_plus_one, b_min) == 0) {
      ASRange *r;
      switch (a->type) {
      case ASIdOrRange_id:
        if ((r = calloc(1, sizeof(*r))) == NULL) {
          X509V3error(ERR_R_MALLOC_FAILURE);
          goto done;
        }
        r->min = a_min;
        r->max = b_max;
        a->type = ASIdOrRange_range;
        a->u.range = r;
        break;
      case ASIdOrRange_range:
        ASN1_INTEGER_free(a->u.range->max);
        a->u.range->max = b_max;
        break;
      }
      switch (b->type) {
      case ASIdOrRange_id:
        b->u.id = NULL;
        break;
      case ASIdOrRange_range:
        b->u.range->max = NULL;
        break;
      }
      ASIdOrRange_free(b);
      (void)sk_ASIdOrRange_delete(choice->u.asIdsOrRanges,
          i + 1);
      i--;
      continue;
    }
  }

  /*
   * Check for final inverted range.
   */
  i = sk_ASIdOrRange_num(choice->u.asIdsOrRanges) - 1;
  {
    ASIdOrRange *a = sk_ASIdOrRange_value(choice->u.asIdsOrRanges,
        i);
    ASN1_INTEGER *a_min, *a_max;
    if (a != NULL && a->type == ASIdOrRange_range) {
      if (!extract_min_max(a, &a_min, &a_max) ||
          ASN1_INTEGER_cmp(a_min, a_max) > 0)
        goto done;
    }
  }

  /* Paranoia */
  if (!ASIdentifierChoice_is_canonical(choice))
    goto done;

  ret = 1;

 done:
  ASN1_INTEGER_free(a_max_plus_one);
  BN_free(bn);
  return ret;
}

/*
 * Whack an ASIdentifier extension into canonical form.
 */
int
X509v3_asid_canonize(ASIdentifiers *asid)
{
  if (asid == NULL)
    return 1;

  if (!ASIdentifierChoice_canonize(asid->asnum))
    return 0;

  return ASIdentifierChoice_canonize(asid->rdi);
}

/*
 * v2i method for an ASIdentifier extension.
 */
static void *
v2i_ASIdentifiers(const struct v3_ext_method *method, struct v3_ext_ctx *ctx,
    STACK_OF(CONF_VALUE)*values)
{
  ASN1_INTEGER *min = NULL, *max = NULL;
  ASIdentifiers *asid = NULL;
  int i;

  if ((asid = ASIdentifiers_new()) == NULL) {
    X509V3error(ERR_R_MALLOC_FAILURE);
    return NULL;
  }

  for (i = 0; i < sk_CONF_VALUE_num(values); i++) {
    CONF_VALUE *val = sk_CONF_VALUE_value(values, i);
    int i1 = 0, i2 = 0, i3 = 0, is_range = 0, which = 0;

    /*
     * Figure out whether this is an AS or an RDI.
     */
    if (!name_cmp(val->name, "AS")) {
      which = V3_ASID_ASNUM;
    } else if (!name_cmp(val->name, "RDI")) {
      which = V3_ASID_RDI;
    } else {
      X509V3error(X509V3_R_EXTENSION_NAME_ERROR);
      X509V3_conf_err(val);
      goto err;
    }

    /*
     * Handle inheritance.
     */
    if (strcmp(val->value, "inherit") == 0) {
      if (X509v3_asid_add_inherit(asid, which))
        continue;
      X509V3error(X509V3_R_INVALID_INHERITANCE);
      X509V3_conf_err(val);
      goto err;
    }

    /*
     * Number, range, or mistake, pick it apart and figure out which
     */
    i1 = strspn(val->value, "0123456789");
    if (val->value[i1] == '\0') {
      is_range = 0;
    } else {
      is_range = 1;
      i2 = i1 + strspn(val->value + i1, " \t");
      if (val->value[i2] != '-') {
        X509V3error(X509V3_R_INVALID_ASNUMBER);
        X509V3_conf_err(val);
        goto err;
      }
      i2++;
      i2 = i2 + strspn(val->value + i2, " \t");
      i3 = i2 + strspn(val->value + i2, "0123456789");
      if (val->value[i3] != '\0') {
        X509V3error(X509V3_R_INVALID_ASRANGE);
        X509V3_conf_err(val);
        goto err;
      }
    }

    /*
     * Syntax is ok, read and add it.
     */
    if (!is_range) {
      if (!X509V3_get_value_int(val, &min)) {
        X509V3error(ERR_R_MALLOC_FAILURE);
        goto err;
      }
    } else {
      char *s = strdup(val->value);
      if (s == NULL) {
        X509V3error(ERR_R_MALLOC_FAILURE);
        goto err;
      }
      s[i1] = '\0';
      min = s2i_ASN1_INTEGER(NULL, s);
      max = s2i_ASN1_INTEGER(NULL, s + i2);
      free(s);
      if (min == NULL || max == NULL) {
        X509V3error(ERR_R_MALLOC_FAILURE);
        goto err;
      }
      if (ASN1_INTEGER_cmp(min, max) > 0) {
        X509V3error(X509V3_R_EXTENSION_VALUE_ERROR);
        goto err;
      }
    }
    if (!X509v3_asid_add_id_or_range(asid, which, min, max)) {
      X509V3error(ERR_R_MALLOC_FAILURE);
      goto err;
    }
    min = max = NULL;
  }

  /*
   * Canonize the result, then we're done.
   */
  if (!X509v3_asid_canonize(asid))
    goto err;
  return asid;

 err:
  ASIdentifiers_free(asid);
  ASN1_INTEGER_free(min);
  ASN1_INTEGER_free(max);
  return NULL;
}

/*
 * OpenSSL dispatch.
 */
const X509V3_EXT_METHOD v3_asid = {
  .ext_nid = NID_sbgp_autonomousSysNum,
  .ext_flags = 0,
  .it = &ASIdentifiers_it,
  .ext_new = NULL,
  .ext_free = NULL,
  .d2i = NULL,
  .i2d = NULL,
  .i2s = NULL,
  .s2i = NULL,
  .i2v = NULL,
  .v2i = v2i_ASIdentifiers,
  .i2r = i2r_ASIdentifiers,
  .r2i = NULL,
  .usr_data = NULL,
};

/*
 * Figure out whether extension uses inheritance.
 */
int
X509v3_asid_inherits(ASIdentifiers *asid)
{
  if (asid == NULL)
    return 0;

  if (asid->asnum != NULL) {
    if (asid->asnum->type == ASIdentifierChoice_inherit)
      return 1;
  }

  if (asid->rdi != NULL) {
    if (asid->rdi->type == ASIdentifierChoice_inherit)
      return 1;
  }

  return 0;
}

/*
 * Figure out whether parent contains child.
 */
static int
asid_contains(ASIdOrRanges *parent, ASIdOrRanges *child)
{
  ASN1_INTEGER *p_min = NULL, *p_max = NULL, *c_min = NULL, *c_max = NULL;
  int p, c;

  if (child == NULL || parent == child)
    return 1;

  if (parent == NULL)
    return 0;

  p = 0;
  for (c = 0; c < sk_ASIdOrRange_num(child); c++) {
    if (!extract_min_max(sk_ASIdOrRange_value(child, c), &c_min,
        &c_max))
      return 0;
    for (;; p++) {
      if (p >= sk_ASIdOrRange_num(parent))
        return 0;
      if (!extract_min_max(sk_ASIdOrRange_value(parent, p),
          &p_min, &p_max))
        return 0;
      if (ASN1_INTEGER_cmp(p_max, c_max) < 0)
        continue;
      if (ASN1_INTEGER_cmp(p_min, c_min) > 0)
        return 0;
      break;
    }
  }

  return 1;
}

/*
 * Test whether child is a subset of parent.
 */
int
X509v3_asid_subset(ASIdentifiers *child, ASIdentifiers *parent)
{
  if (child == NULL || child == parent)
    return 1;

  if (parent == NULL)
    return 0;

  if (X509v3_asid_inherits(child) || X509v3_asid_inherits(parent))
    return 0;

  if (child->asnum != NULL) {
    if (parent->asnum == NULL)
      return 0;

    if (!asid_contains(parent->asnum->u.asIdsOrRanges,
        child->asnum->u.asIdsOrRanges))
      return 0;
  }

  if (child->rdi != NULL) {
    if (parent->rdi == NULL)
      return 0;

    if (!asid_contains(parent->rdi->u.asIdsOrRanges,
        child->rdi->u.asIdsOrRanges))
      return 0;
  }

  return 1;
}

/*
 * Validation error handling via callback.
 */
#define validation_err(_err_)           \
  do {                                  \
    if (ctx != NULL) {                  \
      ctx->error = _err_;               \
      ctx->error_depth = i;             \
      ctx->current_cert = x;            \
      ret = ctx->verify_cb(0, ctx);     \
    } else {                            \
      ret = 0;                          \
    }                                   \
    if (!ret)                           \
      goto done;                        \
  } while (0)

/*
 * Core code for RFC 3779 3.3 path validation.
 */
static int
asid_validate_path_internal(X509_STORE_CTX *ctx, STACK_OF(X509) *chain,
    ASIdentifiers *ext)
{
  ASIdOrRanges *child_as = NULL, *child_rdi = NULL;
  int i, ret = 1, inherit_as = 0, inherit_rdi = 0;
  X509 *x;

  /* We need a non-empty chain to test against. */
  if (sk_X509_num(chain) <= 0)
    goto err;
  /* We need either a store ctx or an extension to work with. */
  if (ctx == NULL && ext == NULL)
    goto err;
  /* If there is a store ctx, it needs a verify_cb. */
  if (ctx != NULL && ctx->verify_cb == NULL)
    goto err;

  /*
   * Figure out where to start. If we don't have an extension to check,
   * (either extracted from the leaf or passed by the caller), we're done.
   * Otherwise, check canonical form and set up for walking up the chain.
   */
  if (ext != NULL) {
    i = -1;
    x = NULL;
    if (!X509v3_asid_is_canonical(ext))
      validation_err(X509_V_ERR_INVALID_EXTENSION);
  } else {
    i = 0;
    x = sk_X509_value(chain, i);
    if ((X509_get_extension_flags(x) & EXFLAG_INVALID) != 0)
      goto done;
    if ((ext = x->rfc3779_asid) == NULL)
      goto done;
  }
  if (ext->asnum != NULL) {
    switch (ext->asnum->type) {
    case ASIdentifierChoice_inherit:
      inherit_as = 1;
      break;
    case ASIdentifierChoice_asIdsOrRanges:
      child_as = ext->asnum->u.asIdsOrRanges;
      break;
    }
  }
  if (ext->rdi != NULL) {
    switch (ext->rdi->type) {
    case ASIdentifierChoice_inherit:
      inherit_rdi = 1;
      break;
    case ASIdentifierChoice_asIdsOrRanges:
      child_rdi = ext->rdi->u.asIdsOrRanges;
      break;
    }
  }

  /*
   * Now walk up the chain.  Extensions must be in canonical form, no
   * cert may list resources that its parent doesn't list.
   */
  for (i++; i < sk_X509_num(chain); i++) {
    x = sk_X509_value(chain, i);

    if ((X509_get_extension_flags(x) & EXFLAG_INVALID) != 0)
      validation_err(X509_V_ERR_INVALID_EXTENSION);
    if (x->rfc3779_asid == NULL) {
      if (child_as != NULL || child_rdi != NULL)
        validation_err(X509_V_ERR_UNNESTED_RESOURCE);
      continue;
    }
    if (x->rfc3779_asid->asnum == NULL && child_as != NULL) {
      validation_err(X509_V_ERR_UNNESTED_RESOURCE);
      child_as = NULL;
      inherit_as = 0;
    }
    if (x->rfc3779_asid->asnum != NULL &&
        x->rfc3779_asid->asnum->type ==
        ASIdentifierChoice_asIdsOrRanges) {
      if (inherit_as ||
          asid_contains(x->rfc3779_asid->asnum->u.asIdsOrRanges,
          child_as)) {
        child_as = x->rfc3779_asid->asnum->u.asIdsOrRanges;
        inherit_as = 0;
      } else {
        validation_err(X509_V_ERR_UNNESTED_RESOURCE);
      }
    }
    if (x->rfc3779_asid->rdi == NULL && child_rdi != NULL) {
      validation_err(X509_V_ERR_UNNESTED_RESOURCE);
      child_rdi = NULL;
      inherit_rdi = 0;
    }
    if (x->rfc3779_asid->rdi != NULL &&
        x->rfc3779_asid->rdi->type == ASIdentifierChoice_asIdsOrRanges) {
      if (inherit_rdi ||
          asid_contains(x->rfc3779_asid->rdi->u.asIdsOrRanges,
          child_rdi)) {
        child_rdi = x->rfc3779_asid->rdi->u.asIdsOrRanges;
        inherit_rdi = 0;
      } else {
        validation_err(X509_V_ERR_UNNESTED_RESOURCE);
      }
    }
  }

  /*
   * Trust anchor can't inherit.
   */

  if (x == NULL)
    goto err;

  if (x->rfc3779_asid != NULL) {
    if (x->rfc3779_asid->asnum != NULL &&
        x->rfc3779_asid->asnum->type == ASIdentifierChoice_inherit)
      validation_err(X509_V_ERR_UNNESTED_RESOURCE);
    if (x->rfc3779_asid->rdi != NULL &&
        x->rfc3779_asid->rdi->type == ASIdentifierChoice_inherit)
      validation_err(X509_V_ERR_UNNESTED_RESOURCE);
  }

 done:
  return ret;

 err:
  if (ctx != NULL)
    ctx->error = X509_V_ERR_UNSPECIFIED;

  return 0;
}

#undef validation_err

/*
 * RFC 3779 3.3 path validation -- called from X509_verify_cert().
 */
int
X509v3_asid_validate_path(X509_STORE_CTX *ctx)
{
  if (sk_X509_num(ctx->chain) <= 0 || ctx->verify_cb == NULL) {
    ctx->error = X509_V_ERR_UNSPECIFIED;
    return 0;
  }
  return asid_validate_path_internal(ctx, ctx->chain, NULL);
}

/*
 * RFC 3779 3.3 path validation of an extension.
 * Test whether chain covers extension.
 */
int
X509v3_asid_validate_resource_set(STACK_OF(X509) *chain, ASIdentifiers *ext,
    int allow_inheritance)
{
  if (ext == NULL)
    return 1;
  if (sk_X509_num(chain) <= 0)
    return 0;
  if (!allow_inheritance && X509v3_asid_inherits(ext))
    return 0;
  return asid_validate_path_internal(NULL, chain, ext);
}

#endif                          /* OPENSSL_NO_RFC3779 */

Coverage Report

Created: 2022-08-24 06:30