/*

 * Copyright (C) 2012 Red Hat Inc.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 *

 *     * Redistributions of source code must retain the above

 *       copyright notice, this list of conditions and the

 *       following disclaimer.

 *     * 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.

 *     * The names of contributors to this software may not be

 *       used to endorse or promote products derived from this

 *       software without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

 * "AS IS" AND ANY EXPRESS 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

 * COPYRIGHT OWNER OR 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.

 *

 * Author: Stef Walter <stefw@redhat.com>

 */

#include "config.h"

#include "hash.h"

#include "oid.h"

#include <assert.h>

#include <stdlib.h>

#include <stdint.h>

#include <string.h>

/*

 * We deal with OIDs a lot in their DER form. These have the

 * advantage of having the length encoded in their second byte,

 * at least for all the OIDs we're interested in.

 *

 * The goal here is to avoid carrying around extra length

 * information about DER encoded OIDs.

 */

bool

p11_oid_simple (const unsigned char *oid,

                int len)

{

  return (oid != NULL &&

          len > 3 &&                   /* minimum length */

          oid[0] == 0x06 &&            /* simple encoding */

          (oid[1] & 128) == 0 &&       /* short form length */

          (size_t)oid[1] == len - 2);  /* matches length */

}

unsigned int

p11_oid_hash (const void *oid)

{

  uint32_t hash;

  int len;

  len = p11_oid_length (oid);

  p11_hash_murmur3 (&hash, oid, len, NULL);

  return hash;

}

bool

p11_oid_equal (const void *oid_one,

               const void *oid_two)

{

  int len_one;

  int len_two;

  len_one = p11_oid_length (oid_one);

  len_two = p11_oid_length (oid_two);

  return (len_one == len_two &&

          memcmp (oid_one, oid_two, len_one) == 0);

}

int

p11_oid_length (const unsigned char *oid)

{

  assert (oid[0] == 0x06);

  assert ((oid[1] & 128) == 0);

  return (int)oid[1] + 2;

}