/* x_bignum.c */
/* Written by Dr Stephen N Henson (shenson@bigfoot.com) for the OpenSSL
* project 2000.
*/
/* ====================================================================
* Copyright (c) 2000 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).
*
*/
#include <stdio.h>
#include "cryptlib.h"
#include <openssl/asn1t.h>
#include <openssl/bn.h>
/* Custom primitive type for BIGNUM handling. This reads in an ASN1_INTEGER as a
* BIGNUM directly. Currently it ignores the sign which isn't a problem since all
* BIGNUMs used are non negative and anything that looks negative is normally due
* to an encoding error.
*/
#define BN_SENSITIVE 1
static int bn_new(ASN1_VALUE **pval, const ASN1_ITEM *it);
static void bn_free(ASN1_VALUE **pval, const ASN1_ITEM *it);
static int bn_i2c(ASN1_VALUE **pval, unsigned char *cont, int *putype, const ASN1_ITEM *it);
static int bn_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len, int utype, char *free_cont, const ASN1_ITEM *it);
static ASN1_PRIMITIVE_FUNCS bignum_pf = {
NULL, 0,
bn_new,
bn_free,
0,
bn_c2i,
bn_i2c
};
ASN1_ITEM_start(BIGNUM)
ASN1_ITYPE_PRIMITIVE, V_ASN1_INTEGER, NULL, 0, &bignum_pf, 0, "BIGNUM"
ASN1_ITEM_end(BIGNUM)
ASN1_ITEM_start(CBIGNUM)
ASN1_ITYPE_PRIMITIVE, V_ASN1_INTEGER, NULL, 0, &bignum_pf, BN_SENSITIVE, "BIGNUM"
ASN1_ITEM_end(CBIGNUM)
static int bn_new(ASN1_VALUE **pval, const ASN1_ITEM *it)
{
*pval = (ASN1_VALUE *)BN_new();
if(*pval) return 1;
else return 0;
}
static void bn_free(ASN1_VALUE **pval, const ASN1_ITEM *it)
{
if(!*pval) return;
if(it->size & BN_SENSITIVE) BN_clear_free((BIGNUM *)*pval);
else BN_free((BIGNUM *)*pval);
*pval = NULL;
}
static int bn_i2c(ASN1_VALUE **pval, unsigned char *cont, int *putype, const ASN1_ITEM *it)
{
BIGNUM *bn;
int pad;
if(!*pval) return -1;
bn = (BIGNUM *)*pval;
/* If MSB set in an octet we need a padding byte */
if(BN_num_bits(bn) & 0x7) pad = 0;
else pad = 1;
if(cont) {
if(pad) *cont++ = 0;
BN_bn2bin(bn, cont);
}
return pad + BN_num_bytes(bn);
}
static int bn_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len,
int utype, char *free_cont, const ASN1_ITEM *it)
{
BIGNUM *bn;
if(!*pval) bn_new(pval, it);
bn = (BIGNUM *)*pval;
if(!BN_bin2bn(cont, len, bn)) {
bn_free(pval, it);
return 0;
}
return 1;
}
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