452 lines
11 KiB
C
452 lines
11 KiB
C
/* crypto/ecdsa/ecs_ossl.c */
|
|
/* ====================================================================
|
|
* Copyright (c) 1998-2002 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
|
|
* openssl-core@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 "ecdsa.h"
|
|
#include <openssl/err.h>
|
|
#include <openssl/obj_mac.h>
|
|
|
|
static ECDSA_SIG *ecdsa_do_sign(const unsigned char *dgst, int dlen,
|
|
EC_KEY *eckey);
|
|
static int ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, BIGNUM **kinvp,
|
|
BIGNUM **rp);
|
|
static int ecdsa_do_verify(const unsigned char *dgst, int dgst_len,
|
|
ECDSA_SIG *sig, EC_KEY *eckey);
|
|
|
|
static ECDSA_METHOD openssl_ecdsa_meth = {
|
|
"OpenSSL ECDSA method",
|
|
ecdsa_do_sign,
|
|
ecdsa_sign_setup,
|
|
ecdsa_do_verify,
|
|
#if 0
|
|
NULL, /* init */
|
|
NULL, /* finish */
|
|
#endif
|
|
0, /* flags */
|
|
NULL /* app_data */
|
|
};
|
|
|
|
const ECDSA_METHOD *ECDSA_OpenSSL(void)
|
|
{
|
|
return &openssl_ecdsa_meth;
|
|
}
|
|
|
|
static int ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, BIGNUM **kinvp,
|
|
BIGNUM **rp)
|
|
{
|
|
BN_CTX *ctx = NULL;
|
|
BIGNUM k,*kinv=NULL,*r=NULL,*order=NULL,*X=NULL;
|
|
EC_POINT *tmp_point=NULL;
|
|
int ret = 0;
|
|
if (!eckey || !eckey->group || !eckey->pub_key || !eckey->priv_key)
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_PASSED_NULL_PARAMETER);
|
|
return 0;
|
|
}
|
|
if (ctx_in == NULL)
|
|
{
|
|
if ((ctx=BN_CTX_new()) == NULL)
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_MALLOC_FAILURE);
|
|
goto err;
|
|
}
|
|
}
|
|
else
|
|
ctx=ctx_in;
|
|
|
|
if ((r = BN_new()) == NULL)
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
|
|
goto err;
|
|
}
|
|
if ((order = BN_new()) == NULL)
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
|
|
goto err;
|
|
}
|
|
if ((X = BN_new()) == NULL)
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
|
|
goto err;
|
|
}
|
|
if ((tmp_point = EC_POINT_new(eckey->group)) == NULL)
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB);
|
|
goto err;
|
|
}
|
|
if (!EC_GROUP_get_order(eckey->group,order,ctx))
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB);
|
|
goto err;
|
|
}
|
|
|
|
do
|
|
{
|
|
/* get random k */
|
|
BN_init(&k);
|
|
do
|
|
if (!BN_rand_range(&k,order))
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP,
|
|
ECDSA_R_RANDOM_NUMBER_GENERATION_FAILED);
|
|
goto err;
|
|
}
|
|
while (BN_is_zero(&k));
|
|
|
|
/* compute r the x-coordinate of generator * k */
|
|
if (!EC_POINT_mul(eckey->group, tmp_point, &k, NULL, NULL, ctx))
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB);
|
|
goto err;
|
|
}
|
|
if (EC_METHOD_get_field_type(EC_GROUP_method_of(eckey->group))
|
|
== NID_X9_62_prime_field)
|
|
{
|
|
if (!EC_POINT_get_affine_coordinates_GFp(eckey->group,
|
|
tmp_point, X, NULL, ctx))
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP,
|
|
ERR_R_EC_LIB);
|
|
goto err;
|
|
}
|
|
}
|
|
else /* NID_X9_62_characteristic_two_field */
|
|
{
|
|
if (!EC_POINT_get_affine_coordinates_GF2m(eckey->group,
|
|
tmp_point, X, NULL, ctx))
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP,
|
|
ERR_R_EC_LIB);
|
|
goto err;
|
|
}
|
|
}
|
|
if (!BN_nnmod(r,X,order,ctx))
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
|
|
goto err;
|
|
}
|
|
}
|
|
while (BN_is_zero(r));
|
|
|
|
/* compute the inverse of k */
|
|
if ((kinv = BN_mod_inverse(NULL,&k,order,ctx)) == NULL)
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
|
|
goto err;
|
|
}
|
|
|
|
if (*rp == NULL)
|
|
BN_clear_free(*rp);
|
|
*rp = r;
|
|
if (*kinvp == NULL)
|
|
BN_clear_free(*kinvp);
|
|
*kinvp = kinv;
|
|
kinv = NULL;
|
|
ret = 1;
|
|
err:
|
|
if (!ret)
|
|
{
|
|
if (kinv != NULL) BN_clear_free(kinv);
|
|
if (r != NULL) BN_clear_free(r);
|
|
}
|
|
if (ctx_in == NULL)
|
|
BN_CTX_free(ctx);
|
|
if (kinv != NULL)
|
|
BN_clear_free(kinv);
|
|
if (order != NULL)
|
|
BN_clear_free(order);
|
|
if (tmp_point != NULL)
|
|
EC_POINT_free(tmp_point);
|
|
if (X) BN_clear_free(X);
|
|
BN_clear_free(&k);
|
|
return(ret);
|
|
}
|
|
|
|
|
|
static ECDSA_SIG *ecdsa_do_sign(const unsigned char *dgst, int dgst_len,
|
|
EC_KEY *eckey)
|
|
{
|
|
BIGNUM *kinv=NULL,*r=NULL,*s=NULL,*m=NULL,*tmp=NULL,*order=NULL;
|
|
BIGNUM xr;
|
|
BN_CTX *ctx=NULL;
|
|
ECDSA_SIG *ret=NULL;
|
|
ECDSA_DATA *ecdsa;
|
|
|
|
ecdsa = ecdsa_check(eckey);
|
|
|
|
if (!eckey || !eckey->group || !eckey->pub_key || !eckey->priv_key
|
|
|| !ecdsa)
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_PASSED_NULL_PARAMETER);
|
|
goto err;
|
|
}
|
|
BN_init(&xr);
|
|
|
|
if ((ctx = BN_CTX_new()) == NULL || (order = BN_new()) == NULL ||
|
|
(tmp = BN_new()) == NULL || (m = BN_new()) == NULL ||
|
|
(s = BN_new()) == NULL )
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_MALLOC_FAILURE);
|
|
goto err;
|
|
}
|
|
|
|
if (!EC_GROUP_get_order(eckey->group,order,ctx))
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_EC_LIB);
|
|
goto err;
|
|
}
|
|
if (dgst_len > BN_num_bytes(order))
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_DO_SIGN,
|
|
ECDSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE);
|
|
goto err;
|
|
}
|
|
|
|
if (BN_bin2bn(dgst,dgst_len,m) == NULL)
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_BN_LIB);
|
|
goto err;
|
|
}
|
|
do
|
|
{
|
|
if (ecdsa->kinv == NULL || ecdsa->r == NULL)
|
|
{
|
|
if (!ECDSA_sign_setup(eckey,ctx,&kinv,&r))
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_DO_SIGN,
|
|
ERR_R_ECDSA_LIB);
|
|
goto err;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
kinv = ecdsa->kinv;
|
|
ecdsa->kinv = NULL;
|
|
r = ecdsa->r;
|
|
ecdsa->r = NULL;
|
|
}
|
|
|
|
if (!BN_mod_mul(tmp,eckey->priv_key,r,order,ctx))
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_BN_LIB);
|
|
goto err;
|
|
}
|
|
if (!BN_add(s,tmp,m))
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_BN_LIB);
|
|
goto err;
|
|
}
|
|
if (BN_cmp(s,order) > 0)
|
|
BN_sub(s,s,order);
|
|
if (!BN_mod_mul(s,s,kinv,order,ctx))
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_BN_LIB);
|
|
goto err;
|
|
}
|
|
}
|
|
while (BN_is_zero(s));
|
|
|
|
if ((ret = ECDSA_SIG_new()) == NULL)
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_MALLOC_FAILURE);
|
|
goto err;
|
|
}
|
|
if (BN_copy(ret->r, r) == NULL || BN_copy(ret->s, s) == NULL)
|
|
{
|
|
ECDSA_SIG_free(ret);
|
|
ret = NULL;
|
|
ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_BN_LIB);
|
|
}
|
|
|
|
err:
|
|
if (r)
|
|
BN_clear_free(r);
|
|
if (s)
|
|
BN_clear_free(s);
|
|
if (ctx)
|
|
BN_CTX_free(ctx);
|
|
if (m)
|
|
BN_clear_free(m);
|
|
if (tmp)
|
|
BN_clear_free(tmp);
|
|
if (order)
|
|
BN_clear_free(order);
|
|
if (kinv)
|
|
BN_clear_free(kinv);
|
|
return(ret);
|
|
}
|
|
|
|
static int ecdsa_do_verify(const unsigned char *dgst, int dgst_len,
|
|
ECDSA_SIG *sig, EC_KEY *eckey)
|
|
{
|
|
BN_CTX *ctx;
|
|
BIGNUM *order=NULL,*u1=NULL,*u2=NULL,*m=NULL,*X=NULL;
|
|
EC_POINT *point=NULL;
|
|
int ret = -1;
|
|
if (!eckey || !eckey->group || !eckey->pub_key || !sig)
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ECDSA_R_MISSING_PARAMETERS);
|
|
return -1;
|
|
}
|
|
|
|
if ((ctx = BN_CTX_new()) == NULL || (order = BN_new()) == NULL ||
|
|
(u1 = BN_new()) == NULL || (u2 = BN_new()) == NULL ||
|
|
(m = BN_new()) == NULL || (X = BN_new()) == NULL)
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_MALLOC_FAILURE);
|
|
goto err;
|
|
}
|
|
if (!EC_GROUP_get_order(eckey->group, order, ctx))
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB);
|
|
goto err;
|
|
}
|
|
|
|
if (BN_is_zero(sig->r) || BN_get_sign(sig->r) ||
|
|
BN_ucmp(sig->r, order) >= 0)
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ECDSA_R_BAD_SIGNATURE);
|
|
ret = 0;
|
|
goto err;
|
|
}
|
|
if (BN_is_zero(sig->s) || BN_get_sign(sig->s) ||
|
|
BN_ucmp(sig->s, order) >= 0)
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ECDSA_R_BAD_SIGNATURE);
|
|
ret = 0;
|
|
goto err;
|
|
}
|
|
|
|
/* calculate tmp1 = inv(S) mod order */
|
|
if ((BN_mod_inverse(u2,sig->s,order,ctx)) == NULL)
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB);
|
|
goto err;
|
|
}
|
|
/* digest -> m */
|
|
if (BN_bin2bn(dgst,dgst_len,m) == NULL)
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB);
|
|
goto err;
|
|
}
|
|
/* u1 = m * tmp mod order */
|
|
if (!BN_mod_mul(u1,m,u2,order,ctx))
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB);
|
|
goto err;
|
|
}
|
|
/* u2 = r * w mod q */
|
|
if (!BN_mod_mul(u2,sig->r,u2,order,ctx))
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB);
|
|
goto err;
|
|
}
|
|
|
|
if ((point = EC_POINT_new(eckey->group)) == NULL)
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_MALLOC_FAILURE);
|
|
goto err;
|
|
}
|
|
if (!EC_POINT_mul(eckey->group, point, u1, eckey->pub_key, u2, ctx))
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_EC_LIB);
|
|
goto err;
|
|
}
|
|
if (EC_METHOD_get_field_type(EC_GROUP_method_of(eckey->group))
|
|
== NID_X9_62_prime_field)
|
|
{
|
|
if (!EC_POINT_get_affine_coordinates_GFp(eckey->group,
|
|
point, X, NULL, ctx))
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB);
|
|
goto err;
|
|
}
|
|
}
|
|
else /* NID_X9_62_characteristic_two_field */
|
|
{
|
|
if (!EC_POINT_get_affine_coordinates_GF2m(eckey->group,
|
|
point, X, NULL, ctx))
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB);
|
|
goto err;
|
|
}
|
|
}
|
|
|
|
if (!BN_nnmod(u1,X,order,ctx))
|
|
{
|
|
ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB);
|
|
goto err;
|
|
}
|
|
|
|
/* is now in u1. If the signature is correct, it will be
|
|
* equal to R. */
|
|
ret = (BN_ucmp(u1,sig->r) == 0);
|
|
|
|
err:
|
|
if (ctx)
|
|
BN_CTX_free(ctx);
|
|
if (u1)
|
|
BN_clear_free(u1);
|
|
if (u2)
|
|
BN_clear_free(u2);
|
|
if (m)
|
|
BN_clear_free(m);
|
|
if (X)
|
|
BN_clear_free(X);
|
|
if (order)
|
|
BN_clear_free(order);
|
|
if (point)
|
|
EC_POINT_free(point);
|
|
return(ret);
|
|
}
|