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/*
* Copyright (C) 2003, 2004, 2005, 2007 Free Software Foundation
*
* Author: Nikos Mavrogiannopoulos
*
* This file is part of GNUTLS.
*
* The GNUTLS library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License
* as published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
* USA
*
*/
#include <gnutls_int.h>
#include <gnutls_errors.h>
#include <gnutls_global.h>
#include <libtasn1.h>
#include <gnutls_datum.h>
#include "common.h"
#include "x509.h"
#include <gnutls_num.h>
#include "mpi.h"
/*
* some x509 certificate parsing functions that relate to MPI parameter
* extraction. This reads the BIT STRING subjectPublicKey.
* Returns 2 parameters (m,e).
*/
int
MHD__gnutls_x509_read_rsa_params (opaque * der, int dersize, mpi_t * params)
{
int result;
ASN1_TYPE spk = ASN1_TYPE_EMPTY;
if ((result =
MHD__asn1_create_element (MHD__gnutls_getMHD__gnutls_asn (),
"GNUTLS.RSAPublicKey",
&spk)) != ASN1_SUCCESS)
{
MHD_gnutls_assert ();
return MHD_gtls_asn2err (result);
}
result = MHD__asn1_der_decoding (&spk, der, dersize, NULL);
if (result != ASN1_SUCCESS)
{
MHD_gnutls_assert ();
MHD__asn1_delete_structure (&spk);
return MHD_gtls_asn2err (result);
}
if ((result = MHD__gnutls_x509_read_int (spk, "modulus", ¶ms[0])) < 0)
{
MHD_gnutls_assert ();
MHD__asn1_delete_structure (&spk);
return GNUTLS_E_ASN1_GENERIC_ERROR;
}
if ((result =
MHD__gnutls_x509_read_int (spk, "publicExponent", ¶ms[1])) < 0)
{
MHD_gnutls_assert ();
MHD_gtls_mpi_release (¶ms[0]);
MHD__asn1_delete_structure (&spk);
return GNUTLS_E_ASN1_GENERIC_ERROR;
}
MHD__asn1_delete_structure (&spk);
return 0;
}
/* Extracts DSA and RSA parameters from a certificate.
*/
int
MHD__gnutls_x509_crt_get_mpis (MHD_gnutls_x509_crt_t cert,
mpi_t * params, int *params_size)
{
int result;
int pk_algorithm;
MHD_gnutls_datum_t tmp = { NULL, 0 };
/* Read the algorithm's OID
*/
pk_algorithm = MHD_gnutls_x509_crt_get_pk_algorithm (cert, NULL);
/* Read the algorithm's parameters
*/
result
= MHD__gnutls_x509_read_value (cert->cert,
"tbsCertificate.subjectPublicKeyInfo.subjectPublicKey",
&tmp, 2);
if (result < 0)
{
MHD_gnutls_assert ();
return result;
}
switch (pk_algorithm)
{
case MHD_GNUTLS_PK_RSA:
/* params[0] is the modulus,
* params[1] is the exponent
*/
if (*params_size < RSA_PUBLIC_PARAMS)
{
MHD_gnutls_assert ();
/* internal error. Increase the mpi_ts in params */
result = GNUTLS_E_INTERNAL_ERROR;
goto error;
}
if ((result =
MHD__gnutls_x509_read_rsa_params (tmp.data, tmp.size, params)) < 0)
{
MHD_gnutls_assert ();
goto error;
}
*params_size = RSA_PUBLIC_PARAMS;
break;
default:
/* other types like DH
* currently not supported
*/
MHD_gnutls_assert ();
result = GNUTLS_E_X509_CERTIFICATE_ERROR;
goto error;
}
result = 0;
error:MHD__gnutls_free_datum (&tmp);
return result;
}
/*
* some x509 certificate functions that relate to MPI parameter
* setting. This writes the BIT STRING subjectPublicKey.
* Needs 2 parameters (m,e).
*
* Allocates the space used to store the DER data.
*/
int
MHD__gnutls_x509_write_rsa_params (mpi_t * params,
int params_size, MHD_gnutls_datum_t * der)
{
int result;
ASN1_TYPE spk = ASN1_TYPE_EMPTY;
der->data = NULL;
der->size = 0;
if (params_size < 2)
{
MHD_gnutls_assert ();
result = GNUTLS_E_INVALID_REQUEST;
goto cleanup;
}
if ((result =
MHD__asn1_create_element (MHD__gnutls_getMHD__gnutls_asn (),
"GNUTLS.RSAPublicKey",
&spk)) != ASN1_SUCCESS)
{
MHD_gnutls_assert ();
return MHD_gtls_asn2err (result);
}
result = MHD__gnutls_x509_write_int (spk, "modulus", params[0], 0);
if (result < 0)
{
MHD_gnutls_assert ();
goto cleanup;
}
result = MHD__gnutls_x509_write_int (spk, "publicExponent", params[1], 0);
if (result < 0)
{
MHD_gnutls_assert ();
goto cleanup;
}
result = MHD__gnutls_x509_der_encode (spk, "", der, 0);
if (result < 0)
{
MHD_gnutls_assert ();
goto cleanup;
}
MHD__asn1_delete_structure (&spk);
return 0;
cleanup:MHD__asn1_delete_structure (&spk);
return result;
}
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