mbedtls/library/ecdh.c

308 lines
8.6 KiB
C
Raw Normal View History

2013-01-26 14:30:46 +00:00
/*
* Elliptic curve Diffie-Hellman
*
2015-07-27 09:11:48 +00:00
* Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
Update license headers to Apache-2.0 OR GPL-2.0-or-later This will allow us to ship the LTS branches in a single archive This commit was generated using the following script: # ======================== #!/bin/sh header1='\ * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later\ *\ * This file is provided under the Apache License 2.0, or the\ * GNU General Public License v2.0 or later.\ *\ * **********\ * Apache License 2.0:\ *\ * Licensed under the Apache License, Version 2.0 (the "License"); you may\ * not use this file except in compliance with the License.\ * You may obtain a copy of the License at\ *\ * http://www.apache.org/licenses/LICENSE-2.0\ *\ * Unless required by applicable law or agreed to in writing, software\ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT\ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\ * See the License for the specific language governing permissions and\ * limitations under the License.\ *\ * **********\ *\ * **********\ * GNU General Public License v2.0 or later:\ *\ * This program is free software; you can redistribute it and/or modify\ * it under the terms of the GNU General Public License as published by\ * the Free Software Foundation; either version 2 of the License, or\ * (at your option) any later version.\ *\ * This program 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 General Public License for more details.\ *\ * You should have received a copy of the GNU General Public License along\ * with this program; if not, write to the Free Software Foundation, Inc.,\ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.\ *\ * **********' find -path './.git' -prune -o '(' -name '*.c' -o -name '*.cpp' -o -name '*.fmt' -o -name '*.h' ')' -print | xargs sed -i " # Normalize the first line of the copyright headers (no text on the first line of a block comment) /^\/\*.*Copyright.*Arm/I s/\/\*/&\n */ # Insert new copyright header /SPDX-License-Identifier/ i\ $header1 # Delete old copyright header /SPDX-License-Identifier/,$ { # Delete lines until the one preceding the mbedtls declaration N 1,/This file is part of/ { /This file is part of/! D } } " # Format copyright header for inclusion into scripts header2=$(echo "$header1" | sed 's/^\\\? \* \?/#/') find -path './.git' -prune -o '(' -name '*.gdb' -o -name '*.pl' -o -name '*.py' -o -name '*.sh' ')' -print | xargs sed -i " # Insert new copyright header /SPDX-License-Identifier/ i\ $header2 # Delete old copyright header /SPDX-License-Identifier/,$ { # Delete lines until the one preceding the mbedtls declaration N 1,/This file is part of/ { /This file is part of/! D } } " # ======================== Signed-off-by: Bence Szépkúti <bence.szepkuti@arm.com>
2020-06-05 11:02:18 +00:00
* SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
*
* This file is provided under the Apache License 2.0, or the
* GNU General Public License v2.0 or later.
*
* **********
* Apache License 2.0:
2013-01-26 14:30:46 +00:00
*
2015-09-04 12:21:07 +00:00
* Licensed under the Apache License, Version 2.0 (the "License"); you may
* not use this file except in compliance with the License.
* You may obtain a copy of the License at
2013-01-26 14:30:46 +00:00
*
2015-09-04 12:21:07 +00:00
* http://www.apache.org/licenses/LICENSE-2.0
2013-01-26 14:30:46 +00:00
*
2015-09-04 12:21:07 +00:00
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
2013-01-26 14:30:46 +00:00
*
Update license headers to Apache-2.0 OR GPL-2.0-or-later This will allow us to ship the LTS branches in a single archive This commit was generated using the following script: # ======================== #!/bin/sh header1='\ * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later\ *\ * This file is provided under the Apache License 2.0, or the\ * GNU General Public License v2.0 or later.\ *\ * **********\ * Apache License 2.0:\ *\ * Licensed under the Apache License, Version 2.0 (the "License"); you may\ * not use this file except in compliance with the License.\ * You may obtain a copy of the License at\ *\ * http://www.apache.org/licenses/LICENSE-2.0\ *\ * Unless required by applicable law or agreed to in writing, software\ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT\ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\ * See the License for the specific language governing permissions and\ * limitations under the License.\ *\ * **********\ *\ * **********\ * GNU General Public License v2.0 or later:\ *\ * This program is free software; you can redistribute it and/or modify\ * it under the terms of the GNU General Public License as published by\ * the Free Software Foundation; either version 2 of the License, or\ * (at your option) any later version.\ *\ * This program 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 General Public License for more details.\ *\ * You should have received a copy of the GNU General Public License along\ * with this program; if not, write to the Free Software Foundation, Inc.,\ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.\ *\ * **********' find -path './.git' -prune -o '(' -name '*.c' -o -name '*.cpp' -o -name '*.fmt' -o -name '*.h' ')' -print | xargs sed -i " # Normalize the first line of the copyright headers (no text on the first line of a block comment) /^\/\*.*Copyright.*Arm/I s/\/\*/&\n */ # Insert new copyright header /SPDX-License-Identifier/ i\ $header1 # Delete old copyright header /SPDX-License-Identifier/,$ { # Delete lines until the one preceding the mbedtls declaration N 1,/This file is part of/ { /This file is part of/! D } } " # Format copyright header for inclusion into scripts header2=$(echo "$header1" | sed 's/^\\\? \* \?/#/') find -path './.git' -prune -o '(' -name '*.gdb' -o -name '*.pl' -o -name '*.py' -o -name '*.sh' ')' -print | xargs sed -i " # Insert new copyright header /SPDX-License-Identifier/ i\ $header2 # Delete old copyright header /SPDX-License-Identifier/,$ { # Delete lines until the one preceding the mbedtls declaration N 1,/This file is part of/ { /This file is part of/! D } } " # ======================== Signed-off-by: Bence Szépkúti <bence.szepkuti@arm.com>
2020-06-05 11:02:18 +00:00
* **********
*
* **********
* GNU General Public License v2.0 or later:
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* **********
*
2015-09-04 12:21:07 +00:00
* This file is part of mbed TLS (https://tls.mbed.org)
2013-01-26 14:30:46 +00:00
*/
/*
* References:
*
* SEC1 http://www.secg.org/index.php?action=secg,docs_secg
2013-02-10 13:21:04 +00:00
* RFC 4492
2013-01-26 14:30:46 +00:00
*/
#if !defined(MBEDTLS_CONFIG_FILE)
2015-03-09 17:05:11 +00:00
#include "mbedtls/config.h"
#else
#include MBEDTLS_CONFIG_FILE
#endif
2013-01-26 14:30:46 +00:00
#if defined(MBEDTLS_ECDH_C)
2013-01-26 14:30:46 +00:00
2015-03-09 17:05:11 +00:00
#include "mbedtls/ecdh.h"
2013-01-26 14:30:46 +00:00
#include <string.h>
#if !defined(MBEDTLS_ECDH_GEN_PUBLIC_ALT)
2013-01-26 15:05:22 +00:00
/*
* Generate public key: simple wrapper around mbedtls_ecp_gen_keypair
2013-01-26 15:05:22 +00:00
*/
int mbedtls_ecdh_gen_public( mbedtls_ecp_group *grp, mbedtls_mpi *d, mbedtls_ecp_point *Q,
2013-01-26 15:05:22 +00:00
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng )
{
return mbedtls_ecp_gen_keypair( grp, d, Q, f_rng, p_rng );
2013-01-26 15:05:22 +00:00
}
#endif /* MBEDTLS_ECDH_GEN_PUBLIC_ALT */
2013-01-26 15:05:22 +00:00
#if !defined(MBEDTLS_ECDH_COMPUTE_SHARED_ALT)
2013-01-26 15:05:22 +00:00
/*
* Compute shared secret (SEC1 3.3.1)
*/
int mbedtls_ecdh_compute_shared( mbedtls_ecp_group *grp, mbedtls_mpi *z,
const mbedtls_ecp_point *Q, const mbedtls_mpi *d,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng )
2013-01-26 15:05:22 +00:00
{
int ret;
mbedtls_ecp_point P;
2013-01-26 15:05:22 +00:00
mbedtls_ecp_point_init( &P );
2013-01-26 15:05:22 +00:00
/*
* Make sure Q is a valid pubkey before using it
*/
MBEDTLS_MPI_CHK( mbedtls_ecp_check_pubkey( grp, Q ) );
2013-01-26 15:05:22 +00:00
MBEDTLS_MPI_CHK( mbedtls_ecp_mul( grp, &P, d, Q, f_rng, p_rng ) );
2013-01-26 15:05:22 +00:00
if( mbedtls_ecp_is_zero( &P ) )
{
ret = MBEDTLS_ERR_ECP_BAD_INPUT_DATA;
goto cleanup;
}
2013-01-26 15:05:22 +00:00
MBEDTLS_MPI_CHK( mbedtls_mpi_copy( z, &P.X ) );
2013-01-26 15:05:22 +00:00
cleanup:
mbedtls_ecp_point_free( &P );
2013-01-26 15:05:22 +00:00
return( ret );
}
#endif /* MBEDTLS_ECDH_COMPUTE_SHARED_ALT */
2013-02-10 13:21:04 +00:00
/*
* Initialize context
*/
void mbedtls_ecdh_init( mbedtls_ecdh_context *ctx )
2013-02-10 13:21:04 +00:00
{
memset( ctx, 0, sizeof( mbedtls_ecdh_context ) );
2013-02-10 13:21:04 +00:00
}
/*
* Free context
*/
void mbedtls_ecdh_free( mbedtls_ecdh_context *ctx )
2013-02-10 13:21:04 +00:00
{
if( ctx == NULL )
return;
mbedtls_ecp_group_free( &ctx->grp );
mbedtls_ecp_point_free( &ctx->Q );
mbedtls_ecp_point_free( &ctx->Qp );
mbedtls_ecp_point_free( &ctx->Vi );
mbedtls_ecp_point_free( &ctx->Vf );
mbedtls_mpi_free( &ctx->d );
mbedtls_mpi_free( &ctx->z );
mbedtls_mpi_free( &ctx->_d );
2013-02-10 13:21:04 +00:00
}
/*
2013-02-11 19:28:55 +00:00
* Setup and write the ServerKeyExhange parameters (RFC 4492)
* struct {
* ECParameters curve_params;
* ECPoint public;
* } ServerECDHParams;
*/
int mbedtls_ecdh_make_params( mbedtls_ecdh_context *ctx, size_t *olen,
2013-02-11 19:28:55 +00:00
unsigned char *buf, size_t blen,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng )
{
int ret;
size_t grp_len, pt_len;
2013-02-11 21:12:39 +00:00
if( ctx == NULL || ctx->grp.pbits == 0 )
return( MBEDTLS_ERR_ECP_BAD_INPUT_DATA );
2013-02-11 21:12:39 +00:00
if( ( ret = mbedtls_ecdh_gen_public( &ctx->grp, &ctx->d, &ctx->Q, f_rng, p_rng ) )
!= 0 )
return( ret );
if( ( ret = mbedtls_ecp_tls_write_group( &ctx->grp, &grp_len, buf, blen ) )
!= 0 )
return( ret );
buf += grp_len;
blen -= grp_len;
if( ( ret = mbedtls_ecp_tls_write_point( &ctx->grp, &ctx->Q, ctx->point_format,
&pt_len, buf, blen ) ) != 0 )
return( ret );
*olen = grp_len + pt_len;
2014-06-17 12:06:49 +00:00
return( 0 );
}
2013-02-11 19:28:55 +00:00
/*
* Read the ServerKeyExhange parameters (RFC 4492)
* struct {
* ECParameters curve_params;
* ECPoint public;
* } ServerECDHParams;
*/
int mbedtls_ecdh_read_params( mbedtls_ecdh_context *ctx,
2013-02-11 19:28:55 +00:00
const unsigned char **buf, const unsigned char *end )
{
int ret;
if( ( ret = mbedtls_ecp_tls_read_group( &ctx->grp, buf, end - *buf ) ) != 0 )
2013-02-11 19:28:55 +00:00
return( ret );
if( ( ret = mbedtls_ecp_tls_read_point( &ctx->grp, &ctx->Qp, buf, end - *buf ) )
2013-02-11 19:28:55 +00:00
!= 0 )
return( ret );
2014-06-17 12:06:49 +00:00
return( 0 );
2013-02-11 19:28:55 +00:00
}
2013-01-26 14:30:46 +00:00
/*
* Get parameters from a keypair
*/
int mbedtls_ecdh_get_params( mbedtls_ecdh_context *ctx, const mbedtls_ecp_keypair *key,
mbedtls_ecdh_side side )
{
int ret;
if( ctx->grp.id == MBEDTLS_ECP_DP_NONE )
{
/* This is the first call to get_params(). Copy the group information
* into the context. */
if( ( ret = mbedtls_ecp_group_copy( &ctx->grp, &key->grp ) ) != 0 )
return( ret );
}
else
{
/* This is not the first call to get_params(). Check that the group
* is the same as the first time. */
if( ctx->grp.id != key->grp.id )
return( MBEDTLS_ERR_ECP_BAD_INPUT_DATA );
}
/* If it's not our key, just import the public part as Qp */
if( side == MBEDTLS_ECDH_THEIRS )
return( mbedtls_ecp_copy( &ctx->Qp, &key->Q ) );
/* Our key: import public (as Q) and private parts */
if( side != MBEDTLS_ECDH_OURS )
return( MBEDTLS_ERR_ECP_BAD_INPUT_DATA );
if( ( ret = mbedtls_ecp_copy( &ctx->Q, &key->Q ) ) != 0 ||
( ret = mbedtls_mpi_copy( &ctx->d, &key->d ) ) != 0 )
return( ret );
return( 0 );
}
2013-02-11 20:51:45 +00:00
/*
* Setup and export the client public value
*/
int mbedtls_ecdh_make_public( mbedtls_ecdh_context *ctx, size_t *olen,
2013-02-11 20:51:45 +00:00
unsigned char *buf, size_t blen,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng )
{
int ret;
2013-02-11 21:12:39 +00:00
if( ctx == NULL || ctx->grp.pbits == 0 )
return( MBEDTLS_ERR_ECP_BAD_INPUT_DATA );
2013-02-11 21:12:39 +00:00
if( ( ret = mbedtls_ecdh_gen_public( &ctx->grp, &ctx->d, &ctx->Q, f_rng, p_rng ) )
2013-02-11 20:51:45 +00:00
!= 0 )
return( ret );
return mbedtls_ecp_tls_write_point( &ctx->grp, &ctx->Q, ctx->point_format,
2013-02-11 20:51:45 +00:00
olen, buf, blen );
}
/*
* Parse and import the client's public value
*/
int mbedtls_ecdh_read_public( mbedtls_ecdh_context *ctx,
2013-02-11 20:51:45 +00:00
const unsigned char *buf, size_t blen )
{
int ret;
const unsigned char *p = buf;
2013-02-11 21:12:39 +00:00
if( ctx == NULL )
return( MBEDTLS_ERR_ECP_BAD_INPUT_DATA );
2013-02-11 21:12:39 +00:00
if( ( ret = mbedtls_ecp_tls_read_point( &ctx->grp, &ctx->Qp, &p, blen ) ) != 0 )
return( ret );
if( (size_t)( p - buf ) != blen )
return( MBEDTLS_ERR_ECP_BAD_INPUT_DATA );
return( 0 );
2013-02-11 20:51:45 +00:00
}
2013-02-11 21:05:42 +00:00
/*
* Derive and export the shared secret
*/
int mbedtls_ecdh_calc_secret( mbedtls_ecdh_context *ctx, size_t *olen,
unsigned char *buf, size_t blen,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng )
2013-02-11 21:05:42 +00:00
{
int ret;
2013-02-11 21:12:39 +00:00
if( ctx == NULL )
return( MBEDTLS_ERR_ECP_BAD_INPUT_DATA );
2013-02-11 21:12:39 +00:00
if( ( ret = mbedtls_ecdh_compute_shared( &ctx->grp, &ctx->z, &ctx->Qp, &ctx->d,
f_rng, p_rng ) ) != 0 )
{
2013-02-11 21:05:42 +00:00
return( ret );
}
2013-02-11 21:05:42 +00:00
if( mbedtls_mpi_size( &ctx->z ) > blen )
return( MBEDTLS_ERR_ECP_BAD_INPUT_DATA );
*olen = ctx->grp.pbits / 8 + ( ( ctx->grp.pbits % 8 ) != 0 );
return mbedtls_mpi_write_binary( &ctx->z, buf, *olen );
2013-02-11 21:05:42 +00:00
}
#endif /* MBEDTLS_ECDH_C */