mbedtls/library/psa_crypto_ecp.c
Ronald Cron cfc3c7b593 psa: Remove test code in the library
The current testing of the PSA configuration is
based on test code located in the library itself.

Remove this code as we are moving to using a
test library instead.

Signed-off-by: Ronald Cron <ronald.cron@arm.com>
2021-11-30 14:49:19 +01:00

473 lines
17 KiB
C

/*
* PSA ECP layer on top of Mbed TLS crypto
*/
/*
* Copyright The Mbed TLS Contributors
* SPDX-License-Identifier: Apache-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.
*/
#include "common.h"
#if defined(MBEDTLS_PSA_CRYPTO_C)
#include <psa/crypto.h>
#include "psa_crypto_core.h"
#include "psa_crypto_ecp.h"
#include "psa_crypto_random_impl.h"
#include "psa_crypto_hash.h"
#include <stdlib.h>
#include <string.h>
#include "mbedtls/platform.h"
#if !defined(MBEDTLS_PLATFORM_C)
#define mbedtls_calloc calloc
#define mbedtls_free free
#endif
#include <mbedtls/ecdsa.h>
#include <mbedtls/ecp.h>
#include <mbedtls/error.h>
#if defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_ECC_KEY_PAIR) || \
defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_ECC_PUBLIC_KEY) || \
defined(MBEDTLS_PSA_BUILTIN_ALG_ECDSA) || \
defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA) || \
defined(MBEDTLS_PSA_BUILTIN_ALG_ECDH)
psa_status_t mbedtls_psa_ecp_load_representation(
psa_key_type_t type, size_t curve_bits,
const uint8_t *data, size_t data_length,
mbedtls_ecp_keypair **p_ecp )
{
mbedtls_ecp_group_id grp_id = MBEDTLS_ECP_DP_NONE;
psa_status_t status;
mbedtls_ecp_keypair *ecp = NULL;
size_t curve_bytes = data_length;
int explicit_bits = ( curve_bits != 0 );
if( PSA_KEY_TYPE_IS_PUBLIC_KEY( type ) &&
PSA_KEY_TYPE_ECC_GET_FAMILY( type ) != PSA_ECC_FAMILY_MONTGOMERY )
{
/* A Weierstrass public key is represented as:
* - The byte 0x04;
* - `x_P` as a `ceiling(m/8)`-byte string, big-endian;
* - `y_P` as a `ceiling(m/8)`-byte string, big-endian.
* So its data length is 2m+1 where m is the curve size in bits.
*/
if( ( data_length & 1 ) == 0 )
return( PSA_ERROR_INVALID_ARGUMENT );
curve_bytes = data_length / 2;
/* Montgomery public keys are represented in compressed format, meaning
* their curve_bytes is equal to the amount of input. */
/* Private keys are represented in uncompressed private random integer
* format, meaning their curve_bytes is equal to the amount of input. */
}
if( explicit_bits )
{
/* With an explicit bit-size, the data must have the matching length. */
if( curve_bytes != PSA_BITS_TO_BYTES( curve_bits ) )
return( PSA_ERROR_INVALID_ARGUMENT );
}
else
{
/* We need to infer the bit-size from the data. Since the only
* information we have is the length in bytes, the value of curve_bits
* at this stage is rounded up to the nearest multiple of 8. */
curve_bits = PSA_BYTES_TO_BITS( curve_bytes );
}
/* Allocate and initialize a key representation. */
ecp = mbedtls_calloc( 1, sizeof( mbedtls_ecp_keypair ) );
if( ecp == NULL )
return( PSA_ERROR_INSUFFICIENT_MEMORY );
mbedtls_ecp_keypair_init( ecp );
/* Load the group. */
grp_id = mbedtls_ecc_group_of_psa( PSA_KEY_TYPE_ECC_GET_FAMILY( type ),
curve_bits, !explicit_bits );
if( grp_id == MBEDTLS_ECP_DP_NONE )
{
/* We can't distinguish between a nonsensical family/size combination
* (which would warrant PSA_ERROR_INVALID_ARGUMENT) and a
* well-regarded curve that Mbed TLS just doesn't know about (which
* would warrant PSA_ERROR_NOT_SUPPORTED). For uniformity with how
* curves that Mbed TLS knows about but for which support is disabled
* at build time, return NOT_SUPPORTED. */
status = PSA_ERROR_NOT_SUPPORTED;
goto exit;
}
status = mbedtls_to_psa_error(
mbedtls_ecp_group_load( &ecp->grp, grp_id ) );
if( status != PSA_SUCCESS )
goto exit;
/* Load the key material. */
if( PSA_KEY_TYPE_IS_PUBLIC_KEY( type ) )
{
/* Load the public value. */
status = mbedtls_to_psa_error(
mbedtls_ecp_point_read_binary( &ecp->grp, &ecp->Q,
data,
data_length ) );
if( status != PSA_SUCCESS )
goto exit;
/* Check that the point is on the curve. */
status = mbedtls_to_psa_error(
mbedtls_ecp_check_pubkey( &ecp->grp, &ecp->Q ) );
if( status != PSA_SUCCESS )
goto exit;
}
else
{
/* Load and validate the secret value. */
status = mbedtls_to_psa_error(
mbedtls_ecp_read_key( ecp->grp.id,
ecp,
data,
data_length ) );
if( status != PSA_SUCCESS )
goto exit;
}
*p_ecp = ecp;
exit:
if( status != PSA_SUCCESS )
{
mbedtls_ecp_keypair_free( ecp );
mbedtls_free( ecp );
}
return( status );
}
#endif /* defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_ECC_KEY_PAIR) ||
* defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_ECC_PUBLIC_KEY) ||
* defined(MBEDTLS_PSA_BUILTIN_ALG_ECDSA) ||
* defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA) ||
* defined(MBEDTLS_PSA_BUILTIN_ALG_ECDH) */
#if defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_ECC_KEY_PAIR) || \
defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_ECC_PUBLIC_KEY)
psa_status_t mbedtls_psa_ecp_import_key(
const psa_key_attributes_t *attributes,
const uint8_t *data, size_t data_length,
uint8_t *key_buffer, size_t key_buffer_size,
size_t *key_buffer_length, size_t *bits )
{
psa_status_t status;
mbedtls_ecp_keypair *ecp = NULL;
/* Parse input */
status = mbedtls_psa_ecp_load_representation( attributes->core.type,
attributes->core.bits,
data,
data_length,
&ecp );
if( status != PSA_SUCCESS )
goto exit;
if( PSA_KEY_TYPE_ECC_GET_FAMILY( attributes->core.type ) ==
PSA_ECC_FAMILY_MONTGOMERY )
*bits = ecp->grp.nbits + 1;
else
*bits = ecp->grp.nbits;
/* Re-export the data to PSA export format. There is currently no support
* for other input formats then the export format, so this is a 1-1
* copy operation. */
status = mbedtls_psa_ecp_export_key( attributes->core.type,
ecp,
key_buffer,
key_buffer_size,
key_buffer_length );
exit:
/* Always free the PK object (will also free contained ECP context) */
mbedtls_ecp_keypair_free( ecp );
mbedtls_free( ecp );
return( status );
}
psa_status_t mbedtls_psa_ecp_export_key( psa_key_type_t type,
mbedtls_ecp_keypair *ecp,
uint8_t *data,
size_t data_size,
size_t *data_length )
{
psa_status_t status;
if( PSA_KEY_TYPE_IS_PUBLIC_KEY( type ) )
{
/* Check whether the public part is loaded */
if( mbedtls_ecp_is_zero( &ecp->Q ) )
{
/* Calculate the public key */
status = mbedtls_to_psa_error(
mbedtls_ecp_mul( &ecp->grp, &ecp->Q, &ecp->d, &ecp->grp.G,
mbedtls_psa_get_random,
MBEDTLS_PSA_RANDOM_STATE ) );
if( status != PSA_SUCCESS )
return( status );
}
status = mbedtls_to_psa_error(
mbedtls_ecp_point_write_binary( &ecp->grp, &ecp->Q,
MBEDTLS_ECP_PF_UNCOMPRESSED,
data_length,
data,
data_size ) );
if( status != PSA_SUCCESS )
memset( data, 0, data_size );
return( status );
}
else
{
if( data_size < PSA_BITS_TO_BYTES( ecp->grp.nbits ) )
return( PSA_ERROR_BUFFER_TOO_SMALL );
status = mbedtls_to_psa_error(
mbedtls_ecp_write_key( ecp,
data,
PSA_BITS_TO_BYTES( ecp->grp.nbits ) ) );
if( status == PSA_SUCCESS )
*data_length = PSA_BITS_TO_BYTES( ecp->grp.nbits );
else
memset( data, 0, data_size );
return( status );
}
}
psa_status_t mbedtls_psa_ecp_export_public_key(
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer, size_t key_buffer_size,
uint8_t *data, size_t data_size, size_t *data_length )
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
mbedtls_ecp_keypair *ecp = NULL;
status = mbedtls_psa_ecp_load_representation(
attributes->core.type, attributes->core.bits,
key_buffer, key_buffer_size, &ecp );
if( status != PSA_SUCCESS )
return( status );
status = mbedtls_psa_ecp_export_key(
PSA_KEY_TYPE_ECC_PUBLIC_KEY(
PSA_KEY_TYPE_ECC_GET_FAMILY( attributes->core.type ) ),
ecp, data, data_size, data_length );
mbedtls_ecp_keypair_free( ecp );
mbedtls_free( ecp );
return( status );
}
#endif /* defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_ECC_KEY_PAIR) ||
* defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_ECC_PUBLIC_KEY) */
#if defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_ECC_KEY_PAIR)
psa_status_t mbedtls_psa_ecp_generate_key(
const psa_key_attributes_t *attributes,
uint8_t *key_buffer, size_t key_buffer_size, size_t *key_buffer_length )
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
psa_ecc_family_t curve = PSA_KEY_TYPE_ECC_GET_FAMILY(
attributes->core.type );
mbedtls_ecp_group_id grp_id =
mbedtls_ecc_group_of_psa( curve, attributes->core.bits, 0 );
const mbedtls_ecp_curve_info *curve_info =
mbedtls_ecp_curve_info_from_grp_id( grp_id );
mbedtls_ecp_keypair ecp;
if( attributes->domain_parameters_size != 0 )
return( PSA_ERROR_NOT_SUPPORTED );
if( grp_id == MBEDTLS_ECP_DP_NONE || curve_info == NULL )
return( PSA_ERROR_NOT_SUPPORTED );
mbedtls_ecp_keypair_init( &ecp );
ret = mbedtls_ecp_gen_key( grp_id, &ecp,
mbedtls_psa_get_random,
MBEDTLS_PSA_RANDOM_STATE );
if( ret != 0 )
{
mbedtls_ecp_keypair_free( &ecp );
return( mbedtls_to_psa_error( ret ) );
}
status = mbedtls_to_psa_error(
mbedtls_ecp_write_key( &ecp, key_buffer, key_buffer_size ) );
mbedtls_ecp_keypair_free( &ecp );
if( status == PSA_SUCCESS )
*key_buffer_length = key_buffer_size;
return( status );
}
#endif /* defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_ECC_KEY_PAIR) */
/****************************************************************/
/* ECDSA sign/verify */
/****************************************************************/
#if defined(MBEDTLS_PSA_BUILTIN_ALG_ECDSA) || \
defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA)
psa_status_t mbedtls_psa_ecdsa_sign_hash(
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer, size_t key_buffer_size,
psa_algorithm_t alg, const uint8_t *hash, size_t hash_length,
uint8_t *signature, size_t signature_size, size_t *signature_length )
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
mbedtls_ecp_keypair *ecp = NULL;
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
size_t curve_bytes;
mbedtls_mpi r, s;
status = mbedtls_psa_ecp_load_representation( attributes->core.type,
attributes->core.bits,
key_buffer,
key_buffer_size,
&ecp );
if( status != PSA_SUCCESS )
return( status );
curve_bytes = PSA_BITS_TO_BYTES( ecp->grp.pbits );
mbedtls_mpi_init( &r );
mbedtls_mpi_init( &s );
if( signature_size < 2 * curve_bytes )
{
ret = MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL;
goto cleanup;
}
if( PSA_ALG_ECDSA_IS_DETERMINISTIC( alg ) )
{
#if defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA)
psa_algorithm_t hash_alg = PSA_ALG_SIGN_GET_HASH( alg );
const mbedtls_md_info_t *md_info = mbedtls_md_info_from_psa( hash_alg );
mbedtls_md_type_t md_alg = mbedtls_md_get_type( md_info );
MBEDTLS_MPI_CHK( mbedtls_ecdsa_sign_det_ext(
&ecp->grp, &r, &s,
&ecp->d, hash,
hash_length, md_alg,
mbedtls_psa_get_random,
MBEDTLS_PSA_RANDOM_STATE ) );
#else
ret = MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE;
goto cleanup;
#endif /* defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA) */
}
else
{
(void) alg;
MBEDTLS_MPI_CHK( mbedtls_ecdsa_sign( &ecp->grp, &r, &s, &ecp->d,
hash, hash_length,
mbedtls_psa_get_random,
MBEDTLS_PSA_RANDOM_STATE ) );
}
MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( &r,
signature,
curve_bytes ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( &s,
signature + curve_bytes,
curve_bytes ) );
cleanup:
mbedtls_mpi_free( &r );
mbedtls_mpi_free( &s );
if( ret == 0 )
*signature_length = 2 * curve_bytes;
mbedtls_ecp_keypair_free( ecp );
mbedtls_free( ecp );
return( mbedtls_to_psa_error( ret ) );
}
psa_status_t mbedtls_psa_ecdsa_verify_hash(
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer, size_t key_buffer_size,
psa_algorithm_t alg, const uint8_t *hash, size_t hash_length,
const uint8_t *signature, size_t signature_length )
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
mbedtls_ecp_keypair *ecp = NULL;
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
size_t curve_bytes;
mbedtls_mpi r, s;
(void)alg;
status = mbedtls_psa_ecp_load_representation( attributes->core.type,
attributes->core.bits,
key_buffer,
key_buffer_size,
&ecp );
if( status != PSA_SUCCESS )
return( status );
curve_bytes = PSA_BITS_TO_BYTES( ecp->grp.pbits );
mbedtls_mpi_init( &r );
mbedtls_mpi_init( &s );
if( signature_length != 2 * curve_bytes )
{
ret = MBEDTLS_ERR_ECP_VERIFY_FAILED;
goto cleanup;
}
MBEDTLS_MPI_CHK( mbedtls_mpi_read_binary( &r,
signature,
curve_bytes ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_read_binary( &s,
signature + curve_bytes,
curve_bytes ) );
/* Check whether the public part is loaded. If not, load it. */
if( mbedtls_ecp_is_zero( &ecp->Q ) )
{
MBEDTLS_MPI_CHK(
mbedtls_ecp_mul( &ecp->grp, &ecp->Q, &ecp->d, &ecp->grp.G,
mbedtls_psa_get_random, MBEDTLS_PSA_RANDOM_STATE ) );
}
ret = mbedtls_ecdsa_verify( &ecp->grp, hash, hash_length,
&ecp->Q, &r, &s );
cleanup:
mbedtls_mpi_free( &r );
mbedtls_mpi_free( &s );
mbedtls_ecp_keypair_free( ecp );
mbedtls_free( ecp );
return( mbedtls_to_psa_error( ret ) );
}
#endif /* defined(MBEDTLS_PSA_BUILTIN_ALG_ECDSA) || \
* defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA) */
#endif /* MBEDTLS_PSA_CRYPTO_C */