262 lines
8.2 KiB
C
262 lines
8.2 KiB
C
/*
|
|
* PSA FFDH 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_ffdh.h"
|
|
#include "psa_crypto_random_impl.h"
|
|
|
|
#if defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_DH_KEY_PAIR) || \
|
|
defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_DH_PUBLIC_KEY)
|
|
static psa_status_t mbedtls_psa_ffdh_set_prime_generator(size_t key_size,
|
|
mbedtls_mpi *P,
|
|
mbedtls_mpi *G)
|
|
{
|
|
const unsigned char *dhm_P = NULL;
|
|
const unsigned char *dhm_G = NULL;
|
|
size_t dhm_size_P = 0;
|
|
size_t dhm_size_G = 0;
|
|
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
|
|
|
|
if (P == NULL && G == NULL) {
|
|
return PSA_ERROR_INVALID_ARGUMENT;
|
|
}
|
|
|
|
static const unsigned char dhm_P_2048[] =
|
|
MBEDTLS_DHM_RFC7919_FFDHE2048_P_BIN;
|
|
static const unsigned char dhm_P_3072[] =
|
|
MBEDTLS_DHM_RFC7919_FFDHE3072_P_BIN;
|
|
static const unsigned char dhm_P_4096[] =
|
|
MBEDTLS_DHM_RFC7919_FFDHE4096_P_BIN;
|
|
static const unsigned char dhm_P_6144[] =
|
|
MBEDTLS_DHM_RFC7919_FFDHE6144_P_BIN;
|
|
static const unsigned char dhm_P_8192[] =
|
|
MBEDTLS_DHM_RFC7919_FFDHE8192_P_BIN;
|
|
static const unsigned char dhm_G_2048[] =
|
|
MBEDTLS_DHM_RFC7919_FFDHE2048_G_BIN;
|
|
static const unsigned char dhm_G_3072[] =
|
|
MBEDTLS_DHM_RFC7919_FFDHE3072_G_BIN;
|
|
static const unsigned char dhm_G_4096[] =
|
|
MBEDTLS_DHM_RFC7919_FFDHE4096_G_BIN;
|
|
static const unsigned char dhm_G_6144[] =
|
|
MBEDTLS_DHM_RFC7919_FFDHE6144_G_BIN;
|
|
static const unsigned char dhm_G_8192[] =
|
|
MBEDTLS_DHM_RFC7919_FFDHE8192_G_BIN;
|
|
|
|
switch (key_size) {
|
|
case sizeof(dhm_P_2048):
|
|
dhm_P = dhm_P_2048;
|
|
dhm_G = dhm_G_2048;
|
|
dhm_size_P = sizeof(dhm_P_2048);
|
|
dhm_size_G = sizeof(dhm_G_2048);
|
|
break;
|
|
case sizeof(dhm_P_3072):
|
|
dhm_P = dhm_P_3072;
|
|
dhm_G = dhm_G_3072;
|
|
dhm_size_P = sizeof(dhm_P_3072);
|
|
dhm_size_G = sizeof(dhm_G_3072);
|
|
break;
|
|
case sizeof(dhm_P_4096):
|
|
dhm_P = dhm_P_4096;
|
|
dhm_G = dhm_G_4096;
|
|
dhm_size_P = sizeof(dhm_P_4096);
|
|
dhm_size_G = sizeof(dhm_G_4096);
|
|
break;
|
|
case sizeof(dhm_P_6144):
|
|
dhm_P = dhm_P_6144;
|
|
dhm_G = dhm_G_6144;
|
|
dhm_size_P = sizeof(dhm_P_6144);
|
|
dhm_size_G = sizeof(dhm_G_6144);
|
|
break;
|
|
case sizeof(dhm_P_8192):
|
|
dhm_P = dhm_P_8192;
|
|
dhm_G = dhm_G_8192;
|
|
dhm_size_P = sizeof(dhm_P_8192);
|
|
dhm_size_G = sizeof(dhm_G_8192);
|
|
break;
|
|
default:
|
|
return PSA_ERROR_INVALID_ARGUMENT;
|
|
}
|
|
|
|
if (P != NULL) {
|
|
MBEDTLS_MPI_CHK(mbedtls_mpi_read_binary(P, dhm_P,
|
|
dhm_size_P));
|
|
}
|
|
if (G != NULL) {
|
|
MBEDTLS_MPI_CHK(mbedtls_mpi_read_binary(G, dhm_G,
|
|
dhm_size_G));
|
|
}
|
|
|
|
cleanup:
|
|
if (ret != 0) {
|
|
return mbedtls_to_psa_error(ret);
|
|
}
|
|
|
|
return PSA_SUCCESS;
|
|
}
|
|
|
|
#if defined(MBEDTLS_PSA_BUILTIN_ALG_FFDH)
|
|
psa_status_t mbedtls_psa_key_agreement_ffdh(
|
|
const psa_key_attributes_t *attributes,
|
|
const uint8_t *peer_key,
|
|
size_t peer_key_length,
|
|
const uint8_t *key_buffer,
|
|
size_t key_buffer_size,
|
|
uint8_t *shared_secret,
|
|
size_t shared_secret_size,
|
|
size_t *shared_secret_length)
|
|
{
|
|
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
|
|
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
|
|
mbedtls_mpi P, G, X, GY, K;
|
|
const size_t calculated_shared_secret_size = peer_key_length;
|
|
|
|
if (peer_key_length != key_buffer_size ||
|
|
calculated_shared_secret_size > shared_secret_size) {
|
|
return PSA_ERROR_INVALID_ARGUMENT;
|
|
}
|
|
|
|
if (!PSA_KEY_TYPE_IS_DH_KEY_PAIR(psa_get_key_type(attributes))) {
|
|
return PSA_ERROR_INVALID_ARGUMENT;
|
|
}
|
|
|
|
mbedtls_mpi_init(&P); mbedtls_mpi_init(&G);
|
|
mbedtls_mpi_init(&X); mbedtls_mpi_init(&GY);
|
|
mbedtls_mpi_init(&K);
|
|
|
|
status = mbedtls_psa_ffdh_set_prime_generator(
|
|
PSA_BITS_TO_BYTES(attributes->core.bits), &P, &G);
|
|
|
|
if (status != PSA_SUCCESS) {
|
|
goto cleanup;
|
|
}
|
|
|
|
MBEDTLS_MPI_CHK(mbedtls_mpi_read_binary(&X, key_buffer,
|
|
key_buffer_size));
|
|
|
|
MBEDTLS_MPI_CHK(mbedtls_mpi_read_binary(&GY, peer_key,
|
|
peer_key_length));
|
|
|
|
/* Calculate shared secret public key: K = G^(XY) mod P = GY^X mod P */
|
|
MBEDTLS_MPI_CHK(mbedtls_mpi_exp_mod(&K, &GY, &X, &P, NULL));
|
|
|
|
MBEDTLS_MPI_CHK(mbedtls_mpi_write_binary(&K, shared_secret,
|
|
calculated_shared_secret_size));
|
|
|
|
*shared_secret_length = calculated_shared_secret_size;
|
|
|
|
ret = 0;
|
|
|
|
cleanup:
|
|
mbedtls_mpi_free(&P); mbedtls_mpi_free(&G);
|
|
mbedtls_mpi_free(&X); mbedtls_mpi_free(&GY);
|
|
mbedtls_mpi_free(&K);
|
|
|
|
if (status == PSA_SUCCESS && ret != 0) {
|
|
status = mbedtls_to_psa_error(ret);
|
|
}
|
|
|
|
return status;
|
|
}
|
|
#endif /* MBEDTLS_PSA_BUILTIN_ALG_FFDH */
|
|
|
|
psa_status_t mbedtls_psa_export_ffdh_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)
|
|
{
|
|
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
|
|
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
|
|
mbedtls_mpi GX, G, X, P;
|
|
(void) attributes;
|
|
|
|
mbedtls_mpi_init(&GX); mbedtls_mpi_init(&G);
|
|
mbedtls_mpi_init(&X); mbedtls_mpi_init(&P);
|
|
|
|
status = mbedtls_psa_ffdh_set_prime_generator(data_size, &P, &G);
|
|
|
|
if (status != PSA_SUCCESS) {
|
|
goto cleanup;
|
|
}
|
|
|
|
MBEDTLS_MPI_CHK(mbedtls_mpi_read_binary(&X, key_buffer,
|
|
key_buffer_size));
|
|
|
|
MBEDTLS_MPI_CHK(mbedtls_mpi_exp_mod(&GX, &G, &X, &P, NULL));
|
|
MBEDTLS_MPI_CHK(mbedtls_mpi_write_binary(&GX, data, data_size));
|
|
|
|
*data_length = data_size;
|
|
|
|
ret = 0;
|
|
cleanup:
|
|
mbedtls_mpi_free(&P); mbedtls_mpi_free(&G);
|
|
mbedtls_mpi_free(&X); mbedtls_mpi_free(&GX);
|
|
|
|
if (status == PSA_SUCCESS && ret != 0) {
|
|
status = mbedtls_to_psa_error(ret);
|
|
}
|
|
|
|
return status;
|
|
}
|
|
|
|
psa_status_t mbedtls_psa_ffdh_generate_key(
|
|
const psa_key_attributes_t *attributes,
|
|
uint8_t *key_buffer, size_t key_buffer_size, size_t *key_buffer_length)
|
|
{
|
|
mbedtls_mpi X, P;
|
|
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
|
|
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
|
|
mbedtls_mpi_init(&P); mbedtls_mpi_init(&X);
|
|
(void) attributes;
|
|
|
|
status = mbedtls_psa_ffdh_set_prime_generator(key_buffer_size, &P, NULL);
|
|
|
|
if (status != PSA_SUCCESS) {
|
|
goto cleanup;
|
|
}
|
|
|
|
/* RFC7919: Traditional finite field Diffie-Hellman has each peer choose their
|
|
secret exponent from the range [2, P-2].
|
|
Select random value in range [3, P-1] and decrease it by 1. */
|
|
MBEDTLS_MPI_CHK(mbedtls_mpi_random(&X, 3, &P, mbedtls_psa_get_random,
|
|
MBEDTLS_PSA_RANDOM_STATE));
|
|
MBEDTLS_MPI_CHK(mbedtls_mpi_sub_int(&X, &X, 1));
|
|
MBEDTLS_MPI_CHK(mbedtls_mpi_write_binary(&X, key_buffer, key_buffer_size));
|
|
*key_buffer_length = key_buffer_size;
|
|
|
|
cleanup:
|
|
mbedtls_mpi_free(&P); mbedtls_mpi_free(&X);
|
|
if (status == PSA_SUCCESS && ret != 0) {
|
|
return mbedtls_to_psa_error(ret);
|
|
}
|
|
|
|
return status;
|
|
}
|
|
#endif /* MBEDTLS_PSA_BUILTIN_KEY_TYPE_DH_KEY_PAIR ||
|
|
MBEDTLS_PSA_BUILTIN_KEY_TYPE_DH_PUBLIC_KEY */
|
|
|
|
#endif /* MBEDTLS_PSA_CRYPTO_C */
|