psa: Move xxx_load_representation functions to RSA/ECP specific modules
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
diff --git a/library/psa_crypto_ecp.c b/library/psa_crypto_ecp.c
new file mode 100644
index 0000000..a4c6e14
--- /dev/null
+++ b/library/psa_crypto_ecp.c
@@ -0,0 +1,139 @@
+/*
+ * 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 <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/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_ECDH) || \
+ defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA)
+psa_status_t mbedtls_psa_ecp_load_representation(
+ psa_key_type_t type, 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_size = data_length;
+
+ 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_size = data_length / 2;
+
+ /* Montgomery public keys are represented in compressed format, meaning
+ * their curve_size is equal to the amount of input. */
+
+ /* Private keys are represented in uncompressed private random integer
+ * format, meaning their curve_size is equal to the amount of input. */
+ }
+
+ /* 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_size );
+ if( grp_id == MBEDTLS_ECP_DP_NONE )
+ {
+ status = PSA_ERROR_INVALID_ARGUMENT;
+ 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_ECDH) ||
+ * defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA) */
+
+#endif /* MBEDTLS_PSA_CRYPTO_C */