Address review comments
* zero key buffer on failure
* readability improvements
* psa_finish_key_creation adjustment after removing import_key_into_slot
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
diff --git a/library/psa_crypto.c b/library/psa_crypto.c
index 74b9871..79ecf80 100644
--- a/library/psa_crypto.c
+++ b/library/psa_crypto.c
@@ -1039,6 +1039,8 @@
* psa_start_key_creation() wrote the size declared by the
* caller, which may be 0 (meaning unspecified) or wrong. */
slot->attr.bits = (psa_key_bits_t) bit_size;
+
+ return( PSA_SUCCESS );
}
else if( PSA_KEY_TYPE_IS_ASYMMETRIC( slot->attr.type ) )
{
@@ -1067,41 +1069,27 @@
/* Key format is not supported by any accelerator, try software fallback
* if present. */
+#if defined(MBEDTLS_ECP_C)
if( PSA_KEY_TYPE_IS_ECC( slot->attr.type ) )
{
-#if defined(MBEDTLS_ECP_C)
- status = psa_import_ecp_key( slot,
- data, data_length );
-#else
- /* No drivers have been implemented yet, so without mbed TLS backing
- * there's no way to do ECP with the current library. */
- status = PSA_ERROR_NOT_SUPPORTED;
+ return( psa_import_ecp_key( slot, data, data_length ) );
+ }
#endif /* defined(MBEDTLS_ECP_C) */
- }
- else if( PSA_KEY_TYPE_IS_RSA( slot->attr.type ) )
- {
#if defined(MBEDTLS_RSA_C)
- status = psa_import_rsa_key( slot,
- data, data_length );
-#else
- /* No drivers have been implemented yet, so without mbed TLS backing
- * there's no way to do RSA with the current library. */
- status = PSA_ERROR_NOT_SUPPORTED;
-#endif /* defined(MBEDTLS_RSA_C) */
- }
- else
+ if( PSA_KEY_TYPE_IS_RSA( slot->attr.type ) )
{
- /* Unsupported asymmetric key type */
- status = PSA_ERROR_NOT_SUPPORTED;
+ return( psa_import_rsa_key( slot, data, data_length ) );
}
+#endif /* defined(MBEDTLS_RSA_C) */
+
+ /* Fell through the fallback as well, so have nothing else to try. */
+ return( PSA_ERROR_NOT_SUPPORTED );
}
else
{
/* Unknown key type */
- status = PSA_ERROR_NOT_SUPPORTED;
+ return( PSA_ERROR_NOT_SUPPORTED );
}
-
- return( status );
}
/** Calculate the intersection of two algorithm usage policies.
@@ -1977,22 +1965,11 @@
else
#endif /* MBEDTLS_PSA_CRYPTO_SE_C */
{
- size_t buffer_size =
- PSA_KEY_EXPORT_MAX_SIZE( slot->attr.type,
- slot->attr.bits );
- uint8_t *buffer = mbedtls_calloc( 1, buffer_size );
- size_t length = 0;
- if( buffer == NULL )
- return( PSA_ERROR_INSUFFICIENT_MEMORY );
- status = psa_internal_export_key( slot,
- buffer, buffer_size, &length,
- 0 );
- if( status == PSA_SUCCESS )
- status = psa_save_persistent_key( &slot->attr,
- buffer, length );
-
- mbedtls_platform_zeroize( buffer, buffer_size );
- mbedtls_free( buffer );
+ /* Key material is saved in export representation in the slot, so
+ * just pass the slot buffer for storage. */
+ status = psa_save_persistent_key( &slot->attr,
+ slot->data.key.data,
+ slot->data.key.bytes );
}
}
#endif /* defined(MBEDTLS_PSA_CRYPTO_STORAGE_C) */