Add internal header for PSA utility functions
This commit adds the header file mbedtls/psa_util.h which contains
static utility functions `mbedtls_psa_xxx()` used in the integration
of PSA Crypto into Mbed TLS.
Warning: These functions are internal only and may change at any time.
diff --git a/include/mbedtls/psa_util.h b/include/mbedtls/psa_util.h
new file mode 100644
index 0000000..03c55e1
--- /dev/null
+++ b/include/mbedtls/psa_util.h
@@ -0,0 +1,162 @@
+/**
+ * \file psa_compat.h
+ *
+ * \brief Utility functions for the use of the PSA Crypto library.
+ *
+ * \warning This function is not part of the public API and may
+ * change at any time.
+ */
+/*
+ * Copyright (C) 2006-2018, ARM Limited, All Rights Reserved
+ * 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.
+ *
+ * This file is part of mbed TLS (https://tls.mbed.org)
+ */
+
+#if !defined(MBEDTLS_PSA_COMPAT_H)
+#define MBEDTLS_PSA_COMPAT_H
+
+#if !defined(MBEDTLS_CONFIG_FILE)
+#include "config.h"
+#else
+#include MBEDTLS_CONFIG_FILE
+#endif
+
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+
+#include "psa/crypto.h"
+
+#include "ecp.h"
+#include "md.h"
+
+static psa_status_t mbedtls_psa_get_free_key_slot( psa_key_slot_t *key )
+{
+ for( psa_key_slot_t slot = 1; slot <= 32; slot++ )
+ {
+ if( psa_get_key_information( slot, NULL, NULL ) == PSA_ERROR_EMPTY_SLOT )
+ {
+ *key = slot;
+ return( PSA_SUCCESS );
+ }
+ }
+ return( PSA_ERROR_INSUFFICIENT_MEMORY );
+}
+
+static psa_algorithm_t mbedtls_psa_translate_md( mbedtls_md_type_t md_alg )
+{
+ switch( md_alg )
+ {
+#if defined(MBEDTLS_MD2_C)
+ case MBEDTLS_MD_MD2:
+ return( PSA_ALG_MD2 );
+#endif
+#if defined(MBEDTLS_MD4_C)
+ case MBEDTLS_MD_MD4:
+ return( PSA_ALG_MD4 );
+#endif
+#if defined(MBEDTLS_MD5_C)
+ case MBEDTLS_MD_MD5:
+ return( PSA_ALG_MD5 );
+#endif
+#if defined(MBEDTLS_SHA1_C)
+ case MBEDTLS_MD_SHA1:
+ return( PSA_ALG_SHA_1 );
+#endif
+#if defined(MBEDTLS_SHA256_C)
+ case MBEDTLS_MD_SHA224:
+ return( PSA_ALG_SHA_224 );
+ case MBEDTLS_MD_SHA256:
+ return( PSA_ALG_SHA_256 );
+#endif
+#if defined(MBEDTLS_SHA512_C)
+ case MBEDTLS_MD_SHA384:
+ return( PSA_ALG_SHA_384 );
+ case MBEDTLS_MD_SHA512:
+ return( PSA_ALG_SHA_512 );
+#endif
+#if defined(MBEDTLS_RIPEMD160_C)
+ case MBEDTLS_MD_RIPEMD160:
+ return( PSA_ALG_RIPEMD160 );
+#endif
+ case MBEDTLS_MD_NONE: /* Intentional fallthrough */
+ default:
+ return( 0 );
+ }
+}
+
+static psa_ecc_curve_t mbedtls_psa_translate_ecc_group( mbedtls_ecp_group_id grpid )
+{
+ switch( grpid )
+ {
+#if defined(MBEDTLS_ECP_DP_SECP192R1_ENABLED)
+ case MBEDTLS_ECP_DP_SECP192R1:
+ return( PSA_ECC_CURVE_SECP192R1 );
+#endif
+#if defined(MBEDTLS_ECP_DP_SECP224R1_ENABLED)
+ case MBEDTLS_ECP_DP_SECP224R1:
+ return( PSA_ECC_CURVE_SECP224R1 );
+#endif
+#if defined(MBEDTLS_ECP_DP_SECP256R1_ENABLED)
+ case MBEDTLS_ECP_DP_SECP256R1:
+ return( PSA_ECC_CURVE_SECP256R1 );
+#endif
+#if defined(MBEDTLS_ECP_DP_SECP384R1_ENABLED)
+ case MBEDTLS_ECP_DP_SECP384R1:
+ return( PSA_ECC_CURVE_SECP384R1 );
+#endif
+#if defined(MBEDTLS_ECP_DP_SECP521R1_ENABLED)
+ case MBEDTLS_ECP_DP_SECP521R1:
+ return( PSA_ECC_CURVE_SECP521R1 );
+#endif
+#if defined(MBEDTLS_ECP_DP_BP256R1_ENABLED)
+ case MBEDTLS_ECP_DP_BP256R1:
+ return( PSA_ECC_CURVE_BRAINPOOL_P256R1 );
+#endif
+#if defined(MBEDTLS_ECP_DP_BP384R1_ENABLED)
+ case MBEDTLS_ECP_DP_BP384R1:
+ return( PSA_ECC_CURVE_BRAINPOOL_P384R1 );
+#endif
+#if defined(MBEDTLS_ECP_DP_BP512R1_ENABLED)
+ case MBEDTLS_ECP_DP_BP512R1:
+ return( PSA_ECC_CURVE_BRAINPOOL_P512R1 );
+#endif
+#if defined(MBEDTLS_ECP_DP_CURVE25519_ENABLED)
+ case MBEDTLS_ECP_DP_CURVE25519:
+ return( PSA_ECC_CURVE_CURVE25519 );
+#endif
+#if defined(MBEDTLS_ECP_DP_SECP192K1_ENABLED)
+ case MBEDTLS_ECP_DP_SECP192K1:
+ return( PSA_ECC_CURVE_SECP192K1 );
+#endif
+#if defined(MBEDTLS_ECP_DP_SECP224K1_ENABLED)
+ case MBEDTLS_ECP_DP_SECP224K1:
+ return( PSA_ECC_CURVE_SECP224K1 );
+#endif
+#if defined(MBEDTLS_ECP_DP_SECP256K1_ENABLED)
+ case MBEDTLS_ECP_DP_SECP256K1:
+ return( PSA_ECC_CURVE_SECP256K1 );
+#endif
+#if defined(MBEDTLS_ECP_DP_CURVE448_ENABLED)
+ case MBEDTLS_ECP_DP_CURVE448:
+ return( PSA_ECC_CURVE_CURVE448 );
+#endif
+ default:
+ return( 0 );
+ }
+}
+
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
+
+#endif /* MBEDTLS_PSA_COMPAT_H */
