configs/config-suite-b.h

/**
 * \file config-suite-b.h
 *
 * \brief Minimal configuration for TLS NSA Suite B Profile (RFC 6460)
 */
/*
 *  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.
 */
/*
 * Minimal configuration for TLS NSA Suite B Profile (RFC 6460)
 *
 * Distinguishing features:
 * - no RSA or classic DH, fully based on ECC
 * - optimized for low RAM usage
 *
 * Possible improvements:
 * - if 128-bit security is enough, disable secp384r1 and SHA-512
 * - use embedded certs in DER format and disable PEM_PARSE_C and BASE64_C
 *
 * See README.txt for usage instructions.
 */

/* System support */
#define MBEDTLS_HAVE_ASM
#define MBEDTLS_HAVE_TIME

/* mbed TLS feature support */
#define MBEDTLS_ECP_DP_SECP256R1_ENABLED
#define MBEDTLS_ECP_DP_SECP384R1_ENABLED
#define MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED
#define MBEDTLS_SSL_PROTO_TLS1_2

/* mbed TLS modules */
#define MBEDTLS_AES_C
#define MBEDTLS_ASN1_PARSE_C
#define MBEDTLS_ASN1_WRITE_C
#define MBEDTLS_BIGNUM_C
#define MBEDTLS_CIPHER_C
#define MBEDTLS_CTR_DRBG_C
#define MBEDTLS_ECDH_C
#define MBEDTLS_ECDSA_C
#define MBEDTLS_ECP_C
#define MBEDTLS_ENTROPY_C
#define MBEDTLS_GCM_C
#define MBEDTLS_MD_C
#define MBEDTLS_NET_C
#define MBEDTLS_OID_C
#define MBEDTLS_PK_C
#define MBEDTLS_PK_PARSE_C
/* The library does not currently support enabling SHA-224 without SHA-256.
 * A future version of the library will have this option disabled
 * by default. */
#define MBEDTLS_SHA224_C
#define MBEDTLS_SHA256_C
#define MBEDTLS_SHA384_C
#define MBEDTLS_SHA512_C
#define MBEDTLS_SSL_CLI_C
#define MBEDTLS_SSL_SRV_C
#define MBEDTLS_SSL_TLS_C
#define MBEDTLS_X509_CRT_PARSE_C
#define MBEDTLS_X509_USE_C

/* For test certificates */
#define MBEDTLS_BASE64_C
#define MBEDTLS_PEM_PARSE_C

/* Save RAM at the expense of ROM */
#define MBEDTLS_AES_ROM_TABLES

/* Save RAM by adjusting to our exact needs */
#define MBEDTLS_MPI_MAX_SIZE    48 // 384-bit EC curve = 48 bytes

/* Save RAM at the expense of speed, see ecp.h */
#define MBEDTLS_ECP_WINDOW_SIZE        2
#define MBEDTLS_ECP_FIXED_POINT_OPTIM  0

/* Significant speed benefit at the expense of some ROM */
#define MBEDTLS_ECP_NIST_OPTIM

/*
 * You should adjust this to the exact number of sources you're using: default
 * is the "mbedtls_platform_entropy_poll" source, but you may want to add other ones.
 * Minimum is 2 for the entropy test suite.
 */
#define MBEDTLS_ENTROPY_MAX_SOURCES 2

/* Save ROM and a few bytes of RAM by specifying our own ciphersuite list */
#define MBEDTLS_SSL_CIPHERSUITES                        \
    MBEDTLS_TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,    \
    MBEDTLS_TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256

/*
 * Save RAM at the expense of interoperability: do this only if you control
 * both ends of the connection!  (See coments in "mbedtls/ssl.h".)
 * The minimum size here depends on the certificate chain used as well as the
 * typical size of records.
 */
#define MBEDTLS_SSL_IN_CONTENT_LEN             1024
#define MBEDTLS_SSL_OUT_CONTENT_LEN             1024