Merge pull request #9236 from ronald-cron-arm/config-file-split
Configuration file split proposal
diff --git a/docs/proposed/Makefile b/docs/proposed/Makefile
index 1c31464..7f5254f 100644
--- a/docs/proposed/Makefile
+++ b/docs/proposed/Makefile
@@ -3,6 +3,7 @@
default: all
all_markdown = \
+ config-split.md \
psa-conditional-inclusion-c.md \
psa-driver-developer-guide.md \
psa-driver-integration-guide.md \
diff --git a/docs/proposed/config-split.md b/docs/proposed/config-split.md
new file mode 100644
index 0000000..fd8a8c7
--- /dev/null
+++ b/docs/proposed/config-split.md
@@ -0,0 +1,468 @@
+Configuration file split
+========================
+
+## Why split the configuration file?
+
+The objective of the repository split is to reach the point where in Mbed TLS
+all the cryptography code and its tests are located in a `tf-psa-crypto`
+directory that just contains the TF-PSA-Crypto repository as a submodule.
+The cryptography APIs exposed by Mbed TLS are just the TF-PSA-Crypto ones.
+Mbed TLS relies solely on the TF-PSA-Crypto build system to build its
+cryptography library and its tests.
+
+The TF-PSA-Crypto configuration file `tf_psa_crypto_config.h` configures
+entirely the cryptography interface exposed by Mbed TLS through TF-PSA-Crypto.
+Mbed TLS configuration is split in two files: `mbedtls_config.h` for TLS and
+x509, `tf_psa_crypto_config.h` for the cryptography.
+
+## How do we split the configuration file?
+
+We extend the so-called PSA cryptographic configuration scheme based on
+`mbedtls_config.h` and `crypto_config.h`. The configuration file `crypto_config.h`
+is extended to become the TF-PSA-Crypto configuration file, `mbedtls_config.h`
+becomes the configuration file for the TLS and x509 libraries. All the options
+to select the cryptographic mechanisms and to configure their implementation
+are moved from `mbedtls_config.h` to `(tf_psa_)crypto_config.h`.
+
+The configuration options that are relevant to both Mbed TLS and TF-PSA-Crypto
+like platform or system ones are moved to `(tf_psa_)crypto_config.h`. That way
+they are available in both repositories (as Mbed TLS includes
+`tf_psa_crypto_config.h`) without duplication. Later, we may duplicate or
+create aliases for some of them to align with the naming conventions of the
+repositories.
+
+The cryptographic configuration options in `tf_psa_crypto_config.h` are
+organized into sections that are different from the ones in the pre-split
+`mbedtls_config.h` (see below). This is first to take into account the
+specifics of TF-PSA-Crypto, for example a specific section for the
+configuration of builtin drivers. We also get rid of the grouping of non
+boolean options into a dedicated section: related boolean and non boolean
+configuration options are rather grouped together into the same section.
+
+Finally, for consistency, the sections in `mbedtls_config.h` are reorganized
+to be better aligned with the `tf_psa_crypto_config.h` ones.
+
+
+## Configuration files and `config.py`
+
+Each repository contains a `config.py` script to create and modify
+configurations.
+
+In Mbed TLS, `config.py` handles both `mbedtls_config.h` and
+`tf_psa_crypto_config.h`. It can set or unset TLS, x509 and cryptographic
+configuration options without having to specify the configuration file the
+options belong to. Commands like full and baremetal affect both configuration
+files.
+
+In TF-PSA-Crypto, `config.py` addresses only `tf_psa_crypto_config.h`.
+
+## Sections in `tf_psa_crypto_config.h`
+
+The `tf_psa_crypto_config.h` configuration file is organized into eight
+sections.
+
+The pre-split `mbedtls_config.h` configuration file contains configuration
+options that apply to the whole code base (TLS, x509, crypto and tests) mostly
+related to the platform abstraction layer and testing. In
+`tf_psa_crypto_config.h` these configurations options are organized into two
+sections, one for the platform abstraction layer options and one for the others,
+respectively named ["Platform abstraction layer"](#section-platform-abstraction-layer)
+and ["General and test configuration options"](#section-general-and-test-configuration-options).
+
+Then, the ["Cryptographic mechanism selection (PSA API)"](#section-cryptographic-mechanism-selection-PSA-API)
+section is the equivalent of the pre-split `crypto_config.h` configuration file
+containing the PSA_WANT_ prefixed macros.
+
+The following section named
+["Cryptographic mechanism selection (extended API)"](#section-cryptographic-mechanism-selection-extended-API)
+contains the configuration options for the cryptography mechanisms that are not
+yet part of the PSA cryptography API (like LMS or PK).
+
+It is followed by the ["Data format support"](#section-data-format-support)
+section that contains configuration options of utilities related to various data
+formats (like Base64 or ASN.1 APIs). These utilities aim to facilitate the
+usage of the PSA cryptography API in other cryptography projects.
+
+Compared to Mbed TLS, the cryptography code in TF-PSA-Crypto is not located
+in a single directory but split between the PSA core (core directory) and the
+PSA builtin drivers (drivers/builtin/src directory). This is reflected in
+`tf_psa_crypto_config.h` with two sections respectively named ["PSA core"](#section-psa-core)
+and ["Builtin drivers"](#section-builtin-drivers).
+
+Finally, the last section named ["Legacy cryptography"](#section-legacy-cryptography)
+contains the configuration options that will eventually be removed as duplicates
+of PSA_WANT_\* and MBEDTLS_PSA_ACCEL_\* configuration options.
+
+## Sections in `mbedtls_config.h`
+
+The sections in `mbedtls_config.h` are reorganized to be better aligned with
+the ones in `tf_psa_crypto_config.h`. The main change is the reorganization
+of the "Mbed TLS modules", "Mbed TLS feature support" and
+"Module configuration options" sections into the
+["TLS feature selection"](#section-tls-feature-selection) and
+["X.509 feature selection"](#section-x-509-feature-selection) sections. That
+way all TLS/x509 options are grouped into one section and there is no
+section dedicated to non boolean configuration options anymore.
+
+
+## Repartition of the configuration options
+
+### In `tf_psa_crypto_config.h`, we have:
+#### SECTION Platform abstraction layer
+```
+#define MBEDTLS_FS_IO
+#define MBEDTLS_HAVE_TIME
+#define MBEDTLS_HAVE_TIME_DATE
+//#define MBEDTLS_MEMORY_BACKTRACE
+//#define MBEDTLS_MEMORY_DEBUG
+#define MBEDTLS_PLATFORM_C
+//#define MBEDTLS_PLATFORM_EXIT_ALT
+//#define MBEDTLS_PLATFORM_FPRINTF_ALT
+//#define MBEDTLS_PLATFORM_GMTIME_R_ALT
+//#define MBEDTLS_PLATFORM_MEMORY
+//#define MBEDTLS_PLATFORM_MS_TIME_ALT
+//#define MBEDTLS_PLATFORM_NO_STD_FUNCTIONS
+//#define MBEDTLS_PLATFORM_NV_SEED_ALT
+//#define MBEDTLS_PLATFORM_PRINTF_ALT
+//#define MBEDTLS_PLATFORM_SETBUF_ALT
+//#define MBEDTLS_PLATFORM_SETUP_TEARDOWN_ALT
+//#define MBEDTLS_PLATFORM_SNPRINTF_ALT
+//#define MBEDTLS_PLATFORM_TIME_ALT
+//#define MBEDTLS_PLATFORM_VSNPRINTF_ALT
+//#define MBEDTLS_PLATFORM_ZEROIZE_ALT
+//#define MBEDTLS_THREADING_ALT
+//#define MBEDTLS_THREADING_C
+//#define MBEDTLS_THREADING_PTHREAD
+
+//#define MBEDTLS_MEMORY_ALIGN_MULTIPLE 4
+//#define MBEDTLS_PLATFORM_CALLOC_MACRO calloc
+//#define MBEDTLS_PLATFORM_EXIT_MACRO exit
+//#define MBEDTLS_PLATFORM_FREE_MACRO free
+//#define MBEDTLS_PLATFORM_FPRINTF_MACRO fprintf
+//#define MBEDTLS_PLATFORM_MS_TIME_TYPE_MACRO int64_t
+//#define MBEDTLS_PLATFORM_NV_SEED_READ_MACRO mbedtls_platform_std_nv_seed_read
+//#define MBEDTLS_PLATFORM_NV_SEED_WRITE_MACRO mbedtls_platform_std_nv_seed_write
+//#define MBEDTLS_PLATFORM_PRINTF_MACRO printf
+//#define MBEDTLS_PLATFORM_SETBUF_MACRO setbuf
+//#define MBEDTLS_PLATFORM_SNPRINTF_MACRO snprintf
+//#define MBEDTLS_PLATFORM_STD_CALLOC calloc
+//#define MBEDTLS_PLATFORM_STD_EXIT exit
+//#define MBEDTLS_PLATFORM_STD_EXIT_FAILURE 1
+//#define MBEDTLS_PLATFORM_STD_EXIT_SUCCESS 0
+//#define MBEDTLS_PLATFORM_STD_FPRINTF fprintf
+//#define MBEDTLS_PLATFORM_STD_FREE free
+//#define MBEDTLS_PLATFORM_STD_MEM_HDR <stdlib.h>
+//#define MBEDTLS_PLATFORM_STD_NV_SEED_FILE "seedfile"
+//#define MBEDTLS_PLATFORM_STD_NV_SEED_READ mbedtls_platform_std_nv_seed_read
+//#define MBEDTLS_PLATFORM_STD_NV_SEED_WRITE mbedtls_platform_std_nv_seed_write
+//#define MBEDTLS_PLATFORM_STD_PRINTF printf
+//#define MBEDTLS_PLATFORM_STD_SETBUF setbuf
+//#define MBEDTLS_PLATFORM_STD_SNPRINTF snprintf
+//#define MBEDTLS_PLATFORM_STD_TIME time
+//#define MBEDTLS_PLATFORM_TIME_MACRO time
+//#define MBEDTLS_PLATFORM_TIME_TYPE_MACRO time_t
+//#define MBEDTLS_PLATFORM_VSNPRINTF_MACRO vsnprintf
+//#define MBEDTLS_PRINTF_MS_TIME PRId64
+```
+
+#### SECTION General and test configuration options
+Note: for consistency with the configuration file name change from
+`crypto_config.h` to `tf_psa_crypto_config.h`, the configuration options
+`MBEDTLS_PSA_CRYPTO_CONFIG_FILE` and `MBEDTLS_PSA_CRYPTO_USER_CONFIG_FILE` are
+respectively renamed `TF_PSA_CRYPTO_CONFIG_FILE` and
+`TF_PSA_CRYPTO_USER_CONFIG_FILE`. These are the only configuration options
+renamed by this document.
+```
+//#define MBEDTLS_CHECK_RETURN_WARNING
+//#define MBEDTLS_DEPRECATED_REMOVED
+//#define MBEDTLS_DEPRECATED_WARNING
+#define MBEDTLS_SELF_TEST
+//#define MBEDTLS_TEST_CONSTANT_FLOW_MEMSAN
+//#define MBEDTLS_TEST_CONSTANT_FLOW_VALGRIND
+//#define MBEDTLS_TEST_HOOKS
+
+//#define MBEDTLS_CHECK_RETURN __attribute__((__warn_unused_result__))
+//#define MBEDTLS_IGNORE_RETURN( result ) ((void) !(result))
+//#define TF_PSA_CRYPTO_CONFIG_FILE "psa/tf_psa_crypto_config.h"
+//#define TF_PSA_CRYPTO_USER_CONFIG_FILE "/dev/null"
+```
+
+#### SECTION Cryptographic mechanism selection (PSA API)
+PSA_WANT_\* macros as in current `crypto_config.h`.
+
+
+#### SECTION Cryptographic mechanism selection (extended API)
+```
+#define MBEDTLS_LMS_C
+//#define MBEDTLS_LMS_PRIVATE
+#define MBEDTLS_MD_C
+#define MBEDTLS_NIST_KW_C
+#define MBEDTLS_PKCS5_C
+#define MBEDTLS_PKCS12_C
+#define MBEDTLS_PK_C
+#define MBEDTLS_PK_PARSE_C
+#define MBEDTLS_PK_PARSE_EC_COMPRESSED
+#define MBEDTLS_PK_PARSE_EC_EXTENDED
+#define MBEDTLS_PK_RSA_ALT_SUPPORT
+#define MBEDTLS_PK_WRITE_C
+
+//#define MBEDTLS_CTR_DRBG_ENTROPY_LEN 48
+//#define MBEDTLS_CTR_DRBG_MAX_INPUT 256
+//#define MBEDTLS_CTR_DRBG_MAX_REQUEST 1024
+//#define MBEDTLS_CTR_DRBG_MAX_SEED_INPUT 384
+//#define MBEDTLS_CTR_DRBG_RESEED_INTERVAL 10000
+//#define MBEDTLS_HMAC_DRBG_MAX_INPUT 256
+//#define MBEDTLS_HMAC_DRBG_MAX_REQUEST 1024
+//#define MBEDTLS_HMAC_DRBG_MAX_SEED_INPUT 384
+//#define MBEDTLS_HMAC_DRBG_RESEED_INTERVAL 10000
+//#define MBEDTLS_PSA_HMAC_DRBG_MD_TYPE MBEDTLS_MD_SHA256
+```
+
+
+#### SECTION Data format support
+```
+#define MBEDTLS_ASN1_PARSE_C
+#define MBEDTLS_ASN1_WRITE_C
+#define MBEDTLS_BASE64_C
+#define MBEDTLS_OID_C
+#define MBEDTLS_PEM_PARSE_C
+#define MBEDTLS_PEM_WRITE_C
+```
+
+
+#### SECTION PSA core
+```
+#define MBEDTLS_ENTROPY_C
+//#define MBEDTLS_ENTROPY_FORCE_SHA256
+//#define MBEDTLS_ENTROPY_HARDWARE_ALT
+//#define MBEDTLS_ENTROPY_NV_SEED
+//#define MBEDTLS_NO_DEFAULT_ENTROPY_SOURCES
+//#define MBEDTLS_NO_PLATFORM_ENTROPY
+//#define MBEDTLS_PSA_ASSUME_EXCLUSIVE_BUFFERS
+//#define MBEDTLS_PSA_CRYPTO_BUILTIN_KEYS
+#define MBEDTLS_PSA_CRYPTO_C
+//#define MBEDTLS_PSA_CRYPTO_CLIENT
+//#define MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG
+//#define MBEDTLS_PSA_CRYPTO_KEY_ID_ENCODES_OWNER
+//#define MBEDTLS_PSA_CRYPTO_SPM
+#define MBEDTLS_PSA_CRYPTO_STORAGE_C
+//#define MBEDTLS_PSA_INJECT_ENTROPY
+#define MBEDTLS_PSA_ITS_FILE_C
+
+//#define MBEDTLS_ENTROPY_MAX_GATHER 128
+//#define MBEDTLS_ENTROPY_MAX_SOURCES 20
+//#define MBEDTLS_ENTROPY_MIN_HARDWARE 32
+//#define MBEDTLS_PSA_CRYPTO_PLATFORM_FILE "psa/crypto_platform_alt.h"
+//#define MBEDTLS_PSA_CRYPTO_STRUCT_FILE "psa/crypto_struct_alt.h"
+//#define MBEDTLS_PSA_KEY_SLOT_COUNT 32
+```
+
+#### SECTION Builtin drivers
+```
+#define MBEDTLS_AESCE_C
+#define MBEDTLS_AESNI_C
+//#define MBEDTLS_AES_FEWER_TABLES
+//#define MBEDTLS_AES_ONLY_128_BIT_KEY_LENGTH
+//#define MBEDTLS_AES_ROM_TABLES
+//#define MBEDTLS_AES_USE_HARDWARE_ONLY
+//#define MBEDTLS_BLOCK_CIPHER_NO_DECRYPT
+//#define MBEDTLS_CAMELLIA_SMALL_MEMORY
+//#define MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED
+#define MBEDTLS_ECP_NIST_OPTIM
+//#define MBEDTLS_ECP_RESTARTABLE
+//#define MBEDTLS_ECP_WITH_MPI_UINT
+//#define MBEDTLS_GCM_LARGE_TABLE
+#define MBEDTLS_HAVE_ASM
+//#define MBEDTLS_HAVE_SSE2
+//#define MBEDTLS_NO_UDBL_DIVISION
+//#define MBEDTLS_NO_64BIT_MULTIPLICATION
+//#define MBEDTLS_PSA_P256M_DRIVER_ENABLED
+//#define MBEDTLS_RSA_NO_CRT
+//#define MBEDTLS_SHA256_SMALLER
+//#define MBEDTLS_SHA256_USE_A64_CRYPTO_IF_PRESENT
+//#define MBEDTLS_SHA256_USE_A64_CRYPTO_ONLY
+//#define MBEDTLS_SHA256_USE_ARMV8_A_CRYPTO_IF_PRESENT
+//#define MBEDTLS_SHA256_USE_ARMV8_A_CRYPTO_ONLY
+//#define MBEDTLS_SHA512_SMALLER
+//#define MBEDTLS_SHA512_USE_A64_CRYPTO_IF_PRESENT
+//#define MBEDTLS_SHA512_USE_A64_CRYPTO_ONLY
+//#define MBEDTLS_USE_PSA_CRYPTO
+
+//#define MBEDTLS_ECP_FIXED_POINT_OPTIM 1
+//#define MBEDTLS_ECP_WINDOW_SIZE 4
+//#define MBEDTLS_MPI_MAX_SIZE 1024
+//#define MBEDTLS_MPI_WINDOW_SIZE 2
+//#define MBEDTLS_RSA_GEN_KEY_MIN_BITS 1024
+```
+
+
+#### SECTION Legacy cryptography
+```
+#define MBEDTLS_AES_C
+#define MBEDTLS_ARIA_C
+#define MBEDTLS_BIGNUM_C
+#define MBEDTLS_CAMELLIA_C
+#define MBEDTLS_CCM_C
+#define MBEDTLS_CHACHA20_C
+#define MBEDTLS_CHACHAPOLY_C
+#define MBEDTLS_CIPHER_C
+#define MBEDTLS_CIPHER_MODE_CBC
+#define MBEDTLS_CIPHER_MODE_CFB
+#define MBEDTLS_CIPHER_MODE_CTR
+#define MBEDTLS_CIPHER_MODE_OFB
+#define MBEDTLS_CIPHER_MODE_XTS
+#define MBEDTLS_CIPHER_PADDING_ONE_AND_ZEROS
+#define MBEDTLS_CIPHER_PADDING_PKCS7
+#define MBEDTLS_CIPHER_PADDING_ZEROS
+#define MBEDTLS_CIPHER_PADDING_ZEROS_AND_LEN
+#define MBEDTLS_CMAC_C
+#define MBEDTLS_CTR_DRBG_C
+//#define MBEDTLS_CTR_DRBG_USE_128_BIT_KEY
+#define MBEDTLS_DES_C
+#define MBEDTLS_DHM_C
+#define MBEDTLS_ECDH_C
+#define MBEDTLS_ECP_C
+#define MBEDTLS_ECP_DP_BP256R1_ENABLED
+#define MBEDTLS_ECP_DP_BP384R1_ENABLED
+#define MBEDTLS_ECP_DP_BP512R1_ENABLED
+#define MBEDTLS_ECP_DP_CURVE25519_ENABLED
+#define MBEDTLS_ECP_DP_CURVE448_ENABLED
+#define MBEDTLS_ECP_DP_SECP192K1_ENABLED
+#define MBEDTLS_ECP_DP_SECP192R1_ENABLED
+#define MBEDTLS_ECP_DP_SECP224K1_ENABLED
+#define MBEDTLS_ECP_DP_SECP224R1_ENABLED
+#define MBEDTLS_ECP_DP_SECP256K1_ENABLED
+#define MBEDTLS_ECP_DP_SECP256R1_ENABLED
+#define MBEDTLS_ECP_DP_SECP384R1_ENABLED
+#define MBEDTLS_ECP_DP_SECP521R1_ENABLED
+#define MBEDTLS_ECDSA_C
+#define MBEDTLS_ECDSA_DETERMINISTIC
+#define MBEDTLS_ECJPAKE_C
+#define MBEDTLS_GCM_C
+#define MBEDTLS_GENPRIME
+#define MBEDTLS_HKDF_C
+#define MBEDTLS_HMAC_DRBG_C
+#define MBEDTLS_MD5_C
+#define MBEDTLS_PADLOCK_C
+#define MBEDTLS_PKCS1_V15
+#define MBEDTLS_PKCS1_V21
+#define MBEDTLS_POLY1305_C
+//#define MBEDTLS_PSA_CRYPTO_CONFIG
+//#define MBEDTLS_PSA_CRYPTO_SE_C
+#define MBEDTLS_RIPEMD160_C
+#define MBEDTLS_RSA_C
+#define MBEDTLS_SHA1_C
+#define MBEDTLS_SHA224_C
+#define MBEDTLS_SHA256_C
+#define MBEDTLS_SHA384_C
+#define MBEDTLS_SHA3_C
+#define MBEDTLS_SHA512_C
+```
+
+
+### In `mbedtls_config.h`, we have:
+#### SECTION Platform abstraction layer
+```
+#define MBEDTLS_NET_C
+//#define MBEDTLS_TIMING_ALT
+#define MBEDTLS_TIMING_C
+```
+
+
+#### SECTION General configuration options
+```
+#define MBEDTLS_ERROR_C
+#define MBEDTLS_ERROR_STRERROR_DUMMY
+#define MBEDTLS_VERSION_C
+#define MBEDTLS_VERSION_FEATURES
+
+//#define MBEDTLS_CONFIG_FILE "mbedtls/mbedtls_config.h"
+//#define MBEDTLS_USER_CONFIG_FILE "/dev/null"
+```
+
+
+#### SECTION TLS feature selection
+```
+//#define MBEDTLS_CIPHER_NULL_CIPHER
+#define MBEDTLS_DEBUG_C
+#define MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED
+#define MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED
+#define MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED
+#define MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED
+#define MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED
+#define MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED
+#define MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED
+//#define MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED
+#define MBEDTLS_KEY_EXCHANGE_PSK_ENABLED
+#define MBEDTLS_KEY_EXCHANGE_RSA_ENABLED
+#define MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED
+#define MBEDTLS_SSL_ALL_ALERT_MESSAGES
+#define MBEDTLS_SSL_ALPN
+//#define MBEDTLS_SSL_ASYNC_PRIVATE
+#define MBEDTLS_SSL_CACHE_C
+#define MBEDTLS_SSL_CLI_C
+#define MBEDTLS_SSL_CONTEXT_SERIALIZATION
+#define MBEDTLS_SSL_COOKIE_C
+//#define MBEDTLS_SSL_DEBUG_ALL
+#define MBEDTLS_SSL_DTLS_ANTI_REPLAY
+#define MBEDTLS_SSL_DTLS_CLIENT_PORT_REUSE
+#define MBEDTLS_SSL_DTLS_CONNECTION_ID
+#define MBEDTLS_SSL_DTLS_CONNECTION_ID_COMPAT 0
+#define MBEDTLS_SSL_DTLS_HELLO_VERIFY
+//#define MBEDTLS_SSL_DTLS_SRTP
+//#define MBEDTLS_SSL_EARLY_DATA
+#define MBEDTLS_SSL_ENCRYPT_THEN_MAC
+#define MBEDTLS_SSL_EXTENDED_MASTER_SECRET
+#define MBEDTLS_SSL_KEEP_PEER_CERTIFICATE
+#define MBEDTLS_SSL_MAX_FRAGMENT_LENGTH
+#define MBEDTLS_SSL_PROTO_DTLS
+#define MBEDTLS_SSL_PROTO_TLS1_2
+#define MBEDTLS_SSL_PROTO_TLS1_3
+//#define MBEDTLS_SSL_RECORD_SIZE_LIMIT
+#define MBEDTLS_SSL_RENEGOTIATION
+#define MBEDTLS_SSL_SERVER_NAME_INDICATION
+#define MBEDTLS_SSL_SESSION_TICKETS
+#define MBEDTLS_SSL_SRV_C
+#define MBEDTLS_SSL_TICKET_C
+#define MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
+#define MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL_ENABLED
+#define MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_ENABLED
+#define MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL_ENABLED
+#define MBEDTLS_SSL_TLS_C
+//#define MBEDTLS_SSL_VARIABLE_BUFFER_LENGTH
+
+//#define MBEDTLS_PSK_MAX_LEN 32
+//#define MBEDTLS_SSL_CACHE_DEFAULT_MAX_ENTRIES 50
+//#define MBEDTLS_SSL_CACHE_DEFAULT_TIMEOUT 86400
+//#define MBEDTLS_SSL_CID_IN_LEN_MAX 32
+//#define MBEDTLS_SSL_CID_OUT_LEN_MAX 32
+//#define MBEDTLS_SSL_CID_TLS1_3_PADDING_GRANULARITY 16
+//#define MBEDTLS_SSL_CIPHERSUITES MBEDTLS_TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,MBEDTLS_TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256
+//#define MBEDTLS_SSL_COOKIE_TIMEOUT 60
+//#define MBEDTLS_SSL_DTLS_MAX_BUFFERING 32768
+//#define MBEDTLS_SSL_IN_CONTENT_LEN 16384
+//#define MBEDTLS_SSL_MAX_EARLY_DATA_SIZE 1024
+//#define MBEDTLS_SSL_OUT_CONTENT_LEN 16384
+//#define MBEDTLS_SSL_TLS1_3_DEFAULT_NEW_SESSION_TICKETS 1
+//#define MBEDTLS_SSL_TLS1_3_TICKET_AGE_TOLERANCE 6000
+//#define MBEDTLS_SSL_TLS1_3_TICKET_NONCE_LENGTH 32
+```
+
+
+#### SECTION X.509 feature selection
+```
+#define MBEDTLS_PKCS7_C
+#define MBEDTLS_X509_CREATE_C
+#define MBEDTLS_X509_CRL_PARSE_C
+#define MBEDTLS_X509_CRT_PARSE_C
+#define MBEDTLS_X509_CRT_WRITE_C
+#define MBEDTLS_X509_CSR_PARSE_C
+#define MBEDTLS_X509_CSR_WRITE_C
+//#define MBEDTLS_X509_REMOVE_INFO
+#define MBEDTLS_X509_RSASSA_PSS_SUPPORT
+//#define MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK
+#define MBEDTLS_X509_USE_C
+
+//#define MBEDTLS_X509_MAX_FILE_PATH_LEN 512
+//#define MBEDTLS_X509_MAX_INTERMEDIATE_CA 8
+```