Key derivation#

sl_se_ecjpake_role_t#

sl_se_ecjpake_role_t

Roles in the EC J-PAKE exchange.

sl_se_pbkdf2_prf_type_t#

typedef sl_se_hash_type_t sl_se_pbkdf2_prf_type_t

Typedef sl_se_pbkdf2_prf_type_t to sl_se_hash_type_t in order to maintain backward compatibility.

Defines for mapping the PRF identifiers to the underlying hash enum values exists in sl_se_manager_defines.h.

sl_se_ecdh_compute_shared_secret#

sl_status_t sl_se_ecdh_compute_shared_secret (sl_se_command_context_t * cmd_ctx, const sl_se_key_descriptor_t * key_in_priv, const sl_se_key_descriptor_t * key_in_pub, const sl_se_key_descriptor_t * key_out)

This function computes the shared secret with Elliptic Curve Diffie Hellman (ECDH) algorithm.

Performs Elliptic Curve Diffie Hellman shared secret computation.

Note

• P-521 Elliptic Curve based Elliptic Curve Diffie Hellman (ECDH) expects a 544 bits (68 bytes) buffer for storing private keys, and a 1088 bits (136 bytes) buffer for storing public keys and shared secret. The first 23 bits of d, Qx, Qy and shared secret are padding bits to comply word-aligned addressing. The padding bits are ignored in the computation.

This function does not implement the value-checking of the shared secret as described in RFC7748 when using Montgomery keys.

In case of using custom domain curves, key_in_priv defines the domain parameters. Moreover, key_in_pub should always contain a public key. If key_in_pub contains a private key, sl_se_export_public_key() can be used to export the public key.

Returns

• SL_STATUS_INVALID_KEY if key_in_pub does not contain a public key when using custom domain curves, otherwise an appropriate error code (sl_status.h).

sl_se_ecjpake_check#

sl_status_t sl_se_ecjpake_check (const sl_se_ecjpake_context_t * ctx)

Check if an EC J-PAKE context is ready for use.

Returns

• SL_STATUS_OK when the command was executed successfully, otherwise an appropriate error code (sl_status.h).

sl_se_ecjpake_derive_secret#

sl_status_t sl_se_ecjpake_derive_secret (sl_se_ecjpake_context_t * ctx, unsigned char * buf, size_t len, size_t * olen)

Derive the shared secret (TLS: Pre-Master Secret).

Returns

• SL_STATUS_OK when the command was executed successfully, otherwise an appropriate error code (sl_status.h).

sl_se_ecjpake_free#

sl_status_t sl_se_ecjpake_free (sl_se_ecjpake_context_t * ctx)

This clears an EC J-PAKE context and frees any embedded data structure.

Returns

• SL_STATUS_OK when the command was executed successfully, otherwise an appropriate error code (sl_status.h).

sl_se_ecjpake_init#

sl_status_t sl_se_ecjpake_init (sl_se_ecjpake_context_t * ctx, sl_se_command_context_t * cmd_ctx)

Initialize an EC J-PAKE context.

Returns

• SL_STATUS_OK when the command was executed successfully, otherwise an appropriate error code (sl_status.h).

sl_se_ecjpake_read_round_one#

sl_status_t sl_se_ecjpake_read_round_one (sl_se_ecjpake_context_t * ctx, const unsigned char * buf, size_t len)

Read and process the first round message (TLS: contents of the Client/ServerHello extension, excluding extension type and length bytes).

Returns

• SL_STATUS_OK when the command was executed successfully, otherwise an appropriate error code (sl_status.h).

sl_se_ecjpake_read_round_two#

sl_status_t sl_se_ecjpake_read_round_two (sl_se_ecjpake_context_t * ctx, const unsigned char * buf, size_t len)

Read and process the second round message (TLS: contents of the Client/ServerKeyExchange).

Returns

• SL_STATUS_OK when the command was executed successfully, otherwise an appropriate error code (sl_status.h).

sl_se_ecjpake_setup#

sl_status_t sl_se_ecjpake_setup (sl_se_ecjpake_context_t * ctx, sl_se_ecjpake_role_t role, sl_se_hash_type_t hash, uint32_t curve, const unsigned char * secret, size_t len)

Set up an EC J-PAKE context for use.

Note

• Currently the only values for hash/curve allowed by the standard are SL_SE_HASH_SHA256 / SL_SE_KEY_TYPE_ECC_P256.

Returns

• SL_STATUS_OK when the command was executed successfully, otherwise an appropriate error code (sl_status.h).

sl_se_ecjpake_write_round_one#

sl_status_t sl_se_ecjpake_write_round_one (sl_se_ecjpake_context_t * ctx, unsigned char * buf, size_t len, size_t * olen)

Generate and write the first round message (TLS: contents of the Client/ServerHello extension, excluding extension type and length bytes).

Returns

• SL_STATUS_OK when the command was executed successfully, otherwise an appropriate error code (sl_status.h).

sl_se_ecjpake_write_round_two#

sl_status_t sl_se_ecjpake_write_round_two (sl_se_ecjpake_context_t * ctx, unsigned char * buf, size_t len, size_t * olen)

Generate and write the second round message (TLS: contents of the Client/ServerKeyExchange).

Returns

• SL_STATUS_OK when the command was executed successfully, otherwise an appropriate error code (sl_status.h).

sl_se_derive_key_hkdf#

sl_status_t sl_se_derive_key_hkdf (sl_se_command_context_t * cmd_ctx, const sl_se_key_descriptor_t * in_key, sl_se_hash_type_t hash, const unsigned char * salt, size_t salt_len, const unsigned char * info, size_t info_len, sl_se_key_descriptor_t * out_key)

Derive a pseudorandom key from the input key material using HKDF.

Returns

• SL_STATUS_OK if the signature is successfully verified, otherwise an appropriate error code (sl_status.h).

sl_se_derive_key_pbkdf2#

sl_status_t sl_se_derive_key_pbkdf2 (sl_se_command_context_t * cmd_ctx, const sl_se_key_descriptor_t * in_key, sl_se_pbkdf2_prf_type_t prf, const unsigned char * salt, size_t salt_len, uint32_t iterations, sl_se_key_descriptor_t * out_key)

Derive a pseudorandom key from the input key material using PBKDF2.

Returns

• SL_STATUS_OK if the signature is successfully verified, otherwise an appropriate error code (sl_status.h).

SL_SE_PRF_AES_CMAC_128#

#define SL_SE_PRF_AES_CMAC_128

SL_SE_HASH_NONE

Defines mapping the PBKDF2 PRFs to corresponding sl_se_hash_type_t values.

CMAC-AES-128

SL_SE_PRF_HMAC_SHA1#

#define SL_SE_PRF_HMAC_SHA1

SL_SE_HASH_SHA1

HMAC-SHA-1.

SL_SE_PRF_HMAC_SHA224#

#define SL_SE_PRF_HMAC_SHA224

SL_SE_HASH_SHA224

HMAC-SHA-224.

SL_SE_PRF_HMAC_SHA256#

#define SL_SE_PRF_HMAC_SHA256

SL_SE_HASH_SHA256

HMAC-SHA-256.

SL_SE_PRF_HMAC_SHA384#

#define SL_SE_PRF_HMAC_SHA384

SL_SE_HASH_SHA384

HMAC-SHA-384.

SL_SE_PRF_HMAC_SHA512#

#define SL_SE_PRF_HMAC_SHA512

SL_SE_HASH_SHA512

HMAC-SHA-512.