ECDH P-256

Elliptic curve Diffie-Hellman algorithm based on the NIST P-256 curve (aka secp256r1). More...

Files
file	ocrypto_ecdh_p256.h
	Elliptic curve Diffie-Hellman algorithm based on the NIST P-256 curve (aka secp256r1).

Functions
int	ocrypto_ecdh_p256_secret_key_check (const uint8_t sk[32])
int	ocrypto_ecdh_p256_public_key_check (const uint8_t pk[64])
int	ocrypto_ecdh_p256_public_key (uint8_t pk[64], const uint8_t sk[32])
int	ocrypto_ecdh_p256_common_secret (uint8_t r[32], const uint8_t sk[32], const uint8_t pk[64])

Incremental ECDH P-256 calculation
This group of functions can be used to incrementally calculate the ECDH P-256 public key and common secret. Each call completes in less than 25ms on a 16MHz Cortex-M0. Use pattern: Public Key: ocrypto_ecdh_p256_public_key_init(ctx, sKey); while (ocrypto_ecdh_p256_public_key_iterate(ctx)); res = ocrypto_ecdh_p256_public_key_final(ctx, pKey); Common Secret: ocrypto_ecdh_p256_common_secret_init(ctx, sKey, pKey); while (ocrypto_ecdh_p256_common_secret_iterate(ctx)); res = ocrypto_ecdh_p256_common_secret_final(ctx, secet);
void	ocrypto_ecdh_p256_public_key_init (ocrypto_ecdh_p256_ctx *ctx, const uint8_t sk[32])
int	ocrypto_ecdh_p256_public_key_iterate (ocrypto_ecdh_p256_ctx *ctx)
int	ocrypto_ecdh_p256_public_key_final (ocrypto_ecdh_p256_ctx *ctx, uint8_t pk[64])
void	ocrypto_ecdh_p256_common_secret_init (ocrypto_ecdh_p256_ctx *ctx, const uint8_t sk[32], const uint8_t pk[64])
int	ocrypto_ecdh_p256_common_secret_iterate (ocrypto_ecdh_p256_ctx *ctx)
int	ocrypto_ecdh_p256_common_secret_final (ocrypto_ecdh_p256_ctx *ctx, uint8_t r[32])

Detailed Description

Elliptic curve Diffie-Hellman algorithm based on the NIST P-256 curve (aka secp256r1).

ECDH P-256 is a specific implementation of a key agreement protocol.

See also

NIST - SP 800-56A Rev. 3