Data Structures
struct	CRYS_ECMONT_ScalrMultTempBuff_t
struct	CRYS_ECMONT_TempBuff_t

Macros
#define	CRYS_ECMONT_MOD_SIZE_IN_BITS 255U
#define	CRYS_ECMONT_MOD_SIZE_IN_32BIT_WORDS (( CRYS_ECMONT_MOD_SIZE_IN_BITS + SASI_BITS_IN_32BIT_WORD - 1) / SASI_BITS_IN_32BIT_WORD )
#define	CRYS_ECMONT_MOD_SIZE_IN_BYTES (( CRYS_ECMONT_MOD_SIZE_IN_BITS + SASI_BITS_IN_32BIT_WORD - 1) / sizeof(uint32_t))
#define	CRYS_ECMONT_SCALARBYTES ( CRYS_ECMONT_MOD_SIZE_IN_32BIT_WORDS * SASI_32BIT_WORD_SIZE )
#define	CRYS_ECMONT_SCALARMULTBYTES ( CRYS_ECMONT_MOD_SIZE_IN_32BIT_WORDS * SASI_32BIT_WORD_SIZE )
#define	CRYS_ECMONT_SEEDBYTES ( CRYS_ECMONT_MOD_SIZE_IN_32BIT_WORDS * SASI_32BIT_WORD_SIZE )

Enumerations
enum	CRYS_ECMONT_DomainId_t { CRYS_ECMONT_DOMAIN_CURVE_25519 , CRYS_ECMONT_DOMAIN_OFF_MODE , CRYS_ECMONT_DOMAIN_LAST = 0x7FFFFFFF }

Functions
CRYSError_t	CRYS_ECMONT_Scalarmult (uint8_t *pResPoint, size_t *pResPointSize, const uint8_t *pScalar, size_t scalarSize, const uint8_t *pInPoint, size_t inPointSize, CRYS_ECMONT_TempBuff_t *pEcMontTempBuff)
	The function performs EC Montgomery (Curve25519) scalar multiplication: resPoint = scalar * point. More...
CRYSError_t	CRYS_ECMONT_ScalarmultBase (uint8_t *pResPoint, size_t *pResPointSize, const uint8_t *pScalar, size_t scalarSize, CRYS_ECMONT_TempBuff_t *pEcMontTempBuff)
	The function performs EC Montgomery (Curve25519) scalar multiplication of base point: res = scalar * base_point. More...
CRYSError_t	CRYS_ECMONT_KeyPair (uint8_t *pPublKey, size_t *pPublKeySize, uint8_t *pSecrKey, size_t *pSecrKeySize, void *pRndState, SaSiRndGenerateVectWorkFunc_t rndGenerateVectFunc, CRYS_ECMONT_TempBuff_t *pEcMontTempBuff)
	The function randomly generates private and public keys for Montgomery Curve25519. More...
CRYSError_t	CRYS_ECMONT_SeedKeyPair (uint8_t *pPublKey, size_t *pPublKeySize, uint8_t *pSecrKey, size_t *pSecrKeySize, const uint8_t *pSeed, size_t seedSize, CRYS_ECMONT_TempBuff_t *pEcMontTempBuff)
	The function generates private and public keys for Montgomery algorithms. More...

Detailed Description

Note

Implemented algorithms according to Montgomery elliptic curves cryptography, developed by Daniel J.Bernstein etc.

Macro Definition Documentation

#define CRYS_ECMONT_MOD_SIZE_IN_32BIT_WORDS   (( CRYS_ECMONT_MOD_SIZE_IN_BITS + SASI_BITS_IN_32BIT_WORD - 1) / SASI_BITS_IN_32BIT_WORD )

EC Montgomery modulus size in words.

#define CRYS_ECMONT_MOD_SIZE_IN_BITS   255U

EC Montgomery curve25519 modulus size in bits, words and bytes

EC Montgomery modulus size in bits.

#define CRYS_ECMONT_MOD_SIZE_IN_BYTES   (( CRYS_ECMONT_MOD_SIZE_IN_BITS + SASI_BITS_IN_32BIT_WORD - 1) / sizeof(uint32_t))

EC Montgomery modulus size in bytes.

#define CRYS_ECMONT_SCALARBYTES   ( CRYS_ECMONT_MOD_SIZE_IN_32BIT_WORDS * SASI_32BIT_WORD_SIZE )

Constant sizes of special EC_MONT buffers and arrays

EC Montgomery scalar size in bytes.

#define CRYS_ECMONT_SCALARMULTBYTES   ( CRYS_ECMONT_MOD_SIZE_IN_32BIT_WORDS * SASI_32BIT_WORD_SIZE )

EC Montgomery scalar multiplication size in bytes.

#define CRYS_ECMONT_SEEDBYTES   ( CRYS_ECMONT_MOD_SIZE_IN_32BIT_WORDS * SASI_32BIT_WORD_SIZE )

EC Montgomery scalar seed size in bytes.

Enumeration Type Documentation

enum CRYS_ECMONT_DomainId_t

EC Montgomery domains ID-s enumerator.

Enumerator
CRYS_ECMONT_DOMAIN_CURVE_25519	EC Curve25519.
CRYS_ECMONT_DOMAIN_OFF_MODE	EC Montgomery last domain.
CRYS_ECMONT_DOMAIN_LAST	Reserved.

Function Documentation

CRYSError_t CRYS_ECMONT_KeyPair	(	uint8_t *	pPublKey ,
		size_t *	pPublKeySize ,
		uint8_t *	pSecrKey ,
		size_t *	pSecrKeySize ,
		void *	pRndState ,
		SaSiRndGenerateVectWorkFunc_t	rndGenerateVectFunc ,
		CRYS_ECMONT_TempBuff_t *	pEcMontTempBuff
	)

The function randomly generates private and public keys for Montgomery Curve25519.

Note

• All byte arrays are in LE order of bytes, i.e. LS byte is on the left most place.
• LS and MS bits of the Secret key are set according to EC Montgomery scalar mult. algorithm: secrKey[0] &= 248; secrKey[31] &= 127; secrKey[31] |= 64;

Returns

CRYS_OK on success,

A non-zero value on failure as defined crys_ec_mont_edw_error.h or crys_rnd_error.h.

Parameters

[out]	pPublKey	Pointer to the public key.
[in,out]	pPublKeySize	Pointer to the size of the public key in bytes. In - the size of the buffer must be at least EC order size (for curve25519 - 32 bytes); Out - the actual size.
[out]	pSecrKey	Pointer to the secret key, including.
[in,out]	pSecrKeySize	Pointer to the size of buffer for the secret key in bytes - must be at least EC order size (for curve25519 - 32 bytes).
[in,out]	pRndState	Pointer to the RND state structure.
[in]	rndGenerateVectFunc	Pointer to the random vector generation function.
[in]	pEcMontTempBuff	Pointer to the temp buffer, for internal use.

CRYSError_t CRYS_ECMONT_Scalarmult	(	uint8_t *	pResPoint ,
		size_t *	pResPointSize ,
		const uint8_t *	pScalar ,
		size_t	scalarSize ,
		const uint8_t *	pInPoint ,
		size_t	inPointSize ,
		CRYS_ECMONT_TempBuff_t *	pEcMontTempBuff
	)

The function performs EC Montgomery (Curve25519) scalar multiplication: resPoint = scalar * point.

Returns

CRYS_OK on success,

A non-zero value on failure as defined crys_ec_mont_edw_error.h.

Parameters

[out]	pResPoint	Pointer to the public (secret) key.
[in,out]	pResPointSize	Pointer to the size of the public key in bytes. In - the size of the buffer. must be at least EC modulus size (for curve25519 - 32 bytes). Out - the actual size.
[in]	pScalar	Pointer to the secret (private) key.
[in]	scalarSize	Pointer to the size of the secret key in bytes; must be equal to EC order size (for curve25519 - 32 bytes).
[in]	pInPoint	Pointer to the input point (compressed).
[in]	inPointSize	Size of the point - must be equal to CRYS_ECMONT_MOD_SIZE_IN_BYTES.
[in]	pEcMontTempBuff	Pointer to temp buffer, for internal use.

CRYSError_t CRYS_ECMONT_ScalarmultBase	(	uint8_t *	pResPoint ,
		size_t *	pResPointSize ,
		const uint8_t *	pScalar ,
		size_t	scalarSize ,
		CRYS_ECMONT_TempBuff_t *	pEcMontTempBuff
	)

The function performs EC Montgomery (Curve25519) scalar multiplication of base point: res = scalar * base_point.

   Note: all byte arrays have LE order of bytes, i.e. LS byte is on left most place.

Returns

CRYS_OK on success,

A non-zero value on failure as defined crys_ec_mont_edw_error.h.

Parameters

[out]	pResPoint	Pointer to the public (secret) key.
[in,out]	pResPointSize	Pointer to the size of the public key in bytes. In - the size of buffer must be at least EC modulus size (for curve25519 - 32 bytes); Out - the actual size.
[in]	pScalar	Pointer to the secret (private) key.
[in]	scalarSize	Pointer to the size of the scalar in bytes - must be equal to EC order size (for curve25519 - 32 bytes).
[in]	pEcMontTempBuff	Pointer to temp buffer, for internal use.

CRYSError_t CRYS_ECMONT_SeedKeyPair	(	uint8_t *	pPublKey ,
		size_t *	pPublKeySize ,
		uint8_t *	pSecrKey ,
		size_t *	pSecrKeySize ,
		const uint8_t *	pSeed ,
		size_t	seedSize ,
		CRYS_ECMONT_TempBuff_t *	pEcMontTempBuff
	)

The function generates private and public keys for Montgomery algorithms.

   The generation performed using given seed.

Returns

CRYS_OK on success,

A non-zero value on failure as defined crys_ec_mont_edw_error.h or crys_hash_error.h.

Parameters

[out]	pPublKey	Pointer to the public (secret) key.
[in,out]	pPublKeySize	Pointer to the size of the public key in bytes. In - the size of buffer must be at least EC order size (for curve25519 - 32 bytes); Out - the actual size.
[out]	pSecrKey	Pointer to the secret (private) key.
[in,out]	pSecrKeySize	Pointer to the size of the secret key in bytes In - the size of buffer must be at least EC order size (for curve25519 - 32 bytes); Out - the actual size.
[in]	pSeed	Pointer to the given seed - 32 bytes.
[in]	seedSize	Size of the seed in bytes (must be equal to CRYS_ECMONT_SEEDBYTES).
[in]	pEcMontTempBuff	Pointer to a temp buffer, for internal use.