ECCBPublicKey

Computes a public key from the given private key of the elliptic cryptosystem over GF(2^m).

Syntax

IppStatus ippsECCBPublicKey(const IppsBigNumState* pPrivate, IppsECCBPoint* pPublic, IppsECCBState* pECC);

Parameters

pPrivate	Pointer to the private key `privKey`.
pPublic	Pointer to the public key `pubKey`.
pECC	Pointer to the context of the elliptic cryptosystem.

Description

This function is declared in the ippcp.h file.

The function computes the public key pubKey from the given private key privKey of the elliptic cryptosystem over a binary finite field GF(2^m).

The private key privKey is a number that lies in the range of [1, n-1] where n is the order of the elliptic curve base point. The public key pubKey is an elliptic curve point such that pubKey = privKey · G, where G is the base point of the elliptic curve.

The context of the point pubKey as an elliptic curve point must be created by using the functions ECCBPointGetSize and ECCBPointInit.

The elliptic curve domain parameters must be hitherto defined by one of the functions: ECCBSet or ECCBSetStd.

Return Values

ippStsNoErr	Indicates no error. Any other value indicates an error or warning.
ippStsNullPtrErr	Indicates an error condition if any of the specified pointers is NULL.
ippStsContextMatchErr	Indicates an error condition if one of the contexts pointed by pPrivate, pPublic, or pECC is not valid.
ippStsIvalidPrivateKey	Indicates an error condition if the value of the private key falls outside the range of [1, n-1].