RSA Security 5 manual AIECPubKey, Pointer to an Aecpublickey structure

AI_ECPubKey

AI_ECPubKey

Purpose:

This AI allows you to specify an EC public key and underlying EC parameters in order to build an acceleration table.

Type of information this allows you to use:

the encoding of an ANSI X9.62 Version 1 algorithm identifier that specifies an elliptic curve public key. An initialized AI_ECPubKeyBER or AI_ECPubKey algorithm object can be used as the input parameter ParameterInfoType when initializing an AI_ECBuildPubKeyAccelTable.

Format of info supplied to B_SetAlgorithmInfo:

pointer to an A_EC_PUBLIC_KEY structure:

typedef struct	{
A_EC_PARAMS curveParams;		/* the underlying elliptic curve parameters */
ITEM publicKey;			/* public component */
} A_EC_PUBLIC_KEY;
typedef struct	{
unsigned int	version;		/* implementation version */
unsigned int	fieldType;		/* indicates type of base field */
ITEM	fieldInfo;	/* The prime number if fieldType = FT_FP; */
	/* the basis polynomial if fieldType = FT_F2_POLYNOMIAL; */
	/* and the degree of the field if fieldType = FT_F2_ONB */
ITEM	coeffA;		/* elliptic curve coefficient */
ITEM	coeffB;		/* elliptic curve coefficient */
ITEM	base;		/* elliptic curve group generator */
ITEM	order;	/* order of subgroup’s generating element */
ITEM	cofactor;		/* the cofactor of the subgroup */
unsigned int	pointRepresentation;		/*not used */
			/* set to CI_NO_COMPRESS as a default */
unsigned int	fieldElementBits;		/* field element size in bits */
} A_EC_PARAMS;

Each ITEM supplies an integer in canonical format, where the ITEM’s data points to an unsigned byte array -- most significant byte first -- and the ITEM’s len gives its length. For all ITEM values except the public component (x) and the curve parameter base,

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