ippsHashDRBG_EntropyInputCtxInit

Initializes the Entropy input context.

Syntax

IppStatus ippsHashDRBG_EntropyInputCtxInit(IppsHashDRBG_EntropyInputCtx* pEntrInputCtx,
                                           const int entrInputBufBitsLen,
                                           IppEntropyInputSupplier getEntropyInput);

Include Files

ippcp.h

Parameters

pEntrInputCtx	Pointer to the Entropy input context.
entrInputBufBitsLen	The length of the buffer containing the entropy input and the nonce.
getEntropyInput	Callback function for supplying the entropy input, providing both an entropy input and a nonce during instantiation, and an entropy input during reseeding or whenever prediction resistance is requested. The callback function must have the following signature: IppStatus _STDCALL getEntropyInput(Ipp8u* pEntropyInput, int* pEntropyInputBitsLen, const int minEntropyInBits, const int maxBitsLen, const int predictionResistanceRequest). pEntropyInput is a pointer to a byte string containing at least minEntropyInBits bits of entropy. pEntropyInputBitsLen is the entropy input buffer length in bits. minEntropyInBits and maxBitsLen is the minimum and maximum number bits of the entropy input. predictionResistanceRequest parameter indicates whether or not prediction resistance is to be provided during the request. Refer to the NIST SP 800-90C to figure out more about Sources of Randomness.

Description

The function initializes the IppsHashDRBG_EntropyInputCtx which encapsulates objects necessary for entropy input and nonce generation during the Hash DRBG operations.

Return Values

ippStsNoErr	Indicates no error. All single operations executed without errors. Any other value indicates an error.
ippStsNullPtrErr	pEntrInputCtx is a NULL pointer.
ippStsOutOfRangeErr	entrInputBufBitsLen < 1.