TwofishDecryptCTR

Decrypts a variable length data stream in the CTR mode.

Syntax

IppStatus ippsTwofishDecryptCTR(const Ipp8u* pSrc, Ipp8u* pDst, int srcLen, const IppsTwofishSpec* pCtx, Ipp8u* pCtrValue, int ctrNumBitSize);

Parameters

pSrc	Pointer to the input ciphertext data stream.
pDst	Pointer to the resulting plaintext data stream of a variable length.
srcLen	Length of the plaintext data stream in bytes.
pCtx	Pointer to the IppsTwofishSpec context.
pCtrValue	Pointer to the counter data block.
ctrNumBitSize	Number of bits in the specific part of the counter to be incremented.

Description

This function is declared in the ippcp.h file. The function decrypts the input data stream of a variable length according to the CTR mode as specified in the [NIST SP 800-38A].

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.
ippStsLengthErr	Indicates an error condition if the output data stream length is less than or equal to zero.
ippStsCTRSizeErr	Indicates an error condition if the value of the ctrNumBitSize is illegal.
ippStsContextMatchErr	Indicates an error condition if the context parameter does not match the operation.