AES_XTSDecrypt¶

Decrypts a data buffer in the XTS mode.

Syntax¶

IppStatus ippsAES_XTSDecrypt(const Ipp8u* pSrc, Ipp8u* pDst, int bitSizeLen, const IppsAES_XTSSpec* pCtx, const Ipp8u* pTweak, int startCipherBlkNo);

ippcp.h

pSrc	Pointer to the input ciphertext data stream of variable length.
pDst	Pointer to the resulting plaintext data stream.
bitSizeLen	Length of the input buffer in bits.
pCtx	Pointer to the IppsAES_XTSSpec context.
pTweak	Pointer to the tweak vector assigned to the data unit being decrypted.
startCipherBlkNo	Number of the first block of the data unit.

The function decrypts the input ciphered data stream of a variable length in the XTS mode as specified in [IEEE P1619] and [NIST SP 800-38E].

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 bitSizeLen parameter value is less than 128.
ippStsBadArgErr	Indicates an error condition in the following cases: `startCipherBlkNo` value is less than zero. `startCipherBlkNo` value is greater than or equal to the number of the data unit blocks. `startCipherBlkNo×128+bitSizeLen` value is greater than size of the data unit in bits. size of the data unit in bits modulo 128 is zero and the `bitSizeLen` value modulo 128 is not zero. `bitSizeLen` value modulo 128 is zero and `startCipherBlkNo×128+bitSizeLen` value is not equal to size of the data unit in bits.
ippStsContextMatchErr	Indicates an error condition if the context parameter does not match the operation.