Developer Guide and Reference for Intel® Integrated Performance Primitives Cryptography
AESDecryptCTR
Decrypts a variable length data stream in the CTR mode.
Syntax
IppStatus ippsAESDecryptCTR(const Ipp8u* pSrc, Ipp8u* pDst, int srcLen,const IppsAESSpec* pCtx, Ipp8u* pCtrValue, int ctrNumBitSize);
Include Files
ippcp.h
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 IppsAESSpec context. | 
| pCtrValue | Pointer to the counter data block. | 
| ctrNumBitSize | Number of bits in the specific part of the counter to be incremented. | 
Description
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. |