HMAC_GetTag

Computes the current HMAC value of the processed part of the message.

Syntax

IppStatus ippsHMAC_GetTag(Ipp8u* pMD, int mdLen, const IppsHMACState* pCtx);

IppStatus ippsHMACGetTag_rmf(Ipp8u* pMD, int mdLen, const IppsHMACState_rmf* pCtx);

Include Files

ippcp.h

Parameters

pMD

Pointer to the authentication tag.

mdLen

The length of the tag (in bytes).

pCtx

Pointer to the IppsHMACState or IppsHMACState_rmf context.

Description

The function computes the message digest based on the current context as specified in [FIPS PUB 198]. A call to this function retains the possibility to update the digest.

Note

This function has a reduced memory footprint version. To learn more, see Reduced Memory Footprint Functions.

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 mdLen <1 or mdLen exceeds the maximal length of a particular digest.

ippStsContextMatchErr

Indicates an error condition if the context parameter does not match the operation.