HKDF_extract

Computes the PRK, a pseudorandom key of HashLen bytes, from input keying material, salt, and hash method per the HKDF standard.

Syntax

IppStatus ippsHKDF_extract(const Ipp8u* ikm, int ikmLen, Ipp8u* prk, const Ipp8u* salt, int saltLen, const IppsHashMethod* pMethod);

Include Files

ippcp.h

Parameters

ikm	Pointer to the input keying material.
ikmLen	Length of the input keying material in bytes.
prk	Pointer to the output pseudorandom key of size HashLen bytes.
salt	Pointer to salt value.
saltLen	Length of salt value in bytes.
pMethod	Pointer to the hash method context.

Description

The function computes the output PRK pseudorandom key as a part of the Hashed Message Authentication Code (HMAC)-based key derivation function (HKDF) as specified in RFC 5869. The combination of functions ippsHKDF_extract() & ippsHKDF_expand() perform the equivalent combined function ippsHKDF().

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 hashLen < 0 or hashLen > MAX_HKDF_HASH_SIZE where MAX_HKDF_HASH_SIZE is the max hash size possible in the library.
ippsStsNotSupportedModeErr	Indicates hash method is not supported