HKDF.Extract Method

Namespace: Rebex.Security.Cryptography

Assembly: Rebex.Security.dll (version 7.0.9119)

Extract(HashingAlgorithmId, Byte[], Byte[])

HKDF Extract function according to section 2.2 of RFC 5869.

Declaration

public static byte[] Extract(HashingAlgorithmId hashingAlgorithmId, byte[] ikm, byte[] salt = null)

Parameters

Type	Name	Description
HashingAlgorithmId	hashingAlgorithmId	The hash algorithm for HMAC operations.
Byte[]	ikm	A byte array that contains input keying material. This is the 'IKM' parameter from RFC 5869.
Byte[]	salt	A byte array that contains the salt. When null or empty salt is specified, this method will use a zero-filled salt with size equal to the hash size of hashingAlgorithmId. This is the 'salt' parameter from RFC 5869.

Returns

Type	Description
Byte[]	A byte array that contains the pseudorandom key (the 'PRK' output from RFC 5869).

Exceptions

Type	Condition
ArgumentNullException	The ikm is null.
ArgumentException	The ikm is an empty array, or hashingAlgorithmId is not supported.

Extract(HashingAlgorithmId, ArraySegment<Byte>, ArraySegment<Byte>, ArraySegment<Byte>)

HKDF Extract function according to section 2.2 of RFC 5869.

Declaration

public static int Extract(HashingAlgorithmId hashingAlgorithmId, ArraySegment<byte> ikm, ArraySegment<byte> salt, ArraySegment<byte> prk)

Parameters

Type	Name	Description
HashingAlgorithmId	hashingAlgorithmId	The hash algorithm for HMAC operations.
ArraySegment<Byte>	ikm	An ArraySegment<T> that contains input keying material. This is the 'IKM' parameter from RFC 5869.
ArraySegment<Byte>	salt	An ArraySegment<T> that contains the salt. When an empty salt is specified, this method will use a zero-filled salt with size equal to the hash size of hashingAlgorithmId. This is the 'salt' parameter from RFC 5869.
ArraySegment<Byte>	prk	An ArraySegment<T> that will receive the pseudorandom key (the 'PRK' output from RFC 5869). The length of prk must be equal to or greater than the hash size of hashingAlgorithmId.

Returns

Type	Description
Int32	The number of bytes written to prk.

Exceptions

Type	Condition
ArgumentException	The ikm is empty, or hashingAlgorithmId is not supported.