org.apache.xml.security.encryption.keys.content.derivedKey

Interface DerivationAlgorithm

All Known Implementing Classes:

ConcatKDF

public interface DerivationAlgorithm

Interface is supported by classes to implement key derivation algorithms.

Method Summary

Modifier and Type	Method and Description
byte[]	deriveKey(byte[] secret, byte[] otherInfo, int offset, long keyLength) Derives a key from the given secret and other info.
default byte[]	deriveKey(byte[] secret, byte[] otherInfo, long keyLength) Derives a key from the given secret and other info.

Method Detail

deriveKey

byte[] deriveKey(byte[] secret,
                 byte[] otherInfo,
                 int offset,
                 long keyLength)
          throws XMLSecurityException

Derives a key from the given secret and other info. The initial derived key is size of offset + keyLength.

Parameters:

secret - The "shared" secret to use for key derivation (e.g. the secret key)

otherInfo - as specified in [SP800-56A] the optional attributes: AlgorithmID, PartyUInfo, PartyVInfo, SuppPubInfo and SuppPrivInfo attributes are concatenated to form a bit string “OtherInfo” that is used with the key derivation function.

offset - the starting position in derived keying material of size: offset + keyLength

keyLength - The length of the key to derive

Returns:

The derived key

Throws:

XMLSecurityException - if something goes wrong during the key derivation

deriveKey

default byte[] deriveKey(byte[] secret,
                         byte[] otherInfo,
                         long keyLength)
                  throws XMLSecurityException

Derives a key from the given secret and other info.

Parameters:

secret - The "shared" secret to use for key derivation (e.g. the secret key)

otherInfo - as specified in [SP800-56A] the optional attributes: AlgorithmID, PartyUInfo, PartyVInfo, SuppPubInfo and SuppPrivInfo attributes are concatenated to form a bit string “OtherInfo” that is used with the key derivation function.

keyLength - The length of the key to derive

Returns:

The derived key

Throws:

XMLSecurityException - if something goes wrong during the key derivation