com.github.davidcarboni.cryptolite

Class HashMac

java.lang.Object

com.github.davidcarboni.cryptolite.HashMac

public class HashMac
extends Object

Provides a simple way to generate a Hash MAC (HMAC) using "HmacSHA256".

Author:

David Carboni

Field Summary

Fields

Modifier and Type	Field and Description
static String	ALGORITHM The algorithm used for computing HMACs.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	HashMac(byte[] key, String algorithm) This constructor is protected so that, should you need a different algorithm (e.g.
	HashMac(SecretKey key) This constructor allows you to use a SecretKey to generate an HMAC.
	HashMac(String key) This constructor provides parity with PHP's hash_hmac("sha256", "message", "key") function.

Method Summary

Modifier and Type	Method and Description
String	digest(String message) Computes an HMAC for the given message, using the key passed to the constructor.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

ALGORITHM

public static final String ALGORITHM

The algorithm used for computing HMACs.

See Also:

Constant Field Values

Constructor Detail

HashMac

public HashMac(String key)

This constructor provides parity with PHP's hash_hmac("sha256", "message", "key") function.

Parameters:

key - An arbitrary String to use as a key.

HashMac

public HashMac(SecretKey key)

This constructor allows you to use a SecretKey to generate an HMAC. NB The Key.getEncoded() method of the key should return a suitable byte array. This is the case for keys generated/unwrapped using Cryptolite.

Parameters:

key - An key, whose Key.getEncoded() method will be called.

HashMac

protected HashMac(byte[] key,
                  String algorithm)

This constructor is protected so that, should you need a different algorithm (e.g. if you're integrating with a system that uses different crypto settings) it is possible to create a subclass with different settings.

Parameters:

key - A byte array to use as the key.

algorithm - This should normally be "HmacSHA256".

Method Detail

digest

public String digest(String message)

Computes an HMAC for the given message, using the key passed to the constructor.

Parameters:

message - The message.

Returns:

The HMAC value for the message and key.