org.openid4java.association

Class DiffieHellmanSession

java.lang.Object

org.openid4java.association.DiffieHellmanSession

public class DiffieHellmanSession
extends Object

Author:

Marius Scurtescu, Johnny Bufu

Field Summary

Fields

Modifier and Type	Field and Description
static String	ALGORITHM
static long	DEFAULT_GENERATOR
static String	DEFAULT_GENERATOR_BASE64
static String	DEFAULT_MODULUS_BASE64
static String	DEFAULT_MODULUS_HEX
static String	H_ALGORITHM_SHA1
static String	H_ALGORITHM_SHA256

Method Summary

Methods

Modifier and Type	Method and Description
static DiffieHellmanSession	create(AssociationSessionType type, DHParameterSpec dhParameterSpec)
static DiffieHellmanSession	create(AssociationSessionType type, String modulusBase64, String generatorBase64)
byte[]	decryptMacKey(String encMacKeyBase64, String serverPublicKeyBase64) Decrypts the association AMC key.
String	encryptMacKey(byte[] macKey, String consumerPublicKeyBase64) Encrypts the association MAC key.
protected static KeyPair	generateKeyPair(DHParameterSpec dhSpec)
static DHParameterSpec	generateRandomParameter(int primeSize, int keySize)
static DHParameterSpec	getDefaultParameter()
protected byte[]	getDigestedZZ(String otherPublicKeyBase64)
String	getGenerator() Gets the generator for the Diffie-Hellman key echange.
String	getModulus() Gets the modulus for the Diffie-Hellman key echange.
protected DHPrivateKey	getPrivateKey()
String	getPublicKey() Get the Diffie-Hellman public key.
AssociationSessionType	getType()
static boolean	isDhSha1Supported()
static boolean	isDhSha256Supported()
static boolean	isDhShaSupported(String shaAlgorithm)
static boolean	isDhSupported(AssociationSessionType type)
protected static String	publicKeyToString(DHPublicKey publicKey)
protected DHPublicKey	stringToPublicKey(String publicKeyBase64)
String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_MODULUS_HEX

public static final String DEFAULT_MODULUS_HEX

See Also:

Constant Field Values

DEFAULT_MODULUS_BASE64

public static final String DEFAULT_MODULUS_BASE64

See Also:

Constant Field Values

DEFAULT_GENERATOR

public static final long DEFAULT_GENERATOR

See Also:

Constant Field Values

DEFAULT_GENERATOR_BASE64

public static final String DEFAULT_GENERATOR_BASE64

See Also:

Constant Field Values

ALGORITHM

public static final String ALGORITHM

See Also:

Constant Field Values

H_ALGORITHM_SHA1

public static final String H_ALGORITHM_SHA1

See Also:

Constant Field Values

H_ALGORITHM_SHA256

public static final String H_ALGORITHM_SHA256

See Also:

Constant Field Values

Method Detail

toString

public String toString()

Overrides:

toString in class Object

create

public static DiffieHellmanSession create(AssociationSessionType type,
                          String modulusBase64,
                          String generatorBase64)
                                   throws AssociationException

Throws:

AssociationException

create

public static DiffieHellmanSession create(AssociationSessionType type,
                          DHParameterSpec dhParameterSpec)
                                   throws AssociationException

Throws:

AssociationException

getDefaultParameter

public static DHParameterSpec getDefaultParameter()

generateRandomParameter

public static DHParameterSpec generateRandomParameter(int primeSize,
                                      int keySize)

generateKeyPair

protected static KeyPair generateKeyPair(DHParameterSpec dhSpec)

getType

public AssociationSessionType getType()

getModulus

public String getModulus()

Gets the modulus for the Diffie-Hellman key echange. This is the value passed in the openid.dh_modulus association request parameter.

Returns:

The base 64 encoded two's-complement representation of the modulus: base64(btwoc(p))

getGenerator

public String getGenerator()

Gets the generator for the Diffie-Hellman key echange. This is the value passed in the openid.dh_gen association request parameter.

Returns:

The base 64 encoded two's-complement representation of the generator: base64(btwoc(g))

getPublicKey

public String getPublicKey()

Get the Diffie-Hellman public key. This is the value passed in the openid.dh_consumer_public association request parameter and the value passed in the openid.dh_server_public association response parameter.

Returns:

The base 64 encoded two's-complement representation of the public key: base64(btwoc(g ^ x mod p))

getPrivateKey

protected DHPrivateKey getPrivateKey()

encryptMacKey

public String encryptMacKey(byte[] macKey,
                   String consumerPublicKeyBase64)
                     throws AssociationException

Encrypts the association MAC key. The encryption takes palce on the server side (aka OP). This is the value passed in the openid.enc_mac_key association response parameter.

Parameters:

macKey - The MAC key in binary format.

consumerPublicKeyBase64 - The base 64 encoding of the consumer Diffie-Hellman public key. This is the value passed in the openid.dh_consumer_public association request parameter.

Returns:

The base 64 encoded two's-complement representation of the encrypted mac key: base64(H(btwoc(g ^ (xa * xb) mod p)) XOR MAC)

Throws:

AssociationException - if the lengths of the mac key and digest of Diffie-Hellman shared secred do not match.

decryptMacKey

public byte[] decryptMacKey(String encMacKeyBase64,
                   String serverPublicKeyBase64)
                     throws AssociationException

Decrypts the association AMC key. The decryption takes palce on the consumer side (aka RP).

Parameters:

encMacKeyBase64 - The base 64 encoded two's-complement representation of the encrypted mac key: base64(H(btwoc(g ^ (xa * xb) mod p)) XOR MAC). This is the value passed in the openid.enc_mac_key association response parameter.

serverPublicKeyBase64 - The base 64 encoding of the server Diffie-Hellman public key. This is the value passed in the openid.dh_server_public association response parameter.

Returns:

The MAC key in binary format.

Throws:

AssociationException - if the lengths of the encrypted mac key and digest of Diffie-Hellman shared secret do not match.

publicKeyToString

protected static String publicKeyToString(DHPublicKey publicKey)

stringToPublicKey

protected DHPublicKey stringToPublicKey(String publicKeyBase64)

getDigestedZZ

protected byte[] getDigestedZZ(String otherPublicKeyBase64)

isDhSupported

public static boolean isDhSupported(AssociationSessionType type)

isDhShaSupported

public static boolean isDhShaSupported(String shaAlgorithm)

isDhSha1Supported

public static boolean isDhSha1Supported()

isDhSha256Supported

public static boolean isDhSha256Supported()