Example, Key agreement

The following example shows ...

 IKeyPairGenerator kpg =
 KeyPairGeneratorFactory.getInstance(Registry.DH_KPG);
 kpg.setup(new HashMap()); // use default values
 KeyPair kpA = kpg.generate();
 KeyPair kpB = kpg.generate();
 IKeyAgreementParty A = new DiffieHellmanSender();
 IKeyAgreementParty B = new DiffieHellmanReceiver();
 
 Map mapA = new HashMap();
 mapA.put(DiffieHellmanKeyAgreement.KA_DIFFIE_HELLMAN_OWNER_PRIVATE_KEY,
 kpA.getPrivate());
 Map mapB = new HashMap();
 mapB.put(DiffieHellmanKeyAgreement.KA_DIFFIE_HELLMAN_OWNER_PRIVATE_KEY,
 kpB.getPrivate());
 
 A.init(mapA);
 B.init(mapB);
 
 // (1) A -> B: g**x mod p
 OutgoingMessage out = A.processMessage(null);
 
 // (2) B -> A: g^^y mod p
 out = B.processMessage(new IncomingMessage(out.toByteArray()));
 
 byte[] k2 = B.getSharedSecret();
 
 // A computes the shared secret
 out = A.processMessage(new IncomingMessage(out.toByteArray()));
 
 byte[] k1 = A.getSharedSecret();