Examples with DHKeyParameters com.github.zhenwei.core.crypto.params.DHKeyParameters used on opensource projects

Example 1 with DHKeyParameters

use of com.github.zhenwei.core.crypto.params.DHKeyParameters in project LinLong-Java by zhenwei1108.

the class IESCipher method engineDoFinal.

// Finalisation methods
public byte[] engineDoFinal(byte[] input, int inputOffset, int inputLen) throws IllegalBlockSizeException, BadPaddingException {
    if (inputLen != 0) {
        buffer.write(input, inputOffset, inputLen);
    }
    byte[] in = buffer.toByteArray();
    buffer.reset();
    // Convert parameters for use in IESEngine
    CipherParameters params = new IESWithCipherParameters(engineSpec.getDerivationV(), engineSpec.getEncodingV(), engineSpec.getMacKeySize(), engineSpec.getCipherKeySize());
    if (engineSpec.getNonce() != null) {
        params = new ParametersWithIV(params, engineSpec.getNonce());
    }
    DHParameters dhParams = ((DHKeyParameters) key).getParameters();
    byte[] V;
    if (otherKeyParameter != null) {
        try {
            if (state == Cipher.ENCRYPT_MODE || state == Cipher.WRAP_MODE) {
                engine.init(true, otherKeyParameter, key, params);
            } else {
                engine.init(false, key, otherKeyParameter, params);
            }
            return engine.processBlock(in, 0, in.length);
        } catch (Exception e) {
            throw new BadBlockException("unable to process block", e);
        }
    }
    if (state == Cipher.ENCRYPT_MODE || state == Cipher.WRAP_MODE) {
        // Generate the ephemeral key pair
        DHKeyPairGenerator gen = new DHKeyPairGenerator();
        gen.init(new DHKeyGenerationParameters(random, dhParams));
        EphemeralKeyPairGenerator kGen = new EphemeralKeyPairGenerator(gen, new KeyEncoder() {

            public byte[] getEncoded(AsymmetricKeyParameter keyParameter) {
                byte[] Vloc = new byte[(((DHKeyParameters) keyParameter).getParameters().getP().bitLength() + 7) / 8];
                byte[] Vtmp = BigIntegers.asUnsignedByteArray(((DHPublicKeyParameters) keyParameter).getY());
                if (Vtmp.length > Vloc.length) {
                    throw new IllegalArgumentException("Senders's public key longer than expected.");
                } else {
                    System.arraycopy(Vtmp, 0, Vloc, Vloc.length - Vtmp.length, Vtmp.length);
                }
                return Vloc;
            }
        });
        // Encrypt the buffer
        try {
            engine.init(key, params, kGen);
            return engine.processBlock(in, 0, in.length);
        } catch (Exception e) {
            throw new BadBlockException("unable to process block", e);
        }
    } else if (state == Cipher.DECRYPT_MODE || state == Cipher.UNWRAP_MODE) {
        // Decrypt the buffer
        try {
            engine.init(key, params, new DHIESPublicKeyParser(((DHKeyParameters) key).getParameters()));
            return engine.processBlock(in, 0, in.length);
        } catch (InvalidCipherTextException e) {
            throw new BadBlockException("unable to process block", e);
        }
    } else {
        throw new IllegalStateException("IESCipher not initialised");
    }
}