package one.video.streaming.oktp;

import java.math.BigInteger;
import java.security.InvalidAlgorithmParameterException;
import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.NoSuchAlgorithmException;
import javax.crypto.KeyAgreement;
import javax.crypto.spec.DHParameterSpec;
import javax.crypto.spec.DHPublicKeySpec;

public class DHCrypt {
    private final KeyPair _keyPair;
    private byte[] _sharedKey;
    private byte[] _peerKey;
    private static final BigInteger _prime;
    private static final BigInteger _generator;

    static {
        DHCrypt._prime = new BigInteger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
        DHCrypt._generator = new BigInteger("2");
    }

    DHCrypt() {
        super();
        try {
            KeyPairGenerator keyGen = KeyPairGenerator.getInstance("DH");
            keyGen.initialize(new DHParameterSpec(DHCrypt._prime, DHCrypt._generator));
            this._keyPair = keyGen.generateKeyPair();
            return;
        }
        catch(NoSuchAlgorithmException v0) {
        }
        catch(InvalidAlgorithmParameterException v0_1) {
        }

        throw new RuntimeException(((Throwable)v0_1));
    }

    public byte[] publicKey() {
        return this._keyPair.getPublic().getY().toByteArray();
    }

    public void computeSharedKey(byte[] peerKey) {
        this._peerKey = peerKey;
        try {
            KeyAgreement key = KeyAgreement.getInstance("DH");
            key.init(this._keyPair.getPrivate());
            key.doPhase(KeyFactory.getInstance("DH").generatePublic(new DHPublicKeySpec(new BigInteger(1, peerKey), DHCrypt._prime, DHCrypt._generator)), true);
            this._sharedKey = key.generateSecret();
        }
        catch(Exception e) {
            e.printStackTrace();
        }
    }

    public byte[] sharedKey() {
        return this._sharedKey;
    }

    public byte[] peerKey() {
        return this._peerKey;
    }
}