com.github.flysium.io.yew.common.crypto.AbstractSymmetric Maven / Gradle / Ivy

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/*
 * Copyright 2018-2025 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.github.flysium.io.yew.common.crypto;

import com.github.flysium.io.yew.common.crypto.support.CryptoUtil;
import java.security.InvalidAlgorithmParameterException;
import java.security.InvalidKeyException;
import java.security.Provider;
import java.security.spec.AlgorithmParameterSpec;
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.SecretKey;
import javax.crypto.spec.IvParameterSpec;

/**
 * Symmetric encryption and decryption algorithm
 *
 * @author Sven Augustus
 * @version 1.0
 * @since JDK 1.7
 */
public abstract class AbstractSymmetric extends AbstractCryptoSpi {

	/**
	 * Symmetric secret
	 */
	protected SecretKey secretKey = null;
	private static final int IV_LENGTH = 16;

	public AbstractSymmetric(String algorithm, Provider provider, String transforms) {
		super(algorithm, provider, transforms);
	}

	@Override
	public byte[] getSecret() {
		return secretKey.getEncoded();
	}

	@Override
	public void setAlgorithmParameterSpec(AlgorithmParameterSpec spec) {
		if (spec == null) {
			return;
		}
		if (spec instanceof IvParameterSpec) {
			byte[] iv = ((IvParameterSpec) spec).getIV();
			if (iv == null || iv.length != IV_LENGTH) {
				throw new IllegalStateException(
						"Invalid iv size (" + (iv == null ? 0 : iv.length) + " bits)");
			}
		}
		super.setAlgorithmParameterSpec(spec);
	}

	@Override
	public void generateKey(int keyLength) {
		this.secretKey = CryptoUtil.generateKey(keyLength, algorithm, provider);
	}

	@Override
	public byte[] encrypt(byte[] plainText) {
		Cipher cipher = getCipher();

		try {
			if (cipher != null) {
				if (algorithmParameterSpec != null) {
					cipher.init(Cipher.ENCRYPT_MODE, this.secretKey, algorithmParameterSpec);
				} else {
					cipher.init(Cipher.ENCRYPT_MODE, this.secretKey);
				}

				return doFinal(cipher, Cipher.ENCRYPT_MODE, plainText);
			}
		} catch (InvalidKeyException | InvalidAlgorithmParameterException e) {
			fail(e);
		}
		return new byte[0];
	}

	@Override
	public byte[] decrypt(byte[] cipherText) {
		Cipher cipher = getCipher();
		try {
			if (cipher != null) {
				if (algorithmParameterSpec != null) {
					cipher.init(Cipher.DECRYPT_MODE, this.secretKey, algorithmParameterSpec);
				} else {
					cipher.init(Cipher.DECRYPT_MODE, this.secretKey);
				}

				return doFinal(cipher, Cipher.DECRYPT_MODE, cipherText);
			}
		} catch (InvalidKeyException | InvalidAlgorithmParameterException e) {
			fail(e);
		}
		return new byte[0];
	}

	protected byte[] doFinal(Cipher cipher, int mode, byte[] input) {
		try {
			return cipher.doFinal(input);
		} catch (IllegalBlockSizeException | BadPaddingException e) {
			fail(e);
		}
		return new byte[0];
	}

}