android-templates/src/main/java/ru/touchin/templates/CryptoUtils.java

81 lines
2.9 KiB
Java

/*
* Copyright (c) 2016 Touch Instinct
*
* This file is part of RoboSwag library.
*
* 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 ru.touchin.templates;
import androidx.annotation.NonNull;
import com.tozny.crypto.android.AesCbcWithIntegrity;
import java.nio.charset.Charset;
import java.security.GeneralSecurityException;
import ru.touchin.roboswag.core.utils.ShouldNotHappenException;
/**
* Created by Gavriil Sitnikov on 30/08/2016.
* Utility class that is providing common methods related to cryptography.
*/
public final class CryptoUtils {
/**
* Just encrypts bytes by key in good way.
* To decrypt them use {@link #simpleDecryptBytes(byte[], String)}.
* Dependency needed: compile 'com.scottyab:aes-crypto:+'.
*
* @param bytesToDecrypt Bytes to encrypt;
* @param keyString Encryption key;
* @return Encrypted bytes.
*/
@NonNull
public static byte[] simpleEncryptBytes(@NonNull final byte[] bytesToDecrypt, @NonNull final String keyString) {
try {
final AesCbcWithIntegrity.SecretKeys key = AesCbcWithIntegrity.keys(keyString);
final AesCbcWithIntegrity.CipherTextIvMac cipherTextIvMac = AesCbcWithIntegrity.encrypt(bytesToDecrypt, key);
return cipherTextIvMac.toString().getBytes(Charset.forName("UTF-8"));
} catch (final GeneralSecurityException exception) {
throw new ShouldNotHappenException(exception);
}
}
/**
* Just decrypts bytes which are encrypted by {@link #simpleEncryptBytes(byte[], String)}.
* Dependency needed: compile 'com.scottyab:aes-crypto:+'.
*
* @param encryptedBytes Bytes to decrypt;
* @param keyString Encryption key;
* @return Encrypted bytes.
*/
@NonNull
public static byte[] simpleDecryptBytes(@NonNull final byte[] encryptedBytes, @NonNull final String keyString) {
try {
final AesCbcWithIntegrity.SecretKeys key = AesCbcWithIntegrity.keys(keyString);
final AesCbcWithIntegrity.CipherTextIvMac cipherTextIvMac
= new AesCbcWithIntegrity.CipherTextIvMac(new String(encryptedBytes, Charset.forName("UTF-8")));
return AesCbcWithIntegrity.decrypt(cipherTextIvMac, key);
} catch (final GeneralSecurityException exception) {
throw new ShouldNotHappenException(exception);
}
}
private CryptoUtils() {
}
}