org.dromara.hutool.crypto.symmetric.Vigenere Maven / Gradle / Ivy
/*
* Copyright (c) 2013-2024 Hutool Team and hutool.cn
*
* 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 org.dromara.hutool.crypto.symmetric;
/**
* 维吉尼亚密码实现。
* 人们在恺撒移位密码的基础上扩展出多表密码，称为维吉尼亚密码。
* 算法实现来自：https://github.com/zhaorenjie110/SymmetricEncryptionAndDecryption
*
* @author looly,zhaorenjie110
* @since 4.4.1
*/
public class Vigenere {
/**
* 加密
*
* @param data 数据
* @param cipherKey 密钥
* @return 密文
*/
public static String encrypt(final CharSequence data, final CharSequence cipherKey) {
final int dataLen = data.length();
final int cipherKeyLen = cipherKey.length();
final char[] cipherArray = new char[dataLen];
for (int i = 0; i < dataLen / cipherKeyLen + 1; i++) {
for (int t = 0; t < cipherKeyLen; t++) {
if (t + i * cipherKeyLen < dataLen) {
final char dataChar = data.charAt(t + i * cipherKeyLen);
final char cipherKeyChar = cipherKey.charAt(t);
cipherArray[t + i * cipherKeyLen] = (char) ((dataChar + cipherKeyChar - 64) % 95 + 32);
}
}
}
return String.valueOf(cipherArray);
}
/**
* 解密
*
* @param data 密文
* @param cipherKey 密钥
* @return 明文
*/
public static String decrypt(final CharSequence data, final CharSequence cipherKey) {
final int dataLen = data.length();
final int cipherKeyLen = cipherKey.length();
final char[] clearArray = new char[dataLen];
for (int i = 0; i < dataLen; i++) {
for (int t = 0; t < cipherKeyLen; t++) {
if (t + i * cipherKeyLen < dataLen) {
final char dataChar = data.charAt(t + i * cipherKeyLen);
final char cipherKeyChar = cipherKey.charAt(t);
if (dataChar - cipherKeyChar >= 0) {
clearArray[t + i * cipherKeyLen] = (char) ((dataChar - cipherKeyChar) % 95 + 32);
} else {
clearArray[t + i * cipherKeyLen] = (char) ((dataChar - cipherKeyChar + 95) % 95 + 32);
}
}
}
}
return String.valueOf(clearArray);
}
}