/**
* Copyright (c) 2005-2012 springside.org.cn
*
* Licensed under the Apache License, Version 2.0 (the "License");
*/
package com.github.dactiv.common.utils;
import java.security.GeneralSecurityException;
import java.security.SecureRandom;
import java.util.Arrays;
import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.Mac;
import javax.crypto.SecretKey;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
/**
* 支持HMAC-SHA1消息签名 及 DES/AES对称加密的工具类.
*
* 支持Hex与Base64两种编码方式.
*
* @author calvin
*/
public class CryptoUtils {
private static final String AES = "AES";
private static final String AES_CBC = "AES/CBC/PKCS5Padding";
private static final String HMACSHA1 = "HmacSHA1";
private static final int DEFAULT_HMACSHA1_KEYSIZE = 160; // RFC2401
private static final int DEFAULT_AES_KEYSIZE = 128;
private static final int DEFAULT_IVSIZE = 16;
private static SecureRandom random = new SecureRandom();
// -- HMAC-SHA1 funciton --//
/**
* 使用HMAC-SHA1进行消息签名, 返回字节数组,长度为20字节.
*
* @param input 原始输入字符数组
* @param key HMAC-SHA1密钥
*/
public static byte[] hmacSha1(byte[] input, byte[] key) {
try {
SecretKey secretKey = new SecretKeySpec(key, HMACSHA1);
Mac mac = Mac.getInstance(HMACSHA1);
mac.init(secretKey);
return mac.doFinal(input);
} catch (GeneralSecurityException e) {
throw ExceptionUtils.unchecked(e);
}
}
/**
* 校验HMAC-SHA1签名是否正确.
*
* @param expected 已存在的签名
* @param input 原始输入字符串
* @param key 密钥
*/
public static boolean isMacValid(byte[] expected, byte[] input, byte[] key) {
byte[] actual = hmacSha1(input, key);
return Arrays.equals(expected, actual);
}
/**
* 生成HMAC-SHA1密钥,返回字节数组,长度为160位(20字节).
* HMAC-SHA1算法对密钥无特殊要求, RFC2401建议最少长度为160位(20字节).
*/
public static byte[] generateHmacSha1Key() {
try {
KeyGenerator keyGenerator = KeyGenerator.getInstance(HMACSHA1);
keyGenerator.init(DEFAULT_HMACSHA1_KEYSIZE);
SecretKey secretKey = keyGenerator.generateKey();
return secretKey.getEncoded();
} catch (GeneralSecurityException e) {
throw ExceptionUtils.unchecked(e);
}
}
// -- AES funciton --//
/**
* 使用AES加密原始字符串.
*
* @param input 原始输入字符数组
* @param key 符合AES要求的密钥
*/
public static byte[] aesEncrypt(byte[] input, byte[] key) {
return aes(input, key, Cipher.ENCRYPT_MODE);
}
/**
* 使用AES加密原始字符串.
*
* @param input 原始输入字符数组
* @param key 符合AES要求的密钥
* @param iv 初始向量
*/
public static byte[] aesEncrypt(byte[] input, byte[] key, byte[] iv) {
return aes(input, key, iv, Cipher.ENCRYPT_MODE);
}
/**
* 使用AES解密字符串, 返回原始字符串.
*
* @param input Hex编码的加密字符串
* @param key 符合AES要求的密钥
*/
public static String aesDecrypt(byte[] input, byte[] key) {
byte[] decryptResult = aes(input, key, Cipher.DECRYPT_MODE);
return new String(decryptResult);
}
/**
* 使用AES解密字符串, 返回原始字符串.
*
* @param input Hex编码的加密字符串
* @param key 符合AES要求的密钥
* @param iv 初始向量
*/
public static String aesDecrypt(byte[] input, byte[] key, byte[] iv) {
byte[] decryptResult = aes(input, key, iv, Cipher.DECRYPT_MODE);
return new String(decryptResult);
}
/**
* 使用AES加密或解密无编码的原始字节数组, 返回无编码的字节数组结果.
*
* @param input 原始字节数组
* @param key 符合AES要求的密钥
* @param mode Cipher.ENCRYPT_MODE 或 Cipher.DECRYPT_MODE
*/
private static byte[] aes(byte[] input, byte[] key, int mode) {
try {
SecretKey secretKey = new SecretKeySpec(key, AES);
Cipher cipher = Cipher.getInstance(AES);
cipher.init(mode, secretKey);
return cipher.doFinal(input);
} catch (GeneralSecurityException e) {
throw ExceptionUtils.unchecked(e);
}
}
/**
* 使用AES加密或解密无编码的原始字节数组, 返回无编码的字节数组结果.
*
* @param input 原始字节数组
* @param key 符合AES要求的密钥
* @param iv 初始向量
* @param mode Cipher.ENCRYPT_MODE 或 Cipher.DECRYPT_MODE
*/
private static byte[] aes(byte[] input, byte[] key, byte[] iv, int mode) {
try {
SecretKey secretKey = new SecretKeySpec(key, AES);
IvParameterSpec ivSpec = new IvParameterSpec(iv);
Cipher cipher = Cipher.getInstance(AES_CBC);
cipher.init(mode, secretKey, ivSpec);
return cipher.doFinal(input);
} catch (GeneralSecurityException e) {
throw ExceptionUtils.unchecked(e);
}
}
/**
* 生成AES密钥,返回字节数组, 默认长度为128位(16字节).
*/
public static byte[] generateAesKey() {
return generateAesKey(DEFAULT_AES_KEYSIZE);
}
/**
* 生成AES密钥,可选长度为128,192,256位.
*/
public static byte[] generateAesKey(int keysize) {
try {
KeyGenerator keyGenerator = KeyGenerator.getInstance(AES);
keyGenerator.init(keysize);
SecretKey secretKey = keyGenerator.generateKey();
return secretKey.getEncoded();
} catch (GeneralSecurityException e) {
throw ExceptionUtils.unchecked(e);
}
}
/**
* 生成随机向量,默认大小为cipher.getBlockSize(), 16字节.
*/
public static byte[] generateIV() {
byte[] bytes = new byte[DEFAULT_IVSIZE];
random.nextBytes(bytes);
return bytes;
}
}