package security;
import java.security.Key;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.spec.KeySpec;
import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;
import javax.crypto.spec.DESedeKeySpec;
import javax.crypto.spec.SecretKeySpec;
/**
* 加解密统一接口，支持流行的对称和非对称算法
* 目前可以使用3DES,AES，RSA进行加解密
* @author luis.chen
* @version $Id: EncryptUtil.java, v 0.1 2014年6月17日 上午11:08:28 luis.chen Exp $
*/
public class EncryptUtil {
public static void main
(String args
[]){ try {
System.
out.
println("开始使用AES加密...."); //使用AES加密
byte[] asKey = getDefaultKey(EncryptAlgorithm.AES);
String encStr
= testSymmEncry
(plainText,asKey,EncryptAlgorithm.
AES); System.
out.
println("AES加密之后:"+encStr
); //使用AES解密
String decStr
= testSymmDecry
(encStr,asKey,EncryptAlgorithm.
AES); System.
out.
println("AES解密之后:"+decStr
);
System.
out.
println("开始使用RSA加密....");
KeyPair kp
= getDefaultKeyPair
(EncryptAlgorithm.
RSA); String rsaEncStr
= testAsymmEncry
(plainText,kp.
getPublic(),EncryptAlgorithm.
RSAWithPadding); System.
out.
println("RSA加密之后:"+rsaEncStr
); //使用RSA解密
String desDecStr
= testAsymmDecry
(rsaEncStr,kp.
getPrivate(),EncryptAlgorithm.
RSAWithPadding); System.
out.
println("RSA解密之后:"+desDecStr
);
e.printStackTrace();
}
}
/*测试对称加密方法的应用场景类*/
byte[] encResult = encryt(EncryptStringUtils.getEncByteFromStr(plainText),key,alg);
String encStr
= EncryptStringUtils.
byte2hex(encResult
); return encStr;
}
/*测试非对称加密方法的应用场景类*/
// byte[] encResult = encryt(EncryptStringUtils.getEncByteFromStr(plainText),key,alg);
byte[] encResult = encryt(plainText.getBytes(),key,alg);
String encStr
= EncryptStringUtils.
byte2hex(encResult
); return encStr;
}
/*测试解密方法的应用场景类*/
byte[] decResult = decryt(EncryptStringUtils.getDecByteFromStr(ciperText),key,alg);
return decStr;
}
/*测试非对称解密方法的应用场景类*/
byte[] decResult = decryt(EncryptStringUtils.getDecByteFromStr(ciperText),key,alg);
return decStr;
}
/**
* 对称加密方法
* @param plainText 明文的16进制字节数组
* @param encrytKey 16进制的密钥数组
* @param alg 加密算法的枚举
* @return 加密结果，返回加密后的字节数组
* @throws Exception
* */
public static byte[] encryt
(byte[] plainText,
byte[] encrytKey,EncryptAlgorithm alg
) throws Exception{ Key k
= toKey
(encrytKey,alg
); return encryt(plainText,k,alg);
}
/**
* 非对称加密方法
* @param plainText 明文的16进制字节数组
* @param key 通过KeyPair获得的公钥
* @param alg 加密算法的枚举
* @return 加密结果，返回加密后的字节数组
* @throws Exception
* */
public static byte[] encryt
(byte[] plainText,
Key key,EncryptAlgorithm alg
) throws Exception{ Cipher cipher = Cipher.getInstance(alg.getAlgorithm());
cipher.init(Cipher.ENCRYPT_MODE, key);
return cipher.doFinal(plainText);
}
/**
* 对称加密解密方法
* @param ciperText 密文的16进制字节数组
* @param decrytKey 16进制的密钥数组
* @param alg 加密算法的枚举
* @return 解密结果，返回解密后的字节数组
* @throws Exception
* */
public static byte[] decryt
(byte[] ciperText,
byte[] decrytKey,EncryptAlgorithm alg
) throws Exception{ Key k
= toKey
(decrytKey,alg
); return decryt(ciperText,k,alg);
}
/**
* 非对称加密解密方法
* @param ciperText 密文的16进制字节数组
* @param key 通过keypair得到的非对称加密私钥
* @param alg 加密算法的枚举
* @return 解密结果，返回解密后的字节数组
* @throws Exception
* */
public static byte[] decryt
(byte[] ciperText,
Key key,EncryptAlgorithm alg
) throws Exception{ Cipher cipher = Cipher.getInstance(alg.getAlgorithm());
cipher.init(Cipher.DECRYPT_MODE, key);
return cipher.doFinal(ciperText);
}
/**
* 获取对称加密算法算法的密钥
* @param alg 加密算法枚举
* @return 16进制的密钥数组
* @throws
* */
public static byte[] getDefaultKey
(EncryptAlgorithm alg
) throws Exception{ KeyGenerator keygen = KeyGenerator.getInstance(alg.getAlgorithm());
SecretKey deskey = keygen.generateKey();
return deskey.getEncoded();
}
/**
* 获取非对称加密算法的密钥
* @param alg 加密算法枚举
* @return 16进制的密钥数组
* @throws
* */
//密钥位数
keyPairGen.initialize(1024);
//密钥对
KeyPair keyPair
= keyPairGen.
generateKeyPair(); return keyPair;
}
/**
* 通过key的字节数组和特定的算法得到用于加解密的密钥对象
* @param key 密钥数组
* @param alg 加解密算法的枚举
* @return KEY
* @throws Exception
*/
private static Key toKey
(byte[] key, EncryptAlgorithm alg
) throws Exception { SecretKeySpec spec = new SecretKeySpec(key,alg.getAlgorithm());
if(alg.getAlgorithm().indexOf("DES") > -1 ){
SecretKeyFactory keyFactory = null;
if("DES".equals(alg.getAlgorithm())){
desKey = new DESKeySpec(key);
keyFactory = SecretKeyFactory.getInstance(alg.getAlgorithm());
}
else{
desKey = new DESedeKeySpec(key);
keyFactory = SecretKeyFactory.getInstance(EncryptAlgorithm.ThreeDES.getAlgorithm());
}// 将DESKeySpec对象转换成SecretKey对象
SecretKey securekey = keyFactory.generateSecret(desKey);
return securekey;
}
return spec;
}
}