关于android的des算法代码

import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;
import javax.crypto.spec.IvParameterSpec;
import android.util.Base64;
import java.security.Key;
import java.security.spec.AlgorithmParameterSpec;
import javax.crypto.Cipher;

public class DesUtils {

public static final String ALGORITHM_DES = "DES/CBC/PKCS5Padding";

/**
* 解密.
* @param key
* @param data
* @return
* @throws Exception
*/
public static String decode(String key, String data) {
byte[] datas;
String value = null;
try {
if (System.getProperty("os.name") != null
&& (System.getProperty("os.name").equalsIgnoreCase("sunos") || System
.getProperty("os.name").equalsIgnoreCase("linux"))) {
datas = decode(key, Base64.decode(data, 0));
} else {
datas = decode(key, Base64.decode(data, 0));
}
value = new String(datas);
} catch (Exception e) {
value = "";
}
return value;
}

/**
* DES算法，解密
* @param data 待解密字符串
* @param key 解密私钥，长度不能够小于8位
* @return 解密后的字节数组
* @throws Exception 异常
*/
private static byte[] decode(String key, byte[] data) throws Exception {
try {
DESKeySpec dks = new DESKeySpec(key.getBytes());
SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
// key的长度不能够小于8位字节
Key secretKey = keyFactory.generateSecret(dks);
Cipher cipher = Cipher.getInstance(ALGORITHM_DES);
IvParameterSpec iv = new IvParameterSpec("12345678".getBytes());
AlgorithmParameterSpec paramSpec = iv;
cipher.init(Cipher.DECRYPT_MODE, secretKey, paramSpec);
return cipher.doFinal(data);
} catch (Exception e) {
throw new Exception(e);
}
}

/**
* DES算法，加密
* @param data 待加密字符串
* @param key 加密私钥，长度不能够小于8位
* @return 加密后的字节数组，一般结合Base64编码使用
* @throws CryptException 异常
*/
public static String encode(String key, String data) throws Exception {
return encode(key, data.getBytes());
}

/**
* DES算法，加密
* @param data 待加密字符串
* @param key 加密私钥，长度不能够小于8位
* @return 加密后的字节数组，一般结合Base64编码使用
* @throws CryptException
* 异常
*/
private static String encode(String key, byte[] data) throws Exception {
try {
DESKeySpec dks = new DESKeySpec(key.getBytes());
SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
// key的长度不能够小于8位字节
Key secretKey = keyFactory.generateSecret(dks);
Cipher cipher = Cipher.getInstance(ALGORITHM_DES);
IvParameterSpec iv = new IvParameterSpec("12345678".getBytes());
AlgorithmParameterSpec paramSpec = iv;
cipher.init(Cipher.ENCRYPT_MODE, secretKey, paramSpec);
byte[] bytes = cipher.doFinal(data);
return Base64.encodeToString(bytes, 0);
} catch (Exception e) {
throw new Exception(e);
}
}

}
本文地址：http://www.xszlo.com/article/2012-11-19/7501.html，转发请保留这个地址，谢谢

更多相关文章

随机推荐