C# 3DES加密详解
投稿：hebedich
3Des对每个数据块进行了三次的DES加密算法，是DES的一个更安全的变形。比起最初的DES，3DES更为安全。下面我们来看下在C#中的3DES加密方式的使用
最近一个项目中，因为服务端是用的java开发的，客户端是用的C#，由于通信部分采用到了3DES加密，所以做个记录，以备以后需要的时候直接用。
这是对方（java）的加密算法，和网上流传的代码也差不多（主密钥直接写死了，方便测试）
package org.zwork.market.mina.msg;
import java.security.spec.KeySpec;
import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;
import javax.crypto.spec.DESedeKeySpec;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.zwork.market.MktContants;
public class ThreeEncryptDecrypt {
private static final Logger LOGGER = LoggerFactory.getLogger(ThreeEncryptDecrypt.class);
// 定义 加密算法,可用 DES,DESede,Blowfish
public static final String Algorithm = "DESede";
public static String DES = "DES/ECB/NoPadding";
public static String TriDes = "DESede/ECB/NoPadding";
// des加密
public static byte[] des_crypt(byte key[], byte data[]) {
try {
KeySpec ks = new DESKeySpec(key);
SecretKeyFactory kf = SecretKeyFactory.getInstance("DES");
SecretKey ky = kf.generateSecret(ks);
Cipher c = Cipher.getInstance(DES);
c.init(Cipher.ENCRYPT_MODE, ky);
return c.doFinal(data);
} catch (Exception e) {
LOGGER.error("des_crypt error:", e);
return null;
}
}
// des解密
public static byte[] des_decrypt(byte key[], byte data[]) {
try {
KeySpec ks = new DESKeySpec(key);
SecretKeyFactory kf = SecretKeyFactory.getInstance("DES");
SecretKey ky = kf.generateSecret(ks);
Cipher c = Cipher.getInstance(DES);
c.init(Cipher.DECRYPT_MODE, ky);
return c.doFinal(data);
} catch (Exception e) {
LOGGER.error("des_decrypt error:", e);
return null;
}
}
// 3DES加密
public static byte[] trides_crypt(byte key[], byte data[]) {
try {
byte[] k = new byte[24];
int len = data.length;
if (data.length % 8 != 0) {
len = data.length - data.length % 8 + 8;
}
byte[] needData = null;
if (len != 0)
needData = new byte[len];
for (int i = 0; i < len; i++) {
needData[i] = 0x00;
}
System.arraycopy(data, 0, needData, 0, data.length);
if (key.length == 16) {
System.arraycopy(key, 0, k, 0, key.length);
System.arraycopy(key, 0, k, 16, 8);
} else {
System.arraycopy(key, 0, k, 0, 24);
}
KeySpec ks = new DESedeKeySpec(k);
SecretKeyFactory kf = SecretKeyFactory.getInstance("DESede");
SecretKey ky = kf.generateSecret(ks);
Cipher c = Cipher.getInstance(TriDes);
c.init(Cipher.ENCRYPT_MODE, ky);
return c.doFinal(needData);
} catch (Exception e) {
LOGGER.error("trides_crypt error:", e);
return null;
}
}
// 3DES解密
public static byte[] trides_decrypt(byte key[], byte data[]) {
try {
byte[] k = new byte[24];
int len = data.length;
if (data.length % 8 != 0) {
len = data.length - data.length % 8 + 8;
}
byte[] needData = null;
if (len != 0)
needData = new byte[len];
for (int i = 0; i < len; i++) {
needData[i] = 0x00;
}
System.arraycopy(data, 0, needData, 0, data.length);
if (key.length == 16) {
System.arraycopy(key, 0, k, 0, key.length);
System.arraycopy(key, 0, k, 16, 8);
} else {
System.arraycopy(key, 0, k, 0, 24);
}
KeySpec ks = new DESedeKeySpec(k);
SecretKeyFactory kf = SecretKeyFactory.getInstance("DESede");
SecretKey ky = kf.generateSecret(ks);
Cipher c = Cipher.getInstance(TriDes);
c.init(Cipher.DECRYPT_MODE, ky);
return c.doFinal(needData);
} catch (Exception e) {
LOGGER.error("trides_decrypt error:", e);
return null;
}
}
public static String getPass(String source) {
byte[] data= hexToBytes(source);
byte[] key ="111111111111111111111111111a1.1.".getBytes();
String result = byte2hex(trides_decrypt(key, data)).toUpperCase();
return result.substring(2, 8);
}
public static String byte2hex(byte[] data) {
StringBuffer sb = new StringBuffer();
for (int i = 0; i < data.length; i++) {
String temp = Integer.toHexString(((int) data[i]) & 0xFF);
for (int t = temp.length(); t < 2; t++) {
sb.append("0");
}
sb.append(temp);
}
return sb.toString();
}
public static byte[] hexToBytes(String str) {
if (str == null) {
return null;
} else if (str.length() < 2) {
return null;
} else {
int len = str.length() / 2;
byte[] buffer = new byte[len];
for (int i = 0; i < len; i++) {
buffer[i] = (byte) Integer.parseInt(str.substring(i * 2, i * 2 + 2), 16);
}
return buffer;
}
}
}
因为客户端只负责数据加密，所以我这里只写了加密的部分。由于java和C#语言很相似，所以我就仿这他们给的java代码改成C#的，当然也在网上参考了一些代码，不过中间还是出现了些问题，比如C#不支持弱密钥（把密钥弄复杂点）,因为没注意大小写造成加密结果不一致等等。编程这东西一个点都能让整个系统崩溃，所以小细节很重要！！！
public class DESHelper
{
/// <summary>
/// 将密码转成直接数组
/// </summary>
/// <param name="str"></param>
/// <returns></returns>
public static byte[] HexToBytes(String str)
{
if (str == null)
{
return null;
}
else if (str.Length < 2)
{
return null;
}
else
{
int len = str.Length / 2;
byte[] buffer = new byte[len];
for (int i = 0; i < len; i++)
{
var temp = str.Substring(i * 2, 2);
buffer[i] = (byte)Convert.ToInt32(temp, 16);
}
return buffer;
}
}
/// <summary>
/// 3DES加密
/// </summary>
/// <param name="key"></param>
/// <param name="data"></param>
/// <returns></returns>
public static byte[] GetDes3EncryptedText(byte[] key, byte[] data)
{
byte[] k = new byte[24];
int len = data.Length;
if (data.Length % 8 != 0)
{
len = data.Length - data.Length % 8 + 8;
}
byte[] needData = null;
if (len != 0)
needData = new byte[len];
for (int i = 0; i < len; i++)
{
needData[i] = 0x00;
}
Buffer.BlockCopy(data, 0, needData, 0, data.Length);
if (key.Length == 16)
{
Buffer.BlockCopy(key, 0, k, 0, key.Length);
Buffer.BlockCopy(key, 0, k, 16, 8);
}
else
{
Buffer.BlockCopy(key, 0, k, 0, 24);
}
var des3 = new TripleDESCryptoServiceProvider();
des3.Key = k;
des3.Mode = CipherMode.ECB;
des3.Padding = PaddingMode.Zeros;
using (MemoryStream ms = new MemoryStream())
using (CryptoStream cs = new CryptoStream(ms, des3.CreateEncryptor(), CryptoStreamMode.Write))
{
cs.Write(data, 0, data.Length);
cs.FlushFinalBlock();
return ms.ToArray();
}
}
/// <summary>
/// 将加密结果转成字符串
/// </summary>
/// <param name="data"></param>
/// <returns></returns>
public static String GetByte2Hex(byte[] data)
{
StringBuilder sb = new StringBuilder();
for (int i = 0; i < data.Length; i++)
{
String temp = string.Format("{0:X}", ((int)data[i]) & 0xFF);
for (int t = temp.Length; t < 2; t++)
{
sb.Append("0");
}
sb.Append(temp);
}
return sb.ToString();
}
}
以上所述就是本文的全部内容了，希望大家能够喜欢。