莉恩 ugirls尤果网:3DES

3DES加密算法 在 weblogic中创建数据源的时候，要用到数据库口令，其中数据库口令是加密的，表述为：PasswordEncrypted={3DES}，在配置的时候，可将PasswordEncrypted改为Password，然后写明文，在下次app server启动时会将该明文加密，如下：
Clear text values are found in config.xml file. These values will be replaced with encrypted values upon boot but these values may have been copied to config.xml.original file. In Development Mode, these values will remain unencrypted until next server reboot. In Production mode, user will be prompted for action.
3DES加密算法介绍：
3DES是DES加密算法的一种模式，它使用3条64位的密钥对数据进行三次加密。数据加密标准（DES）是美国的一种由来已久的加密标准，它使用对称密钥加密法，并于1981年被ANSI组织规范为ANSI X.3.92。DES使用56位密钥和密码块的方法，而在密码块的方法中，文本被分成64位大小的文本块然后再进行加密。比起最初的DES，3DES更为安全。
3DES（即Triple DES）是DES向AES过渡的加密算法（1999年，NIST将3-DES指定为过渡的加密标准），是DES的一个更安全的变形。它以DES为基本模块，通过组合分组方法设计出分组加密算法，其具体实现如下：设Ek()和Dk()代表DES算法的加密和解密过程，K代表DES算法使用的密钥，P代表明文，C代表密表，这样，
3DES加密过程为：C=Ek3(Dk2(Ek1(P)))
3DES解密过程为：P=Dk1((EK2(Dk3(C)))
具体的加/解密过程如图所示。
using System;
using System.Text;
using System.IO;
using System.Security.Cryptography;
class Class1
{
static void Main()
{
Console.WriteLine("Encrypt String...");
txtKey = "tkGGRmBErvc=";
btnKeyGen();
Console.WriteLine("Encrypt Key :",txtKey);
txtIV = "Kl7ZgtM1dvQ=";
btnIVGen();
Console.WriteLine("Encrypt IV :",txtIV);
Console.WriteLine();
string txtEncrypted = EncryptString("1111");
Console.WriteLine("Encrypt String : ",txtEncrypted);
string txtOriginal = DecryptString(txtEncrypted);
Console.WriteLine("Decrypt String : ",txtOriginal);
}
private static SymmetricAlgorithm mCSP;
private static string txtKey;
private static string txtIV;
private static void btnKeyGen()
{
mCSP = SetEnc();
byte[] byt2 = Convert.FromBase64String(txtKey);
mCSP.Key = byt2;
}
private static void btnIVGen()
{
byte[] byt2 = Convert.FromBase64String(txtIV);
mCSP.IV = byt2;
}
private static string EncryptString(string Value)
{
ICryptoTransform ct;
MemoryStream ms;
CryptoStream cs;
byte[] byt;
ct = mCSP.CreateEncryptor(mCSP.Key, mCSP.IV);
byt = Encoding.UTF8.GetBytes(Value);
ms = new MemoryStream();
cs = new CryptoStream(ms, ct, CryptoStreamMode.Write);
cs.Write(byt, 0, byt.Length);
cs.FlushFinalBlock();
cs.Close();
return Convert.ToBase64String(ms.ToArray());
}
private static string DecryptString(string Value)
{
ICryptoTransform ct;
MemoryStream ms;
CryptoStream cs;
byte[] byt;
ct = mCSP.CreateDecryptor(mCSP.Key, mCSP.IV);
byt = Convert.FromBase64String(Value);
ms = new MemoryStream();
cs = new CryptoStream(ms, ct, CryptoStreamMode.Write);
cs.Write(byt, 0, byt.Length);
cs.FlushFinalBlock();
cs.Close();
return Encoding.UTF8.GetString(ms.ToArray());
}
private static SymmetricAlgorithm SetEnc()
{
return new DESCryptoServiceProvider();
}
}
K1、K2、K3决定了算法的安全性，若三个密钥互不相同，本质上就相当于用一个长为168位的密钥进行加密。多年来，它在对付强力攻击时是比较安全的。若数据对安全性要求不那么高，K1可以等于K3。在这种情况下，密钥的有效长度为112位。
3DES算法实现
java中的Cipher.DECRYPR_MODE
import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;

import org.apache.commons.codec.binary.Base64;

public class CryptUtil3DES {
    private static final String CRYPT_KEY = "v3VC7LfCq6IL5KgIglqZrQ1b";
    private static final String CRYPT_ALGORITHM = "DESede";

    public static String decrypt(String value) {
        try {
            SecretKeySpec keySpec = new SecretKeySpec(CRYPT_KEY.getBytes(), CRYPT_ALGORITHM);
            Cipher cipher = Cipher.getInstance(CRYPT_ALGORITHM);
            cipher.init(Cipher.DECRYPT_MODE, keySpec);

            byte[] decodedByte = Base64.decodeBase64(value.getBytes());
            byte[] decryptedByte = cipher.doFinal(decodedByte);
            return new String(decryptedByte);
        } catch(Exception e) {
            return null;
        }
    }

    public static String encrypt(String value) {
        try {
            SecretKeySpec keySpec = new SecretKeySpec(CRYPT_KEY.getBytes(), CRYPT_ALGORITHM);
            Cipher cipher = Cipher.getInstance(CRYPT_ALGORITHM);
            cipher.init(Cipher.ENCRYPT_MODE, keySpec);

            byte[] encryptedByte = cipher.doFinal(value.getBytes());
            byte[] encodedByte = Base64.encodeBase64(encryptedByte);
            return new String(encodedByte);
        } catch(Exception e) {
            return null;
        }
    }
}

2。C#
public class CryptionData
{
    // The length of Encryptionstring should be 24 byte and not be a weak key
    private string EncryptionString;

    // The length of initialization vector should be 8 byte
    private static Byte[] EncryptionIV = Encoding.Default.GetBytes("        ");

    /// 

    /// Constructor
    /// 

    public CryptionData()
    {

    }

    /// 

    /// Constructor
    /// 

    /// SecureKey
    public CryptionData(string EncryptionString)
    {
        this.EncryptionString = EncryptionString;
    }

    /// 

    /// Encryption method for byte array
    /// 

    /// source data
    /// byte array
    public byte[] EncryptionByteData(byte[] SourceData)
    {
        byte[] returnData = null;
        try
        {
            // Create TripleDESCryptoServiceProvider object
            TripleDESCryptoServiceProvider desProvider = new TripleDESCryptoServiceProvider();

            // Set SecureKey and IV of desProvider
            byte[] byteKey = Encoding.Default.GetBytes(EncryptionString);
            desProvider.Key = byteKey;
            desProvider.IV = EncryptionIV;
            desProvider.Mode = CipherMode.ECB;

            // A MemoryStream object
            MemoryStream ms = new MemoryStream();

            // Create Encryptor
            ICryptoTransform encrypto = desProvider.CreateEncryptor();

            // Create CryptoStream object
            CryptoStream cs = new CryptoStream(ms, encrypto, CryptoStreamMode.Write);

            // Encrypt SourceData
            cs.Write(SourceData, 0, SourceData.Length);
            cs.FlushFinalBlock();

            // Get Encryption result
            returnData = ms.ToArray();
        }
        catch (Exception ex)
        {
            throw ex;
        }

        return returnData;

    }

    /// 

    /// Decryption method for byte array
    /// 

    /// source data
    /// byte array
    public byte[] DecryptionByteData(byte[] SourceData)
    {
        byte[] returnData = null;
        try
        {
            // Create TripleDESCryptoServiceProvider object
            TripleDESCryptoServiceProvider desProvider = new TripleDESCryptoServiceProvider();

            // Set SecureKey and IV of desProvider
            byte[] byteKey = Encoding.Default.GetBytes(EncryptionString);
            desProvider.Key = byteKey;
            desProvider.IV = EncryptionIV;
            desProvider.Mode = CipherMode.ECB;
            // A MemoryStream object
            MemoryStream ms = new MemoryStream();

            // Create Decryptor
            ICryptoTransform encrypto = desProvider.CreateDecryptor();

            // Create CryptoStream object
            CryptoStream cs = new CryptoStream(ms, encrypto, CryptoStreamMode.Write);

            // Decrypt SourceData
            cs.Write(SourceData, 0, SourceData.Length);
            cs.FlushFinalBlock();

            // Get Decryption result
            returnData = ms.ToArray();
        }
        catch (Exception ex)
        {
            throw ex;
        }
        return returnData;

    }

    /// 

    /// Encryption method for string
    /// 

    /// source data
    /// string
    public string EncryptionStringData(string SourceData)
    {
        try
        {
            // Convert source data from string to byte array
            byte[] SourData = Encoding.Default.GetBytes(SourceData);

            // Encrypt byte array
            byte[] retData = EncryptionByteData(SourData);

            // Convert encryption result from byte array to Base64String
            return Convert.ToBase64String(retData, 0, retData.Length);
        }
        catch (Exception ex)
        {
            throw ex;
        }
    }

    /// 

    /// Decryption method for string
    /// 

    /// source data
    /// string
    public string DecryptionStringdata(string SourceData)
    {
        try
        {
            // Convert source data from Base64String to byte array
            byte[] SourData = Convert.FromBase64String(SourceData);

            // Decrypt byte array
            byte[] retData = DecryptionByteData(SourData);

            // Convert Decryption result from byte array to string
            return Encoding.Default.GetString(retData, 0, retData.Length);
        }
        catch (Exception ex)
        {
            throw ex;
        }
    }
}