加密算法

一、3DES加密算法3DES（或称为Triple DES）是三重数据加密算法（TDEA，Triple Data Encryption Algorithm）块密码的通称。

它相当于是对每个数据块应用三次DES加密算法。

由于计算机运算能力的增强，原版DES密码的密钥长度变得容易被暴力破解；3DES即是设计用来提供一种相对简单的方法，即通过增加DES的密钥长度来避免类似的攻击，而不是设计一种全新的块密码算法。

1、Java代码示例import javax.crypto.Cipher;import javax.crypto.spec.SecretKeySpec;import mons.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_ALG ORITHM);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_ALG ORITHM);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 byteprivate static Byte[] EncryptionIV = Encoding.Default.GetBytes(" ");/// <summary>/// Constructor/// </summary>public CryptionData(){}/// <summary>/// Constructor/// </summary>/// <param name="EncryptionString">SecureKey</param>public CryptionData(string EncryptionString){this.EncryptionString = EncryptionString;}/// <summary>/// Encryption method for byte array/// </summary>/// <param name="SourceData">source data</param>/// <returns>byte array</returns>public byte[] EncryptionByteData(byte[] SourceData){byte[] returnData = null;try{// Create TripleDESCryptoServiceProvider objectTripleDESCryptoServiceProvider desProvider = new TripleDESCryptoServiceProvide r();// Set SecureKey and IV of desProviderbyte[] byteKey = Encoding.Default.GetBytes(EncryptionString);desProvider.Key = byteKey;desProvider.IV = EncryptionIV;desProvider.Mode = CipherMode.ECB;// A MemoryStream objectMemoryStream ms = new MemoryStream();// Create EncryptorICryptoTransform encrypto = desProvider.CreateEncryptor();// Create CryptoStream objectCryptoStream cs = new CryptoStream(ms, encrypto, CryptoStreamMode.Write);// Encrypt SourceDatacs.Write(SourceData, 0, SourceData.Length);cs.FlushFinalBlock();// Get Encryption resultreturnData = ms.ToArray();}catch (Exception ex){throw ex;}return returnData;}/// <summary>/// Decryption method for byte array/// </summary>/// <param name="SourceData">source data</param>/// <returns>byte array</returns>public byte[] DecryptionByteData(byte[] SourceData){byte[] returnData = null;try{// Create TripleDESCryptoServiceProvider objectTripleDESCryptoServiceProvider desProvider = new TripleDESCryptoServiceProvide r();// Set SecureKey and IV of desProviderbyte[] byteKey = Encoding.Default.GetBytes(EncryptionString);desProvider.Key = byteKey;desProvider.IV = EncryptionIV;desProvider.Mode = CipherMode.ECB;// A MemoryStream objectMemoryStream ms = new MemoryStream();// Create DecryptorICryptoTransform encrypto = desProvider.CreateDecryptor();// Create CryptoStream objectCryptoStream cs = new CryptoStream(ms, encrypto, CryptoStreamMode.Write);// Decrypt SourceDatacs.Write(SourceData, 0, SourceData.Length);cs.FlushFinalBlock();// Get Decryption resultreturnData = ms.ToArray();}catch (Exception ex){throw ex;}return returnData;}/// <summary>/// Encryption method for string/// </summary>/// <param name="SourceData">source data</param>/// <returns>string</returns>public string EncryptionStringData(string SourceData){try{// Convert source data from string to byte arraybyte[] SourData = Encoding.Default.GetBytes(SourceData);// Encrypt byte arraybyte[] retData = EncryptionByteData(SourData);// Convert encryption result from byte array to Base64Stringreturn Convert.ToBase64String(retData, 0, retData.Length); }catch (Exception ex){throw ex;}}/// <summary>/// Decryption method for string/// </summary>/// <param name="SourceData">source data</param>/// <returns>string</returns>public string DecryptionStringdata(string SourceData){try{// Convert source data from Base64String to byte arraybyte[] SourData = Convert.FromBase64String(SourceData);// Decrypt byte arraybyte[] retData = DecryptionByteData(SourData);// Convert Decryption result from byte array to stringreturn Encoding.Default.GetString(retData, 0, retData.Length); }catch (Exception ex){throw ex;}}}二、AES加密AES 是一个新的可以用于保护电子数据的加密算法。