AES
高级加密标准（英语：Advanced Encryption Standard，缩写：AES），在密码学中又称Rijndael加密法，是美国联邦政府采用的一种区块加密标准。这个标准用来替代原先的DES，已经被多方分析且广为全世界所使用。AES先进加密算法是一向被认为牢不可破的加密算法，针对这项加密算法的攻击是异常复杂的，事实上想要完全破解AES花费的时间要以数十亿年计，极大的保证了数据的安全性。
这里有两个加密、解密方法： 一种是带密钥的加密；一种是动态加密，就是不需要密钥，密钥被动态生成并且保存在密文中，解密时先解密密钥，在解密密文。
using System; using System.Security.Cryptography; using System.Text; namespace Common.CryptHelper { public class AESCrypt { public const string RET_ERROR = "x07x07x07x07x07"; private byte[] _IV = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF, 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF }; private byte[] _Key = { 0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5, 0x30, 0x01, 0x67, 0x2b, 0xfe, 0xd7, 0xab, 0x76, 0xca, 0x82, 0xc9, 0x7d, 0xfa, 0x59, 0x47, 0xf0, 0xad, 0xd4, 0xa2, 0xaf, 0x9c, 0xa4, 0x72, 0xc0, 0xb7, 0xfd, 0x93, 0x26, 0x36, 0x3f, 0xf7, 0xcc, 0x34, 0xa5, 0xe5, 0xf1, 0x71, 0xd8, 0x31, 0x15, 0x04, 0xc7, 0x23, 0xc3, 0x18, 0x96, 0x05, 0x9a, 0x07, 0x12, 0x80, 0xe2, 0xeb, 0x27, 0xb2, 0x75, 0x09, 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0, 0x52, 0x3b, 0xd6, 0xb3, 0x29, 0xe3, 0x2f, 0x84, 0x53, 0xd1, 0x00, 0xed, 0x20, 0xfc, 0xb1, 0x5b, 0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf, 0xd0, 0xef, 0xaa, 0xfb, 0x43, 0x4d, 0x33, 0x85, 0x45, 0xf9, 0x02, 0x7f, 0x50, 0x3c, 0x9f, 0xa8, 0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5, 0xbc, 0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2, 0xcd, 0x0c, 0x13, 0xec, 0x5f, 0x97, 0x44, 0x17, 0xc4, 0xa7, 0x7e, 0x3d, 0x64, 0x5d, 0x19, 0x73, 0x60, 0x81, 0x4f, 0xdc, 0x22, 0x2a, 0x90, 0x88, 0x46, 0xee, 0xb8, 0x14, 0xde, 0x5e, 0x0b, 0xdb, 0xe0, 0x32, 0x3a, 0x0a, 0x49, 0x06, 0x24, 0x5c, 0xc2, 0xd3, 0xac, 0x62, 0x91, 0x95, 0xe4, 0x79, 0xe7, 0xc8, 0x37, 0x6d, 0x8d, 0xd5, 0x4e, 0xa9, 0x6c, 0x56, 0xf4, 0xea, 0x65, 0x7a, 0xae, 0x08, 0xba, 0x78, 0x25, 0x2e, 0x1c, 0xa6, 0xb4, 0xc6, 0xe8, 0xdd, 0x74, 0x1f, 0x4b, 0xbd, 0x8b, 0x8a, 0x70, 0x3e, 0xb5, 0x66, 0x48, 0x03, 0xf6, 0x0e, 0x61, 0x35, 0x57, 0xb9, 0x86, 0xc1, 0x1d, 0x9e, 0xe1, 0xf8, 0x98, 0x11, 0x69, 0xd9, 0x8e, 0x94, 0x9b, 0x1e, 0x87, 0xe9, 0xce, 0x55, 0x28, 0xdf, 0x8c, 0xa1, 0x89, 0x0d, 0xbf, 0xe6, 0x42, 0x68, 0x41, 0x99, 0x2d, 0x0f, 0xb0, 0x54, 0xbb, 0x16 }; private const string CRYPTO_KEY = "ADVANCEDENCRYPTIONSTANDARD"; private int CRYPTO_KEY_LENGTH = 32; private AesCryptoServiceProvider m_aesCryptoServiceProvider; private string m_message; public string Message { get { return m_message; } set { m_message = value; } } private bool m_containKey; /// <summary> /// True：密文中包含密钥 /// False：密文中不包含密钥 /// </summary> public bool ContainKey { get { return m_containKey; } set { m_containKey = value; } } public AESCrypt() { m_aesCryptoServiceProvider = new AesCryptoServiceProvider(); m_containKey = true; m_message = string.Empty; } public AESCrypt(bool containKey) : this() { m_containKey = containKey; } private string Encrypt(string s_crypto, byte[] key) { string s_encryped = string.Empty; byte[] crypto, encrypted; ICryptoTransform ct; try { crypto = string2Byte(s_crypto); m_aesCryptoServiceProvider.Key = key; m_aesCryptoServiceProvider.IV = _IV; ct = m_aesCryptoServiceProvider.CreateEncryptor(); encrypted = ct.TransformFinalBlock(crypto, 0, crypto.Length); if (m_containKey) { s_encryped += byte2HexString(key); } s_encryped += byte2HexString(encrypted); return s_encryped; } catch (Exception ex) { m_message = ex.ToString(); return RET_ERROR; } } private string Decrypt(string s_encrypted, byte[] key) { string s_decrypted = string.Empty; byte[] encrypted, decrypted; ICryptoTransform ct; try { encrypted = hexString2Byte(s_encrypted); m_aesCryptoServiceProvider.Key = key; m_aesCryptoServiceProvider.IV = _IV; ct = m_aesCryptoServiceProvider.CreateDecryptor(); decrypted = ct.TransformFinalBlock(encrypted, 0, encrypted.Length); s_decrypted += byte2String(decrypted); return s_decrypted; } catch (Exception ex) { m_message = ex.ToString(); m_message = "Decrypt fail."; return RET_ERROR; } } #region 指定密钥对明文进行AES加密、解密 /// <summary> /// 指定密钥对明文进行AES加密 /// </summary> /// <param name="s_crypto">明文</param> /// <param name="s_key">加密密钥</param> /// <returns></returns> public string Encrypt(string s_crypto, string s_key) { byte[] key = new byte[CRYPTO_KEY_LENGTH]; byte[] temp = string2Byte(s_key); if (temp.Length > key.Length) { m_message = "Key too long,need less than 32 Bytes key."; return RET_ERROR; } key = string2Byte(s_key.PadRight(key.Length)); return Encrypt(s_crypto, key); } /// <summary> /// 指定密钥，并对密文进行解密 /// </summary> /// <param name="s_encrypted">密文</param> /// <param name="s_key">密钥</param> /// <returns></returns> public string Decrypt(string s_encrypted, string s_key) { byte[] key = new byte[CRYPTO_KEY_LENGTH]; byte[] temp = string2Byte(s_key); if (temp.Length > key.Length) { m_message = "Key invalid.too long,need less than 32 Bytes"; return RET_ERROR; } key = string2Byte(s_key.PadRight(key.Length)); if (m_containKey) { s_encrypted = s_encrypted.Substring(CRYPTO_KEY_LENGTH * 2); } return Decrypt(s_encrypted, key); } #endregion #region 动态生成密钥，并对明文进行AES加密、解密 /// <summary> /// 动态生成密钥，并对明文进行AES加密 /// </summary> /// <param name="s_crypto">明文</param> /// <returns></returns> public string Encrypt(string s_crypto) { byte[] key = new byte[CRYPTO_KEY_LENGTH]; m_aesCryptoServiceProvider.GenerateKey(); key = m_aesCryptoServiceProvider.Key; return Encrypt(s_crypto, key); } /// <summary> /// 从密文中解析出密钥，并对密文进行解密 /// </summary> /// <param name="s_encrypted">密文</param> /// <returns></returns> public string Decrypt(string s_encrypted) { string s_key = string.Empty; byte[] key = new byte[CRYPTO_KEY_LENGTH]; if (s_encrypted.Length <= CRYPTO_KEY_LENGTH * 2) { m_message = "Encrypted string invalid."; return RET_ERROR; } if (m_containKey) { s_key = s_encrypted.Substring(0, CRYPTO_KEY_LENGTH * 2); s_encrypted = s_encrypted.Substring(CRYPTO_KEY_LENGTH * 2); } key = hexString2Byte(s_key); return Decrypt(s_encrypted, key); } #endregion #region 私有方法 private string byte2HexString(byte[] bytes) { StringBuilder sb = new StringBuilder(); foreach (byte b in bytes) { sb.AppendFormat("{0:X2}", b); } return sb.ToString(); } private byte[] hexString2Byte(string hex) { int len = hex.Length / 2; byte[] bytes = new byte[len]; for (int i = 0; i < len; i++) { bytes[i] = (byte)(Convert.ToInt32(hex.Substring(i * 2, 2), 16)); } return bytes; } private byte[] string2Byte(string str) { return Encoding.UTF8.GetBytes(str); } private string byte2String(byte[] bytes) { return Encoding.UTF8.GetString(bytes); } #endregion } }