public static class EncryptAndDecrypt
{
//加密
public static string Encrypt(string input)
{
// 盐值
string saltValue = "saltValue";
// 密码值
string pwdValue = "pwdValue";
byte[] data = System.Text.UTF8Encoding.UTF8.GetBytes(input);
byte[] salt = System.Text.UTF8Encoding.UTF8.GetBytes(saltValue);
// AesManaged - 高级加密标准(AES) 对称算法的管理类
System.Security.Cryptography.AesManaged aes = new System.Security.Cryptography.AesManaged();
// Rfc2898DeriveBytes - 通过使用基于 HMACSHA1 的伪随机数生成器，实现基于密码的密钥派生功能 (PBKDF2 - 一种基于密码的密钥派生函数)
// 通过 密码 和 salt 派生密钥
System.Security.Cryptography.Rfc2898DeriveBytes rfc = new System.Security.Cryptography.Rfc2898DeriveBytes(pwdValue, salt);
/**/
/*
* AesManaged.BlockSize - 加密操作的块大小（单位：bit）
* AesManaged.LegalBlockSizes - 对称算法支持的块大小（单位：bit）
* AesManaged.KeySize - 对称算法的密钥大小（单位：bit）
* AesManaged.LegalKeySizes - 对称算法支持的密钥大小（单位：bit）
* AesManaged.Key - 对称算法的密钥
* AesManaged.IV - 对称算法的密钥大小
* Rfc2898DeriveBytes.GetBytes(int 需要生成的伪随机密钥字节数) - 生成密钥
*/
aes.BlockSize = aes.LegalBlockSizes[0].MaxSize;
aes.KeySize = aes.LegalKeySizes[0].MaxSize;
aes.Key = rfc.GetBytes(aes.KeySize / 8);
aes.IV = rfc.GetBytes(aes.BlockSize / 8);
// 用当前的 Key 属性和初始化向量 IV 创建对称加密器对象
System.Security.Cryptography.ICryptoTransform encryptTransform = aes.CreateEncryptor();
// 加密后的输出流
System.IO.MemoryStream encryptStream = new System.IO.MemoryStream();
// 将加密后的目标流（encryptStream）与加密转换（encryptTransform）相连接
System.Security.Cryptography.CryptoStream encryptor = new System.Security.Cryptography.CryptoStream
(encryptStream, encryptTransform, System.Security.Cryptography.CryptoStreamMode.Write);
// 将一个字节序列写入当前 CryptoStream （完成加密的过程）
encryptor.Write(data, 0, data.Length);
encryptor.Close();
// 将加密后所得到的流转换成字节数组，再用Base64编码将其转换为字符串
string encryptedString = Convert.ToBase64String(encryptStream.ToArray());
return encryptedString;
}
#region silverlight密码解密
/**/
/// <summary>
/// 解密数据
/// </summary>
/// <param name="input">加密后的字符串</param>
/// <returns>加密前的字符串</returns>
public static string Decrypt(string input)
{
// 盐值（与加密时设置的值一致）
string saltValue = "saltValue";
// 密码值（与加密时设置的值一致）
string pwdValue = "pwdValue";
byte[] encryptBytes = Convert.FromBase64String(input);
byte[] salt = Encoding.UTF8.GetBytes(saltValue);
System.Security.Cryptography.AesManaged aes = new System.Security.Cryptography.AesManaged();
System.Security.Cryptography.Rfc2898DeriveBytes rfc = new System.Security.Cryptography.Rfc2898DeriveBytes(pwdValue, salt);
aes.BlockSize = aes.LegalBlockSizes[0].MaxSize;
aes.KeySize = aes.LegalKeySizes[0].MaxSize;
aes.Key = rfc.GetBytes(aes.KeySize / 8);
aes.IV = rfc.GetBytes(aes.BlockSize / 8);
// 用当前的 Key 属性和初始化向量 IV 创建对称解密器对象
System.Security.Cryptography.ICryptoTransform decryptTransform = aes.CreateDecryptor();
// 解密后的输出流
MemoryStream decryptStream = new MemoryStream();
// 将解密后的目标流（decryptStream）与解密转换（decryptTransform）相连接
System.Security.Cryptography.CryptoStream decryptor = new System.Security.Cryptography.CryptoStream(
decryptStream, decryptTransform, System.Security.Cryptography.CryptoStreamMode.Write);
// 将一个字节序列写入当前 CryptoStream （完成解密的过程）
decryptor.Write(encryptBytes, 0, encryptBytes.Length);
decryptor.Close();
// 将解密后所得到的流转换为字符串
byte[] decryptBytes = decryptStream.ToArray();
string decryptedString = UTF8Encoding.UTF8.GetString(decryptBytes, 0, decryptBytes.Length);
return decryptedString;
}
#endregion
}
