虽然我在某种程度上同意 Teoman Soygul 关于 CRC/Hash 的帖子，但有一件非常重要的事情需要注意。永远不要加密散列，因为这样可以更容易找到生成的密钥。即使不加密哈希，您仍然可以为他们提供一种简单的方法来测试他们是否成功获得了正确的密码；但是，让我们假设这已经是可能的。因为我知道你加密了什么样的数据，无论是文本，还是序列化的对象，或者其他什么，我很可能可以编写代码来识别它。
也就是说，我使用以下代码的派生来加密/解密数据：
static void Main()
{
byte[] test = Encrypt(Encoding.UTF8.GetBytes("Hello World!"), "My Product Name and/or whatever constant", "password");
Console.WriteLine(Convert.ToBase64String(test));
string plain = Encoding.UTF8.GetString(Decrypt(test, "My Product Name and/or whatever constant", "passwords"));
Console.WriteLine(plain);
}
public static byte[] Encrypt(byte[] data, string iv, string password)
{
using (RijndaelManaged m = new RijndaelManaged())
using (SHA256Managed h = new SHA256Managed())
{
m.KeySize = 256;
m.BlockSize = 256;
byte[] hash = h.ComputeHash(data);
byte[] salt = new byte[32];
new RNGCryptoServiceProvider().GetBytes(salt);
m.IV = h.ComputeHash(Encoding.UTF8.GetBytes(iv));
m.Key = new Rfc2898DeriveBytes(password, salt) { IterationCount = 10000 }.GetBytes(32);
using (MemoryStream ms = new MemoryStream())
{
ms.Write(hash, 0, hash.Length);
ms.Write(salt, 0, salt.Length);
using (CryptoStream cs = new CryptoStream(ms, m.CreateEncryptor(), CryptoStreamMode.Write))
{
cs.Write(data, 0, data.Length);
cs.FlushFinalBlock();
return ms.ToArray();
}
}
}
}
public static byte[] Decrypt(byte[] data, string iv, string password)
{
using (MemoryStream ms = new MemoryStream(data, false))
using (RijndaelManaged m = new RijndaelManaged())
using (SHA256Managed h = new SHA256Managed())
{
try
{
m.KeySize = 256;
m.BlockSize = 256;
byte[] hash = new byte[32];
ms.Read(hash, 0, 32);
byte[] salt = new byte[32];
ms.Read(salt, 0, 32);
m.IV = h.ComputeHash(Encoding.UTF8.GetBytes(iv));
m.Key = new Rfc2898DeriveBytes(password, salt) { IterationCount = 10000 }.GetBytes(32);
using (MemoryStream result = new MemoryStream())
{
using (CryptoStream cs = new CryptoStream(ms, m.CreateDecryptor(), CryptoStreamMode.Read))
{
byte[] buffer = new byte[1024];
int len;
while ((len = cs.Read(buffer, 0, buffer.Length)) > 0)
result.Write(buffer, 0, len);
}
byte[] final = result.ToArray();
if (Convert.ToBase64String(hash) != Convert.ToBase64String(h.ComputeHash(final)))
throw new UnauthorizedAccessException();
return final;
}
}
catch
{
//never leak the exception type...
throw new UnauthorizedAccessException();
}
}
}