强签名大家并不陌生,如下图所示:
  
 
 如果代码是机密的,还需要用到 仅延迟签名,  
 
如果只这样做了,代码中没什么逻辑判断,代码还是不够安全的:
1. Strong Name Remover 工具可以很容易的清除你的签名,如下图:
  
 
2. 签名替换工具,如下图:
  
 
所以,仅仅有签名是不够的,还需要在代码中判断程序集中是否有签名,且签名是自己的。
接下来,需要做的工作如下:
1. public key token
在 Visual Studio Tools 中找到命令提示,启动并执行 ”sn -Tp 你的程序集“
  
 
2. 代码
  const string _sLicenseErr = "FCL.Core 被篡改...";          [DllImport("mscoree.dll", CharSet = CharSet.Unicode)]         public static extern bool StrongNameSignatureVerificationEx(string wszFilePath,                                                                      bool fForceVerification,                                                                      ref bool pfWasVerified);                 string wszFilePath = Assembly.GetExecutingAssembly().Location;                          Debug.WriteLine(wszFilePath);             bool fForceVerification = true;             bool pfWasVerified = false;              bool bFlg = StrongNameSignatureVerificationEx(wszFilePath, fForceVerification, ref pfWasVerified);             if (!bFlg)             {                 throw new Exception(_sLicenseErr + " 0x0001");             }              byte[] data = Assembly.GetExecutingAssembly().GetName().GetPublicKeyToken();             if (data.Length == 0)             {                 throw new Exception(_sLicenseErr + " 0x0002");             }             StringBuilder sb = new StringBuilder();             foreach (byte b in data)             {                 sb.AppendFormat("{0:x2}", b);             }             string sPK = sb.ToString();             if (sPK != "???f8f1c????ffdf")             {                 throw new Exception(_sLicenseErr + " 0x0003");             }