如何判断两个 .NET DLL 是否相同? [英] How can I tell whether two .NET DLLs are the same?
问题描述
我有一个 DLL 的源代码，而且我有一个它的编译版本在某处.
I have the source for a DLL and I have a compiled version of it lying around somewhere.
如果我编译源代码，它将与已经编译的版本有不同的日期.
If I compile the source it will have a different date to the already-compiled version.
如何判断它们实际上是否相同，只是编译时间不同?
How can I tell whether they are in fact the same and have merely been compiled at different times?
推荐答案
要比较两个 .dll 文件，您可以使用 ildasm 或任何其他工具来获取 IL 代码.我在 dll 文件中创建了一个嵌入 ildasm 的示例，以便您可以在每台机器上使用它.当我们反汇编一个程序集时，我们检查执行程序集文件夹中是否存在 ildasm.exe 文件，如果不存在，则从我们的 dll 文件中提取该文件.使用 ildasm 文件，我们获取 IL 代码并将其保存到一个临时文件中.然后我们需要删除以下三行:
To compare two .dll files you can use ildasm or any other tool for geting IL code. I have created a sample with embedded ildasm in the dll file so that you can use it on every machine. When we disassemble an assembly we check if the ildasm.exe file exists in the executing assembly folder and if not the file is extracted there from our dll file. Using the ildasm file we get the IL code and save it to a temporary file. Then we need to remove the following three rows:
MVID - 正如我之前写的，这是每次构建时生成的唯一 GUID
图像库(图像库告诉我们程序将被 Windows 加载器加载到内存中的哪个位置.) - 这对于每个构建也是不同的
时间-日期戳 - ildasm 运行的时间和日期
所以我们读取临时文件内容，使用正则表达式删除这些行，然后将文件内容保存到同一个文件中.这是反汇编程序类:
So we read the temp file content, remove these rows using the regexes, and then save the file content to the same file. Here is the Disassembler class:
using System;
using System.IO;
using System.Linq;
using System.Reflection;
using System.Diagnostics;
using System.Text.RegularExpressions;
namespace FileHasher
{
public class Disassembler
{
public static Regex regexMVID = new Regex("//\s*MVID\:\s*\{[a-zA-Z0-9\-]+\}", RegexOptions.Multiline | RegexOptions.Compiled);
public static Regex regexImageBase = new Regex("//\s*Image\s+base\:\s0x[0-9A-Fa-f]*", RegexOptions.Multiline | RegexOptions.Compiled);
public static Regex regexTimeStamp = new Regex("//\s*Time-date\s+stamp\:\s*0x[0-9A-Fa-f]*", RegexOptions.Multiline | RegexOptions.Compiled);
private static readonly Lazy<Assembly> currentAssembly = new Lazy<Assembly>(() =>
{
return MethodBase.GetCurrentMethod().DeclaringType.Assembly;
});
private static readonly Lazy<string> executingAssemblyPath = new Lazy<string>(() =>
{
return Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location);
});
private static readonly Lazy<string> currentAssemblyFolder = new Lazy<string>(() =>
{
return Path.GetDirectoryName(currentAssembly.Value.Location);
});
private static readonly Lazy<string[]> arrResources = new Lazy<string[]>(() =>
{
return currentAssembly.Value.GetManifestResourceNames();
});
private const string ildasmArguments = "/all /text "{0}"";
public static string ILDasmFileLocation
{
get
{
return Path.Combine(executingAssemblyPath.Value, "ildasm.exe");
}
}
static Disassembler()
{
//extract the ildasm file to the executing assembly location
ExtractFileToLocation("ildasm.exe", ILDasmFileLocation);
}
/// <summary>
/// Saves the file from embedded resource to a given location.
/// </summary>
/// <param name="embeddedResourceName">Name of the embedded resource.</param>
/// <param name="fileName">Name of the file.</param>
protected static void SaveFileFromEmbeddedResource(string embeddedResourceName, string fileName)
{
if (File.Exists(fileName))
{
//the file already exists, we can add deletion here if we want to change the version of the 7zip
return;
}
FileInfo fileInfoOutputFile = new FileInfo(fileName);
using (FileStream streamToOutputFile = fileInfoOutputFile.OpenWrite())
using (Stream streamToResourceFile = currentAssembly.Value.GetManifestResourceStream(embeddedResourceName))
{
const int size = 4096;
byte[] bytes = new byte[4096];
int numBytes;
while ((numBytes = streamToResourceFile.Read(bytes, 0, size)) > 0)
{
streamToOutputFile.Write(bytes, 0, numBytes);
}
streamToOutputFile.Close();
streamToResourceFile.Close();
}
}
/// <summary>
/// Searches the embedded resource and extracts it to the given location.
/// </summary>
/// <param name="fileNameInDll">The file name in DLL.</param>
/// <param name="outFileName">Name of the out file.</param>
protected static void ExtractFileToLocation(string fileNameInDll, string outFileName)
{
string resourcePath = arrResources.Value.Where(resource => resource.EndsWith(fileNameInDll, StringComparison.InvariantCultureIgnoreCase)).FirstOrDefault();
if (resourcePath == null)
{
throw new Exception(string.Format("Cannot find {0} in the embedded resources of {1}", fileNameInDll, currentAssembly.Value.FullName));
}
SaveFileFromEmbeddedResource(resourcePath, outFileName);
}
public static string GetDisassembledFile(string assemblyFilePath)
{
if (!File.Exists(assemblyFilePath))
{
throw new InvalidOperationException(string.Format("The file {0} does not exist!", assemblyFilePath));
}
string tempFileName = Path.GetTempFileName();
var startInfo = new ProcessStartInfo(ILDasmFileLocation, string.Format(ildasmArguments, assemblyFilePath));
startInfo.WindowStyle = ProcessWindowStyle.Hidden;
startInfo.CreateNoWindow = true;
startInfo.UseShellExecute = false;
startInfo.RedirectStandardOutput = true;
using (var process = System.Diagnostics.Process.Start(startInfo))
{
string output = process.StandardOutput.ReadToEnd();
process.WaitForExit();
if (process.ExitCode > 0)
{
throw new InvalidOperationException(
string.Format("Generating IL code for file {0} failed with exit code - {1}. Log: {2}",
assemblyFilePath, process.ExitCode, output));
}
File.WriteAllText(tempFileName, output);
}
RemoveUnnededRows(tempFileName);
return tempFileName;
}
private static void RemoveUnnededRows(string fileName)
{
string fileContent = File.ReadAllText(fileName);
//remove MVID
fileContent = regexMVID.Replace(fileContent, string.Empty);
//remove Image Base
fileContent = regexImageBase.Replace(fileContent, string.Empty);
//remove Time Stamp
fileContent = regexTimeStamp.Replace(fileContent, string.Empty);
File.WriteAllText(fileName, fileContent);
}
public static string DisassembleFile(string assemblyFilePath)
{
string disassembledFile = GetDisassembledFile(assemblyFilePath);
try
{
return File.ReadAllText(disassembledFile);
}
finally
{
if (File.Exists(disassembledFile))
{
File.Delete(disassembledFile);
}
}
}
}
}
现在您可以比较这两个 IL 代码的内容.另一种选择是生成这些文件的哈希码并进行比较.Hese 是一个 HashCalculator 类:使用系统；使用 System.IO；使用 System.Reflection;
Now you can compare the contents of these two IL codes. Another option is to generate hash codes of these files and compare them. Hese is a HashCalculator class: using System; using System.IO; using System.Reflection;
namespace FileHasher
{
public class HashCalculator
{
public string FileName { get; private set; }
public HashCalculator(string fileName)
{
this.FileName = fileName;
}
public string CalculateFileHash()
{
if (Path.GetExtension(this.FileName).Equals(".dll", System.StringComparison.InvariantCultureIgnoreCase)
|| Path.GetExtension(this.FileName).Equals(".exe", System.StringComparison.InvariantCultureIgnoreCase))
{
return GetAssemblyFileHash();
}
else
{
return GetFileHash();
}
}
private string GetFileHash()
{
return CalculateHashFromStream(File.OpenRead(this.FileName));
}
private string GetAssemblyFileHash()
{
string tempFileName = null;
try
{
//try to open the assembly to check if this is a .NET one
var assembly = Assembly.LoadFile(this.FileName);
tempFileName = Disassembler.GetDisassembledFile(this.FileName);
return CalculateHashFromStream(File.OpenRead(tempFileName));
}
catch(BadImageFormatException)
{
return GetFileHash();
}
finally
{
if (File.Exists(tempFileName))
{
File.Delete(tempFileName);
}
}
}
private string CalculateHashFromStream(Stream stream)
{
using (var readerSource = new System.IO.BufferedStream(stream, 1200000))
{
using (var md51 = new System.Security.Cryptography.MD5CryptoServiceProvider())
{
md51.ComputeHash(readerSource);
return Convert.ToBase64String(md51.Hash);
}
}
}
}
}
您可以在我的博客上找到完整的应用程序源代码 - 以编程方式比较两个 dll 文件
You can find the full application source code on my blog here - Compare two dll files programmatically
这篇关于如何判断两个 .NET DLL 是否相同?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
