I know that all assemblies can be decompiled somehow, but C# & VB applications are the easiest to be decompiled into source code using tools like ( .Net Reflector ).
So my question is, if I programmed an application using .Net assemblies and functions with C++, would it be easy to decompile it as if it was a C# or VB application with .Net reflector and such tools?
Ok, if I programmed it without using any function from .Net framework and made UI only what calls .Net assemblies, would be easy to decmpile also ?
My question is similar to this one : Could this C++ project be decompiled with such tools like a .NET Reflector?
but no one has answered him correctly, so can anyone help me ?
I want to use .Net and C++ to make my application compiled into both Native & Managed code!
There is no "C++.Net". There is C++/CLI, which is a C++-like language that can be used to glue native C++ code with the .NET world. The managed code you write in it (ref classes) will be compiled to MSIL. The "native" code will compile to either MSIL or native. If you want to compile some parts to native code you need
#pragma managed(push, off)
void foo() {}
#pragma managed(pop)
in your source. The managed pragma can be used to choose the compilation target per-function. Or you can compile without the /clr flag per-module and set your project to produce a mixed-mode assembly.
Be aware that marshaling the native types to .NET and back can take a serious performance hit on your application - and that happens every time you cross the native-managed boundary. But interoperation between such embedded native code and managed code is much faster than normal p/invoke.
See also this question: C++CLI. Are native parts written in pure C++ but compiled in CLI as fast as pure native C++?
Related
We have a Visual Studio solution with about 90 projects. Most of them are built to DLL files, some are written in C++, others in C#. The projects communicate with each other via COM. We use tlbexp to generate TLB files of some C# projects (the ones that are referenced in C++ projects). And we use tlbimp to generate interop DLLs of the C++ projects. I did not completely dig into the topic, but I think, the interop files just define the interfaces of the C++ classes, to make them usable from other projects is that right?
Now, the question is the following: In order to upgrade the entire solution to Visual Studio 2015 and let it compile against .NET 4.6.1, I inspected the resulting assemblies using dotPeek by JetBrains. I can see, that all the C# projects are correctly using .NET 4.6.1, the C++ DLLs themselves are native and do not reference any .NET. Now, what surprised me was the fact, that dotPeek told me, the interop DLLs (which resulted from the C++ projects), were referencing .NET 4.0.
After a "wonderful" day of trying to make them reference .NET 4.6.1 and lots of research, I finally did not find any way to make the interops reference .NET 4.6.1. Is that even possible? My current guess is, that all interop DLLs generated like this reference just the basic .NET 4.0, just because it uses the same CLR as .NET 4.6.1.
Is that right? It should be possible to execute the assemblies on any system that has .NET Framework 4.6.1 installed, shouldn't it?
You are getting bad info from dotPeek. It doesn't tell you how it figured out what .NET version is targeted. It can be specific on a .NET assembly that's generated by a compiler. Because it automatically inserts a [TargetFramework] attribute into the assembly, it states what version of .NET you selected when you built the project.
But an interop assembly does not specify a .NET version, primarily because it isn't generated by a compiler. Note how you never specified a version when you ran Tlbimp.exe. And can't. All that dotPeek can figure out is that it targets .NET 4, cued by the metadata format. No way it can be more specific.
And it does not matter, since the interop library does not use .NET Framework features. The only point of the library is that your program can use the COM component features. So the version number that dotPeek reports just doesn't matter; any .NET 4.x framework can use the library.
You don't have a real problem.
I have a strange CLR OutOfMemoryException in a 64bit C++/CLI process which has mixed native and managed C++ code inside. The process has the following structure:
Native C++ code (Main binary)
Managed C++/CLI code (Main binary)
C# code (External assembly)
Both main binary and external assembly are built for x64 platform. The managed C++/CLI layer (2) serves as an adapter between native C++ code (1) and C# code (3) which is actually a UI layer working with WPF. .NET Framework version is 4.0.
So I have the Main Binary (1 and 2) built with /MACHINE:X64 and /CLR which makes native C++ code (1) to work perfectly with >4Gb of memory consumed by the process, but C++/CLI layer code (2) throws an OutOfMemoryException once I step close to 4Gb. So far it happens in relatively random places but every time I saw it was in Managed-to-Native transitions when C++/CLI code tried to access a native method.
It seems like C++/CLI code inside Main binary doesn't feel itself as a x64-ready code, while the tools tell that the binary is in PE+ 64bit ready format and the native code works well with >4Gb. According to ANTS memory profiler and CLRProfiler the managed heaps are almost empty (several hundred of kb).
What could I miss? Doesn't it look like I'm linking to wrong .NET framework assemblies which are not x64-ready? Where should I look first?
Thanks in advance for any help!
I have an executable I made using a CLI console application with Visual Basic 2010. I can run the program completely fine from my developer machine.
However, when I copy the executable over to another machine, re-boot to a pre-installation environment and run the executable again, nothing happens at all. There are no errors shown or anything.
My guess is the executable can't run without certain dependencies that aren't loaded at this environment, but I need it to work in a PE.
Any ideas on whats going on?
First of all, since the question is tagged "c++" and you mention C++/CLI several times, I assume that "Visual Basic 2010" is a typo for "Visual Studio 2010". But either way, whether you've written the application in Visual Basic (VB.NET) or C++/CLI, the problem is exactly the same.
My guess is the executable can't run without certain dependencies that aren't loaded at this environment, but I need it to work in a PE.
That's exactly correct. You've written an application that targets the .NET Framework. Somewhat like Java applications requiring a JVM, .NET applications require that the .NET Framework be installed in order to run (or a compatible alternative implementation, like Mono). Unfortunately, Windows PE does not support the .NET Framework.
Note that it is irrelevant whether you've written a WinForms, WPF, or Console application. Although they present their UI in very different ways, they all depend on the .NET Framework being installed.
You will need to (re-)write the application in a different programming language, one that generates native code without any dependencies on the .NET Framework. C and C++ are popular choices. If you choose to use C++, make sure that you create what Visual Studio calls a "Win32" project. This is one that targets the underlying operating system APIs directly (i.e. a native application) and does not have a dependency on the .NET Framework. Stay away from anything that has ".NET" or "CLR" in its description.
I don't really have a full comprehension of when an application is using .NET or not... I am just used to Linux C/C++ development. I hate Microsoft shit
It uses .NET whenever you use the .NET Framework libraries/classes in your code. I'm not really sure why this is so difficult to understand. The same problem could easily exist on Linux if you were using a third-party library that was not available in certain environments for whatever reason. This is not Microsoft's problem, it's an issue of using the wrong tools for the job. The .NET Framework is an object-oriented wrapper around the native APIs that makes it much easier for people to get up and running writing programs for Windows. But if you're "used to Linux C/C++ development", you should have little trouble writing a simple console application that targets the native APIs directly without using .NET.
If your hatred for "Microsoft shit" has turned into an allergy, you can avoid Visual Studio entirely and download MinGW, which is a Windows port of the GCC compiler you're probably used to. Combined with your favorite Windows port of Vi, you're working in an environment very similar to the one you're used to. And since GCC doesn't support C++/CLI or the .NET Framework, you won't have to worry about getting stuck picking the wrong option.
The .Net framework has been supported as an optional package install during your PE build process for the past couple versions of WinPE. I write code in C# that I run in WinPE everyday. I have yet to find a good way to debug in a manner where I can walk through break points, etc... though. My best option has just been a lot of logging and a global Exception catch around my main entry point that will write out a full stack dump. You can attach to your app as a remote process in a VM running WinPE, but if you need to catch something early in the execution you'll have a difficult time.
I saw some Youtube videos that claimed they showed how to build a C++ applications using Winforms.
As far as I knew you needed something else like QT. Is it really possible to build using the same WinForms you would use to build a C# application but with C++ instead?
WinForms is managed code and is usable from practically every language with runs on the CLR. So standard native C++ can't build a winforms app. However managed C++ or C++/CLI can build WinForm apps in native code.
In general though I would question why you were doing this. If you are willing to have mixed mode C++ it would probably be much faster to
Build the UI in C#
Communicate with your native backend through a mixed mode C++ layer.
In VS ('05), you can go to File->New->Project... Then Visual C++ -> CLR -> Windows Forms Application. Have fun :)
Native exe!
that means my program can run easily without any requirement?
even if I use .net classes?
You know I want to write a program that is so light and I don't like to use C# or any other .net programing language because all of them need .net-framework 4.5.
Just think a 2.5 MB programm needs a +250 MB .netframework.
New Update - 12/01/2016:
It's almost 4 years ago when I asked this question. As you know Dotnet Native is announced. It's an interesting feature which compile IL into native code.
Compiling Apps with .NET Native
.NET Native is a precompilation technology for building and deploying
Windows apps that is included with Visual Studio 2015. It
automatically compiles the release version of apps that are written in
managed code (C# or Visual Basic) and that target the .NET Framework
and Windows 10 to native code. Typically, apps that target the .NET
Framework are compiled to intermediate language (IL). At run time, the
just-in-time (JIT) compiler translates the IL to native code. In
contrast, .NET Native compiles Windows apps directly to native code.
For developers, this means:
Your apps will provide the superior performance of native code.
You can continue to program in C# or Visual Basic.
You can continue to take advantage of the resources provided by the .NET Framework, including its class library, automatic memory
management and garbage collection, and exception handling.
Last I checked none of the .NET frameworks were 250+ MB! Yes, the offline installer for .NET Framework 3.5 SP1 is 231MB but it contains x86 and x64 versions of .NET 2, 3 and 3.5 sp1.
You should read this http://www.smallestdotnet.com for details on sizes of various versions of the installers.
Now on to your question:
Yes, It is a little annoying to have your clients install a big framework, even 20-40MB does get annoying. With .NET, the advantage is the ease of programming (In my opionion) compared to other Native options.
Your native options are:
MFC - You need only the VS runtimes installed, which is 1-2MB and is usually installed on newer pcs. Also, you can ship your application with the MFC libraries packaged into a dll which is again <2MB
The trade of here is you need to program in C++, the libraries overall are a very thin layer over the native libraries. and people have had harsh opinions about MFC. I've barely just tried it.
Win32 API - This is going all bare bones, and quite difficult, you could use C or C++ but you'd really have to know a lot about the Win32 API and how windows itself works (Stuff like windows messages, hwnds etc) Its not fun, believe me. But during deployment you would not need any external libraries.
There are tons more options, see here:
Native Windows Application Development Options
https://stackoverflow.com/questions/2711599/what-programming-language-should-i-use-to-create-small-native-windows-applicatio
Here are some links on MFC that might help:
Want to learn Windows Programming,some suggestions?
How do I decide whether to use ATL, MFC, Win32 or CLR for a new C++ project?
C++ MFC vs .NET?
https://stackoverflow.com/questions/557114/stick-with-mfc-or-go-to-net
you are able to create native exe by using c++ Win 32 projects.
Alas, nearly everything requires a download runtime library and even if you have one installed, you'll need to download updates for them almost continually. Even Microsoft C++ apps nowadays come with security updates that have to be installed if you've compiled your app with them.
But.. there is a solution of sorts. If you use C++, it has a feature where only the things you use are compiled into the final app. Normally, this would require linking with all the library dlls, but if you statically link with the library, you will end up with a single .exe that is as small as can be, and you will not need any dlls (as all the code contained in the library will be compiled into the .exe).
The benefits are debatable compared to dlls, but as MS has pretty much broken the idea of shared dlls in .NET (ie, you practically have to put all the shared dlls in the same directory as your running app, giving you a nightmare in maintenance if you have these shared dlls spread around all your apps) then there's not much of a difference anymore. Static linking is getting a little bit of a comeback and sounds like its what you want.
For modern C++ development, you'll probably want to take a look at Qt instead of MFC. Its a lot nicer to use and is cross-platform so you can run Qt apps on your Android or Linux platforms as well as Windows.