Hi,
Can someone assist me with how i might go about decompiling or viewing a dll, making changes to it and recompiling it? What tools can i use to do this?
I have tried copying some of the dlls from my device over to my local pc, however most of the time i get an "access violation" message.
Further, i realize i can use idlasm to disassemble .net files, but it seems most of the more interesting dlls and files may be standard c dlls. How can i take a look at the code in these and modify if wanted?
thanks much.
farseer: what level of experience do you have?
V
I'd like to think i am decent developer, but that may be in my own mind
However, i do not do a lot of "hacking", i.e., have not had the need to do much reverse engineering. I have been coding ground up apps for over 10 years however, uisng C++, Java, C#, VB, etc. You name the language, and i've probably done something in it .
vijay555 said:
farseer: what level of experience do you have?
V
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was that the wrong answer?
farseer said:
I'd like to think i am decent developer, but that may be in my own mind
However, i do not do a lot of "hacking", i.e., have not had the need to do much reverse engineering. I have been coding ground up apps for over 10 years however, uisng C++, Java, C#, VB, etc. You name the language, and i've probably done something in it .
vijay555 said:
farseer: what level of experience do you have?
V
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The correct answer should be "I know ARM assembler language, the structure of Win32 PE files, I know what is XIP DLL and why I cannot modify them directly, and I have read the WM5 source code".
In this case the process is simple - you decompile a DLL with IDA (www.datarescue.com), find the place you need, modify the code to suit your needs - and that is all. In most cases there is not enough place in DLL for your code, so you need to use virus-like techniques, my prefered method is to patch the code so that it loads my DLL and run it instead of original code. Or use some other hooking methods so that my code is executed instead of original.
Ah, thanks much, this was helpful. I do have a few follow up questions:
1. Is "Arm assembler" different than standard assembler? If so, any suggested readings?
2. There are some dlls that cannot be copied to my local pc (i get an access violation i believe). How does one extract an image of such dlls?
3. Where is the WM5 source code? and why would i need to read this to be able to hack/patch dlls?
thanks again.
mamaich said:
The correct answer should be "I know ARM assembler language, the structure of Win32 PE files, I know what is XIP DLL and why I cannot modify them directly, and I have read the WM5 source code".
In this case the process is simple - you decompile a DLL with IDA (www.datarescue.com), find the place you need, modify the code to suit your needs - and that is all. In most cases there is not enough place in DLL for your code, so you need to use virus-like techniques, my prefered method is to patch the code so that it loads my DLL and run it instead of original code. Or use some other hooking methods so that my code is executed instead of original.
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Hi farseer!
I am nowhere near the level of mamaich or vijay555 but I have some experience in this and I believe I can give you some basic answers:
1. ARM is a different architecture then x86 processors and the assembler is different to accommodate it. There are some basic similarities like mov add and such, but even the registers are different (R0 - R15 if I am not mistaken). Sorry, I don't know any books on it, but if you google you will quickly find the list of commands with basic explanation.
2. Since the OS is in ROM you can't just copy and paste it's DLLs and EXEs. Look for ROM dumping tools on this forum, or already extracted images on the ftp. Keep in mind MS did some tricks to save memory and make it harder to get at the files, so like mamaich said, you need to learn about XIP and the ROM structure in general to understand whats going on.
3. Hmm... MS does have a program for sharing most of WM source code, but it's not for common people like us. (check out their site to see what I mean) I suspect there are other sources of getting the parts necessary to understand DLL hooking, but I have no idea what they might be.
Well that's my two cents until an expert can answer you. Hope this helps.
farseer: you gave a perfectly good answer IMHO, just needed to get an idea of what level to pitch a response without talking up or down to you!
It's well documented that I'm a self confessed newb to c++, and would say that your programming skills should certainly hold you in good stead. However, having a good knowledge of the Win32 API is certainly beneficial.
For decompiling, basically IDA. There is an IDA demo available on their website that should get you going, it's pretty much 100% functional other then it won't save, and closes itself (or crashes itself) after a reasonable, random period of time. IDA is "the daddy" for pretty much all mainstream reversing, although you could write your own decompiler/debugger.
Recompiling - that's a toughy. IDA won't permit recompiling on ARM AFAIK.
You'll have to hexedit into the target and patch directly. Otherwise you get into the exciting world of code injection, hooking etc, as Mamaich says.
For that area, read everything he's ever written, before you start reversing
Oh, and a helpful hint to all. Don't just read what Mamaich's written on this board, his posts on other boards are even more useful!
It's worth getting a good familiarity with reversing on x86 first, get used to how IDA works etc (and Soft Ice is very useful to give a good insight into x86, although AFAIK it's not available for WinCE). ARM assembler is different, but just grab a list of the opcodes and read through a few CPU developers' guides (online).
There are a number of tutorials on reversing ARM stuff online. In the usual places for that kind of stuff.
For getting access to the ROM files, easiest way is to grab a rom update file and decrypt it. Mamaich is once again your man, his romtools do the job. He also has a "live" rom grabber, that'll grab all the files/modules out of your running phone for your perusal.
Platform Builder is available free to give you (some) WinCE source code. Not all, but enough to give you years worth of reading.
V
Thanks all...very kind of you to respond in such detail. I look forward to dabbling a bit with IDA and some of mamaich tools. I suppose the first order of business is to do a lil more research and then just dive in! It's been a while since i wrote any assembly code (not since college!), but i am a bit excited at having an excuse to do so again.
thanks again.
Just remember that unless you really luck out and the developer left the symbol table intact, you're going to end up with garbage for the names of variables and subroutines.
I hate reading decompiled code.
I had developed a software. The software are using the external dll library, how can I compile the exe embedded *.dlls??
PS: I am using a VS 2005, Language: VB.net
Also I would like to know how to protect my application code avoid the decompiler to decompile ???
sorry for my poor english.
Welcome to the forum.
Your English is fine, but unfortunately there is no simple answer to your questions.
I will start with the last one first:
There is no one simple way to protect your code. There are whole books and articles written on it and if you google you will even find commercial products that "scramble" compiled apps to make it difficult to disassemble and reverse engineer.
Unfortunately I can not give you more specific info like book titles since I am not too interested on the subject.
I can tell you this: whether you app gets hacked or not is a matter of how much it costs vs. how useful / desirable it is. That means that if your program is really grate and everyone wants it but it costs a lot someone will put in the effort and eventually crack it no matter what you do.
As for your first question: unless you have source code or the obj files for the DLL to link to there is no way to combine it with your exe. If something was released as a DLL library and only as a DLL library it will remain just that.
Like mentioned above; the only possibility to 'protect' your .NET application is to obfuscate the code. there are some good (but commercial) tools out there. Google for it and if you're lucky you can find a comparison as well. (hopefully somebody tested some tools already to compare them)
You cannot recompile a DLL unless you've the source code as well.
it's easier to do if one dont use .net
Good evening! I just released the source for my very own slimserver client for windows mobile! (I was very frustrated as I couldn't find any free/open source ones out there).
This is the first release ever, and hence very very basic. Thus, I have only released the source, and no binaries..
It does work, and it does satisfy my current requirements, so I don't plan on spending a lot more time on it. If you want to see it evolving to meet your own needs as well, please do help, by donating your time and coding skills
In order to make it work , you will have to manually edit the libslim\core.cs file with your slimserver details.
There are no GPL notices, nor attributions in the files yet for the various pieces of code that I used. This will change soon!
The scrolling list control is called Kinetic Scroller, and I found it on this forum. Many thanks to dosfan for releasing the source to that excellent and extremely usable control (I did some minor changes).
I found what was the basis for SlimXML somewhere on the web, I don't remember where. Many thanks to the developer In order to compile it, you might need Visual Studio 2008.
You will also need SlimServer version 7 beta installed, as the previous versions do not provide any CLI functionality for browsing the music folders
https://sourceforge.net/projects/pslimclient/
Nice..
This sounds great. Currently I am using the handheld skin and mplayer. It works but a real client would be sweet. The only problem is I don't think I can get a C# compiler. Do you know of a free one or would you be able to get me a binary? I'm running duttys 6.1 on a at&t tilt.
Thanks and good luck with the project.
wr420
I'm not a programmer, I just want to compile MAME for the Android. But, of course compiling code within the Android platform is not possible (as one would do it in Ubuntu or Debian), so I need the Android SDK and enough knowledge of java to call the native code, which needs to be packaged by the NDK, launched from within Cygwin.
Seems there will also be some video issues, beyond my comprehension. MAME developer R. Belmont posted this on porting MAME to Android:
The OpenGL support won't help you with GLES, that'll need to be an entirely separate code path
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Whatever that means, it sounds like a lot of work. Looking around for similar projects for examples on how to call native code like the source for MAME , I found the java activity source code for aDosBox. It's also an emulator, but also has video requirements and uses native source as it's base. I'm still decrypting what it does, but for a developer (perhaps you!) looking to port MAME, it might be a good place to start.
What would be cool, is a couple templates I could just plug the needed particulars into. One for the Android.mk file that adds any required libraries needed for video stuff when I use ndk-build, and one for the java activity that simply calls the native code.
The MAME source code also has an SDL backend in the included build system. The build system 'detects' what platform it's on and builds accordingly. Can SDL be used in the Android SDK?
.NET decompiler with support for XAP applications. Allows hackers developers to decompile assemblies and resources in a code editor, make changes and compile the code back to the assembly.
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View on GitHub
Features:
Decompile .NET assemblies to C# and allow editing/compiling the high-level code back to CIL
Edit CIL instructions in method bodies
Modify assembly structure
Edit and extract assembly resources
Edit the contents of a XAP by adding, removing or swapping files, or using internal editors for certain resource types.
Integrated editors for text, hex, manifest, resource, XML and XAML.
XAP package manager (compatible with Windows Phone and Silverlight applications) allowing to view and extract XAP contents.
Does laundry, has mastered Italian cuisine, cleans and makes mind-blowjobs when asked kindly and treated right.
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Some of your skills that could be useful may be:
Blogging: You can write down the results of your testing, your ideas and stuff about .NET Rain the way you see it.
UI/UX design: You don't have to bother with WPF implementation. Photoshop designs are good enough.
C#/WPF programming: You can contribute to the code quality and all user-related features of the application.
C# Reflection mastery: The "core" is in a very alpha state and is full of bugs. The are many planned new features, too.
Donations: They will be wisely spent.
Crowd-funding experience: You can help with raising money to pay for community-hired professionals to write code that will later remain open-source.
Virgin goat blood: For recreational uses.
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Not going to lie, I laughed at that last part in the description. Very good work. Thanks for sharing!
I laughed at the git hub title for DLL editing : DLL Deep Throat XD
lol WUT!
Edit : Screen****s ? XD
jepp nice way to word some things , but please let us not use the kind of words here
and yes real good jop
I live to serve the forum rules, so fear not. GitHub is quite liberal, on the other hand
Let me know how do you like it because as of a while I'm experimenting with great new substances.
The effects of which include, but are not limited to, reviving this old project into The Tool for Windows 10.
So I'd love some (a lot of) "pre-"feedback. Try it out. Open issues on GitHub. Help me make it awesome.
Cheers