forum.vdsworld.com

FreezingFire · **Admin Team** Joined: 23 Jun 2002 Posts: 3508

How can I find the callable APIs in a DLL? I heard that there used to be
a function in Windows that did this but now it's not in XP. Sad

My problem is that I want to find the functions in a DLL that's not
documented so that I can call them.

Thanks for any help in advance! Very Happy

bbelcher · Contributor Joined: 30 Jul 2002 Posts: 172

FreezingFire · **Admin Team** Joined: 23 Jun 2002 Posts: 3508

Hmm, thanks bbelcher Very Happy

, but I need a tool that will give me more information.

Does anyone else know of any such tool?

Tommy · Posted: Sat Jul 26, 2003 11:28 pm Post subject:

Personally I don't think there's any way to extract more from the DLL file related to
a function than its name and address. Only if disassembling the file, I think it may
be possible to decipher information related to the expected parameters and return
values, but that would probably be very hard and possibly forbidden.

I still do find the PEBROWSE tool very valuable though and will add it to the Resources
section.

vdsalchemist · Posted: Sun Jul 27, 2003 2:52 am Post subject:

Tommy is correct. I don't think this is possible either. The only way to really do that is to disassemble the DLL. I have searched for a way to get the parameters from a DLL for the past 5 years and I have yet to find one. If someone comes up with a way to do this please tell me short of disassembling the DLL. I don't want to disassemble a DLL because that is against the license agreement from most DLL's. So for now you will have to contact the author of the DLL to get the parameters.

CodeScript · Posted: Sun Jul 27, 2003 3:13 am Post subject:

If you want just the dll functions which are exported you can use dependency walker which comes with visual studio - if U have access to one(my friend has it).
But getting parameters is almost impossible unless the author of the dll says expressly that you can decomplile it - never happens - in that case he gives away the source. If U have the header file(e.g. .h file in C++) you can see the functions and parameters directly.

But if the functon is simple you can sometimes guess what it may take - Even a beginner like me has beeen sucessful sometimes(twice) especially if U have another dll which is atleat a little similar to it.
This may help in your guessing.If U have something like:
FnDll@10. The 10 is the total size in bytes of all the arguments.

(I heard there are utilites which give you the number of parameters which the dll needs(not the exact parameters) - dont know more about it.)

But as far as API's are concerned U can have lots of documentations available e.g. APIViewer 2003 gives you the latest ones which are not present in the W32HLP file.

Regards

bbelcher · Contributor Joined: 30 Jul 2002 Posts: 172

dependency walker is also availible in the nt resource kit.

jules · Posted: Thu Jul 31, 2003 3:32 pm Post subject:

I presume you have the Windows API help file?

FreezingFire · **Admin Team** Joined: 23 Jun 2002 Posts: 3508

Yup I've got that. But there's DLLs that aren't documented in the Win32
API help file, and I don't know which functions they contain.

Skit3000 · Posted: Fri Aug 01, 2003 8:39 am Post subject:

FreezingFire, you might do a search on Google like "dllname.dll+api". That way I found some APIs for winsock (which I can't get to work), which I couldn't find at the MSDN library...

jules · Posted: Fri Aug 01, 2003 9:13 am Post subject:

You might be better off using wininet, which I think one of the API examples that comes with VDS 5 uses that. I can't remember where I got the documentation about that (certainly used Google). But most DLLs, if they aren't publicly documented, you can't be sure they will be on a user's machine and you probably won't be entitled to distribute them with your application.