Olly Plugins


Author: David Zimmer
Date: 10.22.10 - 6:22pm



So i have been fighting with my hit trace plugin today. First let me say i really hate plugin development..it is such a long ass process to compile, install, restart host, launch plugin, configure plugin, launch process, examine results.

I have literally been at it all day!

So it turns out this plugin has been broken from the start it seems. when you are inside the ODBG_Pluginmainloop inside an EXCEPTION_BREAKPOINT handler, calls like this give you stale data

   t_thread *th = Findthread(threadId);
   t_reg tr;
   tr =  th->reg; 
   return tr.r[REG_EAX];
Thats fun to know. I tried all kinds of stuff like trying to make it redraw all the panels and what not. Finally i looked at ollyscript source and found what he did..

   t_thread* t;
   t = Findthread(Getcputhreadid());
   CONTEXT context; 
   context.ContextFlags = CONTEXT_INTEGER | CONTEXT_CONTROL ;
   GetThreadContext(t->thread, &context);

   switch(i){
	case REG_EAX: return context.Eax;
I guess i dont quite get why the olly api fails here. It must be because you are in an exception event and i just missed the memo. Sucks to be me. this was a very long painful debugging session. :(

actually in hindsight..i bet if i had set a timer and then run my handling code outside of the Pluginmainloop after like a 30ms delay everything would have been fine.

Turns out the hunch about using a timer to let Pluginmainloop return corrected the problem. This way I can go back to using Expression to eval complex expressions over the simple version i cooked up that explicitly used my own GetRegister routine. Will post a link when complete.

The update was all for adding a ascii string dumper feature to it. the things you find when you turn over rocks eghh...

Updates added:
  • ascii dump feature (prefix expression with A)
  • hexdump feature to log data (prefix exp with H, and number - H8 would specify hexdump and log 8 chars)
  • log output to file
  • support multiple trace expressions per breakpoint
  • allows you to log a comment with trace data (either from gui or disasm)
  • edit saved hittrace breakpoints
  • view hit count stats

Download: OllyHittrace.zip




Comments: (0)

 
Leave Comment:
Name:
Email: (not shown)
Message: (Required)
Math Question: 6 + 42 = ? followed by the letter: J 



About Me
More Blogs
Main Site
Posts: (All)
2024 ( 1 )
2023 ( 4 )
2022 ( 5 )
2021 ( 2 )
2020 ( 5 )
2019 ( 6 )
2017 ( 5 )
2016 ( 4 )
2015 ( 5 )
2014 ( 5 )
2013 ( 9 )
2012 ( 13 )
2011 ( 19 )
2010 (11)
     Retro XSS Chat Codes
     Exe as DLL
     Olly Plugins
     Debugging Explorer
     Attach to hidden process
     JS Refactoring
     Asm and Shellcode in CSharp
     Fancy Return Address
     PDF Stream Dumper
     Malcode Call API by Hash
     WinDbg Cheat Sheet
2009 (1)
     GPG Automation