Difference between revisions of "Talk:Research: Pwnage Patches"

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'''And the even more important question is, why is it really necessary to do reverse engineering of reverse engineering?? Could be much more simple the questions are answered by some people that tend to mystify some things... </sarcasm>'''
 
'''And the even more important question is, why is it really necessary to do reverse engineering of reverse engineering?? Could be much more simple the questions are answered by some people that tend to mystify some things... </sarcasm>'''
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said people would like to document, but most of the they're too busy using the little free time they have actually getting stuff done that people need done rather than documentation that 1% wants

Revision as of 21:37, 2 August 2008

What is more important, is the code before 1800587C.

Compilers translate actions like

if (condition is good)
then

into conditional jumps. What you can see with the MOV and NEG is most probably the result of a failed condition (-1) (or failed function result). Afterwards it depends on the compiler, how it further treats the result.

Maybe the original pseudo code is as follows:

sig_check_result = do_check(important args);
...
if (sig_check_result == 0)
    everything goes fine ...
...
a.s.o

So the question is, why it goes to the branch where R0 is set to -1 (patch 0) and what conditional branches lead to this code position? And the even more important question is, what is the underlying pseudo code?

And the even more important question is, why is it really necessary to do reverse engineering of reverse engineering?? Could be much more simple the questions are answered by some people that tend to mystify some things... </sarcasm>

said people would like to document, but most of the they're too busy using the little free time they have actually getting stuff done that people need done rather than documentation that 1% wants