How long would it take to disassemble Rybka 4?

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Dann Corbit
Posts: 12550
Joined: Wed Mar 08, 2006 8:57 pm
Location: Redmond, WA USA

Re: How long would it take to disassemble Rybka 4?

Post by Dann Corbit »

Romy wrote:
dann wrote: It would take IdaPro about a minute to turn the binary into assembly.
You could use the hex rays decompiler to get uncommented spaghetti C in five minutes or so.
I doubt if it would compile.
Correct.

Are you "Juri Osipov"?
No

That conclusion is consistent with the evidence.
So far as I can see, I have not drawn any conclusions. What conclusion does the pronoun 'that' refer to?

To the same degree that it is consistent with the evidence that Mr Rajlich stole from Fruit.
I have never accused Mr. Rajlich of stealing code from Fruit. I do not know whether he has or has not done that.
Mark
Posts: 216
Joined: Thu Mar 09, 2006 9:54 pm

Re: How long would it take to disassemble Rybka 4?

Post by Mark »

Dann Corbit wrote:
Tom Barrister wrote:I'm merely curious.

Assuming a competent programmer, with considerable experience at disassembly, and who had the tools (hardware/software/whatever needed) to do the job, were being paid to disassemble Rybka 4, approximately how many hours would it take?
It would take IdaPro about a minute to turn the binary into assembly.
You could use the hex rays decompiler to get uncommented spaghetti C in five minutes or so.
I doubt if it would compile.
So, if someone wanted to get well-organized, readable C, would they work with the spaghetti C or with the assembly?
Dann Corbit
Posts: 12550
Joined: Wed Mar 08, 2006 8:57 pm
Location: Redmond, WA USA

Re: How long would it take to disassemble Rybka 4?

Post by Dann Corbit »

Mark wrote:
Dann Corbit wrote:
Tom Barrister wrote:I'm merely curious.

Assuming a competent programmer, with considerable experience at disassembly, and who had the tools (hardware/software/whatever needed) to do the job, were being paid to disassemble Rybka 4, approximately how many hours would it take?
It would take IdaPro about a minute to turn the binary into assembly.
You could use the hex rays decompiler to get uncommented spaghetti C in five minutes or so.
I doubt if it would compile.
So, if someone wanted to get well-organized, readable C, would they work with the spaghetti C or with the assembly?
I guess both.
You would use the C to get the big picture, and then look at the assembly to get the details of what it is actually doing.

The reverse engineering tool to create C is rather expensive I think. It would seem strange to me if someone bought this tool just to reverse engineer a chess program.
bob
Posts: 20943
Joined: Mon Feb 27, 2006 7:30 pm
Location: Birmingham, AL

Re: How long would it take to disassemble Rybka 4?

Post by bob »

Mark wrote:
Dann Corbit wrote:
Tom Barrister wrote:I'm merely curious.

Assuming a competent programmer, with considerable experience at disassembly, and who had the tools (hardware/software/whatever needed) to do the job, were being paid to disassemble Rybka 4, approximately how many hours would it take?
It would take IdaPro about a minute to turn the binary into assembly.
You could use the hex rays decompiler to get uncommented spaghetti C in five minutes or so.
I doubt if it would compile.
So, if someone wanted to get well-organized, readable C, would they work with the spaghetti C or with the assembly?
Faster to take the spaghetti C. Otherwise you get to go from asm to speghetti C yourself, and then figure out how to clean it up to look like something a human would have written...