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Sorry to disturb...cryptopp


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Well i have been coding in assembler from the very first day i started in the scene. but now i am really getting mad with this situation...

I was reversing a software (my ideas here are doing a keymaker and cracked dll here).

basicall this thing uses cryptopp - yeah big pain in the ***. what it does is ECDSAsignatureberify("OCDE"+username,signature).the signature is your serial number.

i know this seems easy... that was what i thought too. but when i looked at it closer... omg the cryptopp libs are a total NIGHTMARE there are not any clear manuals anywhere where i really can know how this works. the signature produced by cryptopp for ecdsa is an array of bytes - how can this be if an ecdsa signature should content two parameters (r,s)?. And how can i do if want to produce a public and a private key (having defined some curve paremeters before like p,public points, a, b, cofactor and subgroup order)?. the key is BER encoded yes... i could live with it... but its really impossible to solve this without using cryptopp in my keymaker. The main thing i would like to modify would be the public point in my target. but to do so... i need to know how i can create public key parameters having the other stuff fixed.



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Possibly try Google and search for your query, then (here's the clincher) actually read through the results and see which ones are pertinent to your line of questioning:


Straight from the horses mouth, shows how to generate keypairs working with Private & Public, how to set up domain parameters, etc.

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This lib is not as hard as you think...

You can easily find ECDSA params and Curve Points by using Olly, IDA and IDA Signatures togather.

In my opinion, the best solution is to recognize functions manually (understand big number structure, EC point structure, Big Number Creation, Set EC Points, ECDSA...)

This lib's functions are very like the other libs functions, they are just coded in other way

Ofcourse, it will take a some time, but after it, you'll be able to recognize this functions in many Applications.

And its possible to make your keymaker in other languages or use other libs, bcoz all libs are doing same calculations.

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ghandi that was exactly what i did not wanted lol i can't modify the code in order to do what i described.qp^j : i liked your idea i wonder if there are signatures that may help to recognise this some internal cryptopp functions...

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