# Looking for algorithm idea help

• November 18th, 2010, 12:28 PM
Maineiac
Looking for algorithm idea help
I'm trying to solve a puzzle: I've been given a bunch of sets of String/Key/Hash trios, and I need to figure out the hash function that generated each Hash from the given String/Key.

I'm stumped. Thoughts?
• November 18th, 2010, 02:02 PM
aussiemcgr
Re: Looking for algorithm idea help
Can you give an example of what it looks like when you start, what parts of that example you get, and what it should look like at the end?
• November 18th, 2010, 02:16 PM
Maineiac
Re: Looking for algorithm idea help
Quote:

Originally Posted by aussiemcgr
Can you give an example of what it looks like when you start, what parts of that example you get, and what it should look like at the end?

Here are a couple of examples:

String: d ac2b1f3e4 ce5db ac3 71a24b
Key: 123456789abcdef
Hash: d0ac2b1f3e40ce5db0ac371a24b

String: d ac2b1f3e4 ce5db ac3 71a24b
Key: abcdef
Hash: 38116765f7a4cb1fb192

Then:
Hash: 141205a0fc9314af2fcac1c7136823f422f1bfe645bb783376 aa8926e48e41118260ceaf4a424a6b0ec7eedfbafed298ffc6 43142c80c081b23cfdb59d741a44248db96e18819034a5f46f 4b4af5

Key: 50nd4l)E16i28T3aC9L7DfcbeU(IBvtNAy

String:?

Thanks for looking
• November 18th, 2010, 02:49 PM
copeg
Re: Looking for algorithm idea help
I do not think what you wish to do is trivial, and I am curious as to why you wish to do it in the first place (I ask because things typically get hashed for a reason, and the first reason that comes to mind why one would wish to backwards engineer the hash function is to hack something).
• November 18th, 2010, 04:17 PM
javapenguin
Re: Looking for algorithm idea help
Quote:

Originally Posted by copeg
I do not think what you wish to do is trivial, and I am curious as to why you wish to do it in the first place (I ask because things typically get hashed for a reason, and the first reason that comes to mind why one would wish to backwards engineer the hash function is to hack something).

Has anybody ever tried asking for help to hack something here before?
• November 18th, 2010, 06:38 PM
copeg
Re: Looking for algorithm idea help
Quote:

Originally Posted by javapenguin
Has anybody ever tried asking for help to hack something here before?

Any hacker with their head on straight is not going to straight out admit it, but there are red flags that makes one wonder what the actual intent is (such as this). For all I know the original poster has a logical reason for wishing to generate an algorithm like this, which is why I asked.