DanielIvanCorti

Binary data encryption HELP

3 posts in this topic

#1 ·  Posted (edited)

Hi all,

I need to operate on a random (long) string of bits, contained in a binary file, produced by an hardware random number generator.
I have to do a "whitening" with the very simple Von Neumann algorithm:

take the first two bits
if they are equal, discard them
if they are 1 and 0, output 1
if they are 0 and 1, output 0
take next two bits

This process eliminates bias from the string, making it ideal for cryptography purposes.
I succeded at this but in a very poor way, reading binary data (displayed as hex), translating it to an INT number and then manually to 1's an 0's AND BACK. It's extremely slow.

Do you know any more elegant way to do this? Ideal would be "to talk" in 1 and 0 from the start..
Thank you in advance,
Daniel
 

Edited by DanielIvanCorti

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The only efficient way I can see is by inlining a handfull of ASM to do that really fast. There are many examples of inline machine code in the examples forum.


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Umh, I'm so noob at this and I don't know assembly.. where to start?  Some advice?

Thank you :)

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