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ed770878 / HohhaDynamicXOR

Hohha Dynamic XOR Encryption Algorithm
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Taking some time off from coding #2

Open ed770878 opened 8 years ago

ed770878 commented 8 years ago

I'm going to take a break from this project for a little while, but I'll be back. Working on the code is fine, and there is still more that I plan to do, but later.

There are two things on my todo list, in the following order:

  1. The current version of the KPA key recovery attack has a run time in the range of a few seconds to just under an hour, depending on input. I think I can do better, using iterative deepening and a value-ordering heuristic. My goal is to improve the current attack run time to under a second, and also be able to recover larger keys with more jumps in a reasonable amount of time, like under an hour.
  2. After a cursory review of the packet format, I believe that it is vulnerable to a ciphertext only attack. I have a specific design for an attack in mind. I believe that it will be able to recover the key body, the key crc, and the original key salt, given nothing more than encrypted packet headers. To be clear, what I am saying is that I believe the algorithm is less secure with the packet header than it is without the packet header.
ed770878 commented 8 years ago

I spent a couple hours on 1. It is interesting how much different inputs affect the search time. There seems to be something special about the "easy" inputs that allows search to backtrack so early in that case.