I have two questions regarding performance of John the Ripper.

Within the format files, there is a variable named MIN_KEYS_PER_CRYPT and MAX_KEYS_PER_CRYPT. How much do they influence the performance. What will be the difference between setting them to 1 and setting them higher?


When I try to crack my salted Hash (I've finally managed to implement my own format), and I try to crack a file with 3 hashes, where one of the hashes is trivial (test123 as password), depending on how I structure the file I get different outputs:

If the trivial Hash is at the bottom it'll get cracked first almost instantly. Afterwards John tries to crack the other ones.

If it is at the top of the file, John seems to start from the bottom again and only tries to crack the last hash. I won't get the first cracked in the first few minutes.

Is this behaviour normal for salted hashes? Or might something be wrong with my format?

  • Could you upload your file with hashes to a GitHub Gist or Pastebin paste :) ? Commented Feb 10, 2020 at 4:50


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