Writing a Simple Password Generator in Racket

Re:Writing a Simple Password Generator in Racket by bjoli on Friday March 08, 2019 @06:31AM (#19336668)

I made this: https://pastebin.com/kQhKexEd in 5 minutes. It is however slightly off with the random distribution since I am only doing a simple remainder.

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Re:Writing a Simple Password Generator in Racket by andreareina on Friday March 08, 2019 @07:44AM (#19337022)

    (let ((byte (remainder (get-u8 urandom) size)))

is skewed if size isn't a power of 2. What you should do is mod by the next-largest power of 2 (e.g. if size is 82, mod by 128). Then if the result is in-range use it, otherwise discard and reroll.

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Re:Writing a Simple Password Generator in Racket by bjoli on Friday March 08, 2019 @07:48AM (#19337044)

I just edited the comment before I saw your answer. I realised my mistake and wanted to sink through the earth. Everyone has brain farts, I guess.

What I ended up doing was limiting the charset size to 256 a maximum of characters, and then discarding any value that is larger than the current charset.

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