Edit: obligatory explanation (thanks mods for squaring me away)…

What you see via the UI isn’t “all that exists”. Unlike Reddit, where everything is a black box, there are a lot more eyeballs who can see “under the hood”. Any instance admin, proper or rogue, gets a ton of information that users won’t normally see. The attached example demonstrates that while users will only see upvote/downvote tallies, admins can see who actually performed those actions.

Edit: To clarify, not just YOUR instance admin gets this info. This is ANY instance admin across the Fediverse.

  • dukk@programming.devEnglish
    01·
    1 year ago

    That’s the point of a hash function. You have a public hash function, say SHA-256. It’s easy to check a username against it’s hash, but virtually impossible to reverse the hash back to the username.

    Edit: Instead of storing, say, eddie, we’d store 3b9d8298f1b5086d012618feebb2da1a394357c1dab7523443c9f6a743c4c84d. Then when the instance gets a Like from eddie, it hashes his username to get 3b9d8298f1b5086d012618feebb2da1a394357c1dab7523443c9f6a743c4c84d, realizes there’s a match, and doesn’t update the count.

    Note that when given 3b9d8298f1b5086d012618feebb2da1a394357c1dab7523443c9f6a743c4c84d, it would take millions of CPU years to compute the original username from it. Therefore, we can check for duplicates without actually checking the name itself (a similar method is used for checking passwords; Lemmy is open source, we know the hashing algorithm, but we can’t unhash user passwords, only check them).