I saw that people on the dark web would sign their posts with a PGP key to prove that their account has not been compromised. I think I understand the concept of how private and public keys work but I must be missing something because I don’t see how it proves anything.

I created a key and ran gpg --export --armor fizz@… and I ran that twice and both blocks were identical. If I posted my public key block couldn’t someone copy and paste that under their message and claim to be me?

  • dohpaz42@lemmy.worldEnglish
    2·
    1 year ago

    You’re not though. You said encryption occurs with the public key and decryption occurs with the private. That’s the opposite of what happens and what the quoted text says.

    From the same source:

    In a public-key encryption system, anyone with a public key can encrypt a message, yielding a ciphertext, but only those who know the corresponding private key can decrypt

    • Crul@lemmy.worldEnglish
      11·
      1 year ago

      You said encryption occurs with the public key and decryption occurs with the private

      I’m sad that I edited some typos on my original message because now you will probably think I changed it. But I said the opposite.

      Anyway, there is probably some missunderstanding here and I don’t think this conversation is useful.

      Thanks for the feedback.

      • dohpaz42@lemmy.worldEnglish
        1·
        1 year ago

        Funny story: you didn’t change the wrong info. The sad part is that you’re spreading misinformation and unwilling to hear otherwise. This is more dangerous than helpful.

        • uberrice@feddit.deEnglish
          2·
          1 year ago

          How is Crul wrong in anything other than the terminology? You sign a document with your private key - generating basically a hash of the document entangled with your key information. Anyone holding the public key can then verify that hash with the public key - that the document contents are intact and unchanged (from the hash), and generated by the person holding the private key (entangled key information)

          • Crul@lemmy.worldEnglish
            1·
            1 year ago

            Thanks for mediating!

            What I’m getting from this dicussion is that, when signing, the operations are not encryption and decryption, but … hashing and hash-veryfing?

            • TauZero@mander.xyzEnglish
              0·
              1 year ago

              To help you with the terminology, the names for the two operations are “signing” and “verifying”. That’s it.

              What can you do with…

              public key private key
              Encryption: encrypt decrypt
              Signature: verify sign

              “Signing” is not at all the same as “encrypting” with the keys swapped. It is a separate specific sequence of mathematical operations you perform to combine two numbers (the private key and the message) to produce a third - the signature. Signing is not called “hashing”. A hash may be involved as part of the signature process, but it is not strictly necessary. It makes the “message” number smaller, but the algorithm can sign the full message without hashing it first, will just require computation for longer time. “Hash-verifying” isn’t a thing in this context, you made that name up, just use “verify”.

              @dohpaz42 is mad because you messed up your terminology originally, and thought you were trying to say that you “encrypt” a message with the private key, which is totally backwards and wrong. He didn’t know that in your mind you thought you were talking about “signing” the message. Because honestly no one could have known that.

        • Crul@lemmy.worldEnglish
          11·
          1 year ago

          Sorry, I’m very confused. Both of us seem very confident in our positions, so clearly one of use is c/confidentlyincorrect…

          I will wait until a third party helps us identify who is wrong and I will be very happy to correct any mistake if that’s the case.