cpressercccpresser@chaos.social
Oct 20, 2026, 4:14 PM@q ELI5? I have almost zero knowledge in crypto and don't understand it.
Replies
srslypascalsrslypascal@chaos.socialOct 20, 2026, 4:39 PM
Oct 20, 2026, 4:39 PM@cccpresser the private key for a certificate that can attest for other websites (super super secret) is the number 4
yes its as stupid as it sounds
Oct 20, 2026, 5:45 PM@cccpresser cryptography, basically, is doing math with input data, and a secret number. You want secret number to be big and random, so no one could guess it and undo your math
number 4 is, obviously, neither big nor very random...
rzeta0rzeta0@mastodon.worldOct 20, 2026, 6:47 PMI'm no expert so tell me where I'm wrong:
1. If you have a large range from which to choose a number randomly then 4 is entirely possible.
2. The criterion is a number hard to factor.
Is that right?
Grant Gouldnonnihil@hachyderm.ioOct 20, 2026, 6:58 PM@rzeta0
I don't think factoring is relevant here -- it's not RSA, it's a different annoying function to invert -- but I do think that ending up with such a distinctive number 4 seems unlikely to have been random.- Oct 20, 2026, 7:12 PM
@rzeta0 @mo @cccpresser 2 is only true for RSA keys, this is ECDSA
Simon Brookesimon_brooke@mastodon.scotOct 20, 2026, 7:46 PM@mo @cccpresser @q strictly speaking, 4 is exactly as random as any n such that n is a member of the set of natural numbers.
But it's not exactly as likely to be tested by an adversary as any other..
mxkmxk@hachyderm.ioOct 21, 2026, 5:08 AM@simon_brooke it's random but it's easy to guess.
Realistically you want a certain size requirement here, just like you don't pick small primes with RSA, no matter how random they are.
Pete Alex Harris🦡🕸️🌲/∞🪐∫petealexharris@mastodon.scotOct 21, 2026, 7:36 AM@mxk @simon_brooke
OMG is this literally a realisation of this old joke in real life?int random() {
// guaranteed random: obtained by dice roll
return 4;
}