this post was submitted on 21 Jan 2024
70 points (91.7% liked)
Privacy
31991 readers
570 users here now
A place to discuss privacy and freedom in the digital world.
Privacy has become a very important issue in modern society, with companies and governments constantly abusing their power, more and more people are waking up to the importance of digital privacy.
In this community everyone is welcome to post links and discuss topics related to privacy.
Some Rules
- Posting a link to a website containing tracking isn't great, if contents of the website are behind a paywall maybe copy them into the post
- Don't promote proprietary software
- Try to keep things on topic
- If you have a question, please try searching for previous discussions, maybe it has already been answered
- Reposts are fine, but should have at least a couple of weeks in between so that the post can reach a new audience
- Be nice :)
Related communities
Chat rooms
-
[Matrix/Element]Dead
much thanks to @gary_host_laptop for the logo design :)
founded 5 years ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
Youtube never knows the private half of your key pair. That never leaves your system.
Anything encrypted with the private half can only be decrypted with the public half, and anything encrypted with the public half can only be decrypted with the private half. These halves are known as the public key and the private key. Each side of the connection generates their own key pairs.
We both generate a set of keys, and exchange the public halves with each other. I then want to send you a message: I first encrypt it using my private key, I then encrypt it again using your public key and send that to you.
In order to read that message, you first decrypt it using your private key. This ensures the message was intended for you and wasn't modified in transit, as you are the only one with access to that private key and only its matching public key could have been used to encrypt that layer.
You then decrypt it a second time using my public key. As I'm the only one with access to my own private key, you can be sure the message was sent by me.
As long as that resulted in a readable message; You've now verified who sent the message, that it was intended for you, and that the contents have not been modified or read in transit.
All this, including the key exchange is handled for you by the https (tls) protocol every time you connect to a website. Each of the messages sent between you and the site are encrypted in this manner.
This is not true. In key pair cryptography, the public key used only for encryption and the private key is used only for decryption.
As far as I understand a key pair can be used bi-directionally like I'd described. Was I mistaken?
In practice, the private key is usually used to create signatures instead, but I avoided that for simplicity.
You're not mistaken, it is definitely possible with at least RSA, though, I would guess it may not always be possible. It also sounds like it's still a bad idea unless you know all of the parameters used to generate the keys and can be sure what information is actually encoded in the keys.