this post was submitted on 03 Nov 2023
306 points (87.5% liked)
Technology
59629 readers
2874 users here now
This is a most excellent place for technology news and articles.
Our Rules
- Follow the lemmy.world rules.
- Only tech related content.
- Be excellent to each another!
- Mod approved content bots can post up to 10 articles per day.
- Threads asking for personal tech support may be deleted.
- Politics threads may be removed.
- No memes allowed as posts, OK to post as comments.
- Only approved bots from the list below, to ask if your bot can be added please contact us.
- Check for duplicates before posting, duplicates may be removed
Approved Bots
founded 1 year ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
The advantage - from my very incomplete understanding - is that your passkeys cannot be phished or stolen from you. So only you from your device can log-in to the site. Which leaves me with the question, how cross-device passkeys work.
There are different ways.
One way is to use an encryption module on the device that, rather than storing the keys just encrypts the keys and holds an encryption key that you can't extract, and can do various crypto operations.
Now you ask the module to do a secure key exchange algorithm with the new device, meditated by a party the module trusts, like apple or something.
Now both devices share a secret key, and they trust that the other is owned by the same user because the owner verified with apple who then signed the exchange messages.
Old device decrypts with the old key, and encrypts with the new key, never letting the data leave the secure module. Send the data to the new device which can do the reverse, and both devices forget the shared password.
Overall, minor weaknesses like storing keys in the cloud encrypted by a key derived from a password that the cloud never sees, while objective weaknesses, are still significant net improvements to security over passwords.
Thank you for explaining. That's a thing most sites leave out: tell people how the keys cannot be stolen while still working on a different device.
Big reason for that is the spec for how this all works being around for a while, giving people a lot of time to write about the core of how it works, but the viable popular implementations are far newer, so articles still haven't been updated, and doing the key transfers is still one of the newest parts that the big vendors don't want to talk about yet, because they still have to get their patents fully approved and everything.
What I described above is one way to move data between two devices in a secure way with a trusted intermediary to verify identity, but I have no idea if it's how any major vendor actually does it, because they haven't made that data public. It's just what's obvious to a sufficiently informed subject matter expert.
That would be a really nice advantage but yeah, I wonder how cross-device passkeys or recovery passkeys would work