Dnia sobota, 17 stycznia 2015 11:22:02 Mirimir pisze:
On 01/17/2015 03:52 AM, rysiek wrote:
So,
Mirmir wrote:
| 13. Targeted attacks against PGP key ids are possible
This is an advantage of Keybase. Then we're not depending on the KeyID, or even on the fingerprint, but rather on an identity that's multiply and independently authenticated.
I keep hearing more and more about keybase, and I have a problem with it. It's a centralised service, owned and controlled by a single entity; moreover, the keys are tied to online identities controlled by corporate third parties (Twitter, Facebook, et al). I don't see a Diaspora/The Federation support, for instance.
As I understand it, Keybase is an API. The website/service is merely a demonstration. The developers are aiming for mass adoption, and so they've targeted the most popular sites. With some coding, arbitrary sites could be used, with two requirements. First, it must be possible for users to post persistent signed proofs. Second, it must be possible for the API to access those signed proofs, in order to verify them.
My problem with this is two-fold:
1. It might allow abuse, esp. MITM attacks. If Keybase becomes a /de facto/ standard of acquiring keys, it seems trivial to me for them to replace a valued target's key with something a LEA would provide.
That's the value of trackers. Those tracking such a comprised target would see that various public signed proofs are no longer valid for the target's key on Keybase. The adversary could alter all of the target's public signed proofs. But even that wouldn't suffice, because trackers have independent snapshot histories of public proofs. And furthermore, snapshot histories are embedded in the Bitcoin blockchain.
Wait, how/where does Bitcoin come into this? Did I miss it somehow? I admit I didn't dive into keybase increadibly deep, but still...
2. It still promotes the closed, walled-gardens. Diaspora or GNU Social support would not be that hard to implement.
Signed proofs could be placed anywhere that's accessible to the API. But that takes coding, and developers have priorities. One can request.
Right.
Anyway, I've created a test identity: https://keybase.io/Proba. Once I've added enough proofs, and have enough trackers, I plan to mess with it by replacing the public key held by Keybase, altering some of the proofs, and so on. Then we can see how that shows up for its trackers, and for other users. I'll also explore impacts of malicious trackers.
Oh, great, I really appreciate that effort. Please keep me posted! -- Pozdrawiam, Michał "rysiek" Woźniak Zmieniam klucz GPG :: http://rys.io/pl/147 GPG Key Transition :: http://rys.io/en/147