At any point in history, have CAs revoked certs solely to censor a target website?
Maybe the answer is yes. I don't know. But this is a rude wake-up call for me and everyone else who tried to force the world into this shape.
We've all been shouting "You have to use TLS! It's fundamental security 101. If you're not using https, your site is probably broken. And there's no reason not to do it, since it's so easy."
Surprise: Now nobdoy trusts http, and those that control https can revoke their trust based on arbitrary human morals rather than solid technical reasons.
I was a pentester for years and not once did anybody mention this threat anywhere. It's blindingly obvious in hindsight, but it was too easy not to think about it.
Let's Encrypt is in the exact same position. Why do we trust them? Think about it -- they're under US jurisdiction and subject to US laws. The government could compel them to revoke certs.
We're lucky that it's just a minor annoyance. Picture a world where no major browser renders http at all, and the only way to get a site online is to have a trusted cert.
This is not far from reality: If the Magic Leap turns out not to be vaporware, they're going to be launching a DRM-powered internet that can't be adblocked. And that means we'll all be subject to government whims far more than we'd like to admit.
Really the issue is that decentralization isn't very compatible with convenience and people generally place a lot more value on convenience than things like Sci-Hub.
So it's not technically infeasible to have networking gear drop any connection which doesn't chain back to a government-approved root?
Yse, and that is a very scary thought. China is doing something similar already.
Only on old TLS versions. TLS 1.3 changed it so the server certificate is also encrypted.
Whether the traffic is authenticated or not, ISPs block sites when instructed by government orders. And that is much harder to work around than a revoked TLS cert (although a revoked cert does mean "totally blocked" for almost all users).
These are not purely technical challenges, but rather political issues that must be addressed as such. We will always lose to our governments if we focus only on technical solutions to censorship.
I'd like to add that the USA government, for the most part, does not accept an absolute right to private communication. The possibility of ubiquitous end-to-end encrypted communications with tools like TLS and WhatsApp is not something we should take for granted. The USA matters here because we are the powerful nation with the strongest legal and cultural commitment to freedom of speech.
Revoking certs from US CAs is probably the new DNS seizure, post- encryption and TLD expansion.
Although hopefully it'll die a quick death when they realize it's ineffective.
SEC takedowns have happened for years without relying on TLS.
For instance, I recently consolidated my personal projects and site onto one server. I needed a single certificate that'd cover two domains. Digicert combined two of my orders into one certificate with two wildcard SANs. You wouldn't be able to do that with LE.
Edit: I was under the impression you couldn't do multiple wildcard SANs in LE but according to some forum posts it's fully possible as long as validation passes.
Sharing a (wildcard) certificate between multiple servers.
LE are a US corp, subject to US laws, and at the whim of US court orders. The implications of that are worth gaming out.
Our laws are (arguably) mostly fair. But there are cases where they're not.
Picture a world where an administration rises to power in the US on a platform that seems insane, but everybody endorses it anyway. And this platform just so happens to be against the sort of thing you're trying to do on the internet.
Sci-hub are stealing. We as a community are mostly fine with that. We don't consider it stealing, because the moral good outweighs the bad by a hundred to one.
But this isn't about Sci-hub. This is about a world in which we're free to do as we please, because we have the ability to decide what we want to do. If we want to make a site that can make information available, and someone else doesn't like that information or feels that they own it, what do you do? You have no power.
And when you blindly put your faith in institutions like Let's Encrypt on their platform of openness and trust, you set yourself up for a shift: One day you wake up and find out you were mistaken, and we were all mistaken to push this centralized model in the name of security and convenience.
And of course, that's the fundamental truth, isn't it? Liberties have always been eroded by pushing security and convenience.
We should think carefully about who we trust, and why.
That's precisely the main concern here, given the nature of SciHub.