[lol768]

The ship has very much sailed now with ballot SC63, and this is the result, but I still don't think CRLs are remotely a perfect solution (nor do I think OCSP was unfixable). You run into so many problems with the size of them, the updates not propagating immediately etc. It's just an ugly solution to the problem, that you then have to introduce further hacks (Bloom filters) atop of it all to make the whole mess work. I'm glad that Mozilla have done lots of work in this area with CRLite, but it does all feel like a bodge.

The advantages of OCSP were that you got a real-time understanding of the status of a certificate and you had no need to download large CRLs which become stale very quickly. If you set security.ocsp.require in the browser appropriately then you didn't have any risk of the browser failing open, either. I did that in the browser I was daily-driving for years and can count on one hand the number of times I ran into OCSP responder outages.

The privacy concerns could have been solved through adoption of Must-Staple, and you could then operate the OCSP responders purely for web-servers and folks doing research.

And let's not pretend users aren't already sending all the hostnames they are visiting to their selected DNS server. Why is that somehow okay, but OCSP not?

[ekr____]

The problem with requiring OCSP stapling is that it's not practically enforceable without breakage.

The underlying dynamics of any change to the Web ecosystem is that it has to be incrementally deployable, in the sense that when element A changes it doesn't experience breakage with the existing ecosystem. At present, approximately no Web servers do OCSP stapling, so any browser which requires it will just not work. In the past, when browsers want to make changes like this, they have had to give years of warning and then they can only actually make the change once nearly the entire ecosystem has switched and so you have minimal breakage. This is a huge effort an only worth doing when you have a real problem.

As a reference point, it took something like 7 years to disable SHA-1 in browsers [0], and that was an easier problem because (1) CAs were already transitioning (2) it didn't require any change to the servers, unlike OCSP stapling which requires them to regularly fetch OCSP responses [1] and (3) there was a clear security reason to make the change. By contrast, with Firefox's introduction of CRLite, all the major browsers now have some central revocation system, which works today as opposed to years from now and doesn't require any change to the servers.

[0] https://security.googleblog.com/2014/09/gradually-sunsetting... [1] As an aside it's not clear that OCSP stapling is better than short-lived certs.

[lol768]

I think you are correct. There were similar issues with Firefox rolling out SameSite=Lax by default, and I think those plans are now indefinitely on hold as a result of the breakage it caused. It's a hard problem to solve.

> As an aside it's not clear that OCSP stapling is better than short-lived certs.

I agree this should be the end goal, really.

[dlenski]

> The underlying dynamics of any change to the Web ecosystem is that it has to be incrementally deployable, in the sense that when element A changes it doesn't experience breakage with the existing ecosystem.

Absolutely, this is important.

But I don't understand why this should have any effect on OCSP-stapling vs. CRL.

As you note, "approximately no Web servers do OCSP stapling, so any browser which requires it will just not work." But browsers also cannot rely on CRLs being 100% available and up-to-date.

Enforcing OCSP stapling and enforcing a check against an up-to-date CRL would both require this kind of incremental or iterative deployment.

> As an aside it's not clear that OCSP stapling is better than short-lived certs.

This is equally applicable to CRL, though.

The current plan for phased reduction of TLS cert lifespan is to stabilize at 47 days in 2029. If reducing cert lifetime achieves the goal of reducing the value of compromised certs, then any mechanism for revoking/invalidating certificates will be reduced in value.

[woodruffw]

> Why is that somehow okay, but OCSP not?

I think the argument isn’t that it’s okay, but that one bad thing doesn’t mean we should do two bad things. Just because my DNS provider can see my domain requests doesn’t mean I also want arbitrary CAs on the Internet to also see them.

[dogma1138]

I never understood why they didn’t tried to push OSCP into DNS.

You have to trust the DNS server more than you trust the server you are reaching out to as the DNS server can direct you anywhere as well as see everything you are trying to access anyhow.

[dadrian]

OCSP stapling, when done correctly with fallback issuance, is just a worse solution than short-lived certificates. OCSP lifetimes are 10 days. I wrote about this some here [1].

[1]: https://dadrian.io/blog/posts/revocation-aint-no-thang/

[PunchyHamster]

It's funny that putting some random records in DNS is enough to have enough "ownership" to make a cert for one but we can't use same method for publishing revoking

[ocdtrekkie]

The entire existence of CAs is a pointless and mystical venture to ensure centralized control of the Internet that, since now entirely domain-validated, provides absolutely no security benefits over DNS. If your domain register/name server provider is compromised, CAs are already a lost cause.

[gerdesj]

"And let's not pretend users aren't already sending all the hostnames they are visiting to their selected DNS server. Why is that somehow okay, but OCSP not?"

Running your own DNS server is rather easier than messing with OCSP. You do at least have a choice, even if it is bloody complicated.

SSL certs (and I refuse to call them TLS) will soon have a required lifetime of forty something days. OCSP and the rest becomes moot.

[dogma1138]

You still are reaching out to authoritative servers for that domain so someone else other than the destination knows what you are looking for.

The 47 day life expectancy isn’t going to come until 2029 and it might get pushed.

Also 47 days is still too long if certificates are compromised.

[dlenski]

> I still don't think CRLs are remotely a perfect solution (nor do I think OCSP was unfixable)

> The privacy concerns could have been solved through adoption of Must-Staple

Agreed. I haven't followed every bit of the play-by-play here, but OCSP (multi-)stapling appeared to me to be a good solution to both the end-user privacy concerns and to the performance concerns.