Comment by tptacek
16 hours ago
DANE replaces this system with one that has the same basic cryptographic properties, but in which you can't eject bad actors --- or even monitor them with a mandatory transparency log. It's strictly worse than this.
16 hours ago
DANE replaces this system with one that has the same basic cryptographic properties, but in which you can't eject bad actors --- or even monitor them with a mandatory transparency log. It's strictly worse than this.
WebPKI can't eject the bad actors that would cause trouble in DANE either. If your TLD conspires against you, they can certainly establish domain control and get a properly issued WebPKI cert.
Visibility through Certificate Transparency logs would at least make it a matter of record that it occurred, though.
The WebPKI semi-routinely kills certificate authorities. The point is that you can't kill a TLD operator.
> The point is that you can't kill a TLD operator.
I agree, you can't kill a TLD operator. But WebPKI relies on TLD operators to establish identity, so I don't see what we gain from WebPKI, other than mandatory CT logs, and not having to faff about with DNSSEC :P ... both of those are pretty valuable, of course.
I'll put it another way: why do we want a CA to tell us that someone controls a domain, when the TLD could tell us? The TLD is authoritative with regard to who controls a domain; CAs can only report on what they have observed.
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> It's strictly worse than this.
Maybe if people implemented name constraints and the CA/B forced CAs to use them. But not as it is; unconstrained sub-CAs are a scourge on the Web PKI.
Name constraints are intended for organizations which want to issue publicly-trusted certificates for their own domains. Name constraints are already widely supported and name constrained sub-CAs exist for this purpose in the WebPKI.
eMudhra is not such a case. They are a root CA that issues certificates to the general public all over the world. In fact, they are now the preferred vendor for numerous US universities via InCommon[1]. There is no way to meaningfully name constrain them.
[1] https://incommon.org/certificates
Can you share any insight about how an Indian CA became the preferred vendor for US universities despite the existence of LetsEncrypt? I know this is kind of a dumb question.
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I like constraints too, but listen carefully to EKR and 'agwa on this, because a lot of things that seem like straightforward fixes are much more complicated in reality. The most important thing I want from the WebPKI is expensive entry and the death penalty for fuckups, and I think we basically have that now.
It has the property of aligning cryptographic authentication with the domain name hierarchy. Yes, you trust the hierarchy. You trust LE too, so what? We need to move away from any authority being able to authenticate anyone, and DNS naturally aligns with the goal.
You've been vocal for a long time against DNSSEC deployment too for no discernable reason.
Why are you against every single thing that tries to make DNS useful for securing anything?
DNSSEC creates more operational issues than it solves. It's easy to screw up, which means your domain completely stops resolving when that inevitably occurs. None of the FAANGs use it for their main web sites, so what does that tell you?
It can also be disabled at the whim of anyone operating a resolver, as was seen with Cloudflare during the .de TLD DNSSEC snafu back in May.
Do the words "no discernible reason" just mean something very different to you than they do to me? Because I've written somewhere in the vicinity of 100,000 words about the problems of DNSSEC over the last 20 years. My written DNSSEC critique predates HN itself.
This particular issue has nothing to do with "aligning authentication with the name hierarchy". The exact same thing that happened to EMudhra could happen to any TLD operator. The difference is that we have essentially no recourse when that happens, and far less ability to detect malfeasance.
Low TTLs aren’t incompatible with the ideal of using DNSSEC though? From what I can tell DS records typically have TTL of 1 day in the root domain.
What is a difference, versus DANE, is that TLS uses CT. Compromised TLDs happened recently but was found out through CT. A compromised TLD still kills the whole system for a time regardless.
I think DNSSEC still has some use in enforcing email TLS and for CAs.
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