In the long run, fixing bugs is almost always better than working around them. DNSSEC is a bug. So are CAs. We can and should fix both.
He is not arguing that DNS security cannot or should not be improved; in fact, he explicitly states the exact opposite.
It's going to settle into general usability at just about the time cryptographers deprecate ECC entirely!
"As a rule, strong feelings about issues do not emerge from deep understanding."
And if we have a secure DNS, then CAs are completely redundant. I'd much rather trust a handful of domain registrars than a handful of domain registrars, plus 100 random questionably competent organisations all over the world. Especially when any one of them can generate keys for every domain on the planet.
A confidential DNS has real value. Without it, ISPs actively monitor customers and sell analytics about usage upstream; there are other problems, but virtually every US user faces that one. It's hard to imagine wanting to trade confidentiality off.
A high-integrity DNS is a more dubious proposition. You'd obviously rather have integrity than not, ceteris paribus, but we have effective mitigating controls for DNS forgery, so you might imagine trading it off.
Availability also sounds like a no-brainer, until you remember that almost every other component of the networking stack also has availability issues. You might not want to trade anything at all to get a more highly-available DNS, if you're going to be just as susceptible to DOS attacks because the current DDoS meta is application-layer anyways.
There are a bunch of different approaches to securing the DNS, and they make different tradeoffs.
DoH focuses on confidentiality, and has bank-shot benefits to integrity (because it breaks forgery attacks from on-path attackers). Confidentiality is its primary purpose and it trades basically everything else off.
DNSSEC makes the opposite tradeoffs: it's exclusively for integrity, provides no confidentiality, and highly prioritizes availability (that's why it has elaborate authenticated denial systems).
Depending on what you want to achieve, "secure" DNS can make sense and actually get deployed and used, as DoH is, or it can make almost no sense and see almost no uptake.
Which might still be better, if only because it limits the surface area.
shudders
(1) We're also rearchitect the way all DNS is done so that every lookup from every phone and laptop is fully recursive, so that everyone validates DNSSEC chains instead of relying on the AD bit that cable company DPI devices switch off.
(2) People will lose all attachment to their current domain names and simply migrate to TLDs that have policies they agree with, rather than .COM and .IO, which are under the demonstrated de facto control of the NATO IC.
There's no such thing as a "trust store" in practice. To be "trusted" you just need to demonstrate you have control over a DNS TXT record, and we don't need a special "store" or intermediary for that.
Certificate authorities are an artifact of a bygone time and an entirely different model of internet infrastructure.
(Moving the PKI into DNS does not remove it, it just moves it around.)
Better in DNS though. You could have certs mirror the structure of DNS. Install a single root signing key for the top level DNS registry on client devices. Then you can query that to find out the signing keys for .com, .net, .au, etc. And continue from there.
One big problem with the CA system is that any CA - even the most incompetent - can sign certificates for any domain. If trust was moved to DNS, there would only be a single organisation that could forge certificates for any given domain. Using 7 as a private key? What a joke. The CAs aren't worthy of trust.
We already have to trust the domain name registrars anyway, since CAs query them to figure out if you own a domain before signing a certificate. In total, removing CAs would not only simplify the system. But it would allow scoped signatures. And we'd end up needing to trust far fewer actors to have a secure internet.
Is this not what CAA records were intended to solve? It seems like in practice they're only used by CAs to decide if they can sign a cert for a given domain, but it seems like a client could use it to determine if a server cert was from the correct CA.
1. A domain would have to keep the CAA records for a CA in place to keep using the certificates from that CA, but that means continuing to authorise new issuance too. Right now, I can remove the `letsencrypt.org` value to stop them from issuing new certificates for me, but I can keep using any certificates I have until they expire.
2. The client would need to have support for this new DNS RR type.
3. The client would need a secure way to query DNS, which is not widespread.
I infer from the wording around there and elsewhere in the RFC that this is mostly because someone could switch issuers but still serve valid certs from the prior issuer, and there's no way an RP would have a historical record of which CAA values were in effect when to be able to determine if the issuance was valid or not.
I think the idea that CAs are uniquely incompetent is probably incorrect.
(Half joking).
The dependency of "accetpable", i.e., not self-signed, TLS certificates on DNS, i.e., a domain name in a TLD created by "ICANN", is funny when one considers that the traffic to authoritative nameservers is still unencrypted. It stands to reason that DoH and other "accepted" forms of "DNS security" are only to stop ISPs from stealing Silicon Valley's surveillance advertising racket. Neither is "DNSSEC" providing the user with any real "security"; it's protecting a monopoly. The "security" is against anyone who might try to use domains names not blessed by "ICANN"
Indeed there's no need for CAs just as there is no need for ICANN