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The existence of DoH hurts DNSSEC, it doesn't help it. While privacy is the motivating use case for DoH, it's also the case that on-path attackers can't corrupt the results of a DoH query; they have to move upstream of it. The dream of TLSA as a bulwark against suborned CAs has always been problematic, because the security of TLSA records collapses down to that of the TLD operators, the most popular of which are state actors or proxies for them, and most of the remainder are essentially e-commerce firms, not trust anchors. But that doesn't matter, because TLSA as an alternative to the WebPKI is already dead on arrival. So many people have problematic access to DNS that no browser can ship hard-fail DANE; in the (extraordinarily unlikely) future world where mainstream browsers do DANE, everybody will have soft-fail DANE falling back to the WebPKI. So, instead of a small number of (state-run!) PKI roots, you'll have the thousands of legacy operators plus the state-run PKI roots. This problem motivated the design of "stapling" protocols, where we'd basically throw away the DNS part of the protocol, and just keep the TLSA records, and attach them to the TLS handshake. For several years, this was the last best hope for DANE adoption (read Geoff Huston on this, he's a DANE supporter and he's great), and it all fell apart because nobody could get the security model right. It's at this point I like to remind people that the browsers basically had to shake down the CAs to get Certificate Transparency to happen. They held almost all the cards (except for antitrust claims, which were wielded against them) --- "comply with CT, or we'll remove you from our root program". But browsers can't do that with DNS TLD operators; they hold none of the cards. So, in addition to the fact that there's no "DNS Transparency" on the horizon, there's also none of the leverage required to actually get it deployed. DANE does not work. DNSSEC is a dead letter. It's long past time for people to move on. I have a lot of hope for what we can accomplish with ubiquitous DoH-like lookups. |