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A name lookup passing through systemd-resolved's stub listener into a cache, a validator and an encrypted transport, with the validator and the encryption switched off

Resolved: The Resolver You Are Already Running

systemd-resolved is running on most Linux desktops right now, caching every lookup and validating none of them. This walks the resolution path from nss-resolve to the two stub listeners, measures what the cache is worth on a real machine, turns DNSSEC on and shows the three verdicts it can return, and explains why validation is off by default when upstream ships it on. Then a census of how little of the web is actually signed, DNS over TLS and its strict-versus-opportunistic trap, and the DNS over HTTPS support that has been requested since 2018 and still does not exist. Ends with what Fedora, Ubuntu, Debian and the RHEL family each ship, how to wire it into each one, and why the features your distro disabled are defaults rather than missing code.

27th September 2026 Â· 38 min Â· 8443 words Â· Damien Dye

DNS Over HTTPS Walks Straight Past Your Controls

DNS over HTTPS encrypts your lookups, which is good, and sends them to a resolver of the client’s choosing on port 443, which is the problem. Your own resolver never sees the query, so the blocklist it would have failed, the threat feed it would have hit and the log line it would have written all vanish. This post walks the mechanism: why one encrypted web connection among thousands is invisible at the border, who on a machine can pick a resolver you never chose (the OS, the browser, any app, any script on any web page, and malware), and the documented cases, from a page’s own JavaScript querying a public DoH endpoint that allows cross-origin requests, to Godlua and PsiXBot hiding their command channel inside DoH, to the OilRig APT exfiltrating data over it. Then the case that the privacy story is a cover: DNS over TLS already encrypted DNS in 2016, on a port the network operator can still govern, so the only thing DoH adds over it is defeating the admin, which is why the browser vendors who wrote and shipped it, and the advertising firm that runs the biggest public DoH resolver, are the ones who gained. Then the fix, which is not to ban encryption. Run your own DoH and DoT resolver, advertise it with Discovery of Designated Resolvers, refuse port 53, port 853 and known public DoH resolvers at the border, and answer the Firefox canary so the browser stands down. Keep the encryption. Take back who chooses the resolver. It closes on the fallout: the same DNS-based enforcement runs across Europe and in Australia, and courts in Italy, France, Belgium and Germany are now ordering the public resolvers themselves to block, with Cloudflare fined and appealing, Google refusing in silence and OpenDNS switching itself off for whole countries. The pattern underneath is a US design imposed on the world, and a US government that casts other countries’ laws as extortion of American firms and warns them not to comply.

24th September 2026 Â· 38 min Â· 9567 words Â· Damien Dye