Tag Archives: Chaos Calmer

DNSSEC support in OpenWrt 15.05 Chaos Calmer

DNSSEC does not require any special support on the router, since the validation is typically done by the client itself. However, caching the DNSSEC records makes validation for clients faster, and a router in a trusted network can provide DNS replies which carry the ad flag (authenticated data).

Chaos Calmer comes with dnsmasq without DNSSEC validation support by default (DNSSEC is not enabled at compile time). However, one can use the dnsmasq-full package, which provides the DNSSEC features. Without DNSSEC compiled in or enabled, dnsmasq forwards the DNSSEC records properly, however it does not validate them and therefor the DNS replies do not contain the ad flag:

# dig debian.org. SOA +dnssec

; <<>> DiG 9.9.6-P1 <<>> debian.org. SOA +dnssec
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 62577
;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 6, ADDITIONAL: 11
   ^^^^^^^^^^^^^^^ (no ad flag, dnsmasq did not authenticated the DNS response)

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