DNS/実装/KnotDNSresolver/githubについて、ここに記述してください。
https://github.com/CZ-NIC/knot-resolver
lib/validate: scrubbed extra rrs in NS were checked
the validator module should ignore any data that will be scrubbed, that includes non-authoritative data outside current bailiwick. previously, validator attempted to ignore these records only for answer section and had a special case for NS records.
cache: non-authoritative NS records are always unchecked and must be treated as insecure
affected: www.iana.org trying to provide delegation information for CNAME target, which is moot with CNAME target explicit-fetch policy unless the the resolver already knows DNSKEY with which is could verify the records
これか。 ns.icann.org が余計な返事をする。-- ToshinoriMaeno 2016-02-11 10:14:44
$ dig www.iana.org @ns.icann.org.
; <<>> DiG 9.9.5-3ubuntu0.7-Ubuntu <<>> www.iana.org @ns.icann.org. ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 33433 ;; flags: qr aa rd; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 5 ;; WARNING: recursion requested but not available ;; OPT PSEUDOSECTION: ; EDNS: version: 0, flags:; udp: 4096 ;; QUESTION SECTION: ;www.iana.org. IN A ;; ANSWER SECTION: www.iana.org. 3600 IN CNAME ianawww.vip.icann.org. ;; AUTHORITY SECTION: vip.icann.org. 3600 IN NS gtm1.dc.icann.org. vip.icann.org. 3600 IN NS gtm1.lax.icann.org. ;; ADDITIONAL SECTION: gtm1.dc.icann.org. 3600 IN A 192.0.47.252 gtm1.lax.icann.org. 3600 IN A 192.0.32.252 gtm1.dc.icann.org. 3600 IN AAAA 2620:0:2830:296::252 gtm1.lax.icann.org. 3600 IN AAAA 2620:0:2d0:296::252 ;; Query time: 175 msec ;; SERVER: 199.4.138.53#53(199.4.138.53) ;; WHEN: Thu Feb 11 19:12:12 JST 2016 ;; MSG SIZE rcvd: 206
こっちに訊くと上に記述のような返事はないが。
$ dig www.iana.org @a.iana-servers.net.
; <<>> DiG 9.9.5-3ubuntu0.7-Ubuntu <<>> www.iana.org @a.iana-servers.net. ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 17725 ;; flags: qr aa rd; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1 ;; WARNING: recursion requested but not available ;; OPT PSEUDOSECTION: ; EDNS: version: 0, flags:; udp: 4096 ;; QUESTION SECTION: ;www.iana.org. IN A ;; ANSWER SECTION: www.iana.org. 3600 IN CNAME ianawww.vip.icann.org. ;; Query time: 71 msec ;; SERVER: 199.43.132.53#53(199.43.132.53) ;; WHEN: Thu Feb 11 19:10:25 JST 2016 ;; MSG SIZE rcvd: 73
Unboundの出力はこんな感じだが。
$ dig www.iana.org ; <<>> DiG 9.9.5-3ubuntu0.7-Ubuntu <<>> www.iana.org ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 45104 ;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 1 ;; OPT PSEUDOSECTION: ; EDNS: version: 0, flags:; udp: 1220 ;; QUESTION SECTION: ;www.iana.org. IN A ;; ANSWER SECTION: www.iana.org. 3600 IN CNAME ianawww.vip.icann.org. ianawww.vip.icann.org. 120 IN A 192.0.32.8 ;; Query time: 745 msec ;; SERVER: 127.0.0.2#53(127.0.0.2) ;; WHEN: Thu Feb 11 19:07:57 JST 2016 ;; MSG SIZE rcvd: 89