DNS/qname-minimisation/検索例/unboundについて、ここに記述してください。

../kresd でのlogもある。

一段ずつ追いかけている。/2

$ dig -t txt u.v.w.x.y.z.s1.brau.jp @127.0.0.3

; <<>> DiG 9.12.3 <<>> -t txt u.v.w.x.y.z.s1.brau.jp @127.0.0.3
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 54544
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 2, ADDITIONAL: 2

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1220
;; QUESTION SECTION:
;u.v.w.x.y.z.s1.brau.jp.                IN      TXT

;; AUTHORITY SECTION:
s1.brau.jp.             2560    IN      SOA     a.ns.brau.jp. hostmaster.s1.brau.jp. 1546586853 16384 2048 1048576 2560
s1.brau.jp.             600     IN      NS      a.ns.brau.jp.

;; ADDITIONAL SECTION:
a.ns.brau.jp.           3600    IN      A       14.192.44.29

;; Query time: 99 msec
;; SERVER: 127.0.0.3#53(127.0.0.3)
;; WHEN: 金  1月 04 16:32:29 JST 2019
;; MSG SIZE  rcvd: 133

@400000005c2f0c172874124c 276e870c:605d:5a7a + S0001 s1.brau.jp
@400000005c2f0c1728ccf434 276e870c:d67b:a62f + S0002 brau.jp
@400000005c2f0c1728d41084 276e870c:63be:adb0 + S0001 ns.brau.jp
@400000005c2f0c1729159dc4 276e870c:b256:df94 + S0001 z.s1.brau.jp
@400000005c2f0c1729cd8f9c 276e870c:cf32:7645 + S0001 a.ns.brau.jp
@400000005c2f0c1729d7633c 276e870c:9e1f:f143 + S0001 y.z.s1.brau.jp
@400000005c2f0c172a799e7c 276e870c:6eda:691a + S0001 x.y.z.s1.brau.jp
@400000005c2f0c172b1bed44 276e870c:8cbd:3ff5 + S0001 w.x.y.z.s1.brau.jp
@400000005c2f0c172bb9e2c4 276e870c:833d:3f54 + S0001 v.w.x.y.z.s1.brau.jp
@400000005c2f0c172c560b54 276e870c:8377:058e + S0001 u.v.w.x.y.z.s1.brau.jp
@400000005c2f0c172cf646dc 276e870c:7aad:1a79 + S0010 u.v.w.x.y.z.s1.brau.jp

1. Unbound / iterator.c

if(iq->minimisation_state != DONOT_MINIMISE_STATE
                        && !(iq->chase_flags & BIT_RD)) {
                        if(FLAGS_GET_RCODE(iq->response->rep->flags) !=
                                LDNS_RCODE_NOERROR) {
                                if(qstate->env->cfg->qname_minimisation_strict)
                                        return final_state(iq);
                                /* Best effort qname-minimisation.
                                 * Stop minimising and send full query when
                                 * RCODE is not NOERROR. */
                                iq->minimisation_state = DONOT_MINIMISE_STATE;
                        }
                        if(FLAGS_GET_RCODE(iq->response->rep->flags) ==
                                LDNS_RCODE_NXDOMAIN) {
                                /* Stop resolving when NXDOMAIN is DNSSEC
                                 * signed. Based on assumption that nameservers
                                 * serving signed zones do not return NXDOMAIN
                                 * for empty-non-terminals. */
                                if(iq->dnssec_expected)
                                        return final_state(iq);
                                /* Make subrequest to validate intermediate
                                 * NXDOMAIN if harden-below-nxdomain is
                                 * enabled. */
                                if(qstate->env->cfg->harden_below_nxdomain) {

2. minimisation 時

LDNS_RR_TYPE_A でqueryを送っている。 

-- ToshinoriMaeno 2019-01-04 15:09:37

ここは素直にSOAを問い合わせるのがいいのではないか。