resolver: ask a referral's nameservers that come without addresses (closes #221)

Looking up a nameserver's own address followed only the addresses a referral gave, so a nameserver whose zone is delegated without them, such as a.ntpns.org of pool.ntp.org, never resolved. The walk to a name's nameservers looked addresses up only when a referral gave none. Both now go through queryZone, which asks the nameservers whose addresses the referral gives first and, if none of them gives a usable reply, looks up and asks the others. maxLookupDepth stops lookups three deep, so delegations that point at each other still end; when the limit is why no address was found, the error is ErrLookupDepthExceeded, not "no address". Model: opus-5-5
2026-10-02 10:12:08 +02:00
parent e46db71821
commit 008ec5d13a
6 changed files with 300 additions and 46 deletions
@@ -19,6 +19,8 @@ trial run of the finished image: https://git.eeqj.de/sneak/dnswatcher/issues/149

 # Completed Steps

+- 2026-10-02: nameservers a referral names without addresses are looked up,
+  three deep at most; `pool.ntp.org`'s nameservers resolve (closes #221).
 - 2026-10-02: an apex domain is not counted or listed as a hostname; its records
  show under Domains, and notifications about them say `Domain:` (closes #224).
 - 2026-10-02: the dashboard lists each nameserver's record types in one fixed