The miekg/dns zone parser preserves whichever text form the input
used for an escaped byte. RFC 1035 §5.1 lets the same byte appear
as \DDD (decimal) or \c (literal character), so a zone file
written with has\046dot.campus.edu. is stored under that literal
string. Incoming queries, by contrast, arrive on the wire and are
unpacked by miekg/dns into the canonical form has\.dot.campus.edu.
The two strings don't compare equal in the tree, so the record is
silently unreachable.
Pack-then-unpack the owner name on Insert so the stored key uses
the same canonical form as anything that comes off the wire. Only
runs when the name contains a backslash, so the common case is a
no-op string compare.
Fixes#8012
Signed-off-by: Charlie Tonneslan <cst0520@gmail.com>
f4f767fb4e