Tools like fpdns send OPCODE=IQUERY/STATUS/NOTIFY/UPDATE or set the reserved
Z bit to fingerprint resolver behaviour. Previously all these were parsed as
standard queries with no signal.
- opcode!=0 → fingerprint_probe probe=opcode_<name>, NOTIMP response;
fired before qdcount check so qdcount=0 UPDATE packets are still caught.
- Z bit set OR (AD+CD without RD) → fingerprint_probe probe=header_flags;
AD alone with RD is ignored to avoid tagging DNSSEC-aware stubs.
- Both variants contribute to recon_burst.
qclass=255 in a standard query is unusual enough to be a fingerprinting probe
(fpdns, various scanner scripts). Previously it was logged as a plain query
with qclass=ANY in the event field; now it emits fingerprint_probe with
probe=qclass_any and returns REFUSED — consistent with how we treat other
probe types. Contributes to recon_burst.
The inline probe_map dict inside _handle made tests blind to the probe
catalogue and couldn't be extended without touching the hot path. It is now
module-level _CHAOS_PROBE_MAP. authors.bind. joins the three existing entries
so it gets named correctly instead of carrying the raw qname.
Packets with multiple questions were silently parsed at q0 only; the extra
questions were invisible. Now emits multi_question at severity=5 with the
qdcount and q0 qname, then falls through and answers q0 normally.
Silent drops on <12B packets, qdcount=0, and question-section ValueError gave
fuzzers and scanners a completely dark target. New events malformed_packet,
empty_question_section, and question_parse_error fire at severity=5 so these
probes are visible without counting toward recon_burst.
Adds DNS_FORWARD_BUDGET (default 50) and DNS_FORWARD_WINDOW (default 1.0s)
env vars. _can_forward() maintains a rolling deque of upstream call
timestamps; queries that exceed the budget within the window are answered
with the sinkhole (127.x) instead of being forwarded, making the honeypot
ineligible as a sustained amp vector even when real_recursive is enabled.
Rate limit is global (not per-source) so IP-spoofed amplification floods
hit the ceiling regardless of how many source addresses are rotated.
When DNS_REAL_RECURSIVE=true and DNS_ZONE_MODE=recursive, out-of-zone
queries are forwarded to DNS_UPSTREAM (default 8.8.8.8:53) via async
UDP. Upstream response is relayed as-is; on timeout or error the
already-computed sinkhole (127.x) is returned instead.
_handle() always runs first so logging, tunneling detection, flood
tracking, and recon-burst aggregation fire on every query regardless
of whether the response ultimately comes from upstream. _dispatch()
overlays forwarding on top of the sync handler.
Protocol handlers (UDP datagram_received, TCP session) are now async
via asyncio.ensure_future / await _dispatch(). Service class exposes
real_recursive (bool) and upstream (string) config fields.
RA=1 + empty answer section is immediately detectable as fake by any
open-resolver scanner. Recursive mode now behaves like open mode
(127.0.0.x sinkhole, deterministic on qname) with RA=1 and AA=0,
matching what a real recursive resolver returns.
- Add per-src QPS counter (_qps_window) with flood_suspect event at ≥50 qps/10s;
one event per src per 30s cooldown, does not suppress baseline query events.
- Add tracking_evicted telemetry every 100 LRU evictions so IP-rotation evasion
of _txt_times/_qps_window/_recon_window is observable, not silent.
- Shared _track_lru helper consolidates LRU touch + eviction signalling across
all three bounded OrderedDicts.
- Add TYPE_AAAA=28 support: _fake_ipv6() returns deterministic ULA (fd::/8)
addresses for in-zone names; extra_records parser now accepts and validates
AAAA entries via socket.inet_pton.
- Add per-src recon-burst aggregation (_recon_window): fingerprint_probe +
zone_transfer + amp_probe are tracked per source in a 60s window; recon_burst
fires when ≥2 distinct signal types seen, once per src per 120s cooldown.
- 47 tests passing (19 new across TestAAAARecords, TestFloodDetection, TestReconBurst).
Python asyncio DNS server on UDP+TCP/53 masquerading as BIND 9.x.
Emits four event_type values: query, fingerprint_probe (version.bind /
hostname.bind / id.server CHAOS), zone_transfer (AXFR/IXFR, always
REFUSED), amp_probe (qtype=ANY or EDNS udp_size>1232), and
tunneling_suspect (long high-entropy labels or rapid TXT burst).
Zone persona is generated per-decky from instance_seed (domain name,
SOA serial, NS, A, MX, TXT SPF); overridable via config_schema.
Three zone modes: auth (default), recursive, open (sinkhole).
