2 Commits

Author SHA1 Message Date
8a430bf725 feat(prober/osfp): P0fV2Provider + factory dispatch
- decnet/prober/osfp/p0f/provider.py: P0fV2Provider loads the four
  vendored .fp files into per-context signature lists (syn / synack /
  rst / stray) and matches via highest-specificity score across the
  relevant list. Also auto-picks up p0f-decnet.fp if present (GPL-3.0
  additions land there later, empty for now).
- decnet/prober/osfp/factory.py: get_provider / get_all_providers /
  reset_cache, mirrors decnet/geoip/factory exactly. Env-dispatched
  via DECNET_OSFP_PROVIDERS (default "p0f-v2"). Reserved names
  "nmap-osdb" (pending Fyodor's grant) and "decnet-observed" (our
  future curated DB) raise NotImplementedError — visible on the
  factory surface so a typo doesn't silently fall through.
- decnet/prober/osfp/__init__.py now re-exports the public API so
  callers use `from decnet.prober.osfp import get_provider` without
  reaching into submodules (upholds the provider-subpackage rule).

15 new provider+factory tests covering:
- All four DB contexts load (262/61/46/6 sigs per inventory).
- Known-good Linux 2.6 SYN + Linux 2.2 SYN-ACK match end-to-end.
- Unknown observations / contexts return None, not raise.
- Factory memoises, env override honoured, unsupported names raise.
- Reserved names raise NotImplementedError (not silent None).

`sniffer_rollup` wiring lands in the next commit.
2026-04-24 11:50:46 -04:00
620e1f5b1d feat(prober): vendor p0f v2 TCP/IP fingerprint database (LGPL-2.1 → GPLv3 via §3)
Ships the p0f v2.0.8 signature database for passive + active OS
fingerprinting. 375 total signatures across four probe contexts:

- p0f.fp  (262 sigs) — passive SYN fingerprints
- p0fa.fp ( 61 sigs) — SYN-ACK response, for active probes
- p0fr.fp ( 46 sigs) — RST response quirks
- p0fo.fp (  6 sigs) — "stray" packet fingerprints

Replaces reliance on the 10-signature hand-rolled p0f-lite table in
decnet/sniffer/p0f.py for any match job the upstream DB covers.
Keeping the hand-rolled table as a fallback for modern kernels the
v2 DB pre-dates — v2 froze in 2006 so post-Win10 / post-Linux-3.x
kernels won't match against upstream directly. DECNET-authored
additions will go in a sibling p0f-decnet.fp under GPLv3 (not yet
committed; added as the ingester observes real honeypot traffic).

Provenance (full chain in data/README.md):

- Source: Debian snapshot of p0f_2.0.8.orig.tar.gz
- SHA1 matches Debian-recorded 7b4d5b2f24af4b5a299979134bc7f6d7b1eaf875
- Files byte-identical to upstream tarball (verified by hash)

License chain:

- Upstream: LGPL-2.1 (doc/COPYING preserved verbatim as
  data/LICENSE.p0f-upstream, Michal Zalewski's copyright intact).
- DECNET uses the LGPL-2.1 §3 explicit permission to convert to any
  version of the GPL. These files, as consumed in DECNET, are
  effectively GPL-3.0. Chain documented in data/README.md so an
  auditor sees the full reasoning.
- LGPL-2.1 → GPL-3.0 §3 conversion is a settled compat path; same
  mechanism the kernel uses for LGPL userland glue and many other
  projects apply daily.

Rejected path — nmap-os-db under NPSL — because NPSL adds
restrictions GPLv3 §7 prohibits us from accepting. An email is out
to Fyodor requesting an open-source-author exception grant, but we
don't block on it: p0f v2 is a genuine accuracy improvement in
its own right, and adding nmap-osdb later (if granted) plugs into
the same provider interface with zero refactor.

Directory layout mirrors the established provider-subpackage pattern
(see decnet/geoip/, decnet/bus/) per the feedback_provider_
subpackages memory: base + factory + impl/ subpackages, no flat
files. Parser + matcher + factory wiring land in the next commit
sequence.
2026-04-24 11:39:33 -04:00