feat: hostname resolution via reverse DNS and passive OS inference from banners - #42
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…om banners Closes #37 Two enrichment steps added after nmap in orchestrate_scan(): ## Hostname (dns_lookup.py) - resolve_hostnames() performs socket.gethostbyaddr() for any host nmap did not name (no PTR in XML) - Per-IP SIGALRM timeout (1s) prevents a slow resolver stalling scans - Fails gracefully — missing PTR leaves hostname as empty string ## OS hints (os_inference.py) - enrich_os_guesses() infers os_guess from service/version banners for any host where os_guess is still empty after nmap - SSH banner patterns: Ubuntu, Debian, Raspbian, FreeBSD, Windows, etc. - HTTP Server header patterns: OpenWrt, DD-WRT, Synology DSM, QNAP, etc. - Service-name fallbacks: microsoft-ds/msrpc/RDP → Windows ## Tests (test_enrichment.py) — 21 unit tests - OS inference: 12 tests covering SSH banners, HTTP headers, service-name hints, priority ordering, no-match case - Hostname: 6 tests covering PTR resolution, existing-name guard, OSError/TimeoutError graceful handling, selective querying Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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Closes #37
Changes
backend/app/scanner/dns_lookup.py(new)Reverse DNS fallback for hosts nmap couldn't name. Uses
socket.gethostbyaddr()with a per-IP SIGALRM timeout (1 s) to avoid stalling the scan on unresponsive resolvers.backend/app/scanner/os_inference.py(new)Passive OS inference from service/version banners — no elevated privileges required. Recognises:
microsoft-ds,msrpc,ms-wbt-server→ Windowsbackend/app/scanner/__init__.pyTwo new steps wired into
orchestrate_scan()after nmap completes:resolve_hostnames()— fills missing hostnamesenrich_os_guesses()— fills missing os_guessbackend/tests/test_enrichment.py(new — 21 unit tests)Full coverage of both modules: banner matching, priority ordering, graceful failure, no-overwrite guard.