Hand-rolled RFC 5389/5780 STUN client (stdlib only) that exercises the
server's stun-5780 capability: one socket, three binding requests
(primary, OTHER-ADDRESS alternate IP, CHANGE-REQUEST port) — the
comparison classifies NAT mapping and filtering behavior.
Verified on the OnePlus: local 10.13.102.124 -> mapped
178.191.120.247:53259 (behind_nat true), alternate address answered from
the server's second IP, mapping endpoint-independent, filtering
address/port-dependent. Finding nat.symmetric (medium) for the
P2P-hostile case.
Two real bugs found by running it: port preservation was misread as "no
NAT" (compare addresses, not ports), and an unbound socket reports the
wildcard local address (resolve via a throwaway connected socket).
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Resolves the server's canary zone through the platform resolver and
compares against the spec-frozen ground truth (probe-protocol §6.1):
reference records detect answers rewritten in flight, and a per-run nonce
name (uncacheable) proves the query reached the authoritative server.
Findings: dns.answer_rewritten (high), dns.authoritative_unreachable
(medium).
Verified on the OnePlus against the deployed fmr zone: 4/4 reference
records matched exactly, nonce name answered 192.0.2.21 with
reached_authoritative=true. First full client<->server measurement loop
on real hardware; report archived.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Mirrors NetworkMonitor: per active network, fetch the AOSP default
generate_204 endpoints and check for HTTP 204 No Content.
- HTTPS https://www.google.com/generate_204 == 204 -> validated internet
- HTTP http://connectivitycheck.gstatic.com/generate_204: 204 -> clean;
an unfollowed 3xx or a 200-with-body -> captive portal (Location captured)
- both fail -> no_internet
Per-network verdicts (bound via Network.openConnection), redirects not
followed (the 3xx IS the evidence). Findings: captive_portal (medium) and
no_internet (high). New test type net.captive_portal (net family ->
connectivity category). App gains usesCleartextTraffic (a network
diagnostic that intentionally probes plain HTTP).
Builds; measurement verdict tests still green. On-device verification
deferred with the rest (flaky test devices).
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
First assembling build of the production app. Android toolchain mirrors
the prober (AGP 9 built-in Kotlin; applying kotlin.android too
double-registers the kotlin extension — the one gotcha).
core-probe (Android lib): Probe→core-measurement Test abstraction;
NetworkInventory (LinkProperties→networks[]), LinkSnapshotProbe,
per-network IcmpProbe (ported from the prober's validated logic).
app (Compose): RunViewModel orchestrates probes into a MeasurementDocument
with a §7.3 summary + first-pass findings; UI renders traffic lights,
networks, tests, findings; JSON export. Rotation-safe (ViewModel).
App-tier only; server-facing (core-engine) + Shizuku are additive
follow-ups. Debug APK 9.5 MB, assembles clean.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
