mrambossekandClaude Opus 5
a17c3fd9e6
A tablet on a healthy network could not resolve anything. The DNS server answered the bare name correctly — NOERROR, two records, A and AAAA, with and without EDNS0 — so the earlier finding blamed the device's resolver. It was wrong. The network advertised hudelist.local as a search domain and the server silently dropped every query under it: not NXDOMAIN, nothing at all. Resolvers append search domains, so they waited for a reply that was never coming. Silence is the part that makes this vicious. A negative answer moves a resolver on; no answer looks like packet loss, so it retries, and some give up on the lookup entirely. It also explains how two devices on one network can disagree about whether DNS works — the phone tried the plain name first and never noticed. The probe now asks about a nonce name under each advertised search domain, where the wanted answer is NXDOMAIN and only silence is a fault. The finding is ordered ahead of dns.system_resolver_broken so the two cannot both fire: without that, this exact network gets told its device is broken. Severity follows the harm rather than the shape. HIGH when resolution is actually failing, MEDIUM when the domain is a black hole but this resolver happens to try the plain name first — calling that HIGH would be crying wolf on a network that works. The message names the fix and notes that .local is reserved for mDNS by RFC 6762 and widely dropped by design, while home.arpa (RFC 8375) is the name reserved for this. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Echolot app
The production Android client (spec). Native Kotlin + Jetpack Compose. Multi-module; built bottom-up from a verifiable protocol spine.
Modules
| Module | Type | Status |
|---|---|---|
core-protocol |
pure Kotlin/JVM | done — client half of probe-protocol.md, verified live against the server |
core-measurement |
pure Kotlin/JVM | planned — measurement-schema.md types |
core-probe |
Android lib | planned — app-tier probes, ported from echolot-prober |
core-shizuku |
Android lib | planned — dual-path executor (UserService + newProcess fallback) |
app |
Android app | planned — Compose UI |
core-protocol is deliberately Android-free so it builds and unit-tests on any JDK (no Android
SDK) and can run integration tests against a live server.
core-protocol
Implements the control plane (SPKI-pinned enrollment/profile/sessions via HttpsURLConnection —
Android-API-1 compatible, hostname verification off because trust is the pin), the HKDF-SHA256
session-key schedule, and the binary ELT1 UDP data plane (HMAC gate, ECHO + observation block,
MTU probe) — byte-compatible with the Go server.
./gradlew :core-protocol:test # unit tests (crypto vectors, wire round-trip)
scripts/test-fmr.sh # live end-to-end test against the deployed server
test-fmr.sh mints an enrollment token over SSH, enrolls via the public control plane, computes
the SPKI pin from the served cert, and runs LiveServerTest — proving the client speaks the wire
protocol to the real server (enroll → profile → session → echo+observation → MTU → observations).
The live test self-skips when ECHOLOT_LIVE_* env vars are absent, so unit runs and CI stay green
offline.