mrambossekandClaude Fable 5
b5c8dda9a2
Authorization code with PKCE, a Sign in card in settings, and the echolot://auth redirect handled next to the enrolment one - told apart by host, because one spends a token and the other completes an authorization, and confusing them would fail obscurely. The detail that decides whether this survives a real phone: the PKCE verifier is written to storage before the browser opens rather than held in memory. Handing control to a browser backgrounds the process and Android may kill it, so the callback arrives at a fresh one. An in-memory verifier works on a developer's device and fails under memory pressure. Pending state is cleared before the exchange is attempted, whatever the outcome: it is single-use, and leaving it behind would let a later callback complete a flow nobody started. Also records an open issue the question about server requirements surfaced: two probes hardcode the reference deployment, so a user with no server still sends DNS and STUN traffic to fmr without being told. For a tool this careful about what leaves the device, that is the wrong default. Co-Authored-By: Claude Fable 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.