mrambossekandClaude Opus 5
3520eabd21
Multi-module Android app, built bottom-up from a verifiable core. core-protocol is pure Kotlin/JVM (no Android SDK): SPKI-pinned control plane (enroll/profile/session over HttpsURLConnection — API-1 compatible, hostname verification off, trust is the pin), HKDF-SHA256 session keys, ELT1 UDP data plane (HMAC gate, ECHO+observation, MTU probe) — byte-compatible with the Go server. Unit tests incl. the RFC 5869 HKDF vector (key derivation provably matches the server). LiveServerTest + scripts/test-fmr.sh prove the client end-to-end against the deployed fmr server: profile (8 caps), session, ECHO rtt~11ms with the observation block returning our observed NAT port, MTU 1400->1400, observations. Live test self-skips without ECHOLOT_LIVE_*. Two client bugs caught live: java.net.http hostname verification (→ HttpsURLConnection, also the Android-minSdk-26 choice) and ECHO padding needed for the observation to survive anti-amplification. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Echolot
Free software for detecting and debugging local network issues from an Android phone — built for people who actually know what a neighbor table is.
Most "wifi analyzer" apps show you signal bars. Echolot aims at the layer where home and office networks actually break: duplicate DHCP servers, broken IPv6 RAs, MTU black holes, NAT64 weirdness, multicast that dies at the AP, DNS that answers differently than it should. It records what it observed, separates observation from interpretation, and exports the whole run so you can argue with it later.
Status: pre-release. The capability prober runs on real hardware; the production app and the probe server are not built yet.
Repository layout
docs/ design docs — the contract for everything below
echolot-prober/ capability prober: validates the no-root feasibility matrix on real devices
The Go probe server and the production app land here as siblings.
Design docs
The three specs are draft-complete and reviewed; treat them as the contract.
| Doc | What it defines |
|---|---|
| docs/feature-catalog-and-feasibility.md | Full feature list + the no-root feasibility matrix |
| docs/measurement-schema.md | Archived/exportable measurement JSON (observation vs finding, two-clock rule, anonymization) |
| docs/probe-protocol.md | Client↔server wire protocol (pinned TLS control plane, binary UDP data plane, STUN, canary DNS) |
| docs/build-status.md | Running log of decisions and next steps |
Privilege tiers
Every result records which tier produced it:
app— no root, no special setup. The bulk of the functionality.shizuku— ADB-shell privileges via wireless pairing, no root. Shipped in v1.root— future optional module.
Licensing
| Part | License | Why |
|---|---|---|
| All code (app, prober, server) | GPL-3.0-or-later | The value here is the platform-API research; copyleft keeps derivative apps free |
docs/ (the specs) |
CC-BY-4.0 | A wire protocol and a measurement format should be implementable by anyone, without license anxiety |
Full texts: LICENSE (GPLv3) and docs/LICENSE (CC BY 4.0).
Sources carry SPDX-License-Identifier headers.
If you want to build a compatible server or client, the protocol and schema docs are deliberately permissive — go ahead.
Building
See echolot-prober/README.md. Short version, from echolot-prober/:
echo "sdk.dir=/path/to/Android/sdk" > local.properties
./gradlew :app:assembleDebug