# V2X2MAP bridge (vendored, bridge-only)

This is a pruned copy of the `bridge/` component of
[V2X2MAP](https://github.com/711it/v2x2map) 0.3.0, a receiver/live-map tool
for ITS-G5 V2X traffic. V2X2MAP is itself a fork of
[opentrafficmap/its-g5-receiver-firmware](https://codeberg.org/opentrafficmap/its-g5-receiver-firmware)
extended with BLE streaming, an Android app and a Windows installer — see
[the upstream project](https://github.com/711it/v2x2map) for the full
firmware/Android/iOS sources and license (MIT, `LICENSE` in this directory).

## Why it is here

`bridge/` is the host-side Python tool (serial/BLE ingestion, dashboard,
recording, VAM/CAM decoding) used for prototyping and to sanity-check VAM
decoding independently of this project's own `external/vanetza-idf`
stack. It has been locally modified to decode VAMs (`bridge/vam.py`,
`bridge/test_vam.py`, `bridge/asn1/`) and, since 2026-09-14, to look inside
signed GeoNetworking packets (`bridge/secured.py`: a bounded COER walk of the
TS 103 097 `Ieee1609Dot2Data` that returns the unsecured payload, PSID,
generation time and signer; the signature is **not** verified, the dashboard
says "signed … not verified").

The Android app and the receiver firmware from the original project are not
carried into this repository; this project uses its own ESP32-C5 firmware
(`firmware/`, `external/vanetza-idf/`) instead.
`bridge/firmware/*.bin` is a small set of prebuilt images kept only so the
bridge's recording/decode workflow can be exercised against a receiver board
without a separate firmware build.

## Use

See `bridge/its_g5_bridge.py` and `bridge/dashboard_server.py` for the
serial/BLE bridge and local dashboard; `bridge/vam.py` for the VAM decode
path. `bridge/requirements.txt` lists its Python dependencies (separate from
this project's own `station-link/python/requirements.txt`).