This is a FIDO2 USB security key implementation for the $5 Raspberry Pi Zero.
You can use it with any FIDO2-compatible browser (Google Chrome or Chromium) and any website supporting FIDO2 WebAuthN.
It is experimental -- please do not rely on this for use cases with strong security requirements.
- Ed25519 attestation
- Deterministic ECDSA attestation with P-256
- Adafruit OLED screen and button support (optional)
- PIN protocol support (optional)
- Simple backup and restore: a single file is used for all state
- FIDO2 is supported, but U2F is not
Download the latest release, then run java -jar pi-zero-security-key.jar with superuser privileges.
If you prefer to build from source, you must checkout pi-ssd1306-java and run ./gradlew publishToMavenLocal. Then, to build, run ./gradlew shadowJar in this repo.
Note that your kernel must be compiled with ConfigFS USB gadget support. Raspbian appears to support this by default.
All state is stored in config.json, which is created on first run. Common options:
| Option | Type | Description |
|---|---|---|
enabledAlgorithms |
string array | A list of attestation algorithms, ordered from most to least preferred. Valid values are Ed25519 and P256_ECDSA. |
enableBonnet |
boolean | Whether to expect button presses from, and display auth/register status using, an Adafruit OLED Bonnet |