fingerprintd/README.md
2026-09-08 16:50:32 +02:00

48 lines
No EOL
1.7 KiB
Markdown

# fingerprintd
Fingerprint daemon for the Fairphone 6 (`milos`, SM7635) on mainline Linux.
`fingerprintd-core` is a static library with no GLib, no libqcomtee and no
system headers. Everything in it is a wire format or a state machine that was
recovered by reverse-engineering, so all of it is pinned by tests that run on a
dev box with no phone, no TEE and no sensor. The daemon shell holds everything
that touches hardware.
## Build
```sh
crafter-build # bin/fingerprintd-<target>-<march>/fingerprintd
crafter-build test # the unit suites
```
Cross-compiling for the phone:
```sh
packaging/make-sysroot.sh
crafter-build -- --target=aarch64-alpine-linux-musl --sysroot=~/.cache/fingerprintd/sysroot-aarch64-alpine --march=armv8.6-a+fp16fml+aes+sha3+sm4 --mtune=cortex-a720
crafter-build test --target=aarch64-alpine-linux-musl --sysroot=~/.cache/fingerprintd/sysroot-aarch64-alpine --march=armv8.6-a+fp16fml+aes+sha3+sm4 --mtune=cortex-a720
```
Verified on the device: all five suites pass cross-built and run on the phone
itself, not only under emulation.
```
fprintd-enroll -f right-index-finger user ten stages, enroll-completed
fprintd-list user - #0: right-index-finger
fprintd-verify user (wrong finger) verify-no-match, on the first press
fprintd-verify user (enrolled finger) verify-match, on the first press
```
## Runtime dependencies
The `focal64` trustlet is proprietary and is not in this repo. It is
extracted from the device's own stock Android partition on first boot by the
`fp6-vendor-blobs` mechanism, the same way other firmware in fp6-img is.
## License
GPL-3.0-only, see LICENSE.
## Copyright
Copyright (C) 2026 Catcrafts® catcrafts.net