Crafter.Build's releases carry a Flatpak and nothing else since 2026-10-02 (imsd a625248): the rolling `latest` release's crafter-build-linux-x86_64-musl-v2.tar.gz that build-package.sh fetched is gone, so the push of 0.2.6 failed at `fetch crafter-build` (run 10, 2026-10-14, three 404s) and published nothing; the registry still serves 0.2.5. The move imsd made on 2026-10-04: install the Flatpak (net.catcrafts.CrafterBuild//stable from flatpak.catcrafts.net) in the job container and run it as crafter-build. bubblewrap inside the container needs a privileged runner, so the job runs on the `flatpak` label. The host keeps clang and llvm-ar for libqcomtee, which make-libqcomtee.sh compiles against the sysroot; the daemon's compiler, lld and libc++ are the Flatpak's, so the host packages that served the native test-suite run go. The sysroot gains llvm-runtimes, the package with the std module source of its own libc++ (libc++-dev ships none), added with --upgrade so a sysroot from before this change comes out with a matching libc++ and source. The README's Build section carries the install lines. Tested: build-package.sh run end to end on this commit in a privileged alpine:edge container (podman) on the workstation: crafter-build 2.1.0 (clang 23.1.2) from `stable`, the sysroot at libc++ and llvm-runtimes 23.1.3, daemon and agent cross-built, 8 suites passed natively, the three apks built, the daemon an aarch64 PIE against the sysroot's musl and libc++ (65 s). The rehearsed copy differs from this commit by the wrapping of one comment line.
5 KiB
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
With the Crafter Build Flatpak, which carries the compiler:
flatpak remote-add --if-not-exists flathub https://dl.flathub.org/repo/flathub.flatpakrepo
flatpak remote-add --if-not-exists catcrafts https://flatpak.catcrafts.net/catcrafts.flatpakrepo
flatpak install catcrafts net.catcrafts.CrafterBuild//stable
alias crafter-build='flatpak run net.catcrafts.CrafterBuild//stable'
crafter-build # bin/fingerprintd-<target>-<march>/fingerprintd
crafter-build test # the unit suites
Cross-compiling for the phone:
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
Lock-screen unlock
Two routes, both on by default:
- PAM. The daemon provides
fprintd, so a lock screen that runspam_fprintdbeside its password prompt unlocks by finger the usual way. Plasma's does (kde-fingerprint; thefingerprint-authandpostloginservices it needs are shipped here). Phosh's cannot: its PAM conversation answers every prompt with the password, so a fingerprint module in its stack would only stall the password behind the fingerprint timeout. - Standby. While the session in front on its seat is locked and the
display is on, the daemon runs a verify of its own and answers a match with
logind's
Session.Unlock, which Phosh honours. No verify runs while the display is off (an open verify polls the sensor at ~5 Hz; the display state comes from the backlight'sbl_poweror the panel's DRMdpms, and a device with neither is treated as always on). Any fprintd client takes precedence: aClaimcancels the standby verify, aReleasere-arms it. Only fingers named in that session owner's map unlock, and the map is re-read at every arm, so a finger deleted while locked stops counting at once. Per-fingerno-unlockrules apply here too, and every match is announced asFingerMatchedfor the session agent.--standby-unlock=offdisables it.
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.
Releases
Every push to main is built and tested by CI, which then publishes the
apks to the Forgejo Alpine registry that installed phones already point at.
CI treats the registry's "already published" answer as nothing to do, so a
push publishes only a package version new to the registry. The package
version is pkgver-rpkgrel: pkgver is the Version constant in
interfaces/Fingerprintd.cppm, pkgrel is the APKBUILD's and stays at 0.
An installed phone picks a published version up with plain apk upgrade.
From 0.2.6 on, a release is a range of commits ending in a bump commit
titled fingerprintd X.Y.Z that changes only the version: the constant and
the APKBUILD's pkgver. Each release is tagged vX.Y.Z on its bump commit
(signed, annotated) with the release notes as the tag message, and
published as a Forgejo release of the same name and text. No version
before 0.2.6 has a tag or release notes. The notes are written for the
people whose phones will upgrade:
fingerprintd X.Y.Z
## New
- **What a user can now do.** One bullet per change, the most important
first, with anything the user has to do inside the bullet.
## Fixes
- **What went wrong, in the user's terms.** What they saw, what changes,
what to do.
A section with nothing in it is left out, and so is behaviour the release
does not change. Versioning, from 0.2.6 on, is MAJOR.MINOR.PATCH: the
patch number counts releases, fixes and features alike; the minor number
moves when a release changes what a user can rely on the daemon for; the
major number moves when a release changes what an installed phone does
without being asked.
License
GPL-3.0-only, see LICENSE.
Copyright
Copyright (C) 2026 Catcrafts® catcrafts.net