The fingerprint matcher is a proprietary OEM-signed trustlet, and it is not
shipped as one file: QTEE images live in the modem partition's image/ as an
ELF header+hashes file plus one payload per program header, and the loader
wants each payload written back at its segment's p_offset. So the existing
file directive cannot reach it.
An mbn directive does, with the same guarantees file has: the sha256 is of
the reassembled image, a mismatch tries the next partition, and an unverified
image is never installed. Reassembly is not a concatenation -- segments are
page aligned but not contiguous, gaps stay zero, and two pairs of focal64's
nine segments share an offset, so they are written in index order and the
later one wins, exactly as the bring-up repo's reassemble.py does.
Verified on the dev phone against the hash QTEE has actually accepted since
August: 3600472 bytes, sha256 1930c490..., reassembled from the phone's own
modem_a. The retry path was verified too, with a deliberately wrong first
partition -- which is how the variable clobber got caught: POSIX sh has no
locals, and reassemble() taking rdir= rewrote its caller's copy to the mount
path, so the second partition would have been searched at $MNT/$MNT/...
The fast path needed teaching as well: mbn's dest is the fifth field, and a
first boot would otherwise have exited early and extracted nothing.
Not pushed. The consumer fragment lives in the fingerprintd package.
New package fp6-vendor-blobs: a manifest-driven systemd oneshot that
copies proprietary blobs out of the stock Android partitions on first
boot. pmOS installs flash only boot+userdata, so every installed unit
still carries the stock vendor/dsp partitions - the device duplicates a
file it already contains, for its own operation, and nothing proprietary
is distributed by us. Partitions are mounted read-only (ext4 additionally
with noload - not even a journal replay touches the stock data), every
copy is sha256-pinned and a miss fails loudly, and the consuming devices
are unbound and re-probed afterwards so the feature works the same boot.
The rebind is unconditional by design: aw88261 binds on a bare i2c
chip-id probe and requests the ACF only at ASoC card init (~21 s, after
SoundWire enumeration), so a bound device can still be one that lost the
firmware race - and that failed request is never retried.
soc-fairphone-fp6-audio (pkgver 4) stops shipping the blob, installs the
manifest fragment instead, and re-runs the extractor from
post-install/post-upgrade so upgrades restore the file immediately (the
old package version removed it on upgrade). License drops back to plain
BSD-3-Clause - nothing proprietary left in the package.
Verified on the dev phone (fp6 repo journal/blobs/captures/
2026-08-24-first-boot-extractor-verification.txt): first-boot extraction
+ same-boot audio, mid-session post-upgrade recovery, and the everyday
fast-path no-op; committed files byte-identical to the tested deployment.
Assisted-by: Claude:claude-fable-5
