fp6-vendor-blobs 1-r3: extract from the active slot, and stop pinning a hash on a signed image

Two field units got no fingerprint sensor from fingerprintd 0.2.3's
manifest: its focal64 line pinned the sha256 of one Android build's
trustlet (16.82.0, the dev phone's), and Fairphone re-signs that trustlet
every release, so the pin matches exactly one of the six builds seen. A
user on 16.100.0 had to edit the manifest by hand; another ended up with
a file QTEE refuses.

The extractor now tries the active slot's partitions first
(androidboot.slot_suffix from the kernel command line): for a signed
image only the running TZ's own slot is guaranteed to load. An mbn line
may give '-' instead of a hash, which means structural verification
only: ELF64 header, every segment present at the size its program header
declares, page-aligned offsets, a sane total. The loader in TZ verifies
the signature and the per-segment hashes itself and refuses a damaged or
foreign image (one flipped byte -> ERROR_ELF_SIGNATURE_ERROR, measured),
so the whole-image hash added fragility and no protection. A real sha256
is still honoured, and the sha256 of what was installed is logged either
way.

--refresh re-derives mbn dests even when a file exists, replacing it
only with an image that verifies; consumers call it from
post-install/post-upgrade so a fresh 'apk add' needs no reboot and a
hand-placed or wrongly pinned trustlet is replaced on the next upgrade.

Verified on the dev phone (busybox): malformed inputs are refused with a
reason (missing, truncated or oversize segment; non-ELF, ELF32 or short
mdt; a garbage offset), both slots reassemble to the known-good hash, a
foreign file survives a plain run and is replaced by --refresh, a failed
refresh keeps the old file, pins still work, and the real post-upgrade
path re-derived the installed trustlet with the daemon restarting on it.
Record: fp6 repo journal/blobs/ and journal/fingerprint/, 2026-09-11.

aports/device/fp6-vendor-blobs/APKBUILD

@@ -10,11 +10,18 @@
 # their post-install/post-upgrade should also run
 # /usr/lib/fp6-vendor-blobs/extract --if-device so a package upgrade that
 # drops a previously-shipped blob restores the file immediately instead of
-# at the next boot. First consumer: soc-fairphone-fp6-audio (aw88261 acf).
+# at the next boot (--refresh in addition for an mbn consumer: it re-derives
+# the trustlet from the active slot even if a file is present). Consumers:
+# soc-fairphone-fp6-audio (aw88261 acf), fingerprintd (focal64 trustlet).
+#
+# 1-r3 (2026-09-11): active slot first, an unpinned ('-') structurally
+# verified mode for mbn, --refresh -- after two field units got no
+# fingerprint sensor from a whole-image hash pin that can only match one
+# Android build (fp6 repo journal/blobs/, journal/fingerprint/).
 maintainer="Jorijn van der Graaf <jorijnvdgraaf@catcrafts.net>"
 pkgname=fp6-vendor-blobs
 pkgver=1
-pkgrel=2
+pkgrel=3
 pkgdesc="On-device extraction of vendor blobs from the stock Android partitions"
 url="https://forgejo.catcrafts.net/Catcrafts/fp6-img"
 arch="noarch"
@@ -55,7 +62,7 @@ package() {
 }
 
 sha512sums="
-2caafdedf93e103516834a1f815dd828ecee66c82d569e4a925ccc6bd6ac75d6778290adb02db69538af3bb6ad36cee5c13c8afba2c722a4c4550efe761ba8a0  fp6-vendor-blobs-extract
+e9618b4a1ccbe0913a608b32a1a9e87337e3da79a3d7ccc7f49292ae9aaa9406d2ea9817d63b3cfff2c4346b80dd2476c10725f4f0f95c859acd17b22ec03a16  fp6-vendor-blobs-extract
 b4c290095d9f39515378dfef08de720ce49324210342aa13c131dfce1103785e796e6f821f0c659671a4c44b46f466ce0e03f11f216fdcdee2a99db5e7970800  fp6-vendor-blobs.service
 9e79dd0aed13f11a71282aa24b2a26331e85c105e25ab0c0fed6189b8c300769a5f4308b18b91d9855868d658ad3a57c03e26c9b11bd27fd5e03f9a5decbbd6a  fp6-vendor-blobs.preset
 "