Support for Synaptics 06cb:00a2 Metallica MOH - need help extracting init blob

[yousefnune-commits]

Device: Synaptics 06cb:00a2 Metallica MOH Touch Fingerprint Reader
OS: Ubuntu 24.04
Progress so far:

Device visible in lsusb
Added 0x00a2 to usb.py and blobs.py alongside 0x009a
Service starts successfully now
But fails with: Exception: Failed: 04be
This means init_hardcoded from blobs_9a.py is rejected by 00a2

Need help:

Extracting correct init blob from Windows USB traffic
Should we create a separate blobs_a2.py?
Any tools or scripts to capture init sequence on Windows?

[dmitriy-myz]

I have had some work on adding this;
About progress:
It could retrieve image from sensor and save it to file.
Also it could match fingers already added on Windows to chip databases

What it could not: add finger into database.

MOH on name means Match on Host. This device looks combined: it could match on device if host did compute with on inital fingerprint adding.

So from what I see it could match on host using some Minutiae-based comparison.
Or some disassembly required on windows blob to proceed finger data and send some processed data to sensor so it could match by itself.
Here is my changes
master...dmitriy-myz:python-validity:add-a2

[Burghalim72]

@dmitriy-myz For me, attempting to use your code only results in 04be error as well. I was unable to use fingerprints added on Windows either, because then there was signature verification error, requiring factory reset.

[dmitriy-myz]

@Burghalim72 probably mismatch on product ID between win and Linux you might try to hardcode it to values from Windows device. For me it worked with finger added in windows (But I used Virtualbox/wine to add fingerprint)
https://github.com/dmitriy-myz/python-validity/blob/add-a2/validitysensor/tls.py#L95

[Burghalim72]

@dmitriy-myz I put product ID values into VirtualBox machine config and removed actual hardcoded value present in moh-opencv-poc branch. Looks like it works now. I wonder if recent blob update needs to be backported to add-a2 branch.