/python-validity

Validity fingerprint sensor prototype

Primary LanguagePython

python-validity

Validity fingerprint sensor library. Originally designed to capture some of my findings for 138a:0097, but if you manage to get it working for some other Validity sensor - pull requests are welcome.

Setting up

To install Python dependencies run

$ pip3 install -r requirements.txt

Initialization

Automatic factory reset, pairing and firmware flashing

This repo includes validity-sensors-tools.py, a simple collection of tools that helps initializing Validity fingerprint readers under linux, loading their binary firmware and initializing them.

This tool currently only supports these sensors:

  • 138a:0090 Validity Sensors, Inc. VFS7500 Touch Fingerprint Sensor
  • 138a:0097 Validity Sensors, Inc. Which are present in various ThinkPad and HP laptops.

These devices communicate with the laptop via an encrypted protocol and they need to be paired with the host computer in order to work and compute the TLS keys. Such initialization is normally done by the Windows driver, however thanks to the amazing efforts of Viktor Dragomiretskyy (uunicorn), and previously of Nikita Mikhailov, we have reverse-engineerd the pairing process, and so it's possible to do it under Linux with only native tools as well.

The procedure is quite simple:

  • Device is factory-reset and its flash repartitioned
  • A TLS key is negotiated, generated via host hw ID and serial
  • Windows driver is downloaded from Lenovo to extract the device firmware
  • The device firmware is uploaded to the device
  • The device is calibrated

For 138a:0097 it's also possible to enroll fingers in the internal storage doing: validity-sensors-tools.py --tool enroll --finger-id [0-9]

Once the chip is paired with the computer via this tool, it's possible to use it in libfprint using the driver at

Installing it as snap

This tool can be easily installed almost every linux distribution with all its dependencies as snap.

To do so:

sudo snap install validity-sensors-tools

# Give it access to the usb devices
sudo snap connect validity-sensors-tools:raw-usb
sudo snap connect validity-sensors-tools:hardware-observe

# Initialize the device
sudo validity-sensors-tools.initializer

# Test the device
sudo validity-sensors-tools.led-test

# See other avilable tools
validity-sensors-tools --help

Get it from the Snap Store

Installing from AUR on Arch Linux

Install validity-sensors-tools-git[AUR].

You can run it as validity-sensors-tools:

sudo validity-sensors-tools -t led-dance

Getting the firmware

It's possible to just extract official Lenovo device driver for vfs0097 or driver for vfs0090 (also part of the SCCM package using innoextract (available for all the distros), or wine.

The only reason you need to do this is to find 6_07f_lenovo_mis.xpfwext (for vfs0097) or 6_07f_Lenovo.xpfwext (for vfs0090) and copy it to this project location.

  innoextract n1mgf03w.exe -e -I 6_07f_lenovo_mis.xpfwext # vfs0097
  innoextract n1cgn08w.exe -e -I 6_07f_Lenovo.xpfwext # vfs0090

Factory reset

If your device was previously paired with another OS or computer, you need to do a factory reset. This will erase all fingers from the internal database and make the device ready for pairing.

$ python3 factory-reset.py
$

Pairing

After performing a factory reset you need to pair your device with a host computer. This must be done only once, before you can enroll/identify/verify fingers.

$ python3 pair.py
Initializing flash...
Detected Flash IC: W25Q80B, 1048576 bytes
Clean slate
Uploading firmware...
Sensor: VSI 55E  FM209-001
Loaded FWExt version 1.1 (Sat Feb  3 05:07:30 2018), 8 modules
Calibrating...
Sensor: VSI 55E  FM209-001
FWExt version 1.1 (Sat Feb  3 05:07:30 2018), 8 modules
Calibration data loaded from the file.
Init database...
Creating a new user storage object
Creating a host machine GUID record
That's it, pairing's finished
$ 

Examples

Here is a couple of examples of how you can use this library. All examples assume that your device is already paired.

Initialize a session

Before talking to a device you will need to open it and start a new TLS session

$ python3
Python 3.6.7 (default, Oct 22 2018, 11:32:17) 
[GCC 8.2.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> from prototype import *
>>> open97()
>>>

Or load previosly saved TLS session (see comments in holdthedoor.py)

$ python3
Python 3.6.7 (default, Oct 22 2018, 11:32:17) 
[GCC 8.2.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> from prototype import *
>>> load97()
>>> 

Enroll a new user

Note: 0xf5 == WINBIO_FINGER_UNSPECIFIED_POS_01 (see ms docs)

>>> db.dump_all()
 8: User S-1-5-21-111111111-1111111111-1111111111-1000 with 1 fingers:
     9: f5 (WINBIO_FINGER_UNSPECIFIED_POS_01)
>>> enroll(sid_from_string('S-1-5-21-394619333-3876782012-1672975908-3333'), 0xf5)
Waiting for a finger...
Progress: 14 % done
Progress: 28 % done
Progress: 42 % done
Progress: 57 % done
Progress: 71 % done
Progress: 85 % done
Progress: 100 % done
All done
11
>>> db.dump_all()
 8: User S-1-5-21-111111111-1111111111-1111111111-1000 with 1 fingers:
     9: f5 (WINBIO_FINGER_UNSPECIFIED_POS_01)
10: User S-1-5-21-394619333-3876782012-1672975908-3333 with 1 fingers:
    11: f5 (WINBIO_FINGER_UNSPECIFIED_POS_01)
>>> 

Delete database record (user/finger/whatever)

>>> db.dump_all()
 8: User S-1-5-21-111111111-1111111111-1111111111-1000 with 1 fingers:
     9: f5 (WINBIO_FINGER_UNSPECIFIED_POS_01)
10: User S-1-5-21-394619333-3876782012-1672975908-3333 with 1 fingers:
    11: f5 (WINBIO_FINGER_UNSPECIFIED_POS_01)
>>> db.del_record(11)
>>> db.dump_all()
 8: User S-1-5-21-111111111-1111111111-1111111111-1000 with 1 fingers:
     9: f5 (WINBIO_FINGER_UNSPECIFIED_POS_01)
10: User S-1-5-21-394619333-3876782012-1672975908-3333 with 0 fingers:
>>> 

Identify a finger (scan)

>>> identify()
Recognised finger f5 (WINBIO_FINGER_UNSPECIFIED_POS_01) from user S-1-5-21-111111111-1111111111-1111111111-1000
Template hash: 36bc1fe077e59a3090c816fcf2798c30a85d8a8fbe000ead5c6a946c3bacef7b

DBus service

Sources contain a simple DBus service which can impersonate fprint daemon. Install fprint, edit /usr/share/dbus-1/system-services/net.reactivated.Fprint.service by commenting out activation info:

#Exec=/usr/lib/fprintd/fprintd
#User=root
#SystemdService=fprintd.service

start a fake service with something like this:

while sleep 1; do
    python3 dbus-service.py
    echo "====restart==="
done

Debugging

If you are curious you can enable tracing to see what flows in and out of device before and after encryption

>>> tls.trace_enabled=True
>>> usb.trace_enabled=True
>>> db.dump_all()
>tls> 17: 4b00000b0053746757696e64736f7200
>cmd> 1703030050c00a7ff1cf76e90f168141b4bc519ca9598eacb575ff01b7552a3707be8506b246d5272cb119e7b8b3eccd991cb7d8387245953ff1da62cebfb07fae7e47b9b536fb1a82185cc9399d30625ee3c1451f
<cmd< 1703030050b7a4a39e256bbe5a2589a6fbeec86057bead96f0b79ab6657dd9e851efaccddf9cd0108865aa98c510a1f8cd9b881b3166db553e5b4330c437f09daccbe261b259019774466ddb0d7f97fa67b6337329
<tls< 17: 0000030002000b00000008004c000a004c0053746757696e64736f7200
>tls> 17: 4a080000000000
>cmd> 1703030040ef982e5d6c403ff636c44cd53e7d0f98c21f67ff3b5b80f53555e4547028bd4d17cf5b0539ac0489238f1f066b8ba849120380cf979088d6c63249c873868c95
<cmd< 1703030090f16f4ed027f50103d5cf274a59323e5f25e084e21e4d42d4eab23abc867504ef80a700c775f03c0fafabee2e373fbf551d46e53ca957b86c53853a913e11c8cab98df41afc86af883b4e1b817024b212dbcdf1057a3bcdbc474381c5a5c37162167ff395e8102902c4e0d00b9b4931f0fa986ec3257c6bf2a5b55ea0b5349c035c20ed583522ac7ef9048e97a589a25e
<tls< 17: 00000800010000004c000900f5000300780b030000001c000000010500000000000515000000c76b9f06c7353a42c7353a42e803000000000000000000000000000000000000000000000000000000000000000000000000000000000000
>tls> 17: 4a0a0000000000
>cmd> 1703030040b522c55b73480e0d71a322abf8b65d97c9b55e9930206c463f998886cda4410d1b00ab41ec5b213d2ac18bf3bf61ce817446f27d643f99aba5a1d4cb80d18461
<cmd< 170303009061cef46670a21ca87043f1f4d55153eb46a19757de767d4ddbee736e2a775af63850a89ebe814b7e578979f1fb8a1c2133e0c6fa5b468cff9c731ef3f178b33334bdf64c03903dc2d95e9a16c656f1f8d06fa3431c3971607fec56f104ec7d4e73518705a289fac53fe54ddf33b30dad2b8c1fac67b7decf8c7f86dd843414e7f056a2ea8366611e5094c5491d5ade46
<tls< 17: 00000a00000000004c00030000001c000000010500000000000515000000c5698517bcff12e72496b763050d000000000000000000000000000000000000000000000000000000000000000000000000000000000000
 8: User S-1-5-21-111111111-1111111111-1111111111-1000 with 1 fingers:
     9: f5 (WINBIO_FINGER_UNSPECIFIED_POS_01)
10: User S-1-5-21-394619333-3876782012-1672975908-3333 with 0 fingers:
>>>