Add fingerprint functionality via fprintd DBus service

[quantum5]

For fun, I've ported swaywm#283 to run on this version of swaylock-effects. To enable fingerprint, build with -Dfingerprint=enabled.

[jirutka]

GitHub denied pushing into your branch, but allowed me to add commit via web interface. Weird.

ERROR: Permission to quantum5/swaylock-effects.git denied to jirutka.
fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists

[SebTM]

Would love to see this integrated into swaylock-effects and finally finding a home - otherwise you could have a look at this approach which would be sufficient to reach the same goal with some manual workarounds.

[quantum5]

Okay this should now build without fingerprint support. @jirutka is there anything else you want before merging?

[niksingh710]

@jirutka is this pr is in consideration?

[jirutka]

@jirutka is this pr is in consideration?

Yes, it is, I just need some time to test it.

[niksingh710]

@jirutka I have been using this pr and in my observation if it is build with fingerprint support then fingerprint works fine but manual password input fails to verify.

/etc/pam/swaylock

auth sufficient pam_fprintd.so
auth include login

after adding the pam_fprintd.so line in pam everything works fine.
it unlocks with password and fp both

[spikespaz]

Why is this PR needed? It already works for me on NixOS (nixpkgs tracks this fork). I can press Enter and then grace the fingerprint sensor to log in, or I can just type the password and press Enter as normal.

$ cat /etc/pam.d/swaylock

auth sufficient pam_unix.so try_first_pass nullok
auth sufficient /nix/store/m0d04vgf83hmfck6njjiphn5px7i1hz6-fprintd-1.94.2/lib/security/pam_fprintd.so

Edit:

swaywm#283 (comment)

Hm, do we really all of this complexity? I'd rather not do any of the D-Bus stuff. Can't users leverage a PAM module which integrates with the fingerprint reader instead?

Yes, we want to check password and fingerprint in parallel. With Pam closest solution is check fingerprint after empty password was entered.

With this MR we can touch fingerprint scanner while PC is asleep, it will wake up over USB and immediately unlock without necessety to press any button.

[niksingh710]

Why is this PR needed? It already works for me on NixOS (nixpkgs tracks this fork). I can press Enter and then grace the fingerprint sensor to log in, or I can just type the password and press Enter as normal.

This pr enables to scan fingerprint without the press of the enter key.
Either you scan your finger or enter password and press enter. (Makes the experience a bit Clean)
For me after pressing enter and trying to put finger and if it fails the manually entering password also fails but this pr resolves that too for me.

[spikespaz]

I don't know anything but would it be possible to use pkg-config to get the DBus interface?
systemd/systemd@1bd0cc4

Reason: PKG_CONFIG_DBUS_1_INTERFACES_DIR does not work in Nixpkgs.

Alternative:

postPatch = let
  dbusInterfacesDir = (pkgs.symlinkJoin {
    name = "${self.pname}-${self.version}_dbus-interfaces-dir";
    paths = self.buildInputs;
    pathsToLink = [ "share/dbus-1/interfaces" ];
  }) + "/share/dbus-1/interfaces";
in super.postPatch or "" + ''
  sed -i 's@/usr/share/dbus-1/interfaces@${dbusInterfacesDir}@g' \
    fingerprint/meson.build
'';

[spikespaz]

s/Fprint/fprintd/

[spikespaz]

s/Fprint/fprintd

[spikespaz]

s/Fprint/fprintd

[spikespaz]

It doesn't work when resuming from hibernation, works for suspend. Can anyone reproduce?