Autologin, unlock the keyring with the luks password

Signed-off-by: Hadi <112569860+anotherhadi@users.noreply.github.com>

nixos/autologin.nix

@@ -0,0 +1,27 @@
+# Autologin at boot: greetd starts your session directly on the first VT
+{
+  pkgs,
+  config,
+  lib,
+  ...
+}: {
+  services.greetd.settings.initial_session = {
+    command = "${pkgs.uwsm}/bin/uwsm start -e -D Hyprland hyprland.desktop";
+    user = config.var.username;
+  };
+
+  # Needed so the LUKS passphrase entered at boot is cached in the kernel
+  # keyring, where pam_fde_boot_pw can retrieve it (see below).
+  boot.initrd.systemd.enable = true;
+
+  security.pam.services.greetd.rules.session.fde_boot_pw = {
+    order = 12550; # kwallet=12500, gnome_keyring=12600: must run in between
+    control = "optional";
+    modulePath = "${pkgs.pam_fde_boot_pw}/lib/security/pam_fde_boot_pw.so";
+    args = ["inject_for=gkr"];
+  };
+
+  security.pam.services.login.enableGnomeKeyring = true;
+
+  systemd.services.greetd.serviceConfig.KeyringMode = lib.mkForce "shared";
+}