feat(systemd-creds): introducing the systemd-creds module

Introducing the systemd-creds module.

modules.d/01systemd-creds/module-setup.sh

@@ -0,0 +1,46 @@
+#!/bin/bash
+# This file is part of dracut.
+# SPDX-License-Identifier: GPL-2.0-or-later
+
+# Prerequisite check(s) for module.
+check() {
+
+    # If the binary(s) requirements are not fulfilled the module can't be installed.
+    require_binaries systemd-creds || return 1
+
+    # Return 255 to only include the module, if another module requires it.
+    return 255
+
+}
+
+# Module dependency requirements.
+depends() {
+    local deps
+
+    # This module has external dependency on other module(s).
+    deps="systemd"
+    systemd-creds -q has-tpm2 && deps+=" tpm2-tss"
+    echo "$deps"
+
+    # Return 0 to include the dependent module(s) in the initramfs.
+    return 0
+
+}
+
+# Install the required file(s) and directories for the module in the initramfs.
+install() {
+
+    inst_multiple -o \
+        "/usr/lib/credstore/*" \
+        "/usr/lib/credstore.encrypted/*" \
+        "$tmpfilesdir/credstore.conf" \
+        systemd-creds
+
+    # Install the hosts local user configurations if enabled.
+    if [[ $hostonly ]]; then
+        inst_multiple -H -o \
+            "/etc/credstore/*" \
+            "/etc/credstore.encrypted/*"
+    fi
+
+}