networking: exts: introduce sanity checks, debug info

- protect against enabling networking exts directly
- debug logging
- fix typo in ext name

extensions/network/net-systemd-networkd.sh

@@ -0,0 +1,35 @@
+#
+# Extension to manage network interfaces with systemd-networkd + Netplan
+#
+function extension_prepare_config__install_systemd_networkd() {
+	# Sanity check
+	if [[ "${NETWORKING_STACK}" != "systemd-networkd" ]]; then
+		exit_with_error "Extension: ${EXTENSION}: requires NETWORKING_STACK='systemd-networkd', currently set to '${NETWORKING_STACK}'"
+	fi
+
+	display_alert "Extension: ${EXTENSION}: Installing additional packages" "netplan.io" "info"
+	add_packages_to_image netplan.io
+}
+
+function pre_install_kernel_debs__configure_systemd_networkd() {
+	display_alert "Extension: ${EXTENSION}: Enabling systemd-networkd" "" "info"
+
+	# Enable networkd and resolved
+	# Very likely not needed to enable manually since these services are enabled by default
+	chroot_sdcard systemctl enable systemd-networkd.service || display_alert "Failed to enable systemd-networkd.service" "" "wrn"
+	chroot_sdcard systemctl enable systemd-resolved.service || display_alert "Failed to enable systemd-resolved.service" "" "wrn"
+
+	# Copy network config files into the appropriate folders
+	display_alert "Configuring" "systemd-networkd and Netplan" "info"
+	local netplan_config_src_folder="${EXTENSION_DIR}/config-networkd/netplan/"
+	local netplan_config_dst_folder="${SDCARD}/etc/netplan/"
+
+	local networkd_config_src_folder="${EXTENSION_DIR}/config-networkd/systemd/network/"
+	local networkd_config_dst_folder="${SDCARD}/etc/systemd/network/"
+
+	run_host_command_logged cp -v "${netplan_config_src_folder}"* "${netplan_config_dst_folder}"
+	run_host_command_logged cp -v "${networkd_config_src_folder}"* "${networkd_config_dst_folder}"
+
+	# Change the file permissions according to https://netplan.readthedocs.io/en/stable/security/
+	chmod -v 600 "${SDCARD}"/etc/netplan/*
+}