build: add option to use preinit IP as LAN IP

We currently have build options to customize the IP address used in the
preinit phase of the boot process, but not to set the default LAN IP.

Introduce a boolean build option that, when enabled, results in the IP
address configured for the preinit phase, to be also used as the default
LAN IP address.

Signed-off-by: Stijn Tintel <[email protected]>

package/base-files/Makefile

@@ -89,6 +89,19 @@ define ImageConfigOptions
 	echo 'pi_preinit_net_messages="$(CONFIG_TARGET_PREINIT_SHOW_NETMSG)"' >>$(1)/lib/preinit/00_preinit.conf
 	echo 'pi_preinit_no_failsafe_netmsg="$(CONFIG_TARGET_PREINIT_SUPPRESS_FAILSAFE_NETMSG)"' >>$(1)/lib/preinit/00_preinit.conf
 	echo 'pi_preinit_no_failsafe="$(CONFIG_TARGET_PREINIT_DISABLE_FAILSAFE)"' >>$(1)/lib/preinit/00_preinit.conf
+ifeq ($(CONFIG_TARGET_DEFAULT_LAN_IP_FROM_PREINIT),y)
+	mkdir -p $(1)/etc/board.d
+	echo '. /lib/functions/uci-defaults.sh' >$(1)/etc/board.d/99-lan-ip
+	echo 'logger -t 99-lan-ip "setting custom default LAN IP"' >>$(1)/etc/board.d/99-lan-ip
+	echo 'board_config_update' >>$(1)/etc/board.d/99-lan-ip
+	echo 'json_select network' >>$(1)/etc/board.d/99-lan-ip
+	echo 'json_select lan' >>$(1)/etc/board.d/99-lan-ip
+	echo 'json_add_string ipaddr $(if $(CONFIG_TARGET_PREINIT_IP),$(CONFIG_TARGET_PREINIT_IP),"192.168.1.1")' >>$(1)/etc/board.d/99-lan-ip
+	echo 'json_add_string netmask $(if $(CONFIG_TARGET_PREINIT_NETMASK),$(CONFIG_TARGET_PREINIT_NETMASK),"255.255.255.0")' >>$(1)/etc/board.d/99-lan-ip
+	echo 'json_select ..' >>$(1)/etc/board.d/99-lan-ip
+	echo 'json_select ..' >>$(1)/etc/board.d/99-lan-ip
+	echo 'board_config_flush' >>$(1)/etc/board.d/99-lan-ip
+endif
 endef
 
 define Build/Prepare

package/base-files/image-config.in

@@ -5,6 +5,13 @@
 # See /LICENSE for more information.
 #
 
+config TARGET_DEFAULT_LAN_IP_FROM_PREINIT
+	bool "Use preinit IP configuration as default LAN IP" if IMAGEOPT
+	default n
+	help
+		Enabling this will set the default LAN IP address and netmask
+		to the preinit values set in the image config.
+
 menuconfig PREINITOPT
 	bool "Preinit configuration options" if IMAGEOPT
 	default n