[Buildroot] [PATCH v3 2/3] package/wpa_supplicant: adding ifupdown support

[Angelo Compagnucci]

Actually, configuring a wifi interface as per "interfaces" man:

auto wlan0
iface wlan0 inet dhcp
wpa-conf /etc/wpa_supplicant.conf

doesn't work on buildroot because the line wpa-conf is ignored due to
the lack of a proper ifupdown script to handle the wpa_supplicant
initialization.

Signed-off-by: Angelo Compagnucci <angelo at amarulasolutions.com>
---
v1 -> v2:
* Simplify script to the minimum to have the service started (Thomas,
  Nicolas)
v2 -> v3:
* Move IF_WPA_CONF check early (Nicolas)

 package/wpa_supplicant/ifupdown.sh       | 49 ++++++++++++++++++++++++
 package/wpa_supplicant/wpa_supplicant.mk |  9 +++++
 2 files changed, 58 insertions(+)
 create mode 100755 package/wpa_supplicant/ifupdown.sh

diff --git a/package/wpa_supplicant/ifupdown.sh b/package/wpa_supplicant/ifupdown.sh
new file mode 100755
index 0000000000..569344b683
--- /dev/null
+++ b/package/wpa_supplicant/ifupdown.sh
@@ -0,0 +1,49 @@
+#!/bin/sh
+
+# This file is executed by ifupdown in pre-up, post-up, pre-down and
+# post-down phases of network interface configuration.
+
+WPA_SUP_BIN="/usr/sbin/wpa_supplicant"
+
+# run this script only for interfaces which have wpa-conf option
+[ -z "$IF_WPA_CONF" ] && exit 0
+
+# Allow wpa_supplicant interface to be specified via wpa-iface
+# useful for starting wpa_supplicant on one interface of a bridge
+if [ -n "$IF_WPA_IFACE" ]; then
+	WPA_IFACE="$IF_WPA_IFACE"
+else
+	WPA_IFACE="$IFACE"
+fi
+
+WPA_SUP_PIDFILE="/run/wpa_supplicant.${WPA_IFACE}.pid"
+
+do_start () {
+	if [ ! -s "$IF_WPA_CONF" ]; then
+		echo "cannot read contents of $IF_WPA_CONF"
+		exit 1
+	fi
+	WPA_SUP_CONF="-c $IF_WPA_CONF"
+}
+
+case "$MODE" in
+	start)
+		do_start
+		case "$PHASE" in
+			post-up)
+				start-stop-daemon -S -q -x ${WPA_SUP_BIN} \
+				-- -B -i ${WPA_IFACE} ${WPA_SUP_CONF} -P ${WPA_SUP_PIDFILE}
+				;;
+		esac
+		;;
+
+	stop)
+		case "$PHASE" in
+			pre-down)
+				start-stop-daemon -K -p ${WPA_SUP_PIDFILE}
+				;;
+		esac
+		;;
+esac
+
+exit 0
diff --git a/package/wpa_supplicant/wpa_supplicant.mk b/package/wpa_supplicant/wpa_supplicant.mk
index c4cfe03371..af97f36eda 100644
--- a/package/wpa_supplicant/wpa_supplicant.mk
+++ b/package/wpa_supplicant/wpa_supplicant.mk
@@ -250,6 +250,14 @@ define WPA_SUPPLICANT_INSTALL_STAGING_CMDS
 	$(WPA_SUPPLICANT_INSTALL_STAGING_WPA_CLIENT_SO)
 endef
 
+ifeq ($(BR2_PACKAGE_IFUPDOWN_SCRIPTS),y)
+define WPA_SUPPLICANT_INSTALL_IFUP_SCRIPTS
+	$(INSTALL) -m 0755 -D package/wpa_supplicant/ifupdown.sh \
+		$(TARGET_DIR)/etc/network/if-up.d/wpasupplicant
+	ln -sf ../if-up.d/wpasupplicant $(TARGET_DIR)/etc/network/if-down.d/wpasupplicant
+endef
+endif
+
 define WPA_SUPPLICANT_INSTALL_TARGET_CMDS
 	$(INSTALL) -m 0755 -D $(@D)/$(WPA_SUPPLICANT_SUBDIR)/wpa_supplicant \
 		$(TARGET_DIR)/usr/sbin/wpa_supplicant
@@ -259,6 +267,7 @@ define WPA_SUPPLICANT_INSTALL_TARGET_CMDS
 	$(WPA_SUPPLICANT_INSTALL_PASSPHRASE)
 	$(WPA_SUPPLICANT_INSTALL_DBUS)
 	$(WPA_SUPPLICANT_INSTALL_WPA_CLIENT_SO)
+	$(WPA_SUPPLICANT_INSTALL_IFUP_SCRIPTS)
 endef
 
 define WPA_SUPPLICANT_INSTALL_INIT_SYSTEMD
-- 
2.25.1