[RFC] iptables: add systemd helper unit to load/restore rules

[Jack Mitchell <ml@embed.me.uk>]

From: Jack Mitchell <jack@embed.me.uk>

there is currently no way to automatically load iptable rules
in OE. Add a systemd unit file to automatically load rules on
network connection. This is cribbed from the way ArchLinux
handles iptables with some minor modifications for OE. New rules
can be generated using 'iptables-save > iptables.rules'
---
 .../iptables/iptables/iptables.rules                 |  0
 .../iptables/iptables/iptables.service               | 13 +++++++++++++
 meta/recipes-extended/iptables/iptables_1.6.0.bb     | 20 ++++++++++++++++++--
 3 files changed, 31 insertions(+), 2 deletions(-)
 create mode 100644 meta/recipes-extended/iptables/iptables/iptables.rules
 create mode 100644 meta/recipes-extended/iptables/iptables/iptables.service

diff --git a/meta/recipes-extended/iptables/iptables/iptables.rules b/meta/recipes-extended/iptables/iptables/iptables.rules
new file mode 100644
index 0000000..e69de29
diff --git a/meta/recipes-extended/iptables/iptables/iptables.service b/meta/recipes-extended/iptables/iptables/iptables.service
new file mode 100644
index 0000000..041316e
--- /dev/null
+++ b/meta/recipes-extended/iptables/iptables/iptables.service
@@ -0,0 +1,13 @@
+[Unit]
+Description=Packet Filtering Framework
+Before=network-pre.target
+Wants=network-pre.target
+
+[Service]
+Type=oneshot
+ExecStart=@SBINDIR@/iptables-restore /etc/iptables/iptables.rules
+ExecReload=@SBINDIR@/iptables-restore /etc/iptables/iptables.rules
+RemainAfterExit=yes
+
+[Install]
+WantedBy=multi-user.target
diff --git a/meta/recipes-extended/iptables/iptables_1.6.0.bb b/meta/recipes-extended/iptables/iptables_1.6.0.bb
index fbbe418..65430a1 100644
--- a/meta/recipes-extended/iptables/iptables_1.6.0.bb
+++ b/meta/recipes-extended/iptables/iptables_1.6.0.bb
@@ -22,13 +22,16 @@ SRC_URI = "http://netfilter.org/projects/iptables/files/iptables-${PV}.tar.bz2 \
            file://types.h-add-defines-that-are-required-for-if_packet.patch \
            file://0001-configure-Add-option-to-enable-disable-libnfnetlink.patch \
            file://0002-configure.ac-only-check-conntrack-when-libnfnetlink-enabled.patch \
-          "
+           file://iptables.service \
+           file://iptables.rules \
+"
+
 SRC_URI_append_libc-musl = " file://0001-fix-build-with-musl.patch"
 
 SRC_URI[md5sum] = "27ba3451cb622467fc9267a176f19a31"
 SRC_URI[sha256sum] = "4bb72a0a0b18b5a9e79e87631ddc4084528e5df236bc7624472dcaa8480f1c60"
 
-inherit autotools pkgconfig
+inherit autotools pkgconfig systemd
 
 EXTRA_OECONF = "--with-kernel=${STAGING_INCDIR} \
                "
@@ -48,3 +51,16 @@ do_configure_prepend() {
 	# Keep ax_check_linker_flags.m4 which belongs to autoconf-archive.
 	rm -f libtool.m4 lt~obsolete.m4 ltoptions.m4 ltsugar.m4 ltversion.m4
 }
+
+do_install_append() {
+
+        install -d ${D}${sysconfdir}/iptables
+        install -m 0644 ${WORKDIR}/iptables.rules ${D}${sysconfdir}/iptables
+
+        install -d ${D}${systemd_unitdir}/system
+        install -m 0644 ${WORKDIR}/iptables.service ${D}${systemd_unitdir}/system
+
+	sed -i -e 's,@SBINDIR@,${sbindir},g' ${D}${systemd_unitdir}/system/iptables.service
+}
+
+SYSTEMD_SERVICE_${PN} = "iptables.service"
-- 
2.9.3