connman: move host and resolver configuration to separate service

Setup system hostname, /etc/resolv.conf and /etc/hosts in a service
that can be run independently of connman.

The volatile etc files are created in /run/libreelec instead of
/run/connman so they can be modified similarily to standard linux
installations with a writable /etc. Connman can then hook into
that and move resolv.conf management to /run/connman/resolv.conf when
it's started.

If kernel IP configuration is used the resolv info from the kernel
will be used to create resolv.conf. Users can also provide their
own resolv.conf file in /storage/.config/resolv.conf which takes
precedence over ther kernel info. If no resolv.conf info is present
a fallback with use the Google nameservers is created (as before).

Loopback network interface setup has been removed, this is already
set up by systemd.

Signed-off-by: Matthias Reichl <hias@horus.com>

packages/network/connman/package.mk

@@ -59,12 +59,6 @@ post_makeinstall_target() {
   mkdir -p $INSTALL/usr/lib/connman
     cp -P $PKG_DIR/scripts/connman-setup $INSTALL/usr/lib/connman
 
-  mkdir -p $INSTALL/etc
-    ln -sf /run/connman/resolv.conf $INSTALL/etc/resolv.conf
-
-    # /etc/hosts must be writeable
-    ln -sf /run/connman/hosts $INSTALL/etc/hosts
-
   mkdir -p $INSTALL/etc/connman
     cp ../src/main.conf $INSTALL/etc/connman
     sed -i $INSTALL/etc/connman/main.conf \
@@ -78,9 +72,6 @@ post_makeinstall_target() {
         -e "s|^# PersistentTetheringMode.*|PersistentTetheringMode = true|g" \
         -e "s|^# NetworkInterfaceBlacklist = vmnet,vboxnet,virbr,ifb|NetworkInterfaceBlacklist = vmnet,vboxnet,virbr,ifb,docker,veth,zt|g"
 
-  mkdir -p $INSTALL/usr/config
-    cp $PKG_DIR/config/hosts.conf $INSTALL/usr/config
-
   mkdir -p $INSTALL/usr/share/connman/
     cp $PKG_DIR/config/settings $INSTALL/usr/share/connman/
 }

packages/network/connman/scripts/connman-setup

@@ -15,3 +15,11 @@
   else
     export CONNMAN_MAIN="--config=/etc/connman/main.conf"
   fi
+
+# switch resolv.conf management to connman and use current contents
+# as a fallback
+if [ -f /run/libreelec/resolv.conf ]; then
+  cat /run/libreelec/resolv.conf > /run/connman/resolv.conf
+fi
+rm -f /run/libreelec/resolv.conf
+ln -s /run/connman/resolv.conf /run/libreelec/resolv.conf

packages/network/connman/system.d/connman.service

@@ -3,7 +3,7 @@ Description=Connection service
 DefaultDependencies=false
 Conflicts=shutdown.target
 Before=network.target multi-user.target shutdown.target
-After=dbus.service
+After=dbus.service network-base.service
 Wants=network.target
 
 [Service]
@@ -11,10 +11,6 @@ Type=dbus
 BusName=net.connman
 Restart=on-failure
 EnvironmentFile=-/run/libreelec/debug/connman.conf
-ExecStartPre=-/bin/sh -c "echo -e 'nameserver 8.8.8.8\nnameserver 8.8.4.4' > /etc/resolv.conf"
-ExecStartPre=-/bin/sh -c "cat /storage/.cache/hostname > /proc/sys/kernel/hostname"
-ExecStartPre=-/bin/sh -c "cat /storage/.config/hosts.conf > /etc/hosts"
-ExecStartPre=/sbin/ifconfig lo 127.0.0.1 netmask 255.0.0.0 up
 ExecStart=/bin/sh -c ". /usr/lib/connman/connman-setup; exec /usr/sbin/connmand -nr $CONNMAN_MAIN $CONNMAN_DEBUG"
 StandardOutput=null
 RestartSec=2

packages/sysutils/systemd/package.mk

@@ -208,6 +208,11 @@ post_makeinstall_target() {
 
   mkdir -p $INSTALL/usr/sbin
   cp $PKG_DIR/scripts/kernel-overlays-setup $INSTALL/usr/sbin
+  cp $PKG_DIR/scripts/network-base-setup $INSTALL/usr/sbin
+
+  # /etc/resolv.conf and /etc/hosts must be writable
+  ln -sf /run/libreelec/resolv.conf $INSTALL/etc/resolv.conf
+  ln -sf /run/libreelec/hosts $INSTALL/etc/hosts
 
   # provide 'halt', 'shutdown', 'reboot' & co.
   ln -sf /usr/bin/systemctl $INSTALL/usr/sbin/halt
@@ -268,4 +273,5 @@ post_install() {
   enable_service usercache.service
   enable_service kernel-overlays.service
   enable_service hwdb.service
+  enable_service network-base.service
 }

packages/sysutils/systemd/scripts/network-base-setup

@@ -0,0 +1,26 @@
+#!/bin/sh
+
+# setup hostname
+if [ -f /storage/.cache/hostname ]; then
+  cat /storage/.cache/hostname > /proc/sys/kernel/hostname
+fi
+
+# setup /etc/hosts
+rm -f /run/libreelec/hosts
+if [ -f /storage/.config/hosts.conf ]; then
+  cat /storage/.config/hosts.conf > /run/libreelec/hosts
+fi
+
+# setup /etc/resolv.conf
+rm -f /run/libreelec/resolv.conf
+if [ -f /storage/.config/resolv.conf ]; then
+  cat /storage/.config/resolv.conf > /run/libreelec/resolv.conf
+elif [ -f /dev/.kernel_ipconfig -a -f /proc/net/pnp ]; then
+  cat /proc/net/pnp > /run/libreelec/resolv.conf
+else
+  cat << EOF > /run/libreelec/resolv.conf
+nameserver 8.8.8.8
+nameserver 8.8.4.4
+EOF
+fi
+

packages/sysutils/systemd/system.d/network-base.service

@@ -0,0 +1,12 @@
+[Unit]
+Description=Base Network Configuration
+DefaultDependencies=no
+After=local-fs.target systemd-tmpfiles-setup.service userconfig.service
+
+[Service]
+Type=oneshot
+ExecStart=/usr/sbin/network-base-setup
+RemainAfterExit=yes
+
+[Install]
+WantedBy=network.target