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-rwxr-xr-xusr/lib/systemd/readonly-root204
1 files changed, 204 insertions, 0 deletions
diff --git a/usr/lib/systemd/readonly-root b/usr/lib/systemd/readonly-root
new file mode 100755
index 00000000..a3679580
--- /dev/null
+++ b/usr/lib/systemd/readonly-root
@@ -0,0 +1,204 @@
+#!/bin/bash
+#
+# Set up readonly-root support.
+#
+
+. /etc/init.d/functions
+
+# We need to initialize the $HOSTNAME variable by ourselves now:
+# (It was previously done for RHEL-6 branch, but got lost in time.)
+HOSTNAME="$(hostname)"
+
+# Check SELinux status
+SELINUX_STATE=
+if [ -e "/sys/fs/selinux/enforce" ] && [ "$(cat /proc/self/attr/current | tr -d '\000' )" != "kernel" ]; then
+ if [ -r "/sys/fs/selinux/enforce" ] ; then
+ SELINUX_STATE=$(cat "/sys/fs/selinux/enforce")
+ else
+ # assume enforcing if you can't read it
+ SELINUX_STATE=1
+ fi
+fi
+
+selinux_fixup() {
+ if [ -n "$SELINUX_STATE" ] && [ -e "$1" ]; then
+ restorecon -R "$1"
+ fi
+}
+
+# Only read this once.
+[ -z "${cmdline}" ] && cmdline=$(cat /proc/cmdline)
+
+READONLY=
+if [ -f /etc/sysconfig/readonly-root ]; then
+ . /etc/sysconfig/readonly-root
+fi
+if strstr "$cmdline" readonlyroot ; then
+ READONLY=yes
+ [ -z "$RW_MOUNT" ] && RW_MOUNT=/var/lib/stateless/writable
+ [ -z "$STATE_MOUNT" ] && STATE_MOUNT=/var/lib/stateless/state
+fi
+if strstr "$cmdline" noreadonlyroot ; then
+ READONLY=no
+fi
+
+MOUNTS=()
+if [ "$READONLY" = "yes" -o "$TEMPORARY_STATE" = "yes" ]; then
+
+ add_mount() {
+ mnt=${1%/}
+ MOUNTS=("${MOUNTS[@]}" "$mnt")
+ }
+
+ cp_empty() {
+ if [ -e "$1" ]; then
+ echo "$1" | cpio -p -vd "$RW_MOUNT" &>/dev/null
+ add_mount $1
+ fi
+ }
+
+ cp_dirs() {
+ if [ -e "$1" ]; then
+ mkdir -p "$RW_MOUNT$1"
+ find "$1" -type d -print0 | cpio -p -0vd "$RW_MOUNT" &>/dev/null
+ add_mount $1
+ fi
+ }
+
+ cp_files() {
+ if [ -e "$1" ]; then
+ cp -a --parents "$1" "$RW_MOUNT"
+ add_mount $1
+ fi
+ }
+
+ # Common mount options for scratch space regardless of
+ # type of backing store
+ mountopts=
+
+ # Scan partitions for local scratch storage
+ rw_mount_dev=$(blkid -t LABEL="$RW_LABEL" -l -o device)
+
+ bindmountopts=
+ [ "$SLAVE_MOUNTS" = "yes" ] && bindmountopts="--make-slave"
+
+ # First try to mount scratch storage from /etc/fstab, then any
+ # partition with the proper label. If either succeeds, be sure
+ # to wipe the scratch storage clean. If both fail, then mount
+ # scratch storage via tmpfs.
+ if mount $mountopts "$RW_MOUNT" > /dev/null 2>&1 ; then
+ rm -rf "$RW_MOUNT" > /dev/null 2>&1
+ elif [ x$rw_mount_dev != x ] && mount $rw_mount_dev $mountopts "$RW_MOUNT" > /dev/null 2>&1; then
+ rm -rf "$RW_MOUNT" > /dev/null 2>&1
+ else
+ mount -n -t tmpfs $RW_OPTIONS $mountopts none "$RW_MOUNT"
+ fi
+
+ for file in /etc/rwtab /etc/rwtab.d/* /run/initramfs/rwtab ; do
+ is_ignored_file "$file" && continue
+ [ -f $file ] && while read type path ; do
+ case "$type" in
+ empty)
+ cp_empty $path
+ ;;
+ files)
+ cp_files $path
+ ;;
+ dirs)
+ cp_dirs $path
+ ;;
+ *)
+ ;;
+ esac
+ done < <(cat $file)
+ done
+
+ for m in "${MOUNTS[@]}"; do
+ prefix=0
+ for mount_point in "${MOUNTS[@]}"; do
+ [[ $m = $mount_point ]] && continue
+ if [[ $m =~ ^$mount_point/.* ]] ; then
+ prefix=1
+ break
+ fi
+ done
+ [[ $prefix -eq 1 ]] && continue
+
+ mount -n --bind $bindmountopts "$RW_MOUNT$m" "$m"
+ selinux_fixup "$m"
+ done
+
+ # Use any state passed by initramfs
+ [ -d /run/initramfs/state ] && cp -a /run/initramfs/state/* $RW_MOUNT
+
+ # In theory there should be no more than one network interface active
+ # this early in the boot process -- the one we're booting from.
+ # Use the network address to set the hostname of the client. This
+ # must be done even if we have local storage.
+ ipaddr=
+ if [ "$HOSTNAME" = "localhost" -o "$HOSTNAME" = "localhost.localdomain" ]; then
+ ipaddr=$(ip addr show to 0.0.0.0/0 scope global | awk '/[[:space:]]inet / { print gensub("/.*","","g",$2) }')
+ for ip in $ipaddr ; do
+ HOSTNAME=
+ eval $(ipcalc -h $ipaddr 2>/dev/null)
+ [ -n "$HOSTNAME" ] && { hostname ${HOSTNAME} ; break; }
+ done
+ fi
+
+ # Clients with read-only root filesystems may be provided with a
+ # place where they can place minimal amounts of persistent
+ # state. SSH keys or puppet certificates for example.
+ #
+ # Ideally we'll use puppet to manage the state directory and to
+ # create the bind mounts. However, until that's all ready this
+ # is sufficient to build a working system.
+
+ # First try to mount persistent data from /etc/fstab, then any
+ # partition with the proper label, then fallback to NFS
+ state_mount_dev=$(blkid -t LABEL="$STATE_LABEL" -l -o device)
+ if mount $mountopts $STATE_OPTIONS "$STATE_MOUNT" > /dev/null 2>&1 ; then
+ /bin/true
+ elif [ x$state_mount_dev != x ] && mount $state_mount_dev $mountopts "$STATE_MOUNT" > /dev/null 2>&1; then
+ /bin/true
+ elif [ ! -z "$CLIENTSTATE" ]; then
+ # No local storage was found. Make a final attempt to find
+ # state on an NFS server.
+
+ mount -t nfs $CLIENTSTATE/$HOSTNAME $STATE_MOUNT -o rw,nolock
+ fi
+
+ if [ -w "$STATE_MOUNT" ]; then
+
+ mount_state() {
+ if [ -e "$1" ]; then
+ [ ! -e "$STATE_MOUNT$1" ] && cp -a --parents "$1" "$STATE_MOUNT"
+ mount -n --bind $bindmountopts "$STATE_MOUNT$1" "$1"
+ fi
+ }
+
+ for file in /etc/statetab /etc/statetab.d/* ; do
+ is_ignored_file "$file" && continue
+ [ ! -f "$file" ] && continue
+
+ if [ -f "$STATE_MOUNT/$file" ] ; then
+ mount -n --bind $bindmountopts "$STATE_MOUNT/$file" "$file"
+ fi
+
+ for path in $(grep -v "^#" "$file" 2>/dev/null); do
+ mount_state "$path"
+ selinux_fixup "$path"
+ done
+ done
+
+ if [ -f "$STATE_MOUNT/files" ] ; then
+ for path in $(grep -v "^#" "$STATE_MOUNT/files" 2>/dev/null); do
+ mount_state "$path"
+ selinux_fixup "$path"
+ done
+ fi
+ fi
+
+ if mount | grep -q /var/lib/nfs/rpc_pipefs ; then
+ mount -t rpc_pipefs sunrpc /var/lib/nfs/rpc_pipefs
+ fi
+fi