boot/firmware/ro-root.sh gelöscht
This commit is contained in:
@@ -1,120 +0,0 @@
|
|||||||
#!/bin/sh
|
|
||||||
|
|
||||||
# Read-only Root-FS for Raspian using overlayfs
|
|
||||||
# Version 1.1:
|
|
||||||
# Changed to use /proc/mounts rathern than /etc/fstab for deriving the root filesystem.
|
|
||||||
#
|
|
||||||
# Version 1:
|
|
||||||
# Created 2017 by Pascal Suter @ DALCO AG, Switzerland to work on Raspian as custom init script
|
|
||||||
# (raspbian does not use an initramfs on boot)
|
|
||||||
#
|
|
||||||
# This program is free software: you can redistribute it and/or modify
|
|
||||||
# it under the terms of the GNU General Public License as published by
|
|
||||||
# the Free Software Foundation, either version 3 of the License, or
|
|
||||||
# (at your option) any later version.
|
|
||||||
#
|
|
||||||
# This program is distributed in the hope that it will be useful,
|
|
||||||
# but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
||||||
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
||||||
# GNU General Public License for more details.
|
|
||||||
#
|
|
||||||
# You should have received a copy of the GNU General Public License
|
|
||||||
# along with this program. If not, see
|
|
||||||
# <http://www.gnu.org/licenses/>.
|
|
||||||
#
|
|
||||||
#
|
|
||||||
# Tested with Raspbian mini, 2017-01-11
|
|
||||||
#
|
|
||||||
# This script will mount the root filesystem read-only and overlay it with a temporary tempfs
|
|
||||||
# which is read-write mounted. This is done using the overlayFS which is part of the linux kernel
|
|
||||||
# since version 3.18.
|
|
||||||
# when this script is in use, all changes made to anywhere in the root filesystem mount will be lost
|
|
||||||
# upon reboot of the system. The SD card will only be accessed as read-only drive, which significantly
|
|
||||||
# helps to prolong its life and prevent filesystem coruption in environments where the system is usually
|
|
||||||
# not shut down properly
|
|
||||||
#
|
|
||||||
# Install:
|
|
||||||
# copy this script to /sbin/overlayRoot.sh and add "init=/sbin/overlayRoot.sh" to the cmdline.txt
|
|
||||||
# file in the raspbian image's boot partition.
|
|
||||||
# I strongly recommend to disable swapping before using this. it will work with swap but that just does
|
|
||||||
# not make sens as the swap file will be stored in the tempfs which again resides in the ram.
|
|
||||||
# run these commands on the booted raspberry pi BEFORE you set the init=/sbin/overlayRoot.sh boot option:
|
|
||||||
# sudo dphys-swapfile swapoff
|
|
||||||
# sudo dphys-swapfile uninstall
|
|
||||||
# sudo update-rc.d dphys-swapfile remove
|
|
||||||
#
|
|
||||||
# To install software, run upgrades and do other changes to the raspberry setup, simply remove the init=
|
|
||||||
# entry from the cmdline.txt file and reboot, make the changes, add the init= entry and reboot once more.
|
|
||||||
|
|
||||||
fail(){
|
|
||||||
echo -e "$1"
|
|
||||||
/bin/bash
|
|
||||||
}
|
|
||||||
|
|
||||||
# load module
|
|
||||||
modprobe overlay
|
|
||||||
if [ $? -ne 0 ]; then
|
|
||||||
fail "ERROR: missing overlay kernel module"
|
|
||||||
fi
|
|
||||||
# mount /proc
|
|
||||||
mount -t proc proc /proc
|
|
||||||
|
|
||||||
# create a writable fs to then create our mountpoints
|
|
||||||
mount -t tmpfs inittemp /mnt
|
|
||||||
if [ $? -ne 0 ]; then
|
|
||||||
fail "ERROR: could not create a temporary filesystem to mount the base filesystems for overlayfs"
|
|
||||||
fi
|
|
||||||
mkdir /mnt/lower
|
|
||||||
mkdir /mnt/rw
|
|
||||||
mount -t tmpfs root-rw /mnt/rw
|
|
||||||
if [ $? -ne 0 ]; then
|
|
||||||
fail "ERROR: could not create tempfs for upper filesystem"
|
|
||||||
fi
|
|
||||||
mkdir /mnt/rw/upper
|
|
||||||
mkdir /mnt/rw/work
|
|
||||||
mkdir /mnt/newroot
|
|
||||||
|
|
||||||
# mount root filesystem readonly
|
|
||||||
rootDev=`awk '$2 == "/" {print $1}' /proc/mounts`
|
|
||||||
rootMountOpt=`awk '$2 == "/" {print $4}' /proc/mounts`
|
|
||||||
rootFsType=`awk '$2 == "/" {print $3}' /proc/mounts`
|
|
||||||
mount -t ${rootFsType} -o ${rootMountOpt},ro ${rootDev} /mnt/lower
|
|
||||||
if [ $? -ne 0 ]; then
|
|
||||||
fail "ERROR: could not ro-mount original root partition"
|
|
||||||
fi
|
|
||||||
mount -t overlay -o lowerdir=/mnt/lower,upperdir=/mnt/rw/upper,workdir=/mnt/rw/work overlayfs-root /mnt/newroot
|
|
||||||
if [ $? -ne 0 ]; then
|
|
||||||
fail "ERROR: could not mount overlayFS"
|
|
||||||
fi
|
|
||||||
# create mountpoints inside the new root filesystem-overlay
|
|
||||||
mkdir /mnt/newroot/ro
|
|
||||||
mkdir /mnt/newroot/rw
|
|
||||||
# remove root mount from fstab (this is already a non-permanent modification)
|
|
||||||
grep -v "$rootDev" /mnt/lower/etc/fstab > /mnt/newroot/etc/fstab
|
|
||||||
echo "#the original root mount has been removed by overlayRoot.sh" >> /mnt/newroot/etc/fstab
|
|
||||||
echo "#this is only a temporary modification, the original fstab" >> /mnt/newroot/etc/fstab
|
|
||||||
echo "#stored on the disk can be found in /ro/etc/fstab" >> /mnt/newroot/etc/fstab
|
|
||||||
# change to the new overlay root
|
|
||||||
cd /mnt/newroot
|
|
||||||
pivot_root . mnt
|
|
||||||
exec chroot . sh -c "$(cat <<END
|
|
||||||
# move ro and rw mounts to the new root
|
|
||||||
mount --move /mnt/mnt/lower/ /ro
|
|
||||||
if [ $? -ne 0 ]; then
|
|
||||||
echo "ERROR: could not move ro-root into newroot"
|
|
||||||
/bin/bash
|
|
||||||
fi
|
|
||||||
mount --move /mnt/mnt/rw /rw
|
|
||||||
if [ $? -ne 0 ]; then
|
|
||||||
echo "ERROR: could not move tempfs rw mount into newroot"
|
|
||||||
/bin/bash
|
|
||||||
fi
|
|
||||||
# unmount unneeded mounts so we can unmout the old readonly root
|
|
||||||
umount /mnt/mnt
|
|
||||||
umount /mnt/proc
|
|
||||||
umount -l -f /mnt/dev
|
|
||||||
umount -l -f /mnt
|
|
||||||
# continue with regular init
|
|
||||||
exec /sbin/init
|
|
||||||
END
|
|
||||||
)"
|
|
||||||
Reference in New Issue
Block a user