Browse Source

Add read-only-fs.sh script

pull/4/head
Phillip Burgess 3 years ago
parent
commit
2c4e030995
1 changed files with 300 additions and 0 deletions
  1. +300
    -0
      read-only-fs.sh

+ 300
- 0
read-only-fs.sh View File

@ -0,0 +1,300 @@
#!/bin/bash
# CREDIT TO THESE TUTORIALS:
# petr.io/en/blog/2015/11/09/read-only-raspberry-pi-with-jessie
# hallard.me/raspberry-pi-read-only
# k3a.me/how-to-make-raspberrypi-truly-read-only-reliable-and-trouble-free
if [ $(id -u) -ne 0 ]; then
echo "Installer must be run as root."
echo "Try 'sudo bash $0'"
exit 1
fi
clear
echo "This script configures a Raspberry Pi"
echo "SD card to boot into read-only mode,"
echo "obviating need for clean shutdown."
echo "NO FILES ON THE CARD CAN BE CHANGED"
echo "WHEN PI IS BOOTED IN THIS STATE. Either"
echo "the filesystems must be remounted in"
echo "read/write mode, card must be mounted"
echo "R/W on another system, or an optional"
echo "jumper can be used to enable read/write"
echo "on boot."
echo
echo "Links to original tutorials are in"
echo "script source. THIS IS A ONE-WAY"
echo "OPERATION. THERE IS NO SCRIPT TO"
echo "REVERSE THIS SETUP! ALL other system"
echo "config should be complete before using"
echo "this script. MAKE A BACKUP FIRST."
echo
echo "Run time ~5 minutes. Reboot required."
echo
echo -n "CONTINUE? [y/N] "
read
if [[ ! "$REPLY" =~ ^(yes|y|Y)$ ]]; then
echo "Canceled."
exit 0
fi
# FEATURE PROMPTS ----------------------------------------------------------
# Installation doesn't begin until after all user input is taken.
INSTALL_RW_JUMPER=0
INSTALL_HALT=0
INSTALL_WATCHDOG=0
# Given a list of strings representing options, display each option
# preceded by a number (1 to N), display a prompt, check input until
# a valid number within the selection range is entered.
selectN() {
for ((i=1; i<=$#; i++)); do
echo $i. ${!i}
done
echo
REPLY=""
while :
do
echo -n "SELECT 1-$#: "
read
if [[ $REPLY -ge 1 ]] && [[ $REPLY -le $# ]]; then
return $REPLY
fi
done
}
SYS_TYPES=(Pi\ 3\ /\ Pi\ Zero\ W All\ other\ models)
WATCHDOG_MODULES=(bcm2835_wdog bcm2708_wdog)
OPTION_NAMES=(NO YES)
echo -n "Enable boot-time read/write jumper? [y/N] "
read
if [[ "$REPLY" =~ (yes|y|Y)$ ]]; then
INSTALL_RW_JUMPER=1
echo -n "GPIO pin for R/W jumper: "
read
RW_PIN=$REPLY
fi
echo -n "Install GPIO-halt utility? [y/N] "
read
if [[ "$REPLY" =~ (yes|y|Y)$ ]]; then
INSTALL_HALT=1
echo -n "GPIO pin for halt button: "
read
HALT_PIN=$REPLY
fi
echo -n "Enable kernel panic watchdog? [y/N] "
read
if [[ "$REPLY" =~ (yes|y|Y)$ ]]; then
INSTALL_WATCHDOG=1
echo "Target system type:"
selectN "${SYS_TYPES[0]}" \
"${SYS_TYPES[1]}"
WD_TARGET=$?
fi
# VERIFY SELECTIONS BEFORE CONTINUING --------------------------------------
echo
if [ $INSTALL_RW_JUMPER -eq 1 ]; then
echo "Boot-time R/W jumper: YES (GPIO$RW_PIN)"
else
echo "Boot-time R/W jumper: NO"
fi
if [ $INSTALL_HALT -eq 1 ]; then
echo "Install GPIO-halt: YES (GPIO$HALT_PIN)"
else
echo "Install GPIO-halt: NO"
fi
if [ $INSTALL_WATCHDOG -eq 1 ]; then
echo "Enable watchdog: YES (${SYS_TYPES[WD_TARGET-1]})"
else
echo "Enable watchdog: NO"
fi
echo
echo -n "CONTINUE? [y/N] "
read
if [[ ! "$REPLY" =~ ^(yes|y|Y)$ ]]; then
echo "Canceled."
exit 0
fi
# START INSTALL ------------------------------------------------------------
# All selections have been validated at this point...
# Given a filename, a regex pattern to match and a replacement string:
# Replace string if found, else no change.
# (# $1 = filename, $2 = pattern to match, $3 = replacement)
replace() {
grep $2 $1 >/dev/null
if [ $? -eq 0 ]; then
# Pattern found; replace in file
sed -i "s/$2/$3/g" $1 >/dev/null
fi
}
# Given a filename, a regex pattern to match and a replacement string:
# If found, perform replacement, else append file w/replacement on new line.
replaceAppend() {
grep $2 $1 >/dev/null
if [ $? -eq 0 ]; then
# Pattern found; replace in file
sed -i "s/$2/$3/g" $1 >/dev/null
else
# Not found; append on new line (silently)
echo $3 | sudo tee -a $1 >/dev/null
fi
}
# Given a filename, a regex pattern to match and a string:
# If found, no change, else append file with string on new line.
append1() {
grep $2 $1 >/dev/null
if [ $? -ne 0 ]; then
# Not found; append on new line (silently)
echo $3 | sudo tee -a $1 >/dev/null
fi
}
# Given a filename, a regex pattern to match and a string:
# If found, no change, else append space + string to last line --
# this is used for the single-line /boot/cmdline.txt file.
append2() {
grep $2 $1 >/dev/null
if [ $? -ne 0 ]; then
# Not found; insert in file before EOF
sed -i "s/\'/ $3/g" $1 >/dev/null
fi
}
echo
echo "Starting installation..."
echo "Updating package index files..."
apt-get update
echo "Removing unwanted packages..."
apt-get remove -y --force-yes --purge triggerhappy cron logrotate dbus \
dphys-swapfile xserver-common lightdm fake-hwclock
apt-get -y --force-yes autoremove --purge
# Replace log management with busybox (use logread if needed)
echo "Installing busybox-syslogd..."
apt-get -y --force-yes install busybox-syslogd; dpkg --purge rsyslog
echo "Configuring system..."
# Install boot-time R/W jumper test if requested
GPIOTEST="gpio -g mode $RW_PIN up\n\
if [ \`gpio -g read $RW_PIN\` -eq 0 ] ; then\n\
\tmount -o remount,rw \/\n\
\tmount -o remount,rw \/boot\n\
fi\n"
if [ $INSTALL_RW_JUMPER -ne 0 ]; then
# Check if already present in rc.local:
grep "gpio -g read" /etc/rc.local >/dev/null
if [ $? -eq 0 ]; then
# Already there, but make sure pin is correct:
sed -i "s/^.*gpio\ -g\ read.*$/$GPIOTEST/g" /etc/rc.local >/dev/null
else
# Not there, insert before final 'exit 0'
sed -i "s/^exit 0/$GPIOTEST\\nexit 0/g" /etc/rc.local >/dev/null
fi
fi
# Install watchdog if requested
if [ $INSTALL_WATCHDOG -ne 0 ]; then
apt-get install -y --force-yes watchdog
# $MODULE is specific watchdog module name
MODULE=${WATCHDOG_MODULES[($WD_TARGET-1)]}
# Add to /etc/modules, update watchdog config file
append1 /etc/modules $MODULE $MODULE
replace /etc/watchdog.conf "#watchdog-device" "watchdog-device"
replace /etc/watchdog.conf "#max-load-1" "max-load-1"
# Start watchdog at system start and start right away
insserv watchdog; /etc/init.d/watchdog start
# Additional settings needed on Jessie
append1 /lib/systemd/system/watchdog.service "WantedBy" "WantedBy=multi-user.target"
systemctl enable watchdog
# Set up automatic reboot in sysctl.conf
replaceAppend /etc/sysctl.conf "^.*kernel.panic.*$" "kernel.panic = 10"
fi
# Install gpio-halt if requested
if [ $INSTALL_HALT -ne 0 ]; then
apt-get install -y --force-yes wiringpi
echo "Installing gpio-halt in /usr/local/bin..."
cd /tmp
curl -LO https://github.com/adafruit/Adafruit-GPIO-Halt/archive/master.zip
unzip master.zip
cd Adafruit-GPIO-Halt-master
make
mv gpio-halt /usr/local/bin
cd ..
rm -rf Adafruit-GPIO-Halt-master
# Add gpio-halt to /rc.local:
grep gpio-halt /etc/rc.local >/dev/null
if [ $? -eq 0 ]; then
# gpio-halt already in rc.local, but make sure correct:
sed -i "s/^.*gpio-halt.*$/\/usr\/local\/bin\/gpio-halt $HALT_PIN \&/g" /etc/rc.local >/dev/null
else
# Insert gpio-halt into rc.local before final 'exit 0'
sed -i "s/^exit 0/\/usr\/local\/bin\/gpio-halt $HALT_PIN \&\\nexit 0/g" /etc/rc.local >/dev/null
fi
fi
# Add fastboot, noswap and/or ro to end of /boot/cmdline.txt
append2 /boot/cmdline.txt fastboot fastboot
append2 /boot/cmdline.txt noswap noswap
append2 /boot/cmdline.txt ro^o^t ro
# Move spool to /tmp
rm -rf /var/spool
ln -s /tmp /var/spool
# Make SSH work
replaceAppend /etc/ssh/sshd_config "^.*UsePrivilegeSeparation.*$" "UsePrivilegeSeparation no"
# bbro method (not working in Jessie?):
#rmdir /var/run/sshd
#ln -s /tmp /var/run/sshd
# Change spool permissions in var.conf (rondie/Margaret fix)
replace /usr/lib/tmpfiles.d/var.conf "spool\s*0755" "spool 1777"
# Move dhcpd.resolv.conf to tmpfs
touch /tmp/dhcpcd.resolv.conf
rm /etc/resolv.conf
ln -s /tmp/dhcpcd.resolv.conf /etc/resolv.conf
# Make edits to fstab
# make / ro
# tmpfs /var/log tmpfs nodev,nosuid 0 0
# tmpfs /var/tmp tmpfs nodev,nosuid 0 0
# tmpfs /tmp tmpfs nodev,nosuid 0 0
replace /etc/fstab "vfat\s*defaults\s" "vfat defaults,ro "
replace /etc/fstab "ext4\s*defaults,noatime\s" "ext4 defaults,noatime,ro "
append1 /etc/fstab "/var/log" "tmpfs /var/log tmpfs nodev,nosuid 0 0"
append1 /etc/fstab "/var/tmp" "tmpfs /var/tmp tmpfs nodev,nosuid 0 0"
append1 /etc/fstab "\s/tmp" "tmpfs /tmp tmpfs nodev,nosuid 0 0"
# PROMPT FOR REBOOT --------------------------------------------------------
echo "Done."
echo
echo "Settings take effect on next boot."
echo
echo -n "REBOOT NOW? [y/N] "
read
if [[ ! "$REPLY" =~ ^(yes|y|Y)$ ]]; then
echo "Exiting without reboot."
exit 0
fi
echo "Reboot started..."
reboot
exit 0

Loading…
Cancel
Save