make-lfs-iso

#!/bin/bash -e

#*** CHANGE THIS VARIABLE EVERY TIME THE CLASS IS OFFERED ***
#This variable holds the name of the current release of the LFS book. The book
#will be installed on the CD for offline reading by the students.
export BOOK_ZIP='LFS-BOOK-7.4.tar.bz2'

#*** CHANGE THIS VARIABLE EVERY TIME THE CLASS IS OFFERED ***
#These are extra packages that make using the USB far
#easier. It also include the list of packages found in
#the LFS "Host System Requirements" section in the preface.
#Many of these are installed by default they are listed
#here for clarity. This leaves out *glibc* and the *kernel*
#because they are part of the base install and have no
#separate pacakges.
export EXTRAS='lxde-common lxterminal lxsession lxappearance lxrandr lxtask \
               xorg tango-icon-theme iceweasel slim \
               squashfs-tools build-essential bootcd syslinux network-manager \
               bash binutils bison bzip2 coreutils diffutils findutils \
               gawk gcc grep gzip m4 make patch perl sed tar texinfo \
               xz-utils'

#This variable sets where the initial system files will be temporarily
#installed
export CHROOT='/media/chroot'

#This variable sets a directory that will temporarily hold the ISO system
#just before the file is built.
export ISO_BUILD='/media/iso'

#This is the final location for the ISO file
export ISO="$PWD/lfs-cd.iso"

#This variable sets the location of the default files directory which
#holds settings files for the new system. It is set relative to the
#directory containing this script.
export DEFFILES='def-files'

#This should be the architecture the new system
export ARCH='i386'

#The Ubuntu "code name" to use for setting up apt (leave it as is)
export CODE_NAME='saucy'

#The mirror to use for fetching the initial system files and for apt to use
#when installing packages
export MIRROR='http://archive.ubuntu.com/ubuntu'

#This mirror host security updates
export SEC_MIRROR="${MIRROR/archive/security}"

#This is the package name for the kernel the LiveCD will use
export KERNEL="linux-image-generic"

#These are the header files for the above kernel
export HEADERS="$(echo $KERNEL | sed 's/image/headers/')"

export LOG="$PWD/lfs-cd.log"
if [ -f $LOG ] ; then rm -f $LOG ; fi

#This function displays information messages using a green font.
#param: The message to display.
#usage: info "This is some information"
function info {
    echo -e "\033[1;32m$@\033[0;49m"
    echo "INFO:    $@" >> $LOG
}

#This function displays warnings in a yellow font.
#param: The message to display.
#usage: warn "This is a warning"
function warn {
    echo -e "\033[1;33mWARNING: $@\033[0;49m"
    echo "WARNING: $@" >> $LOG
}

#This function is used to cleanly exit the script. It does this by unmounting
#all devices, displaying a given error message, and exiting with an error
#code.
#param: The error message to display.
#usage: die "This is an error"
function error_exit {
    unmount_all

    #Create the line of asterisks
    stars=$( printf '%0.1s' "*"{1..75} )

    printf "\n\033[1;31m$stars\n\n"

    #Print out message, limit the line length to 70 chars
    echo -e "$@" | fold -s -w 70
    echo "DIE:     $@" >> $LOG

    printf "\n$stars\033[0;49m\n"
    exit 1
}

#Trap the killer signals so that we can exit with a good message
trap "error_exit 'Received signal SIGHUP, exiting.'" SIGHUP
trap "error_exit 'Received signal SIGINT, exiting.'" SIGINT
trap "error_exit 'Received signal SIGTERM, exiting.'" SIGTERM

#Alias the function so that it will print a message with the following format:
#prog-name(@line#): message
#We have to explicitly allow aliases, we do this because they make calling the
#function much easier (see example)
shopt -s expand_aliases
alias die='error_exit "Error ${0}(@`echo $(( $LINENO - 1 ))`):"'

#This function checks that a given device or path is mounted, and if the
#parameter is, this function then unmounts it.
#param: A mount point or device file
#usage: unmount /some/directory
function unmount {
    if grep -q $1 /etc/mtab ; then
        if ! umount -v -f $1 ; then
            warn "Failed to unmount $1, trying last resort unmount"
            #Try lazy unmounting as a last resort
            if ! umount -v -l $1 ; then
                warn "Failed to unmount $1!"
            else
                warn "Lazy unmounted $1"
            fi
        else
            info "Unmounted $1"
        fi
    else
        info "$1 is not mounted"
    fi
}

#This function unmounts all the mount-points created in this script.
#It is used to clean-up at the end or after an error occurs. This
#function does not check "devices" it instead calls the unmount
#function using mount points.
function unmount_all {
    unmount $CHROOT/sys
    unmount $CHROOT/proc
    unmount $CHROOT/dev/pts
    unmount $CHROOT/dev
    unmount $CHROOT/tmp

    if [[ ! -z "$MNT" ]] ; then
        unmount "$MNT"
        rmdir -v "$MNT" #MNT is a mktemp directory so get rid of it
    fi
}

#See if we are the root user
if [[ "$UID" != "0" ]] ; then
    die 'This script can only be run as root'
fi

#Set the build mode
BUILD="iso"

info "Will build the iso file: $ISO"

#Change the DEFFILES variable to an absolute directory
export DEFFILES="$(cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd)/$DEFFILES"
if [[ ! -d $DEFFILES ]] ; then
    die "The $DEFFILES directory does not exist, try changing the configuration value at the top of the script."
else
    info "Will look for default files in $DEFFILES"
fi

if false ; then #DEBUG

#Make sure the mkisofs program is available so we can create the ISO file
if ! which mkisofs > /dev/null ; then
    warn "The mkisofs program is not installed, installing it..."
    if ! apt-get install -y genisoimage ; then
        die "Could not install the genisoimage package (to get mkisofs)"
    fi
fi

#Clear out the ISO build directory if it exists
if [[ -e "$ISO_BUILD" ]] ; then
    info "Removing old ISO build directory"
    rm -rf "$ISO_BUILD"
fi

info "Checking that the main apt mirror is working"
if ! wget "$MIRROR" -O /dev/null ; then
    die "The mirror $MIRROR appears to be down or invalid"
else
    info "Apt mirror is working"
fi

info "Checking the security updates mirror is working"
if ! wget "$SEC_MIRROR" -O /dev/null ; then
    die "The mirror $SEC_MIRROR appears to be down or invalid"
else
    info "Security mirror is working"
fi

info "Unmounting pseudo-filesystems if they are mounted from previous attempt"
unmount_all

#If the $CHROOT directory exits, destroy it so we have a clean slate.
if [ -d $CHROOT ] ; then
    info "Clearing $CHROOT for a clean slate ..."
    if ! rm -rf "$CHROOT" ; then
        die "Could not remove the directory"
    fi
fi

info "Creating the $CHROOT directory"
if ! mkdir -p "$CHROOT" ; then
    die "Could not create the chroot directory at $CHROOT"
fi

#This program creates a minimal linux system
if [ ! -f /usr/sbin/debootstrap ] ; then
    warn "Installing deboostrap so we can create a minimal system"
    if ! apt-get -y install debootstrap ; then
        die "Could not install debootstrap"
    fi
fi

#Syslinux is going to be the boot loader, make sure it is available
if [ ! -e /usr/lib/syslinux/isolinux.bin ] ; then
    warn "The syslinux package is not installed, installing it..."
    if ! apt-get -y install syslinux; then
        die "Could not install the syslinux package"
    fi
fi

#Extlinux is the boot loader for USB installs
if ! which extlinux > /dev/null ; then
    warn "The extlinux package is not installed, installing it..."
    if ! apt-get -y install extlinux; then
        die "Could not install the extlinux package"
    fi
fi

info 'Bootstrapping in a basic system'
if ! /usr/sbin/debootstrap --arch "$ARCH" "$CODE_NAME" "$CHROOT" "$MIRROR" ; then
    die 'Failed to bootstrap'
fi

#Copy the timezone info from the system to the new USB drive
if ! cp /etc/timezone "$CHROOT/etc/timezone" ; then
    die 'Failed to update the /etc/timezone file'
fi

#Set some important networking configuration files
info "Set $CHROOT/etc/hostname"
HOST="usb"
if ! echo -n $HOST > $CHROOT/etc/hostname ; then
    die "Failed to update the /etc/hostname file"
fi

if ! echo "127.0.0.1 localhost $HOST" > $CHROOT/etc/hosts ; then
    die 'Failed to create the /etc/hosts file'
fi

info 'Creating the sources.list file for apt'
cat >$CHROOT/etc/apt/sources.list  <<EOF

deb $MIRROR ${CODE_NAME} main restricted universe multiverse
deb $SEC_MIRROR ${CODE_NAME}-security main restricted universe multiverse
EOF

if [[ ! -e $CHROOT/etc/apt/sources.list ]] ; then
    die "Failed to create $CHROOT/etc/apt/sources.list file"
fi

info "Installing root's bashrc file"
if ! sed "s|HTTP_CLIENT_SCRIPT|$HTTP_CLIENT_SCRIPT|" \
       $DEFFILES/bashrc > $CHROOT/root/.bashrc ; then
    die "Could not install the bashrc file"

#Double check sed worked correctly
elif ! grep -q "$HTTP_CLIENT_SCRIPT" $CHROOT/root/.bashrc ; then
    die "Failed to add the mirror \"$HTTP_CLIENT_SCRIPT\" to the bashrc script"
fi

info "Mounting the needed directories under $CHROOT"
if ! (mount -v --bind /dev $CHROOT/dev &&
      mount -vt devpts devpts $CHROOT/dev/pts -o gid=5,mode=620 &&
      mount -vt proc proc $CHROOT/proc &&
      mount -vt sysfs sysfs $CHROOT/sys &&
      mount -vt tmpfs tmpfs $CHROOT/tmp ) ; then
    die 'A mount failed!'
fi

fi #DEBUG

info "Copying over needed files from $DEFFILES"
if ! cp -v $DEFFILES/fstab $CHROOT/etc/fstab ; then
    die "Failed to create $CHROOT/etc/fstab file"
elif ! cp -v $DEFFILES/kernel-img.conf $CHROOT/etc/kernel-img.conf ; then
    die "Failed to copy the $CHROOT/etc/kernel-img.conf file"
elif ! cp -v $DEFFILES/vimrc $CHROOT/root/.vimrc ; then
    die "Failed to copy the $CHROOT/root/.vimrc file"
elif ! cp $CHROOT/root/.vimrc $CHROOT/etc/skel/ ; then
    die "Failed to copy the .vimrc file to $CHROOT/etc/skel"
elif ! cp -v $DEFFILES/preselects $CHROOT/root/conf ; then
    die "Failed to copy the pre-selections file."
fi

info 'Creating an installer script for chroot'
if ! cat > $CHROOT/chroot-install <<EOF
#!/bin/bash -e

function info {
    echo -e "\033[1;34m\$@\033[0;49m"
}

function die {
    echo -e "\n\033[1;31m\$@\033[0;49m"
    exit 128
}

info "Beginning chroot install"

#Unmount the directories when exiting out
trap "{ umount -lv /proc /sys /tmp /dev; exit 255 }" SIGINT SIGTERM

info "Setting local time"
ln -svf /usr/share/zoneinfo/US/Central /etc/localtime

info 'Setting up the root user'
if grep -q admin /etc/group ; then
    sed -i '/^admin.*$/d' /etc/group
fi
groupadd admin
usermod -a -G 'users,plugdev,audio,cdrom,admin,disk' root
passwd -d root #Make root have no password

info 'Preseeding for apt'
if ! debconf-set-selections /root/conf ; then
    die "Failed to preseed apt"
fi

rm -v /root/conf

#export DEBIAN_FRONTEND=noninteractive

apt-get clean
apt-get update || apt-get update

if ! apt-get -y --no-install-recommends install $KERNEL ; then
    die "Failed to install the kernel"
fi

if ! apt-get -y install $HEADERS dhcpcd squashfs-tools  \
                   dialog mingetty vim-nox wget jfsutils \
                   parted gpm laptop-detect debootstrap less  \
                   initramfs-tools live-boot locales \
                   debconf-utils hicolor-icon-theme $EXTRAS ; then
    die "Failed to install all of the required software"
fi

#Try installing Virtualbox's Guest additions in case
#we use the system in a VM
info "Installing Virtualbox's Guest Additions"
wget -q http://download.virtualbox.org/virtualbox/debian/oracle_vbox.asc -O- | sudo apt-key add - && apt-get update && apt-get -y install virtualbox-guest-utils

info "Updating the system"
apt-get -y dist-upgrade && apt-get -y autoremove

info "Cleaning up after apt"
apt-get -y clean

#Force a black listing of the old pc-speaker driver
echo blacklist snd-pcsp >> /etc/modprobe.d/blacklist.conf

info Fixing sudoers file
if ! cp -v /etc/sudoers /tmp/sudoers.tmp ; then
    die 'Could not copy sudoers to begin no password change'
elif ! sed -i 's/^%admin.*$/%admin ALL=NOPASSWD:ALL/' /tmp/sudoers.tmp ; then
    die 'Could not replace ALL with NOPASSWD field in admin.'
elif ! sed -i 's/^%sudo.*$/%sudo ALL=NOPASSWD:ALL/' /tmp/sudoers.tmp ; then
    die 'Could not replace ALL with NOPASSWD field in sudoers.'
elif ! mv -v /tmp/sudoers.tmp /etc/sudoers ; then
    die 'Could not replace sudoers file with new one.'
fi

info "Making root own /root"
chown -R root:root /root

info "Fixing the path"


#Make mingetty auto-login on tty1
sed 's|^exec.*$|exec /sbin/mingetty --autologin root --noclear tty1|' -i /etc/init/tty1.conf

info "Finished chroot script sucessfully"
exit 0
EOF
then
    die "Could not create the script that manages the chroot install."
fi

#Make the install script executable
if ! chmod u+x $CHROOT/chroot-install ; then
    die "Could not make the chroot install script executable."
fi

info 'Performing chroot install ...'
if ! LANG=C chroot $CHROOT /chroot-install ; then
    die "Chroot install failed!"
fi

#For some reason the chroot changes the host environment's hostname
#value. This is to change it back.
info "Fixing host's hostname"
if ! hostname $( cat /etc/hostname ) ; then
    warn "Could not fix host environment's hostname"
fi

#Cleanup the install script
if ! rm $CHROOT/chroot-install ; then
    warn "Failed to remove the chroot-install script"
fi

info 'Setting up the defults for the LXDE desktop'
if [ ! -d "$CHROOT/root/.config" ] ; then
    if ! mkdir -vp "$CHROOT/root/.config" ; then
        die "Failed to make the desktop setup directory $CHROOT/root/.config"
    fi
fi

if ! tar xf "$DEFFILES/lxconfig.tar.bz2" -C "$CHROOT/root/.config" ; then
    die "Could not install the desktop configuration files"
fi

info Setting slim to auto-login
cat >> $CHROOT/etc/slim.conf <<EOF
default_user        root
auto_login          yes
EOF

#Switch the the root user's desktop to make things easier
if [ ! -d $CHROOT/root/Desktop ] ; then
    mkdir -p $CHROOT/root/Desktop
fi

pushd $CHROOT/root/Desktop > /dev/null

if [ -d './LFS' ] ; then
    rm -rf './LFS'
fi

info 'Downloading and installing the LFS book for off line reading.'
if ! wget "http://www.linuxfromscratch.org/lfs/downloads/stable/$BOOK_ZIP" ;
then
    die 'Failed to download the LFS book'
fi

if ! tar xf "$BOOK_ZIP";  then
    die 'Failed to unarchive the book file'
fi

if ! rm -vf "$BOOK_ZIP" ; then
    warn "Could not remove the $BOOK_ZIP file."
fi

if ! mv "$(find . -maxdepth 1 -type d | tail -n 1)" "LFS" ; then
    warn 'Failed to rename the unzipped book directory to LFS'
fi

info "Creating a webpage that redirects to the class' Notes website"
if ! cp -v "$DEFFILES/notes.html" "Class Notes.html" ; then
    die "Could not place the Class Notes.html file on the desktop"
fi

#Return to the original directory
popd > /dev/null

#udev is attached to *this* machine's network card now.
#Get rid of this rule to make udev think it is a brand new install
info 'Fixing udev network card rules'
if [ -e /media/chroot/etc/udev/rules.d/70-persistent-net.rules ] && \
     ! rm /media/chroot/etc/udev/rules.d/70-persistent-net.rules ; then
    warn "Could not fix network card udev rules"
fi

#By default the interfaces file has allow-hotplug instead of
#the auto keyword. The allow-hotplug won't allow the network
#card to start. We need the interfaces file to be modified
#before ifup is executed. So we will rewrite part of the
#networking startup script to fix the interfaces file
#just before ifup is executed.
info "Fixing network startup script"
awk "
/ifup -a/ {
    print \"\tsed 's/allow-hotplug/auto/' /etc/network/interfaces > /tmp/interfaces\" ;
    print \"\tmv /tmp/interfaces  /etc/network/interfaces\"
}

{print \$0}" "$CHROOT/etc/init.d/networking" > /tmp/networking
mv -v "/tmp/networking" "$CHROOT/etc/init.d/networking"
chmod -v 755 "$CHROOT/etc/init.d/networking"

#We will shrink the size of the ISO by zeroing out documentation
#and log files.
info 'Discovering what files to zero out...'
if ! (find $CHROOT/usr/share/doc -type f -size +1b > /tmp/commit_zerosize   &&
      find $CHROOT/usr/share/man -type f -size +1b >> /tmp/commit_zerosize  &&
      find $CHROOT/usr/share/info -type f -size +1b >> /tmp/commit_zerosize &&
      find $CHROOT/var/log -type f -size +1b >> /tmp/commit_zerosize  ) ; then
    die "Could not find files to zero out"
fi

info 'Making the man, doc, and info files have zero size ...'
NFILES="$(wc -l /tmp/commit_zerosize | awk '{ print $1 }')"
i=1
cat /tmp/commit_zerosize | while read file ; do
    echo -n -e "\tZeroing $i/$NFILES files\r"
    rm $file
    touch $file
    i=$[i + 1]
done ; echo

#Get rid of any left over deb files to further reduce the ISO size
info 'Getting rid of any left over deb files'
rm -rf $CHROOT/var/cache/apt/archives/*

info "Creating the root user's Desktop directory"
if [ ! -d "$CHROOT/root/Desktop" ] ; then
    mkdir "$CHROOT/root/Desktop"
fi

#Tell squashfs not to include these files or directories
info 'Creating directory-exclusion file'
if ! cp -v "$DEFFILES/exclude" "$CHROOT/tmp/exclude" ; then
    die 'Could not install the squashfs exclusion file'
fi

info 'Creating the file system file.'
if ! chroot "$CHROOT" /usr/bin/mksquashfs / /filesystem.squashfs -noappend -always-use-fragments -wildcards -ef /tmp/exclude -processors 4; then
    die "Failed to squash the file system."
fi

#fi #DEBUG
##########################################################################
#
# Create ISO Image File
#
##########################################################################
info "Creating directories for the ISO image."
if ! mkdir -pv "$ISO_BUILD"/{isolinux,live,boot} ; then
    die "Could not create directories for ISO filesystem at $ISO_BUILD"
fi

info "Installing $ISO files for booting"
if ! cp -v "$CHROOT/filesystem.squashfs" "$ISO_BUILD/live/" ; then
    die "Could not copy the filesystem.squashfs file to the CD."
elif ! cp -vR "$CHROOT/boot" "$ISO_BUILD/" ; then
    die "Could not copy the boot directory."
fi

#Install the boot loader
info 'Installing the bootloader files'
if ! cp -v /usr/lib/syslinux/isolinux.bin "$ISO_BUILD/isolinux" ; then
    die "Could not install the isolinux bootloader"
fi

#mkisofs borks file names with hyphens, it silently changes them to
#underscore characters. We have to take this into account below.
#That is the reason for the sed pipeline in this config file.
info "Creating the isolinux configuration file"
pushd $CHROOT > /dev/null

info "Install the isolinux.cfg file"
if ! cp -v "$DEFFILES/isolinux.cfg" "$ISO_BUILD/isolinux/isolinux.cfg" ; then
    die "Could not install the boot loader configuration file"
fi

info "Puting actual file names in isolinux.cfg"
sed -i -e "s/vmlinuz/$(basename $ISO_BUILD/boot/vmlinuz* | tr - _)/" \
       -e "s/initrd/$(basename $ISO_BUILD/boot/initrd* | tr - _)/" \
       "$ISO_BUILD/isolinux/isolinux.cfg"



ISOTMP="$(dirname $ISO)/temp-$(basename $ISO)"
info "Creating the iso file $ISOTMP"
if mkisofs -o "$ISOTMP" -allow-multidot \
      -l -b isolinux/isolinux.bin -c isolinux/boot.cat \
      -no-emul-boot -boot-load-size 4 -boot-info-table \
      "$ISO_BUILD" ; then
    info "Created the ISO file"
else
    die "Failed to create the ISO file"
fi

info "Installing ISO at the final location"
mv -v "$ISOTMP" "$ISO"

info 'Installation Finished Successfully!!!'
info "ISO file $ISO"