qemu-debian-create-image

#!/bin/bash

clean_debian() {
	[ "$MNT_DIR" != "" ] && chroot $MNT_DIR umount /proc/ /sys/ /dev/
	sleep 1
	[ "$MNT_DIR" != "" ] && umount $MNT_DIR
	sleep 1
	[ "$DISK" != "" ] && qemu-nbd -d $DISK
	sleep 1
	[ "$MNT_DIR" != "" ] && rm -r $MNT_DIR
}

fail() {
	clean_debian
	echo ""
	echo "FAILED: $1"
	exit 1
}

cancel() {
	fail "CTRL-C detected"
}

if [ $# -lt 10 ]; then
	echo "original author: Kamil Trzcinski (https://ayufan.eu/)"
	echo "modified by: Andreas Ziegler (https://github.com/rotanid)"
	echo "license: GPL"
	echo "usage: $0 <image-file> <image-size> <hostname> <release> <ipv4 address> <ipv4 netmask> <ipv4 gateway> <ipv6 address> <ipv6 netmask> <ipv6 gateway> [optional debootstrap args]" 1>&2
	exit 1
fi

IMGFILE=$1
IMGSIZE=$2
HOSTNAME=$3
RELEASE=$4
IPADDR_V4=$5
IPMASK_V4=$6
IPGW_V4=$7
IPPTP_V4="$IPGW_V4"
IPADDR_V6=$8
IPMASK_V6=$9
IPGW_V6=${10}
shift 10

# variables
DEBPKGS="openssh-server,acpid,acpi-support-base"
DEBMIRROR="http://httpredir.debian.org/debian"

trap cancel INT

echo "Creating $IMGFILE with size $IMGSIZE..."

qemu-img create -f qcow2 $IMGFILE $IMGSIZE

echo "Installing $RELEASE into $IMGFILE..."

MNT_DIR=`mktemp -d`
DISK=

echo "Looking for nbd device..."

modprobe nbd max_part=16 || fail "failed to load nbd module into kernel"

for i in /dev/nbd* ; do
	if qemu-nbd -c $i $IMGFILE
	then
		DISK=$i
		break
	fi
done

[ "$DISK" == "" ] && fail "no nbd device available"

echo "Connected $IMGFILE to $DISK"

echo "Partitioning $DISK..."
sfdisk $DISK -q -D -uM << EOF || fail "cannot partition $IMGFILE"
,512,82
;
EOF

echo "Creating swap partition..."
mkswap ${DISK}p1 || fail "cannot create swap partition fs"

echo "Creating root partition..."
mkfs.ext4 -q ${DISK}p2 || fail "cannot create / ext4"

echo "Mounting root partition..."
mount ${DISK}p2 $MNT_DIR || fail "cannot mount /"

echo "Installing Debian $RELEASE..."
debootstrap --include=$DEBPKGS $* $RELEASE $MNT_DIR $DEBMIRROR || fail "cannot install $RELEASE into $DISK"

echo "Configuring system..."
cat <<EOF > $MNT_DIR/etc/fstab
/dev/vda2 /                   ext4    errors=remount-ro 0       1
EOF

echo $HOSTNAME > $MNT_DIR/etc/hostname

cat <<EOF > $MNT_DIR/etc/hosts
# IPv4
127.0.0.1       localhost
$IPADDR_V4	$HOSTNAME

# IPv6
::1     localhost ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters
ff02::3 ip6-allhosts
$IPADDR_V6	$HOSTNAME
EOF

cat <<EOF > $MNT_DIR/etc/network/interfaces
auto lo
iface lo inet loopback

auto eth0
iface eth0 inet static
	address $IPADDR_V4
	netmask $IPMASK_V4
	pointopoint $IPPTP_V4
	gateway	$IPGW_V4

iface eth0 inet6 static
	address $IPADDR_V6
	netmask $IPMASK_V6
	gateway $IPGW_V6
EOF

mount --bind /dev/ $MNT_DIR/dev || fail "cannot bind /dev"
chroot $MNT_DIR mount -t proc none /proc || fail "cannot mount /proc"
chroot $MNT_DIR mount -t sysfs none /sys || fail "cannot mount /sys"
LANG=C DEBIAN_FRONTEND=noninteractive chroot $MNT_DIR apt-get install -y -q linux-image-amd64 grub-pc || fail "cannot install linux-image and grub"
chroot $MNT_DIR grub-install $DISK || fail "cannot install grub"
chroot $MNT_DIR update-grub || fail "cannot update grub"

sed -i "s|${DISK}p2|/dev/vda2|g" $MNT_DIR/boot/grub/grub.cfg

read -p "Enter your ssh public key (one line!): " SSHPUBKEY
if [ ! -z "$SSHPUBKEY" ] && [[ "$SSHPUBKEY" =~ "ssh-" ]]; then
	mkdir -p $MNT_DIR/root/.ssh
	chmod 0700 $MNT_DIR/root/.ssh
	echo "$SSHPUBKEY" > $MNT_DIR/root/.ssh/authorized_keys
	chmod 0600 $MNT_DIR/root/.ssh/authorized_keys
else
	echo "you didn't provide a proper ssh pubkey, so you have to enter a password now."
	echo "please keep in mind, that passwords are less secure!"
	echo ""
	echo "Enter root password:"
	while ! chroot $MNT_DIR passwd root
	do
		echo "Try again"
	done
	echo "OK, activating password-based root-login via SSH..."
	sed -i "s|without-password|yes|" $MNT_DIR/etc/ssh/sshd_config
fi

echo "Finishing grub installation..."
grub-install $DISK --root-directory=$MNT_DIR --modules="biosdisk part_msdos" || fail "cannot reinstall grub"

echo "SUCCESS!"
clean_debian
exit 0