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@harobed
Created July 31, 2014 09:36
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#!/bin/bash
#
# lxc: linux Container library
# Authors:
# Daniel Lezcano <daniel.lezcano@free.fr>
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
# This library 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
# Lesser General Public License for more details.
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
SUITE=${SUITE:-wheezy}
MIRROR=${MIRROR:-http://cdn.debian.net/debian}
configure_debian()
{
rootfs=$1
hostname=$2
ip=$3
gateway=$4
# squeeze only has /dev/tty and /dev/tty0 by default,
# therefore creating missing device nodes for tty1-4.
for tty in $(seq 1 4); do
if [ ! -e $rootfs/dev/tty$tty ]; then
mknod $rootfs/dev/tty$tty c 4 $tty
fi
done
# configure the inittab
cat <<EOF > $rootfs/etc/inittab
id:3:initdefault:
si::sysinit:/etc/init.d/rcS
l0:0:wait:/etc/init.d/rc 0
l1:1:wait:/etc/init.d/rc 1
l2:2:wait:/etc/init.d/rc 2
l3:3:wait:/etc/init.d/rc 3
l4:4:wait:/etc/init.d/rc 4
l5:5:wait:/etc/init.d/rc 5
l6:6:wait:/etc/init.d/rc 6
# Normally not reached, but fallthrough in case of emergency.
z6:6:respawn:/sbin/sulogin
1:2345:respawn:/sbin/getty 38400 console
c1:12345:respawn:/sbin/getty 38400 tty1 linux
c2:12345:respawn:/sbin/getty 38400 tty2 linux
c3:12345:respawn:/sbin/getty 38400 tty3 linux
c4:12345:respawn:/sbin/getty 38400 tty4 linux
p6::ctrlaltdel:/sbin/init 6
p0::powerfail:/sbin/init 0
EOF
# disable selinux in debian
mkdir -p $rootfs/selinux
echo 0 > $rootfs/selinux/enforce
# configure the network using the dhcp
cat <<EOF > $rootfs/etc/network/interfaces
auto lo
iface lo inet loopback
auto veth0
iface veth0 inet static
address $ip
netmask 255.255.255.0
broadcast 10.0.255.255
gateway $gateway
dns-nameservers 8.8.8.8
dns-nameservers 8.8.4.4
EOF
# set the hostname
cat <<EOF > $rootfs/etc/hostname
$hostname
EOF
LANG="C"
# remove pointless services in a container
chroot $rootfs /usr/sbin/update-rc.d -f checkroot.sh remove
chroot $rootfs /usr/sbin/update-rc.d -f umountfs remove
chroot $rootfs /usr/sbin/update-rc.d -f hwclock.sh remove
chroot $rootfs /usr/sbin/update-rc.d -f hwclockfirst.sh remove
echo "root:root" | chroot $rootfs chpasswd
echo "Root password is 'root', please change !"
return 0
}
cleanup()
{
rm -rf $cache/partial-$SUITE-$arch
rm -rf $cache/rootfs-$SUITE-$arch
}
download_debian()
{
packages=\
ifupdown,\
locales,\
libui-dialog-perl,\
dialog,\
isc-dhcp-client,\
netbase,\
net-tools,\
iproute,\
iputils-ping,\
openssh-server,\
sudo,\
cron,\
rsyslog
cache=$1
arch=$2
trap cleanup EXIT SIGHUP SIGINT SIGTERM
# check the mini debian was not already downloaded
mkdir -p "$cache/partial-$SUITE-$arch"
if [ $? -ne 0 ]; then
echo "Failed to create '$cache/partial-$SUITE-$arch' directory"
return 1
fi
# download a mini debian into a cache
echo "Downloading debian minimal ..."
debootstrap --verbose --variant=minbase --arch=$arch \
--include=$packages \
"$SUITE" "$cache/partial-$SUITE-$arch" $MIRROR
if [ $? -ne 0 ]; then
echo "Failed to download the rootfs, aborting."
return 1
fi
mv "$1/partial-$SUITE-$arch" "$1/rootfs-$SUITE-$arch"
echo "Download complete."
trap EXIT
trap SIGINT
trap SIGTERM
trap SIGHUP
return 0
}
copy_debian()
{
cache=$1
arch=$2
rootfs=$3
# make a local copy of the minidebian
echo -n "Copying rootfs to $rootfs..."
mkdir -p $rootfs
rsync -Ha "$cache/rootfs-$SUITE-$arch"/ $rootfs/ || return 1
return 0
}
install_debian()
{
cache="@LOCALSTATEDIR@/cache/lxc/debian"
rootfs=$1
mkdir -p @LOCALSTATEDIR@/lock/subsys/
(
flock -x 200
if [ $? -ne 0 ]; then
echo "Cache repository is busy."
return 1
fi
arch=$(dpkg --print-architecture)
echo "Checking cache download in $cache/rootfs-$SUITE-$arch ... "
if [ ! -e "$cache/rootfs-$SUITE-$arch" ]; then
download_debian $cache $arch
if [ $? -ne 0 ]; then
echo "Failed to download 'debian base'"
return 1
fi
fi
copy_debian $cache $arch $rootfs
if [ $? -ne 0 ]; then
echo "Failed to copy rootfs"
return 1
fi
return 0
) 200>@LOCALSTATEDIR@/lock/subsys/lxc-debian
return $?
}
copy_configuration()
{
path=$1
rootfs=$2
hostname=$3
gateway=$4
grep -q "^lxc.rootfs" $path/config 2>/dev/null || echo "lxc.rootfs = $rootfs" >> $path/config
cat <<EOF >> $path/config
lxc.tty = 4
lxc.pts = 1024
lxc.utsname = $hostname
lxc.network.type = veth
lxc.network.name = veth0
lxc.network.flags = up
lxc.network.link = br0
lxc.network.ipv4 = $ip/24
lxc.network.ipv4.gateway = $gateway
# When using LXC with apparmor, uncomment the next line to run unconfined:
#lxc.aa_profile = unconfined
lxc.cgroup.devices.deny = a
# /dev/null and zero
lxc.cgroup.devices.allow = c 1:3 rwm
lxc.cgroup.devices.allow = c 1:5 rwm
# consoles
lxc.cgroup.devices.allow = c 5:1 rwm
lxc.cgroup.devices.allow = c 5:0 rwm
lxc.cgroup.devices.allow = c 4:0 rwm
lxc.cgroup.devices.allow = c 4:1 rwm
# /dev/{,u}random
lxc.cgroup.devices.allow = c 1:9 rwm
lxc.cgroup.devices.allow = c 1:8 rwm
lxc.cgroup.devices.allow = c 136:* rwm
lxc.cgroup.devices.allow = c 5:2 rwm
# rtc
lxc.cgroup.devices.allow = c 254:0 rwm
# mounts point
lxc.mount.entry = proc proc proc nodev,noexec,nosuid 0 0
lxc.mount.entry = sysfs sys sysfs defaults 0 0
EOF
if [ $? -ne 0 ]; then
echo "Failed to add configuration"
return 1
fi
return 0
}
clean()
{
cache="@LOCALSTATEDIR@/cache/lxc/debian"
if [ ! -e $cache ]; then
exit 0
fi
# lock, so we won't purge while someone is creating a repository
(
flock -x 200
if [ $? != 0 ]; then
echo "Cache repository is busy."
exit 1
fi
echo -n "Purging the download cache..."
rm --preserve-root --one-file-system -rf $cache && echo "Done." || exit 1
exit 0
) 200>@LOCALSTATEDIR@/lock/subsys/lxc-debian
}
usage()
{
cat <<EOF
$1 -h|--help -p|--path=<path> -i|--ip=<ip> -g|--gateway=<gateway> --clean
EOF
return 0
}
options=$(getopt -o hp:n:ci:g: -l help,path:,name:,ip:,gateway:,clean -- "$@")
if [ $? -ne 0 ]; then
usage $(basename $0)
exit 1
fi
eval set -- "$options"
while true
do
case "$1" in
-h|--help) usage $0 && exit 0;;
-p|--path) path=$2; shift 2;;
-n|--name) name=$2; shift 2;;
-i|--ip) ip=$2; shift 2;;
-g|--gateway) gateway=$2; shift 2;;
-c|--clean) clean=$2; shift 2;;
--) shift 1; break ;;
*) break ;;
esac
done
if [ ! -z "$clean" -a -z "$path" ]; then
clean || exit 1
exit 0
fi
type debootstrap
if [ $? -ne 0 ]; then
echo "'debootstrap' command is missing"
exit 1
fi
if [ -z "$path" ]; then
echo "'path' parameter is required"
exit 1
fi
if [ "$(id -u)" != "0" ]; then
echo "This script should be run as 'root'"
exit 1
fi
# detect rootfs
config="$path/config"
if grep -q '^lxc.rootfs' $config 2>/dev/null ; then
rootfs=`grep 'lxc.rootfs =' $config | awk -F= '{ print $2 }'`
else
rootfs=$path/rootfs
fi
install_debian $rootfs
if [ $? -ne 0 ]; then
echo "failed to install debian"
exit 1
fi
configure_debian $rootfs $name $ip $gateway
if [ $? -ne 0 ]; then
echo "failed to configure debian for a container"
exit 1
fi
copy_configuration $path $rootfs $name $gateway
if [ $? -ne 0 ]; then
echo "failed write configuration file"
exit 1
fi
if [ ! -z $clean ]; then
clean || exit 1
exit 0
fi
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