clone: only update <rootfs>/etc/hostname if it exists

[mirror_lxc.git] / templates / lxc-ubuntu-cloud.in

#!/bin/bash

# template script for generating ubuntu container for LXC based on released cloud
# images
#
# Copyright © 2012 Serge Hallyn <serge.hallyn@canonical.com>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 2, as
# published by the Free Software Foundation.

# 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, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
#

set -e

if [ -r /etc/default/lxc ]; then
    . /etc/default/lxc
fi

copy_configuration()
{
    path=$1
    rootfs=$2
    name=$3
    arch=$4
    release=$5

    if [ $arch = "i386" ]; then
        arch="i686"
    fi

    # if there is exactly one veth network entry, make sure it has an
    # associated hwaddr.
    nics=`grep -e '^lxc\.network\.type[ \t]*=[ \t]*veth' $path/config | wc -l`
    if [ $nics -eq 1 ]; then
        grep -q "^lxc.network.hwaddr" $path/config || sed -i -e "/^lxc\.network\.type[ \t]*=[ \t]*veth/a lxc.network.hwaddr = 00:16:3e:$(openssl rand -hex 3| sed 's/\(..\)/\1:/g; s/.$//')" $path/config
    fi

    grep -q "^lxc.rootfs" $path/config 2>/dev/null || echo "lxc.rootfs = $rootfs" >> $path/config
    cat <<EOF >> $path/config
lxc.mount = $path/fstab
lxc.pivotdir = lxc_putold

lxc.devttydir =$ttydir
lxc.tty = 4
lxc.pts = 1024

lxc.utsname = $name
lxc.arch = $arch
lxc.cap.drop = sys_module mac_admin mac_override sys_time

# When using LXC with apparmor, uncomment the next line to run unconfined:
#lxc.aa_profile = unconfined

# To support container nesting on an Ubuntu host, uncomment next two lines:
#lxc.aa_profile = lxc-container-default-with-nesting
#lxc.hook.mount = /usr/share/lxc/hooks/mountcgroups

lxc.cgroup.devices.deny = a
# Allow any mknod (but not using the node)
lxc.cgroup.devices.allow = c *:* m
lxc.cgroup.devices.allow = b *:* m
# /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
# /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 rm
# fuse
lxc.cgroup.devices.allow = c 10:229 rwm
# tun
lxc.cgroup.devices.allow = c 10:200 rwm
# full
lxc.cgroup.devices.allow = c 1:7 rwm
# hpet
lxc.cgroup.devices.allow = c 10:228 rwm
# kvm
lxc.cgroup.devices.allow = c 10:232 rwm
EOF

    cat <<EOF > $path/fstab
proc            proc         proc    nodev,noexec,nosuid 0 0
sysfs           sys          sysfs defaults  0 0
EOF

    # rmdir /dev/shm for containers that have /run/shm
    # I'm afraid of doing rm -rf $rootfs/dev/shm, in case it did
    # get bind mounted to the host's /run/shm.  So try to rmdir
    # it, and in case that fails move it out of the way.
    if [ ! -L $rootfs/dev/shm ] && [ -d $rootfs/run/shm ] && [ -e $rootfs/dev/shm ]; then
        mv $rootfs/dev/shm $rootfs/dev/shm.bak
        ln -s /run/shm $rootfs/dev/shm
    fi

    return 0
}

usage()
{
    cat <<EOF
LXC Container configuration for Ubuntu Cloud images.

Generic Options
[ -r | --release <release> ]: Release name of container, defaults to host
[ --rootfs <path> ]: Path in which rootfs will be placed
[ -a | --arch ]: Arhcitecture of container, defaults to host arcitecture
[ -C | --cloud ]: Configure container for use with meta-data service, defaults to no
[ -T | --tarball ]: Location of tarball
[ -d | --debug ]: Run with 'set -x' to debug errors
[ -s | --stream]: Use specified stream rather than 'released'

Options, mutually exclusive of "-C" and "--cloud":
  [ -i | --hostid ]:    HostID for cloud-init, defaults to random string
  [ -u | --userdata ]:  Cloud-init user-data file to configure container on start
  [ -S | --auth-key ]:  SSH Public key file to inject into container
  [ -L | --nolocales ]: Do not copy host's locales into container

EOF
    return 0
}

options=$(getopt -o a:hp:r:n:Fi:CLS:T:ds:u: -l arch:,help,rootfs:,path:,release:,name:,flush-cache,hostid:,auth-key:,cloud,no_locales,tarball:,debug,stream:,userdata: -- "$@")
if [ $? -ne 0 ]; then
    usage $(basename $0)
    exit 1
fi
eval set -- "$options"

release=lucid
if [ -f /etc/lsb-release ]; then
    . /etc/lsb-release
    case "$DISTRIB_CODENAME" in
        lucid|natty|oneiric|precise|quantal)
            release=$DISTRIB_CODENAME
        ;;
    esac
fi

# Code taken from debootstrap
if [ -x /usr/bin/dpkg ] && /usr/bin/dpkg --print-architecture >/dev/null 2>&1; then
    arch=`/usr/bin/dpkg --print-architecture`
elif type udpkg >/dev/null 2>&1 && udpkg --print-architecture >/dev/null 2>&1; then
    arch=`/usr/bin/udpkg --print-architecture`
else
    arch=$(uname -m)
    if [ "$arch" = "i686" ]; then
        arch="i386"
    elif [ "$arch" = "x86_64" ]; then
        arch="amd64"
    elif [ "$arch" = "armv7l" ]; then
        # note: arm images don't exist before oneiric;  are called armhf in
        # precise and later;  and are not supported by the query, so we don't actually
        # support them yet (see check later on).  When Query2 is available,
        # we'll use that to enable arm images.
        arch="armhf"
    fi
fi

debug=0
hostarch=$arch
cloud=0
locales=1
flushcache=0
stream="released"
while true
do
    case "$1" in
    -h|--help)         usage $0 && exit 0;;
    -p|--path)         path=$2; shift 2;;
    -n|--name)         name=$2; shift 2;;
    -F|--flush-cache)  flushcache=1; shift 1;;
    -r|--release)      release=$2; shift 2;;
    -a|--arch)         arch=$2; shift 2;;
    -i|--hostid)       host_id=$2; shift 2;;
    -u|--userdata)     userdata=$2; shift 2;;
    -C|--cloud)        cloud=1; shift 1;;
    -S|--auth-key)     auth_key=$2; shift 2;;
    -L|--no_locales)   locales=0; shift 1;;
    -T|--tarball)      tarball=$2; shift 2;;
    -d|--debug)        debug=1; shift 1;;
    -s|--stream)       stream=$2; shift 2;;
    --rootfs)       rootfs=$2; shift 2;;
    --)                shift 1; break ;;
        *)              break ;;
    esac
done

if [ $debug -eq 1 ]; then
    set -x
fi

if [ "$arch" == "i686" ]; then
    arch=i386
fi

if [ $arch != "i386" -a $arch != "amd64" -a $arch != "armhf" -a $arch != "armel" ]; then
    echo "Only i386, amd64, armel and armhf are supported by the ubuntu cloud template."
    exit 1
fi

if [ $hostarch != "i386" -a $hostarch != "amd64" -a $hostarch != "armhf" -a $hostarch != "armel" ]; then
    echo "Only i386, amd64, armel and armhf are supported as host."
    exit 1
fi

if [ $hostarch = "amd64" -a $arch != "amd64" -a $arch != "i386" ]; then
    echo "can't create $arch container on $hostarch"
    exit 1
fi

if [ $hostarch = "i386" -a $arch != "i386" ]; then
    echo "can't create $arch container on $hostarch"
    exit 1
fi

if [ $hostarch = "armhf" -o $hostarch = "armel" ] && \
   [ $arch != "armhf" -a $arch != "armel" ]; then
    echo "can't create $arch container on $hostarch"
    exit 1
fi

if [ "$stream" != "daily" -a "$stream" != "released" ]; then
    echo "Only 'daily' and 'released' streams are supported"
    exit 1
fi

if [ -n "$userdata" ]; then
    if [ ! -f "$userdata" ]; then
        echo "Userdata ($userdata) does not exist"
        exit 1
    else
        userdata=`readlink -f $userdata`
    fi
fi

if [ -n "$auth_key" ]; then
    if [ ! -f "$auth_key" ]; then
        echo "--auth-key=${auth_key} must reference a file"
        exit 1
    fi
    auth_key=$(readlink -f "${auth_key}") ||
        { echo "failed to get full path for auth_key"; 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="$path/config"
if [ -z "$rootfs" ]; then
    if grep -q '^lxc.rootfs' $config 2>/dev/null ; then
        rootfs=`grep 'lxc.rootfs =' $config | awk -F= '{ print $2 }'`
    else
        rootfs=$path/rootfs
    fi
fi

type ubuntu-cloudimg-query
type wget

# determine the url, tarball, and directory names
# download if needed
cache="@LOCALSTATEDIR@/cache/lxc/cloud-$release"

mkdir -p $cache

if [ -n "$tarball" ]; then
    url2="$tarball"
else
    url1=`ubuntu-cloudimg-query $release $stream $arch --format "%{url}\n"`
    url2=`echo $url1 | sed -e 's/.tar.gz/-root\0/'`
fi

filename=`basename $url2`

wgetcleanup()
{
    rm -f $filename
}

buildcleanup()
{
    cd $rootfs
    umount -l $cache/$xdir || true
    rm -rf $cache
}

# if the release doesn't have a *-rootfs.tar.gz, then create one from the
# cloudimg.tar.gz by extracting the .img, mounting it loopback, and creating
# a tarball from the mounted image.
build_root_tgz()
{
    url=$1
    filename=$2

    xdir=`mktemp -d -p .`
    tarname=`basename $url`
    imgname="$release-*-cloudimg-$arch.img"
    trap buildcleanup EXIT SIGHUP SIGINT SIGTERM
    if [ $flushcache -eq 1 -o ! -f $cache/$tarname ]; then
        rm -f $tarname
        echo "Downloading cloud image from $url"
        wget $url || { echo "Couldn't find cloud image $url."; exit 1; }
    fi
    echo "Creating new cached cloud image rootfs"
    tar --wildcards -zxf $tarname $imgname
    mount -o loop $imgname $xdir
    (cd $xdir; tar zcf ../$filename .)
    umount $xdir
    rm -f $tarname $imgname
    rmdir $xdir
    echo "New cloud image cache created"
    trap EXIT
    trap SIGHUP
    trap SIGINT
    trap SIGTERM
}

mkdir -p @LOCALSTATEDIR@/lock/subsys/
(
    flock -x 200

    cd $cache
    if [ $flushcache -eq 1 ]; then
        echo "Clearing the cached images"
        rm -f $filename
    fi

    trap wgetcleanup EXIT SIGHUP SIGINT SIGTERM
    if [ ! -f $filename ]; then
        wget $url2 || build_root_tgz $url1 $filename
    fi
    trap EXIT
    trap SIGHUP
    trap SIGINT
    trap SIGTERM

    echo "Extracting container rootfs"
    mkdir -p $rootfs
    cd $rootfs
    tar -zxf $cache/$filename


    if [ $cloud -eq 0 ]; then
        echo "Configuring for running outside of a cloud environment"
        echo "If you want to configure for a cloud evironment, please use '-- -C' to create the container"

        seed_d=$rootfs/var/lib/cloud/seed/nocloud-net
        rhostid=$(uuidgen | cut -c -8)
        host_id=${hostid:-$rhostid}
        mkdir -p $seed_d

        cat > "$seed_d/meta-data" <<EOF
instance-id: lxc-$host_id
EOF
        if [ -n "$auth_key" ]; then
            {
            echo "public-keys:" &&
            sed -e '/^$/d' -e 's,^,- ,' "$auth_key" "$auth_key"
            } >> "$seed_d/meta-data"
            [ $? -eq 0 ] ||
                { echo "failed to write public keys to metadata"; exit 1; }
        fi

        rm $rootfs/etc/hostname

        if [ $locales -eq 1 ]; then
            cp /usr/lib/locale/locale-archive $rootfs/usr/lib/locale/locale-archive
        fi

        if [ -f "$userdata" ]; then
            echo "Using custom user-data"
            cp $userdata $seed_d/user-data
        else

            if [ -z "$MIRROR" ]; then
                MIRROR="http://archive.ubuntu.com/ubuntu"
            fi

            cat > "$seed_d/user-data" <<EOF
#cloud-config
output: {all: '| tee -a /var/log/cloud-init-output.log'}
apt_mirror: $MIRROR
manage_etc_hosts: localhost
locale: $(/usr/bin/locale | awk -F= '/LANG=/ {print$NF}')
password: ubuntu
chpasswd: { expire: False }
EOF
        fi
    else

        echo "Configured for running in a cloud environment."
        echo "If you do not have a meta-data service, this container will likely be useless."

    fi
) 200>@LOCALSTATEDIR@/lock/subsys/lxc-ubuntu-cloud

copy_configuration $path $rootfs $name $arch $release

echo "Container $name created."
exit 0

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