templates/lxc-ubuntu-cloud.in

   1 #!/bin/bash
   2
   3 # template script for generating ubuntu container for LXC based on released
   4 # cloud images.
   5 #
   6 # Copyright © 2012 Serge Hallyn <serge.hallyn@canonical.com>
   7 #
   8 #  This library is free software; you can redistribute it and/or
   9 #  modify it under the terms of the GNU Lesser General Public
  10 #  License as published by the Free Software Foundation; either
  11 #  version 2.1 of the License, or (at your option) any later version.
  12
  13 #  This library is distributed in the hope that it will be useful,
  14 #  but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 #  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16 #  Lesser General Public License for more details.
  17
  18 #  You should have received a copy of the GNU Lesser General Public
  19 #  License along with this library; if not, write to the Free Software
  20 #  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  21
  22 set -e
  23
  24 STATE_DIR="@LOCALSTATEDIR@"
  25 HOOK_DIR="@LXCHOOKDIR@"
  26 CLONE_HOOK_FN="$HOOK_DIR/ubuntu-cloud-prep"
  27 LXC_TEMPLATE_CONFIG="@LXCTEMPLATECONFIG@"
  28
  29 if [ -r /etc/default/lxc ]; then
  30     . /etc/default/lxc
  31 fi
  32
  33 am_in_userns() {
  34     [ -e /proc/self/uid_map ] || { echo no; return; }
  35     [ "$(wc -l /proc/self/uid_map | awk '{ print $1 }')" -eq 1 ] || { echo yes; return; }
  36     line=$(awk '{ print $1 " " $2 " " $3 }' /proc/self/uid_map)
  37     [ "$line" = "0 0 4294967295" ] && { echo no; return; }
  38     echo yes
  39 }
  40
  41 in_userns=0
  42 [ $(am_in_userns) = "yes" ] && in_userns=1
  43
  44 copy_configuration()
  45 {
  46     path=$1
  47     rootfs=$2
  48     name=$3
  49     arch=$4
  50     release=$5
  51
  52     if [ $arch = "i386" ]; then
  53         arch="i686"
  54     fi
  55
  56     # if there is exactly one veth network entry, make sure it has an
  57     # associated hwaddr.
  58     nics=`grep -e '^lxc\.network\.type[ \t]*=[ \t]*veth' $path/config | wc -l`
  59     if [ $nics -eq 1 ]; then
  60         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
  61     fi
  62
  63     # Generate the configuration file
  64     ## Create the fstab (empty by default)
  65     touch $path/fstab
  66
  67     ## Relocate all the network config entries
  68     sed -i -e "/lxc.network/{w ${path}/config-network" -e "d}" $path/config
  69
  70     ## Relocate any other config entries
  71     sed -i -e "/lxc./{w ${path}/config-auto" -e "d}" $path/config
  72
  73     ## Add all the includes
  74     echo "" >> $path/config
  75     echo "# Common configuration" >> $path/config
  76     if [ -e "${LXC_TEMPLATE_CONFIG}/ubuntu-cloud.common.conf" ]; then
  77         echo "lxc.include = ${LXC_TEMPLATE_CONFIG}/ubuntu-cloud.common.conf" >> $path/config
  78     fi
  79     if [ -e "${LXC_TEMPLATE_CONFIG}/ubuntu-cloud.${release}.conf" ]; then
  80         echo "lxc.include = ${LXC_TEMPLATE_CONFIG}/ubuntu-cloud.${release}.conf" >> $path/config
  81     fi
  82     if [ $in_userns -eq 1 ] && [ -e "${LXC_TEMPLATE_CONFIG}/ubuntu-cloud.userns.conf" ]; then
  83         echo "lxc.include = ${LXC_TEMPLATE_CONFIG}/ubuntu-cloud.userns.conf" >> $path/config
  84     fi
  85
  86     ## Add the container-specific config
  87     echo "" >> $path/config
  88     echo "# Container specific configuration" >> $path/config
  89     [ -e "$path/config-auto" ] && cat $path/config-auto >> $path/config && rm $path/config-auto
  90     grep -q "^lxc.rootfs" $path/config 2>/dev/null || echo "lxc.rootfs = $rootfs" >> $path/config
  91     cat <<EOF >> $path/config
  92 lxc.mount = $path/fstab
  93 lxc.utsname = $name
  94 lxc.arch = $arch
  95 EOF
  96
  97     ## Re-add the previously removed network config
  98     echo "" >> $path/config
  99     echo "# Network configuration" >> $path/config
 100     cat $path/config-network >> $path/config
 101     rm $path/config-network
 102
 103     # Set initial timezone as on host
 104     if [ -f /etc/timezone ]; then
 105         cat /etc/timezone > $rootfs/etc/timezone
 106         chroot $rootfs dpkg-reconfigure -f noninteractive tzdata
 107     elif [ -f /etc/sysconfig/clock ]; then
 108         source /etc/sysconfig/clock
 109         echo $ZONE > $rootfs/etc/timezone
 110         chroot $rootfs dpkg-reconfigure -f noninteractive tzdata
 111     else
 112         echo "Timezone in container is not configured. Adjust it manually."
 113     fi
 114
 115     # rmdir /dev/shm for containers that have /run/shm
 116     # I'm afraid of doing rm -rf $rootfs/dev/shm, in case it did
 117     # get bind mounted to the host's /run/shm.  So try to rmdir
 118     # it, and in case that fails move it out of the way.
 119     # NOTE: This can only be removed once 12.04 goes out of support
 120     if [ ! -L $rootfs/dev/shm ] && [ -d $rootfs/run/shm ] && [ -e $rootfs/dev/shm ]; then
 121         rmdir $rootfs/dev/shm 2>/dev/null || mv $rootfs/dev/shm $rootfs/dev/shm.bak
 122         ln -s /run/shm $rootfs/dev/shm
 123     fi
 124
 125     return 0
 126 }
 127
 128 usage()
 129 {
 130     cat <<EOF
 131 LXC Container configuration for Ubuntu Cloud images.
 132
 133 Generic Options
 134 [ -r | --release <release> ]: Release name of container, defaults to host
 135 [ --rootfs <path> ]: Path in which rootfs will be placed
 136 [ -a | --arch ]: Arhcitecture of container, defaults to host architecture
 137 [ -T | --tarball ]: Location of tarball
 138 [ -d | --debug ]: Run with 'set -x' to debug errors
 139 [ -s | --stream]: Use specified stream rather than 'released'
 140
 141 Additionally, clone hooks can be passed through (ie, --userdata).  For those,
 142 see:
 143   $CLONE_HOOK_FN --help
 144 EOF
 145     return 0
 146 }
 147
 148 options=$(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:,mapped-uid: -- "$@")
 149 if [ $? -ne 0 ]; then
 150     usage $(basename $0)
 151     exit 1
 152 fi
 153 eval set -- "$options"
 154
 155 mapped_uid=-1
 156 # default release is precise, or the systems release if recognized
 157 release=precise
 158 if [ -f /etc/lsb-release ]; then
 159     . /etc/lsb-release
 160     rels=$(ubuntu-distro-info --supported 2>/dev/null) ||
 161         rels="lucid natty oneiric precise quantal raring saucy"
 162     for r in $rels; do
 163         [ "$DISTRIB_CODENAME" = "$r" ] && release="$r"
 164     done
 165 fi
 166
 167 # Code taken from debootstrap
 168 if [ -x /usr/bin/dpkg ] && /usr/bin/dpkg --print-architecture >/dev/null 2>&1; then
 169     arch=`/usr/bin/dpkg --print-architecture`
 170 elif type udpkg >/dev/null 2>&1 && udpkg --print-architecture >/dev/null 2>&1; then
 171     arch=`/usr/bin/udpkg --print-architecture`
 172 else
 173     arch=$(uname -m)
 174     if [ "$arch" = "i686" ]; then
 175         arch="i386"
 176     elif [ "$arch" = "x86_64" ]; then
 177         arch="amd64"
 178     elif [ "$arch" = "armv7l" ]; then
 179         # note: arm images don't exist before oneiric;  are called armhf in
 180         # precise and later;  and are not supported by the query, so we don't actually
 181         # support them yet (see check later on).  When Query2 is available,
 182         # we'll use that to enable arm images.
 183         arch="armhf"
 184     fi
 185 fi
 186
 187 debug=0
 188 hostarch=$arch
 189 cloud=0
 190 locales=1
 191 flushcache=0
 192 stream="released"
 193 cloneargs=()
 194 while true
 195 do
 196     case "$1" in
 197     -h|--help)         usage $0 && exit 0;;
 198     -p|--path)         path=$2; shift 2;;
 199     -n|--name)         name=$2; shift 2;;
 200     -F|--flush-cache)  flushcache=1; shift 1;;
 201     -r|--release)      release=$2; shift 2;;
 202     -a|--arch)         arch=$2; shift 2;;
 203     -T|--tarball)      tarball=$2; shift 2;;
 204     -d|--debug)        debug=1; shift 1;;
 205     -s|--stream)       stream=$2; shift 2;;
 206     --rootfs)          rootfs=$2; shift 2;;
 207     -L|--no?locales)   cloneargs[${#cloneargs[@]}]="--no-locales"; shift 1;;
 208     -i|--hostid)       cloneargs[${#cloneargs[@]}]="--hostid=$2"; shift 2;;
 209     -u|--userdata)     cloneargs[${#cloneargs[@]}]="--userdata=$2"; shift 2;;
 210     -C|--cloud)        cloneargs[${#cloneargs[@]}]="--cloud"; shift 1;;
 211     -S|--auth-key)     cloneargs[${#cloneargs[@]}]="--auth-key=$2"; shift 2;;
 212     --mapped-uid)      mapped_uid=$2; shift 2;;
 213     --)                shift 1; break ;;
 214         *)              break ;;
 215     esac
 216 done
 217
 218 echo "mapped_uid is .$mapped_uid."
 219 cloneargs=( "--name=$name" "${cloneargs[@]}" )
 220
 221 if [ $debug -eq 1 ]; then
 222     set -x
 223 fi
 224
 225 if [ "$arch" == "i686" ]; then
 226     arch=i386
 227 fi
 228
 229 if [ $arch != "i386" -a $arch != "amd64" -a $arch != "armhf" -a $arch != "armel" ]; then
 230     echo "Only i386, amd64, armel and armhf are supported by the ubuntu cloud template."
 231     exit 1
 232 fi
 233
 234 if [ $hostarch != "i386" -a $hostarch != "amd64" -a $hostarch != "armhf" -a $hostarch != "armel" ]; then
 235     echo "Only i386, amd64, armel and armhf are supported as host."
 236     exit 1
 237 fi
 238
 239 if [ $hostarch = "amd64" -a $arch != "amd64" -a $arch != "i386" ]; then
 240     echo "can't create $arch container on $hostarch"
 241     exit 1
 242 fi
 243
 244 if [ $hostarch = "i386" -a $arch != "i386" ]; then
 245     echo "can't create $arch container on $hostarch"
 246     exit 1
 247 fi
 248
 249 if [ $hostarch = "armhf" -o $hostarch = "armel" ] && \
 250    [ $arch != "armhf" -a $arch != "armel" ]; then
 251     echo "can't create $arch container on $hostarch"
 252     exit 1
 253 fi
 254
 255 if [ "$stream" != "daily" -a "$stream" != "released" ]; then
 256     echo "Only 'daily' and 'released' streams are supported"
 257     exit 1
 258 fi
 259
 260 if [ -z "$path" ]; then
 261     echo "'path' parameter is required"
 262     exit 1
 263 fi
 264
 265 if [ "$(id -u)" != "0" ]; then
 266     echo "This script should be run as 'root'"
 267     exit 1
 268 fi
 269
 270 # detect rootfs
 271 config="$path/config"
 272 if [ -z "$rootfs" ]; then
 273     if grep -q '^lxc.rootfs' $config 2>/dev/null ; then
 274         rootfs=$(awk -F= '/^lxc.rootfs =/{ print $2 }' $config)
 275     else
 276         rootfs=$path/rootfs
 277     fi
 278 fi
 279
 280 type ubuntu-cloudimg-query
 281 type wget
 282
 283 # determine the url, tarball, and directory names
 284 # download if needed
 285 cache="$STATE_DIR/cache/lxc/cloud-$release"
 286 STATE_DIR="$HOME/.cache/lxc/"
 287 cache="$HOME/.cache/lxc/cloud-$release"
 288
 289 mkdir -p $cache
 290
 291 if [ -n "$tarball" ]; then
 292     url2="$tarball"
 293 else
 294     url1=`ubuntu-cloudimg-query $release $stream $arch --format "%{url}\n"`
 295     url2=`echo $url1 | sed -e 's/.tar.gz/-root\0/'`
 296 fi
 297
 298 filename=`basename $url2`
 299
 300 wgetcleanup()
 301 {
 302     rm -f $filename
 303 }
 304
 305 buildcleanup()
 306 {
 307     cd $rootfs
 308     umount -l $cache/$xdir || true
 309     rm -rf $cache
 310 }
 311
 312 # if the release doesn't have a *-rootfs.tar.gz, then create one from the
 313 # cloudimg.tar.gz by extracting the .img, mounting it loopback, and creating
 314 # a tarball from the mounted image.
 315 build_root_tgz()
 316 {
 317     url=$1
 318     filename=$2
 319
 320     xdir=`mktemp -d -p .`
 321     tarname=`basename $url`
 322     imgname="$release-*-cloudimg-$arch.img"
 323     trap buildcleanup EXIT SIGHUP SIGINT SIGTERM
 324     if [ $flushcache -eq 1 -o ! -f $cache/$tarname ]; then
 325         rm -f $tarname
 326         echo "Downloading cloud image from $url"
 327         wget $url || { echo "Couldn't find cloud image $url."; exit 1; }
 328     fi
 329     echo "Creating new cached cloud image rootfs"
 330     tar --wildcards -zxf "$tarname" "$imgname"
 331     mount -o loop $imgname $xdir
 332     (cd $xdir; tar --numeric-owner -cpzf "../$filename" .)
 333     umount $xdir
 334     rm -f $tarname $imgname
 335     rmdir $xdir
 336     echo "New cloud image cache created"
 337     trap EXIT
 338     trap SIGHUP
 339     trap SIGINT
 340     trap SIGTERM
 341 }
 342
 343 do_extract_rootfs() {
 344
 345     cd $cache
 346     if [ $flushcache -eq 1 ]; then
 347         echo "Clearing the cached images"
 348         rm -f $filename
 349     fi
 350
 351     trap wgetcleanup EXIT SIGHUP SIGINT SIGTERM
 352     if [ ! -f $filename ]; then
 353         wget $url2 || build_root_tgz $url1 $filename
 354     fi
 355     trap EXIT
 356     trap SIGHUP
 357     trap SIGINT
 358     trap SIGTERM
 359
 360     echo "Extracting container rootfs"
 361     mkdir -p $rootfs
 362     cd $rootfs
 363     if [ $in_userns -eq 1 ]; then
 364         tar --anchored --exclude="dev/*" --numeric-owner -xpzf "$cache/$filename"
 365         mkdir -p $cache/$filename/dev/pts/
 366     else
 367         tar --numeric-owner -xpzf "$cache/$filename"
 368     fi
 369 }
 370
 371 if [ -n "$tarball" ]; then
 372     do_extract_rootfs
 373 else
 374     mkdir -p "$STATE_DIR/lock/subsys/"
 375     (
 376         flock -x 200
 377         do_extract_rootfs
 378     ) 200>"$STATE_DIR/lock/subsys/lxc-ubuntu-cloud"
 379 fi
 380
 381 copy_configuration $path $rootfs $name $arch $release
 382
 383 "$CLONE_HOOK_FN" "${cloneargs[@]}" "$rootfs"
 384
 385 if [ $mapped_uid -ne -1 ]; then
 386     chown $mapped_uid $path/config
 387     chown -R $mapped_uid $STATE_DIR
 388     chown -R $mapped_uid $cache
 389 fi
 390
 391 echo "Container $name created."
 392 exit 0
 393
 394 # vi: ts=4 expandtab