#!/bin/sh
#
# Template script for generating Oracle Enterprise Linux container for LXC
# based on lxc-fedora, lxc-ubuntu
#
# Copyright © 2011 Wim Coekaerts <wim.coekaerts@oracle.com>
# Copyright © 2012 Dwight Engen <dwight.engen@oracle.com>
#
# Modified for Oracle Linux 5
# Wim Coekaerts <wim.coekaerts@oracle.com>
#
# Modified for Oracle Linux 6,7 combined OL4,5,6 into one template script
# Dwight Engen <dwight.engen@oracle.com>
#
# 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
#

# Detect use under userns (unsupported)
for arg in "$@"; do
    [ "$arg" = "--" ] && break
    if [ "$arg" = "--mapped-uid" -o "$arg" = "--mapped-gid" ]; then
        echo "This template can't be used for unprivileged containers." 1>&2
        echo "You may want to try the \"download\" template instead." 1>&2
        exit 1
    fi
done

# Make sure the usual locations are in PATH
export PATH=$PATH:/usr/sbin:/usr/bin:/sbin:/bin

die()
{
    echo "failed: $1"
    exit 1
}

is_btrfs_subvolume()
{
    if which btrfs >/dev/null 2>&1 && \
       btrfs subvolume list "$1" >/dev/null 2>&1; then
        return 0
    fi
    return 1
}

can_chcon()
{
    if which chcon >/dev/null 2>&1; then
        selinuxenabled >/dev/null 2>&1
        return $?
    fi
    return 1
}

# fix up the container_rootfs
container_rootfs_patch()
{
    echo "Patching container rootfs $container_rootfs for Oracle Linux $container_release_major.$container_release_minor"

    # copy ourself into the container to be used to --patch the rootfs when
    # yum update on certain packages is done. we do this here instead of in
    # container_rootfs_configure() in case the patching done in this function
    # is updated in the future, we can inject the updated version of ourself
    # into older containers.
    if [ $container_rootfs != "/" ]; then
        cp -f `readlink -f $0` $container_rootfs/usr/bin/lxc-patch
        if [ $container_release_major -lt "6" ]; then
            mkdir -p $container_rootfs/usr/lib/yum-plugins
            cp @DATADIR@/lxc/lxc-patch.py $container_rootfs/usr/lib/yum-plugins
        fi
        if [ $container_release_major -ge "6" ]; then
            mkdir -p $container_rootfs/usr/share/yum-plugins
            cp @DATADIR@/lxc/lxc-patch.py $container_rootfs/usr/share/yum-plugins
        fi
        mkdir -p $container_rootfs/etc/yum/pluginconf.d
        cat <<EOF > $container_rootfs/etc/yum/pluginconf.d/lxc-patch.conf
[main]
enabled=1
packages=dbus,initscripts,iptables,openssh-server,setup,selinux-policy,readahead,udev,util-linux,util-linux-ng
EOF
    fi

    if [ $container_release_major = "4" ]; then
        # yum plugin type of TYPE_INTERFACE works in all releases but gives a
        # deprecation warning on major > 4, so we default to TYPE_INTERACTIVE
        # and fix it up here
        sed -i 's|TYPE_INTERACTIVE|TYPE_INTERFACE|' $container_rootfs/usr/lib/yum-plugins/lxc-patch.py
        if [ -f $container_rootfs/etc/yum.repos.d/ULN-Base.repo ]; then
            mv $container_rootfs/etc/yum.repos.d/ULN-Base.repo \
               $container_rootfs/etc/yum.repos.d/ULN-Base.repo.lxc-disabled
        fi
        echo "plugins = 1" >>$container_rootfs/etc/yum.conf
    fi

    # "disable" selinux in the guest. The policy in the container isn't
    # likely to match the hosts (unless host == guest exactly) and the
    # kernel can only be enforcing one policy.
    #
    # The OL 5 init honors /etc/selinux/config, but note that
    # this doesnt actually disable it if it's enabled in the host, since
    # libselinux::is_selinux_enabled() in the guest will check
    # /proc/filesystems and see selinuxfs, thus reporting that it is on
    # (ie. check the output of sestatus in the guest). We also replace
    # /usr/sbin/selinuxenabled with a symlink to /bin/false so that init
    # scripts (ie. mcstransd) that call that think selinux is disabled.
    mkdir -p $container_rootfs/selinux
    echo 0 > $container_rootfs/selinux/enforce
    if [ -e $container_rootfs/etc/selinux/config ]; then
        sed -i 's|SELINUX=enforcing|SELINUX=disabled|' $container_rootfs/etc/selinux/config
    else
        mkdir -p $container_rootfs/etc/selinux
        echo "SELINUX=disabled" >$container_rootfs/etc/selinux/config
    fi
    sed -i 's|session[ \t]*required[ \t]*pam_selinux.so[ \t]*close|#session required pam_selinux.so close|' $container_rootfs/etc/pam.d/login
    sed -i 's|session[ \t]*required[ \t]*pam_selinux.so[ \t]*open|#session required pam_selinux.so open|' $container_rootfs/etc/pam.d/login
    sed -i 's|session[ \t]*required[ \t]*pam_selinux.so[ \t]*close|#session required pam_selinux.so close|' $container_rootfs/etc/pam.d/sshd
    sed -i 's|session[ \t]*required[ \t]*pam_selinux.so[ \t]*open|#session required pam_selinux.so open|' $container_rootfs/etc/pam.d/sshd

    # setting /proc/$$/loginuid doesn't work under user namespace, which
    # prevents logins from working
    sed -i 's|session[ \t]*required[ \t]*pam_loginuid.so|#session required pam_loginuid.so|' $container_rootfs/etc/pam.d/sshd
    sed -i 's|session[ \t]*required[ \t]*pam_loginuid.so|#session required pam_loginuid.so|' $container_rootfs/etc/pam.d/login

    if [ -f $container_rootfs/usr/sbin/selinuxenabled ]; then
        mv $container_rootfs/usr/sbin/selinuxenabled $container_rootfs/usr/sbin/selinuxenabled.lxcorig
        ln -s /bin/false $container_rootfs/usr/sbin/selinuxenabled
    fi

    # ensure /dev/ptmx refers to the newinstance devpts of the container, or
    # pty's will get crossed up with the hosts (https://lkml.org/lkml/2012/1/23/512)
    rm -f $container_rootfs/dev/ptmx
    ln -s pts/ptmx $container_rootfs/dev/ptmx

    # OL7 has systemd, no rc.sysinit
    if [ $container_release_major = "7" ]; then
        # with newer systemd (OL7.2), getty service include container-getty.service
        # let that be the one who manage the getty service instead
        if [ ! -f $container_rootfs/usr/lib/systemd/system/container-getty@.service ]; then
            # from mhw in the fedora template: We do need to disable the
            # "ConditionalPathExists=/dev/tty0" line or no gettys are started on
            # the ttys in the container. Lets do it in an override copy of the
            # service so it can still pass rpm verifies and not be automatically
            # updated by a new systemd version.
            sed -e 's/^ConditionPathExists=/#LXC ConditionPathExists=/' \
                    < $container_rootfs/usr/lib/systemd/system/getty\@.service \
                    > $container_rootfs/etc/systemd/system/getty\@.service
            # Setup getty service on the 4 ttys we are going to allow in the
            # default config.  Number should match lxc.tty
            ( cd $container_rootfs/etc/systemd/system/getty.target.wants
                    for i in 1 2 3 4 ; do ln -sf ../getty\@.service getty@tty${i}.service; done )
            # We only want to spawn a getty on /dev/console in lxc, libvirt-lxc
            # symlinks /dev/console to /dev/tty1
            sed -i '/Before=getty.target/a ConditionVirtualization=lxc' $container_rootfs/usr/lib/systemd/system/console-getty.service
        fi

        # disable some systemd services, set default boot, sigpwr target
        rm -f $container_rootfs/usr/lib/systemd/system/sysinit.target.wants/kmod-static-nodes.service
        chroot $container_rootfs systemctl -q disable graphical.target
        chroot $container_rootfs systemctl -q enable multi-user.target

        # systemd in userns won't be able to set /proc/self/oom_score_adj which
        # prevents the dbus service from starting
        sed -i 's|^OOMScoreAdjust|#LXC OOMScoreAdjust|' $container_rootfs/usr/lib/systemd/system/dbus.service
        return
    fi

    # silence error in checking for selinux
    sed -i 's|cat /proc/self/attr/current|cat /proc/self/attr/current 2>/dev/null|' $container_rootfs/etc/rc.sysinit
    sed -i 's|cat /proc/self/attr/current|cat /proc/self/attr/current 2>/dev/null|' $container_rootfs/etc/rc.d/rc.sysinit

    # on ol4 pam_limits prevents logins when using user namespaces
    if [ $container_release_major = "4" ]; then
        sed -i 's|session[ \t]*required[ \t]*/lib/security/\$ISA/pam_limits.so|#session required /lib/security/$ISA/pam_limits.so|' $container_rootfs/etc/pam.d/system-auth
    fi

    # avoid error in ol5 attempting to copy non-existent resolv.conf
    if [ $container_release_major = "5" ]; then
        sed -i 's|resolv.conf.predhclient|resolv.conf.predhclient 2>/dev/null|' $container_rootfs/sbin/dhclient-script
    fi

    # disable interactive ovmd asking questions
    if [ -f $container_rootfs/etc/sysconfig/ovmd ]; then
        sed -i 's|INITIAL_CONFIG=yes|INITIAL_CONFIG=no|' $container_rootfs/etc/sysconfig/ovmd
    fi

    # disable disabling of ipv4 forwarding and defrag on shutdown since
    # we mount /proc/sys ro
    if [ $container_release_major = "5" ]; then
        sed -i 's|-f /proc/sys/net/ipv4/ip_forward|-w /proc/sys/net/ipv4/ip_forward|' $container_rootfs/etc/rc.d/init.d/network
        sed -i 's|-f /proc/sys/net/ipv4/ip_always_defrag|-w /proc/sys/net/ipv4/ip_always_defrag|' $container_rootfs/etc/rc.d/init.d/network
    fi

    # disable ipv6 on ol6
    rm -f $container_rootfs/etc/sysconfig/network-scripts/init.ipv6-global

    # remove module stuff for iptables it just shows errors that are not
    # relevant in a container
    if [ -f "$container_rootfs/etc/sysconfig/iptables-config" ]; then
        sed -i 's|IPTABLES_MODULES=".*|IPTABLES_MODULES=""|' $container_rootfs/etc/sysconfig/iptables-config
        sed -i 's|IPTABLES_MODULES_UNLOAD=".*|IPTABLES_MODULES_UNLOAD="no"|' $container_rootfs/etc/sysconfig/iptables-config
    fi

    # disable readahead in the container
    if [ $container_release_major = "6" -a -e $container_rootfs/etc/sysconfig/readahead ]; then
        rm -f $container_rootfs/etc/init/readahead-collector.conf
        rm -f $container_rootfs/etc/init/readahead-disable-services.conf
        sed -i 's|READAHEAD="yes"|READAHEAD="no"|' $container_rootfs/etc/sysconfig/readahead
    fi

    if [ $container_release_major = "4" ]; then
        # enable fastboot always
        sed -i 's|\[ -f /fastboot \]|/bin/true|' $container_rootfs/etc/rc.sysinit
        sed -i 's|\[ -f /fastboot \]|/bin/true|' $container_rootfs/etc/rc.d/rc.sysinit

        # dont attempt to set kernel parameters
        sed -i 's|action $"Configuring kernel parameters|# LXC action $"Configuring kernel parameters|' $container_rootfs/etc/rc.sysinit
        sed -i 's|action $"Configuring kernel parameters|# LXC action $"Configuring kernel parameters|' $container_rootfs/etc/rc.d/rc.sysinit
        sed -i 's|action $"Setting network parameters|# LXC action $"Setting network parameters|' $container_rootfs/etc/init.d/network 2>/dev/null
        sed -i 's|action $"Setting network parameters|# LXC action $"Setting network parameters|' $container_rootfs/etc/init.d/NetworkManager 2>/dev/null
    fi

    # no need to attempt to mount /
    sed -i 's|mount -f /$|# LXC mount -f /|' $container_rootfs/etc/rc.sysinit
    sed -i 's|mount -f /$|# LXC mount -f /|' $container_rootfs/etc/rc.d/rc.sysinit
    sed -i 's|action \$"Remounting root filesystem|/bin/true # LXC action $"Remounting root filesystem|' $container_rootfs/etc/rc.sysinit
    sed -i 's|action \$"Remounting root filesystem|/bin/true # LXC action $"Remounting root filesystem|' $container_rootfs/etc/rc.d/rc.sysinit

    # disable udev in the container
    if [ $container_release_major = "4" ]; then
        sed -i 's|\[ -x /sbin/start_udev \]|# LXC no udev|' $container_rootfs/etc/rc.sysinit
        sed -i 's|\[ -x /sbin/start_udev \]|# LXC no udev|' $container_rootfs/etc/rc.d/rc.sysinit
    else
        sed -i 's|.sbin.start_udev||' $container_rootfs/etc/rc.sysinit
        sed -i 's|.sbin.start_udev||' $container_rootfs/etc/rc.d/rc.sysinit
    fi

    # disable nash raidautorun in the container since no /dev/md*
    if [ $container_release_major = "4" -o $container_release_major = "5" ]; then
        sed -i 's|echo "raidautorun /dev/md0"|echo ""|' $container_rootfs/etc/rc.sysinit
        sed -i 's|echo "raidautorun /dev/md0"|echo ""|' $container_rootfs/etc/rc.d/rc.sysinit
    fi

    # prevent rc.sysinit from attempting to loadkeys
    if [ \( $container_release_major = "4" -o $container_release_major = "5" \) -a -e $container_rootfs/etc/sysconfig/keyboard ]; then
        rm $container_rootfs/etc/sysconfig/keyboard
    fi

    # dont use the hwclock, it messes up the host's time
    if [ $container_release_major = "4" ]; then
        sed -i 's|runcmd $"Syncing hardware clock|# LXC no hwclock runcmd $"Syncing hardware clock|' $container_rootfs/etc/rc.d/init.d/halt
    else
        sed -i 's|\[ -x /sbin/hwclock|\[ 0 -eq 1|' $container_rootfs/etc/rc.d/init.d/halt
    fi
    sed -i 's|^\[ -x /sbin/hwclock|\[ 0 -eq 1|' $container_rootfs/etc/rc.sysinit
    sed -i 's|^\[ -x /sbin/hwclock|\[ 0 -eq 1|' $container_rootfs/etc/rc.d/rc.sysinit
    sed -i 's|^/sbin/hwclock|# LXC /sbin/nohwclock|' $container_rootfs/etc/rc.sysinit
    sed -i 's|^/sbin/hwclock|# LXC /sbin/nohwclock|' $container_rootfs/etc/rc.d/rc.sysinit

    # dont start lvm
    if [ $container_release_major -lt "6" -a -f $container_rootfs/sbin/lvm.static ]; then
        mv $container_rootfs/sbin/lvm.static $container_rootfs/sbin/lvm.static.lxc-disabled
    fi
    if [ $container_release_major = "6" ]; then
        touch $container_rootfs/.nolvm
    fi

    # fix assumptions that plymouth is available
    sed -i 's|\[ "$PROMPT" != no \] && plymouth|[ "$PROMPT" != no ] \&\& [ -n "$PLYMOUTH" ] \&\& plymouth|' $container_rootfs/etc/rc.sysinit
    sed -i 's|\[ "$PROMPT" != no \] && plymouth|[ "$PROMPT" != no ] \&\& [ -n "$PLYMOUTH" ] \&\& plymouth|' $container_rootfs/etc/rc.d/rc.sysinit
    rm -f $container_rootfs/etc/init/plymouth-shutdown.conf
    rm -f $container_rootfs/etc/init/quit-plymouth.conf
    rm -f $container_rootfs/etc/init/splash-manager.conf

    # dont try to unmount /dev/lxc devices
    sed -i 's|&& $1 !~ /^\\/dev\\/ram/|\&\& $2 !~ /^\\/dev\\/lxc/ \&\& $1 !~ /^\\/dev\\/ram/|' $container_rootfs/etc/init.d/halt

    # don't try to unmount swap
    sed -i 's|\[ -f /proc/swaps \]|# LXC [ -f /proc/swaps ]|' $container_rootfs/etc/init.d/halt

    # sem_open(3) checks that /dev/shm is SHMFS_SUPER_MAGIC, so make sure to
    # mount /dev/shm (normally done by dracut initrd) as tmpfs
    if [ $container_release_major = "4" -o $container_release_major = "5" ]; then
        grep -q "mount -t tmpfs tmpfs /dev/shm" $container_rootfs/etc/rc.sysinit
        if [ $? -eq 1 ]; then
            echo "mkdir -p /dev/shm && mount -t tmpfs tmpfs /dev/shm" >>$container_rootfs/etc/rc.sysinit
            echo "mkdir -p /dev/shm && mount -t tmpfs tmpfs /dev/shm" >>$container_rootfs/etc/rc.d/rc.sysinit
        fi
    fi
    if [ $container_release_major = "6" ]; then
        sed -i 's|mount -n -o remount /dev/shm >/dev/null 2>&1$|mkdir -p /dev/shm \&\& mount -t tmpfs tmpfs /dev/shm # LXC|' $container_rootfs/etc/rc.sysinit
        sed -i 's|mount -n -o remount /dev/shm >/dev/null 2>&1$|mkdir -p /dev/shm \&\& mount -t tmpfs tmpfs /dev/shm # LXC|' $container_rootfs/etc/rc.d/rc.sysinit
    fi

    # there might be other services that are useless but the below set is a good start
    # some of these might not exist in the image, so we silence chkconfig complaining
    # about the service file not being found
    for service in \
        acpid apmd auditd autofs cpuspeed dund gpm haldaemon hidd    \
        ip6tables irqbalance iscsi iscsid isdn kdump kudzu      \
        lm_sensors lvm2-monitor mdmonitor microcode_ctl         \
        ntpd pcmcia postfix sendmail udev-post xfs ;
    do
        chroot $container_rootfs chkconfig 2>/dev/null $service off
    done

    for service in rsyslog ;
    do
        chroot $container_rootfs chkconfig 2>/dev/null $service on
    done
}

container_rootfs_configure()
{
    container_rootfs_patch
    echo "Configuring container for Oracle Linux $container_release_major.$container_release_minor"

    # configure the network to use dhcp. we set DHCP_HOSTNAME so the guest
    # will report its name and be resolv'able by the hosts dnsmasq
    cat <<EOF > $container_rootfs/etc/sysconfig/network-scripts/ifcfg-eth0
DEVICE=eth0
BOOTPROTO=dhcp
ONBOOT=yes
HOSTNAME=$name
DHCP_HOSTNAME=\`hostname\`
NM_CONTROLLED=no
TYPE=Ethernet
EOF

    # set the hostname
    if [ $container_release_major -ge "7" ]; then
        # systemd honors /etc/hostname
        echo "$name" >$container_rootfs/etc/hostname
    fi
    cat <<EOF > $container_rootfs/etc/sysconfig/network
NETWORKING=yes
NETWORKING_IPV6=no
HOSTNAME=$name
EOF

    # set minimal hosts
    echo "127.0.0.1 localhost $name" > $container_rootfs/etc/hosts

    # this file has to exist for libvirt/Virtual machine monitor to boot the container
    touch $container_rootfs/etc/mtab

    # setup console and tty[1-4] for login. note that /dev/console and
    # /dev/tty[1-4] will be symlinks to the ptys /dev/lxc/console and
    # /dev/lxc/tty[1-4] so that package updates can overwrite the symlinks.
    # lxc will maintain these links and bind mount ptys over /dev/lxc/*
    # since lxc.tty.dir is specified in the config.

    # allow root login on console, tty[1-4], and pts/0 for libvirt
    echo "# LXC (Linux Containers)" >>$container_rootfs/etc/securetty
    echo "lxc/console" >>$container_rootfs/etc/securetty
    for i in 1 2 3 4; do
        echo "lxc/tty$i" >>$container_rootfs/etc/securetty
    done
    echo "# For libvirt/Virtual Machine Monitor" >>$container_rootfs/etc/securetty
    for i in 0 1 2 3 4; do
        echo "pts/$i" >>$container_rootfs/etc/securetty
    done

    # prevent mingetty from calling vhangup(2) since it fails with userns
    if [ -f $container_rootfs/etc/init/tty.conf ]; then
        sed -i 's|mingetty|mingetty --nohangup|' $container_rootfs/etc/init/tty.conf
    fi

    # create maygetty which only spawns a getty on the console when running
    # under lxc, not libvirt-lxc which symlinks /dev/console to the same pty
    # as /dev/tty1
    cat <<EOF >$container_rootfs/sbin/maygetty
#!/bin/sh
if [ "\$container" = "lxc" ]; then
    exec /sbin/mingetty \$@
fi
exec sleep infinity
EOF
    chmod 755 $container_rootfs/sbin/maygetty

    # start a getty on /dev/console, /dev/tty[1-4]
    if [ $container_release_major = "4" -o $container_release_major = "5" ]; then
        sed -i 's|mingetty|mingetty --nohangup|' $container_rootfs/etc/inittab
        sed -i '/1:2345:respawn/i cns:2345:respawn:/sbin/maygetty --nohangup --noclear console' $container_rootfs/etc/inittab
        sed -i '/5:2345:respawn/d' $container_rootfs/etc/inittab
        sed -i '/6:2345:respawn/d' $container_rootfs/etc/inittab
    fi

    if [ $container_release_major = "6" ]; then
        cat <<EOF > $container_rootfs/etc/init/console.conf
# console - getty
#
# This service maintains a getty on the console from the point the system is
# started until it is shut down again.

start on stopped rc RUNLEVEL=[2345]
stop on runlevel [!2345]
env container

respawn
exec /sbin/maygetty --nohangup --noclear /dev/console
EOF
    fi

    # lxc-shutdown sends SIGPWR to init, OL4 and OL5 have SysVInit, just
    # make it do shutdown now instead of delaying 2 minutes.  OL6 uses
    # upstart, so we create an upstart job to handle SIGPWR to shut down
    # cleanly.  We use "init 0" instead of shutdown -h now to avoid SELinux
    # permission denied when upstart's shutdown tries to connect to the
    # /com/ubuntu/upstart socket.
    if [ $container_release_major = "4" -o $container_release_major = "5" ]; then
        sed -i 's|pf::powerfail:/sbin/shutdown -f -h +2 "Power Failure; |pf::powerfail:/sbin/shutdown -f -h now "|' $container_rootfs/etc/inittab
    elif [ $container_release_major = "6" ]; then
        cat <<EOF > $container_rootfs/etc/init/power-status-changed.conf
# power-status-changed - used to cleanly shut down the container
#
# This task is run whenever init receives SIGPWR
# Used to shut down the machine.

start on power-status-changed

exec init 0
EOF
    fi

    # start with a clean /var/log/messages
    rm -f $container_rootfs/var/log/messages

    # set initial timezone as on host
    if [ -f /etc/sysconfig/clock ]; then
        . /etc/sysconfig/clock
        if [ $container_release_major = "5" -o $container_release_major = "6" ]; then
                echo ZONE=$ZONE > $container_rootfs/etc/sysconfig/clock
                chroot $container_rootfs tzdata-update
        else
                ZONE="${ZONE// /_}"
                chroot $container_rootfs ln -sf ../usr/share/zoneinfo/$ZONE /etc/localtime
        fi
    else
        ZONE=`readlink /etc/localtime | sed -s "s/\.\.\/usr\/share\/zoneinfo\///g"`
        if [ "$ZONE" ]; then
                if [ $container_release_major = "5" -o $container_release_major = "6" ]; then
                        echo ZONE=$ZONE > $container_rootfs/etc/sysconfig/clock
                        chroot $container_rootfs tzdata-update
                else
                        # if /etc/localtime is a symlink, this should preserve it.
                        cp -a /etc/localtime $container_rootfs/etc/localtime
                fi
        else
                echo "Timezone in container is not configured. Adjust it manually."
        fi
    fi

    # add oracle user
    chroot $container_rootfs useradd -m -s /bin/bash oracle
    printf "Added container user:\033[1moracle\033[0m\n"
    printf "Added container user:\033[1mroot\033[0m\n"
}

# create the container's lxc config file
container_config_create()
{
    echo "Create configuration file $cfg_dir/config"
    mkdir -p $cfg_dir || die "unable to create config dir $cfg_dir"

    echo "# Common configuration" >> $cfg_dir/config
    if [ -e "@LXCTEMPLATECONFIG@/oracle.common.conf" ]; then
        echo "lxc.include = @LXCTEMPLATECONFIG@/oracle.common.conf" >> $cfg_dir/config
    fi

    cat <<EOF >> $cfg_dir/config || die "unable to create $cfg_dir/config"
# Container configuration for Oracle Linux $container_release_major.$container_release_minor
lxc.arch = $arch
lxc.uts.name = $name
EOF
    grep -q "^lxc.rootfs.path" $cfg_dir/config 2>/dev/null || echo "lxc.rootfs.path = $container_rootfs" >> $cfg_dir/config

    if [ $container_release_major != "4" ]; then
        echo "lxc.cap.drop = sys_resource" >>$cfg_dir/config
    fi

    # systemd services like logind and journald need these
    if [ $container_release_major != "7" ]; then
        echo "lxc.cap.drop = setfcap setpcap" >>$cfg_dir/config
    fi

    echo "# Networking" >>$cfg_dir/config
    # see if the default network settings were already specified
    lxc_network_type=`grep '^lxc.net.0.type' $cfg_dir/config | awk -F'[= \t]+' '{ print $2 }'`
    if [ -z "$lxc_network_type" ]; then
        echo "lxc.net.0.type = veth" >>$cfg_dir/config
        lxc_network_type=veth
    fi

    lxc_network_link=`grep '^lxc.net.0.link' $cfg_dir/config | awk -F'[= \t]+' '{ print $2 }'`
    if [ -z "$lxc_network_link" ]; then
        echo "lxc.net.0.link = lxcbr0" >>$cfg_dir/config
        lxc_network_link=lxcbr0
    fi

    lxc_network_hwaddr=`grep '^lxc.net.0.hwaddr' $cfg_dir/config | awk -F'[= \t]+' '{ print $2 }'`
    if [ -z "$lxc_network_hwaddr" ]; then
        # generate a hwaddr for the container
        # see http://sourceforge.net/tracker/?func=detail&aid=3411497&group_id=163076&atid=826303
        local hwaddr="00:16:3e:`dd if=/dev/urandom bs=8 count=1 2>/dev/null |od -t x8 | \
                        head -n1 | awk '{print $2}' | cut -c1-6 | \
                        sed 's/\(..\)/\1:/g; s/.$//'`"
        echo "lxc.net.0.hwaddr = $hwaddr" >>$cfg_dir/config
    fi

    lxc_network_flags=`grep '^lxc.net.0.flags' $cfg_dir/config | awk -F'[= \t]+' '{ print $2 }'`
    if [ -z "$lxc_network_flags" ]; then
        echo "lxc.net.0.flags = up" >>$cfg_dir/config
    fi

    cat <<EOF >> $cfg_dir/config || die "unable to create $cfg_dir/config"
lxc.net.0.name = eth0
lxc.net.0.mtu = 1500
EOF
}

container_rootfs_clone()
{
    if is_btrfs_subvolume $template_rootfs; then
        # lxc-create already made $container_rootfs a btrfs subvolume, but
        # in this case we want to snapshot the original subvolume so we we
        # have to delete the one that lxc-create made
        btrfs subvolume delete $container_rootfs
        btrfs subvolume snapshot $template_rootfs $container_rootfs || die "btrfs clone template"
    else
        echo "Copying rootfs ..."
        cp -axT $template_rootfs $container_rootfs || die "copy template"
    fi
}

container_rootfs_repo_create()
{
    echo "# LXC generated .repo file" >$1
    echo "[$2]" >>$1
    echo "name=Oracle Linux $container_release_major.$container_release_minor ($basearch)" >>$1
    echo "baseurl=$3/" >>$1
    echo "enabled=1" >>$1
    echo "skip_if_unavailable=1" >>$1

    if [ "$4" != "" ]; then
        echo "gpgkey=$yum_url/RPM-GPG-KEY-oracle-ol$container_release_major" >>$1
        echo "gpgcheck=1" >>$1
    else
        echo "gpgcheck=0" >>$1
    fi
}

container_rootfs_dev_create()
{
    # create required devices. note that /dev/console will be created by lxc
    # or libvirt itself to be a symlink to the right pty.
    # take care to not nuke /dev in case $container_rootfs isn't set
    dev_path="$container_rootfs/dev"
    if [ $container_rootfs != "/" -a -d $dev_path ]; then
        rm -rf $dev_path
    fi
    mkdir -p $dev_path
    if can_chcon; then
        # ensure symlinks created in /dev have the right context
        chcon -t device_t $dev_path
    fi
    mknod -m 666  $dev_path/null c 1 3
    mknod -m 666  $dev_path/zero c 1 5
    mknod -m 666  $dev_path/random c 1 8
    mknod -m 666  $dev_path/urandom c 1 9
    mkdir -m 755  $dev_path/pts
    mkdir -m 1777 $dev_path/shm
    mknod -m 666  $dev_path/tty c 5 0
    mknod -m 666  $dev_path/tty1 c 4 1
    mknod -m 666  $dev_path/tty2 c 4 2
    mknod -m 666  $dev_path/tty3 c 4 3
    mknod -m 666  $dev_path/tty4 c 4 4
    mknod -m 666  $dev_path/full c 1 7
    mknod -m 600  $dev_path/initctl p

    # set selinux labels same as host
    if can_chcon; then
        for node in null zero random urandom pts shm \
                    tty tty0 tty1 tty2 tty3 tty4 full ;
        do
            chcon --reference /dev/$node $dev_path/$node 2>/dev/null
        done
    fi
}

container_rootfs_create()
{
    if can_chcon; then
        chcon --reference / $container_rootfs 2>/dev/null
    fi

    cmds="rpm wget yum"
    if [ $container_release_major -lt "6" ]; then
        if [ $host_distribution = "Ubuntu" -o $host_distribution = "Debian" ]; then
            db_dump_cmd="db5.1_dump"
        fi
        if [ $host_distribution = "OracleServer" -o \
             $host_distribution = "Fedora" ]; then
            db_dump_cmd="db_dump"
        fi

        cmds="$cmds $db_dump_cmd file"
    fi
    for cmd in $cmds; do
        which $cmd >/dev/null 2>&1
        if [ $? -ne 0 ]; then
            die "The $cmd command is required, please install it"
        fi
    done

    mkdir -p @LOCALSTATEDIR@/lock/subsys
    (
        flock -x 9
        if [ $? -ne 0 ]; then
            die "The template is busy."
        fi

        echo "Yum installing release $container_release_major.$container_release_minor for $basearch"

        if [ -n "$repourl" ]; then
            yum_url=$repourl
        else
            yum_url=http://public-yum.oracle.com
        fi
        if [ $container_release_major = "4" -o $container_release_major = "5" ]; then
            latest_L="el"
            latest_U="EL"
        else
            latest_L="ol"
            latest_U="OL"
        fi

        if [ -n "$baseurl" ]; then
            # create .repo pointing at baseurl
            repo="lxc-install"
            mkdir -p $container_rootfs/etc/yum.repos.d
            container_rootfs_repo_create \
                $container_rootfs/etc/yum.repos.d/lxc-install.repo $repo $baseurl
        else
            # get public-yum repo file
            if   [ $container_release_major = "4" ]; then
                repofile=public-yum-el4.repo
            elif [ $container_release_major = "5" ]; then
                repofile=public-yum-el5.repo
            elif [ $container_release_major = "6" ]; then
                repofile=public-yum-ol6.repo
            elif [ $container_release_major = "7" ]; then
                repofile=public-yum-ol7.repo
            else
                die "Unsupported release $container_release_major"
            fi

            mkdir -p $container_rootfs/etc/yum.repos.d
            wget -q $yum_url/$repofile -O $container_rootfs/etc/yum.repos.d/$repofile
            if [ $? -ne 0 ]; then
                die "Unable to download repo file $yum_url/$repofile, release unavailable"
            fi

            # yum will take $basearch from host, so force the arch we want
            sed -i "s|\$basearch|$basearch|" $container_rootfs/etc/yum.repos.d/$repofile

            # replace url if they specified one
            if [ -n "$repourl" ]; then
                sed -i "s|baseurl=http://public-yum.oracle.com/repo|baseurl=$repourl/repo|" $container_rootfs/etc/yum.repos.d/$repofile
                sed -i "s|gpgkey=http://public-yum.oracle.com|gpgkey=$repourl|" $container_rootfs/etc/yum.repos.d/$repofile
            fi

            # disable all repos, then enable the repo for the version we are installing.
            if [ $container_release_minor = "latest" ]; then
                repo=$latest_L""$container_release_major"_"$container_release_minor
            elif [ $container_release_major = "7" ]; then
                    repo="ol"$container_release_major"_u"$container_release_minor"_base"
            elif [ $container_release_major = "6" ]; then
                if   [ $container_release_minor = "0" ]; then
                    repo="ol"$container_release_major"_ga_base"
                else
                    repo="ol"$container_release_major"_u"$container_release_minor"_base"
                fi
            elif [ $container_release_major = "5" ]; then
                if   [ $container_release_minor = "0" ]; then
                    repo="el"$container_release_major"_ga_base"
                elif [ $container_release_minor -lt "6" ]; then
                    repo="el"$container_release_major"_u"$container_release_minor"_base"
                else
                    repo="ol"$container_release_major"_u"$container_release_minor"_base"
                fi
            elif [ $container_release_major = "4" -a $container_release_minor -gt "5" ]; then
                repo="el"$container_release_major"_u"$container_release_minor"_base"
            else
                die "Unsupported release $container_release_major.$container_release_minor"
            fi
            sed -i "s|enabled=1|enabled=0|" $container_rootfs/etc/yum.repos.d/$repofile
            sed -i "/\[$repo\]/,/\[/ s/enabled=0/enabled=1/" $container_rootfs/etc/yum.repos.d/$repofile
        fi

        container_rootfs_dev_create

        # don't put devpts,proc, nor sysfs in here, it will already be mounted for us by lxc/libvirt
        echo "" >$container_rootfs/etc/fstab

        # create rpm db, download and yum install minimal packages
        mkdir -p $container_rootfs/var/lib/rpm
        rpm --root $container_rootfs --initdb
        yum_args="--installroot $container_rootfs --disablerepo=* --enablerepo=$repo -y --nogpgcheck"
        min_pkgs="yum initscripts passwd rsyslog vim-minimal openssh-server openssh-clients dhclient chkconfig rootfiles policycoreutils oraclelinux-release"
        if [ $container_release_major -lt "6" ]; then
            min_pkgs="$min_pkgs db4-utils"
        fi

        # we unshare the mount namespace because yum installing the ol4
        # packages causes $rootfs/proc to be mounted on
        lxc-unshare -s MOUNT yum -- $yum_args install $min_pkgs $user_pkgs
        if [ $? -ne 0 ]; then
            die "Failed to download and install the rootfs, aborting."
        fi

        # rsyslog and pam depend on coreutils for some common commands in
        # their POSTIN scriptlets, but coreutils wasn't installed yet. now
        # that coreutils is installed, reinstall the packages so their POSTIN
        # runs right. similarly, libutempter depends on libselinux.so.1 when
        # it runs /usr/sbin/groupadd, so reinstall it too
        redo_pkgs=""
        if [ $container_release_major = "5" ]; then
            if   [ $container_release_minor = "latest" ]; then
                redo_pkgs="pam rsyslog libutempter"
            elif [ $container_release_minor -lt 2 ]; then
                redo_pkgs="pam"
            elif [ $container_release_minor -lt 6 ]; then
                redo_pkgs="pam rsyslog"
            elif [ $container_release_minor -gt 5 ]; then
                redo_pkgs="pam rsyslog libutempter"
            fi
        fi
        # shadow utils fails on ol4 and ol6.1
        if [ $container_release_major = "4" -o \
             $container_release_major = "6" -a $container_release_minor = "1" ]; then
            redo_pkgs="shadow-utils"
        fi
        if [ x"$redo_pkgs" != x ]; then
            rpm --root $container_rootfs --nodeps -e $redo_pkgs
            lxc-unshare -s MOUNT yum -- $yum_args install $redo_pkgs
            if [ $? -ne 0 ]; then
                die "Unable to reinstall packages"
            fi
        fi

        # if installing from a baseurl, create a .repo that the container
        # can use to update to _latest from http://public-yum.oracle.com
        if [ -n "$baseurl" ]; then
            container_rootfs_repo_create \
                "$container_rootfs/etc/yum.repos.d/public-yum-"$latestL""$container_release_major".repo" \
                $latest_L""$container_release_major"_latest" \
                $yum_url"/repo/OracleLinux/"$latest_U""$container_release_major"/latest/$basearch" gpg
        fi

        # these distributions put the rpm database in a place the guest is
        # not expecting it, so move it
        if [ $host_distribution = "Ubuntu" -o $host_distribution = "Debian" ]; then
            mv $container_rootfs/$HOME/.rpmdb/* $container_rootfs/var/lib/rpm
        fi

        # if the native rpm created the db with Hash version 9, we need to
        # downgrade it to Hash version 8 for use with OL5.x
        db_version=`file $container_rootfs/var/lib/rpm/Packages | \
                    grep -o 'version [0-9]*' |awk '{print $2}'`
        if [ $container_release_major -lt "6" -a $db_version != "8" ]; then
            echo "Fixing (downgrading) rpm database from version $db_version"
            rm -f $container_rootfs/var/lib/rpm/__db*
            for db in $container_rootfs/var/lib/rpm/* ; do
                $db_dump_cmd $db |chroot $container_rootfs db_load /var/lib/rpm/`basename $db`.new
                mv $db.new $db
            done
        fi

        # the host rpm may not be the same as the guest, rebuild the db with
        # the guest rpm version
        echo "Rebuilding rpm database"
        rm -f $container_rootfs/var/lib/rpm/__db*
        chroot $container_rootfs rpm --rebuilddb >/dev/null 2>&1

    ) 9>@LOCALSTATEDIR@/lock/subsys/lxc-oracle-$name
    if [ $? -ne 0 ]; then
        exit 1
    fi
}

container_release_get()
{
    if [ -f $1/etc/oracle-release ]; then
        container_release_version=`cat $1/etc/oracle-release |awk '/^Oracle/ {print $5}'`
        container_release_major=`echo $container_release_version |awk -F '.' '{print $1}'`
        container_release_minor=`echo $container_release_version |awk -F '.' '{print $2}'`
    elif grep -q "Enterprise Linux AS" $1/etc/redhat-release; then
        container_release_major=`cat $1/etc/redhat-release |awk '{print $7}'`
        container_release_minor=`cat $1/etc/redhat-release |awk '{print $10}' |tr -d ")"`
        container_release_version="$container_release_major.$container_release_minor"
    elif grep -q "Enterprise Linux Server" $1/etc/redhat-release; then
        container_release_version=`cat $1/etc/redhat-release |awk '{print $7}'`
        container_release_major=`echo $container_release_version |awk -F '.' '{print $1}'`
        container_release_minor=`echo $container_release_version |awk -F '.' '{print $2}'`
    else
        echo "Unable to determine container release version"
        exit 1
    fi
}

usage()
{
    cat <<EOF
  -a|--arch=<arch>        architecture (ie. i386, x86_64)
  -R|--release=<release>  release to download for the new container
  --rootfs=<path>         rootfs path
  -r|--rpms=<rpm name>    additional rpms to install into container
  -u|--url=<url>          replace yum repo url (ie. Oracle public-yum mirror)
     --baseurl=<url>      use package repository (ie. file:///mnt)
                          arch and release must also be specified
  -t|--templatefs=<path>  copy/clone rootfs at path instead of downloading
  -P|--patch=<path>       only patch the rootfs at path for use as a container
  -h|--help

Release is of the format "major.minor", for example "5.8", "6.3", or "6.latest"
This template supports Oracle Linux releases 4.6 - 7.0
EOF
    return 0
}

options=$(getopt -o hp:n:a:R:r:u:t: -l help,rootfs:,path:,name:,arch:,release:,rpms:,url:,templatefs:,patch:,baseurl: -- "$@")
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)      cfg_dir=$2; shift 2;;
        --rootfs)       container_rootfs=$2; shift 2;;
        -n|--name)      name=$2; shift 2;;
        -a|--arch)      arch=$2; shift 2;;
        -R|--release)       container_release_version=$2; shift 2;;
        -r|--rpms)      user_pkgs=$2; shift 2;;
        -u|--url)       repourl=$2; shift 2;;
        -t|--templatefs)    template_rootfs=$2; shift 2;;
        --patch)        patch_rootfs=$2; shift 2;;
        --baseurl)      baseurl=$2; shift 2;;
        --)                 shift 1; break ;;
        *)                  break ;;
    esac
done

# make sure mandatory args are given and valid
if [ "$(id -u)" != "0" ]; then
    echo "This script should be run as 'root'"
    exit 1
fi

if [ -n "$baseurl" ]; then
    if [ "$arch" = "" -o "$container_release_version" = "" ]; then
        echo "The --arch and --release must be specified when using --baseurl"
        usage
        exit 1
    fi
fi

if [ "$arch" = "" ]; then
    arch=$(uname -m)
fi

if [ -n "$patch_rootfs" ]; then
    container_rootfs="$patch_rootfs"
    container_release_get $container_rootfs
    container_rootfs_patch
    exit 0
fi

if [ -z $name ]; then
    echo "Container name must be given"
    usage
    exit 1
fi

if [ -z $cfg_dir ]; then
    echo "Configuration directory must be given, check lxc-create"
    usage
    exit 1
fi

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

if [ "$arch" != "i386" -a "$arch" != "x86_64" ]; then
    echo "Bad architecture given, check lxc-create"
    usage
    exit 1
fi

if which lsb_release >/dev/null 2>&1; then
    host_distribution=`lsb_release --id |awk '{print $3}'`
    host_release_version=`lsb_release --release |awk '{print $2}'`
    host_release_major=`echo $host_release_version |awk -F '.' '{print $1}'`
    host_release_minor=`echo $host_release_version |awk -F '.' '{print $2}'`
else
    if   [ -f /etc/fedora-release ]; then
       host_distribution="Fedora"
       host_release_version=`cat /etc/fedora-release |awk '{print $3}'`
       host_release_major=$host_release_version
       host_release_minor=0
    elif [ -f /etc/oracle-release ]; then
       host_distribution="OracleServer"
       host_release_version=`cat /etc/oracle-release |awk '{print $5}'`
       host_release_major=`echo $host_release_version |awk -F '.' '{print $1}'`
       host_release_minor=`echo $host_release_version |awk -F '.' '{print $2}'`
    else
       echo "Unable to determine host distribution, ensure lsb_release is installed"
       exit 1
    fi
fi
echo "Host is $host_distribution $host_release_version"

if [ -z "$container_rootfs" ]; then
    container_rootfs="$cfg_dir/rootfs"
fi

if [ -n "$template_rootfs" ]; then
    container_release_get $template_rootfs
else
    if [ -z "$container_release_version" ]; then
        if [ $host_distribution = "OracleServer" ]; then
            container_release_version=$host_release_version
        else
            echo "No release specified with -R, defaulting to 6.5"
            container_release_version="6.5"
        fi
    fi
    container_release_major=`echo $container_release_version |awk -F '.' '{print $1}'`
    container_release_minor=`echo $container_release_version |awk -F '.' '{print $2}'`
fi

container_config_create
if [ -n "$template_rootfs" ]; then
    container_rootfs_clone
else
    container_rootfs_create
fi

container_release_get $container_rootfs

container_rootfs_configure

echo "Container : $container_rootfs"
echo "Config    : $cfg_dir/config"
echo "Network   : eth0 ($lxc_network_type) on $lxc_network_link"