#! /bin/bash
  
  # Copyright (c) 2007 XenSource, Inc.
  #
  # This script installs or updates the XE support packages installed in a guest.
  
  os_distro=""
  os_majorver=""
  install_kernel=1
  interactive=1
  
  if [ -z "${DATADIR}" ] ; then
      DATADIR=$(dirname $0)
  fi
  
  usage()
  {
      echo "usage: install.sh [-d <DISTRO> -m <MAJOR>] [-k]"
      echo ""
      echo "    -d <DISTRO>       Specifies the distro name."
      echo "    -m <MAJOR>        Specifies the major version of the distro release."
      echo "    -k                Do not update the kernel."
      echo "    -n                Non interactive mode."
      echo ""
      echo "The -d and -m options must be used together. If neither is given then"
      echo "auto-detection will be attempted."
      exit 1
  }
  while getopts d:hkm:n OPT ; do
      case $OPT in
  	d) os_distro="$OPTARG" ;;
  	k) install_kernel=0 ;;
  	m) os_majorver="$OPTARG" ;;
  	n) interactive=0 ;;
  
  	h|\?) usage ;;
      esac
  done
  
  if [ -z "${os_distro}" -a -n "${os_majorver}" ] || \
     [ -n "${os_distro}" -a -z "${os_majorver}" ] ; then
      echo "Distribution name (-d) and major version (-m) must be specified"
      echo "together on the command line."
      exit 1
  fi
  
  if [ -z "${os_distro}" ] ; then
      if [ -z "${XE_LINUX_DISTRIBUTION}" ] ; then
  	XE_LINUX_DISTRIBUTION=${DATADIR}/xe-linux-distribution
      fi
  
      if [ ! -f "${XE_LINUX_DISTRIBUTION}" ] ; then
  	echo "Fatal Error: xe-linux-distribution script not found in ${DATADIR}."
  	exit 1
      fi
  
      if [ ! -f "${DATADIR}/versions.deb" -o ! -f "${DATADIR}/versions.rpm" ] ; then
  	echo "Fatal Error: versions.deb or versions.rpm not found in ${DATADIR}."
  	exit 1
      fi
  
      eval $(${XE_LINUX_DISTRIBUTION})
      if [ $? -ne 0 -o -z "${os_distro}" -o -z "${os_majorver}" ] ; then
  	echo "Fatal Error: Failed to determine Linux distribution and version."
  	exit 1
      fi
  
      echo "Detected \`${os_name}' (${os_distro} version ${os_majorver})."
      echo
  else
      echo "Distribution \`${os_distro}' version \`${os_majorver}' given on command line."
      echo
  fi
  
  ARCH=$(uname -m | sed -e 's/i.86/i386/g')
  case "${ARCH}" in
      i386|x86_64) ;;
      *)
  	echo "Architecture ${ARCH} is not supported"
  	exit 1
  	;;
  esac
  
  failure()
  {
  	echo "Unable to install guest packages for distribution"
  	if [ -n "${os_name}" ] ; then
  	    echo "${os_name} (${os_distro})."
  	else
  	    echo "${os_distro}."
  	fi
  	echo
  	if [ $# -gt 0 ] ; then
  	    echo $@
  	    echo
  	fi
  	echo "You should manually install a version of"
  	echo "xe-guest-utilities which is suitable for your"
  	echo "distribution."
  	exit 1
  }
  
  select_rpm_utilities()
  {
      if [ -f "${DATADIR}/versions.rpm" ] ; then
  	source ${DATADIR}/versions.rpm
  	XGU=
  	for p in $(eval echo \${XE_GUEST_UTILITIES_PKG_FILE_${ARCH}}) ; do
  	    XGU="$XGU ${DATADIR}/${p}"
  	done
      else
  	echo "Warning: Guest utilities not found in ${DATADIR}."
      fi
  }
  
  select_pkgs_rhel()
  {
      GUEST_PKG_TYPE=rpm
  
      case "${os_distro}${os_majorver}" in
  	rhel4|centos4)
  	    # RHEL 4.9 already contains a Xen aware kernel
  	    if [ "${ARCH}" == "i386" -a "${install_kernel}" -gt 0 ] ; then
  		REQUIRE_XENBLK_KO=yes
  		REQUIRE_XENNET_KO=yes
  	    fi
  	    ;;
  	rhel5|centos5|oracle5|scientific5)
  	    # No additional kernel package
  	    ;;

  	rhel6|centos6|oracle6|scientific6|neokylin5|neokylin6|asianux4|turbo12)

  	    # No additional kernel package
  	    ;;

  	rhel7|centos7|oracle7|scientific7|neokylin7)

  	    # No additional kernel package
  	    ;;
  	rhel3|fedora*)
  	    # Not officially supported therefore no additional packages required.
  	    ;;
  	*)
  	    failure "Unknown RedHat Linux variant \`${os_distro} ${os_majorver}'."
  	    ;;
      esac
  
      select_rpm_utilities
  }
  
  select_pkgs_sles()
  {
      GUEST_PKG_TYPE=rpm
  
      case "${os_distro}${os_majorver}" in
  	sles9|"suse linux9")
              # SLES9.4+ already contains a Xen aware kernel
  	    ;;
  	sles10|"suse linux10") 
              # SLES10 already contains a Xen aware kernel
  	    ;;
  	sles11|"suse linux11")
              # SLES11 already contains a Xen aware kernel
  	    ;;
  	sles12|"suse linux12")
              # SLES12 already contains a Xen aware kernel
  	    ;;
  	*)
  	    failure "Unknown SuSE Linux variant \`${os_distro} ${os_majorver}'."
  	    ;;
      esac
  
      select_rpm_utilities
  }
  
  select_pkgs_coreos()
  {
      GUEST_PKG_TYPE=coreos
      XGU="xe-linux-distribution"
  }
  
  select_pkgs_debian()
  {
      GUEST_PKG_TYPE=deb
  
      case ${os_distro}:${os_majorver}:${os_minorver} in
  	debian:[0-5]:*)
  	    failure "This version of Debian is no longer supported by these utilities."
  	    ;;
  	debian:[6-9]:*)      ;;
  	debian:[1-9][0-9]:*) ;;
  	debian:testing:*|debian:unstable:*) ;;

  	linx:*:*) ;;
  	yinhe:*:*) ;;

  
  	ubuntu:[1-9]:*)
  	    failure "This version of Ubuntu is no longer supported by these utilities."
  	    ;;
  	ubuntu:[1-9][0-9]:*) ;;
          *)
  	    failure "Unknown Debian variant ${os_distro}:${os_majorver}:${os_minorver}"
  	    ;;
      esac
  
      case ${ARCH} in
  	i386) DARCH=i386 ;;
  	x86_64) DARCH=amd64 ;;
      esac
  
      if [ -f "${DATADIR}/versions.deb" ] ; then
  	source ${DATADIR}/versions.deb
  	XGU=${DATADIR}/$(eval echo \${XE_GUEST_UTILITIES_PKG_FILE_${DARCH}})
      else
  	echo "Warning: Guest utilities not found in ${DATADIR}."
      fi
  }
  
  select_pkgs_xe()
  {
      GUEST_PKG_TYPE=rpm
  
      select_rpm_utilities
  }
  
  update_lvm_configuration_required()
  {
      if test "${os_distro}" != rhel
      then
          return 1
      fi
      if test ${os_majorver} != 4
      then
          return 1
      fi
      if test \! -f /etc/lvm/lvm.conf
      then
          return 1
      fi
      lvm_types="`grep -e '^[ \t]*types' /etc/lvm/lvm.conf`"
      if [[ -z "$lvm_types" || "$lvm_types" != *\"xvd\"* ]]
      then
          return 0
      fi
      return 1
  }
  
  update_lvm_configuration()
  {
      if test -z "`grep -e '^[ \t]*types' /etc/lvm/lvm.conf`"
      then
          sed -i '/^[ \t]*devices[ \t]*{[ \t]*/a \    types = ["xvd", 16]' /etc/lvm/lvm.conf
      else
          sed -i 's/^[ \t]*types.*/    types = ["xvd", 16]/g' /etc/lvm/lvm.conf
      fi
  }
  
  update_inittab_configuration_required()
  {
      case "${os_distro}${os_majorver}" in
      sles10|"suse linux10"|sles11|"suse linux11")
        # SLES10 starts up two gettys, and we want to disable one of them
        if grep -Eq '^cons:12345:respawn:/sbin/smart_agetty -L 42 console' /etc/inittab; then
          if grep -Eq '^x0:12345:respawn:/sbin/agetty -L 9600 xvc0 xterm' /etc/inittab; then
              return 0
          fi
        fi
        ;;
      *)
        ;;
      esac
      return 1
  }
  
  update_inittab_configuration()
  {
      case "${os_distro}${os_majorver}" in
      sles10|"suse linux10"|sles11|"suse linux11")
        # Disable duplicate getty
        sed -i 's/^x0:12345:respawn:/# x0:12345:respawn:/g' /etc/inittab
        ;;
      *)
        ;;
      esac
      /sbin/telinit q
  }
  
  update_arp_notify_required()
  {
      # PV ops kernels do not emit gratuitous ARPs on migrate unless this is set
      file=/proc/sys/net/ipv4/conf/all/arp_notify
      if [ -f ${file} ] ; then
  	val=$(cat ${file})
  	if [ "${val}" = 0 ] ; then
  	    return 0;
  	fi
      fi
      return 1
  }
  
  update_arp_notify_configuration()
  {
      file=/etc/sysctl.conf
      if [ -e "${file}" ] ; then
          sed -i -e 's/\(^\s*net\.ipv4\.conf\.[^.]\+\.arp_notify\s*=\s*0\)/#Auto-disabled by xs-tools:install.sh
  #\1/' ${file}
      else
          folder=/etc/sysctl.d/
          if [ ! -d "${folder}" ] ; then
              echo "Cannot update arp_notify configuration as neither ${file} nor ${folder} present" >&2
              return 1
          fi
          file=${folder}/10-enable-arp-notify.conf
      fi
      echo -e  "# Auto-enabled by xs-tools:install.sh
  net.ipv4.conf.all.arp_notify = 1" >> ${file}
      return 0
  }
  
  update_modules_configuration_required()
  {
      if [ -f "/etc/modprobe.conf" ] ; then
  	conf="/etc/modprobe.conf"
      elif [ -f "/etc/modules.conf" ] ; then
  	conf="/etc/modules.conf"
      else
  	return 1
      fi
  
      if [ -z "${KERNEL}" ] ; then
  	return 1
      fi
  
      if [ X"${REQUIRE_XENNET_KO}" = "Xyes" ] ; then
  	if ! grep -Eq '^alias eth0 xennet$' "${conf}" ; then
  	    # Required module alias not present!
  	    return 0
  	fi
      else
  	if grep -Eq '^[^#]*eth0' "${conf}" ; then
  	    # Module alias shouldn't be present as driver is kernel resident!
  	    return 0 
  	fi
      fi
      if [ X"${REQUIRE_XENBLK_KO}" = "Xyes" ] ; then
  	if ! grep -Eq '^alias scsi_hostadapter xenblk$' "${conf}" ; then
  	    # Required module alias not present!
  	    return 0
  	fi
      else
  	if grep -Eq '^[^#]*scsi_hostadapter' "${conf}" ; then
  	    # Module alias shouldn't be present as driver is kernel resident!
  	    return 0 
  	fi
      fi
  
      # no need to update modules configuration
      return 1
  }
  
  update_modules_configuration()
  {
      if [ -f "/etc/modprobe.conf" ] ; then
  	conf="/etc/modprobe.conf"
      elif [ -f "/etc/modules.conf" ] ; then
  	conf="/etc/modules.conf"
      else
  	return 1
      fi
  
      echo "Updating ${conf}, original saved in ${conf}.bak"
      cp "${conf}" "${conf}.bak"
  
      # Flush lines concerning PV modules
      grep -Ev '\beth0\b|\bscsi_hostadapter\b' "${conf}.bak" >"${conf}" || true
  
      # Add lines to alias any PV modules needed
      if [ X"${REQUIRE_XENNET_KO}" = "Xyes" ] ; then
  	echo 'alias eth0 xennet' >>"${conf}"
      fi
      if [ X"${REQUIRE_XENBLK_KO}" = "Xyes" ] ; then
  	echo 'alias scsi_hostadapter xenblk' >>"${conf}"
      fi
  
      return 0
  }
  
  update_grub_configuration()
  {
      if [ -f "/boot/grub/menu.lst" ] ; then
  	conf=$(readlink -f "/boot/grub/menu.lst")
      elif [ -f "/boot/grub/grub.conf" ] && [ ! -L "/boot/grub/grub.conf" ] ; then
  	conf=$(readlink -f "/boot/grub/grub.conf")
      else
  	echo "No grub configuration found. Not updating"
  	return 1
      fi
  
      cmdline=$(cat /proc/cmdline)
      if [ -z "${cmdline}" ] ; then
  	echo "No kernel command line found. Not updating grub configuration."
  	return 1
      fi
      
      echo "Updating ${conf}, original saved in ${conf}.bak"
      cp "${conf}" "${conf}.bak"
  
      # Correct kernel command line.
      echo "  * set kernel command line to \`${cmdline}'."
      
  
      # Ensure kernel initrd and module lines include /boot/ if it is
      # not a separate filesystem.
      root_stat=$(stat --format='%d' --terse "/")
      boot_stat=$(stat --format='%d' --terse "/boot")
      if [ "${root_stat}" == "${boot_stat}" ] ; then 
  	echo "  * prepend /boot/ to kernel path."
  	rewrite_path="s;^\(\([^\#]*\|\)\(kernel\|initrd\|module\)\) \(/boot\)\?/\?;\1 /boot/;g"
      fi
  
      sed -e "s;^\(\([^\#]*\|\)kernel [^ ]*\) .*;\1 ${cmdline};g ; ${rewrite_path}" \
  	<"${conf}.bak" >"${conf}"
  
      # Make sure there is an entry for the kernel pointed to by /boot/xenkernel
      if [ -L "/boot/xenkernel" ] && [ -x "/sbin/grubby" ] ; then
  	kernel=$(readlink -f "/boot/xenkernel")
  	initrd=$(readlink -f "/boot/xeninitrd")
  	k="$(basename ${kernel} | sed -e 's/vmlinu.-//g')"
  	echo "  * add entry for ${k} (/boot/xenkernel)."
  	[ -n "${initrd}" ] && INITRD="--initrd ${initrd}"
  	/sbin/grubby --add-kernel=${kernel} $INITRD \
  	    --copy-default --make-default --title="${k}"
      fi
  
      echo
  
      return 0
  }
  
  update_vmlinuz_symlink()
  {
      local symlink=$(readlink -f "/boot/vmlinuz")
  
      case ${symlink} in
  	/boot/xenu-linux-*)
  	    ;;
  	*)
  	    echo "\`/boot/vmlinuz' does not point to a Xen kernel. Leaving."
  	    return 1
  	    ;;
      esac
  
      local version=${symlink/\/boot\/xenu-linux-}
  
      mv -v "/boot/vmlinuz" "/boot/vmlinuz-xenu-${version}"
  
      if [ -L "/boot/initrd.img" ] && \
  	[ "$(readlink -f /boot/initrd.img)" = "/boot/initrd.img-${version}" ] ; then
  	mv -v "/boot/initrd.img" "/boot/initrd.img-xenu-${version}"
      fi
  }
  
  install_rpms()
  {
      if [ -n "${XGU}" ] ; then
  	rpm -Uvh ${XGU}
      fi
  
      if [ -n "${MKINITRD}" ] ; then
  	rpm -Fvh --replacefiles --replacepkgs "${MKINITRD}"
      fi
  
      if [ -n "${ECRYPTFS_UTILS}" ] ; then
  	rpm -Fvh --replacefiles --replacepkgs "${ECRYPTFS_UTILS}"
      fi
  
      # Install not upgrade so that old kernel is retained.
      if [ -n "${KERNEL}" ] ; then
  	rpm -ivh "${KERNEL}"
  	version=$(rpm -qp --qf "%{V}-%{R}
  " "${KERNEL}")
  	if [ -f "/boot/vmlinuz-${version}xenU" ] && [ -x "/sbin/grubby" ] ; then
  	    echo "Making kernel ${version}xenU"
  	    echo "the default in grub configuration."
  	    /sbin/grubby --set-default="/boot/vmlinuz-${version}xenU"
  	    echo ""
  	fi
      fi
      echo ""
  }
  
  install_debs()
  {
      dpkg -i ${KERNEL} ${MKINITRD} ${XGU}
  
      echo ""
  }
  
  install_coreos()
  {
      echo "Installing the agent..."
      mkdir -p /usr/share/oem/xs/
      cp -f ${DATADIR}/xe-daemon \
            ${DATADIR}/xe-linux-distribution \
            ${DATADIR}/xe-update-guest-attrs /usr/share/oem/xs/
      cp -f ${DATADIR}/xen-vcpu-hotplug.rules /etc/udev/rules.d/
      cp -f ${DATADIR}/xe-linux-distribution.service /etc/systemd/system/
      systemctl enable /etc/systemd/system/xe-linux-distribution.service
      echo "Installation complete."
      systemctl start xe-linux-distribution.service
  }
  
  case "${os_distro}" in

      rhel|centos|oracle|fedora)         select_pkgs_rhel ;;
      scientific|neokylin|asianux|turbo) select_pkgs_rhel ;;
      sles|"suse linux")                 select_pkgs_sles ;;
      debian|ubuntu|linx|yinhe)          select_pkgs_debian ;;
      xe-ddk|xe-sdk)                     select_pkgs_xe ;;
      CoreOS)                            select_pkgs_coreos ;;

      *)                  failure "Unknown Linux distribution \`${os_distro}'." ;;
  esac
  
  if [ -n "${KERNEL}" ] ; then
      for K in ${KERNEL} ; do
  	if [ ! -f "${K}" ] ; then
  	    echo "Warning: kernel ${K} not found."
  	    echo ""
  	    KERNEL=""
  	fi
      done
  fi
  if [ -n "${MKINITRD}" -a ! -f "${MKINITRD}" ] ; then
      echo "Warning: mkinitrd ${MKINITRD} not found."
      echo ""
      MKINITRD=""
  fi
  if [ -n "${ECRYPTFS_UTILS}" ] ; then
      for E in ${ECRYPTFS_UTILS} ; do
  	if [ ! -f "${E}" ] ; then
  	    echo "Warning: ecryptfs-utils ${E} not found."
  	    echo ""
  	    ECRYPTFS_UTILS=""
  	fi
      done
  fi
  if [ -n "${XGU}" ] ; then
      for P in ${XGU} ; do
  	if [ ! -f "${P}" ] ; then
  	    echo "Warning: xe-guest-utilities ${P} not found."
  	    XGU=""
  	fi
      done
  fi
  if [ -z "${XGU}" ] ; then
      echo ""
      echo "Certain guest features will not be active until a version of "
      echo "xe-guest-utilities is installed."
      echo ""
  fi
  
  if [ -z "${KERNEL}" -a -z "${MKINITRD}" -a -z "${XGU}" -a -z "${ECRYPTFS_UTILS}" ] ; then
      echo "No updates required to this Virtual Machine."
      exit 0
  fi
  
  echo "The following changes will be made to this Virtual Machine:"
  
  if [ -n "${KERNEL}" -a -L "/boot/xenkernel" ] ||
     [ -n "${KERNEL}" -a -L "/boot/vmlinuz" ] ; then
      echo "  * grub configuration update."
      echo "  * remove legacy kernel and initrd symbolic links."
      update_grub=1
  else
      update_grub=0
  fi
  
  if update_modules_configuration_required ; then
      echo "  * modules configuration update."
      update_modules=1
  else
      update_modules=0
  fi
  
  if update_lvm_configuration_required ; then
      echo "  * lvm configuration update."
      update_lvm=1
  else
      update_lvm=0
  fi
  
  if update_inittab_configuration_required ; then
      echo "  * update gettys in inittab."
      update_inittab=1
  else
      update_inittab=0
  fi
  
  if update_arp_notify_required ; then
      echo "  * update arp_notify sysctl."
      update_arp_notify=1
  else
      update_arp_notify=0
  fi
  
  echo "  * packages to be installed/upgraded:"
  for K in ${KERNEL}; do
      echo -e                           "    - $(basename ${K})"
  done
  [ -n "${MKINITRD}" ] && echo -e       "    - $(basename ${MKINITRD})"
  for E in ${ECRYPTFS_UTILS}; do
      echo -e                           "    - $(basename ${E})"
  done
  for P in ${XGU}; do
      echo -e                           "    - $(basename ${P})"
  done
  echo ""
  
  if [ ${interactive} -gt 0 ] ; then
      while read -p "Continue? [y/n] " -n 1 ans ; do
  	echo
  	case "$ans" in
  	    Y|y)
  		break
  		;;
  	    N|n)
  		echo "Aborting."
  		exit 0
  		;;
  	    *)
  		echo "Invalid response \`$ans'"
  		;;
  	esac
      done
      echo
  fi
  
  set -e # Any failures from here onwards should be fatal
  
  if [ "${update_grub}" -gt 0 ] ; then
      update_grub_configuration
  
      # Remove /boot/xenkernel
      if [ -L "/boot/xenkernel" ] || [ -L "/boot/xeninitrd" ] || [ -L "/boot/vmlinuz" ] ; then
  	echo "Removing legacy boot kernel and initrd symbolic links."
  	[ -L "/boot/xenkernel" ] && mv -v "/boot/xenkernel" "/boot/xenkernel.bak"
  	[ -L "/boot/xeninitrd" ] && mv -v "/boot/xeninitrd" "/boot/xeninitrd.bak"
  	[ -L "/boot/vmlinuz" ] && update_vmlinuz_symlink
  	echo
      fi
  fi
  
  if [ "${update_modules}" -gt 0 ] ; then
      update_modules_configuration
  fi
  
  if [ "${update_lvm}" -gt 0 ] ; then
      update_lvm_configuration
  fi
  
  if [ "${update_inittab}" -gt 0 ] ; then
      update_inittab_configuration
  fi
  
  if [ "${update_arp_notify}" -gt 0 ] ; then
      update_arp_notify_configuration
  fi
  
  case ${GUEST_PKG_TYPE} in
      rpm) install_rpms ;;
      deb) install_debs ;;
      coreos) install_coreos ;;
  esac
  
  if [ -n "${KERNEL}" -o -n "${XGU}" ] ; then
      echo "You should now reboot this Virtual Machine."
  fi
  
  exit 0