#!/bin/bash
#
# Name     ManageRAID
# Author   Matthias Dahl, m.dahl@designassembly.de
# License  GPL version 2
#
# (c) 2006 The Design Assembly GmbH.
#
#
# WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
#
# This resource agent is most likely function complete but not error free. Please
# consider it BETA quality for the moment until it has proven itself stable...
#
# USE AT YOUR OWN RISK.
#
# WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
#
#
# partly based on/inspired by original Heartbeat2 OCF resource agents
#
# Description
#
# Manages starting, mounting, unmounting, stopping and monitoring of RAID devices
# which are preconfigured in /etc/conf.d/HB-ManageRAID.
#
# 
# Created  11. Sep 2006
# Updated  18. Sep 2006
#
# rev. 1.00.2
#
# Changelog
#
# 18/Sep/06 1.00.1 more cleanup
# 12/Sep/06 1.00.1 add more functionality
#                  add sanity check for config parameters
#                  general cleanup all over the place
# 11/Sep/06 1.00.0 it's alive... muahaha... ALIVE... :-)
#
#
# TODO
#
#   - check if at least one disk out of PREFIX_LOCALDISKS is still active
#     in RAID otherwise consider RAID broken and stop it.
#
#     The reason behind this: consider a RAID-1 which contains iSCSI devices
#     shared over Ethernet which get dynamically added/removed to/from the RAID.
#     Once all local disks have failed and only those iSCSI disks remain, the RAID
#     should really stop to prevent bad performance and possible data loss.
# 

###
: ${OCF_FUNCTIONS_DIR=${OCF_ROOT}/resource.d/heartbeat}
. ${OCF_FUNCTIONS_DIR}/.ocf-shellfuncs
###

# required utilities

# required files/devices
RAID_MDSTAT=/proc/mdstat

#
# check_file()
#
check_file ()
{
    if [[ ! -e $1 ]]; then
        ocf_log err "setup problem: file $1 does not exist."
        exit $OCF_ERR_GENERIC
    fi
}

#
# usage()
#
usage()
{
	cat <<-EOT
	usage: $0 {start|stop|status|monitor|validate-all|usage|meta-data}
	EOT
}

#
# meta_data()
#
meta_data()
{
	cat <<END
<?xml version="1.0"?>
<!DOCTYPE resource-agent SYSTEM "ra-api-1.dtd">
<resource-agent name="ManageRAID">
  <version>1.00.2</version>

  <longdesc lang="en">
    Manages starting, stopping and monitoring of RAID devices which
    are preconfigured in /etc/conf.d/HB-ManageRAID.
  </longdesc>

  <shortdesc lang="en">Manages RAID devices</shortdesc>

  <parameters>
    <parameter name="raidname" unique="0" required="1">
      <longdesc lang="en">
        Name (case sensitive) of RAID to manage. (preconfigured in /etc/conf.d/HB-ManageRAID)
      </longdesc>
      <shortdesc lang="en">RAID name</shortdesc>
      <content type="string" default="" />
    </parameter>
  </parameters>

  <actions>
    <action name="start" timeout="75" />
    <action name="stop" timeout="75" />
    <action name="status" depth="0" timeout="10" interval="10" />
    <action name="monitor" depth="0" timeout="10" interval="10" />
    <action name="validate-all" timeout="5" />
    <action name="meta-data" timeout="5" />
  </actions>
</resource-agent>
END
}

#
# start_raid()
#
start_raid()
{
  declare -i retcode

  status_raid
  retcode=$?
  if [[ $retcode == $OCF_SUCCESS ]]; then
    return $OCF_SUCCESS
  elif [[ $retcode != $OCF_NOT_RUNNING ]]; then
    return $retcode
  fi

  for ldev in ${RAID_LOCALDISKS[@]}; do
    if [[ ! -b $ldev ]]; then
      ocf_log err "$ldev is not a (local) block device."
      return $OCF_ERR_ARGS
    fi
  done

  $MDADM -A $RAID_DEVPATH -a yes -u ${!RAID_UUID} ${RAID_LOCALDISKS[@]} &> /dev/null
  if [[ $? != 0 ]]; then
    ocf_log err "starting ${!RAID_DEV} with ${RAID_LOCALDISKS[@]} failed."
    return $OCF_ERR_GENERIC
  fi

  $MOUNT -o ${!RAID_MOUNTOPTIONS} $RAID_DEVPATH ${!RAID_MOUNTPOINT} &> /dev/null
  if [[ $? != 0 ]]; then
    $MDADM -S $RAID_DEVPATH &> /dev/null
    
    if [[ $? != 0 ]]; then
      ocf_log err "mounting ${!RAID_DEV} to ${!RAID_MOUNTPOINT} failed as well as stopping the RAID itself."
    else
      ocf_log err "mounting ${!RAID_DEV} to ${!RAID_MOUNTPOINT} failed. RAID stopped again."
    fi

    return $OCF_ERR_GENERIC
  fi

  return $OCF_SUCCESS
}

#
# stop_raid()
#
stop_raid()
{
  status_raid
  if [[ $? == $OCF_NOT_RUNNING ]]; then
    return $OCF_SUCCESS
  fi

  $UMOUNT ${!RAID_MOUNTPOINT} &> /dev/null
  if [[ $? != 0 ]]; then
    ocf_log err "unmounting ${!RAID_MOUNTPOINT} failed. not stopping ${!RAID_DEV}!"
    return $OCF_ERR_GENERIC
  fi

  $MDADM -S $RAID_DEVPATH &> /dev/null
  if [[ $? != 0 ]]; then
    ocf_log err "stopping RAID ${!RAID_DEV} failed."
    return $OCF_ERR_GENERIC
  fi

  return $OCF_SUCCESS
}

#
# status_raid()
#
status_raid()
{ 
  declare -i retcode_raidcheck
  declare -i retcode_uuidcheck

  $CAT $RAID_MDSTAT | $GREP -e "${!RAID_DEV}[\ ]*:[\ ]*active" &> /dev/null
  if [[ $? != 0 ]]; then
    return $OCF_NOT_RUNNING
  fi
 
  if [[ ! -e $RAID_DEVPATH ]]; then
    return $OCF_ERR_GENERIC
  fi

  $MDADM --detail -t $RAID_DEVPATH &> /dev/null
  retcode_raidcheck=$?
  $MDADM --detail -t $RAID_DEVPATH | $GREP -qEe "^[\ ]*UUID[\ ]*:[\ ]*${!RAID_UUID}" &> /dev/null
  retcode_uuidcheck=$?

  if [[ $retcode_raidcheck > 3 ]]; then
    ocf_log err "mdadm returned error code $retcode_raidcheck while checking ${!RAID_DEV}."
    return $OCF_ERR_GENERIC
  elif [[ $retcode_raidcheck == 3 ]]; then
    ocf_log err "${!RAID_DEV} has failed."
    return $OCF_ERR_GENERIC
  elif [[ $retcode_raidcheck < 3 && $retcode_uuidcheck != 0  ]]; then
    ocf_log err "active RAID ${!RAID_DEV} and configured UUID (!$RAID_UUID) do not match."
    return $OCF_ERR_GENERIC
  fi

  $MOUNT | $GREP -e "$RAID_DEVPATH on ${!RAID_MOUNTPOINT}" &> /dev/null
  if [[ $? != 0 ]]; then
    ocf_log err "${!RAID_DEV} seems to be no longer mounted at ${!RAID_MOUNTPOINT}"
    return $OCF_ERR_GENERIC
  fi

  return $OCF_SUCCESS
}    

#
# validate_all_raid()
#
validate_all_raid()
{
  #
  # since all parameters are checked every time ManageRAID is
  # invoked, there not much more to check...
  #
  # status_raid should cover the rest.
  # 
  declare -i retcode

  status_ve
  retcode=$?

  if [[ $retcode != $OCF_SUCCESS && $retcode != $OCF_NOT_RUNNING ]]; then
    return $retcode
  fi

  return $OCF_SUCCESS
}

if [ $# -ne 1 ]; then
  usage
  exit $OCF_ERR_ARGS
fi

case "$1" in
  meta-data)
	meta_data
	exit $OCF_SUCCESS
	;;
  usage) 
	usage
	exit $OCF_SUCCESS
	;;
  *)
	;;
esac

## required configuration
#
[ -f /etc/conf.d/HB-ManageRAID ] || {
	ocf_log err "/etc/conf.d/HB-ManageRAID missing"
	exit $OCF_ERR_INSTALLED
}
. /etc/conf.d/HB-ManageRAID
#
##

#
# check relevant environment variables for sanity and security
#

declare -i retcode_test
declare -i retcode_grep

$TEST -z "$OCF_RESKEY_raidname"
retcode_test=$?
echo "$OCF_RESKEY_raidname" | $GREP -qEe "^[[:alnum:]\_]+$"
retcode_grep=$?

if [[ $retcode_test != 1 || $retcode_grep != 0 ]]; then
  ocf_log err "OCF_RESKEY_raidname not set or invalid."
  exit $OCF_ERR_ARGS
fi

RAID_UUID=${OCF_RESKEY_raidname}_UUID

echo ${!RAID_UUID} | $GREP -qEe "^[[:alnum:]]{8}:[[:alnum:]]{8}:[[:alnum:]]{8}:[[:alnum:]]{8}$"
if [[ $? != 0 ]]; then
  ocf_log err "${OCF_RESKEY_raidname}_UUID is invalid."
  exit $OCF_ERR_ARGS
fi

RAID_DEV=${OCF_RESKEY_raidname}_DEV

echo ${!RAID_DEV} | $GREP -qEe "^md[0-9]+$"
if [[ $? != 0 ]]; then
  ocf_log err "${OCF_RESKEY_raidname}_DEV is invalid."
  exit $OCF_ERR_ARGS
fi

RAID_DEVPATH=/dev/${!RAID_DEV/md/md\/}
RAID_MOUNTPOINT=${OCF_RESKEY_raidname}_MOUNTPOINT

echo ${!RAID_MOUNTPOINT} | $GREP -qEe "^[[:alnum:]\/\_\"\ ]+$"
if [[ $? != 0 ]]; then
  ocf_log err "${OCF_RESKEY_raidname}_MOUNTPOINT is invalid."
  exit $OCF_ERR_ARGS
fi

RAID_MOUNTOPTIONS=${OCF_RESKEY_raidname}_MOUNTOPTIONS

echo ${!RAID_MOUNTOPTIONS} | $GREP -qEe "^[[:alpha:]\,]+$"
if [[ $? != 0 ]]; then
  ocf_log err "${OCF_RESKEY_raidname}_MOUNTOPTIONS is invalid."
  exit $OCF_ERR_ARGS
fi

RAID_LOCALDISKS=${OCF_RESKEY_raidname}_LOCALDISKS[@]
RAID_LOCALDISKS=( "${!RAID_LOCALDISKS}" )

if [[ ${#RAID_LOCALDISKS[@]} < 1 ]]; then
  ocf_log err "you have to specify at least one local disk."
  exit $OCF_ERR_ARGS
fi

#
# check that all relevant utilities are available
# 
check_binary $MDADM
check_binary $MOUNT
check_binary $UMOUNT
check_binary $GREP
check_binary $CAT
check_binary $TEST
check_binary echo


#
# check that all relevant devices are available
#
check_file $RAID_MDSTAT 

#
# finally... let's see what we are ordered to do :-)
#
case "$1" in
  start)
	start_raid
	;;
  stop)
	stop_raid
	;;
  status|monitor) 
	status_raid
	;;
  validate-all)
	validate_all_raid
	;;
  *)
	usage
	exit $OCF_ERR_UNIMPLEMENTED 
	;;
esac

exit $?

