#!/bin/sh
#
# iSCSI OCF resource agent
# Description: manage iSCSI disks (add/remove) using open-iscsi
#
# Copyright Dejan Muhamedagic <dejan@suse.de>
# (C) 2007 Novell Inc. All Rights Reserved.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of version 2 of the GNU General Public License as
# published by the Free Software Foundation.
#
# This program is distributed in the hope that it would be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
#
# Further, this software is distributed without any warranty that it is
# free of the rightful claim of any third person regarding infringement
# or the like.  Any license provided herein, whether implied or
# otherwise, applies only to this software file.  Patent licenses, if
# any, provided herein do not apply to combinations of this program with
# other software, or any other product whatsoever.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write the Free Software Foundation,
# Inc., 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
#
# See usage() and meta_data() below for more details...
#
# OCF instance parameters:
#	OCF_RESKEY_portal: the iSCSI portal address or host name (required)
#	OCF_RESKEY_target: the iSCSI target (required)
#	OCF_RESKEY_iscsiadm: iscsiadm program path (optional)
#	OCF_RESKEY_discovery_type: discovery type (optional; default: sendtargets)
#
# Initialization:

. ${OCF_ROOT}/resource.d/heartbeat/.ocf-shellfuncs

usage() {
  methods=`iscsi_methods`
  methods=`echo $methods | tr ' ' '|'`
  cat <<-!
	usage: $0 {$methods}

	$0 manages an iSCSI target

	The 'start' operation starts (adds) the iSCSI target.
	The 'stop' operation stops (removes) the iSCSI target.
	The 'status' operation reports whether the iSCSI target is connected
	The 'monitor' operation reports whether the iSCSI target is connected
	The 'validate-all' operation reports whether the parameters are valid
	The 'methods' operation reports on the methods $0 supports

	!
}

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

<longdesc lang="en">
OCF Resource Agent for iSCSI. Add (start) or remove (stop) iSCSI
targets.
</longdesc>
<shortdesc lang="en">iscsi resource agent</shortdesc>

<parameters>

<parameter name="portal" unique="0" required="1">
<longdesc lang="en">
The iSCSI portal address in the form: {ip_address|hostname}[":"port]
</longdesc>
<shortdesc lang="en">portal</shortdesc>
<content type="string" default="" />
</parameter>

<parameter name="target" unique="1" required="1">
<longdesc lang="en">
The iSCSI target.
</longdesc>
<shortdesc lang="en">target</shortdesc>
<content type="string" default="" />
</parameter>

<parameter name="discovery_type" unique="0" required="0">
<longdesc lang="en">
Discovery type. Currently, with open-iscsi, only the sendtargets
type is supported.
</longdesc>
<shortdesc lang="en">discovery_type</shortdesc>
<content type="string" default="sendtargets" />
</parameter>

<parameter name="iscsiadm" unique="0" required="0">
<longdesc lang="en">
iscsiadm program path.
</longdesc>
<shortdesc lang="en">iscsiadm</shortdesc>
<content type="string" default="" />
</parameter>

<parameter name="udev" unique="0" required="0">
<longdesc lang="en">
If the next resource depends on the udev creating a device then
we wait until it is finished. On a normally loaded host this
should be done quickly, but you may be unlucky. If you are not
using udev set this to "no", otherwise we will spin in a loop
until a timeout occurs.
</longdesc>
<shortdesc lang="en">udev</shortdesc>
<content type="string" default="yes" />
</parameter>

</parameters>

<actions>
<action name="start" timeout="120" />
<action name="stop" timeout="120" />
<action name="status" timeout="30" />
<action name="monitor" depth="0" timeout="30" interval="120" start-delay="10" />
<action name="validate-all" timeout="5" />
<action name="methods" timeout="5" />
<action name="meta-data" timeout="5" />
</actions>
</resource-agent>
END
}

iscsi_methods() {
  cat <<-!
	start
	stop
	status
	monitor
	validate-all
	methods
	meta-data
	usage
	!
}

#
# open-iscsi interface
#

open_iscsi_daemon() {
	if ps -e -o cmd | grep -qs '[i]scsid'; then
		return 0
	else
		ocf_log err "iscsid not running; please start open-iscsi utilities"
		return 1
	fi
}
open_iscsi_setup() {
	discovery=open_iscsi_discovery
	add_disk=open_iscsi_add
	remove_disk=open_iscsi_remove
	disk_status=open_iscsi_status
	iscsiadm=${OCF_RESKEY_iscsiadm:-"iscsiadm"}

	which $iscsiadm >/dev/null || {
		ocf_log err "iscsiadm not available; please set OCF_RESKEY_iscsiadm"
		return $OCF_ERR_INSTALLED
	}
	open_iscsi_daemon ||
		return $OCF_ERR_INSTALLED
}

#
# discovery return codes:
#   0: ok (variable portal set)
#   1: target not found
#   2: target found but can't connect it unambigously
#   3: iscsiadm returned error

open_iscsi_discovery() {
	output=`$iscsiadm -m discovery -p $OCF_RESKEY_portal -t $discovery_type`
	if [ $? -ne 0 -o x = "x$output" ]; then
		[ x != "x$output" ] && echo "$output"
		return 3
	fi
	portal=`echo "$output" |
		awk -v target="$OCF_RESKEY_target" '
		$NF==target{
			if( NF==3 ) portal=$2; # sles compat mode
			else portal=$1;
			sub(",.*","",portal);
			print portal;
		}'`

	case `echo "$portal" | wc -w` in
	0) #target not found
		echo "$output"
		ocf_log err "target $OCF_RESKEY_target not found at portal $OCF_RESKEY_portal"
		return 1
	;;
	1) #we're ok
		return 0
	;;
	*) # handle multihome hosts reporting multiple portals
		for p in $portal; do
			if [ "$OCF_RESKEY_portal" = "$p" ]; then
				portal="$OCF_RESKEY_portal"
				return 0
			fi
		done
		echo "$output"
		ocf_log err "sorry, can't handle multihomed hosts unless you specify the portal exactly"
		return 2
	;;
	esac
}
open_iscsi_add() {
	$iscsiadm -m node -p $1 -T $2 -l
}
open_iscsi_remove() {
	$iscsiadm -m node -p $1 -T $2 -u
}
open_iscsi_status() {
	$iscsiadm -m session 2>/dev/null | grep -qs "$2$"
}

#
# NB: this is udev specific!
#
wait_for_udev() {
	dev=/dev/disk/by-path/ip-$portal-iscsi-$OCF_RESKEY_target
	while :; do
		ls $dev* >/dev/null 2>&1 && break
		ocf_log warning "waiting for udev to create $dev" 
		sleep 1
	done
}
iscsi_status() {
	if $disk_status $portal $OCF_RESKEY_target; then
		return $OCF_SUCCESS
	else
		return $OCF_NOT_RUNNING
	fi
}
iscsi_start() {
	if iscsi_status; then
		ocf_log info "iscsi $portal $OCF_RESKEY_target already running"
		return $OCF_SUCCESS
	else
		$add_disk $portal $OCF_RESKEY_target ||
			return $OCF_ERR_GENERIC
		case "$OCF_RESKEY_udev" in
		[Yy]es) wait_for_udev ||
			return $OCF_ERR_GENERIC
		;;
		*) ;;
		esac
		if iscsi_status; then
			return $OCF_SUCCESS
		else
			return $OCF_ERR_GENERIC
		fi
	fi
}
iscsi_stop() {
	if iscsi_status; then
		$remove_disk $portal $OCF_RESKEY_target ||
			return $OCF_ERR_GENERIC
		if iscsi_status; then
			return $OCF_ERR_GENERIC
		else
			return $OCF_SUCCESS
		fi
	else
		ocf_log info "iscsi $portal $OCF_RESKEY_target already stopped"
		return $OCF_SUCCESS
	fi
}

iscsi_monitor() {
	if $disk_status $portal $OCF_RESKEY_target; then
		return $OCF_SUCCESS
    else
		return $OCF_NOT_RUNNING
    fi
}

#
#	'main' starts here...
#

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

# These operations don't require OCF instance parameters to be set
case "$1" in
	meta-data)	meta_data
		exit $OCF_SUCCESS;;
	usage) usage
		exit $OCF_SUCCESS;;
	methods) iscsi_methods
		exit $OCF_SUCCESS;;
esac

if [ x = "x$OCF_RESKEY_target" ]; then
	ocf_log err "no target attribute"
	exit $OCF_ERR_ARGS
fi

case `uname` in
Linux) setup=open_iscsi_setup
;;
*) ocf_log info "platform `uname` may not be supported"
	setup=open_iscsi_setup
;;
esac

LSB_STATUS_STOPPED=3
$setup
rc=$?
if [ $rc -ne 0 ]; then
	ocf_log info "iscsi initiator utilities not installed or not setup"
	case "$1" in
		stop) exit $OCF_SUCCESS;;
		monitor) exit $OCF_NOT_RUNNING;;
		status) exit $LSB_STATUS_STOPPED;;
		*) exit $rc;;
	esac
fi

if [ `id -u` != 0 ]; then
	ocf_log err "$0 must be run as root"
	exit $OCF_ERR_PERM
fi

discovery_type=${OCF_RESKEY_discovery_type:-"sendtargets"}
udev=${OCF_RESKEY_udev:-"yes"}
$discovery  # discover and setup the real portal string (address)
case $? in
0) ;;
1) [ "$1" = stop ] && exit $OCF_SUCCESS
   [ "$1" = monitor ] && exit $OCF_NOT_RUNNING
   [ "$1" = status ] && exit $LSB_STATUS_STOPPED
   exit $OCF_ERR_GENERIC
;;
[23]) exit $OCF_ERR_GENERIC;;
esac

# which method was invoked?
case "$1" in
	start)	iscsi_start
	;;
	stop)	iscsi_stop
	;;
	status)	if iscsi_status
		then
		  echo iscsi target $OCF_RESKEY_target running
		  exit $OCF_SUCCESS
		else
		  echo iscsi target $OCF_RESKEY_target stopped
		  exit $OCF_NOT_RUNNING
		fi
		;;
	monitor)	iscsi_status
	;;
	validate-all)	# everything already validated
		# just exit successfully here.
		exit $OCF_SUCCESS;;
	*)		iscsi_methods
		exit $OCF_ERR_UNIMPLEMENTED;;
esac

#
# vim:tabstop=4:shiftwidth=4:textwidth=0:wrapmargin=0
