#!/bin/bash
#
#
# 	SCSTTarget OCF RA. Exports and manages iSCSI SCST targets.
#
#   (c) 2012 Riccardo Bicelli
#                 and Linux-HA contributors
#
# 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.
#

#######################################################################
# Initialization:
: ${OCF_FUNCTIONS_DIR=${OCF_ROOT}/lib/heartbeat}
. ${OCF_FUNCTIONS_DIR}/ocf-shellfuncs

# Set portal to none by default
OCF_RESKEY_portals_default="none"
: ${OCF_RESKEY_portals=${OCF_RESKEY_portals_default}}


# Lockfile, used for selecting a target ID
LOCKFILE=${HA_RSCTMP}/SCSTTarget-${OCF_RESKEY_implementation}.lock
ISCSI_DAEMON="/usr/local/sbin/iscsi-scstd"
SYSFS_PATH="/sys/kernel/scst_tgt/targets/iscsi"
SCST_BASE="/sys/kernel/scst_tgt"
ISCSI_BASE="${SCST_BASE}/targets/iscsi"
#######################################################################

meta_data() {
	cat <<END
<?xml version="1.0"?>
<!DOCTYPE resource-agent SYSTEM "ra-api-1.dtd">
<resource-agent name="SCSTTarget" version="0.1">
<version>1.0</version>

<longdesc lang="en">
Manages SCST iSCSI targets. An iSCSI target is a collection of SCSI Logical
Units (LUs) exported via a daemon that speaks the iSCSI protocol.
</longdesc>
<shortdesc lang="en">SCST iSCSI target export agent</shortdesc>

<parameters>

<parameter name="iqn" required="1" unique="1">
<longdesc lang="en">
The target iSCSI Qualified Name (IQN). Should follow the conventional
"iqn.yyyy-mm.&lt;reversed domain name&gt;[:identifier]" syntax.
</longdesc>
<shortdesc lang="en">iSCSI target IQN</shortdesc>
<content type="string" />
</parameter>

<parameter name="portals" required="0" unique="0">
<longdesc lang="en">
iSCSI network portal addresses. Not supported by all
implementations. If unset, the default is to create one portal that
listens on all IP addresses.
</longdesc>
<shortdesc lang="en">iSCSI portal addresses</shortdesc>
<content type="string" default="${OCF_RESKEY_portals_default}"/>
</parameter>

<parameter name="allowed_initiators" required="0" unique="0">
<longdesc lang="en">
TODO: Allowed initiators. A space-separated list of initiators allowed to
connect to this target. Initiators may be listed in any syntax
the target implementation allows. If this parameter is empty or
not set, access to this target will be allowed from any initiator.
</longdesc>
<shortdesc lang="en">TODO: List of iSCSI initiators allowed to connect
to this target</shortdesc>
<content type="string" default=""/>
</parameter>

<parameter name="incoming_username" required="0" unique="1">
<longdesc lang="en">
A username used for incoming initiator authentication. If unspecified,
allowed initiators will be able to log in without authentication.
</longdesc>
<shortdesc lang="en">Incoming account username</shortdesc>
<content type="string"/>
</parameter>

<parameter name="incoming_password" required="0" unique="0">
<longdesc lang="en">
A password used for incoming initiator authentication.
</longdesc>
<shortdesc lang="en">Incoming account password</shortdesc>
<content type="string"/>
</parameter>

<parameter name="additional_parameters" required="0" unique="0">
<longdesc lang="en">
Additional target parameters. A space-separated list of "name=value"
pairs which will be passed through to the iSCSI daemon's management
interface. The supported parameters are implementation
dependent. Neither the name nor the value may contain whitespace.
</longdesc>
<shortdesc lang="en">List of iSCSI target parameters</shortdesc>
<content type="string" />
</parameter>

</parameters>

<actions>
<action name="start"        timeout="10" />
<action name="stop"         timeout="180" />
<action name="status "      timeout="10" interval="10" depth="0" />
<action name="monitor"      timeout="10" interval="10" depth="0" />
<action name="meta-data"    timeout="5" />
<action name="validate-all"   timeout="10" />
</actions>
</resource-agent>
END
}


l_load_module () {
	n=`lsmod | grep -c "^$1 "`
	if [ $n -gt 0 ];
	then
		return 0
	else
		modprobe $1> /dev/null 2>&1 || return 1
		return 0
	fi
}

l_start_service () {
		local running

		# Handler modules are loaded in LUN resource agent

		# Check if modules are loaded
		if [ ! -d ${SYSFS_PATH} ]; then
			ocf_log info "Loading scst Modules"
			l_load_module scst || return 1
			l_load_module iscsi_scst || return 1

			#Not critical modules, not unloaded on stop.
			l_load_module crc32c
			l_load_module crc32c_intel
		fi

		# Start Daemon
		if [ ! "$(pidof ${ISCSI_DAEMON})" ]; then
			ocf_run $ISCSI_DAEMON || return 1
			ocf_run scstadmin -force -noprompt -clear_config >/dev/null 2>&1
		fi
		return 0
}

l_stop_service () {
	#Stop SCST Services, if there are no targets active.
	local TARGET_NOT_PRESENT=true

	#Are there targets active?
	for i in $( ls "${ISCSI_BASE}" ) ; do
	if [ -d "${ISCSI_BASE}/${i}" ]; then
		ocf_log warn "Found target running: ${i}"
		TARGET_NOT_PRESENT=false
	fi
	done

	#Close sessions
	for i in `/bin/ls ${ISCSI_BASE}/${OCF_RESKEY_iqn}/sessions`; do
		ocf_log warn "Force closing session to initiator ${i}"
        	echo "1" > "${ISCSI_BASE}/${OCF_RESKEY_iqn}/sessions/${i}/force_close"
    	done

	#Stop process and unload modules
	if $TARGET_NOT_PRESENT ; then
		ocf_log warn "Daemon not required, stopping ..."
		pkill -TERM -f $ISCSI_DAEMON
		rmmod iscsi_scst
		rmmod scst
	fi
}

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

Expects to have a fully populated OCF RA-compliant environment set.
END
}

SCSTTarget_start() {
    SCSTTarget_monitor
    if [ $? =  $OCF_SUCCESS ]; then
	return $OCF_SUCCESS
    fi

    local param
    local name
    local value
    local initiator

		# Start Service
		l_start_service
		# Set incoming username and password globally
		if [ "${OCF_RESKEY_incoming_username}" != "" ]; then
			echo "add_attribute IncomingUser ${OCF_RESKEY_incoming_username} ${OCF_RESKEY_incoming_password}" > ${ISCSI_BASE}/mgmt
			if [ $? -ne 0 ]; then
				ocf_log warn "Unable to set CHAP Authentication!"
			fi
		fi

		ocf_log info "target ${OCF_RESKEY_iqn}: Starting..."

		# Create Target
		echo "add_target ${OCF_RESKEY_iqn}" > ${ISCSI_BASE}/mgmt || exit $OCF_ERR_GENERIC

		# Set Allowed Portals
		if [ "${OCF_RESKEY_portals}" != "none" ]; then
			for param in ${OCF_RESKEY_portals}; do
			ocf_log info "Adding allowed portal ${param} to target ${OCF_RESKEY_iqn}"
			echo "add_target_attribute ${OCF_RESKEY_iqn} allowed_portal ${param}" > ${ISCSI_BASE}/mgmt
			if [ $? -ne 0 ]; then
				ocf_log warn "Unable to set Allowed Portal!"
			fi
	  		done
		fi

		# Set incoming username and password
		if [ "${OCF_RESKEY_incoming_username}" != "" ]; then
			echo "add_target_attribute ${OCF_RESKEY_iqn} IncomingUser ${OCF_RESKEY_incoming_username} ${OCF_RESKEY_incoming_password}" > ${ISCSI_BASE}/mgmt
			if [ $? -ne 0 ]; then
				ocf_log warn "Unable to set CHAP Authentication!"
			fi
		fi

		ocf_log info "Enabling target ${OCF_RESKEY_iqn}"
		# Enable iSCSI Target
		echo 1 > "${ISCSI_BASE}/enabled" || exit $OCF_ERR_GENERIC

		ocf_log debug "SCST target ${OCF_RESKEY_iqn}: Started."

		#Debugging purpose
		#scstadmin -write_config /tmp/scst.conf.start
    return $OCF_SUCCESS
}

SCSTTarget_stop() {
    SCSTTarget_monitor

    if [ $? =  $OCF_SUCCESS ]; then
	local param
	ocf_log info "target ${OCF_RESKEY_iqn}: Stopping..."

	# Check if there are connected luns
    	for i in $( ls "${ISCSI_BASE}/${OCF_RESKEY_iqn}/luns" ) ; do
    		if [ -d "${ISCSI_BASE}/${OCF_RESKEY_iqn}/luns/${i}" ]; then
		ocf_log err "Unable to stop target ${OCF_RESKEY_iqn}: lun ${i} connected!"
		exit $OCF_ERR_GENERIC
    		fi
    	done

	# Disable Target
	ocf_log info "disabling target ${OCF_RESKEY_iqn}"
	echo 0 > ${ISCSI_BASE}/${OCF_RESKEY_iqn}/enabled || exit $OCF_ERR_GENERIC

	#Remove Target
	ocf_log info "deleting target ${OCF_RESKEY_iqn}"
	echo "del_target ${OCF_RESKEY_iqn}" > ${ISCSI_BASE}/mgmt
	if [ $? -ne 0 ]; then
		ocf_log err "Unable to delete Target ${OCF_RESKY_iqn}"
		exit $OCF_ERR_GENERIC
	fi
	#Debugging purpose
	#scstadmin -write_config /tmp/scst.conf.stop

	#Check if other targets are running, then stop service and unload modules
	l_stop_service
	ocf_log info "target ${OCF_RESKEY_iqn}: Stopped."
    fi

    return $OCF_SUCCESS
}

SCSTTarget_monitor() {
	if [ -d "${SYSFS_PATH}/${OCF_RESKEY_iqn}" ]; then
		return $OCF_SUCCESS
	else
		return $OCF_NOT_RUNNING
	fi
}

SCSTTarget_validate() {
    # Do we have all required variables?
    local required_vars
	    required_vars="iqn"
    for var in ${required_vars}; do
	param="OCF_RESKEY_${var}"
	if [ -z "${!param}" ]; then
	    ocf_log error "Missing resource parameter \"$var\"!"
	    exit $OCF_ERR_CONFIGURED
	fi
    done

    if ! ocf_is_probe; then
		check_binary scstadmin
    fi

    return $OCF_SUCCESS
}


case $1 in
  meta-data)
	meta_data
	exit $OCF_SUCCESS
	;;
  usage|help)
	SCSTTarget_usage
	exit $OCF_SUCCESS
	;;
esac

# Everything except usage and meta-data must pass the validate test
SCSTTarget_validate

case $__OCF_ACTION in
start)		SCSTTarget_start;;
stop)		SCSTTarget_stop;;
monitor|status)	SCSTTarget_monitor;;
#reload)		ocf_log err "Reloading..."
#	        SCSTTarget_start
#		;;
validate-all)	;;
*)		SCSTTarget_usage
		exit $OCF_ERR_UNIMPLEMENTED
		;;
esac
rc=$?
ocf_log debug "${OCF_RESOURCE_INSTANCE} $__OCF_ACTION : $rc"
exit $rc