#!/bin/sh
#
#	   OCF Resource Agent compliant script.
#	   Monitor the vitality of a local OpenVSwitch bond.
#
# 	Based on the work by Alexander Krauth.
#
#	Transfered from ethmonitor into ovsmonitor by Mathieu Grzybek.
#
# Copyright (c) 2017 Robert Euhus, Alexander Krauth, Lars Marowsky-Bré
#		Mathieu Grzybek
#					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.
#
#	 OCF parameters are as below
#
#	OCF_RESKEY_bond
#	OCF_RESKEY_bridge
#	OCF_RESKEY_multiplicator
#	OCF_RESKEY_name
#	OCF_RESKEY_repeat_count
#	OCF_RESKEY_repeat_interval
#	OCF_RESKEY_pktcnt_timeout
#
#######################################################################
# Initialization:

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

# Parameter defaults

OCF_RESKEY_bond_default=""
OCF_RESKEY_bridge_default=""
OCF_RESKEY_name_default=""
OCF_RESKEY_multiplier_default="1"
OCF_RESKEY_repeat_count_default="5"
OCF_RESKEY_repeat_interval_default="10"
OCF_RESKEY_pktcnt_timeout_default="5"
OCF_RESKEY_link_status_only_default="false"

: ${OCF_RESKEY_bond=${OCF_RESKEY_bond_default}}
: ${OCF_RESKEY_bridge=${OCF_RESKEY_bridge_default}}
: ${OCF_RESKEY_name=${OCF_RESKEY_name_default}}
: ${OCF_RESKEY_multiplier=${OCF_RESKEY_multiplier_default}}
: ${OCF_RESKEY_repeat_count=${OCF_RESKEY_repeat_count_default}}
: ${OCF_RESKEY_repeat_interval=${OCF_RESKEY_repeat_interval_default}}
: ${OCF_RESKEY_pktcnt_timeout=${OCF_RESKEY_pktcnt_timeout_default}}
: ${OCF_RESKEY_link_status_only=${OCF_RESKEY_link_status_only_default}}

#######################################################################

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

<longdesc lang="en">
Monitor the vitality of a local ovs bond.

You may set up this RA as a clone resource to monitor the network bonds on different nodes, with the same bond name.
This is not related to the IP address or the network on which a bond is configured.
You may use this RA to move resources away from a node, which has a faulty bond or prevent moving resources to such a node.
This gives you independent control of the resources, without involving cluster intercommunication. But it requires your nodes to have more than one network bond.

The resource configuration requires a monitor operation, because the monitor does the main part of the work.
In addition to the resource configuration, you need to configure some location constraints, based on a CIB attribute value.
The name of the attribute value is configured in the 'name' option of this RA.

Example constraint configuration using crmsh
location loc_connected_node my_resource_grp \
        rule $id="rule_loc_connected_node" -INF: ovsmonitor-bond-public eq 0

Example constraint configuration using pcs. Only allow 'my_resource' to run on nodes where eth0 ethernet device is available.
pcs constraint location my_resource rule score=-INFINITY ovsmonitor-bond-public ne 1

The ethmonitor works in 3 different modes to test the bond vitality.
1. call ovs-appctl to see if at least one of the bonding's link status is up (if link is down -> error)
2. call ovs-ofctl and watch the RX counter (if packages come around in a certain time -> success)
3. return error
</longdesc>
<shortdesc lang="en">Monitors ovs bonding bonds</shortdesc>

<parameters>
<parameter name="bond" unique="1" required="1">
<longdesc lang="en">
The name of the network bond which should be monitored (e.g. bond-public).
</longdesc>
<shortdesc lang="en">Bond bond name</shortdesc>
<content type="string" default="${OCF_RESKEY_bond_default}"/>
</parameter>

<parameter name="bridge" unique="1" required="1">
<longdesc lang="en">
The name of the ovs bridge that contains the bridge.
</longdesc>
<shortdesc lang="en">ovs bridge</shortdesc>
<content type="string" default="${OCF_RESKEY_bridge_default}"/>
</parameter>

<parameter name="name" unique="1">
<longdesc lang="en">
The name of the CIB attribute to set. This is the name to be used in the constraints. Defaults to "ovsmonitor-'bond_name'".
</longdesc>
<shortdesc lang="en">Attribute name</shortdesc>
<content type="string" default="${OCF_RESKEY_name_default}"/>
</parameter>

<parameter name="multiplier" unique="0" >
<longdesc lang="en">
Multiplier for the value of the CIB attriobute specified in parameter name.
</longdesc>
<shortdesc lang="en">Multiplier for result variable</shortdesc>
<content type="integer" default="${OCF_RESKEY_multiplier_default}"/>
</parameter>

<parameter name="repeat_count">
<longdesc lang="en">
Specify how often the bond will be monitored, before the status is set to failed. You need to set the timeout of the monitoring operation to at least repeat_count * repeat_interval
</longdesc>
<shortdesc lang="en">Monitor repeat count</shortdesc>
<content type="integer" default="${OCF_RESKEY_repeat_count_default}"/>
</parameter>

<parameter name="repeat_interval">
<longdesc lang="en">
Specify how long to wait in seconds between the repeat_counts.
</longdesc>
<shortdesc lang="en">Monitor repeat interval in seconds</shortdesc>
<content type="integer" default="${OCF_RESKEY_repeat_interval_default}"/>
</parameter>

<parameter name="pktcnt_timeout">
<longdesc lang="en">
Timeout for the RX packet counter. Stop listening for packet counter changes after the given number of seconds.
</longdesc>
<shortdesc lang="en">packet counter timeout</shortdesc>
<content type="integer" default="${OCF_RESKEY_pktcnt_timeout_default}"/>
</parameter>

<parameter name="link_status_only">
<longdesc lang="en">
Only report success based on link status. Do not perform RX counter related connectivity tests.
</longdesc>
<shortdesc lang="en">link status check only</shortdesc>
<content type="boolean" default="${OCF_RESKEY_link_status_only_default}" />
</parameter>

</parameters>
<actions>
<action name="start" timeout="60s" />
<action name="stop" timeout="20s" />
<action name="status" depth="0" timeout="60s" interval="10s" />
<action name="monitor" depth="0" timeout="60s" interval="10s" />
<action name="meta-data" timeout="5s" />
<action name="validate-all" timeout="20s" />
</actions>
</resource-agent>
END

	exit $OCF_SUCCESS
}

#
# Return true, if the bond exists
#
is_bond() {
	#
	# List bonds but exclude FreeS/WAN ipsecN virtual bonds
	#
	ovs-appctl bond/show $OCF_RESKEY_bond 1>/dev/null 2>&1
}

#
# Return true, if the bridge exists
#
is_bridge() {
	#
	# List bonds but exclude FreeS/WAN ipsecN virtual bonds
	#
	#ovs-appctl bond/show $OCF_RESKEY_bond 1>/dev/null 2>&1
	ovs-vsctl show|grep Bridge|grep -q $OCF_RESKEY_bridge
}


if_init() {
	local rc

	if [ X"$OCF_RESKEY_bond" = "X" ]; then
		ocf_exit_reason "Bond name (the bond parameter) is mandatory"
		exit $OCF_ERR_CONFIGURED
	fi

	if [ X"$OCF_RESKEY_bridge" = "X" ]; then
		ocf_exit_reason "Bridge name (the bridge parameter) is mandatory"
		exit $OCF_ERR_CONFIGURED
	fi

	BOND="$OCF_RESKEY_bond"
	BRIDGE="$OCF_RESKEY_bridge"

	if is_bond
	then
		if ! is_bridge
		then
			ocf_exit_reason "Bridge $OCF_RESKEY_bond does not exist"
	 		exit $OCF_ERR_CONFIGURED;
		fi
	else
		ocf_exit_reason "Bond $OCF_RESKEY_bond does not exist"
		exit $OCF_ERR_CONFIGURED;
	fi

	if ! ocf_is_decimal "$OCF_RESKEY_multiplier"; then
		ocf_exit_reason "Invalid OCF_RESKEY_multiplier [$OCF_RESKEY_multiplier]"
		exit $OCF_ERR_CONFIGURED
	fi

	ATTRNAME=${OCF_RESKEY_name:-"ovsmonitor-$BOND"}

	REP_COUNT=${OCF_RESKEY_repeat_count}
	if ! ocf_is_decimal "$REP_COUNT" -o [ $REP_COUNT -lt 1 ]; then
		ocf_exit_reason "Invalid OCF_RESKEY_repeat_count [$REP_COUNT]"
		exit $OCF_ERR_CONFIGURED
	fi
	REP_INTERVAL_S=${OCF_RESKEY_repeat_interval}
	if ! ocf_is_decimal "$REP_INTERVAL_S"; then
		ocf_exit_reason "Invalid OCF_RESKEY_repeat_interval [$REP_INTERVAL_S]"
		exit $OCF_ERR_CONFIGURED
	fi
	if ! ocf_is_decimal "$OCF_RESKEY_pktcnt_timeout"; then
		ocf_exit_reason "Invalid OCF_RESKEY_pktcnt_timeout [$OCF_RESKEY_pktcnt_timeout]"
		exit $OCF_ERR_CONFIGURED
	fi
	return $OCF_SUCCESS
}

# get the link status on $BOND
# asks ip about running (up) bonds, returns the number of matching bond names that are up
get_link_status () {
	#$IP2UTIL -o link show up dev "$BOND" | grep -v 'NO-CARRIER' | grep -c "$BOND"
	ovs-appctl bond/show "$BOND"|awk -F: '/^slave/ {print $2}'|grep -c enabled
}

# returns the number of received rx packets on $BOND
get_rx_packets () {
	ocf_log debug "bond $BOND - bridge $BRIDGE"
	#$IP2UTIL -o -s link show dev "$BOND" \
	#	| sed 's/.* RX: [^0-9]*[0-9]* *\([0-9]*\) .*/\1/'
	local ovs_port

	for ovs_port in $(ovs-appctl bond/show $BOND|awk '/^slave/ {gsub(":","");print $2}') ; do
		ovs-ofctl dump-ports $BRIDGE $ovs_port
	done \
		| awk -F, 'BEGIN{total=0} /rx/ {gsub(".*pkts=","");total=total+int($1)} END{print total}'
}

# watch for packet counter changes for max. OCF_RESKEY_pktcnt_timeout seconds
# returns immedeately with return code 0 if any packets were received
# otherwise 1 is returned
watch_pkt_counter () {
	local RX_PACKETS_NEW
	local RX_PACKETS_OLD
	RX_PACKETS_OLD="`get_rx_packets`"
	for n in `seq $(( $OCF_RESKEY_pktcnt_timeout * 10 ))`; do
		sleep 0.1
		RX_PACKETS_NEW="`get_rx_packets`"
		ocf_log debug "RX_PACKETS_OLD: $RX_PACKETS_OLD	RX_PACKETS_NEW: $RX_PACKETS_NEW"
		if [ "$RX_PACKETS_OLD" -ne "$RX_PACKETS_NEW" ]; then
			ocf_log debug "we received some packets."
			return 0
		fi
	done
	return 1
}

#
# Check the bond depending on the level given as parameter: $OCF_RESKEY_check_level
#
# 10: watch for packet counter changes
#
#
# 30:  watch for packet counter changes in promiscios mode
#
# If unsuccessfull in levels 18 and above,
# the tests for higher check levels are run.
#
if_check () {
	# always check link status first
	link_status="`get_link_status`"
	ocf_log debug "link_status: $link_status (up > 0, down = 0)"

	if [ $link_status -eq 0 ]; then
		ocf_log notice "link_status: DOWN"
		return $OCF_NOT_RUNNING
	fi

	# if using link_status_only, skip RX count related test
	if ocf_is_true "$OCF_RESKEY_link_status_only"; then
		return $OCF_SUCCESS
	fi

	# watch for packet counter changes
	ocf_log debug "watch for packet counter changes"
	watch_pkt_counter
	if [ $? -eq 0 ]; then
		return $OCF_SUCCESS
	else
		ocf_log debug "No packets received during packet watch timeout"
	fi

	# watch for packet counter changes in promiscios mode
#	ocf_log debug "watch for packet counter changes in promiscios mode"
	# be sure switch off promiscios mode in any case
	# TODO: check first, wether promisc is already on and leave it untouched.
#	trap "$IP2UTIL link set dev $BOND promisc off; exit" INT TERM EXIT
#		$IP2UTIL link set dev $BOND promisc on
#		watch_pkt_counter && return $OCF_SUCCESS
#		$IP2UTIL link set dev $BOND promisc off
#	trap - INT TERM EXIT

	# looks like it's not working (for whatever reason)
	return $OCF_NOT_RUNNING
}

#######################################################################

if_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
}

set_cib_value() {
	local score=`expr $1 \* $OCF_RESKEY_multiplier`
	attrd_updater -n $ATTRNAME -v $score
	local rc=$?
	case $rc in
		0) ocf_log debug "attrd_updater: Updated $ATTRNAME = $score" ;;
		*) ocf_log warn "attrd_updater: Could not update $ATTRNAME = $score: rc=$rc";;
	esac
	return $rc
}

if_monitor() {
	ha_pseudo_resource $OCF_RESOURCE_INSTANCE monitor
	local pseudo_status=$?
	if [ $pseudo_status -ne $OCF_SUCCESS ]; then
		exit $pseudo_status
	fi

	local mon_rc=$OCF_NOT_RUNNING
	local attr_rc=$OCF_NOT_RUNNING
	local runs=0
	local start_time
	local end_time
	local sleep_time
	while [ $mon_rc -ne $OCF_SUCCESS -a $REP_COUNT -gt 0 ]
	do
		start_time=`date +%s%N`
		if_check
		mon_rc=$?
		REP_COUNT=$(( $REP_COUNT - 1 ))
		if [ $mon_rc -ne $OCF_SUCCESS -a $REP_COUNT -gt 0 ]; then
			ocf_log warn "Monitoring of $OCF_RESOURCE_INSTANCE failed, $REP_COUNT retries left."
			end_time=`date +%s%N`
			sleep_time=`echo "scale=9; ( $start_time + ( $REP_INTERVAL_S * 1000000000 ) - $end_time ) / 1000000000" | bc -q 2> /dev/null`
			sleep $sleep_time 2> /dev/null
			runs=$(($runs + 1))
		fi

		if [ $mon_rc -eq $OCF_SUCCESS -a $runs -ne 0 ]; then
			ocf_log info "Monitoring of $OCF_RESOURCE_INSTANCE recovered from error"
		fi
	done

	ocf_log debug "Monitoring return code: $mon_rc"
	if [ $mon_rc -eq $OCF_SUCCESS ]; then
		set_cib_value 1
		attr_rc=$?
	else
		ocf_log err "Monitoring of $OCF_RESOURCE_INSTANCE failed."
		set_cib_value 0
		attr_rc=$?
	fi

	## The resource should not fail, if the bond is down. It should fail, if the update of the CIB variable has errors.
	## To react on the bond failure you must use constraints based on the CIB variable value, not on the resource itself.
	exit $attr_rc
}

if_stop()
{
	attrd_updater -D -n $ATTRNAME
	ha_pseudo_resource $OCF_RESOURCE_INSTANCE stop
}

if_start()
{
	local rc
	ha_pseudo_resource $OCF_RESOURCE_INSTANCE start
	rc=$?
	if [ $rc -ne $OCF_SUCCESS ]; then
		ocf_exit_reason "Failure to create ovsmonitor state file"
		return $rc
	fi

	# perform the first monitor during the start operation
	if_monitor
	return $?
}


if_validate() {
	check_binary ovs-vsctl
	check_binary ovs-appctl
	check_binary ovs-ofctl
	check_binary bc
	if_init
}

case $__OCF_ACTION in
meta-data)	meta_data
		;;
usage|help)	if_usage
		exit $OCF_SUCCESS
		;;
esac

if_validate

case $__OCF_ACTION in
start)		if_start
		exit $?
		;;
stop)		if_stop
		exit $?
		;;
monitor|status)	if_monitor
		exit $?
		;;
validate-all)	exit $?
		;;
*)		if_usage
		exit $OCF_ERR_UNIMPLEMENTED
		;;
esac