path: root/heartbeat/IPaddr2

#!/bin/sh
#
#	$Id: IPaddr2.in,v 1.24 2006/08/09 13:01:54 lars Exp $
#
#       OCF Resource Agent compliant IPaddr2 script.
#
# 	Based on work by Tuomo Soini, ported to the OCF RA API by Lars
# 	Marowsky-Brée. Implements Cluster Alias IP functionality too.
#
#	Cluster Alias IP cleanup, fixes and testing by Michael Schwartzkopff
#
#
# Copyright (c) 2003 Tuomo Soini
# Copyright (c) 2004-2006 SUSE LINUX AG, Lars Marowsky-Brée
#                    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.
#
#


# TODO: 
# - There ought to be an ocf_run_cmd function which does all logging,
#   timeout handling etc for us
# - Make this the standard IP address agent on Linux; the other
#   platforms simply should ignore the additional parameters OR can use
#   the legacy heartbeat resource script...
# - Check LVS <-> clusterip incompatibilities.
#
#	OCF parameters are as below
#	OCF_RESKEY_ip
#	OCF_RESKEY_broadcast
#	OCF_RESKEY_nic
#	OCF_RESKEY_cidr_netmask
#	OCF_RESKEY_iflabel
#	OCF_RESKEY_mac
#	OCF_RESKEY_clusterip_hash
#	OCF_RESKEY_arp_interval
#	OCF_RESKEY_arp_count
#	OCF_RESKEY_arp_bg
#	OCF_RESKEY_preferred_lft
#
#	OCF_RESKEY_CRM_meta_clone
#	OCF_RESKEY_CRM_meta_clone_max


#######################################################################
# Initialization:

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

# Defaults
OCF_RESKEY_ip_default=""
OCF_RESKEY_cidr_netmask_default=""
OCF_RESKEY_broadcast_default=""
OCF_RESKEY_iflabel_default=""
OCF_RESKEY_cidr_netmask_default=""
OCF_RESKEY_lvs_support_default=false
OCF_RESKEY_lvs_ipv6_addrlabel_default=false
OCF_RESKEY_lvs_ipv6_addrlabel_value_default=99
OCF_RESKEY_clusterip_hash_default="sourceip-sourceport"
OCF_RESKEY_mac_default=""
OCF_RESKEY_unique_clone_address_default=false
OCF_RESKEY_arp_interval_default=200
OCF_RESKEY_arp_count_default=5
OCF_RESKEY_arp_count_refresh_default=0
OCF_RESKEY_arp_bg_default=""
OCF_RESKEY_arp_sender_default=""
OCF_RESKEY_send_arp_opts_default=""
OCF_RESKEY_flush_routes_default="false"
OCF_RESKEY_run_arping_default=false
OCF_RESKEY_nodad_default=false
OCF_RESKEY_noprefixroute_default="false"
OCF_RESKEY_preferred_lft_default="forever"
OCF_RESKEY_network_namespace_default=""

: ${OCF_RESKEY_ip=${OCF_RESKEY_ip_default}}
: ${OCF_RESKEY_cidr_netmask=${OCF_RESKEY_cidr_netmask_default}}
: ${OCF_RESKEY_broadcast=${OCF_RESKEY_broadcast_default}}
: ${OCF_RESKEY_iflabel=${OCF_RESKEY_iflabel_default}}
: ${OCF_RESKEY_lvs_support=${OCF_RESKEY_lvs_support_default}}
: ${OCF_RESKEY_lvs_ipv6_addrlabel=${OCF_RESKEY_lvs_ipv6_addrlabel_default}}
: ${OCF_RESKEY_lvs_ipv6_addrlabel_value=${OCF_RESKEY_lvs_ipv6_addrlabel_value_default}}
: ${OCF_RESKEY_clusterip_hash=${OCF_RESKEY_clusterip_hash_default}}
: ${OCF_RESKEY_mac=${OCF_RESKEY_mac_default}}
: ${OCF_RESKEY_unique_clone_address=${OCF_RESKEY_unique_clone_address_default}}
: ${OCF_RESKEY_arp_interval=${OCF_RESKEY_arp_interval_default}}
: ${OCF_RESKEY_arp_count=${OCF_RESKEY_arp_count_default}}
: ${OCF_RESKEY_arp_count_refresh=${OCF_RESKEY_arp_count_refresh_default}}
: ${OCF_RESKEY_arp_bg=${OCF_RESKEY_arp_bg_default}}
: ${OCF_RESKEY_arp_sender=${OCF_RESKEY_arp_sender_default}}
: ${OCF_RESKEY_send_arp_opts=${OCF_RESKEY_send_arp_opts_default}}
: ${OCF_RESKEY_flush_routes=${OCF_RESKEY_flush_routes_default}}
: ${OCF_RESKEY_run_arping=${OCF_RESKEY_run_arping_default}}
: ${OCF_RESKEY_nodad=${OCF_RESKEY_nodad_default}}
: ${OCF_RESKEY_noprefixroute=${OCF_RESKEY_noprefixroute_default}}
: ${OCF_RESKEY_preferred_lft=${OCF_RESKEY_preferred_lft_default}}
: ${OCF_RESKEY_network_namespace=${OCF_RESKEY_network_namespace_default}}

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

SENDARP=$HA_BIN/send_arp
SENDUA=$HA_BIN/send_ua
FINDIF=findif
VLDIR=$HA_RSCTMP
SENDARPPIDDIR=$HA_RSCTMP
CIP_lockfile=$HA_RSCTMP/IPaddr2-CIP-${OCF_RESKEY_ip}

IPADDR2_CIP_IPTABLES=$IPTABLES

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

meta_data() {
	cat <<END
<?xml version="1.0"?>
<!DOCTYPE resource-agent SYSTEM "ra-api-1.dtd">
<resource-agent name="IPaddr2" version="1.0">
<version>1.0</version>

<longdesc lang="en">
This Linux-specific resource manages IP alias IP addresses.
It can add an IP alias, or remove one.
In addition, it can implement Cluster Alias IP functionality
if invoked as a clone resource.

If used as a clone, "shared address with a trivial, stateless
(autonomous) load-balancing/mutual exclusion on ingress" mode gets
applied (as opposed to "assume resource uniqueness" mode otherwise).
For that, Linux firewall (kernel and userspace) is assumed, and since
recent distributions are ambivalent in plain "iptables" command to
particular back-end resolution, "iptables-legacy" (when present) gets
prioritized so as to avoid incompatibilities (note that respective
ipt_CLUSTERIP firewall extension in use here is, at the same time,
marked deprecated, yet said "legacy" layer can make it workable,
literally, to this day) with "netfilter" one (as in "iptables-nft").
In that case, you should explicitly set clone-node-max &gt;= 2,
and/or clone-max &lt; number of nodes. In case of node failure,
clone instances need to be re-allocated on surviving nodes.
This would not be possible if there is already an instance
on those nodes, and clone-node-max=1 (which is the default).

When the specified IP address gets assigned to a respective interface, the
resource agent sends unsolicited ARP (Address Resolution Protocol, IPv4) or NA
(Neighbor Advertisement, IPv6) packets to inform neighboring machines about the
change. This functionality is controlled for both IPv4 and IPv6 by shared
'arp_*' parameters.
</longdesc>

<shortdesc lang="en">Manages virtual IPv4 and IPv6 addresses (Linux specific version)</shortdesc>

<parameters>
<parameter name="ip" unique="1" required="1">
<longdesc lang="en">
The IPv4 (dotted quad notation) or IPv6 address (colon hexadecimal notation)
example IPv4 "192.168.1.1".
example IPv6 "2001:db8:DC28:0:0:FC57:D4C8:1FFF".
</longdesc>
<shortdesc lang="en">IPv4 or IPv6 address</shortdesc>
<content type="string" default="${OCF_RESKEY_ip_default}" />
</parameter>
<parameter name="nic" unique="0">
<longdesc lang="en">
The base network interface on which the IP address will be brought
online. 
If left empty, the script will try and determine this from the
routing table.

Do NOT specify an alias interface in the form eth0:1 or anything here;
rather, specify the base interface only.
If you want a label, see the iflabel parameter.

Prerequisite:

There must be at least one static IP address, which is not managed by
the cluster, assigned to the network interface.
If you can not assign any static IP address on the interface,
modify this kernel parameter:

sysctl -w net.ipv4.conf.all.promote_secondaries=1 # (or per device)
</longdesc>
<shortdesc lang="en">Network interface</shortdesc>
<content type="string"/>
</parameter>

<parameter name="cidr_netmask">
<longdesc lang="en">
The netmask for the interface in CIDR format
(e.g., 24 and not 255.255.255.0)

If unspecified, the script will also try to determine this from the
routing table.
</longdesc>
<shortdesc lang="en">CIDR netmask</shortdesc>
<content type="string" default="${OCF_RESKEY_cidr_netmask_default}"/>
</parameter>

<parameter name="broadcast">
<longdesc lang="en">
Broadcast address associated with the IP. It is possible to use the
special symbols '+' and '-' instead of the broadcast address. In this
case, the broadcast address is derived by setting/resetting the host
bits of the interface prefix.
</longdesc>
<shortdesc lang="en">Broadcast address</shortdesc>
<content type="string" default="${OCF_RESKEY_broadcast_default}"/>
</parameter>

<parameter name="iflabel">
<longdesc lang="en">
You can specify an additional label for your IP address here.
This label is appended to your interface name.

The kernel allows alphanumeric labels up to a maximum length of 15
characters including the interface name and colon (e.g. eth0:foobar1234)

A label can be specified in nic parameter but it is deprecated.
If a label is specified in nic name, this parameter has no effect.
</longdesc>
<shortdesc lang="en">Interface label</shortdesc>
<content type="string" default="${OCF_RESKEY_iflabel_default}"/>
</parameter>

<parameter name="lvs_support">
<longdesc lang="en">
Enable support for LVS Direct Routing configurations. In case a IP
address is stopped, only move it to the loopback device to allow the
local node to continue to service requests, but no longer advertise it
on the network.

Notes for IPv6:
It is not necessary to enable this option on IPv6.
Instead, enable 'lvs_ipv6_addrlabel' option for LVS-DR usage on IPv6.
</longdesc>
<shortdesc lang="en">Enable support for LVS DR</shortdesc>
<content type="boolean" default="${OCF_RESKEY_lvs_support_default}"/>
</parameter>

<parameter name="lvs_ipv6_addrlabel">
<longdesc lang="en">
Enable adding IPv6 address label so IPv6 traffic originating from
the address's interface does not use this address as the source.
This is necessary for LVS-DR health checks to realservers to work. Without it,
the most recently added IPv6 address (probably the address added by IPaddr2)
will be used as the source address for IPv6 traffic from that interface and
since that address exists on loopback on the realservers, the realserver
response to pings/connections will never leave its loopback.
See RFC3484 for the detail of the source address selection.

See also 'lvs_ipv6_addrlabel_value' parameter.
</longdesc>
<shortdesc lang="en">Enable adding IPv6 address label.</shortdesc>
<content type="boolean" default="${OCF_RESKEY_lvs_ipv6_addrlabel_default}"/>
</parameter>

<parameter name="lvs_ipv6_addrlabel_value">
<longdesc lang="en">
Specify IPv6 address label value used when 'lvs_ipv6_addrlabel' is enabled.
The value should be an unused label in the policy table
which is shown by 'ip addrlabel list' command.
You would rarely need to change this parameter.
</longdesc>
<shortdesc lang="en">IPv6 address label value.</shortdesc>
<content type="integer" default="${OCF_RESKEY_lvs_ipv6_addrlabel_value_default}"/>
</parameter>

<parameter name="mac">
<longdesc lang="en">
Set the interface MAC address explicitly. Currently only used in case of
the Cluster IP Alias. Leave empty to chose automatically.

</longdesc>
<shortdesc lang="en">Cluster IP MAC address</shortdesc>
<content type="string" default="${OCF_RESKEY_mac_default}"/>
</parameter>

<parameter name="clusterip_hash">
<longdesc lang="en">
Specify the hashing algorithm used for the Cluster IP functionality.

</longdesc>
<shortdesc lang="en">Cluster IP hashing function</shortdesc>
<content type="string" default="${OCF_RESKEY_clusterip_hash_default}"/>
</parameter>

<parameter name="unique_clone_address">
<longdesc lang="en">
If true, add the clone ID to the supplied value of IP to create
a unique address to manage 
</longdesc>
<shortdesc lang="en">Create a unique address for cloned instances</shortdesc>
<content type="boolean" default="${OCF_RESKEY_unique_clone_address_default}"/>
</parameter>

<parameter name="arp_interval">
<longdesc lang="en">
Specify the interval between unsolicited ARP (IPv4) or NA (IPv6) packets in
milliseconds.

This parameter is deprecated and used for the backward compatibility only.
It is effective only for the send_arp binary which is built with libnet,
and send_ua for IPv6. It has no effect for other arp_sender.
</longdesc>
<shortdesc lang="en">ARP/NA packet interval in ms (deprecated)</shortdesc>
<content type="integer" default="${OCF_RESKEY_arp_interval_default}"/>
</parameter>

<parameter name="arp_count">
<longdesc lang="en">
Number of unsolicited ARP (IPv4) or NA (IPv6) packets to send at resource
initialization.
</longdesc>
<shortdesc lang="en">ARP/NA packet count sent during initialization</shortdesc>
<content type="integer" default="${OCF_RESKEY_arp_count_default}"/>
</parameter>

<parameter name="arp_count_refresh">
<longdesc lang="en">
For IPv4, number of unsolicited ARP packets to send during resource monitoring.
Doing so helps mitigate issues of stuck ARP caches resulting from split-brain
situations.
</longdesc>
<shortdesc lang="en">ARP packet count sent during monitoring</shortdesc>
<content type="integer" default="${OCF_RESKEY_arp_count_refresh_default}"/>
</parameter>

<parameter name="arp_bg">
<longdesc lang="en">
Whether or not to send the ARP (IPv4) or NA (IPv6) packets in the background.
The default is true for IPv4 and false for IPv6.
</longdesc>
<shortdesc lang="en">ARP/NA from background</shortdesc>
<content type="string" default="${OCF_RESKEY_arp_bg_default}"/>
</parameter>

<parameter name="arp_sender">
<longdesc lang="en">
For IPv4, the program to send ARP packets with on start. Available options are:
 - send_arp: default
 - ipoibarping: default for infiniband interfaces if ipoibarping is available
 - iputils_arping: use arping in iputils package
 - libnet_arping: use another variant of arping based on libnet
</longdesc>
<shortdesc lang="en">ARP sender</shortdesc>
<content type="string" default="${OCF_RESKEY_arp_sender_default}"/>
</parameter>

<parameter name="send_arp_opts">
<longdesc lang="en">
For IPv4, extra options to pass to the arp_sender program.
Available options are vary depending on which arp_sender is used.

A typical use case is specifying '-A' for iputils_arping to use
ARP REPLY instead of ARP REQUEST as Gratuitous ARPs.
</longdesc>
<shortdesc lang="en">Options for ARP sender</shortdesc>
<content type="string" default="${OCF_RESKEY_send_arp_opts_default}"/>
</parameter>

<parameter name="flush_routes">
<longdesc lang="en">
Flush the routing table on stop. This is for
applications which use the cluster IP address
and which run on the same physical host that the
IP address lives on. The Linux kernel may force that
application to take a shortcut to the local loopback
interface, instead of the interface the address
is really bound to. Under those circumstances, an
application may, somewhat unexpectedly, continue
to use connections for some time even after the
IP address is deconfigured. Set this parameter in
order to immediately disable said shortcut when the
IP address goes away.
</longdesc>
<shortdesc lang="en">Flush kernel routing table on stop</shortdesc>
<content type="boolean" default="${OCF_RESKEY_flush_routes_default}"/>
</parameter>

<parameter name="run_arping">
<longdesc lang="en">
For IPv4, whether or not to run arping for collision detection check.
</longdesc>
<shortdesc lang="en">Run arping for IPv4 collision detection check</shortdesc>
<content type="string" default="${OCF_RESKEY_run_arping_default}"/>
</parameter>

<parameter name="nodad">
<longdesc lang="en">
For IPv6, do not perform Duplicate Address Detection when adding the address.
</longdesc>
<shortdesc lang="en">Use nodad flag</shortdesc>
<content type="string" default="${OCF_RESKEY_nodad_default}"/>
</parameter>

<parameter name="noprefixroute">
<longdesc lang="en">
Use noprefixroute flag (see 'man ip-address').
</longdesc>
<shortdesc lang="en">Use noprefixroute flag</shortdesc>
<content type="string" default="${OCF_RESKEY_noprefixroute_default}"/>
</parameter>

<parameter name="preferred_lft">
<longdesc lang="en">
For IPv6, set the preferred lifetime of the IP address.
This can be used to ensure that the created IP address will not
be used as a source address for routing.
Expects a value as specified in section 5.5.4 of RFC 4862.
</longdesc>
<shortdesc lang="en">IPv6 preferred lifetime</shortdesc>
<content type="string" default="${OCF_RESKEY_preferred_lft_default}"/>
</parameter>

<parameter name="network_namespace">
<longdesc lang="en">
Specifies the network namespace to operate within.
The namespace must already exist, and the interface to be used must be within
the namespace.
</longdesc>
<shortdesc lang="en">Network namespace to use</shortdesc>
<content type="string" default="${OCF_RESKEY_network_namespace_default}"/>
</parameter>
</parameters>

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

	exit $OCF_SUCCESS
}

ip_init() {
	local rc

	if [ X`uname -s` != "XLinux" ]; then
		ocf_exit_reason "IPaddr2 only supported Linux."
		exit $OCF_ERR_INSTALLED
	fi

	if [ X"$OCF_RESKEY_ip" = "X" ] && [ "$__OCF_ACTION" != "stop" ]; then
		ocf_exit_reason "IP address (the ip parameter) is mandatory"
		exit $OCF_ERR_CONFIGURED
	fi

	if
          case $__OCF_ACTION in
            start|stop)		ocf_is_root;;
            *)			true;;
          esac
        then
          : YAY!
        else
		ocf_exit_reason "You must be root for $__OCF_ACTION operation."
		exit $OCF_ERR_PERM
	fi

	BASEIP="$OCF_RESKEY_ip"
	BRDCAST="$OCF_RESKEY_broadcast"
	NIC="$OCF_RESKEY_nic"
        # Note: We had a version out there for a while which used
        # netmask instead of cidr_netmask. Don't remove this aliasing code!
        if
          [ ! -z "$OCF_RESKEY_netmask" -a -z "$OCF_RESKEY_cidr_netmask" ]
        then
	  OCF_RESKEY_cidr_netmask=$OCF_RESKEY_netmask
	  export OCF_RESKEY_cidr_netmask
        fi
	NETMASK="$OCF_RESKEY_cidr_netmask"
	IFLABEL="$OCF_RESKEY_iflabel"
	IF_MAC="$OCF_RESKEY_mac"

	IP_INC_GLOBAL=${OCF_RESKEY_CRM_meta_clone_max:-1}
	IP_INC_NO=`expr ${OCF_RESKEY_CRM_meta_clone:-0} + 1`

	if ocf_is_true ${OCF_RESKEY_lvs_support} && [ $IP_INC_GLOBAL -gt 1 ]; then
		ocf_exit_reason "LVS and load sharing do not go together well"
		exit $OCF_ERR_CONFIGURED
	fi

	if ocf_is_decimal "$IP_INC_GLOBAL" && [ $IP_INC_GLOBAL -gt 0 ]; then
		:
	else
		ocf_exit_reason "Invalid meta-attribute clone_max [$IP_INC_GLOBAL], should be positive integer"
		exit $OCF_ERR_CONFIGURED
	fi

	echo $OCF_RESKEY_ip | grep -qs ":"
	if [ $? -ne 0 ];then
		FAMILY=inet
		if ocf_is_true $OCF_RESKEY_lvs_ipv6_addrlabel ;then
			ocf_exit_reason "IPv4 does not support lvs_ipv6_addrlabel"
			exit $OCF_ERR_CONFIGURED
		fi
		if [ -z "$OCF_RESKEY_arp_bg" ]; then
			OCF_RESKEY_arp_bg=true
		fi
	else
		FAMILY=inet6
		# address sanitization defined in RFC5952
		SANITIZED_IP=$($IP2UTIL route get $OCF_RESKEY_ip 2> /dev/null | awk '$1~/:/ {print $1}  $2~/:/ {print $2}')
                if [ -n "$SANITIZED_IP" ]; then
                    OCF_RESKEY_ip="$SANITIZED_IP"
                fi

		if ocf_is_true $OCF_RESKEY_lvs_support ;then
			ocf_exit_reason "The IPv6 does not support lvs_support"
			exit $OCF_ERR_CONFIGURED
		fi
		if ocf_is_true $OCF_RESKEY_lvs_ipv6_addrlabel ;then
			if ocf_is_decimal "$OCF_RESKEY_lvs_ipv6_addrlabel_value" && [ $OCF_RESKEY_lvs_ipv6_addrlabel_value -ge 0 ]; then
			    :
			else
			    ocf_exit_reason "Invalid lvs_ipv6_addrlabel_value [$OCF_RESKEY_lvs_ipv6_addrlabel_value], should be positive integer"
			    exit $OCF_ERR_CONFIGURED
			fi
		fi
		if [ -z "$OCF_RESKEY_arp_bg" ]; then
			OCF_RESKEY_arp_bg=false
		fi
	fi

	# support nic:iflabel format in nic parameter
	case $NIC in
	    *:*)
		IFLABEL=`echo $NIC | sed 's/[^:]*://'`
		NIC=`echo $NIC | sed 's/:.*//'`
		# only the base name should be passed to findif
		OCF_RESKEY_nic=$NIC
		;;
	esac

	# $FINDIF takes its parameters from the environment
	#
	NICINFO=`$FINDIF`
	rc=$?
	if
	  [ $rc -eq 0 ]
        then
	    NICINFO=`echo "$NICINFO" | sed -e 's/netmask\ //;s/broadcast\ //'`
	    NIC=`echo "$NICINFO" | cut -d" " -f1`
	    NETMASK=`echo "$NICINFO" | cut -d" " -f2`
	    BRDCAST=`echo "$NICINFO" | cut -d" " -f3`
	else
		# findif couldn't find the interface
		if ocf_is_probe; then
			ocf_log info "[$FINDIF] failed"
			exit $OCF_NOT_RUNNING
		elif [ "$__OCF_ACTION" = stop ]; then
			ocf_log warn "[$FINDIF] failed"
			exit $OCF_SUCCESS
		else
			ocf_exit_reason "[$FINDIF] failed"
			exit $rc
		fi
	fi
	
	SENDARPPIDFILE="$SENDARPPIDDIR/send_arp-$OCF_RESKEY_ip"

	if [ -n "$IFLABEL" ]; then
		IFLABEL=${NIC}:${IFLABEL}
		if [ ${#IFLABEL} -gt 15 ]; then
			ocf_exit_reason "Interface label [$IFLABEL] exceeds maximum character limit of 15"
			exit $OCF_ERR_CONFIGURED
		fi
	fi

	if [ "$IP_INC_GLOBAL" -gt 1 ] && ! ocf_is_true "$OCF_RESKEY_unique_clone_address"; then
		IP_CIP="yes"
		IP_CIP_HASH="${OCF_RESKEY_clusterip_hash}"
		if [ -z "$IF_MAC" ]; then
			# Choose a MAC
			# 1. Concatenate some input together
			# 2. This doesn't need to be a cryptographically
			#    secure hash.
			# 3. Drop everything after the first 6 octets (12 chars)
			# 4. Delimit the octets with ':'
			# 5. Make sure the first octet is odd,
			#    so the result is a multicast MAC
			IF_MAC=`echo $OCF_RESKEY_ip $NETMASK $BRDCAST |	\
				md5sum |				\
				sed -e 's#\(............\).*#\1#'	\
				    -e 's#..#&:#g; s#:$##'		\
				    -e 's#^\(.\)[02468aAcCeE]#\11#'`
		fi
		IP_CIP_FILE="/proc/net/ipt_CLUSTERIP/$OCF_RESKEY_ip"
	fi
}

#
#	Find out which interfaces serve the given IP address and netmask.
#	The arguments are an IP address and a netmask.
#	Its output are interface names devided by spaces (e.g., "eth0 eth1").
#
find_interface() {
	local ipaddr="$1"
	local netmask="$2"

	#
	# List interfaces but exclude FreeS/WAN ipsecN virtual interfaces
	#
	local iface="`$IP2UTIL -o -f $FAMILY addr show \
		| grep " $ipaddr/$netmask" \
		| cut -d ' ' -f2 \
		| grep -v '^ipsec[0-9][0-9]*$'`"

	echo "$iface"
	return 0
}

#
#        Delete an interface
#
delete_interface () {
	ipaddr="$1"
	iface="$2"
	netmask="$3"

	CMD="$IP2UTIL -f $FAMILY addr delete $ipaddr/$netmask dev $iface"

	ocf_run $CMD || return $OCF_ERR_GENERIC

	if ocf_is_true $OCF_RESKEY_flush_routes; then
	    ocf_run $IP2UTIL route flush cache
	fi

	if [ "$FAMILY" = "inet6" ] && ocf_is_true $OCF_RESKEY_lvs_ipv6_addrlabel ;then
	    delete_ipv6_addrlabel $ipaddr
	fi

	return $OCF_SUCCESS
}

#
#        Add an interface
#
add_interface () {
	local cmd msg extra_opts ipaddr netmask broadcast iface label

	ipaddr="$1"
	netmask="$2"
	broadcast="$3"
	iface="$4"
	label="$5"

	if [ "$FAMILY" = "inet" ] && ocf_is_true $OCF_RESKEY_run_arping &&
	   check_binary arping; then
		arping -q -c 2 -w 3 -D -I $iface $ipaddr
		if [ $? = 1 ]; then
			ocf_log err "IPv4 address collision $ipaddr [DAD]"
			return $OCF_ERR_GENERIC
		fi
	fi

	if [ "$FAMILY" = "inet6" ] && ocf_is_true $OCF_RESKEY_lvs_ipv6_addrlabel ;then
	    add_ipv6_addrlabel $ipaddr
	fi

	cmd="$IP2UTIL -f $FAMILY addr add $ipaddr/$netmask dev $iface"
	msg="Adding $FAMILY address $ipaddr/$netmask to device $iface"
	if [ "$broadcast" != "none" ]; then
		cmd="$IP2UTIL -f $FAMILY addr add $ipaddr/$netmask brd $broadcast dev $iface"
		msg="Adding $FAMILY address $ipaddr/$netmask with broadcast address $broadcast to device $iface"
	fi

	extra_opts=""
	if [ "$FAMILY" = "inet6" ] && ocf_is_true "${OCF_RESKEY_nodad}"; then
		extra_opts="$extra_opts nodad"
	fi

	if ocf_is_true "${OCF_RESKEY_noprefixroute}"; then
		extra_opts="$extra_opts noprefixroute"
	fi

	if [ ! -z "$label" ]; then
		extra_opts="$extra_opts label $label"
	fi
	if [ "$FAMILY" = "inet6" ] ;then
		extra_opts="$extra_opts preferred_lft $OCF_RESKEY_preferred_lft"
	fi
	if [ -n "$extra_opts" ]; then
		cmd="$cmd$extra_opts"
		msg="$msg (with$extra_opts)"
	fi

	ocf_log info "$msg"
	ocf_run $cmd || return $OCF_ERR_GENERIC

	msg="Bringing device $iface up"
	cmd="$IP2UTIL link set $iface up"
	ocf_log info "$msg"
	ocf_run $cmd || return $OCF_ERR_GENERIC

	return $OCF_SUCCESS
}

#
#        Delete a route
#
delete_route () {
	prefix="$1"
	iface="$2"

	CMD="$IP2UTIL route delete $prefix dev $iface"

	ocf_log info "$CMD"
	$CMD

	return $?
}

#      On Linux systems the (hidden) loopback interface may
#      conflict with the requested IP address. If so, this
#      unoriginal code will remove the offending loopback address
#      and save it in VLDIR so it can be added back in later
#      when the IPaddr is released.
#
#      TODO: This is very ugly and should be controlled by an additional
#      instance parameter. Or even: multi-state, with the IP only being
#      "active" on the master!?
#
remove_conflicting_loopback() {
	ipaddr="$1"
	netmask="$2"
	broadcast="$3"
	ifname="$4"

	ocf_log info "Removing conflicting loopback $ifname."
	if
		echo "$ipaddr $netmask $broadcast $ifname" > "$VLDIR/$ipaddr"
	then
		: Saved loopback information in $VLDIR/$ipaddr
	else
		ocf_log err "Could not save conflicting loopback $ifname." \
		       "it will not be restored."
	fi
	delete_interface "$ipaddr" "$ifname" "$netmask"
	# Forcibly remove the route (if it exists) to the loopback.
	delete_route "$ipaddr" "$ifname"
}

#
#	On Linux systems the (hidden) loopback interface may
#	need to be restored if it has been taken down previously
#	by remove_conflicting_loopback()
#
restore_loopback() {
	ipaddr="$1"

	if [ -s "$VLDIR/$ipaddr" ]; then
		ifinfo=`cat "$VLDIR/$ipaddr"`
		ocf_log info "Restoring loopback IP Address " \
		    "$ifinfo."
		add_interface $ifinfo
		rm -f "$VLDIR/$ipaddr"
	fi
}

add_ipv6_addrlabel() {
	local cmd ipaddr value
	ipaddr="$1"
	value="$OCF_RESKEY_lvs_ipv6_addrlabel_value"

	cmd="$IP2UTIL addrlabel add prefix $ipaddr label $value"
	ocf_log info "Adding IPv6 address label prefix $ipaddr label $value"
	ocf_run $cmd || ocf_log warn "$cmd failed."
}

delete_ipv6_addrlabel() {
	local cmd ipaddr value
	ipaddr="$1"
	value="$OCF_RESKEY_lvs_ipv6_addrlabel_value"

	cmd="$IP2UTIL addrlabel del prefix $ipaddr label $value"
	ocf_run $cmd # an error can be ignored
}

is_infiniband() {
	$IP2UTIL link show $NIC | grep link/infiniband >/dev/null
}

log_arp_sender() {
    local cmdline
    local output
    local rc
    cmdline="$@"

    output=$($cmdline 2>&1)
    rc=$?
    if [ $rc -ne 0 ] && \
       [ "$ARP_SENDER" != "libnet_arping" ] ; then
        # libnet_arping always return an error as no answers
        ocf_log err "Could not send gratuitous arps: rc=$rc"
    fi
    ocf_log $LOGLEVEL "$output"
}

# wrapper function to manage PID file to run arping in background
run_with_pidfile() {
    local cmdline
    local pid
    local rc

    cmdline="$@"

    $cmdline &
    pid=$!
    echo "$pid" > $SENDARPPIDFILE
    wait $pid
    rc=$?
    rm -f $SENDARPPIDFILE
    return $rc
}

build_arp_sender_cmd() {
    case "$ARP_SENDER" in
	send_arp)
	    if [ "x$IP_CIP" = "xyes" ] ; then
	        if [ x = "x$IF_MAC" ] ; then
		    MY_MAC=auto
	        else
		    # send_arp.linux should return without doing anything in this case
		    MY_MAC=`echo ${IF_MAC} | sed -e 's/://g'`
	        fi
	    else
		    MY_MAC=auto
	    fi

	    ARGS="$OCF_RESKEY_send_arp_opts -i $OCF_RESKEY_arp_interval -r $ARP_COUNT -p $SENDARPPIDFILE $NIC $OCF_RESKEY_ip $MY_MAC not_used not_used"
	    ARP_SENDER_CMD="$SENDARP $ARGS"
	    ;;
	iputils_arping)
	    ARGS="$OCF_RESKEY_send_arp_opts -U -c $ARP_COUNT -I $NIC $OCF_RESKEY_ip"
	    ARP_SENDER_CMD="run_with_pidfile arping $ARGS"
	    ;;
	libnet_arping)
	    ARGS="$OCF_RESKEY_send_arp_opts -U -c $ARP_COUNT -i $NIC -S $OCF_RESKEY_ip $OCF_RESKEY_ip"
	    ARP_SENDER_CMD="run_with_pidfile arping $ARGS"
	    ;;
	ipoibarping)
	    ARGS="-q -c $ARP_COUNT -U -I $NIC $OCF_RESKEY_ip"
	    ARP_SENDER_CMD="ipoibarping $ARGS"
	    ;;
	*)
	    # should not occur
	    ocf_exit_reason "unrecognized arp_sender value: $ARP_SENDER"
	    exit $OCF_ERR_GENERIC
	    ;;
    esac
}

#
# Send Unsolicited ARPs to update neighbor's ARP cache
#
run_arp_sender() {
	if [ "x$1" = "xrefresh" ] ; then
		ARP_COUNT=$OCF_RESKEY_arp_count_refresh
		LOGLEVEL=debug
	else
		ARP_COUNT=$OCF_RESKEY_arp_count
		LOGLEVEL=info
	fi
	if [ $ARP_COUNT -eq 0 ] ; then
		return
	fi

	# do not need to send Gratuitous ARPs in the Cluster IP configuration
	# except send_arp.libnet binary to retain the old behavior
	if [ "x$IP_CIP" = "xyes" ] && \
	   [ "x$ARP_SENDER" != "xsend_arp" ] ; then
		ocf_log info "Gratuitous ARPs are not sent in the Cluster IP configuration"
		return
	fi

        # prepare arguments for each arp sender program
        # $ARP_SENDER_CMD should be set
	build_arp_sender_cmd

	ocf_log $LOGLEVEL "$ARP_SENDER_CMD"

	if ocf_is_true $OCF_RESKEY_arp_bg; then
		log_arp_sender $ARP_SENDER_CMD &
	else
		log_arp_sender $ARP_SENDER_CMD
	fi
}

log_send_ua() {
	local cmdline
	local output
	local rc

	cmdline="$@"
	output=$($cmdline 2>&1)
	rc=$?
	if [ $rc -ne 0 ] ; then
		ocf_log err "Could not send ICMPv6 Unsolicited Neighbor Advertisements: rc=$rc"
	fi
	ocf_log info "$output"
	return $rc
}

#
# Run send_ua to note send ICMPv6 Unsolicited Neighbor Advertisements.
#
run_send_ua() {
	local i

	# Duplicate Address Detection [DAD]
	# Kernel will flag the IP as 'tentative' until it ensured that
	# there is no duplicates.
	# If there is, it will flag it as 'dadfailed'
	for i in $(seq 1 10); do
		ipstatus=$($IP2UTIL -o -f $FAMILY addr show dev $NIC to $OCF_RESKEY_ip/$NETMASK)
		case "$ipstatus" in
		*dadfailed*)
			ocf_log err "IPv6 address collision $OCF_RESKEY_ip [DAD]"
			$IP2UTIL -f $FAMILY addr del dev $NIC $OCF_RESKEY_ip/$NETMASK
			if [ $? -ne 0 ]; then
				ocf_log err "Could not delete IPv6 address"
			fi
			return $OCF_ERR_GENERIC
			;;
		*tentative*)
			if [ $i -eq 10 ]; then
				ocf_log warn "IPv6 address : DAD is still in tentative"
			fi
			;;
		*)
			break
			;;
		esac
		sleep 1
	done
	# Now the address should be usable

	ARGS="-i $OCF_RESKEY_arp_interval -c $OCF_RESKEY_arp_count $OCF_RESKEY_ip $NETMASK $NIC"
	ocf_log info "$SENDUA $ARGS"
	if ocf_is_true $OCF_RESKEY_arp_bg; then
		log_send_ua $SENDUA $ARGS &
	else
		log_send_ua $SENDUA $ARGS
	fi
}

# Do we already serve this IP address on the given $NIC?
#
# returns:
# ok = served (for CIP: + hash bucket)
# partial = served and no hash bucket (CIP only)
# partial2 = served and no CIP iptables rule
# no = nothing
#
ip_served() {
	if [ -z "$NIC" ]; then # no nic found or specified
		echo "no"
		return 0
	fi

	cur_nic="`find_interface $OCF_RESKEY_ip $NETMASK`"

	if [ -z "$cur_nic" ]; then
		echo "no"
		return 0
	fi

	if [ -z "$IP_CIP" ]; then
		for i in $cur_nic; do
			# only mark as served when on the same interfaces as $NIC
			[ "$i" = "$NIC" ] || continue
			echo "ok"
			return 0
		done
		# There used to be logic here to pretend "not served",
		# if ${OCF_RESKEY_lvs_support} was enabled, and the IP was
		# found active on "lo*" only.  With lvs_support on, you should
		# have NIC != lo, so thats already filtered
		# by the continue above.

		echo "no"
		return 0
	fi

	# Special handling for the CIP:
	if [ ! -e $IP_CIP_FILE ]; then
		echo "partial2"
		return 0
	fi
	if egrep -q "(^|,)${IP_INC_NO}(,|$)" $IP_CIP_FILE ; then
		echo "ok"
		return 0
	else
		echo "partial"
		return 0
	fi

	exit $OCF_ERR_GENERIC
}

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

ip_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
}

ip_start() {
	if [ -z "$NIC" ]; then
		ocf_exit_reason "No nic found or specified"
		exit $OCF_ERR_CONFIGURED
	fi

	if [ -n "$IP_CIP" ]; then
	    # Cluster IPs need special processing when the first bucket
	    #  is added to the node... take a lock to make sure only one
	    #  process executes that code
	    ocf_take_lock $CIP_lockfile
	    ocf_release_lock_on_exit $CIP_lockfile
	fi

	#
	#	Do we already service this IP address on $NIC?
	#
	local ip_status=`ip_served`

	if [ "$ip_status" = "ok" ]; then
		exit $OCF_SUCCESS
	fi
	
	if [ -n "$IP_CIP" ] && ([ $ip_status = "no" ] || [ $ip_status = "partial2" ]); then
		$MODPROBE ip_conntrack
		$IPADDR2_CIP_IPTABLES -I INPUT -d $OCF_RESKEY_ip -i $NIC -j CLUSTERIP \
				--new \
				--clustermac $IF_MAC \
				--total-nodes $IP_INC_GLOBAL \
				--local-node $IP_INC_NO \
				--hashmode $IP_CIP_HASH
		if [ $? -ne 0 ]; then
			ocf_exit_reason "iptables failed"
			exit $OCF_ERR_GENERIC
		fi
	fi

	if [ -n "$IP_CIP" ] && [ $ip_status = "partial" ]; then
		echo "+$IP_INC_NO" >$IP_CIP_FILE
	fi
	
	if [ "$ip_status" = "no" ]; then
		if ocf_is_true ${OCF_RESKEY_lvs_support}; then
			for i in `find_interface $OCF_RESKEY_ip 32`; do
				case $i in
				lo*)
					remove_conflicting_loopback $OCF_RESKEY_ip 32 255.255.255.255 lo
					;;
				esac
			done
		fi
		
		add_interface $OCF_RESKEY_ip $NETMASK ${BRDCAST:-none} $NIC $IFLABEL
		rc=$?

		if [ $rc -ne $OCF_SUCCESS ]; then
			ocf_exit_reason "Failed to add $OCF_RESKEY_ip"
			exit $rc
		fi
	fi

	case $NIC in
	lo*)
		: no need to run send_arp on loopback
		;;
	*)
		if [ $FAMILY = "inet" ];then
		    run_arp_sender
		else
		    if [ -x $SENDUA ]; then
			run_send_ua
			if [ $? -ne 0 ]; then
				ocf_exit_reason "run_send_ua failed."
				exit $OCF_ERR_GENERIC
			fi
		    fi
		fi
		;;
	esac
	exit $OCF_SUCCESS
}

ip_stop() {
	local ip_del_if="yes"
	if [ -n "$IP_CIP" ]; then
	    # Cluster IPs need special processing when the last bucket
	    #  is removed from the node... take a lock to make sure only one
	    #  process executes that code
	    ocf_take_lock $CIP_lockfile
	    ocf_release_lock_on_exit $CIP_lockfile
	fi
	
	if [ -f "$SENDARPPIDFILE" ] ; then
		kill `cat "$SENDARPPIDFILE"`
		if [ $? -ne 0 ]; then
			ocf_log warn "Could not kill previously running send_arp for $OCF_RESKEY_ip"
		else
			ocf_log info "killed previously running send_arp for $OCF_RESKEY_ip"
		fi
		rm -f "$SENDARPPIDFILE"
	fi
	local ip_status=`ip_served`
	ocf_log info "IP status = $ip_status, IP_CIP=$IP_CIP"

	if [ $ip_status = "no" ]; then
		: Requested interface not in use
		exit $OCF_SUCCESS
	fi

	if [ -n "$IP_CIP" ] && [ $ip_status != "partial2" ]; then
		if [ $ip_status = "partial" ]; then
			exit $OCF_SUCCESS
		fi
		echo "-$IP_INC_NO" >$IP_CIP_FILE
		if [ "x$(cat $IP_CIP_FILE)" = "x" ]; then
			ocf_log info $OCF_RESKEY_ip, $IP_CIP_HASH
			i=1
			while [ $i -le $IP_INC_GLOBAL ]; do
				ocf_log info $i
				$IPADDR2_CIP_IPTABLES -D INPUT -d $OCF_RESKEY_ip -i $NIC -j CLUSTERIP \
					--new \
					--clustermac $IF_MAC \
					--total-nodes $IP_INC_GLOBAL \
					--local-node $i \
					--hashmode $IP_CIP_HASH
				i=`expr $i + 1`
			done
		else
			ip_del_if="no"		
		fi
	fi
	
	if [ "$ip_del_if" = "yes" ]; then
		delete_interface $OCF_RESKEY_ip $NIC $NETMASK
		if [ $? -ne 0 ]; then
			ocf_exit_reason "Unable to remove IP [${OCF_RESKEY_ip} from interface [ $NIC ]"
			exit $OCF_ERR_GENERIC
		fi
	
		if ocf_is_true ${OCF_RESKEY_lvs_support}; then
			restore_loopback "$OCF_RESKEY_ip"
		fi
	fi

	exit $OCF_SUCCESS
}

ip_monitor() {
	# TODO: Implement more elaborate monitoring like checking for
	# interface health maybe via a daemon like FailSafe etc...

	local ip_status=`ip_served`
	case $ip_status in
	ok)
		run_arp_sender refresh
		return $OCF_SUCCESS
		;;
	partial|no|partial2)
		exit $OCF_NOT_RUNNING
		;;
	*)
		# Errors on this interface?
		return $OCF_ERR_GENERIC
		;;
	esac
}

# make sure that we have something to send ARPs with
set_send_arp_program() {
    ARP_SENDER=send_arp
    if [ -n "$OCF_RESKEY_arp_sender" ]; then
	case "$OCF_RESKEY_arp_sender" in
	send_arp)
	    check_binary $SENDARP
	;;
	iputils_arping)
	    check_binary arping
	;;
	libnet_arping)
	    check_binary arping
	;;
	ipoibarping)
	    check_binary ipoibarping
	;;
	*)
	    ocf_exit_reason "unrecognized arp_sender value: $OCF_RESKEY_arp_sender"
	    exit $OCF_ERR_CONFIGURED
	;;
	esac
	ARP_SENDER="$OCF_RESKEY_arp_sender"
    else
	if is_infiniband; then
	    ARP_SENDER=ipoibarping
	    if ! have_binary ipoibarping; then
	    	[ "$__OCF_ACTION" = start ] &&
		    ocf_log warn "using send_arp for infiniband because ipoibarping is not available (set arp_sender to \"send_arp\" to suppress this message)"
		check_binary $SENDARP
		ARP_SENDER=send_arp
	    fi
	fi
    fi
}

ip_validate() {
    check_binary $IP2UTIL
    IP_CIP=

    if [ -n "$OCF_RESKEY_network_namespace" ]; then
        OCF_RESKEY_network_namespace= exec $IP2UTIL netns exec "$OCF_RESKEY_network_namespace" "$0" "$__OCF_ACTION"
    fi

    ip_init

    set_send_arp_program

    if [ -n "$IP_CIP" ]; then
        if have_binary "$IPTABLES_LEGACY"; then
            IPADDR2_CIP_IPTABLES="$IPTABLES_LEGACY"
        fi
        check_binary "$IPADDR2_CIP_IPTABLES"
        check_binary $MODPROBE
    fi

# $BASEIP, $NETMASK, $NIC , $IP_INC_GLOBAL, and $BRDCAST have been checked within ip_init,
# do not bother here.

    if ocf_is_true "$OCF_RESKEY_unique_clone_address" &&
	    ! ocf_is_true "$OCF_RESKEY_CRM_meta_globally_unique"; then
	ocf_exit_reason "unique_clone_address makes sense only with meta globally_unique set"
	exit $OCF_ERR_CONFIGURED
    fi

    if ocf_is_decimal "$OCF_RESKEY_arp_interval" && [ $OCF_RESKEY_arp_interval -gt 0 ]; then
	:
    else
	ocf_exit_reason "Invalid OCF_RESKEY_arp_interval [$OCF_RESKEY_arp_interval]"
	exit $OCF_ERR_CONFIGURED
    fi

    if ocf_is_decimal "$OCF_RESKEY_arp_count" && [ $OCF_RESKEY_arp_count -gt 0 ]; then
	:
    else
	ocf_exit_reason "Invalid OCF_RESKEY_arp_count [$OCF_RESKEY_arp_count]"
	exit $OCF_ERR_CONFIGURED
    fi

    if [ -z "$OCF_RESKEY_preferred_lft" ]; then
	ocf_exit_reason "Empty value is invalid for OCF_RESKEY_preferred_lft"
	exit $OCF_ERR_CONFIGURED
    fi

    if [ -n "$IP_CIP" ]; then

	local valid=1

	case $IP_CIP_HASH in
	sourceip|sourceip-sourceport|sourceip-sourceport-destport)
		;;
	*)
		ocf_exit_reason "Invalid OCF_RESKEY_clusterip_hash [$IP_CIP_HASH]"
		exit $OCF_ERR_CONFIGURED
		;;
	esac

	if ocf_is_true ${OCF_RESKEY_lvs_support}; then
		ocf_exit_reason "LVS and load sharing not advised to try"
		exit $OCF_ERR_CONFIGURED
	fi

	case $IF_MAC in
	[0-9a-zA-Z][13579bBdDfF][!0-9a-zA-Z][0-9a-zA-Z][0-9a-zA-Z][!0-9a-zA-Z][0-9a-zA-Z][0-9a-zA-Z][!0-9a-zA-Z][0-9a-zA-Z][0-9a-zA-Z][!0-9a-zA-Z][0-9a-zA-Z][0-9a-zA-Z][!0-9a-zA-Z][0-9a-zA-Z][0-9a-zA-Z])
		;;
	*)
		valid=0
		;;
	esac

	if [ $valid -eq 0 ]; then
	  ocf_exit_reason "Invalid IF_MAC [$IF_MAC]"
	  exit $OCF_ERR_CONFIGURED
	fi

    fi
}

if ocf_is_true "$OCF_RESKEY_unique_clone_address"; then
    prefix=`echo $OCF_RESKEY_ip | awk -F. '{print $1"."$2"."$3}'`
    suffix=`echo $OCF_RESKEY_ip | awk -F. '{print $4}'`
    suffix=`expr ${OCF_RESKEY_CRM_meta_clone:-0} + $suffix`
    OCF_RESKEY_ip="$prefix.$suffix"
fi

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

ip_validate

case $__OCF_ACTION in
start)		ip_start
		;;
stop)		ip_stop
		;;
status)		ip_status=`ip_served`
		if [ $ip_status = "ok" ]; then
			echo "running"
			exit $OCF_SUCCESS
		else
			echo "stopped"
			exit $OCF_NOT_RUNNING
		fi
		;;
monitor)	ip_monitor
		;;
validate-all)	;;
*)		ip_usage
		exit $OCF_ERR_UNIMPLEMENTED
		;;
esac
# vi:sw=4:ts=8: