diff --git a/libexec/rc/network.subr b/libexec/rc/network.subr
index 257643f48ba5..931fbec19a60 100644
--- a/libexec/rc/network.subr
+++ b/libexec/rc/network.subr
@@ -1,1770 +1,1770 @@
 #
 # Copyright (c) 2003 The FreeBSD Project. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions
 # are met:
 # 1. Redistributions of source code must retain the above copyright
 #    notice, this list of conditions and the following disclaimer.
 # 2. Redistributions in binary form must reproduce the above copyright
 #    notice, this list of conditions and the following disclaimer in the
 #    documentation and/or other materials provided with the distribution.
 #
 # THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
 # ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 # ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
 # FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 # DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 # OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 # HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 # LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 # OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 # SUCH DAMAGE.
 #
 #
 IFCONFIG_CMD="/sbin/ifconfig"
 : ${netif_ipexpand_max:=2048}
 
 #
 # Subroutines commonly used from network startup scripts.
 # Requires that rc.conf be loaded first.
 #
 
 # ifn_start ifn
 #	Bring up and configure an interface.  If some configuration is
 #	applied, print the interface configuration.
 #
 ifn_start()
 {
 	local ifn cfg
 	ifn="$1"
 	cfg=1
 
 	[ -z "$ifn" ] && err 1 "ifn_start called without an interface"
 
 	ifscript_up ${ifn} && cfg=0
 	ifconfig_up ${ifn} && cfg=0
 	if ! noafif $ifn; then
-		afexists inet && ipv4_up ${ifn} && cfg=0
 		afexists inet6 && ipv6_up ${ifn} && cfg=0
+		afexists inet && ipv4_up ${ifn} && cfg=0
 	fi
 	childif_create ${ifn} && cfg=0
 
 	return $cfg
 }
 
 # ifn_stop ifn
 #	Shutdown and de-configure an interface.  If action is taken,
 #	print the interface name.
 #
 ifn_stop()
 {
 	local ifn cfg
 	ifn="$1"
 	cfg=1
 
 	[ -z "$ifn" ] && err 1 "ifn_stop called without an interface"
 
 	if ! noafif $ifn; then
-		afexists inet6 && ipv6_down ${ifn} && cfg=0
 		afexists inet && ipv4_down ${ifn} && cfg=0
+		afexists inet6 && ipv6_down ${ifn} && cfg=0
 	fi
 	ifconfig_down ${ifn} && cfg=0
 	ifscript_down ${ifn} && cfg=0
 	childif_destroy ${ifn} && cfg=0
 
 	return $cfg
 }
 
 # ifn_vnetup ifn
 #	Move ifn to the specified vnet jail.
 #
 ifn_vnetup()
 {
 
 	ifn_vnet0 $1 vnet
 }
 
 # ifn_vnetdown ifn
 #	Reclaim ifn from the specified vnet jail.
 #
 ifn_vnetdown()
 {
 
 	ifn_vnet0 $1 -vnet
 }
 
 # ifn_vnet0 ifn action
 #	Helper function for ifn_vnetup and ifn_vnetdown.
 #
 ifn_vnet0()
 {
 	local _ifn _cfg _action _vnet
 	_ifn="$1"
 	_action="$2"
 	_cfg=1
 
 	if _vnet=$(vnetif $_ifn); then
 		${IFCONFIG_CMD} $_ifn $_action $_vnet && _cfg=0
 	fi
 
 	return $_cfg
 }
 
 # ifconfig_up if
 #	Evaluate ifconfig(8) arguments for interface $if and
 #	run ifconfig(8) with those arguments. It returns 0 if
 #	arguments were found and executed or 1 if the interface
 #	had no arguments.  Pseudo arguments DHCP and WPA are handled
 #	here.
 #
 ifconfig_up()
 {
 	local _cfg _ifconfig_descr _ipv6_opts ifconfig_args 
 	_cfg=1
 
 	# Make sure lo0 always comes up.
 	if [ "$1" = "lo0" ]; then
 		_cfg=0
 	fi
 
 	# inet6 specific
 	if ! noafif $1 && afexists inet6; then
 		if checkyesno ipv6_activate_all_interfaces; then
 			_ipv6_opts="-ifdisabled"
 		fi
 
 		# backward compatibility: $ipv6_enable
 		case $ipv6_enable in
 		[Yy][Ee][Ss]|[Tt][Rr][Uu][Ee]|[Oo][Nn]|1)
 			case $1 in
 			bridge[0-9]*)
 				# No accept_rtadv by default on if_bridge(4)
 				# to avoid a conflict with the member
 				# interfaces.
 			;;
 			*)
 				if ! checkyesno ipv6_gateway_enable; then
 					_ipv6_opts="${_ipv6_opts} accept_rtadv"
 				fi
 			;;
 			esac
 		;;
 		esac
 
 		case $ipv6_cpe_wanif in
 		$1)
 			_ipv6_opts="${_ipv6_opts} -no_radr accept_rtadv"
 		;;
 		esac
 
 		if [ -n "${_ipv6_opts}" ]; then
 			${IFCONFIG_CMD} $1 inet6 ${_ipv6_opts}
 		fi
 	fi
 
 	# ifconfig_IF
 	ifconfig_args=`ifconfig_getargs $1`
 	if [ -n "${ifconfig_args}" ]; then
 		eval ${IFCONFIG_CMD} $1 ${ifconfig_args}
 		_cfg=0
 	fi
 
 	# inet6 specific
 	if ! noafif $1 && afexists inet6; then
 		# ifconfig_IF_ipv6
 		ifconfig_args=`ifconfig_getargs $1 ipv6`
 		if [ -n "${ifconfig_args}" ]; then
 			# backward compatibility: inet6 keyword
 			case "${ifconfig_args}" in
 			:*|[0-9a-fA-F]*:*)
 				warn "\$ifconfig_$1_ipv6 needs leading" \
 				    "\"inet6\" keyword for an IPv6 address."
 				ifconfig_args="inet6 ${ifconfig_args}"
 			;;
 			esac
 			${IFCONFIG_CMD} $1 inet6 -ifdisabled
 			eval ${IFCONFIG_CMD} $1 ${ifconfig_args}
 			_cfg=0
 		fi
 
 		# $ipv6_prefix_IF will be handled in
 		# ipv6_prefix_hostid_addr_common().
 		ifconfig_args=`get_if_var $1 ipv6_prefix_IF`
 		if [ -n "${ifconfig_args}" ]; then
 			${IFCONFIG_CMD} $1 inet6 -ifdisabled
 			_cfg=0
 		fi
 
 		# backward compatibility: $ipv6_ifconfig_IF
 		ifconfig_args=`get_if_var $1 ipv6_ifconfig_IF`
 		if [ -n "${ifconfig_args}" ]; then
 			warn "\$ipv6_ifconfig_$1 is obsolete." \
 			    "  Use ifconfig_$1_ipv6 instead."
 			${IFCONFIG_CMD} $1 inet6 -ifdisabled
 			eval ${IFCONFIG_CMD} $1 inet6 ${ifconfig_args}
 			_cfg=0
 		fi
 	fi
 
 	ifalias $1 link alias
 	ifalias $1 ether alias
 
 	_ifconfig_descr=`get_if_var $1 ifconfig_IF_descr`
 	if [ -n "${_ifconfig_descr}" ]; then
 		${IFCONFIG_CMD} $1 description "${_ifconfig_descr}"
 	fi
 
 	if wpaif $1; then
 		/etc/rc.d/wpa_supplicant start $1
 		_cfg=0		# XXX: not sure this should count
 	elif hostapif $1; then
 		/etc/rc.d/hostapd start $1
 		_cfg=0
 	elif [ ${_cfg} -eq 0 ]; then
 		${IFCONFIG_CMD} $1 up
 	fi
 
 	if ! noafif $1 && afexists inet6; then
 		ipv6_accept_rtadv_up $1 && _cfg=0
 	fi
 
 	if dhcpif $1; then
 		if [ $_cfg -ne 0 ] ; then
 			${IFCONFIG_CMD} $1 up
 		fi
 		if syncdhcpif $1; then
 			/etc/rc.d/dhclient start $1
 		fi
 		_cfg=0
 	fi
 
 	return $_cfg
 }
 
 # ifconfig_down if
 #	returns 1 if wpa_supplicant or dhclient was stopped or
 #	the interface exists.
 #
 ifconfig_down()
 {
 	local _cfg
 	_cfg=1
 
 	if wpaif $1; then
 		/etc/rc.d/wpa_supplicant stop $1
 		_cfg=0
 	elif hostapif $1; then
 		/etc/rc.d/hostapd stop $1
 		_cfg=0
 	elif dhcpif $1; then
 		/etc/rc.d/dhclient stop $1
 		_cfg=0
 	fi
 
 	if ifexists $1; then
 		${IFCONFIG_CMD} $1 down
 		_cfg=0
 	fi
 
 	return $_cfg
 }
 
 # get_if_var if var [default]
 #	Return the value of the pseudo-hash corresponding to $if where
 #	$var is a string containg the sub-string "IF" which will be
 #	replaced with $if after the characters defined in _punct are
 #	replaced with '_'. If the variable is unset, replace it with
 #	$default if given.
 get_if_var()
 {
 	local _if _punct _punct_c _var _default prefix suffix
 
 	if [ $# -ne 2 -a $# -ne 3 ]; then
 		err 3 'USAGE: get_if_var name var [default]'
 	fi
 
 	_if=$1
 	_punct=".-/+"
 	ltr ${_if} "${_punct}" '_' _if
 	_var=$2
 	_default=$3
 
 	prefix=${_var%%IF*}
 	suffix=${_var##*IF}
 	eval echo \${${prefix}${_if}${suffix}-${_default}}
 }
 
 # _ifconfig_getargs if [af]
 #	Prints the arguments for the supplied interface to stdout.
 #	Returns 1 if empty.  In general, ifconfig_getargs should be used
 #	outside this file.
 _ifconfig_getargs()
 {
 	local _ifn _af
 	_ifn=$1
 	_af=${2+_$2}
 
 	if [ -z "$_ifn" ]; then
 		return 1
 	fi
 
 	get_if_var $_ifn ifconfig_IF$_af "$ifconfig_DEFAULT"
 }
 
 # ifconfig_getargs if [af]
 #	Takes the result from _ifconfig_getargs and removes pseudo
 #	args such as DHCP and WPA.
 ifconfig_getargs()
 {
 	local _tmpargs _arg _args _vnet
 	_tmpargs=`_ifconfig_getargs $1 $2`
 	if [ $? -eq 1 ]; then
 		return 1
 	fi
 	_args=
 	_vnet=0
 
 	for _arg in $_tmpargs; do
 		case $_arg:$_vnet in
 		[Dd][Hh][Cc][Pp]:0) ;;
 		[Nn][Oo][Aa][Uu][Tt][Oo]:0) ;;
 		[Nn][Oo][Ss][Yy][Nn][Cc][Dd][Hh][Cc][Pp]:0) ;;
 		[Ss][Yy][Nn][Cc][Dd][Hh][Cc][Pp]:0) ;;
 		[Ww][Pp][Aa]:0) ;;
 		[Hh][Oo][Ss][Tt][Aa][Pp]:0) ;;
 		vnet:0)	_vnet=1 ;;
 		*:1)	_vnet=0 ;;
 		*:0)
 			_args="$_args $_arg"
 		;;
 		esac
 	done
 
 	echo $_args
 }
 
 # autoif
 #	Returns 0 if the interface should be automatically configured at
 #	boot time and 1 otherwise.
 autoif()
 {
 	local _tmpargs _arg
 	_tmpargs=`_ifconfig_getargs $1`
 
 	for _arg in $_tmpargs; do
 		case $_arg in
 		[Nn][Oo][Aa][Uu][Tt][Oo])
 			return 1
 			;;
 		esac
 	done
 
 	return 0
 }
 
 # dhcpif if
 #	Returns 0 if the interface is a DHCP interface and 1 otherwise.
 dhcpif()
 {
 	local _tmpargs _arg
 	_tmpargs=`_ifconfig_getargs $1`
 
 	case $1 in
 	lo[0-9]*|\
 	stf[0-9]*|\
 	lp[0-9]*|\
 	sl[0-9]*)
 		return 1
 		;;
 	esac
 	if noafif $1; then
 		return 1
 	fi
 
 	for _arg in $_tmpargs; do
 		case $_arg in
 		[Dd][Hh][Cc][Pp])
 			return 0
 			;;
 		[Nn][Oo][Ss][Yy][Nn][Cc][Dd][Hh][Cc][Pp])
 			return 0
 			;;
 		[Ss][Yy][Nn][Cc][Dd][Hh][Cc][Pp])
 			return 0
 			;;
 		esac
 	done
 
 	return 1
 }
 
 # syncdhcpif
 #	Returns 0 if the interface should be configured synchronously and
 #	1 otherwise.
 syncdhcpif()
 {
 	local _tmpargs _arg
 	_tmpargs=`_ifconfig_getargs $1`
 
 	if noafif $1; then
 		return 1
 	fi
 
 	for _arg in $_tmpargs; do
 		case $_arg in
 		[Nn][Oo][Ss][Yy][Nn][Cc][Dd][Hh][Cc][Pp])
 			return 1
 			;;
 		[Ss][Yy][Nn][Cc][Dd][Hh][Cc][Pp])
 			return 0
 			;;
 		esac
 	done
 
 	checkyesno synchronous_dhclient
 }
 
 # wpaif if
 #	Returns 0 if the interface is a WPA interface and 1 otherwise.
 wpaif()
 {
 	local _tmpargs _arg
 	_tmpargs=`_ifconfig_getargs $1`
 
 	for _arg in $_tmpargs; do
 		case $_arg in
 		[Ww][Pp][Aa])
 			return 0
 			;;
 		esac
 	done
 
 	return 1
 }
 
 # hostapif if
 #	Returns 0 if the interface is a HOSTAP interface and 1 otherwise.
 hostapif()
 {
 	local _tmpargs _arg
 	_tmpargs=`_ifconfig_getargs $1`
 
 	for _arg in $_tmpargs; do
 		case $_arg in
 		[Hh][Oo][Ss][Tt][Aa][Pp])
 			return 0
 			;;
 		esac
 	done
 
 	return 1
 }
 
 # vnetif if
 #	Returns 0 and echo jail if "vnet" keyword is specified on the
 #	interface, and 1 otherwise.
 vnetif()
 {
 	local _tmpargs _arg _vnet
 	_tmpargs=`_ifconfig_getargs $1`
 
 	_vnet=0
 	for _arg in $_tmpargs; do
 		case $_arg:$_vnet in
 		vnet:0)	_vnet=1 ;;
 		*:1)	echo $_arg; return 0 ;;
 		esac
 	done
 
 	return 1
 }
 
 # afexists af
 #	Returns 0 if the address family is enabled in the kernel
 #	1 otherwise.
 afexists()
 {
 	local _af
 	_af=$1
 
 	case ${_af} in
 	inet|inet6)
 		check_kern_features ${_af}
 		;;
 	link|ether)
 		return 0
 		;;
 	*)
 		err 1 "afexists(): Unsupported address family: $_af"
 		;;
 	esac
 }
 
 # noafif if
 #	Returns 0 if the interface has no af configuration and 1 otherwise.
 noafif()
 {
 	local _if
 	_if=$1
 
 	case $_if in
 	pflog[0-9]*|\
 	pfsync[0-9]*|\
 	usbus[0-9]*|\
 	an[0-9]*|\
 	ath[0-9]*|\
 	ipw[0-9]*|\
 	ipfw[0-9]*|\
 	iwi[0-9]*|\
 	iwn[0-9]*|\
 	ral[0-9]*|\
 	wi[0-9]*|\
 	wl[0-9]*|\
 	wpi[0-9]*)
 		return 0
 		;;
 	esac
 
 	return 1
 }
 
 # ipv6if if
 #	Returns 0 if the interface should be configured for IPv6 and
 #	1 otherwise.
 ipv6if()
 {
 	local _if _tmpargs i
 	_if=$1
 
 	if ! afexists inet6; then
 		return 1
 	fi
 
 	# lo0 is always IPv6-enabled
 	case $_if in
 	lo0)
 		return 0
 		;;
 	esac
 
 	case "${ipv6_network_interfaces}" in
 	$_if|"$_if "*|*" $_if"|*" $_if "*|[Aa][Uu][Tt][Oo])
 		# True if $ifconfig_IF_ipv6 is defined.
 		_tmpargs=`_ifconfig_getargs $_if ipv6`
 		if [ -n "${_tmpargs}" ]; then
 			return 0
 		fi
 
 		# True if $ipv6_prefix_IF is defined.
 		_tmpargs=`get_if_var $_if ipv6_prefix_IF`
 		if [ -n "${_tmpargs}" ]; then
 			return 0
 		fi
 
 		# backward compatibility: True if $ipv6_ifconfig_IF is defined.
 		_tmpargs=`get_if_var $_if ipv6_ifconfig_IF`
 		if [ -n "${_tmpargs}" ]; then
 			return 0
 		fi
 		;;
 	esac
 
 	return 1
 }
 
 # ipv6_autoconfif if
 #	Returns 0 if the interface should be configured for IPv6 with
 #	Stateless Address Configuration; 1 otherwise.
 ipv6_autoconfif()
 {
 	local _if _tmpargs _arg
 	_if=$1
 
 	case $_if in
 	lo[0-9]*|\
 	stf[0-9]*|\
 	lp[0-9]*|\
 	sl[0-9]*)
 		return 1
 		;;
 	esac
 	if noafif $_if; then
 		return 1
 	fi
 	if ! ipv6if $_if; then
 		return 1
 	fi
 	if checkyesno ipv6_gateway_enable; then
 		return 1
 	fi
 	_tmpargs=`get_if_var $_if ipv6_prefix_IF`
 	if [ -n "${_tmpargs}" ]; then
 		return 1
 	fi
 	# backward compatibility: $ipv6_enable
 	case $ipv6_enable in
 	[Yy][Ee][Ss]|[Tt][Rr][Uu][Ee]|[Oo][Nn]|1)
 		if checkyesno ipv6_gateway_enable; then
 			return 1
 		fi
 		case $1 in
 		bridge[0-9]*)
 			# No accept_rtadv by default on if_bridge(4)
 			# to avoid a conflict with the member
 			# interfaces.
 			return 1
 		;;
 		*)
 			return 0
 		;;
 		esac
 	;;
 	esac
 
 	_tmpargs=`_ifconfig_getargs $_if ipv6`
 	for _arg in $_tmpargs; do
 		case $_arg in
 		accept_rtadv)
 			return 0
 			;;
 		esac
 	done
 
 	# backward compatibility: $ipv6_ifconfig_IF
 	_tmpargs=`get_if_var $_if ipv6_ifconfig_IF`
 	for _arg in $_tmpargs; do
 		case $_arg in
 		accept_rtadv)
 			return 0
 			;;
 		esac
 	done
 
 	return 1
 }
 
 # ifexists if
 #	Returns 0 if the interface exists and 1 otherwise.
 ifexists()
 {
 	[ -z "$1" ] && return 1
 	${IFCONFIG_CMD} -n $1 > /dev/null 2>&1
 }
 
 # ipv4_up if
 #	add IPv4 addresses to the interface $if
 ipv4_up()
 {
 	local _if _ret
 	_if=$1
 	_ret=1
 
 	# Add 127.0.0.1/8 to lo0 unless otherwise specified.
 	if [ "${_if}" = "lo0" ]; then
 		ifconfig_args=`get_if_var ${_if} ifconfig_IF`
 		if [ -z "${ifconfig_args}" ]; then
 			${IFCONFIG_CMD} ${_if} inet 127.0.0.1/8 alias
 		fi
 	fi
 	ifalias ${_if} inet alias && _ret=0
 
 	return $_ret
 }
 
 # ipv6_up if
 #	add IPv6 addresses to the interface $if
 ipv6_up()
 {
 	local _if _ret
 	_if=$1
 	_ret=1
 
 	if ! ipv6if $_if; then
 		return 0
 	fi
 
 	ifalias ${_if} inet6 alias && _ret=0
 	ipv6_prefix_hostid_addr_common ${_if} alias && _ret=0
 
 	return $_ret
 }
 
 # ipv4_down if
 #	remove IPv4 addresses from the interface $if
 ipv4_down()
 {
 	local _if _ifs _ret inetList oldifs _inet
 	_if=$1
 	_ifs="^"
 	_ret=1
 
 	ifalias ${_if} inet -alias && _ret=0
 
 	inetList="`${IFCONFIG_CMD} ${_if} | grep 'inet ' | tr "\n\t" "$_ifs"`"
 
 	oldifs="$IFS"
 	IFS="$_ifs"
 	for _inet in $inetList ; do
 		# get rid of extraneous line
 		case $_inet in
 		inet[[:space:]]*)	;;
 		*)		continue ;;
 		esac
 
 		_inet=`expr "$_inet" : '.*\(inet \([0-9]\{1,3\}\.\)\{3\}[0-9]\{1,3\}\).*'`
 
 		IFS="$oldifs"
 		${IFCONFIG_CMD} ${_if} ${_inet} delete
 		IFS="$_ifs"
 		_ret=0
 	done
 	IFS="$oldifs"
 
 	return $_ret
 }
 
 # ipv6_down if
 #	remove IPv6 addresses from the interface $if
 ipv6_down()
 {
 	local _if _ifs _ret inetList oldifs _inet6
 	_if=$1
 	_ifs="^"
 	_ret=1
 
 	if ! ipv6if $_if; then
 		return 0
 	fi
 
 	ipv6_accept_rtadv_down ${_if} && _ret=0
 	ipv6_prefix_hostid_addr_common ${_if} -alias && _ret=0
 	ifalias ${_if} inet6 -alias && _ret=0
 
 	inetList="`${IFCONFIG_CMD} ${_if} | grep 'inet6 ' | tr "\n\t" "$_ifs"`"
 
 	oldifs="$IFS"
 	IFS="$_ifs"
 	for _inet6 in $inetList ; do
 		# get rid of extraneous line
 		case $_inet6 in
 		inet6[[:space:]]*)	;;
 		*)		continue ;;
 		esac
 
 		_inet6=`expr "$_inet6" : '.*\(inet6 \([0-9a-f:]*\)\).*'`
 
 		IFS="$oldifs"
 		${IFCONFIG_CMD} ${_if} ${_inet6} -alias
 		IFS="$_ifs"
 		_ret=0
 	done
 	IFS="$oldifs"
 
 	return $_ret
 }
 
 # ifalias if af action
 #	Configure or remove aliases for network interface $if.
 #	It returns 0 if at least one alias was configured or
 #	removed, or 1 if there were none.
 #
 ifalias()
 {
 	local _ret
 	_ret=1
 
 	afexists $2 || return $_ret
 
 	case "$2" in
 	inet|inet6|link|ether)
 		ifalias_af_common $1 $2 $3 && _ret=0
 		;;
 	esac
 
 	return $_ret
 }
 
 # ifalias_expand_addr af action addr
 #	Expand address range ("N-M") specification in addr.
 #	"addr" must not include an address-family keyword.
 #	The results will include an address-family keyword.
 #
 ifalias_expand_addr()
 {
 	local _af _action
 
 	_af=$1
 	_action=$2
 	shift 2
 
 	afexists $_af || return
 	ifalias_expand_addr_$_af $_action $*
 }
 
 # ifalias_expand_addr_inet action addr
 #	Helper function for ifalias_expand_addr().  Handles IPv4.
 #
 ifalias_expand_addr_inet()
 {
 	local _action _arg _cidr _cidr_addr _exargs
 	local _ipaddr _plen _range _iphead _iptail _iplow _iphigh _ipcount
 	local _retstr _c
 	_action=$1
 	_arg=$2
 	shift 2
 	_exargs=$*
 	_retstr=
 
 	case $_action:$_arg:$_exargs in
 	*:*--*)		return ;;	# invalid
 	tmp:*[0-9]-[0-9]*:*)		# to be expanded
 		_action="alias"
 	;;
 	*:*[0-9]-[0-9]*:*)		# to be expanded
 	;;
 	tmp:*:*netmask*)		# already expanded w/ netmask option
 		echo ${_arg%/[0-9]*} $_exargs && return
 	;;
 	tmp:*:*)			# already expanded w/o netmask option
 		echo $_arg $_exargs && return
 	;;
 	*:*:*netmask*)			# already expanded w/ netmask option
 		echo inet ${_arg%/[0-9]*} $_exargs && return
 	;;
 	*:*:*)				# already expanded w/o netmask option
 		echo inet $_arg $_exargs && return
 	;;
 	esac
 
 	for _cidr in $_arg; do
 		_ipaddr=${_cidr%%/*}
 		_plen=${_cidr##*/}
 		# When subnet prefix length is not specified, use /32.
 		case $_plen in
 		$_ipaddr)	_plen=32 ;;	# "/" character not found
 		esac
 
 		OIFS=$IFS
 		IFS=. set -- $_ipaddr
 		_range=
 		_iphead=
 		_iptail=
 		for _c in $@; do
 			case $_range:$_c in
 			:[0-9]*-[0-9]*)
 				_range=$_c
 			;;
 			:*)
 				_iphead="${_iphead}${_iphead:+.}${_c}"
 			;;
 			*:*)
 				_iptail="${_iptail}${_iptail:+.}${_c}"
 			;;
 			esac
 		done
 		IFS=$OIFS
 		_iplow=${_range%-*}
 		_iphigh=${_range#*-}
 
 		# clear netmask when removing aliases
 		if [ "$_action" = "-alias" ]; then
 			_plen=""
 		fi
 
 		_ipcount=$_iplow
 		while [ "$_ipcount" -le "$_iphigh" ]; do
 			_retstr="${_retstr} ${_iphead}${_iphead:+.}${_ipcount}${_iptail:+.}${_iptail}${_plen:+/}${_plen}"
 			if [ $_ipcount -gt $(($_iplow + $netif_ipexpand_max)) ]; then
 				warn "Range specification is too large (${_iphead}${_iphead:+.}${_iplow}${_iptail:+.}${_iptail}-${_iphead}${_iphead:+.}${_iphigh}${_iptail:+.}${_iptail}).  ${_iphead}${_iphead:+.}${_iplow}${_iptail:+.}${_iptail}-${_iphead}${_iphead:+.}${_ipcount}${_iptail:+.}${_iptail} was processed.  Increase \$netif_ipexpand_max in rc.conf."
 				break
 			else
 				_ipcount=$(($_ipcount + 1))
 			fi
 			# Forcibly set /32 for remaining aliases.
 			_plen=32
 		done
 	done
 
 	for _c in $_retstr; do
 		ifalias_expand_addr_inet $_action $_c $_exargs
 	done
 }
 
 # ifalias_expand_addr_inet6 action addr
 #	Helper function for ifalias_expand_addr().  Handles IPv6.
 #
 ifalias_expand_addr_inet6()
 {
 	local _action _arg _cidr _cidr_addr _exargs
 	local _ipaddr _plen _ipleft _ipright _iplow _iphigh _ipcount
 	local _ipv4part
 	local _retstr _c
 	_action=$1
 	_arg=$2
 	shift 2
 	_exargs=$*
 	_retstr=
 
 	case $_action:$_arg:$_exargs in
 	*:*--*:*)	return ;;	# invalid
 	tmp:*[0-9a-zA-Z]-[0-9a-zA-Z]*:*)# to be expanded
 		_action="alias"
 	;;
 	*:*[0-9a-zA-Z]-[0-9a-zA-Z]*:*)	# to be expanded
 	;;
 	tmp:*:*prefixlen*)	# already expanded w/ prefixlen option
 		echo ${_arg%/[0-9]*} $_exargs && return
 	;;
 	tmp:*:*)		# already expanded w/o prefixlen option
 		echo $_arg $_exargs && return
 	;;
 	*:*:*prefixlen*)	# already expanded w/ prefixlen option
 		echo inet6 ${_arg%/[0-9]*} $_exargs && return
 	;;
 	*:*:*)			# already expanded w/o prefixlen option
 		echo inet6 $_arg $_exargs && return
 	;;
 	esac
 
 	for _cidr in $_arg; do
 		_ipaddr="${_cidr%%/*}"
 		_plen="${_cidr##*/}"
 
 		case $_action:$_ipaddr:$_cidr in
 		-alias:*:*)		unset _plen ;;
 		*:$_cidr:$_ipaddr)	unset _plen ;;
 		esac
 
 		if [ "${_ipaddr%:*.*.*.*}" = "$_ipaddr" ]; then
 			# Handle !v4mapped && !v4compat addresses.
 
 			# The default prefix length is 64.
 			case $_ipaddr:$_cidr in
 			$_cidr:$_ipaddr)	_plen="64" ;;
 			esac
 			_ipleft=${_ipaddr%-*}
 			_ipright=${_ipaddr#*-}
 			_iplow=${_ipleft##*:}
 			_iphigh=${_ipright%%:*}
 			_ipleft=${_ipleft%:*}
 			_ipright=${_ipright#*:}
 
 			if [ "$_iphigh" = "$_ipright" ]; then
 				unset _ipright
 			else
 				_ipright=:$_ipright
 			fi
 
 			if [ -n "$_iplow" -a -n "$_iphigh" ]; then
 				_iplow=$((0x$_iplow))
 				_iphigh=$((0x$_iphigh))
 				_ipcount=$_iplow
 				while [ $_ipcount -le $_iphigh ]; do
 					_r=`printf "%s:%04x%s%s" \
 					    $_ipleft $_ipcount $_ipright \
 					    ${_plen:+/}$_plen`
 					_retstr="$_retstr $_r"
 					if [ $_ipcount -gt $(($_iplow + $netif_ipexpand_max)) ]
 					then
 						warn "Range specification is too large $(printf '(%s:%x%s-%s:%x%s)' "$_ipleft" "$_iplow" "$_ipright" "$_ipleft" "$_iphigh" "$_ipright"). $(printf '%s:%x%s-%s:%x%s' "$_ipleft" "$_iplow" "$_ipright" "$_ipleft" "$_ipcount" "$_ipright") was processed.  Increase \$netif_ipexpand_max in rc.conf."
 						break
 					else
 						_ipcount=$(($_ipcount + 1))
 					fi
 				done
 			else
 				_retstr="${_ipaddr}${_plen:+/}${_plen}"
 			fi
 
 			for _c in $_retstr; do
 				ifalias_expand_addr_inet6 $_action $_c $_exargs
 			done
 		else
 			# v4mapped/v4compat should handle as an IPv4 alias
 			_ipv4part=${_ipaddr##*:}
 
 			# Adjust prefix length if any.  If not, set the
 			# default prefix length as 32.
 			case $_ipaddr:$_cidr in
 			$_cidr:$_ipaddr)	_plen=32 ;;
 			*)			_plen=$(($_plen - 96)) ;;
 			esac
 
 			_retstr=`ifalias_expand_addr_inet \
 			    tmp ${_ipv4part}${_plen:+/}${_plen}`
 			for _c in $_retstr; do
 				ifalias_expand_addr_inet $_action $_c $_exargs
 			done
 		fi
 	done
 }
 
 # ifalias_af_common_handler if af action args
 #	Helper function for ifalias_af_common().
 #
 ifalias_af_common_handler()
 {
 	local _ret _if _af _action _args _c _tmpargs
 
 	_ret=1
 	_if=$1
 	_af=$2
 	_action=$3
 	shift 3
 	_args=$*
 
 	case $_args in
 	${_af}[[:space:]]*)	;;
 	*)	return	;;
 	esac
 
 	# link(ether) does not support address removal.
 	case $_af:$_action in
 	link:-alias|ether:-alias)	return ;;
 	esac
 
 	_tmpargs=
 	for _c in $_args; do
 		case $_c in
 		${_af})
 			case $_tmpargs in
 			${_af}[[:space:]]*[0-9a-fA-F]-*)
 				ifalias_af_common_handler $_if $_af $_action \
 				`ifalias_expand_addr $_af $_action ${_tmpargs#${_af}[[:space:]]}`
 			;;
 			${_af}[[:space:]]*)
 				${IFCONFIG_CMD} $_if $_tmpargs $_action && _ret=0
 			;;
 			esac
 			_tmpargs=$_af
 		;;
 		*)
 			_tmpargs="$_tmpargs $_c"
 		;;
 		esac
 	done
 	# Process the last component if any.
 	if [ -n "${_tmpargs}" ]; then
 		case $_tmpargs in
 		${_af}[[:space:]]pass[[:space:]]*)
 			${IFCONFIG_CMD} $_if $_tmpargs $_action && _ret=0
 		;;
 		${_af}[[:space:]]*[0-9a-fA-F]-*)
 			ifalias_af_common_handler $_if $_af $_action \
 			`ifalias_expand_addr $_af $_action ${_tmpargs#${_af}[[:space:]]}`
 		;;
 		${_af}[[:space:]]*)
 			${IFCONFIG_CMD} $_if $_tmpargs $_action && _ret=0
 		;;
 		esac
 	fi
 
 	return $_ret
 }
 
 # ifalias_af_common if af action
 #	Helper function for ifalias().
 #
 ifalias_af_common()
 {
 	local _ret _if _af _action alias ifconfig_args _aliasn _c _tmpargs _iaf
 	local _vif _punct=".-/+"
 
 	_ret=1
 	_aliasn=
 	_if=$1
 	_af=$2
 	_action=$3
 
 	# Normalize $_if before using it in a pattern to list_vars()
 	ltr "$_if" "$_punct" "_" _vif
 
 	# ifconfig_IF_aliasN which starts with $_af
 	for alias in `list_vars ifconfig_${_vif}_alias[0-9]\* |
 		sort_lite -nk1.$((9+${#_vif}+7))`
 	do
 		eval ifconfig_args=\"\$$alias\"
 		_iaf=
 		case $ifconfig_args in
 		inet[[:space:]]*)	_iaf=inet ;;
 		inet6[[:space:]]*)	_iaf=inet6 ;;
 		link[[:space:]]*)	_iaf=link ;;
 		ether[[:space:]]*)	_iaf=ether ;;
 		esac
 
 		case ${_af}:${_action}:${_iaf}:"${ifconfig_args}" in
 		${_af}:*:${_af}:*)
 			_aliasn="$_aliasn $ifconfig_args"
 			;;
 		${_af}:*:"":"")
 			break
 			;;
 		inet:alias:"":*)
 			_aliasn="$_aliasn inet $ifconfig_args"
 			warn "\$${alias} needs leading" \
 			    "\"inet\" keyword for an IPv4 address."
 		esac
 	done
 
 	# backward compatibility: ipv6_ifconfig_IF_aliasN.
 	case $_af in
 	inet6)
 		for alias in `list_vars ipv6_ifconfig_${_vif}_alias[0-9]\* |
 			sort_lite -nk1.$((14+${#_vif}+7))`
 		do
 			eval ifconfig_args=\"\$$alias\"
 			case ${_action}:"${ifconfig_args}" in
 			*:"")
 				break
 			;;
 			alias:*)
 				_aliasn="${_aliasn} inet6 ${ifconfig_args}"
 				warn "\$${alias} is obsolete. " \
 				    "Use ifconfig_${_vif}_aliasN instead."
 			;;
 			esac
 		done
 	esac
 
 	# backward compatibility: ipv4_addrs_IF.
 	for _tmpargs in `get_if_var $_if ipv4_addrs_IF`; do
 		_aliasn="$_aliasn inet $_tmpargs"
 	done
 
 	# Handle ifconfig_IF_aliases, ifconfig_IF_aliasN, and the others.
 	_tmpargs=
 	for _c in `get_if_var $_if ifconfig_IF_aliases` $_aliasn; do
 		case $_c in
 		inet|inet6|link|ether)
 			case $_tmpargs in
 			${_af}[[:space:]]*)
 				eval ifalias_af_common_handler $_if $_af $_action $_tmpargs && _ret=0
 			;;
 			esac
 			_tmpargs=$_c
 		;;
 		*)
 			_tmpargs="$_tmpargs $_c"
 		esac
 	done
 	# Process the last component
 	case $_tmpargs in
 	${_af}[[:space:]]*)
 		ifalias_af_common_handler $_if $_af $_action $_tmpargs && _ret=0
 	;;
 	esac
 
 	return $_ret
 }
 
 # ipv6_prefix_hostid_addr_common if action
 #	Add or remove IPv6 prefix + hostid addr on the interface $if
 #
 ipv6_prefix_hostid_addr_common()
 {
 	local _if _action prefix j
 	_if=$1
 	_action=$2
 	prefix=`get_if_var ${_if} ipv6_prefix_IF`
 
 	if [ -n "${prefix}" ]; then
 		for j in ${prefix}; do
 			# The default prefixlen is 64.
 			plen=${j#*/}
 			case $j:$plen in
 			$plen:$j)	plen=64 ;;
 			*)		j=${j%/*} ;;
 			esac
 
 			# Normalize the last part by removing ":"
 			j=${j%::*}
 			j=${j%:}
 			${IFCONFIG_CMD} ${_if} inet6 $j:: \
 				prefixlen $plen eui64 ${_action}
 
 			# if I am a router, add subnet router
 			# anycast address (RFC 2373).
 			if checkyesno ipv6_gateway_enable; then
 				${IFCONFIG_CMD} ${_if} inet6 $j:: \
 					prefixlen $plen ${_action} anycast
 			fi
 		done
 	fi
 }
 
 # ipv6_accept_rtadv_up if
 #	Enable accepting Router Advertisement and send Router
 #	Solicitation message
 ipv6_accept_rtadv_up()
 {
 	if ipv6_autoconfif $1; then
 		${IFCONFIG_CMD} $1 inet6 accept_rtadv up
 		if [ -x /sbin/rtsol ]; then
 			/sbin/rtsol ${rtsol_flags} $1
 		fi
 		return 0
 	fi
 	return 1
 }
 
 # ipv6_accept_rtadv_down if
 #	Disable accepting Router Advertisement
 ipv6_accept_rtadv_down()
 {
 	if ipv6_autoconfif $1; then
 		${IFCONFIG_CMD} $1 inet6 -accept_rtadv
 	fi
 }
 
 # ifscript_up if
 #	Evaluate a startup script for the $if interface.
 #	It returns 0 if a script was found and processed or
 #	1 if no script was found.
 #
 ifscript_up()
 {
 	if [ -r /etc/start_if.$1 ]; then
 		. /etc/start_if.$1
 		return 0
 	else
 		return 1
 	fi
 }
 
 # ifscript_down if
 #	Evaluate a shutdown script for the $if interface.
 #	It returns 0 if a script was found and processed or
 #	1 if no script was found.
 #
 ifscript_down()
 {
 	if [ -r /etc/stop_if.$1 ]; then
 		. /etc/stop_if.$1
 		return 0
 	else
 		return 1
 	fi
 }
 
 # wlan_up
 #	Create IEEE802.11 interfaces.
 #
 wlan_up()
 {
 	local _list _iflist parent child_wlans child create_args debug_flags
 	_list=
 	_iflist=$*
 
 	# Parse wlans_$parent="$child ..."
 	for parent in `set | sed -nE 's/wlans_([a-z]+[a-z0-9]+[0-9]+)=.*/\1/p'`; do
 		child_wlans=`get_if_var $parent wlans_IF`
 		for child in ${child_wlans}; do
 			create_args="wlandev $parent `get_if_var $child create_args_IF`"
 			debug_flags="`get_if_var $child wlandebug_IF`"
 			case $_iflist in
 			""|$child|$child[[:space:]]*|*[[:space:]]$child[[:space:]]*|*[[:space:]]$child)	;;
 			*)	continue ;;
 			esac
 			# Skip if ${child} already exists.
 			if ${IFCONFIG_CMD} $child > /dev/null 2>&1; then
 				continue
 			fi
 			if expr $child : 'wlan[0-9][0-9]*$' >/dev/null 2>&1; then
 				${IFCONFIG_CMD} $child create ${create_args} && cfg=0
 			else
 				${IFCONFIG_CMD} wlan create ${create_args} name $child && cfg=0
 			fi
 			if [ $? -eq 0 ]; then
 				_list="$_list $child"
 			fi
 			if [ -n "${debug_flags}" ]; then
 				wlandebug -i $child ${debug_flags}
 			fi
 		done
 	done
 	if [ -n "${_list# }" ]; then
 		echo "Created wlan(4) interfaces: ${_list# }."
 	fi
 	debug "Created wlan(4)s: ${_list# }"
 }
 
 # wlan_down
 #	Destroy IEEE802.11 interfaces.
 #
 wlan_down()
 {
 	local _list _iflist parent child_wlans child
 	_list=
 	_iflist=$*
 
 	# Parse wlans_$parent="$child ..."
 	for parent in `set | sed -nE 's/wlans_([a-z]+[a-z0-9]+[0-9]+)=.*/\1/p'`; do
 		child_wlans=`get_if_var $parent wlans_IF`
 		for child in ${child_wlans}; do
 			case $_iflist in
 			""|$child|$child[[:space:]]*|*[[:space:]]$child[[:space:]]*|*[[:space:]]$child)	;;
 			*)	continue ;;
 			esac
 			# Skip if ${child} doesn't exists.
 			if ! ${IFCONFIG_CMD} $child > /dev/null 2>&1; then
 				continue
 			fi
 			${IFCONFIG_CMD} -n ${child} destroy
 			if [ $? -eq 0 ]; then
 				_list="$_list $child"
 			fi
 		done
 	done
 	if [ -n "${_list# }" ]; then
 		echo "Destroyed wlan(4) interfaces: ${_list# }."
 	fi
 	debug "Destroyed wlan(4)s: ${_list# }"
 }
 
 # clone_up
 #	Create cloneable interfaces.
 #
 clone_up()
 {
 	local _list ifn ifopt _iflist _inet6 _n tmpargs
 	_list=
 	_iflist=$*
 
 	# create_args_IF
 	for ifn in ${cloned_interfaces}; do
 		# Parse ifn:ifopt.
 		OIFS=$IFS; IFS=:; set -- $ifn; ifn=$1; ifopt=$2; IFS=$OIFS
 		case $_iflist in
 		""|$ifn|$ifn[[:space:]]*|*[[:space:]]$ifn[[:space:]]*|*[[:space:]]$ifn)	;;
 		*)	continue ;;
 		esac
 		case $ifn in
 		epair[0-9]*)
 			# epair(4) uses epair[0-9] for creation and
 			# epair[0-9][ab] for configuration.
 			#
 			# Skip if ${ifn}a or ${ifn}b already exist.
 			if ${IFCONFIG_CMD} ${ifn}a > /dev/null 2>&1; then
 				continue
 			elif ${IFCONFIG_CMD} ${ifn}b > /dev/null 2>&1; then
 				continue
 			fi
 			${IFCONFIG_CMD} ${ifn} create \
 			    `get_if_var ${ifn} create_args_IF`
 			if [ $? -eq 0 ]; then
 				_list="$_list ${ifn}a ${ifn}b"
 			fi
 		;;
 		*)
 			# Skip if ${ifn} already exists.
 			if ${IFCONFIG_CMD} $ifn > /dev/null 2>&1; then
 				continue
 			fi
 			${IFCONFIG_CMD} ${ifn} create \
 			    `get_if_var ${ifn} create_args_IF`
 			if [ $? -eq 0 ]; then
 				_list="$_list $ifn"
 			fi
 		esac
 	done
 	for ifn in ${gif_interfaces}; do
 		# Parse ifn:ifopt.
 		OIFS=$IFS; IFS=:; set -- $ifn; ifn=$1; ifopt=$2; IFS=$OIFS
 		case $_iflist in
 		""|$ifn|$ifn[[:space:]]*|*[[:space:]]$ifn[[:space:]]*|*[[:space:]]$ifn)	;;
 		*)	continue ;;
 		esac
 		# Skip if ifn already exists.
 		if ${IFCONFIG_CMD} $ifn > /dev/null 2>&1; then
 			continue
 		fi
 		case $ifn in
 		gif[0-9]*)
 			${IFCONFIG_CMD} $ifn create
 		;;
 		*)
 			_n=$(${IFCONFIG_CMD} gif create)
 			${IFCONFIG_CMD} $_n name $ifn
 		;;
 		esac
 		if [ $? -eq 0 ]; then
 			_list="$_list $ifn"
 			tmpargs=$(get_if_var $ifn gifconfig_IF)
 			_inet6=''
 			case "$tmpargs" in
 			'')
 			;;
 			inet6[[:space:]]*)
 				tmpargs=${tmpargs#inet6}
 				_inet6=inet6
 				# FALLTHROUGH
 			;&
 			*)
 				${IFCONFIG_CMD} $ifn $_inet6 tunnel $tmpargs
 			;;
 			esac
 		fi
 	done
 	if [ -n "${_list# }" ]; then
 		echo "Created clone interfaces: ${_list# }."
 	fi
 	debug "Cloned: ${_list# }"
 }
 
 # clone_down
 #	Destroy cloned interfaces. Destroyed interfaces are echoed to
 #	standard output.
 #
 clone_down()
 {
 	local _list ifn _difn ifopt _iflist _sticky
 	_list=
 	_iflist=$*
 
 	: ${cloned_interfaces_sticky:=NO}
 	if checkyesno cloned_interfaces_sticky; then
 		_sticky=1
 	else
 		_sticky=0
 	fi
 	for ifn in ${cloned_interfaces} ${gif_interfaces}; do
 		# Parse ifn:ifopt.
 		OIFS=$IFS; IFS=:; set -- $ifn; ifn=$1; ifopt=$2; IFS=$OIFS
 		case $ifopt:$_sticky in
 		sticky:*)	continue ;;	# :sticky => not destroy
 		nosticky:*)	;;		# :nosticky => destroy
 		*:1)		continue ;;	# global sticky knob == 1
 		esac
 		case $_iflist in
 		""|$ifn|$ifn[[:space:]]*|*[[:space:]]$ifn[[:space:]]*|*[[:space:]]$ifn)	;;
 		*)	continue ;;
 		esac
 		case $ifn in
 		epair[0-9]*)
 			# Note: epair(4) uses epair[0-9] for removal and
 			# epair[0-9][ab] for configuration.
 			#
 			# Skip if both of ${ifn}a and ${ifn}b do not exist.
 			if ${IFCONFIG_CMD} ${ifn}a > /dev/null 2>&1; then
 				_difn=${ifn}a
 			elif ${IFCONFIG_CMD} ${ifn}b > /dev/null 2>&1; then
 				_difn=${ifn}b
 			else
 				continue
 			fi
 			${IFCONFIG_CMD} -n $_difn destroy
 			if [ $? -eq 0 ]; then
 				_list="$_list ${ifn}a ${ifn}b"
 			fi
 		;;
 		*)
 			# Skip if ifn does not exist.
 			if ! ${IFCONFIG_CMD} $ifn > /dev/null 2>&1; then
 				continue
 			fi
 			${IFCONFIG_CMD} -n ${ifn} destroy
 			if [ $? -eq 0 ]; then
 				_list="$_list $ifn"
 			fi
 		;;
 		esac
 	done
 	if [ -n "${_list# }" ]; then
 		echo "Destroyed clone interfaces: ${_list# }."
 	fi
 	debug "Destroyed clones: ${_list# }"
 }
 
 # childif_create
 #	Create and configure child interfaces.  Return 0 if child
 #	interfaces are created.
 #
 childif_create()
 {
 	local cfg child child_vlans create_args debug_flags ifn i
 	cfg=1
 	ifn=$1
 
 	# Create vlan interfaces
 	child_vlans=`get_if_var $ifn vlans_IF`
 
 	if [ -n "${child_vlans}" ]; then
 		load_kld if_vlan
 	fi
 
 	for child in ${child_vlans}; do
 		if expr $child : '[1-9][0-9]*$' >/dev/null 2>&1; then
 			child="${ifn}.${child}"
 			create_args=`get_if_var $child create_args_IF`
 			${IFCONFIG_CMD} $child create ${create_args} && cfg=0
 		else
 			create_args="vlandev $ifn `get_if_var $child create_args_IF`"
 			if expr $child : 'vlan[0-9][0-9]*$' >/dev/null 2>&1; then
 				${IFCONFIG_CMD} $child create ${create_args} && cfg=0
 			else
 				i=`${IFCONFIG_CMD} vlan create ${create_args}`
 				${IFCONFIG_CMD} $i name $child && cfg=0
 			fi
 		fi
 		if autoif $child; then
 			ifn_start $child
 		fi
 	done
 
 	return ${cfg}
 }
 
 # childif_destroy
 #	Destroy child interfaces.
 #
 childif_destroy()
 {
 	local cfg child child_vlans ifn
 	cfg=1
 
 	child_vlans=`get_if_var $ifn vlans_IF`
 	for child in ${child_vlans}; do
 		if expr $child : '[1-9][0-9]*$' >/dev/null 2>&1; then
 			child="${ifn}.${child}"
 		fi
 		if ! ifexists $child; then
 			continue
 		fi
 		${IFCONFIG_CMD} -n $child destroy && cfg=0
 	done
 
 	return ${cfg}
 }
 
 # ng_mkpeer
 #	Create netgraph nodes.
 #
 ng_mkpeer()
 {
 	ngctl -f - 2> /dev/null <<EOF
 mkpeer $*
 msg dummy nodeinfo
 EOF
 }
 
 # ng_create_one
 #	Create netgraph nodes.
 #
 ng_create_one()
 {
 	local t
 
 	ng_mkpeer $* | while read line; do
 		t=`expr "${line}" : '.* name="\([a-z]*[0-9]*\)" .*'`
 		if [ -n "${t}" ]; then
 			echo ${t}
 			return
 		fi
 	done
 }
 
 # ifnet_rename [ifname]
 #	Rename interfaces if ifconfig_IF_name is defined.
 #
 ifnet_rename()
 {
 	local _if _ifname
 
 	# ifconfig_IF_name
 	for _if in ${*:-$(${IFCONFIG_CMD} -l)}; do
 		_ifname=`get_if_var $_if ifconfig_IF_name`
 		if [ ! -z "$_ifname" ]; then
 			${IFCONFIG_CMD} $_if name $_ifname
 		fi
 	done
 
 	return 0
 }
 
 # list_net_interfaces type
 #	List all network interfaces. The type of interface returned
 #	can be controlled by the type argument. The type
 #	argument can be any of the following:
 #		nodhcp	- all interfaces, excluding DHCP configured interfaces
 #		dhcp	- list only DHCP configured interfaces
 #		noautoconf	- all interfaces, excluding IPv6 Stateless
 #				  Address Autoconf configured interfaces
 #		autoconf	- list only IPv6 Stateless Address Autoconf
 #				  configured interfaces
 #	If no argument is specified all network interfaces are output.
 #	Note that the list will include cloned interfaces if applicable.
 #	Cloned interfaces must already exist to have a chance to appear
 #	in the list if ${network_interfaces} is set to `auto'.
 #
 list_net_interfaces()
 {
 	local type _tmplist _list _autolist _lo _if
 	type=$1
 
 	# Get a list of ALL the interfaces and make lo0 first if it's there.
 	#
 	_tmplist=
 	case ${network_interfaces} in
 	[Aa][Uu][Tt][Oo])
 		_autolist="`${IFCONFIG_CMD} -l`"
 		_lo=
 		for _if in ${_autolist} ; do
 			if autoif $_if; then
 				if [ "$_if" = "lo0" ]; then
 					_lo="lo0 "
 				else
 					_tmplist="${_tmplist} ${_if}"
 				fi
 			fi
 		done
 		_tmplist="${_lo}${_tmplist# }"
 	;;
 	*)
 		for _if in ${network_interfaces} ${cloned_interfaces}; do
 			# epair(4) uses epair[0-9] for creation and
 			# epair[0-9][ab] for configuration.
 			case $_if in
 			epair[0-9]*)
 				_tmplist="$_tmplist ${_if}a ${_if}b"
 			;;
 			*)
 				_tmplist="$_tmplist $_if"
 			;;
 			esac
 		done
 		#
 		# lo0 is effectively mandatory, so help prevent foot-shooting
 		#
 		case "$_tmplist" in
 		lo0|'lo0 '*|*' lo0'|*' lo0 '*)
 			# This is fine, do nothing
 			_tmplist="${_tmplist# }"
 		;;
 		*)
 			_tmplist="lo0 ${_tmplist# }"
 		;;
 		esac
 	;;
 	esac
 
 	_list=
 	case "$type" in
 	nodhcp)
 		for _if in ${_tmplist} ; do
 			if ! dhcpif $_if && \
 			   [ -n "`_ifconfig_getargs $_if`" ]; then
 				_list="${_list# } ${_if}"
 			fi
 		done
 	;;
 	dhcp)
 		for _if in ${_tmplist} ; do
 			if dhcpif $_if; then
 				_list="${_list# } ${_if}"
 			fi
 		done
 	;;
 	noautoconf)
 		for _if in ${_tmplist} ; do
 			if ! ipv6_autoconfif $_if && \
 			   [ -n "`_ifconfig_getargs $_if ipv6`" ]; then
 				_list="${_list# } ${_if}"
 			fi
 		done
 	;;
 	autoconf)
 		for _if in ${_tmplist} ; do
 			if ipv6_autoconfif $_if; then
 				_list="${_list# } ${_if}"
 			fi
 		done
 	;;
 	*)
 		_list=${_tmplist}
 	;;
 	esac
 
 	echo $_list
 
 	return 0
 }
 
 # get_default_if -address_family
 #	Get the interface of the default route for the given address family.
 #	The -address_family argument must be suitable passing to route(8).
 #
 get_default_if()
 {
 	local routeget oldifs defif line
 	defif=
 	oldifs="$IFS"
 	IFS="
 "
 	for line in `route -n get $1 default 2>/dev/null`; do
 		case $line in
 		*interface:*)
 			defif=${line##*: }
 			;;
 		esac
 	done
 	IFS=${oldifs}
 
 	echo $defif
 }
 
 # hexdigit arg
 #	Echo decimal number $arg (single digit) in hexadecimal format.
 hexdigit()
 {
 	printf '%x\n' "$1"
 }
 
 # hexprint arg
 #	Echo decimal number $arg (multiple digits) in hexadecimal format.
 hexprint()
 {
 	printf '%x\n' "$1"
 }
 
 is_wired_interface()
 {
 	local media
 
 	case `${IFCONFIG_CMD} $1 2>/dev/null` in
 	*media:?Ethernet*) media=Ethernet ;;
 	esac
 
 	test "$media" = "Ethernet"
 }
 
 # network6_getladdr if [flag]
 #	Echo link-local address from $if if any.
 #	If flag is defined, tentative ones will be excluded.
 network6_getladdr()
 {
 	local _if _flag proto addr rest
 	_if=$1
 	_flag=$2
 
 	${IFCONFIG_CMD} $_if inet6 2>/dev/null | while read proto addr rest; do
 		case "${proto}/${addr}/${_flag}/${rest}" in
 		inet6/fe80::*//*)
 			echo ${addr}
 		;;
 		inet6/fe80:://*tentative*)	# w/o flag
 			sleep `${SYSCTL_N} net.inet6.ip6.dad_count`
 			network6_getladdr $_if $_flags
 		;;
 		inet6/fe80::/*/*tentative*)	# w/ flag
 			echo ${addr}
 		;;
 		*)
 			continue
 		;;
 		esac
 
 		return
 	done
 }