freebsd-dev/etc/network.subr

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#
# 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.
#
1999-08-27 23:37:10 +00:00
# $FreeBSD$
#
#
# Subroutines commonly used from network startup scripts.
# Requires that rc.conf be loaded first.
#
# 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()
{
_cfg=1
ifconfig_args=`ifconfig_getargs $1`
if [ -n "${ifconfig_args}" ]; then
ifconfig $1 up
ifconfig $1 ${ifconfig_args}
_cfg=0
fi
if wpaif $1; then
/etc/rc.d/wpa_supplicant start $1
_cfg=0 # XXX: not sure this should count
fi
if dhcpif $1; then
if [ $_cfg -ne 0 ] ; then
ifconfig $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()
{
[ -z "$1" ] && return 1
_cfg=1
if wpaif $1; then
/etc/rc.d/wpa_supplicant stop $1
_cfg=0
fi
if dhcpif $1; then
/etc/rc.d/dhclient stop $1
_cfg=0
fi
if ifexists $1; then
ifconfig $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()
{
if [ $# -ne 2 -a $# -ne 3 ]; then
err 3 'USAGE: get_if_var name var [default]'
fi
_if=$1
_punct=". - / +"
for _punct_c in $_punct; do
_if=`ltr ${_if} ${_punct_c} '_'`
done
_var=$2
_default=$3
prefix=${_var%%IF*}
suffix=${_var##*IF}
eval echo \${${prefix}${_if}${suffix}-${_default}}
}
# _ifconfig_getargs if
# Echos the arguments for the supplied interface to stdout.
# returns 1 if empty. In general, ifconfig_getargs should be used
# outside this file.
_ifconfig_getargs()
{
_ifn=$1
if [ -z "$_ifn" ]; then
return 1
fi
get_if_var $_ifn ifconfig_IF "$ifconfig_DEFAULT"
}
# ifconfig_getargs if
# Takes the result from _ifconfig_getargs and removes pseudo
# args such as DHCP and WPA.
ifconfig_getargs()
{
_tmpargs=`_ifconfig_getargs $1`
if [ $? -eq 1 ]; then
return 1
fi
_args=
for _arg in $_tmpargs; do
case $_arg in
[Dd][Hh][Cc][Pp]) ;;
[Nn][Oo][Aa][Uu][Tt][Oo]) ;;
[Nn][Oo][Ss][Yy][Nn][Cc][Dd][Hh][Cc][Pp]) ;;
[Ss][Yy][Nn][Cc][Dd][Hh][Cc][Pp]) ;;
[Ww][Pp][Aa]) ;;
*)
_args="$_args $_arg"
;;
esac
done
echo $_args
}
# autoif
# Returns 0 if the interface should be automaticly configured at
# boot time and 1 otherwise.
autoif()
{
_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()
{
_tmpargs=`_ifconfig_getargs $1`
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()
{
_tmpargs=`_ifconfig_getargs $1`
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
if checkyesno synchronous_dhclient; then
return 0
else
return 1
fi
}
# wpaif if
# Returns 0 if the interface is a WPA interface and 1 otherwise.
wpaif()
{
_tmpargs=`_ifconfig_getargs $1`
for _arg in $_tmpargs; do
case $_arg in
[Ww][Pp][Aa])
return 0
;;
esac
done
return 1
}
# ipv6if if
# Returns 0 if the interface should be configured for IPv6 and
# 1 otherwise.
ipv6if()
{
if ! checkyesno ipv6_enable; then
return 1
fi
case "${ipv6_network_interfaces}" in
[Aa][Uu][Tt][Oo])
return 0
;;
''|[Nn][Oo][Nn][Ee])
return 1
;;
esac
for v6if in ${ipv6_network_interfaces}; do
if [ "${v6if}" = "${1}" ]; then
return 0
fi
done
return 1
}
# ifexists if
# Returns 0 if the interface exists and 1 otherwise.
ifexists()
{
ifconfig -n $1 > /dev/null 2>&1
}
# ipv4_up if
# add IPv4 addresses to the interface $if
ipv4_up()
{
_if=$1
ifalias_up ${_if}
ipv4_addrs_common ${_if} alias
}
# ipv4_down if
# remove IPv4 addresses from the interface $if
ipv4_down()
{
_if=$1
_ifs="^"
_ret=1
ifexists ${_if} || return 1
inetList="`ifconfig ${_if} | grep 'inet ' | tr "\n" "$_ifs"`"
oldifs="$IFS"
IFS="$_ifs"
for _inet in $inetList ; do
# get rid of extraneous line
[ -z "$_inet" ] && break
_inet=`expr "$_inet" : '.*\(inet \([0-9]\{1,3\}\.\)\{3\}[0-9]\{1,3\}\).*'`
IFS="$oldifs"
ifconfig ${_if} ${_inet} delete
IFS="$_ifs"
_ret=0
done
IFS="$oldifs"
ifalias_down ${_if} && _ret=0
ipv4_addrs_common ${_if} -alias && _ret=0
return $_ret
}
# ipv4_addrs_common if action
# Evaluate the ifconfig_if_ipv4 arguments for interface $if
# and use $action to add or remove IPv4 addresses from $if.
ipv4_addrs_common()
{
_ret=1
_if=$1
_action=$2
# get ipv4-addresses
cidr_addr=`get_if_var $_if ipv4_addrs_IF`
for _cidr in ${cidr_addr}; do
_ipaddr=${_cidr%%/*}
_netmask="/"${_cidr##*/}
_range=${_ipaddr##*.}
_ipnet=${_ipaddr%.*}
_iplow=${_range%-*}
_iphigh=${_range#*-}
# clear netmask when removing aliases
if [ "${_action}" = "-alias" ]; then
_netmask=""
fi
_ipcount=${_iplow}
while [ "${_ipcount}" -le "${_iphigh}" ]; do
eval "ifconfig ${_if} ${_action} ${_ipnet}.${_ipcount}${_netmask}"
_ipcount=$((${_ipcount}+1))
_ret=0
# only the first ipaddr in a subnet need the real netmask
if [ "${_action}" != "-alias" ]; then
_netmask="/32"
fi
done
done
return $_ret
}
# ifalias_up if
# Configure aliases for network interface $if.
# It returns 0 if at least one alias was configured or
# 1 if there were none.
#
ifalias_up()
{
_ret=1
alias=0
while : ; do
ifconfig_args=`get_if_var $1 ifconfig_IF_alias${alias}`
if [ -n "${ifconfig_args}" ]; then
ifconfig $1 ${ifconfig_args} alias
alias=$((${alias} + 1))
_ret=0
else
break
fi
done
return $_ret
}
#ifalias_down if
# Remove aliases for network interface $if.
# It returns 0 if at least one alias was removed or
# 1 if there were none.
#
ifalias_down()
{
_ret=1
alias=0
while : ; do
ifconfig_args=`get_if_var $1 ifconfig_IF_alias${alias}`
if [ -n "${ifconfig_args}" ]; then
ifconfig $1 ${ifconfig_args} -alias
alias=$((${alias} + 1))
_ret=0
else
break
fi
done
return $_ret
}
# 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
fi
return 1
}
# 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
fi
return 1
}
# Create cloneable interfaces.
#
clone_up()
{
_prefix=
_list=
for ifn in ${cloned_interfaces}; do
ifconfig ${ifn} create
if [ $? -eq 0 ]; then
_list="${_list}${_prefix}${ifn}"
[ -z "$_prefix" ] && _prefix=' '
fi
done
debug "Cloned: ${_list}"
}
# Destroy cloned interfaces. Destroyed interfaces are echoed
# to standard output.
#
clone_down()
{
_prefix=
_list=
for ifn in ${cloned_interfaces}; do
ifconfig ${ifn} destroy
if [ $? -eq 0 ]; then
_list="${_list}${_prefix}${ifn}"
[ -z "$_prefix" ] && _prefix=' '
fi
done
debug "Destroyed clones: ${_list}"
}
# Create netgraph nodes.
#
ng_mkpeer() {
ngctl -f - 2> /dev/null <<EOF
mkpeer $*
msg dummy nodeinfo
EOF
}
ng_create_one() {
ng_mkpeer $* | while read line; do
t=`expr "${line}" : '.* name="\([a-z]*[0-9]*\)" .*'`
if [ -n "${t}" ]; then
echo ${t}
return
fi
done
}
gif_up() {
for i in ${gif_interfaces}; do
peers=`get_if_var $i gifconfig_IF`
case ${peers} in
'')
continue
;;
*)
if expr $i : 'gif[0-9][0-9]*$' >/dev/null 2>&1; then
ifconfig $i create >/dev/null 2>&1
else
gif=`ifconfig gif create`
ifconfig $gif name $i
fi
ifconfig $i tunnel ${peers}
ifconfig $i up
;;
esac
done
}
# ng_fec_create ifn
# Configure Fast EtherChannel for interface $ifn. Returns 0 if FEC
# arguments were found and configured; returns !0 otherwise.
ng_fec_create() {
local req_iface iface bogus
req_iface="$1"
ngctl shutdown ${req_iface}: > /dev/null 2>&1
bogus=""
while true; do
iface=`ng_create_one fec dummy fec`
if [ -z "${iface}" ]; then
exit 2
fi
if [ "${iface}" = "${req_iface}" ]; then
break
fi
bogus="${bogus} ${iface}"
done
for iface in ${bogus}; do
ngctl shutdown ${iface}:
done
}
fec_up() {
for i in ${fec_interfaces}; do
ng_fec_create $i
for j in `get_if_var $i fecconfig_IF`; do
case ${j} in
'')
continue
;;
*)
ngctl msg ${i}: add_iface "\"${j}\""
;;
esac
done
done
}
#
# ipx_up ifn
# Configure any IPX addresses for interface $ifn. Returns 0 if IPX
# arguments were found and configured; returns 1 otherwise.
#
ipx_up()
{
ifn="$1"
ifconfig_args=`get_if_var $ifn ifconfig_IF_ipx`
if [ -n "${ifconfig_args}" ]; then
ifconfig ${ifn} ${ifconfig_args}
return 0
fi
return 1
}
# ipx_down ifn
# Remove IPX addresses for interface $ifn. Returns 0 if IPX
# addresses were found and unconfigured. It returns 1, otherwise.
#
ipx_down()
{
[ -z "$1" ] && return 1
_ifs="^"
_ret=1
ifexists $1 || return 1
ipxList="`ifconfig $1 | grep 'ipx ' | tr "\n" "$_ifs"`"
oldifs="$IFS"
IFS="$_ifs"
for _ipx in $ipxList ; do
# get rid of extraneous line
[ -z "$_ipx" ] && break
_ipx=`expr "$_ipx" : '.*\(ipx [0-9a-h]\{1,8\}H*\.[0-9a-h]\{1,12\}\).*'`
IFS="$oldifs"
ifconfig $1 ${_ipx} delete
IFS="$_ifs"
_ret=0
done
IFS="$oldifs"
return $_ret
}
# ifnet_rename
# Rename all requested interfaces.
#
ifnet_rename()
{
_ifn_list="`ifconfig -l`"
[ -z "$_ifn_list" ] && return 0
for _if in ${_ifn_list} ; do
_ifname=`get_if_var $_if ifconfig_IF_name`
if [ ! -z "$_ifname" ]; then
ifconfig $_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
# 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()
{
type=$1
# Get a list of ALL the interfaces and make lo0 first if it's there.
#
case ${network_interfaces} in
[Aa][Uu][Tt][Oo])
_prefix=''
_autolist="`ifconfig -l`"
_lo=
for _if in ${_autolist} ; do
if autoif $_if; then
if [ "$_if" = "lo0" ]; then
_lo="lo0 "
else
_tmplist="${_tmplist}${_prefix}${_if}"
[ -z "$_prefix" ] && _prefix=' '
fi
fi
done
_tmplist="${_lo}${_tmplist}"
;;
*)
_tmplist="${network_interfaces} ${cloned_interfaces}"
;;
esac
if [ -z "$type" ]; then
echo $_tmplist
return 0
fi
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# Separate out dhcp and non-dhcp interfaces
#
_aprefix=
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_bprefix=
for _if in ${_tmplist} ; do
if dhcpif $_if; then
_dhcplist="${_dhcplist}${_aprefix}${_if}"
[ -z "$_aprefix" ] && _aprefix=' '
elif [ -n "`_ifconfig_getargs $_if`" ]; then
_nodhcplist="${_nodhcplist}${_bprefix}${_if}"
[ -z "$_bprefix" ] && _bprefix=' '
fi
done
case "$type" in
nodhcp)
echo $_nodhcplist
;;
dhcp)
echo $_dhcplist
;;
esac
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return 0
}
hexdigit()
{
if [ $1 -lt 10 ]; then
echo $1
else
case $1 in
10) echo a ;;
11) echo b ;;
12) echo c ;;
13) echo d ;;
14) echo e ;;
15) echo f ;;
esac
fi
}
hexprint()
{
val=$1
str=''
dig=`hexdigit $((${val} & 15))`
str=${dig}${str}
val=$((${val} >> 4))
while [ ${val} -gt 0 ]; do
dig=`hexdigit $((${val} & 15))`
str=${dig}${str}
val=$((${val} >> 4))
done
echo ${str}
}
# Setup the interfaces for IPv6
network6_interface_setup()
{
interfaces=$*
rtsol_interfaces=''
case ${ipv6_gateway_enable} in
[Yy][Ee][Ss])
rtsol_available=no
;;
*)
rtsol_available=yes
;;
esac
for i in $interfaces; do
rtsol_interface=yes
prefix=`get_if_var $i ipv6_prefix_IF`
if [ -n "${prefix}" ]; then
rtsol_available=no
rtsol_interface=no
laddr=`network6_getladdr $i`
hostid=`expr "${laddr}" : 'fe80::\(.*\)%\(.*\)'`
for j in ${prefix}; do
address=$j\:${hostid}
ifconfig $i inet6 ${address} prefixlen 64 alias
case ${ipv6_gateway_enable} in
[Yy][Ee][Ss])
# subnet-router anycast address
# (rfc2373)
ifconfig $i inet6 $j:: prefixlen 64 \
alias anycast
;;
esac
done
fi
ipv6_ifconfig=`get_if_var $i ipv6_ifconfig_IF`
if [ -n "${ipv6_ifconfig}" ]; then
rtsol_available=no
rtsol_interface=no
ifconfig $i inet6 ${ipv6_ifconfig} alias
fi
if [ ${rtsol_available} = yes -a ${rtsol_interface} = yes ]
then
case ${i} in
lo0|gif[0-9]*|stf[0-9]*|faith[0-9]*|lp[0-9]*|sl[0-9]*|tun[0-9]*|pflog[0-9]*|pfsync[0-9]*)
;;
*)
rtsol_interfaces="${rtsol_interfaces} ${i}"
;;
esac
else
ifconfig $i inet6
fi
done
if [ ${rtsol_available} = yes -a -n "${rtsol_interfaces}" ]; then
# Act as endhost - automatically configured.
# You can configure only single interface, as
# specification assumes that autoconfigured host has
# single interface only.
sysctl net.inet6.ip6.accept_rtadv=1
set ${rtsol_interfaces}
ifconfig $1 up
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rtsol ${rtsol_flags} $1
fi
for i in $interfaces; do
alias=0
while : ; do
ipv6_ifconfig=`get_if_var $i ipv6_ifconfig_IF_alias${alias}`
if [ -z "${ipv6_ifconfig}" ]; then
break;
fi
ifconfig $i inet6 ${ipv6_ifconfig} alias
alias=$((${alias} + 1))
done
done
}
# Setup IPv6 to IPv4 mapping
network6_stf_setup()
{
case ${stf_interface_ipv4addr} in
[Nn][Oo] | '')
;;
*)
# assign IPv6 addr and interface route for 6to4 interface
stf_prefixlen=$((16+${stf_interface_ipv4plen:-0}))
OIFS="$IFS"
IFS=".$IFS"
set ${stf_interface_ipv4addr}
IFS="$OIFS"
hexfrag1=`hexprint $(($1*256 + $2))`
hexfrag2=`hexprint $(($3*256 + $4))`
ipv4_in_hexformat="${hexfrag1}:${hexfrag2}"
case ${stf_interface_ipv6_ifid} in
[Aa][Uu][Tt][Oo] | '')
for i in ${ipv6_network_interfaces}; do
laddr=`network6_getladdr ${i}`
case ${laddr} in
'')
;;
*)
break
;;
esac
done
stf_interface_ipv6_ifid=`expr "${laddr}" : \
'fe80::\(.*\)%\(.*\)'`
case ${stf_interface_ipv6_ifid} in
'')
stf_interface_ipv6_ifid=0:0:0:1
;;
esac
;;
esac
ifconfig stf0 create >/dev/null 2>&1
ifconfig stf0 inet6 2002:${ipv4_in_hexformat}:${stf_interface_ipv6_slaid:-0}:${stf_interface_ipv6_ifid} \
prefixlen ${stf_prefixlen}
# disallow packets to malicious 6to4 prefix
route add -inet6 2002:e000:: -prefixlen 20 ::1 -reject
route add -inet6 2002:7f00:: -prefixlen 24 ::1 -reject
route add -inet6 2002:0000:: -prefixlen 24 ::1 -reject
route add -inet6 2002:ff00:: -prefixlen 24 ::1 -reject
;;
esac
}
# Setup static routes
network6_static_routes_setup()
{
# Set up any static routes.
case ${ipv6_defaultrouter} in
[Nn][Oo] | '')
;;
*)
ipv6_static_routes="default ${ipv6_static_routes}"
ipv6_route_default="default ${ipv6_defaultrouter}"
;;
esac
case ${ipv6_static_routes} in
[Nn][Oo] | '')
;;
*)
for i in ${ipv6_static_routes}; do
ipv6_route_args=`get_if_var $i ipv6_route_IF`
route add -inet6 ${ipv6_route_args}
done
;;
esac
}
# Setup faith
network6_faith_setup()
{
case ${ipv6_faith_prefix} in
[Nn][Oo] | '')
;;
*)
sysctl net.inet6.ip6.keepfaith=1
ifconfig faith0 create >/dev/null 2>&1
ifconfig faith0 up
for prefix in ${ipv6_faith_prefix}; do
prefixlen=`expr "${prefix}" : ".*/\(.*\)"`
case ${prefixlen} in
'')
prefixlen=96
;;
*)
prefix=`expr "${prefix}" : \
"\(.*\)/${prefixlen}"`
;;
esac
route add -inet6 ${prefix} -prefixlen ${prefixlen} ::1
route change -inet6 ${prefix} -prefixlen ${prefixlen} \
-ifp faith0
done
;;
esac
}
# Install the "default interface" to kernel, which will be used
# as the default route when there's no router.
network6_default_interface_setup()
{
# Choose IPv6 default interface if it is not clearly specified.
case ${ipv6_default_interface} in
'')
for i in ${ipv6_network_interfaces}; do
case $i in
lo0|faith[0-9]*)
continue
;;
esac
laddr=`network6_getladdr $i exclude_tentative`
case ${laddr} in
'')
;;
*)
ipv6_default_interface=$i
break
;;
esac
done
;;
esac
# Disallow unicast packets without outgoing scope identifiers,
# or route such packets to a "default" interface, if it is specified.
route add -inet6 fe80:: -prefixlen 10 ::1 -reject
case ${ipv6_default_interface} in
[Nn][Oo] | '')
route add -inet6 ff02:: -prefixlen 16 ::1 -reject
;;
*)
laddr=`network6_getladdr ${ipv6_default_interface}`
route add -inet6 ff02:: ${laddr} -prefixlen 16 -interface \
-cloning
# Disable installing the default interface with the
# case net.inet6.ip6.forwarding=0 and
# net.inet6.ip6.accept_rtadv=0, due to avoid conflict
# between the default router list and the manual
# configured default route.
case ${ipv6_gateway_enable} in
[Yy][Ee][Ss])
;;
*)
if [ `sysctl -n net.inet6.ip6.accept_rtadv` -eq 1 ]
then
ndp -I ${ipv6_default_interface}
fi
;;
esac
;;
esac
}
network6_getladdr()
{
ifconfig $1 2>/dev/null | while read proto addr rest; do
case ${proto} in
inet6)
case ${addr} in
fe80::*)
if [ -z "$2" ]; then
echo ${addr}
return
fi
case ${rest} in
*tentative*)
continue
;;
*)
echo ${addr}
return
esac
esac
esac
done
}