#
# 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.
#
# $FreeBSD: src/etc/network.subr,v 1.163 2005/06/30 04:52:47 brooks Exp $
#

#
# Subroutines commonly used from network startup scripts.
# Requires that /etc/rc.subr 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()
{
	local _cfg ifconfig_args
	_cfg=1

	ifconfig_args=`ifconfig_getargs $1`
	if [ -n "${ifconfig_args}" ]; then
		ifconfig $1 ${ifconfig_args}
		ifconfig $1 up
		_cfg=0
	fi

	if wpaif $1; then
		ifconfig $1 up
		/etc/rc.d/wpa_supplicant start $1
		# NOTE: wpa_supplicant(8) needs to control the interface's
		#	state in order to perform the SSID scan.  But
		#	dhcpcd(8), which may be started by the "dhcp_client"
		#	below, can race against wpa_supplicant(8) and modify
		#	the interface's state, breaking the SSID scan and
		#	preventing the SSID association.
		#	Insert a small delay here to workaround the issue.
		sleep 1
		_cfg=0		# XXX: not sure this should count
	fi

	if dhcpif $1; then
		/etc/rc.d/dhcp_client start $1
		_cfg=0
	fi

	return $_cfg
}

# ifconfig_down if
#	Remove all inet entries from the $if interface. It returns
#	0 if inet entries were found and removed. It returns 1 if
#	no entries were found or they could not be removed.
#
ifconfig_down()
{
	local _cfg _ifs oldifs _inet inetList

	[ -z "$1" ] && return 1
	_ifs="^"
	_cfg=1

	inetList="`ifconfig $1 | grep 'inet ' | tr "\n" "$_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 $1 ${_inet} delete
		IFS="$_ifs"
		_cfg=0
	done
	IFS="$oldifs"

	if wpaif $1; then
		/etc/rc.d/wpa_supplicant stop $1
	fi

	if dhcpif $1; then
		/etc/rc.d/dhcp_client 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()
{
	local _if _punct_c _punct _var _default prefix suffix

	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 [af]
#	Echos the arguments for the supplied interface to stdout.
#	Returns 1 if no interface is specified.
#	In general, the ifconfig_getargs() below should be used outside
#	this file.
#
_ifconfig_getargs()
{
	local _if _ifn _af _args

	_ifn=$1
	_af=${2:+${2}_}

	if [ -z "$_ifn" ]; then
		return 1
	fi

	_args=`get_if_var $_ifn ${_af}ifconfig_IF`
	if [ -z "$_args" -a -n "${pccard_ifconfig}" ]; then
		for _if in ${removable_interfaces} ; do
			if [ "$_if" = "$_ifn" ] ; then
				_args=${pccard_ifconfig}
				break
			fi
		done
	fi

	echo $_args
}

# 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 is_optarg

	_tmpargs=`_ifconfig_getargs $1 $2`
	if [ $? -eq 1 ]; then
		return 1
	fi
	_args=

	is_optarg=no
	for _arg in $_tmpargs; do
		if [ "$is_optarg" = "no" ]; then
			case $_arg in
			[Dd][Hh][Cc][Pp])
				;;
			[Ww][Pp][Aa])
				;;
			*)
				_args="$_args $_arg"
				case $_arg in
				authmode)
					is_optarg=yes
					;;
				esac
				;;
			esac
		else
			_args="$_args $_arg"
			is_optarg=no
		fi
	done

	echo $_args
}

# ipv6if if
#	Returns 0 if the interface should be configured for IPv6 and
#	1 otherwise.
#
ipv6if()
{
	local _if _tmpargs
	_if=$1

	# lo0 is always IPv6-enabled
	if [ "$_if" = "lo0" ]; then
		return 0
	fi

	case ${ipv6_enable} in
	[Nn][Oo]|[Ff][Aa][Ll][Ss][Ee]|[Oo][Ff][Ff]|0)
		return 1
		;;
	esac

	case "${ipv6_network_interfaces}" in
	$_if|"$_if "*|*" $_if"|*" $_if "*|[Aa][Uu][Tt][Oo])
		# True if $ipv6_ifconfig_IF 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

		;;
	esac

	return 1
}

# dhcpif if [ipv4|ipv6]
#	Returns 0 if the interface needs DHCP for IPv4/IPv6 and 1 otherwise.
#	If the second argument is "ipv4" (or "ipv6"), then only IPv4 (or
#	IPv6) is checked, otherwise both are checked.
#
dhcpif()
{
	local _tmpargs _arg _if _af
	_if=$1
	_af=$2

	if [ -z "$_af" -o "$_af" = "ipv4" ]; then
		_tmpargs=`_ifconfig_getargs $_if`
		for _arg in $_tmpargs; do
			case $_arg in
			[Dd][Hh][Cc][Pp])
				return 0
				;;
			esac
		done
	fi

	if [ -z "$_af" -o "$_af" = "ipv6" ] && ipv6if $_if; then
		_tmpargs=`_ifconfig_getargs $_if ipv6`
		for _arg in $_tmpargs; do
			case $_arg in
			[Dd][Hh][Cc][Pp])
				return 0
				;;
			esac
		done
	fi

	return 1
}

# wpaif if
#	Returns 0 if the interface is a WPA interface and 1 otherwise.
#
wpaif()
{
	local _tmpargs _arg is_optarg

	_tmpargs=`_ifconfig_getargs $1`
	is_optarg=no
	for _arg in $_tmpargs; do
		if [ "$is_optarg" = "no" ]; then
			case $_arg in
			[Ww][Pp][Aa])
				return 0
				;;
			authmode)
				is_optarg=yes
				;;
			esac
		else
			is_optarg=no
		fi
	done

	return 1
}

# ifexists if
#	Returns 0 if the interface exists and 1 otherwise.
#
ifexists()
{
	[ -z "$1" ] && return 1
	ifconfig -n $1 >/dev/null 2>&1
}

# ifalias_common if action [ipv6]
#	Helper function for ifalias_up() and ifalias_down().
#	The $action argument can be either "alias" (to add an
#	alias) or "-alias" (to remove an alias).
#	Returns 0 if at least one alias was added/removed or
#	1 if there were none.
#
ifalias_common()
{
	local _if _action _af _af2 _ret _var _args _alias
	_if=$1
	_action=$2
	_af=$3

	_ret=1
	_alias=0
	while : ; do
		if [ "${_af}" = "ipv6" ]; then
			_af2="inet6"
			_var="ipv6_ifconfig_IF_alias${_alias}"
		else
			_af2="inet"
			_var="ifconfig_IF_alias${_alias}"
		fi
		_args=`get_if_var $_if $_var`
		_args="${_args#${_af2} }"
		if [ -z "${_args}" ]; then
			break
		fi
		ifconfig $_if $_af2 $_args $_action
		_alias=$((${_alias} + 1))
		_ret=0
	done
	return $_ret
}

# ifalias_up if [ipv6]
#	Configure IPv4 aliases for network interface $if or
#	IPv6 aliases if the second argument is "ipv6".
#	It returns 0 if at least one alias was configured or
#	1 if there were none.
#
ifalias_up()
{
	ifalias_common $1 alias $2
}

# ifalias_down if [ipv6]
#	Remove IPv4 aliases for network interface $if or
#	IPv6 aliases if the second argument is "ipv6".
#	It returns 0 if at least one alias was removed or
#	1 if there were none.
#
ifalias_down()
{
	ifalias_common $1 -alias $2
}

# 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
}

# wlan_up
#	Create IEEE 802.11 interfaces.
#
wlan_up()
{
	local _prefix _list parent child child_wlans create_args debug_flags
	_prefix=
	_list=

	for parent in `${SYSCTL_N} -q net.wlan.devices`; do
		# Parse wlans_$parent="$child ..."
		child_wlans=`get_if_var $parent wlans_IF`
		for child in ${child_wlans}; do
			if ifexists $child; then
				continue
			fi

			create_args="wlandev $parent `get_if_var $child create_args_IF`"
			debug_flags="`get_if_var $child wlandebug_IF`"
			if expr $child : 'wlan[0-9][0-9]*$' >/dev/null 2>&1; then
				ifconfig $child create ${create_args}
			else
				ifconfig wlan create ${create_args} name $child
			fi
			if [ $? -eq 0 ]; then
				_list="${_list}${_prefix}${child}"
				[ -z "$_prefix" ] && _prefix=' '
			fi
			if [ -n "${debug_flags}" ]; then
				wlandebug -i $child ${debug_flags}
			fi
		done
	done

	if [ -n "${_list}" ]; then
		echo "Created wlan interfaces: ${_list}"
	fi
	debug "Created wlan interfaces: ${_list}"
}

# wlan_down
#	Destroy IEEE 802.11 interfaces.
#
wlan_down()
{
	local _prefix _list parent child child_wlans
	_prefix=
	_list=

	for parent in `${SYSCTL_N} -q net.wlan.devices`; do
		child_wlans=`get_if_var $parent wlans_IF`
		for child in ${child_wlans}; do
			if ! ifexists $child; then
				continue
			fi

			ifconfig -n $child destroy
			if [ $? -eq 0 ]; then
				_list="${_list}${_prefix}${child}"
				[ -z "$_prefix" ] && _prefix=' '
			fi
		done
	done

	if [ -n "${_list}" ]; then
		echo "Destroyed wlan interfaces: ${_list}"
	fi
	debug "Destroyed wlan interfaces: ${_list}"
}

# clone_up
#	Create cloneable interfaces.
#
clone_up()
{
	local _prefix _list ifn
	_prefix=
	_list=

	for ifn in ${cloned_interfaces}; do
		ifconfig ${ifn} create
		if [ $? -eq 0 ]; then
			_list="${_list}${_prefix}${ifn}"
			[ -z "$_prefix" ] && _prefix=' '
		fi
	done
	if [ -n "${_list}" ]; then
		echo "Created clone interfaces: ${_list}"
	fi
	debug "Created clone interfaces: ${_list}"
}

# clone_down
#	Destroy cloned interfaces.
#
clone_down()
{
	local _prefix _list ifn
	_prefix=
	_list=

	for ifn in ${cloned_interfaces}; do
		ifconfig ${ifn} destroy
		if [ $? -eq 0 ]; then
			_list="${_list}${_prefix}${ifn}"
			[ -z "$_prefix" ] && _prefix=' '
		fi
	done
	if [ -n "${_list}" ]; then
		echo "Destroyed clone interfaces: ${_list}"
	fi
	debug "Destroyed clone interfaces: ${_list}"
}

# gif_up
#	Create IPv6<-->IPv4 tunnels
#
gif_up() {
	local _if _peers

	case ${gif_interfaces} in
	[Nn][Oo] | '')
		return
		;;
	esac

	for _if in ${gif_interfaces}; do
		eval _peers=\$gifconfig_${_if}
		case ${_peers} in
		'')
			continue
			;;
		*)
			ifconfig $_if create >/dev/null 2>&1
			ifconfig $_if tunnel ${_peers}
			ifconfig $_if up
			;;
		esac
	done
}

# ifnet_rename
#	Rename all requested interfaces.
#
ifnet_rename()
{
	local _ifn_list _if _ifname

	_ifn_list=$(ifconfig -l)
	[ -z "$_ifn_list" ] && return 0

	for _if in ${_ifn_list} ; do
		_ifname=`get_if_var $_if ifconfig_IF_name`
		if [ -n "$_ifname" ]; then
			ifconfig $_if name $_ifname
		fi
	done
	return 0
}

# list_net_interfaces
#	List all network interfaces.
#	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 _tmplist _autolist _lo _if

	case ${network_interfaces} in
	[Aa][Uu][Tt][Oo])
		_autolist=$(ifconfig -l)
		_lo=
		for _if in ${_autolist} ; do
			if [ "$_if" = "lo0" ]; then
				_lo="lo0"
			else
				_tmplist="${_tmplist} ${_if}"
			fi
		done
		_tmplist="${_lo} ${_tmplist}"
		;;
	*)
		_tmplist="${network_interfaces} ${cloned_interfaces}"
		;;
	esac

	echo $_tmplist
}

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()
{
	local val str dig
	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}
}


#
# IPv6-specific setup subroutines
#

# Setup the interfaces for IPv6
network6_interface_setup()
{
	local interfaces rtsol_interfaces ipv6_ifconfig
	local rtsol_available rtsol_interface
	local prefix laddr hostid address
	local _if j

	interfaces=$*
	rtsol_interfaces=''
	case ${ipv6_gateway_enable} in
	[Yy][Ee][Ss])
		rtsol_available=no
		;;
	*)
		rtsol_available=yes
		;;
	esac
	for _if in $interfaces; do
		rtsol_interface=yes
		prefix=`get_if_var $_if ipv6_prefix_IF`
		if [ -n "${prefix}" ]; then
			rtsol_available=no
			rtsol_interface=no
			laddr=`network6_getladdr $_if`
			hostid=`expr "${laddr}" : 'fe80::\(.*\)%\(.*\)'`
			for j in ${prefix}; do
				address=$j\:${hostid}
				ifconfig $_if inet6 ${address} prefixlen 64 alias

				case ${ipv6_gateway_enable} in
				[Yy][Ee][Ss])
					# subnet-router anycast address
					# (rfc2373)
					ifconfig $_if inet6 $j:: prefixlen 64 \
						alias anycast
					;;
				esac
			done
		fi
		ipv6_ifconfig=`ifconfig_getargs $_if ipv6`
		ipv6_ifconfig="${ipv6_ifconfig#inet6 }"
		if [ -n "${ipv6_ifconfig}" ]; then
			rtsol_available=no
			rtsol_interface=no
			ifconfig $_if inet6 ${ipv6_ifconfig} alias
		fi

		if [ "${rtsol_available}" = "yes" -a \
		     "${rtsol_interface}" = "yes" ]; then
			case ${i} in
			lo0|gif[0-9]*|stf[0-9]*|lp[0-9]*|sl[0-9]*|tun[0-9]*)
				;;
			*)
				rtsol_interfaces="${rtsol_interfaces} ${_if}"
				;;
			esac
		else
			ifconfig $_if 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_W} net.inet6.ip6.accept_rtadv=1
		set ${rtsol_interfaces}
		ifconfig $1 up
		echo "Auto configuring interface $1 ..."
		rtsol $1
	fi

	for _if in $interfaces; do
		ifalias_up $_if ipv6
	done
}

# Setup IPv6 to IPv4 mapping
network6_stf_setup()
{
	local stf_prefixlen stf_interface_ipv6_ifid
	local hexfrag1 hexfrag2 ipv4_in_hexformat laddr
	local _if OIFS

	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 _if in ${ipv6_network_interfaces}; do
				laddr=`network6_getladdr $_if`
				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()
{
	local _rt

	# 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 _rt in ${ipv6_static_routes}; do
			eval ipv6_route_args=\$ipv6_route_${_rt}
			route add -inet6 ${ipv6_route_args}
		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()
{
	local _if laddr

	# Choose IPv6 default interface if it is not clearly specified.
	case ${ipv6_default_interface} in
	'')
		for _if in ${ipv6_network_interfaces}; do
			if [ "${_if}" = "lo0" ]; then
				continue
			fi

			laddr=`network6_getladdr $_if exclude_tentative`
			case ${laddr} in
			'')
				;;
			*)
				ipv6_default_interface=$_if
				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()
{
	local proto addr rest

	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
}