iptables: Remove package

[people/amarx/ipfire-3.x.git] / firewall / src / functions.ip

#!/bin/bash
###############################################################################
#                                                                             #
# IPFire.org - A linux based firewall                                         #
# Copyright (C) 2009  Michael Tremer & Christian Schmidt                      #
#                                                                             #
# This program is free software: you can redistribute it and/or modify        #
# it under the terms of the GNU General Public License as published by        #
# the Free Software Foundation, either version 3 of the License, or           #
# (at your option) any later version.                                         #
#                                                                             #
# This program is distributed in the hope that it will be useful,             #
# but WITHOUT ANY WARRANTY; without even the implied warranty of              #
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the               #
# GNU General Public License for more details.                                #
#                                                                             #
# You should have received a copy of the GNU General Public License           #
# along with this program.  If not, see <http://www.gnu.org/licenses/>.       #
#                                                                             #
###############################################################################

###############################################################################
# General IP address manipulation functions
#     ip_encode - Encodes an IP to an integer
#                 Parameters: ip address (e.g. 192.168.0.1)
#                 Returns   : integer
#     ip_decode - Decodes an integer to an IP
#                 Parameters: integer
#                 Returns   : ip address
#     ip_valid - Checks if given IP is valid
#                 Parameters: IP
#                 Returns   : boolean
#
# General subnet functions
#     ip_range - Enumerates members of an IP range
#                 Parameters: ip range (e.g. 192.168.0.1-192.168.0.128)
#                 Returns   : several subnets/IPs
#     ip_range_explicit - Enumerates ALL IP addresses of an IP range
#                 Parameters: ip range
#                 Returns   : several IPs
#     subnet_network - Calculates the network address of a CIDR
#                 Parameters: CIDR network (e.g. 192.168.0.0/24)
#                 Returns   : Network address
#     subnet_broadcast - Calculates the broadcast address of a CIDR
#                 Parameters: CIDR network
#                 Returns   : Broadcast address
#     ip_in_subnet - Checks if an IP is in given subnet
#                 Parameters: IP address, subnet
#                 Returns   : Boolean
#     mask_to_cidr - Converts a subnet mask to cidr type
#                 Parameters: subnet (e.g. 255.255.255.0)
#                 Returns   : CIDR (e.g. 24)
#

function ip_encode() {
	IFS=$(ifs .)

	local int=0
	for field in $1; do
		int=$(( $(( $int << 8 )) | $field ))
	done

	echo $int
	IFS=$(ifs)
}

function ip_decode() {
	addr=$1

	local x
	local y

	y=$(($addr & 255))
	for x in 1 2 3; do
		addr=$(($addr >> 8))
		y=$(($addr & 255)).$y
	done

	echo $y
}

function ip_range() {
	local first
	local last
	local l
	local x
	local y
	local z
	local vlsm

	case "$1" in
		!*)
			echo $1
			return
			;;
		[0-9]*.*.*.*-*.*.*.*)
			;;
		*)
			echo $1
			return
			;;
	esac

	first=$(ip_encode ${1%-*})
	last=$(ip_encode ${1#*-})

	if [ $first -gt $last ]; then
		error "Invalid IP address range: $1"
	fi

	l=$(( $last + 1 ))

	while [ $l -gt $first ]; do
		vlsm=
		x=31
		y=2
		z=1

		while [ $(( $first % $y )) -eq 0 ] && [ $l -gt $(( $first + $y )) ]; do
			vlsm=/$x
			x=$(( $x - 1 ))
			z=$y
			y=$(( $y * 2 ))
		done
	
		echo $(ip_decode $first)$vlsm
		first=$(($first + $z))
	done
}

function ip_range_explicit() {
	local first
	local last

	case $1 in
		[0-9]*.*.*.*-*.*.*.*)
			;;
		*)
			echo $1
			return
			;;
	esac

	first=$(ip_encode ${1%-*})
	last=$(ip_encode ${1#*-})

	if [ $first -gt $last ]; then
		error "Invalid IP address range: $1"
	fi

	while ! [ $first -gt $last ]; do
		echo $(ip_decode $first)
		first=$(($first + 1))
	done
}

function _netmask() {
	local vlsm
	vlsm=${1#*/}
	[ $vlsm -eq 0 ] && echo 0 || echo $(( -1 << $(( 32 - $vlsm )) ))
}

function subnet_network() {
	local encodedaddr
	encodedaddr=$(ip_encode ${1%/*})
	local netmask
	netmask=$(_netmask $1)

	echo $(ip_decode $(($encodedaddr & $netmask)))
}

function _broadcast() {
	local x
	x=$(( 32 - ${1#*/} ))
	[ $x -eq 32 ] && echo -1 || echo $(( $(( 1 << $x )) - 1 ))
}

function subnet_broadcast() {
	local encodedaddr
	encodedaddr=$(ip_encode ${1%/*})
	local netmask
	netmask=$(_netmask $1)
	local broadcast
	broadcast=$(_broadcast $1)

	echo $(ip_decode $(( $(($encodedaddr & $netmask)) | $broadcast )))
}

function ip_in_subnet() {
	local netmask
	netmask=$(_netmask $2)
	[ $(( $(ip_encode $1) & $netmask)) = $(( $(ip_encode ${2%/*}) & $netmask )) ]
}

function mask_to_cidr() {
	local mask
	mask=$(ip_encode $1)
	local cidr
	cidr=0
	local x
	x=$(( 128 << 24 )) # 0x80000000

	while [ $(( $x & $mask )) -ne 0 ]; do
		[ $mask -eq $x ] && mask=0 || mask=$(( $mask << 1 ))
		cidr=$(($cidr + 1))
	done

	if [ $(( $mask & 2147483647 )) -ne 0 ]; then # 2147483647 = 0x7fffffff
		echo "Invalid net mask: $1" >&2
	else
		echo $cidr
	fi
}

function ip_valid() {
	local x
	IFS=$(ifs .)
	for x in $1; do
		case $x in
			[0-9]|[0-9][0-9]|[1-2][0-9][0-9])
				[ $x -lt 256 ] || { IFS=$(ifs); return 1; }
				;;
			*)
				IFS=$(ifs)
				return 1
				;;
		esac
	done
	IFS=$(ifs)
	return 0
}