mirror of
https://gitlab.com/shorewall/code.git
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567b2f37f9
git-svn-id: https://shorewall.svn.sourceforge.net/svnroot/shorewall/trunk@5374 fbd18981-670d-0410-9b5c-8dc0c1a9a2bb
1419 lines
31 KiB
Bash
1419 lines
31 KiB
Bash
#!/bin/sh
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#
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# Shorewall 3.4 -- /usr/share/shorewall/lib.base
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#
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# This program is under GPL [http://www.gnu.org/copyleft/gpl.htm]
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#
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# (c) 1999,2000,2001,2002,2003,2004,2005,2006,2007 - Tom Eastep (teastep@shorewall.net)
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#
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# Complete documentation is available at http://shorewall.net
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#
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# This program is free software; you can redistribute it and/or modify
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# it under the terms of Version 2 of the GNU General Public License
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# as published by the Free Software Foundation.
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#
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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# GNU General Public License for more details.
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#
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# You should have received a copy of the GNU General Public License
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# along with this program; if not, write to the Free Software
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# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA
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#
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# This library contains the code common to all Shorewall components. It is copied into
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# the compiled script with the -e compiler flag is specified and is loaded by
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# /sbin/shorewall, /usr/share/shorewall/compiler and /usr/share/shorewall/firewall. It
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# is also released as part of Shorewall Lite where it is used by /sbin/shorewall-lite
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# and /usr/share/shorewall-lite/shorecap.
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#
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SHOREWALL_LIBVERSION=30303
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[ -n "${VARDIR:=/var/lib/shorewall}" ]
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[ -n "${SHAREDIR:=/usr/share/shorewall}" ]
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[ -n "${CONFDIR:=/etc/shorewall}" ]
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#
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# Message to stderr
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#
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error_message() # $* = Error Message
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{
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echo " $@" >&2
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}
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#
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# Conditionally produce message
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#
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progress_message() # $* = Message
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{
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local timestamp=
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if [ $VERBOSE -gt 1 ]; then
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[ -n "$TIMESTAMP" ] && timestamp="$(date +%H:%M:%S) "
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echo "${timestamp}$@"
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fi
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}
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progress_message2() # $* = Message
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{
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local timestamp=
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if [ $VERBOSE -gt 0 ]; then
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[ -n "$TIMESTAMP" ] && timestamp="$(date +%H:%M:%S) "
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echo "${timestamp}$@"
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fi
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}
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progress_message3() # $* = Message
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{
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local timestamp=
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if [ $VERBOSE -ge 0 ]; then
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[ -n "$TIMESTAMP" ] && timestamp="$(date +%H:%M:%S) "
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echo "${timestamp}$@"
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fi
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}
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#
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# Split a colon-separated list into a space-separated list
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#
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split() {
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local ifs=$IFS
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IFS=:
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echo $*
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IFS=$ifs
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}
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#
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# Search a list looking for a match -- returns zero if a match found
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# 1 otherwise
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#
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list_search() # $1 = element to search for , $2-$n = list
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{
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local e=$1
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while [ $# -gt 1 ]; do
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shift
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[ "x$e" = "x$1" ] && return 0
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done
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return 1
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}
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#
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# Suppress all output for a command
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#
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qt()
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{
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"$@" >/dev/null 2>&1
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}
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#
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# Determine if Shorewall is "running"
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#
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shorewall_is_started() {
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qt $IPTABLES -L shorewall -n
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}
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#
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# Echos the fully-qualified name of the calling shell program
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#
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my_pathname() {
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cd $(dirname $0)
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echo $PWD/$(basename $0)
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}
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#
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# Source a user exit file if it exists
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#
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run_user_exit() # $1 = file name
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{
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local user_exit=$(find_file $1)
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if [ -f $user_exit ]; then
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progress_message "Processing $user_exit ..."
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. $user_exit
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fi
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}
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#
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# Set a standard chain's policy
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#
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setpolicy() # $1 = name of chain, $2 = policy
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{
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run_iptables -P $1 $2
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}
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#
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# Set a standard chain to enable established and related connections
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#
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setcontinue() # $1 = name of chain
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{
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run_iptables -A $1 -m state --state ESTABLISHED,RELATED -j ACCEPT
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}
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#
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# Flush one of the NAT table chains
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#
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flushnat() # $1 = name of chain
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{
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run_iptables -t nat -F $1
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}
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#
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# Flush one of the Mangle table chains
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#
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flushmangle() # $1 = name of chain
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{
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run_iptables -t mangle -F $1
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}
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#
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# Flush and delete all user-defined chains in the filter table
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#
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deleteallchains() {
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run_iptables -F
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run_iptables -X
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}
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#
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# Load a Kernel Module -- assumes that the variable 'moduledirectories' contains
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# a space-separated list of directories to search for
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# the module and that 'moduleloader' contains the
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# module loader command.
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#
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loadmodule() # $1 = module name, $2 - * arguments
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{
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local modulename=$1
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local modulefile
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local suffix
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if ! list_search $modulename $MODULES ; then
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shift
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for suffix in $MODULE_SUFFIX ; do
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for directory in $moduledirectories; do
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modulefile=$directory/${modulename}.${suffix}
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if [ -f $modulefile ]; then
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case $moduleloader in
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insmod)
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insmod $modulefile $*
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;;
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*)
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modprobe $modulename $*
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;;
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esac
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break 2
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fi
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done
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done
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fi
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}
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#
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# Reload the Modules
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#
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reload_kernel_modules() {
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local save_modules_dir=$MODULESDIR
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local directory
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local moduledirectories=
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local moduleloader=modprobe
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if ! qt mywhich modprobe; then
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moduleloader=insmod
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fi
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[ -z "$MODULESDIR" ] && MODULESDIR=/lib/modules/$(uname -r)/kernel/net/ipv4/netfilter:/lib/modules/$(uname -r)/kernel/net/netfilter
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MODULES=$(lsmod | cut -d ' ' -f1)
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for directory in $(split $MODULESDIR); do
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[ -d $directory ] && moduledirectories="$moduledirectories $directory"
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done
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[ -n "$moduledirectories" ] && while read command; do
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eval $command
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done
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MODULESDIR=$save_modules_dir
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}
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#
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# Load kernel modules required for Shorewall
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#
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load_kernel_modules() # $1 = Yes, if we are to save moduleinfo in $VARDIR
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{
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local save_modules_dir=$MODULESDIR
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local directory
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local moduledirectories=
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local moduleloader=modprobe
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local savemoduleinfo=${1:-Yes} # So old compiled scripts still work
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if ! qt mywhich modprobe; then
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moduleloader=insmod
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fi
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[ -z "$MODULESDIR" ] && \
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MODULESDIR=/lib/modules/$(uname -r)/kernel/net/ipv4/netfilter:/lib/modules/$(uname -r)/kernel/net/netfilter
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for directory in $(split $MODULESDIR); do
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[ -d $directory ] && moduledirectories="$moduledirectories $directory"
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done
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modules=$(find_file modules)
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if [ -f $modules -a -n "$moduledirectories" ]; then
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MODULES=$(lsmod | cut -d ' ' -f1)
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progress_message "Loading Modules..."
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. $modules
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if [ $savemoduleinfo = Yes ]; then
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[ -d ${VARDIR} ] || mkdir -p ${VARDIR}
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echo MODULESDIR="$MODULESDIR" > ${VARDIR}/.modulesdir
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cp -f $modules ${VARDIR}/.modules
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fi
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elif [ $savemoduleinfo = Yes ]; then
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[ -d ${VARDIR} ] || mkdir -p ${VARDIR}
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> ${VARDIR}/.modulesdir
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> ${VARDIR}/.modules
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fi
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MODULESDIR=$save_modules_dir
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}
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#
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# Call this function to assert mutual exclusion with Shorewall. If you invoke the
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# /sbin/shorewall program while holding mutual exclusion, you should pass "nolock" as
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# the first argument. Example "shorewall nolock refresh"
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#
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# This function uses the lockfile utility from procmail if it exists.
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# Otherwise, it uses a somewhat race-prone algorithm to attempt to simulate the
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# behavior of lockfile.
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#
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mutex_on()
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{
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local try=0
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local lockf=${VARDIR}/lock
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MUTEX_TIMEOUT=${MUTEX_TIMEOUT:-60}
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if [ $MUTEX_TIMEOUT -gt 0 ]; then
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[ -d ${VARDIR} ] || mkdir -p ${VARDIR}
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if qt mywhich lockfile; then
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lockfile -${MUTEX_TIMEOUT} -r1 ${lockf}
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else
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while [ -f ${lockf} -a ${try} -lt ${MUTEX_TIMEOUT} ] ; do
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sleep 1
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try=$((${try} + 1))
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done
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if [ ${try} -lt ${MUTEX_TIMEOUT} ] ; then
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# Create the lockfile
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echo $$ > ${lockf}
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else
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echo "Giving up on lock file ${lockf}" >&2
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fi
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fi
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fi
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}
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#
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# Call this function to release mutual exclusion
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#
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mutex_off()
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{
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rm -f ${VARDIR}/lock
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}
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#
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# Load an optional library
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#
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lib_load() # $1 = Name of the Library, $2 = Error Message heading if the library cannot be found
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{
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local lib=${SHAREDIR}/lib.$1
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local loaded
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eval loaded=\$LIB_${1}_LOADED
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if [ -z "$loaded" ]; then
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if [ -f $lib ]; then
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progress_message "Loading library $lib..."
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. $lib
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eval LIB_${1}_LOADED=Yes
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else
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startup_error "$2 requires the Shorewall library $1 ($lib) which is not installed"
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fi
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fi
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}
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#
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# Determine if an optional library is available
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#
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lib_avail() # $1 = Name of the Library
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{
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[ -f ${SHAREDIR}/lib.$1 ]
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}
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#
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# Note: The following set of IP address manipulation functions have anomalous
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# behavior when the shell only supports 32-bit signed arithmatic and
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# the IP address is 128.0.0.0 or 128.0.0.1.
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#
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LEFTSHIFT='<<'
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#
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# Validate an IP address
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#
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valid_address() {
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local x y
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local ifs=$IFS
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IFS=.
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for x in $1; do
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case $x in
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[0-9]|[0-9][0-9]|[1-2][0-9][0-9])
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[ $x -lt 256 ] || { IFS=$ifs; return 2; }
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;;
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*)
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IFS=$ifs
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return 2
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;;
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esac
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done
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IFS=$ifs
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return 0
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}
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#
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# Convert an IP address in dot quad format to an integer
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#
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decodeaddr() {
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local x
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local temp=0
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local ifs=$IFS
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IFS=.
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for x in $1; do
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temp=$(( $(( $temp $LEFTSHIFT 8 )) | $x ))
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done
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echo $temp
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IFS=$ifs
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}
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#
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# convert an integer to dot quad format
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#
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encodeaddr() {
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addr=$1
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local x
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local y=$(($addr & 255))
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for x in 1 2 3 ; do
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addr=$(($addr >> 8))
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y=$(($addr & 255)).$y
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done
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echo $y
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}
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#
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# Enumerate the members of an IP range -- When using a shell supporting only
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# 32-bit signed arithmetic, the range cannot span 128.0.0.0.
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#
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# Comes in two flavors:
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#
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# ip_range() - produces a mimimal list of network/host addresses that spans
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# the range.
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#
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# ip_range_explicit() - explicitly enumerates the range.
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#
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ip_range() {
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local first last l x y z vlsm
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case $1 in
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!*)
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#
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# Let iptables complain if it's a range
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#
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echo $1
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return
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;;
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[0-9]*.*.*.*-*.*.*.*)
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;;
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*)
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echo $1
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return
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;;
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esac
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first=$(decodeaddr ${1%-*})
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last=$(decodeaddr ${1#*-})
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if [ $first -gt $last ]; then
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fatal_error "Invalid IP address range: $1"
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fi
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l=$(( $last + 1 ))
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while [ $first -le $last ]; do
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vlsm=
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x=31
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y=2
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z=1
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while [ $(( $first % $y )) -eq 0 -a $(( $first + $y )) -le $l ]; do
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vlsm=/$x
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x=$(( $x - 1 ))
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z=$y
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y=$(( $y * 2 ))
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done
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echo $(encodeaddr $first)$vlsm
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first=$(($first + $z))
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done
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}
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ip_range_explicit() {
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local first last
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case $1 in
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[0-9]*.*.*.*-*.*.*.*)
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;;
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*)
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echo $1
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return
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;;
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esac
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first=$(decodeaddr ${1%-*})
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last=$(decodeaddr ${1#*-})
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if [ $first -gt $last ]; then
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fatal_error "Invalid IP address range: $1"
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fi
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while [ $first -le $last ]; do
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echo $(encodeaddr $first)
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first=$(($first + 1))
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done
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}
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#
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# Netmask from CIDR
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#
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ip_netmask() {
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local vlsm=${1#*/}
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[ $vlsm -eq 0 ] && echo 0 || echo $(( -1 $LEFTSHIFT $(( 32 - $vlsm )) ))
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}
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#
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# Network address from CIDR
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#
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ip_network() {
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local decodedaddr=$(decodeaddr ${1%/*})
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local netmask=$(ip_netmask $1)
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echo $(encodeaddr $(($decodedaddr & $netmask)))
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}
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#
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# The following hack is supplied to compensate for the fact that many of
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# the popular light-weight Bourne shell derivatives don't support XOR ("^").
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#
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ip_broadcast() {
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local x=$(( 32 - ${1#*/} ))
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[ $x -eq 32 ] && echo -1 || echo $(( $(( 1 $LEFTSHIFT $x )) - 1 ))
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}
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#
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# Calculate broadcast address from CIDR
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#
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broadcastaddress() {
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local decodedaddr=$(decodeaddr ${1%/*})
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local netmask=$(ip_netmask $1)
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local broadcast=$(ip_broadcast $1)
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echo $(encodeaddr $(( $(($decodedaddr & $netmask)) | $broadcast )))
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}
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#
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# Test for network membership
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#
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in_network() # $1 = IP address, $2 = CIDR network
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{
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local netmask=$(ip_netmask $2)
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test $(( $(decodeaddr $1) & $netmask)) -eq $(( $(decodeaddr ${2%/*}) & $netmask ))
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}
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#
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# Netmask to VLSM
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#
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ip_vlsm() {
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local mask=$(decodeaddr $1)
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local vlsm=0
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local x=$(( 128 << 24 )) # 0x80000000
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while [ $(( $x & $mask )) -ne 0 ]; do
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[ $mask -eq $x ] && mask=0 || mask=$(( $mask $LEFTSHIFT 1 )) # Not all shells shift 0x80000000 left properly.
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vlsm=$(($vlsm + 1))
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done
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if [ $(( $mask & 2147483647 )) -ne 0 ]; then # 2147483647 = 0x7fffffff
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echo "Invalid net mask: $1" >&2
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else
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echo $vlsm
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fi
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}
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|
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#
|
|
# Chain name base for an interface -- replace all periods with underscores in the passed name.
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|
# The result is echoed (less trailing "+").
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#
|
|
chain_base() #$1 = interface
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|
{
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local c=${1%%+}
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|
|
while true; do
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case $c in
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@*)
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c=at_${c#@}
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;;
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|
*.*)
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c="${c%.*}_${c##*.}"
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;;
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*-*)
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c="${c%-*}_${c##*-}"
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|
;;
|
|
*%*)
|
|
c="${c%\%*}_${c##*%}"
|
|
;;
|
|
*@*)
|
|
c="${c%@*}_${c##*@}"
|
|
;;
|
|
*)
|
|
echo ${c:=common}
|
|
return
|
|
;;
|
|
esac
|
|
done
|
|
}
|
|
|
|
#
|
|
# Query NetFilter about the existence of a filter chain
|
|
#
|
|
chain_exists() # $1 = chain name
|
|
{
|
|
qt $IPTABLES -L $1 -n
|
|
}
|
|
|
|
#
|
|
# Find the value 'dev' in the passed arguments then echo the next value
|
|
#
|
|
|
|
find_device() {
|
|
while [ $# -gt 1 ]; do
|
|
[ "x$1" = xdev ] && echo $2 && return
|
|
shift
|
|
done
|
|
}
|
|
|
|
#
|
|
# Find the value 'via' in the passed arguments then echo the next value
|
|
#
|
|
|
|
find_gateway() {
|
|
while [ $# -gt 1 ]; do
|
|
[ "x$1" = xvia ] && echo $2 && return
|
|
shift
|
|
done
|
|
}
|
|
|
|
#
|
|
# Find the value 'mtu' in the passed arguments then echo the next value
|
|
#
|
|
|
|
find_mtu() {
|
|
while [ $# -gt 1 ]; do
|
|
[ "x$1" = xmtu ] && echo $2 && return
|
|
shift
|
|
done
|
|
}
|
|
|
|
#
|
|
# Find the value 'peer' in the passed arguments then echo the next value up to
|
|
# "/"
|
|
#
|
|
|
|
find_peer() {
|
|
while [ $# -gt 1 ]; do
|
|
[ "x$1" = xpeer ] && echo ${2%/*} && return
|
|
shift
|
|
done
|
|
}
|
|
|
|
#
|
|
# Find the interfaces that have a route to the passed address - the default
|
|
# route is not used.
|
|
#
|
|
|
|
find_rt_interface() {
|
|
ip route ls | while read addr rest; do
|
|
case $addr in
|
|
*/*)
|
|
in_network ${1%/*} $addr && echo $(find_device $rest)
|
|
;;
|
|
default)
|
|
;;
|
|
*)
|
|
if [ "$addr" = "$1" -o "$addr/32" = "$1" ]; then
|
|
echo $(find_device $rest)
|
|
fi
|
|
;;
|
|
esac
|
|
done
|
|
}
|
|
|
|
#
|
|
# Try to find the gateway through an interface looking for 'nexthop'
|
|
|
|
find_nexthop() # $1 = interface
|
|
{
|
|
echo $(find_gateway `ip route ls | grep "[[:space:]]nexthop.* $1"`)
|
|
}
|
|
|
|
#
|
|
# Find the default route's interface
|
|
#
|
|
find_default_interface() {
|
|
ip route ls | while read first rest; do
|
|
[ "$first" = default ] && echo $(find_device $rest) && return
|
|
done
|
|
}
|
|
|
|
#
|
|
# Echo the name of the interface(s) that will be used to send to the
|
|
# passed address
|
|
#
|
|
|
|
find_interface_by_address() {
|
|
local dev="$(find_rt_interface $1)"
|
|
local first rest
|
|
|
|
[ -z "$dev" ] && dev=$(find_default_interface)
|
|
|
|
[ -n "$dev" ] && echo $dev
|
|
}
|
|
|
|
#
|
|
# Find the interface with the passed MAC address
|
|
#
|
|
|
|
find_interface_by_mac() {
|
|
local mac=$1 first second rest dev
|
|
|
|
ip link ls | while read first second rest; do
|
|
case $first in
|
|
*:)
|
|
dev=$second
|
|
;;
|
|
*)
|
|
if [ "$second" = $mac ]; then
|
|
echo ${dev%:}
|
|
return
|
|
fi
|
|
esac
|
|
done
|
|
}
|
|
|
|
#
|
|
# Determine if Interface is up
|
|
#
|
|
interface_is_up() {
|
|
[ -n "$(ip link ls dev $1 | grep -e '[<,]UP[,>]')" ]
|
|
}
|
|
|
|
#
|
|
# Find interface address--returns the first IP address assigned to the passed
|
|
# device
|
|
#
|
|
find_first_interface_address() # $1 = interface
|
|
{
|
|
#
|
|
# get the line of output containing the first IP address
|
|
#
|
|
addr=$(ip -f inet addr show $1 2> /dev/null | grep 'inet .* global' | head -n1)
|
|
#
|
|
# If there wasn't one, bail out now
|
|
#
|
|
[ -n "$addr" ] || fatal_error "Can't determine the IP address of $1"
|
|
#
|
|
# Strip off the trailing VLSM mask (or the peer IP in case of a P-t-P link)
|
|
# along with everything else on the line
|
|
#
|
|
echo $addr | sed 's/\s*inet //;s/\/.*//;s/ peer.*//'
|
|
}
|
|
|
|
find_first_interface_address_if_any() # $1 = interface
|
|
{
|
|
#
|
|
# get the line of output containing the first IP address
|
|
#
|
|
addr=$(ip -f inet addr show $1 2> /dev/null | grep 'inet .* global' | head -n1)
|
|
#
|
|
# Strip off the trailing VLSM mask (or the peer IP in case of a P-t-P link)
|
|
# along with everything else on the line
|
|
#
|
|
[ -n "$addr" ] && echo $addr | sed 's/\s*inet //;s/\/.*//;s/ peer.*//' || echo 0.0.0.0
|
|
}
|
|
|
|
#
|
|
# Determine if interface is usable from a Netfilter prespective
|
|
#
|
|
interface_is_usable() # $1 = interface
|
|
{
|
|
interface_is_up $1 && [ "$(find_first_interface_address_if_any $1)" != 0.0.0.0 ]
|
|
}
|
|
|
|
#
|
|
# Find interface addresses--returns the set of addresses assigned to the passed
|
|
# device
|
|
#
|
|
find_interface_addresses() # $1 = interface
|
|
{
|
|
ip -f inet addr show $1 | grep inet\ | sed 's/\s*inet //;s/\/.*//;s/ peer.*//'
|
|
}
|
|
|
|
#
|
|
# echo the list of networks routed out of a given interface
|
|
#
|
|
get_routed_networks() # $1 = interface name, $2-n = Fatal error message
|
|
{
|
|
local address
|
|
local rest
|
|
|
|
ip route show dev $1 2> /dev/null |
|
|
while read address rest; do
|
|
if [ "x$address" = xdefault ]; then
|
|
if [ $# -gt 1 ]; then
|
|
shift
|
|
fatal_error "$@"
|
|
else
|
|
"WARNING: default route ignored on interface $1"
|
|
fi
|
|
else
|
|
[ "$address" = "${address%/*}" ] && address="${address}/32"
|
|
echo $address
|
|
fi
|
|
done
|
|
}
|
|
|
|
#
|
|
# Internal version of 'which'
|
|
#
|
|
mywhich() {
|
|
local dir
|
|
|
|
for dir in $(split $PATH); do
|
|
if [ -x $dir/$1 ]; then
|
|
echo $dir/$1
|
|
return 0
|
|
fi
|
|
done
|
|
|
|
return 2
|
|
}
|
|
|
|
#
|
|
# Set default config path
|
|
#
|
|
ensure_config_path() {
|
|
local F=${SHAREDIR}/configpath
|
|
if [ -z "$CONFIG_PATH" ]; then
|
|
[ -f $F ] || { echo " ERROR: $F does not exist"; exit 2; }
|
|
. $F
|
|
fi
|
|
|
|
if [ -n "$SHOREWALL_DIR" ]; then
|
|
[ "${CONFIG_PATH%%:*}" = "$SHOREWALL_DIR" ] || CONFIG_PATH=$SHOREWALL_DIR:$CONFIG_PATH
|
|
fi
|
|
}
|
|
|
|
#
|
|
# Find a File -- For relative file name, look in each ${CONFIG_PATH} then ${CONFDIR}
|
|
#
|
|
find_file()
|
|
{
|
|
local saveifs= directory
|
|
|
|
case $1 in
|
|
/*)
|
|
echo $1
|
|
;;
|
|
*)
|
|
for directory in $(split $CONFIG_PATH); do
|
|
if [ -f $directory/$1 ]; then
|
|
echo $directory/$1
|
|
return
|
|
fi
|
|
done
|
|
|
|
echo ${CONFDIR}/$1
|
|
;;
|
|
esac
|
|
}
|
|
|
|
#
|
|
# Get fully-qualified name of file
|
|
#
|
|
resolve_file() # $1 = file name
|
|
{
|
|
local pwd=$PWD
|
|
|
|
case $1 in
|
|
/*)
|
|
echo $1
|
|
;;
|
|
.)
|
|
echo $pwd
|
|
;;
|
|
./*)
|
|
echo ${pwd}${1#.}
|
|
;;
|
|
..)
|
|
cd ..
|
|
echo $PWD
|
|
cd $pwd
|
|
;;
|
|
../*)
|
|
cd ..
|
|
resolve_file ${1#../}
|
|
cd $pwd
|
|
;;
|
|
*)
|
|
echo $pwd/$1
|
|
;;
|
|
esac
|
|
}
|
|
|
|
#
|
|
# Perform variable substitution on the passed argument and echo the result
|
|
#
|
|
expand() # $@ = contents of variable which may be the name of another variable
|
|
{
|
|
eval echo \"$@\"
|
|
}
|
|
|
|
#
|
|
# Function for including one file into another
|
|
#
|
|
INCLUDE() {
|
|
. $(find_file $(expand $@))
|
|
}
|
|
|
|
#
|
|
# Set the Shorewall state
|
|
#
|
|
set_state () # $1 = state
|
|
{
|
|
echo "$1 ($(date))" > ${VARDIR}/state
|
|
}
|
|
|
|
#
|
|
# Determine which optional facilities are supported by iptables/netfilter
|
|
#
|
|
determine_capabilities() {
|
|
qt $IPTABLES -t nat -L -n && NAT_ENABLED=Yes || NAT_ENABLED=
|
|
qt $IPTABLES -t mangle -L -n && MANGLE_ENABLED=Yes || MANGLE_ENABLED=
|
|
|
|
CONNTRACK_MATCH=
|
|
MULTIPORT=
|
|
XMULTIPORT=
|
|
POLICY_MATCH=
|
|
PHYSDEV_MATCH=
|
|
IPRANGE_MATCH=
|
|
RECENT_MATCH=
|
|
OWNER_MATCH=
|
|
IPSET_MATCH=
|
|
CONNMARK=
|
|
XCONNMARK=
|
|
CONNMARK_MATCH=
|
|
XCONNMARK_MATCH=
|
|
RAW_TABLE=
|
|
IPP2P_MATCH=
|
|
LENGTH_MATCH=
|
|
CLASSIFY_TARGET=
|
|
ENHANCED_REJECT=
|
|
USEPKTTYPE=
|
|
KLUDGEFREE=
|
|
MARK=
|
|
XMARK=
|
|
MANGLE_FORWARD=
|
|
COMMENTS=
|
|
|
|
qt $IPTABLES -N fooX1234
|
|
qt $IPTABLES -A fooX1234 -m conntrack --ctorigdst 192.168.1.1 -j ACCEPT && CONNTRACK_MATCH=Yes
|
|
qt $IPTABLES -A fooX1234 -p tcp -m multiport --dports 21,22 -j ACCEPT && MULTIPORT=Yes
|
|
qt $IPTABLES -A fooX1234 -p tcp -m multiport --dports 21:22 -j ACCEPT && XMULTIPORT=Yes
|
|
qt $IPTABLES -A fooX1234 -m policy --pol ipsec --mode tunnel --dir in -j ACCEPT && POLICY_MATCH=Yes
|
|
|
|
if qt $IPTABLES -A fooX1234 -m physdev --physdev-in eth0 -j ACCEPT; then
|
|
PHYSDEV_MATCH=Yes
|
|
fi
|
|
|
|
if qt $IPTABLES -A fooX1234 -m iprange --src-range 192.168.1.5-192.168.1.124 -j ACCEPT; then
|
|
IPRANGE_MATCH=Yes
|
|
if [ -z "${KLUDGEFREE}" ]; then
|
|
qt $IPTABLES -A fooX1234 -m iprange --src-range 192.168.1.5-192.168.1.124 -m iprange --dst-range 192.168.1.5-192.168.1.124 -j ACCEPT && KLUDGEFREE=Yes
|
|
fi
|
|
fi
|
|
|
|
qt $IPTABLES -A fooX1234 -m recent --update -j ACCEPT && RECENT_MATCH=Yes
|
|
qt $IPTABLES -A fooX1234 -m owner --uid-owner 0 -j ACCEPT && OWNER_MATCH=Yes
|
|
|
|
if qt $IPTABLES -A fooX1234 -m connmark --mark 2 -j ACCEPT; then
|
|
CONNMARK_MATCH=Yes
|
|
qt $IPTABLES -A fooX1234 -m connmark --mark 2/0xFF -j ACCEPT && XCONNMARK_MATCH=Yes
|
|
fi
|
|
|
|
qt $IPTABLES -A fooX1234 -p tcp -m ipp2p --ipp2p -j ACCEPT && IPP2P_MATCH=Yes
|
|
qt $IPTABLES -A fooX1234 -m length --length 10:20 -j ACCEPT && LENGTH_MATCH=Yes
|
|
qt $IPTABLES -A fooX1234 -j REJECT --reject-with icmp-host-prohibited && ENHANCED_REJECT=Yes
|
|
|
|
qt $IPTABLES -A fooX1234 -j ACCEPT -m comment --comment "This is a comment" && COMMENTS=Yes
|
|
|
|
if [ -n "$MANGLE_ENABLED" ]; then
|
|
qt $IPTABLES -t mangle -N fooX1234
|
|
|
|
if qt $IPTABLES -t mangle -A fooX1234 -j MARK --set-mark 1; then
|
|
MARK=Yes
|
|
qt $IPTABLES -t mangle -A fooX1234 -j MARK --and-mark 0xFF && XMARK=Yes
|
|
fi
|
|
|
|
if qt $IPTABLES -t mangle -A fooX1234 -j CONNMARK --save-mark; then
|
|
CONNMARK=Yes
|
|
qt $IPTABLES -t mangle -A fooX1234 -j CONNMARK --save-mark --mask 0xFF && XCONNMARK=Yes
|
|
fi
|
|
|
|
qt $IPTABLES -t mangle -A fooX1234 -j CLASSIFY --set-class 1:1 && CLASSIFY_TARGET=Yes
|
|
qt $IPTABLES -t mangle -F fooX1234
|
|
qt $IPTABLES -t mangle -X fooX1234
|
|
qt $IPTABLES -t mangle -L FORWARD -n && MANGLE_FORWARD=Yes
|
|
fi
|
|
|
|
qt $IPTABLES -t raw -L -n && RAW_TABLE=Yes
|
|
|
|
if qt mywhich ipset; then
|
|
qt ipset -X fooX1234 # Just in case something went wrong the last time
|
|
|
|
if qt ipset -N fooX1234 iphash ; then
|
|
if qt $IPTABLES -A fooX1234 -m set --set fooX1234 src -j ACCEPT; then
|
|
qt $IPTABLES -D fooX1234 -m set --set fooX1234 src -j ACCEPT
|
|
IPSET_MATCH=Yes
|
|
fi
|
|
qt ipset -X fooX1234
|
|
fi
|
|
fi
|
|
|
|
qt $IPTABLES -A fooX1234 -m pkttype --pkt-type broadcast -j ACCEPT && USEPKTTYPE=Yes
|
|
|
|
qt $IPTABLES -F fooX1234
|
|
qt $IPTABLES -X fooX1234
|
|
}
|
|
|
|
report_capabilities() {
|
|
report_capability() # $1 = Capability Description , $2 Capability Setting (if any)
|
|
{
|
|
local setting=
|
|
|
|
[ "x$2" = "xYes" ] && setting="Available" || setting="Not available"
|
|
|
|
echo " " $1: $setting
|
|
}
|
|
|
|
if [ $VERBOSE -gt 1 ]; then
|
|
echo "Shorewall has detected the following iptables/netfilter capabilities:"
|
|
report_capability "NAT" $NAT_ENABLED
|
|
report_capability "Packet Mangling" $MANGLE_ENABLED
|
|
report_capability "Multi-port Match" $MULTIPORT
|
|
[ -n "$MULTIPORT" ] && report_capability "Extended Multi-port Match" $XMULTIPORT
|
|
report_capability "Connection Tracking Match" $CONNTRACK_MATCH
|
|
report_capability "Packet Type Match" $USEPKTTYPE
|
|
report_capability "Policy Match" $POLICY_MATCH
|
|
report_capability "Physdev Match" $PHYSDEV_MATCH
|
|
report_capability "Packet length Match" $LENGTH_MATCH
|
|
report_capability "IP range Match" $IPRANGE_MATCH
|
|
report_capability "Recent Match" $RECENT_MATCH
|
|
report_capability "Owner Match" $OWNER_MATCH
|
|
report_capability "Ipset Match" $IPSET_MATCH
|
|
report_capability "CONNMARK Target" $CONNMARK
|
|
[ -n "$CONNMARK" ] && report_capability "Extended CONNMARK Target" $XCONNMARK
|
|
report_capability "Connmark Match" $CONNMARK_MATCH
|
|
[ -n "$CONNMARK_MATCH" ] && report_capability "Extended Connmark Match" $XCONNMARK_MATCH
|
|
report_capability "Raw Table" $RAW_TABLE
|
|
report_capability "IPP2P Match" $IPP2P_MATCH
|
|
report_capability "CLASSIFY Target" $CLASSIFY_TARGET
|
|
report_capability "Extended REJECT" $ENHANCED_REJECT
|
|
report_capability "Repeat match" $KLUDGEFREE
|
|
report_capability "MARK Target" $MARK
|
|
[ -n "$MARK" ] && report_capability "Extended MARK Target" $XMARK
|
|
report_capability "Mangle FORWARD Chain" $MANGLE_FORWARD
|
|
report_capability "Comments" $COMMENTS
|
|
fi
|
|
|
|
[ -n "$PKTTYPE" ] || USEPKTTYPE=
|
|
|
|
}
|
|
|
|
report_capabilities1() {
|
|
report_capability1() # $1 = Capability
|
|
{
|
|
eval echo $1=\$$1
|
|
}
|
|
|
|
echo "#"
|
|
echo "# Shorewall $VERSION detected the following iptables/netfilter capabilities - $(date)"
|
|
echo "#"
|
|
report_capability1 NAT_ENABLED
|
|
report_capability1 MANGLE_ENABLED
|
|
report_capability1 MULTIPORT
|
|
report_capability1 XMULTIPORT
|
|
report_capability1 CONNTRACK_MATCH
|
|
report_capability1 USEPKTTYPE
|
|
report_capability1 POLICY_MATCH
|
|
report_capability1 PHYSDEV_MATCH
|
|
report_capability1 LENGTH_MATCH
|
|
report_capability1 IPRANGE_MATCH
|
|
report_capability1 RECENT_MATCH
|
|
report_capability1 OWNER_MATCH
|
|
report_capability1 IPSET_MATCH
|
|
report_capability1 CONNMARK
|
|
report_capability1 XCONNMARK
|
|
report_capability1 CONNMARK_MATCH
|
|
report_capability1 XCONNMARK_MATCH
|
|
report_capability1 RAW_TABLE
|
|
report_capability1 IPP2P_MATCH
|
|
report_capability1 CLASSIFY_TARGET
|
|
report_capability1 ENHANCED_REJECT
|
|
report_capability1 KLUDGEFREE
|
|
report_capability1 MARK
|
|
report_capability1 XMARK
|
|
report_capability1 MANGLE_FORWARD
|
|
report_capability1 COMMENTS
|
|
}
|
|
|
|
#
|
|
# Delete IP address
|
|
#
|
|
del_ip_addr() # $1 = address, $2 = interface
|
|
{
|
|
[ $(find_first_interface_address_if_any $2) = $1 ] || qt ip addr del $1 dev $2
|
|
}
|
|
|
|
# Add IP Aliases
|
|
#
|
|
add_ip_aliases() # $* = List of addresses
|
|
{
|
|
local addresses external interface inet cidr rest val arping=$(mywhich arping)
|
|
|
|
address_details()
|
|
{
|
|
#
|
|
# Folks feel uneasy if they don't see all of the same
|
|
# decoration on these IP addresses that they see when their
|
|
# distro's net config tool adds them. In an attempt to reduce
|
|
# the anxiety level, we have the following code which sets
|
|
# the VLSM and BRD from an existing address in the same networks
|
|
#
|
|
# Get all of the lines that contain inet addresses with broadcast
|
|
#
|
|
ip -f inet addr show $interface 2> /dev/null | grep 'inet.*brd' | while read inet cidr rest ; do
|
|
case $cidr in
|
|
*/*)
|
|
if in_network $external $cidr; then
|
|
echo "/${cidr#*/} brd $(broadcastaddress $cidr)"
|
|
break
|
|
fi
|
|
;;
|
|
esac
|
|
done
|
|
}
|
|
|
|
do_one()
|
|
{
|
|
val=$(address_details)
|
|
|
|
ip addr add ${external}${val} dev $interface $label
|
|
[ -n "$arping" ] && qt $arping -U -c 2 -I $interface $external
|
|
echo "$external $interface" >> $STATEDIR/nat
|
|
[ -n "$label" ] && label="with $label"
|
|
progress_message " IP Address $external added to interface $interface $label"
|
|
}
|
|
|
|
progress_message "Adding IP Addresses..."
|
|
|
|
while [ $# -gt 0 ]; do
|
|
external=$1
|
|
interface=$2
|
|
label=
|
|
|
|
if [ "$interface" != "${interface%:*}" ]; then
|
|
label="${interface#*:}"
|
|
interface="${interface%:*}"
|
|
label="label $interface:$label"
|
|
fi
|
|
|
|
shift 2
|
|
|
|
list_search $external $(find_interface_addresses $interface) || do_one
|
|
done
|
|
}
|
|
|
|
detect_gateway() # $1 = interface
|
|
{
|
|
local interface=$1
|
|
#
|
|
# First assume that this is some sort of point-to-point interface
|
|
#
|
|
gateway=$( find_peer $(ip addr ls $interface ) )
|
|
#
|
|
# Maybe there's a default route through this gateway already
|
|
#
|
|
[ -n "$gateway" ] || gateway=$(find_gateway $(ip route ls dev $interface))
|
|
#
|
|
# Last hope -- is there a load-balancing route through the interface?
|
|
#
|
|
[ -n "$gateway" ] || gateway=$(find_nexthop $interface)
|
|
#
|
|
# Be sure we found one
|
|
#
|
|
[ -n "$gateway" ] && echo $gateway
|
|
}
|
|
|
|
#
|
|
# Disable IPV6
|
|
#
|
|
disable_ipv6() {
|
|
local foo="$(ip -f inet6 addr ls 2> /dev/null)"
|
|
|
|
if [ -n "$foo" ]; then
|
|
if qt mywhich ip6tables; then
|
|
ip6tables -P FORWARD DROP
|
|
ip6tables -P INPUT DROP
|
|
ip6tables -P OUTPUT DROP
|
|
ip6tables -F
|
|
ip6tables -X
|
|
ip6tables -A OUTPUT -o lo -j ACCEPT
|
|
ip6tables -A INPUT -i lo -j ACCEPT
|
|
else
|
|
error_message "WARNING: DISABLE_IPV6=Yes in shorewall.conf but this system does not appear to have ip6tables"
|
|
fi
|
|
fi
|
|
}
|
|
|
|
#
|
|
# Add a logging rule.
|
|
#
|
|
do_log_rule_limit() # $1 = log level, $2 = chain, $3 = display Chain $4 = disposition , $5 = rate limit $6=log tag $7=command $... = predicates for the rule
|
|
{
|
|
local level=$1
|
|
local chain=$2
|
|
local displayChain=$3
|
|
local disposition=$4
|
|
local rulenum=
|
|
local limit=
|
|
local tag=
|
|
local command=
|
|
local prefix
|
|
local base=$(chain_base $displayChain)
|
|
local pf
|
|
|
|
limit="${5:-$LOGLIMIT}" # Do this here rather than in the declaration above to appease /bin/ash.
|
|
tag=${6:+$6 }
|
|
command=${7:--A}
|
|
|
|
shift 7
|
|
|
|
if [ -n "$tag" -a -n "$LOGTAGONLY" ]; then
|
|
displayChain=$tag
|
|
tag=
|
|
fi
|
|
|
|
if [ -n "$LOGRULENUMBERS" ]; then
|
|
#
|
|
# Hack for broken printf on some lightweight shells
|
|
#
|
|
[ $(printf "%d" 1) = "1" ] && pf=printf || pf=$(mywhich printf)
|
|
|
|
eval rulenum=\$${base}_logrules
|
|
|
|
rulenum=${rulenum:-1}
|
|
|
|
prefix="$($pf "$LOGFORMAT" $displayChain $rulenum $disposition)${tag}"
|
|
|
|
rulenum=$(($rulenum + 1))
|
|
eval ${base}_logrules=$rulenum
|
|
else
|
|
prefix="$(printf "$LOGFORMAT" $displayChain $disposition)${tag}"
|
|
fi
|
|
|
|
if [ ${#prefix} -gt 29 ]; then
|
|
prefix="$(echo $prefix | truncate 29)"
|
|
error_message "WARNING: Log Prefix shortened to \"$prefix\""
|
|
fi
|
|
|
|
case $level in
|
|
ULOG)
|
|
$IPTABLES $command $chain $@ $limit -j ULOG $LOGPARMS --ulog-prefix "$prefix"
|
|
;;
|
|
*)
|
|
$IPTABLES $command $chain $@ $limit -j LOG $LOGPARMS --log-level $level --log-prefix "$prefix"
|
|
;;
|
|
esac
|
|
|
|
if [ $? -ne 0 ] ; then
|
|
[ -z "$STOPPING" ] && { stop_firewall; exit 2; }
|
|
fi
|
|
}
|
|
|
|
do_log_rule() # $1 = log level, $2 = chain, $3 = disposition , $... = predicates for the rule
|
|
{
|
|
local level=$1
|
|
local chain=$2
|
|
local disposition=$3
|
|
|
|
shift 3
|
|
|
|
do_log_rule_limit $level $chain $chain $disposition "$LOGLIMIT" "" -A $@
|
|
}
|
|
|
|
delete_tc1()
|
|
{
|
|
clear_one_tc() {
|
|
tc qdisc del dev $1 root 2> /dev/null
|
|
tc qdisc del dev $1 ingress 2> /dev/null
|
|
|
|
}
|
|
|
|
run_user_exit tcclear
|
|
|
|
run_ip link list | \
|
|
while read inx interface details; do
|
|
case $inx in
|
|
[0-9]*)
|
|
clear_one_tc ${interface%:}
|
|
;;
|
|
*)
|
|
;;
|
|
esac
|
|
done
|
|
}
|
|
|
|
#
|
|
# Detect a device's MTU
|
|
#
|
|
get_device_mtu() # $1 = device
|
|
{
|
|
local output="$(ip link ls dev $1 2> /dev/null)" # quotes required for /bin/ash
|
|
|
|
if [ -n "$output" ]; then
|
|
echo $(find_mtu $output)
|
|
else
|
|
echo 1500
|
|
fi
|
|
}
|
|
|
|
#
|
|
# Undo changes to routing
|
|
#
|
|
undo_routing() {
|
|
|
|
if [ -z "$NOROUTES" ]; then
|
|
#
|
|
# Restore rt_tables database
|
|
#
|
|
if [ -f ${VARDIR}/rt_tables ]; then
|
|
cp -f ${VARDIR}/rt_tables /etc/iproute2/ && progress_message "/etc/iproute2/rt_tables database restored"
|
|
rm -f ${VARDIR}/rt_tables
|
|
fi
|
|
#
|
|
# Restore the rest of the routing table
|
|
#
|
|
if [ -f ${VARDIR}/undo_routing ]; then
|
|
. ${VARDIR}/undo_routing
|
|
progress_message "Shorewall-generated routing tables and routing rules removed"
|
|
rm -f ${VARDIR}/undo_routing
|
|
fi
|
|
fi
|
|
|
|
}
|
|
|
|
restore_default_route() {
|
|
if [ -z "$NOROUTES" -a -f ${VARDIR}/default_route ]; then
|
|
local default_route= route
|
|
|
|
while read route ; do
|
|
case $route in
|
|
default*)
|
|
if [ -n "$default_route" ]; then
|
|
case "$default_route" in
|
|
*metric*)
|
|
#
|
|
# Don't restore a route with a metric -- we only replace the one with metric == 0
|
|
#
|
|
qt ip route delete default metric 0 && \
|
|
progress_message "Default Route with metric 0 deleted"
|
|
;;
|
|
*)
|
|
qt ip route replace $default_route && \
|
|
progress_message "Default Route (${default_route# }) restored"
|
|
;;
|
|
esac
|
|
|
|
break
|
|
fi
|
|
|
|
default_route="$default_route $route"
|
|
;;
|
|
*)
|
|
default_route="$default_route $route"
|
|
;;
|
|
esac
|
|
done < ${VARDIR}/default_route
|
|
|
|
rm -f ${VARDIR}/default_route
|
|
fi
|
|
}
|
|
|
|
#
|
|
# Determine how to do "echo -e"
|
|
#
|
|
|
|
find_echo() {
|
|
local result
|
|
|
|
result=$(echo "a\tb")
|
|
[ ${#result} -eq 3 ] && { echo echo; return; }
|
|
|
|
result=$(echo -e "a\tb")
|
|
[ ${#result} -eq 3 ] && { echo "echo -e"; return; }
|
|
|
|
result=$(which echo)
|
|
[ -n "$result" ] && { echo "$result -e"; return; }
|
|
|
|
echo echo
|
|
}
|