X-Git-Url: http://git.onelab.eu/?p=ipfw.git;a=blobdiff_plain;f=configuration%2Frc.firewall;fp=configuration%2Frc.firewall;h=2fcc8f4480c67e2a45dcf100bfa9d50e8e0e55fa;hp=0000000000000000000000000000000000000000;hb=28a7fe9d930667786b902af6697c01eb87694173;hpb=2a8b6c544cf5ea3c84f763144c7ecfa79daea969 diff --git a/configuration/rc.firewall b/configuration/rc.firewall new file mode 100755 index 0000000..2fcc8f4 --- /dev/null +++ b/configuration/rc.firewall @@ -0,0 +1,400 @@ +#!/bin/sh - +# Copyright (c) 1996 Poul-Henning Kamp +# 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 AUTHOR 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 AUTHOR 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/rc.firewall,v 1.52.4.1 2008/01/29 00:22:32 dougb Exp $ +# + +# +# Setup system for ipfw(4) firewall service. +# + +# Suck in the configuration variables. +if [ -z "${source_rc_confs_defined}" ]; then + if [ -r /etc/defaults/rc.conf ]; then + . /etc/defaults/rc.conf + source_rc_confs + elif [ -r /etc/rc.conf ]; then + . /etc/rc.conf + fi +fi + +############ +# Define the firewall type in /etc/rc.conf. Valid values are: +# open - will allow anyone in +# client - will try to protect just this machine +# simple - will try to protect a whole network +# closed - totally disables IP services except via lo0 interface +# workstation - will try to protect just this machine using statefull +# firewalling. See below for rc.conf variables used +# UNKNOWN - disables the loading of firewall rules. +# filename - will load the rules in the given filename (full path required) +# +# For ``client'' and ``simple'' the entries below should be customized +# appropriately. + +############ +# +# If you don't know enough about packet filtering, we suggest that you +# take time to read this book: +# +# Building Internet Firewalls, 2nd Edition +# Brent Chapman and Elizabeth Zwicky +# +# O'Reilly & Associates, Inc +# ISBN 1-56592-871-7 +# http://www.ora.com/ +# http://www.oreilly.com/catalog/fire2/ +# +# For a more advanced treatment of Internet Security read: +# +# Firewalls and Internet Security: Repelling the Wily Hacker, 2nd Edition +# William R. Cheswick, Steven M. Bellowin, Aviel D. Rubin +# +# Addison-Wesley / Prentice Hall +# ISBN 0-201-63466-X +# http://www.pearsonhighered.com/ +# http://www.pearsonhighered.com/educator/academic/product/0,3110,020163466X,00.html +# + +setup_loopback () { + ############ + # Only in rare cases do you want to change these rules + # + ${fwcmd} add 100 pass all from any to any via lo0 + ${fwcmd} add 200 deny all from any to 127.0.0.0/8 + ${fwcmd} add 300 deny ip from 127.0.0.0/8 to any +} + +if [ -n "${1}" ]; then + firewall_type="${1}" +fi + +############ +# Set quiet mode if requested +# +case ${firewall_quiet} in +[Yy][Ee][Ss]) + fwcmd="/sbin/ipfw -q" + ;; +*) + fwcmd="/sbin/ipfw" + ;; +esac + +############ +# Flush out the list before we begin. +# +${fwcmd} -f flush + +setup_loopback + +############ +# Network Address Translation. All packets are passed to natd(8) +# before they encounter your remaining rules. The firewall rules +# will then be run again on each packet after translation by natd +# starting at the rule number following the divert rule. +# +# For ``simple'' firewall type the divert rule should be put to a +# different place to not interfere with address-checking rules. +# +case ${firewall_type} in +[Oo][Pp][Ee][Nn]|[Cc][Ll][Ii][Ee][Nn][Tt]) + case ${natd_enable} in + [Yy][Ee][Ss]) + if [ -n "${natd_interface}" ]; then + ${fwcmd} add 50 divert natd ip4 from any to any via ${natd_interface} + fi + ;; + esac + case ${firewall_nat_enable} in + [Yy][Ee][Ss]) + if [ -n "${firewall_nat_interface}" ]; then + ${fwcmd} nat 123 config if ${firewall_nat_interface} log + ${fwcmd} add 50 nat 123 ip4 from any to any via ${firewall_nat_interface} + fi + ;; + esac +esac + +############ +# If you just configured ipfw in the kernel as a tool to solve network +# problems or you just want to disallow some particular kinds of traffic +# then you will want to change the default policy to open. You can also +# do this as your only action by setting the firewall_type to ``open''. +# +# ${fwcmd} add 65000 pass all from any to any + + +# Prototype setups. +# +case ${firewall_type} in +[Oo][Pp][Ee][Nn]) + ${fwcmd} add 65000 pass all from any to any + ;; + +[Cc][Ll][Ii][Ee][Nn][Tt]) + ############ + # This is a prototype setup that will protect your system somewhat + # against people from outside your own network. + ############ + + # set these to your network and netmask and ip + net="192.0.2.0" + mask="255.255.255.0" + ip="192.0.2.1" + + # Allow any traffic to or from my own net. + ${fwcmd} add pass all from ${ip} to ${net}:${mask} + ${fwcmd} add pass all from ${net}:${mask} to ${ip} + + # Allow TCP through if setup succeeded + ${fwcmd} add pass tcp from any to any established + + # Allow IP fragments to pass through + ${fwcmd} add pass all from any to any frag + + # Allow setup of incoming email + ${fwcmd} add pass tcp from any to me 25 setup + + # Allow setup of outgoing TCP connections only + ${fwcmd} add pass tcp from me to any setup + + # Disallow setup of all other TCP connections + ${fwcmd} add deny tcp from any to any setup + + # Allow DNS queries out in the world + ${fwcmd} add pass udp from me to any 53 keep-state + + # Allow NTP queries out in the world + ${fwcmd} add pass udp from me to any 123 keep-state + + # Everything else is denied by default, unless the + # IPFIREWALL_DEFAULT_TO_ACCEPT option is set in your kernel + # config file. + ;; + +[Ss][Ii][Mm][Pp][Ll][Ee]) + ############ + # This is a prototype setup for a simple firewall. Configure this + # machine as a DNS and NTP server, and point all the machines + # on the inside at this machine for those services. + ############ + + # set these to your outside interface network and netmask and ip + oif="ed0" + onet="192.0.2.0" + omask="255.255.255.240" + oip="192.0.2.1" + + # set these to your inside interface network and netmask and ip + iif="ed1" + inet="192.0.2.16" + imask="255.255.255.240" + iip="192.0.2.17" + + # Stop spoofing + ${fwcmd} add deny all from ${inet}:${imask} to any in via ${oif} + ${fwcmd} add deny all from ${onet}:${omask} to any in via ${iif} + + # Stop RFC1918 nets on the outside interface + ${fwcmd} add deny all from any to 10.0.0.0/8 via ${oif} + ${fwcmd} add deny all from any to 172.16.0.0/12 via ${oif} + ${fwcmd} add deny all from any to 192.168.0.0/16 via ${oif} + + # Stop draft-manning-dsua-03.txt (1 May 2000) nets (includes RESERVED-1, + # DHCP auto-configuration, NET-TEST, MULTICAST (class D), and class E) + # on the outside interface + ${fwcmd} add deny all from any to 0.0.0.0/8 via ${oif} + ${fwcmd} add deny all from any to 169.254.0.0/16 via ${oif} + ${fwcmd} add deny all from any to 192.0.2.0/24 via ${oif} + ${fwcmd} add deny all from any to 224.0.0.0/4 via ${oif} + ${fwcmd} add deny all from any to 240.0.0.0/4 via ${oif} + + # Network Address Translation. This rule is placed here deliberately + # so that it does not interfere with the surrounding address-checking + # rules. If for example one of your internal LAN machines had its IP + # address set to 192.0.2.1 then an incoming packet for it after being + # translated by natd(8) would match the `deny' rule above. Similarly + # an outgoing packet originated from it before being translated would + # match the `deny' rule below. + case ${natd_enable} in + [Yy][Ee][Ss]) + if [ -n "${natd_interface}" ]; then + ${fwcmd} add divert natd all from any to any via ${natd_interface} + fi + ;; + esac + + # Stop RFC1918 nets on the outside interface + ${fwcmd} add deny all from 10.0.0.0/8 to any via ${oif} + ${fwcmd} add deny all from 172.16.0.0/12 to any via ${oif} + ${fwcmd} add deny all from 192.168.0.0/16 to any via ${oif} + + # Stop draft-manning-dsua-03.txt (1 May 2000) nets (includes RESERVED-1, + # DHCP auto-configuration, NET-TEST, MULTICAST (class D), and class E) + # on the outside interface + ${fwcmd} add deny all from 0.0.0.0/8 to any via ${oif} + ${fwcmd} add deny all from 169.254.0.0/16 to any via ${oif} + ${fwcmd} add deny all from 192.0.2.0/24 to any via ${oif} + ${fwcmd} add deny all from 224.0.0.0/4 to any via ${oif} + ${fwcmd} add deny all from 240.0.0.0/4 to any via ${oif} + + # Allow TCP through if setup succeeded + ${fwcmd} add pass tcp from any to any established + + # Allow IP fragments to pass through + ${fwcmd} add pass all from any to any frag + + # Allow setup of incoming email + ${fwcmd} add pass tcp from any to ${oip} 25 setup + + # Allow access to our DNS + ${fwcmd} add pass tcp from any to ${oip} 53 setup + ${fwcmd} add pass udp from any to ${oip} 53 + ${fwcmd} add pass udp from ${oip} 53 to any + + # Allow access to our WWW + ${fwcmd} add pass tcp from any to ${oip} 80 setup + + # Reject&Log all setup of incoming connections from the outside + ${fwcmd} add deny log tcp from any to any in via ${oif} setup + + # Allow setup of any other TCP connection + ${fwcmd} add pass tcp from any to any setup + + # Allow DNS queries out in the world + ${fwcmd} add pass udp from ${oip} to any 53 keep-state + + # Allow NTP queries out in the world + ${fwcmd} add pass udp from ${oip} to any 123 keep-state + + # Everything else is denied by default, unless the + # IPFIREWALL_DEFAULT_TO_ACCEPT option is set in your kernel + # config file. + ;; + +[Ww][Oo][Rr][Kk][Ss][Tt][Aa][Tt][Ii][Oo][Nn]) + # Configuration: + # firewall_myservices: List of TCP ports on which this host + # offers services. + # firewall_allowservices: List of IPs which has access to + # $firewall_myservices. + # firewall_trusted: List of IPs which has full access + # to this host. Be very carefull + # when setting this. This option can + # seriously degrade the level of + # protection provided by the firewall. + # firewall_logdeny: Boolean (YES/NO) specifying if the + # default denied packets should be + # logged (in /var/log/security). + # firewall_nologports: List of TCP/UDP ports for which + # denied incomming packets are not + # logged. + + # Allow packets for which a state has been built. + ${fwcmd} add check-state + + # For services permitted below. + ${fwcmd} add pass tcp from me to any established + + # Allow any connection out, adding state for each. + ${fwcmd} add pass tcp from me to any setup keep-state + ${fwcmd} add pass udp from me to any keep-state + ${fwcmd} add pass icmp from me to any keep-state + + # Allow DHCP. + ${fwcmd} add pass udp from 0.0.0.0 68 to 255.255.255.255 67 out + ${fwcmd} add pass udp from any 67 to me 68 in + ${fwcmd} add pass udp from any 67 to 255.255.255.255 68 in + # Some servers will ping the IP while trying to decide if it's + # still in use. + ${fwcmd} add pass icmp from any to any icmptype 8 + + # Allow "mandatory" ICMP in. + ${fwcmd} add pass icmp from any to any icmptype 3,4,11 + + # Add permits for this workstations published services below + # Only IPs and nets in firewall_allowservices is allowed in. + # If you really wish to let anyone use services on your + # workstation, then set "firewall_allowservices='any'" in /etc/rc.conf + # + # Note: We don't use keep-state as that would allow DoS of + # our statetable. + # You can add 'keep-state' to the lines for slightly + # better performance if you fell that DoS of your + # workstation won't be a problem. + # + for i in ${firewall_allowservices} ; do + for j in ${firewall_myservices} ; do + ${fwcmd} add pass tcp from $i to me $j + done + done + + # Allow all connections from trusted IPs. + # Playing with the content of firewall_trusted could seriously + # degrade the level of protection provided by the firewall. + for i in ${firewall_trusted} ; do + ${fwcmd} add pass ip from $i to me + done + + ${fwcmd} add 65000 count ip from any to any + + # Drop packets to ports where we don't want logging + for i in ${firewall_nologports} ; do + ${fwcmd} add deny { tcp or udp } from any to any $i in + done + + # Broadcasts and muticasts + ${fwcmd} add deny ip from any to 255.255.255.255 + ${fwcmd} add deny ip from any to 224.0.0.0/24 in # XXX + + # Noise from routers + ${fwcmd} add deny udp from any to any 520 in + + # Noise from webbrowsing. + # The statefull filter is a bit agressive, and will cause some + # connection teardowns to be logged. + ${fwcmd} add deny tcp from any 80,443 to any 1024-65535 in + + # Deny and (if wanted) log the rest unconditionally. + log="" + if [ ${firewall_logdeny:-x} = "YES" -o ${firewall_logdeny:-x} = "yes" ] ; then + log="log logamount 500" # The default of 100 is too low. + sysctl net.inet.ip.fw.verbose=1 >/dev/null + fi + ${fwcmd} add deny $log ip from any to any + ;; + +[Cc][Ll][Oo][Ss][Ee][Dd]) + ${fwcmd} add 65000 deny ip from any to any + ;; +[Uu][Nn][Kk][Nn][Oo][Ww][Nn]) + ;; +*) + if [ -r "${firewall_type}" ]; then + ${fwcmd} ${firewall_flags} ${firewall_type} + fi + ;; +esac