mirror of
https://gitlab.com/shorewall/code.git
synced 2024-12-30 18:19:04 +01:00
869 lines
34 KiB
XML
869 lines
34 KiB
XML
<?xml version="1.0" encoding="UTF-8"?>
|
|
<!DOCTYPE article PUBLIC "-//OASIS//DTD DocBook XML V4.4//EN"
|
|
"http://www.oasis-open.org/docbook/xml/4.4/docbookx.dtd">
|
|
<article>
|
|
<!--$Id$-->
|
|
|
|
<articleinfo>
|
|
<title>My Network Configuration</title>
|
|
|
|
<authorgroup>
|
|
<author>
|
|
<firstname>Tom</firstname>
|
|
|
|
<surname>Eastep</surname>
|
|
</author>
|
|
</authorgroup>
|
|
|
|
<pubdate><?dbtimestamp format="Y/m/d"?></pubdate>
|
|
|
|
<copyright>
|
|
<year>2009</year>
|
|
|
|
<holder>Thomas M. Eastep</holder>
|
|
</copyright>
|
|
|
|
<legalnotice>
|
|
<para>Permission is granted to copy, distribute and/or modify this
|
|
document under the terms of the GNU Free Documentation License, Version
|
|
1.2 or any later version published by the Free Software Foundation; with
|
|
no Invariant Sections, with no Front-Cover, and with no Back-Cover
|
|
Texts. A copy of the license is included in the section entitled
|
|
<quote><ulink url="GnuCopyright.htm">GNU Free Documentation
|
|
License</ulink></quote>.</para>
|
|
</legalnotice>
|
|
</articleinfo>
|
|
|
|
<caution>
|
|
<para>The ruleset shown in this article uses Shorewall features that are
|
|
not available in Shorewall versions prior to 4.4.0.</para>
|
|
</caution>
|
|
|
|
<section>
|
|
<title>Introduction</title>
|
|
|
|
<para>The configuration described in this article represents the network
|
|
at shorewall.net during the summer of 2009. It uses the following
|
|
Shorewall features:</para>
|
|
|
|
<itemizedlist>
|
|
<listitem>
|
|
<para><ulink url="MultiISP.html">Two Internet
|
|
Interfaces</ulink></para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para>A DMZ with two "systems" using <ulink url="ProxyARP.htm">Proxy
|
|
ARP</ulink> and running in <ulink url="OpenVZ.html">OpenVZ Virtual
|
|
Environments</ulink></para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para><ulink url="6to4.htm">IPv6 Access through a 6to4
|
|
Tunnel</ulink></para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para><ulink url="OPENVPN.html">OpenVPN</ulink> and <ulink
|
|
url="IPSEC-2.6.html">IPSEC</ulink> for access when we are on the
|
|
road.</para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para><ulink url="ipsets.html">Ipsets</ulink></para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para><ulink url="Dynamic.html">Dynamic Zones</ulink></para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para><ulink url="Shorewall_Squid_Usage.html">Transparent proxy using
|
|
Squid</ulink></para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para><ulink url="ManualChains.html">Manual Chains</ulink></para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para><ulink url="traffic_shaping.htm">Traffic Shaping</ulink></para>
|
|
</listitem>
|
|
</itemizedlist>
|
|
|
|
<para>Linux runs the firewall and the servers (although they run in OpenVZ
|
|
containers on the firewall system). Linux is not used natively on any of
|
|
our other systems except for an <ulink url="http://www.hpmini.com">HP mini
|
|
which runs HP Mobile Internet Experience (MIE)</ulink> -- essentially
|
|
Ubuntu Hardy. I rather run Windows natively (either Vista Home Premium or
|
|
XP Professional) and run Linux in VMs under <ulink
|
|
url="http://www.sun.com/software/products/virtualbox/">VirtualBox</ulink>.
|
|
This approach has a number of advantages:</para>
|
|
|
|
<orderedlist>
|
|
<listitem>
|
|
<para>Efficient disk utilization.</para>
|
|
|
|
<para>The virtual disks used by Linux are just files in the NTFS file
|
|
system. There is no need to pre-allocate one or more partitions for
|
|
use by Linux. Some large applications, like Google Earth, are
|
|
installed only on Windows.</para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para>Avoids proprietary hardware issues.</para>
|
|
|
|
<para>The Linux VMs emulate standard hardware that is well-supported
|
|
by Linux.</para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para>Avoids DRM hassles</para>
|
|
|
|
<para>All DRM-protected media can be handled under Windows.</para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para>Websites that don't work with Firefox (or at least with Linux
|
|
Firefox)</para>
|
|
</listitem>
|
|
</orderedlist>
|
|
|
|
<para>VirtualBox is fast (when your processor supports virtualization
|
|
extensions) and very easy to use. I highly recommend it!</para>
|
|
</section>
|
|
|
|
<section>
|
|
<title>Network Topology</title>
|
|
|
|
<para>Our network is diagrammed in the following graphic.</para>
|
|
|
|
<graphic fileref="images/Network2009d.png" />
|
|
|
|
<para>We have accounts with two different ISPs:</para>
|
|
|
|
<orderedlist>
|
|
<listitem>
|
|
<para>Comcast</para>
|
|
|
|
<para>This is a high-speed (20mb/4mb) link with a single dynamic IPv4
|
|
address. We are not allowed to run servers accessible through this
|
|
account.</para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para>Avvanta</para>
|
|
|
|
<para>This is a low-speec (1.5mb/384kbit) link with five static IP
|
|
address. Our servers are accessed through this account.</para>
|
|
</listitem>
|
|
</orderedlist>
|
|
|
|
<para>The wired local network is restricted to my home office. The
|
|
wireless network is managed by a Linksys WRT300N pre-N router which we use
|
|
only as an access point -- its WAN interface is unused and it is
|
|
configured to not do NAT. The wireless network uses WPA2 personal security
|
|
and MAC filtering is enabled in the router. These two factors make it a
|
|
hassle when guests visit with a laptop but provide good security for the
|
|
network.</para>
|
|
</section>
|
|
|
|
<section>
|
|
<title>Shorewall Configuration</title>
|
|
|
|
<para>This section contains exerpts from the Shorewall
|
|
configuration.</para>
|
|
|
|
<para>It is important to keep in mind that parts of my configuration are
|
|
there just to provide a test bed for Shorewall features. So while they
|
|
show correct usage, they don't necessarily provide any useful benefit. I
|
|
have tried to point those out in the sub-sections that follow.</para>
|
|
|
|
<section id="params">
|
|
<title>/etc/shorewall/params</title>
|
|
|
|
<para><programlisting>MIRRORS=62.216.169.37,\
|
|
63.229.2.114,\
|
|
...
|
|
NTPSERVERS=...
|
|
|
|
POPSERVERS=...
|
|
|
|
LOG=ULOG
|
|
|
|
INT_IF=eth1
|
|
EXT_IF=eth2
|
|
COM_IF=eth0
|
|
VPS_IF=venet0</programlisting>As shown, this file defines variables to hold
|
|
the various lists of IP addresses that I need to maintain. To simplify
|
|
network reconfiguration, I also use variables to define the log level
|
|
and the network interfaces.</para>
|
|
</section>
|
|
|
|
<section id="conf">
|
|
<title>/etc/shorewall/shorewall.conf</title>
|
|
|
|
<para><programlisting>###############################################################################
|
|
# S T A R T U P E N A B L E D
|
|
###############################################################################
|
|
STARTUP_ENABLED=Yes
|
|
###############################################################################
|
|
# V E R B O S I T Y
|
|
###############################################################################
|
|
VERBOSITY=0
|
|
###############################################################################
|
|
# C O M P I L E R
|
|
# (setting this to 'perl' requires installation of Shorewall-perl)
|
|
###############################################################################
|
|
SHOREWALL_COMPILER=perl
|
|
###############################################################################
|
|
# L O G G I N G
|
|
###############################################################################
|
|
LOGFILE=/var/log/ulog/syslogemu.log
|
|
STARTUP_LOG=/var/log/shorewall-init.log
|
|
LOG_VERBOSITY=2
|
|
LOGFORMAT="%s:%s:"
|
|
LOGTAGONLY=No
|
|
LOGRATE=
|
|
LOGBURST=
|
|
LOGALLNEW=
|
|
BLACKLIST_LOGLEVEL=
|
|
MACLIST_LOG_LEVEL=
|
|
TCP_FLAGS_LOG_LEVEL=$LOG
|
|
SMURF_LOG_LEVEL=$LOG
|
|
LOG_MARTIANS=No
|
|
###############################################################################
|
|
# L O C A T I O N O F F I L E S A N D D I R E C T O R I E S
|
|
###############################################################################
|
|
IPTABLES=
|
|
IPSET=
|
|
PATH=/usr/local/sbin:/sbin:/bin:/usr/sbin:/usr/bin:/usr/local/bin
|
|
SHOREWALL_SHELL=/bin/sh
|
|
SUBSYSLOCK=
|
|
MODULESDIR=
|
|
CONFIG_PATH=/etc/shorewall:/usr/share/shorewall
|
|
RESTOREFILE=
|
|
IPSECFILE=zones
|
|
LOCKFILE=
|
|
###############################################################################
|
|
# D E F A U L T A C T I O N S / M A C R O S
|
|
###############################################################################
|
|
DROP_DEFAULT="Drop"
|
|
REJECT_DEFAULT="Reject"
|
|
ACCEPT_DEFAULT="none"
|
|
QUEUE_DEFAULT="none"
|
|
###############################################################################
|
|
# R S H / R C P C O M M A N D S
|
|
###############################################################################
|
|
RSH_COMMAND='ssh ${root}@${system} ${command}'
|
|
RCP_COMMAND='scp ${files} ${root}@${system}:${destination}'
|
|
###############################################################################
|
|
# F I R E W A L L O P T I O N S
|
|
###############################################################################
|
|
IP_FORWARDING=Yes
|
|
ADD_IP_ALIASES=No
|
|
ADD_SNAT_ALIASES=No
|
|
RETAIN_ALIASES=No
|
|
TC_ENABLED=Internal
|
|
TC_EXPERT=No
|
|
CLEAR_TC=Yes
|
|
MARK_IN_FORWARD_CHAIN=Yes
|
|
CLAMPMSS=Yes
|
|
ROUTE_FILTER=No
|
|
DETECT_DNAT_IPADDRS=Yes
|
|
MUTEX_TIMEOUT=60
|
|
ADMINISABSENTMINDED=Yes
|
|
BLACKLISTNEWONLY=Yes
|
|
DELAYBLACKLISTLOAD=No
|
|
MODULE_SUFFIX=ko
|
|
DONT_LOAD=
|
|
DISABLE_IPV6=No
|
|
BRIDGING=No
|
|
DYNAMIC_ZONES=No
|
|
PKTTYPE=No
|
|
MACLIST_TABLE=mangle
|
|
MACLIST_TTL=60
|
|
SAVE_IPSETS=No
|
|
MAPOLDACTIONS=No
|
|
FASTACCEPT=No
|
|
IMPLICIT_CONTINUE=Yes
|
|
HIGH_ROUTE_MARKS=Yes
|
|
USE_ACTIONS=Yes
|
|
OPTIMIZE=1
|
|
EXPORTPARAMS=Yes
|
|
EXPAND_POLICIES=Yes
|
|
KEEP_RT_TABLES=No
|
|
DELETE_THEN_ADD=No
|
|
MULTICAST=Yes
|
|
AUTO_COMMENT=Yes
|
|
MANGLE_ENABLED=Yes
|
|
NULL_ROUTE_RFC1918=Yes
|
|
USE_DEFAULT_RT=No
|
|
RESTORE_DEFAULT_ROUTE=No
|
|
FAST_STOP=Yes
|
|
AUTOMAKE=No
|
|
LOG_MARTIANS=Yes
|
|
WIDE_TC_MARKS=Yes
|
|
###############################################################################
|
|
# P A C K E T D I S P O S I T I O N
|
|
###############################################################################
|
|
BLACKLIST_DISPOSITION=DROP
|
|
MACLIST_DISPOSITION=ACCEPT
|
|
TCP_FLAGS_DISPOSITION=DROP
|
|
</programlisting>I don't believe that there is anything remarkable
|
|
there</para>
|
|
</section>
|
|
|
|
<section>
|
|
<title>/etc/shorewall/actions</title>
|
|
|
|
<para><programlisting>#ACTION
|
|
Mirrors # Accept traffic from Shorewall Mirrors
|
|
</programlisting>I make this into an action so the rather long list of rules
|
|
go into their own chain.</para>
|
|
</section>
|
|
|
|
<section>
|
|
<title>/etc/shorewall/action.Mirrors</title>
|
|
|
|
<para><programlisting>#TARGET SOURCE DEST PROTO DEST SOURCE ORIGINAL RATE
|
|
# PORT PORT(S) DEST LIMIT
|
|
COMMENT Accept traffic from Mirrors
|
|
ACCEPT $MIRRORS
|
|
</programlisting>See the <link linkend="rules">rules</link> file -- this
|
|
action is used for rsync traffic.</para>
|
|
</section>
|
|
|
|
<section id="zones">
|
|
<title>/etc/shorewall/zones</title>
|
|
|
|
<para><programlisting>fw firewall
|
|
loc ipv4 #Local Zone
|
|
dmz ipv4 #DMZ
|
|
net ipv4 #Internet
|
|
vpn:loc,net ipsec #IPSEC
|
|
drct:loc ipv4 #Direct internet access</programlisting>The
|
|
<emphasis role="bold">vpn</emphasis> zone is mostly for testing
|
|
Shorewall IPSEC support. It is nested in <emphasis
|
|
role="bold">loc</emphasis> and <emphasis role="bold">net</emphasis> to
|
|
test a feature added in Shorewall 4.4.0. The <emphasis
|
|
role="bold">drct</emphasis> zone is a dynamic zone whose members bypass
|
|
the transparent proxy. Some applications (such as VirtualBox
|
|
registration) don't work through the proxy.</para>
|
|
</section>
|
|
|
|
<section id="interfaces">
|
|
<title>/etc/shorewall/interfaces</title>
|
|
|
|
<para><programlisting>#ZONE INTERFACE BROADCAST OPTIONS
|
|
loc $INT_IF detect dhcp,logmartians=1,routefilter=1,tcpflags
|
|
dmz $VPS_IF detect logmartians=1,routefilter=0,routeback
|
|
net $EXT_IF detect dhcp,blacklist,tcpflags,optional,routefilter=0,nosmurfs,logmartians=0,proxyarp=1
|
|
net $COM_IF detect dhcp,blacklist,tcpflags,optional,upnp,routefilter=0,nosmurfs,logmartians=0
|
|
loc tun+ detect</programlisting>Notice that VPN clients are treated
|
|
the same as local hosts.</para>
|
|
|
|
<para>I set the <emphasis role="bold">proxyarp</emphasis> option on
|
|
$EXT_IF so that</para>
|
|
|
|
<orderedlist numeration="loweralpha">
|
|
<listitem>
|
|
<para>The firewall will respond to ARP who-has requests for the
|
|
servers in the DMZ.</para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para>To keep OpenVZ happy (it issues dire warnings if the option is
|
|
not set on the associated external interface).</para>
|
|
</listitem>
|
|
</orderedlist>
|
|
</section>
|
|
|
|
<section id="hosts">
|
|
<title>/etc/shorewall/hosts</title>
|
|
|
|
<para><programlisting>#ZONE HOST(S) OPTIONS
|
|
vpn $EXT_IF:0.0.0.0/0
|
|
vpn $COM_IF:0.0.0.0/0
|
|
vpn $INT_IF:0.0.0.0/0
|
|
drct $INT_IF:dynamic</programlisting>The <emphasis
|
|
role="bold">vpn</emphasis> zone includes ipsec hosts interfacing from
|
|
either external interface as well as the local interface. <emphasis
|
|
role="bold">drct</emphasis> is defined as dynamic through the local
|
|
interface (recall that it is a sub-zone of <emphasis
|
|
role="bold">loc</emphasis>).</para>
|
|
</section>
|
|
|
|
<section id="policy">
|
|
<title>/etc/shorewall/policy</title>
|
|
|
|
<para><programlisting>#SOURCE DEST POLICY LOG LIMIT:BURST
|
|
# LEVEL
|
|
$FW dmz REJECT $LOG
|
|
$FW all ACCEPT
|
|
loc net ACCEPT -
|
|
loc fw ACCEPT
|
|
loc vpn ACCEPT
|
|
vpn fw ACCEPT
|
|
vpn loc ACCEPT
|
|
net net NONE
|
|
net all DROP $LOG 8/sec:30
|
|
dmz fw REJECT $LOG
|
|
all fw DROP $LOG
|
|
all all REJECT $LOG</programlisting>I'm a bit
|
|
sloppy with my fw<->loc policies -- I should fix that
|
|
someday...</para>
|
|
</section>
|
|
|
|
<section id="accounting">
|
|
<title>/etc/shorewall/accounting</title>
|
|
|
|
<para><programlisting>#ACTION CHAIN SOURCE DESTINATION PROTO DEST SOURCE USER/
|
|
# PORT(S) PORT(S) GROUP
|
|
hp:COUNT accounting $COM_IF $INT_IF:172.20.1.107 UDP
|
|
hp:COUNT accounting $INT_IF:172.20.1.107 $COM_IF UDP
|
|
DONE hp
|
|
|
|
mail:COUNT - $EXT_IF $VPS_IF:206.124.146.0/24 tcp 25
|
|
mail:COUNT - $VPS_IF:206.124.146.0/24 $EXT_IF tcp 25
|
|
DONE mail
|
|
|
|
web - $EXT_IF $VPS_IF:206.124.146.0/24 tcp 80
|
|
web - $EXT_IF $VPS_IF:206.124.146.0/24 tcp 443
|
|
web - $VPS_IF:206.124.146.0/24 $EXT_IF tcp - 80
|
|
web - $VPS_IF:206.124.146.0/24 $EXT_IF tcp - 443
|
|
|
|
COUNT web $EXT_IF $VPS_IF:206.124.146.0/24
|
|
COUNT web $VPS_IF:206.124.146.0/24 $EXT_IF
|
|
</programlisting>The accounting chains are as follows:</para>
|
|
|
|
<orderedlist>
|
|
<listitem>
|
|
<para>hp</para>
|
|
|
|
<para>Counts traffic to/from my work laptop to HP. The VPN users
|
|
NAT-Traversal (UDP 4500) so I just count all UDP traffic to/from my
|
|
work system.</para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para>mail</para>
|
|
|
|
<para>Incoming and outgoing email</para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para>web</para>
|
|
|
|
<para>Website traffic (both HTTP and HTTPS)</para>
|
|
</listitem>
|
|
</orderedlist>
|
|
</section>
|
|
|
|
<section id="blacklist">
|
|
<title>/etc/shorewall/blacklist</title>
|
|
|
|
<para><programlisting>#ADDRESS/SUBNET PROTOCOL PORT
|
|
- udp 1024:1033,1434
|
|
- tcp 57,1433,1434,2401,2745,3127,3306,3410,4899,5554,6101,8081,9898</programlisting>This
|
|
configuration silently drops a few ports that get lots of
|
|
traffic.</para>
|
|
</section>
|
|
|
|
<section id="compile">
|
|
<title>/etc/shorewall/compile</title>
|
|
|
|
<para><programlisting>use strict;
|
|
use Shorewall::Chains;
|
|
|
|
my $chainref = ensure_manual_chain qw/DNS_DDoS/;
|
|
|
|
add_rule $chainref, q(-m string --algo bm --from 30 --to 31 --hex-string "|010000010000000000000000020001|" -j DROP);
|
|
add_rule $chainref, q(-m string --algo bm --from 30 --to 31 --hex-string "|000000010000000000000000020001|" -j DROP);
|
|
add_rule $chainref, q(-j ACCEPT);
|
|
|
|
1;</programlisting>The above was created during a recent DDOS incident that
|
|
targeted DNS servers. It illustrates how manual chains can be
|
|
created.</para>
|
|
</section>
|
|
|
|
<section id="findgw">
|
|
<title>/etc/shorewall/findgw</title>
|
|
|
|
<para><programlisting>if [ -f /var/lib/dhcp3/dhclient.${1}.leases ]; then
|
|
grep 'option routers' /var/lib/dhcp3/dhclient.${1}.leases | tail -n 1 | while read j1 j2 gateway; do echo $gateway | sed 's/;//'; return 0; done
|
|
fi</programlisting>The Comcast line has a dynamic IP address assigned with the
|
|
help of dhclient.</para>
|
|
</section>
|
|
|
|
<section id="isusable">
|
|
<title>/etc/shorewall/isusable</title>
|
|
|
|
<para><programlisting>local status
|
|
status=0
|
|
|
|
[ -f /etc/shorewall/${1}.status ] && status=$(cat /etc/shorewall/${1}.status)
|
|
|
|
return $status</programlisting>For use with <ulink
|
|
url="MultiISP.html#lsm">lsm</ulink>.</para>
|
|
</section>
|
|
|
|
<section id="libprivate">
|
|
<title>/etc/shorewall/lib.private</title>
|
|
|
|
<para><programlisting>start_lsm() {
|
|
killall lsm 2> /dev/null
|
|
cat <<EOF > /etc/lsm/shorewall.conf
|
|
connection {
|
|
name=Avvanta
|
|
checkip=206.124.146.254
|
|
device=$EXT_IF
|
|
ttl=2
|
|
}
|
|
|
|
connection {
|
|
name=Comcast
|
|
checkip=${ETH0_GATEWAY:-71.231.152.1}
|
|
device=$COM_IF
|
|
ttl=1
|
|
}
|
|
EOF
|
|
rm -f /etc/shorewall/*.status
|
|
/usr/sbin/lsm /etc/lsm/lsm.conf >> /var/log/lsm
|
|
}
|
|
</programlisting>This function configures and starts <ulink
|
|
url="MultiISP.html#lsm">lsm</ulink>.</para>
|
|
</section>
|
|
|
|
<section id="masq">
|
|
<title>/etc/shorewall/masq</title>
|
|
|
|
<para><programlisting>#INTERFACE SOURCE ADDRESS
|
|
|
|
COMMENT Masquerade Local Network
|
|
$COM_IF 0.0.0.0/0
|
|
$EXT_IF !206.124.146.0/24 206.124.146.179
|
|
</programlisting>All connections out through Comcast must have the dynamically
|
|
assigned address as their source address. Traffic from hosts without an
|
|
Avvanta public IP address get 206.124.146.179 as their source
|
|
address.</para>
|
|
</section>
|
|
|
|
<section>
|
|
<title>/etc/shorewall/notrack</title>
|
|
|
|
<para><programlisting>#SOURCE DESTINATION PROTO DEST SOURCE USER/
|
|
# PORT(S) PORT(S) GROUP
|
|
net:!192.88.99.1 - 41
|
|
dmz 206.124.146.255 udp
|
|
dmz 255.255.255.255 udp
|
|
loc 172.20.1.255 udp
|
|
loc 255.255.255.255 udp
|
|
$FW 255.255.255.255 udp
|
|
$FW 172.20.1.255 udp
|
|
$FW 206.124.146.255 udp</programlisting>This file omits the
|
|
6to4 traffic originating from 6to4 relays as well as broadcast traffic
|
|
(which Netfilter doesn't handle).</para>
|
|
</section>
|
|
|
|
<section>
|
|
<title>/etc/shorewall/providers</title>
|
|
|
|
<para><programlisting>#NAME NUMBER MARK DUPLICATE INTERFACE GATEWAY OPTIONS COPY
|
|
Avvanta 1 0x10000 main $EXT_IF 206.124.146.254 track,loose,fallback $INT_IF,$VPS_IF,tun*
|
|
Comcast 2 0x20000 main $COM_IF detect track,balance $INT_IF,$VPS_IF,tun*</programlisting>See
|
|
the <ulink url="???">Multi-ISP article</ulink> for an explaination of
|
|
the multi-ISP aspects of this configuration.</para>
|
|
</section>
|
|
|
|
<section id="proxyarp">
|
|
<title>/etc/shorewall/proxyarp</title>
|
|
|
|
<para><programlisting><empty></programlisting>As mentioned <link
|
|
linkend="interfaces">above</link>, I set the proxyarp on the associated
|
|
external interface instead of defining proxy ARP in this file.</para>
|
|
</section>
|
|
|
|
<section id="restored">
|
|
<title>/etc/shorewall/restored</title>
|
|
|
|
<para><programlisting>if [ -z "$(ps ax | grep 'lsm ' | grep -v 'grep ' )" ]; then
|
|
start_lsm
|
|
fi
|
|
|
|
chmod 744 ${VARDIR}/state</programlisting>If lsm isn't running then start it.
|
|
Make the state file world-readable.</para>
|
|
</section>
|
|
|
|
<section id="route_rules">
|
|
<title>/etc/shorewall/route_rules</title>
|
|
|
|
<para><programlisting>#SOURCE DEST PROVIDER PRIORITY
|
|
|
|
- 172.20.0.0/24 main 1000 #OpenVPN clients
|
|
- 206.124.146.177 main 1001 #Servers -- Routes configured by OpenVZ
|
|
- 206.124.146.178 main 1001 #
|
|
- 216.168.3.44 Avvanta 1001 #NNTP -- Does source IP verification
|
|
206.124.146.176/30 - Avvanta 26000 #Avvanta public IP addresses
|
|
206.124.146.180 - Avvanta 26000 #</programlisting>These
|
|
entries simply ensure that outgoing traffic uses the correct
|
|
interface.</para>
|
|
</section>
|
|
|
|
<section id="routestopped">
|
|
<title>/etc/shorewall/routestopped</title>
|
|
|
|
<para><programlisting>#INTERFACE HOST(S) OPTIONS PROTO
|
|
$INT_IF 172.20.1.0/24 source,dest
|
|
$VPS_IF 206.124.146.177,206.124.146.178
|
|
$EXT_IF - notrack 41</programlisting>Keep
|
|
the lights on while Shorewall is stopped.</para>
|
|
</section>
|
|
|
|
<section id="rules">
|
|
<title>/etc/shorewall/rules</title>
|
|
|
|
<para><programlisting>###############################################################################################################################################################################
|
|
#ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL RATE USER/
|
|
# PORT PORT(S) DEST LIMIT GROUP
|
|
###############################################################################################################################################################################
|
|
SECTION ESTABLISHED
|
|
SECTION RELATED
|
|
SECTION NEW
|
|
|
|
REJECT:$LOG loc net tcp 25 #Stop direct loc->net SMTP (Comcast uses submission).
|
|
REJECT:$LOG loc net udp 1025:1031 #MS Messaging
|
|
|
|
COMMENT Stop NETBIOS crap
|
|
|
|
REJECT loc net tcp 137,445
|
|
REJECT loc net udp 137:139
|
|
|
|
COMMENT Stop my idiotic work laptop from sending to the net with an HP source IP address
|
|
|
|
DROP loc:!172.20.0.0/23 net
|
|
|
|
COMMENT
|
|
###############################################################################################################################################################################
|
|
# Local Network to Firewall
|
|
#
|
|
NONAT drct -
|
|
REDIRECT- loc 3128 tcp 80 - !66.199.187.46,172.20.1.108,206.124.146.177,155.98.64.80,81.19.16.0/21
|
|
###############################################################################################################################################################################
|
|
# Local network to DMZ
|
|
#
|
|
ACCEPT loc dmz udp domain,177
|
|
ACCEPT loc dmz tcp ssh,smtp,465,587,www,ftp,imaps,domain,https,5901:5903 -
|
|
ACCEPT loc dmz udp 33434:33524
|
|
###############################################################################################################################################################################
|
|
# Internet to ALL -- drop NewNotSyn packets
|
|
#
|
|
dropNotSyn net fw tcp
|
|
dropNotSyn net loc tcp
|
|
dropNotSyn net dmz tcp
|
|
###############################################################################################################################################################################
|
|
# Internet to DMZ
|
|
#
|
|
DNS_DDoS net dmz udp domain
|
|
ACCEPT net dmz tcp smtp,www,ftp,465,587,imaps,domain,https
|
|
ACCEPT net dmz udp 33434:33454
|
|
Mirrors:none net dmz tcp 873
|
|
ACCEPT net dmz tcp 22 - - s:ssh:3/min:3
|
|
#############################################################################################################################################################
|
|
#################
|
|
#
|
|
# Net to Local
|
|
#
|
|
Limit:$LOG:SSHA,3,60\
|
|
net loc tcp 22
|
|
#
|
|
# BitTorrent from Wireless Network
|
|
#
|
|
#DNAT net:$COM_IF loc:172.20.1.102 tcp 6881:6889
|
|
#DNAT net:$COM_IF loc:172.20.1.102 udp 6881
|
|
#
|
|
# UPnP
|
|
#
|
|
forwardUPnP net loc
|
|
#
|
|
# Silently Handle common probes
|
|
#
|
|
REJECT net loc tcp www,ftp,https
|
|
DROP net loc icmp 8
|
|
###############################################################################################################################################################################
|
|
# DMZ to Internet
|
|
#
|
|
ACCEPT dmz net udp domain,ntp
|
|
REJECT dmz net:$COM_IF tcp smtp
|
|
ACCEPT dmz net tcp echo,ftp,ssh,smtp,whois,domain,www,81,nntp,https,2401,2702,2703,8080
|
|
ACCEPT dmz net:$POPSERVERS tcp pop3
|
|
#
|
|
# Some FTP clients seem prone to sending the PORT command split over two packets. This prevents the FTP connection tracking
|
|
# code from processing the command and setting up the proper expectation. The following rule allows active FTP to work in these cases
|
|
# but logs the connection so I can keep an eye on this potential security hole.
|
|
#
|
|
ACCEPT:$LOG dmz net tcp 1024: 20
|
|
###############################################################################################################################################################################
|
|
# DMZ to Local
|
|
#
|
|
ACCEPT dmz loc tcp 22 - - s:ssh:3/min:3
|
|
###############################################################################################################################################################################
|
|
# DMZ to Firewall -- ntp & snmp Silently reject Auth
|
|
#
|
|
ACCEPT dmz fw tcp 161,ssh
|
|
ACCEPT dmz fw udp 161,ntp
|
|
REJECT dmz fw tcp auth
|
|
###############################################################################################################################################################################
|
|
# Internet to Firewall
|
|
#
|
|
REJECT net fw tcp www,ftp,https
|
|
DROP net fw icmp 8
|
|
ACCEPT net fw udp 33434:33454
|
|
ACCEPT net fw tcp 22 - - s:ssh:3/min:3
|
|
ACCEPT net fw udp 33434:33524
|
|
###############################################################################################################################################################################
|
|
# Firewall to DMZ
|
|
#
|
|
ACCEPT fw dmz tcp domain,www,ftp,ssh,smtp,https,993,465,587,5901
|
|
ACCEPT fw dmz udp domain
|
|
REJECT fw dmz udp 137:139
|
|
##############################################################################################################################################################################
|
|
#
|
|
COMMENT Freenode Probes
|
|
DROP net:82.96.96.3,85.190.0.3 any
|
|
COMMENT
|
|
##############################################################################################################################################################################
|
|
# Allow Ping except where disallowed earlier
|
|
#
|
|
ACCEPT any any icmp 8</programlisting></para>
|
|
</section>
|
|
|
|
<section id="started">
|
|
<title>/etc/shorewall/started</title>
|
|
|
|
<para><programlisting>if [ -z "$(ps ax | grep 'lsm ' | grep -v 'grep ' )" ]; then
|
|
start_lsm
|
|
fi
|
|
|
|
chmod 744 ${VARDIR}/state</programlisting>If lsm isn't running then start it.
|
|
Make the state file world-readable.</para>
|
|
</section>
|
|
|
|
<section id="stopped">
|
|
<title>/etc/shorewall/stopped</title>
|
|
|
|
<para><programlisting>if [ "$COMMAND" = stop -o "$COMMAND" = clear ]; then
|
|
killall lsm 2> /dev/null
|
|
fi
|
|
|
|
chmod 744 ${VARDIR}/state</programlisting>Kill lsm if the command is stop or
|
|
clear. Make the state file world-readable.</para>
|
|
</section>
|
|
|
|
<section>
|
|
<title>/etc/shorewall/tcdevices</title>
|
|
|
|
<para><programlisting>#INTERFACE IN-BANDWITH OUT-BANDWIDTH OPTIONS
|
|
$EXT_IF - 300kbit classify
|
|
$INT_IF - 80mbit classify
|
|
$COM_IF - 4mbit classify,hfsc
|
|
</programlisting>The use of HFSC on the Comcast link is largely to provide a
|
|
test bed for that qdisc; I really don't have any real-time requirement
|
|
such as VOIP.</para>
|
|
</section>
|
|
|
|
<section>
|
|
<title>/etc/shorewall/tcclasses</title>
|
|
|
|
<para><programlisting>#INTERFACE MARK RATE CEIL PRIORITY OPTIONS
|
|
1:110 - full/4 full 1 tcp-ack,tos-minimize-delay
|
|
1:120 - full/4 full 2 flow=nfct-src
|
|
1:130 - full/4 230kbit 3 default,flow=nfct-src
|
|
1:140 - full/4 230kbit 4 flow=nfct-src
|
|
|
|
2:10 - 95*full/100 full 1 flow=dst
|
|
2:100 - 14mbit 20mbit 2
|
|
2:100:101 - 7mbit 20mbit 3 default,flow=dst
|
|
2:100:102 - 7mbit 20mbit 3 flow=dst
|
|
|
|
3:10 - 2mbit:4ms full 1 flow=nfct-src
|
|
3:100 - 2mbit full 2
|
|
3:100:101 - 1mbit full 3 default,flow=nfct-src
|
|
3:100:102 - 1mbit full 3 flow=nfct-src
|
|
</programlisting>Note that most of the outgoing bandwidth on the local
|
|
interface is allocated to one class. That class is used for local
|
|
traffic.</para>
|
|
</section>
|
|
|
|
<section>
|
|
<title>/etc/shorewall/tcfilters</title>
|
|
|
|
<para><programlisting>#INTERFACE: SOURCE DEST PROTO DEST SOURCE TOS LENGTH
|
|
#CLASS PORT(S) PORT(S)
|
|
|
|
# =============================== AVVANTA ====================================
|
|
#
|
|
# Give Highest priority to LSM's pings to the gateway and to DNS queries
|
|
#
|
|
1:110 206.124.146.176 206.124.146.254 icmp
|
|
1:110 206.124.146.177 - udp 53
|
|
#
|
|
# Second Highest priority to IPv6 Tunnel
|
|
#
|
|
1:120 206.124.146.180
|
|
#
|
|
# Lowest priority to bulk traffic
|
|
#
|
|
1:140 206.124.146.177 - tcp - 873 - 2048
|
|
1:140 206.124.146.177 - - - - tos-minimize-cost
|
|
</programlisting>The tcfilters file is only used for the Avvanta provider
|
|
because it has static public IP addresses.</para>
|
|
</section>
|
|
|
|
<section>
|
|
<title>/etc/shorewall/tcrules</title>
|
|
|
|
<para><programlisting>#MARK SOURCE DEST PROTO PORT(S) CLIENT USER TEST LENGTH TOS
|
|
# PORT(S)
|
|
|
|
COMMENT Shape incoming traffic
|
|
|
|
#
|
|
# Most of the bandwidth is reserved for local traffic since the downlinks aren't that fast
|
|
#
|
|
2:10 206.124.146.176/30 $INT_IF
|
|
2:10 206.124.146.177 $INT_IF
|
|
2:10 172.20.1.254 $INT_IF
|
|
#
|
|
# Guarantee 1/2 of the incoming bandwidth for my work system
|
|
#
|
|
2:102 0.0.0.0/0 $INT_IF:172.20.1.107
|
|
|
|
COMMENT Shape outgoing traffic to Comcast
|
|
#
|
|
# Give 1/2 to my work system and add a latency guarantee
|
|
#
|
|
3:10 172.20.1.107 $COM_IF
|
|
#
|
|
# Restrict Torrent uploads
|
|
#
|
|
3:102 172.20.1.0/24 $COM_IF tcp - 6881:6889
|
|
</programlisting>The tcrules file is used to classify traffic that deals with
|
|
the local network and/or with Comcast.</para>
|
|
</section>
|
|
|
|
<section id="tunnels">
|
|
<title>/etc/shorewall/tunnels</title>
|
|
|
|
<para><programlisting>#TYPE ZONE GATEWAY GATEWAY
|
|
# ZONE
|
|
openvpnserver:udp net
|
|
6to4 net
|
|
ipsec net
|
|
ipsec loc
|
|
ipip vpn 0.0.0.0/0</programlisting>The ipip tunnel from
|
|
the vpn zone handles IP compression on IPSEC connections.</para>
|
|
</section>
|
|
</section>
|
|
</article>
|