mirror of
https://gitlab.com/shorewall/code.git
synced 2024-11-23 08:03:11 +01:00
fb33fd9aa1
git-svn-id: https://shorewall.svn.sourceforge.net/svnroot/shorewall/trunk@4587 fbd18981-670d-0410-9b5c-8dc0c1a9a2bb
880 lines
27 KiB
XML
880 lines
27 KiB
XML
<?xml version="1.0" encoding="UTF-8"?>
|
|
<!DOCTYPE article PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
|
|
"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
|
|
<article id="PPTP">
|
|
<!--$Id$-->
|
|
|
|
<articleinfo>
|
|
<title>PPTP - Unmaintained</title>
|
|
|
|
<authorgroup>
|
|
<author>
|
|
<firstname>Tom</firstname>
|
|
|
|
<surname>Eastep</surname>
|
|
</author>
|
|
</authorgroup>
|
|
|
|
<pubdate><?dbtimestamp format="Y/m/d"?></pubdate>
|
|
|
|
<copyright>
|
|
<year>2001</year>
|
|
|
|
<year>2002</year>
|
|
|
|
<year>2003</year>
|
|
|
|
<year>2004</year>
|
|
|
|
<year>2005</year>
|
|
|
|
<year>2006</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>
|
|
|
|
<revhistory>
|
|
<revision>
|
|
<revnumber>1.4</revnumber>
|
|
|
|
<date>2004-11-02</date>
|
|
|
|
<authorinitials>TE</authorinitials>
|
|
|
|
<revremark>Added link to Greg Kops's tutorial.</revremark>
|
|
</revision>
|
|
|
|
<revision>
|
|
<revnumber>1.3</revnumber>
|
|
|
|
<date>2004-05-22</date>
|
|
|
|
<authorinitials>TE</authorinitials>
|
|
|
|
<revremark>Warning about PPTP conntrack patch and GRE
|
|
tunnels.</revremark>
|
|
</revision>
|
|
|
|
<revision>
|
|
<revnumber>1.2</revnumber>
|
|
|
|
<date>2004-04-15</date>
|
|
|
|
<authorinitials>TE</authorinitials>
|
|
|
|
<revremark>Revised instructions regarding PPTP conntrack
|
|
patch.</revremark>
|
|
</revision>
|
|
|
|
<revision>
|
|
<revnumber>1.1</revnumber>
|
|
|
|
<date>2003-12-23</date>
|
|
|
|
<authorinitials>TE</authorinitials>
|
|
|
|
<revremark>Added note about PPTP module support in Bering
|
|
1.2</revremark>
|
|
</revision>
|
|
</revhistory>
|
|
|
|
<abstract>
|
|
<para>Shorewall easily supports PPTP in a number of
|
|
configurations.</para>
|
|
</abstract>
|
|
</articleinfo>
|
|
|
|
<warning>
|
|
<para><emphasis role="bold">This document is no longer maintained. Any
|
|
volunteers?</emphasis></para>
|
|
</warning>
|
|
|
|
<section>
|
|
<title>Overview</title>
|
|
|
|
<note>
|
|
<para>I am no longer attempting to maintain MPPE patches for current
|
|
Linux kernel's and pppd. I recommend that you refer to the following
|
|
URLs for information about installing MPPE into your kernel and
|
|
pppd.</para>
|
|
</note>
|
|
|
|
<para>The <ulink url="http://pptpclient.sourceforge.net">Linux PPTP client
|
|
project</ulink> has a nice GUI for configuring and managing VPN
|
|
connections where your Linux system is the PPTP client. This is what I
|
|
currently use. I am no longer running PoPToP but rather I use the PPTP
|
|
Server included with XP Professional (see <ulink
|
|
url="PPTP.htm#ServerBehind">PPTP Server running behind your
|
|
Firewall</ulink> below).</para>
|
|
|
|
<variablelist>
|
|
<varlistentry>
|
|
<term><ulink
|
|
url="http://pptpclient.sourceforge.net">http://pptpclient.sourceforge.net</ulink></term>
|
|
|
|
<listitem>
|
|
<para>Everything you need to run a PPTP client.</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><ulink
|
|
url="http://www.poptop.org">http://www.poptop.org</ulink></term>
|
|
|
|
<listitem>
|
|
<para>The <quote>kernelmod</quote> package can be used to quickly
|
|
install MPPE into your kernel without rebooting.</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><ulink
|
|
url="http://devel.elucid8design.com/el8/devel/tutorials/pptp.php">http://devel.elucid8design.com/el8/devel/tutorials/pptp.php</ulink></term>
|
|
|
|
<listitem>
|
|
<para>A nice tutorial for installing a PPTP server on Fedora.</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
</variablelist>
|
|
|
|
<para>I am leaving the instructions for building MPPE-enabled kernels and
|
|
pppd in the text below for those who may wish to obtain the relevant
|
|
current patches and <quote>roll their own</quote>.</para>
|
|
</section>
|
|
|
|
<section>
|
|
<title>Preliminary Reading</title>
|
|
|
|
<para>I recommend reading the <ulink url="VPNBasics.html">VPN
|
|
Basics</ulink> article if you plan to implement any type of VPN.</para>
|
|
</section>
|
|
|
|
<section id="ServerFW">
|
|
<title>PPTP Server Running on your Firewall</title>
|
|
|
|
<para>I will try to give you an idea of how to set up a PPTP server on
|
|
your firewall system. This isn't a detailed HOWTO but rather an example of
|
|
how I have set up a working PPTP server on my own firewall.</para>
|
|
|
|
<para>The steps involved are:</para>
|
|
|
|
<orderedlist>
|
|
<listitem>
|
|
<para><xref linkend="PatchPppd" /></para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para><xref linkend="PatchKernel" /></para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para><xref linkend="Samba" /></para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para><xref linkend="ConfigPppd" /></para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para><xref linkend="ConfigPptpd" /></para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para><xref linkend="ConfigFw" /></para>
|
|
</listitem>
|
|
</orderedlist>
|
|
|
|
<section id="PatchPppd">
|
|
<title>Patching and building pppd</title>
|
|
|
|
<para>To run pppd on a 2.4 kernel, you need the pppd 2.4.1 or later. The
|
|
primary site for releases of pppd is <ulink
|
|
url="ftp://ftp.samba.org/pub/ppp">ftp://ftp.samba.org/pub/ppp</ulink>.</para>
|
|
|
|
<para>You will need the following patches:</para>
|
|
|
|
<simplelist>
|
|
<member><ulink
|
|
url="http://www.shorewall.net/pub/shorewall/pptp/ppp-2.4.1-openssl-0.9.6-mppe-patch.gz">http://www.shorewall.net/pub/shorewall/pptp/ppp-2.4.1-openssl-0.9.6-mppe-patch.gz</ulink></member>
|
|
|
|
<member><ulink
|
|
url="http://www.shorewall.net/pub/shorewall/pptp/ppp-2.4.1-MSCHAPv2-fix.patch.gz">http://www.shorewall.net/pub/shorewall/pptp/ppp-2.4.1-MSCHAPv2-fix.patch.gz</ulink></member>
|
|
</simplelist>
|
|
|
|
<para>You may also want the following patch if you want to require
|
|
remote hosts to use encryption:</para>
|
|
|
|
<simplelist>
|
|
<member><ulink
|
|
url="ftp://ftp.shorewall.net/pub/shorewall/pptp/require-mppe.diff">ftp://ftp.shorewall.net/pub/shorewall/pptp/require-mppe.diff</ulink></member>
|
|
</simplelist>
|
|
|
|
<para>Un-tar the pppd source and uncompress the patches into one
|
|
directory (the patches and the ppp-2.4.1 directory are all in a single
|
|
parent directory):</para>
|
|
|
|
<programlisting>cd ppp-2.4.1
|
|
patch -p1 < ../ppp-2.4.0-openssl-0.9.6-mppe.patch
|
|
patch -p1 < ../ppp-2.4.1-MSCHAPv2-fix.patch
|
|
(Optional) patch -p1 < ../require-mppe.diff
|
|
./configure
|
|
make</programlisting>
|
|
|
|
<para>You will need to install the resulting binary on your firewall
|
|
system. To do that, I NFS mount my source filesystem and use <quote>make
|
|
install</quote> from the ppp-2.4.1 directory.</para>
|
|
</section>
|
|
|
|
<section id="PatchKernel">
|
|
<title>Patching and building your Kernel</title>
|
|
|
|
<para>You will need one of the following patches depending on your
|
|
kernel version:</para>
|
|
|
|
<simplelist>
|
|
<member>http://www.shorewall.net/pub/shorewall/pptp/linux-2.4.4-openssl-0.9.6a-mppe-patch.gz</member>
|
|
|
|
<member>http://www.shorewall/net/pub/shorewall/pptp/linux-2.4.16-openssl-0.9.6b-mppe-patch.gz</member>
|
|
</simplelist>
|
|
|
|
<para>Uncompress the patch into the same directory where your top-level
|
|
kernel source is located and:</para>
|
|
|
|
<programlisting>cd <your GNU/Linux source top-level directory>
|
|
patch -p1 < ../linux-2.4.16-openssl-0.9.6b-mppe.patch</programlisting>
|
|
|
|
<para>Now configure your kernel. Here is my ppp configuration:</para>
|
|
|
|
<graphic fileref="images/ppp.jpg" />
|
|
</section>
|
|
|
|
<section id="Samba">
|
|
<title>Configuring Samba</title>
|
|
|
|
<para>You will need a WINS server (Samba configured to run as a WINS
|
|
server is fine). Global section from /etc/samba/smb.conf on my WINS
|
|
server (192.168.1.3) is:</para>
|
|
|
|
<programlisting>[global]
|
|
workgroup = TDM-NSTOP
|
|
netbios name = WOOKIE
|
|
server string = GNU/Linux Box
|
|
encrypt passwords = Yes
|
|
log file = /var/log/samba/%m.log
|
|
max log size = 0
|
|
socket options = TCP_NODELAY SO_RCVBUF=8192 SO_SNDBUF=8192
|
|
os level = 65
|
|
domain master = True
|
|
preferred master = True
|
|
dns proxy = No
|
|
wins support = Yes
|
|
printing = lprng
|
|
|
|
[homes]
|
|
comment = Home Directories
|
|
valid users = %S
|
|
read only = No
|
|
create mask = 0664
|
|
directory mask = 0775
|
|
|
|
[printers]
|
|
comment = All Printers
|
|
path = /var/spool/samba
|
|
printable = Yes</programlisting>
|
|
</section>
|
|
|
|
<section id="ConfigPppd">
|
|
<title>Configuring pppd</title>
|
|
|
|
<para>Here is a copy of my /etc/ppp/options.poptop file:</para>
|
|
|
|
<programlisting>ipparam PoPToP
|
|
lock
|
|
mtu 1490
|
|
mru 1490
|
|
ms-wins 192.168.1.3
|
|
ms-dns 206.124.146.177
|
|
multilink
|
|
proxyarp
|
|
auth
|
|
+chap
|
|
+chapms
|
|
+chapms-v2
|
|
ipcp-accept-local
|
|
ipcp-accept-remote
|
|
lcp-echo-failure 30
|
|
lcp-echo-interval 5
|
|
deflate 0
|
|
mppe-128
|
|
mppe-stateless
|
|
require-mppe
|
|
require-mppe-stateless</programlisting>
|
|
|
|
<note>
|
|
<itemizedlist>
|
|
<listitem>
|
|
<para>System 192.168.1.3 acts as a WINS server so I have included
|
|
that IP as the <quote>ms-wins</quote> value.</para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para>I have pointed the remote clients at my DNS server -- it has
|
|
external address 206.124.146.177.</para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para>I am requiring 128-bit stateless compression (my kernel is
|
|
built with the <quote>require-mppe.diff</quote> patch mentioned
|
|
above.</para>
|
|
</listitem>
|
|
</itemizedlist>
|
|
</note>
|
|
|
|
<para>Here's my /etc/ppp/chap-secrets:</para>
|
|
|
|
<programlisting>Secrets for authentication using CHAP
|
|
# client server secret IP addresses
|
|
CPQTDM\\TEastep * <shhhhhh> 192.168.1.7
|
|
TEastep * <shhhhhh> 192.168.1.7</programlisting>
|
|
|
|
<para>I am the only user who connects to the server but I may connect
|
|
either with or without a domain being specified. The system I connect
|
|
from is my laptop so I give it the same IP address when tunneled in at
|
|
it has when I use its wireless LAN card around the house.</para>
|
|
|
|
<para>You will also want the following in /etc/modules.conf:</para>
|
|
|
|
<programlisting>alias ppp-compress-18 ppp_mppe
|
|
alias ppp-compress-21 bsd_comp
|
|
alias ppp-compress-24 ppp_deflate
|
|
alias ppp-compress-26 ppp_deflate</programlisting>
|
|
</section>
|
|
|
|
<section id="ConfigPptpd">
|
|
<title>Configuring pptpd</title>
|
|
|
|
<para>PoPTop (pptpd) is available from <ulink
|
|
url="http://www.poptop.org/">http://www.poptop.org/</ulink>.</para>
|
|
|
|
<para>Here is a copy of my /etc/pptpd.conf file:</para>
|
|
|
|
<programlisting>option /etc/ppp/options.poptop
|
|
speed 115200
|
|
localip 192.168.1.254
|
|
remoteip 192.168.1.33-38</programlisting>
|
|
|
|
<note>
|
|
<itemizedlist>
|
|
<listitem>
|
|
<para>I specify the /etc/ppp/options.poptop file as my ppp options
|
|
file (I have several).</para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para>The local IP is the same as my internal interface's
|
|
(192.168.1.254).</para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para>I have assigned a remote IP range that overlaps my local
|
|
network. This, together with <quote>proxyarp</quote> in my
|
|
/etc/ppp/options.poptop file make the remote hosts look like they
|
|
are part of the local subnetwork.</para>
|
|
</listitem>
|
|
</itemizedlist>
|
|
</note>
|
|
|
|
<para>I use this file to start/stop pptpd -- I have this in
|
|
/etc/init.d/pptpd:</para>
|
|
|
|
<programlisting>#!/bin/sh
|
|
#
|
|
# /etc/rc.d/init.d/pptpd
|
|
#
|
|
# chkconfig: 5 12 85
|
|
# description: control pptp server
|
|
#
|
|
|
|
case "$1" in
|
|
start)
|
|
echo 1 > /proc/sys/net/ipv4/ip_forward
|
|
modprobe ppp_async
|
|
modprobe ppp_generic
|
|
modprobe ppp_mppe
|
|
modprobe slhc
|
|
if /usr/local/sbin/pptpd; then
|
|
touch /var/lock/subsys/pptpd
|
|
fi
|
|
;;
|
|
stop)
|
|
killall pptpd
|
|
rm -f /var/lock/subsys/pptpd
|
|
;;
|
|
restart)
|
|
killall pptpd
|
|
if /usr/local/sbin/pptpd; then
|
|
touch /var/lock/subsys/pptpd
|
|
fi
|
|
;;
|
|
status)
|
|
ifconfig
|
|
;;
|
|
*)
|
|
echo "Usage: $0 {start|stop|restart|status}"
|
|
;;
|
|
esac</programlisting>
|
|
</section>
|
|
|
|
<section id="ConfigFw">
|
|
<title>Configuring Shorewall</title>
|
|
|
|
<section>
|
|
<title>Basic Setup</title>
|
|
|
|
<para>Here' a basic setup that treats your remote users as if they
|
|
were part of your <emphasis role="bold">loc</emphasis> zone. Note that
|
|
if your primary internet connection uses ppp0, then be sure that
|
|
<emphasis role="bold">loc</emphasis> follows <emphasis
|
|
role="bold">net</emphasis> in /etc/shorewall/zones.</para>
|
|
|
|
<para><filename>/etc/shorewall/tunnels</filename>:</para>
|
|
|
|
<programlisting>#TYPE ZONE GATEWAY GATEWAY ZONE
|
|
pptpserver net 0.0.0.0/0</programlisting>
|
|
|
|
<para><filename>/etc/shorewall/interfaces</filename>:</para>
|
|
|
|
<programlisting>#ZONE INTERFACE BROADCAST OPTIONS
|
|
loc ppp+</programlisting>
|
|
</section>
|
|
|
|
<section>
|
|
<title>Remote Users in a Separate Zone</title>
|
|
|
|
<para>If you want to place your remote users in their own zone so that
|
|
you can control connections between these users and the local network,
|
|
follow this example. Note that if your primary internet connection
|
|
uses ppp0 then be sure that <emphasis role="bold">vpn</emphasis>
|
|
follows <emphasis role="bold">net</emphasis> in /etc/shorewall/zones
|
|
as shown below.</para>
|
|
|
|
<para><filename>/etc/shorewall/tunnels</filename>:</para>
|
|
|
|
<programlisting>#TYPE ZONE GATEWAY GATEWAY ZONE
|
|
pptpserver net 0.0.0.0/0</programlisting>
|
|
|
|
<para><filename>/etc/shorewall/zones</filename>:</para>
|
|
|
|
<programlisting>#ZONE DISPLAY COMMENTS
|
|
net Internet The Internet
|
|
loc Local Local Network
|
|
vpn VPN Remote Users</programlisting>
|
|
|
|
<para><filename>/etc/shorewall/interfaces</filename>:</para>
|
|
|
|
<programlisting>#ZONE INTERFACE BROADCAST OPTIONS
|
|
net eth0 206.124.146.255 norfc1918
|
|
loc eth2 192.168.10.255
|
|
vpn ppp+</programlisting>
|
|
|
|
<para>Your policies and rules may now be configured for traffic
|
|
to/from the <emphasis role="bold">vpn</emphasis> zone.</para>
|
|
</section>
|
|
|
|
<section>
|
|
<title>Multiple Remote Networks</title>
|
|
|
|
<para>Often there will be situations where you want multiple
|
|
connections from remote networks with these networks having different
|
|
firewalling requirements.<graphic
|
|
fileref="images/MultiPPTP.png" /></para>
|
|
|
|
<para>Here's how you configure this in Shorewall. Note that if your
|
|
primary internet connection uses ppp0 then be sure that the <emphasis
|
|
role="bold">vpn{1-3}</emphasis> zones follows <emphasis
|
|
role="bold">net</emphasis> in /etc/shorewall/zones as shown
|
|
below.</para>
|
|
|
|
<para><filename>/etc/shorewall/tunnels</filename>:</para>
|
|
|
|
<programlisting>#TYPE ZONE GATEWAY GATEWAY ZONE
|
|
pptpserver net 0.0.0.0/0</programlisting>
|
|
|
|
<para><filename>/etc/shorewall/zones</filename>:</para>
|
|
|
|
<programlisting>#ZONE DISPLAY COMMENTS
|
|
net Internet The Internet
|
|
loc Local Local Network
|
|
vpn1 Remote1 Remote Network 1
|
|
vpn2 Remote2 Remote Network 2
|
|
vpn3 Remote3 Remote Network 3</programlisting>
|
|
|
|
<para><filename>/etc/shorewall/interfaces</filename>:</para>
|
|
|
|
<programlisting>#ZONE INTERFACE BROADCAST OPTIONS
|
|
net eth0 206.124.146.255 norfc1918
|
|
loc eth2 192.168.10.255
|
|
- ppp+</programlisting>
|
|
|
|
<para><filename>/etc/shorewall/hosts</filename>:</para>
|
|
|
|
<programlisting>#ZONE HOST(S) OPTIONS
|
|
vpn1 ppp+:192.168.1.0/24
|
|
vpn2 ppp+:192.168.2.0/24
|
|
vpn3 ppp+:192.168.3.0/24</programlisting>
|
|
|
|
<para>Your policies and rules can now be configured using separate
|
|
zones (vpn1, vpn2, and vpn3) for the three remote network.</para>
|
|
</section>
|
|
</section>
|
|
</section>
|
|
|
|
<section id="ServerBehind">
|
|
<title>PPTP Server Running Behind your Firewall</title>
|
|
|
|
<para>If you have a single external IP address, add the following to your
|
|
/etc/shorewall/rules file:</para>
|
|
|
|
<para><filename>/etc/shorewall/rules</filename>:</para>
|
|
|
|
<programlisting>#ACTION SOURCE DEST PROTO DEST PORT(S)
|
|
DNAT net loc:<emphasis><server address></emphasis> tcp 1723
|
|
DNAT net loc:<emphasis><server address></emphasis> 47</programlisting>
|
|
|
|
<para>If you have multiple external IP address and you want to forward a
|
|
single <<emphasis>external address</emphasis>>, add the following to
|
|
your /etc/shorewall/rules file:</para>
|
|
|
|
<para><filename>/etc/shorewall/rules</filename>:</para>
|
|
|
|
<programlisting>#ACTION SOURCE DEST PROTO DEST PORT(S) SOURCE ORIGINAL
|
|
# PORT(S) DEST
|
|
DNAT net loc:<emphasis><server address></emphasis> tcp 1723 - <emphasis><external address></emphasis>
|
|
DNAT net loc:<emphasis><server address></emphasis> 47 - - <emphasis><external address></emphasis></programlisting>
|
|
|
|
<para>You will also want to add this entry to your
|
|
<filename>/etc/shorewall/masq</filename> file:</para>
|
|
|
|
<programlisting>#INTERFACE SUBNET ADDRESS PROTO
|
|
<<emphasis>external interface</emphasis>> <<emphasis>server address</emphasis>> <<emphasis>external address</emphasis>> 47</programlisting>
|
|
|
|
<important>
|
|
<para>Be sure that the above entry comes <emphasis
|
|
role="bold">before</emphasis> any other entry that might match the
|
|
server's address.</para>
|
|
</important>
|
|
</section>
|
|
|
|
<section id="ClientsBehind">
|
|
<title>PPTP Clients Running Behind your Firewall</title>
|
|
|
|
<para>You shouldn't have to take any special action for this case unless
|
|
you wish to connect multiple clients to the same external server. In that
|
|
case, you must install the PPTP connection/tracking and NAT patch from
|
|
<ulink url="http://www.netfilter.org">Netfilter Patch-O-Mati</ulink>c
|
|
(some distributions are now shipping with this patch installed). I
|
|
recommend that you also add these four lines to your
|
|
/etc/shorewall/modules file:</para>
|
|
|
|
<programlisting>loadmodule ip_conntrack_proto_gre
|
|
loadmodule ip_conntrack_pptp
|
|
loadmodule ip_nat_pptp
|
|
loadmodule ip_nat_proto_gre</programlisting>
|
|
|
|
<para>For LEAF/Bering users, the 2.4.20 kernel as already been patched as
|
|
described at the URL above and the three modules are included in the
|
|
Bering 1.2 modules tarball.</para>
|
|
|
|
<warning>
|
|
<para>Installing the above modules will prevent any GRE tunnels that you
|
|
have from working correctly.</para>
|
|
</warning>
|
|
</section>
|
|
|
|
<section id="ClientFW">
|
|
<title>PPTP Client Running on your Firewall</title>
|
|
|
|
<para>The PPTP GNU/Linux client is available at <ulink
|
|
url="http://sourceforge.net/projects/pptpclient/">http://sourceforge.net/projects/pptpclient/</ulink>.
|
|
Rather than use the configuration script that comes with the client, I
|
|
built my own. I also build my own kernel <link linkend="PatchKernel">as
|
|
described above</link> rather than using the mppe package that is
|
|
available with the client. My /etc/ppp/options file is mostly unchanged
|
|
from what came with the client (see below).</para>
|
|
|
|
<para>The key elements of this setup are as follows:</para>
|
|
|
|
<orderedlist>
|
|
<listitem>
|
|
<para>Define a zone for the remote network accessed via PPTP.</para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para>Associate that zone with a ppp interface.</para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para>Define rules for PPTP traffic to/from the firewall.</para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para>Define rules for traffic two and from the remote zone.</para>
|
|
</listitem>
|
|
</orderedlist>
|
|
|
|
<para>Here are examples from one of my old setups:</para>
|
|
|
|
<para><filename>/etc/shorewall/zones</filename>:</para>
|
|
|
|
<programlisting>#ZONE DISPLAY COMMENTS
|
|
cpq Compaq Compaq Intranet</programlisting>
|
|
|
|
<para><filename>/etc/shorewall/interfaces</filename>:</para>
|
|
|
|
<programlisting>#ZONE INTERFACE BROADCAST OPTIONS
|
|
- ppp+</programlisting>
|
|
|
|
<para>/etc/shorewall/hosts:</para>
|
|
|
|
<programlisting>#ZONE HOST(S) OPTIONS
|
|
cpq ppp+:!192.168.1.0/24</programlisting>
|
|
|
|
<para><filename>/etc/shorewall/tunnels</filename>:</para>
|
|
|
|
<programlisting>#TYPE ZONE GATEWAY GATEWAY ZONE
|
|
pptpclient net 0.0.0.0/0</programlisting>
|
|
|
|
<para>I use the combination of interface and hosts file to define the
|
|
<quote>cpq</quote> zone because I also run a PPTP server on my firewall
|
|
(see above). Using this technique allows me to distinguish clients of my
|
|
own PPTP server from arbitrary hosts at Compaq; I assign addresses in
|
|
192.168.1.0/24 to my PPTP clients and Compaq doesn't use that RFC1918
|
|
Class C subnet.</para>
|
|
|
|
<para>I use this script in /etc/init.d to control the client. The reason
|
|
that I disable ECN when connecting is that the Compaq tunnel servers don't
|
|
do ECN yet and reject the initial TCP connection request if I enable ECN
|
|
:-(</para>
|
|
|
|
<programlisting>#!/bin/sh
|
|
#
|
|
# /etc/rc.d/init.d/pptp
|
|
#
|
|
# chkconfig: 5 60 85
|
|
# description: PPTP Link Control
|
|
#
|
|
NAME="Tandem"
|
|
ADDRESS=tunnel-tandem.compaq.com
|
|
USER='Tandem\tommy'
|
|
ECN=0
|
|
DEBUG=
|
|
|
|
start_pptp() {
|
|
echo $ECN > /proc/sys/net/ipv4/tcp_ecn
|
|
if /usr/sbin/pptp $ADDRESS user $USER noauth $DEBUG; then
|
|
touch /var/lock/subsys/pptp
|
|
echo "PPTP Connection to $NAME Started"
|
|
fi
|
|
}
|
|
|
|
stop_pptp() {
|
|
if killall /usr/sbin/pptp 2> /dev/null; then
|
|
echo "Stopped pptp"
|
|
else
|
|
rm -f /var/run/pptp/*
|
|
fi
|
|
|
|
# if killall pppd; then
|
|
# echo "Stopped pppd"
|
|
# fi
|
|
|
|
rm -f /var/lock/subsys/pptp
|
|
|
|
echo 1 > /proc/sys/net/ipv4/tcp_ecn
|
|
}
|
|
|
|
|
|
case "$1" in
|
|
start)
|
|
echo "Starting PPTP Connection to ${NAME}..."
|
|
start_pptp
|
|
;;
|
|
stop)
|
|
echo "Stopping $NAME PPTP Connection..."
|
|
stop_pptp
|
|
;;
|
|
restart)
|
|
echo "Restarting $NAME PPTP Connection..."
|
|
stop_pptp
|
|
start_pptp
|
|
;;
|
|
status)
|
|
ifconfig
|
|
;;
|
|
*)
|
|
echo "Usage: $0 {start|stop|restart|status}"
|
|
;;
|
|
esac</programlisting>
|
|
|
|
<para>Here's my /etc/ppp/options file:</para>
|
|
|
|
<programlisting>#
|
|
# Identify this connection
|
|
#
|
|
ipparam Compaq
|
|
#
|
|
# Lock the port
|
|
#
|
|
lock
|
|
#
|
|
# We don't need the tunnel server to authenticate itself
|
|
#
|
|
noauth
|
|
|
|
+chap
|
|
+chapms
|
|
+chapms-v2
|
|
|
|
multilink
|
|
mrru 1614
|
|
#
|
|
# Turn off transmission protocols we know won't be used
|
|
#
|
|
nobsdcomp
|
|
nodeflate
|
|
|
|
#
|
|
# We want MPPE
|
|
#
|
|
mppe-128
|
|
mppe-stateless
|
|
|
|
#
|
|
# We want a sane mtu/mru
|
|
#
|
|
mtu 1000
|
|
mru 1000
|
|
|
|
#
|
|
# Time this thing out of it goes poof
|
|
#
|
|
lcp-echo-failure 10
|
|
lcp-echo-interval 10</programlisting>
|
|
|
|
<para>My /etc/ppp/ip-up.local file sets up the routes that I need to route
|
|
Compaq traffic through the PPTP tunnel:</para>
|
|
|
|
<programlisting>#/bin/sh
|
|
|
|
case $6 in
|
|
Compaq)
|
|
route add -net 16.0.0.0 netmask 255.0.0.0 gw $5 $1
|
|
route add -net 130.252.0.0 netmask 255.255.0.0 gw $5 $1
|
|
route add -net 131.124.0.0 netmask 255.255.0.0 gw $5 $1
|
|
...
|
|
;;
|
|
esac</programlisting>
|
|
|
|
<para>Finally, I run the following script every five minutes under crond
|
|
to restart the tunnel if it fails:</para>
|
|
|
|
<programlisting>#!/bin/sh
|
|
restart_pptp() {
|
|
/sbin/service pptp stop
|
|
sleep 10
|
|
if /sbin/service pptp start; then
|
|
/usr/bin/logger "PPTP Restarted"
|
|
fi
|
|
}
|
|
|
|
if [ -n "`ps ax | grep /usr/sbin/pptp | grep -v grep`" ]; then
|
|
exit 0
|
|
fi
|
|
|
|
echo "Attempting to restart PPTP"
|
|
|
|
restart_pptp > /dev/null 2>&1 &</programlisting>
|
|
|
|
<para><ulink url="ftp://ftp.shorewall.net/pub/shorewall/misc/Vonau">Here's
|
|
a script and corresponding ip-up.local</ulink> from Jerry Vonau
|
|
<email>jvonau@home.com</email> that controls two PPTP connections.</para>
|
|
</section>
|
|
|
|
<section id="PPTP_ADSL">
|
|
<title>PPTP Client running on your Firewall with PPTP Server in an ADSL
|
|
Modem</title>
|
|
|
|
<para>Some ADSL systems in Europe (most notably in Austria and the
|
|
Netherlands) feature a PPTP server built into an ADSL
|
|
<quote>Modem</quote>. In this setup, an ethernet interface is dedicated to
|
|
supporting the PPTP tunnel between the firewall and the
|
|
<quote>Modem</quote> while the actual internet access is through PPTP
|
|
(interface ppp0). If you have this type of setup, you need to modify the
|
|
sample configuration that you downloaded as described in this section.
|
|
<emphasis role="bold">These changes are in addition to those described in
|
|
the <ulink url="shorewall_quickstart_guide.htm">QuickStart
|
|
Guides</ulink>.</emphasis></para>
|
|
|
|
<para>Lets assume the following:</para>
|
|
|
|
<itemizedlist>
|
|
<listitem>
|
|
<para>ADSL Modem connected through eth0</para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para>Modem IP address = 192.168.1.1</para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para>eth0 IP address = 192.168.1.2</para>
|
|
</listitem>
|
|
</itemizedlist>
|
|
|
|
<para>The changes you need to make are as follows:</para>
|
|
|
|
<orderedlist>
|
|
<listitem>
|
|
<para>Add this entry to /etc/shorewall/zones:</para>
|
|
|
|
<programlisting>#ZONE DISPLAY COMMENTS
|
|
modem Modem ADSL Modem</programlisting>
|
|
|
|
<para>That entry defines a new zone called <quote>modem</quote> which
|
|
will contain only your ADSL modem.</para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para>Add the following entry to /etc/shorewall/interfaces:</para>
|
|
|
|
<programlisting>#ZONE INTERFACE BROADCAST OPTIONS
|
|
modem eth0 192.168.1.255 dhcp</programlisting>
|
|
|
|
<para>You will of course modify the <quote>net</quote> entry in
|
|
/etc/shorewall/interfaces to specify <quote>ppp0</quote> as the
|
|
interface as described in the QuickStart Guide corresponding to your
|
|
setup.</para>
|
|
</listitem>
|
|
|
|
<listitem>
|
|
<para>Add the following to /etc/shorewall/tunnels:</para>
|
|
|
|
<programlisting>#TYPE ZONE GATEWAY GATEWAY ZONE
|
|
pptpclient modem 192.168.1.1</programlisting>
|
|
|
|
<para>That entry allows a PPTP tunnel to be established between your
|
|
Shorewall system and the PPTP server in the modem.</para>
|
|
</listitem>
|
|
</orderedlist>
|
|
</section>
|
|
</article> |