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< title > Shorewall PPTP< / title >
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< h1 align = "center" > < font color = "#FFFFFF" > PPTP< / font > < / h1 >
< / td >
< / tr >
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< p align = "left" > Shorewall easily supports PPTP in a number of configurations:< / p >
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< ul >
< li >
< a href = "#ServerFW" > PPTP Server running on your Firewall< / a > < / li >
< li >
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< a href = "#ServerBehind" > PPTP Server running behind your
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Firewall.< / a > < / li >
< li >
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< a href = "#ClientsBehind" > PPTP Clients running behind your
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Firewall.< / a > < / li >
< li >
< a href = "#ClientFW" > PPTP Client running on your Firewall.< / a > < / li >
< / ul >
< h2 align = "center" > < a name = "ServerFW" > < / a > 1. PPTP Server Running on your Firewall< / h2 >
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< p > 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.< / p >
< p > The steps involved are:< / p >
< ol >
< li > < a href = "#PatchPppd" > Patching and building pppd< / a > < / li >
< li > < a href = "#PatchKernel" > Patching and building your Kernel< / a > < / li >
< li > < a href = "#Samba" > Configuring Samba< / a > < / li >
< li > < a href = "#ConfigPppd" > Configuring pppd< / a > < / li >
< li > < a href = "#ConfigPptpd" > Configuring pptpd< / a > < / li >
< li > < a href = "#ConfigFw" > Configuring Shorewall< / a > < / li >
< / ol >
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< h3 > < a name = "PatchPppd" > < / a > Patching and Building pppd< / h3 >
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< p > 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 < a href = "ftp://ftp.samba.org/pub/ppp" > ftp://ftp.samba.org/pub/ppp< / a > .< / p >
< p > You will need the following patches:< / p >
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< ul >
< li >
< a href = "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< / a > < / li >
< li > < a href = "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< / a > < / li >
< / ul >
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< p > You may also want the following patch if you want to require remote hosts to
use encryption:< / p >
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< ul >
< li > < a href = "ftp://ftp.shorewall.net/pub/shorewall/pptp/require-mppe.diff" > ftp://ftp.shorewall.net/pub/shorewall/pptp/require-mppe.diff< / a > < / li >
< / ul >
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< p > 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):< / p >
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< ul >
< li > cd ppp-2.4.1< / li >
< li > patch -p1 < ../ppp-2.4.0-openssl-0.9.6-mppe.patch< / li >
< li > patch -p1 < ../ppp-2.4.1-MSCHAPv2-fix.patch< / li >
< li > (Optional) patch -p1 < ../require-mppe.diff< / li >
< li > ./configure< / li >
< li > make< / li >
< / ul >
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< p > You will need to install the resulting binary on your firewall system. To do
that, I NFS mount my source filesystem and use " make install" from the
ppp-2.4.1 directory.< / p >
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< h3 > < a name = "PatchKernel" > < / a > Patching and Building your Kernel< / h3 >
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< p > You will need one of the following patches depending on your kernel version:< / p >
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< ul >
< li >
< a href = "http://www.shorewall.net/pub/shorewall/pptp/linux-2.4.4-openssl-0.9.6a-mppe-patch.gz" > http://www.shorewall.net/pub/shorewall/pptp/linux-2.4.4-openssl-0.9.6a-mppe-patch.gz< / a > < / li >
< li >
< a href = "http://www.shorewall.net/pub/shorewall/pptp/linux-2.4.16-openssl-0.9.6b-mppe-patch.gz" > http://www.shorewall/net/pub/shorewall/pptp/linux-2.4.16-openssl-0.9.6b-mppe-patch.gz< / a > < / li >
< / ul >
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< p > Uncompress the patch into the same directory where your top-level kernel
source is located and:< / p >
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< ul >
< li > cd < your GNU/Linux source top-level directory> < / li >
< li > patch -p1 < ../linux-2.4.16-openssl-0.9.6b-mppe.patch< / li >
< / ul >
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< p > Now configure your kernel. Here is my ppp configuration:< / p >
< blockquote >
< p > < img border = "0" src = "images/ppp.jpg" width = "592" height = "734" > < / p >
< / blockquote >
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< h3 > < a name = "Samba" > < / a > Configuring Samba< / h3 >
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< p > 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:< / p >
< blockquote >
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< pre > [global]
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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
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printable = Yes< / pre >
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< / blockquote >
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< h3 > < a name = "ConfigPppd" > < / a > Configuring pppd< / h3 >
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< p > Here is a copy of my /etc/ppp/options.poptop file:< / p >
< blockquote >
< p > < font face = "Courier" size = "2" > ipparam PoPToP< br >
lock< br >
mtu 1490< br >
mru 1490< br >
ms-wins 192.168.1.3< br >
ms-dns 206.124.146.177< br >
multilink< br >
proxyarp< br >
auth< br >
+chap< br >
+chapms< br >
+chapms-v2< br >
ipcp-accept-local< br >
ipcp-accept-remote< br >
lcp-echo-failure 30< br >
lcp-echo-interval 5< br >
deflate 0< br >
mppe-128< br >
mppe-stateless< br >
require-mppe< br >
require-mppe-stateless< / font > < / p >
< / blockquote >
< p > Notes:< / p >
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< ul >
< li > Since the firewall itself is acting as a WINS server, I have included the
firewall's internal IP as the 'ms-wins' value.< / li >
< li > I have pointed the remote clients at my DNS server -- it has external
address 206.124.146.177.< / li >
< li > I am requiring 128-bit stateless compression (my kernel is built with the
'require-mppe.diff' patch mentioned above.< / li >
< / ul >
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< p > Here's my /etc/ppp/chap-secrets:< / p >
< blockquote >
< p > < font face = "Courier" size = "2" > Secrets for authentication using CHAP< br >
# client server secret
IP addresses< br >
CPQTDM\\TEastep * < shhhhhh>
192.168.1.7< br >
TEastep *
< shhhhhh> 192.168.1.7< / font > < / p >
< / blockquote >
< p > 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 as it has when it is in its docking
station.< / p >
< p > You will also want the following in /etc/modules.conf:< / p >
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< pre > alias ppp-compress-18 ppp_mppe
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alias ppp-compress-21 bsd_comp
alias ppp-compress-24 ppp_deflate
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alias ppp-compress-26 ppp_deflate< / pre >
< h3 > < a name = "ConfigPptpd" > < / a > Configuring pptpd< / h3 >
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< p > PoPTop (pptpd) is available from < a href = "http://poptop.lineo.com/" > http://poptop.lineo.com/< / a > .< / p >
< p > Here is a copy of my /etc/pptpd.conf file:< / p >
< blockquote >
< p > < font face = "Courier" size = "2" > option /etc/ppp/options.poptop< br >
speed 115200< br >
localip 192.168.1.254< br >
remoteip 192.168.1.33-38< / font > < / p >
< / blockquote >
< p > Notes:< / p >
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< ul >
< li > I specify the /etc/ppp/options.poptop file as my ppp options file (I have
several).< / li >
< li > The local IP is the same as my internal interface's (192.168.1.254).< / li >
< li > I have assigned a remote IP range that overlaps my local network. This,
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together with 'proxyarp' in my /etc/ppp/options.poptop file make the remote
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hosts look like they are part of the local subnetwork.< / li >
< / ul >
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< p > I use this file to start/stop pptpd -- I have this in /etc/init.d/pptpd:< / p >
< blockquote >
< p > < font face = "Courier" size = "2" > #!/bin/sh< br >
#< br >
# /etc/rc.d/init.d/pptpd< br >
#< br >
# chkconfig: 5 12 85< br >
# description: control pptp server< br >
#< br >
< br >
case "$1" in< br >
start)< br >
echo 1 > /proc/sys/net/ipv4/ip_forward< br >
modprobe ppp_async< br >
modprobe ppp_generic< br >
modprobe ppp_mppe< br >
modprobe slhc< br >
if /usr/local/sbin/pptpd; then< br >
touch /var/lock/subsys/pptpd< br >
fi< br >
;;< br >
stop)< br >
killall pptpd< br >
rm -f /var/lock/subsys/pptpd< br >
;;< br >
restart)< br >
killall pptpd< br >
if /usr/local/sbin/pptpd; then< br >
touch /var/lock/subsys/pptpd< br >
fi< br >
;;< br >
status)< br >
ifconfig< br >
;;< br >
*)< br >
echo "Usage: $0 {start|stop|restart|status}"< br >
;;< br >
esac< / font > < / p >
< / blockquote >
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< h3 > < a name = "ConfigFw" > < / a > Configuring Shorewall< / h3 >
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< p > I consider hosts connected to my PPTP server to be just like local systems.
My key Shorewall entries are:< / p >
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< h4 > /etc/shorewall/zones:< / h4 >
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< blockquote >
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< table border = "2" cellpadding = "2" style = "border-collapse: collapse" >
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< tr >
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< td > < b > ZONE< / b > < / td >
< td > < b > DISPLAY< / b > < / td >
< td > < b > COMMENTS< / b > < / td >
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< / tr >
< tr >
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< td > net< / td >
< td > Internet< / td >
< td > The Internet< / td >
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< / tr >
< tr >
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< td > loc< / td >
< td > Local< / td >
< td > My Local Network including remote PPTP clients< / td >
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< / tr >
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< / table >
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< / blockquote >
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< h4 > /etc/shorewall/interfaces:< / h4 >
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< blockquote >
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< table border = "2" cellpadding = "2" style = "border-collapse: collapse" >
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< tr >
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< td > < b > ZONE< / b > < / td >
< td > < b > INTERFACE< / b > < / td >
< td > < b > BROADCAST< / b > < / td >
< td > < b > OPTIONS< / b > < / td >
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< / tr >
< tr >
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< td > net< / td >
< td > eth0< / td >
< td > 206.124.146.255< / td >
< td > noping,norfc1918< / td >
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< / tr >
< tr >
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< td > loc< / td >
< td > eth2< / td >
< td > 192.168.1.255< / td >
< td > < / td >
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< / tr >
< tr >
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< td > -< / td >
< td > ppp+< / td >
< td > < / td >
< td > < / td >
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< / tr >
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< / table >
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< / blockquote >
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< h4 > /etc/shorewall/hosts:< / h4 >
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< blockquote >
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< table border = "2" cellpadding = "2" style = "border-collapse: collapse" >
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< tr >
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< td > < b > ZONE< / b > < / td >
< td > < b > HOST(S)< / b > < / td >
< td > < b > OPTIONS< / b > < / td >
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< / tr >
< tr >
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< td > loc< / td >
< td > eth2:192.168.1.0/24< / td >
< td > routestopped< / td >
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< / tr >
< tr >
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< td > loc< / td >
< td > ppp+:192.168.1.0/24< / td >
< td > < / td >
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< / tr >
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< / table >
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< / blockquote >
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< h4 > /etc/shorewall/policy:< / h4 >
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< blockquote >
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< table border = "2" cellpadding = "2" style = "border-collapse: collapse" >
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< tr >
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< td > < b > SOURCE< / b > < / td >
< td > < b > DEST< / b > < / td >
< td > < b > POLICY< / b > < / td >
< td > < b > LOG LEVEL< / b > < / td >
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< / tr >
< tr >
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< td > loc< / td >
< td > loc< / td >
< td > ACCEPT< / td >
< td > < / td >
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< / tr >
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< / table >
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< / blockquote >
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< h4 > /etc/shorewall/rules:< / h4 >
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< blockquote >
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< table border = "2" cellpadding = "2" style = "border-collapse: collapse" >
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< tr >
< font face = "Century Gothic, Arial, Helvetica" >
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< td > < b > ACTION< / b > < / td >
< td > < b > SOURCE< / b > < / td >
< td > < b > DEST< / b > < / td >
< td > < b >
PROTO< / b > < / td >
< td > < b > DEST< br >
PORT(S)< / b > < / td >
< td > < b > SOURCE< br >
PORT(S)< / b > < / td >
< td > < b > ORIGINAL< br >
DEST< / b > < / td >
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< / font >
< / tr >
< tr >
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< td > ACCEPT< / td >
< td > net< / td >
< td > fw< / td >
< td > tcp< / td >
< td > 1723< / td >
< td > < / td >
< td > < / td >
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< / tr >
< tr >
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< td > ACCEPT< / td >
< td > net< / td >
< td > fw< / td >
< td > 47< / td >
< td > -< / td >
< td > < / td >
< td > < / td >
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< / tr >
< tr >
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< td > ACCEPT< / td >
< td > fw< / td >
< td > net< / td >
< td > 47< / td >
< td > -< / td >
< td > < / td >
< td > < / td >
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< / tr >
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< / table >
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< / blockquote >
< p align = "left" > Note: I have multiple ppp interfaces on my firewall. If you
have a single ppp interface, you probably want:< / p >
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< h4 > /etc/shorewall/interfaces:< / h4 >
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< blockquote >
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< table border = "2" cellpadding = "2" style = "border-collapse: collapse" >
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< tr >
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< td > < b > ZONE< / b > < / td >
< td > < b > INTERFACE< / b > < / td >
< td > < b > BROADCAST< / b > < / td >
< td > < b > OPTIONS< / b > < / td >
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< / tr >
< tr >
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< td > net< / td >
< td > eth0< / td >
< td > 206.124.146.255< / td >
< td > noping,norfc1918< / td >
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< / tr >
< tr >
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< td > loc< / td >
< td > eth2< / td >
< td > 192.168.1.255< / td >
< td > < / td >
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< / tr >
< tr >
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< td > loc< / td >
< td > ppp0< / td >
< td > < / td >
< td > < / td >
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< / tr >
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< / table >
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< / blockquote >
< p align = "left" > and < u > < b > no< / b > < / u > entries in /etc/shorewall/hosts.< / p >
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< h2 align = "center" > < a name = "ServerBehind" > < / a > 2. PPTP Server Running Behind your Firewall< / h2 >
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< p > If you have a single external IP address, add the following to your
/etc/shorewall/rules file:< / p >
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< table border = "2" cellpadding = "2" style = "border-collapse: collapse" >
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< tr >
< font face = "Century Gothic, Arial, Helvetica" >
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< td > < b > ACTION< / b > < / td >
< td > < b > SOURCE< / b > < / td >
< td > < b > DEST< / b > < / td >
< td > < b >
PROTO< / b > < / td >
< td > < b > DEST< br >
PORT(S)< / b > < / td >
< td > < b > SOURCE< br >
PORT(S)< / b > < / td >
< td > < b > ORIGINAL< br >
DEST< / b > < / td >
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< / font >
< / tr >
< tr >
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< td > DNAT< / td >
< td > net< / td >
< td > loc:< i > < server address> < / i > < / td >
< td > tcp< / td >
< td > 1723< / td >
< td > < / td >
< td > < / td >
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< / tr >
< tr >
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< td > DNAT< / td >
< td > net< / td >
< td > loc:< i > < server address> < / i > < / td >
< td > 47< / td >
< td > -< / td >
< td > < / td >
< td > < / td >
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< / tr >
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< / table >
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< p > If you have multiple external IP address and you want to forward a single < i > < external
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address> , < / i > add the following to your /etc/shorewall/rules file:< p > < table border = "2" cellpadding = "2" style = "border-collapse: collapse" >
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< tr >
< font face = "Century Gothic, Arial, Helvetica" >
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< td > < b > ACTION< / b > < / td >
< td > < b > SOURCE< / b > < / td >
< td > < b > DEST< / b > < / td >
< td > < b >
PROTO< / b > < / td >
< td > < b > DEST< br >
PORT(S)< / b > < / td >
< td > < b > SOURCE< br >
PORT(S)< / b > < / td >
< td > < b > ORIGINAL< br >
DEST< / b > < / td >
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< / font >
< / tr >
< tr >
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< td > DNAT< / td >
< td > net< / td >
< td > loc:< i > < server address> < / i > < / td >
< td > tcp< / td >
< td > 1723< / td >
< td > -< / td >
< td > < i > < external address> < / i > < / td >
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< / tr >
< tr >
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< td > DNAT< / td >
< td > net< / td >
< td > loc:< i > < server address> < / i > < / td >
< td > 47< / td >
< td > -< / td >
< td > -< / td >
< td > < i > < external address> < / i > < / td >
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< / tr >
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< / table >
< h2 align = "center" > < a name = "ClientsBehind" > < / a > 3. PPTP Clients Running Behind your Firewall< / h2 >
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< p > 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 will
need to follow the instructions at < a href = "http://www.impsec.org/linux/masquerade/ip_masq_vpn.html" > http://www.impsec.org/linux/masquerade/ip_masq_vpn.html< / a > .
I recommend that you also add these two lines to your /etc/shorewall/modules
file:
< blockquote >
< p > loadmodule ip_conntrack_pptp< br >
loadmodule ip_nat_pptp
< / blockquote >
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< h2 align = "center" > < a name = "ClientFW" > < / a > 4. PPTP Client Running on your Firewall.< / h2 >
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< p align = "left" > The PPTP GNU/Linux client is available at < a href = "http://sourceforge.net/projects/pptpclient/" > http://sourceforge.net/projects/pptpclient/< / a > .
Rather than use the configuration script that comes with the client, I built my
own. I also build my own kernel < a href = "#PatchKernel" > as described above< / a >
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).< / p >
< p > The key elements of this setup are as follows:
< ol >
< li > Define a zone for the remote network accessed via PPTP.< / li >
< li > Associate that zone with a ppp interface.< / li >
< li > Define rules for PPTP traffic to/from the firewall.< / li >
< li > Define rules for traffic two and from the remote zone.< / li >
< / ol >
< p > Here are examples from my setup:< / p >
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< h4 > /etc/shorewall/zones< / h4 >
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< blockquote >
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< table border = "2" cellpadding = "2" style = "border-collapse: collapse" >
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< tr >
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< td > < b > ZONE< / b > < / td >
< td > < b > DISPLAY< / b > < / td >
< td > < b > COMMENTS< / b > < / td >
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< / tr >
< tr >
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< td > cpq< / td >
< td > Compaq< / td >
< td > Compaq Intranet< / td >
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< / tr >
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< / table >
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< / blockquote >
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< h4 > /etc/shorewall/interfaces< / h4 >
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< blockquote >
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< table border = "2" cellpadding = "2" style = "border-collapse: collapse" >
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< tr >
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< td > < b > ZONE< / b > < / td >
< td > < b > INTERFACE< / b > < / td >
< td > < b > BROADCAST< / b > < / td >
< td > < b > OPTIONS< / b > < / td >
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< / tr >
< tr >
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< td > -< / td >
< td > ppp+< / td >
< td > < / td >
< td > < / td >
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< / tr >
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< / table >
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< / blockquote >
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< h4 > /etc/shorewall/hosts< / h4 >
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< blockquote >
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< table border = "2" cellpadding = "2" style = "border-collapse: collapse" >
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< tr >
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< td > < b > ZONE< / b > < / td >
< td > < b > HOST(S)< / b > < / td >
< td > < b > OPTIONS< / b > < / td >
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< / tr >
< tr >
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< td > -< / td >
< td > ppp+:!192.168.1.0/24< / td >
< td > < / td >
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< / tr >
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< / table >
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< / blockquote >
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< h4 > /etc/shorewall/rules< / h4 >
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< blockquote >
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< table border = "2" cellpadding = "2" style = "border-collapse: collapse" >
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< tr >
< font face = "Century Gothic, Arial, Helvetica" >
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< td > < b > ACTION< / b > < / td >
< td > < b > SOURCE< / b > < / td >
< td > < b > DEST< / b > < / td >
< td > < b >
PROTO< / b > < / td >
< td > < b > DEST< br >
PORT(S)< / b > < / td >
< td > < b > SOURCE< br >
PORT(S)< / b > < / td >
< td > < b > ORIGINAL< br >
DEST< / b > < / td >
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< / font >
< / tr >
< tr >
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< td > ACCEPT< / td >
< td > fw< / td >
< td > net< / td >
< td > tcp< / td >
< td > 1723< / td >
< td > < / td >
< td > < / td >
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< / tr >
< tr >
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< td > ACCEPT< / td >
< td > fw< / td >
< td > net< / td >
< td > 47< / td >
< td > -< / td >
< td > < / td >
< td > < / td >
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< / tr >
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< / table >
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< / blockquote >
< p > I use the combination of interface and hosts file to define the 'cpq' 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.
< p > 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 :-(
< blockquote >
< p > < font face = "Courier" size = "2" > #!/bin/sh< br >
#< br >
# /etc/rc.d/init.d/pptp< br >
#< br >
# chkconfig: 5 60 85< br >
# description: PPTP Link Control< br >
#< br >
NAME=" Tandem" < br >
ADDRESS=tunnel-tandem.compaq.com< br >
USER='Tandem\tommy'< br >
ECN=0< br >
DEBUG=< br >
< br >
start_pptp() {< br >
echo $ECN > /proc/sys/net/ipv4/tcp_ecn< br >
if /usr/sbin/pptp $ADDRESS user $USER noauth $DEBUG; then< br >
touch /var/lock/subsys/pptp< br >
echo "PPTP Connection to $NAME Started"< br >
fi< br >
}< br >
< br >
stop_pptp() {< br >
if killall /usr/sbin/pptp 2> /dev/null; then< br >
echo "Stopped pptp"< br >
else< br >
rm -f /var/run/pptp/*< br >
fi< br >
< br >
# if killall pppd; then< br >
# echo "Stopped pppd"< br >
# fi< br >
< br >
rm -f /var/lock/subsys/pptp< br >
< br >
echo 1 > /proc/sys/net/ipv4/tcp_ecn< br >
}< br >
< br >
< br >
case "$1" in< br >
start)< br >
echo "Starting PPTP Connection to ${NAME}..."< br >
start_pptp< br >
;;< br >
stop)< br >
echo "Stopping $NAME PPTP Connection..."< br >
stop_pptp< br >
;;< br >
restart)< br >
echo "Restarting $NAME PPTP Connection..."< br >
stop_pptp< br >
start_pptp< br >
;;< br >
status)< br >
ifconfig< br >
;;< br >
*)< br >
echo "Usage: $0 {start|stop|restart|status}"< br >
;;< br >
esac< br >
< / font >
< / blockquote >
< p > Here's my /etc/ppp/options file:
< blockquote >
< p > < font face = "Courier" size = "2" > #< br >
# Identify this connection< br >
#< br >
ipparam Compaq< br >
#< br >
# Lock the port< br >
#< br >
lock< br >
#< br >
# We don't need the tunnel server to authenticate itself< br >
#< br >
noauth< br >
< br >
+chap< br >
+chapms< br >
+chapms-v2< br >
< br >
multilink< br >
mrru 1614< br >
#< br >
# Turn off transmission protocols we know won't be used< br >
#< br >
nobsdcomp< br >
nodeflate< br >
< br >
#< br >
# We want MPPE< br >
#< br >
mppe-128< br >
mppe-stateless< br >
< br >
#< br >
# We want a sane mtu/mru< br >
#< br >
mtu 1000< br >
mru 1000< br >
< br >
#< br >
# Time this thing out of it goes poof< br >
#< br >
lcp-echo-failure 10< br >
lcp-echo-interval 10< / font >
< / blockquote >
< p > My /etc/ppp/ip-up.local file sets up the routes that I need to route Compaq
traffic through the PPTP tunnel:
< blockquote >
< p > < font face = "Courier" size = "2" > #/bin/sh< br >
< br >
case $6 in< br >
Compaq)< br >
route add -net 16.0.0.0 netmask 255.0.0.0 gw $5 $1< br >
route add -net 130.252.0.0 netmask 255.255.0.0 gw $5 $1< br >
route add -net 131.124.0.0 netmask 255.255.0.0 gw $5 $1< br >
...< br >
;;< br >
esac< / font > < / blockquote >
< p > Finally, I run the following script every five minutes under crond to
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restart the tunnel if it fails:< pre > #!/bin/sh
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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 &
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< / pre >
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< p > < a href = "ftp://ftp.shorewall.net/pub/shorewall/misc/Vonau" > Here's a script
and corresponding ip-up.local < / a > from < a href = "mailto:jvonau@home.com" > Jerry
Vonau < / a > that controls two PPTP connections.< / p >
< p > < font size = "2" > Last modified 7/11/2002 - < a href = "support.htm" > Tom
Eastep< / a > < / font > < p > < font face = "Trebuchet MS" > < a href = "copyright.htm" >
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< font size = "2" > Copyright< / font > <20> < font size = "2" > 2001, 2002 Thomas M. Eastep.< / font > < / a > < / font > < / body > < / html >
