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Line 1: + + − ='''IPSec OpenSwan VPN to connect Servers HOWTO'''= + − '''Author/Contribitor: John Crisp'''+ + + − + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + − Summary: The purpose of this howto is to guide you through the procedure to connect servers using OpenSwan VPN to connect via IPSEC.+ − I actually use it so my Draytek routers can connect to my online Koozali SME VPS machine+ + − This works on Koozali SME v8 and v9 with the unit in server-gateway mode.+ + − On the online VPS it has a 'dummy' internal network adaptor but works fine with this.+ − ==Setup== − ===SME Server 9.0=== − yum install openswan − ===SME Server 8.1 − On v8 you need to find the following package, or newer : − openswan-2.6.38-1.x86_64.rpm+ − You can grab a copy here :+ − http://www.reetspetit.com/smeserver/5/repoview/index.html+ − I can't remember if I built that myself or got it somewhere as it seems quite elusive. If I can find the source I will build a src rpm.+ − Then + − yum localinstall openswan-2.6.38-1.x86_64.rpm+ + + + + + + + + + + − You will need a link in etc/rc.d/rc7.d so the service starts : − S99ipsec -> /etc/rc.d/init.d/e-smith-service+ + − Alternatively to do it the Koozali SME way :+ − Create db entry:+ − db configuration set ipsec service status enabled+ − db configuration show ipsec+ − ipsec=service + + + + + + + − − ln -s /etc/rc.d/init.d/e-smith-service /etc/rc.d/rc7.d/S99ipsec − You can now enable and disble the service accordingly. + + + + + + + + + + + + + + + + − ===Firewall===+ − We need a new template fragment to allow ipsec through the firewall+ + − touch /etc/e-smith/templates-custom/etc/rc.d/init.d/masq/15AllowIPsec+ − Add the following code :+ + + + + + − # IPsec ports − /sbin/iptables -A INPUT -i $OUTERIF -p udp --sport 500 --dport 500 -j ACCEPT + − /sbin/iptables -t mangle -A PREROUTING -i $OUTERIF -p 50 -j MARK --set-mark 1 − /sbin/iptables -A INPUT -i $OUTERIF -m mark --mark 1 -j ACCEPT − /sbin/iptables -A FORWARD -i $OUTERIF -m mark --mark 1 -j ACCEPT − /sbin/iptables -A INPUT -i $OUTERIF -m mark --mark 2 -j ACCEPT − /sbin/iptables -A FORWARD -i $OUTERIF -m mark --mark 2 -j ACCEPT − /sbin/iptables -t nat -I POSTROUTING -m policy --dir out --pol ipsec -j ACCEPT − expand-template /etc/rc.d/init.d/masq+ − service masq restart+ + + + + + + + + + − We also need to disable redirects.+ − I have the following code in a file called Disable_Redirects.sh and a link to it in /etc/rc.d/rc.local+ + + − #!/bin/bash+ − # For OpenSwan − # Disable send redirects − echo 0 > /proc/sys/net/ipv4/conf/all/send_redirects − echo 0 > /proc/sys/net/ipv4/conf/default/send_redirects − echo 0 > /proc/sys/net/ipv4/conf/eth0/send_redirects − echo 0 > /proc/sys/net/ipv4/conf/eth1/send_redirects − echo 0 > /proc/sys/net/ipv4/conf/lo/send_redirects − # echo 0 > /proc/sys/net/ipv4/conf/ppp0/send_redirects − # Disable accept redirects+ − echo 0 > /proc/sys/net/ipv4/conf/all/accept_redirects − echo 0 > /proc/sys/net/ipv4/conf/default/accept_redirects − echo 0 > /proc/sys/net/ipv4/conf/eth0/accept_redirects − echo 0 > /proc/sys/net/ipv4/conf/eth1/accept_redirects − echo 0 > /proc/sys/net/ipv4/conf/lo/accept_redirects − # echo 0 > /proc/sys/net/ipv4/conf/ppp0/accept_redirects + − ===OpenSwan Configuration===+ + + + + + + + + + + + + + + + + + + − Here is a sample of my /etc/ipsec.conf with some added notes.+ − LEFT side is your server. RIGHT side is your router.+ + + + − # /etc/ipsec.conf+ − # basic configuration − #auto = 'start' for both ways or 'add' for incoming only+ + + + + − version 2.0+ + − config setup+ − # Debug-logging controls: "none" for (almost) none, "all" for lots. − #klipsdebug=none − plutodebug=none − interfaces=%defaultroute − oe=no − protostack=netkey − syslog=syslog.debug − # syslog=syslog.warning − virtual_private=%v4:192.168.0.0/24, # Here you add the local/internal network of your server − nat_traversal=yes # if required - probably yes − # Connection settings+ − # Router to Server+ − conn draytek-wan1 # Your connection name − type=tunnel − authby=secret − auto=start # n.b. "auto = start" for ipsec to try and make a connection or "auto = add" to accept incoming − ikelifetime=28800s − keylife=3600s − left=%defaultroute − leftsourceip=192.168.98.1 # This is the IP address of your internal ethernet connection on your server − leftsubnet=192.168.98.0/24 # This is your local network on your server − pfs=yes # If require − dpdaction=restart − dpddelay=30 − dpdtimeout=10 − right=1.2.3.4 # This is the WAN IP address of your router that is connecting in − rightsubnet=192.168.0.0/24 # This is the local network behind the router at the far end − # More incoming connections here.....+ + − ===Passwords===+ − The following file needs to be looked after and should be set chmod 0600+ − # /etc/ipsec.secrets+ − # Format is − # Incoming_IP Local_IP: PSK "Your#Strong#Password" − 1.2.3.4 %any: PSK "Your#Strong#Password"+ − host.dnsalias.org %any: PSK "Your#Strong#Password" − 1.2.3.4 192.168.98.1: PSK "Your#Strong#Password" − %any 192.168.98.1: PSK "Your#Strong#Password" − A reboot should get everythign going.+ − Now set up your router. + − Create a new IPSEC VPN connection with the correct credentials and it shoudl connect up. − Check /var/log/secure for debug messages, and once you are happy, change the debug settings in ipsec.conf from debug to warning. + + + + + + + + + + + + + − + + + +
no edit summary
{{usefulnote}}
__TOC__
{{Warning box| Note that you should try and learn as much as you can about VPN, Ipsec, and Security in general before playing with this. You risk leaving your server exposed to the bad guys.
Whilst the contribs do their best to make sure there is a simple secure setup, I make no guarantees !
Where possible use RSA keys or certificates instead of passwords.
'''Revised: 15th Sept 2014'''
An alternative solution is https://wiki.contribs.org/OpenVPN_SiteToSite or https://wiki.contribs.org/OpenVPN_Bridge
Where possible avoid the use of PPTP as it was cracked a long time ago and is very easy to read
With IKE v2 it is possible to allow dial in clients.
For older dial clients you can also look at https://wiki.contribs.org/Smeserver-libreswan-xl2tpd
}}
=== Version ===
====Koozali SME v8====
<div style="background: #EFE9E9; border: 1px solid #AAA; padding: 5px; padding-bottom: 17px; margin: 5px; width: 97%">
<div style="float:right; background: #EFE9E9; border: 1px solid #AAA; padding: 5px; margin-left: 5px">
<div style="font-size: 80%"><b>Centos 5:</b></div>
<div style="font-size: 120%; font-weight: bold">[http://www.reetspetit.com/smeserver/5/repoview/openswan.html OpenSwan]</div> </div>
<div style="font-size: 120%; font-weight: bold;">openswan</div>
<div>Please use the version of openswan in the ReetP repo as below</div>
</div>
====Koozali SME v9====
{{ #smeversion: libreswan}}
{{ #smeversion: smeserver-libreswan}}
==About==
==Openswan==
[[File:openswan.jpg]]
[http://www.openswan.org Openswan] is a free implementation of IPsec & IKE for Linux. IPsec is the Internet Protocol Security and uses strong cryptography to provide both authentication and encryption services. These services allow you to build secure tunnels through untrusted networks. Everything passing through the untrusted net is encrypted by the ipsec gateway machine and decrypted by the gateway at the other end of the tunnel.The resulting tunnel is a virtual private network or VPN.
==Libreswan==
[http://www.libreswan.org Libreswan] is a free software implementation of the most widely supported and standarized VPN protocol based on ("IPsec") and the Internet Key Exchange ("IKE"). These standards are produced and maintained by the Internet Engineering Task Force ("IETF").
Note that Libreswan will become the default ipsec installation from CentOS 6.8
https://libreswan.org/wiki/HOWTO:_openswan_to_libreswan_migration
* Credits: John Crisp
* Discuss: This How-to can be discussed on the forums [http://forums.contribs.org/index.php/topic,51111.0.html '''here''']
==Installation==
= For Koozali SME10 =
For Koozali SME Server 10, the latest stable Libreswan can be found in the default repo's
Note that the contrib is currently in test so to install:
yum install smeserver-extrarepositories-libreswan -y
db yum_repositories setprop libreswan status enabled Priority 10
signal-event yum-modify
yum --enablerepo=smecontribs,smetest install smeserver-libreswan
Configuration options and notes are here (check the latest branch):
=For Koozali SME8=
For Koozali SME Server 8 you will need the [https://wiki.contribs.org/User:ReetP ReetP] repo to install openswan
{{:Reetspetit|transcludesection=SME9}}
signal-event yum-modify
Note that the contrib is currently in test so to install:
yum --enablerepo=smetest,reetp install smeserver-openswan
Configuration options and notes are here (check the latest branch):
https://github.com/reetp/smeserver-openswan
Please note that this version is no longer under development as SME v8 is EOL at the end of March 2017
It is possible to use Openswan on SME v9 but I do not have the time to maintain the contrib for both versions.
RedHat have swapped to using Libreswan as their default IPsec implementation.
= For Koozali SME9 =
For Koozali SME Server 9, the latest stable Libreswan can be found in the default repo's
Note that the contrib is currently in test so to install:
yum --enablerepo=smetest install smeserver-libreswan
Configuration options and notes are here (check the latest branch):
https://github.com/reetp/smeserver-libreswan
{{Note box|You can get the latest version of libreswan itself here }}
/sbin/e-smith/db yum_repositories set libreswan repository \
BaseURL https://download.libreswan.org/binaries/rhel/6/x86_64/ \
EnableGroups no \
GPGCheck yes \
GPGKey https://download.libreswan.org/binaries/RPM-GPG-KEY-libreswan \
Name LibreSwan \
Visible yes \
status disabled \
signal-event yum-modify
yum --enablerepo=libreswan install libreswan
<headertabs />
=IPSEC server to server configuration=
Libreswan/Openswan/IPSEC can be used to setup a secure and permanent VPN connection between a SME Server and another (local or remote) IPSEC enabled device such as a router.
Note - if you want to use with an online VPS set the server to server/gateway with a 'dummy' internal network adaptor.
===Passwords===
It is recommended to create a very strong random password and keep this safe. One way of generating and store a random strong password is explained [http://wiki.contribs.org/Useful_Commands#Generating_strong_random_password '''here''']
Alternatively see RSA key and Certificate sections below for much stronger passwords
===Setup PSK Passwords===
The contrib has a lot of configurable settings but with the defaults and a few details it should just work.
General settings and some defaults are stored in the main config DB
config show ipsec
Connection specific settings are stored in a separate DB
db ipsec_connections show
{{Note box|For ipsec_connections we use 'set' when we create a new connection. Thereafter you can modify it with setprop}}
{{Note box|Most people refer to East and West rather than Local and Remote. There is a very good reason for this if you start using RSA keys !}}
Server East - WAN IP 5.6.7.8 Local IP 192.168.20.1 Subnet 192.168.20.0/24
db ipsec_connections set MyEast ipsec status enabled leftsourceip 192.168.20.1 leftsubnet 192.168.20.0/24 right 1.2.3.4 rightsubnet 10.0.0.0/24 passwd MyPassWd
Server West- WAN IP 1.2.3.4 Local IP 10.0.0.1 Subnet 10.0.0.0/24
db ipsec_connections set MyWest ipsec status enabled leftsourceip 10.0.0.1 leftsubnet 10.0.0.0/24 right 5.6.7.8 rightsubnet 192.168.20.0/24 passwd MyPassWd
signal-event ipsec-update
===Setup RSA Keys===
For the better security it is recommended to use RSA keys.
There are notes on github as this can be quite lengthy
https://github.com/reetp/smeserver-libreswan/blob/master/IpsecSettings.txt
A basic ipsec_connections entry setup should look this - note it will need a matching setup at the other end):
MyEast=ipsec
leftsourceip=192.168.20.1
leftsubnet=192.168.20.0/24
right=1.2.3.4
rightsubnet=10.0.0.0/24
security=rsasig
leftid=East
rightid=West
leftrsasig=SomeLongPassFromEast
rightrsasig=SomeLongPasswordFromWest
status enabled
===Setup Certificates===
You can now use a CA and PKCS#12 certificates.
There are notes on github as this can be quite lengthy
https://github.com/reetp/smeserver-libreswan/blob/master/ipsec-certificate-notes.txt
A basic ipsec_connections entry setup should look this:
MyEast=ipsec
leftcert=LocalServer
leftsourceip=192.168.1.1
leftsubnet=192.168.1.0/24
right=5.6.7.8
rightcert=RemoteServer
rightsubnet=192.168.100.0/24
security=certs
status=enabled
status=enabled
===DB Keys===
There are a lot of keys involved in ipsec.
Where possible just use the minimum that you require depending on whether you want PSK password / RSA signature / Certificate security
There are notes on github as this can be quite lengthy
https://github.com/reetp/smeserver-libreswan/blob/master/IpsecSettings.txt
Here are the currently available settings and options:
====IPsec settings====
These settings are generic and can be overwritten on a per connection basis
config ipsec show
Only set with:
db configuration setprop ipsec $key $property
Setting status enabled/disabled will modify access to private/public
status: Default disabled | enabled
access: Default private | public
UDPPorts: Default 500,4500 | Variable
auto: Default start | add (do not use ondemand or ignore)
debug: none | all raw crypt parsing emitting control controlmore lifecycle dns dpd klips pfkey natt oppo oppoinfo whackwatch private
(all generates a LARGE amount of logging so use with care)
====General Settings====
Overall default settings - these can be in main config db or set per connection in db ipsec_connections
security: secret | rsasig | certs
ikelifetime: Default 3600s | Variable
salifetime: Default 28800s | Variable
dpdaction: Default restart | Variable
dpddelay: Default 30 | Variable
dpdtimeout: Default 10 | Variable
pfs: Default yes | Variable
connectiontype: Default secret | rassig, certificate
ike: Default aes-sha1 | Variable - see ipsec.conf readme file for more options - sample: aes256-sha2;dh14 or aes256-sha2;modp2048
ipsecversion: Default permit | Whether to allow ikev2 - also : insist/propose/yes/never/no
====Per connection settings====
{{Warning box|Automatically modified - do not change this
PreviousState: Denotes previous connection state
}}
Manual keys
db ipsec_connections show
db ipsec_connections setprop ConnectionName $key $property
iptype: Default Empty | stattodyn or dyntostat - are we a static host to dynamic client or vice versa ? - Only required for dynamic clients with static hosts
connectiontype: Default tunnel | transport/passthrough/drop/reject
leftrsasig: Default Empty | Your Local rsasignature key
rightrsasig: Default Empty | Your Remote rsasignature key
ipsecversion: Default permit | Whether to allow ikev2 - also : insist/propose/yes/never/no
ike: Default aes-sha1 | Variable - sample: aes256-sha2;dh14 or aes256-sha2;modp2048
phase2: Default aes-sha1 | Variable - sample: aes256-sha2;dh14 or aes256-sha2;modp2048
mtu: Default Empty | Variable
left: Default Empty | If Empty then %defaultroute is set. Can be local WAN IP
leftid: Default Empty | Variable
leftsourceip: Default Empty | This server local IP
leftsubnet: Default Empty | This server local subnet
right: Default Empty | Destination WAN IP
rightid: Default Empty | Variable
rightsubnet: Default Empty | Destination subnet
passwd: Default Empty | Variable
keyingtries: Default Empty | 0 is default - 'forever'
leftcert Default Empty | LeftCertName
rightcert Default Empty | RightCertName
For certificates - do not set or leave the following empty:
leftrsasig: Default Empty - system generates %cert
rightrsasig: Default Empty - system generates %cert
leftid: Default Empty - system generates %fromcert
rightid: Default Empty - system generates %fromcert
===Logs and Debug===
{{Warning box| If you are trying to connect Libreswan to other *swan versions using IPsec v2 you may see this in the logs
"failed to match authenticator"
which may cause link failures.
This seems to be an issue with some *swan versions - see this thread for more
https://lists.libreswan.org/pipermail/swan/2017/001956.html}}
The following will give you connection details.
ipsec whack --status
You should get this if the connection made : 'IPsec SA established'
The following check your configuration (may be some warnings - severity depends on what they are):
ipsec verify
If you modify a connection use
signal-event ipsec-update
For a restart of ipsec use
service ipsec restart
You may find masq needs a restart sometimes
/etc/init.d/masq restart
Check /var/log/iptables/current to see if packets are getting blocked.
For ipsec itself place to look is /var/log/pluto/pluto.log
If you need more debugging you can set plutodebug = all
If you need more debugging you can set plutodebug = all
=== Bug report ===
SME8 OpenSwan IPSEC is listed in the [http://bugs.contribs.org/enter_bug.cgi?product=SME%20Contribs&component=smeserver-openswan bugtracker contribs section].
Please report all bugs, new feature requests and documentation issues there.
{{#bugzilla:columns=id,product,version,status,summary |sort=id |order=desc |component=smeserver-openswan|noresultsmessage="No open bugs found."}}
SME9 LibreSwan IPSEC is listed in the [http://bugs.contribs.org/enter_bug.cgi?product=SME%20Contribs&component=smeserver-libreswan bugtracker contribs section].
Please report all bugs, new feature requests and documentation issues there.
{{#bugzilla:columns=id,product,version,status,summary |sort=id |order=desc |component=smeserver-libreswan|noresultsmessage="No open bugs found."}}
=Other articles in this category=
{{#ask: [[Category:VPN]]}}
[[Category:Contrib:HowTo]]
[[Category:Howto]]
[[Category:Contrib]]
[[Category:Administration:VPN]]
[[Category:Administration:VPN]]
[[Category:Security]]
[[Category:VPN]]