OpenVPN Access Control: Difference between revisions

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</ul>
</ul>


If You have trouble seeing any of the settings, be sure to enable "'''Advanced mode'''"
[[File:Networking rutos manual webui basic advanced mode 75.gif|none|border|center|class=tlt-border]]
=Topology=
=Topology=


[[File:OpenVPN Topology v4.png|none|border|left|class=tlt-border|1000x1000px]]
[[File:OpenVPN Topology v1.png|border|center|class=tlt-border]]




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<li> Client 3 VPN tunnel address - 10.0.0.14, LAN device address - 192.168.30.178</li>
<li> Client 3 VPN tunnel address - 10.0.0.14, LAN device address - 192.168.30.178</li>
</ul>
</ul>
=Generating certificates for an OpenVPN server=
=Generating certificates for an OpenVPN server=


Navigate to '''System → Administration → Certificates → Generate Certificate'''
Navigate to '''System → Administration → Certificates'''


Generate 2 certificates. Recommended key size is at least '''2048 bits''' for security reasons:
&emsp; 1. Generate 2 certificates . Recommended key size is at least '''2048 bits''' for security reasons:


&emsp;1. CA
&emsp;&emsp; 1.1. CA


&emsp;2. Server
&emsp;&emsp; 1.2 Server


In Certificate Manager download Server certificate.
&emsp; 2.In Certificate Manager download Server certificate


[[File:Certificate download v4.png|none|border|left|class=tlt-border|1100x1100px]]
There are multiple methods of how certificates could be generated, you could follow this tutorial instead:
[[How to generate TLS certificates (Windows)?]]


For any OpenVPN clients, You will need to generate “'''Client'''” certificates, download the certificate and key, and send them to the client
[[File:Certificate download v3.png|none|border|left|class=tlt-border]]
 
For any OpenVPN clients, You will need to generate “Client” certificates, download certificate and key, and send them to the client


There are multiple methods of how certificates could be generated, you could follow this tutorial instead:
[[How to generate TLS certificates (Windows)?]]
=Creating an OpenVPN server=
=Creating an OpenVPN server=


Navigate to '''Services -> VPN -> OpenVPN'''. Add a new OpenVPN instance with a '''Server role''' with these settings:
Connect to WebUI and enable Advanced mode
 
[[File:Networking rutos manual webui basic advanced mode 75.gif|none|border|center|class=tlt-border]]
 
Navigate to '''Services -> VPN -> OpenVPN'''
 
&emsp; 1. Add a new OpenVPN instance with a Server role
 
&emsp; 2. Create an OpenVPN server with these settings




[[File:OpenVPN server settings v3.png|none|border|left|class=tlt-border]]
[[File:OpenVPN server settings v3.png|none|border|left|class=tlt-border]]


1 - <b>Client to client</b> – disabled
1) Client to client – disabled
 
2) Virtual network IP address – 10.0.0.0


2 - <b>Virtual network IP address</b> 10.0.0.0
3) Virtual network netmask 255.255.255.224


3 - <b>Virtual network netmask</b> – 255.255.255.224
4) Certificate files from device - on


4 - <b>Certificate files from device</b> - on


Press '''"Save & Apply"''', enable OpenVPN server and check if the server is online


Press '''"Save & Apply"''', enable OpenVPN server and check if the server is online.
[[File:OpenVPN server is online v2.png|none|border|left|class=tlt-border]]


[[File:OpenVPN server is online v3.png|none|border|left|class=tlt-border|1100x1100px]]
=Connecting clients to the OpenVPN server=
=Connecting clients to the OpenVPN server=


Navigate to '''Services -> VPN -> OpenVPN'''. Add a new OpenVPN instance with a '''Client role''' with these settings:
Navigate to '''Services -> VPN -> OpenVPN'''
 
&emsp; 1. Add a new OpenVPN instance with a Client role
 
&emsp; 2. Create an OpenVPN client with these settings


[[File:OpenVPN Client1 v3.png|none|border|center|class=tlt-border]]
[[File:OpenVPN Client1 v3.png|none|border|center|class=tlt-border]]


&emsp;&emsp; 1 - '''Remote host/IP address''' - Public IP of the OpenVPN server's router


&emsp;&emsp; 2 - '''Remote network IP address''' - 10.0.0.0
&emsp;&emsp; 1) Remote host/IP address - Public IP of the OpenVPN server's router
 
&emsp;&emsp; 2) Remote network IP address - 10.0.0.0


&emsp;&emsp; 3 - '''Remote network netmask''' - 255.255.255.224
&emsp;&emsp; 3) Remote network netmask - 255.255.255.224


&emsp;&emsp; 4 - '''Add the certificates from the OpenVPN server''' - Certificate Authority, Client certificate, and Client key which we downloaded in the Certificate Generation step.
&emsp;&emsp; 4) Add the certificates from the OpenVPN server - Certificate Authority, Client certificate, and Client key which we downloaded in the Certificate Generation step




Press "'''Save & Apply'''", enable OpenVPN client, and check if the connection is made
&emsp; 4. Press "Save & Apply", enable OpenVPN client and check if the connection is made


[[File:OpenVPN Client1 connected v2.png|none|border|left|class=tlt-border|1100x1100px]]
[[File:OpenVPN Client1 connected v2.png|none|border|left|class=tlt-border]]
 
Repeat this step for as many clients as You need. For this example, we will have 3 clients


Repeat this step for as many clients as You need. For this example, we will have 3 clients.
=Client to Client LAN network communication=
=Client to Client LAN network communication=
==TLS Clients==
==TLS Clients==


On the OpenVPN server router, navigate to '''Services -> VPN -> OpenVPN''', Press "'''Edit'''" on the server, scroll down and add '''TLS clients''' which LAN address You want to have access to, in our case, we add all 3 clients:
&emsp; 1. On the OpenVPN server router, navigate to '''Services -> VPN -> OpenVPN''', Press "'''Edit'''" on the server, scroll down and add TLS clients and add clients which LAN address You want to have access to, in our case, we add all 3 clients
===TLS Client 1===
 
----
[[File:TLS Client1 v3.png|none|border|left|class=tlt-border]]
[[File:TLS Client1 v3.png|none|border|left|class=tlt-border]]
===TLS Client 2===
----
[[File:TLS Client2 v3.png|none|border|left|class=tlt-border]]
[[File:TLS Client2 v3.png|none|border|left|class=tlt-border]]
===TLS Client 3===
----
[[File:TLS Client3 v3.png|none|border|left|class=tlt-border]]
[[File:TLS Client3 v3.png|none|border|left|class=tlt-border]]


<ul>
<ul>
<li>'''Common name''' - common name of the certificate which was generated previously</li>
<li>Common name - common name of the certificate which was generated previously</li>
<li>'''Virtual local endpoint''' - client’s local address in the virtual network</li>
<li>Virtual local endpoint - client’s local address in the virtual network</li>
<li>'''Virtual remote endpoint''' - client’s remote address in the virtual network</li>
<li>Virtual remote endpoint - client’s remote address in the virtual network</li>
<li>'''Private network''' - client's LAN subnet</li>
<li>Private network - client's LAN subnet</li>
<li>'''Covered network''' - Which LAN subnet should clients be able to communicate with in the OpenVPN server</li>
<li>Covered network - Which LAN subnet should clients be able to communicate with in the OpenVPN server</li>
</ul>
</ul>
==Firewall Zones==
==Firewall Zones==


This step should be done on OpenVPN '''server and all clients''' that want their LAN subnets be accessible and to access other client's LAN subnets.
This step should be done on OpenVPN server and all clients that want their LAN subnets be accessible and to access other client's LAN subnets
 
&emsp; Navigate to '''Network -> Firewall -> General settings -> Zones''' and set OpenVPN zone to forward traffic to LAN
 
[[File:OpenVPN to LAN zone forward.png|none|border|left|class=tlt-border]]
 


Navigate to '''Network -> Firewall -> General settings -> Zones''' and set OpenVPN zone to forward traffic to LAN.


[[File:OpenVPN to LAN zone forward v2.png|none|border|left|class=tlt-border|1100x1100px]]
==Routes to LAN subnets==
==Routes to LAN subnets==


Create a route to other client LAN networks using WebUI. This step should be done on '''all clients''' that want their LAN subnets be accessible and to access other client's LAN subnets.
Create a route to other client LAN networks using WebUI. This step should be done on all <b>clients</b> that want their LAN subnets be accessible and to access other client's LAN subnets
 


Navigate to '''Services -> VPN -> OpenVPN''' press '''"Edit"''' on the OpenVPN client and add routes to other client LAN subnets. In this image, we are editing Client 1's configuration's extra options, to add routes to <b>Client 2's (192.168.20.0/24)</b> and <b>Client 3's (192.168.30.0/24)</b> LAN subnets.
&emsp; 1. Navigate to '''Services -> VPN -> OpenVPN''' press '''"Edit"''' on the OpenVPN client and add routes to other client LAN subnets. In this image, we are editing Client 1's configuration's extra options, to add routes to <b>Client 2's (192.168.20.0/24)</b> and <b>Client 3's (192.168.30.0/24)</b> LAN subnets.


(In some cases, pushing routes to LAN addresses from the OpenVPN server to clients, breaks routing on the clients, so doing it from the client side is safer, but more time consuming)
[[File:OpenVPN client routes.png|none|border|left|class=tlt-border]]


[[File:OpenVPN client routes v2.png|none|border|left|class=tlt-border]]
=Controlling access with firewall=
=Controlling access with firewall=


Navigate to '''Network -> Firewall -> Access Control''' and create a new deny rule. In this example, we are denying Client 3 from accessing any other clients and their LAN networks.
Navigate to '''Network -> Firewall -> Access Control''' and create a new deny rule. In this example, we are denying Client 3 from accessing any other clients and their LAN networks


[[File:Deny Client3 rule v2.png|none|border|left|class=tlt-border]]
[[File:Deny Client3 rule v2.png|none|border|left|class=tlt-border]]




&emsp;&emsp; 1 - '''Protocol''' - All protocols
&emsp;&emsp; 1. Protocol - All protocols


&emsp;&emsp; 2 - '''Source zone''' - OpenVPN
&emsp;&emsp; 2. Source zone - OpenVPN


&emsp;&emsp; 3 - '''Source IP''' - OpenVPN remote IP and LAN subnet of client 3
&emsp;&emsp; 3. Source IP - OpenVPN remote IP and LAN subnet of client 3


&emsp;&emsp; 4 - '''Destination zone''' - OpenVPN
&emsp;&emsp; 4. Destination zone - OpenVPN


&emsp;&emsp; 5 - '''Destination address''' - other client OpenVPN remote endpoints and LAN subnets
&emsp;&emsp; 5. Destination address - other client OpenVPN remote endpoints and LAN subnets


&emsp;&emsp; 6 - '''Action''' - Deny
&emsp;&emsp; 6. Action - Deny




This rule will deny all traffic from Client 3 to other clients, but will not interact with traffic, if it's destination is OpenVPN server or it's LAN subnet.
This rule will deny all traffic from Client 3 to other clients, but will not interact with traffic, if it's destination is OpenVPN server or it's LAN subnet
=Testing the setup=


If You have followed the steps correctly, configuration should be finished. These should be the results that You will be getting:


=Testing the setup=


Client 1 to Client 2
Client 1 to Client 2

Revision as of 15:45, 29 March 2024

The information on this page is updated in accordance with the 00.07.06.6 firmware version .

Introduction

Normally, OpenVPN Client access is controlled by enabling or disabling the Client to Client button in OpenVPN Servers configuration, however, at times, more granular control is required. In this example, we will configure an OpenVPN server with 3 Clients:

    1. Client 1 will be able to communicate with Client 2 and OpenVPN server
    2. Client 2 will be able to communicate with Client 1 and OpenVPN server
    3. Client 3 will only be able to communicate with OpenVPN server, but not with any of other clients

Topology


  • OpenVPN server tunnel address - 10.0.0.1, OpenVPN subnet - 10.0.0.0/27, LAN device address - 192.168.5.114
  • Client 1 VPN tunnel address - 10.0.0.6, LAN device address - 192.168.10.216
  • Client 2 VPN tunnel address - 10.0.0.10, LAN device address - 192.168.20.193
  • Client 3 VPN tunnel address - 10.0.0.14, LAN device address - 192.168.30.178

Generating certificates for an OpenVPN server

Navigate to System → Administration → Certificates

  1. Generate 2 certificates . Recommended key size is at least 2048 bits for security reasons:

   1.1. CA

   1.2 Server

  2.In Certificate Manager download Server certificate

There are multiple methods of how certificates could be generated, you could follow this tutorial instead: How to generate TLS certificates (Windows)?

For any OpenVPN clients, You will need to generate “Client” certificates, download certificate and key, and send them to the client

Creating an OpenVPN server

Connect to WebUI and enable Advanced mode

Navigate to Services -> VPN -> OpenVPN

  1. Add a new OpenVPN instance with a Server role

  2. Create an OpenVPN server with these settings


1) Client to client – disabled

2) Virtual network IP address – 10.0.0.0

3) Virtual network netmask – 255.255.255.224

4) Certificate files from device - on


Press "Save & Apply", enable OpenVPN server and check if the server is online

Connecting clients to the OpenVPN server

Navigate to Services -> VPN -> OpenVPN

  1. Add a new OpenVPN instance with a Client role

  2. Create an OpenVPN client with these settings


   1) Remote host/IP address - Public IP of the OpenVPN server's router

   2) Remote network IP address - 10.0.0.0

   3) Remote network netmask - 255.255.255.224

   4) Add the certificates from the OpenVPN server - Certificate Authority, Client certificate, and Client key which we downloaded in the Certificate Generation step


  4. Press "Save & Apply", enable OpenVPN client and check if the connection is made

Repeat this step for as many clients as You need. For this example, we will have 3 clients

Client to Client LAN network communication

TLS Clients

  1. On the OpenVPN server router, navigate to Services -> VPN -> OpenVPN, Press "Edit" on the server, scroll down and add TLS clients and add clients which LAN address You want to have access to, in our case, we add all 3 clients


  • Common name - common name of the certificate which was generated previously
  • Virtual local endpoint - client’s local address in the virtual network
  • Virtual remote endpoint - client’s remote address in the virtual network
  • Private network - client's LAN subnet
  • Covered network - Which LAN subnet should clients be able to communicate with in the OpenVPN server

Firewall Zones

This step should be done on OpenVPN server and all clients that want their LAN subnets be accessible and to access other client's LAN subnets

  Navigate to Network -> Firewall -> General settings -> Zones and set OpenVPN zone to forward traffic to LAN


Routes to LAN subnets

Create a route to other client LAN networks using WebUI. This step should be done on all clients that want their LAN subnets be accessible and to access other client's LAN subnets

  1. Navigate to Services -> VPN -> OpenVPN press "Edit" on the OpenVPN client and add routes to other client LAN subnets. In this image, we are editing Client 1's configuration's extra options, to add routes to Client 2's (192.168.20.0/24) and Client 3's (192.168.30.0/24) LAN subnets.

Controlling access with firewall

Navigate to Network -> Firewall -> Access Control and create a new deny rule. In this example, we are denying Client 3 from accessing any other clients and their LAN networks


   1. Protocol - All protocols

   2. Source zone - OpenVPN

   3. Source IP - OpenVPN remote IP and LAN subnet of client 3

   4. Destination zone - OpenVPN

   5. Destination address - other client OpenVPN remote endpoints and LAN subnets

   6. Action - Deny


This rule will deny all traffic from Client 3 to other clients, but will not interact with traffic, if it's destination is OpenVPN server or it's LAN subnet


Testing the setup

Client 1 to Client 2

Pinging 192.168.20.193 from 192.168.10.216 with 32 bytes of data:
Reply from 192.168.20.194: bytes=32 time=172ms TTL=125
Reply from 192.168.20.194: bytes=32 time=114ms TTL=125
Reply from 192.168.20.194: bytes=32 time=113ms TTL=125
Reply from 192.168.20.194: bytes=32 time=294ms TTL=125

Client 1 to Client 3

Pinging 192.168.30.178 from 192.168.10.216 with 32 bytes of data:
Request timed out.
Request timed out.
Request timed out.
Request timed out.

Client 2 to Client 1

Pinging 192.168.10.216 from 192.168.20.193 with 32 bytes of data:
Reply from 192.168.10.216: bytes=32 time=185ms TTL=125
Reply from 192.168.10.216: bytes=32 time=123ms TTL=125
Reply from 192.168.10.216: bytes=32 time=227ms TTL=125
Reply from 192.168.10.216: bytes=32 time=189ms TTL=125

Client 2 to Client 3

Pinging 192.168.30.178 from 192.168.20.193 with 32 bytes of data:
Request timed out.
Request timed out.
Request timed out.
Request timed out.

Client 3 to Client 1

Pinging 192.168.10.216 from 192.168.30.178 with 32 bytes of data:
Request timed out.
Request timed out.
Request timed out.
Request timed out.

Client 3 to Client 2

Pinging 192.168.20.193 from 192.168.30.178 with 32 bytes of data:
Request timed out.
Request timed out.
Request timed out.
Request timed out.

And server can reach all of the clients and their LAN subnets

Pinging 192.168.10.216 from 192.168.5.114 with 32 bytes of data:
Reply from 192.168.5.114: bytes=32 time=264ms TTL=62
Reply from 192.168.5.114: bytes=32 time=138ms TTL=62
Reply from 192.168.5.114: bytes=32 time=81ms TTL=62
Reply from 192.168.5.114: bytes=32 time=107ms TTL=62

Pinging 192.168.20.193 from 192.168.5.114 with 32 bytes of data:
Reply from 192.168.5.114: bytes=32 time=61ms TTL=62
Reply from 192.168.5.114: bytes=32 time=376ms TTL=62
Reply from 192.168.5.114: bytes=32 time=132ms TTL=62
Reply from 192.168.5.114: bytes=32 time=232ms TTL=62

Pinging 192.168.30.178 from 192.168.5.114 with 32 bytes of data:
Reply from 192.168.5.114: bytes=32 time=226ms TTL=62
Reply from 192.168.5.114: bytes=32 time=327ms TTL=62
Reply from 192.168.5.114: bytes=32 time=111ms TTL=62
Reply from 192.168.5.114: bytes=32 time=80ms TTL=62


See also


External links

https://openvpn.net/index.php/open-source/documentation/howto.html - some additional information on OpenVPN