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==Summary==
{{Template: Networking_rutos_manual_vpn_rut2_rut9
 
<!------------------------DEVICE----------------------->
'''Virtual Private Network''' ('''VPN''') is a method for secure data transfer through unsafe public networks. This page is an overview of different types of VPNs that can be used with RUT routers.
| name   = RUT900
 
| series = RUT9
==OpenVPN==
}}
 
'''OpenVPN''' is an open-source software application that implements virtual private network (VPN) techniques for creating secure point-to-point or site-to-site connections in routed or bridged configurations and remote access facilities. This section is an overview of the OpenVPN section of RUTxxx routers. For a more in depth guide refer to our '''[[OpenVPN configuration examples]]''' page.
 
The default OpenVPN Configuration list is empty, so you have to define your own configuration to establish any sort of OpenVPN connection. OpenVPN configurations can have one of two roles: '''client''' or '''server'''. Let’s start with an OpenVPN client. To create it, enter the desired instance name in the '''New configuration name''' field, select the instance’s role from the '''Role''' list and press the '''Add New''' button.
 
[[Image:Services vpn openvpn creation.PNG]]
 
Once you’ve added a new OpenVPN instance there is no need to press the '''Save''' button, since the '''Add New''' button both creates and saves the new instance. By default the instance will be disabled and unconfigured. In order to establish an OpenVPN connection you must Enable your instance, enter an OpenVPN server address, choose an authentication method and a few other things, all of which can be configured in the '''Settings''' window, which can reached by pressing the '''Edit''' button next to your OpenVPN instance (as shown in the figure above).
 
===OpenVPN Client===
----
This section is overview of OpenVPN Client configuration.
 
[[File:Services vpn openvpn client v 2.png]]
 
The figure above is an example of a configured OpenVPN Client instance that uses the UDP protocol and TLS/Password authentication. Comprehensible explanations on how to configure each field are presented in the table below.
 
<table class="nd-mantable">
    <tr>
        <th>field name</th>
      <th>value</th>
      <th>description</th>
    </tr>
    <tr>
      <td>Enable</td>
      <td>yes {{!}} no; Default: '''no'''</td>
      <td>Enables the OpenVPN instance</td>
    </tr>
    <tr>
      <td>TUN/TAP</td>
      <td>TUN (tunnel) {{!}} TAP (bridged); Default: '''TUN (tunnel)'''</td>
      <td>OpenVPN interface type. '''TUN''' is most often in typical VPN connections, however, '''TAP''' is required in some Ethernet bridging configurations</td>
    </tr>
    <tr>
    <td>Protocol</td>
        <td>UDP {{!}} TCP; Default: '''UDP'''</td>
        <td>The transfer protocol used by the OpenVPN connection. '''TCP''' is connection oriented – once a connection is established, data can be sent bidirectionally. '''UDP''' is a simpler, connectionless Internet protocol. '''UDP''' is usually faster but '''TCP''' has more security features. Choose the connection protocol according to your needs.</td>
    </tr>
    <tr>
    <td>Port</td>
        <td>integer [0..65535]; Default: '''1194'''</td>
        <td>TCP/UDP Port number for both local and remote endpoints (make sure that the chosen port is allowed by firewall) </td>
    </tr>
    <tr>
      <td>LZO</td>
      <td>yes {{!}} no; Default: '''no'''</td>
      <td>With LZO compression, your VPN connection will generate less network traffic. However, enabling this causes a higher CPU load. Use it carefully with a high traffic rate or low CPU resources</td>
    </tr>
    <tr>
      <td>Encryption</td>
      <td>DES-CBC 64 {{!}} RC2-CBC 128 {{!}} DES-EDE-CBC 128 {{!}} DES-EDE3-CBC 192 {{!}} DESX-CBC 192 {{!}} BF-CBC 128 {{!}} RC2-40-CBC 40 {{!}} CAST5-CBC 128 {{!}} RC2-40CBC 40 {{!}} CAST5-CBC 128 {{!}} RC2-64-CBC 64{{!}} AES-128-CBC 128 {{!}} AES-192-CBC 192 {{!}} AES-256-CBC 256 {{!}} none; Default: '''BF-CBC 128'''</td>
      <td>Packet encryption algorithm</td>
    </tr>
    <tr>
    <td>Authentication</td>
        <td>TLS {{!}} Static Key {{!}} Password {{!}} TLS/Password; Default: '''TLS'''</td>
        <td>Authentication mode, used to secure data sessions.
'''Static key''' is a secret key used for server–client authentication.
 
'''TLS''' authentication mode uses X.509 type certificates:
 
'''Certificate Authority (CA)''', '''Client certificate''', '''Client key'''.
 
All mentioned certificates can be generated using OpenVPN or Open SSL utilities on any type of host machine.
 
'''Password''' is a simple username/password based authentication where the owner of the OpenVPN server provides the login data.
 
'''TLS/Password''' uses both TLS and Password authentication</td>
    </tr>
    <tr>
    <td>TLS cipher</td>
        <td>all {{!}} DHE+RSA {{!}} custom; Default: '''all'''</td>
        <td>Packet encryption algorithm cipher</td>
    </tr>
    <tr>
      <td>Remote host / IP address</td>
      <td>ip; Default: " "</td>
      <td>IP address or hostname of an OpenVPN server</td>
    </tr>
    <tr>
      <td>Resolve retry</td>
      <td>integer {{!}} infinite; Default: '''infinite'''</td>
      <td>Time in seconds to resolve server hostname periodically in case of first resolve failure before generating service exception</td>
    </tr>
    <tr>
    <td>Keep alive</td>
        <td>integer *space* integer; Default: " "</td>
        <td>Defines two time intervals: one is used to periodically send ICMP request to the OpenVPN server, the other defines a time window, which is used to restart the OpenVPN service, if no ICMP response is received during the window time slice.</td>
    </tr>
    <tr>
    <td>Remote network IP address</td>
        <td>ip; Default: " "</td>
        <td>LAN IP address of the remote network (server)</td>
    </tr>
    <tr>
    <td>Remote network IP netmask</td>
        <td>ip; Default: " "</td>
        <td>LAN IP subnet mask of the remote network (server)</td>
    </tr>
    <tr>
      <td>Username</td>
      <td>string; Default: " "</td>
      <td>User name used for authentication</td>
    </tr>
    <tr>
      <td>Password</td>
      <td>string; Default: " "</td>
      <td>Password name used for authentication</td>
    </tr>
    <tr>
    <td>Extra options</td>
        <td>string; Default: " "</td>
        <td>Extra options to be used by the OpenVPN instance</td>
    </tr>
    <tr>
    <td>HMAC authentication algorithm</td>
        <td>none {{!}} SHA1 {{!}} SHA256 {{!}} SHA384 {{!}} SHA512; Default: '''SHA1'''</td>
        <td>HMAC authentication algorithm type</td>
    </tr>
    <tr>
      <td>Additional HMAC authentication</td>
      <td>yes {{!}} no; Default: '''no'''</td>
      <td>An additional layer of HMAC authentication on top of the TLS control channel to protect against DoS attacks</td>
    </tr>
    <tr>
      <td>Certificate authority</td>
      <td>.ca file; Default: " "</td>
      <td>Certificate authority is an entity that issues digital certificates. A digital certificate certifies the ownership of a public key by the named subject of the certificate</td>
    </tr>
    <tr>
    <td>Client certificate</td>
        <td>.crt file; Default: " "</td>
        <td>Client certificate is a type of digital certificate that is used by client systems to make authenticated requests to a remote server. Client certificates play a key role in many mutual authentication designs, providing strong assurances of a requester's identity</td>
    </tr>
    <tr>
    <td>Client key</td>
        <td>.key file; Default: " "</td>
        <td>Authenticates the client to the server and establishes precisely who they are</td>
    </tr>
    <tr>
    <td>Private key decryption password (optional)</td>
        <td>string; Default: " "</td>
        <td>Decrypts server private key password. Use only if server's .key file is encrypted with a password</td>
    </tr>
</table>
 
After setting any of these parameters press the '''Save''' button or else the changes will not be applied. Some of the selected parameters will be shown in the configuration list table. You should also be aware of the fact that the router will launch a separate OpenVPN service for every configuration entry (if it is defined as active at the time, of course) so the router has the ability to act as server and client at the same time.
 
===OpenVPN Server===
----
This section is an overview of OpenVPN Server configuration.
 
[[Image:Services vpn openvpn server.PNG]]
 
The figure above is an example of a configured OpenVPN Server instance that uses the UDP protocol and TLS authentication. As you can see, the configuration is similar to OpenVPN Client but with a few key differences. Comprehensible explanations on each field are presented in the table below:
 
<table class="nd-mantable">
    <tr>
        <th>field name</th>
      <th>value</th>
      <th>description</th>
    </tr>
    <tr>
      <td>Enable</td>
      <td>yes {{!}} no; Default: '''no'''</td>
      <td>Enables the OpenVPN instance</td>
    </tr>
    <tr>
      <td>TUN/TAP</td>
      <td>TUN (tunnel) {{!}} TAP (bridged); Default: '''TUN (tunnel)'''</td>
      <td>OpenVPN interface type. '''TUN''' is most often in typical VPN connections, however, '''TAP''' is required in some Ethernet bridging configurations</td>
    </tr>
    <tr>
    <td>Protocol</td>
        <td>UDP {{!}} TCP; Default: '''UDP'''</td>
        <td>The transfer protocol used by the OpenVPN connection. '''TCP''' is connection oriented – once a connection is established, data can be sent bidirectionally. '''UDP''' is a simpler, connectionless Internet protocol. '''UDP''' is usually faster but '''TCP''' has more security features. Choose the connection protocol according to your needs.</td>
    </tr>
    <tr>
    <td>Port</td>
        <td>integer [0..65535]; Default: '''1194'''</td>
        <td>TCP/UDP Port number for both local and remote endpoints (make sure that the chosen port is allowed by firewall)</td>
    </tr>
    <tr>
      <td>LZO</td>
      <td>yes {{!}} no; Default: '''no'''</td>
      <td>With LZO compression, your VPN connection will generate less network traffic. However, enabling this causes a higher CPU load. Use it carefully with a high traffic rate or low CPU resources</td>
    </tr>
    <tr>
      <td>Encryption</td>
      <td>DES-CBC 64 {{!}} RC2-CBC 128 {{!}} DES-EDE-CBC 128 {{!}} DES-EDE3-CBC 192 {{!}} DESX-CBC 192 {{!}} BF-CBC 128 {{!}} RC2-40-CBC 40 {{!}} CAST5-CBC 128 {{!}} RC2-40CBC 40 {{!}} CAST5-CBC 128 {{!}} RC2-64-CBC 64{{!}} AES-128-CBC 128 {{!}} AES-192-CBC 192 {{!}} AES-256-CBC 256 {{!}} none; Default: '''BF-CBC 128'''</td>
      <td>Packet encryption algorithm</td>
    </tr>
    <tr>
    <td>Authentication</td>
        <td>TLS'''*''' {{!}} Static Key {{!}} Password {{!}} TLS/Password; Default: '''TLS'''</td>
        <td>Authentication mode, used to secure data sessions.
'''Static key''' is a secret key used for server–client authentication.
 
'''TLS''' authentication mode uses X.509 type certificates:
 
'''Certificate Authority (CA)''', '''Client certificate''', '''Client key'''.
 
All mentioned certificates can be generated using OpenVPN or Open SSL utilities on any type of host machine.
 
'''Password''' is a simple username/password based authentication where the owner of the OpenVPN server provides the login data.
 
'''TLS/Password''' uses both TLS and Password authentication</td>
    </tr>
    <tr>
    <td>TLS cipher</td>
        <td>all {{!}} DHE+RSA {{!}} custom; Default: '''all'''</td>
        <td>Packet encryption algorithm cipher</td>
    </tr>
    <tr>
      <td>Client to client</td>
      <td>yes {{!}} no; Default: '''no'''</td>
      <td>Enables client to client communication in the Virtual network. In order for Client to client to work, the TLS Clients section most be utilized</td>
    </tr>
    <tr>
      <td>Keep alive</td>
      <td>integer *space* integer; Default: " "</td>
      <td>efines two time intervals: one is used to periodically send ICMP request to the OpenVPN server, the other defines a time window, which is used to restart the OpenVPN service, if no ICMP response is received during the window time slice.<br>
'''Example:''' 10 60</td>
    </tr>
    <tr>
    <td>Virtual network IP address</td>
        <td>ip; Default: " "</td>
        <td>IP address of the Virtual network, e.g., '''10.0.8.0'''</td>
    </tr>
    <tr>
    <td>Virtual network IP netmask</td>
        <td>ip; Default: " "</td>
        <td>Subnet mask of the Virtual network</td>
    </tr>
    <tr>
      <td>Push option</td>
      <td>string; Default: " "</td>
      <td>Push options are a way to “push” user defined routes to connecting clients’ routing tables. In the example above, the server will push the route of 192.168.1.0 network with the 255.255.255.0 netmask to connecting clients. Therefore, the client will be able to reach devices in the 192.168.1.0 network. This is useful when a client needs to reach devices located in the OpenVPN server’s LAN. </td>
    </tr>
    <tr>
      <td>Allow duplicate certificates</td>
      <td>yes {{!}} no; Default: '''no'''</td>
      <td>If checked, the server allows clients to connect with identical certificates</td>
    </tr>
    <tr>
    <td>Certificate authority</td>
        <td>.ca file; Default: " "</td>
        <td>Certificate authority is an entity that issues digital certificates. A digital certificate certifies the ownership of a public key by the named subject of the certificate </td>
    </tr>
    <tr>
    <td>Server certificate</td>
        <td>.crt file; Default: " "</td>
        <td>Server certificate is a type of digital certificate that is used to identify the OpenVPN server</td>
    </tr>
    <tr>
    <td>Server key</td>
        <td>.key file; Default: " "</td>
        <td>Authenticates clients to the server </td>
    </tr>
    <tr>
    <td>Diffie Hellman parameters</td>
        <td>.pem file; Default: " "</td>
        <td>DH parameters define how OpenSSL performs the Diffie-Hellman (DH) key-exchange. </td>
    </tr>
</table>
 
'''*''' You can find detailed instructions on how to generate your own TLS certificates '''[[How to generate TLS certificates (Windows)?|here]]'''.
 
===TLS Clients===
----
TLS Clients is a way to more specifically differentiate clients by their '''Common Name (CN)''' found in the client certificate file. It can be used to assign specific VPN addresses to specific clients and bind them to their LAN addresses so that other device‘s in the client‘s LAN can be reached from the server or other clients.
 
The TLS Clients section can be found in the OpenVPN Server configuration window, provided that the OpenVPN server uses TLS or TLS/Password authentication methods. To create a new TLS client, type in the new client‘s name in the text field found bellow the TLS Clients tab and press the '''Add''' button.
 
[[Image:Services vpn openvpn tlsclients.PNG]]
 
<table class="nd-mantable">
    <tr>
        <th>field name</th>
      <th>value</th>
      <th>description</th>
    </tr>
    <tr>
      <td>VPN instance name</td>
      <td>string; Default: " "</td>
      <td>With what VPN instance should the TLS Client be associated with</td>
    </tr>
    <tr>
      <td>Endpoint name</td>
      <td>string; Default: " "</td>
      <td>Your endpoint name</td>
    </tr>
    <tr>
    <td>Common name (CN)</td>
        <td>string; Default: " "</td>
        <td>Client’s Common Name (CN) found in the client’s certificate file</td>
    </tr>
    <tr>
    <td>Virtual local endpoint</td>
        <td>ip; Default: " "</td>
        <td>Client’s virtual local address in the virtual network</td>
    </tr>
    <tr>
      <td>Virtual remote endpoint</td>
      <td>ip; Default: " "</td>
      <td>Client’s virtual remote address in the virtual network</td>
    </tr>
    <tr>
    <td>Private network</td>
        <td>ip; Default: " "</td>
        <td>Client’s private network (LAN) IP address</td>
    </tr>
    <tr>
    <td>Private netmask</td>
        <td>ip; Default: " "</td>
        <td>Client’s private network (LAN) IP netmask</td>
    </tr>
</table>
 
==IPsec==
 
The IPsec protocol client enables the router to establish a secure connection to an IPsec peer via the Internet. IPsec is supported in two modes - transport and tunnel. Transport mode creates a secure point to point channel between two hosts. Tunnel mode can be used to build a secure connection between two remote LANs serving as a VPN solution.
 
IPsec system maintains two databases: Security Policy Database (SPD) which defines whether to apply IPsec to a packet or not and specify which/how IPsec-SA is applied and Security Association Database (SAD), which contains a Key of each IPsec-SA.
 
The establishment of the Security Association (IPsec-SA) between two peers is needed for IPsec communication. It can be done by using manual or automated configuration.
 
'''NOTE''': the router starts establishing a tunnel when data is sent from the router to a remote site over the tunnel. The Keep Alive feature is used for automatic tunnel establishment.
----
For a more in-depth configuration example, visit the '''[[IPsec configuration examples]]''' page.
----
To create a new IPsec instance, go to the IPsec tab, type in a name for your new instance in the text field below the IPsec tab and press the '''Add''' button next to it.
 
'''NOTE''': You can create a maximum of 5 IPsec instances.
 
 
[[File:Services vpn ipsec v 2.png]]
 
<table class="nd-mantable">
    <tr>
        <th>field name</th>
      <th>value</th>
      <th>description</th>
    </tr>
    <tr>
    <td>Enable</td>
        <td>yes {{!}} no; Default: '''no'''</td>
        <td>Toggles the IPsec instance ON or OFF</td>
    </tr>
    <tr>
    <td>IKE version</td>
        <td>IKEv1 {{!}} IKEv2; Default: '''IKEv1'''</td>
        <td>Method of key exchange</td>
    </tr>
    <tr>
      <td>Mode</td>
      <td>Main {{!}} Aggressive; Default: '''Main'''</td>
      <td>ISAKMP phase 1 exchange mode</td>
    </tr>
    <tr>
      <td>Type</td>
      <td>Tunnel {{!}} Transport; Default: '''Tunnel'''</td>
      <td>Type of connection. <br> '''Tunnel''': protects the internal routing information by encrypting the IP header of the original packet. The original packet is encapsulated by a another set of IP headers. NAT traversal is supported with the tunnel mode. <br> '''Transport''': encrypts only the payload and Encapsulating Security Payload (ESP) trailer; so the IP header of the original packet is not encrypted. Transport mode is usually used when another tunneling protocol (such as [[RUT900 VPN#GRE_Tunnel|GRE]], [[RUT900 VPN#L2TP|L2TP]] (click '''[[L2TP over IPsec|here]]''' for a configuration example on '''L2TP over IPsec''')) is used to first encapsulate the IP data packet, then IPsec is used to protect the GRE/L2TP tunnel packets. NAT traversal is not supported with the transport mode.</td>
    </tr>
    <tr>
    <td>My identifier type</td>
        <td>Address {{!}} FQDN {{!}} User FQDN; Default: '''FQDN'''</td>
        <td>Type of connection</td>
    </tr>
    <tr>
    <td>My identifier</td>
        <td>string; Default: " "</td>
        <td>In case RUT has a Private IP, its identifier should be its own LAN network address. In this way, the Road Warrior approach is possible</td>
    </tr>
    <tr>
      <td>Local IP address/Subnet mask</td>
      <td>ip/netmask {{!}} Default: " "</td>
      <td>Local network secure group IP address and mask used to determine at what subnet an IP address can be accessed. Netmask range [0 - 32]. If left empty IP address will be selected automatically</td>
    </tr>
    <tr>
      <td>Left firewall</td>
      <td>yes {{!}} no; Default: '''yes'''</td>
      <td>Excludes IPsec tunnel from firewall rules</td>
    </tr>
    <tr>
    <td>Force encapsulation</td>
        <td>yes {{!}} no; Default: '''no'''</td>
        <td>Forces UDP encapsulation for ESP packets even if no NAT situation is detected</td>
    </tr>
    <tr>
    <td>Dead Peer Detection</td>
        <td>yes {{!}} no; Default: '''no'''</td>
        <td>The values 'clear', 'hold' and 'restart' all activate DPD</td>
    </tr>
    <tr>
      <td>Pre-shared key</td>
      <td>string; Default: " "</td>
      <td>A shared password used for authentication between the peers</td>
    </tr>
    <tr>
      <td>Remote VPN endpoint</td>
      <td>host {{!}} ip; Default: " "</td>
      <td>IP address or hostname of the remote IPsec instance</td>
    </tr>
    <tr>
    <td>Remote IP address/subnet mask</td>
        <td>ip/integer [0..32]; Default: " "</td>
        <td>Remote network secure group IP address and mask used to determine to what subnet an IP address belongs to. Should differ from device’s LAN IP</td>
    </tr>
    <tr>
    <td>Right firewall</td>
        <td>yes {{!}} no; Default: '''yes'''</td>
        <td>Excludes remote side IPsec tunnel from firewall rules</td>
    </tr>
    <tr>
      <td>Enable keep alive</td>
      <td>yes {{!}} no; Default: '''no'''</td>
      <td>Toggles the tunnel's keep alive function ON or OFF. When enabled, the instance sends ICMP packets to the specified host at the specified frequency. If no response is received, the instance attempts to restart the connection</td>
    </tr>
    <tr>
      <td>Host</td>
      <td>host {{!}} ip; Default: " "</td>
      <td>Hostname or IP address to which ICMP packets will be sent to. Best to use a hostname/IP address belonging to the opposite instance's LAN</td>
    </tr>
    <tr>
    <td>Ping period (sec)</td>
        <td>integer [0..9999999]; Default: " "</td>
        <td>The period (in seconds) at which ICMP packets will be sent to the specified keep alive host</td>
    </tr>
    <tr>
    <td>Allow WebUI access</td>
        <td>yes {{!}} no; Default: '''no'''</td>
        <td>Allows WebUI access for hosts from the opposite instance</td>
    </tr>
</table>
 
===Phase 1/Phase 2===
----
'''Phase''' 1 and '''Phase 2''' must be configured in accordance with the IPSec server configuration, thus algorithms, authentication and lifetimes of each phase must be identical.
 
 
[[Image:Services vpn ipsec phase.PNG]]
 
<table class="nd-mantable">
    <tr>
        <th>field name</th>
      <th>value</th>
      <th>description</th>
    </tr>
    <tr>
      <td>Encryption algorithm</td>
      <td>DES {{!}} 3DES {{!}} AES 128 {{!}} AES 192 {{!}} AES256; Default: '''3DES'''</td>
      <td>The encryption algorithm must match with another incoming connection</td>
    </tr>
    <tr>
      <td>Authentication</td>
      <td>MD5 {{!}} SHA1 {{!}} SHA256 {{!}} SHA384 {{!}} SHA512; Default: '''SHA1'''</td>
      <td>The authentication algorithm must match with another incoming connection</td>
    </tr>
    <tr>
    <td>Has algorithm</td>
        <td>MD5 {{!}} SHA1 {{!}} SHA256 {{!}} SHA384 {{!}} SHA512; Default: '''SHA1'''</td>
        <td>The hash algorithm must match with another incoming connection</td>
    </tr>
    <tr>
    <td>DH group</td>
        <td>MODP768 {{!}} MODP1024 {{!}} MODP1536 {{!}} MODP2048 {{!}} MODP3072 {{!}} MODP4096; Default: '''MODP1536'''</td>
        <td>The DH (Diffie-Helman) group must match with another incoming connection</td>
    </tr>
    <tr>
    <td>PFS group</td>
        <td>MODP768 {{!}} MODP1024 {{!}} MODP1536 {{!}} MODP2048 {{!}} MODP3072 {{!}} MODP4096 {{!}} No PFS; Default: '''MODP1536'''</td>
        <td>The PFS (Perfect Forward Secrecy) group must match with another incoming connection</td>
    </tr>
    <tr>
    <td>Lifetime</td>
        <td>time; Default: '''8 hours'''</td>
        <td>Duration for the phase</td>
    </tr>
</table>
 
==GRE Tunnel==
 
'''GRE''' (Generic Routing Encapsulation RFC2784) is a solution for tunneling RFC1812 private address-space traffic over an intermediate TCP/IP network such as the Internet. GRE tunneling does not use encryption it simply encapsulates data and sends it over the wide area network (WAN).
 
 
[[Image:Services vpn gre tunnel scheme.PNG]]
 
In the example network diagram two distant networks LAN1 and LAN2 are connected. To create A GRE tunnel the user must know the following parameters:
 
* Source and destination IP addresses
* Tunnel’s local IP address
* Distant network’s IP address and Subnet mask
 
To create a new GRE instance, go to the GRE Tunnel tab, type in a name for your new instance in the text field below the GRE Tunnel tab and press the '''Add New''' button next to it.
The newly created instance will be disabled and unconfigured. To configure it press the '''Edit''' button located next to it. This action will redirect you to the instance’s GRE Tunnel Configuration window.
 
 
[[Image:Services vpn gre tunnel configuration.PNG]]
 
<table class="nd-mantable">
    <tr>
        <th>field name</th>
      <th>value</th>
      <th>description</th>
    </tr>
    <tr>
      <td>Enabled</td>
      <td>yes {{!}} no; Default: '''no'''</td>
      <td>Toggles GRE Tunnel ON or OFF</td>
    </tr>
    <tr>
      <td>Remote endpoint IP address</td>
      <td>ip; Default: " "</td>
      <td>WAN IP address or hostname of the remote GRE Tunnel instance</td>
    </tr>
    <tr>
    <td>Remote network</td>
        <td>integer [0..32]; Default: " "</td>
        <td>LAN IP address of the remote device</td>
    </tr>
    <tr>
    <td>Remote network netmask</td>
        <td>integer [0..32]; Default: " "</td>
        <td>LAN netmask of the remote device</td>
    </tr>
    <tr>
      <td>Local tunnel IP</td>
      <td>ip; Default: " "</td>
      <td>Local virtual IP address. Can’t be in the same subnet as LAN network</td>
    </tr>
    <tr>
      <td>MTU</td>
      <td>integer [0..255]; Default: '''255'''</td>
      <td>Toggles the Path Maximum Transmission Unit Discovery (PMTUD) status on this tunnel ON or OFF</td>
    </tr>
    <tr>
    <td>TTL</td>
        <td>integer [0..255]; Default: '''255'''</td>
        <td>Fixed time-to-live (TTL) value on tunneled packets. The 0 is a special value meaning that packets inherit the TTL value</td>
    </tr>
    <tr>
    <td>PMTUD</td>
        <td>yes {{!}} no; Default: '''no'''</td>
        <td>Toggles the Path Maximum Transmission Unit Discovery (PMTUD) status on this tunnel ON or OFF</td>
    </tr>
    <tr>
      <td>Redirect LAN to GRE</td>
      <td>yes {{!}} no; Default: '''no'''</td>
      <td>Redirects LAN traffic to the GRE interface</td>
    </tr>
    <tr>
      <td>Enable Keep alive</td>
      <td>yes {{!}} no; Default: '''no'''</td>
      <td>Gives the ability for one side to originate and receive keep alive packets to and from a remote router</td>
    </tr>
    <tr>
    <td>Keep Alive host</td>
        <td>host {{!}} ip; Default: " "</td>
        <td>Keep Alive IP address to send pings to. Preferably this should be an IP address which belongs to the LAN network on the remote device</td>
    </tr>
    <tr>
    <td>Keep alive interval</td>
        <td>integer [0..255]; Default: " "</td>
        <td>Frequency at which ICMP packets are sent by the Keep Alive function (in seconds)</td>
    </tr>
</table>
 
To find a more in-depth GRE Tunnel configuration example, visit '''[[GRE Tunnel configuration examples|this page]]
 
==PPTP==
 
'''Point-to-Point Tunneling Protocol (PPTP)''' is a protocol (set of communication rules) that allows corporations to extend their own corporate network through private "tunnels" over the public Internet. Effectively, a corporation uses a wide-area network as a single large local area network. A company no longer needs to lease its own lines for wide-area communication but can securely use the public networks.
 
For a more in-depth configuration example, visit the '''[[PPTP configuration examples]]''' page.
 
===PPTP Client===
----
To create a new PPTP instance, go to the PPTP tab, select the Role (server or client) of your instance, type in a name in the '''New configuration name''' field and press the '''Add''' button next to it. The newly created instance will be disabled and unconfigured. To configure it click the '''Edit''' button located next to it. This action will redirect you to the instance’s PPTP Configuration window.
 
 
[[Image:Services vpn pptp client.PNG]]
 
<table class="nd-mantable">
    <tr>
        <th>field name</th>
      <th>value</th>
      <th>description</th>
    </tr>
    <tr>
      <td>Enable</td>
      <td>yes {{!}} no; Default: '''no'''</td>
      <td>Toggles PPTP Client ON or OFF</td>
    </tr>
    <tr>
      <td>Use as default gateway</td>
      <td>yes {{!}} no; Default: '''no'''</td>
      <td>Use this PPTP instance as default gateway</td>
    </tr>
    <tr>
    <td>Client to client</td>
        <td>yes {{!}} no; Default: '''no'''</td>
        <td>Toggles client to client on the PPTP tunnel ON or OFF</td>
    </tr>
    <tr>
    <td>Server</td>
        <td>host {{!}} ip; Default: " "</td>
        <td>PPTP server's IP address or hostname</td>
    </tr>
    <tr>
    <td>Username</td>
        <td>string; Default: " "</td>
        <td>User name for authorization with the server</td>
    </tr>
    <tr>
    <td>Password</td>
        <td>string; Default: " "</td>
        <td>Password used for authorization with the server</td>
    </tr>
</table>
 
===PPTP Server===
----
[[Image:Services vpn pptp server.PNG]]
 
<table class="nd-mantable">
    <tr>
        <th>field name</th>
      <th>value</th>
      <th>description</th>
    </tr>
    <tr>
      <td>Enable</td>
      <td>yes {{!}} no; Default: '''no'''</td>
      <td>Toggles PPTP Server ON or OFF</td>
    </tr>
    <tr>
      <td>Local IP</td>
      <td>ip; Default: '''192.168.0.1'''</td>
      <td>Virtual IP Address of this PPTP server</td>
    </tr>
    <tr>
    <td>Remote IP range begin</td>
        <td>ip; Default: '''192.168.0.20'''</td>
        <td>Client IP address leases beginning</td>
    </tr>
    <tr>
    <td>Remote IP range end</td>
        <td>ip; Default: '''192.168.0.30'''</td>
        <td>Client IP address leases end</td>
    </tr>
    <tr>
      <td>User name</td>
      <td>string; Default: '''youruser'''</td>
      <td>Client's user name used for authentication with this server</td>
    </tr>
    <tr>
    <td>Password</td>
        <td>string; Default: '''yourpass'''</td>
        <td>Client's password used for authentication with this server</td>
    </tr>
    <tr>
    <td>PPTP Client's IP</td>
        <td>ip; Default: " "</td>
        <td>Client’s IP address. Leave empty to assign a random IP from the IP range specified above</td>
    </tr>
</table>
 
==L2TP==
 
In computer networking, '''Layer 2 Tunneling Protocol (L2TP)''' is a tunneling protocol used to support virtual private networks (VPNs). It is more secure than PPTP but, because it encapsulates the transferred date twice, but it is slower and uses more CPU power.
 
For a more in-depth configuration example, visit the '''[[L2TP configuration examples]]''' page.
 
===L2TP Client===
----
To create a new L2TP instance, go to the L2TP tab, select the Role (server or client) of your instance, type in a name in the '''New configuration name''' field and press the '''Add''' button next to it. The newly created instance will be disabled and unconfigured. To configure it press the '''Edit''' button located next to it. This action will redirect you to the instance’s L2TP Configuration window.
 
 
[[Image:Services vpn l2tp client configuration.PNG]]
 
<table class="nd-mantable">
    <tr>
        <th>field name</th>
      <th>value</th>
      <th>description</th>
    </tr>
    <tr>
      <td>Enable</td>
      <td>yes {{!}} no; Default: '''no'''</td>
      <td>Toggles L2TP Client ON or OFF</td>
    </tr>
    <tr>
      <td>Server</td>
      <td>host {{!}} ip; Default: " "</td>
      <td>L2TP server's remote IP address or hostname</td>
    </tr>
    <tr>
    <td>Username</td>
        <td>string; Default: " "</td>
        <td>User name used to authenticate you to the L2TP server</td>
    </tr>
    <tr>
    <td>Password</td>
        <td>string; Default: " "</td>
        <td>Password used to authenticate you to the server</td>
    </tr>
</table>
 
===L2TP Server===
----
[[Image:Services vpn l2tp server.PNG]]
 
<table class="nd-mantable">
    <tr>
        <th>field name</th>
      <th>value</th>
      <th>description</th>
    </tr>
    <tr>
      <td>Enable</td>
      <td>yes {{!}} no; Default: '''no'''</td>
      <td>Toggles L2TP Server ON or OFF</td>
    </tr>
    <tr>
      <td>Local IP</td>
      <td>ip; Default: '''192.168.0.1'''</td>
      <td>Virtual IP Address of this L2TP server</td>
    </tr>
    <tr>
    <td>Remote IP range begin</td>
        <td>ip; Default: '''192.168.0.20'''</td>
        <td>Client IP address leases beginning</td>
    </tr>
    <tr>
    <td>Remote IP range end</td>
        <td>ip; Default: '''192.168.0.30'''</td>
        <td>Client IP address leases end</td>
    </tr>
    <tr>
    <td>User name</td>
        <td>string; Default: '''user'''</td>
        <td>Client's user name used for authentication with this server</td>
    </tr>
    <tr>
    <td>Password</td>
        <td>string; Default: '''pass'''</td>
        <td>Client's password used for authentication with this server</td>
    </tr>
</table>
==Stunnel==
 
'''Stunnel''' is an open-source multi-platform software application used to provide a TLS/SSL tunneling service for already existing clients and servers. Below is an overview of the Stunnel application and its WebUI configuration section implemented on RUTxxx routers. For in-depth examples please visit '''[[Stunnel configuration examples|Stunnel page]]'''.
 
Here is an approximate visual representation of Stunnel connection:
 
[[Image:draw_io_simple_stunnel.png]]
 
 
Upon creation, Stunnel configuration will be empty. User is expected to define their own configuration using the created configuration template. Stunnel provided encryption and connection will only work with properly configured Stunnel server(s) and client(s).
 
Duplicate configuration names are not allowed.
 
Stunnel configuration list window is located at '''Services → VPN → Stunnel''':
 
Services menu, VPN section:
 
[[Image:stunnel_config_menu.png]]
 
Stunnel tab:
 
[[Image:stunnel_config_tab.png]]
 
 
To create a new configuration, enter the desired name in field below all configuration list entries and click button '''Add''':
 
[[Image:stunnel_config_creation.png]]
 
Once you’ve added a new Stunnel configuration, it is automatically saved - no need to press the '''Save''' button.
 
By default the configuration will be disabled and unconfigured. You can change the configuration by clicking the '''Edit''' button and delete the configuration by clicking the '''Delete''' button.
 
[[Image:stunnel_edit_button.png]]
 
To establish an Stunnel connection you must have configured and enabled Stunnel client and server instances on either same or different routers.
 
===Stunnel Configuration===
 
Default Stunnel configuration:
 
[[Image:stunnel_default_config.png]]
 
 
Stunnel configuration field explanation table:
 
<table class="nd-mantable">
    <tr>
        <th>Field Name</th>
        <th>Value</th>
        <th>Description</th>
    </tr>
    <tr>
        <td>Enabled</td>
        <td>yes {{!}} no; Default: '''no'''</td>
        <td>Enables the Stunnel configuration.</td>
    </tr>
    <tr>
        <td>Operating Mode</td>
        <td>Client {{!}} Server; Default: ""</td>
        <td>Specifies whether this configuration will be used for Stunnel client or server.</td>
    </tr>
    <tr>
        <td>Listen IP</td>
        <td>ip {{!}} host; Default: ""</td>
        <td>'''OPTIONAL'''
 
Specifies which IP address or host should Stunnel listen to. If left empty, defaults to '''localhost'''.</td>
    </tr>
    <tr>
        <td>Listen Port</td>
        <td>port (integer [0..65535]); Default: ""</td>
        <td>Specifies TCP port which Stunnel should listen to. '''Port cannot be taken by another service!'''</td>
    </tr>
    <tr>
        <td>Connect IP's</td>
        <td>[host:]port; Default: ""</td>
        <td>Uses the standard host:port convetion (e.g. 127.0.0.1:6001; localhost:6001). Host part can be emmited - empty host part defaults to '''localhost'''.
 
Must contain at least one item. If multiple options are specified, remote address is chosen using a round-robin algorithm.</td>
    </tr>
    <tr>
        <td>TLS Cipher</td>
        <td>None {{!}} Secure {{!}} Custom</td>
        <td>Select permitted TLS ciphers (TLSv1.2 and below). If custom is selected, a new field appears to enter custom ciphers.</td>
    </tr>
    <tr>
        <td>Allowed TLS Ciphers</td>
        <td>Cipher[:Cipher]..; Default: ""</td>
        <td>''Only appears if a Custom TLS Cipher is selected''<br>
 
A colon-delimited TLS cipher list (e.g. DES-CBC3-SHA:IDEA-CBC-MD5)</td>
    </tr>
    <tr>
        <td>Application Protocol</td>
        <td>Not specified {{!}} Connect {{!}} SMTP; Default: '''Not specified'''</td>
        <td>'''CLIENT SIDE ONLY'''
 
This option enables initial, protocol-specific negotiation of the TLS encryption. The protocol option should not be used with TLS encryption on a separate port.
 
If ''Connect'' or ''SMTP'' is selected, more customization fields appear.</td>
    </tr>
    <tr>
        <td>Protocol Authentication</td>
        <td>'''Connect:''' Basic {{!}} NTLM; Default: '''Basic'''
 
            '''SMTP:''' Plain {{!}} Login; Default: '''Plain'''</td>
        <td>'''CLIENT SIDE ONLY'''
 
''Options depend on the selected protocol''
 
Authentication type for the protocol negotiations.</td>
    </tr>
    <tr>
        <td>Protocol Domain</td>
        <td>domain (text); Default: ""</td>
        <td>'''CLIENT SIDE ONLY'''
       
''Only appears if a Connect protocol is selected''
           
Domain for the protocol negotiations.</td>
    </tr>
    <tr>
        <td>Protocol Host</td>
        <td>host:port; Default: ""</td>
        <td>'''CLIENT SIDE ONLY'''
       
''Only appears if a Connect protocol is selected''
           
Destination address for the protocol negotiations.
           
Specifies the final TLS server to be connected to by the proxy, and not the proxy server directly connected by '''Stunnel'''. The proxy server should be specified with the '''connect''' option.</td>
    </tr>
    <tr>
        <td>Protocol Username</td>
        <td>username (text); Default: ""</td>
        <td>'''CLIENT SIDE ONLY'''
       
''Only appears if a protocol is selected''
           
Username for the protocol negotiations.</td>
    </tr>
    <tr>
        <td>Protocol Password</td>
        <td>password (text); Default: ""</td>
        <td>'''CLIENT SIDE ONLY'''
       
''Only appears if a protocol is selected''
           
Password for the protocol negotiations.</td>
    </tr>
    <tr>
        <td>Verification</td>
        <td>None {{!}} Verify Chain {{!}} Verify Peer; Default: '''None'''</td>
        <td>Verification type. '''Verify Chain''' verifies connections against a Certificate Authority (CA) file, while '''Verify Peer''' verifies connections against a list of approved certificates.</td>
    </tr>
    <tr>
        <td>Verification file</td>
        <td>file; Default: ""</td>
        <td>''Only appears if a verification type is selected''
       
File which is used to verify peer(s) or a peer chain. A different type of file is expected depending on the verification type selected:
           
'''Verify Chain:''' Expects a CA (Certificate Authority) file.
 
'''Verify Peer:''' Expects a file with one (or more, concatenated) peer certificate(s).</td>
    </tr>
    <tr>
        <td>Certificate File</td>
        <td>file; Default: ""</td>
        <td>'''Mandatory for a server configuration. Optional for a client configuration'''
       
The parameter specifies the file containing certificates used by stunnel to authenticate itself against the remote client or server.
       
The file should contain the whole certificate chain starting from the actual server/client certificate, and ending with the self-signed root CA certificate.
           
Can be a certificate only, or both certificate and private key concatenated into a single file.</td>
    </tr>
    <tr>
        <td>Private Key</td>
        <td>file; Default: '''Certificate File'''</td>
        <td>''Can be skipped if the Certificate File is appended with the private key''
       
''Must be uploaded if the Certificate File does not contain the private key''
           
A private key, required to authenticate the certificate owner.</td>
    </tr>
</table>
 
After setting the parameters, click the '''Save''' button; otherwise, changes will not be saved. Some parameters will be shown in the configuration list table.
 
 
===Stunnel Global Configuration===
 
Default Stunnel global configuration:
 
[[Image:stunnel_default_global_config.png]]
 
 
Stunnel global configuration field explanation table:
 
<table class="nd-mantable">
    <tr>
        <th>Field Name</th>
        <th>Value</th>
        <th>Description</th>
    </tr>
    <tr>
        <td>Enabled</td>
        <td>yes {{!}} no; Default: '''no'''</td>
        <td>Enables/activates all the enabled Stunnel configurations.</td>
    </tr>
    <tr>
        <td>Debug Level</td>
        <td>integer [0..7]; Default: '''5'''</td>
        <td>Debugging level.
       
Level is one of the syslog level names or numbers emerg (0), alert (1), crit (2), err (3), warning (4), notice (5), info (6), or debug (7). All logs for the specified level and all levels numerically less than it will be shown. Use '''7''' for greatest debugging output.</td>
    </tr>
    <tr>
        <td>Use alternative config</td>
        <td>yes {{!}} no; Default: '''no'''</td>
        <td>Enable alternative configuration option (Config upload).
       
Be aware that when using alternative configuration, all configurations in '''Stunnel Configuration''' section will be skipped.</td>
    </tr>
    <tr>
        <td>Upload alternative config</td>
        <td>file; Default: ""</td>
        <td>''Only appears if the "Use alternative config" is enabled''<br>
       
Upload the alternative Stunnel configuration file.</td>
    </tr>
</table>
 
 
'''''IMPORTANT:'''''
 
The router can have multiple configurations set up and enabled at the same time. Note that if at least one configuration is not set correctly, '''none of them will be enabled''', despite the "Enabled" flag being marked.
 
Also, you must mark the global "Enabled" flag to actually enable all the individually marked configurations.
 
==See also==
 
* Configuration examples for RUTxxx VPN services:
** [[OpenVPN configuration examples]]
** [[IPsec configuration examples]]
** [[GRE Tunnel configuration examples]]
** [[PPTP configuration examples]]
** [[L2TP configuration examples]]
** [[Stunnel configuration examples]]
* Configuration examples for third party VPN services
** [[expressvpn.com VPN configuration|expressvpn.com]]
** [[vpngate.net VPN configuration|vpngate.net]]
** [[Vpnbook.com VPN configuration|vpnbook.com]]
** [[hide.me VPN configuration|hide.me]]
* Other related examples:
** [[How to generate TLS certificates (Windows)?]]
** [[How to generate TLS certificates (Linux)?]]
** [[L2TP over IPsec]]
** [[OpenVPN traffic split]]
** [[OpenVPN client on Windows]]

Latest revision as of 10:12, 9 April 2024

Main Page > EOL Products > RUT900 > RUT900 Manual > RUT900 WebUI > RUT900 Services section > RUT900 VPN

The information in this page is updated in accordance with firmware version .
Note: click here for the old style WebUI (FW version RUT9XX_R_00.06.09.5 and earlier) user manual page.

Summary

Virtual Private Network (VPN) is a method of connecting multiple private networks across the Internet. VPNs can serve to achieve many different goals, but some of its main purposes are:

  • access between remote private networks;
  • data encryption;
  • anonymity when browsing the Internet.

This page is an overview of the different types of VPNs supported by RUT900 devices.

OpenVPN

OpenVPN is an open-source software application that implements virtual private network (VPN) techniques for creating secure point-to-point or site-to-site connections in routed or bridged configurations and remote access facilities. It is often regarded as being the most universal VPN protocol because of its flexibility, support of SSL/TLS security, multiple encryption methods, many networking features and compatibility with most OS platforms.

RUT900 devices run OpenVPN version 2.5.3.

OpenVPN Client


An OpenVPN client is an entity that initiates a connection to an OpenVPN server. To create a new client instance, go to the Services → VPN → OpenVPN section, select Role: Client, enter a custom name and click the 'Add' button. An OpenVPN client instance with the given name will appear in the "OpenVPN Configuration" list.

To begin configuration, click the button that looks like a pencil next to the client instance. Refer to the figure and table below for information on the OpenVPN client's configuration fields:

Field Value Description
Enable off | on; default: off Turns the OpenVPN instance on or off.
Enable external Services off |on; default: off Turns the OpenVPN external Services on or off.
VPN providers Express VPN | Nord VPN; default: Nord VPN Represents a list of available VPN providers.
VPN servers United Kingdom | USA | Australia | South Africa | Custom; default: United Kingdom Represents a list of available VPN servers.
Username string; default: none Username used for authentication to the VPN server.
Password string; default: none Password used for authentication to the VPN server.
Enable OpenVPN config from file off | on; default: off Enables or disables custom OpenVPN config from file.
OpenVPN configuration file -(interactive button) Upload OpenVPN configuration. Warning! This will overwrite your current configuration.
Upload OpenVPN authentications files off | on; default: off Upload OpenVPN authentication files, which will be automatically included in configuration.
TUN/TAP TUN (tunnel) | TAP (bridged); default: TUN (tunnel) Virtual network device type.
  • TUN - a virtual point-to-point IP link which operates at the network layer (OSI layer 3), used when routing is required.
  • TAP - a virtual Ethernet adapter (switch), operates at the data link layer (OSI layer 2), used when bridging is required.
Protocol UDP | TCP | UDP6 | TCP6; default: UDP Transfer protocol used by the OpenVPN connection.
  • Transmission Control Protocol (TCP) - most commonly used protocol in the Internet Protocol (IP) suite. It ensures the recipient will receive packets in the order they were sent by numbering, analysing response messages, checking for errors and resending them if an issue occurs. It should be used when reliability is crucial (for example, in file transfer).
  • User Datagram Protocol (UDP) - packets are sent to the recipient without error-checking or back-and-forth quality control, meaning that when packets are lost, they are gone forever. This makes it less reliable but faster than TCP; therefore, it should be used when transfer speed is crucial (for example, in video streaming, live calls).
Port integer [0..65535]; default: 1194 TCP/UDP port number used for the connection. Make sure it matches the port number specified on the server side.
NOTE: traffic on the selected port will be automatically allowed in the device firewall rules.
LZO Yes | No | None; default: None Turns LZO data compression on or off.
Authentication TLS | Static Key | Password | TLS/Password; default: TLS Authentication mode, used to secure data sessions.
  • Static key is a secret key used for server–client authentication.
  • TLS authentication mode uses X.509 type certificates:
    • Certificate Authority (CA)
    • Client certificate
    • Client key
    All mentioned certificates can be generated using OpenVPN or Open SSL utilities on any type of host machine. One of the most popular utilities used for this purpose is called Easy-RSA.
  • Password is a simple username/password based authentication where the owner of the OpenVPN server provides the login data.
  • TLS/Password uses both TLS and username/password authentication.
Encryption DES-CBC 64 | RC2-CBC 128 | DES-EDE-CBC 128 | DES-EDE3-CBC 192 | DESX-CBC 192 | BF-CBC 128 | RC2-40-CBC 40 | CAST5-CBC 128 | RC2-64CBC 64 | AES-128-CBC 128 | AES-128-CFB 128 | AES-128-CFB1 128 | AES-128-CFB8 128 | AES-128-OFB 128 | AES-128-GCM 128 | AES-192-CBC 192 | AES-192-CFB 192 | AES-192-CFB1 192 | AES-192-CFB8 192 | AES-192-OFB 192 | AES-192-GCM 192 | AES-256-CBC 256 | AES-256-CFB 256 | AES-256-CFB1 256 | AES-256-CFB8 256 | AES-256-OFB 256 | AES-256-GCM 256 | none; default: AES-256-CBC 256 Algorithm used for packet encryption.
TLS: TLS cipher All | DHE+RSA | Custom; default: All Packet encryption algorithm cipher.
TLS: Allowed TLS ciphers All | DHE+RSA | Custom; default: All A list of TLS ciphers accepted by this connection.
Remote host/IP address ip; default: none IP address or hostname of an OpenVPN server.
Resolve retry integer | infinite; default: infinite In case server hostname resolve fails, this field indicates the amount of time (in seconds) to retry the resolve. Specify infinite to retry indefinitely.
Keep alive two integers separated by a space; default: 10 120 Defines two time intervals: the first is used to periodically send ICMP requests to the OpenVPN server, the second one defines a time window, which is used to restart the OpenVPN service if no ICMP response is received during the specified time slice. When this value is specfiied on the OpenVPN server, it overrides the 'keep alive' values set on client instances.
Example: 10 120
Static key: Local tunnel endpoint IP ip; default: none IP address of the local OpenVPN network interface.
Static key: Remote tunnel endpoint IP ip; default: none IP address of the remote OpenVPN network (server) interface.
Remote network IP address ip4; default: none LAN IP address of the remote network (server).
Remote network netmask netmask; default: none LAN IP subnet mask of the remote network (server).
Remote network IPv6 address ip6; default: none IPv6 address of the remote network (server). This field is becomes visible when protocol is set to UDP6 or TCP6
Password: User name string; default: none Username used for authentication to the OpenVPN server.
Password: Password string; default: none Password used for authentication to the OpenVPN server.
TLS/Password:Use PKCS #12 format off | on; default: off Turn PKCS #12 format on or off.
Extra options string; default: none Extra OpenVPN options to be used by the OpenVPN instance.
Certificate files from device off | on; default: off Turn on this option if you want to select generated certificate files from device.
TLS/Password: HMAC authentication algorithm none | SHA1 | SHA256 | SHA384 | SHA512; default: SHA1 HMAC authentication algorithm type.
TLS/Password:Additional HMAC authentication off | on; default: off An additional layer of HMAC authentication on top of the TLS control channel to protect against DoS attacks.
TLS/Password: HMAC authentication key .key file; default: none Uploads an HMAC authentication key file.
TLS/Password: HMAC key direction 0 | 1 | none; default: 1 The value of the key direction parameter should be complementary on either side (client and server) of the connection. If one side uses 0, the other side should use 1, or both sides should omit the parameter altogether.
TLS/Password: Certificate authority .ca file; default: none Certificate authority is an entity that issues digital certificates. A digital certificate certifies the ownership of a public key by the named subject of the certificate.
TLS: Client certificate .crt file; default: none Client certificate is a type of digital certificate that is used by client systems to make authenticated requests to a remote server. Client certificates play a key role in many mutual authentication designs, providing strong assurances of a requester's identity.
TLS: Client key .key file; default: none Authenticates the client to the server and establishes precisely who they are.
TLS: Private key decryption password (optional) string; default: none A password used to decrypt the server's private key. Use only if server's .key file is encrypted with a password.
Static key: Static pre-shared key .key file; default: none Uploads a secret key file used for server–client authentication.

Additional notes:

  • Some configuration fields become available only when certain other parameters are selected. The names of the parameters are followed by a prefix that specifies the authentication type under which they become visible. Different color codes are used for different prefixes:
    • Red for Authentication: TLS
    • Purple for Authentication: Static key
    • Blue for Authentication: Password
  • After changing any of the parameters, don't forget to click the Save & Apply button located at the bottom-right side of the page.

OpenVPN Server


An OpenVPN server is an entity that waits for incoming connections from OpenVPN clients. To create a new server instance, go to the Services → VPN → OpenVPN section, select Role: Server, enter a custom name and click the 'Add' button. An OpenVPN server instance with the given name will appear in the "OpenVPN Configuration" list. Only one OpenVPN server instance is allowed to be added.

A server needs to have a public IP address in order to be available from the public network (the Internet).

To begin configuration, click the button that looks like a pencil next to the server instance. Refer to the figure and table below for information on the OpenVPN server's configuration fields:

Which SERVER LAN networks should be reachable from this client
Field Value Description
Enable off | on; default: off Turns the OpenVPN instance on or off.
Enable OpenVPN config from file off | on; default: off Enables or disables custom OpenVPN config from file.
TUN/TAP TUN (tunnel) | TAP (bridged); default: TUN (tunnel) Virtual network device type.
  • TUN - a virtual point-to-point IP link which operates at the network layer (OSI layer 3), used when routing is required.
  • TAP - a virtual Ethernet adapter (switch), operates at the data link layer (OSI layer 2), used when bridging is required.
Protocol UDP | TCP | UDP6 | TCP6; default: UDP Transfer protocol used by the OpenVPN connection.
  • Transmission Control Protocol (TCP) - most commonly used protocol in the Internet Protocol (IP) suite. It ensures the recipient will receive packets in the order they were sent by numbering, analysing response messages, checking for errors and resending them if an issue occurs. It should be used when reliability is crucial (for example, file transfer).
  • User Datagram Protocol (UDP) - packets are sent to the recipient without error-checking or back-and-forth quality control, meaning that when packets are lost, they are gone forever. This makes it less reliable but faster than TCP; therefore, it should be used when transfer speed is crucial (for example, video streaming, live calls).
Port integer [0..65535]; default: 1194 TCP/UDP port number used for the connection. Make sure it matches the port number specified on the server side.
NOTE: traffic on the selected port will be automatically allowed in device firewall rules.
LZO Yes | No | None; default: None Turns LZO data compression on or off.
Encryption DES-CBC 64 | RC2-CBC 128 | DES-EDE-CBC 128 | DES-EDE3-CBC 192 | DESX-CBC 192 | BF-CBC 128 | RC2-40-CBC 40 | CAST5-CBC 128 | RC2-64CBC 64 | AES-128-CBC 128 | AES-128-CFB 128 | AES-128-CFB1 128 | AES-128-CFB8 128 | AES-128-OFB 128 | AES-128-GCM 128 | AES-192-CBC 192 | AES-192-CFB 192 | AES-192-CFB1 192 | AES-192-CFB8 192 | AES-192-OFB 192 | AES-192-GCM 192 | AES-256-CBC 256 | AES-256-CFB 256 | AES-256-CFB1 256 | AES-256-CFB8 256 | AES-256-OFB 256 | AES-256-GCM 256 | none; default: AES-256-CBC 256 Algorithm used for packet encryption.
Authentication TLS | Static Key | TLS/Password; default: TLS Authentication mode, used to secure data sessions.
  • Static key is a secret key used for server–client authentication.
  • TLS authentication mode uses X.509 type certificates:
    • Certificate Authority (CA)
    • Client certificate
    • Client key
    All mentioned certificates can be generated using OpenVPN or Open SSL utilities on any type of host machine. One of the most popular utilities used for this purpose is called Easy-RSA.
  • TLS/Password uses both TLS and username/password authentication.
Static key: Local tunnel endpoint IP ip; default: none IP address of the local OpenVPN network interface.
Static key: Remote tunnel endpoint IP ip; default: none IP address of the remote OpenVPN network (client) interface.
Static key: Remote network IP address ip; default: none LAN IP address of the remote network (client).
Static key: Remote network IP netmask netmask; default: none LAN IP subnet mask of the remote network (client).
Static key: Authentication algorithm None | MD5 | SHA1 | SHA256 | SHA384 | SHA512; default: SHA1 Algorithm used for exchanging authentication and hash information.
TLS/TLS/Password: TLS cipher All | DHE+RSA | Custom; default: All Packet encryption algorithm cipher.
TLS/Password: Allowed TLS ciphers All | DHE+RSA | Custom; default: All A list of TLS ciphers accepted by this connection.
TLS/TLS/Password: Client to client off | on; default: off Allows OpenVPN clients to communicate with each other on the VPN network.
TLS/TLS/Password: Keep alive two integers separated by a space; default: none Defines two time intervals: the first is used to periodically send ICMP requests to the OpenVPN server, the second one defines a time window, which is used to restart the OpenVPN service if no ICMP response is received during the specified time slice. When this value is specifiied on the OpenVPN server, it overrides the 'keep alive' values set on client instances.
Example: 10 120
TLS/TLS/Password: Virtual network IP address ip4; default: none IPv4 address of the OpenVPN network.
TLS/TLS/Password: Virtual network netmask netmask; default: none Subnet mask of the OpenVPN network.
TLS/TLS/Password: Virtual network IPv6 address ip6; default: none IPv6 address of the OpenVPN network. This field becomes visible when protocol is set to UDP6 or TCP6
TLS/TLS/Password: Push option OpenVPN options; default: none Push options are a way to "push" routes and other additional OpenVPN options to connecting clients.
TLS/TLS/Password: Allow duplicate certificates off | on; default: off When enabled allows multiple clients to connect using the same certificates.
TLS/Password: User name string; default: none Username used for authentication to this OpenVPN server.
TLS/Password: Password string; default: none Password used for authentication to this OpenVPN server.
Static key: Static pre-shared key .key file; default: none Uploads a secret key file used for server–client authentication.
TLS/TLS/Password: Certificate authority .ca file; default: none Certificate authority is an entity that issues digital certificates. A digital certificate certifies the ownership of a public key by the named subject of the certificate.
TLS/TLS/Password: Server certificate .crt file; default: none A type of digital certificate that is used to identify the OpenVPN server.
TLS/TLS/Password: Server key .key file; default: none Authenticates clients to the server.
TLS/TLS/Password: Diffie Hellman parameters .pem file; default: none DH parameters define how OpenSSL performs the Diffie-Hellman (DH) key-exchange.
TLS/TLS/Password: CRL file (optional) .pem file | .crl file; Default: none A certificate revocation list (CRL) file is a list of certificates that have been revoked by the certificate authority (CA). It indicates which certificates are no longer acccepted by the CA and therefore cannot be authenticated to the server.

Additional notes:

  • Some configuration fields become available only when certain other parameters are selected. The names of the parameters are followed by a prefix that specifies the authentication type under which they become visible. Different color codes are used for different prefixes:
    • Red for Authentication: TLS
    • Purple for Authentication: Static key
    • Blue for Authentication: TLS/Password
  • After changing any of the parameters, don't forget to click the Save & Apply button located at the bottom-right side of the page.

TLS Clients


TLS Clients is a way to differentiate clients by their Common Names (CN), which are found in the client certificate file. It can be used to assign specific VPN addresses to corresponding clients and bind them to their LAN addresses, making the server aware of which client has which LAN IP address.

The TLS Clients section can be found in the OpenVPN Server configuration window, provided that the OpenVPN server uses TLS or TLS/Password authentication methods. To create a new TLS client, type in the new client‘s name in the text field found bellow the TLS Clients tab and click the 'Add' button. Refer to the figure and table below for information on the TLS Clients' configuration fields:

Field Value Description
Endpoint name string; default: none A custom name for the client.
Common name (CN) string; default: none Client’s Common Name (CN) found in the client certificate file.
Virtual local endpoint ip; default: none Client’s local address in the virtual network.
Virtual remote endpoint ip; default: none Client’s remote address in the virtual network.
Private network ip; default: none Client’s private network (LAN) IP address.
Private netmask netmask; default: none Client’s private network (LAN) IP netmask.
Covered Network network(); default: none Selects which networks should be made accessible to this client.


PKCS #12


Enable PKCS #12 format if you wish to use a PKCS #12 archive file format to bundle all the members of a chain of trust instead of uploading certificates separately.

PKCS #12 configuration settings become visible when the Use PKCS #12 format slider is turned on.

Field Value Description
Use PKCS #12 format off | on; default: off Turn PKCS #12 format on or off.
PKCS #12 passphrase string; default: none Passphrase used to decrypt PKCS #12 certificates.
PKCS #12 certificate chain -(interactive button) Use to upload certificate chain file.


OpenVPN Server Brute-force Prevention


OpenVPN Servers with Authentication set to TLS/Password or Password, Protocol set to UDP and running on Port 1194 have a feature where after a client attempts to connect to the server 10 times with incorrect credentials (password and/or username) they are then blocked from the server.

To check which addresses are blocked one first needs to connect to their device's CLI.

After connecting to your device's CLI use the command ipset list and find the section named ipb_port. There under Members you should see all IP addresses that are blocked.

Name: ipb_port
Type: hash:ip,port
Revision: 5
Header: family inet hashsize 1024 maxelem 65536
Size in memory: 164
References: 2
Number of entries: 1
Members:
188.XXX.XXX.XXX,udp:1194

Another way to check blocked IP addresses is to use the command ubus call ip_block show. This will show all ip addresses that failed to connect to your device. If the counter atribute of the IP address entry is larger or equal then max_attempt_count then that IP address is blocked.

{
	"globals": {
		"max_attempt_count": 10
	},
	"ip_blockd 188.XXX.XXX.XXX": {
		"ip": "188.XXX.XXX.XXX",
		"port": "udp:1194",
		"counter": "1"
	},
	"ip_blockd 188.XXX.XXX.XXX": {
		"ip": "188.XXX.XXX.XXX",
		"port": "udp:1194",
		"counter": "10"
	}
}

To unblock a blocked client's IP address use the command ubus call ip_block unblock '{"ip":"<blocked_ip_address>","port":"udp:1194"} (replace <blocked_ip_address> inside the quotes with your blocked IP address). If the IP address was unblocked succesfully you should see a similar response:

{
	"unblocked": {
		"ip": "188.XXX.XXX.XXX",
		"port": "udp:1194"
	}
}

GRE

Generic Routing Encapsulation (GRE) is a tunneling protocol used to establish point-to-point connections between remote private networks. GRE tunnels encapsulate data packets in order to route other protocols over IP networks.

GRE: Main & Tunnel Settings


To create a new GRE instance, go to the Services → VPN → GRE section, enter a custom name and click the 'Add' button. A GRE instance with the given name will appear in the "GRE Configuration" list.

To begin configuration, click the button that looks like a pencil located next to the instance. Refer to the figure and table below for information on the fields located in the GRE instance configuration section.

Field Value Description
Enabled off | on; default: off Turns the GRE instance on or off.
Tunnel source network interface; default: none Network interface used to establish the GRE Tunnel.
Remote endpoint IP address ip; default: none External IP address of another GRE instance used to establish the initial connection between peers.
MTU integer; default: 1476 Sets the maximum transmission unit (MTU) size. It is the largest size of a protocol data unit (PDU) that can be transmitted in a single network layer transaction.
TTL integer [0..255]; default: 255 Sets a custom TTL (Time to Live) value for encapsulated packets. TTL is a field in the IP packet header which is initially set by the sender and decreased by 1 on each hop. When it reaches 0 it is dropped and the last host to receive the packet sends an ICMP "Time Exceeded" message back to the source.
Outbound key integer [0..65535]; default: none A key used to identify outgoing packets. This value should match the "Inbound key" value set on the opposite GRE instance or both key values should be omitted on both sides.
Inbound key integer [0..65535]; default: none A key used to identify incoming packets. This value should match the "Outbound key" value set on the opposite GRE instance or both key values should be omitted on both sides.
Path MTU Discovery off | on; default: on When unchecked, sets the nopmtudisc option for tunnel. Can not be used together with the TTL option.
Keep alive off | on; default: off Turns "keep alive" on or off. The "keep alive" feature sends packets to the remote instance in order to determine the health of the connection. If no response is received, the device will attempt to re-establish the tunnel.
Keep alive interval integer [0..255]; default: none Frequency (in seconds) at which "keep alive" packets are sent to the remote instance.
Local GRE interface IP address ip; default: none IP address of the local GRE Tunnel network interface.
Local GRE interface netmask netmask; default: none Subnet mask of the local GRE Tunnel network interface.

GRE: Routing Settings


Routing settings are used to configure routes to networks that are behind the device that hosts the opposite GRE instance. To add a new route, simply click the 'Add' button. For information on configuring the route refer to the figure and table below.

Field Value Description
Remote subnet IP address ip; default: none IP address of the network behind the device that hosts the remote GRE instance.
Remote subnet netmask netmask; default: none Subnet mask of the network behind the device that hosts the remote GRE instance.

IPsec

To create a new IPsec instance, go to the Services → VPN → IPsec section, enter a custom name and click the 'Add' button. An IPsec instance with the given name will appear in the "IPsec Configuration" list.

IPsec Instance


The general settings section is used to configure the main IPsec parameters. Refer to the figure and table below for information on the configuration fields located in the general settings section.

Field Value Description
Enable off | on; default: off Turns the IPsec instance on or off.
Remote endpoint host | ip; default: none IP address or hostname of the remote IPsec instance.
Authentication method Pre-shared key | X.509 | EAP | PKCS#12; default: Pre-shared key Specify authentication method. Choose between Pre-shared key and X.509 certificates.
PKCS#12: PKCS12 container string; default: none
PKCS#12: PKCS12 decryption passphrase string; default: none
Pre-shared key: Pre shared key string; default: none A shared password used for authentication between IPsec peers before a secure channel is established.
X.509: | EAP: Key A private key file; default: none A private key file.
X.509: | EAP: Key decryption passphrase A password for private key files; default: none If the private key file is encrypted, the passphrase must be defined.
X.509: | EAP: Local Certificate .der file; default: none A local certificate file.
X.509: | EAP: CA Certificate .der file; default: none A certificate authority file.
Local identifier ip | string; default: none Defines how the user (left participant) will be identified during authentication.
  • IP - Internet Protocol address.
  • FQDN - identity defined by fully qualified domain name. It is the complete domain name for a host (for example, something.somedomain.com). Only supported with IKEv2.
Remote identifier ip | string; default: none Defines how the right participant will be identified during authentication.
  • IP - Internet Protocol address.
  • FQDN - identity defined by fully qualified domain name. It is the complete domain name for a host (for example, something.somedomain.com). Only supported with IKEv2.
Multiple secrets off | on; default: off Enable to show Global Secret Settings section for configuring multiple secrets.

Additional notes:

  • Some configuration fields become available only when certain other parameters are selected. The names of the parameters are followed by a prefix that specifies the authentication type under which they become visible. Different color codes are used for different prefixes:
    • Chocolate for Authentication method: Pre-shared key
    • Dark red for Authentication method: X.509/EAP
    • Blue for Authentication method: PKCS#12

Global Secrets Settings


This section is displayed when Multiple secrets is enabled in General settings. You can add new instances by pressing Add.

Field Value Description
ID Selector %any, IP or FQDN; default: none Each secret can be preceded by a list of optional ID selectors. A selector is an IP address, a Fully Qualified Domain Name, user@FQDN or %any. When using IKEv1 use IP address. NOTE: IKEv1 only supports IP address ID selector.
Type PSK | XAUTH | EAP | RSA | PKCS#12; default: PSK IPSec secret type. NOTE: XAUTH secrets are IKEv1 only.
Secret string; default: none A shared password to authenticate between the peers. Minimum length is 5 symbols. All characters are allowed except `.
RSA | PKCS#12: Secret Private key file; default: none A private key file.
RSA | PKCS#12: Key decryption passphrase A password for private key files; default: none If the private key file is encrypted, the passphrase must be defined.

IPsec Instance: Connection Settings


The connection settings section is used to configure the main parameters of an IPsec connection. Refer to the figure and table below for information on the configuration fields located in the connection settings section.

General Settings


Field Value Description
Mode Start | Add | Route; default: Start Specifies which operation will be done automatically at IPSec startup.
Type Tunnel | Transport; default: Tunnel Type of connection.
  • Tunnel - protects internal routing information by encapsulating the entire IP packet (IP header and payload); commonly used in site-to-site VPN connections; supports NAT traversal.
  • Transport - only encapsulates IP payload data; used in client-to-site VPN connections; does not support NAT traversal; usually implemented with other tunneling protocols (for example, L2TP).
Tunnel: Default route off | on; default: off Turn on to route all traffic through IPSec tunnel.
Tunnel: Local subnet ip/netmask | default: none Local IP address and subnet mask used to determine which part of the network can be accessed in the VPN network. Netmask range [0..32]. If left empty, IP address will be selected automatically.
Tunnel: Remote subnet ip/netmask; default: none Remote network IP address and subnet mask used to determine which part of the network can be accessed in the VPN network. Netmask range [0..32]. This value must differ from the device’s LAN IP.
Transport: Bind to GRE interface; L2TP interface; default: none Bind to GRE or L2TP interface to create GRE/L2TP over IPsec.
Key exchange IKEv1 | IKEv2; default: IKEv1 Internet Key Exchange (IKE) version used for key exchange.
  • IKEv1 - more commonly used but contains known issues, for example, dealing with NAT.
  • IKEv2 - updated version with increased and improved capabilities, such as integrated NAT support, supported multihosting, deprecated exchange modes (does not use main or aggressive mode; only 4 messages required to establish a connection).
Enable XAuth on | off; default: off Enables Extended Authentication.

Additional notes:

  • Some configuration fields become available only when certain other parameters are selected. The names of the parameters are followed by a prefix that specifies the authentication type under which they become visible. Different color codes are used for different prefixes:
    • Red for Type: Tunnel
    • Purple for Type: Transport

Advanced settings


Field Value Description
Aggressive off | on; default: off Turn aggressive mode on or off for outgoing connections. Aggressive mode performs fewer exchanges (a total of 4 messages) than Main mode (a total of 6 messages) by storing most data into the first exchange. In aggressive mode, the information is exchanged before there is a secure channel, making it less secure but faster than main mode.
Aggressive mode is available only with IKEv1; if IKEv2 is selected this field becomes hidden.
Force encapsulation off | on; default: off Forces UDP encapsulation for ESP packets even if a "no NAT" situation is detected.
Local firewall off | on; default: on Adds necessary firewall rules to allow traffic of this IPsec instance on this device.
Remote firewall off | on; default: on Adds necessary firewall rules to allow traffic of from the opposite IPsec instance on this device.
Compatibility mode off | on; default: off Turns on compatibility mode to help deal with a 3rd party remote peer with multiple subnets.
Inactivity integer; default: none Defines timeout interval, after which a CHILD_SA is closed if it did not send or receive any traffic.
Dead Peer Detection off | on; default: off A function used during Internet Key Exchange (IKE) to detect a "dead" peer. It used to reduce traffic by minimizing the number of messages when the opposite peer in unavailable and as failover mechanism.
Dead Peer Detection: DPD action Restart | Hold | Clear | None; default: Restart Controls the use of the Dead Peer Detection protocol where notification messages are periodically sent in order to check the liveliness of the IPsec peer.
Dead Peer Detection: DPD Delay integer; default: none The frequency of sending R_U_THERE messages or INFORMATIONAL exchanges to peer.
Dead Peer Detection: DPD Timeout integer; default: none Defines the timeout interval, after which all connections to a peer are deleted in case of inactivity.
XAuth identity string; default: none The identity/username the client uses to reply to an XAuth request. If not defined, the IKEv1 identity will be used as XAuth identity.
Tunnel: Remote source IP ip; default: none The internal source IP to use in a tunnel for the remote (right) peer.
Tunnel: Local source IP ip; default: none The internal (left) source IP to use in a tunnel, also known as virtual IP.
Tunnel: Remote DNS ip; default: none List of DNS server addresses to exchange as configuration attributes. On the responder, only fixed IPv4/IPv6 addresses are allowed and define DNS servers assigned to the client.
Locally allowed protocols string; default: none Allowed protocols and ports over connection, also called Port Selectors. Defines in form of 'protocol/port' eg:'17/1701' or '17/%any' or 'udp/l2f'.
Remotely allowed protocols string; default: none Allowed protocols and ports over connection, also called Port Selectors. Defines in form of 'protocol/port' eg:'17/1701' or '17/%any' or 'udp/l2f'.
Custom option string; default: none Add custom connection parameters.
Local source IP ip; default: none The internal (left) source IP to use in a tunnel, also known as virtual IP.
Tunnel: Passthrough interfaces network interfaces; default: none Network interfaces to include in IPsec Passthrough.
Tunnel: Passthrough subnets ip/netmask; default: none Networks to include in IPsec Passthrough.

Additional notes:

  • Some configuration fields become available only when certain other parameters are selected. The names of the parameters are followed by a prefix that specifies the authentication type under which they become visible. Different color codes are used for different prefixes:
    • Red for Type: Tunnel
    • Blue for Dead Peer Detection: Enabled

IPsec instance: proposal settings


The proposal settings section is used to configure IKE (Internet Key Exchange) phase 1 & 2 settings. IKE is a protocol used to set up security associations (SAs) for the IPsec connection. This process is required before any IPsec tunnel can be established. It is done in two phases:

Phase Mode
Phase 1
  • Establishes a secure channel between peers
  • Authenticates peers
  • Negotiates SA policy
  • Shares secret keys
  • Establishes secure tunnel for phase 2
Main mode (figure 1)
  • 6 packets exchanged
  • Identity protected during exchange
Aggressive mode (figure 2)
  • 3 packets exchanged
  • Identity information exchanged before a secure channel is established
Phase 2
  • Sets up matching IPsec SAs
  • Periodically renegotiates IPsec SAs
Quick mode
  • 3 packets exchanged
  • IPsec SA parameters (ESP/AH, SHA/MD5) established
  • SA lifetime set


Figure 1

Figure 2

Phase 1


Field Value Description
Encryption algorithm 3DES | AES 128 | AES 192 | AES 256 | AES128 GCM8 | AES192 GCM8 | AES256 GCM8 | AES128 GCM12 | AES192 GCM12 | AES256 GCM12 | AES128 GCM16 | AES192 GCM16 | AES256 GCM16; default: AES 128 Algorithm used for data encryption.
Authentication MD5 | SHA1 | SHA256 | SHA384 | SHA512; default: SHA1 Algorithm used for exchanging authentication and hash information.
DH group MODP768 | MODP1024 | MODP1536 | MODP2048 | MODP3072 | MODP4096 | ECP192 | ECP224 | ECP256 | ECP384 | ECP521 | No PFS; default: MODP1536 Diffie-Hellman (DH) group used in the key exchange process. Higher group numbers provide more security, but take longer and use more resources to compute the key. Must match with another incoming connection to establish IPSec.
Force crypto proposal off | on; default: off Only chosen proposals will be used when turned on.
IKE Lifetime string; default: none How long the keying channel of a connection (ISAKMP or IKE SA) should last before being renegotiated. The time is specified in seconds. The s, m, h and d suffixes explicitly define the units for seconds, minutes, hours and days, respectively.

Phase 2


Field Value Description
Encryption algorithm 3DES | AES 128 | AES 192 | AES 256 | AES128 GCM8 | AES192 GCM8 | AES256 GCM8 | AES128 GCM12 | AES192 GCM12 | AES256 GCM12 | AES128 GCM16 | AES192 GCM16 | AES256 GCM16; default: 3DES Algorithm used for data encryption.
Hash algorithm MD5 | SHA1 | SHA256 | SHA384 | SHA512; default: MD5 Algorithm used for exchanging authentication and hash information.
PFS group MODP768 | MODP1024 | MODP1536 | MODP2048 | MODP3072 | MODP4096 | ECP192 | ECP224 | ECP256 | ECP384 | ECP521 | No PFS; default: MODP768 The PFS (Perfect Forward Secrecy). Must match with another incoming connection to establish IPSec.
Force crypto proposal off | on; default: off Only chosen proposals will be used when turned on.
Lifetime string; default: none How long the keying channel of a connection (ISAKMP or IKE SA) should last before being renegotiated. The time is specified in seconds. The s, m, h and d suffixes explicitly define the units for seconds, minutes, hours and days, respectively.

PPTP

Point-to-Point Tunneling Protocol (PPTP) is a type of VPN protocol that uses a TCP control channel and a Generic Routing Encapsulation tunnel to encapsulate PPP packets.

PPTP client


A PPTP client is an entity that initiates a connection to a PPTP server. To create a new client instance, go to the Services → VPN → PPTP section, select Role: Client, enter a custom name and click the 'Add' button:

You should be redirected to the configuration page for the newly added PPTP Client which should look similar to this:

Field Value Description
Enable off | on; default: off Turns the PPTP instance on or off.
Server ip | host; default: none IP address or hostname of a PPTP server.
Username string; default: none Username used for authentication to the PPTP server.
Password string; default: none Password used for authentication to the PPTP server.
Client to client off | on; default: off Adds route to make other PPTP clients reachable.
Default route off | on; default: off When turned on, this connection will become the device default route. This means that all traffic directed to the Internet will go through the PPTP server and the server's IP address will be seen as this device's source IP to other hosts on the Internet.

PPTP server


A PPTP server is an entity that waits for incoming connections from PPTP clients. To create a new server instance, go to the Services → VPN → PPTP section, select Role: Server, enter a custom name and click the 'Add' button:

You should be redirected to the configuration page for the newly added PPTP Server which should look similar to this:

Field Value Description
Enable off | on; default: off Turns the PPTP instance on or off.
Local IP ip; default: 192.168.0.1 IP address of this PPTP network interface.
Remote IP range start ip; default: 192.168.0.20 PPTP IP address leases will begin from the address specified in this field.
Remote IP range end ip; default: 192.168.0.30 PPTP IP address leases will end with the address specified in this field.
Timeout integer; default: none Time in seconds. If no packets pass through the tunnel between this server and a client, the server will terminate the connection to that client after the amount of time specified in this field passes.
Primary DNS ip; default: none IP address of the primary DNS server.
Secondary DNS ip; default: none IP address of the secondary DNS server.

The User List section is used to keep authentication settings required to successfully connect to this server. The list is empty by default. Click the 'Add' button to create a new PPTP User:

Field Value Description
Username string; default: none Username used for authentication to this PPTP server.
Password string; default: none Password used for authentication to this PPTP server.
PPTP Client's IP ip; default: none Assigns an IP address to the client that uses the adjacent authentication info. This field is optional and if left empty the client will simply receive an IP address from the IP pool defined above.

Note: there can only be one PPTP Server configuration on the device.

SSTP

Secure Socket Tunneling Protocol (SSTP) is a VPN protocol designed to transport PPP traffic via a secure SSL/TLS channel.
Note: SSTP is additional software that can be installed from the System → Package Manager page.

SSTP configuration


To create a new SSTP instance, go to the Services → VPN → SSTP section, enter a custom name and click the 'Add' button. An SSTP instance with the given name will appear in the "SSTP Configuration" list.

To begin configuration, click the 'Edit' button located next to the instance. Refer to the figure and table below for information on the SSTP instance's configuration fields:

Field Value Description
Enable off | on; default: off Turns the SSTP instance on or off.
Server IP address ip | host; default: none IP address or hostname of a SSTP server.
User name string; default: none Username used for authentication to the SSTP server.
Password string; default: none Password used for authentication to the SSTP server.
Certificate files from device off | on; default: off Turn on this option if you want to select generated certificate files from device.
CA cert .crt file; default: none Upload a Certificate authority (CA) file.
Default route off | on; default: off When turned on, this connection will become the device default route. This means that all traffic directed to the Internet will go through the SSTP server and the server's IP address will be seen as this device's source IP to other hosts on the Internet.
NOTE: this can only be used when Failover is turned off.

Stunnel

Stunnel is an open-source a proxy service that adds TLS encryption to clients and servers already existing on a VPN network. TLS encryption provided by Stunnel can be used as an additional layer of encryption for data sent by VPN. This procedure increases the security of the established connection and provides higher chances of passing a Deep packet inspection (DPI) check.

Stunnel globals


The Stunnel Globals section is used to manage the Stunnel service as a whole. Refer to the figure and table below for information on the fields contained in the Stunnel Globals section.
Note: Stunnel is additional software that can be installed from the System → Package Manager page.

Field Value Description
Enabled off | on; default: off Turns the Stunnel service on or off. If this is unchecked, Stunnel instances will not start (even if they are enabled individually); therefore, it is necessary to check this field in order to make Stunnel active on the router.
Debug Level integer [0..7]; default: 5 Debugging to log output level.
  • 0 (emergency) - a panic condition, i.e., system is no longer usable.
  • 1 (alert) - a condition that must be corrected immediately.
  • 2 (critical) - critical conditions, device errors.
  • 3 (error) - errors that are fatal to the operation, but not the service or application (can't open a required file, missing data, etc.) Solving these types of errors will usually require user intervention.
  • 4 (warning) - anything that can potentially cause application oddities, but for which the system is automatically recovering from (e.g., retrying an operation, missing secondary data, etc.)
  • 5 (notice) - conditions that are not error conditions, but that may require special handling.
  • 6 (info) - general useful information (e.g., configuration changes, starts and stops of services, etc.)
  • 7 (debug) - contains basic information that is diagnostically helpful to most people (i.e., not just engineers).
Use alternative config off | on; default: off Turns the possibility to upload an external Stunnel configuration file on or off.if you turn this on, other Stunnel configurations present in the router will become inactive.
Upload alternative config file; default: none Uploads an Stunnel configuration file.

Stunnel instance


To create a new Stunnel instance, go to the Services → VPN → Stunnel section, enter a custom name and click the 'Add' button. An Stunnel instance with the given name will appear in the "Stunnel Configuration" list.

To begin configuration, click the 'Edit' button located next to the instance. Refer to the figure and table below for information on the Stunnel instance's configuration fields:

Field Value Description
Enable off | on; default: off Turns the Stunnel instance on or off.
Operating Mode Server | Client; default: Server Selects the Stunnel instance's role.
  • Server - listens for connecting Stunnel clients.
  • Client - listens for connecting clients and connects to an Stunnel server.
Listen IP ip; default: none Makes the instance "listen" for incoming connections on the specified IP address. When left empty, the value of this field defaults to localhost (127.0.0.1).
Listen Port integer [0..65535]; default: none Makes the instance "listen" for incoming connections on the specified TCP port. Make sure you chose a port that is not being used by another service. You will also have to allow traffic on the specified port.
Connect IP's ip:port; default: none IP:Port to listen for VPN connections. When left empty the value of this field is interpreted as localhost. Must contain at least one item. If multiple options are specified, remote address is chosen using a round-robin algorithm.
TLS Cipher None | Secure | Custom; default: None Packet encryption algorithm cipher.
Custom: Allowed TLS Ciphers string; default: none A list of TLS ciphers accepted for this connection.
Application Protocol Connect | SMTP | Not specified; default: Not specified This option enables initial, protocol-specific negotiation of the TLS encryption. The protocol option should not be used with TLS encryption on a separate port.
Connect: Protocol Authentication Basic | NTLM; default: Basic Authentication type for the protocol negotiations.
SMTP: Protocol Authentication Plain | Login; default: Plain Authentication type for the protocol negotiations.
Certificate File .crt file; default: none TLS client or server certificate file.
Private Key .key file; default: none TLS client or server key file.

Additional notes:

  • Some configuration fields become available only when certain other parameters are selected. The names of the parameters are followed by a prefix that specifies the authentication type under which they become visible. Different color codes are used for different prefixes:
    • Blue for TLS Cipher: Custom
    • Dark red for Application Protocol: Connect
    • Chocolate for Application Protocol: SMTP

DMVPN

Dynamic Multipoint VPN (DMVPN) is a method of building scalable IPsec VPNs. DMVPN is configured as a hub-and-spoke network, where tunnels between spokes are built dynamically; therefore, no change in configuration is required on the hub in order to connect new spokes.
Note: DMPVN is additional software that can be installed from the System → Package Manager page.

DMVPN configuration


To create a new DMVPN instance, go to the Services → VPN → DMVPN section, enter a custom name and click the 'Add' button. A DMVPN instance with the given name will appear in the "DMVPN Configuration" list.

To begin configuration, click the button that looks like a pencil located next to the instance. Refer to the figures and tables below for information on the DMVPN instance configuration:

Field Value Description
Enabled off | on; default: off Turns the DMVPN instance on or off.
Working mode Spoke | Hub; default: Spoke Selects the role of this instance
  • Hub - the central instance of DMVPN that connects other peers (spokes) into single network. There is no need to reconfigure the hub when connecting new spokes to it.
  • Spoke - an instance that connects to the hub.
Hub address ip | host; default: none IP address or hostname of a DMVPN hub.



Field Value Description
Tunnel source network interface; default: Any Network interface used to establish the GRE Tunnel.
Local GRE interface IP address ip; default: none IP address of the local GRE Tunnel instance.
Spoke: Remote GRE interface IP address ip; default: none IP address of the remote GRE Tunnel instance.
Hub: Local GRE interface netmask netmask; default: none Subnet mask of the local GRE Tunnel instance.
GRE MTU integer; default: 1476 Sets the maximum transmission unit (MTU) size. It is the largest size of a protocol data unit (PDU) that can be transmitted in a single network layer transaction.
Outbound key integer [0..65535]; default: none A key used to identify outgoing GRE packets. This value should match the Inbound key value set on the opposite GRE tunnel instance or both key values should be omitted on both sides.
Inbound key integer [0..65535]; default: none A key used to identify incoming GRE packets. This value should match the Outbound key value set on the opposite GRE instance or both key values should be omitted on both sides.



Field Value Description
Local identifier ip | string; default: none Defines how the user (IPsec instance) will be identified during authentication.
  • IP - Internet Protocol address.
  • FQDN - identity defined by fully qualified domain name. It is the complete domain name for a host (for example, something.somedomain.com). Only supported with IKEv2.
Remote identifier ip | string; default: none Defines how the right participant will be identified during authentication.
  • IP - Internet Protocol address.
  • FQDN - identity defined by fully qualified domain name. It is the complete domain name for a host (for example, something.somedomain.com). Only supported with IKEv2.
Pre-shared key string; default: none A shared password used for authentication between IPsec peers.
Encryption algorithm 3DES | AES 128 | AES 192 | AES 256 | AES128 GCM8 | AES192 GCM8 | AES256 GCM8 | AES128 GCM12 | AES192 GCM12 | AES256 GCM12 | AES128 GCM16 | AES192 GCM16 | AES256 GCM16; default: AES 128 Algorithm used for data encryption.
Authentication/Hash algorithm MD5 | SHA1 | SHA256 | SHA384 | SHA512; default: SHA1 Algorithm used for exchanging authentication and hash information.
DH/PFS group MODP768 | MODP1024 | MODP1536 | MODP2048 | MODP3072 | MODP4096 | ECP192 | ECP224 | ECP256 | ECP384 | ECP521; default: MODP1536 Diffie-Hellman (DH) group used in the key exchange process. Higher group numbers provide more security, but take longer and use more resources to compute the key. Must match with another incoming connection to establish IPSec.
Force crypto proposal off | on; default: off Only chosen proposals will be used when turned on.
IKE Lifetime string; default: none How long the keying channel of a connection (ISAKMP or IKE SA) should last before being renegotiated. The time is specified in seconds. The s, m, h and d suffixes explicitly define the units for seconds, minutes, hours and days, respectively.



Field Value Description
NHRP network ID integer; default: 1 An identifier used to define the NHRP domain. This is a local parameter and its value does not need to match the values specified on other domains. However, the NHRP ID is added to packets which arrive on the GRE interface; therefore, it may be helpful to use the same ID for troubleshooting purposes.
NHRP authentication key string; default: none A key used in NHRP authentication.
NHRP hold time integer; default: 7200 Specifies the holding time for NHRP Registration Requests and Resolution Replies sent from this interface or shortcut-target. The hold time is specified in seconds and defaults to two hours.
Redirect off | on; default: off Enables or disables DMVPN traffic redirection.
Hub: NFLOG group integer [1..65535]; default: none Specify NFLOG group to be used by NHRP instance

L2TP

In computer networking, Layer 2 Tunneling Protocol (L2TP) is a tunneling protocol used to support virtual private networks (VPNs). It is more secure than PPTP but, because it encapsulates the transferred data twice, but it is slower and uses more CPU power.

L2TP client


An L2TP client is an entity that initiates a connection to an L2TP server. To create a new client instance, go to the Services → VPN → L2TP section, select Role: Client, enter a custom name and click the 'Add' button. An L2TP client instance with the given name will appear in the "L2TP Configuration" list.

To begin configuration, click the button that looks like a pencil next to the client instance. Refer to the figure and table below for information on the L2TP client's configuration fields:

Field Value Description
Enable off | on; default: off Turns the L2TP instance on or off.
Server ip | host; default: none IP address or hostname of an L2TP server.
Username string; default: none Username used for authentication to the L2TP server.
Password string; default: none Password used for authentication to the L2TP server.
CHAP secret string; default: none A secret used for L2TP Tunnel Authentication.
MTU [68..9200]; default: none Sets the maximum transmission unit (MTU) size. It is the largest size of a protocol data unit (PDU) that can be transmitted in a single network layer transaction.
Default route off | on; default: off When turned on, this connection will become device default route. This means that all traffic directed to the Internet will go through the L2TP server and the server's IP address will be seen as this device's source IP to other hosts on the Internet.
Allow CHAP on | off; default: on Allows CHAP authentication method to be used.
Allow PAP on | off; default: off Allows PAP authentication method to be used.
Allow MSCHAP-v2 on | off; default: on Allow MSCHAP-v2 authentication method to be used.


Active L2TP client instance example:


L2TP server


An L2TP server is an entity that waits for incoming connections from L2TP clients. To create a new server instance, go to the Services → VPN → L2TP section, select Role: Server, enter a custom name and click the 'Add' button. An L2TP server instance with the given name will appear in the "L2TP Configuration" list. Only one L2TP server instance is allowed to be added.

A server needs to have a public IP address in order to be available from the public network (the Internet).

To begin configuration, click the button that looks like a pencil next to the server instance. Refer to the figure and table below for information on the L2TP server's configuration fields:

Field Value Description
Enable off | on; default: off Turns the L2TP instance on or off.
Local IP ip; default: 192.168.0.1 IP address of this L2TP network interface.
Remote IP range begin ip; default: 192.168.0.20 L2TP IP address leases will begin from the address specified in this field.
Remote IP range end ip; default: 192.168.0.30 L2TP IP address leases will end with the address specified in this field.
Enable CHAP on | off; default: off Challenge-Handshake Authentication Protocol for L2TP.
CHAP authentication on | off; default: on When turned on it requires CHAP authentication method to be used, when turned off it refuses CHAP authentication method.
PAP authentication on | off; default: off When turned on it requires PAP authentication method to be used, when turned off it refuses PAP authentication method.
MSCHAP-v2 authentication on | off; default: on When turned on it requires MSCHAP-v2 authentication method to be used, when turned off it refuses MSCHAP-v2 authentication method.
User name string; default: user Username used for authentication to this L2TP server.
Password string; default: pass Password used for authentication to this L2TP server.
L2TP Client's IP ip; default: none Assigns an IP address to the client that uses the adjacent authentication info. This field is optional and if left empty the client will simply receive an IP address from the IP pool defined above.


Active L2TP server instance example:


L2TPv3

L2TPv3 (Layer Two Tunneling Protocol Version 3) is a point-to-point layer two over IP tunnel. This means you can tunnel L2 protocols like Ethernet, Frame-relay, ATM, HDLC, PPP, etc. over an IP network.

Local settings


Field Value Description
Enable off | on; default: off Turns the L2TPv3 instance on or off.
Local address ip; default: none IP address of device's WAN. Note: If left empty, it will take IP address automatically from main WAN interface.
Tunnel ID integer [1..4294967295]; default: none Uniquely identifies the tunnel. The value used must match the peer tunnel ID value being used at the peer.
Session ID integer [1..4294967295]; default: none The value used must match the tunnel ID value being used at the peer.
Cookie string; default: none Must be specified in hexidecimal form and be length of 8 or 16. eg.: 89ABCDEF.

Peer settings


Field Value Description
Peer address ip; default: none Peer Endpoint IP address.
Peer Tunnel ID integer [1..4294967295]; default: none ID of peer's tunnel is specified from 1 to 4294967295. It must match other end tunnel ID.
Peer Session ID integer [1..4294967295]; default: none UID of peer's session is specified from 1 to 4294967295. It must match other end session ID.
Peer Cookie string; default: none Must be specified in hexidecimal form and be length of 8 or 16. eg.: 89ABCDEF. It must match other end Cookie.

Instance Settings


Field Value Description
Bridge to None | LAN; default: None Peer Endpoint IP address.
IP Address ip; default: none IP address of standalone L2TPv3 interface.
Netmask netmask; default: none Netmask of standalone L2TPv3 interface.
MTU integer [64..9000]; default: none Sets the maximum transmission unit (MTU) size. It is the largest size of a protocol data unit (PDU) that can be transmitted in a single network layer transaction.
Encapsulation IP | UDP; default: IP Specify technology to use when connecting to other end.
Layer 2 specific header type None | Linux Default; default: Linux Default It might be neccessary to set this option to none when using other hardware.

ZeroTier

ZeroTier One is an open source software which can establish Peer to Peer VPN (P2PVPN) connection between various devices running various operating systems. It also provides network management possibilities such as routing and creating firewall rules.

Note: ZeroTier is additional software that can be installed from the System → Package Manager page.


In order to create a new ZeroTier Instance, look to the Add New ZeroTier Configuration section; enter a custom name and click the 'Add' button:


You should be redirected to the configuration page for the newly added ZeroTier Instance which should look similar to this:

Field Value Description
Enabled off | on; default: off Turns the ZeroTier Instance on or off.


ZeroTier network configuration instance should look similar to this:

Field Value Description
Enabled off | on; default: off Turns the ZeroTier Instance on or off.
Port integer [0..65535]; default: 9993 ZeroTier Network port.
Network ID hex string; default: none ZeroTier Network ID. Log in to your ZeroTier account in order to locate the ZeroTier Network ID, which should be a string of hexadecimal characters.
Bridge to None | LAN; default: None Specify to which interface this ZeroTier instance should be bridged to.
Allow default route off | on; default: off Allows ZeroTier to override system default route
Allow global IP off | on; default: off Allows ZeroTier managed IPs and routes to overlap public IP space
Allow managed IP off | on; default: on Assigns ZeroTier managed IPs and routes
Allow DNS off | on; default: off Applies DNS servers that are set at the network controller

WireGuard

WireGuard is simple, fast, lean, and modern VPN that utilizes secure and trusted cryptography. It intends to be more performant than OpenVPN. WireGuard is designed as general purpose VPN, fit for many different circumstances and while it is currently under heavy development, it already might be regarded as the most secure, easiest to use, and simplest VPN solution.

WireGuard works by adding an interface which acts as a tunnel. To create one enter its name and click the Add button. This should add a new Wireguard instance and open a configuration window.

General Instance Settings


This section contains General settings of created WireGuard Instance. Here you can find its Public and Private keys and generate them, specify Port and IP addresses for communication.

Field Value Description
Enable off | on; default: off Turns WireGuard Instance on or off.
Private Key string; default: none Private Key used in authentication.
Public Key string; default: - Public Key used in authentication.
Generate -(interactive button) Click to generate Public Key and Private Key.
Listen Port integer [0..65535]; default: none Specify port to listen for incomming connections. It will be set to a random integer if left empty.
IP Addresses ip; default: none A single IP address or a list of them for this instance associated with public keys.


Advanced Settings


Advanced Settings section contains Metric and MTU configuration for this WireGuard interface.

Field Value Description
Metric positive integer; default: none Specify metric for this tunnel interface. Lower number means higher priority.
MTU integer [1280..1420]; default: none Maximum Transmission Unit for this tunnel interface.
DNS servers ip | ips; default: none DNS server(s) for this Wireguard interface.


Peers


The Peers section is used to create and configure all the peers for this interface. To create one enter its name and click the Add button. To configure it click the Edit button.


General Peer Settings


In the General section of Peer instance you can configure basic information about the endpoint to allow communications.

Field Value Description
Public Key string; default: none Endpoint's Public Key.
Allowed IPs ip; default: none A single IP address or a list of them which are allowed to communicate with this peer.
Description string; default: none Description of the peer.
Route Allowed IPs off | on; default: off Enable to create routes for Allowed IPs for this peer.


Advanced Peer Settings


In the Advanced section of Peer instance you are able to configure additional settings such as its Description, Endpoint Host and Port, Preshared Key and other. See more information below.

Field Value Description
Description string; default: none Description of this peer.
Pre-Shared Key string; default: none Base64-encoded preshared key. Adds in an additional layer of symmetric-key cryptography for post-quantum resistance.
Route Allowed IPs off | on; default: off Enable to create routes for Allowed IPs for this peer.
Endpoint Host ip | url; default: none IP or URL of Remote Endpoint.
Endpoint Port integer [0..65535]; default: none Specify port to connect to Remote Endpoint. It will be set to 51820 if left empty.
Persistent Keep Alive integer [0..65535]; default: none Specify time amount in seconds between Keep Alive messages. By default this option is 0 which means it is disabled. Recommended value for a device behind NAT is 25.

Tinc

Tinc is a Virtual Private Network (VPN) daemon that uses tunnelling and encryption to create a secure private network between hosts on the Internet. Tinc is Free Software and licensed under the General Public License version 2 or later. Because the VPN appears to the IP level network code as a normal network device, there is no need to adapt any existing software. This allows VPN sites to share information with each other over the Internet without exposing any information to others.

Tinc works by adding an interface which acts as Router/Switch/Hub mode. To create one enter its name and click the Add button. This should add a new Tinc interface and open a configuration window

General Interface Settings


This section contains General settings of created Tinc Interface. Here you can find its Public and Private keys, specify Subnet and Host to Connect to for communication.

Field Value Description
Enable off | on; default: off Turns Tinc Interface on or off.
Subnet ip; default: none The subnet which this tinc daemon will serve. Multiple subnet lines can be specified for each Daemon.
Private Key .key file; default: none Generated RSA private key.
Public Key .key file; default: none Generated RSA public key.
Host to Connect to Not specified | Host name; default: Not specified Specifies which other tinc daemon to connect to on startup. Multiple variables may be specified, in which case outgoing connections to each specified tinc daemon are made.


Advanced Settings


Advanced Settings section.

Field Value Description
Address Family Any | IPv4 | IPPv6; default: Any This option affects the address family of listening and outgoing sockets.
Bind To Address ip; default: none Addresses for Tinc VPN to use for listening sockets.
Bind To Interface Any | LAN | WAN | WAN6 | Mobile; default: Any Interface to listen for incoming connections.
Key Expire integer; default: 3600 This option controls the time the encryption keys used to encrypt the data are Valid.
Mode Router | Switch | Hub; default: Router This option selects the way packets are routed to other daemons.
Ping Interval integer; default: 60 The number of seconds of inactivity that tinc will wait before sending a probe to the other end.
Ping Timeout integer; default: 5 The number of seconds to wait for a response to pings or to allow meta connections to block. If the other end doesn't respond within this time, the connection is terminated, and the others will be notified of this.


Hosts


The Hosts section is used to add your VPN hosts. To create one enter its name and click the Add button. To configure it click the Edit button.


General Tinc Host Settings


In the General section of Hosts instance you can configure basic information about the host.

Field Value Description
Enable off | on; default: off Turn this tinc host on/off.
Description string; default: none Optional. Description of host.
Address ip; default: none It must resolve to the external IP address where the host can be reached, not the one that is internal to the VPN.
Subnet ip; default: none The subnet which this tinc daemon will serve. Multiple subnet lines can be specified for each Daemon.
Public Key .key file; default: none Generated RSA public key.