Chapter 12. Setting up a WireGuard VPN by using the RHEL web console

1. WireGuard reads the destination IP from the packet and compares it to the list of allowed IP addresses in the local configuration. If the peer is not found, WireGuard drops the packet.
2. If the peer is valid, WireGuard encrypts the packet using the peer’s public key.
3. The sending host looks up the most recent Internet IP address of the host and sends the encrypted packet to it.

1. WireGuard decrypts the packet using the private key of the remote host.
2. WireGuard reads the internal source address from the packet and looks up whether the IP is configured in the list of allowed IP addresses in the settings for the peer on the local host. If the source IP is on the allowlist, WireGuard accepts the packet. If the IP address is not on the list, WireGuard drops the packet.

Procedure

1. Select the Networking tab in the navigation on the left side of the screen.
2. Click Add VPN in the Interfaces section.
3. If the wireguard-tools and systemd-resolved packages are not already installed, the web console displays a corresponding notification. Click Install to install these packages.
4. Enter the name of the WireGuard device that you want to create.

5. Configure the key pair of this host:

   • If you want use the keys that the web console has created:

     1. Keep the pre-selected Generated option in the Private key area.
     2. Note the Public key value. You require this information when you configure the client.

   • If you want to use an existing private key:

     1. Select Paste existing key in the Private key area.
     2. Paste the private key into the text field. The web console automatically calculates the corresponding public key.

6. Set a listen port number, such as 51820, for incoming WireGuard connections.

   Always set a fixed port number on hosts that receive incoming WireGuard connections. If you do not set a port, WireGuard uses a random free port each time you activate the interface.

7. Set the tunnel IPv4 address and subnet mask of the server.

   To also set an IPv6 address, you must edit the connection after you have created it.

8. Add peer configurations for each client that you want to allow to communicate with this server:

   1. Click Add peer.
   2. Enter the public key of the client.
   3. Leave the Endpoint field empty.
   4. Set the Allowed IPs field to the tunnel IP addresses of the clients that are allowed to send data to this server.
   
9. Click Add to create the WireGuard connection.

10. If you want to also set a tunnel IPv6 address:

    1. Click on the WireGuard connection’s name in the Interfaces section.
    2. Click edit next to IPv6.
    3. Set the Addresses field to Manual, and enter the tunnel IPv6 address and prefix of the server.
    4. Click Save.

Verification

1. Display the interface configuration of the wg0 device:

   # wg show wg0
   interface: wg0
     public key: UtjqCJ57DeAscYKRfp7cFGiQqdONRn69u249Fa4O6BE=
     private key: (hidden)
     listening port: 51820
   
   peer: bnwfQcC8/g2i4vvEqcRUM2e6Hi3Nskk6G9t4r26nFVM=
     allowed ips: 192.0.2.2/32, 2001:db8:1::2/128

   To display the private key in the output, use the WG_HIDE_KEYS=never wg show wg0 command.

2. Display the IP configuration of the wg0 device:

   # ip address show wg0
   20: wg0: <POINTOPOINT,NOARP,UP,LOWER_UP> mtu 1420 qdisc noqueue state UNKNOWN group default qlen 1000
       link/none
       inet 192.0.2.1/24 brd 192.0.2.255 scope global noprefixroute wg0
          valid_lft forever preferred_lft forever
       inet6 2001:db8:1::1/32 scope global noprefixroute
          valid_lft forever preferred_lft forever
       inet6 fe80::3ef:8863:1ce2:844/64 scope link noprefixroute
          valid_lft forever preferred_lft forever

Procedure

1. Select the Networking tab in the navigation on the left side of the screen.
2. Click Edit rules and zones in the Firewall section.
3. Enter wireguard into the Filter services field.

4. Select the wireguard entry from the list.

   
5. Click Add services.

6. If clients should route all traffic through the tunnel and use the WireGuard server as the default gateway, enable masquerading for the public zone:

   # firewall-cmd --permanent --zone=public --add-masquerade
   # firewall-cmd --reload

   Note that you cannot enable masquerading in firewalld zones in the web console.

Verification

1. Select the Networking tab in the navigation on the left side of the screen.
2. Click Edit rules and zones in the Firewall section.
3. The list contains an entry for the wireguard service and displays the UDP port that you configured in the WireGuard connection profile.

4. To verify that masquerading is enabled in the firewalld public zone, enter:

   # firewall-cmd --list-all --zone=public
   public (active)
     ...
     ports: 51820/udp
     masquerade: yes
     ...

Procedure

1. Select the Networking tab in the navigation on the left side of the screen.
2. Click Add VPN in the Interfaces section.
3. If the wireguard-tools and systemd-resolved packages are not already installed, the web console displays a corresponding notification. Click Install to install these packages.
4. Enter the name of the WireGuard device that you want to create.

5. Configure the key pair of this host:

   • If you want use the keys that the web console has created:

     1. Keep the pre-selected Generated option in the Private key area.
     2. Note the Public key value. You require this information when you configure the client.

   • If you want to use an existing private key:

     1. Select Paste existing key in the Private key area.
     2. Paste the private key into the text field. The web console automatically calculates the corresponding public key.
6. Preserve the 0 value in the Listen port field.

7. Set the tunnel IPv4 address and subnet mask of the client.

   To also set an IPv6 address, you must edit the connection after you have created it.

8. Add a peer configuration for the server that you want to allow to communicate with this client:

   1. Click Add peer.
   2. Enter the public key of the server.
   3. Set the Endpoint field to the hostname or IP address and the port of the server, for example server.example.com:51820. The client uses this information to establish the connection.

   4. Set the Allowed IPs field to the tunnel IP addresses of the clients that are allowed to send data to this server. For example, set the field to one of the following:

      • The tunnel IP addresses of the server to allow only the server to communicate with this client. The value in the screen capture below configures this scenario.
      • 0.0.0.0/0 to allow any remote IPv4 address to communicate with this client. Use this setting to route all traffic through the tunnel and use the WireGuard server as default gateway.
   
9. Click Add to create the WireGuard connection.

10. If you want to also set a tunnel IPv6 address:

    1. Click on the WireGuard connection’s name in the Interfaces section.
    2. Click edit next to IPv6.
    3. Set the Addresses field to Manual, and enter the tunnel IPv6 address and prefix of the client.
    4. Click Save.

Verification

1. Ping the IP addresses of the server:

   # ping 192.0.2.1

   WireGuard establishes the connection when you try to send traffic through the tunnel.

2. Display the interface configuration of the wg0 device:

   # wg show wg0
   interface: wg0
     public key: bnwfQcC8/g2i4vvEqcRUM2e6Hi3Nskk6G9t4r26nFVM=
     private key: (hidden)
     listening port: 45513
   
   peer: UtjqCJ57DeAscYKRfp7cFGiQqdONRn69u249Fa4O6BE=
     endpoint: server.example.com:51820
     allowed ips: 192.0.2.1/32, 2001:db8:1::1/128
     latest handshake: 1 minute, 41 seconds ago
     transfer: 824 B received, 1.01 KiB sent
     persistent keepalive: every 20 seconds

   To display the private key in the output, use the WG_HIDE_KEYS=never wg show wg0 command.

   Note that the output has only the latest handshake and transfer entries if you have already sent traffic through the VPN tunnel.

3. Display the IP configuration of the wg0 device:

   # ip address show wg0
   10: wg0: <POINTOPOINT,NOARP,UP,LOWER_UP> mtu 1420 qdisc noqueue state UNKNOWN group default qlen 1000
       link/none
       inet 192.0.2.2/24 brd 192.0.2.255 scope global noprefixroute wg0
          valid_lft forever preferred_lft forever
       inet6 2001:db8:1::2/32 scope global noprefixroute
          valid_lft forever preferred_lft forever
       inet6 fe80::73d9:6f51:ea6f:863e/64 scope link noprefixroute
          valid_lft forever preferred_lft forever