Description
The article describes how to restrict SSL VPN connectivity from certain countries. By default, the SSL VPN is accessible to all public IP addresses from the Internet, but it is possible to restrict the access to a specified set of allowed IP addresses using IP/Subnet Address Objects as well as Geo-IP Address objects.
Note:
The Restrict Access (aka source-address) configuration can be modified without disrupting existing SSL VPN connections, though only if the modifications continue to allow a given user's source address to connect. For example:
- If the Restrict Access option is set to Limit access to specific hosts, and the Hosts include Canada and USA Geography Address objects, then users in Canada and the USA will be able to connect to the SSL VPN.
- If Canada is then removed from this config and the changes are applied, any connected Canadian Users will be disconnected (since they have become disallowed).
- On the other hand, adding a Mexico Geography Address object to the allowed hosts will not disrupt any existing connections for USA/Canadian VPN users.
Scope
FortiGate.
Solution
From CLI.
- Configure the firewall address with the geography type.
config firewall address
edit "restriction_poland"
set type geography
set country "PL" <- Only allows connections from Poland.
next
end
- Configure the firewall address group.
config firewall addrgrp
edit "Geo_restriction_ssl_vpn"
set member "restriction_poland"
next
end
- Configure the firewall address group as the source-address under SSL VPN settings.
config vpn ssl settings
set servercert "Fortinet_Factory"
set tunnel-ip-pools "SSLVPN_TUNNEL_ADDR1"
set tunnel-ipv6-pools "SSLVPN_TUNNEL_IPv6_ADDR1"
set port 444
set source-interface "wan1"
set source-address "Geo_restriction_ssl_vpn"
end
From the GUI.
- Go to Policy & Objects -> Addresses, select 'Create new', select 'Geography' as the address Type, and select the country to allow.
If there is more than one country to allow, make a group on the firewall. Refer to this KB article Technical Tip: Script to create Address objects and one address group for all geography countries on... to import all geography address objects via script.
- After creating the country on the addresses, the same must be mapped on the firewall SSL VPN settings to restrict access. Go to VPN -> SSL-VPN Settings. Under 'Restrict Access', select 'Limit access to specific hosts' and add the address object created in Step 1 to allow access to the VPN.
This will ensure that only the selected Country/Region IP addresses will be able to connect to the SSL VPN. Only IP and Geo objects are allowed to be configured here. User and User Group objects CANNOT be configured here.
Note:
- If the original public source IP is not visible to the FortiGate then the geo-ip location-based restriction will not work. For example, if there is an uplink device that is doing a source NAT on the SSL VPN incoming connections then the geo-ip-based restriction will not work and the access to the SSL VPN gets blocked.
- If there are SSL VPN authentication rules that have source-address defined as 'all', the globally configured source-address will not work. Make sure to remove source-address from the authentication rules, or configure appropriate source-addresses from allowed countries for each authentication rule.
Furthermore, it is possible to include a public IP address or range of IP addresses to allow access to IP addresses that are not included or categorized in the selected geographical area.
In the preceding example, users from Poland are permitted to connect to this SSL VPN. However, if it is also necessary to add a few individual IP addresses/ranges from an undefined Country/Region, the address objects can be included under SSL VPN settings as shown below.
If there are still hits from different IPs from different countries that are not allowed, refer to the information and steps below:
- It is possible to see other IPs trying to log into the VPN event logs (other than the US that is allowed).
- It is possible to check the location through the geo IP command. Be sure to update the geo IP database on FortiGate first with the following command:
execute update-geo-ip
To find the location of the IP:
diagnose firewall ipgeo ip2country x.x.x.x <- The IP.
Alternatively, check with Instant IP Address Lookup (whatismyipaddress.com).
- It is possible to create an authentication rule if one is not present. If one is present, add the source interface and source address under it:
config vpn ssl settings
config authentication-rule
edit 1
set source-interface "wan1" <----- Interface specified in SSL VPN.
set source-address "Allow US IPs Only" <----- Just use the country desired to allow.
set groups "SSLVPN_users" <----- This is the group in the policy of SSL VPN.
set portal "full-access"
- After these changes, it will not be possible to see any other attempt from outside the US in the VPN events logs. Another method would be to use local-in-policy to block any attempts to connect to SSL VPN.
Create a policy that allows traffic from a specific country:
config firewall local-in-policy
edit 0
set intf "wan1"
set srcaddr "Allow US IPs Only"
set dstaddr "all"
set service "SSLVPN-Port" <- Port that is used for SSL VPN connections.
set schedule "always"
set action accept
next
end
Second deny access from all other countries:
config firewall local-in-policy
edit 1
set intf "wan1"
set srcaddr all
set dstaddr "all"
set service "SSLVPN-Port" <-- Port that is used for SSL VPN connections.
set schedule "always"
set action deny
next
end
After this, it will show newly created policies via GUI.
Note that it can be necessary to activate local-in-policy in GUI to view the current settings under System -> Feature Visibility -> Check Local-In-Policy and select Apply.
Note:
Starting from FortiGate v7.6.0, the Local-in-Policy can now be also configured in the GUI. Refer to this document for reference: Technical Tip: Creating a Local-In policy (IPv4 and IPv6) on GUI.
For SSL VPN, VPN configuration, and port used in this article, more information is available via this link: SSL VPN best practices | FortiGate / FortiOS 7.4.1 | Fortinet Document Library
