RADIUS

Version 3.2

Overview

With the RADIUS app, network access (for example to the WiFi network) can be controlled on a per-user basis, using the RADIUS protocol.

Installation

RADIUS is available through the App Center and can be installed using the corresponding UMC App Center module. It can be installed on multiple machines; Installing it runs a freeradius server on that machine that clients (e.g. access points) can contact via RADIUS to check network access requests.

The RADIUS app can also be installed on UCS@school systems. In this case, the network access can be given to users or groups regardless of the Internet rule or computer room settings.

Configuration

Allowed users

By default users are denied access to the network. Enabling the checkbox for network access on the RADIUS tab, gives a user access. The checkbox can also be set on groups, which allows all users in this group access.

Group Access Example

MAC filtering

By default access to the network is allowed for every device (assuming the used user name has access). It can be restricted to only allow specific devices. It can be enabled by setting the UCR variable radius/mac/whitelisting to true. When enabled, the device used to access the network is looked up via the LDAP attribute "macAddress" and the resulting computer object must have network access granted (either directly or via one of its groups) too.

Access Points

All access points must be registered in the configuration file /etc/freeradius/clients.conf. For each access point a random password should be created. (For example using the command makepasswd). The shortname can be chosen at will. Example entry for an access point:

client 192.168.100.101 {
    secret = a9RPAeVG
    shortname = AP01
}

The access points must then be configured to use 802.1x ("WPA Enterprise") authentication; The address of the server where the RADIUS app is installed should be set as "RADIUS server" and the password must be set to the "secret" from the clients.conf entry for that access point.

Clients

WiFi-clients have to be configured to use WPA with PEAP and MSCHAPv2 for authentication.

See for example the configuration for Windows or the configuration for Android.

Debugging

The tool univention-radius-check-access can be used to evaluate the current access policy for a given user and/or station ID (MAC address). It can be executed as root on the server where univention-radius is installed:

root@master211:~# univention-radius-check-access --username=stefan
DENY 'uid=stefan,cn=users,dc=ucs,dc=local'
'uid=stefan,cn=users,dc=ucs,dc=local'
-> DENY 'cn=Domain Users,cn=groups,dc=ucs,dc=local'
-> 'cn=Domain Users,cn=groups,dc=ucs,dc=local'
-> -> DENY 'cn=Users,cn=Builtin,dc=ucs,dc=local'
-> -> 'cn=Users,cn=Builtin,dc=ucs,dc=local'
Thus access is DENIED.

root@master211:~# univention-radius-check-access --username=janek
DENY 'uid=janek,cn=users,dc=ucs,dc=local'
'uid=janek,cn=users,dc=ucs,dc=local'
-> DENY 'cn=Domain Users,cn=groups,dc=ucs,dc=local'
-> ALLOW 'cn=Network Access,cn=groups,dc=ucs,dc=local'
-> 'cn=Domain Users,cn=groups,dc=ucs,dc=local'
-> -> DENY 'cn=Users,cn=Builtin,dc=ucs,dc=local'
-> -> 'cn=Users,cn=Builtin,dc=ucs,dc=local'
-> 'cn=Network Access,cn=groups,dc=ucs,dc=local'
Thus access is ALLOWED.
root@master211:~#

It prints a detailed explanation and sets the exit code depending on the access (0 for granted access, 1 for denied access)

Links

• freeradius.org Homepage of the freeRADIUS project