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A common question regarding this definition is: "why is TLS also configured? I don't want it, can I disable it?" The answer is: the TTLS and PEAP sections depend on the tls stanza for the definition of which server certificates to use. You cannot delete the stanza, but that doesn't mean you can't effectively disable TLS: the tls stanza contains the ca_file parameter. Only clients with a TLS client certificate from this CA will be accepted. We have just created a brand-new CA with the "bootstrap" script. Simply don't issue nor distribute any client certificates from this CA, then nobody will be able to log in with EAP-TLS.

Another question is regarding the mschapv2 section. For all practical purposes, the easy answer is that it is a piece of magic and needs to be there for PEAP to work. If you are curious regarding the gory details, please let us know.

Note that one parameter for both the ttls and peap stanza is "virtual_server = eduroam-inner-tunnel". This means that the inner EAP authentication will be carried out in this other virtual server, which we will define later.

Virtual server eduroam: enable EAP, make Operator-Name conditional

Compared to the eduroam SP config, you need to additionally mention the "eap" module in both the authorize and authenticate stanza of the file /etc/raddb/sites-enabled/eduroam so that your server can process EAP requests from your own userbase.

You should also make sure to only tag those incoming requests with the Operator-Name attribute which actually originate from your own WiFi gear - as an IdP, your own users roaming elsewhere will also be processed, but they should not carry your own Operator-Name. For the purposes of this wiki, let's assume that you are connected to one FLR server, and it is defined in your clients.conf with the shortname "antarctica-flr-1" (see below for the exact definition).

It will then look like the following: 

...

Note that in newer versions of FreeRADIUS (>3.0.14) there is a new tls-config section that allows you to configure the common TLS configuration without configuring the TLS EAP type. The config above is backwards compatable, but if you want to take advantage of the new section you can replace the name of the "tls" block above with "tls-config tls-common" and then reference it from each EAP type with "tls = tls-common" (the example eap config shows you how to do this).

Another question is regarding the mschapv2 section. For all practical purposes, the easy answer is that it is a piece of magic and needs to be there for PEAP to work. If you are curious regarding the gory details, please let us know.

Note that one parameter for both the ttls and peap stanza is "virtual_server = eduroam-inner-tunnel". This means that the inner EAP authentication will be carried out in this other virtual server, which we will define later.

Virtual server eduroam: enable EAP, make Operator-Name conditional

Compared to the eduroam SP config, you need to additionally mention the "eap" module in both the authorize and authenticate stanza of the file /etc/raddb/sites-enabled/eduroam so that your server can process EAP requests from your own userbase.

You should also make sure to only tag those incoming requests with the Operator-Name attribute which actually originate from your own WiFi gear - as an IdP, your own users roaming elsewhere will also be processed, but they should not carry your own Operator-Name. For the purposes of this wiki, let's assume that you are connected to one FLR server, and it is defined in your clients.conf with the shortname "antarctica-flr-1" (see below for the exact definition).

It will then look like the following: 

Code Block
authorize {
                if ("%{client:shortname}" != "antarctica-flr-1") {
                   update request {
                           Operator-Name := "1yourdomain.tld"
                            # the literal number "1" above is an important prefix! Do not change it!
                   }
                }
                auth_log
                suffix
                eap
        }

authenticate {
       eap
}

...

If the IdP and SP are colocated, it is possible to *locally* also accept users who erronuously omitted their realm (just "user123"). This requires further configuration, but it is strongly discouraged, because it will is NOT permitted by the eduroam policy (read 6.3.2 bullet 6 under AAA Servers of the current service definition document: "The outer EAP identities (and with it, RADIUS User-Name attributes) for the IdP MUST be in the format of arbitrary@realm"). Allowing this also requires further configuration and it is strongly discouraged, because it will give such users a "halfways-working" experience: they will be able to use eduroam when on their own IdP's campus, because no routing information needs to be evaluated, but their account will fail at all other locations. Therefore, this guide does not include instructions for that kind of setup.

Processing incoming requests

As an eduroam IdP, your users can go to other eduroam hotspots around the globe. They will still be authenticated at your server. In these roaming cases, your upstream FLR servers will send Access-Requests to your server. Surprisingly, it is very simple to configure that: these upstream servers are simply clients - just like an Access Point. So, simply add client stanzas for your FLR servers into clients.conf:

...

that kind of setup.

Processing incoming requests

As an eduroam IdP, your users can go to other eduroam hotspots around the globe. They will still be authenticated at your server. In these roaming cases, your upstream FLR servers will send Access-Requests to your server. Surprisingly, it is very simple to configure that: these upstream servers are simply clients - just like an Access Point. So, simply add client stanzas for your FLR servers into clients.conf:

Code Block
 client antarctica-flr-1 {
        ipaddr                          = 172.20.1.2
        netmask                         = 32
        secret                          = secretstuff
        require_message_authenticator   = yes
        shortname                       = antarctica-flr-1
        nastype                         = other
        virtual_server                  = eduroam
}
CUI for eduroam IdP

To use the Chargeable-User-Identity (CUI) you must already use the Operator-Name attribute. This documentation is only for FreeRADIUS 3.0.X release.

Modify the log module

Edit "eduroam_cui_log" file in the mods-available/ subdirectory and add the following lines to your virtual inner server :

Code Block
...
linelog cui_inner_log {
#    filename = syslog
    filename = ${logdir}/radius.log
    format = ""
    reference = "inner_auth_log.%{%{reply:Packet-Type}:-format}"
    inner_auth_log {
        Access-Accept = "%t : eduroam-inner-auth#VISINST=%{request:Operator-Name}#USER=%{User-Name}#CSI=%{%{Calling-Station-Id}:-Unknown Caller Id}#NAS=%{%{Called-Station-Id}:-Unknown Access Point}#CUI=%{%{%{reply:Chargeable-User-Identity}:-%{outer.reply:Chargeable-User-Identity}}:-Local User}#RESULT=OK#"
        Access-Reject = "%t : eduroam-inner-auth#VISINST=%{request:Operator-Name}#USER=%{User-Name}#CSI=%{%{Calling-Station-Id}:-Unknown Caller Id}#NAS=%{%{Called-Station-Id}:-Unknown Access Point}#CUI=%{%{%{reply:Chargeable-User-Identity}:-%{outer.reply:Chargeable-User-Identity}}:-Local User}#RESULT=FAIL#"
    }
}


Use policy and module in your eduroam-inner-tunnel virtual server

Add 'cui-inner' (policy already defined, you don't need to change it) and 'cui_inner_log' in post-auth section :

Code Block
server eduroam-inner-tunnel {
...
		post-auth {
				reply_log
				cui_inner_log
				cui-inner
				Post-Auth-Type REJECT {
					reply_log
					cui_inner_log
				}
		}
...
}


That's it! Now your server is prepared for eduroam IdP operation! You can add users to your "database" by amending the "users" file; if you do, you will unfortunately have to restart FreeRADIUS so that it picks up the change.

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