[EXT] Fetching memberOf attribute

[Matvey Teplov]

Hi Brian,

How do you define ldap_ad-LDAP-Group?

Best regards Matvey Teplov
+31 62 705 12 73
________________________________
From: Brian Julin <BJulin at clarku.edu>
Sent: 15 May 2025 15:02
To: freeradius-users at lists.freeradius.org <freeradius-users at lists.freeradius.org>
Cc: Matvey Teplov <matvey.teplov at nomios.nl>
Subject: Re: [EXT] Fetching memberOf attribute

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Matvey Teplov via Freeradius-Users <freeradius-users at lists.freeradius.org> wrote:

> Hi Guys,

> I cannot get the ldap module to fetch a memberOf attribute from AD - it is not putting it
> as a filter parameter in the LDAP search packet. I need this list later to search through for
> port-authentication phase through the groups in session-state:LDAP-Group[*]'s to identify
> which ones are present and return a proper VSA. The LDAP configuration is as follows:

We use this, because it searches the group membership hierarchy so nested groups work:

    user {
     ...
      filter = "(&(objectClass=user)(sAMAccountName=%{Stripped-User-Name}))"
      scope = 'sub'
    }
    group {
     ...
      scope = 'sub'
      filter = '(objectCategory=group)'
      membership_filter = "(member:1.2.840.113556.1.4.1941:=%{&control:Ldap-UserDN})"
     ...
   }

You can thank Microsoft for the ugly OID, as far as I know it has no textual alias.

then:

if (&ldap_ad-LDAP-Group[*] ==  "whatever")

...that statement will be true if any one of the users groups, including groups inherited from other groups, is "whatever", no need for a for loop unless you need to do something fancy.

Do note that if you have a lot of groups in the OU the search will not be especially efficient, it will even rummage through your printers and whatnot.  We made a new OU for the top level RADIUS groups and then could put groups from our other OUs inside those groups to reduce the scope of the search to just users.