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R__Clark_149098's avatar
R__Clark_149098
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Jan 23, 2019

LDAP Query for Attribute

I apologize if this has been covered in a different article, but I have not been able to find anything that I've had success with. In my environment, a user's DistinguishedName is totally unique, ...
  • R__Clark_149098's avatar
    Feb 05, 2019

    I ultimately got this working by creating an LDAP Query action, I used the following as a SearchFilter:

    (SamAccountName=%{session.logon.last.username})
    

    I set DistinguishedName as a required attribute so that I was able to use it later. These are case sensitive when you try to use them in Variable Assigns, so make sure to check the session variables after a login attempt if things aren't working.

    The format of my LDAP users DN is CN=Bob\, Smith... or CN=Bob... so I had to cover both cases. The F5 adds an extra slash to the session variable to make it a literal slash in TCL (my guess). I had to create a variable assign to remove that extra slash so when it's sent to the LDAP server it understands it.

    This was the expression field of my variable assign:

    set dn "[mcget {session.ldap.last.attr.dn}]"
    if {[string first "\\" $dn] != -1} {
        return [string map {\\\\ \\} $dn]
    } else {
        return $dn
    }
    

    Finally I created an LDAP auth action with the following in the UserDN. SearchDN and SearchFilter are empty.

    I had to open a case with F5 to figure out how to not send hex to my LDAP server. They key is the :noconv function.

    %{dn:noconv}

    After this authentication worked!!