Comparing attributes containing MAC addresses

[Alan DeKok]

On Apr 20, 2022, at 8:46 AM, Paul Moser via Freeradius-Users <freeradius-users at lists.freeradius.org> wrote:
> 
> Is there a simple built in way to compare attributes that are MAC addresses for equivalence?
> 
> I need to be able to compare 2 attributes in a packet to see if they are the same, unfortunately the network kit vendor does not format MAC addresses consistently across all attributes (eg User-Name = aa.bb.cc.dd.ee.ff whilst  Calling-Station-Id = aabb:ccdd:eeff)  so a simple string comparison does not work.

  You'll need to write regular expressions and rules to match each format, and normalize them.  Place the normalized MAC addresses into a new attribute, and then compare that.

  e.g. edit raddb/dictionary, and add:

ATTRIBUTE MAC-Address 3000 string

  then in authorize, write a regex.  See policy.d/canonicalization for examples

	if (Calling-Station-Id =~/regex1/) {
		update request {
			MAC-Address := "%{toupper:%{1}-%{2}-%{3}-%{4}-%{5}-%{6}}"
		}
	}
	elsif (Calling-Station-Id =~/regex2/) {
		update request {
			MAC-Address := "%{toupper:..."
		}
	}

  Unfortunately while the RFCs have a recommended string format for MAC addresses, many vendors don't bother following (or even reading) the standards.

  Alan DeKok.