VSA encoding

[Alan DeKok]

Geoffroy Arnoud <geoffroy.arnoud at free.fr> wrote:
> I saw a strange dictionary amongst FreeRADIUS dictionaries: for USR robotics
> dictionay.usr
> It is talking about a NMC encoding, and the follinwg is added after the vendor
> id declaration:
> "format=4,0"
> As anyone explanation about this type of encoding?

  It's USR's old format.  4 bytes of attribute type, and no length.
The VSA length is used for the length instead.

> From my side, I have a vendor (having a vendor-id) that uses the following
> encoding:
> RADIUS Attribute Id (1 byte) = 26
> RADIUS Attribute Length (1 byte) = total length of attribute value + 2
> Vendor ID (4 bytes)
> A Project Type attribute (1 byte)
> And as much attributes as possible (up to 248 bytes), using TLV where T is 1
> byte and L is 1 byte.

  Ugh.  What the heck is the "project type"?

> Is FreeRADIUS able to support such encoding method?
> Or maybe with only one TLV attribute per RADIUS attribute (26 + L +
> VendorID + ProjectType + TLV)?

  For now, only with the Vendor-Specific = 0x... method.

  If the server does support this, what does it do with the project
type?  It doesn't fit into the normal "Attribute = value" system used
by the server.

  Are there documents from the vendor describing hw they think it
should be used?  And who the heck comes up with these things?

  Alan DeKok.