How to extract vendor specific information from Sub-Option 9 of Option 82

5 Sep 2025

      Hi all,

   is it possible to automatically decode Vendor Specific Information 
from inocoming DHCP packet in freeradius 3.2.28?

In DHCP Discover Option 82 -> Sub-Option 9 I am receiving vendor 
specific information and I'd like to have it automatically decoded.

If I got the docs right, I need to create a dictionary and then the 
defined attributes should be accessible by 
%{dhcp_options:<Attribute-ref>}  (after enabling dhcp mod)

I am a bit struggling with writing the dictionary tbh (I've checked also 
the suggested dictionary.alcatel.sr and dictionary.erx).

I am interested in two TLVs:

enterprise number: 0000061b (dec: 1563)

       03:
         length: 0a (dec: 10)
         data: 444d 5a2d 434f 532d 3032  ("DMZ-COS-02")

       01:
         length: 0e (dec: 14)
         data: 4554 492d 5250 442d 504f 5254 2d30 ("ETI-RPD-PORT-0")

I was able to get the information with "unpack" from 
DHCP-Vendor-Specific-Information but am wondering whether this can be 
achieved by defining a custom dictionary and using dhcp_options ?

Regards
-- 
Ľudovít Mikula