On Sep 5, 2025, at 4:31 AM, Ľudovít Mikula <ludovit.mikula@mikori.sk> wrote:
is it possible to automatically decode Vendor Specific Information from inocoming DHCP packet in freeradius 3.2.28?
The DHCP xlat just uses the normal DHCP decoder, but there are limitations.
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)
The issue is that in v3, DHCP is already a "vendor" dictionary. So it can't do vendor inside of vendor.
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 ?
Not in v3. And, of course, v4 supports this. We're using it in production with DHCP vendor options. Alan DeKok.