Understanding the v6 relay agent workflow

[Petrin, Benjamin]

Ok, hopefully someone will be able to comment a bit further on how things work in v6. What I'm looking to do (eventually) is make some modifications to the relay agent to allow it to dig the hardware address out of the raw packet and tack it on as an option so that the DHCP server can have access to the hardware address of the client requesting an IP (or renewing...etc). This was suggested as a possible solution by Frank Sweetser in the "DHCPv6 host-identifier, the Never Ending Thread" discussing taking place in dhcp-users, if anyone has been following that.

The thing is, I can see the low level functions like "do_packet6" as well as the higher level ones like "dispatch" but I'm unable to follow things down the line. I think I'm simply getting lost in some of the abstraction. Can anyone point out some good starting points for what I should be exploring further to move towards my eventual goal?

Many thanks,
Benjamin Petrin


________________________________________
From: Ted Lemon [Ted.Lemon at nominum.com]
Sent: Monday, March 23, 2009 1:52 PM
To: Petrin, Benjamin
Cc: dhcp-hackers at lists.isc.org
Subject: Re: Understanding the v6 relay agent workflow

The relay agent options thing in the v4 relay agent is a hack that I
put in because I didn't want to fully decode the packet there, and in
particular because relay agent options in v4 are a bit of a hack as
well - they violate the standard way of packing options in a DHCP
packet.   I don't know how it's done in the v6 relay because I didn't
write that code, but hopefully the hack was unnecessary there.