[Dnsmasq-discuss] using gPXE in chainloader mode

[Simon Kelley]

rance at frontiernet.net wrote:
> Ive puged all the history in the interest of brevity:
> 
> This should be my final post on using gPXE with dnsmasq
> 
> First, the gPXE peop[e claim that there is a bug in dnsmasq that appends 
> an extra chaaracter hex(00) at the end of all dhcp supplied option values.
> 
> a snooped dhcpoffer packet with wireshark confirms the asserstion by the 
> gPXE people.
> 
> The fact is that a 13 character bootfile name is a legth 14 option in 
> the dhcpoffer packet
> 
> I'm not sure if its a bug in dnsmasq or not, as I don't know the RFCs 
> well enough to make a judgement.  But the gPXE people seemed convinced 
> that dnsmasq was somehow "wrong" in this.
> 

I'm a bit short of time to do a complete analysis at the moment, I'll 
get back to you later with that. It worth knowing that dnsmasq is 
supposed to detect buggy microsoft zero-terminated options, and only 
send back zero-terminated options only when it sees them.

ie if the hostname sent by the client is zero-terminated, then all 
string options returned by dnsmasq will also be zero terminated, 
otherwise they won't be. RFC-compliance is definately NOT 
zero-terminated, but that will break eg the Windows 98 DHCP client.

It's possible that this code is being confused, or is too simple-minded,

I'm off to stick pins in my effigy of Bill Gates now......


Cheers,

Simon.