[Dnsmasq-discuss] DHCPv6 - Relay-reply dhcpv6.option.type 79 Client Link-Layer Address with zero length

[Harald Jensas]

Hi,

The router is dropping relay replies from dnsmasq because it sees the 
Option 79 with lenght of 0 as invalie, i.e less that minimum length.

I have attached a pcap file showing that the reply from dnsmasq does 
include Option 79 with len == 0.

RFC6939 - 6.  DHCPv6 Server Behavior

"""
There is no requirement that a server return this option and its data
in a downstream DHCP message.
"""

I think we want to either copy all of the option data from the 
Relay-forward message, or simply drop the entire option in the reply?


--
Harald Jensås
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