options edns0

[Dustin Marquess <dmarquess%gmail.com@localhost>]

Sorry if that has already been fixed, as my -current build is from
about 5 months ago.

Since I use unbound as my local recursive resolver I decided to add
'options edns0' to /etc/resolv.conf.  I noticed as soon as I did that,
DNS resolution broke immediately.  dig is using EDNS0 successfully
however, so I changed it to 'options edns0 debug' and tried again.

I then noticed that the query was sending:

EDNS: version: 0, udp=0, flags=0000

So a 0-sized buffer.  It seems that bind9 allows that and ignores it,
however unbound rejects it.  dig is sending a 4096-byte buffer, and
that works.

Some digging shows that Solaris had a similar problem back in 2007:

http://marc.info/?l=opensolaris-bugs&m=119436900815147&w=2

Looks like NetBSD might still have that issue?  Has anybody gotten
edns0 to work correctly?

-Dustin