Re: dnscache and oversized answers

(* Reply-to munged *)

John Levine wrote:

>> -    if (r + 1 > sizeof udpbuf) return 0;
>> +    if (r + 1 > sizeof udpbuf) return firsttcp(d);
>>
>>     if (irrelevant(d,udpbuf,r)) return 0;
>>     if (serverwantstcp(udpbuf,r)) return firsttcp(d);

> Thanks, that works great.
> 
> From a security point of view, it'd probably be better to check the
> irrelevant bit before falling back to TCP, but that seems like a minor
> bug since at worst it'd provoke redundant lookups to the real server.

Don't you need the whole packet (which has just been truncated) to call
irrelevant()?


-- 
Regards,
  Daryl Tester

"I'm beginning to wonder about Cap'n Snooze's military credentials."