[Devel] asynchronous DNS

[Klaus Darilion]

Olle E Johansson wrote:
> 
> 12 okt 2006 kl. 11.30 skrev Klaus Darilion:
> 
>> Hi!
>>
>> Are there any plans for including an asynchronous DNS resolver into 
>> openser? It still bothers me that openser is vulnerable to DNS based 
>> DoS attackes (lame delegations (SERVFAIL )are not cached in the 
>> resolving DNS server).
> 
> We have the same problem in Asterisk and needs to do something. I've 
> looked at the ARES or C-ARES libraries. These
> are the libraries also used by reciprocate.

I'm currently going to the bind sources. There is a feature "lame-ttl" 
to cache lame name servers. Although I created several lame delegations 
bind never caches them :-(

My idea is to solve this at the recursive name server - then it works 
with Asterisk too :-)

regards
klaus