From mboxrd@z Thu Jan 1 00:00:00 1970 From: Barry Fawthrop Subject: Re: IP Vs DNS Date: Tue, 11 Oct 2005 20:00:15 -0400 Message-ID: <434C520F.4050308@ttienterprises.org> References: <434C28FB.3000805@ttienterprises.org> <20051011231030.GA18418@salty> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20051011231030.GA18418@salty> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: netfilter-bounces@lists.netfilter.org Errors-To: netfilter-bounces@lists.netfilter.org Content-Type: text/plain; charset="us-ascii"; format="flowed" To: netfilter@lists.netfilter.org Jim Laurino wrote: >> Greetings all >> >> with an IPTABLES ruleset you can specify an IP address to be >> allowed/blocked >> iptables INPUT -s 12.12.12.12 -j ALLOW >> >> But can this be done with a DNS name >> iptables INPUT -s www.name.com -j ALLOW > > > IPTABLES accepts DNS names, but the DNS lookup is performed > when the rule is placed in the kernel, > not when the rule is evaluated against a packet. > The kernel (netfilter) rules use ip address only. > > To achieve what you want, I think you would have to > update the rule whenever the DNS mapping changed. > How can this be done on a per packet basis, where the IP is checked regularly or can the table be flushed and reloaded every hour. What would be the negative of doing a reload each hour?? Thanks in Advance -- No virus found in this outgoing message. Checked by AVG Anti-Virus. Version: 7.0.344 / Virus Database: 267.11.14/129 - Release Date: 10/11/2005