On Wed, 1 Apr 2009, Hugo Miguel Mendes wrote: > I'm using iptables 1.3.8, and I need to implement a full cone NAT which had to be capable of doing the following: > 1. A packet is sent from a machine in the LAN from Address1:port100 to a machine in the WAN with Address3:port200, the NAT converts the local Address1:port100 to Address2:port100 which is the address assigned to the home router by the ISP. So this packet is sent with source: Address2:port100 and destination: Address3:port200. > 2. The packet received by the machine in the WAN in 1) is processed and then the answer comes from a different machine with a different address but using the same ports. So the response packet is sent by Address4:port200 to Address2:port100. So this packet has source: Address4:port200 and destination: Address2:port100. > 3. When the home router receives the response packet it has to ignore the sending address in the matching table, so that all traffic received in Address2:port100 is simply forward to Address1:port100. This is just a Full Cone NAT. > > I have read some tutorials about iptables and the only way I have found to do this is make rule that forwards all traffic that arrives in Address2:port100 to Address1:port100. This does the work for just one machine on the LAN which has a static ip and will always contact the same machine on the WAN. > What I really want to do is implement a Full Cone NAT in which a packet sent from Address1:port100 which is translated to Address2:port100 by the NAT and goes to Address3:port200, activates port100 in the home router so that any packets arriving in port100 will be forwarded to Address1:por100. And this would just work for any number of machines. > > Is there anyway of doing so in the actual iptables or I will have to add this feature to iptables? Netfilter implements port restricted cone NAT, so you cannot create a full cone NAT with it. I don't think it'd be easy to add such a feature. Best regards, Jozsef - E-mail : kadlec@xxxxxxxxxxxxxxxxx, kadlec@xxxxxxxxxxxx PGP key : http://www.kfki.hu/~kadlec/pgp_public_key.txt Address : KFKI Research Institute for Particle and Nuclear Physics H-1525 Budapest 114, POB. 49, Hungary -- To unsubscribe from this list: send the line "unsubscribe netfilter" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html