In this chapter, we earlier identified what port had a rule on it for the router; this is a technique you want to continue to practice with on your ranges, but we have not looked specifically at the firewall itself. We need to see what the firewall allows and blocks if we want to be able to get through it successfully. As has been mentioned before, this can be a significant challenge, and more often than not, we are limited to using the ports that are open to get through the firewall.

We mentioned that a router is a form of a stateless firewall, and we showed that an Nmap scan of the router that has an ACL applied on it will show the ports that have a rule set. We not only discussed it, but we went on and proved it. We will take this one step further, first with our router, and then with our iptables and Smoothwall firewall.

We want to look at what traffic is allowed to pass through the stateless firewall. Since we have already done this with the scan earlier...