<item> <descr> Source routing is another way for an attacker to try to reach non-routable addresses behind your box. It can also be used to probe for information about your internal networks. These functions come enabled as part of the standard FreeBSD core system. </descr> <tunable>net.inet.ip.sourceroute</tunable> <value>default</value>... <tunable>net.inet.ip.accept_sourceroute</tunable> <value>default</value> </item>