Eu limpei meu iptable e adicionei novas regras. O OSSIM tinha seus próprios iptables e eu uso o webmin.
'iptables -A INPUT -s 0/0 -i eth0 -d 192.168.10.1 -p TCP -j ACCEPT
iptables -A POSTROUTING -t nat -o eth1 -s 192.168.10.0 -d 0/0 -j MASQUERADE
iptables -A FORWARD -t filter -o eth1 -m state --state NEW,ESTABLISHED,RELATED -j ACCEPT
iptables -A FORWARD -t filter -i eth1 -m state --state NEW,ESTABLISHED,RELATED -j ACCEPT '
E deu certo.