#-------------------------------------------------------------------------- # ed1 - external interface # fxp0 - internal interface #-------------------------------------------------------------------------- # First, nasty packets which we don't want near us at all # packets which are too short to be real except echo replies on lo0 pass in log quick on lo0 proto icmp from 127.0.0.1/8 to 127.0.0.1/8 with short block in log quick all with short block in log quick all with opt lsrr block in log quick all with opt ssrr #-------------------------------------------------------------------------- # loopback packets left unmolested pass in log quick on lo0 all pass out log quick on lo0 all #-------------------------------------------------------------------------- # Group setup: # 100 incoming ed1 # 150 outgoing ed1 # 200 incoming fxp0 # 250 outgoing fxp0 #-------------------------------------------------------------------------- block in log body on ed1 all head 100 block out log body on ed1 all head 150 #-------------------------------------------------------------------------- block in log on fxp0 all head 200 block out log on fxp0 all head 250 #-------------------------------------------------------------------------- # incoming ed1 traffic - group 100 # 1) prevent localhost spoofing block in log quick from 127.0.0.1/32 to 192.168.0.0/24 group 100 block in log quick from 127.0.0.1/32 to 192.168.1.0/24 group 100 block in log quick from any to 127.0.0.1/8 group 100 #-------------------------------------------------------------------------- # 2) deny pakets which should not be seen on th internet (paranoid) block in log quick from 10.0.0.0/8 to any group 100 block in log quick from any to 10.0.0.0/8 group 100 block in log quick from 172.16.0.0/16 to any group 100 block in log quick from any to 172.16.0.0/16 group 100 block in log quick from 192.168.0.0/16 to any group 100 block in log from any to 192.168.0.0/16 group 100 # 3) implement policy # allow incoming ftp-data pass in log quick proto tcp/udp from any to 192.168.1.1/24 keep state group 100 # if nothing applies, block and return icmp-replies (unreachable and rst) block return-icmp(net-unr) in proto udp from any to any group 100 block return-rst in log proto tcp from any to any group 100 #-------------------------------------------------------------------------- # outgoing ed1 traffic - group 150 # Setup outgoing DNS pass out log quick proto tcp/udp from any to 212.40.0.10 port = 53 keep state group 150 pass out log quick proto tcp/udp from any to 212.40.5.50 port = 53 keep state group 150 # allow outgoing http-service pass out log quick proto tcp from any to any port = 80 flags S/SA keep state keep frags group 150 # allow outgoing smtp traffic pass out log quick proto tcp from 192.168.1.1/24 to any port = 25 flags S/SA keep state group 150 # allow outgoing pop3 traffic pass out log quick proto tcp from 192.168.1.1/24 to any port = 110 flags S/SA keep state group 150 # allow outgoing ftp traffic pass out log quick proto tcp/udp from 192.168.1.1/24 to any port = ftp keep state group 150 pass out log quick proto icmp from any to any keep state keep frags group 150 #-------------------------------------------------------------------------- # incoming traffic on fxp0 - group 200 #-------------------------------------------------------------------------- # 1) prevent localhost spoofing block in log quick from 127.0.0.0/8 to any group 200 block in log quick from 192.168.0.1/32 to any group 200 block in log quick from 192.168.1.110/24 to any group 200 pass in log quick from any to any group 200 #-------------------------------------------------------------------------- # outgoing traffic on fxp0 - group 250 #-------------------------------------------------------------------------- block out log quick from 127.0.0.0/8 to any group 250 block out quick from any to 127.0.0.0/8 group 250 block out log quick from any to 192.168.0.1/32 group 250 pass out log quick from any to nay group 250 #--------------------------------------------------------------------------