To get to the point i have a workgroup A and workgroup B both on winXP Home, i have enabled file sharing but Home has only simple file sharing so users from workgroup A can see shares in workgroup B, since i have 2 Switches for 2 workgroups that are connected i want to put something simple in between, like a firewall, but just to block ports for windows file sharing and retain LAN connectivity, network neighborhood, LAN Games etc...
I tried Clarckconnect firewall and ipcop but no luck, maybe just didn't configured it right, don't know... I someone has any idea... Thanks...

Help much appreciated...

Hi,

what do you mean by network neighborhood, isn't it file sharing ?

anyway, windows file sharing uses ports 137, 13_ and 139, so this simple iptables lines would work pretty well :
iptables -A FORWARD -p tcp --sport 137:139 -j DROP
iptables -A FORWARD -p tcp --dport 137:139 -j DROP
iptables -A FORWARD -p udp --sport 137:139 -j DROP
iptables -A FORWARD -p udp --sport 137:139 -j DROP
echo 1 > /proc/sys/net/ipv4/ip_forward (enables forwarding between NICs)

If you want your 2 LANs in the same subnet, then configure a bridge : just look for brctl on Internet

Hi,

Thanks very much for the info, it did help, bridging is the way to go for me, just blocking two ports is required 139 and 445 for the xp...

Thanks Again....