Trying to set up a block for Yahoo messenger, this app connects on various open ports, including 80, so the best way I can figure is to block the IP ranges used by Yahoo servers. Some research found a number of servers used for chat, including login.yahoo.com (69.147.112.160), but I can't seem to find the right way to filter these in iptables.
Here's a clip of my firewall.user file (White Russian 0.9) with the relevant commands.
#!/bin/sh
. /etc/functions.sh
WAN=$(nvram get wan_ifname)
LAN=$(nvram get lan_ifname)
iptables -F input_rule
iptables -F output_rule
iptables -F forwarding_rule
iptables -t nat -F prerouting_rule
iptables -t nat -F postrouting_rule
#drop
iptables -t nat -A prerouting_rule -s 66.163.0.0/16 -j DROP
iptables -t nat -A prerouting_rule -s 67.195.186.0/24 -j DROP
iptables -t nat -A prerouting_rule -s 68.142.230.0/24 -j DROP
iptables -t nat -A prerouting_rule -s 69.147.112.0/24 -j DROP
iptables -t nat -A prerouting_rule -s 98.136.112.0/24 -j DROP
iptables -t nat -A prerouting_rule -s 208.69.32.0/24 -j DROP
iptables -t nat -A prerouting_rule -s 216.136.0.0/16 -j DROPI've also tried the above on the input_rule and output_rule, no success, after committing changes, I can still use a web browser and reach login.yahoo.com.