iptables to redirect traffic through AP router?

["Nguyễn Hồng Quân" <quannguyen@mbm.vn>]

Hello

I run a wifi router in AP mode and want to setup iptables rule to redirect
traffics to Google AdSense to a proxy. I added this chain and rule to
NAT table:
1. Create GoogleAds chain
-N GoogleAds
2. Append this chain to PREROUTING chain
-A PREROUTING -j GoogleAds
3. In GoogleAds chain, I make some rules:
-A GoogleAds -d 74.125.235.25/32 -p tcp -m tcp --dport 80 -j REDIRECT
--to-ports 8888
-A GoogleAds -d 74.125.235.26/32 -p tcp -m tcp --dport 80 -j REDIRECT
--to-ports 8888
-A GoogleAds -d 74.125.235.13/32 -p tcp -m tcp --dport 80 -j REDIRECT
--to-ports 8888

But the problem is that no traffic is driven to those rules, though it
is driven to GoogleAds chain
Screenshot: http://i.imgur.com/bpRBE.png

I suspect this is related to AP mode of router. I tried on OpenWrt on
VirtualBox and successful.

How should right iptables rule is?

(I brought the GoogleAds chain to POSTROUTING, but got error ip_tables:
REDIRECT target: bad hook_mask 0x10/0x9)

Thanks.

-- 
Regards,
Qu√¢n

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