Re: Gmail and China's GFW

[bk <chort0 () gmail com>]

On Mar 21, 2011, at 10:52 AM, Alien Chatter wrote:

> $ sudo iptables -I INPUT -m string --algo bm --hex-string
> '|476f6f676c6520496e63311830160603550403140f6d61696c2e676f6f676c652e636f6d30819f30|'
> -j DROP
>
> Try it, you will get a connection timeout:
>
> $ curl --connect-timeout 60 https://mail.google.com/
> curl: (28) SSL connection timeout
>
> The same applies for Twitter, Facebook... Much more efficient than
> DNS/IP blocking!

Because searching for a bytestring in payload generates so much less load than just overriding a DNS result at the 
recursive server (that users are forced to issue queries to) or a simply drop SYNs based on IP header value that 
routers/firewalls are optimized for...

I think you forgot your coffee this morning.  It's not just for aliens you know.

--
chort

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