Re: [Full-disclosure] Gmail and China's GFW




On Mar 21, 2011, at 4:53 PM, nix@xxxxxxxxxxxxxxxx wrote:

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!


Thanks for the information. I was not actually aware of that you can block
with iptables using hex strings. Very nice.


Forgot to say, in terms of performance. It's better to use -j REJECT
instead of DROP (then no timeout is caused and the connection is rejected
with ICMP destination unreachable.


Not if you want it to look like a problem with Google's infrastructure rather than an active block where initiator can see the source of the ICMP datagrams.

--
chort

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