opened proxies

[rtyug]

how is it possible to forbid fully access to to  proxies are opened which appear every day in great numbers??

does can it is possible a script to do something?
1) can it is possible to define proxies on ip who called and port
2) to make attempt be connected to it proxies
3) if to be connected that to cut
down or not?

[青山 素子]

Having a little trouble understanding, but it seems you want to block people using proxies?

There are two types of proxies, ones that pass information and ones that do not. It can be difficult to detect the ones that don't advertise they are proxies. You can try to find some public lists, but those are usually outdated and mostly incorrect.

If you just want to block the proxies that advertise themselves, deny any connection where there is an X-Forwarded-For header.

Please note that this will affect valid users, as many companies and some ISPs force their users behind proxies. Anyone in that situation would not be able to get in either.

[rtyug]

I wanted to do a script which will determine:

1)  to determine proxies server
2)  to determine his port
3) to look in a "white list", if there is this ip present, to make off an operation...
4) connecting to it proxies to the server
5) if connecting was completed successfully
6) to write down in a "black-list"

very much a spam is used by these proxies...


ipfw in table

[青山 素子]

The problem is that a proxy can operate on pretty much any port, and don't have to advertise their function. While you can do some checks on popular ports, it won't catch all that many spammers, and will hurt possibly legitimate users.

Most spamming activity operates directly from compromised home computers nowadays.

[rtyug]

http://www.0x000000.com/TorSniff.phps
http://support.routeme.de/qsheff/qsheff.msg