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@@ -1,66 +0,0 @@
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-
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- Part one: Overview and explanation
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-
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-Because tor is an application-level proxy, it needs client-side support
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-from every client program that wants to use it. (This is different from
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-systems like Freedom, which used a single client-side program to capture
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-all packets and redirect them to the Freedom network.) Client applications
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-need two general classes of modifications to be compatible with tor:
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-
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-1) Whenever they call connect(), they instead should connect() to the
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-local onion proxy and tell it "address and port". The onion proxy will
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-itself make a connection to "address and port", and then the client
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-application can talk through that socket as if it's directly connected. To
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-support as many applications as possible, tor uses the common "socks"
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-protocol which does exactly the above. So applications with socks support
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-will support tor without needing any modifications.
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-
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-2) Applications must not call gethostbyname() to resolve an address
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-they intend to later connect() to via onion routing. gethostbyname()
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-contacts the dns server of the target machine -- thus giving away the
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-fact that you intend to make an anonymous connection to it.
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-
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-To clarify, I need to explain more about the socks protocol. Socks
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-comes in three flavors: 4, 4a, and 5. The socks4 protocol basically
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-uses IP and port -- so it is unsuitable because of the gethostbyname()
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-issue above. Socks4a is a slight modification to the socks4 protocol,
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-whereby you can specify an IP of 0.0.0.x to signal the socks server
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-that you will instead be sending a hostname (fqdn). So applications with
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-socks4a support are all set. Socks5, on the other hand, allows the client
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-to specify "address type" and then an address -- so some applications
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-choose to supply an IP and others choose to supply a hostname. If the
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-application uses socks5 you must investigate further to decide whether
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-it's leaking anonymity.
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-
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-
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- Part two: using tsocks to transparently replace library calls
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-
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-tsocks (available from http://tsocks.sourceforge.net/ or from your
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-favorite apt-get equivalent) allows you to run a program as normal,
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-but it replaces the system calls for connect() to connect to the socks
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-server first and then pass it your destination info. In our case the
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-socks server is a tor process (running either locally or elsewhere).
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-In general this works quite well for command-line processes like finger,
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-ssh, etc. But there are a couple of catches: A) tsocks doesn't intercept
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-calls to gethostbyname. So unless you specify an IP rather than hostname,
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-you'll be giving yourself away. B) Programs which are suid don't let you
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-intercept the system calls -- ssh falls into this category. But you can
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-make a local copy of ssh and use that. C) Probably tsocks doesn't behave
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-well for behemoths like Mozilla.
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-
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-
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- Part three: applications which support tor correctly
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-
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-[this section is outdated and wrong. we should tie it into the main
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-tor-doc.html one day.]
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-
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-http: Mozilla: set your socks4 proxy to be the onion proxy (but see above)
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- privoxy: set your socks4a proxy to be the onion proxy
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- wget: run privoxy, and then add the line
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- "http_proxy=http://localhost:8118" to your ~/.wgetrc.
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-ssh: tsocks ssh arma@18.244.0.188
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-ftp: tsocks wget ftp://18.244.0.188/quux.tar --passive
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- Mozilla: set your socks4 proxy to be the onion proxy
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-
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Roger Dingledine