1 files changed, 51 insertions, 0 deletions

diff --git a/other/openssh-2.1.1p4/README.fun b/other/openssh-2.1.1p4/README.fun
new file mode 100644
index 0000000..b696aca
--- /dev/null
+++ b/other/openssh-2.1.1p4/README.fun
@@ -0,0 +1,51 @@
+Enabling reverse fun
+====================
+
+Reverse fun was 'invented' to allow users outside firewalls (which deny
+any incoming connects) or users behind masquerading routers to use ssh.
+In december 1999 on the Chaos Congress we faced the problem that the whole
+network was NATed and therefore nobody could connect to one of our
+ssh-servers. Dream-team TESO solved this problem by using scut's excellent
+'reverb' which mapped two active connections together and brought
+the client into internal network. I was very impressed and half a year
+after I patched OpenSSH to allow such things to happen without use of
+'third-party'-software. :)
+
+How it works
+------------
+
+When having reverse fun, the server (sshd) act's indeed as client and brings
+a connect to the now-server 'ssh' outside the firewall. SSH-protocol
+negotiation goes as normal then, and the user of ssh-client sees
+no difference as if (s)he would do the connect normally.
+Since the ssh-client acts as server until connect arrives,
+it blocks the user's terminal until a person (or crond:) behind the
+firewall initiates the connection.
+
+Security
+--------
+
+During reverse fun, the server must authenticate itself using
+the host-key as usual, so you can be sure the right connection arrived when
+no warning-message is placed on the screen.
+Since ssh-client runs setuid-root, reverse fun might be a danger (high-port
+bindings etc.). I've written it just for fun, and you propably shouldn't
+run this patched OpenSSH on production-machines.
+
+IPv6 support is built in, but not tested.
+
+
+Samples
+-------
+
+client:
+    sshd -r foobar -p 7350 to connect to foobar:7350 where a client must listen
+    
+server:
+    ssh -r -p 7350 to wait for incoming connects on port 7350
+
+
+When you have other funny idea's how to turn world upside down
+with programming tricks, contact me: krahmer@cs.uni-potsdam.de
+
+-Sebastian