SSH LocalForward

Kristof Van Damme (aeneas@sesuadra.org)
Sat, 02 Aug 1997 16:33:51 +0200

Hi,

I bumped into a weird 'feature' of ssh 1.2.20. When I run:

ssh -L 80:remotehost:80 remotehost

as a normal user I get the expected error:

Privileged ports can only be forwarded by root.

But when I put:

LocalForward 80 remotehost:80

in my ~/.ssh/config file and connect to the remote host I don't get the
error and port 80 is opened on the localhost (an httpd was not running,
the port must be available). When I connect to it I get a normal
redirection to remotehost:80 over the secure channel. This means however
that a non-root user is able to open privileged ports on the localhost and
redirect them. Is this normal? I checked it on Linux and Solaris.

Aeneas
----------------------------------------------------------------------
|Kristof Van Damme |
|System Administrator |
|e-mail: aeneas@sesuadra.org |
|voice: +32 9 3558603 |
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