Version 25 of ssh

Updated 2008-03-20 05:38:57 by Justis

Purpose: describe what ssh is, where to find it, and what connections to Tcl it has.

http://en.wikipedia.org/wiki/Secure_Shell is a good place to start.

Note that the security infrastructure of SSH is completely separate from that of SSL.

SSH
is typically used to connect securely to a machine where you have an account. At heart, it is a "secure telnet" which however can carry lots of other traffic (forwarded IP ports, file transfers) within the encrypted connection.
SSL
provides a secure connection without requesting login, but the server is typically expected to authenticate its identity.

See http://www.openssh.org/ for an open implementation of the secure protocol for starting shell commands across an inter/intranet. http://www.ssh.com/ is another site at least associated with source code base for SSH implementations.

http://www.phaseit.net/claird/comp.security.ssh/ssh.html may also be of interest.


Anyone know of a Tcl extension binding to one of the ssh libraries?

Perhaps D. J. Hagberg's example of port forwarding, from 1998 [L1 ] is useful.

CMcC I've thrown together some code to allow remote ssh tcl execution.

hkoba: You can also use comm via ssh to send/eval any script to remote host.

AMG: I whipped up a Tcl script that allows you to ssh to multiple hosts at the same time, using a single command and a single set of stdin/stdout/stderr. Try running bash with it, heh heh. (It really works!) For details, see multissh.

Justis: The TclCURL library seems to have some SSH features compiled into it: [L2 ]


Russell Treleaven reports [L3 ] that he successfully automates ssh client sessions on a Windows host with ActiveState's Expect and the ssh2 executable [L4 ]. He uses the "send slow" option. Both of these applications are proprietary.


TV I've within some limitations, used the cygwin ssh facility, which is quite extensive, except varying from a drag to requiring out of package documentation to install. It is almost unix, though. It also contains working executables to use openSSL to create and deal with certificates, I used it succesfully to make a secure httpd tick, except I forgot how.


See also: Automating sftp with Tcl, TLS

"Five Minutes to a More Secure SSH" [L5 ]


http://groups.google.com/groups?oi=djq&selm=an_408378721 shows an example of using tcl and ssh.