ssh

ssh , short for secure shell, provides a secure shell on a remote system.

See Also

openssh

An open implementation of the secure protocol for working with remote shells.

ssh.com

Another site at least associated with source code base for SSH implementations.

Cameron Laird's personal notes on ssh

Automating sftp with Tcl

TLS

Five Minutes to a More Secure SSH

ssh and Tcl sockets , 1998-11-03

Includes an example that uses Tcl together with ssh.

multixterm

SecPanel

Serves as a GUI for managing and running SSH (Secure Shell) and SCP (Secure Copy) connections.

Description

The security infrastructure of SSH is completely separate from that of SSL.

SSH — Secure (Remote) Shell

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 — Secure Sockets Layer

Provides a secure connection without requesting login, but the server is typically expected to authenticate its identity.

ssh with sudo

This isn't directly related to Tcl, but I didn't see a simple answer anywhere else, so here is a an example of sh command to connect to a remote system and execute a command on that system as another user without exposing the password that sudo prompts for. In this example, the task is to back up the entire filesystem starting at root:

(
    printf 'Enter sudo password: ' >&2
    stty -echo; read; stty echo
    exec 3<<<"$REPLY"
    rsync -ACHXavzPie 'bash -c '\''{ cat <&3; cat -; } \
        | ssh "$@" &'\'' fakearg0forsh ' --rsync-path "sudo -S rsync" \
            --backup-dir=/path/to/backupchanged --fake-super \
            --exclude=/dev/ --exclude=/mnt/ --exclude=/proc \
            --exclude=/tmp/ --exclude=/sys \
            <username>@<host>:/ /path/to/backupdir/
)

Discussion

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 successfully to make a secure httpd tick, except I forgot how.