Having read this question and my answer there, I would like to do a similar thing on Windows.
My Linux solution is this:
#!/bin/bash
[[ $1 =~ password: ]] && cat || SSH_ASKPASS="$0" DISPLAY=nothing:0 exec setsid "$@"
How can I do a similar thing on Windows, something I can use like this from a Windows Command Prompt or batch file:
C:> echo password | pass ssh user@host ...
Points to note:
sshhere was installed using the free edition of crwsync. It uses Cygwin DLLs but does not require a Cygwin install.- the solution should not require further dependencies: it work from a typical Windows Command Prompt or batch file.
I'm looking for an answer to the above, even if the answer is "it can't be done". I know I can use keys (and their relative merits), or other tools such as Python/Paramiko, PuTTY plink, and so-on. I know I can do it in a Cygwin environment. I don't want to do those things... I need to do it from a plain old Windows command prompt or batch file without incurring additional dependencies because, if this is possible, it will reduce existing dependencies.
Here is what I have so far:
@echo off
echo.%1 | findstr /C:"password">nul
if errorlevel 1 (
set SSH_ASKPASS="%0"
set DISPLAY="nothing:0"
%*
) else (
findstr "^"
)
The idea is to save that as, say pass.bat and use it like this:
C:> echo password | pass.bat ssh user@host ...
What happens is that the SSH session is launched but ssh still interactively prompts for the password. I think that, in theory, the script is ok becuse the below works:
C:> echo mypassword | pass.bat pass.bat "password"
mypassword
As far as I understand, the underlying Cygwin DLLs should see the Windows environment so the setting of SSH_ASKPASS should propagate into ssh.
I think the problem is that ssh is connected to the terminal. According to man ssh, If ssh needs a passphrase, it will read the passphrase from the current terminal if it was run from a terminal. This is why I use setsid in the Linux example. I think a way to detach the process from the terminal in Windows is required but I am not sure there is one (I did try start /B).
So I'm stuck - I don't know enough about scripting windows to know what should work. Any solution that uses native windows techniques (i.e. batch or perhaps powershell) and does not require anything not available on a vanilla Windows would be welcome.
The solution will be used by a cross platform application that I am working on that needs to use SSH to interact with an external service. The current prototype version is Python and is aready wired up to launch ssh as a subprocess. The Linux version already uses the above method so I would like a Windows solution that does not require reworking of the application.
