Powershell-隐藏的Windows中的键盘按键

Question

I'm in internship and I have to write a powershell script to automate a telnet script connection. I do it with cmd, I send keystroke to connect like this:

$cmd = 'C:\\Windows\\System32\\cmd.exe' Start-Process $cmd -Verb runAs $wshell = New-Object -ComObject wscript.shell; $wshell.AppActivate($cmd) Sleep 3 $wshell.SendKeys('telnet IP_ADDRESS')

And it work fine! But I have a problem...

I have to run the cmd window in a hidden style, so I have done this:

Start-Process $cmd -Verb runAs -Windowstyle hidden
$wshell = New-Object -ComObject wscript.shell;
$wshell.AppActivate($cmd) 
Sleep 3
$wshell.SendKeys('telnet IP_ADDRESS')

The window launch on a hidden style, it's ok, but the keyboard keystroke don't go in the hidden cmd window

Do anybody have a solution?

Answer 1

The problem is you're using SendKeys which literally just simulates keypresses on the keyboard. If there is no window, there is nothing to send the keypresses to.

Start-Process $cmd -ArgumentList "/K telnet IP_ADDRESS" -Verb runAs -Windowstyle hidden

This just tells CMD to run the specified command upon opening, should do the trick.

Answer 2

You can use Putty for telnet. Plink, a command line version of Putty, accepts the password on the command line. Unfortunately the telnet protocol (unlike SSH) does not have a standardized mechanism for sending the password. However you can pipe input to Plink's stdin. So you could, probably, pipe the password in to Plink.

Note that after you get logged in, you have some additional problems to consider. Since you have a hidden Window you must be planning on scripting the whole Telnet session. In order to script Telnet, you probably will need to send the input to telnet when the host program expects it. If you send all the input at once the host program/OS may not deal with it correctly. That means you probably need to do something along the lines of Tcl Expect , where you script what output to look for and then what input is sent when the expected output appears. I have seen at least one implementation of something like that in Powershell.

BTW, if you can use SSH instead of Telnet you avoid the need to pipe the password in. Piping the password in, like the Telnet protocol in general, is not secure.