Feeding input to an interactive command line application

Question

I'd like to feed inputs to a command line interface for Cisco AnyConnect vpncli.exe (v2.3) to automate its (re)connection. It does not take username nor password as command line arguments, but reads those interactively from the user via the command line interface.

Problem is that piping input to vpncli.exe doesn't seem to work for the password. It works for everything except the password. So doing things like this doesn't work:

vpncli.exe < input.txt
type input.txt | vpncli.exe

The application just gets stuck at where it asks for the password.

Below is an example of normal (working) execution where the user enters the parameters:

Notice how the password characters get transformed to *.

Using tools like AutoIt or AutoHotKey to send the inputs to a command prompt window works, but is clumsy and fragile (does not work if the tool can't get to the command prompt window for some reason).

Is there any way to send inputs to such interactive CLI application using PowerShell?

(Or using any other scripting language or some other means?)

Solution 1

There are at least two ways to read input in a Windows console application.

• ReadConsole: reads input either from keyboard or redirection (documentation).
• ReadConsoleInput: reads only raw keystrokes (documentation).

The vpncli.exe application uses ReadConsoleInput in order to read the password, that's way redirecting the password does not work. You can, though, use WriteConsoleInput. I have a small Python script that does exactly that:

import subprocess
import win32console

ANYCONNECT_BIN = 'c:\\Program Files\\Cisco\\Cisco AnyConnect Secure Mobility Client\\vpncli.exe'

def write_console_input(text):
  stdin = win32console.GetStdHandle(win32console.STD_INPUT_HANDLE)
  ir = win32console.PyINPUT_RECORDType(win32console.KEY_EVENT)
  ir.KeyDown = True
  for ch in text:
    ir.Char = unicode(ch)
    stdin.WriteConsoleInput([ir])

def main():
  proc = subprocess.Popen([ANYCONNECT_BIN,'connect','VPN'],stdin=subprocess.PIPE)
  proc.stdin.write('%s\n%s\n' % ('GROUP', 'USERNAME'))
  write_console_input('%s\n' % 'PASSWORD')
  ret = proc.wait()
  print ret

if __name__ == '__main__':
  main()

Solution 2

you need to create an usual text file like

connect myvpnhost
myloginname
mypassword

save it as myfile.dat (for example) and then call

"%ProgramFiles%\Cisco\Cisco AnyConnect Secure Mobility Client\vpncli.exe" -s < myfile.dat

Comments

[Angshuman Agarwal]

Will this help - joshuasjohnson.com/how-to-script-a-login-for-a-cisco-vpn-cli‌​ent

[Qtax]

@AngshumanAgarwal, unfortunately no, it's a different version of VPN client.

[x0n]

Try wasp.codeplex.com - try to send keystrokes to the console window.

[Qtax]

Thanks, good info/ref and example. Altho I ended up using ControlSend with AHK to send keystrokes to the console window (which works fine even if window is minimized, etc).

[Qtax]

In the question I stated that exactly this does not work. Or are you saying that the -s flag makes it work? What does that flag do?

[George Hazan]

yes, -s flag simply expands the stdin (<) to the console. it works for me ideally for about a year

[George Hazan]

if you don't trust me, simply run vpncli.exe /? :-)

[josephpconley]

Using Cisco AnyConnect Secure Mobility Client (version 3.0.08057), the -s flag is no longer an option (thus this answer doesn't work), are there any other workarounds?