ncouture / mockssh

Mock an SSH server and define all commands it supports (Python, Twisted)

MockSSH

Mock an SSH server and all commands it supports.

Purpose

This project was developed to emulate operating systems behind SSH servers in order to test task automation without having access to the real servers.

There has been user interest in using MockSSH to perform end-to-end unit tests against SSH servers and as such a threaded version of MockSSH server is available as of version 1.4 (thanks to Claudio Mignanti).

Installation

MockSSH depends on libraries that do not support Python 3k.

mkvirtualenv -p `which python2` mocksshenv
pip install mockssh

MockSSH in Python

MockSSH aims to be as easy to use as possible.

Refer to the mock_cisco.py and mock_F5.py in the examples/ directory for an overview on how to use it.

MockSSH in LISP

Efforts were invested in simplifying the use of MockSSH with HyLang.

As a result a DSL is released with this project and resides in the mocksshy/ directory.

Using the DSL will allow you to use MockSSH by writing something that is closer to a configuration file than a program.

For comparison, here are two MockSSH servers implementations providing the same functionality:

Python

import MockSSH

def passwd_change_protocol_prompt(instance):
    instance.protocol.prompt = "hostname #"
    instance.protocol.password_input = False

def passwd_write_password_to_transport(instance):
    instance.writeln("MockSSH: password is %s" % instance.valid_password)

command_passwd = MockSSH.PromptingCommand(
    name='passwd',
    password='1234',
    prompt="Password: ",
    success_callbacks=[passwd_change_protocol_prompt],
    failure_callbacks=[passwd_write_password_to_transport])

users = {'admin': '1234'}

commands = [command_passwd]

MockSSH.runServer(commands,
                  prompt="hostname>",
                  interface='127.0.0.1',
                  port=2222,
                  **users)

HyLang

(import MockSSH)
(require mocksshy.language)


(mock-ssh :users {"testuser" "1234"}
          :host "127.0.0.1"
          :port 2222
          :prompt "hostname>"
          :commands [
  (command :name "passwd"
           :type "prompt"
           :output "Password: "
           :required-input "1234"
           :on-success ["prompt" "hostname#"]
           :on-failure ["write" "Pass is 1234..."]))

Unit Testing with MockSSH

As shown from the unit tests in the tests/ directory, it is possible to use a threaded MockSSH server to perform end-to-end unit tests against mocked SSH services.

Note that this may not be the right approach depending on your use case as only one Twisted reactor can run at the same time and reactors cannot be restarted.

Credits

MockSSH is derived from kippo, an SSH honeypot.