#!/usr/bin/env python

"""
Tests for baresshd.py
"""

import unittest
import pexpect
from mininet.clean import cleanup, sh

class testBareSSHD( unittest.TestCase ):

    opts = [ 'Welcome to h1', pexpect.EOF, pexpect.TIMEOUT ]

    def connected( self ):
        "Log into ssh server, check banner, then exit"
        p = pexpect.spawn( 'ssh 10.0.0.1 -o StrictHostKeyChecking=no -i /tmp/ssh/test_rsa exit' )
        while True:
            index = p.expect( self.opts )
            if index == 0:
                return True
            else:
                return False

    def setUp( self ):
        # verify that sshd is not running
        self.assertFalse( self.connected() )
        # create public key pair for testing
        sh( 'rm -rf /tmp/ssh' )
        sh( 'mkdir /tmp/ssh' )
        sh( "ssh-keygen -t rsa -P '' -f /tmp/ssh/test_rsa" )
        sh( 'cat /tmp/ssh/test_rsa.pub >> /tmp/ssh/authorized_keys' )
        # run example with custom sshd args
        cmd = ( 'python -m mininet.examples.baresshd '
                '-o AuthorizedKeysFile=/tmp/ssh/authorized_keys '
                '-o StrictModes=no' )
        p = pexpect.spawn( cmd )
        runOpts = [ 'You may now ssh into h1 at 10.0.0.1',
                    'after 5 seconds, h1 is not listening on port 22', 
                    pexpect.EOF, pexpect.TIMEOUT ]
        while True:
            index = p.expect( runOpts )
            if index == 0:
                break
            else:
                self.tearDown()
                self.fail( 'sshd failed to start in host h1' )

    def testSSH( self ):
        "Simple test to verify that we can ssh into h1"
        result = False
        # try to connect up to 3 times; sshd can take a while to start
        result = self.connected()
        self.assertTrue( result )

    def tearDown( self ):
        # kill the ssh process
        sh( "ps aux | grep 'ssh.*Banner' | awk '{ print $2 }' | xargs kill" )
        cleanup()
        # remove public key pair
        sh( 'rm -rf /tmp/ssh' )

if __name__ == '__main__':
    unittest.main()