'use strict'

/* jshint esversion: 6, asi: true, node: true */

// socket.js

// private

var debug = require('debug')

var debugWebSSH2 = require('debug')('WebSSH2')

var SSH = require('ssh2').Client

// var fs = require('fs')

// var hostkeys = JSON.parse(fs.readFileSync('./hostkeyhashes.json', 'utf8'))

var termCols, termRows

var menuData = '<a id="logBtn"><i class="fas fa-clipboard fa-fw"></i> Start Log</a>' +

'<a id="downloadLogBtn"><i class="fas fa-download fa-fw"></i> Download Log</a>'

// public

module.exports = function socket (socket) {

// if websocket connection arrives without an express session, kill it

if (!socket.request.session) {

socket.emit('401 UNAUTHORIZED')

debugWebSSH2('SOCKET: No Express Session / REJECTED')

socket.disconnect(true)

return

}

var conn = new SSH()

socket.on('geometry', function socketOnGeometry (cols, rows) {

termCols = cols

termRows = rows

})

conn.on('banner', function connOnBanner (data) {

// need to convert to cr/lf for proper formatting

data = data.replace(/\r?\n/g, '\r\n')

socket.emit('data', data.toString('utf-8'))

})

conn.on('ready', function connOnReady () {

console.log('WebSSH2 Login: user=' + socket.request.session.username + ' from=' + socket.handshake.address + ' host=' + socket.request.session.ssh.host + ' port=' + socket.request.session.ssh.port + ' sessionID=' + socket.request.sessionID + '/' + socket.id + ' mrhsession=' + socket.request.session.ssh.mrhsession + ' allowreplay=' + socket.request.session.ssh.allowreplay + ' term=' + socket.request.session.ssh.term)

socket.emit('menu', menuData)

socket.emit('allowreauth', socket.request.session.ssh.allowreauth)

socket.emit('setTerminalOpts', socket.request.session.ssh.terminal)

socket.emit('title', 'ssh://' + socket.request.session.ssh.host)

if (socket.request.session.ssh.header.background) socket.emit('headerBackground', socket.request.session.ssh.header.background)

if (socket.request.session.ssh.header.name) socket.emit('header', socket.request.session.ssh.header.name)

socket.emit('footer', 'ssh://' + socket.request.session.username + '@' + socket.request.session.ssh.host + ':' + socket.request.session.ssh.port)

socket.emit('status', 'SSH CONNECTION ESTABLISHED')

socket.emit('statusBackground', 'green')

socket.emit('allowreplay', socket.request.session.ssh.allowreplay)

conn.shell({

term: socket.request.session.ssh.term,

cols: termCols,

rows: termRows

}, function connShell (err, stream) {

if (err) {

SSHerror('EXEC ERROR' + err)

conn.end()

return

}

// poc to log commands from client

if (socket.request.session.ssh.serverlog.client) var dataBuffer

socket.on('data', function socketOnData (data) {

stream.write(data)

// poc to log commands from client

if (socket.request.session.ssh.serverlog.client) {

if (data === '\r') {

console.log('serverlog.client: ' + socket.request.session.id + '/' + socket.id + ' host: ' + socket.request.session.ssh.host + ' command: ' + dataBuffer)

dataBuffer = undefined

} else {

dataBuffer = (dataBuffer) ? dataBuffer + data : data

}

}

})

socket.on('control', function socketOnControl (controlData) {

switch (controlData) {

case 'replayCredentials':

if (socket.request.session.ssh.allowreplay) {

stream.write(socket.request.session.userpassword + '\n')

}

/* falls through */

default:

console.log('controlData: ' + controlData)

}

})

socket.on('resize', function socketOnResize (data) {

stream.setWindow(data.rows, data.cols)

})

socket.on('disconnecting', function socketOnDisconnecting (reason) { debugWebSSH2('SOCKET DISCONNECTING: ' + reason) })

socket.on('disconnect', function socketOnDisconnect (reason) {

debugWebSSH2('SOCKET DISCONNECT: ' + reason)

err = { message: reason }

SSHerror('CLIENT SOCKET DISCONNECT', err)

conn.end()

// socket.request.session.destroy()

})

socket.on('error', function socketOnError (err) {

SSHerror('SOCKET ERROR', err)

conn.end()

})

stream.on('data', function streamOnData (data) { socket.emit('data', data.toString('utf-8')) })

stream.on('close', function streamOnClose (code, signal) {

err = { message: ((code || signal) ? (((code) ? 'CODE: ' + code : '') + ((code && signal) ? ' ' : '') + ((signal) ? 'SIGNAL: ' + signal : '')) : undefined) }

SSHerror('STREAM CLOSE', err)

conn.end()

})

stream.stderr.on('data', function streamStderrOnData (data) {

console.log('STDERR: ' + data)

})

})

})

conn.on('end', function connOnEnd (err) { SSHerror('CONN END BY HOST', err) })

conn.on('close', function connOnClose (err) { SSHerror('CONN CLOSE', err) })

conn.on('error', function connOnError (err) { SSHerror('CONN ERROR', err) })

conn.on('keyboard-interactive', function connOnKeyboardInteractive (name, instructions, instructionsLang, prompts, finish) {

debugWebSSH2('conn.on(\'keyboard-interactive\')')

finish([socket.request.session.userpassword])

})

if (socket.request.session.username && socket.request.session.userpassword && socket.request.session.ssh) {

// console.log('hostkeys: ' + hostkeys[0].[0])

conn.connect({

host: socket.request.session.ssh.host,

port: socket.request.session.ssh.port,

username: socket.request.session.username,

password: socket.request.session.userpassword,

tryKeyboard: true,

algorithms: socket.request.session.ssh.algorithms,

readyTimeout: socket.request.session.ssh.readyTimeout,

keepaliveInterval: socket.request.session.ssh.keepaliveInterval,

keepaliveCountMax: socket.request.session.ssh.keepaliveCountMax,

debug: debug('ssh2')

})

} else {

debugWebSSH2('Attempt to connect without session.username/password or session varialbles defined, potentially previously abandoned client session. disconnecting websocket client.\r\nHandshake information: \r\n ' + JSON.stringify(socket.handshake))

socket.emit('ssherror', 'WEBSOCKET ERROR - Refresh the browser and try again')

socket.request.session.destroy()

socket.disconnect(true)

}

/**

* Error handling for various events. Outputs error to client, logs to

* server, destroys session and disconnects socket.

* @param {string} myFunc Function calling this function

* @param {object} err error object or error message

*/

function SSHerror (myFunc, err) {

var theError

if (socket.request.session) {

// we just want the first error of the session to pass to the client

socket.request.session.error = (socket.request.session.error) || ((err) ? err.message : undefined)

theError = (socket.request.session.error) ? ': ' + socket.request.session.error : ''

// log unsuccessful login attempt

if (err && (err.level === 'client-authentication')) {

console.log('WebSSH2 ' + 'error: Authentication failure'.red.bold +

' user=' + socket.request.session.username.yellow.bold.underline +

' from=' + socket.handshake.address.yellow.bold.underline)

socket.emit('allowreauth', socket.request.session.ssh.allowreauth)

socket.emit('reauth')

} else {

console.log('WebSSH2 Logout: user=' + socket.request.session.username + ' from=' + socket.handshake.address + ' host=' + socket.request.session.ssh.host + ' port=' + socket.request.session.ssh.port + ' sessionID=' + socket.request.sessionID + '/' + socket.id + ' allowreplay=' + socket.request.session.ssh.allowreplay + ' term=' + socket.request.session.ssh.term)

if (err) {

theError = (err) ? ': ' + err.message : ''

console.log('WebSSH2 error' + theError)

}

}

socket.emit('ssherror', 'SSH ' + myFunc + theError)

socket.request.session.destroy()

socket.disconnect(true)

} else {

theError = (err) ? ': ' + err.message : ''

socket.disconnect(true)

}

debugWebSSH2('SSHerror ' + myFunc + theError)

}

}