TCP Socket Connection for Legrand

[admin]

Try this, change PASS and IP as needed. The script handles the authentication part, after that you can issue commands, read status info etc.

Code:

function calcpass(pass, nonce)
  local flag = true
  local num1 = 0
  local num2 = 0
  local password = tonumber(pass, 10)

  for i = 1, #nonce do
    local c = nonce:sub(i, i)

    if c ~= '0' then
      if flag then
        num2 = password
      end

      flag = false
    end

    if c == '1' then
      num1 = bit.band(num2, 0xFFFFFF80)
      num1 = bit.rshift(num1, 7)
      num2 = bit.lshift(num2, 25)
      num1 = num1 + num2
    elseif c == '2' then
      num1 = bit.band(num2, 0xFFFFFFF0)
      num1 = bit.rshift(num1, 4)
      num2 = bit.lshift(num2, 28)
      num1 = num1 + num2
    elseif c == '3' then
      num1 = bit.band(num2, 0xFFFFFFF8)
      num1 = bit.rshift(num1, 3)
      num2 = bit.lshift(num2, 29)
      num1 = num1 + num2
    elseif c == '4' then
      num1 = bit.lshift(num2, 1)
      num2 = bit.rshift(num2, 31)
      num1 = num1 + num2
    elseif c == '5' then
      num1 = bit.lshift(num2, 5)
      num2 = bit.rshift(num2, 27)
      num1 = num1 + num2
    elseif c == '6' then
      num1 = bit.lshift(num2, 12)
      num2 = bit.rshift(num2, 20)
      num1 = num1 + num2
    elseif c == '7' then
      num1 = bit.band(num2, 0x0000FF00)
      num1 = num1 + bit.lshift(bit.band(num2, 0x000000FF), 24)
      num1 = num1 + bit.rshift(bit.band(num2, 0x00FF0000), 16)
      num2 = bit.rshift(bit.band(num2, 0xFF000000), 8)
      num1 = num1 + num2
    elseif c == '8' then
      num1 = bit.band(num2, 0x0000FFFF)
      num1 = bit.lshift(num1, 16)
      num1 = num1 + bit.rshift(num2, 24)
      num2 = bit.band(num2, 0x00FF0000)
      num2 = bit.rshift(num2, 8)
      num1 = num1 + num2
    elseif c == '9' then
      num1 = bit.bnot(num2)
    elseif c == '0' then
      num1 = num2
    end

    num2 = num1
  end

  if num1 < 0 then
    num1 = num1 + 4294967296
  end

  return tostring(num1)
end

function read(sock)
  local buf = {}

  while true do
    local ch, err = sock:receive(1)

    if ch then
      local pr = buf[ #buf ]

      buf[ #buf + 1 ] = ch

      if ch == '#' and pr == '#' then
        break
      end

    else
      return nil, err
    end
  end

  return table.concat(buf)
end

ACK = '*#*1##'
NACK = '*#*0##'
OPEN = '*99*0##'

PASS = '12345'
IP = '127.0.0.1'
PORT = 20000

function openwebnetinit()
  local sock = require('socket').tcp()
  local res, err

  sock:settimeout(1)

  res, err = sock:connect(IP, PORT)
  if not res then
    alert('connect failed ' .. tostring(err))
    return
  end

  res, err = read(sock)
  if res ~= ACK then
    alert('no initial ack ' .. tostring(res or err))
    return
  end

  sock:send(OPEN)

  res, err = read(sock)
  if not res then
    alert('no nonce ' .. tostring(err))
    return
  end

  local nonce = res:match('%d+')
  local pass = calcpass(PASS, nonce)

  sock:send('*#' .. pass .. '##')

  res, err = read(sock)
  if res ~= ACK then
    alert('auth failed ' .. tostring(res or err))
    return
  end

  return sock
end

sock = openwebnetinit()
if sock then
  alert('connection ok')
  -- do something here
  sock:close()
end