Panasonic Viera TV IP control

[benanderson_475]

Try these functions, they are untested so might not work at all. You have to parse any XML response manually

Code:

function request(host, url, urn, action, args)
  local body, http, ltn12, sink, res, err

  ltn12 = require('ltn12')
  http = require('socket.http')
  body = [[<?xml version="1.0" encoding="utf-8"?>
  <s:Envelope xmlns:s="http://schemas.xmlsoap.org/soap/envelope/" s:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/">
  <s:Body><u:]] .. action .. [[ xmlns:u="urn:]] .. urn .. [[">]] .. args .. [[</u:]] .. action .. [[></s:Body>
  </s:Envelope>]]

  sink = {}

  res, err = http.request({
    url = 'http://' .. host .. ':55000/' .. url,
    method = 'POST',
    headers = {
      ['soapaction'] = '"urn:' .. urn .. '#' .. action .. '"',
      ['Content-Length'] = #body,
    },
    sink = ltn12.sink.table(sink),
    source = ltn12.source.string(body),
  })

  if res then
    return table.concat(sink)
  else
    return nil, err
  end
end

function sendkey(host, code)
  local args = '<X_KeyEvent>' .. code .. '</X_KeyEvent>'
  return request(host, 'nrc/control_0', 'panasonic-com:service:p00NetworkControl:1', 'X_SendKey', args)
end

function getmute(host)
  return request(host, 'dmr/control_0', 'schemas-upnp-org:service:RenderingControl:1', 'GetMute', '<InstanceID>0</InstanceID><Channel>Master</Channel>')
end

IP = '192.168.1.2'
log(getmute(IP))

Now in my region as of 2019 Panasonic have implemented Auth before i can send commands, 
i found this (https://github.com/florianholzapfel/pana...a/issues/9) explaining how it is achieved, but it is python, im not sure where to start to work out how to port it to lua,
I have soap command working to return the iv key my goal is to return the encrypted_payload to send to the tv to make connection.

import binascii
import base64
import hmac, hashlib
from Crypto.Cipher import AES

# Example challenge (which is our IV)
iv = base64.b64decode("mUQdS7/RyJTMsiojPz9i1Q==")

# Get character codes from IV bytes
iv_vals = [ord© for c in iv]

# Initialise key character codes array
key_vals = [0] * 16

# Derive key from IV
i = 0
while i < 16:
    key_vals[i] = ~iv_vals[i + 3] & 0xFF
    key_vals[i + 1] = ~iv_vals[i + 2] & 0xFF
    key_vals[i + 2] = ~iv_vals[i + 1] & 0xFF
    key_vals[i + 3] = ~iv_vals[i] & 0xFF
    i += 4

# Convert our key character codes to bytes
key = ''.join(chr© for c in key_vals)

# Initialise HMAC key mask (taken from libtvconnect.so)
hmac_key_mask_vals = [ord© for c in binascii.unhexlify("15C95AC2B08AA7EB4E228F811E34D04FA54BA7DCAC9879FA8ACDA3FC244F3854")]

# Initialise HMAC key character codes array
hmac_vals = [0] * 32

# Calculate HMAC key using HMAC key mask and IV
i = 0
while i < 32:
    hmac_vals[i] = hmac_key_mask_vals[i] ^ iv_vals[(i + 2) & 0xF]
    hmac_vals[i + 1] = hmac_key_mask_vals[i + 1] ^ iv_vals[(i + 3) & 0xF]
    hmac_vals[i + 2] = hmac_key_mask_vals[i + 2] ^ iv_vals[i & 0xF]
    hmac_vals[i + 3] = hmac_key_mask_vals[i + 3] ^ iv_vals[(i + 1) & 0xF]
    i += 4

# Convert our HMAC key character codes to bytes
hmac_key = ''.join(chr© for c in hmac_vals)

# This is our plaintext SOAP argument for the pin code shown on the TV
authinfo = "<X_PinCode>4410</X_PinCode>"

# First 12 bytes are randomised, let's just set them to 0 because it doesn't matter
payload = "000000000000"

# The next 4 bytes contain the plaintext (SOAP arg) length in big endian
n = len(authinfo)
payload += chr(n >> 24)
payload += chr((n >> 16) & 0xFF)
payload += chr((n >> 8) & 0xFF)
payload += chr(n & 0xFF)

# Now we concatenate our payload, which is starting at byte 17 of the payload
payload += authinfo

# Let's encrypt it with AES-CBC! We need to make sure we pad it to a multiple of 16 bytes beforehand
aes = AES.new(key, AES.MODE_CBC, iv)
ciphertext = aes.encrypt(pad(payload))

# Calculate the HMAC-SHA-256 signature of our encrypted payload
sig = hmac.new(hmac_key, ciphertext, hashlib.sha256).digest()

# Concatenate the HMAC signature to the encrypted payload and base64 encode it, and we're done!
encrypted_payload = base64.b64encode(ciphertext + sig)