observer.py

from google.cloud.firestore_v1.base_query import FieldFilter
from firebase_admin import credentials
from firebase_admin import firestore
import firebase_admin
import socket
import json
from scapy.all import *

# firebase variables
fbCred = credentials.Certificate('./firebaseCredential.json')
app = firebase_admin.initialize_app(fbCred)
nodeRef = firestore.client().collection("module")

# socket variables
sendSocket = socket.socket(socket.AF_INET6, socket.SOCK_DGRAM)
port = 61617

# observer variables
uidToIp = {}
observerId = 0

def ipFormat(ipList):
    converted = []
    for i in range(0,8): converted.append(ipList[2*i] + ipList[2*i+1])
    return ':'.join(converted[:4]) + "::" + ':'.join(converted[5:])

def registerNode(unique_id): nodeRef.document(unique_id).set({"connected": False, "observerId": observerId, "isBlocked": True})

def documnetEventListener(col_snapshot, changes, read_time):
    for change in changes:
        if change.type.name == "MODIFIED":
            msg = 0 if change.document.get("isBlocked") else 1
            dst = uidToIp[change.document.id]
            sendToNode(dst, msg)

def updateDocument(mac, isOccupied): nodeRef.document(mac).update({"isOccupied": isOccupied})

def packetLoadToHex(original_s):
    s = str(original_s)[2:-1]
    hexList = []

    i = 0
    while i < len(s):
        if s[i: i+2] == "\\x":
            hexList.append( s[i+2: i+4] )
            i += 4
        elif s[i: i+2] == "\\r":
            hexList.append( "0d" )
            i += 2
        else:
            hexList.append( hex(ord(s[i]))[2:] )
            i += 1
    return hexList

def handlePacket(rowPacket):
    pk = rowPacket[0]
    src_ip = pk[1].src; src_mac = pk[0].src
    dst_ip = pk[1].dst; dst_mac = pk[0].dst

    if "2001" not in dst_ip: return

    if hasattr(pk[3], "load"):
        load = str(pk[3].load)
        hexList = packetLoadToHex(pk[3].load)
        
        if ("check_reception" in load) and (len(load) == 26):
            unique_id = load[-5:-1]
            if(unique_id not in uidToIp):
                registerNode(unique_id)
                uidToIp[unique_id] = src_ip
                print(unique_id + " registered")

            isOccupied = (hexList[0] == '01')
            updateDocument(unique_id, isOccupied)

def sendToNode(dst, msg):
    print("sendToNode")
    sendSocket.connect((dst, port))
    sendSocket.send(msg.to_bytes(1, 'big'))


# run
col_query = nodeRef.where(filter=FieldFilter("observerId", "==", observerId))
query_watch = col_query.on_snapshot(documnetEventListener)

# while True:
sniff(iface="wisun", prn = handlePacket, count = 0)
    # quit = input("type q if you want quit this : ")
    # break;  
sendSocket.close()