-#!/usr/bin/python
-
-"""
-Script that constructs a graph in which hosts are nodes.
-An edge between two hosts indicate that the hosts communicate.
-Hosts are labeled and identified by their IPs.
-The graph is written to a file in Graph Exchange XML format for later import and visual inspection in Gephi.
-
-Update per February 2, 2018:
-Extension of base_gefx_generator.py.
-This script constructs a bipartite graph with IoT devices on one side and Internet hosts on the other side.
-As a result, this graph does NOT show inter IoT device communication.
-
-The input to this script is the JSON output by extract_from_tshark.py by Anastasia Shuba.
-
-This script is a simplification of Milad Asgari's parser_data_to_gephi.py script.
-It serves as a baseline for future scripts that want to include more information in the graph.
-"""
-
-import socket
-import json
-import tldextract
-import networkx as nx
-import sys
-import csv
-import re
-import parser.parse_dns
-from decimal import *
-from networkx.algorithms import bipartite
-
-# List of devices
-DEVICE_MAC_LIST = "devicelist.dat"
-EXCLUSION_MAC_LIST = "exclusion.dat"
-COLUMN_MAC = "MAC_address"
-COLUMN_DEVICE_NAME = "device_name"
-# Fields
-JSON_KEY_SOURCE = "_source"
-JSON_KEY_LAYERS = "layers"
-JSON_KEY_FRAME = "frame"
-JSON_KEY_FRAME_PROTOCOLS = "frame.protocols"
-JSON_KEY_FRAME_TIME_EPOCH = "frame.time_epoch"
-JSON_KEY_FRAME_LENGTH = "frame.len"
-JSON_KEY_ETH = "eth"
-JSON_KEY_ETH_SRC = "eth.src"
-JSON_KEY_ETH_DST = "eth.dst"
-JSON_KEY_IPV6 = "ipv6"
-JSON_KEY_IP = "ip"
-JSON_KEY_IP_SRC = "ip.src"
-JSON_KEY_IP_DST = "ip.dst"
-# Checked protocols
-JSON_KEY_UDP = "udp"
-JSON_KEY_TCP = "tcp"
-# List of checked protocols
-listchkprot = [ "arp",
- "bootp",
- "dhcpv6",
- "dns",
- "llmnr",
- "mdns",
- "ssdp" ]
-
-# Switch to generate graph that only shows local communication
-ONLY_INCLUDE_LOCAL_COMMUNICATION = False
-
-
-def create_device_list(dev_list_file):
- """ Create list for smart home devices from a CSV file
- Args:
- dev_list_file: CSV file path that contains list of device MAC addresses
- """
- # Open the device MAC list file
- with open(dev_list_file) as csvfile:
- mac_list = csv.DictReader(csvfile, (COLUMN_MAC, COLUMN_DEVICE_NAME))
- crude_list = list()
- for item in mac_list:
- crude_list.append(item)
- # Create key-value dictionary
- dev_list = dict()
- for item in crude_list:
- dev_list[item[COLUMN_MAC]] = item[COLUMN_DEVICE_NAME]
- #print item["MAC_address"] + " => " + item["device_name"]
- #for key, value in devlist.iteritems():
- # print key + " => " + value
-
- return dev_list
-
-
-def traverse_and_merge_nodes(G, dev_list_file):
- """ Merge nodes that have similar properties, e.g. same protocols
- But, we only do this for leaves (outer nodes), and not for
- nodes that are in the middle/have many neighbors.
- The pre-condition is that the node:
- (1) only has one neighbor, and
- (2) not a smarthome device.
- then we compare the edges, whether they use the same protocols
- or not. If yes, then we collapse that node and we attach
- it to the very first node that uses that set of protocols.
- Args:
- G: a complete networkx graph
- dev_list_file: CSV file path that contains list of device MAC addresses
- """
- nodes = G.nodes()
- #print "Nodes: ", nodes
- node_to_merge = dict()
- # Create list of smarthome devices
- dev_list = create_device_list(DEVICE_MAC_LIST)
- # Traverse every node
- # Check that the node is not a smarthome device
- for node in list(nodes):
- neighbors = G[node] #G.neighbors(node)
- #print "Neighbors: ", neighbors, "\n"
- # Skip if the node is a smarthome device
- if node in dev_list:
- continue
- # Skip if the node has many neighbors (non-leaf) or no neighbor at all
- if len(neighbors) is not 1:
- continue
- #print "Node: ", node
- neighbor = neighbors.keys()[0] #neighbors[0]
- #print "Neighbor: ", neighbors
- protocols = G[node][neighbor]['Protocol']
- #print "Protocol: ", protocols
- # Store neighbor-protocol as key in dictionary
- neigh_proto = neighbor + "-" + protocols
- if neigh_proto not in node_to_merge:
- node_to_merge[neigh_proto] = node
- else:
- # Merge this node if there is already an entry
- # First delete
- G.remove_node(node)
- node_to_merge_with = node_to_merge[neigh_proto]
- merged_nodes = G.node[node_to_merge_with]['Merged']
- # Check if this is the first node
- if merged_nodes is '':
- merged_nodes = node
- else:
- # Put comma if there is already one or more nodes
- merged_nodes += ", " + node
- # Then attach as attribute
- G.node[node_to_merge_with]['Merged'] = merged_nodes
-
- return G
-
-
-def place_in_graph(G, eth_src, eth_dst, device_dns_mappings, dev_list, layers,
- edge_to_prot, edge_to_vol):
- """ Place nodes and edges on the graph
- Args:
- G: the complete graph
- eth_src: MAC address of source
- eth_dst: MAC address of destination
- device_dns_mappings: device to DNS mappings (data structure)
- dev_list: list of existing smarthome devices
- layers: layers of JSON file structure
- edge_to_prot: edge to protocols mappings
- edge_to_vol: edge to traffic volume mappings
- """
- # Get timestamp of packet (router's timestamp)
- timestamp = Decimal(layers[JSON_KEY_FRAME][JSON_KEY_FRAME_TIME_EPOCH])
- # Get packet length
- packet_len = Decimal(layers[JSON_KEY_FRAME][JSON_KEY_FRAME_LENGTH])
- # Get the protocol and strip just the name of it
- long_protocol = layers[JSON_KEY_FRAME][JSON_KEY_FRAME_PROTOCOLS]
- # Split once starting from the end of the string and get it
- split_protocol = long_protocol.split(':')
- protocol = None
- if len(split_protocol) < 5:
- last_index = len(split_protocol) - 1
- protocol = split_protocol[last_index]
- else:
- protocol = split_protocol[3] + ":" + split_protocol[4]
- #print "timestamp: ", timestamp, " - new protocol added: ", protocol, "\n"
- # And source and destination IPs
- ip_src = layers[JSON_KEY_IP][JSON_KEY_IP_SRC]
- ip_dst = layers[JSON_KEY_IP][JSON_KEY_IP_DST]
- # Categorize source and destination IP addresses: local vs. non-local
- #ip_re = re.compile(r'\b192.168.[0-9.]+')
- ip_re = re.compile(r'\b192.168.1.[0-9.]+')
- src_is_local = ip_re.search(ip_src)
- dst_is_local = ip_re.search(ip_dst)
- # Store protocol into the set (source)
- protocols = None
- # Key to search in the dictionary is <src-mac-address>-<dst-mac_address>
- dict_key = ip_src + "-" + ip_dst
- #print "Key: ", dict_key
- if dict_key not in edge_to_prot:
- edge_to_prot[dict_key] = set()
- protocols = edge_to_prot[dict_key]
- protocols.add(protocol)
- protocols_str = ', '.join(protocols)
- #print "protocols: ", protocols_str, "\n"
- # Check packet length and accumulate to get traffic volume
- if dict_key not in edge_to_vol:
- edge_to_vol[dict_key] = 0;
- edge_to_vol[dict_key] = edge_to_vol[dict_key] + packet_len
- volume = str(edge_to_vol[dict_key])
-
- # Skip device to cloud communication if we are interested in the local graph.
- # TODO should this go before the protocol dict is changed?
- if ONLY_INCLUDE_LOCAL_COMMUNICATION and not (src_is_local and dst_is_local):
- return
-
- #print "ip.src =", ip_src, "ip.dst =", ip_dst, "\n"
- # Place nodes and edges
- src_node = None
- dst_node = None
- # Integer values used for tagging nodes, indicating to Gephi if they are local IoT devices or web servers.
- remote_node = 0
- local_node = 1
- # Values for the 'bipartite' attribute of a node when constructing the bipartite graph
- bipartite_iot = 0
- bipartite_web_server = 1
- if src_is_local:
- G.add_node(eth_src, Name=dev_list[eth_src], islocal=local_node, bipartite=bipartite_iot)
- src_node = eth_src
- else:
- hostname = None
- # Check first if the key (eth_dst) exists in the dictionary
- if eth_dst in device_dns_mappings:
- # If the source is not local, then it's inbound traffic, and hence the eth_dst is the MAC of the IoT device.
- hostname = device_dns_mappings[eth_dst].hostname_for_ip_at_time(ip_src, timestamp)
- if hostname is None:
- # Use IP if no hostname mapping
- hostname = ip_src
- # Non-smarthome devices can be merged later
- G.add_node(hostname, Merged='', islocal=remote_node, bipartite=bipartite_web_server)
- src_node = hostname
-
- if dst_is_local:
- G.add_node(eth_dst, Name=dev_list[eth_dst], islocal=local_node, bipartite=bipartite_iot)
- dst_node = eth_dst
- else:
- hostname = None
- # Check first if the key (eth_dst) exists in the dictionary
- if eth_src in device_dns_mappings:
- # If the destination is not local, then it's outbound traffic, and hence the eth_src is the MAC of the IoT device.
- hostname = device_dns_mappings[eth_src].hostname_for_ip_at_time(ip_dst, timestamp)
- if hostname is None:
- # Use IP if no hostname mapping
- hostname = ip_dst
- # Non-smarthome devices can be merged later
- G.add_node(hostname, Merged='', islocal=remote_node, bipartite=bipartite_web_server)
- dst_node = hostname
- G.add_edge(src_node, dst_node, Protocol=protocols_str, Volume=volume)
-
-
-def parse_json(file_path):
- """ Parse JSON file and create graph
- Args:
- file_path: path to the JSON file
- """
- # Create a smart home device list
- dev_list = create_device_list(DEVICE_MAC_LIST)
- # Create an exclusion list
- exc_list = create_device_list(EXCLUSION_MAC_LIST)
- # First parse the file once, constructing a map that contains information about individual devices' DNS resolutions.
- device_dns_mappings = parser.parse_dns.parse_json_dns(file_path)
- # Init empty graph
- G = nx.DiGraph()
- # Mapping from edge to a set of protocols
- edge_to_prot = dict()
- # Mapping from edge to traffic volume
- edge_to_vol = dict()
- # Parse file again, this time constructing a graph of device<->server and device<->device communication.
- i = 0
- with open(file_path) as jf:
- # Read JSON; data becomes reference to root JSON object (or in our case json array)
- data = json.load(jf)
- # Loop through json objects (packets) in data
- for p in data:
- # p is a JSON object, not an index - drill down to object containing data from the different layers
- layers = p[JSON_KEY_SOURCE][JSON_KEY_LAYERS]
-
- iscontinue = False
- for prot in listchkprot:
- if prot in layers:
- iscontinue = True
- if iscontinue:
- continue
-
- # Skip any non udp/non tcp traffic
- if JSON_KEY_UDP not in layers and JSON_KEY_TCP not in layers:
- continue
-
- # Fetch source and destination MACs
- eth = layers.get(JSON_KEY_ETH, None)
- if eth is None:
- print "[ WARNING: eth data not found ]"
- continue
- eth_src = eth.get(JSON_KEY_ETH_SRC, None)
- eth_dst = eth.get(JSON_KEY_ETH_DST, None)
- # Exclude devices in the exclusion list
- if eth_src in exc_list:
- print "[ WARNING: Source ", eth_src, " is excluded from graph! ]"
- continue
- if eth_dst in exc_list:
- print "[ WARNING: Destination ", eth_dst, " is excluded from graph! ]"
- continue
- # Exclude if IP does not exist in layers - this means IPv6
- if JSON_KEY_IP not in layers and JSON_KEY_IPV6 in layers:
- continue
-
- # Place nodes and edges in graph
- place_in_graph(G, eth_src, eth_dst, device_dns_mappings, dev_list, layers,
- edge_to_prot, edge_to_vol)
-
- # Print DNS mapping for reference
- #for mac in device_dns_mappings:
- # ddm = device_dns_mappings[mac]
- # ddm.print_mappings()
-
- return G
-
-
-# ------------------------------------------------------
-# Not currently used.
-# Might be useful later on if we wish to resolve IPs.
-def get_domain(host):
- ext_result = tldextract.extract(str(host))
- # Be consistent with ReCon and keep suffix
- domain = ext_result.domain + "." + ext_result.suffix
- return domain
-
-def is_IP(addr):
- try:
- socket.inet_aton(addr)
- return True
- except socket.error:
- return False
-# ------------------------------------------------------
-
-
-if __name__ == '__main__':
- if len(sys.argv) < 3:
- print "Usage:", sys.argv[0], "input_file output_file"
- print "outfile_file should end in .gexf"
- sys.exit(0)
- # Input file: Path to JSON file generated from tshark JSON output using Anastasia's script (extract_from_tshark.py).
- input_file = sys.argv[1]
- print "[ input_file =", input_file, "]"
- # Output file: Path to file where the Gephi XML should be written.
- output_file = sys.argv[2]
- print "[ output_file =", output_file, "]"
- # Construct graph from JSON
- G = parse_json(input_file)
- # Contract nodes that have the same properties, i.e. same protocols
- G = traverse_and_merge_nodes(G, DEVICE_MAC_LIST)
- # Write Graph in Graph Exchange XML format
- nx.write_gexf(G, output_file)