#!/usr/bin/env python3 # -*- coding: utf-8 -*- """ file: ndpi_example.py This file is part of nDPI. Copyright (C) 2011-19 - ntop.org Copyright (C) 2019 - Zied Aouini (Incremental improvements) nDPI is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. nDPI is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with nDPI. If not, see . """ from ndpi_typestruct import * from ctypes import * from scapy.all import * import sys # ------- return type & pcapstruct to declare ------- class WorkFlow(Structure): _fields_ = [("src_ip", c_uint32), ("dst_ip", c_uint32), ("src_port", c_uint16), ("dst_port", c_uint16), ("protocol", c_uint8), ("packets", c_uint32), ("detected_protocol", NDPIProtocol), ("detection_completed", c_uint8), ("id", c_uint32), ("src_id", POINTER(NDPIIdStruct)), ("dst_id", POINTER(NDPIIdStruct)), ("flow", POINTER(NDPIFlowStruct))] CMCFUN = CFUNCTYPE(c_int, c_void_p, c_void_p) GUESS = CFUNCTYPE(None, c_void_p, c_int32, c_int, c_void_p) FREE = CFUNCTYPE(None, c_void_p) def node_proto_guess_walker(nodo, which, depth, user_data): global ndpi_info_mod flow = cast(nodo, POINTER(POINTER(WorkFlow))).contents.contents if which == 0 or which == 3: # execute only preorder operation of the tree if flow.detection_completed == 0: # order for tree operation flow.detected_protocol = ndpi.ndpi_detection_giveup(ndpi_info_mod, flow.flow, 1, cast(addressof(c_uint8(0)), POINTER(c_uint8))) count_protocol[flow.detected_protocol.app_protocol] += flow.packets def py_cmp_fun(a, b): fa = cast(a, POINTER(WorkFlow)) fb = cast(b, POINTER(WorkFlow)) if fa.contents.src_ip < fb.contents.src_ip: return -1 elif fa.contents.src_ip > fb.contents.src_ip: return 1 if fa.contents.src_port < fb.contents.src_port: return -1 elif fa.contents.src_port > fb.contents.src_port: return 1 if fa.contents.dst_ip < fb.contents.dst_ip: return -1 elif fa.contents.dst_ip > fb.contents.dst_ip: return 1 if fa.contents.dst_port < fb.contents.dst_port: return -1 elif fa.contents.dst_port > fb.contents.dst_port: return 1 if fa.contents.protocol < fb.contents.protocol: return -1 elif fa.contents.protocol > fb.contents.protocol: return 1 return 0 def freer(a): pass cmp_func = CMCFUN(py_cmp_fun) guess_walker = GUESS(node_proto_guess_walker) free_walk = FREE(freer) # -------------------------------------- # number of analyzed packet packet_number = 0 flow_count = 0 max_num_udp_dissected_pkts = 16 max_num_tcp_dissected_pkts = 10 flows_root = c_void_p(None) flows_root_ref = pointer(flows_root) count_protocol = (c_int32 * (ndpi.ndpi_wrap_ndpi_max_supported_protocols() + ndpi.ndpi_wrap_ndpi_max_num_custom_protocols() + 1))() lista = [] # used to avoid impropriate memory deallocation from python # check ndpi version if ndpi.ndpi_get_api_version() != ndpi.ndpi_wrap_get_api_version(): print("nDPI Library version mismatch: please make sure this code and the nDPI library are in sync\n") sys.exit(-1) # create data structure of ndpi ndpi_info_mod = ndpi.ndpi_init_detection_module() if ndpi_info_mod is None: sys.exit(-1) else: ndpi_ndpi_finalize_initalization(ndpi_info_mod) def ip2int(ip): """ Convert an IP string to long and then c_uint32 """ packedIP = socket.inet_aton(ip) return int(struct.unpack("!I", packedIP)[0]) def get_flow(pkt): global flows_root global flows_root_ref global flow_count ip_packet = pkt[1] ip_protocol = ip_packet.proto transport_packet = None if ip_protocol == 6 or ip_protocol == 17: transport_packet = pkt[2] if transport_packet is not None: # to avoid two nodes in one binary tree for a flow ip_src = ip2int(ip_packet.src) ip_dst = ip2int(ip_packet.dst) src_port = transport_packet.sport dst_port = transport_packet.dport else: return None # set flows to correct type and data ndpi_flow = pointer(NDPIFlowStruct()) memset(ndpi_flow, 0, sizeof(NDPIFlowStruct)) if ip_src > ip_dst: flow = WorkFlow(ip_src, ip_dst, src_port, dst_port, int(ip_packet.proto), 0, NDPIProtocol(), 0, 0, pointer(NDPIIdStruct()), pointer(NDPIIdStruct()), ndpi_flow) else: flow = WorkFlow(ip_dst, ip_src, dst_port, src_port, int(ip_packet.proto), 0, NDPIProtocol(), 0, 0, pointer(NDPIIdStruct()), pointer(NDPIIdStruct()), ndpi_flow) flow_ref = pointer(flow) res = ndpi.ndpi_tfind(flow_ref, flows_root_ref, cmp_func) if res is None: ndpi.ndpi_tsearch(flow_ref, pointer(flows_root), cmp_func) # add lista.append(flow) flow_count += 1 return pointer(flow) flow = cast(res, POINTER(POINTER(WorkFlow))).contents return flow def packetcaptured(pkt): global packet_number global ndpi_info_mod flow = None h = PcapPktHdr() # getting flow try: flow = get_flow(pkt) except AttributeError: pass # ignore packet if flow is None: return # filling pcap_pkthdr h.len = h.caplen = len(pkt) h.ts.tv_sec = int(pkt["IP"].time/1000000) h.ts.tv_usec = int(pkt["IP"].time) # real work if int(pkt[1].frag) == 0: # not fragmented packet flow.contents.packets += 1 packet_number += 1 # get ndpi_iphdr address iphdr_addr = cast(c_char_p(pkt[1].build()), c_void_p) ndpi_flow = flow.contents.flow if flow.contents.detection_completed is 0: flow.contents.detected_protocol = ndpi.ndpi_detection_process_packet(ndpi_info_mod, ndpi_flow, cast(iphdr_addr, POINTER(c_uint8)), int(pkt[1].len), h.ts.tv_usec, flow.contents.src_id, flow.contents.dst_id) flow1 = flow.contents.detected_protocol valid = False if flow.contents.protocol == 6: valid = flow.contents.packets > max_num_tcp_dissected_pkts elif flow.contents.protocol == 17: valid = flow.contents.packets > max_num_udp_dissected_pkts # should we continue anylizing packet or not? if valid or flow1.app_protocol is not 0: if valid or flow1.master_protocol is not 91: # or # 91 is NDPI_PROTOCOL_TLS flow.contents.detection_completed = 1 # protocol found if flow1.app_protocol is 0: flow.contents.detected_protocol = ndpi.ndpi_detection_giveup(ndpi_info_mod, ndpi_flow, 1, cast(addressof(c_uint8(0)), POINTER(c_uint8))) def result(): global flows_root_ref global ndpi_info_mod print('\nnumber of analyzed packet: ' + str(packet_number)) print('number of flows: ' + str(flow_count)) ndpi.ndpi_twalk(flows_root_ref.contents, guess_walker, None) print('\nDetected protocols:') for i in range(0, ndpi.ndpi_get_num_supported_protocols(ndpi_info_mod)): if count_protocol[i] > 0: print("{}: {} packets".format( cast(ndpi.ndpi_get_proto_name(ndpi_info_mod, i), c_char_p).value.decode('utf-8'), str(count_protocol[i]))) def free(ndpi_struct): ndpi.ndpi_tdestroy(flows_root, free_walk) ndpi.ndpi_exit_detection_module(ndpi_struct) def initialize(ndpi_struct): all = NDPIProtocolBitMask() ndpi.ndpi_wrap_NDPI_BITMASK_SET_ALL(pointer(all)) ndpi.ndpi_set_protocol_detection_bitmask2(ndpi_struct, pointer(all)) print('Using nDPI ' + cast(ndpi.ndpi_revision(), c_char_p).value.decode("utf-8")) initialize(ndpi_info_mod) if len(sys.argv) != 2: print("\nUsage: ndpi_example.py ") sys.exit(0) if "." in sys.argv[1]: print('Reading pcap from file ' + sys.argv[1] + '...') scapy_cap = None try: scapy_cap = rdpcap(sys.argv[1]) except FileNotFoundError: print("\nFile not found") except Scapy_Exception: print("\nBad pcap") else: for packet in scapy_cap: packetcaptured(packet) else: print('Capturing live traffic from device ' + sys.argv[1] + '...') try: sniff(iface=sys.argv[1], prn=packetcaptured) except KeyboardInterrupt: print('\nInterrupted\n') except PermissionError: sys.exit('\nRoot privilege required for live capture on interface: {}\n'.format(sys.argv[1])) result() free(ndpi_info_mod)