from lea import Lea from random import randrange from Attack.MembersMgmtCommAttack import MessageType from Attack.MembersMgmtCommAttack import Message # needed because of machine inprecision. E.g A time difference of 0.1s is stored as >0.1s EPS_TOLERANCE = 1e-13 # works for a difference of 0.1, no less def greater_than(a: float, b: float): """ A greater than operator desgined to handle slight machine inprecision up to EPS_TOLERANCE. :return: True if a > b, otherwise False """ return b - a < -EPS_TOLERANCE class CommunicationProcessor(): """ Class to process parsed input CSV/XML data and retrieve a mapping or other information. """ def __init__(self, mtypes:dict, nat:bool): """ Creates an instance of CommunicationProcessor. :param packets: the list of abstract packets :param mtypes: a dict containing an int to EnumType mapping of MessageTypes :param nat: whether NAT is present in this network """ self.packets = [] self.mtypes = mtypes self.nat = nat def set_mapping(self, packets: list, mapped_ids: dict): """ Set the selected mapping for this communication processor. :param packets: all packets contained in the mapped time frame :param mapped_ids: the chosen IDs """ self.packets = packets self.local_init_ids = set(mapped_ids) def get_comm_interval(self, cpp_comm_proc, strategy: str, number_ids: int, max_int_time: int, start_idx: int, end_idx: int): """ Finds a communication interval with respect to the given strategy. The interval is maximum of the given seconds and has at least number_ids communicating initiators in it. :param cpp_comm_proc: An instance of the C++ communication processor that stores all the input messages and is responsible for retrieving the interval(s) :param strategy: The selection strategy (i.e. random, optimal, custom) :param number_ids: The number of initiator IDs that have to exist in the interval(s) :param max_int_time: The maximum time period of the interval :param start_idx: The message index the interval should start at (None if not specified) :param end_idx: The message index the interval should stop at (inclusive) (None if not specified) :return: A dict representing the communication interval. It contains the initiator IDs, the start index and end index of the respective interval. The respective keys are {IDs, Start, End}. If no interval is found, an empty dict is returned. """ if strategy == "random": # try finding not-empty interval 5 times for i in range(5): start_idx = randrange(0, cpp_comm_proc.get_message_count()) interval = cpp_comm_proc.find_interval_from_startidx(start_idx, number_ids, max_int_time) if interval and interval["IDs"]: return interval return {} elif strategy == "optimal": intervals = cpp_comm_proc.find_optimal_interval(number_ids, max_int_time) if not intervals: return {} else: for i in range(5): interval = intervals[randrange(0, len(intervals))] if interval and interval["IDs"]: return interval return {} elif strategy == "custom": if start_idx is None: print("Custom strategy was selected, but no (valid) start index was specified.") print("Because of this, a random interval is selected.") start_idx = randrange(0, cpp_comm_proc.get_message_count()) elif end_idx is not None: ids = cpp_comm_proc.get_interval_init_ids(start_idx, end_idx) if not ids: return {} return {"IDs": ids, "Start": start_idx, "End": end_idx} interval = cpp_comm_proc.find_interval_from_startidx(start_idx, number_ids, max_int_time) if not interval or not interval["IDs"]: return {} return interval def det_id_roles_and_msgs(self): """ Determine the role of every mapped ID. The role can be initiator, responder or both. On the side also connect corresponding messages together to quickly find out which reply belongs to which request and vice versa. :return: the selected messages """ mtypes = self.mtypes # setup initial variables and their values respnd_ids = set() # msgs --> the filtered messages, msg_id --> an increasing ID to give every message an artificial primary key msgs, msg_id = [], 0 # keep track of previous request to find connections prev_reqs = {} # used to determine whether a request has been seen yet, so that replies before the first request are skipped and do not throw an error by # accessing the empty dict prev_reqs (this is not a perfect solution, but it works most of the time) req_seen = False local_init_ids = self.local_init_ids external_init_ids = set() # process every packet individually for packet in self.packets: id_src, id_dst, msg_type, time = packet["Src"], packet["Dst"], int(packet["Type"]), float(packet["Time"]) lineno = packet.get("LineNumber", -1) # if if either one of the IDs is not mapped, continue if (id_src not in local_init_ids) and (id_dst not in local_init_ids): continue # convert message type number to enum type msg_type = mtypes[msg_type] # process a request if msg_type in {MessageType.SALITY_HELLO, MessageType.SALITY_NL_REQUEST}: if not self.nat and id_dst in local_init_ids and id_src not in local_init_ids: external_init_ids.add(id_src) elif id_src not in local_init_ids: continue else: # process ID's role respnd_ids.add(id_dst) # convert the abstract message into a message object to handle it better msg_str = "{0}-{1}".format(id_src, id_dst) msg = Message(msg_id, id_src, id_dst, msg_type, time, line_no = lineno) msgs.append(msg) prev_reqs[msg_str] = msg_id msg_id += 1 req_seen = True # process a reply elif msg_type in {MessageType.SALITY_HELLO_REPLY, MessageType.SALITY_NL_REPLY} and req_seen: if not self.nat and id_src in local_init_ids and id_dst not in local_init_ids: # process ID's role external_init_ids.add(id_dst) elif id_dst not in local_init_ids: continue else: # process ID's role respnd_ids.add(id_src) # convert the abstract message into a message object to handle it better msg_str = "{0}-{1}".format(id_dst, id_src) # find the request message ID for this response and set its reference index refer_idx = prev_reqs[msg_str] msgs[refer_idx].refer_msg_id = msg_id msg = Message(msg_id, id_src, id_dst, msg_type, time, refer_idx, lineno) msgs.append(msg) # remove the request to this response from storage del(prev_reqs[msg_str]) msg_id += 1 elif msg_type == MessageType.TIMEOUT and id_src in local_init_ids and not self.nat: # convert the abstract message into a message object to handle it better msg_str = "{0}-{1}".format(id_dst, id_src) # find the request message ID for this response and set its reference index refer_idx = prev_reqs.get(msg_str) if refer_idx is not None: msgs[refer_idx].refer_msg_id = msg_id if msgs[refer_idx].type == MessageType.SALITY_NL_REQUEST: msg = Message(msg_id, id_src, id_dst, MessageType.SALITY_NL_REPLY, time, refer_idx, lineno) else: msg = Message(msg_id, id_src, id_dst, MessageType.SALITY_HELLO_REPLY, time, refer_idx, lineno) msgs.append(msg) # remove the request to this response from storage del(prev_reqs[msg_str]) msg_id += 1 # store the retrieved information in this object for later use self.respnd_ids = sorted(respnd_ids) self.external_init_ids = sorted(external_init_ids) self.messages = msgs # return the selected messages return self.messages def det_ext_and_local_ids(self, prob_rspnd_local: int=0): """ Map the given IDs to a locality (i.e. local or external} considering the given probabilities. :param comm_type: the type of communication (i.e. local, external or mixed) :param prob_rspnd_local: the probabilty that a responder is local """ external_ids = set() local_ids = self.local_init_ids.copy() # set up probabilistic chooser rspnd_locality = Lea.fromValFreqsDict({"local": prob_rspnd_local*100, "external": (1-prob_rspnd_local)*100}) for id_ in self.external_init_ids: external_ids.add(id_) # determine responder localities for id_ in self.respnd_ids: if id_ in local_ids or id_ in external_ids: continue pos = rspnd_locality.random() if pos == "local": local_ids.add(id_) elif pos == "external": external_ids.add(id_) self.local_ids, self.external_ids = local_ids, external_ids return self.local_ids, self.external_ids