2024-06-11 16:37:57 +09:00

77 lines
3.3 KiB
Python

from __future__ import annotations
from collections import defaultdict, deque, Counter
from enum import Enum
from typing import TYPE_CHECKING
from config import Config
from environment import Environment, Time
from sphinx import SphinxPacket
if TYPE_CHECKING:
from node import Node
class Adversary:
def __init__(self, env: Environment, config: Config):
self.env = env
self.config = config
self.message_sizes = []
self.senders_around_interval = Counter()
self.msg_pools_per_time = [] # list[dict[receiver, deque[time_received])]]
self.msg_pools_per_time.append(defaultdict(lambda: deque()))
self.msgs_received_per_time = [] # list[dict[receiver, dict[sender, list[time_sent]]]]
self.msgs_received_per_time.append(defaultdict(lambda: defaultdict(list)))
# dict[receiver, dict[time, list[(sender, time_sent, origin_id)]]]
self.final_msgs_received = defaultdict(lambda: defaultdict(list))
# self.node_states = defaultdict(dict)
self.env.process(self.update_observation_time())
def inspect_message_size(self, msg: SphinxPacket | bytes):
self.message_sizes.append(len(msg))
def observe_receiving_node(self, sender: "Node", receiver: "Node", time_sent: Time):
self.msg_pools_per_time[-1][receiver].append(self.env.now())
self.msgs_received_per_time[-1][receiver][sender].append(time_sent)
# if node not in self.node_states[self.env.now]:
# self.node_states[self.env.now][node] = NodeState.RECEIVING
def observe_sending_node(self, sender: "Node"):
msg_pool = self.msg_pools_per_time[-1][sender]
if len(msg_pool) > 0:
# Adversary doesn't know which message in the pool is being emitted. So, pop the oldest one from the pool.
msg_pool.popleft()
if self.is_around_message_interval(self.env.now()):
self.senders_around_interval.update({sender})
# self.node_states[self.env.now][node] = NodeState.SENDING
def observe_if_final_msg(self, sender: "Node", receiver: "Node", time_sent: Time, msg: SphinxPacket | bytes):
origin_id = receiver.inspect_message(msg)
if origin_id is not None:
cur_time = len(self.msgs_received_per_time) - 1
self.final_msgs_received[receiver][cur_time].append((sender, time_sent, origin_id))
def is_around_message_interval(self, time: Time) -> bool:
return time % self.config.mixnet.message_interval <= self.config.mixnet.max_message_prep_time
def update_observation_time(self):
while True:
yield self.env.timeout(1)
self.msgs_received_per_time.append(defaultdict(lambda: defaultdict(list)))
new_msg_pool = defaultdict(lambda: deque())
for receiver, msg_queue in self.msg_pools_per_time[-1].items():
for time_received in msg_queue:
# If the message is likely to be still pending and be emitted soon,
# pass it on to the next time slot.
if self.env.now() - time_received < self.config.mixnet.max_mix_delay:
new_msg_pool[receiver][0].append(time_received)
self.msg_pools_per_time.append(new_msg_pool)
class NodeState(Enum):
SENDING = 0
RECEIVING = 1