├── requirements.txt ├── Dockerfile ├── .travis.yml ├── crawler_file.py ├── README.md ├── app.py ├── crawler_mongo.py ├── .gitignore ├── crawler.py ├── utils.py ├── torrent.py ├── spyder.py └── LICENSE /requirements.txt: -------------------------------------------------------------------------------- 1 | py3-bencode==0.0.3 2 | aio-udp-server==0.0.2 3 | chardet==3.0.4 4 | motor==1.1 5 | pymongo==3.5.1 6 | -------------------------------------------------------------------------------- /Dockerfile: -------------------------------------------------------------------------------- 1 | FROM python:3.6.3-alpine3.7 2 | 3 | MAINTAINER Bashkirtsev D.A. 4 | LABEL maintainer="bashkirtsevich@gmail.com" 5 | 6 | WORKDIR /usr/src/app 7 | ENV CRAWLER_WRITER=file 8 | COPY . . 9 | RUN apk update && apk upgrade && \ 10 | apk add --no-cache git && \ 11 | pip install -r requirements.txt 12 | 13 | CMD [ "python", "app.py" ] 14 | -------------------------------------------------------------------------------- /.travis.yml: -------------------------------------------------------------------------------- 1 | sudo: required 2 | 3 | language: python 4 | 5 | services: 6 | - docker 7 | 8 | install: 9 | - echo "install nothing!" 10 | 11 | script: 12 | - echo "no tests!" 13 | 14 | after_success: 15 | - docker --version 16 | - docker build -t grapefruit-crawler . 17 | - docker tag grapefruit-crawler $DOCKER_USERNAME/grapefruit-crawler 18 | - docker login -u "$DOCKER_USERNAME" -p "$DOCKER_PASSWORD" 19 | - docker push bashkirtsevich/grapefruit-crawler:latest 20 | -------------------------------------------------------------------------------- /crawler_file.py: -------------------------------------------------------------------------------- 1 | import os 2 | from crawler import TorrentCrawler 3 | from utils import hexlify 4 | 5 | 6 | class TorrentCrawlerFile(TorrentCrawler): 7 | def __init__(self, folder_path, **kwargs): 8 | super().__init__(**kwargs) 9 | 10 | self.folder_path = folder_path 11 | 12 | def get_path_for_torrent(self, info_hash): 13 | return os.path.join(self.folder_path, hexlify(info_hash) + ".torrent") 14 | 15 | async def enqueue_torrent(self, info_hash): 16 | if not os.path.exists(self.get_path_for_torrent(info_hash)): 17 | await super(TorrentCrawlerFile, self).enqueue_torrent(info_hash) 18 | 19 | async def save_torrent_metadata(self, info_hash, metadata): 20 | with open(self.get_path_for_torrent(info_hash), "wb") as file: 21 | file.write(metadata) 22 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # Grapefruit-crawler 2 | [![Codacy Badge](https://api.codacy.com/project/badge/Grade/fcd09fccacfd45a7a3590c64d9ea95aa)](https://www.codacy.com/app/bashkirtsevich/grapefruit-crawler?utm_source=github.com&utm_medium=referral&utm_content=bashkirtsevich-llc/grapefruit-crawler&utm_campaign=Badge_Grade) 3 | [![Build Status](https://travis-ci.org/bashkirtsevich-llc/grapefruit-crawler.svg?branch=master)](https://travis-ci.org/bashkirtsevich-llc/grapefruit-crawler) 4 | 5 | Grapefruit torrent-network sniffer. 6 | 7 | ## Requirements 8 | * Python 3.6.3 or higher 9 | * MongoDB 3.2.17 or higher 10 | 11 | ## Execution 12 | 1. Install requirements 13 | ```bash 14 | pip install -r requirements.txt 15 | ``` 16 | 2. Set environment variables 17 | ``` 18 | MONGODB_URL=mongodb://mongodb:27017/grapefruit 19 | ``` 20 | Optional (default = `grapefruit`): 21 | ``` 22 | MONGODB_BASE_NAME=grapefruit 23 | ``` 24 | 3. Start crawler 25 | ```bash 26 | python app.py 27 | ``` 28 | -------------------------------------------------------------------------------- /app.py: -------------------------------------------------------------------------------- 1 | import os 2 | 3 | 4 | def run_server(server_factory): 5 | initial_nodes = [ 6 | ("67.215.246.10", 6881), # router.bittorrent.com 7 | ("87.98.162.88", 6881), # dht.transmissionbt.com 8 | ("82.221.103.244", 6881) # router.utorrent.com 9 | ] 10 | 11 | socket_host = os.getenv("SOCKET_HOST", "0.0.0.0") 12 | socket_port = int(os.getenv("SOCKET_PORT", "6881")) 13 | 14 | miner_interval = float(os.getenv("MINER_INTERVAL", "0.1")) 15 | download_bandwidth = int(os.getenv("DOWNLOAD_BANDWIDTH", "0")) 16 | upload_bandwidth = int(os.getenv("UPLOAD_BANDWIDTH", "0")) 17 | 18 | server = server_factory( 19 | bootstrap_nodes=initial_nodes, 20 | miner_interval=miner_interval, 21 | download_speed=download_bandwidth, 22 | upload_speed=upload_bandwidth 23 | ) 24 | server.run( 25 | host=socket_host, 26 | port=socket_port 27 | ) 28 | 29 | 30 | if __name__ == '__main__': 31 | crawler_name = os.getenv("CRAWLER_WRITER", "file") 32 | 33 | if crawler_name == "file": 34 | from crawler_file import TorrentCrawlerFile 35 | 36 | run_server( 37 | lambda **kwargs: TorrentCrawlerFile( 38 | folder_path=os.getenv("TORRENTS_FOLDER"), 39 | **kwargs 40 | ) 41 | ) 42 | 43 | elif crawler_name == "mongo": 44 | from crawler_mongo import TorrentCrawlerMongo 45 | 46 | run_server( 47 | lambda **kwargs: TorrentCrawlerMongo( 48 | db_url=os.getenv("MONGO_URI"), 49 | db_name=os.getenv("MONGO_DB_NAME"), 50 | **kwargs 51 | ) 52 | ) 53 | 54 | else: 55 | print("Wrong 'CRAWLER_WRITER' value") 56 | -------------------------------------------------------------------------------- /crawler_mongo.py: -------------------------------------------------------------------------------- 1 | from datetime import datetime 2 | 3 | import motor.motor_asyncio 4 | from pymongo import ASCENDING 5 | 6 | from crawler import TorrentCrawler 7 | from utils import hexlify, decode_bytes 8 | from bencode import bdecode 9 | from utils import decode_bkeys 10 | 11 | 12 | class TorrentCrawlerMongo(TorrentCrawler): 13 | def __init__(self, db_url, db_name, **kwargs): 14 | super().__init__(**kwargs) 15 | 16 | client = motor.motor_asyncio.AsyncIOMotorClient(db_url) 17 | self.db = client[db_name] 18 | self.loop.run_until_complete(self.create_index()) 19 | 20 | async def create_index(self): 21 | index = { 22 | "name": "info_hash", 23 | "keys": [("info_hash", ASCENDING)], 24 | "unique": True 25 | } 26 | 27 | coll = self.db.torrents 28 | if index["name"] not in await coll.index_information(): 29 | await coll.create_index(**index) 30 | 31 | async def enqueue_torrent(self, info_hash): 32 | if await self.db.torrents.count(filter={"info_hash": hexlify(info_hash)}) == 0: 33 | await super(TorrentCrawlerMongo, self).enqueue_torrent(info_hash) 34 | 35 | async def save_torrent_metadata(self, info_hash, metadata): 36 | torrent = bdecode(metadata, decoder=decode_bkeys) 37 | 38 | if "files" in torrent: 39 | files = torrent["files"] 40 | else: 41 | files = [{"length": torrent["length"], "path": [torrent["name"]]}] 42 | 43 | item = { 44 | "info_hash": hexlify(info_hash), 45 | "files": decode_bytes(files), 46 | "name": decode_bytes(torrent["name"]), 47 | "timestamp": datetime.now() 48 | } 49 | 50 | await self.db.torrents.insert_one(item) 51 | -------------------------------------------------------------------------------- /.gitignore: -------------------------------------------------------------------------------- 1 | # Byte-compiled / optimized / DLL files 2 | __pycache__/ 3 | *.py[cod] 4 | *$py.class 5 | 6 | # C extensions 7 | *.so 8 | 9 | # Distribution / packaging 10 | .Python 11 | env/ 12 | build/ 13 | develop-eggs/ 14 | dist/ 15 | downloads/ 16 | eggs/ 17 | .eggs/ 18 | lib/ 19 | lib64/ 20 | parts/ 21 | sdist/ 22 | var/ 23 | wheels/ 24 | *.egg-info/ 25 | .installed.cfg 26 | *.egg 27 | 28 | # PyInstaller 29 | # Usually these files are written by a python script from a template 30 | # before PyInstaller builds the exe, so as to inject date/other infos into it. 31 | *.manifest 32 | *.spec 33 | 34 | # Installer logs 35 | pip-log.txt 36 | pip-delete-this-directory.txt 37 | 38 | # Unit test / coverage reports 39 | htmlcov/ 40 | .tox/ 41 | .coverage 42 | .coverage.* 43 | .cache 44 | nosetests.xml 45 | coverage.xml 46 | *.cover 47 | .hypothesis/ 48 | 49 | # Translations 50 | *.mo 51 | *.pot 52 | 53 | # Django stuff: 54 | *.log 55 | local_settings.py 56 | 57 | # Flask stuff: 58 | instance/ 59 | .webassets-cache 60 | 61 | # Scrapy stuff: 62 | .scrapy 63 | 64 | # Sphinx documentation 65 | docs/_build/ 66 | 67 | # PyBuilder 68 | target/ 69 | 70 | # Jupyter Notebook 71 | .ipynb_checkpoints 72 | 73 | # pyenv 74 | .python-version 75 | 76 | # celery beat schedule file 77 | celerybeat-schedule 78 | 79 | # SageMath parsed files 80 | *.sage.py 81 | 82 | # dotenv 83 | .env 84 | 85 | # virtualenv 86 | .venv 87 | venv/ 88 | ENV/ 89 | 90 | # Spyder project settings 91 | .spyderproject 92 | .spyproject 93 | 94 | # Rope project settings 95 | .ropeproject 96 | 97 | # mkdocs documentation 98 | /site 99 | 100 | # mypy 101 | .mypy_cache/ 102 | 103 | #idea 104 | .idea/ 105 | 106 | # Local spp settings 107 | local.py -------------------------------------------------------------------------------- /crawler.py: -------------------------------------------------------------------------------- 1 | import asyncio 2 | 3 | from spyder import DHTSpyder 4 | from torrent import BitTorrentProtocol 5 | 6 | 7 | class TorrentCrawler(DHTSpyder): 8 | def __init__(self, **kwargs): 9 | super().__init__(**kwargs) 10 | 11 | self.torrent_in_progress = set() # For prevent multiple search same torrents 12 | 13 | async def create_connection(self, host, port, info_hash, result_future): 14 | return await self.loop.create_connection( 15 | lambda: BitTorrentProtocol(info_hash, result_future), 16 | host=host, port=port 17 | ) 18 | 19 | async def connect_to_peer(self, peer, info_hash): 20 | try: 21 | result_future = self.loop.create_future() 22 | await self.create_connection(peer.host, peer.port, info_hash, result_future) 23 | return await result_future 24 | except: 25 | return None 26 | 27 | async def wait_for_torrent(self, info_hash, peers): 28 | # Wait for 1 minute for torrent completion 29 | done, pending = await asyncio.wait([ 30 | self.connect_to_peer(peer, info_hash) 31 | for peer in peers 32 | ], timeout=60.0, return_when=asyncio.FIRST_COMPLETED, loop=self.loop) 33 | 34 | for task in pending: 35 | task.cancel() 36 | 37 | return await done.pop() if done else None 38 | 39 | async def connect_with_peers(self, info_hash, peers): 40 | for i in range(0, len(peers), 20): 41 | try: 42 | metadata = await self.wait_for_torrent(info_hash, peers[i: i + 20]) 43 | except: 44 | continue 45 | else: 46 | if metadata: 47 | asyncio.ensure_future(self.save_torrent_metadata(info_hash, metadata), loop=self.loop) 48 | break 49 | 50 | if info_hash in self.torrent_in_progress: 51 | self.torrent_in_progress.remove(info_hash) 52 | 53 | async def enqueue_torrent(self, info_hash): 54 | if info_hash not in self.torrent_in_progress: 55 | self.torrent_in_progress.add(info_hash) 56 | self.search_peers(info_hash) 57 | 58 | async def get_peers_received(self, node_id, info_hash, addr): 59 | await self.enqueue_torrent(info_hash) 60 | 61 | async def announce_peer_received(self, node_id, info_hash, port, addr): 62 | await self.enqueue_torrent(info_hash) 63 | 64 | async def peers_values_received(self, info_hash, peers): 65 | await self.connect_with_peers(info_hash, list(peers)) 66 | 67 | async def save_torrent_metadata(self, info_hash, metadata): 68 | pass 69 | -------------------------------------------------------------------------------- /utils.py: -------------------------------------------------------------------------------- 1 | import binascii 2 | import math 3 | from collections import namedtuple 4 | from heapq import nsmallest 5 | from secrets import token_bytes, randbits 6 | from socket import inet_ntoa, inet_aton 7 | 8 | from chardet import detect 9 | 10 | Peer = namedtuple("peer", ["host", "port"]) 11 | Node = namedtuple("node", ["id", "host", "port"]) 12 | 13 | 14 | def generate_id(): 15 | return token_bytes(2) 16 | 17 | 18 | def generate_node_id(): 19 | return token_bytes(20) 20 | 21 | 22 | def xor(node_one_id, node_two_id): 23 | return int.from_bytes(node_one_id, "big") ^ int.from_bytes(node_two_id, "big") 24 | 25 | 26 | def fetch_k_closest_nodes(nodes, target_id, k_value=8): 27 | return nsmallest(k_value, nodes, lambda node: xor(node.id, target_id)) 28 | 29 | 30 | def get_rand_bool(): 31 | return bool(randbits(1)) 32 | 33 | 34 | def get_routing_table_index(distance): 35 | if distance: 36 | return int(math.floor(math.log(math.fabs(distance), 2.0))) 37 | else: 38 | return 0 39 | 40 | 41 | def decode_values(values): 42 | for value in values: 43 | if len(value) % 6 != 0: 44 | return 45 | 46 | ip = inet_ntoa(value[0: 4]) # from network order to IP address 47 | port = int.from_bytes(value[4: 6], "big") 48 | 49 | if port >= 1024: 50 | yield Peer(ip, port) 51 | 52 | 53 | def decode_nodes(nodes): 54 | if len(nodes) % 26 != 0: 55 | return 56 | 57 | for i in range(0, len(nodes), 26): 58 | node_id = nodes[i: i + 20] 59 | 60 | ip = inet_ntoa(nodes[i + 20: i + 24]) # from network order to IP address 61 | port = int.from_bytes(nodes[i + 24: i + 26], "big") 62 | 63 | if port >= 1024: 64 | yield Node(node_id, ip, port) 65 | 66 | 67 | def encode_nodes(nodes): 68 | result = bytes() 69 | 70 | for node_id, ip, port in nodes: 71 | ip_message = inet_aton(ip) 72 | port_message = port.to_bytes(2, "big") 73 | 74 | result = result + node_id + ip_message + port_message 75 | 76 | return result 77 | 78 | 79 | def hexlify(info_hash): 80 | return str(binascii.hexlify(info_hash), "utf-8") 81 | 82 | 83 | def decode_bytes(byte_str): 84 | if isinstance(byte_str, list): 85 | return [decode_bytes(item) for item in byte_str] 86 | if isinstance(byte_str, dict): 87 | return {key: decode_bytes(value) for key, value in byte_str.items()} 88 | if isinstance(byte_str, bytes): 89 | return str(byte_str, detect(byte_str).get("encoding", "utf-8")) 90 | return byte_str 91 | 92 | 93 | def decode_bkeys(val_type, value): 94 | return str(value, "utf-8") if val_type == "key" else value 95 | -------------------------------------------------------------------------------- /torrent.py: -------------------------------------------------------------------------------- 1 | import asyncio 2 | from hashlib import sha1 3 | 4 | from bencode import bencode, bdecode, decode_dict, bytes_decode_recursive 5 | from utils import decode_bkeys 6 | 7 | 8 | class BitTorrentProtocolException(Exception): 9 | pass 10 | 11 | 12 | class BitTorrentProtocol(asyncio.Protocol): 13 | def __init__(self, info_hash, result_future): 14 | self.info_hash = info_hash 15 | self.result_future = result_future 16 | self.transport = None 17 | self.buffer = bytes() 18 | self.need_handshake = True 19 | self.metadata = {} 20 | 21 | def connection_made(self, transport): 22 | self.transport = transport 23 | 24 | data = b"\x13BitTorrent protocol" 25 | data += b"\x00\x00\x00\x00\x00\x10\x00\x05" 26 | data += self.info_hash + b"-UT3230-!pT\xed\xb1\xfc\x80x\xa9\x0c\r\x94" 27 | self.transport.write(data) 28 | 29 | def connection_lost(self, exc): 30 | if self.transport: 31 | self.transport.close() 32 | 33 | def send_extended_message(self, message_id, message_data): 34 | buf = b"\x14" + message_id.to_bytes(1, "big") + bencode(message_data) 35 | self.transport.write(len(buf).to_bytes(4, "big") + buf) 36 | 37 | def handle_message(self, msg_data): 38 | if msg_data[0] == 0: 39 | hs_body = bdecode(msg_data[1:], decoder=decode_bkeys) 40 | 41 | metadata_size = hs_body.get("metadata_size", 0) 42 | ut_metadata_id = hs_body.get("m", {}).get("ut_metadata", 0) 43 | 44 | if metadata_size and ut_metadata_id: 45 | hs_response = { 46 | "e": 0, 47 | "metadata_size": metadata_size, 48 | "v": "μTorrent 3.2.3", 49 | "m": {"ut_metadata": 1}, 50 | "reqq": 255 51 | } 52 | 53 | self.send_extended_message(0, hs_response) 54 | 55 | for i in range(0, int(1 + metadata_size / (16 * 1024))): 56 | self.send_extended_message(ut_metadata_id, {"msg_type": 0, "piece": i}) 57 | 58 | elif msg_data[0] == 1: 59 | r, l = decode_dict(msg_data[1:], 0) 60 | 61 | r = bytes_decode_recursive(r, decoder=decode_bkeys) 62 | 63 | if r["msg_type"] == 1: 64 | self.metadata[r["piece"]] = msg_data[l + 1:] 65 | 66 | metadata = bytes() 67 | 68 | for key in sorted(self.metadata.keys()): 69 | metadata += self.metadata[key] 70 | 71 | if len(metadata) == r["total_size"]: 72 | self.transport.close() 73 | 74 | if sha1(metadata).digest() == self.info_hash: 75 | if not self.result_future.done(): 76 | self.result_future.set_result(metadata) 77 | else: 78 | raise BitTorrentProtocolException("info_hash != sha1(metadata)") 79 | 80 | def data_received(self, data): 81 | def parse_message(message): 82 | return (int.from_bytes(message[:1], "big"), message[1:]) if message else None 83 | 84 | self.buffer += data 85 | 86 | if self.need_handshake: 87 | if len(self.buffer) >= 68: 88 | self.buffer = self.buffer[68:] 89 | self.need_handshake = False 90 | else: 91 | while len(self.buffer) >= 4: 92 | msg_len = int.from_bytes(self.buffer[:4], "big") 93 | 94 | if len(self.buffer) >= msg_len + 4: 95 | message = parse_message(self.buffer[4: msg_len + 4]) 96 | if message and message[0] == 20: 97 | self.handle_message(message[1]) 98 | 99 | self.buffer = self.buffer[msg_len + 4:] 100 | else: 101 | break 102 | -------------------------------------------------------------------------------- /spyder.py: -------------------------------------------------------------------------------- 1 | import asyncio 2 | from aioudp import UDPServer 3 | from collections import namedtuple 4 | from datetime import datetime 5 | from random import SystemRandom 6 | 7 | from bencode import bencode, bdecode, BTFailure 8 | 9 | from utils import (generate_node_id, generate_id, get_routing_table_index, xor, decode_nodes, encode_nodes, 10 | get_rand_bool, fetch_k_closest_nodes, decode_values, Node, decode_bkeys) 11 | 12 | Searcher = namedtuple("searcher", ["info_hash", "nodes", "values", "attempts_count", "timestamp"]) 13 | 14 | 15 | class DHTSpyder(UDPServer): 16 | def __init__(self, bootstrap_nodes, node_id=None, miner_interval=0.001, **kwargs): 17 | super(DHTSpyder, self).__init__(**kwargs) 18 | 19 | self.bootstrap_nodes = bootstrap_nodes 20 | self.node_id = node_id or generate_node_id() 21 | self.miner_interval = miner_interval 22 | 23 | self.routing_table = [set() for _ in range(160)] 24 | self.candidates = set() 25 | 26 | self.searchers = {} 27 | self.searchers_seq = 0 28 | 29 | self.random = SystemRandom() 30 | 31 | def connection_made(self): 32 | # Bootstrap 33 | for node in self.bootstrap_nodes: 34 | self.find_node(node, self.node_id) 35 | 36 | # Start miner 37 | asyncio.ensure_future(self._dig_periodically(), loop=self.loop) 38 | asyncio.ensure_future(self._update_searchers_periodically(), loop=self.loop) 39 | 40 | async def datagram_received(self, data, addr): 41 | try: 42 | msg = bdecode(data, decoder=decode_bkeys) 43 | except BTFailure: 44 | # TODO: Log error 45 | pass 46 | else: 47 | self.handle_message(msg, addr) 48 | 49 | def _fetch_random_candidates(self, k): 50 | result = self.random.sample(self.candidates, k) 51 | 52 | for item in result: 53 | self.candidates.remove(item) 54 | 55 | return result 56 | 57 | def _new_event(self, handler): 58 | asyncio.ensure_future(handler, loop=self.loop) 59 | 60 | async def _dig_periodically(self): 61 | while True: 62 | target_id = generate_node_id() 63 | 64 | nodes = [ 65 | *self.get_closest_nodes(target_id), 66 | *self._fetch_random_candidates(min(len(self.candidates), 7)) 67 | ] 68 | 69 | for _, host, port in nodes: 70 | self.find_node((host, port), target_id) 71 | 72 | await asyncio.sleep(self.miner_interval) 73 | 74 | async def _update_searchers_periodically(self): 75 | while True: 76 | now = datetime.now() 77 | for t, item in self.searchers.copy().items(): 78 | if (now - item.timestamp).seconds >= 120: 79 | if item.values: 80 | self._new_event(self.peers_values_received(item.info_hash, item.values)) 81 | 82 | self.searchers.pop(t) 83 | 84 | await asyncio.sleep(1) 85 | 86 | def send_message(self, data, addr): 87 | self.send(bencode(data), addr) 88 | 89 | def find_node(self, addr, target=None): 90 | self.send_message({ 91 | "t": generate_id(), 92 | "y": "q", 93 | "q": "find_node", 94 | "a": { 95 | "id": generate_node_id(), 96 | "target": target or generate_node_id() 97 | } 98 | }, addr) 99 | 100 | def get_peers(self, addr, info_hash, t=None): 101 | self.send_message({ 102 | "t": t or generate_id(), 103 | "y": "q", 104 | "q": "get_peers", 105 | "a": { 106 | "id": generate_node_id(), 107 | "info_hash": info_hash 108 | } 109 | }, addr) 110 | 111 | def get_closest_nodes(self, target_id, k_value=8): 112 | closest_l = set() 113 | closest_r = set() 114 | 115 | r_table_idx = get_routing_table_index(xor(self.node_id, target_id)) 116 | 117 | idx = r_table_idx 118 | while idx >= 0 and len(closest_l) < k_value: 119 | closest_l |= set(fetch_k_closest_nodes(self.routing_table[idx], target_id, k_value)) 120 | idx -= 1 121 | 122 | idx = r_table_idx + 1 123 | while idx < 160 and len(closest_r) < k_value: 124 | closest_r |= set(fetch_k_closest_nodes(self.routing_table[idx], target_id, k_value)) 125 | idx += 1 126 | 127 | return fetch_k_closest_nodes(closest_l | closest_r, target_id, k_value) 128 | 129 | def add_node(self, node): 130 | r_table_index = get_routing_table_index(xor(node.id, self.node_id)) 131 | rt = self.routing_table[r_table_index] 132 | 133 | if len(rt) < 1600: 134 | rt.add(node) 135 | elif get_rand_bool() and node not in rt: 136 | rt.remove(self.random.sample(rt, 1)[0]) 137 | else: 138 | self.find_node((node.host, node.port)) 139 | 140 | def search_peers(self, info_hash): 141 | if self.searchers_seq >= 2 ** 32 - 1: 142 | self.searchers_seq = 0 143 | else: 144 | self.searchers_seq += 1 145 | 146 | t = self.searchers_seq.to_bytes(4, "big") 147 | self.searchers[t] = Searcher(info_hash, set(), set(), 8, datetime.now()) 148 | 149 | for node in self.get_closest_nodes(info_hash, 16): 150 | self.get_peers((node.host, node.port), info_hash, t) 151 | 152 | def update_peers_searcher(self, t, nodes, values): 153 | info_hash, old_nodes, old_values, attempts_count, timestamp = self.searchers.pop(t) 154 | 155 | # "nodes" and "values" must be instance of "set" type 156 | new_nodes = old_nodes | nodes 157 | new_values = old_values | values 158 | 159 | # If new_closest contains same data as old_closest, we decrease attempt counter 160 | new_closest, old_closest = (set(fetch_k_closest_nodes(n, info_hash, 16)) for n in (new_nodes, old_nodes)) 161 | if new_closest == old_closest: 162 | attempts_count -= 1 163 | 164 | if attempts_count > 0: 165 | self.searchers[t] = Searcher(info_hash, new_nodes, new_values, attempts_count, timestamp) 166 | 167 | for node in new_closest: 168 | self.get_peers((node.host, node.port), info_hash, t) 169 | elif new_values: 170 | self._new_event(self.peers_values_received(info_hash, new_values)) 171 | 172 | def handle_message(self, msg, addr): 173 | try: 174 | msg_type = str(msg.get("y", b""), "utf-8") 175 | 176 | if msg_type == "r": 177 | self.handle_response(msg, addr) 178 | elif msg_type == "q": 179 | self.handle_query(msg, addr) 180 | except: 181 | self.send_message({ 182 | "y": "e", 183 | "e": [202, "Server Error"], 184 | "t": msg.get("t", "") 185 | }, addr) 186 | 187 | raise 188 | 189 | def handle_response(self, msg, addr): 190 | args = msg["r"] 191 | t = msg["t"] 192 | node_id = args["id"] 193 | 194 | nodes = set(decode_nodes(args.get("nodes", b""))) 195 | values = set(decode_values(args.get("values", []))) 196 | 197 | if t in self.searchers: 198 | self.update_peers_searcher(t, nodes, values) 199 | else: 200 | new_candidates = self.random.sample(nodes, min(len(nodes), 8)) 201 | 202 | if len(self.candidates) > 160000: 203 | self._fetch_random_candidates(len(self.candidates) - 160000) 204 | 205 | self.candidates.update(new_candidates) 206 | 207 | self.add_node(Node(node_id, addr[0], addr[1])) 208 | 209 | def handle_query(self, msg, addr): 210 | args = msg["a"] 211 | node_id = args["id"] 212 | query_type = str(msg["q"], "utf-8") 213 | 214 | response_id = self.node_id 215 | 216 | if query_type == "ping": 217 | self.send_message({ 218 | "t": msg["t"], 219 | "y": "r", 220 | "r": { 221 | "id": response_id 222 | } 223 | }, addr) 224 | 225 | self._new_event(self.ping_received(node_id, addr)) 226 | 227 | elif query_type == "find_node": 228 | target_node_id = args["target"] 229 | 230 | self.send_message({ 231 | "t": msg["t"], 232 | "y": "r", 233 | "r": { 234 | "id": response_id, 235 | "nodes": encode_nodes(self.get_closest_nodes(target_node_id)) 236 | } 237 | }, addr) 238 | 239 | self._new_event(self.find_node_received(node_id, target_node_id, addr)) 240 | 241 | elif query_type == "get_peers": 242 | info_hash = args["info_hash"] 243 | token = generate_node_id() 244 | 245 | self.send_message({ 246 | "t": msg["t"], 247 | "y": "r", 248 | "r": { 249 | "id": response_id, 250 | "nodes": encode_nodes(self.get_closest_nodes(info_hash)), 251 | "token": token 252 | } 253 | }, addr) 254 | 255 | self._new_event(self.get_peers_received(node_id, info_hash, addr)) 256 | 257 | elif query_type == "announce_peer": 258 | info_hash = args["info_hash"] 259 | port = args.get("port", None) 260 | 261 | self.send_message({ 262 | "t": msg["t"], 263 | "y": "r", 264 | "r": { 265 | "id": response_id 266 | } 267 | }, addr) 268 | 269 | self._new_event(self.announce_peer_received(node_id, info_hash, port, addr)) 270 | 271 | self.add_node(Node(node_id, addr[0], addr[1])) 272 | 273 | async def ping_received(self, node_id, addr): 274 | pass 275 | 276 | async def find_node_received(self, node_id, target, addr): 277 | pass 278 | 279 | async def get_peers_received(self, node_id, info_hash, addr): 280 | pass 281 | 282 | async def announce_peer_received(self, node_id, info_hash, port, addr): 283 | pass 284 | 285 | async def peers_values_received(self, info_hash, peers): 286 | pass 287 | -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | GNU GENERAL PUBLIC LICENSE 2 | Version 3, 29 June 2007 3 | 4 | Copyright (C) 2007 Free Software Foundation, Inc. 5 | Everyone is permitted to copy and distribute verbatim copies 6 | of this license document, but changing it is not allowed. 7 | 8 | Preamble 9 | 10 | The GNU General Public License is a free, copyleft license for 11 | software and other kinds of works. 12 | 13 | The licenses for most software and other practical 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Such new versions will 567 | be similar in spirit to the present version, but may differ in detail to 568 | address new problems or concerns. 569 | 570 | Each version is given a distinguishing version number. If the 571 | Program specifies that a certain numbered version of the GNU General 572 | Public License "or any later version" applies to it, you have the 573 | option of following the terms and conditions either of that numbered 574 | version or of any later version published by the Free Software 575 | Foundation. If the Program does not specify a version number of the 576 | GNU General Public License, you may choose any version ever published 577 | by the Free Software Foundation. 578 | 579 | If the Program specifies that a proxy can decide which future 580 | versions of the GNU General Public License can be used, that proxy's 581 | public statement of acceptance of a version permanently authorizes you 582 | to choose that version for the Program. 583 | 584 | Later license versions may give you additional or different 585 | permissions. However, no additional obligations are imposed on any 586 | author or copyright holder as a result of your choosing to follow a 587 | later version. 588 | 589 | 15. Disclaimer of Warranty. 590 | 591 | THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY 592 | APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT 593 | HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY 594 | OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, 595 | THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 596 | PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM 597 | IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF 598 | ALL NECESSARY SERVICING, REPAIR OR CORRECTION. 599 | 600 | 16. Limitation of Liability. 601 | 602 | IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING 603 | WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS 604 | THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY 605 | GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE 606 | USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF 607 | DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD 608 | PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), 609 | EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF 610 | SUCH DAMAGES. 611 | 612 | 17. Interpretation of Sections 15 and 16. 613 | 614 | If the disclaimer of warranty and limitation of liability provided 615 | above cannot be given local legal effect according to their terms, 616 | reviewing courts shall apply local law that most closely approximates 617 | an absolute waiver of all civil liability in connection with the 618 | Program, unless a warranty or assumption of liability accompanies a 619 | copy of the Program in return for a fee. 620 | 621 | END OF TERMS AND CONDITIONS 622 | 623 | How to Apply These Terms to Your New Programs 624 | 625 | If you develop a new program, and you want it to be of the greatest 626 | possible use to the public, the best way to achieve this is to make it 627 | free software which everyone can redistribute and change under these terms. 628 | 629 | To do so, attach the following notices to the program. It is safest 630 | to attach them to the start of each source file to most effectively 631 | state the exclusion of warranty; and each file should have at least 632 | the "copyright" line and a pointer to where the full notice is found. 633 | 634 | {one line to give the program's name and a brief idea of what it does.} 635 | Copyright (C) {year} {name of author} 636 | 637 | This program is free software: you can redistribute it and/or modify 638 | it under the terms of the GNU General Public License as published by 639 | the Free Software Foundation, either version 3 of the License, or 640 | (at your option) any later version. 641 | 642 | This program is distributed in the hope that it will be useful, 643 | but WITHOUT ANY WARRANTY; without even the implied warranty of 644 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 645 | GNU General Public License for more details. 646 | 647 | You should have received a copy of the GNU General Public License 648 | along with this program. If not, see . 649 | 650 | Also add information on how to contact you by electronic and paper mail. 651 | 652 | If the program does terminal interaction, make it output a short 653 | notice like this when it starts in an interactive mode: 654 | 655 | {project} Copyright (C) {year} {fullname} 656 | This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. 657 | This is free software, and you are welcome to redistribute it 658 | under certain conditions; type `show c' for details. 659 | 660 | The hypothetical commands `show w' and `show c' should show the appropriate 661 | parts of the General Public License. Of course, your program's commands 662 | might be different; for a GUI interface, you would use an "about box". 663 | 664 | You should also get your employer (if you work as a programmer) or school, 665 | if any, to sign a "copyright disclaimer" for the program, if necessary. 666 | For more information on this, and how to apply and follow the GNU GPL, see 667 | . 668 | 669 | The GNU General Public License does not permit incorporating your program 670 | into proprietary programs. If your program is a subroutine library, you 671 | may consider it more useful to permit linking proprietary applications with 672 | the library. If this is what you want to do, use the GNU Lesser General 673 | Public License instead of this License. But first, please read 674 | . 675 | --------------------------------------------------------------------------------