2 - Copyright (C) 2015-2016 Ramakrishnan Muthukrishnan <ram@rkrishnan.org>
4 - This file is part of FuncTorrent.
6 - FuncTorrent is free software; you can redistribute it and/or modify
7 - it under the terms of the GNU General Public License as published by
8 - the Free Software Foundation; either version 3 of the License, or
9 - (at your option) any later version.
11 - FuncTorrent is distributed in the hope that it will be useful,
12 - but WITHOUT ANY WARRANTY; without even the implied warranty of
13 - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 - GNU General Public License for more details.
16 - You should have received a copy of the GNU General Public License
17 - along with FuncTorrent; if not, see <http://www.gnu.org/licenses/>
20 {-# LANGUAGE OverloadedStrings #-}
21 module FuncTorrent.Tracker.Udp
25 import Control.Applicative (liftA2)
26 import Control.Monad (liftM)
27 import Control.Concurrent.MVar (readMVar)
28 import Control.Monad.Reader (ReaderT, runReaderT, ask, liftIO)
29 import Data.Binary (Binary(..), encode, decode)
30 import Data.Binary.Get (Get, isEmpty, getWord32be, getWord64be, getByteString)
31 import Data.Binary.Put (putWord16be, putWord64be, putWord32be, putByteString)
32 import Data.ByteString (ByteString)
33 import qualified Data.ByteString.Char8 as BC
34 import Data.ByteString.Lazy (fromStrict, toStrict)
35 import Data.Word (Word16, Word32, Word64)
36 import Network.Socket (Socket, Family( AF_INET ), SocketType( Datagram ), defaultProtocol, SockAddr(..), socket, close, getAddrInfo, addrAddress, SockAddr(..))
37 import Network.Socket.ByteString (sendTo, recvFrom)
38 import System.Random (randomIO)
40 import FuncTorrent.Tracker.Types (TrackerEventState(..), TState(..))
41 import FuncTorrent.Utils (IP, Port, toIP, toPort, getHostname, getPort)
42 import qualified FuncTorrent.FileSystem as FS (MsgChannel, Stats(..), getStats)
44 -- UDP tracker: http://bittorrent.org/beps/bep_0015.html
50 data UDPRequest = ConnectReq Word32
51 | AnnounceReq Word64 Word32 ByteString String Word64 Word64 Word64 TrackerEventState Word16
52 | ScrapeReq Integer Integer ByteString
55 data UDPResponse = ConnectResp Word32 Word64 -- transaction_id connection_id
56 | AnnounceResp Word32 Word32 Word32 Word32 [(IP, Port)] -- transaction_id interval leechers seeders [(ip, port)]
57 | ScrapeResp Integer Integer Integer Integer
58 | ErrorResp Integer String
61 data UDPTrackerHandle = UDPTrackerHandle { sock :: Socket
66 actionToInteger :: Action -> Integer
67 actionToInteger Connect = 0
68 actionToInteger Announce = 1
69 actionToInteger Scrape = 2
71 intToAction :: Integer -> Action
72 intToAction 0 = Connect
73 intToAction 1 = Announce
74 intToAction 2 = Scrape
76 eventToInteger :: TrackerEventState -> Integer
77 eventToInteger None = 0
78 eventToInteger Completed = 1
79 eventToInteger Started = 2
80 eventToInteger Stopped = 3
82 instance Binary UDPRequest where
83 put (ConnectReq transId) = do
84 putWord64be 0x41727101980
85 putWord32be $ fromIntegral (actionToInteger Connect)
86 putWord32be (fromIntegral transId)
87 put (AnnounceReq connId transId infohash peerId down left up event port) = do
88 putWord64be $ fromIntegral connId
89 putWord32be $ fromIntegral (actionToInteger Announce)
90 putWord32be $ fromIntegral transId
91 putByteString infohash
92 putByteString (BC.pack peerId)
93 putWord64be (fromIntegral down)
94 putWord64be (fromIntegral left)
95 putWord64be (fromIntegral up)
96 putWord32be $ fromIntegral (eventToInteger event)
100 putWord16be $ fromIntegral port
101 put (ScrapeReq _ _ _) = undefined
104 instance Binary UDPResponse where
107 a <- getWord32be -- action
109 0 -> liftA2 ConnectResp (fromIntegral <$> getWord32be) (fromIntegral <$> getWord64be)
111 tid <- fromIntegral <$> getWord32be
112 interval' <- fromIntegral <$> getWord32be
113 l <- getWord32be -- leechers
114 s <- getWord32be -- seeders
115 ipportpairs <- getIPPortPairs -- [(ip, port)]
116 return $ AnnounceResp tid interval' l s ipportpairs
118 tid <- fromIntegral <$> getWord32be
122 return $ ScrapeResp tid 0 0 0
123 3 -> do -- error response
124 tid <- fromIntegral <$> getWord32be
125 bs <- getByteString 4
126 return $ ErrorResp tid $ BC.unpack bs
127 _ -> error ("unknown response action type: " ++ show a)
129 sendRequest :: UDPTrackerHandle -> ByteString -> IO ()
130 sendRequest h req = do
131 n <- sendTo (sock h) req (addr h)
132 -- sanity check with n?
135 recvResponse :: UDPTrackerHandle -> IO UDPResponse
137 (bs, saddr) <- recvFrom (sock h) (16*1024)
138 return $ decode $ fromStrict bs
140 connectRequest :: ReaderT UDPTrackerHandle IO Word32
143 tidi <- liftIO randomIO
144 let pkt = encode $ ConnectReq tidi
145 liftIO $ sendRequest h (toStrict pkt)
148 connectResponse :: Word32 -> ReaderT UDPTrackerHandle IO Word64
149 connectResponse tid = do
151 resp <- liftIO $ recvResponse h
152 -- check if nbytes is at least 16 bytes long
154 (ConnectResp tidr cid) ->
157 liftIO $ putStrLn "connect succeeded"
163 announceRequest :: Word64 -> ByteString -> String -> Word64 -> Word64 -> Word64 -> Word16 -> ReaderT UDPTrackerHandle IO Word32
164 announceRequest cid infohash peerId up down left port = do
166 tidi <- liftIO randomIO
167 let pkt = encode $ AnnounceReq cid tidi infohash peerId down left up None port
168 liftIO $ sendRequest h (toStrict pkt)
171 data PeerStats = PeerStats { leechers :: Word32
173 , peers :: [(IP, Port)]
176 announceResponse :: Word32 -> ReaderT UDPTrackerHandle IO PeerStats
177 announceResponse tid = do
179 resp <- liftIO $ recvResponse h
181 (AnnounceResp tidr interval ss ls xs) ->
184 liftIO $ putStrLn "announce succeeded"
185 return $ PeerStats ls ss xs
187 return $ PeerStats 0 0 []
188 _ -> return $ PeerStats 0 0 []
190 getIPPortPairs :: Get [(IP, Port)]
196 ip <- toIP <$> getByteString 4
197 port <- toPort <$> getByteString 2
198 ipportpairs <- getIPPortPairs
199 return $ (ip, port) : ipportpairs
201 startSession :: String -> Port -> IO UDPTrackerHandle
202 startSession host port = do
203 s <- socket AF_INET Datagram defaultProtocol
204 addrinfos <- getAddrInfo Nothing (Just host) (Just (show port))
205 let (SockAddrInet p ip) = addrAddress $ head addrinfos
206 putStrLn "connected to tracker"
207 return UDPTrackerHandle { sock = s
208 , addr = (SockAddrInet (fromIntegral port) ip) }
210 closeSession :: UDPTrackerHandle -> IO ()
211 closeSession (UDPTrackerHandle s _ _) = close s
213 trackerLoop :: String -> Port -> String -> ByteString -> FS.MsgChannel -> TState -> IO ()
214 trackerLoop url sport peerId infohash fschan tstate = do
215 st' <- FS.getStats fschan
217 let up = FS.bytesRead st
218 down = FS.bytesWritten st
220 host = getHostname url
221 putStrLn $ "host = " ++ (show host) ++ " port= " ++ (show port)
222 handle <- startSession host port
223 flip runReaderT handle $ do
225 cid <- connectResponse t1
226 t2 <- announceRequest cid infohash peerId (fromIntegral up) (fromIntegral down) (fromIntegral (left tstate)) (fromIntegral sport)
227 stats <- announceResponse t2
229 -- _ <- threadDelay $