1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
|
-- |
-- Copyright : (c) Sam Truzjan 2013
-- License : BSD3
-- Maintainer : pxqr.sta@gmail.com
-- Stability : experimental
-- Portability : portable
--
-- BitTorrent uses a \"distributed sloppy hash table\" (DHT) for
-- storing peer contact information for \"trackerless\" torrents. In
-- effect, each peer becomes a tracker.
--
-- Normally you don't need to import other DHT modules.
--
-- For more info see:
-- <http://www.bittorrent.org/beps/bep_0005.html>
--
{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE TemplateHaskell #-}
{-# LANGUAGE TypeOperators #-}
module Network.BitTorrent.DHT
( -- * Distributed Hash Table
DHT
, dht
, Network.BitTorrent.DHT.bootstrap
, Network.BitTorrent.DHT.lookup
, Network.BitTorrent.DHT.insert
, Network.BitTorrent.DHT.delete
) where
import Control.Applicative
import Control.Concurrent.Lifted hiding (yield)
import Control.Exception.Lifted
import Control.Monad as M
import Control.Monad.Logger
import Control.Monad.Trans
import Data.Conduit as C
import Data.Conduit.List as C
import Data.List as L
import Data.Monoid
import Data.Text as T
import Network.Socket (PortNumber)
import Text.PrettyPrint as PP hiding ((<>), ($$))
import Text.PrettyPrint.Class
import Data.Torrent.InfoHash
import Network.BitTorrent.Core
import Network.BitTorrent.DHT.Message
import Network.BitTorrent.DHT.Routing
import Network.BitTorrent.DHT.Session
import Network.KRPC
{-----------------------------------------------------------------------
-- Handlers
-----------------------------------------------------------------------}
pingH :: Address ip => NodeHandler ip
pingH = nodeHandler $ \ _ Ping -> do
$(logDebug) "ping received, sending pong"
return Ping
findNodeH :: Address ip => NodeHandler ip
findNodeH = nodeHandler $ \ _ (FindNode nid) -> do
$(logDebug) "find_node received, sending closest nodes back"
NodeFound <$> getClosest nid
getPeersH :: Address ip => NodeHandler ip
getPeersH = nodeHandler $ \ naddr (GetPeers ih) -> do
$(logDebug) "get_peers received, trying to find peers"
GotPeers <$> getPeerList ih <*> grantToken naddr
announceH :: Address ip => NodeHandler ip
announceH = nodeHandler $ \ naddr (Announce {..}) -> do
$(logDebug) "announce received, trying to check token"
checkToken naddr sessionToken
case fromAddr naddr of
Nothing -> throw $ KError ProtocolError "bad address" ""
Just paddr -> do
insertPeer topic paddr
return Announced
handlers :: Address ip => [NodeHandler ip]
handlers = [pingH, findNodeH, getPeersH, announceH]
{-----------------------------------------------------------------------
-- Query
-----------------------------------------------------------------------}
findNodeQ :: Address ip => NodeId -> Iteration ip NodeAddr NodeInfo
findNodeQ nid addr = do
NodeFound closest <- FindNode nid <@> addr
return $ Right closest
getPeersQ :: Address ip => InfoHash -> Iteration ip NodeInfo PeerAddr
getPeersQ topic NodeInfo {..} = do
GotPeers {..} <- GetPeers topic <@> nodeAddr
return peers
{-----------------------------------------------------------------------
-- DHT operations
-----------------------------------------------------------------------}
-- | Run DHT on specified port. <add note about resources>
dht :: Address ip
=> Options -- ^ normally you need to use 'Data.Default.def';
-> NodeAddr ip -- ^ address to bind this node;
-> DHT ip a -- ^ actions to run: 'bootstrap', 'lookup', etc;
-> IO a -- ^ result.
dht = runDHT handlers
{-# INLINE dht #-}
-- | One good node may be sufficient. The list of bootstrapping nodes
-- usually obtained from 'Data.Torrent.tNodes' field. Bootstrapping
-- process can take up to 5 minutes.
--
-- (TODO) This operation is asynchronous and do not block.
--
bootstrap :: Address ip => [NodeAddr ip] -> DHT ip ()
bootstrap startNodes = do
$(logInfoS) "bootstrap" "Start node bootstrapping"
M.mapM_ insertClosest startNodes
$(logInfoS) "bootstrap" "Node bootstrapping finished"
where
insertClosest addr = do
t <- getTable
unless (full t) $ do
nid <- getNodeId
result <- try $ FindNode nid <@> addr
case result of
Left e -> do
$(logWarnS) "bootstrap" $ T.pack $ show (e :: IOError)
Right (NodeFound closest) -> do
$(logDebug) $ "Get a list of closest nodes: " <>
T.pack (PP.render (pretty closest))
forM_ closest $ \ info @ NodeInfo {..} -> do
let prettyAddr = T.pack (show (pretty nodeAddr))
$(logInfoS) "bootstrap" $ "table detalization" <> prettyAddr
insertClosest nodeAddr
-- | Get list of peers which downloading this torrent.
--
-- (TODO) This operation is synchronous and do block.
--
lookup :: Address ip => InfoHash -> DHT ip `Source` [PeerAddr ip]
lookup topic = do -- TODO retry getClosestHash if bucket is empty
closest <- lift $ getClosestHash topic
sourceList [closest] $= search (getPeersQ topic)
-- | Announce that /this/ peer may have some pieces of the specified
-- torrent.
--
-- (TODO) This operation is asynchronous and do not block.
--
insert :: Address ip => InfoHash -> PortNumber -> DHT ip ()
insert ih port = do
nodes <- getClosestHash ih
forM_ (nodeAddr <$> nodes) $ \ addr -> do
-- GotPeers {..} <- GetPeers ih <@> addr
-- Announced <- Announce False ih undefined grantedToken <@> addr
return ()
-- | Stop announcing /this/ peer for the specified torrent.
--
-- This operation is atomic and do not block.
--
delete :: Address ip => InfoHash -> DHT ip ()
delete = error "DHT.delete: not implemented"
|
