p2pool/bitcoin/p2p.py

   1 '''
   2 Implementation of Bitcoin's p2p protocol
   3 '''
   4
   5 from __future__ import division
   6
   7 import hashlib
   8 import random
   9 import struct
  10 import time
  11
  12 from twisted.internet import defer, protocol, reactor, task
  13 from twisted.python import log
  14
  15 import p2pool
  16 from . import data as bitcoin_data, getwork
  17 from p2pool.util import variable, datachunker, deferral, forest, pack
  18
  19 class TooLong(Exception):
  20     pass
  21
  22 class BaseProtocol(protocol.Protocol):
  23     def __init__(self, message_prefix, max_payload_length):
  24         self._message_prefix = message_prefix
  25         self._max_payload_length = max_payload_length
  26         self.dataReceived = datachunker.DataChunker(self.dataReceiver())
  27
  28     def dataReceiver(self):
  29         while True:
  30             start = ''
  31             while start != self._message_prefix:
  32                 start = (start + (yield 1))[-len(self._message_prefix):]
  33
  34             command = (yield 12).rstrip('\0')
  35             length, = struct.unpack('<I', (yield 4))
  36             if length > self._max_payload_length:
  37                 print 'length too large'
  38                 continue
  39             checksum = yield 4
  40             payload = yield length
  41
  42             if hashlib.sha256(hashlib.sha256(payload).digest()).digest()[:4] != checksum:
  43                 print 'invalid hash for', self.transport.getPeer().host, repr(command), length, checksum.encode('hex'), hashlib.sha256(hashlib.sha256(payload).digest()).digest()[:4].encode('hex'), payload.encode('hex')
  44                 continue
  45
  46             type_ = getattr(self, 'message_' + command, None)
  47             if type_ is None:
  48                 if p2pool.DEBUG:
  49                     print 'no type for', repr(command)
  50                 continue
  51
  52             try:
  53                 self.packetReceived(command, type_.unpack(payload))
  54             except:
  55                 print 'RECV', command, payload[:100].encode('hex') + ('...' if len(payload) > 100 else '')
  56                 log.err(None, 'Error handling message: (see RECV line)')
  57                 self.badPeerHappened()
  58
  59     def packetReceived(self, command, payload2):
  60         handler = getattr(self, 'handle_' + command, None)
  61         if handler is None:
  62             if p2pool.DEBUG:
  63                 print 'no handler for', repr(command)
  64             return
  65
  66         handler(**payload2)
  67
  68     def badPeerHappened(self):
  69         self.transport.loseConnection()
  70
  71     def sendPacket(self, command, payload2):
  72         if len(command) >= 12:
  73             raise ValueError('command too long')
  74         type_ = getattr(self, 'message_' + command, None)
  75         if type_ is None:
  76             raise ValueError('invalid command')
  77         #print 'SEND', command, repr(payload2)[:500]
  78         payload = type_.pack(payload2)
  79         if len(payload) > self._max_payload_length:
  80             raise TooLong('payload too long')
  81         self.transport.write(self._message_prefix + struct.pack('<12sI', command, len(payload)) + hashlib.sha256(hashlib.sha256(payload).digest()).digest()[:4] + payload)
  82
  83     def __getattr__(self, attr):
  84         prefix = 'send_'
  85         if attr.startswith(prefix):
  86             command = attr[len(prefix):]
  87             return lambda **payload2: self.sendPacket(command, payload2)
  88         #return protocol.Protocol.__getattr__(self, attr)
  89         raise AttributeError(attr)
  90
  91 class Protocol(BaseProtocol):
  92     def __init__(self, net):
  93         BaseProtocol.__init__(self, net.P2P_PREFIX, 1000000)
  94
  95     def connectionMade(self):
  96         self.send_version(
  97             version=32200,
  98             services=1,
  99             time=int(time.time()),
 100             addr_to=dict(
 101                 services=1,
 102                 address=self.transport.getPeer().host,
 103                 port=self.transport.getPeer().port,
 104             ),
 105             addr_from=dict(
 106                 services=1,
 107                 address=self.transport.getHost().host,
 108                 port=self.transport.getHost().port,
 109             ),
 110             nonce=random.randrange(2**64),
 111             sub_version_num='',
 112             start_height=0,
 113         )
 114
 115     message_version = pack.ComposedType([
 116         ('version', pack.IntType(32)),
 117         ('services', pack.IntType(64)),
 118         ('time', pack.IntType(64)),
 119         ('addr_to', bitcoin_data.address_type),
 120         ('addr_from', bitcoin_data.address_type),
 121         ('nonce', pack.IntType(64)),
 122         ('sub_version_num', pack.VarStrType()),
 123         ('start_height', pack.IntType(32)),
 124     ])
 125     def handle_version(self, version, services, time, addr_to, addr_from, nonce, sub_version_num, start_height):
 126         self.send_verack()
 127
 128     message_verack = pack.ComposedType([])
 129     def handle_verack(self):
 130         self.get_block = deferral.ReplyMatcher(lambda hash: self.send_getdata(requests=[dict(type='block', hash=hash)]))
 131         self.get_block_header = deferral.ReplyMatcher(lambda hash: self.send_getheaders(version=1, have=[], last=hash))
 132         self.get_tx = deferral.ReplyMatcher(lambda hash: self.send_getdata(requests=[dict(type='tx', hash=hash)]))
 133
 134         if hasattr(self.factory, 'resetDelay'):
 135             self.factory.resetDelay()
 136         if hasattr(self.factory, 'gotConnection'):
 137             self.factory.gotConnection(self)
 138
 139         self.pinger = task.LoopingCall(self.send_ping)
 140         self.pinger.start(30)
 141
 142     message_inv = pack.ComposedType([
 143         ('invs', pack.ListType(pack.ComposedType([
 144             ('type', pack.EnumType(pack.IntType(32), {'tx': 1, 'block': 2})),
 145             ('hash', pack.IntType(256)),
 146         ]))),
 147     ])
 148     def handle_inv(self, invs):
 149         for inv in invs:
 150             if inv['type'] == 'tx':
 151                 self.factory.new_tx.happened(inv['hash'])
 152             elif inv['type'] == 'block':
 153                 self.factory.new_block.happened(inv['hash'])
 154             else:
 155                 print 'Unknown inv type', item
 156
 157     message_getdata = pack.ComposedType([
 158         ('requests', pack.ListType(pack.ComposedType([
 159             ('type', pack.EnumType(pack.IntType(32), {'tx': 1, 'block': 2})),
 160             ('hash', pack.IntType(256)),
 161         ]))),
 162     ])
 163     message_getblocks = pack.ComposedType([
 164         ('version', pack.IntType(32)),
 165         ('have', pack.ListType(pack.IntType(256))),
 166         ('last', pack.PossiblyNoneType(0, pack.IntType(256))),
 167     ])
 168     message_getheaders = pack.ComposedType([
 169         ('version', pack.IntType(32)),
 170         ('have', pack.ListType(pack.IntType(256))),
 171         ('last', pack.PossiblyNoneType(0, pack.IntType(256))),
 172     ])
 173     message_getaddr = pack.ComposedType([])
 174
 175     message_addr = pack.ComposedType([
 176         ('addrs', pack.ListType(pack.ComposedType([
 177             ('timestamp', pack.IntType(32)),
 178             ('address', bitcoin_data.address_type),
 179         ]))),
 180     ])
 181     def handle_addr(self, addrs):
 182         for addr in addrs:
 183             pass
 184
 185     message_tx = pack.ComposedType([
 186         ('tx', bitcoin_data.tx_type),
 187     ])
 188     def handle_tx(self, tx):
 189         self.get_tx.got_response(bitcoin_data.hash256(bitcoin_data.tx_type.pack(tx)), tx)
 190
 191     message_block = pack.ComposedType([
 192         ('block', bitcoin_data.block_type),
 193     ])
 194     def handle_block(self, block):
 195         block_hash = bitcoin_data.hash256(bitcoin_data.block_header_type.pack(block['header']))
 196         self.get_block.got_response(block_hash, block)
 197         self.get_block_header.got_response(block_hash, block['header'])
 198
 199     message_headers = pack.ComposedType([
 200         ('headers', pack.ListType(bitcoin_data.block_type)),
 201     ])
 202     def handle_headers(self, headers):
 203         for header in headers:
 204             header = header['header']
 205             self.get_block_header.got_response(bitcoin_data.hash256(bitcoin_data.block_header_type.pack(header)), header)
 206         self.factory.new_headers.happened([header['header'] for header in headers])
 207
 208     message_ping = pack.ComposedType([])
 209     def handle_ping(self):
 210         pass
 211
 212     message_alert = pack.ComposedType([
 213         ('message', pack.VarStrType()),
 214         ('signature', pack.VarStrType()),
 215     ])
 216     def handle_alert(self, message, signature):
 217         print 'ALERT:', (message, signature)
 218
 219     def connectionLost(self, reason):
 220         if hasattr(self.factory, 'gotConnection'):
 221             self.factory.gotConnection(None)
 222         if hasattr(self, 'pinger'):
 223             self.pinger.stop()
 224         print 'Bitcoin connection lost. Reason:', reason.getErrorMessage()
 225
 226 class ClientFactory(protocol.ReconnectingClientFactory):
 227     protocol = Protocol
 228
 229     maxDelay = 1
 230
 231     def __init__(self, net):
 232         self.net = net
 233         self.conn = variable.Variable(None)
 234
 235         self.new_block = variable.Event()
 236         self.new_tx = variable.Event()
 237         self.new_headers = variable.Event()
 238
 239     def buildProtocol(self, addr):
 240         p = self.protocol(self.net)
 241         p.factory = self
 242         return p
 243
 244     def gotConnection(self, conn):
 245         self.conn.set(conn)
 246
 247     def getProtocol(self):
 248         return self.conn.get_not_none()
 249
 250 class HeaderWrapper(object):
 251     target = 2**256 - 1
 252     __slots__ = 'hash previous_hash'.split(' ')
 253
 254     @classmethod
 255     def from_header(cls, header):
 256         return cls(bitcoin_data.hash256(bitcoin_data.block_header_type.pack(header)), header['previous_block'])
 257
 258     def __init__(self, hash, previous_hash):
 259         self.hash, self.previous_hash = hash, previous_hash
 260
 261 class HeightTracker(object):
 262     '''Point this at a factory and let it take care of getting block heights'''
 263
 264     def __init__(self, rpc_proxy, factory, backlog_needed):
 265         self._rpc_proxy = rpc_proxy
 266         self._factory = factory
 267         self._backlog_needed = backlog_needed
 268
 269         self._tracker = forest.Tracker()
 270
 271         self._watch1 = self._factory.new_headers.watch(self._heard_headers)
 272         self._watch2 = self._factory.new_block.watch(self._request)
 273
 274         self._requested = set()
 275         self._clear_task = task.LoopingCall(self._requested.clear)
 276         self._clear_task.start(60)
 277
 278         self._last_notified_size = 0
 279
 280         self.updated = variable.Event()
 281
 282         self._think_task = task.LoopingCall(self._think)
 283         self._think_task.start(15)
 284         self._think2_task = task.LoopingCall(self._think2)
 285         self._think2_task.start(15)
 286         self.best_hash = None
 287
 288     def _think(self):
 289         try:
 290             highest_head = max(self._tracker.heads, key=lambda h: self._tracker.get_height_and_last(h)[0]) if self._tracker.heads else None
 291             if highest_head is None:
 292                 return # wait for think2
 293             height, last = self._tracker.get_height_and_last(highest_head)
 294             if height < self._backlog_needed:
 295                 self._request(last)
 296         except:
 297             log.err(None, 'Error in HeightTracker._think:')
 298
 299     @defer.inlineCallbacks
 300     def _think2(self):
 301         try:
 302             ba = getwork.BlockAttempt.from_getwork((yield self._rpc_proxy.rpc_getwork()))
 303             self._request(ba.previous_block)
 304             self.best_hash = ba.previous_block
 305         except:
 306             log.err(None, 'Error in HeightTracker._think2:')
 307
 308     def _heard_headers(self, headers):
 309         changed = False
 310         for header in headers:
 311             hw = HeaderWrapper.from_header(header)
 312             if hw.hash in self._tracker.shares:
 313                 continue
 314             changed = True
 315             self._tracker.add(hw)
 316         if changed:
 317             self.updated.happened()
 318         self._think()
 319
 320         if len(self._tracker.shares) >= self._last_notified_size + 100:
 321             print 'Have %i/%i block headers' % (len(self._tracker.shares), self._backlog_needed)
 322             self._last_notified_size = len(self._tracker.shares)
 323
 324     @defer.inlineCallbacks
 325     def _request(self, last):
 326         if last in self._tracker.shares:
 327             return
 328         if last in self._requested:
 329             return
 330         self._requested.add(last)
 331         (yield self._factory.getProtocol()).send_getheaders(version=1, have=[], last=last)
 332
 333     def get_height_rel_highest(self, block_hash):
 334         # callers: highest height can change during yields!
 335         best_height, best_last = self._tracker.get_height_and_last(self.best_hash)
 336         height, last = self._tracker.get_height_and_last(block_hash)
 337         if last != best_last:
 338             return -1000000000 # XXX hack
 339         return height - best_height
 340
 341 if __name__ == '__main__':
 342     from . import networks
 343     factory = ClientFactory(networks.BitcoinMainnet)
 344     reactor.connectTCP('127.0.0.1', 8333, factory)
 345
 346     @repr
 347     @apply
 348     @defer.inlineCallbacks
 349     def think():
 350         try:
 351             print (yield (yield factory.getProtocol()).get_block(0x000000000000003aaaf7638f9f9c0d0c60e8b0eb817dcdb55fd2b1964efc5175))
 352         except defer.TimeoutError:
 353             print "timeout"
 354         reactor.stop()
 355
 356     reactor.run()