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