2 Implementation of Bitcoin's p2p protocol
5 from __future__ import division
12 from twisted.internet import defer, protocol, reactor, task
13 from twisted.python import log
16 from . import data as bitcoin_data, getwork
17 from p2pool.util import variable, datachunker, deferral, forest, pack
19 class TooLong(Exception):
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())
28 def dataReceiver(self):
31 while start != self._message_prefix:
32 start = (start + (yield 1))[-len(self._message_prefix):]
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'
40 payload = yield length
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')
46 type_ = getattr(self, 'message_' + command, None)
49 print 'no type for', repr(command)
53 self.packetReceived(command, type_.unpack(payload))
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()
59 def packetReceived(self, command, payload2):
60 handler = getattr(self, 'handle_' + command, None)
63 print 'no handler for', repr(command)
68 def badPeerHappened(self):
69 self.transport.loseConnection()
71 def sendPacket(self, command, payload2):
72 if len(command) >= 12:
73 raise ValueError('command too long')
74 type_ = getattr(self, 'message_' + command, 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)
83 def __getattr__(self, attr):
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)
91 class Protocol(BaseProtocol):
92 def __init__(self, net):
93 BaseProtocol.__init__(self, net.P2P_PREFIX, 1000000)
95 def connectionMade(self):
99 time=int(time.time()),
102 address=self.transport.getPeer().host,
103 port=self.transport.getPeer().port,
107 address=self.transport.getHost().host,
108 port=self.transport.getHost().port,
110 nonce=random.randrange(2**64),
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)),
125 def handle_version(self, version, services, time, addr_to, addr_from, nonce, sub_version_num, start_height):
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)]))
134 if hasattr(self.factory, 'resetDelay'):
135 self.factory.resetDelay()
136 if hasattr(self.factory, 'gotConnection'):
137 self.factory.gotConnection(self)
139 message_inv = pack.ComposedType([
140 ('invs', pack.ListType(pack.ComposedType([
141 ('type', pack.EnumType(pack.IntType(32), {'tx': 1, 'block': 2})),
142 ('hash', pack.IntType(256)),
145 def handle_inv(self, invs):
147 if inv['type'] == 'tx':
148 self.factory.new_tx.happened(inv['hash'])
149 elif inv['type'] == 'block':
150 self.factory.new_block.happened(inv['hash'])
152 print 'Unknown inv type', item
154 message_getdata = pack.ComposedType([
155 ('requests', pack.ListType(pack.ComposedType([
156 ('type', pack.EnumType(pack.IntType(32), {'tx': 1, 'block': 2})),
157 ('hash', pack.IntType(256)),
160 message_getblocks = pack.ComposedType([
161 ('version', pack.IntType(32)),
162 ('have', pack.ListType(pack.IntType(256))),
163 ('last', pack.PossiblyNoneType(0, pack.IntType(256))),
165 message_getheaders = pack.ComposedType([
166 ('version', pack.IntType(32)),
167 ('have', pack.ListType(pack.IntType(256))),
168 ('last', pack.PossiblyNoneType(0, pack.IntType(256))),
170 message_getaddr = pack.ComposedType([])
172 message_addr = pack.ComposedType([
173 ('addrs', pack.ListType(pack.ComposedType([
174 ('timestamp', pack.IntType(32)),
175 ('address', bitcoin_data.address_type),
178 def handle_addr(self, addrs):
182 message_tx = pack.ComposedType([
183 ('tx', bitcoin_data.tx_type),
185 def handle_tx(self, tx):
186 self.get_tx.got_response(bitcoin_data.hash256(bitcoin_data.tx_type.pack(tx)), tx)
188 message_block = pack.ComposedType([
189 ('block', bitcoin_data.block_type),
191 def handle_block(self, block):
192 block_hash = bitcoin_data.hash256(bitcoin_data.block_header_type.pack(block['header']))
193 self.get_block.got_response(block_hash, block)
194 self.get_block_header.got_response(block_hash, block['header'])
196 message_headers = pack.ComposedType([
197 ('headers', pack.ListType(bitcoin_data.block_type)),
199 def handle_headers(self, headers):
200 for header in headers:
201 header = header['header']
202 self.get_block_header.got_response(bitcoin_data.hash256(bitcoin_data.block_header_type.pack(header)), header)
203 self.factory.new_headers.happened([header['header'] for header in headers])
205 message_ping = pack.ComposedType([])
206 def handle_ping(self):
209 message_alert = pack.ComposedType([
210 ('message', pack.VarStrType()),
211 ('signature', pack.VarStrType()),
213 def handle_alert(self, message, signature):
214 print 'ALERT:', (message, signature)
216 def connectionLost(self, reason):
217 if hasattr(self.factory, 'gotConnection'):
218 self.factory.gotConnection(None)
219 print 'Bitcoin connection lost. Reason:', reason.getErrorMessage()
221 class ClientFactory(protocol.ReconnectingClientFactory):
226 def __init__(self, net):
228 self.conn = variable.Variable(None)
230 self.new_block = variable.Event()
231 self.new_tx = variable.Event()
232 self.new_headers = variable.Event()
234 def buildProtocol(self, addr):
235 p = self.protocol(self.net)
239 def gotConnection(self, conn):
242 def getProtocol(self):
243 return self.conn.get_not_none()
245 class HeaderWrapper(object):
247 __slots__ = 'hash previous_hash'.split(' ')
250 def from_header(cls, header):
251 return cls(bitcoin_data.hash256(bitcoin_data.block_header_type.pack(header)), header['previous_block'])
253 def __init__(self, hash, previous_hash):
254 self.hash, self.previous_hash = hash, previous_hash
256 class HeightTracker(object):
257 '''Point this at a factory and let it take care of getting block heights'''
259 def __init__(self, rpc_proxy, factory, backlog_needed):
260 self._rpc_proxy = rpc_proxy
261 self._factory = factory
262 self._backlog_needed = backlog_needed
264 self._tracker = forest.Tracker()
266 self._watch1 = self._factory.new_headers.watch(self._heard_headers)
267 self._watch2 = self._factory.new_block.watch(self._request)
269 self._requested = set()
270 self._clear_task = task.LoopingCall(self._requested.clear)
271 self._clear_task.start(60)
273 self._last_notified_size = 0
275 self.updated = variable.Event()
277 self._think_task = task.LoopingCall(self._think)
278 self._think_task.start(15)
279 self._think2_task = task.LoopingCall(self._think2)
280 self._think2_task.start(15)
281 self.best_hash = None
285 highest_head = max(self._tracker.heads, key=lambda h: self._tracker.get_height_and_last(h)[0]) if self._tracker.heads else None
286 if highest_head is None:
287 return # wait for think2
288 height, last = self._tracker.get_height_and_last(highest_head)
289 if height < self._backlog_needed:
292 log.err(None, 'Error in HeightTracker._think:')
294 @defer.inlineCallbacks
297 ba = getwork.BlockAttempt.from_getwork((yield self._rpc_proxy.rpc_getwork()))
298 self._request(ba.previous_block)
299 self.best_hash = ba.previous_block
301 log.err(None, 'Error in HeightTracker._think2:')
303 def _heard_headers(self, headers):
305 for header in headers:
306 hw = HeaderWrapper.from_header(header)
307 if hw.hash in self._tracker.shares:
310 self._tracker.add(hw)
312 self.updated.happened()
315 if len(self._tracker.shares) >= self._last_notified_size + 100:
316 print 'Have %i/%i block headers' % (len(self._tracker.shares), self._backlog_needed)
317 self._last_notified_size = len(self._tracker.shares)
319 @defer.inlineCallbacks
320 def _request(self, last):
321 if last in self._tracker.shares:
323 if last in self._requested:
325 self._requested.add(last)
326 (yield self._factory.getProtocol()).send_getheaders(version=1, have=[], last=last)
328 def get_height_rel_highest(self, block_hash):
329 # callers: highest height can change during yields!
330 best_height, best_last = self._tracker.get_height_and_last(self.best_hash)
331 height, last = self._tracker.get_height_and_last(block_hash)
332 if last != best_last:
333 return -1000000000 # XXX hack
334 return height - best_height
336 if __name__ == '__main__':
337 from . import networks
338 factory = ClientFactory(networks.BitcoinMainnet)
339 reactor.connectTCP('127.0.0.1', 8333, factory)
343 @defer.inlineCallbacks
346 print (yield (yield factory.getProtocol()).get_block(0x000000000000003aaaf7638f9f9c0d0c60e8b0eb817dcdb55fd2b1964efc5175))
347 except defer.TimeoutError: