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 payload2 = type_.unpack(payload)
55 print 'RECV', command, repr(payload.encode('hex')), len(payload)
56 log.err(None, 'Error parsing message: (see RECV line)')
59 self.packetReceived(command, payload2)
61 def packetReceived(self, command, payload2):
62 handler = getattr(self, 'handle_' + command, None)
65 print 'no handler for', repr(command)
71 print 'RECV', command, repr(payload2)[:100]
72 log.err(None, 'Error handling message: (see RECV line)')
74 def sendPacket(self, command, payload2):
75 if len(command) >= 12:
76 raise ValueError('command too long')
77 type_ = getattr(self, 'message_' + command, None)
79 raise ValueError('invalid command')
80 #print 'SEND', command, repr(payload2)[:500]
81 payload = type_.pack(payload2)
82 if len(payload) > self._max_payload_length:
83 raise TooLong('payload too long')
84 self.transport.write(self._message_prefix + struct.pack('<12sI', command, len(payload)) + hashlib.sha256(hashlib.sha256(payload).digest()).digest()[:4] + payload)
86 def __getattr__(self, attr):
88 if attr.startswith(prefix):
89 command = attr[len(prefix):]
90 return lambda **payload2: self.sendPacket(command, payload2)
91 #return protocol.Protocol.__getattr__(self, attr)
92 raise AttributeError(attr)
94 class Protocol(BaseProtocol):
95 def __init__(self, net):
96 BaseProtocol.__init__(self, net.P2P_PREFIX, 1000000)
98 def connectionMade(self):
102 time=int(time.time()),
105 address=self.transport.getPeer().host,
106 port=self.transport.getPeer().port,
110 address=self.transport.getHost().host,
111 port=self.transport.getHost().port,
113 nonce=random.randrange(2**64),
118 message_version = pack.ComposedType([
119 ('version', pack.IntType(32)),
120 ('services', pack.IntType(64)),
121 ('time', pack.IntType(64)),
122 ('addr_to', bitcoin_data.address_type),
123 ('addr_from', bitcoin_data.address_type),
124 ('nonce', pack.IntType(64)),
125 ('sub_version_num', pack.VarStrType()),
126 ('start_height', pack.IntType(32)),
128 def handle_version(self, version, services, time, addr_to, addr_from, nonce, sub_version_num, start_height):
131 message_verack = pack.ComposedType([])
132 def handle_verack(self):
133 self.get_block = deferral.ReplyMatcher(lambda hash: self.send_getdata(requests=[dict(type='block', hash=hash)]))
134 self.get_block_header = deferral.ReplyMatcher(lambda hash: self.send_getheaders(version=1, have=[], last=hash))
135 self.get_tx = deferral.ReplyMatcher(lambda hash: self.send_getdata(requests=[dict(type='tx', hash=hash)]))
137 if hasattr(self.factory, 'resetDelay'):
138 self.factory.resetDelay()
139 if hasattr(self.factory, 'gotConnection'):
140 self.factory.gotConnection(self)
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)),
148 def handle_inv(self, 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'])
155 print 'Unknown inv type', item
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)),
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))),
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))),
173 message_getaddr = pack.ComposedType([])
175 message_addr = pack.ComposedType([
176 ('addrs', pack.ListType(pack.ComposedType([
177 ('timestamp', pack.IntType(32)),
178 ('address', bitcoin_data.address_type),
181 def handle_addr(self, addrs):
185 message_tx = pack.ComposedType([
186 ('tx', bitcoin_data.tx_type),
188 def handle_tx(self, tx):
189 self.get_tx.got_response(bitcoin_data.hash256(bitcoin_data.tx_type.pack(tx)), tx)
191 message_block = pack.ComposedType([
192 ('block', bitcoin_data.block_type),
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'])
199 message_headers = pack.ComposedType([
200 ('headers', pack.ListType(bitcoin_data.block_type)),
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])
208 message_ping = pack.ComposedType([])
209 def handle_ping(self):
212 message_alert = pack.ComposedType([
213 ('message', pack.VarStrType()),
214 ('signature', pack.VarStrType()),
216 def handle_alert(self, message, signature):
217 print 'ALERT:', (message, signature)
219 def connectionLost(self, reason):
220 if hasattr(self.factory, 'gotConnection'):
221 self.factory.gotConnection(None)
222 print 'Bitcoin connection lost. Reason:', reason.getErrorMessage()
224 class ClientFactory(protocol.ReconnectingClientFactory):
229 def __init__(self, net):
231 self.conn = variable.Variable(None)
233 self.new_block = variable.Event()
234 self.new_tx = variable.Event()
235 self.new_headers = variable.Event()
237 def buildProtocol(self, addr):
238 p = self.protocol(self.net)
242 def gotConnection(self, conn):
245 def getProtocol(self):
246 return self.conn.get_not_none()
248 class HeaderWrapper(object):
250 __slots__ = 'hash previous_hash'.split(' ')
253 def from_header(cls, header):
254 return cls(bitcoin_data.hash256(bitcoin_data.block_header_type.pack(header)), header['previous_block'])
256 def __init__(self, hash, previous_hash):
257 self.hash, self.previous_hash = hash, previous_hash
259 class HeightTracker(object):
260 '''Point this at a factory and let it take care of getting block heights'''
262 def __init__(self, rpc_proxy, factory, backlog_needed):
263 self._rpc_proxy = rpc_proxy
264 self._factory = factory
265 self._backlog_needed = backlog_needed
267 self._tracker = forest.Tracker()
269 self._watch1 = self._factory.new_headers.watch(self._heard_headers)
270 self._watch2 = self._factory.new_block.watch(self._request)
272 self._requested = set()
273 self._clear_task = task.LoopingCall(self._requested.clear)
274 self._clear_task.start(60)
276 self._last_notified_size = 0
278 self.updated = variable.Event()
280 self._think_task = task.LoopingCall(self._think)
281 self._think_task.start(15)
282 self._think2_task = task.LoopingCall(self._think2)
283 self._think2_task.start(15)
284 self.best_hash = None
288 highest_head = max(self._tracker.heads, key=lambda h: self._tracker.get_height_and_last(h)[0]) if self._tracker.heads else None
289 if highest_head is None:
290 return # wait for think2
291 height, last = self._tracker.get_height_and_last(highest_head)
292 if height < self._backlog_needed:
295 log.err(None, 'Error in HeightTracker._think:')
297 @defer.inlineCallbacks
300 ba = getwork.BlockAttempt.from_getwork((yield self._rpc_proxy.rpc_getwork()))
301 self._request(ba.previous_block)
302 self.best_hash = ba.previous_block
304 log.err(None, 'Error in HeightTracker._think2:')
306 def _heard_headers(self, headers):
308 for header in headers:
309 hw = HeaderWrapper.from_header(header)
310 if hw.hash in self._tracker.shares:
313 self._tracker.add(hw)
315 self.updated.happened()
318 if len(self._tracker.shares) >= self._last_notified_size + 100:
319 print 'Have %i/%i block headers' % (len(self._tracker.shares), self._backlog_needed)
320 self._last_notified_size = len(self._tracker.shares)
322 @defer.inlineCallbacks
323 def _request(self, last):
324 if last in self._tracker.shares:
326 if last in self._requested:
328 self._requested.add(last)
329 (yield self._factory.getProtocol()).send_getheaders(version=1, have=[], last=last)
331 def get_height_rel_highest(self, block_hash):
332 # callers: highest height can change during yields!
333 best_height, best_last = self._tracker.get_height_and_last(self.best_hash)
334 height, last = self._tracker.get_height_and_last(block_hash)
335 if last != best_last:
336 return -1000000000 # XXX hack
337 return height - best_height
339 if __name__ == '__main__':
340 from . import networks
341 factory = ClientFactory(networks.BitcoinMainnet)
342 reactor.connectTCP('127.0.0.1', 8333, factory)
346 @defer.inlineCallbacks
349 print (yield (yield factory.getProtocol()).get_block(0x000000000000003aaaf7638f9f9c0d0c60e8b0eb817dcdb55fd2b1964efc5175))
350 except defer.TimeoutError: