PyBitmessage/src/bmproto.py

350 lines
14 KiB
Python

import hashlib
import time
import socket
from network.advanceddispatcher import AdvancedDispatcher
import network.asyncore_pollchoose as asyncore
from network.proxy import Proxy, ProxyError, GeneralProxyError
from network.socks5 import Socks5Connection, Socks5Resolver, Socks5AuthError, Socks5Error
from network.socks4a import Socks4aConnection, Socks4aResolver, Socks4aError
import addresses
from bmconfigparser import BMConfigParser
import protocol
class BMProtoError(ProxyError): pass
class BMConnection(TLSDispatcher):
# ~1.6 MB which is the maximum possible size of an inv message.
maxMessageSize = 1600100
# protocol specification says max 1000 addresses in one addr command
maxAddrCount = 1000
# protocol specification says max 50000 objects in one inv command
maxObjectCount = 50000
def __init__(self, address=None, sock=None):
AdvancedDispatcher.__init__(self, sock)
self.verackReceived = False
self.verackSent = False
if address is None and sock is not None:
self.destination = self.addr()
self.isOutbound = False
TLSHandshake.__init__(self, sock, server_side=True)
print "received connection in background from %s:%i" % (self.destination[0], self.destination[1])
else:
self.destination = address
self.isOutbound = True
self.create_socket(socket.AF_INET, socket.SOCK_STREAM)
self.connect(self.destination)
TLSHandshake.__init__(self, sock, server_side=False)
print "connecting in background to %s:%i" % (self.destination[0], self.destination[1])
def bm_proto_reset(self):
self.magic = None
self.command = None
self.payloadLength = None
self.checksum = None
self.payload = None
self.invalid = False
def state_init(self):
self.bm_proto_reset()
self.write_buf += protocol.assembleVersionMessage(self.destination[0], self.destination[1], (1,), False)
if True:
print "Sending version (%ib)" % len(self.write_buf)
self.set_state("bm_header", 0)
return False
def state_bm_ready(self):
self.sendAddr()
self.sendBigInv()
return True
def state_bm_header(self):
if len(self.read_buf) < protocol.Header.size:
print "Length below header size"
return False
self.magic, self.command, self.payloadLength, self.checksum = protocol.Header.unpack(self.read_buf[:protocol.Header.size])
self.command = self.command.rstrip('\x00')
if self.magic != 0xE9BEB4D9:
# skip 1 byte in order to sync
self.bm_proto_reset()
self.set_state("bm_header", 1)
print "Bad magic"
if self.payloadLength > BMConnection.maxMessageSize:
self.invalid = True
self.set_state("bm_command", protocol.Header.size)
return True
def state_bm_command(self):
if len(self.read_buf) < self.payloadLength:
print "Length below announced object length"
return False
print "received %s (%ib)" % (self.command, self.payloadLength)
self.payload = self.read_buf[:self.payloadLength]
if self.checksum != hashlib.sha512(self.payload).digest()[0:4]:
print "Bad checksum, ignoring"
self.invalid = True
retval = True
if not self.invalid:
try:
retval = getattr(self, "bm_command_" + str(self.command).lower())()
except AttributeError:
# unimplemented command
print "unimplemented command %s" % (self.command)
else:
print "Skipping command %s due to invalid data" % (self.command)
if retval:
self.set_state("bm_header", self.payloadLength)
self.bm_proto_reset()
# else assume the command requires a different state to follow
return True
def bm_command_error(self):
def bm_command_getdata(self):
def bm_command_object(self):
def bm_command_ping(self):
def bm_command_pong(self):
def bm_command_verack(self):
self.verackReceived = True
return True
def bm_command_version(self):
self.remoteProtocolVersion, self.services, self.timestamp, padding1, self.myExternalIP, padding2, self.remoteNodeIncomingPort = protocol.VersionPacket.unpack(self.payload[:protocol.VersionPacket.size])
print "remoteProtocolVersion: %i" % (self.remoteProtocolVersion)
print "services: %08X" % (self.services)
print "time offset: %i" % (self.timestamp - int(time.time()))
print "my external IP: %s" % (socket.inet_ntoa(self.myExternalIP))
print "remote node incoming port: %i" % (self.remoteNodeIncomingPort)
useragentLength, lengthOfUseragentVarint = addresses.decodeVarint(self.payload[80:84])
readPosition = 80 + lengthOfUseragentVarint
self.userAgent = self.payload[readPosition:readPosition + useragentLength]
readPosition += useragentLength
print "user agent: %s" % (self.userAgent)
if not self.peerValidityChecks():
# TODO ABORT
return True
self.write_buf += protocol.CreatePacket('verack')
self.verackSent = True
if ((self.services & protocol.NODE_SSL == protocol.NODE_SSL) and
protocol.haveSSL(not self.isOutbound)):
self.isSSL = True
if self.verackReceived:
if self.isSSL:
self.set_state("tls_init", self.payloadLength)
else:
self.set_state("bm_ready", self.payloadLength)
self.bm_proto_reset()
return False
def peerValidityChecks(self):
if self.remoteProtocolVersion < 3:
self.write_buf += protocol.assembleErrorMessage(fatal=2,
errorText="Your is using an old protocol. Closing connection.")
logger.debug ('Closing connection to old protocol version %s, node: %s',
str(self.remoteProtocolVersion), str(self.peer))
return False
if self.timeOffset > 3600:
self.write_buf += protocol.assembleErrorMessage(fatal=2,
errorText="Your time is too far in the future compared to mine. Closing connection.")
logger.info("%s's time is too far in the future (%s seconds). Closing connection to it.",
self.peer, self.timeOffset)
shared.timeOffsetWrongCount += 1
return False
elif self.timeOffset < -3600:
self.write_buf += protocol.assembleErrorMessage(fatal=2,
errorText="Your time is too far in the past compared to mine. Closing connection.")
logger.info("%s's time is too far in the past (timeOffset %s seconds). Closing connection to it.",
self.peer, self.timeOffset)
shared.timeOffsetWrongCount += 1
return False
else:
shared.timeOffsetWrongCount = 0
if len(self.streams) == 0:
self.write_buf += protocol.assembleErrorMessage(fatal=2,
errorText="We don't have shared stream interests. Closing connection.")))
logger.debug ('Closed connection to %s because there is no overlapping interest in streams.',
str(self.peer))
return False
return True
def sendAddr(self):
def sendChunk():
if numberOfAddressesInAddrMessage == 0:
return
self.write_buf += protocol.CreatePacket('addr', \
addresses.encodeVarint(numberOfAddressesInAddrMessage) + payload)))
# We are going to share a maximum number of 1000 addrs (per overlapping
# stream) with our peer. 500 from overlapping streams, 250 from the
# left child stream, and 250 from the right child stream.
maxAddrCount = BMConfigParser().safeGetInt("bitmessagesettings", "maxaddrperstreamsend", 500)
# init
addressCount = 0
payload = ''
for stream in self.streams:
addrsInMyStream = {}
addrsInChildStreamLeft = {}
addrsInChildStreamRight = {}
with knownnodes.knownNodesLock:
if len(knownnodes.knownNodes[stream]) > 0:
filtered = {k: v for k, v in knownnodes.knownNodes[stream].items()
if v > (int(time.time()) - shared.maximumAgeOfNodesThatIAdvertiseToOthers)}
elemCount = len(filtered)
if elemCount > maxAddrCount:
elemCount = maxAddrCount
# only if more recent than 3 hours
addrsInMyStream = random.sample(filtered.items(), elemCount)
# sent 250 only if the remote isn't interested in it
if len(knownnodes.knownNodes[stream * 2]) > 0 and stream not in self.streams:
filtered = {k: v for k, v in knownnodes.knownNodes[stream*2].items()
if v > (int(time.time()) - shared.maximumAgeOfNodesThatIAdvertiseToOthers)}
elemCount = len(filtered)
if elemCount > maxAddrCount / 2:
elemCount = int(maxAddrCount / 2)
addrsInChildStreamLeft = random.sample(filtered.items(), elemCount)
if len(knownnodes.knownNodes[(stream * 2) + 1]) > 0 and stream not in self.streams:
filtered = {k: v for k, v in knownnodes.knownNodes[stream*2+1].items()
if v > (int(time.time()) - shared.maximumAgeOfNodesThatIAdvertiseToOthers)}
elemCount = len(filtered)
if elemCount > maxAddrCount / 2:
elemCount = int(maxAddrCount / 2)
addrsInChildStreamRight = random.sample(filtered.items(), elemCount)
for (HOST, PORT), timeLastReceivedMessageFromThisNode in addrsInMyStream:
addressCount += 1
payload += pack(
'>Q', timeLastReceivedMessageFromThisNode) # 64-bit time
payload += pack('>I', stream)
payload += pack(
'>q', 1) # service bit flags offered by this node
payload += protocol.encodeHost(HOST)
payload += pack('>H', PORT) # remote port
if addressCount >= BMConnection.maxAddrCount:
sendChunk()
payload = ''
addressCount = 0
for (HOST, PORT), timeLastReceivedMessageFromThisNode in addrsInChildStreamLeft:
addressCount += 1
payload += pack(
'>Q', timeLastReceivedMessageFromThisNode) # 64-bit time
payload += pack('>I', stream * 2)
payload += pack(
'>q', 1) # service bit flags offered by this node
payload += protocol.encodeHost(HOST)
payload += pack('>H', PORT) # remote port
if addressCount >= BMConnection.maxAddrCount:
sendChunk()
payload = ''
addressCount = 0
for (HOST, PORT), timeLastReceivedMessageFromThisNode in addrsInChildStreamRight:
addressCount += 1
payload += pack(
'>Q', timeLastReceivedMessageFromThisNode) # 64-bit time
payload += pack('>I', (stream * 2) + 1)
payload += pack(
'>q', 1) # service bit flags offered by this node
payload += protocol.encodeHost(HOST)
payload += pack('>H', PORT) # remote port
if addressCount >= BMConnection.maxAddrCount:
sendChunk()
payload = ''
addressCount = 0
# flush
sendChunk()
def sendBigInv(self):
def sendChunk():
if objectCount == 0:
return
payload = encodeVarint(objectCount) + payload
logger.debug('Sending huge inv message with %i objects to just this one peer',
str(numberOfObjects))
self.write_buf += protocol.CreatePacket('inv', payload)
# Select all hashes for objects in this stream.
bigInvList = {}
for stream in self.streams:
for hash in Inventory().unexpired_hashes_by_stream(stream):
if not self.objectHashHolderInstance.hasHash(hash):
bigInvList[hash] = 0
objectCount = 0
payload = ''
# Now let us start appending all of these hashes together. They will be
# sent out in a big inv message to our new peer.
for hash, storedValue in bigInvList.items():
payload += hash
objectCount += 1
if objectCount >= BMConnection.maxObjectCount:
self.sendChunk()
payload = ''
objectCount = 0
# flush
sendChunk()
class Socks5BMConnection(Socks5Connection, BMConnection):
def __init__(self, address):
Socks5Connection.__init__(self, address=address)
def state_socks_handshake_done(self):
BMConnection.state_init(self)
return False
class Socks4aBMConnection(Socks4aConnection, BMConnection):
def __init__(self, address):
Socks4aConnection.__init__(self, address=address)
def state_socks_handshake_done(self):
BMConnection.state_init(self)
return False
class BMServer(AdvancedDispatcher):
port = 8444
def __init__(self, port=None):
if not hasattr(self, '_map'):
AdvancedDispatcher.__init__(self)
self.create_socket(socket.AF_INET, socket.SOCK_STREAM)
self.set_reuse_addr()
if port is None:
port = BMServer.port
self.bind(('127.0.0.1', port))
self.connections = 0
self.listen(5)
def handle_accept(self):
pair = self.accept()
if pair is not None:
sock, addr = pair
BMConnection(sock=sock)
if __name__ == "__main__":
# initial fill
for host in (("127.0.0.1", 8448),):
direct = BMConnection(host)
while len(asyncore.socket_map) > 0:
print "loop, state = %s" % (direct.state)
asyncore.loop(timeout=1, count=1)
continue
proxy = Socks5BMConnection(host)
while len(asyncore.socket_map) > 0:
# print "loop, state = %s" % (proxy.state)
asyncore.loop(timeout=1, count=1)
proxy = Socks4aBMConnection(host)
while len(asyncore.socket_map) > 0:
# print "loop, state = %s" % (proxy.state)
asyncore.loop(timeout=1, count=1)