import base64 from binascii import hexlify import hashlib import random import socket import ssl from struct import pack, unpack, Struct import sys import time import traceback from addresses import calculateInventoryHash, encodeVarint, decodeVarint, decodeAddress, varintDecodeError from configparser import BMConfigParser from debug import logger from helper_sql import sqlExecute import highlevelcrypto from inventory import Inventory import state from version import softwareVersion #Service flags NODE_NETWORK = 1 NODE_SSL = 2 #Bitfield flags BITFIELD_DOESACK = 1 eightBytesOfRandomDataUsedToDetectConnectionsToSelf = pack( '>Q', random.randrange(1, 18446744073709551615)) #If changed, these values will cause particularly unexpected behavior: You won't be able to either send or receive messages because the proof of work you do (or demand) won't match that done or demanded by others. Don't change them! networkDefaultProofOfWorkNonceTrialsPerByte = 1000 #The amount of work that should be performed (and demanded) per byte of the payload. networkDefaultPayloadLengthExtraBytes = 1000 #To make sending short messages a little more difficult, this value is added to the payload length for use in calculating the proof of work target. #Compiled struct for packing/unpacking headers #New code should use CreatePacket instead of Header.pack Header = Struct('!L12sL4s') # Bitfield def getBitfield(address): # bitfield of features supported by me (see the wiki). bitfield = 0 # send ack if not BMConfigParser().safeGetBoolean(address, 'dontsendack'): bitfield |= BITFIELD_DOESACK return pack('>I', bitfield) def checkBitfield(bitfieldBinary, flags): bitfield, = unpack('>I', bitfieldBinary) return (bitfield & flags) == flags def isBitSetWithinBitfield(fourByteString, n): # Uses MSB 0 bit numbering across 4 bytes of data n = 31 - n x, = unpack('>L', fourByteString) return x & 2**n != 0 # data handling def encodeHost(host): if host.find('.onion') > -1: return '\xfd\x87\xd8\x7e\xeb\x43' + base64.b32decode(host.split(".")[0], True) elif host.find(':') == -1: return '\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xFF\xFF' + \ socket.inet_aton(host) else: return socket.inet_pton(socket.AF_INET6, host) def networkType(host): if host.find('.onion') > -1: return 'onion' elif host.find(':') == -1: return 'IPv4' else: return 'IPv6' # checks def haveSSL(server = False): # python < 2.7.9's ssl library does not support ECDSA server due to missing initialisation of available curves, but client works ok if server == False: return True elif sys.version_info >= (2,7,9): return True return False def checkSocksIP(host): try: if state.socksIP is None or not state.socksIP: state.socksIP = socket.gethostbyname(BMConfigParser().get("bitmessagesettings", "sockshostname")) except NameError: state.socksIP = socket.gethostbyname(BMConfigParser().get("bitmessagesettings", "sockshostname")) return state.socksIP == host def isProofOfWorkSufficient(data, nonceTrialsPerByte=0, payloadLengthExtraBytes=0): if nonceTrialsPerByte < networkDefaultProofOfWorkNonceTrialsPerByte: nonceTrialsPerByte = networkDefaultProofOfWorkNonceTrialsPerByte if payloadLengthExtraBytes < networkDefaultPayloadLengthExtraBytes: payloadLengthExtraBytes = networkDefaultPayloadLengthExtraBytes endOfLifeTime, = unpack('>Q', data[8:16]) TTL = endOfLifeTime - int(time.time()) if TTL < 300: TTL = 300 POW, = unpack('>Q', hashlib.sha512(hashlib.sha512(data[ :8] + hashlib.sha512(data[8:]).digest()).digest()).digest()[0:8]) return POW <= 2 ** 64 / (nonceTrialsPerByte*(len(data) + payloadLengthExtraBytes + ((TTL*(len(data)+payloadLengthExtraBytes))/(2 ** 16)))) # Packet creation def CreatePacket(command, payload=''): payload_length = len(payload) checksum = hashlib.sha512(payload).digest()[0:4] b = bytearray(Header.size + payload_length) Header.pack_into(b, 0, 0xE9BEB4D9, command, payload_length, checksum) b[Header.size:] = payload return bytes(b) def assembleVersionMessage(remoteHost, remotePort, myStreamNumber, server = False): payload = '' payload += pack('>L', 3) # protocol version. payload += pack('>q', NODE_NETWORK|(NODE_SSL if haveSSL(server) else 0)) # bitflags of the services I offer. payload += pack('>q', int(time.time())) payload += pack( '>q', 1) # boolservices of remote connection; ignored by the remote host. if checkSocksIP(remoteHost) and server: # prevent leaking of tor outbound IP payload += encodeHost('127.0.0.1') payload += pack('>H', 8444) else: payload += encodeHost(remoteHost) payload += pack('>H', remotePort) # remote IPv6 and port payload += pack('>q', 1) # bitflags of the services I offer. payload += '\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xFF\xFF' + pack( '>L', 2130706433) # = 127.0.0.1. This will be ignored by the remote host. The actual remote connected IP will be used. # we have a separate extPort and # incoming over clearnet or # outgoing through clearnet if BMConfigParser().safeGetBoolean('bitmessagesettings', 'upnp') and state.extPort \ and ((server and not checkSocksIP(remoteHost)) or \ (BMConfigParser().get("bitmessagesettings", "socksproxytype") == "none" and not server)): payload += pack('>H', state.extPort) elif checkSocksIP(remoteHost) and server: # incoming connection over Tor payload += pack('>H', BMConfigParser().getint('bitmessagesettings', 'onionport')) else: # no extPort and not incoming over Tor payload += pack('>H', BMConfigParser().getint('bitmessagesettings', 'port')) random.seed() payload += eightBytesOfRandomDataUsedToDetectConnectionsToSelf userAgent = '/PyBitmessage:' + softwareVersion + '/' payload += encodeVarint(len(userAgent)) payload += userAgent payload += encodeVarint( 1) # The number of streams about which I care. PyBitmessage currently only supports 1 per connection. payload += encodeVarint(myStreamNumber) return CreatePacket('version', payload) def assembleErrorMessage(fatal=0, banTime=0, inventoryVector='', errorText=''): payload = encodeVarint(fatal) payload += encodeVarint(banTime) payload += encodeVarint(len(inventoryVector)) payload += inventoryVector payload += encodeVarint(len(errorText)) payload += errorText return CreatePacket('error', payload) # Packet decoding def decryptAndCheckPubkeyPayload(data, address): """ Version 4 pubkeys are encrypted. This function is run when we already have the address to which we want to try to send a message. The 'data' may come either off of the wire or we might have had it already in our inventory when we tried to send a msg to this particular address. """ try: status, addressVersion, streamNumber, ripe = decodeAddress(address) readPosition = 20 # bypass the nonce, time, and object type embeddedAddressVersion, varintLength = decodeVarint(data[readPosition:readPosition + 10]) readPosition += varintLength embeddedStreamNumber, varintLength = decodeVarint(data[readPosition:readPosition + 10]) readPosition += varintLength storedData = data[20:readPosition] # We'll store the address version and stream number (and some more) in the pubkeys table. if addressVersion != embeddedAddressVersion: logger.info('Pubkey decryption was UNsuccessful due to address version mismatch.') return 'failed' if streamNumber != embeddedStreamNumber: logger.info('Pubkey decryption was UNsuccessful due to stream number mismatch.') return 'failed' tag = data[readPosition:readPosition + 32] readPosition += 32 signedData = data[8:readPosition] # the time through the tag. More data is appended onto signedData below after the decryption. encryptedData = data[readPosition:] # Let us try to decrypt the pubkey toAddress, cryptorObject = state.neededPubkeys[tag] if toAddress != address: logger.critical('decryptAndCheckPubkeyPayload failed due to toAddress mismatch. This is very peculiar. toAddress: %s, address %s', toAddress, address) # the only way I can think that this could happen is if someone encodes their address data two different ways. # That sort of address-malleability should have been caught by the UI or API and an error given to the user. return 'failed' try: decryptedData = cryptorObject.decrypt(encryptedData) except: # Someone must have encrypted some data with a different key # but tagged it with a tag for which we are watching. logger.info('Pubkey decryption was unsuccessful.') return 'failed' readPosition = 0 bitfieldBehaviors = decryptedData[readPosition:readPosition + 4] readPosition += 4 publicSigningKey = '\x04' + decryptedData[readPosition:readPosition + 64] readPosition += 64 publicEncryptionKey = '\x04' + decryptedData[readPosition:readPosition + 64] readPosition += 64 specifiedNonceTrialsPerByte, specifiedNonceTrialsPerByteLength = decodeVarint( decryptedData[readPosition:readPosition + 10]) readPosition += specifiedNonceTrialsPerByteLength specifiedPayloadLengthExtraBytes, specifiedPayloadLengthExtraBytesLength = decodeVarint( decryptedData[readPosition:readPosition + 10]) readPosition += specifiedPayloadLengthExtraBytesLength storedData += decryptedData[:readPosition] signedData += decryptedData[:readPosition] signatureLength, signatureLengthLength = decodeVarint( decryptedData[readPosition:readPosition + 10]) readPosition += signatureLengthLength signature = decryptedData[readPosition:readPosition + signatureLength] if highlevelcrypto.verify(signedData, signature, hexlify(publicSigningKey)): logger.info('ECDSA verify passed (within decryptAndCheckPubkeyPayload)') else: logger.info('ECDSA verify failed (within decryptAndCheckPubkeyPayload)') return 'failed' sha = hashlib.new('sha512') sha.update(publicSigningKey + publicEncryptionKey) ripeHasher = hashlib.new('ripemd160') ripeHasher.update(sha.digest()) embeddedRipe = ripeHasher.digest() if embeddedRipe != ripe: # Although this pubkey object had the tag were were looking for and was # encrypted with the correct encryption key, it doesn't contain the # correct pubkeys. Someone is either being malicious or using buggy software. logger.info('Pubkey decryption was UNsuccessful due to RIPE mismatch.') return 'failed' # Everything checked out. Insert it into the pubkeys table. logger.info('within decryptAndCheckPubkeyPayload, addressVersion: %s, streamNumber: %s \n\ ripe %s\n\ publicSigningKey in hex: %s\n\ publicEncryptionKey in hex: %s', addressVersion, streamNumber, hexlify(ripe), hexlify(publicSigningKey), hexlify(publicEncryptionKey) ) t = (address, addressVersion, storedData, int(time.time()), 'yes') sqlExecute('''INSERT INTO pubkeys VALUES (?,?,?,?,?)''', *t) return 'successful' except varintDecodeError as e: logger.info('Pubkey decryption was UNsuccessful due to a malformed varint.') return 'failed' except Exception as e: logger.critical('Pubkey decryption was UNsuccessful because of an unhandled exception! This is definitely a bug! \n%s', traceback.format_exc()) return 'failed' def checkAndShareObjectWithPeers(data): """ This function is called after either receiving an object off of the wire or after receiving one as ackdata. Returns the length of time that we should reserve to process this message if we are receiving it off of the wire. """ if len(data) > 2 ** 18: logger.info('The payload length of this object is too large (%s bytes). Ignoring it.', len(data)) return 0 # Let us check to make sure that the proof of work is sufficient. if not isProofOfWorkSufficient(data): logger.info('Proof of work is insufficient.') return 0 endOfLifeTime, = unpack('>Q', data[8:16]) if endOfLifeTime - int(time.time()) > 28 * 24 * 60 * 60 + 10800: # The TTL may not be larger than 28 days + 3 hours of wiggle room logger.info('This object\'s End of Life time is too far in the future. Ignoring it. Time is %s', endOfLifeTime) return 0 if endOfLifeTime - int(time.time()) < - 3600: # The EOL time was more than an hour ago. That's too much. logger.info('This object\'s End of Life time was more than an hour ago. Ignoring the object. Time is %s', endOfLifeTime) return 0 intObjectType, = unpack('>I', data[16:20]) try: if intObjectType == 0: _checkAndShareGetpubkeyWithPeers(data) return 0.1 elif intObjectType == 1: _checkAndSharePubkeyWithPeers(data) return 0.1 elif intObjectType == 2: _checkAndShareMsgWithPeers(data) return 0.6 elif intObjectType == 3: _checkAndShareBroadcastWithPeers(data) return 0.6 else: _checkAndShareUndefinedObjectWithPeers(data) return 0.6 except varintDecodeError as e: logger.debug("There was a problem with a varint while checking to see whether it was appropriate to share an object with peers. Some details: %s", e) except Exception as e: logger.critical('There was a problem while checking to see whether it was appropriate to share an object with peers. This is definitely a bug! \n%s', traceback.format_exc()) return 0 def _checkAndShareUndefinedObjectWithPeers(data): embeddedTime, = unpack('>Q', data[8:16]) readPosition = 20 # bypass nonce, time, and object type objectVersion, objectVersionLength = decodeVarint( data[readPosition:readPosition + 9]) readPosition += objectVersionLength streamNumber, streamNumberLength = decodeVarint( data[readPosition:readPosition + 9]) if not streamNumber in state.streamsInWhichIAmParticipating: logger.debug('The streamNumber %s isn\'t one we are interested in.', streamNumber) return inventoryHash = calculateInventoryHash(data) if inventoryHash in Inventory(): logger.debug('We have already received this undefined object. Ignoring.') return objectType, = unpack('>I', data[16:20]) Inventory()[inventoryHash] = ( objectType, streamNumber, data, embeddedTime,'') logger.debug('advertising inv with hash: %s', hexlify(inventoryHash)) broadcastToSendDataQueues((streamNumber, 'advertiseobject', inventoryHash)) def _checkAndShareMsgWithPeers(data): embeddedTime, = unpack('>Q', data[8:16]) readPosition = 20 # bypass nonce, time, and object type objectVersion, objectVersionLength = decodeVarint( data[readPosition:readPosition + 9]) readPosition += objectVersionLength streamNumber, streamNumberLength = decodeVarint( data[readPosition:readPosition + 9]) if not streamNumber in state.streamsInWhichIAmParticipating: logger.debug('The streamNumber %s isn\'t one we are interested in.', streamNumber) return readPosition += streamNumberLength inventoryHash = calculateInventoryHash(data) if inventoryHash in Inventory(): logger.debug('We have already received this msg message. Ignoring.') return # This msg message is valid. Let's let our peers know about it. objectType = 2 Inventory()[inventoryHash] = ( objectType, streamNumber, data, embeddedTime,'') logger.debug('advertising inv with hash: %s', hexlify(inventoryHash)) broadcastToSendDataQueues((streamNumber, 'advertiseobject', inventoryHash)) # Now let's enqueue it to be processed ourselves. objectProcessorQueue.put((objectType,data)) def _checkAndShareGetpubkeyWithPeers(data): if len(data) < 42: logger.info('getpubkey message doesn\'t contain enough data. Ignoring.') return if len(data) > 200: logger.info('getpubkey is abnormally long. Sanity check failed. Ignoring object.') embeddedTime, = unpack('>Q', data[8:16]) readPosition = 20 # bypass the nonce, time, and object type requestedAddressVersionNumber, addressVersionLength = decodeVarint( data[readPosition:readPosition + 10]) readPosition += addressVersionLength streamNumber, streamNumberLength = decodeVarint( data[readPosition:readPosition + 10]) if not streamNumber in state.streamsInWhichIAmParticipating: logger.debug('The streamNumber %s isn\'t one we are interested in.', streamNumber) return readPosition += streamNumberLength inventoryHash = calculateInventoryHash(data) if inventoryHash in Inventory(): logger.debug('We have already received this getpubkey request. Ignoring it.') return objectType = 0 Inventory()[inventoryHash] = ( objectType, streamNumber, data, embeddedTime,'') # This getpubkey request is valid. Forward to peers. logger.debug('advertising inv with hash: %s', hexlify(inventoryHash)) broadcastToSendDataQueues((streamNumber, 'advertiseobject', inventoryHash)) # Now let's queue it to be processed ourselves. objectProcessorQueue.put((objectType,data)) def _checkAndSharePubkeyWithPeers(data): if len(data) < 146 or len(data) > 440: # sanity check return embeddedTime, = unpack('>Q', data[8:16]) readPosition = 20 # bypass the nonce, time, and object type addressVersion, varintLength = decodeVarint( data[readPosition:readPosition + 10]) readPosition += varintLength streamNumber, varintLength = decodeVarint( data[readPosition:readPosition + 10]) readPosition += varintLength if not streamNumber in state.streamsInWhichIAmParticipating: logger.debug('The streamNumber %s isn\'t one we are interested in.', streamNumber) return if addressVersion >= 4: tag = data[readPosition:readPosition + 32] logger.debug('tag in received pubkey is: %s', hexlify(tag)) else: tag = '' inventoryHash = calculateInventoryHash(data) if inventoryHash in Inventory(): logger.debug('We have already received this pubkey. Ignoring it.') return objectType = 1 Inventory()[inventoryHash] = ( objectType, streamNumber, data, embeddedTime, tag) # This object is valid. Forward it to peers. logger.debug('advertising inv with hash: %s', hexlify(inventoryHash)) broadcastToSendDataQueues((streamNumber, 'advertiseobject', inventoryHash)) # Now let's queue it to be processed ourselves. objectProcessorQueue.put((objectType,data)) def _checkAndShareBroadcastWithPeers(data): if len(data) < 180: logger.debug('The payload length of this broadcast packet is unreasonably low. Someone is probably trying funny business. Ignoring message.') return embeddedTime, = unpack('>Q', data[8:16]) readPosition = 20 # bypass the nonce, time, and object type broadcastVersion, broadcastVersionLength = decodeVarint( data[readPosition:readPosition + 10]) readPosition += broadcastVersionLength if broadcastVersion >= 2: streamNumber, streamNumberLength = decodeVarint(data[readPosition:readPosition + 10]) readPosition += streamNumberLength if not streamNumber in state.streamsInWhichIAmParticipating: logger.debug('The streamNumber %s isn\'t one we are interested in.', streamNumber) return if broadcastVersion >= 3: tag = data[readPosition:readPosition+32] else: tag = '' inventoryHash = calculateInventoryHash(data) if inventoryHash in Inventory(): logger.debug('We have already received this broadcast object. Ignoring.') return # It is valid. Let's let our peers know about it. objectType = 3 Inventory()[inventoryHash] = ( objectType, streamNumber, data, embeddedTime, tag) # This object is valid. Forward it to peers. logger.debug('advertising inv with hash: %s', hexlify(inventoryHash)) broadcastToSendDataQueues((streamNumber, 'advertiseobject', inventoryHash)) # Now let's queue it to be processed ourselves. objectProcessorQueue.put((objectType,data)) # If you want to command all of the sendDataThreads to do something, like shutdown or send some data, this # function puts your data into the queues for each of the sendDataThreads. The sendDataThreads are # responsible for putting their queue into (and out of) the sendDataQueues list. def broadcastToSendDataQueues(data): # logger.debug('running broadcastToSendDataQueues') for q in state.sendDataQueues: q.put(data) # sslProtocolVersion if sys.version_info >= (2,7,13): # this means TLSv1 or higher # in the future change to # ssl.PROTOCOL_TLS1.2 sslProtocolVersion = ssl.PROTOCOL_TLS elif sys.version_info >= (2,7,9): # this means any SSL/TLS. SSLv2 and 3 are excluded with an option after context is created sslProtocolVersion = ssl.PROTOCOL_SSLv23 else: # this means TLSv1, there is no way to set "TLSv1 or higher" or # "TLSv1.2" in < 2.7.9 sslProtocolVersion = ssl.PROTOCOL_TLSv1 # ciphers if ssl.OPENSSL_VERSION_NUMBER >= 0x10100000: sslProtocolCiphers = "AECDH-AES256-SHA@SECLEVEL=0" else: sslProtocolCiphers = "AECDH-AES256-SHA"