Ejemplo n.º 1
0
    def __init__(self, node, blockchain, process_pool, log):
        self.blockchain = blockchain
        self.node = node
        self.log = log
        self.process_pool = process_pool

        self.requested_blocks = {}

        self.processing_block = False
        self.downloading = False
        self.sending_getblocks = False
        self.blocks_to_process = deque()
        self.getblock_to_send = deque()
        self.items_to_download = deque()
        self.firstrequest = True
        self.blockverifier = BlockVerifier(self.blockchain.database.runmode)
        self.orphanblocks = OrphanBlockPool(log)

        #assert VersionExchangeService is used?
        node.subscribe((VersionExchangeService.EVT_MESSAGE, MSG_INV),
                       self.on_inv)
        node.subscribe((VersionExchangeService.EVT_MESSAGE, MSG_BLOCK),
                       self.on_block)

        self.blockchain.subscribe(Blockchain.EVT_NEW_HIGHEST_BLOCK,
                                  self.on_new_heighest_block)

        self.node.subscribe(VersionExchangeService.EVT_VERSION_EXCHANGED,
                            self.on_version_exchange)
        self.node.subscribe(Node.EVT_DISCONNECTED, self.on_peer_disconnected)
Ejemplo n.º 2
0
    def __init__(self, node, blockchain, process_pool, log):
        self.blockchain = blockchain
        self.node = node
        self.log = log
        self.process_pool = process_pool
        
        self.requested_blocks = {}
        
        self.processing_block = False
        self.downloading = False
        self.sending_getblocks = False
        self.blocks_to_process = deque()
        self.getblock_to_send = deque()
        self.items_to_download = deque()
        self.firstrequest = True
        self.blockverifier = BlockVerifier(self.blockchain.database.runmode)
        self.orphanblocks =  OrphanBlockPool(log)
        
        #assert VersionExchangeService is used?
        node.subscribe((VersionExchangeService.EVT_MESSAGE, MSG_INV), self.on_inv)
        node.subscribe((VersionExchangeService.EVT_MESSAGE, MSG_BLOCK), self.on_block)

        self.blockchain.subscribe (Blockchain.EVT_NEW_HIGHEST_BLOCK, self.on_new_heighest_block)
        
        self.node.subscribe (VersionExchangeService.EVT_VERSION_EXCHANGED, self.on_version_exchange)
        self.node.subscribe (Node.EVT_DISCONNECTED, self.on_peer_disconnected)
Ejemplo n.º 3
0
class BlockchainDownloader():
    # TODO: protect againts hosts that don't respond to GETDATA(timeout => misbehaving)
    # or don't respond to GETBLOCKS(much harder)
    def __init__(self, node, blockchain, process_pool, log):
        self.blockchain = blockchain
        self.node = node
        self.log = log
        self.process_pool = process_pool
        
        self.requested_blocks = {}
        
        self.processing_block = False
        self.downloading = False
        self.sending_getblocks = False
        self.blocks_to_process = deque()
        self.getblock_to_send = deque()
        self.items_to_download = deque()
        self.firstrequest = True
        self.blockverifier = BlockVerifier(self.blockchain.database.runmode)
        self.orphanblocks =  OrphanBlockPool(log)
        
        #assert VersionExchangeService is used?
        node.subscribe((VersionExchangeService.EVT_MESSAGE, MSG_INV), self.on_inv)
        node.subscribe((VersionExchangeService.EVT_MESSAGE, MSG_BLOCK), self.on_block)

        self.blockchain.subscribe (Blockchain.EVT_NEW_HIGHEST_BLOCK, self.on_new_heighest_block)
        
        self.node.subscribe (VersionExchangeService.EVT_VERSION_EXCHANGED, self.on_version_exchange)
        self.node.subscribe (Node.EVT_DISCONNECTED, self.on_peer_disconnected)
    

    #1/keep up with peer heights in version exchanges    
    def on_version_exchange(self, event):
        peer_heigth = event.version_message.start_height
        my_height = self.blockchain.get_height()
        if (peer_heigth > my_height and self.firstrequest):
            self.push_getblocks(event.handler, Uint256.zero())
            self.firstrequest = False

    def on_inv(self, event):
        self.log.debug("on_inv")
        peer, message = event.handler, event.message
        items = []
        for item in message.items:
            if item.type == INV_BLOCK:
                if (self.orphanblocks.contains(item.hash)):
                    #after each geblocks, the other client sends an INV of the highest block 
                    #to continue download
                    self.push_getblocks(peer, item.hash)
                    #push_getblocks(peer, item.hash)
                else:
                    if (not self.blockchain.contains_block(item.hash) and 
                        not item.hash in self.requested_blocks and 
                        not self.is_queued_for_processing(item.hash)):
                        items.append(item)
        if items:
            self.node.send_message(peer, GetdataMessage(items))
            self.log.info("Downloading items: %d block from %s: (%s...)" % 
                      (len([i for i in items if i.type == INV_BLOCK]), 
                       str(peer),
                       ",".join([str(i.hash) for i in items[:5]])))
            for item in items:
                self.requested_blocks[item.hash] = peer
        self.sending_getblocks = False

    def push_getblocks(self, peer, end_hash):
        self.getblock_to_send.append((peer, end_hash))
        if not self.processing_block:
            self._process_getblocks()
                    
    def _process_getblocks(self):
        self.sending_getblocks = True
        peer, end_hash = self.getblock_to_send.popleft()
        locator = self.blockchain.get_block_locator()
        self.log.info("requesting blocks from %s, block locator: %s" % (str(peer), str(locator)))
        request = GetblocksMessage(locator, end_hash)
        self.node.send_message(peer, request)
    
    def is_queued_for_processing(self, blkhash):
        for peer, h, blk in self.blocks_to_process:
            if h == blkhash:
                return True
        return False
        
    def on_block(self, event):
        peer, message = event.handler, event.message
        hash = hash_block(message.block)
        self.log.debug("on_block : %s" % (str(hash)))
        if (hash not in self.requested_blocks):
            self.misbehaving(peer, "peer sending unrequest 'block' : %s" % hash)
            return
        del self.requested_blocks[hash]
        if not self.requested_blocks:
            self.downloading = False
        self.blocks_to_process.append( (peer, hash, message.block))
        self.start_processing()

    def on_missing_block(self, event):
        if not self.getblock_to_send and not self.sending_getblocks:
            self.push_getblocks(event.peer, event.missing_hash)
    
    def start_processing(self):
        if not self.processing_block:
            self.log.debug("start_processing")
            self.processing_block = True
            self._process_blocks()
    
    def on_new_heighest_block(self, event):
        # relay blocks to peers
        for p in self.node.version_service.version_exchanged_nodes:
            if event.height > self.node.version_service.version_statuses[p].version_message.start_height - 2000:
                self.node.send_message(p, InvMessage([Invitem(INV_BLOCK, event.blkhash)]))

    @asynch_method
    def _process_blocks(self):
        while self.blocks_to_process:
            peer, hash, block = self.blocks_to_process.popleft()
            self.log.debug("processing block : %s" % (hash))
            try:
                yield self.accept_block(peer, hash, block)
            except Exception as e:
                traceback.print_exc()
                print e
                self.log.error(traceback.format_exc())
                self.misbehaving(peer, str(e))
                return
        self.processing_block = False
        self.log.debug("end_processing")
            
        if self.items_to_download:
            self._download_items()
        if self.getblock_to_send:
            self._process_getblocks()
    
    def misbehaving(self, peer, reason):
        self.cleanup_peer_tasks(peer)
        self.node.misbehaving(peer, reason)

    def cleanup_peer_tasks(self, peer):
        self.blocks_to_process = deque(filter(lambda (p, hash, blk): p != peer, self.blocks_to_process))
        self.getblock_to_send = deque(filter(lambda (p, end_hash): p != peer, self.getblock_to_send))        
        self.items_to_download = deque(filter(lambda (p, items): p != peer, self.items_to_download))   
        req_blocks = [blkhash for blkhash, p in self.requested_blocks.iteritems() if p == peer]
        for blkhash in req_blocks:
            del self.requested_blocks[blkhash]
        
    def on_peer_disconnected(self, event):
        self.cleanup_peer_tasks(event.handler)
 
    @asynch_method
    def accept_block(self, sender, hash, block):
        if hash in self.orphanblocks or self.blockchain.contains_block(hash):
            raise Exception("Block allready added : %s" % (str(hash)))
        #Checks-1 (done before finding the parent block) (main.cpp:1392)
        self.blockverifier.basic_checks(hash, block)
        #Find parent block in blockchain or declare orphan.
        if (not self.blockchain.contains_block(block.blockheader.hash_prev)):
            #Add to orphan blockpool
            self.log.info("Adding ophan block: %s" % (str( hash)))
            self.orphanblocks.add_block(sender, hash, block)
            sender, missing_hash = self.orphanblocks.get_orphan_root(hash)
            #request missing blocks from this peer
            if not self.getblock_to_send and not self.sending_getblocks:
                self.push_getblocks(sender, missing_hash)
            return
        #TODO: Check timestamp
        #if (GetBlockTime() > GetAdjustedTime() + 2 * 60 * 60)
        #return error("CheckBlock() : block timestamp too far in the future");     
        block_handle = yield self.add_to_blockchain(hash, block)
        added_block_handles = [block_handle]
        #recursively process any orphan blocks that depended on this one
        descendent_blocks = self.orphanblocks.pop_descendant_blocks(hash)
        for sender, blkhash, block in descendent_blocks:
            block_handle = yield self.add_to_blockchain(blkhash, block)
            added_block_handles.append(block_handle)
        yield added_block_handles

    @asynch_method
    def add_to_blockchain(self, blkhash, block):
        #Checks-2 (done after finding the parent block)
        #self.blockverifier.accept_block(blkhash, block, self.blockchain)
        yield self.blockchain.append_block(blkhash, block, self.process_pool)
        
Ejemplo n.º 4
0
class BlockchainDownloader():
    # TODO: protect againts hosts that don't respond to GETDATA(timeout => misbehaving)
    # or don't respond to GETBLOCKS(much harder)
    def __init__(self, node, blockchain, process_pool, log):
        self.blockchain = blockchain
        self.node = node
        self.log = log
        self.process_pool = process_pool

        self.requested_blocks = {}

        self.processing_block = False
        self.downloading = False
        self.sending_getblocks = False
        self.blocks_to_process = deque()
        self.getblock_to_send = deque()
        self.items_to_download = deque()
        self.firstrequest = True
        self.blockverifier = BlockVerifier(self.blockchain.database.runmode)
        self.orphanblocks = OrphanBlockPool(log)

        #assert VersionExchangeService is used?
        node.subscribe((VersionExchangeService.EVT_MESSAGE, MSG_INV),
                       self.on_inv)
        node.subscribe((VersionExchangeService.EVT_MESSAGE, MSG_BLOCK),
                       self.on_block)

        self.blockchain.subscribe(Blockchain.EVT_NEW_HIGHEST_BLOCK,
                                  self.on_new_heighest_block)

        self.node.subscribe(VersionExchangeService.EVT_VERSION_EXCHANGED,
                            self.on_version_exchange)
        self.node.subscribe(Node.EVT_DISCONNECTED, self.on_peer_disconnected)

    #1/keep up with peer heights in version exchanges
    def on_version_exchange(self, event):
        peer_heigth = event.version_message.start_height
        my_height = self.blockchain.get_height()
        if (peer_heigth > my_height and self.firstrequest):
            self.push_getblocks(event.handler, Uint256.zero())
            self.firstrequest = False

    def on_inv(self, event):
        self.log.debug("on_inv")
        peer, message = event.handler, event.message
        items = []
        for item in message.items:
            if item.type == INV_BLOCK:
                if (self.orphanblocks.contains(item.hash)):
                    #after each geblocks, the other client sends an INV of the highest block
                    #to continue download
                    self.push_getblocks(peer, item.hash)
                    #push_getblocks(peer, item.hash)
                else:
                    if (not self.blockchain.contains_block(item.hash)
                            and not item.hash in self.requested_blocks
                            and not self.is_queued_for_processing(item.hash)):
                        items.append(item)
        if items:
            self.node.send_message(peer, GetdataMessage(items))
            self.log.info(
                "Downloading items: %d block from %s: (%s...)" %
                (len([i for i in items if i.type == INV_BLOCK
                      ]), str(peer), ",".join([str(i.hash)
                                               for i in items[:5]])))
            for item in items:
                self.requested_blocks[item.hash] = peer
        self.sending_getblocks = False

    def push_getblocks(self, peer, end_hash):
        self.getblock_to_send.append((peer, end_hash))
        if not self.processing_block:
            self._process_getblocks()

    def _process_getblocks(self):
        self.sending_getblocks = True
        peer, end_hash = self.getblock_to_send.popleft()
        locator = self.blockchain.get_block_locator()
        self.log.info("requesting blocks from %s, block locator: %s" %
                      (str(peer), str(locator)))
        request = GetblocksMessage(locator, end_hash)
        self.node.send_message(peer, request)

    def is_queued_for_processing(self, blkhash):
        for peer, h, blk in self.blocks_to_process:
            if h == blkhash:
                return True
        return False

    def on_block(self, event):
        peer, message = event.handler, event.message
        hash = hash_block(message.block)
        self.log.debug("on_block : %s" % (str(hash)))
        if (hash not in self.requested_blocks):
            self.misbehaving(peer,
                             "peer sending unrequest 'block' : %s" % hash)
            return
        del self.requested_blocks[hash]
        if not self.requested_blocks:
            self.downloading = False
        self.blocks_to_process.append((peer, hash, message.block))
        self.start_processing()

    def on_missing_block(self, event):
        if not self.getblock_to_send and not self.sending_getblocks:
            self.push_getblocks(event.peer, event.missing_hash)

    def start_processing(self):
        if not self.processing_block:
            self.log.debug("start_processing")
            self.processing_block = True
            self._process_blocks()

    def on_new_heighest_block(self, event):
        # relay blocks to peers
        for p in self.node.version_service.version_exchanged_nodes:
            if event.height > self.node.version_service.version_statuses[
                    p].version_message.start_height - 2000:
                self.node.send_message(
                    p, InvMessage([Invitem(INV_BLOCK, event.blkhash)]))

    @asynch_method
    def _process_blocks(self):
        while self.blocks_to_process:
            peer, hash, block = self.blocks_to_process.popleft()
            self.log.debug("processing block : %s" % (hash))
            try:
                yield self.accept_block(peer, hash, block)
            except Exception as e:
                traceback.print_exc()
                print e
                self.log.error(traceback.format_exc())
                self.misbehaving(peer, str(e))
                return
        self.processing_block = False
        self.log.debug("end_processing")

        if self.items_to_download:
            self._download_items()
        if self.getblock_to_send:
            self._process_getblocks()

    def misbehaving(self, peer, reason):
        self.cleanup_peer_tasks(peer)
        self.node.misbehaving(peer, reason)

    def cleanup_peer_tasks(self, peer):
        self.blocks_to_process = deque(
            filter(lambda (p, hash, blk): p != peer, self.blocks_to_process))
        self.getblock_to_send = deque(
            filter(lambda (p, end_hash): p != peer, self.getblock_to_send))
        self.items_to_download = deque(
            filter(lambda (p, items): p != peer, self.items_to_download))
        req_blocks = [
            blkhash for blkhash, p in self.requested_blocks.iteritems()
            if p == peer
        ]
        for blkhash in req_blocks:
            del self.requested_blocks[blkhash]

    def on_peer_disconnected(self, event):
        self.cleanup_peer_tasks(event.handler)

    @asynch_method
    def accept_block(self, sender, hash, block):
        if hash in self.orphanblocks or self.blockchain.contains_block(hash):
            raise Exception("Block allready added : %s" % (str(hash)))
        #Checks-1 (done before finding the parent block) (main.cpp:1392)
        self.blockverifier.basic_checks(hash, block)
        #Find parent block in blockchain or declare orphan.
        if (not self.blockchain.contains_block(block.blockheader.hash_prev)):
            #Add to orphan blockpool
            self.log.info("Adding ophan block: %s" % (str(hash)))
            self.orphanblocks.add_block(sender, hash, block)
            sender, missing_hash = self.orphanblocks.get_orphan_root(hash)
            #request missing blocks from this peer
            if not self.getblock_to_send and not self.sending_getblocks:
                self.push_getblocks(sender, missing_hash)
            return
        #TODO: Check timestamp
        #if (GetBlockTime() > GetAdjustedTime() + 2 * 60 * 60)
        #return error("CheckBlock() : block timestamp too far in the future");
        block_handle = yield self.add_to_blockchain(hash, block)
        added_block_handles = [block_handle]
        #recursively process any orphan blocks that depended on this one
        descendent_blocks = self.orphanblocks.pop_descendant_blocks(hash)
        for sender, blkhash, block in descendent_blocks:
            block_handle = yield self.add_to_blockchain(blkhash, block)
            added_block_handles.append(block_handle)
        yield added_block_handles

    @asynch_method
    def add_to_blockchain(self, blkhash, block):
        #Checks-2 (done after finding the parent block)
        #self.blockverifier.accept_block(blkhash, block, self.blockchain)
        yield self.blockchain.append_block(blkhash, block, self.process_pool)