import os import time import RNS import RNS.vendor.umsgpack as msgpack from .LXMF import APP_NAME class LXMPeer: OFFER_REQUEST_PATH = "/offer" MESSAGE_GET_PATH = "/get" IDLE = 0x00 LINK_ESTABLISHING = 0x01 LINK_READY = 0x02 REQUEST_SENT = 0x03 RESPONSE_RECEIVED = 0x04 RESOURCE_TRANSFERRING = 0x05 ERROR_NO_IDENTITY = 0xf0 ERROR_NO_ACCESS = 0xf1 # Maximum amount of time a peer can # be unreachable before it is removed MAX_UNREACHABLE = 14*24*60*60 # Everytime consecutive time a sync # link fails to establish, add this # amount off time to wait before the # next sync is attempted. SYNC_BACKOFF_STEP = 12*60 # How long to wait for an answer to # peer path requests before deferring # sync to later. PATH_REQUEST_GRACE = 7.5 @staticmethod def from_bytes(peer_bytes, router): dictionary = msgpack.unpackb(peer_bytes) peer = LXMPeer(router, dictionary["destination_hash"]) peer.peering_timebase = dictionary["peering_timebase"] peer.alive = dictionary["alive"] peer.last_heard = dictionary["last_heard"] if "link_establishment_rate" in dictionary: peer.link_establishment_rate = dictionary["link_establishment_rate"] else: peer.link_establishment_rate = 0 if "sync_transfer_rate" in dictionary: peer.sync_transfer_rate = dictionary["sync_transfer_rate"] else: peer.sync_transfer_rate = 0 if "propagation_transfer_limit" in dictionary: try: peer.propagation_transfer_limit = float(dictionary["propagation_transfer_limit"]) except Exception as e: peer.propagation_transfer_limit = None else: peer.propagation_transfer_limit = None for transient_id in dictionary["handled_ids"]: if transient_id in router.propagation_entries: peer.handled_messages.append(transient_id) for transient_id in dictionary["unhandled_ids"]: if transient_id in router.propagation_entries: peer.unhandled_messages.append(transient_id) del dictionary return peer def to_bytes(self): dictionary = {} dictionary["peering_timebase"] = self.peering_timebase dictionary["alive"] = self.alive dictionary["last_heard"] = self.last_heard dictionary["destination_hash"] = self.destination_hash dictionary["link_establishment_rate"] = self.link_establishment_rate dictionary["sync_transfer_rate"] = self.sync_transfer_rate dictionary["propagation_transfer_limit"] = self.propagation_transfer_limit handled_ids = [] for transient_id in self.handled_messages: handled_ids.append(transient_id) unhandled_ids = [] for transient_id in self.unhandled_messages: unhandled_ids.append(transient_id) dictionary["handled_ids"] = handled_ids dictionary["unhandled_ids"] = unhandled_ids return msgpack.packb(dictionary) def __init__(self, router, destination_hash): self.alive = False self.last_heard = 0 self.next_sync_attempt = 0 self.last_sync_attempt = 0 self.sync_backoff = 0 self.peering_timebase = 0 self.link_establishment_rate = 0 self.sync_transfer_rate = 0 self.propagation_transfer_limit = None self.link = None self.state = LXMPeer.IDLE self.unhandled_messages = [] self.handled_messages = [] self.last_offer = [] self.router = router self.destination_hash = destination_hash self.identity = RNS.Identity.recall(destination_hash) if self.identity != None: self.destination = RNS.Destination(self.identity, RNS.Destination.OUT, RNS.Destination.SINGLE, APP_NAME, "propagation") else: self.destination = None RNS.log(f"Could not recall identity for LXMF propagation peer {RNS.prettyhexrep(self.destination_hash)}, will retry identity resolution on next sync", RNS.LOG_WARNING) def sync(self): RNS.log("Initiating LXMF Propagation Node sync with peer "+RNS.prettyhexrep(self.destination_hash), RNS.LOG_DEBUG) self.last_sync_attempt = time.time() if time.time() > self.next_sync_attempt: if not RNS.Transport.has_path(self.destination_hash): RNS.log("No path to peer "+RNS.prettyhexrep(self.destination_hash)+" exists, requesting...", RNS.LOG_DEBUG) RNS.Transport.request_path(self.destination_hash) time.sleep(LXMPeer.PATH_REQUEST_GRACE) if not RNS.Transport.has_path(self.destination_hash): RNS.log("Path request was not answered, retrying sync with peer "+RNS.prettyhexrep(self.destination_hash)+" later", RNS.LOG_DEBUG) else: if self.identity == None: self.identity = RNS.Identity.recall(destination_hash) if self.identity != None: self.destination = RNS.Destination(self.identity, RNS.Destination.OUT, RNS.Destination.SINGLE, APP_NAME, "propagation") if self.destination != None: if len(self.unhandled_messages) > 0: if self.state == LXMPeer.IDLE: RNS.log("Establishing link for sync to peer "+RNS.prettyhexrep(self.destination_hash)+"...", RNS.LOG_DEBUG) self.sync_backoff += LXMPeer.SYNC_BACKOFF_STEP self.next_sync_attempt = time.time() + self.sync_backoff self.link = RNS.Link(self.destination, established_callback = self.link_established, closed_callback = self.link_closed) self.state = LXMPeer.LINK_ESTABLISHING else: if self.state == LXMPeer.LINK_READY: self.alive = True self.last_heard = time.time() self.sync_backoff = 0 RNS.log("Synchronisation link to peer "+RNS.prettyhexrep(self.destination_hash)+" established, preparing request...", RNS.LOG_DEBUG) unhandled_entries = [] unhandled_ids = [] purged_ids = [] for transient_id in self.unhandled_messages: if transient_id in self.router.propagation_entries: unhandled_entry = [ transient_id, self.router.get_weight(transient_id), self.router.get_size(transient_id), ] unhandled_entries.append(unhandled_entry) else: purged_ids.append(transient_id) for transient_id in purged_ids: RNS.log("Dropping unhandled message "+RNS.prettyhexrep(transient_id)+" for peer "+RNS.prettyhexrep(self.destination_hash)+" since it no longer exists in the message store.", RNS.LOG_DEBUG) self.unhandled_messages.remove(transient_id) unhandled_entries.sort(key=lambda e: e[1], reverse=False) per_message_overhead = 16 # Really only 2 bytes, but set a bit higher for now cumulative_size = 24 # Initialised to highest reasonable binary structure overhead for unhandled_entry in unhandled_entries: transient_id = unhandled_entry[0] weight = unhandled_entry[1] lxm_size = unhandled_entry[2] next_size = cumulative_size + (lxm_size+per_message_overhead) if self.propagation_transfer_limit != None and next_size > (self.propagation_transfer_limit*1000): pass else: cumulative_size += (lxm_size+per_message_overhead) unhandled_ids.append(transient_id) RNS.log("Sending sync request to peer "+str(self.destination), RNS.LOG_DEBUG) self.last_offer = unhandled_ids self.link.request(LXMPeer.OFFER_REQUEST_PATH, unhandled_ids, response_callback=self.offer_response, failed_callback=self.request_failed) self.state = LXMPeer.REQUEST_SENT else: RNS.log("Could not request sync to peer "+RNS.prettyhexrep(self.destination_hash)+" since its identity could not be recalled.", RNS.LOG_ERROR) else: RNS.log("Postponing sync with peer "+RNS.prettyhexrep(self.destination_hash)+" for "+RNS.prettytime(self.next_sync_attempt-time.time())+" due to previous failures", RNS.LOG_DEBUG) if self.last_sync_attempt > self.last_heard: self.alive = False def request_failed(self, request_receipt): RNS.log("Sync request to peer "+str(self.destination)+" failed", RNS.LOG_DEBUG) if self.link != None: self.link.teardown() self.state = LXMPeer.IDLE def offer_response(self, request_receipt): try: self.state = LXMPeer.RESPONSE_RECEIVED response = request_receipt.response wanted_messages = [] wanted_message_ids = [] if response == LXMPeer.ERROR_NO_IDENTITY: if self.link != None: RNS.log("Remote peer indicated that no identification was received, retrying...", RNS.LOG_DEBUG) self.link.identify() self.state = LXMPeer.LINK_READY self.sync() elif response == False: # Peer already has all advertised messages for transient_id in self.last_offer: if transient_id in self.unhandled_messages: self.handled_messages.append(transient_id) self.unhandled_messages.remove(transient_id) elif response == True: # Peer wants all advertised messages for transient_id in self.last_offer: wanted_messages.append(self.router.propagation_entries[transient_id]) wanted_message_ids.append(transient_id) else: # Peer wants some advertised messages for transient_id in self.last_offer.copy(): # If the peer did not want the message, it has # already received it from another peer. if not transient_id in response: if transient_id in self.unhandled_messages: self.handled_messages.append(transient_id) self.unhandled_messages.remove(transient_id) for transient_id in response: wanted_messages.append(self.router.propagation_entries[transient_id]) wanted_message_ids.append(transient_id) if len(wanted_messages) > 0: RNS.log("Peer wanted "+str(len(wanted_messages))+" of the available messages", RNS.LOG_DEBUG) lxm_list = [] for message_entry in wanted_messages: file_path = message_entry[1] if os.path.isfile(file_path): file = open(file_path, "rb") lxmf_data = file.read() file.close() lxm_list.append(lxmf_data) data = msgpack.packb([time.time(), lxm_list]) resource = RNS.Resource(data, self.link, callback = self.resource_concluded) resource.transferred_messages = wanted_message_ids resource.sync_transfer_started = time.time() self.state = LXMPeer.RESOURCE_TRANSFERRING else: RNS.log("Peer "+RNS.prettyhexrep(self.destination_hash)+" did not request any of the available messages, sync completed", RNS.LOG_DEBUG) if self.link != None: self.link.teardown() self.link = None self.state = LXMPeer.IDLE except Exception as e: RNS.log("Error while handling offer response from peer "+str(self.destination), RNS.LOG_ERROR) RNS.log("The contained exception was: "+str(e), RNS.LOG_ERROR) if self.link != None: self.link.teardown() self.link = None self.state = LXMPeer.IDLE def resource_concluded(self, resource): if resource.status == RNS.Resource.COMPLETE: for transient_id in resource.transferred_messages: self.handled_messages.append(transient_id) self.unhandled_messages.remove(transient_id) if self.link != None: self.link.teardown() self.link = None self.state = LXMPeer.IDLE rate_str = "" if hasattr(resource, "sync_transfer_started") and resource.sync_transfer_started: self.sync_transfer_rate = (resource.get_transfer_size()*8)/(time.time()-resource.sync_transfer_started) rate_str = f" at {RNS.prettyspeed(self.sync_transfer_rate)}" RNS.log("Sync to peer "+RNS.prettyhexrep(self.destination_hash)+" completed"+rate_str, RNS.LOG_DEBUG) self.alive = True self.last_heard = time.time() else: RNS.log("Resource transfer for LXMF peer sync failed to "+str(self.destination), RNS.LOG_DEBUG) if self.link != None: self.link.teardown() self.link = None self.state = LXMPeer.IDLE def link_established(self, link): self.link.identify(self.router.identity) link_establishment_rate = link.get_establishment_rate() if link_establishment_rate != None: self.link_establishment_rate = link_establishment_rate self.state = LXMPeer.LINK_READY self.next_sync_attempt = 0 self.sync() def link_closed(self, link): self.link = None self.state = LXMPeer.IDLE def handle_message(self, transient_id): if not transient_id in self.handled_messages and not transient_id in self.unhandled_messages: self.unhandled_messages.append(transient_id) def __str__(self): if self.destination_hash: return RNS.prettyhexrep(self.destination_hash) else: return ""