Implemented dandelion stemout stream building

This commit is contained in:
Kevin F 2022-03-14 10:04:28 -05:00
parent 9bf16c5758
commit 6c2b1e49a2
3 changed files with 49 additions and 15 deletions

View File

@ -1,16 +1,16 @@
from queue import Queue
from threading import Thread, Timer
from time import sleep
from secrets import choice
import traceback
from asyncio import wait_for
from typing import TYPE_CHECKING, Tuple, List, Set
from typing import TYPE_CHECKING, Coroutine, Tuple, List
from onionrthreads import add_delayed_thread
from blockdb import add_block_to_db
import logger
from ..constants import BLACKHOLE_EVADE_TIMER_SECS, MAX_OUTBOUND_DANDELION_EDGE
from ..constants import BLACKHOLE_EVADE_TIMER_SECS, OUTBOUND_DANDELION_EDGES
from ..commands import GossipCommands, command_to_byte
from .. import dandelion
@ -33,11 +33,20 @@ async def _setup_edge(
peer: 'Peer' = choice(peer_set - exclude_set)
except IndexError:
raise NotEnoughEdges
async def _get_sock():
return peer.get_socket()
# If peer is good or bad, exclude it no matter what
exclude_set.add(peer)
try:
s = peer.get_socket()
s = await wait_for(_get_sock(), 12)
except TimeoutError:
logger.debug(f"{peer.transport_address} timed out when trying stemout")
except Exception:
logger.debug(traceback.format_exc())
exclude_set.add(peer)
return
try:
s.sendall(command_to_byte(GossipCommands.PUT_BLOCKS))
@ -54,9 +63,7 @@ async def _setup_edge(
else:
# Return peer socket if it is in stem reception mode successfully
return s
finally:
# If peer is good or bad, exclude it no matter what
exclude_set.add(peer)
# If they won't accept stem blocks, close the socket
s.close()
@ -73,7 +80,6 @@ async def stem_out(
peer_set: OrderedSet['Peer'],
d_phase: 'DandelionPhase'):
# don't bother if there are no possible outbound edges
if not len(peer_set):
sleep(1)
@ -87,22 +93,49 @@ async def stem_out(
BLACKHOLE_EVADE_TIMER_SECS, list(block_q.queue))
peer_sockets: List['socket.socket'] = []
stream_routines: List[Coroutine] = []
# Pick edges randomly
# Using orderedset for the tried edges to ensure random pairing with queue
tried_edges: OrderedSet['Peer'] = OrderedSet()
while len(peer_sockets) < MAX_OUTBOUND_DANDELION_EDGE:
while len(peer_sockets) < OUTBOUND_DANDELION_EDGES:
try:
peer_sockets.append(_setup_edge(peer_set, tried_edges))
# Get a socket for stem out (makes sure they accept)
peer_sockets.append(
await wait_for(_setup_edge(peer_set, tried_edges), 15))
except NotEnoughEdges:
logger.debug("Not able to build enough peers for stemout")
# No possible edges at this point (edges < OUTBOUND_DANDELION_EDGE)
logger.warn("Not able to build enough peers for stemout.", terminal=True)
break
finally:
else:
# Ran out of time for stem phase
if not d_phase.is_stem_phase() or d_phase.remaining_time() < 5:
logger.error(
"Did not stem out any blocks in time, " +
"if this happens regularly you may be under attack",
terminal=True)
list(map(lambda p: p.close(), peer_sockets))
peer_sockets.clear()
break
# If above loop ran out of time or NotEnoughEdges, loops below will not execute
for count, peer_socket in enumerate(peer_sockets):
stream_routines.append(
_do_stem_stream(peer_socket, block_queues[count], d_phase))
for routine in stream_routines:
try:
await wait_for(routine, d_phase.remaining_time() + 1)
except TimeoutError:
# This is what should happen if everything went well
pass
except Exception:
logger.warn(traceback.format_exc())
else:
# stream routine exited early
pass
# Clean up stem sockets
for sock in peer_sockets:
sock.close()

View File

@ -3,13 +3,13 @@ PEER_AMOUNT_TO_ASK = 3
TRANSPORT_SIZE_BYTES = 64
BLOCK_MAX_SIZE = 1024 * 2000
BLOCK_ID_SIZE = 128
DANDELION_EPOCH_LENGTH = 60
DANDELION_EPOCH_LENGTH = 120
# Magic number i made up, not really specified in dandelion++ paper
MAX_INBOUND_DANDELION_EDGE = 50 # Mainly picked to avoid slowloris
# Dandelion subgraph is aprox 4-regular
MAX_OUTBOUND_DANDELION_EDGE = 2
OUTBOUND_DANDELION_EDGES = 2
MAX_STEM_BLOCKS_PER_STREAM = 1000
BLACKHOLE_EVADE_TIMER_SECS = DANDELION_EPOCH_LENGTH * 3

View File

@ -13,6 +13,7 @@ class TorPeer:
def get_socket(self) -> socks.socksocket:
s = socks.socksocket()
s.set_proxy(socks.SOCKS4, self.socks_host, self.socks_port, rdns=True)
s.settimeout(60)
s.connect((self.onion_address, 80))
return s