Work on stemout

src/blockdb/__init__.py

@@ -6,7 +6,7 @@ from utils import identifyhome
 block_db_path = identifyhome.identify_home() + 'blockdata'
 
 
-def store_vdf_block(block: Block):
+def add_block_to_db(block: Block):
     db.set(block_db_path, block.id, block.raw)
 
 

src/gossip/client/__init__.py

@@ -26,7 +26,7 @@ import onionrplugins
 from ..commands import GossipCommands
 from gossip.dandelion.phase import DandelionPhase
 from onionrthreads import add_onionr_thread
-from blockdb import store_vdf_block
+from blockdb import add_block_to_db
 
 
 from .announce import do_announce
@@ -51,7 +51,7 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 def gossip_client(
         peer_set: OrderedSet['Peer'],
-        block_queues: Tuple[Queue['Block']],
+        block_queues: Tuple[Queue['Block'], Queue['Block']],
         dandelion_seed: bytes):
     """
     Gossip client does the following:

src/gossip/client/dandelionstem.py

@@ -1,7 +1,16 @@
 from queue import Queue
+from threading import Timer
 from time import sleep
+from secrets import choice
+import traceback
 
-from typing import TYPE_CHECKING, Tuple
+from typing import TYPE_CHECKING, Tuple, List, Set
+
+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
 
 if TYPE_CHECKING:
     from ordered_set import OrderedSet
@@ -9,15 +18,45 @@ if TYPE_CHECKING:
     from ..peer import Peer
     from ..dandelion.phase import DandelionPhase
 
+
+class NotEnoughEdges(ValueError): pass  # noqa
+
+
+def _setup_edge(
+        peer_set: OrderedSet['Peer'], exclude_set: OrderedSet['Peer']):
+    """Negotiate stem connection with random peer, add to exclude set if fail"""
+    try:
+        peer: 'Peer' = choice(peer_set - exclude_set)
+    except IndexError:
+        raise NotEnoughEdges
+    try:
+        s = peer.get_socket()
+    except Exception:
+        logger.debug(traceback.format_exc())
+        exclude_set.add(peer)
+
+
+
 def stem_out(
-        block_queues: Tuple[Queue['Block']],
+        block_queues: Tuple[Queue['Block'], Queue['Block']],
         peer_set: OrderedSet['Peer'],
         d_phase: 'DandelionPhase'):
 
-    # Spawn a thread with block set to add to db after time for black hole attack
+    # Spawn threads with deep copied block queue to add to db after time
+    # for black hole attack
+    for block_q in block_queues:
+        add_delayed_thread(
+            lambda q: set(map(add_block_to_db, q)),
+            BLACKHOLE_EVADE_TIMER_SECS, list(block_q.queue))
 
+    # don't bother if there are no possible outbound edges
     if not len(peer_set):
         sleep(1)
         return
 
+    # Pick edges randomly
+    # Using orderedset for the tried edges to ensure random pairing with queue
+    tried_edges: OrderedSet['Peer'] = OrderedSet()
+
+
 

src/gossip/client/storeblocks.py

@@ -10,7 +10,7 @@ if TYPE_CHECKING:
 
 
 def store_blocks(
-        block_queues: Tuple[Queue['Block']],
+        block_queues: Tuple[Queue['Block'], Queue['Block']],
         dandelion_phase: 'DandelionPhase'):
 
     new_queue: Queue['Block'] = Queue()
@@ -31,7 +31,7 @@ def store_blocks(
     while not dandelion_phase.is_stem_phase() \
             and dandelion_phase.remaining_time() > 1:
         try:
-            blockdb.store_vdf_block(
+            blockdb.add_block_to_db(
                 new_queue.get(timeout=dandelion_phase.remaining_time())
             )
         except TimeoutError:

src/gossip/constants.py

@@ -4,5 +4,12 @@ TRANSPORT_SIZE_BYTES = 64
 BLOCK_MAX_SIZE = 1024 * 2000
 BLOCK_ID_SIZE = 128
 DANDELION_EPOCH_LENGTH = 60
-MAX_INBOUND_DANDELION_EDGE = 2
+
-MAX_STEM_BLOCKS_PER_STREAM = 1000
+# Magic number i made up, not really specified in dandelion++ paper
+MAX_INBOUND_DANDELION_EDGE = 50  # Mainly picked to avoid slowlorisstor browser dvm 16
+
+# Dandelion subgraph is aprox 4-regular
+MAX_OUTBOUND_DANDELION_EDGE = 2
+
+MAX_STEM_BLOCKS_PER_STREAM = 1000
+BLACKHOLE_EVADE_TIMER_SECS = DANDELION_EPOCH_LENGTH * 3

src/gossip/server/__init__.py

@@ -40,7 +40,7 @@ inbound_dandelion_edge_count = [0]
 
 def gossip_server(
         peer_set: OrderedSet['Peer'],
-        block_queues: Tuple[Queue['Block']],
+        block_queues: Tuple[Queue['Block'], Queue['Block']],
         dandelion_seed: bytes):
 
     async def peer_connected(

src/gossip/server/acceptstem.py

@@ -20,7 +20,7 @@ if TYPE_CHECKING:
 
 
 async def accept_stem_blocks(
-        block_queues: Tuple[Queue['Block']],
+        block_queues: Tuple[Queue['Block'], Queue['Block']],
         reader: 'StreamReader',
         writer: 'StreamWriter',
         inbound_edge_count: List[int]):
@@ -35,6 +35,8 @@ async def accept_stem_blocks(
     read_routine = reader.read(BLOCK_ID_SIZE)
     stream_start_time = int(time())
 
+    block_queue_to_use = secrets.choice(block_queues)
+
     for _ in range(MAX_STEM_BLOCKS_PER_STREAM):
         block_id = (
             await wait_for(read_routine, base_wait_timeout)).decode('utf-8')
@@ -51,7 +53,7 @@ async def accept_stem_blocks(
         raw_block: bytes = await wait_for(
             reader.read(block_size), base_wait_timeout * 6)
 
-        secrets.choice(block_queues).put(
+        block_queue_to_use.put(
             Block(block_id, raw_block, auto_verify=True)
         )
         # Regardless of stem phase, we add to queue

src/onionrthreads/__init__.py

@@ -4,7 +4,6 @@ from typing import Iterable
 import traceback
 from threading import Thread
 from uuid import uuid4
-
 from time import sleep
 
 import logger
@@ -42,3 +41,10 @@ def add_onionr_thread(
                 *args),
            kwargs=kwargs,
            daemon=True).start()
+
+
+def add_delayed_thread(func: Callable, sleep_secs: int, *args, **kwargs):
+    assert sleep_secs > 0
+    t = Thread(target=func, args=args, kwargs=kwargs, daemon=True)
+    sleep(sleep_secs)
+    t.start()