Implemented unknown path discovery

This commit is contained in:
Mark Qvist 2022-05-22 14:18:58 +02:00
parent 81b92ffdc1
commit f3ff71d9b8
3 changed files with 94 additions and 9 deletions

View File

@ -40,8 +40,8 @@ class Interface:
MODE_GATEWAY = 0x06
# Which interface modes a Transport Node
# must act as path request agent for.
PATH_REQUEST_AGENT_FOR = [MODE_ACCESS_POINT, MODE_GATEWAY]
# should actively discover paths for.
DISCOVER_PATHS_FOR = [MODE_ACCESS_POINT, MODE_GATEWAY]
def __init__(self):
self.rxb = 0

View File

@ -64,6 +64,7 @@ class Transport:
# various situations
LOCAL_REBROADCASTS_MAX = 2 # How many local rebroadcasts of an announce is allowed
PATH_REQUEST_TIMEOUT = 15 # Default timuout for client path requests in seconds
PATH_REQUEST_GRACE = 0.35 # Grace time before a path announcement is made, allows directly reachable peers to respond first
PATH_REQUEST_RW = 2 # Path request random window
@ -93,6 +94,8 @@ class Transport:
tunnels = {} # A table storing tunnels to other transport instances
announce_rate_table = {} # A table for keeping track of announce rates
discovery_path_requests = {} # A table for keeping track of path requests on behalf of other nodes
# Transport control destinations are used
# for control purposes like path requests
control_destinations = []
@ -279,6 +282,10 @@ class Transport:
def jobs():
outgoing = []
Transport.jobs_running = True
# TODO: Remove at some point
# start_time = time.time()
try:
if not Transport.jobs_locked:
# Process receipts list for timed-out packets
@ -384,6 +391,15 @@ class Transport:
stale_paths.append(destination_hash)
RNS.log("Path to "+RNS.prettyhexrep(destination_hash)+" was removed since the attached interface no longer exists", RNS.LOG_DEBUG)
# Cull the pending discovery path requests table
stale_discovery_path_requests = []
for destination_hash in Transport.discovery_path_requests:
entry = Transport.discovery_path_requests[destination_hash]
if time.time() > entry["timeout"]:
stale_discovery_path_requests.append(destination_hash)
RNS.log("Waiting path request for "+RNS.prettyhexrep(destination_hash)+" timed out and was removed", RNS.LOG_DEBUG)
# Cull the tunnel table
stale_tunnels = []
ti = 0
@ -452,6 +468,17 @@ class Transport:
else:
RNS.log("Removed "+str(i)+" paths", RNS.LOG_EXTREME)
i = 0
for destination_hash in stale_discovery_path_requests:
Transport.discovery_path_requests.pop(destination_hash)
i += 1
if i > 0:
if i == 1:
RNS.log("Removed "+str(i)+" waiting path request", RNS.LOG_EXTREME)
else:
RNS.log("Removed "+str(i)+" waiting path requests", RNS.LOG_EXTREME)
i = 0
for tunnel_id in stale_tunnels:
Transport.tunnels.pop(tunnel_id)
@ -472,6 +499,13 @@ class Transport:
Transport.jobs_running = False
# TODO: Remove at some point
# end_time = time.time()
# if RNS.loglevel >= RNS.LOG_EXTREME:
# duration = round((end_time - start_time) * 1000, 2)
# if duration > 1:
# RNS.log("Transport jobs took "+str(duration)+"ms", RNS.LOG_EXTREME)
for packet in outgoing:
packet.send()
@ -1207,6 +1241,7 @@ class Transport:
announce_context = RNS.Packet.NONE
announce_data = packet.data
# TODO: Shouldn't the context be PATH_RESPONSE in the first case here?
if Transport.from_local_client(packet) and packet.context == RNS.Packet.PATH_RESPONSE:
for local_interface in Transport.local_client_interfaces:
if packet.receiving_interface != local_interface:
@ -1241,6 +1276,38 @@ class Transport:
new_announce.hops = packet.hops
new_announce.send()
# If we have any waiting discovery path requests
# for this destination, we retransmit to that
# interface immediately
if packet.destination_hash in Transport.discovery_path_requests:
pr_entry = Transport.discovery_path_requests[packet.destination_hash]
attached_interface = pr_entry["requesting_interface"]
interface_str = " on "+str(attached_interface)
RNS.log("Got matching announce, answering waiting discovery path request for "+RNS.prettyhexrep(packet.destination_hash)+interface_str, RNS.LOG_DEBUG)
announce_identity = RNS.Identity.recall(packet.destination_hash)
announce_destination = RNS.Destination(announce_identity, RNS.Destination.OUT, RNS.Destination.SINGLE, "unknown", "unknown");
announce_destination.hash = packet.destination_hash
announce_destination.hexhash = announce_destination.hash.hex()
announce_context = RNS.Packet.NONE
announce_data = packet.data
new_announce = RNS.Packet(
announce_destination,
announce_data,
RNS.Packet.ANNOUNCE,
context = RNS.Packet.PATH_RESPONSE,
header_type = RNS.Packet.HEADER_2,
transport_type = Transport.TRANSPORT,
transport_id = Transport.identity.hash,
attached_interface = attached_interface
)
new_announce.hops = packet.hops
new_announce.send()
destination_table_entry = [now, received_from, announce_hops, expires, random_blobs, packet.receiving_interface, packet]
Transport.destination_table[packet.destination_hash] = destination_table_entry
RNS.log("Destination "+RNS.prettyhexrep(packet.destination_hash)+" is now "+str(announce_hops)+" hops away via "+RNS.prettyhexrep(received_from)+" on "+str(packet.receiving_interface), RNS.LOG_DEBUG)
@ -1323,7 +1390,7 @@ class Transport:
if packet.receiving_interface == link_entry[2]:
# TODO: Should we validate the LR proof at each transport
# step before transporting it?
RNS.log("Link request proof received on correct interface, transporting it via "+str(link_entry[4]), RNS.LOG_DEBUG)
# RNS.log("Link request proof received on correct interface, transporting it via "+str(link_entry[4]), RNS.LOG_EXTREME)
new_raw = packet.raw[0:1]
new_raw += struct.pack("!B", packet.hops)
new_raw += packet.raw[2:]
@ -1730,13 +1797,17 @@ class Transport:
@staticmethod
def path_request(destination_hash, is_from_local_client, attached_interface, requestor_transport_id=None):
should_search_for_unknown = False
if attached_interface != None:
if RNS.Reticulum.transport_enabled() and attached_interface.mode in RNS.Interfaces.Interface.Interface.DISCOVER_PATHS_FOR:
should_search_for_unknown = True
interface_str = " on "+str(attached_interface)
else:
interface_str = ""
# TODO: Clean
# RNS.log("Path request for "+RNS.prettyhexrep(destination_hash)+interface_str, RNS.LOG_DEBUG)
RNS.log("Path request for "+RNS.prettyhexrep(destination_hash)+interface_str, RNS.LOG_DEBUG)
destination_exists_on_local_client = False
if len(Transport.local_client_interfaces) > 0:
@ -1764,7 +1835,7 @@ class Transport:
# path requests with transport instance keys is quite
# inefficient. There is probably a better way. Doing
# path invalidation here would decrease the network
# convergence time.
# convergence time. Maybe just drop it?
RNS.log("Not answering path request for "+RNS.prettyhexrep(destination_hash)+interface_str+", since next hop is the requestor", RNS.LOG_DEBUG)
else:
RNS.log("Answering path request for "+RNS.prettyhexrep(destination_hash)+interface_str+", path is known", RNS.LOG_DEBUG)
@ -1801,6 +1872,20 @@ class Transport:
if not interface == attached_interface:
Transport.request_path(destination_hash, interface)
elif should_search_for_unknown:
if destination_hash in Transport.discovery_path_requests:
RNS.log("There is already a waiting path request for "+RNS.prettyhexrep(destination_hash)+" on behalf of path request"+interface_str, RNS.LOG_DEBUG)
else:
# Forward path request on all interfaces
# except the requestor interface
RNS.log("Attempting to discover unknown path to "+RNS.prettyhexrep(destination_hash)+" on behalf of path request"+interface_str, RNS.LOG_DEBUG)
pr_entry = { "destination_hash": destination_hash, "timeout": time.time()+Transport.PATH_REQUEST_TIMEOUT, "requesting_interface": attached_interface }
Transport.discovery_path_requests[destination_hash] = pr_entry
for interface in Transport.interfaces:
if not interface == attached_interface:
Transport.request_path(destination_hash, interface)
elif not is_from_local_client and len(Transport.local_client_interfaces) > 0:
# Forward the path request on all local
# client interfaces

View File

@ -257,7 +257,7 @@ def main():
metavar="seconds",
type=float,
help="timeout before giving up",
default=15
default=RNS.Transport.PATH_REQUEST_TIMEOUT
)
parser.add_argument(