Added reverse path detection

This commit is contained in:
Mark Qvist 2022-04-20 19:29:25 +02:00
parent 4af14a712c
commit 0db64610b1
3 changed files with 64 additions and 42 deletions

View File

@ -207,11 +207,12 @@ class Identity:
del announced_identity
if hasattr(packet, "transport_id") and packet.transport_id != None:
RNS.log("Valid announce for "+RNS.prettyhexrep(destination_hash)+" received via "+RNS.prettyhexrep(packet.transport_id)+" on "+str(packet.receiving_interface), RNS.LOG_EXTREME)
RNS.log("Valid announce for "+RNS.prettyhexrep(destination_hash)+" "+str(packet.hops)+" hops away, received via "+RNS.prettyhexrep(packet.transport_id)+" on "+str(packet.receiving_interface), RNS.LOG_EXTREME)
else:
RNS.log("Valid announce for "+RNS.prettyhexrep(destination_hash)+" received on "+str(packet.receiving_interface), RNS.LOG_EXTREME)
RNS.log("Valid announce for "+RNS.prettyhexrep(destination_hash)+" "+str(packet.hops)+" hops away, received on "+str(packet.receiving_interface), RNS.LOG_EXTREME)
return True
else:
RNS.log("Received invalid announce for "+RNS.prettyhexrep(destination_hash), RNS.LOG_DEBUG)
del announced_identity

View File

@ -961,7 +961,7 @@ class Transport:
break
if (now >= path_expires):
# We also check that the announce hash is
# We also check that the announce is
# different from ones we've already heard,
# to avoid loops in the network
if not random_blob in random_blobs:
@ -1532,40 +1532,51 @@ class Transport:
return False
@staticmethod
def request_path(destination_hash):
def request_path(destination_hash, on_interface=None):
"""
Requests a path to the destination from the network. If
another reachable peer on the network knows a path, it
will announce it.
:param destination_hash: A destination hash as *bytes*.
:param on_interface: If specified, the path request will only be sent on this interface. In normal use, Reticulum handles this automatically, and this parameter should not be used.
"""
path_request_data = destination_hash + RNS.Identity.get_random_hash()
path_request_dst = RNS.Destination(None, RNS.Destination.OUT, RNS.Destination.PLAIN, Transport.APP_NAME, "path", "request")
packet = RNS.Packet(path_request_dst, path_request_data, packet_type = RNS.Packet.DATA, transport_type = RNS.Transport.BROADCAST, header_type = RNS.Packet.HEADER_1)
packet.send()
if RNS.Reticulum.transport_enabled():
path_request_data = destination_hash+Transport.identity.hash+RNS.Identity.get_random_hash()
else:
path_request_data = destination_hash+RNS.Identity.get_random_hash()
@staticmethod
def request_path_on_interface(destination_hash, interface):
path_request_data = destination_hash + RNS.Identity.get_random_hash()
path_request_dst = RNS.Destination(None, RNS.Destination.OUT, RNS.Destination.PLAIN, Transport.APP_NAME, "path", "request")
packet = RNS.Packet(path_request_dst, path_request_data, packet_type = RNS.Packet.DATA, transport_type = RNS.Transport.BROADCAST, header_type = RNS.Packet.HEADER_1, attached_interface = interface)
packet = RNS.Packet(path_request_dst, path_request_data, packet_type = RNS.Packet.DATA, transport_type = RNS.Transport.BROADCAST, header_type = RNS.Packet.HEADER_1, attached_interface = on_interface)
packet.send()
@staticmethod
def path_request_handler(data, packet):
try:
# If there is at least bytes enough for a destination
# hash in the packet, we assume those bytes are the
# destination being requested.
if len(data) >= RNS.Identity.TRUNCATED_HASHLENGTH//8:
# If there is also enough bytes for a trasport
# instance ID and at least one random byte, we
# assume the next bytes to be the trasport ID
# of the requesting transport instance.
if len(data) > (RNS.Identity.TRUNCATED_HASHLENGTH//8)*2:
requesting_transport_instance = data[RNS.Identity.TRUNCATED_HASHLENGTH//8:(RNS.Identity.TRUNCATED_HASHLENGTH//8)*2]
else:
requesting_transport_instance = None
Transport.path_request(
data[:RNS.Identity.TRUNCATED_HASHLENGTH//8],
Transport.from_local_client(packet),
packet.receiving_interface
packet.receiving_interface,
requesting_transport_instance,
)
except Exception as e:
RNS.log("Error while handling path request. The contained exception was: "+str(e), RNS.LOG_ERROR)
@staticmethod
def path_request(destination_hash, is_from_local_client, attached_interface):
def path_request(destination_hash, is_from_local_client, attached_interface, requestor_transport_id=None):
if attached_interface != None:
interface_str = " on "+str(attached_interface)
else:
@ -1590,49 +1601,59 @@ class Transport:
elif (RNS.Reticulum.transport_enabled() or is_from_local_client) and (destination_hash in Transport.destination_table):
RNS.log("Answering path request for "+RNS.prettyhexrep(destination_hash)+interface_str+", path is known", RNS.LOG_DEBUG)
packet = Transport.destination_table[destination_hash][6]
next_hop = Transport.destination_table[destination_hash][1]
received_from = Transport.destination_table[destination_hash][5]
now = time.time()
retries = Transport.PATHFINDER_R
local_rebroadcasts = 0
block_rebroadcasts = True
announce_hops = packet.hops
if is_from_local_client:
retransmit_timeout = now
if requestor_transport_id != None and next_hop == requestor_transport_id:
# TODO: Find a bandwidth efficient way to invalidate our
# known path on this signal. The obvious way of signing
# 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.
RNS.log("Not answering path request for "+RNS.prettyhexrep(destination_hash)+interface_str+", since next hop is the requestor", RNS.LOG_DEBUG)
else:
# TODO: Look at this timing
retransmit_timeout = now + Transport.PATH_REQUEST_GRACE # + (RNS.rand() * Transport.PATHFINDER_RW)
RNS.log("Answering path request for "+RNS.prettyhexrep(destination_hash)+interface_str+", path is known", RNS.LOG_DEBUG)
# This handles an edge case where a peer sends a past
# request for a destination just after an announce for
# said destination has arrived, but before it has been
# rebroadcast locally. In such a case the actual announce
# is temporarily held, and then reinserted when the path
# request has been served to the peer.
if packet.destination_hash in Transport.announce_table:
held_entry = Transport.announce_table[packet.destination_hash]
Transport.held_announces[packet.destination_hash] = held_entry
Transport.announce_table[packet.destination_hash] = [now, retransmit_timeout, retries, received_from, announce_hops, packet, local_rebroadcasts, block_rebroadcasts, attached_interface]
now = time.time()
retries = Transport.PATHFINDER_R
local_rebroadcasts = 0
block_rebroadcasts = True
announce_hops = packet.hops
if is_from_local_client:
retransmit_timeout = now
else:
# TODO: Look at this timing
retransmit_timeout = now + Transport.PATH_REQUEST_GRACE # + (RNS.rand() * Transport.PATHFINDER_RW)
# This handles an edge case where a peer sends a past
# request for a destination just after an announce for
# said destination has arrived, but before it has been
# rebroadcast locally. In such a case the actual announce
# is temporarily held, and then reinserted when the path
# request has been served to the peer.
if packet.destination_hash in Transport.announce_table:
held_entry = Transport.announce_table[packet.destination_hash]
Transport.held_announces[packet.destination_hash] = held_entry
Transport.announce_table[packet.destination_hash] = [now, retransmit_timeout, retries, received_from, announce_hops, packet, local_rebroadcasts, block_rebroadcasts, attached_interface]
elif is_from_local_client:
# Forward path request on all interfaces
# except the local client
RNS.log("Forwarding path request for "+RNS.prettyhexrep(destination_hash)+interface_str+" from local client to other local clients", RNS.LOG_DEBUG)
RNS.log("Forwarding path request from local client for "+RNS.prettyhexrep(destination_hash)+interface_str+" to all other interfaces", RNS.LOG_DEBUG)
for interface in Transport.interfaces:
if not interface == attached_interface:
Transport.request_path_on_interface(destination_hash, 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
RNS.log("Forwarding path request for "+RNS.prettyhexrep(destination_hash)+interface_str+" to local clients", RNS.LOG_DEBUG)
for interface in Transport.local_client_interfaces:
Transport.request_path_on_interface(destination_hash, interface)
Transport.request_path(destination_hash, interface)
else:
RNS.log("Ignoring path request for "+RNS.prettyhexrep(destination_hash)+interface_str+", no path known", RNS.LOG_DEBUG)

View File

@ -119,7 +119,7 @@ def program_setup(configdir, dispall=False, verbosity = 0):
print(" Traffic : {txb}\n {rxb}".format(rxb=size_str(ifstat["rxb"]), txb=size_str(ifstat["txb"])))
if "transport_id" in stats and stats["transport_id"] != None:
print("\n Transport Instance "+RNS.prettyhexrep(stats["transport_id"])+" running")
print("\n Reticulum Transport Instance "+RNS.prettyhexrep(stats["transport_id"])+" running")
print("")