mirror of
https://github.com/markqvist/Reticulum.git
synced 2024-08-22 07:00:29 +00:00
540 lines
22 KiB
Python
Executable File
540 lines
22 KiB
Python
Executable File
# MIT License
|
|
#
|
|
# Copyright (c) 2016-2023 Mark Qvist / unsigned.io and contributors.
|
|
#
|
|
# Permission is hereby granted, free of charge, to any person obtaining a copy
|
|
# of this software and associated documentation files (the "Software"), to deal
|
|
# in the Software without restriction, including without limitation the rights
|
|
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
|
# copies of the Software, and to permit persons to whom the Software is
|
|
# furnished to do so, subject to the following conditions:
|
|
#
|
|
# The above copyright notice and this permission notice shall be included in all
|
|
# copies or substantial portions of the Software.
|
|
#
|
|
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
|
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
|
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
|
|
# SOFTWARE.
|
|
|
|
import threading
|
|
import struct
|
|
import math
|
|
import time
|
|
import RNS
|
|
|
|
class Packet:
|
|
"""
|
|
The Packet class is used to create packet instances that can be sent
|
|
over a Reticulum network. Packets will automatically be encrypted if
|
|
they are addressed to a ``RNS.Destination.SINGLE`` destination,
|
|
``RNS.Destination.GROUP`` destination or a :ref:`RNS.Link<api-link>`.
|
|
|
|
For ``RNS.Destination.GROUP`` destinations, Reticulum will use the
|
|
pre-shared key configured for the destination. All packets to group
|
|
destinations are encrypted with the same AES-128 key.
|
|
|
|
For ``RNS.Destination.SINGLE`` destinations, Reticulum will use a newly
|
|
derived ephemeral AES-128 key for every packet.
|
|
|
|
For :ref:`RNS.Link<api-link>` destinations, Reticulum will use per-link
|
|
ephemeral keys, and offers **Forward Secrecy**.
|
|
|
|
:param destination: A :ref:`RNS.Destination<api-destination>` instance to which the packet will be sent.
|
|
:param data: The data payload to be included in the packet as *bytes*.
|
|
:param create_receipt: Specifies whether a :ref:`RNS.PacketReceipt<api-packetreceipt>` should be created when instantiating the packet.
|
|
"""
|
|
|
|
# Packet types
|
|
DATA = 0x00 # Data packets
|
|
ANNOUNCE = 0x01 # Announces
|
|
LINKREQUEST = 0x02 # Link requests
|
|
PROOF = 0x03 # Proofs
|
|
types = [DATA, ANNOUNCE, LINKREQUEST, PROOF]
|
|
|
|
# Header types
|
|
HEADER_1 = 0x00 # Normal header format
|
|
HEADER_2 = 0x01 # Header format used for packets in transport
|
|
header_types = [HEADER_1, HEADER_2]
|
|
|
|
# Packet context types
|
|
NONE = 0x00 # Generic data packet
|
|
RESOURCE = 0x01 # Packet is part of a resource
|
|
RESOURCE_ADV = 0x02 # Packet is a resource advertisement
|
|
RESOURCE_REQ = 0x03 # Packet is a resource part request
|
|
RESOURCE_HMU = 0x04 # Packet is a resource hashmap update
|
|
RESOURCE_PRF = 0x05 # Packet is a resource proof
|
|
RESOURCE_ICL = 0x06 # Packet is a resource initiator cancel message
|
|
RESOURCE_RCL = 0x07 # Packet is a resource receiver cancel message
|
|
CACHE_REQUEST = 0x08 # Packet is a cache request
|
|
REQUEST = 0x09 # Packet is a request
|
|
RESPONSE = 0x0A # Packet is a response to a request
|
|
PATH_RESPONSE = 0x0B # Packet is a response to a path request
|
|
COMMAND = 0x0C # Packet is a command
|
|
COMMAND_STATUS = 0x0D # Packet is a status of an executed command
|
|
CHANNEL = 0x0E # Packet contains link channel data
|
|
KEEPALIVE = 0xFA # Packet is a keepalive packet
|
|
LINKIDENTIFY = 0xFB # Packet is a link peer identification proof
|
|
LINKCLOSE = 0xFC # Packet is a link close message
|
|
LINKPROOF = 0xFD # Packet is a link packet proof
|
|
LRRTT = 0xFE # Packet is a link request round-trip time measurement
|
|
LRPROOF = 0xFF # Packet is a link request proof
|
|
|
|
# This is used to calculate allowable
|
|
# payload sizes
|
|
HEADER_MAXSIZE = RNS.Reticulum.HEADER_MAXSIZE
|
|
MDU = RNS.Reticulum.MDU
|
|
|
|
# With an MTU of 500, the maximum of data we can
|
|
# send in a single encrypted packet is given by
|
|
# the below calculation; 383 bytes.
|
|
ENCRYPTED_MDU = math.floor((RNS.Reticulum.MDU-RNS.Identity.FERNET_OVERHEAD-RNS.Identity.KEYSIZE//16)/RNS.Identity.AES128_BLOCKSIZE)*RNS.Identity.AES128_BLOCKSIZE - 1
|
|
"""
|
|
The maximum size of the payload data in a single encrypted packet
|
|
"""
|
|
PLAIN_MDU = MDU
|
|
"""
|
|
The maximum size of the payload data in a single unencrypted packet
|
|
"""
|
|
|
|
TIMEOUT_PER_HOP = RNS.Reticulum.DEFAULT_PER_HOP_TIMEOUT
|
|
|
|
def __init__(self, destination, data, packet_type = DATA, context = NONE, transport_type = RNS.Transport.BROADCAST, header_type = HEADER_1, transport_id = None, attached_interface = None, create_receipt = True):
|
|
if destination != None:
|
|
if transport_type == None:
|
|
transport_type = RNS.Transport.BROADCAST
|
|
|
|
self.header_type = header_type
|
|
self.packet_type = packet_type
|
|
self.transport_type = transport_type
|
|
self.context = context
|
|
|
|
self.hops = 0;
|
|
self.destination = destination
|
|
self.transport_id = transport_id
|
|
self.data = data
|
|
self.flags = self.get_packed_flags()
|
|
|
|
self.raw = None
|
|
self.packed = False
|
|
self.sent = False
|
|
self.create_receipt = create_receipt
|
|
self.receipt = None
|
|
self.fromPacked = False
|
|
else:
|
|
self.raw = data
|
|
self.packed = True
|
|
self.fromPacked = True
|
|
self.create_receipt = False
|
|
|
|
self.MTU = RNS.Reticulum.MTU
|
|
self.sent_at = None
|
|
self.packet_hash = None
|
|
|
|
self.attached_interface = attached_interface
|
|
self.receiving_interface = None
|
|
self.rssi = None
|
|
self.snr = None
|
|
self.q = None
|
|
|
|
def get_packed_flags(self):
|
|
if self.context == Packet.LRPROOF:
|
|
packed_flags = (self.header_type << 6) | (self.transport_type << 4) | (RNS.Destination.LINK << 2) | self.packet_type
|
|
else:
|
|
packed_flags = (self.header_type << 6) | (self.transport_type << 4) | (self.destination.type << 2) | self.packet_type
|
|
return packed_flags
|
|
|
|
def pack(self):
|
|
self.destination_hash = self.destination.hash
|
|
self.header = b""
|
|
self.header += struct.pack("!B", self.flags)
|
|
self.header += struct.pack("!B", self.hops)
|
|
|
|
if self.context == Packet.LRPROOF:
|
|
self.header += self.destination.link_id
|
|
self.ciphertext = self.data
|
|
else:
|
|
if self.header_type == Packet.HEADER_1:
|
|
self.header += self.destination.hash
|
|
|
|
if self.packet_type == Packet.ANNOUNCE:
|
|
# Announce packets are not encrypted
|
|
self.ciphertext = self.data
|
|
elif self.packet_type == Packet.LINKREQUEST:
|
|
# Link request packets are not encrypted
|
|
self.ciphertext = self.data
|
|
elif self.packet_type == Packet.PROOF and self.context == Packet.RESOURCE_PRF:
|
|
# Resource proofs are not encrypted
|
|
self.ciphertext = self.data
|
|
elif self.packet_type == Packet.PROOF and self.destination.type == RNS.Destination.LINK:
|
|
# Packet proofs over links are not encrypted
|
|
self.ciphertext = self.data
|
|
elif self.context == Packet.RESOURCE:
|
|
# A resource takes care of encryption
|
|
# by itself
|
|
self.ciphertext = self.data
|
|
elif self.context == Packet.KEEPALIVE:
|
|
# Keepalive packets contain no actual
|
|
# data
|
|
self.ciphertext = self.data
|
|
elif self.context == Packet.CACHE_REQUEST:
|
|
# Cache-requests are not encrypted
|
|
self.ciphertext = self.data
|
|
else:
|
|
# In all other cases, we encrypt the packet
|
|
# with the destination's encryption method
|
|
self.ciphertext = self.destination.encrypt(self.data)
|
|
|
|
if self.header_type == Packet.HEADER_2:
|
|
if self.transport_id != None:
|
|
self.header += self.transport_id
|
|
self.header += self.destination.hash
|
|
|
|
if self.packet_type == Packet.ANNOUNCE:
|
|
# Announce packets are not encrypted
|
|
self.ciphertext = self.data
|
|
else:
|
|
raise IOError("Packet with header type 2 must have a transport ID")
|
|
|
|
|
|
self.header += bytes([self.context])
|
|
self.raw = self.header + self.ciphertext
|
|
|
|
if len(self.raw) > self.MTU:
|
|
raise IOError("Packet size of "+str(len(self.raw))+" exceeds MTU of "+str(self.MTU)+" bytes")
|
|
|
|
self.packed = True
|
|
self.update_hash()
|
|
|
|
|
|
def unpack(self):
|
|
try:
|
|
self.flags = self.raw[0]
|
|
self.hops = self.raw[1]
|
|
|
|
self.header_type = (self.flags & 0b01000000) >> 6
|
|
self.transport_type = (self.flags & 0b00110000) >> 4
|
|
self.destination_type = (self.flags & 0b00001100) >> 2
|
|
self.packet_type = (self.flags & 0b00000011)
|
|
|
|
DST_LEN = RNS.Reticulum.TRUNCATED_HASHLENGTH//8
|
|
|
|
if self.header_type == Packet.HEADER_2:
|
|
self.transport_id = self.raw[2:DST_LEN+2]
|
|
self.destination_hash = self.raw[DST_LEN+2:2*DST_LEN+2]
|
|
self.context = ord(self.raw[2*DST_LEN+2:2*DST_LEN+3])
|
|
self.data = self.raw[2*DST_LEN+3:]
|
|
else:
|
|
self.transport_id = None
|
|
self.destination_hash = self.raw[2:DST_LEN+2]
|
|
self.context = ord(self.raw[DST_LEN+2:DST_LEN+3])
|
|
self.data = self.raw[DST_LEN+3:]
|
|
|
|
self.packed = False
|
|
self.update_hash()
|
|
return True
|
|
|
|
except Exception as e:
|
|
RNS.log("Received malformed packet, dropping it. The contained exception was: "+str(e), RNS.LOG_EXTREME)
|
|
return False
|
|
|
|
def send(self):
|
|
"""
|
|
Sends the packet.
|
|
|
|
:returns: A :ref:`RNS.PacketReceipt<api-packetreceipt>` instance if *create_receipt* was set to *True* when the packet was instantiated, if not returns *None*. If the packet could not be sent *False* is returned.
|
|
"""
|
|
if not self.sent:
|
|
if self.destination.type == RNS.Destination.LINK:
|
|
if self.destination.status == RNS.Link.CLOSED:
|
|
raise IOError("Attempt to transmit over a closed link")
|
|
else:
|
|
self.destination.last_outbound = time.time()
|
|
self.destination.tx += 1
|
|
self.destination.txbytes += len(self.data)
|
|
|
|
if not self.packed:
|
|
self.pack()
|
|
|
|
if RNS.Transport.outbound(self):
|
|
return self.receipt
|
|
else:
|
|
RNS.log("No interfaces could process the outbound packet", RNS.LOG_ERROR)
|
|
self.sent = False
|
|
self.receipt = None
|
|
return False
|
|
|
|
else:
|
|
raise IOError("Packet was already sent")
|
|
|
|
def resend(self):
|
|
"""
|
|
Re-sends the packet.
|
|
|
|
:returns: A :ref:`RNS.PacketReceipt<api-packetreceipt>` instance if *create_receipt* was set to *True* when the packet was instantiated, if not returns *None*. If the packet could not be sent *False* is returned.
|
|
"""
|
|
if self.sent:
|
|
# Re-pack the packet to obtain new ciphertext for
|
|
# encrypted destinations
|
|
self.pack()
|
|
|
|
if RNS.Transport.outbound(self):
|
|
return self.receipt
|
|
else:
|
|
RNS.log("No interfaces could process the outbound packet", RNS.LOG_ERROR)
|
|
self.sent = False
|
|
self.receipt = None
|
|
return False
|
|
else:
|
|
raise IOError("Packet was not sent yet")
|
|
|
|
def prove(self, destination=None):
|
|
if self.fromPacked and hasattr(self, "destination") and self.destination:
|
|
if self.destination.identity and self.destination.identity.prv:
|
|
self.destination.identity.prove(self, destination)
|
|
elif self.fromPacked and hasattr(self, "link") and self.link:
|
|
self.link.prove_packet(self)
|
|
else:
|
|
RNS.log("Could not prove packet associated with neither a destination nor a link", RNS.LOG_ERROR)
|
|
|
|
# Generates a special destination that allows Reticulum
|
|
# to direct the proof back to the proved packet's sender
|
|
def generate_proof_destination(self):
|
|
return ProofDestination(self)
|
|
|
|
def validate_proof_packet(self, proof_packet):
|
|
return self.receipt.validate_proof_packet(proof_packet)
|
|
|
|
def validate_proof(self, proof):
|
|
return self.receipt.validate_proof(proof)
|
|
|
|
def update_hash(self):
|
|
self.packet_hash = self.get_hash()
|
|
|
|
def get_hash(self):
|
|
return RNS.Identity.full_hash(self.get_hashable_part())
|
|
|
|
def getTruncatedHash(self):
|
|
return RNS.Identity.truncated_hash(self.get_hashable_part())
|
|
|
|
def get_hashable_part(self):
|
|
hashable_part = bytes([self.raw[0] & 0b00001111])
|
|
if self.header_type == Packet.HEADER_2:
|
|
hashable_part += self.raw[(RNS.Identity.TRUNCATED_HASHLENGTH//8)+2:]
|
|
else:
|
|
hashable_part += self.raw[2:]
|
|
|
|
return hashable_part
|
|
|
|
class ProofDestination:
|
|
def __init__(self, packet):
|
|
self.hash = packet.get_hash()[:RNS.Reticulum.TRUNCATED_HASHLENGTH//8];
|
|
self.type = RNS.Destination.SINGLE
|
|
|
|
def encrypt(self, plaintext):
|
|
return plaintext
|
|
|
|
|
|
class PacketReceipt:
|
|
"""
|
|
The PacketReceipt class is used to receive notifications about
|
|
:ref:`RNS.Packet<api-packet>` instances sent over the network. Instances
|
|
of this class are never created manually, but always returned from
|
|
the *send()* method of a :ref:`RNS.Packet<api-packet>` instance.
|
|
"""
|
|
# Receipt status constants
|
|
FAILED = 0x00
|
|
SENT = 0x01
|
|
DELIVERED = 0x02
|
|
CULLED = 0xFF
|
|
|
|
|
|
EXPL_LENGTH = RNS.Identity.HASHLENGTH//8+RNS.Identity.SIGLENGTH//8
|
|
IMPL_LENGTH = RNS.Identity.SIGLENGTH//8
|
|
|
|
# Creates a new packet receipt from a sent packet
|
|
def __init__(self, packet):
|
|
self.hash = packet.get_hash()
|
|
self.truncated_hash = packet.getTruncatedHash()
|
|
self.sent = True
|
|
self.sent_at = time.time()
|
|
self.proved = False
|
|
self.status = PacketReceipt.SENT
|
|
self.destination = packet.destination
|
|
self.callbacks = PacketReceiptCallbacks()
|
|
self.concluded_at = None
|
|
self.proof_packet = None
|
|
|
|
if packet.destination.type == RNS.Destination.LINK:
|
|
self.timeout = packet.destination.rtt * packet.destination.traffic_timeout_factor
|
|
else:
|
|
self.timeout = RNS.Reticulum.get_instance().get_first_hop_timeout(self.destination.hash)
|
|
self.timeout += Packet.TIMEOUT_PER_HOP * RNS.Transport.hops_to(self.destination.hash)
|
|
|
|
def get_status(self):
|
|
"""
|
|
:returns: The status of the associated :ref:`RNS.Packet<api-packet>` instance. Can be one of ``RNS.PacketReceipt.SENT``, ``RNS.PacketReceipt.DELIVERED``, ``RNS.PacketReceipt.FAILED`` or ``RNS.PacketReceipt.CULLED``.
|
|
"""
|
|
return self.status
|
|
|
|
# Validate a proof packet
|
|
def validate_proof_packet(self, proof_packet):
|
|
if hasattr(proof_packet, "link") and proof_packet.link:
|
|
return self.validate_link_proof(proof_packet.data, proof_packet.link, proof_packet)
|
|
else:
|
|
return self.validate_proof(proof_packet.data, proof_packet)
|
|
|
|
# Validate a raw proof for a link
|
|
def validate_link_proof(self, proof, link, proof_packet=None):
|
|
# TODO: Hardcoded as explicit proofs for now
|
|
if True or len(proof) == PacketReceipt.EXPL_LENGTH:
|
|
# This is an explicit proof
|
|
proof_hash = proof[:RNS.Identity.HASHLENGTH//8]
|
|
signature = proof[RNS.Identity.HASHLENGTH//8:RNS.Identity.HASHLENGTH//8+RNS.Identity.SIGLENGTH//8]
|
|
if proof_hash == self.hash:
|
|
proof_valid = link.validate(signature, self.hash)
|
|
if proof_valid:
|
|
self.status = PacketReceipt.DELIVERED
|
|
self.proved = True
|
|
self.concluded_at = time.time()
|
|
self.proof_packet = proof_packet
|
|
link.last_proof = self.concluded_at
|
|
|
|
if self.callbacks.delivery != None:
|
|
try:
|
|
self.callbacks.delivery(self)
|
|
except Exception as e:
|
|
RNS.log("An error occurred while evaluating external delivery callback for "+str(link), RNS.LOG_ERROR)
|
|
RNS.log("The contained exception was: "+str(e), RNS.LOG_ERROR)
|
|
|
|
return True
|
|
else:
|
|
return False
|
|
else:
|
|
return False
|
|
elif len(proof) == PacketReceipt.IMPL_LENGTH:
|
|
pass
|
|
# TODO: Why is this disabled?
|
|
# signature = proof[:RNS.Identity.SIGLENGTH//8]
|
|
# proof_valid = self.link.validate(signature, self.hash)
|
|
# if proof_valid:
|
|
# self.status = PacketReceipt.DELIVERED
|
|
# self.proved = True
|
|
# self.concluded_at = time.time()
|
|
# if self.callbacks.delivery != None:
|
|
# self.callbacks.delivery(self)
|
|
# RNS.log("valid")
|
|
# return True
|
|
# else:
|
|
# RNS.log("invalid")
|
|
# return False
|
|
else:
|
|
return False
|
|
|
|
# Validate a raw proof
|
|
def validate_proof(self, proof, proof_packet=None):
|
|
if len(proof) == PacketReceipt.EXPL_LENGTH:
|
|
# This is an explicit proof
|
|
proof_hash = proof[:RNS.Identity.HASHLENGTH//8]
|
|
signature = proof[RNS.Identity.HASHLENGTH//8:RNS.Identity.HASHLENGTH//8+RNS.Identity.SIGLENGTH//8]
|
|
if proof_hash == self.hash:
|
|
proof_valid = self.destination.identity.validate(signature, self.hash)
|
|
if proof_valid:
|
|
self.status = PacketReceipt.DELIVERED
|
|
self.proved = True
|
|
self.concluded_at = time.time()
|
|
self.proof_packet = proof_packet
|
|
|
|
if self.callbacks.delivery != None:
|
|
try:
|
|
self.callbacks.delivery(self)
|
|
except Exception as e:
|
|
RNS.log("Error while executing proof validated callback. The contained exception was: "+str(e), RNS.LOG_ERROR)
|
|
|
|
return True
|
|
else:
|
|
return False
|
|
else:
|
|
return False
|
|
elif len(proof) == PacketReceipt.IMPL_LENGTH:
|
|
# This is an implicit proof
|
|
if self.destination.identity == None:
|
|
return False
|
|
|
|
signature = proof[:RNS.Identity.SIGLENGTH//8]
|
|
proof_valid = self.destination.identity.validate(signature, self.hash)
|
|
if proof_valid:
|
|
self.status = PacketReceipt.DELIVERED
|
|
self.proved = True
|
|
self.concluded_at = time.time()
|
|
self.proof_packet = proof_packet
|
|
|
|
if self.callbacks.delivery != None:
|
|
try:
|
|
self.callbacks.delivery(self)
|
|
except Exception as e:
|
|
RNS.log("Error while executing proof validated callback. The contained exception was: "+str(e), RNS.LOG_ERROR)
|
|
|
|
return True
|
|
else:
|
|
return False
|
|
else:
|
|
return False
|
|
|
|
def get_rtt(self):
|
|
"""
|
|
:returns: The round-trip-time in seconds
|
|
"""
|
|
return self.concluded_at - self.sent_at
|
|
|
|
def is_timed_out(self):
|
|
return (self.sent_at+self.timeout < time.time())
|
|
|
|
def check_timeout(self):
|
|
if self.status == PacketReceipt.SENT and self.is_timed_out():
|
|
if self.timeout == -1:
|
|
self.status = PacketReceipt.CULLED
|
|
else:
|
|
self.status = PacketReceipt.FAILED
|
|
|
|
self.concluded_at = time.time()
|
|
|
|
if self.callbacks.timeout:
|
|
thread = threading.Thread(target=self.callbacks.timeout, args=(self,))
|
|
thread.daemon = True
|
|
thread.start()
|
|
|
|
|
|
def set_timeout(self, timeout):
|
|
"""
|
|
Sets a timeout in seconds
|
|
|
|
:param timeout: The timeout in seconds.
|
|
"""
|
|
self.timeout = float(timeout)
|
|
|
|
def set_delivery_callback(self, callback):
|
|
"""
|
|
Sets a function that gets called if a successfull delivery has been proven.
|
|
|
|
:param callback: A *callable* with the signature *callback(packet_receipt)*
|
|
"""
|
|
self.callbacks.delivery = callback
|
|
|
|
# Set a function that gets called if the
|
|
# delivery times out
|
|
def set_timeout_callback(self, callback):
|
|
"""
|
|
Sets a function that gets called if the delivery times out.
|
|
|
|
:param callback: A *callable* with the signature *callback(packet_receipt)*
|
|
"""
|
|
self.callbacks.timeout = callback
|
|
|
|
class PacketReceiptCallbacks:
|
|
def __init__(self):
|
|
self.delivery = None
|
|
self.timeout = None |