Proof handling

This commit is contained in:
Mark Qvist 2018-04-17 17:46:48 +02:00
parent dedea6ba11
commit 19d9b1a4a5
9 changed files with 283 additions and 58 deletions

3
.gitignore vendored
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@ -1,5 +1,4 @@
.DS_Store
*.pyc
t.py
t2.py
testutils
TODO

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@ -13,7 +13,7 @@ class Callbacks:
def __init__(self):
self.link_established = None
self.packet = None
self.proof = None
self.proof_requested = None
class Destination:
KEYSIZE = RNS.Identity.KEYSIZE;
@ -101,8 +101,8 @@ class Destination:
def packet_callback(self, callback):
self.callbacks.packet = callback
def proof_callback(self, callback):
self.callbacks.proof = callback
def proof_requested_callback(self, callback):
self.callbacks.proof_requested = callback
def setProofStrategy(self, proof_strategy):
if not proof_strategy in Destination.proof_strategies:

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@ -14,12 +14,14 @@ from cryptography.hazmat.primitives.asymmetric import rsa
from cryptography.hazmat.primitives.asymmetric import padding
class Identity:
#KEYSIZE = 1536
KEYSIZE = 1024
DERKEYSIZE = KEYSIZE+272
#KEYSIZE = 1536
KEYSIZE = 1024
DERKEYSIZE = KEYSIZE+272
# Padding size, not configurable
PADDINGSIZE= 336
# Non-configurable constants
PADDINGSIZE = 336 # In bits
HASHLENGTH = 256 # In bits
SIGLENGTH = KEYSIZE
# Storage
known_destinations = {}
@ -257,13 +259,21 @@ class Identity:
hashes.SHA256()
)
return True
except:
except Exception as e:
return False
else:
raise KeyError("Signature validation failed because identity does not hold a public key")
def prove(self, packet, destination):
proof_data = packet.packet_hash + self.sign(packet.packet_hash)
def prove(self, packet, destination=None):
signature = self.sign(packet.packet_hash)
if RNS.Reticulum.should_use_implicit_proof():
proof_data = signature
else:
proof_data = packet.packet_hash + signature
if destination == None:
destination = packet.generateProofDestination()
proof = RNS.Packet(destination, proof_data, RNS.Packet.PROOF)
proof.send()

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@ -28,7 +28,6 @@ class AX25():
CRC_CORRECT = chr(0xF0)+chr(0xB8)
# TODO: THIS CLASS IS NOT YET IMPLEMENTED --- PLACEHOLDER ONLY ---
class AX25KISSInterface(Interface):
MAX_CHUNK = 32768

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@ -2,6 +2,96 @@ import struct
import time
import RNS
class PacketReceipt:
# Receipt status constants
FAILED = 0x00
SENT = 0x01
DELIVERED = 0x02
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.getHash()
self.sent = True
self.sent_at = time.time()
self.timeout = Packet.TIMEOUT
self.proved = False
self.status = PacketReceipt.SENT
self.destination = packet.destination
self.callbacks = PacketReceiptCallbacks()
self.concluded_at = None
# Validate a proof packet
def validateProofPacket(self, proof_packet):
return self.validateProof(proof_packet.data)
# Validate a raw proof
def validateProof(self, proof):
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
if self.callbacks.delivery != None:
self.callbacks.delivery(self)
return True
else:
return False
else:
return False
elif len(proof) == PacketReceipt.IMPL_LENGTH:
# This is an implicit proof
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
if self.callbacks.delivery != None:
self.callbacks.delivery(self)
return True
else:
return False
else:
return False
def isTimedOut(self):
return (self.sent_at+self.timeout < time.time())
def checkTimeout(self):
if self.isTimedOut():
self.status = PacketReceipt.FAILED
self.concluded_at = time.time()
if self.callbacks.timeout:
self.callbacks.timeout(self)
# Set the timeout in seconds
def setTimeout(self, timeout):
self.timeout = float(timeout)
# Set a function that gets called when
# a successfull delivery has been proved
def delivery_callback(self, callback):
self.callbacks.delivery = callback
# Set a function that gets called if the
# delivery times out
def timeout_callback(self, callback):
self.callbacks.timeout = callback
class PacketReceiptCallbacks:
def __init__(self):
self.delivery = None
self.timeout = None
class Packet:
# Constants
DATA = 0x00;
@ -16,6 +106,9 @@ class Packet:
HEADER_4 = 0x03; # Reserved
header_types = [HEADER_1, HEADER_2, HEADER_3, HEADER_4]
# Defaults
TIMEOUT = 3600.0
def __init__(self, destination, data, packet_type = DATA, transport_type = RNS.Transport.BROADCAST, header_type = HEADER_1, transport_id = None):
if destination != None:
if transport_type == None:
@ -35,6 +128,7 @@ class Packet:
self.raw = None
self.packed = False
self.sent = False
self.receipt = None
self.fromPacked = False
else:
self.raw = data
@ -67,6 +161,7 @@ class Packet:
self.ciphertext = self.destination.encrypt(self.data)
else:
self.ciphertext = self.data
if self.header_type == Packet.HEADER_3:
self.header += self.destination.link_id
self.ciphertext = self.data
@ -103,10 +198,11 @@ class Packet:
if not self.packed:
self.pack()
RNS.Transport.outbound(self)
self.packet_hash = RNS.Identity.fullHash(self.raw)
self.sent_at = time.time()
self.sent = True
if RNS.Transport.outbound(self):
return self.receipt
else:
# TODO: Don't raise error here, handle gracefully
raise IOError("Packet could not be sent! Do you have any outbound interfaces configured?")
else:
raise IOError("Packet was already sent")
@ -116,21 +212,36 @@ class Packet:
else:
raise IOError("Packet was not sent yet")
def prove(self, destination):
def prove(self, destination=None):
if self.fromPacked and self.destination:
if self.destination.identity and self.destination.identity.prv:
self.destination.identity.prove(self, destination)
# Generates a special destination that allows Reticulum
# to direct the proof back to the proved packet's sender
def generateProofDestination(self):
return ProofDestination(self)
def validateProofPacket(self, proof_packet):
return self.validateProof(proof_packet.data)
return self.receipt.validateProofPacket(proof_packet)
def validateProof(self, proof):
proof_hash = proof[:32]
signature = proof[32:]
if proof_hash == self.packet_hash:
return self.destination.identity.validate(signature, proof_hash)
else:
return False
return self.receipt.validateProof(proof)
def updateHash(self):
self.packet_hash = self.getHash()
def getHash(self):
return RNS.Identity.fullHash(self.getHashablePart())
def getHashablePart(self):
return self.raw[0:1]+self.raw[2:]
class ProofDestination:
def __init__(self, packet):
self.hash = packet.getHash()[:10];
self.type = RNS.Destination.SINGLE
def encrypt(self, plaintext):
return plaintext

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@ -29,6 +29,7 @@ class Reticulum:
Reticulum.cachepath = Reticulum.configdir+"/storage/cache"
Reticulum.__allow_unencrypted = False
Reticulum.__use_implicit_proof = False
if not os.path.isdir(Reticulum.storagepath):
os.makedirs(Reticulum.storagepath)
@ -50,6 +51,8 @@ class Reticulum:
RNS.Identity.loadKnownDestinations()
Reticulum.router = self
RNS.Transport.scheduleJobs()
atexit.register(RNS.Identity.exitHandler)
def applyConfig(self):
@ -66,6 +69,11 @@ class Reticulum:
if "reticulum" in self.config:
for option in self.config["reticulum"]:
value = self.config["reticulum"][option]
if option == "use_implicit_proof":
if value == "true":
Reticulum.__use_implicit_proof = True
if value == "false":
Reticulum.__use_implicit_proof = False
if option == "allow_unencrypted":
if value == "true":
RNS.log("", RNS.LOG_CRITICAL)
@ -259,4 +267,8 @@ class Reticulum:
@staticmethod
def should_allow_unencrypted():
return Reticulum.__allow_unencrypted
return Reticulum.__allow_unencrypted
@staticmethod
def should_use_implicit_proof():
return Reticulum.__use_implicit_proof

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@ -1,4 +1,7 @@
import RNS
import time
import threading
from time import sleep
class Transport:
# Constants
@ -8,15 +11,65 @@ class Transport:
TUNNEL = 0x03;
types = [BROADCAST, TRANSPORT, RELAY, TUNNEL]
interfaces = []
destinations = []
pending_links = []
active_links = []
packet_hashlist = []
interfaces = [] # All active interfaces
destinations = [] # All active destinations
pending_links = [] # Links that are being established
active_links = [] # Links that are active
packet_hashlist = [] # A list of packet hashes for duplicate detection
receipts = [] # Receipts of all outgoing packets for proof processing
jobs_locked = False
jobs_running = False
job_interval = 0.250
receipts_last_checked = 0.0
receipts_check_interval = 1.0
hashlist_maxsize = 1000000
@staticmethod
def scheduleJobs():
thread = threading.Thread(target=Transport.jobloop)
thread.setDaemon(True)
thread.start()
@staticmethod
def jobloop():
while (True):
Transport.jobs()
sleep(Transport.job_interval)
@staticmethod
def jobs():
Transport.jobs_running = True
try:
if not Transport.jobs_locked:
# Process receipts list for timed-out packets
if Transport.receipts_last_checked+Transport.receipts_check_interval < time.time():
for receipt in Transport.receipts:
receipt.checkTimeout()
if receipt.status != RNS.PacketReceipt.SENT:
Transport.receipts.remove(receipt)
Transport.receipts_last_checked = time.time()
# Cull the packet hashlist if it has reached max size
while (len(Transport.packet_hashlist) > Transport.hashlist_maxsize):
Transport.packet_hashlist.pop(0)
except Exception as e:
RNS.log("An exception occurred while running Transport jobs.", RNS.LOG_ERROR)
RNS.log("The contained exception was: "+str(e), RNS.LOG_ERROR)
Transport.jobs_running = False
@staticmethod
def outbound(packet):
Transport.cacheRaw(packet.raw)
while (Transport.jobs_running):
sleep(0.1)
Transport.jobs_locked = True
packet.updateHash()
sent = False
for interface in Transport.interfaces:
if interface.OUT:
should_transmit = True
@ -27,19 +80,38 @@ class Transport:
if should_transmit:
RNS.log("Transmitting "+str(len(packet.raw))+" bytes via: "+str(interface), RNS.LOG_DEBUG)
interface.processOutgoing(packet.raw)
sent = True
if sent:
packet.sent = True
packet.sent_at = time.time()
if (packet.packet_type == RNS.Packet.DATA):
packet.receipt = RNS.PacketReceipt(packet)
Transport.receipts.append(packet.receipt)
Transport.cache(packet)
Transport.jobs_locked = False
return sent
@staticmethod
def inbound(raw, interface=None):
packet_hash = RNS.Identity.fullHash(raw)
RNS.log(str(interface)+" received packet with hash "+RNS.prettyhexrep(packet_hash), RNS.LOG_DEBUG)
while (Transport.jobs_running):
sleep(0.1)
Transport.jobs_locked = True
packet = RNS.Packet(None, raw)
packet.unpack()
packet.updateHash()
packet.receiving_interface = interface
if not packet_hash in Transport.packet_hashlist:
Transport.packet_hashlist.append(packet_hash)
packet = RNS.Packet(None, raw)
packet.unpack()
packet.packet_hash = packet_hash
packet.receiving_interface = interface
RNS.log(str(interface)+" received packet with hash "+RNS.prettyhexrep(packet.packet_hash), RNS.LOG_DEBUG)
if not packet.packet_hash in Transport.packet_hashlist:
Transport.packet_hashlist.append(packet.packet_hash)
if packet.packet_type == RNS.Packet.ANNOUNCE:
if RNS.Identity.validateAnnounce(packet):
Transport.cache(packet)
@ -64,6 +136,13 @@ class Transport:
destination.receive(packet)
Transport.cache(packet)
if destination.proof_strategy == RNS.Destination.PROVE_ALL:
packet.prove()
if destination.proof_strategy == RNS.Destination.PROVE_APP:
if destination.callbacks.proof_requested:
destination.callbacks.proof_requested(packet)
if packet.packet_type == RNS.Packet.PROOF:
if packet.header_type == RNS.Packet.HEADER_3:
# This is a link request proof, forward
@ -72,11 +151,27 @@ class Transport:
if link.link_id == packet.destination_hash:
link.validateProof(packet)
else:
for destination in Transport.destinations:
if destination.hash == packet.destination_hash:
if destination.proofcallback != None:
destination.proofcallback(packet)
# TODO: add universal proof handling
# TODO: Make sure everything uses new proof handling
if len(packet.data) == RNS.PacketReceipt.EXPL_LENGTH:
proof_hash = packet.data[:RNS.Identity.HASHLENGTH/8]
else:
proof_hash = None
for receipt in Transport.receipts:
receipt_validated = False
if proof_hash != None:
# Only test validation if hash matches
if receipt.hash == proof_hash:
receipt_validated = receipt.validateProofPacket(packet)
else:
# In case of an implicit proof, we have
# to check every single outstanding receipt
receipt_validated = receipt.validateProofPacket(packet)
if receipt_validated:
Transport.receipts.remove(receipt)
Transport.jobs_locked = False
@staticmethod
def registerDestination(destination):
@ -112,15 +207,13 @@ class Transport:
@staticmethod
def cache(packet):
if RNS.Transport.shouldCache(packet):
RNS.Transport.cacheRaw(packet.raw)
try:
packet_hash = RNS.hexrep(packet.getHash(), delimit=False)
file = open(RNS.Reticulum.cachepath+"/"+packet_hash, "w")
file.write(packet.raw)
file.close()
RNS.log("Wrote packet "+packet_hash+" to cache", RNS.LOG_DEBUG)
except Exception as e:
RNS.log("Error writing packet to cache", RNS.LOG_ERROR)
RNS.log("The contained exception was: "+str(e))
@staticmethod
def cacheRaw(raw):
try:
file = open(RNS.Reticulum.cachepath+"/"+RNS.hexrep(RNS.Identity.fullHash(raw), delimit=False), "w")
file.write(raw)
file.close()
RNS.log("Wrote packet "+RNS.prettyhexrep(RNS.Identity.fullHash(raw))+" to cache", RNS.LOG_DEBUG)
except Exception as e:
RNS.log("Error writing packet to cache", RNS.LOG_ERROR)
RNS.log("The contained exception was: "+str(e))

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@ -9,6 +9,7 @@ from .Link import Link
from .Transport import Transport
from .Destination import Destination
from .Packet import Packet
from .Packet import PacketReceipt
modules = glob.glob(os.path.dirname(__file__)+"/*.py")
__all__ = [ os.path.basename(f)[:-3] for f in modules if not f.endswith('__init__.py')]

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@ -38,7 +38,7 @@ BOMS = {
BOM_UTF16: ('utf_16', 'utf_16'),
}
# All legal variants of the BOM codecs.
# TODO: the list of aliases is not meant to be exhaustive, is there a
# The list of aliases is not meant to be exhaustive, is there a
# better way ?
BOM_LIST = {
'utf_16': 'utf_16',