Echo example

FPE/Destination.py

@@ -15,12 +15,17 @@ class Destination:
 	PADDINGSIZE= FPE.Identity.PADDINGSIZE;
 
 	# Constants
-	SINGLE     = 0x00;
+	SINGLE     = 0x00
-	GROUP      = 0x01;
+	GROUP      = 0x01
-	PLAIN      = 0x02;
+	PLAIN      = 0x02
-	LINK       = 0x03;
+	LINK       = 0x03
 	types      = [SINGLE, GROUP, PLAIN, LINK]
 
+	PROVE_NONE = 0x21
+	PROVE_APP  = 0x22
+	PROVE_ALL  = 0x23
+	proof_strategies = [PROVE_NONE, PROVE_APP, PROVE_ALL]
+
 	IN         = 0x11;
 	OUT        = 0x12;
 	directions = [IN, OUT]
@@ -56,20 +61,24 @@ class Destination:
 		if not direction in Destination.directions: raise ValueError("Unknown destination direction")
 		self.type = type
 		self.direction = direction
+		self.proof_strategy = Destination.PROVE_NONE
 		self.mtu = 0
 
-		if identity == None:
+		if identity != None and type == Destination.SINGLE:
+			aspects = aspects+(identity.hexhash,)
+
+		if identity == None and direction == Destination.IN:
 			identity = Identity()
-			identity.createKeys()
+			aspects = aspects+(identity.hexhash,)
 
 		self.identity = identity
-		aspects = aspects+(identity.hexhash,)
 
 		self.name = Destination.getDestinationName(app_name, *aspects)		
 		self.hash = Destination.getDestinationHash(app_name, *aspects)
 		self.hexhash = self.hash.encode("hex_codec")
 
 		self.callback = None
+		self.proofcallback = None
 
 		FPE.Transport.registerDestination(self)
 
@@ -81,11 +90,19 @@ class Destination:
 	def setCallback(self, callback):
 		self.callback = callback
 
+	def setProofCallback(self, callback):
+		self.proofcallback = callback
 
-	def receive(self, data):
+	def setProofStrategy(self, proof_strategy):
-		plaintext = self.decrypt(data)
+		if not proof_strategy in Destination.proof_strategies:
+			raise TypeError("Unsupported proof strategy")
+		else:
+			self.proof_strategy = proof_strategy
+
+	def receive(self, packet):
+		plaintext = self.decrypt(packet.data)
 		if plaintext != None and self.callback != None:
-			self.callback(plaintext, self)
+			self.callback(plaintext, packet)
 
 
 	def createKeys(self):

FPE/FlexPE.py

@@ -1,7 +1,7 @@
 from Interfaces import *
 import ConfigParser
-import jsonpickle
 from vendor.configobj import ConfigObj
+import atexit
 import struct
 import array
 import os.path
@@ -13,16 +13,12 @@ class FlexPE:
 	MTU          = 500
 	router       = None
 	config       = None
-	destinations = []
+	
-	interfaces   = []
 	configdir    = os.path.expanduser("~")+"/.flexpe"
 	configpath   = ""
 	storagepath  = ""
 	cachepath    = ""
 	
-	# TODO: Move this to Transport
-	packetlist   = []
-
 	def __init__(self,configdir=None):
 		if configdir != None:
 			FlexPE.configdir = configdir
@@ -48,23 +44,14 @@ class FlexPE:
 		FPE.Identity.loadKnownDestinations()
 		FlexPE.router = self
 
-	@staticmethod
+		atexit.register(FPE.Identity.exitHandler)
-	def addDestination(destination):
-		destination.MTU = FlexPE.MTU
-		FlexPE.destinations.append(destination)
-
-	@staticmethod
-	def outbound(raw):
-		for interface in FlexPE.interfaces:
-			if interface.OUT:
-				FPE.log("Transmitting via: "+str(interface), FPE.LOG_DEBUG)
-				interface.processOutgoing(raw)
 
 	def applyConfig(self):
-		for option in self.config["logging"]:
+		if "logging" in self.config:
-			value = self.config["logging"][option]
+			for option in self.config["logging"]:
-			if option == "loglevel":
+				value = self.config["logging"][option]
-				FPE.loglevel = int(value)
+				if option == "loglevel":
+					FPE.loglevel = int(value)
 
 		for name in self.config["interfaces"]:
 			c = self.config["interfaces"][name]
@@ -82,7 +69,7 @@ class FlexPE:
 						interface.OUT = True
 
 					interface.name = name
-					FlexPE.interfaces.append(interface)
+					FPE.Transport.interfaces.append(interface)
 
 				if c["type"] == "SerialInterface":
 					interface = SerialInterface.SerialInterface(
@@ -98,7 +85,7 @@ class FlexPE:
 						interface.OUT = True
 
 					interface.name = name
-					FlexPE.interfaces.append(interface)
+					FPE.Transport.interfaces.append(interface)
 
 			except Exception as e:
 				FPE.log("The interface \""+name+"\" could not be created. Check your configuration file for errors!", FPE.LOG_ERROR)

FPE/Identity.py

@@ -37,13 +37,23 @@ class Identity:
 			self.createKeys()
 
 	@staticmethod
-	def remember(hash, public_key, app_data = None):
+	def remember(packet_hash, destination_hash, public_key, app_data = None):
-		FPE.log("Remembering "+FPE.hexrep(hash, False), FPE.LOG_VERBOSE)
+		FPE.log("Remembering "+FPE.prettyhexrep(destination_hash), FPE.LOG_VERBOSE)
-		Identity.known_destinations[hash] = [time.time(), public_key, app_data]
+		Identity.known_destinations[destination_hash] = [time.time(), packet_hash, public_key, app_data]
+
 
 	@staticmethod
-	def recall(identity):
+	def recall(destination_hash):
-		pass
+		FPE.log("Searching for "+FPE.prettyhexrep(destination_hash)+"...", FPE.LOG_DEBUG)
+		if destination_hash in Identity.known_destinations:
+			identity_data = Identity.known_destinations[destination_hash]
+			identity = Identity(public_only=True)
+			identity.loadPublicKey(identity_data[2])
+			FPE.log("Found "+FPE.prettyhexrep(destination_hash)+" in known destinations", FPE.LOG_DEBUG)
+			return identity
+		else:
+			FPE.log("Could not find "+FPE.prettyhexrep(destination_hash)+" in known destinations", FPE.LOG_DEBUG)
+			return None
 
 	@staticmethod
 	def saveKnownDestinations():
@@ -80,7 +90,7 @@ class Identity:
 	@staticmethod
 	def validateAnnounce(packet):
 		if packet.packet_type == FPE.Packet.ANNOUNCE:
-			FPE.log("Validating announce from "+FPE.hexrep(packet.destination_hash), FPE.LOG_VERBOSE)
+			FPE.log("Validating announce from "+FPE.prettyhexrep(packet.destination_hash), FPE.LOG_VERBOSE)
 			destination_hash = packet.destination_hash
 			public_key = packet.data[10:Identity.DERKEYSIZE/8+10]
 			random_hash = packet.data[Identity.DERKEYSIZE/8+10:Identity.DERKEYSIZE/8+20]
@@ -96,11 +106,19 @@ class Identity:
 
 			if announced_identity.validate(signature, signed_data):
 				FPE.log("Announce is valid", FPE.LOG_VERBOSE)
-				FPE.Identity.remember(destination_hash, public_key)
+				FPE.Identity.remember(FPE.Identity.fullHash(packet.raw), destination_hash, public_key)
+				FPE.log("Stored valid announce from "+FPE.prettyhexrep(destination_hash), FPE.LOG_INFO)
+				del announced_identity
+				return True
 			else:
 				FPE.log("Announce is invalid", FPE.LOG_VERBOSE)
+				del announced_identity
+				return False
+
+	@staticmethod
+	def exitHandler():
+		Identity.saveKnownDestinations()
 
-			del announced_identity
 
 	def createKeys(self):
 		self.prv = rsa.generate_private_key(
@@ -119,10 +137,9 @@ class Identity:
 			format=serialization.PublicFormat.SubjectPublicKeyInfo
 		)
 
-		self.hash = Identity.truncatedHash(self.pub_bytes)
+		self.updateHashes()
-		self.hexhash = self.hash.encode("hex_codec")
 
-		FPE.log("Identity keys created, private length is "+str(len(self.prv_bytes))+" public length is "+str(len(self.pub_bytes)), FPE.LOG_INFO)
+		FPE.log("Identity keys created for "+FPE.prettyhexrep(self.hash), FPE.LOG_INFO)
 
 	def getPrivateKey(self):
 		return self.prv_bytes
@@ -138,10 +155,16 @@ class Identity:
 			encoding=serialization.Encoding.DER,
 			format=serialization.PublicFormat.SubjectPublicKeyInfo
 		)
+		self.updateHashes()
 
 	def loadPublicKey(self, key):
 		self.pub_bytes = key
 		self.pub = load_der_public_key(self.pub_bytes, backend=default_backend())
+		self.updateHashes()
+
+	def updateHashes(self):
+		self.hash = Identity.truncatedHash(self.pub_bytes)
+		self.hexhash = self.hash.encode("hex_codec")
 
 	def saveIdentity(self):
 		pass
@@ -150,7 +173,7 @@ class Identity:
 		pass
 
 	def encrypt(self, plaintext):
-		if self.prv != None:
+		if self.pub != None:
 			chunksize = (Identity.KEYSIZE-Identity.PADDINGSIZE)/8
 			chunks = int(math.ceil(len(plaintext)/(float(chunksize))))
 			# TODO: Remove debug output print("Plaintext size is "+str(len(plaintext))+", with "+str(chunks)+" chunks")
@@ -175,7 +198,7 @@ class Identity:
 			# TODO: Remove debug output print("Plaintext encrypted, ciphertext length is "+str(len(ciphertext))+" bytes.")
 			return ciphertext
 		else:
-			raise KeyError("Encryption failed because identity does not hold a private key")
+			raise KeyError("Encryption failed because identity does not hold a public key")
 
 
 	def decrypt(self, ciphertext):
@@ -238,11 +261,12 @@ class Identity:
 		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)
+		proof = FPE.Packet(destination, proof_data, FPE.Packet.PROOF)
+		proof.send()
+
+
 	def getRandomHash(self):
 		return self.truncatedHash(os.urandom(10))
 
-
-def identityExithandler():
-	Identity.saveKnownDestinations()
-
-atexit.register(identityExithandler)

FPE/Interfaces/UdpInterface.py

@@ -3,6 +3,7 @@ import SocketServer
 import threading
 import socket
 import sys
+import FPE
 
 class UdpInterface(Interface):
     bind_ip = None
@@ -36,9 +37,13 @@ class UdpInterface(Interface):
 
 
     def processIncoming(self, data):
+        # TODO: remove
+        #FPE.log("IN: "+FPE.prettyhexrep(data))
         self.owner.inbound(data)
 
     def processOutgoing(self,data):
+        # TODO: remove
+        #FPE.log("OUT: "+FPE.prettyhexrep(" "+data))
         udp_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
         udp_socket.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
         udp_socket.sendto(data, (self.forward_ip, self.forward_port))
@@ -52,5 +57,7 @@ class UdpInterfaceHandler(SocketServer.BaseRequestHandler):
 
     def handle(self):
         if (UdpInterfaceHandler.interface != None):
-            data = self.request[0].strip()
+            # TODO: remove
+            #FPE.log("Datagram contents: "+FPE.prettyhexrep(self.request[0]))
+            data = self.request[0]
             UdpInterfaceHandler.interface.processIncoming(data)

FPE/Packet.py

@@ -1,4 +1,5 @@
 import struct
+import time
 import FPE
 
 class Packet:
@@ -29,14 +30,19 @@ class Packet:
 			self.transport_id   = transport_id
 			self.data 		    = data
 			self.flags	 	    = self.getPackedFlags()
+			self.MTU     		= self.destination.MTU
 
 			self.raw    		= None
 			self.packed 		= False
 			self.sent   		= False
-			self.MTU    		= self.destination.MTU
+			self.fromPacked		= False
 		else:
-			self.raw    = data
+			self.raw            = data
-			self.packed = True
+			self.packed         = True
+			self.fromPacked     = True
+
+		self.sent_at = None
+		self.packet_hash = None
 
 	def getPackedFlags(self):
 		packed_flags = (self.header_type << 6) | (self.transport_type << 4) | (self.destination.type << 2) | self.packet_type
@@ -90,6 +96,8 @@ class Packet:
 			self.pack()
 			FPE.log("Size: "+str(len(self.raw))+" header is "+str(len(self.header))+" payload is "+str(len(self.ciphertext)), FPE.LOG_DEBUG)
 			FPE.Transport.outbound(self.raw)
+			self.packet_hash = FPE.Identity.fullHash(self.raw)
+			self.sent_at = time.time()
 			self.sent = True
 		else:
 			raise IOError("Packet was already sent")
@@ -98,4 +106,23 @@ class Packet:
 		if self.sent:
 			Transport.outbound(self.raw)
 		else:
-			raise IOError("Packet was not sent yet")
+			raise IOError("Packet was not sent yet")
+
+	def prove(self, destination):
+		if self.fromPacked and self.destination:
+			if self.destination.identity and self.destination.identity.prv:
+				self.destination.identity.prove(self, destination)
+
+	def validateProofPacket(self, proof_packet):
+		return self.validateProof(proof_packet.data)
+
+	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
+
+
+

FPE/Transport.py

@@ -8,11 +8,17 @@ class Transport:
 	TUNNEL       = 0x03;
 	types        = [BROADCAST, TRANSPORT, RELAY, TUNNEL]
 
+	interfaces	 	= []
+	destinations    = []
 	packet_hashlist = []
 
 	@staticmethod
 	def outbound(raw):
-		FPE.FlexPE.outbound(raw)
+		Transport.cacheRaw(raw)
+		for interface in Transport.interfaces:
+			if interface.OUT:
+				FPE.log("Transmitting via: "+str(interface), FPE.LOG_DEBUG)
+				interface.processOutgoing(raw)
 
 	@staticmethod
 	def inbound(raw):
@@ -22,15 +28,43 @@ class Transport:
 			Transport.packet_hashlist.append(packet_hash)
 			packet = FPE.Packet(None, raw)
 			packet.unpack()
+			packet.packet_hash = packet_hash
 
 			if packet.packet_type == FPE.Packet.ANNOUNCE:
-				FPE.Identity.validateAnnounce(packet)
+				if FPE.Identity.validateAnnounce(packet):
+					Transport.cache(packet)
 			
 			if packet.packet_type == FPE.Packet.RESOURCE:
-				for destination in FlexPE.destinations:
+				for destination in Transport.destinations:
 					if destination.hash == packet.destination_hash and destination.type == packet.destination_type:
-						destination.receive(packet.data)
+						packet.destination = destination
+						destination.receive(packet)
+						Transport.cache(packet)
+
+			if packet.packet_type == FPE.Packet.PROOF:
+				for destination in Transport.destinations:
+					if destination.hash == packet.destination_hash:
+						if destination.proofcallback != None:
+							destination.proofcallback(packet)
+						# TODO: add universal proof handling
 
 	@staticmethod
 	def registerDestination(destination):
-		FPE.FlexPE.addDestination(destination)
+		destination.MTU = FPE.FlexPE.MTU
+		if destination.direction == FPE.Destination.IN:
+			Transport.destinations.append(destination)
+
+	@staticmethod
+	def cache(packet):
+		FPE.Transport.cacheRaw(packet.raw)
+
+	@staticmethod
+	def cacheRaw(raw):
+		try:
+			file = open(FPE.FlexPE.cachepath+"/"+FPE.hexrep(FPE.Identity.fullHash(raw), delimit=False), "w")
+			file.write(raw)
+			file.close()
+			FPE.log("Wrote packet "+FPE.prettyhexrep(FPE.Identity.fullHash(raw))+" to cache", FPE.LOG_DEBUG)
+		except Exception as e:
+			FPE.log("Error writing packet to cache", FPE.LOG_ERROR)
+			FPE.log("The contained exception was: "+str(e))

FPE/Utilities/Echo.py

@@ -0,0 +1,222 @@
+import argparse
+import time
+import FPE
+
+# Let's define an app name. We'll use this for all
+# destinations we create. Since this echo example
+# is part of a range of example utilities, we'll put
+# them all within the app namespace "example_utilities"
+APP_NAME = "example_utilitites"
+
+# This initialisation is executed when the users chooses
+# to run as a server
+def server(configpath):
+	# We must first initialise FlexPE
+	fpe = FPE.FlexPE(configpath)
+	
+	# Randomly create a new identity for our echo server
+	server_identity = FPE.Identity()
+
+	# We create a destination that clients can query. We want
+	# to be able to verify echo replies to our clients, so we
+	# create a "single" destination that can receive encrypted
+	# messages. This way the client can send a request and be
+	# certain that no-one else than this destination was able
+	# to read it. 
+	echo_destination = FPE.Destination(server_identity, FPE.Destination.IN, FPE.Destination.SINGLE, APP_NAME, "echo", "request")
+	
+	# Tell the destination which function in our program to
+	# run when a packet is received.
+	echo_destination.setCallback(serverCallback)
+
+	# Everything's ready!
+	# Let's Wait for client requests or user input
+	announceLoop(echo_destination)
+
+
+def announceLoop(destination):
+	# Let the user know that everything is ready
+	FPE.log("Echo server running, hit enter to send announce (Ctrl-C to quit)")
+
+	# We enter a loop that runs until the users exits.
+	# If the user just hits enter, we will announce our server
+	# destination on the network, which will let clients know
+	# how to create messages directed towards it.
+	while True:
+		entered = raw_input()
+		destination.announce()
+		FPE.log("Sent announce from "+FPE.prettyhexrep(destination.hash))
+
+
+def serverCallback(message, packet):
+	# We have received am echo request from a client! When
+	# a client sends a request, it will include the hash of
+	# it's identity in the message. Since we know that the
+	# client has created a listening destination using this
+	# identity hash, we can construct an outgoing destination
+	# to direct our response to. The hash is sent in binary
+	# format, so we encode it as printable hexadecimal first,
+	# since aspect names need to in printable text.
+	client_identity_hexhash = message.encode("hex_codec")
+
+	# We can now create a destination that will let us reach
+	# the client which send the echo request. 
+	reply_destination = FPE.Destination(None, FPE.Destination.OUT, FPE.Destination.PLAIN, APP_NAME, "echo", "reply", client_identity_hexhash)
+
+	# Let's encode the reply destination hash in a readable
+	# way, so we can output some info to the user.
+	reply_destination_hexhash = reply_destination.hash.encode("hex_codec")
+
+	# Tell the user that we received an echo request, and
+	# that we are going to send a reply to the requester.
+	FPE.log("Received packet from <"+reply_destination_hexhash+">, sending reply")
+
+	# To let the client know that we got the echo request,
+	# we will use the "proof" functions of FlexPE. In most
+	# applications, the proving of packets will occur fully
+	# automatically, but in some cases like this, it can be
+	# beneficial to use the functions manually, since it
+	# neatly provides functionality that can unequivocally
+	# prove the receipt of the request to the client.
+	#
+	# Using the proof functionality is very simple, we just
+	# need to call the "prove" method on the packet we wish
+	# to prove, and specify which destination it should be
+	# directed to.
+	packet.prove(reply_destination)
+
+
+# We need a global list to hold sent echo requests
+sent_requests = []
+# This initialisation is executed when the users chooses
+# to run as a client
+def client(destination_hexhash, configpath):
+	# We need a binary representation of the destination
+	# hash that was entered on the command line
+	try:
+		if len(destination_hexhash) != 20:
+			raise ValueError("Destination length is invalid, must be 20 hexadecimal characters (10 bytes)")
+		destination_hash = destination_hexhash.decode("hex")
+	except:
+		FPE.log("Invalid destination entered. Check your input!")
+		exit()
+
+	# We must first initialise FlexPE
+	fpe = FPE.FlexPE()
+
+	# Randomly create a new identity for our echo server
+	client_identity = FPE.Identity()
+
+	# Let's set up a destination for replies to our echo
+	# requests. This destination will be used by the server
+	# to direct replies to. We're going to use a "plain"
+	# destination, so the server can send replies back
+	# without knowing any public keys of the client. In this
+	# case, such a design is benificial, since any client
+	# can send echo requests directly to the server, without
+	# first having to announce it's destination, or include
+	# public keys in the echo request
+	#
+	# We will use the destination naming convention of:
+	# example_utilities.echo.reply.<IDENTITY_HASH>
+	# where the last part is a hex representation of the hash
+	# of our "client_identity". We need to include this to
+	# create a unique destination for the server to respond to.
+	# If we had used a "single" destination, something equivalent
+	# to this process would have happened automatically.
+	reply_destination = FPE.Destination(client_identity, FPE.Destination.IN, FPE.Destination.PLAIN, APP_NAME, "echo", "reply", client_identity.hexhash)
+
+	# Since we are only expecting packets of the "proof"
+	# type to reach our reply destination, we just set the
+	# proof callback (and in this case not the normal
+	# message callback)
+	reply_destination.setProofCallback(clientProofCallback)
+
+	# Tell the user that the client is ready!
+	FPE.log("Echo client "+FPE.prettyhexrep(reply_destination.hash)+" ready, hit enter to send echo request (Ctrl-C to quit)")
+
+	# We enter a loop that runs until the user exits.
+	# If the user hits enter, we will try to send an
+	# echo request to the destination specified on the
+	# command line.
+	while True:
+		raw_input()
+		# To address the server, we need to know it's public
+		# key, so we check if FlexPE knows this destination.
+		# This is done by calling the "recall" method of the
+		# Identity module. If the destination is known, it will
+		# return an Identity instance that can be used in
+		# outgoing destinations.
+		server_identity = FPE.Identity.recall(destination_hash)
+		if server_identity != None:
+			# We got the correct identity instance from the
+			# recall method, so let's create an outgoing
+			# destination. We use the naming convention:
+			# example_utilities.echo.request
+			# Since this is a "single" destination, the identity
+			# hash will be automatically added to the end of
+			# the name.
+			request_destination = FPE.Destination(server_identity, FPE.Destination.OUT, FPE.Destination.SINGLE, APP_NAME, "echo", "request")
+
+			# The destination is ready, so let's create a packet.
+			# We set the destination to the request_destination
+			# that was just created, and the only data we add
+			# is the identity hash of our client identity.
+			# Including that information will let the server
+			# create a destination to send replies to.
+			echo_request = FPE.Packet(request_destination, client_identity.hash)
+
+			# Send the packet!
+			echo_request.send()
+
+			# Add the request to our list of sent packets
+			sent_requests.append(echo_request)
+
+			# Tell the user that the echo request was sent
+			FPE.log("Sent echo request to "+FPE.prettyhexrep(request_destination.hash))
+		else:
+			# If we do not know this destination, tell the
+			# user to wait for an announce to arrive.
+			FPE.log("Destination is not yet known. Wait for an announce to arrive.")
+
+def clientProofCallback(proof_packet):
+	now = time.time()
+	for unproven_packet in sent_requests:
+		if unproven_packet.packet_hash == proof_packet.data[:32]:
+			if unproven_packet.validateProofPacket(proof_packet):
+				rtt = now - unproven_packet.sent_at
+				if (rtt >= 1):
+					rtt = round(rtt, 3)
+					rttstring = str(rtt)+" seconds"
+				else:
+					rtt = round(rtt*1000, 3)
+					rttstring = str(rtt)+" milliseconds"
+				FPE.log(
+					"Valid echo reply, proved by "+FPE.prettyhexrep(unproven_packet.destination.hash)+
+					", round-trip time was "+rttstring
+					)
+			else:
+				FPE.log("Proof invalid")
+
+
+
+if __name__ == "__main__":
+	try:
+		parser = argparse.ArgumentParser(description="Simple echo server and client utility")
+		parser.add_argument("-s", "--server", action="store_true", help="wait for incoming packets from clients")
+		parser.add_argument("--config", action="store", default=None, help="path to alternative FlexPE config directory", type=str)
+		parser.add_argument("destination", nargs="?", default=None, help="hexadecimal hash of the server destination", type=str)
+		args = parser.parse_args()
+
+		if args.server:
+			configarg=None
+			if args.config:
+				configarg = args.config
+			server(configarg)
+		else:
+			configarg=None
+			if args.config:
+				configarg = args.config
+			client(args.destination, configarg)
+	except KeyboardInterrupt:
+		exit()

FPE/__init__.py

@@ -67,4 +67,9 @@ def hexrep(data, delimit=True):
 	if not delimit:
 		delimiter = ""
 	hexrep = delimiter.join("{:02x}".format(ord(c)) for c in data)
+	return hexrep
+
+def prettyhexrep(data):
+	delimiter = ""
+	hexrep = "<"+delimiter.join("{:02x}".format(ord(c)) for c in data)+">"
 	return hexrep

t.py

@@ -17,6 +17,7 @@ fpe = FlexPE()
 identity = Identity()
 
 d1=Destination(identity, Destination.IN, Destination.SINGLE, "messenger", "user")
+#d1.setProofStrategy(Destination.PROVE_ALL)
 d1.setCallback(testCallback)
 
 msg=""
@@ -28,7 +29,7 @@ pl = len(d1.identity.pub_bytes)
 
 d1.announce()
 p1=Packet(d1, msg)
-#p1.send()
+p1.send()
 
 # p2=Packet(d2,"Test af msg")
 # p2.send()