From 8aa2f8613af6bb27a57728eddfe677fa7c70186a Mon Sep 17 00:00:00 2001
From: Mark Qvist <mark@adepta.io>
Date: Wed, 25 Apr 2018 22:46:05 +0200
Subject: [PATCH] File transfer example

---
 Examples/Filetransfer.py |  4 +++-
 RNS/Packet.py            |  2 +-
 RNS/Reticulum.py         | 12 +++++++++---
 3 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/Examples/Filetransfer.py b/Examples/Filetransfer.py
index 9fb876b..d4a7f09 100644
--- a/Examples/Filetransfer.py
+++ b/Examples/Filetransfer.py
@@ -86,8 +86,10 @@ def client_connected(link):
 		# We pack a list of files for sending in a packet
 		data = umsgpack.packb(list_files())
 
+		RNS.log(str(len(data)))
+
 		# Check the size of the packed data
-		if len(data) <= RNS.Resource.SDU:
+		if len(data) <= RNS.Reticulum.LINK_MDU:
 			# If it fits in one packet, we will just
 			# send it as a single packet over the link.
 			list_packet = RNS.Packet(link, data)
diff --git a/RNS/Packet.py b/RNS/Packet.py
index 38321ea..c9f8e26 100755
--- a/RNS/Packet.py
+++ b/RNS/Packet.py
@@ -39,7 +39,7 @@ class Packet:
 
 	# This is used to calculate allowable
 	# payload sizes
-	HEADER_MAXSIZE = 23
+	HEADER_MAXSIZE = RNS.Reticulum.HEADER_MAXSIZE
 
 	# TODO: This should be calculated
 	# more intelligently
diff --git a/RNS/Reticulum.py b/RNS/Reticulum.py
index 3e1b6a7..0eea757 100755
--- a/RNS/Reticulum.py
+++ b/RNS/Reticulum.py
@@ -1,6 +1,7 @@
 from Interfaces import *
 import ConfigParser
 from vendor.configobj import ConfigObj
+import RNS
 import atexit
 import struct
 import array
@@ -11,9 +12,14 @@ import RNS
 #import traceback
 
 class Reticulum:
-	MTU          = 500
-	router       = None
-	config       = None
+	MTU            = 500
+	HEADER_MAXSIZE = 23
+
+	PAD_AES_HMAC   = 64
+	MDU            = MTU - HEADER_MAXSIZE
+	LINK_MDU       = MDU - PAD_AES_HMAC
+	router         = None
+	config         = None
 	
 	configdir    = os.path.expanduser("~")+"/.reticulum"
 	configpath   = ""