Initial commit

README.MD

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+# Ethernet over TCP over UART
+
+Scripts to forward an Ethernet interface (in Linux) over TCP and / or UART.
+
+These are terribly dirty scripts and don't work in all situations. Right now, only standard Ethernet frames are supported. Will add support for larger frames later.
+
+Still, might be useful as a proof of concept or something.
+
+## License
+
+Released into the Public Domain without any restrictions.

eth_tcp.py

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+#!/usr/bin/env python
+
+import sys
+import socket
+import threading
+import socket
+import time
+import os
+
+class MacDevReceiver(threading.Thread):
+	def __init__(self, macdev, ipdev):
+		self.macdev = macdev
+		self.ipdev = ipdev
+		threading.Thread.__init__(self)
+
+	def run(self):
+		while True:
+			r=self.macdev.recv(2000)
+			sys.stdout.write("[TCP] TX %d bytes.\n"%len(r))
+			self.ipdev.sendall(r)
+
+class IpDevReceiver(threading.Thread):
+	def __init__(self, macdev, ipdev):
+		self.macdev = macdev
+		self.ipdev = ipdev
+		threading.Thread.__init__(self)
+
+	def run(self):
+		while True:
+			r = self.ipdev.recv(10000)
+			if (len(r) <= 1518):
+				sys.stdout.write("[MAC] TX %d bytes.\n"%len(r))
+				self.macdev.send(r)
+			else:
+				sys.stdout.write("[MAC] Dropping %d bytes long frame.\n"%len(r))
+
+
+mode = sys.argv[1]
+dev = sys.argv[2]
+port = int(sys.argv[3])
+
+print("Setting IF to promisc mode...")
+os.system("sudo ip link set promisc on dev {}".format(dev))
+
+ETH_P_ALL=3
+m=socket.socket(socket.AF_PACKET, socket.SOCK_RAW, socket.htons(ETH_P_ALL))
+m.bind((dev, 0))
+
+# TODO: IP Frames w/ MTU > 1500
+# i = socket.socket(socket.AF_INET, socket.SOCK_RAW, socket.IPPROTO_RAW)
+# i.setsockopt(socket.IPPROTO_IP, socket.IP_HDRINCL, True)
+# i.send(ip payload)
+
+s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+if (mode == "s"):
+	s.bind(('localhost', port))
+	s.listen(1)
+	print("Waiting for TCP connection on port {}...".format(port))
+	conn, addr = s.accept()
+else:
+	s.connect(("localhost", port))
+	conn = s
+
+print("Forwarding data...")
+
+macdev_r = MacDevReceiver(m, conn)
+macdev_r.start()
+macdev_s = IpDevReceiver(m, conn)
+macdev_s.start()
+
+while True:
+	time.sleep(1)

tcp_uart.py

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+#!/usr/bin/env python
+import socket
+import serial
+import threading
+import sys
+import time
+
+class IpDevReceiver(threading.Thread):
+	def __init__(self, serdev, ipdev):
+		self.serdev = serdev
+		self.ipdev = ipdev
+		threading.Thread.__init__(self)
+
+	def run(self):
+		while True:
+			r = self.ipdev.recv(10000)
+
+class IpDevReceiver(threading.Thread):
+	def __init__(self, ipdev, serdev):
+		self.serdev = serdev
+		self.ipdev = ipdev
+		threading.Thread.__init__(self)
+
+	def run(self):
+		while True:
+			r = self.ipdev.recv(10000)
+			l = len(r)
+			print("[TCP ] RX Frame")
+			ser.write(l.to_bytes(2, byteorder='little'))
+			ser.write(r)
+
+class SerDevReceiver(threading.Thread):
+	def __init__(self, ipdev, serdev):
+		self.serdev = serdev
+		self.ipdev = ipdev
+		self.buf = []
+		self.exp = 0
+		threading.Thread.__init__(self)
+
+	def run(self):
+		while True:
+			r = self.serdev.read(1)
+			if (len(r) <= 0):
+				print(".")
+				continue
+			self.buf += r
+			#print("RX {} bytes. Buffer at {}.".format(len(r), len(self.buf)))
+			while True:
+				if (self.exp > 0):
+					if (len(self.buf) >= self.exp):
+						print("[UART] Frame RX complete ({} bytes)".format(self.exp))
+						self.ipdev.sendall(bytes(self.buf[:self.exp]))
+						self.buf = self.buf[self.exp:]
+						self.exp = 0
+					else:
+						#print("Data frame incomplete")
+						break
+				elif len(self.buf) >= 2:
+					self.exp = self.buf[0] + (self.buf[1] << 8)
+					self.buf = self.buf[2:]
+					print("[UART] Frame start. Expecting {} bytes".format(self.exp))
+				else:
+					#print("Header still incomplete")
+					break
+
+
+mode = sys.argv[1]
+dev = sys.argv[2]
+port = int(sys.argv[3])
+
+s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+if (mode == "s"):
+	s.bind(('localhost', port))
+	s.listen(1)
+	print("Waiting for TCP connection on port {}...".format(port))
+	conn, addr = s.accept()
+else:
+	s.connect(("localhost", port))
+	conn = s
+
+print("Forwarding data...")
+
+ser = serial.Serial(dev, 1000000, timeout=1)
+
+serdev_r = SerDevReceiver(conn, ser)
+serdev_r.start()
+serdev_s = IpDevReceiver(conn, ser)
+serdev_s.start()
+
+while True:
+	time.sleep(1)