diff --git a/udp.py b/udp.py
index 2d6e1071e383c84cf91b309c98f9315644a96269..da6b01d0a46b7da1e0001448da135ecc932ddc1e 100644
--- a/udp.py
+++ b/udp.py
@@ -12,8 +12,44 @@ async def main():
message = await websocket.recv()
udp = decodePacket(message)
printUDPPacket(udp)
- compute_checksum(udp['Source Port'],udp['Dest Port'],udp['Server Sent'][8:(len(udp['Server Sent'])+8)],udp['Data Length'])
- print(bin(udp['Checksum']))
+ print(f"calculated checksum: {int(compute_checksum(udp['Source Port'],udp['Dest Port'],udp['Server Sent'][8:(len(udp['Server Sent'])+8)],udp['Data Length']),2)}")
+ #print(f"calculated checksum: {int(compute_checksum(2,1,b'AB',9),2)}")
+ print(f"looking for bin : {bin(udp['Checksum'])}")
+
+async def mainSend():
+ uri = "ws://localhost:5612"
+ async with websockets.connect(uri) as websocket:
+ await recv_and_decode_packet(websocket)
+ while True:
+ await send_packet(websocket, 0, 542, b'1111')
+ await recv_and_decode_packet(websocket)
+ time.sleep(1)
+
+async def recv_and_decode_packet(websocket):
+ message = await websocket.recv()
+ decodePacket(message)
+
+
+async def send_packet(websocket, destPort, sourcePort, payload):
+ print(type(payload))
+ checkSum = compute_checksum(sourcePort, destPort, payload, len(payload))
+ print(checkSum)
+ destPort.to_bytes(2, 'little')
+ sourcePort.to_bytes(2, 'little')
+ length = 8 + len(payload)
+ length.to_bytes(2, 'little')
+ print(f"length : {length}")
+ sourcePort = sourcePort << 48
+ destPort = destPort << 32
+ length = length << 16
+
+ packet = sourcePort + destPort + length + checkSum
+
+ print(destPort + sourcePort)
+ input()
+ await websocket.send()
+
+
def decodePacket(response):
decoded = {}
@@ -24,7 +60,7 @@ def decodePacket(response):
decoded['Dest Port'] = int.from_bytes(packet[2:4], 'little')
decoded['Data Length'] = int.from_bytes(packet[4:6], 'little')
decoded['Checksum'] = int.from_bytes(packet[6:8], 'little')
- decoded['Payload'] = packet[8:(len(packet)+8)].decode("utf-8")
+ decoded['Payload'] = packet[8:(len(packet))].decode("utf-8")
return decoded
@@ -34,170 +70,76 @@ def printUDPPacket(dict):
print(f"{key}: {value}")
def compute_checksum(sourcePort, destPort, payload, length):
- print(sourcePort)
- print(destPort)
- print(payload)
- print(length)
-
- sourcePort = sourcePort.to_bytes(2, 'little')
- destPort = destPort.to_bytes(2, 'little')
- length = length.to_bytes(2, 'little')
-
- calc = sourcePort + destPort + length + bytes(2) + payload
-
+ print(f"sourcePort: {sourcePort}")
+ print(f"destPort: {destPort}")
+ print(f"payload: {payload}")
+ print(f"length: {length}")
+ sourcePort = sourcePort.to_bytes(1, 'little')
+ destPort = destPort.to_bytes(1, 'little')
+ length = length.to_bytes(1, 'little')
+ print(f"sourcePort: {sourcePort}")
+ print(f"destPort: {destPort}")
+ print(f"payload: {payload}")
+ print(f"length: {length}")
+ print(len(length))
+
+ calc = bytes(1) + sourcePort + bytes(1) + destPort + bytes(1) + length + bytes(2) + payload
+ print(calc)
print(f"starting calc: {calc}")
- calcPayload = ""
- print(type(calcPayload))
sum = 0
if len(payload) % 2:
calc += bytes(1)
+ print(calc)
for i in range(0, len(calc), 2):
tmp = (calc[i] << 8) + calc[i+1]
sum += tmp
-
- sum = (sum << 16) + (sum & 0xFF)
-
- return ~sum
-
- # payload = bytearray(payload)
- print(type(payload))
- # if (len(payload) % 2) != 0:
- # print("0")
- # payload.append(bytes())
- x = 0
- i = 0
- print(len(payload))
- j = (len(payload) // 2)*2
- print(j)
- while i < j:
- x = format(payload[i],"b")
- for n in range(0,8 - len(x)): #n note used
- x = "0" + x
- y = format(payload[i+1],"b")
- for n in range(0,8 - len(y)):
- y = "0" + y
- z = x + y
- z = "0b" + z
- print(f"x: {x}")
- print(f"y: {y}")
- print(f"z: {z}")
- calc = calc + int(z,2)
- print(f"int of z: {int(z,2)}")
- print(f"calc after calc: {calc}")
- i += 2
- if len(payload) % 2 != 0:
- print(f"i: {i}")
- x = format(payload[i],"b")
- for f in range(0,8 - len(x)):
- x = "0" + x
-
- print(f"payload: {payload[i]}")
- y = "00000000"
- z = x + y
- print(x)
- print(z)
- z = "0b" + z
- calc = calc + int(z,2)
- # while i <= len(payload):
- # x = format(payload[i],"b")
- # for n in range(0,8 - len(x)): #n note used
- # x = "0" + x
- # y = format(payload[i+1],"b")
- # for n in range(0,8 - len(z)):
- # z = "0" + z
- # z = x + y
- # z = "0b" + z
- # calc = calc + int(z,2)
- # print(calc)
- # i += 2
- # else:
- # print("heres")
- # j = (len(payload) // 2)*2
- # print(j)
- # while i < j:
- # x = format(payload[i],"b")
- # for n in range(0,8 - len(x)): #n note used
- # print("hereres")
- # x = "0" + x
- # y = format(payload[i+1],"b")
- # print(f"y: {y}")
- # for n in range(0,8 - len(y)):
- # print("okkk")
- # y = "0" + y
- # z = x + y
- # print(f"length of z: {len(z)}")
- # z = "0b" + z
- # calc = calc + int(z,2)
- # print(calc)
- # i += 2
- # print(f"i: {i}")
- # x = format(payload[i],"b")
- # for f in range(0,8 - len(x)):
- # x = "0" + x
-
- # print(f"payload: {payload[i]}")
- # y = "00000000"
- # z = y + x
- # print(x)
- # print(z)
- # z = "0b" + z
- # calc = calc + int(z,2)
- # for byte in payload:
- # x = + 1
- # print(type(byte))
- # z = format(byte,"b")
- # calcPayload += z
- # calcPayload = "0b" + calcPayload
- # if x % 2 != 0:
- # calcPayload +="00000000"
- # print("here")
- print(f"before calc: {calc}")
- print(format(calc,"b"))
+ print(f"calc[i]: {calc[i]}")
+ print(format(calc[i], 'b'))
+ print(f"calc[i+1]: {calc[i+1]}")
+ print(f"temp: {tmp}")
+ print(f"temp b: {format(tmp, 'b')}")
+ print(i)
+ print(f"sum: {format(sum, 'b')}")
+
+ print(format(sum, 'b'))
+ # sum = (sum & 0xFFFF)
+
+ sum = format(sum, 'b')
+ sum = sum[-16+len(sum):]
+ print(sum)
+ print(len(sum))
+ for f in range(0,16 - len(sum)):
+ sum = "0" + sum
+ print("hello")
+ # sum = (sum << 16) + (sum & 0xFF)
+ print(sum)
flipped = ""
- calc = calc & 0xFFFF
- print(type(calc))
- calc = format(calc, "b")
- print(f"after calc1: {calc}")
- for f in range(0,16 - len(calc)):
- calc = "0" + calc
- print(f"after calc2: {calc}")
- print(int(calc,2))
- # print(format(calc,"b"))
- # calcPayload = bin(calc)
- for bit in calc:
+ # print(str(sum))
+ for bit in sum:
if bit == "1":
flipped += "0"
elif bit == "0":
flipped += "1"
# flipped += bit
print(flipped)
- print(int(flipped,2))
-
-
- #mod odd number then add 8 0's
-
-
+ return flipped
async def recv_message(websocket):
message = json.loads(await websocket.recv())
return message['payload']
-# 0000 0000 0111 0010
-# 1111 1101 1111 0111
-# 0000 0010 0000 1000
-# 0111 0110 0110 0101
-# 0111 0110 0110 0101
-# 1101 1111 0000 101
-# 1101 1111 0000 101
-# 0110 1111 1000 0101
-#1001 0000 0111 1010
-# 0111 0010 0000 0000
-#0011 1011 1100 1011
-# 1100 0100 0011 0100
if __name__ == "__main__":
print("Echo client")
-
+ print(f"calculated checksum: {int(compute_checksum(2,1,b'AB',9),2)}")
# while 1:
asyncio.run(main())
time.sleep(10)
+# 100 0110 1111 1000 0101
+# 1000110111110000101
+# 0110 1111 1000 0101
+# 1000110111110000101
+# 110 1111 1000 0101
+
+# 100 0110 1111 1000 0101
+# 1001 0000 0111 1010
\ No newline at end of file