diff --git a/udp.py b/udp.py
index 2d6e1071e383c84cf91b309c98f9315644a96269..dc4274e253946e020ac9086b74dfc00d2cb76335 100644
--- a/udp.py
+++ b/udp.py
@@ -12,8 +12,45 @@ 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'])
+ compute_checksum(udp['Source Port'],udp['Dest Port'],udp['Server Sent'][8:(len(udp['Server Sent'])+8)])
+ #print(f"calculated checksum: {int(compute_checksum(2,1,b'AB'),2)}")
+
print(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()
+ print("here")
+ print(decodePacket(message))
+
+
+
+
+async def send_packet(websocket, sourcePort, destPort, payload):
+ print(type(payload))
+ checkSum = compute_checksum(sourcePort, destPort, payload)
+ print(checkSum)
+ destPort = destPort.to_bytes(2, 'little')
+ sourcePort = sourcePort.to_bytes(2, 'little')
+ length = 8 + len(payload)
+ length = length.to_bytes(2, 'little')
+ checkSum = checkSum.to_bytes(2, 'little')
+ print(f"length : {length}")
+
+ packet = sourcePort + destPort + length + checkSum + payload
+
+ print(destPort + sourcePort)
+ packet = base64.b64encode(packet)
+ await websocket.send(packet)
+
def decodePacket(response):
decoded = {}
@@ -32,16 +69,16 @@ def decodePacket(response):
def printUDPPacket(dict):
for key, value in dict.items():
print(f"{key}: {value}")
+
-def compute_checksum(sourcePort, destPort, payload, length):
+def compute_checksum(sourcePort, destPort, payload):
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')
+ length = (len(payload)+8).to_bytes(2, 'little')
calc = sourcePort + destPort + length + bytes(2) + payload
@@ -57,147 +94,20 @@ def compute_checksum(sourcePort, destPort, payload, length):
tmp = (calc[i] << 8) + calc[i+1]
sum += tmp
- sum = (sum << 16) + (sum & 0xFF)
-
- return ~sum
+ sum = (sum >> 16) + (sum & 0xFFFF)
+ sum = ~sum & 0xFFFF
+ sum = int(format(sum,'b'),2)
+ 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"))
- 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:
- 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
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")
# while 1:
- asyncio.run(main())
+ asyncio.run(mainSend())
time.sleep(10)