def getSharedKey(clientPort):
msg = clientPort.recv(1024)
msgLen = int(msg[:utils.HEADER_LENGTH])
fullMsg = msg
while len(fullMsg) < msgLen:
msg = clientPort.recv(1024)
fullMsg += msg
msgFromClient = pickle.loads(fullMsg[utils.HEADER_LENGTH:])
serverPublicKey, secret = utils.generatePublicKey(
msgFromClient.publicKey.prime, msgFromClient.publicKey.root)
sharedKey = utils.generateFullKey(msgFromClient.publicKey, secret)
print(
f"msgLength: {msgLen}, opcode: {msgFromClient.header.opcode}, prime: {msgFromClient.publicKey.prime}, root: {msgFromClient.publicKey.root}, publicKey: {msgFromClient.publicKey.pub_key}, secret: {secret}, \nShared Key: {sharedKey}"
)
SetHeaderValues = utils.Header(utils.opcodeDict["PUBKEY"],
socket.gethostname(), None)
SetPublicKey = utils.PublicKey(msgFromClient.publicKey.prime,
msgFromClient.publicKey.root,
serverPublicKey.pub_key)
packet = utils.Packet(SetHeaderValues, SetPublicKey, None, None, None,
None)
msgToSend = pickle.dumps(packet)
msgToSend = bytes(f"{len(msgToSend):<{utils.HEADER_LENGTH}}",
"ascii") + msgToSend
clientPort.sendall(msgToSend)
print("Sent public key")
return sharedKey
def sendFileReq(filename):
SetHeaderValues=utils.Header(utils.opcodeDict["REQSERV"], socket.gethostname(), HOST)
packet = utils.Packet(SetHeaderValues, None, utils.ReqServ(filename), None, None, None)
msgToSend = pickle.dumps(packet)
extract_info(10)
msgToSend = bytes(f"{len(msgToSend):<{utils.HEADER_LENGTH}}", "ascii") + msgToSend
sock.sendall(msgToSend)
def getKeyPacket():
p = prime_generate()
generatedKey, secret = utils.generatePublicKey()
SetHeaderValues=utils.Header(utils.opcodeDict["PUBKEY"], socket.gethostname(), HOST)
SetPublcKeyValues=utils.PublicKey(generatedKey.prime, generatedKey.root, generatedKey.pub_key)
extract_info(10)
packet = utils.Packet(SetHeaderValues,SetPublcKeyValues , None, None, None, None)
msgToSend = pickle.dumps(packet)
msgToSend = bytes(f"{len(msgToSend):<{utils.HEADER_LENGTH}}", "ascii") + msgToSend
return msgToSend, secret
def main():
utils.initConfigs()
utils.clear()
print(
'Using configs from config.xml Receiver(this): {}\nSender: {} Simulator: {}'
.format(utils.RECEIVER_IP, utils.SIMULATOR_IP, utils.SENDER_IP))
print('Missing packet timeout seconds:', utils.timeout_sec)
print('Sender window size:', utils.window_size)
simulatorSocket = utils.createUdpSocket(utils.RECV_PORT)
simulatorHost = utils.SocketHost(simulatorSocket, utils.SIMULATOR_IP,
utils.RECV_PORT)
print('Receiver started, listening on port', utils.RECV_PORT,
'ctrl+c to exit')
try:
sendSocketHost = utils.SocketHost(simulatorSocket, utils.SIMULATOR_IP,
utils.SEND_PORT)
ack_window = []
while True:
# block here until client connects
data_packet = utils.readPacket(simulatorSocket)
print('Packet recv\'d: {} {} {}'.format(
utils.CMDS[data_packet.flag], data_packet.num,
data_packet.payload))
ack_packet = utils.Packet(utils.ACK, data_packet.num)
if len(ack_window
) < utils.window_size and ack_packet not in ack_window:
ack_window.append(ack_packet)
if len(ack_window) == utils.window_size:
print('window size {} filled, sending ACKs {}-{}'.format(
utils.window_size, ack_window[0].num,
ack_window[utils.window_size - 1].num))
for packet in ack_window:
utils.sendPacket(simulatorHost, packet)
ack_window = []
else:
print('Ignored dup packet, seq num {}. Curr window size {}'.
format(ack_packet.num, len(ack_window)))
except KeyboardInterrupt:
print('\nexit called.')
except Exception as e:
traceback.print_exc()
finally:
simulatorSocket.close()
def serveRequest(key, clientPort):
key = f"{key:<{utils.KEY_LENGTH}}"
msg = clientPort.recv(1024)
msgLen = int(msg[:utils.HEADER_LENGTH])
fullMsg = msg
while len(fullMsg) < msgLen:
msg = self.request.recv(1024)
fullMsg += msg
extract_info(10)
msgFromClient = pickle.loads(fullMsg[utils.HEADER_LENGTH:])
filename = msgFromClient.reqServ.filename
print(f"Requested file: {filename}")
try:
filepath = "files/" + filename
with open(filepath, 'rb') as file:
fileInfo = os.stat(filepath)
fileSize = fileInfo.st_size
# print(f"File size: {fileSize} bytes.")
extract_info(10)
# n=fileSize//1024
# r=fileSize%1024
# Info=FileINFO(n,r)
# infopacket = pickle.dumps(Info)
# clientPort.sendall(infopacket)
data = file.read(1024)
cipher = DES3.new(key)
while len(data) > 0:
blockLength = len(data)
if (blockLength < 1024):
rem = blockLength % 1024
if rem:
data += bytes(1024 - rem)
encrypted_text = cipher.encrypt(data)
dec_text = cipher.decrypt(encrypted_text)
SetHeadervalues = utils.Header(utils.opcodeDict["ENCMSG"],
socket.gethostname(), None)
packet = utils.Packet(
SetHeadervalues, None, None, None,
utils.EncodedMsg(encrypted_text, blockLength), None)
msgToSend = pickle.dumps(packet)
msgToSend = bytes(f"{len(msgToSend):<{utils.HEADER_LENGTH}}",
"ascii") + msgToSend
# print("s:,", len(msgToSend))
clientPort.sendall(msgToSend)
data = file.read(1024)
extract_info(10)
SetHeadervalues = utils.Header(utils.opcodeDict["REQCOM"],
socket.gethostname(), None)
packet = utils.Packet(SetHeadervalues, None, None, utils.ReqComp(400),
None, None)
msgToSend = pickle.dumps(packet)
msgToSend = bytes(f"{len(msgToSend):<{utils.HEADER_LENGTH}}",
"ascii") + msgToSend
clientPort.sendall(msgToSend)
print("file sent")
except FileNotFoundError:
print("File not found")
extract_info(10)
packet = utils.Packet(
utils.Header(utils.opcodeDict["DISCONNECT"], socket.gethostname(),
None), None, None, None, None, utils.Disconnect())
msgToSend = pickle.dumps(packet)
clientPort.sendall(msgToSend)
def main():
utils.initConfigs()
utils.clear()
print(
'Using configs from config.xml: Sender (this) {}\n Simulator: {} Receiver: {}'
.format(utils.SENDER_IP, utils.SIMULATOR_IP, utils.RECEIVER_IP))
print('ACK timeout seconds: ', utils.timeout_sec)
print('Window size: ', utils.window_size)
simulatorSocket = utils.createUdpSocket(utils.SEND_PORT)
simulatorHost = utils.SocketHost(simulatorSocket, utils.SIMULATOR_IP,
utils.SEND_PORT)
print('Sender started, connecting to simulator ', utils.SIMULATOR_IP,
' ctrl+c to exit')
try:
# make packets
window = []
seqNum = 1
while True:
for x in range(1, utils.window_size):
packet = utils.Packet(utils.DATA, seqNum, getRngString())
seqNum = seqNum + 1 if seqNum <= 998 else 1
window.append(packet)
packet = utils.Packet(utils.EOT, seqNum, getRngString())
seqNum += 1
window.append(packet)
retransmit = True
while retransmit:
retransmit = False
timed_out = False
for packet in window:
utils.sendPacket(simulatorHost, packet)
print('packet to simulator: {} {} {}'.format(
utils.CMDS[packet.flag], packet.num, packet.payload))
time.sleep(utils.send_delay_sec)
print('window sent included packets {}-{}'.format(
window[0].num, window[utils.window_size - 1].num))
for x in window:
ack_packet = utils.readPacket(simulatorSocket,
utils.timeout_sec)
if ack_packet.flag == utils.TIMEOUT:
timeout_msg = 'timeout while waiting for ACKs, resending packets {}-{}'.format(
window[0].num, window[utils.window_size - 1].num)
print(timeout_msg)
info_packet = utils.Packet(utils.TIMEOUT, 0,
timeout_msg)
utils.sendPacket(simulatorHost, info_packet)
timed_out = True
break
else:
print('ACK recv\'d: {} {} {}'.format(
utils.CMDS[ack_packet.flag], ack_packet.num,
ack_packet.payload))
if timed_out:
retransmit = True
# end retransmit
window = []
except KeyboardInterrupt:
print('\nexit called.')
except Exception as e:
traceback.print_exc()
finally:
simulatorSocket.close()