def start_receiving(self):
fileReceivers = []
buffer_message = []
self.sock = socket.socket(socket.AF_INET, # this specifies address family - IPv4 in this case
socket.SOCK_DGRAM) # UDP
print('myport: ', settings.my_port)
self.sock.bind(('', settings.my_port))
while True:
data, addr = self.sock.recvfrom(1480)
data = cryptograph.decode(cryptograph, data)
packet_identifier = data.get('identifier')
packet_flag = data.get('flag')
if (packet_flag == 'FIL' or packet_flag == 'FIE' or packet_flag == 'MSF'):
file_receiver_index = self.get_list_index(fileReceivers, packet_identifier)
if (file_receiver_index == -1):
fileReceivers.append(file_receiver.FileReceiver())
file_receiver_index = len(fileReceivers) - 1
fileReceivers[file_receiver_index].receive_file_packet(self.sock, addr, data)
if (packet_flag == 'FIE'):
fileReceivers.remove(fileReceivers[file_receiver_index])
elif (packet_flag == 'KIA'):
sender.build_and_send(self.sock, packet_identifier, 'KIA', 1, 0, '', addr)
elif (packet_flag == 'FGM'):
identifier = data.get('identifier')
fragmentNumber = data.get('fragmented')
buffer_message.append(data.get('data'))
self.confirmPacket(addr, identifier, fragmentNumber)
elif (packet_flag == 'FGE'):
identifier = data.get('identifier')
fragmentNumber = data.get('fragmented')
buffer_message.append(data.get('data'))
for fragment in buffer_message:
print(fragment, end="")
buffer_message.clear()
self.confirmPacket(addr, identifier, fragmentNumber)
else:
identifier = data.get('identifier')
fragmentNumber = data.get('fragmented')
self.confirmPacket(addr, identifier, fragmentNumber)
print('Received data: ', data.get('data'))
def sendFragmentedMsg(self, soc):
lastByte = 0
unsentMessageSize = len(self.MESSAGE)
identifier = cryptograph.generateIdentifier()
fragmentNumber = 0
while (unsentMessageSize > 0):
newLastByte = lastByte + settings.maxFragSize
paycheck = cryptograph.calculatePayCheck(self.MESSAGE[lastByte:newLastByte])
# completeMessage = sender.build_and_send(soc, identifier, 'FGM', fragmentNumber, paycheck, self.MESSAGE[lastByte:newLastByte])
new_flag = 'FGM'
if (unsentMessageSize - newLastByte - lastByte <= 0):
new_flag = 'FGE'
if (fragmentNumber % 2 == 0):
completeMessage = sender.build_and_send(soc, identifier, new_flag, fragmentNumber, paycheck, self.MESSAGE[lastByte:newLastByte])
self.waitForConfirmation(soc)
unsentMessageSize -= newLastByte - lastByte
lastByte = newLastByte
fragmentNumber += 1
def sendNOTFragmentedMsg(self, soc):
identifier = cryptograph.generateIdentifier()
paycheck = cryptograph.calculatePayCheck(self.MESSAGE)
completeMessage = sender.build_and_send(soc, identifier, 'MSG', 0, paycheck, self.MESSAGE)
self.waitForConfirmation(soc)
def waitForConfirmation(self, soc, identifier) -> bool:
self.soc.settimeout(settings.timeOutKeepAlive)
kia = 0
while True:
try:
data, addr = soc.recvfrom(1024)
data = cryptograph.decode(cryptograph, data)
packet_flag = data.get('flag')
if (packet_flag == 'KIA'):
kia = 0
continue
packetIdentifier = data.get('identifier')
if not (identifier == packetIdentifier):
print('ERROR: NOT MATCHING IDENTIFIERS (identifier: ',
identifier, ') !!! !!! !!!')
flag = data.get('flag')
if (flag == 'OKE'):
return False
elif (flag == 'MSF'):
self.missing_fragments = data.get('data').split('-')
return True
else:
print('ERROR: CONFIRMATION PACKET CONTAINS UNKNOWN FLAG: ',
flag, " !!! !!! !!!")
return True
except timeout:
print('Timeout')
sender.build_and_send(soc, identifier, 'KIA', 0, 0, '')
if (kia < 3):
kia += 1
print('KeepAlive send')
continue
else:
print('Connection was lost')
self.kill_thread = True
return False
continue
except ConnectionResetError:
print('Connection was lost')
self.kill_thread = True
return False
def send_initial_fragment(self, soc, identifier, file):
payCheck = cryptograph.calculatePayCheck(file.name)
completeMessage = sender.build_and_send(soc, identifier, 'FIL', 0,
payCheck, file.name)
while (self.waitForConfirmation(soc, identifier)):
continue
if (self.kill_thread == True):
return False
return True
def send_fragments(self, soc, identifier, file):
lastByte = 0
max_payload = settings.maxFragSize - settings.MY_HEADER
message = ' '
messages_list = []
fragmentNumber = 1
sending = True
initial_fragment_send = False
while sending:
for i in range(0, 50):
if not (initial_fragment_send):
if not (self.send_initial_fragment(self.soc, identifier,
file)):
return
initial_fragment_send = True
continue
message = b'' + file.read(max_payload)
lastByte += message.__sizeof__() - 25
if (message == b''):
flag = 'FIE'
else:
flag = 'FIL'
payCheck = cryptograph.calculatePayCheck(message)
if (fragmentNumber == 10 and settings.sent_faulty):
payCheck = 0
completeMessage = sender.build_and_send(
soc, identifier, flag, fragmentNumber, payCheck, message)
messages_list.append(completeMessage)
if (flag == 'FIE'):
sending = False
print('File sent')
break
else:
fragmentNumber += 1
while (self.waitForConfirmation(soc, identifier)):
print('Re-sending fragment')
for miss_fragment in self.missing_fragments:
completeMessage = messages_list.__getitem__(
int(miss_fragment))
sender.send_message(soc, completeMessage)
if (self.kill_thread):
return
def requestFragments(self, addr, soc, identifier):
str_missing_fragments = self.get_string_of_missing_fragments()
sender.build_and_send(soc, identifier, 'MSF', 0, 0,
str_missing_fragments, addr)
def confirmPacket(self, addr, soc, identifier, fragmentNumber):
sender.build_and_send(soc, identifier, 'OKE', fragmentNumber, 0, '',
addr)
def requestFragment(self, addr, identifier, fragmentNumber):
sender.build_and_send(self.sock, identifier, 'MSF', fragmentNumber, 0, '', addr)