class FragStorage:
def __init__(self, fragId, totalSize, parentContainer):
self._fragId = fragId
self._totalSize = totalSize
self._parentContainer = parentContainer
self._received = 0
self._bufferStream = io.BytesIO()
self._offsetsReceived = set([])
self._cleanUpTimer = Timer(Minutes(5),
self._removeFromParentContainer)
self._cleanUpTimer.start()
def _removeFromParentContainer(self):
if self._fragId in self._parentContainer:
del self._parentContainer[self._fragId]
def insert(self, fragOffset, fragData):
if fragOffset in self._offsetsReceived: return
self._offsetsReceived.add(fragOffset)
self._bufferStream.seek(fragOffset)
self._bufferStream.write(fragData)
self._received += len(fragData)
self._cleanUpTimer.extend(Minutes(5))
def isComplete(self):
return self._received == self._totalSize
def getData(self):
return self._bufferStream.getvalue()
def cleanup(self):
self._cleanUpTimer.expire()
return self.getData()
def send_packet(self, packet):
# print(self, "send packet: ", packet)
self.transport.write(packet.__serialize__())
if packet.Type != PEEPPacket.SYN and packet.Type != PEEPPacket.DATA and packet.Type != PEEPPacket.RIP:
return
timer = Timer(Seconds(1), self.send_packet, packet)
self.timers.append(timer)
timer.start()
def resend(self, resntPacket):
if "DATA" in resntPacket.Type.upper(): #start timer again
#get timer
for seq, packet, timer, acked in self.sentBoxData:
if seq == resntPacket.SeqNo:
timer.cancel()
index = self.sentBoxData.index((seq, packet, timer, acked))
pacTimer = Timer(Seconds(self.timeoutValue), self.timeout,
packet)
pacTimer.start()
self.sentBoxData[index] = (
seq, packet, pacTimer, False
) #packet seq, packet, timer, acked or not
#start timer
elif "FIN" in resntPacket.Type.upper():
currentTimer = self.sentBoxData[-1][2]
currentTimer.cancel()
currentTimer = Timer(Seconds(self.timeoutValue), self.timeout,
self.sentBoxData[-1][1])
currentTimer.start()
self.sentBoxData[-1] = (self.sentBoxData[-1][0],
self.sentBoxData[-1][1], currentTimer,
False) #last packet since its FIN
elif "ACK" in resntPacket.Type.upper():
if "SYN" in resntPacket.Type.upper():
self.timHand.cancel()
self.timHand = Timer(Seconds(self.timeoutValue), self.timeout,
self.sentHand)
self.timHand.start()
elif "SYN" in resntPacket.Type.upper():
self.stateCon = 0
print("Im here")
self.timHand.cancel()
self.timHand = Timer(Seconds(self.timeoutValue), self.timeout,
self.sentHand)
self.timHand.start()
resendPacket = RIPPacket(Type=resntPacket.Type,
SeqNo=resntPacket.SeqNo,
AckNo=resntPacket.AckNo,
CRC=resntPacket.CRC,
Data=resntPacket.Data)
print("resend packet: Type = {}, SeqNo = {}, AckNo = {},\n CRC = {}".
format(resntPacket.Type, resntPacket.SeqNo, resntPacket.AckNo,
resntPacket.CRC.decode()))
self.transport.write(resendPacket.__serialize__())
class PEEP_Base(StackingProtocol):
INIT, HANDSHAKE, TRANS, TEARDOWN = [0, 1, 2, 3]
def __init__(self):
super().__init__()
self.state = PEEP_Base.INIT
self.window_size = 10
self.chunk_size = 1024
self.transport = None
self.deserializer = None
self.base_sequence_number = None
self.sequence_number = None
self.expected_sequence_number = None
self.send_window_start = None
self.send_window_end = None
self.receive_window_start = None
self.receive_window_end = None
self.data_size = 0
self.data = bytes()
self.timers = []
self.received_data = []
self.rip_timer = None
self.rip_sequence_number = None
self.piggyback = False
def data_received(self, data):
# print("data received")
self.deserializer.update(data)
for packet in self.deserializer.nextPackets():
if isinstance(packet, PEEPPacket) and packet.verifyChecksum():
self.handle_packets(packet)
def handle_packets(self, packet):
typenum = packet.Type
if typenum == PEEPPacket.SYN and self.state == PEEP_Base.INIT:
# print('received SYN')
self.handle_syn(packet)
elif typenum == PEEPPacket.SYNACK and self.state == PEEP_Base.HANDSHAKE:
print('-------------PEEP received SYNACK-------------')
self.handle_synack(packet)
elif typenum == PEEPPacket.ACK:
# print("received ACK")
self.handle_ack(packet)
elif typenum == PEEPPacket.DATA and (self.state == PEEP_Base.TRANS or
self.state == PEEP_Base.TEARDOWN):
# print('received Data')
self.handle_data(packet)
elif typenum == PEEPPacket.RIP and (self.state == PEEP_Base.TRANS or
self.state == PEEP_Base.TEARDOWN):
# print('received RIP')
self.handle_rip(packet)
elif typenum == PEEPPacket.RIPACK and self.state == PEEP_Base.TEARDOWN:
# print('received RIPACK')
self.handle_ripack(packet)
else:
print('received packet in bad state. type: ', typenum, " state ",
self.state)
def handle_syn(self, packet):
# print('checksum of SYN is correct')
packetback = PEEPPacket()
if packet.Data != FIELD_NOT_SET and packet.Data.decode(
) == "piggyback":
# print("syn: enable piggybacking")
packetback.Data = "piggyback".encode()
self.piggyback = True
packetback.Acknowledgement = packet.SequenceNumber + 1
self.sequence_number = random.randint(0, 2**16)
self.base_sequence_number = self.sequence_number + 1
self.expected_sequence_number = packet.SequenceNumber + 1
self.send_window_start = self.base_sequence_number
self.send_window_end = self.base_sequence_number
packetback.SequenceNumber = self.sequence_number
packetback.Type = PEEPPacket.SYNACK
packetback.updateChecksum()
self.send_packet(packetback)
self.state = PEEP_Base.HANDSHAKE
# maybe set this state to trans in case the ack in handshake gets dropped
# print('sent SYNACK')
def handle_synack(self, packet):
# print("Received synack", packet)
if packet.Acknowledgement != self.sequence_number:
return
i = 0
while i < len(self.timers):
timer = self.timers[i]
if timer._callbackArgs[0].SequenceNumber < packet.Acknowledgement:
timer.cancel()
self.timers = self.timers[:i] + self.timers[i + 1:]
i -= 1
i += 1
if packet.Data != FIELD_NOT_SET and packet.Data.decode(
) == "piggyback":
# print("synack: enable piggybacking")
self.piggyback = True
packet_to_send = PEEPPacket()
packet_to_send.Type = PEEPPacket.ACK
packet_to_send.SequenceNumber = self.sequence_number
# packet_to_send.SequenceNumber = packet.Acknowledgement
packet_to_send.Acknowledgement = packet.SequenceNumber + 1
packet_to_send.updateChecksum()
self.base_sequence_number = packet.Acknowledgement
self.expected_sequence_number = packet.SequenceNumber + 1
self.send_window_start = self.base_sequence_number
self.send_window_end = self.base_sequence_number
self.sequence_number = self.base_sequence_number
# print("Sending Back Ack")
self.send_packet(packet_to_send)
self.state = PEEP_Base.TRANS # transmission state
# Open upper layer transport
# print("connection_made to higher protocol")
self.higherProtocol().connection_made(
PEEP_Transport(self.transport, self))
def handle_ack(self, packet):
# TODO: sequence number overflow
if self.piggyback and packet.Data != FIELD_NOT_SET and len(
packet.Data) > 0:
self.handle_data(packet)
self.acknowledgement = packet.Acknowledgement
# print("ack: ", packet.Acknowledgement)
i = 0
while i < len(self.timers):
timer = self.timers[i]
if timer._callbackArgs[0].SequenceNumber < packet.Acknowledgement:
timer.cancel()
self.timers = self.timers[:i] + self.timers[i + 1:]
i -= 1
i += 1
if self.rip_timer != None:
self.rip_timer.cancel()
self.rip_timer.extend(Seconds(2))
self.rip_timer.start()
return
self.send_window_start = max(self.send_window_start,
packet.Acknowledgement)
self.send_window_data()
if self.state == PEEP_Base.TEARDOWN and self.sent_all():
self.send_rip()
self.rip_timer = Timer(Seconds(2), self.abort_connection)
self.rip_timer.start()
def handle_data(self, packet):
self.received_data.append(packet)
if packet.SequenceNumber == self.expected_sequence_number:
self.pass_data_up()
ack_packet = PEEPPacket()
if self.piggyback:
try_getting_piggyback_data = self.get_piggyback_data()
if try_getting_piggyback_data != None:
ack_packet.Data = try_getting_piggyback_data
ack_packet.SequenceNumber = self.get_piggyback_sequence_number(
)
ack_packet.Acknowledgement = self.expected_sequence_number
ack_packet.Type = PEEPPacket.ACK
ack_packet.updateChecksum()
# print("sending ack")
# print("ack: ", self.expected_sequence_number)
self.send_packet(ack_packet)
if self.state == PEEP_Base.TEARDOWN and self.received_all():
self.send_rip_ack(self.rip_sequence_number + 1)
def get_piggyback_data(self):
if self.sequence_number - self.base_sequence_number >= self.data_size:
i = self.sequence_number - self.base_sequence_number
ret = self.data[i:min(
i + self.chunk_size, self.send_window_start +
self.window_size * self.chunk_size)]
self.sequence_number += len(ret)
self.send_window_end += len(ret)
return ret
def get_piggyback_sequence_number(self):
return self.sequence_number
def pass_data_up(self):
self.received_data.sort(key=lambda packet: packet.SequenceNumber)
i = 0
while i < len(self.received_data):
packet = self.received_data[i]
if packet.SequenceNumber == self.expected_sequence_number:
self.higherProtocol().data_received(packet.Data)
self.expected_sequence_number += len(packet.Data)
self.received_data = self.received_data[:
i] + self.received_data[
i + 1:]
i -= 1
i += 1
def transmit_data(self, data):
self.data += data
self.data_size += len(data)
# print("transmitting data size: ", self.data_size)
self.send_window_data()
def send_window_data(self):
# print('send window data')
while self.send_window_end - self.send_window_start < self.window_size * self.chunk_size:
if self.sequence_number - self.base_sequence_number >= self.data_size:
# print("all bytes have been sent from me")
return
self.send_next_chunk()
# print("end send window data")
def send_next_chunk(self):
# print('send next chunk')
packet = PEEPPacket()
i = self.sequence_number - self.base_sequence_number
packet.Type = PEEPPacket.DATA
packet.SequenceNumber = self.sequence_number
packet.Data = self.data[
i:min(i + self.chunk_size, self.send_window_start +
self.window_size * self.chunk_size)]
packet.updateChecksum()
# print("sending: " , packet.SequenceNumber)
self.send_packet(packet)
self.sequence_number += len(packet.Data)
self.send_window_end += len(packet.Data)
def connection_made(self, transport):
raise NotImplementedError
def connection_lost(self, exc):
self.transport.close()
self.transport = None
asyncio.get_event_loop().stop()
def send_packet(self, packet):
# print(self, "send packet: ", packet)
self.transport.write(packet.__serialize__())
if packet.Type != PEEPPacket.SYN and packet.Type != PEEPPacket.DATA and packet.Type != PEEPPacket.RIP:
return
timer = Timer(Seconds(1), self.send_packet, packet)
self.timers.append(timer)
timer.start()
def initiate_teardown(self):
# print('teardown start')
self.state = PEEP_Base.TEARDOWN
if self.sent_all():
self.send_rip()
self.rip_timer = Timer(Seconds(2), self.abort_connection)
self.rip_timer.start()
def received_all(self):
return self.rip_sequence_number == self.expected_sequence_number
def sent_all(self):
return self.sequence_number - self.base_sequence_number >= self.data_size
def handle_rip(self, packet):
self.state = PEEP_Base.TEARDOWN
self.rip_sequence_number = packet.SequenceNumber
if self.received_all():
self.send_rip_ack(self.rip_sequence_number + 1)
def send_rip(self):
# print("send rip :", self)
rip = PEEPPacket(Type=PEEPPacket.RIP)
rip.SequenceNumber = self.sequence_number
self.sequence_number += 1
rip.updateChecksum()
self.send_packet(rip)
def send_rip_ack(self, ack):
ripack = PEEPPacket(Type=PEEPPacket.RIPACK)
ripack.Acknowledgement = ack
ripack.updateChecksum()
self.send_packet(ripack)
def handle_ripack(self, packet):
self.transport.close()
def abort_connection(self):
self.transport.close()
class PEEP(StackingProtocol):
INIT, HANDSHAKE, TRANS, TEARDOWN = [0, 1, 2, 3]
def __init__(self):
super().__init__()
self.state = PEEP.INIT
self.window_size = 100
self.chunk_size = 1024
self.transport = None
self.deserializer = None
self.base_sequence_number = None
self.sequence_number = None
self.expected_sequence_number = None
self.send_window_start = None
self.send_window_end = None
self.receive_window_start = None
self.receive_window_end = None
self.data_size = 0
self.data = bytes()
self.timers = []
self.received_data = []
self.rip_timer = None
self.rip_sequence_number = None
self.piggyback = False
self.acknowledgement = None
def data_received(self, data):
print("data received")
self.deserializer.update(data)
for packet in self.deserializer.nextPackets():
if isinstance(packet, PEEPPacket) and packet.verifyChecksum():
self.handle_packets(packet)
def handle_packets(self, packet):
packet_type = packet.Type
if packet_type == PEEPPacket.SYN and self.state == PEEP.INIT:
print('received SYN')
self.handle_syn(packet)
elif packet_type == PEEPPacket.SYNACK and self.state == PEEP.HANDSHAKE:
print('received SYNACK')
self.handle_synack(packet)
elif packet_type == PEEPPacket.ACK:
print("received ACK")
self.handle_ack(packet)
elif packet_type == PEEPPacket.DATA and (self.state == PEEP.TRANS or
self.state == PEEP.TEARDOWN):
print('received Data')
self.handle_data(packet)
elif packet_type == PEEPPacket.RIP and (self.state == PEEP.TRANS or
self.state == PEEP.TEARDOWN):
print('received RIP')
self.handle_rip(packet)
elif packet_type == PEEPPacket.RIPACK and self.state == PEEP.TEARDOWN:
print('received RIP-ACK')
self.handle_ripack()
else:
print('BAD PACKET. summary: ', packet.__repr__())
def handle_syn(self, packet):
print('checksum of SYN is correct')
packetback = PEEPPacket()
if packet.Data != FIELD_NOT_SET and packet.Data.decode(
) == "piggyback":
print("syn: enable piggybacking")
packetback.Data = "piggyback".encode()
self.piggyback = True
packetback.Acknowledgement = packet.SequenceNumber + 1
self.sequence_number = random.randint(0, 2**16)
self.base_sequence_number = self.sequence_number + 1
self.expected_sequence_number = packet.SequenceNumber + 1
self.send_window_start = self.base_sequence_number
self.send_window_end = self.base_sequence_number
packetback.SequenceNumber = self.sequence_number
packetback.Type = PEEPPacket.SYNACK
packetback.updateChecksum()
self.send_packet(packetback)
self.state = PEEP.HANDSHAKE
print('sent SYNACK')
def handle_synack(self, packet):
print("Received synack")
if packet.Data != FIELD_NOT_SET and packet.Data.decode(
) == "piggyback":
print("synack: enable piggybacking")
self.piggyback = True
packet_to_send = PEEPPacket()
packet_to_send.Type = PEEPPacket.ACK
packet_to_send.SequenceNumber = packet.Acknowledgement
packet_to_send.Acknowledgement = packet.SequenceNumber + 1
packet_to_send.updateChecksum()
self.base_sequence_number = packet.Acknowledgement
self.expected_sequence_number = packet.SequenceNumber + 1
self.send_window_start = self.base_sequence_number
self.send_window_end = self.base_sequence_number
self.sequence_number = self.base_sequence_number
print("Sending Back Ack")
self.send_packet(packet_to_send)
self.state = PEEP.TRANS # transmission state
# Open upper layer transport
print("connection_made to higher protocol")
self.higherProtocol().connection_made(
PeepTransport(self.transport, self))
def handle_ack(self, packet):
if self.piggyback and packet.Data != FIELD_NOT_SET and len(
packet.Data) > 0:
self.handle_data(packet)
self.acknowledgement = packet.Acknowledgement
print("ack: ", packet.Acknowledgement)
i = 0
while i < len(self.timers):
timer = self.timers[i]
if timer._callbackArgs[0].SequenceNumber < packet.Acknowledgement:
timer.cancel()
self.timers = self.timers[:i] + self.timers[i + 1:]
i -= 1
i += 1
if self.rip_timer is not None:
self.rip_timer.cancel()
self.rip_timer.extend(Seconds(2))
self.rip_timer.start()
return
self.send_window_start = max(self.send_window_start,
packet.Acknowledgement)
self.send_window_data()
if self.state == PEEP.TEARDOWN and self.sent_all():
self.send_rip()
self.rip_timer = Timer(Seconds(2), self.abort_connection)
self.rip_timer.start()
def handle_data(self, packet):
self.received_data.append(packet)
if packet.SequenceNumber == self.expected_sequence_number:
self.pass_data_up()
ack_packet = PEEPPacket()
if self.piggyback:
try_getting_piggyback_data = self.get_piggyback_data()
if try_getting_piggyback_data is not None:
ack_packet.Data = try_getting_piggyback_data
ack_packet.SequenceNumber = self.get_piggyback_sequence_number(
)
ack_packet.Acknowledgement = self.expected_sequence_number
ack_packet.Type = PEEPPacket.ACK
ack_packet.updateChecksum()
print("Sending ACK")
self.send_packet(ack_packet)
if self.state == PEEP.TEARDOWN and self.received_all():
self.send_rip_ack(self.rip_sequence_number + 1)
def initiate_teardown(self):
print('Start TEARDOWN')
self.state = PEEP.TEARDOWN
if self.sent_all():
self.send_rip()
self.rip_timer = Timer(Seconds(2), self.abort_connection)
self.rip_timer.start()
def received_all(self):
return self.rip_sequence_number == self.expected_sequence_number
def sent_all(self):
return self.sequence_number - self.base_sequence_number >= self.data_size
def get_piggyback_data(self):
if self.sequence_number - self.base_sequence_number >= self.data_size:
i = self.sequence_number - self.base_sequence_number
ret = self.data[i:min(
i + self.chunk_size, self.send_window_start +
self.window_size * self.chunk_size)]
self.sequence_number += len(ret)
self.send_window_end += len(ret)
return ret
def get_piggyback_sequence_number(self):
return self.sequence_number
def transmit_data(self, data):
self.data += data
self.data_size += len(data)
print("transmitting data size: ", self.data_size)
self.send_window_data()
def send_window_data(self):
print('Sending Window Data')
while self.send_window_end - self.send_window_start < self.window_size * self.chunk_size:
if self.sequence_number - self.base_sequence_number >= self.data_size:
print("Everything sent")
return
self.send_next_chunk()
def pass_data_up(self):
self.received_data.sort(
key=lambda current_packet: current_packet.SequenceNumber)
i = 0
while i < len(self.received_data):
packet = self.received_data[i]
if packet.SequenceNumber == self.expected_sequence_number:
self.higherProtocol().data_received(packet.Data)
self.expected_sequence_number += len(packet.Data)
self.received_data = self.received_data[:
i] + self.received_data[
i + 1:]
i -= 1
i += 1
def send_next_chunk(self):
print('send next chunk')
next_packet = PEEPPacket()
i = self.sequence_number - self.base_sequence_number
next_packet.Type = PEEPPacket.DATA
next_packet.SequenceNumber = self.sequence_number
next_packet.Data = self.data[
i:min(i + self.chunk_size, self.send_window_start +
self.window_size * self.chunk_size)]
next_packet.updateChecksum()
print("Now sending packet with seq number:",
next_packet.SequenceNumber)
self.send_packet(next_packet)
self.sequence_number += len(next_packet.Data)
self.send_window_end += len(next_packet.Data)
def connection_made(self, transport):
raise NotImplementedError
def connection_lost(self, exc):
self.transport.close()
self.transport = None
asyncio.get_event_loop().stop()
def send_packet(self, packet):
print(self, "send packet: ", packet)
self.transport.write(packet.__serialize__())
if packet.Type != PEEPPacket.SYN and packet.Type != PEEPPacket.DATA and packet.Type != PEEPPacket.RIP:
return
timer = Timer(Seconds(1), self.send_packet, packet)
self.timers.append(timer)
timer.start()
"""
RIP's and TEARDOWN
"""
def handle_rip(self, packet):
self.state = PEEP.TEARDOWN
self.rip_sequence_number = packet.SequenceNumber
if self.received_all():
self.send_rip_ack(self.rip_sequence_number + 1)
def send_rip(self):
print("Sending RIP")
rip_packet = PEEPPacket(Type=PEEPPacket.RIP)
rip_packet.SequenceNumber = self.sequence_number
self.sequence_number += 1
rip_packet.updateChecksum()
self.send_packet(rip_packet)
def send_rip_ack(self, ack):
print("Sending RIP ACK")
rip_ack_packet = PEEPPacket(Type=PEEPPacket.RIPACK)
rip_ack_packet.Acknowledgement = ack
rip_ack_packet.updateChecksum()
self.send_packet(rip_ack_packet)
def handle_ripack(self):
self.transport.close()
def abort_connection(self):
self.transport.close()
def send(self, pacType, PacData):
sentPacket = RIPPacket()
print("the packet type is: {}".format(pacType))
#calculateSeqAck
if "SYN" in pacType.upper() and "ACK" in pacType.upper():
print("SYN ACK")
#add Ack number
sentPacket.AckNo = self.recHand.SeqNo + 1
#add Seq
sentPacket.SeqNo = self.SequenceNo #random seq
elif "ACK" in pacType.upper():
if self.stateCon == 1:
print("1 ACK")
#add Ack number
sentPacket.AckNo = self.recHand.SeqNo + 1
#add Seq
sentPacket.SeqNo = self.sentHand.SeqNo + 1
elif "SYN" in pacType.upper():
print("SYN")
#add Ack number
sentPacket.AckNo = 0
#add Seq
sentPacket.SeqNo = self.SequenceNo #random seq
elif "DATA" in pacType.upper() or "FIN" in pacType.upper():
if self.sentHand is not None:
print("1st Packet after the Handshake")
#add Ack number
sentPacket.AckNo = 0
#add Seq
sentPacket.SeqNo = self.recHand.AckNo
#empty hands
self.recHand = None
self.sentHand = None
else:
#add Ack number
sentPacket.AckNo = 0
#add Seq
sentPacket.SeqNo = self.sentBoxData[-1][0] + len(
self.sentBoxData[-1][1].Data
) #sequence number and data length of previouse sent packet
if "FIN" in pacType.upper():
self.stateCon = 3 #FIN state
else:
print("IM NOTHING{}".format(sentPacket.AckNo))
#add Type
sentPacket.Type = pacType
#add Data
sentPacket.Data = PacData
#add checksum
sentPacket.CRC = self.hashPacket(sentPacket)
print("checksum is: {}".format(sentPacket.CRC.decode()))
print("send Type ={}, Seq= {}, ACK= {}".format(sentPacket.Type,
sentPacket.SeqNo,
sentPacket.AckNo))
#add packet to the sent list
if "DATA" in pacType.upper() or "FIN" in pacType.upper(
): #not SYN ACK since it will go to the first option
pacTimer = Timer(
Seconds(self.timeoutValue), self.timeout, sentPacket
) #self.timeoutValue = 10 :the RIP layer will wait for 10 seconds until resending the packet
pacTimer.start()
self.sentBoxData.append(
(sentPacket.SeqNo, sentPacket, pacTimer,
False)) #packet seq, packet, timer, acked or not
print("the packe is sent and next Seq number is:{}".format(
sentPacket.SeqNo + len(sentPacket.Data)))
elif "SYN" in pacType.upper(
) or "SYN" in pacType.upper() and "ACK" in pacType.upper():
print("starting a SYN or SYN ACK handshake packets timer")
self.sentHand = sentPacket
self.timHand = Timer(Seconds(self.timeoutValue), self.timeout,
self.sentHand)
self.timHand.start()
print("the timer object is: {}".format(self.timHand))
print("the packe is sent from {} and next Seq number is:{}".format(
self.identity, sentPacket.SeqNo + 1))
for seq, packet, timer, acked in self.sentBoxData:
print("sentBoxData:--- seq= {}, ack= {}, ACKED= {}".format(
seq, seq + len(packet.Data), acked))
#write packet
serPacket = sentPacket.__serialize__()
self.transport.write(sentPacket.__serialize__())
class RIP(StackingProtocol):
def __init__(self):
super().__init__()
self.transport = None
self.identity = None
self.timeoutValue = 10 #the RIP layer will wait for 10 seconds until resending the packet
self.SequenceNo = random.randrange(0, 101, 2)
self.stateCon = 0 #open server
self.sentBoxData = [
] # tupple(Sequence Number, Packet object, Timer, Acked or Not)
self.recieveBoxData = [
] # tupple(Sequence Number, Packet object, Acked or Not)
self.sentHand = None #sent message from handshake
self.recHand = None #recieved message from hanshake
self.timHand = None #timer for hanshake
self.firstCon = True #first packet flag
self.lastPacket = None #lastPacket in order in the recieve end
self._deserializer = RIPPacket.Deserializer()
# 1 = SYN, 2 = ACK, 3 = FIN 4 = DATA
def connection_made(self, transport):
print("Received a connection from {}".format(
transport.get_extra_info("peername")))
self.transport = transport
self.PassTransport = ATPtransport(self.transport, self)
self.identity = "server"
#import pdb; pdb.set_trace()
print("im here in connection made in " + self.identity)
#loop = asyncio.new_event_loop()
#asyncio.set_event_loop(loop)
def connection_lost(self, exc):
# self.send("FIN", b"")
# self.send("FIN", b"")
# self.send("FIN", b"")#third time is the charm
self.higherProtocol().connection_lost(exc)
#loop = asyncio.get_event_loop()
#loop.stop()
def data_received(self, data):
print("data_recieved start from " + self.identity)
self._deserializer.update(data)
for atppacket in self._deserializer.nextPackets():
print(atppacket.Data)
print("Got {} from the sender.".format(atppacket.Type))
#check for doublicate and hash
if self.recieveBoxData or self.recHand:
if not self.checkPacket(atppacket):
print("error packet")
return
#add to list
print("recieved Type ={}, Seq= {}, ACK= {} ".format(
atppacket.Type, atppacket.SeqNo, atppacket.AckNo))
print("And the Connection is {}".format(self.stateCon))
#end check
#states: Connecring - 0, Ongoing - 1, Established - 2, FIN - 3
if "SYN" in atppacket.Type and self.stateCon == 0: #SYN SENT and Connection is open((server))
self.handleHandshake(1, atppacket)
elif "SYN" in atppacket.Type and "ACK" in atppacket.Type and self.stateCon == 1: #SYN ACK and Connection is ongoing((client))
print("the timer object is: {}".format(self.timHand))
timerHandshake = self.timHand
self.timHand.cancel()
self.timHand = timerHandshake
print("Timer is canceled")
self.handleHandshake(2, atppacket)
elif "ACK" in atppacket.Type:
if self.stateCon == 3:
if self.sentBoxData[-1][0] + len(
self.sentBoxData[-1][1].Data) == atppacket.AckNo:
finTimer = self.sentBoxData[-1][2]
print("Timer is canceled")
finTimer.cancel()
self.sentBoxData[-1] = ((self.sentBoxData[-1][0],
self.sentBoxData[-1][1],
finTimer, True))
self.transport.close()
if self.stateCon == 1: #SYN ACK ACK and Connection is established((server))
print("the timer object is: {}".format(self.timHand))
timerHandshake = self.timHand
self.timHand.cancel()
self.timHand = timerHandshake
print("Timer is canceled")
self.handleHandshake(3, atppacket)
elif self.stateCon == 2:
self.recieveAck(atppacket)
print("ACKnowledged")
#the end of the handshake
elif "DATA" in atppacket.Type.upper(
) and self.stateCon == 2: #DATA and connection is established((serverANDclient))
print("Got a packet {}".format(atppacket))
self.recieveData(atppacket)
elif "FIN" in atppacket.Type.upper(
) and self.stateCon == 2: #FIN((server))
print("Got a FIN packet {}".format(atppacket))
self.stateCon = 3
self.connection_lost("FIN")
self.sendAck(atppacket)
for n in range(len(self.recieveBoxData)):
if self.recieveBoxData[n][
2] is False and "DATA" in self.recieveBoxData[n][
1].Type.upper(): #Acked is True
return
self.transport.close() #close when you get an Ack for the fin
else:
print("the packet has a wrong type")
if self.stateCon == 0:
self.transport.close()
def handleHandshake(self, Type, handPacket):
if Type == 1 and self.recHand is None: #SYN
self.recHand = handPacket
self.send("SYN ACK", b"") #SYN ACK
self.stateCon = 1 #Ongoing
#self.timHand.cancel()
print("The connection is {}".format(self.stateCon))
print("SYN and an ACK is sent,and the Ack number is {}".format(
handPacket.SeqNo + 1))
elif Type == 2 and self.recHand is None: #SYN ACK
if handPacket.AckNo - 1 == self.sentHand.SeqNo:
self.recHand = handPacket
self.send("ACK", b"") #SYN ACK ACK
print(
"SYN:REC and an ACK is sent. The packet state is Established. The Ack number is{}"
.format(handPacket.SeqNo + 1))
self.higherProtocol().connection_made(self.PassTransport)
self.stateCon = 2 #established with server
#self.timHand.cancel()
print("\nconnection is made with server")
self.SequenceNo = self.SequenceNo - 1 #for the first Data packet
else:
print("wrong SYN ACK")
elif Type == 3 and "SYN" in self.recHand.Type: #SYN ACK ACK
if handPacket.AckNo - 1 == self.sentHand.SeqNo:
self.recHand = handPacket
print("Got SYN ACK ACK, and the sequence number is {}".format(
handPacket.SeqNo))
print("\nconnection is made with client")
#self.timHand.cancel()
self.higherProtocol().connection_made(
self.PassTransport) #server connection
self.stateCon = 2 #established
else:
print("wrong SYN ACK ACK")
def recieveData(self, dataPacket):
#add to the list
self.recieveBoxData.append(
(dataPacket.SeqNo, dataPacket, False)) #Acked is false
#sort
self.recieveBoxData.sort()
#print the list
indexx = 0
completeFlag = True
for seq, packet, acked in self.recieveBoxData:
print("recieveBoxList:----Seq= {}, Acked= {}, Next= {}".format(
seq, acked, seq + len(packet.Data)))
if acked is False and packet.Type.upper() == "DATA":
completeFlag = False
if dataPacket.Type == "FIN" and completeFlag:
self.sendAck(dataPacket)
self.transport.close()
print("Number of Packets are: {}".format(len(self.recieveBoxData)))
#send to higher protocol and remove packets
appData = b""
index = 1
if len(self.recieveBoxData) != 1:
for index in range(len(self.recieveBoxData)):
pefIndex = index - 1
#if self.recieveBoxData[index][2] is False and self.recieveBoxData[index][0] == self.recieveBoxData[pefIndex][0] + len(self.recieveBoxData[pefIndex][1].Data):
if self.recieveBoxData[index][
2] is False and self.recieveBoxData[index][0] == (
self.recieveBoxData[pefIndex][0] +
len(self.recieveBoxData[pefIndex][1].Data)
) and self.recieveBoxData[pefIndex][2]:
#send current packet data to application
self.lastPacket = self.recieveBoxData[index][1]
self.recieveBoxData[index] = (
self.recieveBoxData[index][0],
self.recieveBoxData[index][1], True
) #because tuples dont support update, so reassigment to the index with Acked True
print(" A: This acked packet seq no is {}".format(
self.recieveBoxData[index][0]))
appData = appData + self.recieveBoxData[index][
1].Data #add data
#index = index + 1
else:
self.recieveBoxData[0] = (self.recieveBoxData[0][0],
self.recieveBoxData[0][1], True)
self.lastPacket = self.recieveBoxData[0][1]
appData = self.lastPacket.Data
#acked all data packets
self.sendAck(self.lastPacket)
#print
# #send data to the application layer
self.higherProtocol().data_received(appData)
def recieveAck(self, ackPacket):
#packetIndex = 0
for Seq, dataPacket, timer, acked in self.sentBoxData:
print(
"SentBoxList:---- for Seq= {}, Data packet ACK= {}, Acked= {} and recieved ACK is= {}"
.format(Seq, Seq + len(dataPacket.Data), acked,
ackPacket.AckNo))
if (
Seq + len(dataPacket.Data)
) == ackPacket.AckNo and acked is False: #if the ack matches the list value
print("It's a match with a sent packet= {}".format(Seq))
packetIndex = self.sentBoxData.index(
(Seq, dataPacket, timer, acked
)) + 1 #index starts with 0, while range starts with 1
print("the packet index is= {}".format(packetIndex))
for n in range(
packetIndex
): #find the timer in the dictionary using the seq number
#cancel all the timer less than the seq number
currentTimer = self.sentBoxData[n][2] #timer cancelation
currentTimer.cancel()
print("timer is canceled")
self.sentBoxData[n] = (self.sentBoxData[n][0],
self.sentBoxData[n][1],
currentTimer, True)
#self.timerDict[packetSeq] = timer.cancel()
return
def checkPacket(self, packet):
#loop dic if exist send from to last acked packet and check doublications
if "DATA" in packet.Type.upper():
for packetSeq, DataPacket, acked in self.recieveBoxData:
if packetSeq == packet.SeqNo:
if acked is True:
self.sendAck(
DataPacket) #acked data packet, resend ACK
print(
"resending ACK since the packet is already acked by the protocol"
)
return False
elif acked is False: #for doubliction Data packets
print("double Data packets is recieved")
return False
#check Hash
checkedHash = self.hashPacket(packet)
print("Checked Checksum is: " + checkedHash.decode())
if packet.CRC != checkedHash:
print("the packet has been modefied")
return False
return True
def hashPacket(self, hashPacket):
print("start hashing")
ATPpacket = RIPPacket(Type=hashPacket.Type,
SeqNo=hashPacket.SeqNo,
AckNo=hashPacket.AckNo,
CRC=b"",
Data=hashPacket.Data)
checksum = hashlib.sha256(ATPpacket.__serialize__()).hexdigest()
checksum = checksum.encode()
return checksum
def sendAck(self, packetAck):
sentAck = RIPPacket()
#add Ack number
sentAck.AckNo = packetAck.SeqNo + len(
packetAck.Data
) #sequence number and data length of previouse recieved packet
#add Seq
sentAck.SeqNo = 0
#add Type
sentAck.Type = "ACK"
#add Data
sentAck.Data = b""
#add checksum
sentAck.CRC = self.hashPacket(sentAck)
print("checksum is: {}".format(sentAck.CRC.decode()))
print("send Type ={}, Seq= {}, ACK= {}".format(sentAck.Type,
sentAck.SeqNo,
sentAck.AckNo))
#add packet to the sent list
self.transport.write(sentAck.__serialize__())
print("the ACK is sent for: {}".format(sentAck.AckNo))
def send(self, pacType, PacData):
sentPacket = RIPPacket()
print("the packet type is: {}".format(pacType))
#calculateSeqAck
if "SYN" in pacType.upper() and "ACK" in pacType.upper():
print("SYN ACK")
#add Ack number
sentPacket.AckNo = self.recHand.SeqNo + 1
#add Seq
sentPacket.SeqNo = self.SequenceNo #random seq
elif "ACK" in pacType.upper():
if self.stateCon == 1:
print("1 ACK")
#add Ack number
sentPacket.AckNo = self.recHand.SeqNo + 1
#add Seq
sentPacket.SeqNo = self.sentHand.SeqNo + 1
elif "SYN" in pacType.upper():
print("SYN")
#add Ack number
sentPacket.AckNo = 0
#add Seq
sentPacket.SeqNo = self.SequenceNo #random seq
elif "DATA" in pacType.upper() or "FIN" in pacType.upper():
if self.sentHand is not None:
print("1st Packet after the Handshake")
#add Ack number
sentPacket.AckNo = 0
#add Seq
sentPacket.SeqNo = self.recHand.AckNo
#empty hands
self.recHand = None
self.sentHand = None
else:
#add Ack number
sentPacket.AckNo = 0
#add Seq
sentPacket.SeqNo = self.sentBoxData[-1][0] + len(
self.sentBoxData[-1][1].Data
) #sequence number and data length of previouse sent packet
if "FIN" in pacType.upper():
self.stateCon = 3 #FIN state
else:
print("IM NOTHING{}".format(sentPacket.AckNo))
#add Type
sentPacket.Type = pacType
#add Data
sentPacket.Data = PacData
#add checksum
sentPacket.CRC = self.hashPacket(sentPacket)
print("checksum is: {}".format(sentPacket.CRC.decode()))
print("send Type ={}, Seq= {}, ACK= {}".format(sentPacket.Type,
sentPacket.SeqNo,
sentPacket.AckNo))
#add packet to the sent list
if "DATA" in pacType.upper() or "FIN" in pacType.upper(
): #not SYN ACK since it will go to the first option
pacTimer = Timer(
Seconds(self.timeoutValue), self.timeout, sentPacket
) #self.timeoutValue = 10 :the RIP layer will wait for 10 seconds until resending the packet
pacTimer.start()
self.sentBoxData.append(
(sentPacket.SeqNo, sentPacket, pacTimer,
False)) #packet seq, packet, timer, acked or not
print("the packe is sent and next Seq number is:{}".format(
sentPacket.SeqNo + len(sentPacket.Data)))
elif "SYN" in pacType.upper(
) or "SYN" in pacType.upper() and "ACK" in pacType.upper():
print("starting a SYN or SYN ACK handshake packets timer")
self.sentHand = sentPacket
self.timHand = Timer(Seconds(self.timeoutValue), self.timeout,
self.sentHand)
self.timHand.start()
print("the timer object is: {}".format(self.timHand))
print("the packe is sent from {} and next Seq number is:{}".format(
self.identity, sentPacket.SeqNo + 1))
for seq, packet, timer, acked in self.sentBoxData:
print("sentBoxData:--- seq= {}, ack= {}, ACKED= {}".format(
seq, seq + len(packet.Data), acked))
#write packet
serPacket = sentPacket.__serialize__()
self.transport.write(sentPacket.__serialize__())
def resend(self, resntPacket):
if "DATA" in resntPacket.Type.upper(): #start timer again
#get timer
for seq, packet, timer, acked in self.sentBoxData:
if seq == resntPacket.SeqNo:
timer.cancel()
index = self.sentBoxData.index((seq, packet, timer, acked))
pacTimer = Timer(Seconds(self.timeoutValue), self.timeout,
packet)
pacTimer.start()
self.sentBoxData[index] = (
seq, packet, pacTimer, False
) #packet seq, packet, timer, acked or not
#start timer
elif "FIN" in resntPacket.Type.upper():
currentTimer = self.sentBoxData[-1][2]
currentTimer.cancel()
currentTimer = Timer(Seconds(self.timeoutValue), self.timeout,
self.sentBoxData[-1][1])
currentTimer.start()
self.sentBoxData[-1] = (self.sentBoxData[-1][0],
self.sentBoxData[-1][1], currentTimer,
False) #last packet since its FIN
elif "ACK" in resntPacket.Type.upper():
if "SYN" in resntPacket.Type.upper():
self.timHand.cancel()
self.timHand = Timer(Seconds(self.timeoutValue), self.timeout,
self.sentHand)
self.timHand.start()
elif "SYN" in resntPacket.Type.upper():
self.stateCon = 0
print("Im here")
self.timHand.cancel()
self.timHand = Timer(Seconds(self.timeoutValue), self.timeout,
self.sentHand)
self.timHand.start()
resendPacket = RIPPacket(Type=resntPacket.Type,
SeqNo=resntPacket.SeqNo,
AckNo=resntPacket.AckNo,
CRC=resntPacket.CRC,
Data=resntPacket.Data)
print("resend packet: Type = {}, SeqNo = {}, AckNo = {},\n CRC = {}".
format(resntPacket.Type, resntPacket.SeqNo, resntPacket.AckNo,
resntPacket.CRC.decode()))
self.transport.write(resendPacket.__serialize__())
def timeout(self, timedPacket):
#import pdb; pdb.set_trace()
print("\ntimeout\nresend packet {} to {}".format(
timedPacket.SeqNo, self.identity))
self.resend(timedPacket)
