def __handleConnectionMessages(self, state, msgObj=None):
if state == 0:
self.__state = 0
self.__connected = 0
self.__handshake = 1
self.__currSeq = random.getrandbits(32)
##print "Preparing to send a SYN Message"
##print "The sequence number I am sending is :", self.__currSeq
responseMessageBuilder = MessageData.GetMessageBuilder(PTCLMessage)
responseMessageBuilder["Hash"].setData('0')
responseMessageBuilder["MessageType"].setData("SYN")
responseMessageBuilder["MessageSeq"].setData(self.__currSeq)
responseMessageBuilder["AckSeq"].setData(0)
responseMessageBuilder["Data"].setData("")
# TODO Calculate the hash of the whole packet created above
# and fill it in the HASH field of the packet
msg_hash = self.hash_it(responseMessageBuilder)
responseMessageBuilder["Hash"].setData(msg_hash)
self.__waiting = 1
self.transport.writeMessage(responseMessageBuilder)
Timer.callLater(0.1, lambda: self.checkState(0))
elif state == 1:
# Server state where server received a SYN packet and will now send an SYNACK
if (self.__state == 3 or self.__state == 2):
##print "Already Connected"
return
##print "I have got a SYN and will now Send a SYNACK"
self.__state = 1
self.__currSeq = random.getrandbits(32)
#self.__curr_ackSeq = msgObj.MessageSeq
##print "The sequence number I got in the SYN is : ",msgObj.MessageSeq,"and the sequence number I am sending in the SYNACK is: ", self.__currSeq
if (msgObj != None):
self.__curr_ackSeq = msgObj.MessageSeq
logger.debug(
"Harsh: %s Hey! We got our SYN, setting curr_ackSeq to %d"
% (self._addr, self.__curr_ackSeq))
#Prepare and send a SYNACK Message
responseMessageBuilder = MessageData.GetMessageBuilder(
PTCLMessage)
responseMessageBuilder["Hash"].setData('0')
responseMessageBuilder["MessageType"].setData("SYNACK")
responseMessageBuilder["MessageSeq"].setData(self.__currSeq)
responseMessageBuilder["AckSeq"].setData(self.__curr_ackSeq)
responseMessageBuilder["Data"].setData("")
msg_hash = self.hash_it(responseMessageBuilder)
responseMessageBuilder["Hash"].setData(msg_hash)
self.transport.writeMessage(responseMessageBuilder)
Timer.callLater(0.1, lambda: self.checkState(1))
elif state == 2:
if (self.__state >= 2):
##print "Multiple SYNACK, Discard"
return
self.__state = 2
##print "I have got a SYNACK and will now send an ACK followed by data"
##print "The sequence number I got is : ",msgObj.MessageSeq, "and the sequence number i am sending is : ", self.__currSeq
# Extract sequence number and set state variable
self.__curr_ackSeq = msgObj.MessageSeq
logger.debug(
"Harsh: %s Hey! We got our SYNACK, setting curr_ackSeq to %d" %
(self._addr, self.__curr_ackSeq))
#Prepare and send an ACK Message
responseMessageBuilder = MessageData.GetMessageBuilder(PTCLMessage)
responseMessageBuilder["Hash"].setData('0')
responseMessageBuilder["MessageType"].setData("ACK")
responseMessageBuilder["MessageSeq"].setData(0)
responseMessageBuilder["AckSeq"].setData(msgObj.MessageSeq)
responseMessageBuilder["Data"].setData("")
#TODO Calculate the hash of the whole packet created above
# and fill it in the HASH field of the packet
msg_hash = self.hash_it(responseMessageBuilder)
responseMessageBuilder["Hash"].setData(msg_hash)
self.transport.writeMessage(responseMessageBuilder)
##print "sent an ACK , we are connected ,now sending Data:"
##print "Setting connected in client"
self.__handshake = 1
self.__connected = 1
#self.__last_contig = self.__curr_ackSeq
#set the timer
#No timer because now data has to be sent, after sending ACK you don't
# wait and start pushing data directly
##print "Sent Data"
#print "Setting hb timer on receiver"
self.__hb_timer = Timer.OneshotTimer(lambda: self.checkData())
self.__hb_timer.run(10)
Timer.callLater(0.1, lambda: self.processQueue())
self.__session_timer = Timer.OneshotTimer(
lambda: self.checkSession())
self.__session_timer.run(35)
#Timer.callLater(0.1,lambda:self.checkState(2,msgObj))
#Check if the state has looped back to the same state. Store the current time
# and check if it has changed after timeout
elif state == 3:
# Server side state, once server has received ACK from Client in response to SYNACK
self.__state = 3
# Extract sequence number, check and set state variable
##print "I have got an ACK"
#self.__currSeq = self.__currSeq +1
##print "Setting connected in server"
self.__connected = 1
self.__handshake = 1
self.__last_contig = msgObj.MessageSeq
##print "The sequence number I got is: ", msgObj.MessageSeq
#print "Setting hb timer on sender"
self.__hb_timer = Timer.OneshotTimer(lambda: self.checkData())
self.__hb_timer.run(10)
self.__session_timer = Timer.OneshotTimer(
lambda: self.checkSession())
self.__session_timer.run(35)
elif state == 5:
self.__state = 5
# Extract sequence number and set state variable
##print "I am going to send a FIN Message"
self.__currSeq = self.__currSeq + 1
#Prepare and send an FIN Message
responseMessageBuilder = MessageData.GetMessageBuilder(PTCLMessage)
responseMessageBuilder["Hash"].setData('0')
responseMessageBuilder["MessageType"].setData("FIN")
responseMessageBuilder["MessageSeq"].setData(self.__currSeq)
responseMessageBuilder["AckSeq"].setData(0)
responseMessageBuilder["Data"].setData("")
#TODO Calculate the hash of the whole packet created above
# and fill it in the HASH field of the packet
msg_hash = self.hash_it(responseMessageBuilder)
responseMessageBuilder["Hash"].setData(msg_hash)
self.transport.writeMessage(responseMessageBuilder)
#set the timer
self.__timely = Timer.callLater(0.1, lambda: self.checkState(5))
elif state == 6:
##print "I got a FIN Message and I will send a FINACK"
self.__finhandshake = 1
self.__state = 6
self.__curr_ackSeq = msgObj.MessageSeq
#Prepare and send an FINACK Message
responseMessageBuilder = MessageData.GetMessageBuilder(PTCLMessage)
responseMessageBuilder["Hash"].setData('0')
responseMessageBuilder["MessageType"].setData("FINACK")
responseMessageBuilder["MessageSeq"].setData(0)
responseMessageBuilder["AckSeq"].setData(self.__curr_ackSeq)
responseMessageBuilder["Data"].setData("")
#TODO Calculate the hash of the whole packet created above
# and fill it in the HASH field of the packet
msg_hash = self.hash_it(responseMessageBuilder)
responseMessageBuilder["Hash"].setData(msg_hash)
##print "Sending FINACK now: "
self.transport.writeMessage(responseMessageBuilder)
Timer.callLater(
0.1, lambda: self.getHigherProtocol().connectionLost(
"Received FIN"))
self.transport.loseConnection()
self.__connected = 0
elif state == 7:
###print "I am suppose to send an ACK for data received:"
responseMessageBuilder = MessageData.GetMessageBuilder(PTCLMessage)
responseMessageBuilder["Hash"].setData('0')
responseMessageBuilder["MessageType"].setData("ACK")
responseMessageBuilder["MessageSeq"].setData(0)
logger.info("Harsh: %s Sending ACK with ACK Sequence %d" %
(self._addr, self.__curr_ackSeq))
responseMessageBuilder["AckSeq"].setData(self.__curr_ackSeq)
# There is no data being piggy bagged on the ACK , if required put the data here from the
# buffer where it is stored.
responseMessageBuilder["Data"].setData("")
responseMessageBuilder["Hash"].setData(
self.hash_it(responseMessageBuilder))
self.transport.writeMessage(responseMessageBuilder)
elif state == 8:
self.__state = 8
self.__currSeq = 0
self.__curr_ackSeq = 0
##print "I received a FINACK - Trying to terminate connection"
##print "dataList and rcvWindow are both empty, safe to terminate, connectionLost() called"
Timer.callLater(
0.2, lambda: self.getHigherProtocol().connectionLost(
"Received FINACK"))
self.transport.loseConnection()
if self.__timely:
self.__timely.cancel()
self.__connected = 0
else:
pass