def messageReceivingService(self):
while True:
received = self.receiveData()
print "[Incoming] received raw message: " + received
# special message for exchanging Diffie Hellman keys
if(received[0] == MSG_TYPE_DH):
partial_session_key_received = int(received[1:])
if(self.mode == 'client'):
partial_session_key_generated = self.dh.partialSessionKeyGen()[0]
self.socket.sendall(MSG_TYPE_DH + str(partial_session_key_generated) + TERMINATORS)
self.total_session_key = self.dh.computeTotalSessionKey(partial_session_key_received)
self.key_estabilshment_inprogress = False
# regular messages sent by user
else:
received = received[1:]
# HMAC is first 16 bytes (32 hex digits)
receivedHmac = received[:32]
ciphertext = received[32:]
print "[Incoming] hmac received: "+ receivedHmac
print "[Incoming] ciphertext received: " + ciphertext
plaintext = CBC.decrypt(self.cipher, ciphertext)
print "[Incoming] plaintext decrypted: " + plaintext
self.console.text = self.console.text + "\nReceived: " + plaintext
generatedHmac = hmac_gen.genHmac(self.shared_secret_hash, plaintext)
print "[Incoming] hmac to compare with: " + generatedHmac
if(receivedHmac != generatedHmac):
print "ERROR: Message integrity compromised!"
def sendData(self, obj):
plaintext = self.data_to_send.text
ciphertext = CBC.encrypt(self.cipher, plaintext)
self.console.text = self.console.text + '\n' + 'Text to be sent: ' + self.data_to_send.text
hmacVal = hmac_gen.genHmac(self.shared_secret_hash, plaintext)
print "[Outgoing] encrypted ciphertext to send: " + ciphertext
print "[Outgoing] hmac value " + hmacVal
self.socket.sendall(MSG_TYPE_REGULAR + hmacVal + ciphertext + TERMINATORS)
self.data_to_send.text = ''
def sendData(self, obj):
plaintext = self.data_to_send.text
ciphertext = CBC.encrypt(self.cipher, plaintext)
self.console.text = self.console.text + '\n' + 'Text to be sent: ' + self.data_to_send.text
hmacVal = hmac_gen.genHmac(self.shared_secret_hash, plaintext)
print "[Outgoing] encrypted ciphertext to send: " + ciphertext
print "[Outgoing] hmac value " + hmacVal
self.socket.sendall(MSG_TYPE_REGULAR + hmacVal + ciphertext +
TERMINATORS)
self.data_to_send.text = ''
def messageReceivingService(self):
while True:
received = self.receiveData()
print "[Incoming] received raw message: " + received
# special message for exchanging Diffie Hellman keys
if (received[0] == MSG_TYPE_DH):
partial_session_key_received = int(received[1:])
if (self.mode == 'client'):
partial_session_key_generated = self.dh.partialSessionKeyGen(
)[0]
self.socket.sendall(MSG_TYPE_DH +
str(partial_session_key_generated) +
TERMINATORS)
self.total_session_key = self.dh.computeTotalSessionKey(
partial_session_key_received)
self.key_estabilshment_inprogress = False
# regular messages sent by user
else:
received = received[1:]
# HMAC is first 16 bytes (32 hex digits)
receivedHmac = received[:32]
ciphertext = received[32:]
print "[Incoming] hmac received: " + receivedHmac
print "[Incoming] ciphertext received: " + ciphertext
plaintext = CBC.decrypt(self.cipher, ciphertext)
print "[Incoming] plaintext decrypted: " + plaintext
self.console.text = self.console.text + "\nReceived: " + plaintext
generatedHmac = hmac_gen.genHmac(self.shared_secret_hash,
plaintext)
print "[Incoming] hmac to compare with: " + generatedHmac
if (receivedHmac != generatedHmac):
print "ERROR: Message integrity compromised!"
