def manage_request(self, data):
# quello che mi arriva è del tipo [OPCODE|S|C|sito|...|nonce|hash]kcs | IV
unpacked_data = utility.unpack_message(data, 4)
if(unpacked_data is None or len(unpacked_data) != 2):
utility.print_user_log(self.client_address,"Bad packet format")
return (False, 109)
encrypted_data , IV = unpacked_data
decrypted_data = utility.decrypt_AES(encrypted_data, self.session_key, IV)
if decrypted_data is None:
return (False, 102)
#print decrypted_data
decrypted_fields = utility.unpack_message(decrypted_data, 4)
if decrypted_data is None:
utility.print_user_log(self.client_address,"Bad packet format")
return (False, 109)
data_to_hash = ''.join(decrypted_fields[:-1])
hashed_data_c = decrypted_fields[-1]
hashed_data = utility.get_hash(data_to_hash)
ret = utility.secure_cmp(hashed_data_c, hashed_data)
utility.print_user_log(self.client_address,"Request: %s" % decrypted_fields[0])
if ret is False:
print hexlify(hashed_data_c)
print hexlify(hashed_data)
utility.print_user_log(self.client_address,"Different hashes")
return (False, 103)
#print fields
nonce = decrypted_fields[-2]
if nonce in self.nonces:
utility.print_user_log(self.client_address, "No fresh nonce!!")
return (False, 104)
self.nonces.append(nonce)
#print fields
#execute query
response_fields = self.execute_query(decrypted_fields[:-2]) # è una lista [:-2] tutto tranne nonce hash
response_fields.append(nonce) # aggiungo nonce alla lista
response = utility.concatenate(*response_fields)
hashed_response = utility.get_hash(response)
#print "hash,", hashed_response
#data_to_pack = utility.concatenate((response, hashed_response)) # concateno hash alla risposta
response_fields.append(hashed_response)
#print "RF: ",response_fields
packed_message = utility.pack_message(*response_fields)
#print packed_message
IV = os.urandom(16)
data_to_send = utility.encrypt_AES(packed_message, self.session_key, IV)
if data_to_send is None:
return (False, 106)
data_to_send = utility.pack_message(data_to_send, IV)
#print "DATA TO SEND \n", data_to_send
#un = utility.unpack_message(data_to_send, 4)
#print "ENC",un[0]
#print "IV", un[1]
utility.print_user_log(self.client_address, 'Response: '+ response_fields[0])
return (True, data_to_send)
def handle(self):
print "New Connection from: " + self.client_address[0], ', on port: ' , self.client_address[1]
# M1
i = 0
while(i < 4):
utility.print_user_log(self.client_address, "KEY ESTABLISHMENT PROTOCOL")
self.key_est_result = self.key_establishment_protocol()
if self.key_est_result is None:
i = i + 1
utility.print_user_log(self.client_address, "Errors during protocol number: %d" %i)
fail = utility.pack_message('FAIL')
ret = utility.send_data(self.request, fail)
if ret is False:
utility.print_user_log(self.client_address,"[ERROR] Error during sending data ")
return None
#self.request.close()
elif self.key_est_result == 201:
#utility.print_user_log(self.client_address, 'DISC')
utility.print_user_log(self.client_address, "Client Disconnected")
return None
elif self.key_est_result == 203:
i = i + 1
utility.print_user_log(self.client_address, "Errors during protocol number: %d" %i)
fail = utility.pack_message('COPY')
ret = utility.send_data(self.request, fail)
else:
utility.print_user_log(self.client_address,"Key establishment protocol has done correctly \n")
i = 0
break
if (i >= 2):
utility.print_user_log(self.client_address, "To many errors! Disconnecting...")
return None
# after return, finish() will be called
while(True):
utility.print_line()
utility.print_user_log(self.client_address, "Listening for requests...")
data = utility.recv_data(self.request, 0)
#print data
if not data or data is None:
utility.print_user_log(self.client_address, 'Client Disconnected' )
break
# after return, finish() will be called
data_to_send = self.manage_request(data)
if data_to_send[0] is False:
utility.print_user_log(self.client_address,"[ERROR] Unable to manage the request ")
ret = utility.send_data(self.request, "FAIL")
if ret is False:
utility.print_user_log(self.client_address,"[ERROR] Error during sending data ")
else:
#print data_to_send[1]
ret = utility.send_data(self.request, data_to_send[1])
if ret is False:
utility.print_user_log(self.client_address,"[ERROR] Error during sending data ")
def message_M4(self, nonce_prot_c):
utility.print_user_log(self.client_address,'Sending M4...')
hash_nonce_c = utility.get_hash(nonce_prot_c)
data_to_pack = utility.concatenate('100', self.server_ID, self.client_ID, hash_nonce_c)
hash_data = utility.get_hash(data_to_pack)
data = utility.pack_message('100', self.server_ID, self.client_ID, hash_nonce_c, hash_data)
IV = os.urandom(16)
enc_data = utility.encrypt_AES(data, self.session_key, IV)
if enc_data is None:
utility.print_user_log(self.client_address, '[ERROR] Error during encryption')
return None
data_to_send = utility.pack_message(enc_data, IV)
return data_to_send
def message_M2(self):
utility.print_user_log(self.client_address, "Sending M2..")
# generate Nonce
self.nonce_s = os.urandom(16)
# print "nonce: ", nonce_s
# read certificate
cert = utility.read_cert('server_cert_1') # server_cert_1
if cert is None:
utility.print_user_log(self.client_address,'[ERROR] Some errors occured reading the certificate')
return None
utility.print_user_log(self.client_address, 'Server certificate loaded')
data_to_send = utility.pack_message(self.server_ID, cert, self.nonce_s)
return data_to_send