def exchange_keys_with_client(the_connection):
'''
Prompts as to whether to send keys or not
If keys are not sent, program terminates because it is
impossible to encrypt and decrypt messages
'''
try:
# wait to receive client's public key
key = the_connection.recv(8192)
key = key.split(',')
public_key_tuple = (key[0], key[1])
print '[+] Secure Chat Partner\'s Public Key Received\n'
secure_utils.display_processing_cursor("Generating And Exchanging Your Keys")
(n, e, d) = secure_utils.generate_my_keys(MODULUS_N, EXPONENT, MULTIPLICATIVE_INVERSE)
print "[+] Your TRUNCATED Public Key is (****{0},****{1})".format(str(n)[0:5], str(e)[0:5])
print "[+] Your Private Key is hidden"
public_key = str(n) + ',' + str(e)
the_connection.send(public_key)
print '[+] Your Public Key Has Been Sent To The Other Party'
private_key_tuple = (n, d)
return ((public_key_tuple), (private_key_tuple))
except Exception, e:
secure_utils.clear_screen()
print "\n\033[1;41m[+] Error connecting to server or exchanging keys\033[1;m"
raw_input("\nPress [ENTER] To Return To The Main Menu...\n")
return
pass
def display_client_menu():
'''
Displays a program menu for user to choose an option
'''
try:
# Clears the screen
secure_utils.clear_screen()
while True:
# Display My Logo
secure_utils.draw_client_logo()
print '----------------------------------\n'
print'1. Set Host Name/IP To Use\n2. Set Port Number To Use\n3. Connect To Secure Chat Session\n4. Program Information\n99. Exit Program\n'
print '----------------------------------\n'
user_chosen_option = raw_input('Enter an option >> ')
secure_utils.clear_screen()
if(user_chosen_option == '1'):
set_host_name()
elif(user_chosen_option == '2'):
set_port_number()
elif(user_chosen_option == '3'):
connect_to_server()
elif(user_chosen_option == '4'):
secure_utils.program_info()
elif(user_chosen_option == '5'):
print "Coming Soon"
elif(user_chosen_option == '6'):
print "Coming Soon"
elif(user_chosen_option == '98'):
print "Coming Soon"
elif(user_chosen_option == '99'):
break
else:
print('[--] ERROR: Invalid Option.')
raw_input("Press [ENTER] To Return To The Main Menu...\n")
secure_utils.clear_screen()
except KeyboardInterrupt:
print'[--] CTRL+C Pressed.'
except Exception, e:
print'[--] ERROR: %s' % str(e)
def read_data(self, n, d):
'''
Reads in data from client to be sent and displayed to server.
'''
try:
my_incoming_message = secure_utils.recv_end(self.my_connection) # receive incoming data
my_incoming_message = secure_utils.unpack_cipherblocks_from_transmit(my_incoming_message) # unpack the combined cipher blocks
my_incoming_message = RSA.decrypt(my_incoming_message, n, d, len([my_incoming_message])) # decrypt the cipher
while my_incoming_message.strip() != self.my_exit_code and len(my_incoming_message) > 0:
print "\r\033[1;34m<< {0}\033[1;m".format(my_incoming_message.strip())
my_incoming_message = secure_utils.recv_end(self.my_connection) # continue receiving more messages
my_incoming_message = secure_utils.unpack_cipherblocks_from_transmit(my_incoming_message) # continue unpacking the cipher blocks
my_incoming_message = RSA.decrypt(my_incoming_message, n, d, len([my_incoming_message])) # continue decrypting
# client disconnected
self.stop_write_loop()
except:
pass
def connect_to_server():
'''
Starts a connection to the server
'''
try:
secure_utils.clear_screen() # clear screen for nice output
secure_utils.draw_client_logo() #
my_client_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
my_client_socket.connect((HOST_NAME, PORT_NUMBER))
print_welcome_message(socket.gethostname(), my_client_socket.getsockname()[0])
# wait to receive server's public key . WILL RETURN NO KEYS IF SERVER HAS BANNED YOU FROM CONNECTING
(publicKeyTuple, privateKeyTuple) = exchange_keys_with_server(my_client_socket)
# checks whether server accepted or refused connection. RETURNS NONE IF BANNED
if((publicKeyTuple, privateKeyTuple) == ((None, None), (None, None))):
my_client_socket.close() # close the connection or session as you cannot carry on.
else: # begin interaction with other party.
print '\n\033[1;42m*******Type your message below and hit enter to send. Type \'EXIT\' to end conversation.*******\033[1;m\n'
ReadAndDecryptThread = ThreadManager('read', my_client_socket, publicKeyTuple, privateKeyTuple) # Thread for reading in data and decrypting
WriteAndEncryptThread = ThreadManager('write', my_client_socket, publicKeyTuple, privateKeyTuple) # Thread for writing data and encrypting
ReadAndDecryptThread.start()
WriteAndEncryptThread.start()
ReadAndDecryptThread.join()
print '[+] Your partner has left the conversation. Press any key to continue...\n'
# stop the write thread
WriteAndEncryptThread.stop_write_loop()
WriteAndEncryptThread.join()
# shut down client connection
secure_utils.display_processing_cursor('Shutting client down...')
except socket.error as socket_error:
secure_utils.clear_screen()
print socket_error[1] + "\n"
raw_input("Press [ENTER] To Return To The Main Menu...\n")
return
pass
def write_data(self, n, e):
'''
Reads in data from prompt and sending out to client
'''
try:
while self.my_continue_to_write:
my_original_message = sys.stdin.readline() # read input from user
my_outgoing_message = RSA.encrypt(my_original_message, n, e, len([my_original_message])) # encrypt the users input
my_outgoing_message = secure_utils.combine_cipherblocks_for_transmit(my_outgoing_message) + ";;" # add the ";;" delimeter. This indicates the end of a user's input. A fix for not knowing the buffer size.
self.my_connection.send(my_outgoing_message) # send out message to the user.
# check to see if my outgoing message is EXIT to quit the chat
if (my_original_message.strip() == self.my_exit_code):
self.my_connection.shutdown(socket.SHUT_RDWR)
self.my_connection.close()
self.stop_write_loop()
except:
pass
def exchange_keys_with_server(the_connection):
'''
Prompts as to whether to send keys or not
If keys are not sent, program terminates because it is
impossible to encrypt and decrypt messages
'''
try:
# wait to receive client's public public_key
secure_utils.display_processing_cursor("Generating And Exchanging Keys")
(n, e, d) = secure_utils.generate_my_keys(MODULUS_N, EXPONENT, MULTIPLICATIVE_INVERSE)
print "[+] Your TRUNCATED Public Key is (****{0},****{1})".format(str(n)[0:5], str(e)[0:5])
print "[+] Your Private Key is hidden"
generated_public_key = str(n) + ',' + str(e)
the_connection.send(generated_public_key)
print "[+] Sent Your Public Key To Your Secure Chat Partner"
message_received = the_connection.recv(8192)
if(message_received == "Send Keys"):
message_received = the_connection.recv(8192)
servers_public_key = message_received.split(",")
servers_public_key_tuple = (servers_public_key[0], servers_public_key[1])
print '[+] Server\'s Public Key Received\n'
client_private_key_tuple = (n, d)
return ((servers_public_key_tuple), (client_private_key_tuple))
else:
print "\n\033[1;41m[+] Message Received from server : {0}\033[1;m".format(message_received)
secure_utils.display_processing_cursor("Returning to main menu")
return ((None, None), (None, None))
except Exception, e:
secure_utils.clear_screen()
print "\n\033[1;41m[+] Error connecting to server or exchanging keys\033[1;m"
pass
def display_server_menu():
'''
Displays a program menu for user to choose an option
'''
try:
# Clears the screen
secure_utils.clear_screen()
while True:
# Display My Logo
secure_utils.draw_server_logo()
print '----------------------------------\n'
print'1. Change Port To Use\n2. Run Server\n3. View/Add Blocked IPs\n4. Remove Blocked IPC\n5. Program Information\n99. Exit Program\n'
print '----------------------------------\n'
user_chosen_option = raw_input('Enter an option>> ')
secure_utils.clear_screen()
if(user_chosen_option == '1'):
set_port_number()
elif(user_chosen_option == '2'):
start_server_listener()
elif(user_chosen_option == '3'):
secure_utils.add_ip_to_ban_list()
elif(user_chosen_option == '4'):
secure_utils.remove_ip_from_ban_list()
elif(user_chosen_option == '5'):
secure_utils.program_info()
elif(user_chosen_option == '99'):
break
else:
print('[--] ERROR: Invalid Option.')
raw_input("Press [ENTER] To Return To The Main Menu...\n")
secure_utils.clear_screen()
except KeyboardInterrupt:
print'[--] CTRL+C Pressed.'
except Exception, e:
print'[--] ERROR: %s' % str(e)
def start_server_listener(the_host_name=HOST_NAME, the_max_clients=MAX_CLIENTS):
'''
Starts the Secure Server, if successfully also starts listening or a client/chat partner to connect.
'''
try:
secure_utils.clear_screen() # clear screen for nice output
secure_utils.draw_server_logo() # draws logo
my_server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
my_server_socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
my_server_socket.bind(('', PORT_NUMBER))
my_server_socket.listen(the_max_clients)
print "\033[1;43m[+] The Chat Server Successfully Started\033[1;m"
print "\033[1;43m[+] Now accepting chat clients\033[1;m\n"
# Blocking call to accept connections
(my_client_connection, my_client_address) = my_server_socket.accept()
print "[+] User {0} at {1} is now connected to the server".format(socket.gethostname(), my_client_address[0])
if (my_client_address[0] in secure_utils.populated_banned_list()): # check if this user is banned from connecting, send appropriate msg
print "[+] User at {0} is banned from this server... disconnecting".format(my_client_address[0])
my_client_connection.send("Its unfortunate, but you are banned from connecting to this server")
return 0
else:
my_client_connection.send("Send Keys") # Tell other party to send their public keys.
# wait to receive client's public key
(publicKeyTuple, privateKeyTuple) = exchange_keys_with_client(my_client_connection)
print '\n\033[1;42m*******Type your message below and hit enter to send. Type \'EXIT\' to end conversation.*******\033[1;m\n'
ReadAndDecryptThread = ThreadManager('read', my_client_connection, publicKeyTuple, privateKeyTuple) # Thread for reading data and decrypting
WriteAndEcnryptThread = ThreadManager('write', my_client_connection, publicKeyTuple, privateKeyTuple) # Thread for writing data and decrypting
ReadAndDecryptThread.start() # Start the read and decrypt thread
WriteAndEcnryptThread.start() # Starts the writing and encrypting thread
# wait until client dc's
ReadAndDecryptThread.join()
print '[+] Your partner has left the conversation. Press any key to continue...\n'
# stop the write thread
WriteAndEcnryptThread.stop_write_loop()
WriteAndEcnryptThread.join()
# shut down client connection
try:
my_client_connection.shutdown(socket.SHUT_RDWR)
my_client_connection.close()
except:
# connection already closed
pass
# shut down server
secure_utils.display_processing_cursor('Shutting server down...')
my_server_socket.shutdown(socket.SHUT_RDWR)
my_server_socket.close()
return 0
except socket.error as socket_error:
print socket_error[1]
raw_input("\nPress [ENTER] To Return To The Main Menu...\n")
# print "[-] There was problem starting the server"
pass
