finalizando trabalho 4

trabalho4/service.py

@@ -1,10 +1,10 @@
-import socket
 from common import *
-import socket
 from AES import AESCipher
-import os
 from random import randint
+import socket
+import os
 import base64
+import time
 
 HOST = "127.0.0.1"
 PORT = SERVICE_PORT
@@ -34,6 +34,11 @@ def process_message(message):
         T_c_s = T_c_s.split("<>")
         ID_C = T_c_s[0]
         T_A = T_c_s[1]
+
+        if int(T_A) < int(time.time()):
+            print("Invalid ticket [expired]")
+            return "Invalid ticket [expired]"
+
         K_c_s = eval(T_c_s[2])
 
         M5_inner_AES = AESCipher(K_c_s)
@@ -43,10 +48,13 @@ def process_message(message):
         N3 = M5_inner[3]
 
         # generate M6
-        M6_inner = f"{randint(0, 100)}<>{N3}"
+        message = "OPEN"
+        M6_inner = f"{message}<>{N3}"
         M6_inner_AES = AESCipher(K_c_s)
         M6_inner = M6_inner_AES.encrypt(M6_inner)
 
+        print("Sending M6", f"[{message}<>{N3}]")
+
         M6 = f"{M6_inner}"
         return M6
 
@@ -57,7 +65,6 @@ def main():
         while True:
             conn, addr = s.accept()
             with conn:
-                print(f"Connected by {addr}")
                 all_data = ""
                 data = conn.recv(4096)
                 all_data += data.decode()