iniciando trab 4

trabalho4/client.py

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+from common import *
+import os
+import socket
+from AES import AESCipher
+from random import randint
+
+HOST = "127.0.0.1"
+CLIENT_ID = None
+KEY = None
+
+def register_user(username, password):
+    global CLIENT_ID, KEY
+    with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
+        s.connect((HOST, AS_PORT))
+        key = os.urandom(32)
+        message = f"register||{username},{password},{key}"
+        s.sendall(message.encode())
+        data = s.recv(4096)
+
+        data = data.decode()
+        if data == "success":
+            print("Login succeeded!")
+            CLIENT_ID = username
+            KEY = key
+
+def login(username, password):
+    global CLIENT_ID, KEY
+    with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
+        s.connect((HOST, AS_PORT))
+        message = f"login||{username},{password}"
+        s.sendall(message.encode())
+        data = s.recv(4096)
+
+        data = data.decode()
+        data = data.split(",")
+        if data[0] == "success":
+            print(f"Login succeeded!")
+            CLIENT_ID = username
+            KEY = data[1]
+
+def print_something():
+    global CLIENT_ID, KEY
+
+    if CLIENT_ID is None:
+        print("You must register or login first!")
+        return
+
+    AES = AESCipher(C_User_Key)
+
+    ID_C = CLIENT_ID
+    ID_S = "PRINTER"
+    T_R = int(input("Enter the ticket lifetime (minutes): "))
+    T_R = T_R * 60
+    N1 = randint(0, 1000000)
+
+    M2 = None
+    M4 = None
+    M6 = None
+
+    M1_inner = f"{ID_S},{T_R},{N1}"
+    M1_inner = AES.encrypt(M1_inner)
+    M1 = f"{ID_C},{M1_inner}"
+    message = f"request||{M1}"
+    with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
+        s.connect((HOST, AS_PORT))
+        print('sending m1', message)
+        s.sendall(message.encode())
+
+        data = s.recv(4096)
+        data = data.decode()
+        print('received m2', data)
+        M2 = data
+
+    '''
+    M2 = [{K_c_tgs + N_1}Kc + T_c_tgs]
+    M3 = [{ID_C + ID_S + T_R + N2}K_c_tgs + T_c_tgs]
+    '''
+    M2 = M2.split(",")
+    M2_inner = AES.decrypt(M2[0])
+    M2_inner = M2_inner.split(",")
+
+    K_c_tgs = eval(M2_inner[0])
+    N1 = M2_inner[1]
+    T_c_tgs = M2[1]
+
+    M2_AES = AESCipher(K_c_tgs)
+    N2 = randint(0, 1000000)
+
+    M3_inner = f"{ID_C},{ID_S},{T_R},{N2}"
+    M3_inner = M2_AES.encrypt(M3_inner)
+    M3 = f"{M3_inner},{T_c_tgs}"
+    with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
+        s.connect((HOST, TGS_PORT))
+        message = f"request||{M3}"
+        print('sending m3', message)
+        s.sendall(message.encode())
+
+        data = s.recv(4096)
+        data = data.decode()
+        print('received m4', data)
+        M4 = data
+
+    '''
+        M4 = [{K_c_s + T_A + N2}K_c_tgs + T_c_s]
+            T_c_s = {ID_C + T_A + K_c_s}K_s
+        M5 = [{ID_C + T_A + S_R + N3}K_c_s + T_c_s]
+    '''
+    M4 = M4.split(",")
+    M4_AES = AESCipher(K_c_tgs)
+    M4_inner = M4_AES.decrypt(M4[0])
+    M4_inner = M4_inner.split(",")
+    print('M4_inner', M4_inner)
+
+    K_c_s = eval(M4_inner[0])
+    T_A = M4_inner[1]
+    N2 = M4_inner[2]
+
+    T_c_s = M4[1]
+
+    M5_AES = AESCipher(K_c_s)
+    N3 = randint(0, 1000000)
+
+    M5_inner = f"{ID_C},{T_A},{ID_S},{N3}"
+    M5_inner = M5_AES.encrypt(M5_inner)
+    M5 = f"{M5_inner},{T_c_s}"
+
+    with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
+        s.connect((HOST, SERVICE_PORT))
+        message = f"request||{M5}"
+        print('sending m5', message)
+        s.sendall(message.encode())
+
+        data = s.recv(4096)
+        data = data.decode()
+        print('received m6', data)
+        M6 = data
+
+    '''
+    M6 = [{Resposta, N3}K_c_s]
+    '''
+    M6 = M6.split(",")
+    M6_AES = AESCipher(K_c_s)
+    M6_inner = M6_AES.decrypt(M6[0])
+    M6_inner = M6_inner.split(",")
+    resposta = M6_inner[0]
+    N3 = M6_inner[1]
+
+    print(f"Resposta: [{resposta}]")
+
+    print("Finished!!!")
+
+
+def main():
+    global CLIENT_ID
+    while True:
+        # os.system("clear")
+
+        print(f"Hello world! Logged as [{CLIENT_ID}]")
+        print("1. Register")
+        print("2. Login")
+        if CLIENT_ID is not None:
+            print("3. Print something")
+        print("0. Exit")
+
+        choice = input("Enter your choice: ")
+
+        if choice == "1":
+            username = input("Enter your username: ")
+            password = input("Enter your password: ")
+            register_user(username, password)
+        elif choice == "2":
+            username = input("Enter your username: ")
+            password = input("Enter your password: ")
+            login(username, password)
+        elif choice == "3":
+            print_something()
+        elif choice == "0":
+            break
+        else:
+            print("Invalid choice")
+
+if __name__ == "__main__":
+    main()