Create msg_encX.py

msg_encX.py

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+import os
+from datetime import datetime
+import random
+import math
+import base64
+import hashlib
+from Crypto import Random
+from Crypto.Cipher import AES
+import rsa
+import string
+
+
+def seedx(path , User_passcode=0, N_days=1, encryption_difficulty = 2**10):
+  try:
+    with open(path +'indx.txt') as f:
+      old_day_index = int(f.read())
+  except:
+    old_day_index = 0
+    print('no old index was found')
+  timestamp = datetime.timestamp(datetime.now())
+  #total number of days since unix time
+  days_span = timestamp/math.factorial(6)/120 + 0.1#*random.random() #first time calculate the days since unix, thae latter randomize the time zone by up to ~7 hours
+  day_index = math.floor(days_span/N_days)
+  seed = int(day_index**2 + User_passcode)
+  if day_index == old_day_index:
+      with open('prvt.pem', 'rb') as file:
+        key_data = file.read()
+        privateKey = rsa.PrivateKey.load_pkcs1(key_data)
+      with open('pblc.pem', 'rb') as file:
+          key_data = file.read()
+          publicKey = rsa.PublicKey.load_pkcs1(key_data)
+  else:
+      publicKey, privateKey = rsa.newkeys(encryption_difficulty)
+      old_day_index = day_index
+      #save in a folder
+      with open(path +'indx.txt', 'w') as f:
+        f.write(str(old_day_index))
+      with open(path +'prvt.pem', 'w') as f:
+        f.write(privateKey.save_pkcs1().decode('utf-8'))
+      with open(path +'pblc.pem', 'w') as f:
+        f.write(publicKey.save_pkcs1().decode('utf-8'))
+        
+  return {'seed':seed,'publicKey': publicKey, 'privateKey': privateKey}
+
+
+def AES_encrypt(User_message,seed, publicKey,encoding = 1, padding = 30):
+  #number conversion to encrypt non-english content
+  User_message_numbered = (int.from_bytes(bytes(User_message, 'utf-16'), "big"))
+  #padding
+  front_padding = ''.join(random.choices(string.digits, k=padding)) #string.ascii_lowercase +
+  back_padding = ''.join(random.choices(string.digits, k=padding)) #string.ascii_lowercase +
+  msg = front_padding + str(User_message_numbered) + back_padding
+  msg_len =len(msg) #total number of charachters in the msg
+  permutation_list = list(range(0,msg_len))
+  random.seed(seed)
+  random.shuffle(permutation_list)
+  shffled_msg_list = [msg[i] for i in permutation_list]
+  shffled_msg = ''.join(shffled_msg_list)
+  #print(shffled_msg)
+  encMessage = AESCipher(str(publicKey.n)).encrypt(shffled_msg)
+  if encoding == 0:
+    encMessage_int = encMessage
+  elif encoding == 1:
+    encMessage_int = encMessage.decode('utf-16')
+  else:
+    encMessage_int = int.from_bytes(encMessage, "big")
+  return encMessage_int
+
+
+class AESCipher(object):
+    def __init__(self, key):
+        self.bs = AES.block_size
+        self.key = hashlib.sha256(key.encode()).digest()
+    def encrypt(self, raw):
+        raw = self._pad(raw)
+        iv = Random.new().read(AES.block_size)
+        cipher = AES.new(self.key, AES.MODE_CBC, iv)
+        return base64.b64encode(iv + cipher.encrypt(raw.encode()))
+    def decrypt(self, enc):
+        enc = base64.b64decode(enc)
+        iv = enc[:AES.block_size]
+        cipher = AES.new(self.key, AES.MODE_CBC, iv)
+        return AESCipher._unpad(cipher.decrypt(enc[AES.block_size:])).decode('utf-8')
+    def _pad(self, s):
+        return s + (self.bs - len(s) % self.bs) * chr(self.bs - len(s) % self.bs)
+    @staticmethod
+    def _unpad(s):
+        return s[:-ord(s[len(s)-1:])]
+
+def invert_perm_list(p):
+    return [p.index(l) for l in range(len(p))]
+
+def AES_decrypt(encMessage,seed,publicKey, encoding = 1, encryption_difficulty = 2**10, padding = 30):
+  if encoding == 0:
+    encMessage_byte = encMessage
+  elif encoding == 1:
+    encMessage_byte = encMessage.encode('utf-16')
+  else:
+    encMessage_byte = encMessage.to_bytes((encMessage.bit_length() + 7) // 8, "big")
+  decMessage = AESCipher(str(publicKey.n)).decrypt(encMessage_byte)
+  decMessage_len =len(decMessage) #total number of charachters in the msg
+  permutation_list = list(range(0,decMessage_len))
+  random.seed(seed)
+  random.shuffle(permutation_list)
+  inverted_permutation_list = invert_perm_list(permutation_list)
+  recovered_list = [decMessage[i] for i in inverted_permutation_list]
+  recovered_msg_i_pad = ''.join(recovered_list)
+  recovered_msg_i = int(recovered_msg_i_pad[padding:-padding])
+  recovered_msg = recovered_msg_i.to_bytes((recovered_msg_i.bit_length() + 7) // 8, "big").decode("utf-16")
+  return recovered_msg
+
+
+
+def Encrypt_msg(User_message,user_password,path):
+    User_passcode = (int.from_bytes(bytes(str(user_password), 'utf-8'), "little"))
+    Num_dict_enc = seedx(path, User_passcode)
+    encMessage_i = AES_encrypt(User_message,Num_dict_enc['seed'], Num_dict_enc['publicKey'],encoding = 1, padding = 30)
+    #print(encMessage_i)
+    return encMessage_i
+
+
+def Decrypt_msg(encMessage,user_password,path):
+    User_passcode = (int.from_bytes(bytes(str(user_password), 'utf-8'), "little"))
+    Num_dict_enc = seedx(path, User_passcode)
+    recovered_msg = AES_decrypt(encMessage,Num_dict_enc['seed'], Num_dict_enc['publicKey'], encoding = 1, encryption_difficulty = 2**10, padding = 30)
+    #print(recovered_msg)
+    return recovered_msg