def getKey(username):
"""
Returns the symmetric key to the caller
param username: User's who's folder has to be dealt with and read into
return: Symmetric key
"""
sym_key = None
if username != "admin":
# Read private key of user
folder_name = username + "_files/"
filepath = folder_name + PRIV_KEY_FILE
priv_key = serialization.load_pem_private_key(
readFile(filepath), password=None, backend=default_backend())
# Read and decrypt the encrypted symmetric key
filepath = folder_name + SHARED_KEY_FILE
sym_key = priv_key.decrypt(
readFile(filepath),
padding.OAEP(mgf=padding.MGF1(algorithm=hashes.SHA256()),
algorithm=hashes.SHA256(),
label=None))
else: # if it's the admin, it's already stored in plaintext
sym_key = readFile(ADMIN_FOLDER + "/" + SHARED_KEY_FILE)
return sym_key
def _getCurrUsersPass_():
"""
Gets the current users and passwords and returns a dictionary with the users and passwords. If file doesn't exist, it creates it with admin's details
return: dict with users array (accesed by 'users' key) and passwords array (accessed by 'passwords' key)
"""
# if file doesn't exist, create file with admin details
if not os.path.exists(USERS_FILE):
ret = {'users': ["admin"], 'passwords': [ADMIN_PASS]}
saveFile(USERS_FILE,
"admin" + USER_PASS_DELIM + ADMIN_PASS + USER_DELIM)
return ret
# get users file contents
curr_users_contents = readFile(USERS_FILE)
users_passwords = curr_users_contents.split(USER_DELIM)
ret = {'users': [], 'passwords': []} # init users and pass dict
# seperate users from passwords
for userPass in users_passwords:
if not userPass: # if string is empty we're done
break
tmpArr = userPass.split(USER_PASS_DELIM)
ret['users'].append(tmpArr[0])
ret['passwords'].append(tmpArr[1])
return ret
def __init_key_fernet__(self):
"""
Initialises a new key if it doesn't exist
return: None
"""
# read key if key exists else generate a new one
if os.path.exists(ADMIN_FOLDER + "/" + SHARED_KEY_FILE):
self.key = readFile(ADMIN_FOLDER + "/" + SHARED_KEY_FILE)
self.fernet = Fernet(self.key) # create fernet obj
else:
self.__generate_new_key__()
def upload_file(self, filename, fernet):
"""
Saves and uploads an encrypted version of the file named filename, if the file exists locally and no duplicate is on the drive
param filename: Name of the file to be uploaded
param fernet: The fernet object created in KeyManagementSystem class
return: Filename of encrypted file, if file uploaded successfully, else None
"""
# add path to filename if needed
prevFilename = filename
filename = self.normaliseFilename(filename)
# return None if file doesn't exist
if not os.path.exists(filename):
print("Error 404: File specified not found")
return None
# get the drive's main folder ID
folderID = self._get_file_ID_(DRIVE_FOLDER, DRIVE_ROOT_ID)
# Create and share folder on drive if it doesnt exist, and get folderID
if folderID == None:
folderID = self.__create_share_folder__()
print("Created shared folder on drive")
# Check if file with identical name is already on the drive
encryptedFilename = prevFilename + ENCR_EXTENSION
encryptedFileID = self._get_file_ID_(encryptedFilename, folderID)
if encryptedFileID != None: # implies there's a file identically named
print("This file is already up on the drive!")
return None
# Save encrypted file locally
plain_text = readFile(filename) # getting file contents
cipher_text = GoogleDriveAccess._encrypt_(plain_text, fernet)
normEncryptedFilename = encryptedFilename
normEncryptedFilename = self.normaliseFilename(normEncryptedFilename)
saveFile(normEncryptedFilename, cipher_text) # Saving file locally
# Upload encrypted file to google drive folder
fileToUpload = self.drive.CreateFile({"title": encryptedFilename, "parents": [{"id": folderID}]})
fileToUpload.SetContentFile(normEncryptedFilename) # set file contents
fileToUpload.Upload()
# Delete local version of encrypted file here
os.remove(normEncryptedFilename)
return encryptedFilename
def _getNewUsers_():
"""
Reads contents of the new user files and gives back an array with new usernames. Create empty file if file doesn't exist
return: Array with new usernames
"""
# Create emtpy file if it doesn't exist
if not os.path.exists(N_USERS_FILE):
saveFile(N_USERS_FILE, "")
return []
# get new user's usernames
new_users_contents = readFile(N_USERS_FILE)
new_users = new_users_contents.split(USER_DELIM)
return new_users[:-1] # ignore last empty element