I am trying a project that involves encrypting passwords using Fernet library. I have been able to enter, encrypt, and store passwords, but I keep getting the following error when I try to retrieve and decrypt the password.
Traceback (most recent call last):
File "D:\Documents\python\practiceProjects\05 passwordManager\passwordManageV2.py", line 104, in modules
pm.view()
File "D:\Documents\python\practiceProjects\05 passwordManager\passwordManageV2.py", line 82, in view
print (f'\nUser: {user}, Password: {***Fernet(self.key).decrypt(passw)***.decode()}\n')
File "C:\Users\user\AppData\Local\Programs\Python\Python312\Lib\site-packages\cryptography\fernet.py", line 84, in decrypt
timestamp, data = ***Fernet._get_unverified_token_data(token)***
File "C:\Users\user\AppData\Local\Programs\Python\Python312\Lib\site-packages\cryptography\fernet.py", line 118, in _get_unverified_token_data
raise InvalidToken
cryptography.fernet.InvalidToken<br/>
The code used to retrieve and decrypt the password is:
from cryptography.fernet import Fernet
import glob
import os
class PasswordManager:
def __init__(self):
self.key = None
self.password_file = None
def load_key (self):
with open('key.key', 'rb') as f:
self.key = f.read()
def num_file_check (self):
file = glob.glob('*.txt')
self.password_file = file[0]
if self.key == None:
self.load_key ()
def view (self):
self.num_file_check ()
with open(self.password_file, 'r') as f:
for line in f.readlines():
data = line
try:
user, passw = data.split(":")
print (f'\nUser: {user}, Password: {Fernet(self.key).decrypt(passw).decode()}\n')
except ValueError:
continue
pm = PasswordManager ()
pm.view()
I tried adding 'rb' to with open(self.password_file, 'r') as f:, as suggested. However, I received:
TypeError: a bytes-like object is required, not 'str' at user, passw = data.split(":").*
The self.key is in the form b'key' while the only the key (minus the b' ') is stored in the key.key file. Further, when I view the password file, I can see the password was encrypted before being written to the file
Site:b'gAAAAABl9KjKHh4MaltYyguafWmjwNjd35wbvfyMZMZEu-t3pabud_B7TDRIjVBaAWKkeZURYN0IGDsKD2XKkdtN2yycFrBlrw=='
The input files weren't provided, but if the password file has a Site entry like shown, the input file was written incorrectly and should not have the b'' around it which is the str() representation of a bytes object.
Below generates a fresh key.key and passwords.txt file containing the encryption key and a couple of username/password lines, respectively. The OP's code is modified to read from these files correctly:
from cryptography.fernet import Fernet
def generate_test_files():
key = Fernet.generate_key() # result is bytes object
with open('key.key', 'wb') as file: # so write in binary
file.write(key)
f = Fernet(key)
# Write as UTF-8 to support all Unicode characters for user name.
with open('passwords.txt', 'w', encoding='utf8') as file:
for user, password in (('Marco', 'contraseña'), ('马克', '密码')):
# Encrypt the UTF-8-encoded password.
# Decode the bytes object as ASCII, which is a subset of UTF-8.
# UTF-8 would work too, since the encryption is only ASCII bytes.
# The resulting Unicode object can be written to the file.
password = f.encrypt(password.encode()).decode('ascii')
print(f'{user}:{password}', file=file)
class PasswordManager:
def __init__(self):
self.load_key()
self.password_file = 'passwords.txt'
def load_key(self):
with open('key.key', 'rb') as f:
self.key = f.read()
def view(self):
with open(self.password_file, encoding='utf8') as f:
for line in f:
user, passw = line.split(':') # no b'' now to mess it up
# Encode str password to bytes and decrypt.
# Decode to print without b''.
print(f'User: {user}\nPassword: {Fernet(self.key).decrypt(passw.encode()).decode()}\n')
generate_test_files()
pm = PasswordManager()
pm.view()
Outputs:
key.key (ASCII-only):
3DZpe5WlOPFj_EQnSAXTUbOGbQvf-JKV6lILx5JIvAo=
passwords.txt (UTF-8-encoded):
Marco:gAAAAABl9PuidgvythraNfo5_JhnbIltp4g54Ej5TVPXj5Ec0PVCZellsASafgnOcdCY4In77yjaBroKgDXiRWtSygSYzTuiPw==
马克:gAAAAABl9PujHyIYpvmzeo909kt6LFT6_I1ya098vFsoRCukX48WjoqWUniVOcB0jqZ5aOr1VAXYIr_p7Q80XCYBFo3RhEUVSA==
Terminal (subject to font support):
User: Marco
Password: contraseña
User: 马克
Password: 密码