Python AES 加密程序返回内存错误

Question

所以我正在关注关于使用 python 实现 AES 的教程。这是一个需要实现aes的项目。以下是 Python 中的代码，它适用于小文件，但我在 1 gb 文件上尝试过，然后出现以下错误

文件“Desktop\AES\encrypting.py”，第 73 行，在 加密 = f.encrypt（编码） 文件“\Python\Python38-32\lib\site-packages\cryptography\fernet.py”，第 52 行，加密 return self._encrypt_from_parts(data, current_time, iv) _encrypt_from_parts 中的文件“\Python\Python38-32\lib\site-packages\cryptography\fernet.py”，第 58 行 padded_data = padder.update(data) + padder.finalize() 内存错误

 from cryptography.fernet import Fernet
##Fernet uses 128 bit AES IN CBC mode.

import base64
import os
from cryptography.hazmat.backends import default_backend
from cryptography.hazmat.primitives import hashes
from cryptography.hazmat.primitives.kdf.pbkdf2 import PBKDF2HMAC


##The above mentioned modules are imported to aid us in implimenting
##the AES encryption. AES encryption is asymmetric encryption method
##in which the encrtyption key used to encrypt the data
##is the same for decrypting it.UNLIKE RSA where we have two different keys


##Since we dont want to save keys everytime inside a
##file now we will create a password.Now we can take
##either password as input or
##give it inside a variable

password = input("Enter your password. make sure it is strong enough:  ")
print("\n")
text_file = input("Enter the name of text file you want to encrypt:  ")
print("\n")


salt = b'o\x10\xce\xee\xefGE=\xc4\xfe`\xd6=\xd6\xad\xde5\x0f\xa1\xdf\xa0!\x8e[\xab'
#created using os.urandom(25)

##salts are the additional data that are used to protect the
##data which might be similar fo instance there might be a possibility
##that two users can have same passwords.Thus to safeguard it we
##use salt which works as
##SHA256(salt+password)
##Thus in this way the salted value will be different for both of the
##passwords stored and it will be computationaly difficult for the hacker to
##retrieve the password.

#password = "password" #password should not be easily guessable
password22 = password.encode() #encoding the password 

kdf = PBKDF2HMAC(   #Password-based key Derivation function 2
    algorithm=hashes.SHA256(),
    length=32,
    salt=salt,
    iterations=100000,
    backend=default_backend()
)
key = base64.urlsafe_b64encode(kdf.derive(password22))
print('Following is the key generated based on your password \n')
print(key)

##This will create an encryption file for key because it is not possible for everyone to remember long keys
##and because it is very crucial for decryption therefore a file is created which will have the encryption key

file = open('encrypt.enc','wb')
file.write(key)
file.close()

##The text file which will be opened for encryption all the text contained inside of this text file will be encrypted

file = open(text_file ,'rb')

data = file.read()

encoded = data

##
##a new object of Fernet class is being created 
f = Fernet(key)

encrypted = f.encrypt(encoded)
print('\n')
print('The encrypted message is as belows \n\n')
print(encrypted)
print('\n\n')

key2 = input("Would you like to decrypt the encrypted message: y/n")

key2 =input("Enter the name of encryption file (It was created in the same directory where your code was executed under the name of encrypt.enc): ")

file = open('encrypt.enc','r')
key = file.read()
file.close()

f2 = Fernet(key)
print(key)
decrypted = f2.decrypt(encrypted)
print('The decrypted message is as belows \n')
print(decrypted)
k = input("The above message is encoded in byte types would you like to convert it into string : y/n ? ")
if (k == 'y'):
    print(decrypted.decode())
else:
    print("THANKS FOR USING OUR PROGRAM")

计划是加密硬盘驱动器，使其只能保留加密文件，否则将被删除。对于有关此功能如何加密所有 F 驱动器及其内容的任何建议，这将非常有帮助它。另外我仍然很难很好地理解这段代码，所以如果你能解释一下，那也会有帮助

Answer 1

Fernet 在返回之前缓冲所有输出，以防止在验证数据之前被滥用。但是，这种方法不适合在没有额外框架的情况下加密大文件。

如果您想加密大文件，cryptography 目前没有高级 API，但您可以使用 streaming GCM API。该 API 存在于 hazmat 中，因为它允许用户以多种方式滥用它：您可以重用 (key, nonce) 对，您可以（轻松）在解密时验证标签之前开始处理数据，等等。