python文件加密与解密的方法是什么

Python文件加密与解密的方法可以使用以下几种方式：

1. 对称加密：使用相同的密钥进行加密和解密。常见的对称加密算法有AES、DES等。可以使用cryptography库来实现对称加密，具体方法如下：

from cryptography.fernet import Fernet  # 生成密钥 key = Fernet.generate_key()  # 创建加密器 cipher = Fernet(key)  # 加密文件 with open('plain.txt', 'rb') as file:     plaintext = file.read() encrypted_text = cipher.encrypt(plaintext)  # 将加密文件写入新文件 with open('encrypted.txt', 'wb') as file:     file.write(encrypted_text)  # 解密文件 with open('encrypted.txt', 'rb') as file:     encrypted_text = file.read() decrypted_text = cipher.decrypt(encrypted_text)  # 将解密文件写入新文件 with open('decrypted.txt', 'wb') as file:     file.write(decrypted_text) 

2. 非对称加密：使用公钥进行加密，私钥进行解密。常见的非对称加密算法有RSA等。可以使用cryptography库来实现非对称加密，具体方法如下：

from cryptography.hazmat.primitives import serialization from cryptography.hazmat.primitives.asymmetric import rsa, padding from cryptography.hazmat.backends import default_backend  # 生成RSA密钥对 private_key = rsa.generate_private_key(     public_exponent=65537,     key_size=2048,     backend=default_backend() ) public_key = private_key.public_key()  # 保存私钥到文件 with open('private_key.pem', 'wb') as file:     file.write(         private_key.private_bytes(             encoding=serialization.Encoding.PEM,             format=serialization.PrivateFormat.PKCS8,             encryption_algorithm=serialization.NoEncryption()         )     )  # 保存公钥到文件 with open('public_key.pem', 'wb') as file:     file.write(         public_key.public_bytes(             encoding=serialization.Encoding.PEM,             format=serialization.PublicFormat.SubjectPublicKeyInfo         )     )  # 加密文件 with open('plain.txt', 'rb') as file:     plaintext = file.read() encrypted_text = public_key.encrypt(     plaintext,     padding.OAEP(         mgf=padding.MGF1(algorithm=hashes.SHA256()),         algorithm=hashes.SHA256(),         label=None     ) )  # 将加密文件写入新文件 with open('encrypted.txt', 'wb') as file:     file.write(encrypted_text)  # 解密文件 with open('encrypted.txt', 'rb') as file:     encrypted_text = file.read() decrypted_text = private_key.decrypt(     encrypted_text,     padding.OAEP(         mgf=padding.MGF1(algorithm=hashes.SHA256()),         algorithm=hashes.SHA256(),         label=None     ) )  # 将解密文件写入新文件 with open('decrypted.txt', 'wb') as file:     file.write(decrypted_text) 

3. 文件压缩加密：先对文件进行压缩，然后再进行加密。可以使用zipfile库进行文件压缩，再结合对称或非对称加密方法进行加密。具体方法如下：

import zipfile import shutil from cryptography.fernet import Fernet  # 压缩文件 shutil.make_archive('archive', 'zip', '.', 'plain.txt')  # 加密压缩文件 with open('archive.zip', 'rb') as file:     plaintext = file.read()      # 使用对称加密 key = Fernet.generate_key() cipher = Fernet(key) encrypted_text = cipher.encrypt(plaintext)  # 将加密文件写入新文件 with open('encrypted.zip', 'wb') as file:     file.write(encrypted_text)  # 解密文件 with open('encrypted.zip', 'rb') as file:     encrypted_text = file.read()  # 使用对称解密 decrypted_text = cipher.decrypt(encrypted_text)  # 将解密文件写入新文件 with open('decrypted.zip', 'wb') as file:     file.write(decrypted_text)  # 解压缩文件 with zipfile.ZipFile('decrypted.zip', 'r') as zip_ref:     zip_ref.extractall('.') 

注意：在加密和解密文件时，需要确保密钥的安全