Python加密Fernet:解密过程中出错

Question

密钥以以下格式生成并持久化在env文件中：

SECRET_KEY=KG0TUB0grHz1AngJUwcsN4jcRlujde5sbzbeJ8InZsI=

def encrypt_message(message):
key = app.config['SECRET_KEY']
encoded_message = message.encode()
f = Fernet(key)
encrypted_message = f.encrypt(encoded_message)

print(encrypted_message)


def decrypt_message(encrypted_message):
key = app.config['SECRET_KEY']
f = Fernet(key)
decrypted_message = f.decrypt(encrypted_message)

print(decrypted_message.decode())

加密工作正常，没有错误。但是，在解密过程中出现以下错误：

1. 当密钥被持久化为字节字符串时：

   b'KG0TUB0grHz1AngJUwcsN4jcRlujde5sbzbeJ8InZsI='

   ValueError: Fernet key must be 32 url-safe base64-encoded bytes

2. 当密钥被持久化为字符串时

   KG0TUB0grHz1AngJUwcsN4jcRlujde5sbzbeJ8InZsI=

   TypeError: token must be bytes

Answer 1

解决方案：对密钥和消息进行编码

def decrypt_message(encrypted_message):
key = app.config['SECRET_KEY']         # KG0TUB0grHz1AngJUwcsN4jcRlujde5sbzbeJ8InZsI=
f = Fernet(key.encode())               #Encode key
decrypted_message = f.decrypt(encrypted_message.encode())  #Encode Message
print(decrypted_message.decode())