L
timerring
i love cipher
L
Who
i love cryptography
Q

 该系统的源码如下：   ##### source code    

from future import annotations
from typing import Dict
import getpass
import hashlib
import os

database: Dict[str, UserPassword] = dict()

class UserPassword:
def __init__(self, in_username, in_password_hash, in_salt):
self.username: str = in_username
self.password_hash: bytes = in_password_hash
self.salt: bytes = in_salt
self.method: str = ‘scrypt’

# define verify\_password function def verify\_password(self, password: str) -> bool:     password_ver: bytes = password.encode("utf-8")     # use the same salt     salt_ver: bytes = self.salt     # set corresponding parameters     n: int = 4     r: int = 8     p: int = 16     password_hash_ver: bytes = hashlib.scrypt(password_ver, salt=salt_ver, n=n, r=r, p=p)     # verify the hash value of the password     if password_hash_ver == self.password_hash:         return True     else:         return False 

def database_add_item(user: UserPassword) -> None:
if user.username in database:
raise Exception(‘User {}