比较 2 个返回 False 的哈希值，即使它们相同

Question

程序的工作原理是用户发送 2 个输入（用户输入和密码输入）。 这些将与文本文件的文件名（即用户名）和上下文（即散列密码）进行比较。密码输入被散列并返回与散列后的原始密码相同，没有差异，但是当我与 if 语句进行比较时，它返回 False。这是我的代码：

import os
import hashlib

username = "coolcat"
password = "my secret password!!"

result = hashlib.sha1(password.encode("utf-8"))

if not os.path.exists(f"{username}.txt"):
    open(f"{username}.txt", 'w').close()
with open(f"{username}.txt", "w") as file:
   file.write(str(result.digest()))

userinput = input("Your username please : ")
passwordinput = input("Your password please : ")
resulte = hashlib.sha1(passwordinput.encode("utf-8"))
print(str(resulte.digest()))
try :
    with open(f"{userinput}.txt", "r") as file:
        hashed = file.read()
    print(hashed)

    if hashed == resulte.digest():
        print("Access Granted")
    if hashed != resulte.digest():
        print("Wrong password!!")
except FileNotFoundError :
    print("Username not found!!1!")

Answer 1

您在这里使用str 打印东西是自欺欺人。问题是 hash 是 Unicode 字符串，resulte.digest() 是字节字符串。它们都打印相同，因为您使用str 函数来转换它们。如果你有字节字符串b'abc'，它包含三个字节，并且你调用str(b'abc')，你会得到一个Unicode字符串，上面写着b'abc'，但它包含6个字符：b和引号在那里。这就是区别。您编写的文件是一个包含 Unicode 字符串的 Unicode 文件，该字符串以文字字符 "b'" 开头。

解决办法是用二进制模式打开你的文件：

import os
import hashlib

username = "coolcat"
password = "my secret password!!"

result = hashlib.sha1(password.encode("utf-8"))

with open(f"{username}.txt", "wb") as file:
   file.write(result.digest())

userinput = input("Your username please : ")
passwordinput = input("Your password please : ")
resulte = hashlib.sha1(passwordinput.encode("utf-8"))
print(resulte.digest())
try :
    with open(f"{userinput}.txt", "rb") as file:
        hashed = file.read()

    if hashed == resulte.digest():
        print("Access Granted")
    if hashed != resulte.digest():
        print("Wrong password!!")
except FileNotFoundError :
    print("Username not found!!1!")

Answer 2

假设您要比较两个字符串，也将散列输出更改为字符串。除了您将字节与字符串进行比较之外，该字符串将始终返回 false。

import os
import hashlib

username = "coolcat"
password = "my secret password!!"

result = hashlib.sha1(password.encode("utf-8"))

if not os.path.exists(f"{username}.txt"):
    open(f"{username}.txt", 'w').close()
with open(f"{username}.txt", "w") as file:
   file.write(str(result.digest()))

userinput = input("Your username please : ")
passwordinput = input("Your password please : ")
resulte = hashlib.sha1(passwordinput.encode("utf-8"))
print(str(resulte.digest()))
try :
    with open(f"{userinput}.txt", "r") as file:
        hashed = str(file.read())
    print(str(hashed))

    if hashed == str(resulte.digest()):
        print("Access Granted")
    if hashed != str(resulte.digest()):
        print("Wrong password!!")
except FileNotFoundError :
    print("Username not found!!1!")