为我的 python 程序创建令牌系统的最简单方法是什么？ [等候接听]

Question

What is the easiest way to create a verification system for my python program that allows me to generate a token (or something similar) that is valid for a set period of time and only allows the program to run a defined number of times?

Any ideas/examples?

EDIT 11/11/2019:

This code is from "kenivia":

import cryptography
import time as ti

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


YOUR_PASSWORD_HERE = 'password'

def gen_key(p):
    '''feel like this is an overkill but imma just copy and paste this from my other thing'''
    password = p.encode()
    salt = b'rH2eMA2SYI&gUzH&QIgouxKIB*1GF908F!yC35z$2fLIFvGjxjkllh8Zztfo7n4Z'
    '''change the salt for every user and store them separately for extra security if you want
        this way even if they guessed the password they still have to brute force through 
        ^^^ this thing every time'''
    kdf = PBKDF2HMAC(
        algorithm=hashes.SHA256(),
        length=32,
        salt=salt,
        iterations=100000,
        backend=default_backend()
    )
    key = base64.urlsafe_b64encode(kdf.derive(password))
    return key



def access():
    key_from_user = input('your key: ')
    k = gen_key(YOUR_PASSWORD_HERE)
    key = Fernet(k)
    decrypted = float(str(key.decrypt(key_from_user.encode()))[2:-1])
    if ti.time()-decrypted > 60*60:
        '''if the time is over 1 hours'''
        raise AssertionError('your free trial of life has ended')
    print('you got access! and there is {} seconds of access left'.format(60*60-(ti.time()-decrypted)))


print('type 0 if you are a new user, 1 for login')
comm = input('')
if comm == '1':
    access()
elif comm == '0':
    un_encrypted_key = str(ti.time())
    k = gen_key(YOUR_PASSWORD_HERE)
    key = Fernet(k)
    saving = key.encrypt(un_encrypted_key.encode())
    print('your key:',str(saving)[2:-1])
else:
    raise Exception('no')

Many thanks for the code, but I would like to make it work only for one (or n times) within the specified time period.

How could I implement such a thing?

Answer 1

You could use a password to hash/encrypt the current timestamp and decrypt it using the same password to compare the time. You can do that with a access counter too.

This will not be secure if they have access to your password and can generate their own encrypted code

dependency: cryptography which you can install with pip

import cryptography
import time as ti

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




YOUR_PASSWORD_HERE = 'password'


def gen_key(p):
    '''feel like this is an overkill but imma just copy and paste this from my other thing'''
    password = p.encode()
    salt = b'rH2eMA2SYI&gUzH&QIgouxKIB*1GF908F!yC35z$2fLIFvGjxjkllh8Zztfo7n4Z'
    '''change the salt for every user and store them separately for extra security if you want
        this way even if they guessed the password they still have to brute force through 
        ^^^ this thing every time'''
    kdf = PBKDF2HMAC(
        algorithm=hashes.SHA256(),
        length=32,
        salt=salt,
        iterations=100000,
        backend=default_backend()
    )
    key = base64.urlsafe_b64encode(kdf.derive(password))
    return key



def access():
    key_from_user = input('your key: ')
    k = gen_key(YOUR_PASSWORD_HERE)
    key = Fernet(k)
    decrypted = float(str(key.decrypt(key_from_user.encode()))[2:-1])
    if ti.time()-decrypted > 60*60:
        '''if the time is over 1 hours'''
        raise AssertionError('your free trial of life has ended')
    print('you got access! and there is {} seconds of access left'.format(60*60-(ti.time()-decrypted)))





print('type 0 if you are a new user, 1 for login')
comm = input('')
if comm == '1':
    access()
elif comm == '0':
    un_encrypted_key = str(ti.time())
    k = gen_key(YOUR_PASSWORD_HERE)
    key = Fernet(k)
    saving = key.encrypt(un_encrypted_key.encode())
    print('your key:',str(saving)[2:-1])
else:
    raise Exception('no')