22.hashlib模块

hashlib

1.常见的几种加密方法及其使用方法：

import hashlib

# md5
hash = hashlib.md5()
hash.update(bytes(‘admin‘, encoding=‘utf-8‘))
print(hash.hexdigest())
print(hash.digest())
‘‘‘
21232f297a57a5a743894a0e4a801fc3
b‘!#/)zW\xa5\xa7C\x89J\x0eJ\x80\x1f\xc3‘
‘‘‘

# sha1
hash = hashlib.sha1()
hash.update(bytes(‘1‘, encoding=‘utf-8‘))
print(hash.hexdigest())
‘‘‘
356a192b7913b04c54574d18c28d46e6395428ab
‘‘‘

# sha256
hash = hashlib.sha256()
hash.update(bytes(‘1‘, encoding=‘utf-8‘))
print(hash.hexdigest())
‘‘‘
6b86b273ff34fce19d6b804eff5a3f5747ada4eaa22f1d49c01e52ddb7875b4b
‘‘‘

# sha384
hash = hashlib.sha384()
hash.update(bytes(‘1‘, encoding=‘utf-8‘))
print(hash.hexdigest())
‘‘‘
47f05d367b0c32e438fb63e6cf4a5f35c2aa2f90dc7543f8a41a0f95ce8a40a313ab5cf36134a2068c4c969cb50db776
‘‘‘

# sha512
hash = hashlib.sha512()
hash.update(bytes(‘1‘, encoding=‘utf-8‘))
print(hash.hexdigest())
‘‘‘
4dff4ea340f0a823f15d3f4f01ab62eae0e5da579ccb851f8db9dfe84c58b2b37b89903a740e1ee172da793a6e79d560e5f7f9bd058a12a280433ed6fa46510a
‘‘‘

　缺陷：因为每台电脑都可以进行加密，有些机器会一直运算产生密文映射库

　　　　所以以上加密算法虽然依然非常厉害，但时候存在缺陷，即：通过撞库可以反解。

　　　　因此，有必要对加密算法中添加自定义key再来做加密。

import hashlib

# md5
hash = hashlib.md5()
hash = hashlib.md5(bytes(‘自己定义的口味‘, encoding=‘utf-8‘))
hash.update(bytes(‘1‘, encoding=‘utf-8‘))
print(hash.hexdigest())
‘‘‘
0bdd27adb563c7c3198b00de20a9a972
‘‘‘

注意事项：加密算法无法直接对一个字符或者字符串加密，我们必须这些字符串转换成bytes类型再进行加密

课后拓展：将之前的用户登录程序，拓展成一个可以安全的，给用户密码加密的程序

import hashlib

def md5(arg):
    ooo = hashlib.md5(bytes("吴文", encoding=‘utf-8‘))
    ooo.update(bytes(arg, encoding=‘utf-8‘))
    return ooo.hexdigest()

def register(user, pwd):
    with open(‘db‘, ‘a‘, encoding=‘utf-8‘) as f:
        pwd = md5(pwd)
        temp = user + ‘|‘ + pwd + ‘\n‘
        f.write(temp)

def login(user, pwd):
    with open(‘db‘, ‘r‘, encoding=‘utf-8‘) as f:
        for line in f:
            user1, pwd1 = line.strip().split(‘|‘)
            if user == user1 and md5(pwd) == pwd1:
                return True

def main():
    i = input("1,登录;2,注册  :")
    if i == ‘2‘:
        user = input("用户名：")
        pwd = input("密码:")
        register(user, pwd)
    elif i == 1:
        user = input("用户名：")
        pwd = input("密码:")
        if login(user, pwd):
            print("登陆成功")
        else:
            print("登陆失败")

main()