python字符串加密与反解密

在生产中会遇到很多情况是需要加密字符串的（如访问或存储密码）这些需求造就了需要字符串加密，以及反解密的问题，推荐两种方法来实现，下附代码：

#!/usr/bin/env python3

# -*- coding: utf-8 -*-

def encrypt(key, s):

    b = bytearray(str(s).encode("utf-8"))

    n = len(b)

    c = bytearray(n*2)

    j = 0

    for i in range(0, n):

        b1 = b[i]

        b2 = b1 ^ key

        c1 = b2 % 19

        c2 = b2 // 19

        c1 = c1 + 46

        c2 = c2 + 46

        c[j] = c1

        c[j+1] = c2

        j = j+2

    return c.decode("utf-8")

def decrypt(ksa, s):

    c = bytearray(str(s).encode("utf-8"))

    n = len(c)

    if n % 2 != 0:

        return ""

    n = n // 2

    b = bytearray(n)

    j = 0

    for i in range(0, n):

        c1 = c[j]

        c2 = c[j + 1]

        j = j + 2

        c1 = c1 - 46

        c2 = c2 - 46

        b2 = c2 * 19 + c1

        b1 = b2 ^ ksa

        b[i] = b1

    return b.decode("utf-8")

print(encrypt(11, 'password123'))

print(decrypt(11, '43<303>3/1.1@041'))

第二种：

from Crypto.Cipher import AES

from binascii import b2a_hex, a2b_hex

class EncryptStr(object):

    def __init__(self, key):

        self.key = key

        self.mode = AES.MODE_CBC

    def encrypt(self, text):

        cryptor = AES.new(self.key, self.mode, self.key)

        length = 16

        count = len(text)

        if (count % length != 0):

            add = length - (count % length)

        else:

            add = 0

        text = text + ('\0' * add)

        self.ciphertext = cryptor.encrypt(text)

        return b2a_hex(self.ciphertext)

    # 解密后，去掉补足的空格用strip() 去掉

    def decrypt(self, text):

        cryptor = AES.new(self.key, self.mode, self.key)

        plain_text = cryptor.decrypt(a2b_hex(text))

        return plain_text.decode('utf-8').strip('\0')

if __name__ == '__main__':

    pc = EncryptStr('keyskeyskeyskeys')  # 初始化密钥

    e = pc.encrypt("passwd123")

    d = pc.decrypt("0e0dbd0509f9eaaafd420b8a2c72cbde")

    print(e, d)