Cryptography With Python 简明教程
Hacking Monoalphabetic Cipher
在本章中，您将了解单表字母加密及其使用 Python 进行破解。
In this chapter, you will learn about monoalphabetic cipher and its hacking using Python.
Monoalphabetic Cipher
单表字母加密对加密整个消息使用固定的替换。此处显示了使用带有 JSON 对象的 Python 字典的单表字母加密−
A Monoalphabetic cipher uses a fixed substitution for encrypting the entire message. A monoalphabetic cipher using a Python dictionary with JSON objects is shown here −
monoalpha_cipher = {
'a': 'm',
'b': 'n',
'c': 'b',
'd': 'v',
'e': 'c',
'f': 'x',
'g': 'z',
'h': 'a',
'i': 's',
'j': 'd',
'k': 'f',
'l': 'g',
'm': 'h',
'n': 'j',
'o': 'k',
'p': 'l',
'q': 'p',
'r': 'o',
's': 'i',
't': 'u',
'u': 'y',
'v': 't',
'w': 'r',
'x': 'e',
'y': 'w',
'z': 'q',
' ': ' ',
}借助此字典，我们可以用作为 JSON 对象中值的关联字母来加密字母。以下程序创建了一个单表字母程序，作为一个类表示，其中包括所有加密和解密的函数。
With help of this dictionary, we can encrypt the letters with the associated letters as values in JSON object. The following program creates a monoalphabetic program as a class representation which includes all the functions of encryption and decryption.
from string import letters, digits
from random import shuffle
def random_monoalpha_cipher(pool = None):
if pool is None:
pool = letters + digits
original_pool = list(pool)
shuffled_pool = list(pool)
shuffle(shuffled_pool)
return dict(zip(original_pool, shuffled_pool))
def inverse_monoalpha_cipher(monoalpha_cipher):
inverse_monoalpha = {}
for key, value in monoalpha_cipher.iteritems():
inverse_monoalpha[value] = key
return inverse_monoalpha
def encrypt_with_monoalpha(message, monoalpha_cipher):
encrypted_message = []
for letter in message:
encrypted_message.append(monoalpha_cipher.get(letter, letter))
return ''.join(encrypted_message)
def decrypt_with_monoalpha(encrypted_message, monoalpha_cipher):
return encrypt_with_monoalpha(
encrypted_message,
inverse_monoalpha_cipher(monoalpha_cipher)
)此文件稍后被调用来实现单表字母加密的加密和解密过程，如下所示−
This file is called later to implement the encryption and decryption process of Monoalphabetic cipher which is mentioned as below −
import monoalphabeticCipher as mc
cipher = mc.random_monoalpha_cipher()
print(cipher)
encrypted = mc.encrypt_with_monoalpha('Hello all you hackers out there!', cipher)
decrypted = mc.decrypt_with_monoalpha('sXGGt SGG Nt0 HSrLXFC t0U UHXFX!', cipher)
print(encrypted)
print(decrypted)