使用Python实现AES加密解密

(1)对于AES加密解密相关知识的介绍,可以参考下面的博文,里面介绍的很详细;

AES加密解密详解

(2)实现的功能就是输入0-16个字符,然后经过AES的加密解密最后可以得到原先的输入,运行的结果如下


开始的字符串就是输入的明文,第一个矩阵,是明文对应的状态矩阵,下面的字典是得到的经过扩展后的密钥,再下面的矩阵是经过加密之后的矩阵,最后的矩阵就是解密之后的矩阵,最后的输出就是还原的明文,可以发现AES加密解密的过程没毛病。

(3)字节代换:输入输出都是十六进制的矩阵格式,define_byte_subdtitution()函数的功能是完成字节代换,首先使用hex_to_int_number()函数将十六进制数转换为对应的十进制数,然后到S盒与逆S盒中进行字节的代换,这个过程中比较麻烦的是S盒与逆S盒数据的输入,好家伙。而逆字节代换就是使用逆S盒;

(4)行移位:输入输出都是十六进制的矩阵格式,define_line_shift()函数是在加密时使用的,define_line_inverse_shift()函数是在解密时使用的;

(5)列混合:输入是使用的十进制矩阵,输出是十六进制的矩阵,在列混合前为了方便操作,使用函数define_column_rotation()将矩阵进行了行列交换位置,然后对每一个数据进行操作,get_2()函数是实现与2相乘的结果,在加密与解密中会多次用到,XOR()函数实现两个二进制数的异或操作,在逆列混合中就是左乘的矩阵有所不同;

(6)轮密钥加:输入输出都是十六进制的矩阵格式,在进行加密解密之前先将密钥进行扩展,得到加解密过程中使用的所有的密钥,并放在一个字典中,然后在加密解密过程中使用相应的密钥即可,get_extend_key()函数得到扩展密钥,一共有44个字,每次在进行轮密钥加时使用4个字,get_round_key_plus()函数实现轮密钥加的操作,就是进行异或操作;

(7)最后就是实现加密与解密的详细的过程,其中的九轮是一样的,最后一轮单独拿出来进行处理即可,主要的问题可能会出现在一些小细节的处理上,像我遇到的就是在解密中控制使用轮密钥的变量k,开始把k放在了10轮循环中,导致k的值一直是初值没有改变,所以加密解密没有成功,之后我就在各个步骤中一个一个的测试,发现字节代换,行移位,列混合,甚至轮密钥加单独使用的时候都可以实现还原明文,然后,我又仔细的检查了下,加密解密的函数,终于发现了这个问题,问题虽小,但是影响很大,使得整个的程序没有得到预想的结果,幸好最后的结局还算满意,就是写的代码有点乱,自己也懒得改了,希望有大佬要是有什么意见,可以随时交流。

import random

def get_matrix_of_clear_number(clear_number):
	#得到输入数据对应的十六进制ASCII码矩阵
	dir = {0:[], 1:[], 2:[], 3:[]}
	length = len(clear_number)
	for i in range(length):
		number = ord(clear_number[i])
		dir[i % 4].append(hex(number))
	return dir
		
def get_matrix_of_cipher_number():
	#得到随机生成的密钥的十六进制矩阵	
	dir_number = {10:"A", 11:"B", 12:"C", 13:"D", 14:"E", 15:"F"}
	string = ''
	for i in range(16):
		number = int(random.random() * 16)
		if(number >= 10):
			number = dir_number[number]
		else:
			number = str(number)
		string = string + number

	dir = get_matrix_of_clear_number(string)
	return dir
	
def define_S_box(fir_num, last_num):
	#定义S盒
	dir = {
		0:['0x63', '0x7c', '0x77', '0x7b', '0xf2', '0x6b', '0x6f', '0xc5', '0x30', '0x01', '0x67', '0x2b', 
		'0xfe', '0xd7', '0xab', '0x76'],
		1:['0xca', '0x82', '0xc9', '0x7d', '0xfa', '0x59', '0x47', '0xf0', '0xad', '0xd4', '0xa2', '0xaf',  '0x9c', '0xa4', '0x72', '0xc0'],
		2:['0xb7', '0xfd', '0x93', '0x26', '0x36', '0x3f', '0xf7', '0xcc', '0x34', '0xa5', '0xe5', '0xf1',   '0x71', '0xd8', '0x31', '0x15'],
		3:['0x04', '0xc7', '0x23', '0xc3', '0x18', '0x96', '0x05', '0x9a', '0x07', '0x12', '0x80', '0xe2',  '0xeb', '0x27', '0xb2', '0x75'],
		4:['0x09', '0x83', '0x2c', '0x1a', '0x1b', '0x6e', '0x5a', '0xa0', '0x52', '0x3b', '0xd6', '0xb3',  '0x29', '0xe3', '0x2f', '0x84'],
		5:['0x53', '0xd1', '0x00', '0xed', '0x20', '0xfc', '0xb1', '0x5b', '0x6a', '0xcb', '0xbe', '0x39',  '0x4a', '0x4c', '0x58', '0xcf'],
		6:['0xd0', '0xef', '0xaa', '0xfb', '0x43', '0x4d', '0x33', '0x85', '0x45', '0xf9', '0x02', '0x7f', 
		'0x50', '0x3c', '0x9f', '0xa8'],
		7:['0x51', '0xa3', '0x40', '0x8f', '0x92', '0x9d', '0x38', '0xf5', '0xbc', '0xb6', '0xda', '0x21', 
		'0x10', '0xff', '0xf3', '0xd2'],
		8:['0xcd', '0x0c', '0x13', '0xec', '0x5f', '0x97', '0x44', '0x17', '0xc4', '0xa7', '0x7e', '0x3d', 
		'0x64', '0x5d', '0x19', '0x73'],
		9:['0x60', '0x81', '0x4f', '0xdc', '0x22', '0x2a', '0x90', '0x88', '0x46', '0xee', '0xb8', '0x14', 
		'0xde', '0x5e', '0x0b', '0xdb'],
		10:['0xe0', '0x32', '0x3a', '0x0a', '0x49', '0x06', '0x24', '0x5c', '0xc2', '0xd3', '0xac', '0x62', '0x91', '0x95', '0xe4', '0x79'],
		11:['0xe7', '0xc8', '0x37', '0x6d', '0x8d', '0xd5', '0x4e', '0xa9', '0x6c', '0x56', '0xf4', '0xea', '0x65', '0x7a', '0xae', '0x08'],
		12:['0xba', '0x78', '0x25', '0x2e', '0x1c', '0xa6', '0xb4', '0xc6', '0xe8', '0xdd', '0x74', '0x1f', '0x4b', '0xbd', '0x8b', '0x8a'],
		13:['0x70', '0x3e', '0xb5', '0x66', '0x48', '0x03', '0xf6', '0x0e', '0x61', '0x35', '0x57', '0xb9', '0x86', '0xc1', '0x1d', '0x9e'],
		14:['0xe1', '0xf8', '0x98', '0x11', '0x69', '0xd9', '0x8e', '0x94', '0x9b', '0x1e', '0x87', '0xe9', '0xce', '0x55', '0x28', '0xdf'],
		15:['0x8c', '0xa1', '0x89', '0x0d', '0xbf', '0xe6', '0x42', '0x68', '0x41', '0x99', '0x2d', '0x0f', '0xb0', '0x54', '0xbb', '0x16']
	}	
	return (dir[fir_num][last_num])
	
def define_inverse_S_box(fir_num, last_num):
	#定义S逆盒
	dir = {
		0:['0x52', '0x09', '0x6a', '0xd5', '0x30', '0x36', '0xa5', '0x38', '0xbf', '0x40', '0xa3', '0x9e', '0x81', '0xf3', '0xd7', '0xfb'],
		1:['0x7c', '0xe3', '0x39', '0x82', '0x9b', '0x2f', '0xff', '0x87', '0x34', '0x8e', '0x43', '0x44', '0xc4', '0xde', '0xe9', '0xcb'],
		2:['0x54', '0x7b', '0x94', '0x32', '0xa6', '0xc2', '0x23', '0x3d', '0xee', '0x4c', '0x95', '0x0b', '0x42', '0xfa', '0xc3', '0x4e'],
		3:['0x08', '0x2e', '0xa1', '0x66', '0x28', '0xd9', '0x24', '0xb2', '0x76', '0x5b', '0xa2', '0x49', '0x6d', '0x8b', '0xd1', '0x25'],
		4:['0x72', '0xf8', '0xf6', '0x64', '0x86', '0x68', '0x98', '0x16', '0xd4', '0xa4', '0x5c', '0xcc', '0x5d', '0x65', '0xb6', '0x92'],
		5:['0x6c', '0x70', '0x48', '0x50', '0xfd', '0xed', '0xb9', '0xda', '0x5e', '0x15', '0x46', '0x57', '0xa7', '0x8d', '0x9d', '0x84'],
		6:['0x90', '0xd8', '0xab', '0x00', '0x8c', '0xbc', '0xd3', '0x0a', '0xf7', '0xe4', '0x58', '0x05', '0xb8', '0xb3', '0x45', '0x06'],
		7:['0xd0', '0x2c', '0x1e', '0x8f', '0xca', '0x3f', '0x0f', '0x02', '0xc1', '0xaf', '0xbd', '0x03', '0x01', '0x13', '0x8a', '0x6b'],
		8:['0x3a', '0x91', '0x11', '0x41', '0x4f', '0x67', '0xdc', '0xea', '0x97', '0xf2', '0xcf', '0xce', '0xf0', '0xb4', '0xe6', '0x73'],
		9:['0x96', '0xac', '0x74', '0x22', '0xe7', '0xad', '0x35', '0x85', '0xe2', '0xf9', '0x37', '0xe8', '0x1c', '0x75', '0xdf', '0x6e'],
		10:['0x47', '0xf1', '0x1a', '0x71', '0x1d', '0x29', '0xc5', '0x89', '0x6f', '0xb7', '0x62', '0x0e', '0xaa', '0x18', '0xbe', '0x1b'],
		11:['0xfc', '0x56', '0x3e', '0x4b', '0xc6', '0xd2', '0x79', '0x20', '0x9a', '0xdb', '0xc0', '0xfe', '0x78', '0xcd', '0x5a', '0xf4'],
		12:['0x1f', '0xdd', '0xa8', '0x33', '0x88', '0x07', '0xc7', '0x31', '0xb1', '0x12', '0x10', '0x59', '0x27', '0x80', '0xec', '0x5f'],
		13:['0x60', '0x51', '0x7f', '0xa9', '0x19', '0xb5', '0x4a', '0x0d', '0x2d', '0xe5', '0x7a', '0x9f', '0x93', '0xc9', '0x9c', '0xef'],
		14:['0xa0', '0xe0', '0x3b', '0x4d', '0xae', '0x2a', '0xf5', '0xb0', '0xc8', '0xeb', '0xbb', '0x3c', '0x83', '0x53', '0x99', '0x61'],
		15:['0x17', '0x2b', '0x04', '0x7e', '0xba', '0x77', '0xd6', '0x26', '0xe1', '0x69', '0x14', '0x63', '0x55', '0x21', '0x0c', '0x7d']
		
	}	
	return (dir[fir_num][last_num])

def hex_to_int_number(hex_num, flag):
	#十六进制矩阵转换为十进制矩阵
	number = int(hex_num, 16)
	int_num = number // 16
	int_re = number % 16
	if flag == 1:
		my_number = define_S_box(int_num, int_re)
	else:
		my_number = define_inverse_S_box(int_num, int_re)
	return my_number	

def define_byte_subdtitution(dir_new_number, flag):
	#定义字节代换
	dir_1 = {0:[], 1:[], 2:[], 3:[]}
	for j in range(4):
		list_new = []
		list = dir_new_number[j]
		for k in range(4):		
			new_num = hex_to_int_number(list[k], flag)
			list_new.append(new_num)
		dir_1[j] = list_new
	return dir_1

	
def define_line_shift(dir_clear_number):
	#进行行移位操作
	for i in range(4):
		my_list = []
		list = dir_clear_number[i]
		for j in range(4):
			my_list.append(list[(j + i) % 4])
		dir_clear_number[i] = my_list
	return dir_clear_number
	
def define_line_inverse_shift(dir_clear_number):
	#进行行移位的逆操作
	for i in range(4):
		my_list = []
		list = dir_clear_number[i]
		for j in range(4):
			my_list.append(list[(j + 4 - i) % 4])
		dir_clear_number[i] = my_list
	return dir_clear_number

	
def XOR(string_1, string_2):
	#得到异或后的十进制结果	
	decimal_result = 0
	for i in range(8):
		if string_1[i] != string_2[i]:
			decimal_result += 2 ** (7 - i)
	
	return decimal_result

def dex_to_int(string):
	#得到数据二进制到十进制的转换
	my_result = 0
	for k in range(8):		
		if string[k] == '1':
			my_result += 2 ** (7 - k)
	return my_result	
			
def get_2(last_num):
	#得到列混合中乘以2的结果	
	last_num_copy = last_num
	last_num_copy = bin(last_num_copy)[2:].rjust(8, '0')
	judge_num = bin(last_num)[2:]	
	judge_num = last_num_copy[0]
	last_num_copy = last_num_copy[1:]
	last_num_copy += '0'
	
	if judge_num == '1':
		string_judge = '00011011'	
		last_num_copy = bin(XOR(string_judge, last_num_copy))[2:].rjust(8, '0')	
	return last_num_copy
	
def define_column_rotation(dir_clear_number_copy):
	#在列混合中先将列进行旋转
	dir_clear_number = {0:[], 1:[], 2:[], 3:[]}
	for key, num in dir_clear_number_copy.items():
		list = num	
		for i  in range(4):
			dir_clear_number[i].append(list[i])	
	return dir_clear_number
	
def define_column_hybrid(dir_clear_number_copy):
	#进行列混合操作,得到对应的十六进制的矩阵		
	dir_matrix = {
		0:[2, 3, 1, 1],
		1:[1, 2, 3, 1],
		2:[1, 1, 2, 3],
		3:[3, 1, 1, 2]
	}
	dir_clear_number = define_column_rotation(dir_clear_number_copy)	
	dir_new_clear_number = {0:[], 1:[], 2:[], 3:[]}
	
	for i in range(4):	
		list_matrix = dir_matrix[i]
		list = []
		for j in range(4):		
			list_num = dir_clear_number[j]	
			string = ''		
			my_string  = '00000000'

			for k in range(4):
				if list_matrix[k] == 2:
					string = get_2(list_num[k])
				if list_matrix[k] == 3:
					string = get_2(list_num[k])
					list_num_copy = bin(list_num[k])[2:].rjust(8, '0')
					string = bin(XOR(string, list_num_copy))[2:].rjust(8, '0')
				if list_matrix[k] == 1:
					string = bin(list_num[k])[2:].rjust(8, '0')	
				my_string = bin(XOR(my_string, string))[2:].rjust(8, '0')
			my_result = dex_to_int(my_string)
			list.append(hex(my_result))
			dir_new_clear_number[i] = list
	return dir_new_clear_number

def define_inverse_column_hybrid(dir_clear_number_copy):
	#进行列混合逆操作,得到对应的十六进制的矩阵	
	dir_matrix = {
		0:[14, 11, 13, 9],
		1:[9, 14, 11, 13],
		2:[13, 9, 14, 11],
		3:[11, 13, 9, 14]
	}
	dir_clear_number = define_column_rotation(dir_clear_number_copy)
	
	dir_new_clear_number = {0:[], 1:[], 2:[], 3:[]}
	for i in range(4):	
		list_matrix = dir_matrix[i]
		list = []
		for j in range(4):		
			list_num = dir_clear_number[j]	
			string = ''		
			my_string  = '00000000'
			my_result = 0	
						
			for k in range(4):
				if list_matrix[k] == 14:
					string_1 = get_2(list_num[k])
					string_1_int = dex_to_int(string_1)
					string_2 = get_2(string_1_int)
					string_2_int = dex_to_int(string_2)
					string_3 = get_2(string_2_int)
					string = bin(XOR(string_2, string_1))[2:].rjust(8, '0')
					string = bin(XOR(string, string_3))[2:].rjust(8, '0')
				if list_matrix[k] == 11:
					string_1 = get_2(list_num[k])
					string_1_int = dex_to_int(string_1)
					string_2 = get_2(string_1_int)
					string_2_int = dex_to_int(string_2)
					string_3 = get_2(string_2_int)
					
					string_4 = bin(list_num[k])[2:].rjust(8, '0')	
					string = bin(XOR(string_3, string_1))[2:].rjust(8, '0')
					string = bin(XOR(string, string_4))[2:].rjust(8, '0')
					
				if list_matrix[k] == 13:
					string_1 = get_2(list_num[k])
					string_1_int = dex_to_int(string_1)
					string_2 = get_2(string_1_int)
					string_2_int = dex_to_int(string_2)
					string_3 = get_2(string_2_int)
					
					string_4 = bin(list_num[k])[2:].rjust(8, '0')	
					string = bin(XOR(string_3, string_2))[2:].rjust(8, '0')
					string = bin(XOR(string, string_4))[2:].rjust(8, '0')
				if list_matrix[k] == 9:
					string_1 = get_2(list_num[k])
					string_1_int = dex_to_int(string_1)
					string_2 = get_2(string_1_int)
					string_2_int = dex_to_int(string_2)
					string_3 = get_2(string_2_int)
					
					string_4 = bin(list_num[k])[2:].rjust(8, '0')
					string = bin(XOR(string_3, string_4))[2:].rjust(8, '0')
	
				my_string = bin(XOR(my_string, string))[2:].rjust(8, '0')
		
			my_result = dex_to_int(my_string)
			list.append(hex(my_result))
			dir_new_clear_number[i] = list
	return dir_new_clear_number
	
def hex_to_int(dir_clear_number):
	#将十六进制的矩阵转换为十进制的矩阵
	dir_clear_number_copy = {0:[], 1:[], 2:[], 3:[]}
	for key, num in dir_clear_number.items():
		list = []
		for i in range(4):
			list.append(int(num[i], 16))
		dir_clear_number_copy[key] = list	
	return dir_clear_number_copy
	
def get_4_double(i_num, num, dir_key):
	#在轮密钥加中 ,得到4的倍数
	dir_R = {
		1: ['01','00', '00', '00'],
		2: ['02', '00', '00', '00'],
		3: ['04', '00', '00', '00'],
		4: ['08', '00', '00', '00'],
		5: ['10', '00', '00', '00'],
		6: ['20', '00', '00', '00'],
		7: ['40', '00', '00', '00'],
		8: ['80', '00', '00', '00'],
		9: ['1B', '00', '00', '00'],
		10: ['36', '00', '00', '00']
		}
	list_R = dir_R[i_num // 4 + 1]	
	list = []
	list_dir = dir_key[num - 1]
	#print(list_dir)
	for i in range(4):
		list.append(list_dir[(i + 1) % 4])
	
	for i in range(4):	
		list_int = int(list[i], 16)
		line_number = list_int // 16
		row_number = list_int % 16	
	
		list[i] = define_S_box(line_number, row_number)
	list_new = []
	for i in range(4):		
		num_1 = int(list_R[i], 16)
		num_2 = int(list[i], 16)
		string_1 = bin(num_1)[2:].rjust(8, '0')
		string_2 = bin(num_2)[2:].rjust(8, '0')
		string = XOR(string_1, string_2)
		list_new.append(hex(string))
	return list_new
	
def get_extend_key(dir_cipher_number):
	#得到扩展密钥
	dir_cipher_number_copy = dir_cipher_number
	
	dir_key = {}
	for i in range(44):
		dir_key[i] = []
		
	for j in range(4):
		list = []
		list_dir = dir_cipher_number_copy[j]
		for k in range(4):
			list.append(list_dir[k])
		dir_key[j] = list
		
	for i in range(40):
		num = 4 + i
		if num % 4 == 0:
			list_T = get_4_double(i, num, dir_key)
		else:
			list_T = dir_key[num - 1]

		list_key = dir_key[num - 4]
		list = []
		for j in range(4):
			string_1 = bin(int(list_T[j], 16))[2:].rjust(8, '0')
			string_2 = bin(int(list_key[j], 16))[2:].rjust(8, '0')
			string = XOR(string_1, string_2)
			list.append(hex(string))
		dir_key[4 + i] = list
	return dir_key
	
def get_round_key_plus(clear_number, dir_key_extend):
	#进行轮密钥加的操作
	dir_new_number = {0:[], 1:[], 2:[], 3:[]}
	for i in range(4):
		list_number = clear_number[i]
		list_key = dir_key_extend[i]
		list = []
		for j in range(4):
			number = int(list_number[j], 16)
			key = int(list_key[j], 16)
			string_num = bin(number)[2:].rjust(8, '0')
			string_key = bin(key)[2:].rjust(8, '0')
			result_int = XOR(string_num, string_key)
			list.append(hex(result_int))
		dir_new_number[i] = list
	return dir_new_number
	
def define_encryption(clear_number, dir_key_extend):
	#对明文进行轮密钥加
	dir_new_number = get_round_key_plus(clear_number, dir_key_extend)
	
	#进行中间的十轮运算
	for i in range(10):		
		num = 4 * (i + 1)
		dir_key_extend_part = {}
		
		for j in range(4):
			dir_key_extend_part[j] = dir_key_extend[num]
			num += 1
		
		#字节代换
		dir_1 = define_byte_subdtitution(dir_new_number, 1)
		
		#行移位
		dir_1 = define_line_shift(dir_1)
		
		#定义列混合操作
		if i != 9:
			dir_1 = hex_to_int(dir_1)
			dir_1 = define_column_hybrid(dir_1)
		
		#定义轮密钥加
		dir_1 = get_round_key_plus(dir_1, dir_key_extend_part)
		dir_new_number = dir_1
		
	return dir_new_number
	
def define_decryption(clear_number, dir_key_extend):
	#对密文进行轮密钥加
	dir_key_extend_part = {
			0: dir_key_extend[40],
			1: dir_key_extend[41],
			2: dir_key_extend[42],
			3: dir_key_extend[43]
			}
	dir_new_number = get_round_key_plus(clear_number, dir_key_extend_part)
	
	#进行中间的十轮运算
	k = 9
	for i in range(10):			
		num = 4 * k
		dir_key_extend_part = {}
		for j in range(4):
			dir_key_extend_part[j] = dir_key_extend[num]
			num += 1
		k -= 1
		
		#逆行移位
		dir_1 = define_line_inverse_shift(dir_new_number)
		
		#逆字节代换
		dir_1 = define_byte_subdtitution(dir_1, 0)
			
		#定义轮密钥加
		dir_1 = get_round_key_plus(dir_1, dir_key_extend_part)
		dir_new_number = dir_1
	
		#定义逆列混合操作
		if i != 9:
			dir_1 = hex_to_int(dir_1)
			dir_1 = define_inverse_column_hybrid(dir_1)
		dir_new_number = dir_1
	return dir_new_number

def print_(dir_num):
	#测试输出字典
	for key, num in dir_num.items():
		print(num)

def get_outcome(dir_num):
	#输出解密之后的内容
	dir_num = define_column_rotation(dir_num)
	string = ''
	for i in range(4):
		list_num = dir_num[i]
		for j in range(4):
			num = list_num[j]
			num = chr(int(num, 16))
			string += num
	return string		

def get_standard_input(string):
	#得到16个字符的输入
	length = len(string)
	length = 16 - length
	for i in range(length):
		string += '0'
	return string	
		
if __name__ == "__main__":
	print("Enter numbers( 0 - 16 number, if less than 16, it will fill with '0' by default): ")
	clear_number = input()
	clear_number = get_standard_input(clear_number)
	
	#得到明文矩阵
	dir_clear_number = get_matrix_of_clear_number(clear_number)
		
	print_(dir_clear_number) #输出明文矩阵
	print("\n")
	
	#得到密文矩阵
	dir_cipher_number = get_matrix_of_cipher_number()
	
	#得到扩展的密钥
	dir_key_extend = get_extend_key(dir_cipher_number)
	
	print(dir_key_extend) #输出扩展密钥
	print("\n")
	
	dir_new_encrypt_number = define_encryption(dir_clear_number, dir_key_extend)
	print_(dir_new_encrypt_number) #输出密文矩阵
	print("\n")
		
	dir_orinal_ = define_decryption(dir_new_encrypt_number, dir_key_extend)
	print_(dir_orinal_) #输出解密后的矩阵
	
	dir_ = get_outcome(dir_orinal_)
	print(dir_) #输出解密后的原文
	
	

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转载自blog.csdn.net/baidu_38271024/article/details/79626041