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python base64加解密脚本(可变换码表)

2020-2-23 ITHO 二维码 学习笔记

# coding:utf-8

s = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"
#s = "vwxrstuopq34567ABCDEFGHIJyz012PQRSTKLMNOZabcdUVWXYefghijklmn89+/"

def My_base64_encode(inputs):
	# 将字符串转化为2进制
	bin_str = []
	for i in inputs:
		x = str(bin(ord(i))).replace('0b', '')
		bin_str.append('{:0>8}'.format(x))
	#print(bin_str)
	# 输出的字符串
	outputs = ""
	# 不够三倍数,需补齐的次数
	nums = 0
	while bin_str:
		#每次取三个字符的二进制
		temp_list = bin_str[:3]
		if(len(temp_list) != 3):
			nums = 3 - len(temp_list)
			while len(temp_list) < 3:
				temp_list += ['0' * 8]
		temp_str = "".join(temp_list)
		#print(temp_str)
		# 将三个8字节的二进制转换为4个十进制
		temp_str_list = []
		for i in range(0,4):
			temp_str_list.append(int(temp_str[i*6:(i+1)*6],2))
		#print(temp_str_list)
		if nums:
			temp_str_list = temp_str_list[0:4 - nums]
			
		for i in temp_str_list:
			outputs += s[i]
		bin_str = bin_str[3:]
	outputs += nums * '='
	print("Encrypted String:\n%s "%outputs)
	
def My_base64_decode(inputs):
	# 将字符串转化为2进制
	bin_str = []
	for i in inputs:
		if i != '=':
			x = str(bin(s.index(i))).replace('0b', '')
			bin_str.append('{:0>6}'.format(x))
	#print(bin_str)
	# 输出的字符串
	outputs = ""
	nums = inputs.count('=')
	while bin_str:
		temp_list = bin_str[:4]
		temp_str = "".join(temp_list)
		#print(temp_str)
		# 补足8位字节
		if(len(temp_str) % 8 != 0):
			temp_str = temp_str[0:-1 * nums * 2]
		# 将四个6字节的二进制转换为三个字符
		for i in range(0,int(len(temp_str) / 8)):
			outputs += chr(int(temp_str[i*8:(i+1)*8],2))
		bin_str = bin_str[4:]	
	print("Decrypted String:\n%s "%outputs)
	
print()
print("     *************************************")
print("     *    (1)encode         (2)decode    *")	
print("     *************************************")
print()


num = input("Please select the operation you want to perform:\n")
if(num == "1"):
	input_str = input("Please enter a string that needs to be encrypted: \n")
	My_base64_encode(input_str)
else:
	input_str = input("Please enter a string that needs to be decrypted: \n")
	My_base64_decode(input_str)

参考资料:
python编写base64加解密脚本(可变换码表)

标签: python 加密 base64 解密 码表

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