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迎圣诞,拿大奖”活动赛题---DES

程序员文章站 2022-03-12 19:39:33
...

decrypt

import sys

_pythonMajorVersion = sys.version_info[0]

ECB =	0
CBC =	1


PAD_NORMAL = 1
PAD_PKCS5 = 2


class _baseDes(object):
	def __init__(self, mode=ECB, IV=None, pad=None, padmode=PAD_NORMAL):
		if IV:
			IV = self._guardAgainstUnicode(IV)
		if pad:
			pad = self._guardAgainstUnicode(pad)
		self.block_size = 8
		if pad and padmode == PAD_PKCS5:
			raise ValueError("Cannot use a pad character with PAD_PKCS5")
		if IV and len(IV) != self.block_size:
			raise ValueError("Invalid Initial Value (IV), must be a multiple of " + str(self.block_size) + " bytes")


		self._mode = mode
		self._iv = IV
		self._padding = pad
		self._padmode = padmode

	def getKey(self):
		"""getKey() -> bytes"""
		return self.__key

	def setKey(self, key):
		"""Will set the crypting key for this object."""
		key = self._guardAgainstUnicode(key)
		self.__key = key

	def getMode(self):
		"""getMode() -> pyDes.ECB or pyDes.CBC"""
		return self._mode

	def setMode(self, mode):
		"""Sets the type of crypting mode, pyDes.ECB or pyDes.CBC"""
		self._mode = mode

	def getPadding(self):
		"""getPadding() -> bytes of length 1. Padding character."""
		return self._padding

	def setPadding(self, pad):
		"""setPadding() -> bytes of length 1. Padding character."""
		if pad is not None:
			pad = self._guardAgainstUnicode(pad)
		self._padding = pad

	def getPadMode(self):
		"""getPadMode() -> pyDes.PAD_NORMAL or pyDes.PAD_PKCS5"""
		return self._padmode
		
	def setPadMode(self, mode):
		"""Sets the type of padding mode, pyDes.PAD_NORMAL or pyDes.PAD_PKCS5"""
		self._padmode = mode

	def getIV(self):
		"""getIV() -> bytes"""
		return self._iv

	def setIV(self, IV):
		"""Will set the Initial Value, used in conjunction with CBC mode"""
		if not IV or len(IV) != self.block_size:
			raise ValueError("Invalid Initial Value (IV), must be a multiple of " + str(self.block_size) + " bytes")
		IV = self._guardAgainstUnicode(IV)
		self._iv = IV

	def _padData(self, data, pad, padmode):
		if padmode is None:
			padmode = self.getPadMode()
		if pad and padmode == PAD_PKCS5:
			raise ValueError("Cannot use a pad character with PAD_PKCS5")

		if padmode == PAD_NORMAL:
			if len(data) % self.block_size == 0:
				return data

			if not pad:
				pad = self.getPadding()
			if not pad:
				raise ValueError("Data must be a multiple of " + str(self.block_size) + " bytes in length. Use padmode=PAD_PKCS5 or set the pad character.")
			data += (self.block_size - (len(data) % self.block_size)) * pad
		
		elif padmode == PAD_PKCS5:
			pad_len = 8 - (len(data) % self.block_size)
			if _pythonMajorVersion < 3:
				data += pad_len * chr(pad_len)
			else:
				data += bytes([pad_len] * pad_len)

		return data

	def _unpadData(self, data, pad, padmode):
		if not data:
			return data
		if pad and padmode == PAD_PKCS5:
			raise ValueError("Cannot use a pad character with PAD_PKCS5")
		if padmode is None:
			padmode = self.getPadMode()

		if padmode == PAD_NORMAL:
			if not pad:
				pad = self.getPadding()
			if pad:
				data = data[:-self.block_size] + \
				       data[-self.block_size:].rstrip(pad)

		elif padmode == PAD_PKCS5:
			if _pythonMajorVersion < 3:
				pad_len = ord(data[-1])
			else:
				pad_len = data[-1]
			data = data[:-pad_len]

		return data

	def _guardAgainstUnicode(self, data):
		if _pythonMajorVersion < 3:
			if isinstance(data, unicode):
				raise ValueError("pyDes can only work with bytes, not Unicode strings.")
		else:
			if isinstance(data, str):
				try:
					return data.encode('ascii')
				except UnicodeEncodeError:
					pass
				raise ValueError("pyDes can only work with encoded strings, not Unicode.")
		return data

class des(_baseDes):


	# Permutation and translation tables for DES
	__pc1 = [56, 48, 40, 32, 24, 16,  8,
		  0, 57, 49, 41, 33, 25, 17,
		  9,  1, 58, 50, 42, 34, 26,
		 18, 10,  2, 59, 51, 43, 35,
		 62, 54, 46, 38, 30, 22, 14,
		  6, 61, 53, 45, 37, 29, 21,
		 13,  5, 60, 52, 44, 36, 28,
		 20, 12,  4, 27, 19, 11,  3
	]

	# number left rotations of pc1
	__left_rotations = [
		1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1
	]

	# permuted choice key (table 2)
	__pc2 = [
		13, 16, 10, 23,  0,  4,
		 2, 27, 14,  5, 20,  9,
		22, 18, 11,  3, 25,  7,
		15,  6, 26, 19, 12,  1,
		40, 51, 30, 36, 46, 54,
		29, 39, 50, 44, 32, 47,
		43, 48, 38, 55, 33, 52,
		45, 41, 49, 35, 28, 31
	]

	# initial permutation IP
	__ip = [57, 49, 41, 33, 25, 17, 9,  1,
		59, 51, 43, 35, 27, 19, 11, 3,
		61, 53, 45, 37, 29, 21, 13, 5,
		63, 55, 47, 39, 31, 23, 15, 7,
		56, 48, 40, 32, 24, 16, 8,  0,
		58, 50, 42, 34, 26, 18, 10, 2,
		60, 52, 44, 36, 28, 20, 12, 4,
		62, 54, 46, 38, 30, 22, 14, 6
	]

	# Expansion table for turning 32 bit blocks into 48 bits
	__expansion_table = [
		31,  0,  1,  2,  3,  4,
		 3,  4,  5,  6,  7,  8,
		 7,  8,  9, 10, 11, 12,
		11, 12, 13, 14, 15, 16,
		15, 16, 17, 18, 19, 20,
		19, 20, 21, 22, 23, 24,
		23, 24, 25, 26, 27, 28,
		27, 28, 29, 30, 31,  0
	]

	# The (in)famous S-boxes
	__sbox = [
		# S1
		[14, 4, 13, 1, 2, 15, 11, 8, 3, 10, 6, 12, 5, 9, 0, 7,
		 0, 15, 7, 4, 14, 2, 13, 1, 10, 6, 12, 11, 9, 5, 3, 8,
		 4, 1, 14, 8, 13, 6, 2, 11, 15, 12, 9, 7, 3, 10, 5, 0,
		 15, 12, 8, 2, 4, 9, 1, 7, 5, 11, 3, 14, 10, 0, 6, 13],

		# S2
		[15, 1, 8, 14, 6, 11, 3, 4, 9, 7, 2, 13, 12, 0, 5, 10,
		 3, 13, 4, 7, 15, 2, 8, 14, 12, 0, 1, 10, 6, 9, 11, 5,
		 0, 14, 7, 11, 10, 4, 13, 1, 5, 8, 12, 6, 9, 3, 2, 15,
		 13, 8, 10, 1, 3, 15, 4, 2, 11, 6, 7, 12, 0, 5, 14, 9],

		# S3
		[10, 0, 9, 14, 6, 3, 15, 5, 1, 13, 12, 7, 11, 4, 2, 8,
		 13, 7, 0, 9, 3, 4, 6, 10, 2, 8, 5, 14, 12, 11, 15, 1,
		 13, 6, 4, 9, 8, 15, 3, 0, 11, 1, 2, 12, 5, 10, 14, 7,
		 1, 10, 13, 0, 6, 9, 8, 7, 4, 15, 14, 3, 11, 5, 2, 12],

		# S4
		[7, 13, 14, 3, 0, 6, 9, 10, 1, 2, 8, 5, 11, 12, 4, 15,
		 13, 8, 11, 5, 6, 15, 0, 3, 4, 7, 2, 12, 1, 10, 14, 9,
		 10, 6, 9, 0, 12, 11, 7, 13, 15, 1, 3, 14, 5, 2, 8, 4,
		 3, 15, 0, 6, 10, 1, 13, 8, 9, 4, 5, 11, 12, 7, 2, 14],

		# S5
		[2, 12, 4, 1, 7, 10, 11, 6, 8, 5, 3, 15, 13, 0, 14, 9,
		 14, 11, 2, 12, 4, 7, 13, 1, 5, 0, 15, 10, 3, 9, 8, 6,
		 4, 2, 1, 11, 10, 13, 7, 8, 15, 9, 12, 5, 6, 3, 0, 14,
		 11, 8, 12, 7, 1, 14, 2, 13, 6, 15, 0, 9, 10, 4, 5, 3],

		# S6
		[12, 1, 10, 15, 9, 2, 6, 8, 0, 13, 3, 4, 14, 7, 5, 11,
		 10, 15, 4, 2, 7, 12, 9, 5, 6, 1, 13, 14, 0, 11, 3, 8,
		 9, 14, 15, 5, 2, 8, 12, 3, 7, 0, 4, 10, 1, 13, 11, 6,
		 4, 3, 2, 12, 9, 5, 15, 10, 11, 14, 1, 7, 6, 0, 8, 13],

		# S7
		[4, 11, 2, 14, 15, 0, 8, 13, 3, 12, 9, 7, 5, 10, 6, 1,
		 13, 0, 11, 7, 4, 9, 1, 10, 14, 3, 5, 12, 2, 15, 8, 6,
		 1, 4, 11, 13, 12, 3, 7, 14, 10, 15, 6, 8, 0, 5, 9, 2,
		 6, 11, 13, 8, 1, 4, 10, 7, 9, 5, 0, 15, 14, 2, 3, 12],

		# S8
		[13, 2, 8, 4, 6, 15, 11, 1, 10, 9, 3, 14, 5, 0, 12, 7,
		 1, 15, 13, 8, 10, 3, 7, 4, 12, 5, 6, 11, 0, 14, 9, 2,
		 7, 11, 4, 1, 9, 12, 14, 2, 0, 6, 10, 13, 15, 3, 5, 8,
		 2, 1, 14, 7, 4, 10, 8, 13, 15, 12, 9, 0, 3, 5, 6, 11],
	]


	# 32-bit permutation function P used on the output of the S-boxes
	__p = [
		15, 6, 19, 20, 28, 11,
		27, 16, 0, 14, 22, 25,
		4, 17, 30, 9, 1, 7,
		23,13, 31, 26, 2, 8,
		18, 12, 29, 5, 21, 10,
		3, 24
	]

	# final permutation IP^-1
	__fp = [
		39,  7, 47, 15, 55, 23, 63, 31,
		38,  6, 46, 14, 54, 22, 62, 30,
		37,  5, 45, 13, 53, 21, 61, 29,
		36,  4, 44, 12, 52, 20, 60, 28,
		35,  3, 43, 11, 51, 19, 59, 27,
		34,  2, 42, 10, 50, 18, 58, 26,
		33,  1, 41,  9, 49, 17, 57, 25,
		32,  0, 40,  8, 48, 16, 56, 24
	]

	# Type of crypting being done
	ENCRYPT =	0x00
	DECRYPT =	0x00

	# Initialisation
	def __init__(self, key, mode=ECB, IV=None, pad=None, padmode=PAD_NORMAL):
		# Sanity checking of arguments.
		if len(key) != 8:
			raise ValueError("Invalid DES key size. Key must be exactly 8 bytes long.")
		_baseDes.__init__(self, mode, IV, pad, padmode)
		self.key_size = 8

		self.L = []
		self.R = []
		self.Kn = [ [0] * 48 ] * 16	# 16 48-bit keys (K1 - K16)
		self.final = []

		self.setKey(key)

	def setKey(self, key):
		"""Will set the crypting key for this object. Must be 8 bytes."""
		_baseDes.setKey(self, key)
		self.__create_sub_keys()

	def __String_to_BitList(self, data):
		"""Turn the string data, into a list of bits (1, 0)'s"""
		if _pythonMajorVersion < 3:

			data = [ord(c) for c in data]
		l = len(data) * 8
		result = [0] * l
		pos = 0
		for ch in data:
			for i in range(0,8):
				result[(pos<<3)+i]=(ch>>i)&1
			pos+=1

		return result

	def __BitList_to_String(self, data):
		"""Turn the list of bits -> data, into a string"""
		l=len(data)/8
		result = [0]*l
		pos = 0
		c=0
		while pos < l:
			for i in range(0,l):
				result[pos] |= data[(pos<<3)+i]<<i
			pos+=1

		if _pythonMajorVersion < 3:
			return ''.join([ chr(c) for c in result ])
		else:
			return bytes(result)

	def __permutate(self, table, block):
		"""Permutate this block with the specified table"""
		return list(map(lambda x: block[x], table))
	

	def __create_sub_keys(self):
		"""Create the 16 subkeys K[1] to K[16] from the given key"""
		key = self.__permutate(des.__pc1, self.__String_to_BitList(self.getKey()))
		i = 0
		self.L = key[:28]
		self.R = key[28:]
		while i < 16:
			j = 0
		
			while j < des.__left_rotations[i]:
				self.L.append(self.L[0])
				del self.L[0]

				self.R.append(self.R[0])
				del self.R[0]

				j += 1

			self.Kn[i] = self.__permutate(des.__pc2, self.L + self.R)

			i += 1

	
	def __des_crypt(self, block, crypt_type):
		"""Crypt the block of data through DES bit-manipulation"""
		block = self.__permutate(des.__ip, block)
		self.L = block[:32]
		self.R = block[32:]

		
		if crypt_type == des.ENCRYPT:
			iteration = 0
			iteration_adjustment = 1

		i = 0
		while i < 16:
			
			tempR = self.R[:]

			
			self.R = self.__permutate(des.__expansion_table, self.R)

		
			self.R = list(map(lambda x, y: x ^ y, self.R, self.Kn[iteration]))
			B = [self.R[:6], self.R[6:12], self.R[12:18], self.R[18:24], self.R[24:30], self.R[30:36], self.R[36:42], self.R[42:]]
			
			j = 0
			Bn = [0] * 32
			pos = 0
			while j < 8:
			
				m = (B[j][0] << 1) + B[j][5]
				n = (B[j][1] << 3) + (B[j][2] << 2) + (B[j][3] << 1) + B[j][4]

				
				v = des.__sbox[j][(m << 4) + n]

				
				Bn[pos] = (v & 8) >> 3
				Bn[pos + 1] = (v & 4) >> 2
				Bn[pos + 2] = (v & 2) >> 1
				Bn[pos + 3] = v & 1

				pos += 4
				j += 1

		
			self.R = self.__permutate(des.__p, Bn)

		
			self.R = list(map(lambda x, y: x ^ y, self.R, self.L))
	
			self.L = tempR

			i += 1
			iteration += iteration_adjustment
		
		
		self.final = self.__permutate(des.__fp, self.R + self.L)
		return self.final


	
	def crypt(self, data, crypt_type):
		"""Crypt the data in blocks, running it through des_crypt()"""

		
		if not data:
			return ''
		if len(data) % self.block_size != 0:
			if crypt_type == des.DECRYPT: 
				raise ValueError("Invalid data length, data must be a multiple of " + str(self.block_size) + " bytes\n.")
			if not self.getPadding():
				raise ValueError("Invalid data length, data must be a multiple of " + str(self.block_size) + " bytes\n. Try setting the optional padding character")
			else:
				data += (self.block_size - (len(data) % self.block_size)) * self.getPadding()

		if self.getMode() == CBC:
			if self.getIV():
				iv = self.__String_to_BitList(self.getIV())
			else:
				raise ValueError("For CBC mode, you must supply the Initial Value (IV) for ciphering")

	
		i = 0
		dict = {}
		result = []

		while i < len(data):

			block = self.__String_to_BitList(data[i:i+8])

			if self.getMode() == CBC:
				if crypt_type == des.ENCRYPT:
					block = list(map(lambda x, y: x ^ y, block, iv))

				processed_block = self.__des_crypt(block, crypt_type)

			else:
				processed_block = self.__des_crypt(block, crypt_type)


	
			result.append(self.__BitList_to_String(processed_block))
	
			i += 8


		if _pythonMajorVersion < 3:
			return ''.join(result)
		else:
			return bytes.fromhex('').join(result)

	def encrypt(self, data, pad=None, padmode=None):
		data = self._guardAgainstUnicode(data)
		if pad is not None:
			pad = self._guardAgainstUnicode(pad)
		data = self._padData(data, pad, padmode)
		return self.crypt(data, des.ENCRYPT)
deskey="imnotkey"
DES = des(deskey)
DES.Kn =[
	[1, 0, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1, 0, 0, 0, 1, 1, 0, 0, 1, 1, 1, 1, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 0, 1, 1, 1, 0, 0, 1, 0, 1, 1, 1], 
	[1, 1, 0, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 1, 1, 0, 1, 0, 1, 0, 0, 1, 1, 1, 1, 0, 1, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1], 
	[0, 0, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 0, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1], 
	[1, 1, 0, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 0, 0, 0, 0, 1, 0, 1, 0, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 0, 0, 0, 0, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1], 
	[1, 1, 1, 0, 0, 0, 1, 1, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 0, 0, 1, 0, 1, 1, 1, 0, 0, 1, 0, 1, 1], 
	[0, 0, 0, 0, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 0, 0, 0, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 0, 1], 
	[0, 1, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 0, 1, 1, 1, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0], 
	[1, 1, 1, 0, 1, 1, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 1, 1, 1, 0, 0, 1, 0, 1, 0, 1, 0], 
	[1, 0, 0, 1, 1, 1, 0, 1, 1, 0, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 0, 1, 1, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 0, 0, 0], 
	[1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 0], 
	[1, 1, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 0, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 0, 1, 1, 1, 0, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 0, 0], 
	[1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 0, 0, 1, 1, 1, 0, 1, 1, 0, 0, 1, 0, 1, 0, 1, 1, 1, 1, 0, 1, 0, 0, 1, 1, 1, 0, 1], 
	[0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, 1, 1, 1, 0, 1], 
	[1, 0, 1, 0, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 0, 1, 0, 0, 1, 0, 1], 
	[0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 1, 0, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 1, 1, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 1, 0, 1, 0, 1], 
	[0, 0, 1, 0, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 0, 0, 1, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 0, 0, 0, 0, 1, 1, 0, 1, 0, 1, 1, 1]
]

DES.setMode(ECB)
correct=[
'\x4d',
'\x6a',
'\x20',
'\x9b',
'\xf3',
'\x3e',
'\x6b',
'\x7b',
'\x9e',
'\x80',
'\xc0',
'\x8c',
'\x21',
'\x5d',
'\x8a',
'\xe9',
'\xf7',
'\x9d',
'\x82',
'\xc5',
'\x28',
'\xaf',
'\x63',
'\x1c',
'\xcd',
'\xc1',
'\xf6',
'\xba',
'\xa0',
'\xd3',
'\x70',
'\x8d',
]
#DES.encrypt(code)==correct

from Crypto.Cipher import Blowfish
import base64
key= deskey+code
cipher = Blowfish.new(key, Blowfish.MODE_ECB)
print cipher.decrypt(base64.b64decode("fxd+VFDXF6lksUAwcB1CMco6fnKqrQcO5nxS/hv3FtN7ngETu95BkjDn/ar+KD+RbmTHximw03g="))

这个题目在原DES的整个加密过程中作了一些修改。

decrypt

解密的过程分为两个部分,一个是将deskey给还原出来,一个是将code给求出来。code的求解很简单,只要我们找到对应的pydes脚本并把decrypt相关的东西补上去就可以了。deskey的还原较为繁琐。但掌握原理后也不是很难。

PC1=[56, 48, 40, 32, 24, 16, 8, 0, 57, 49, 41, 33, 25, 17, 9, 1, 58, 50, 42, 34, 26, 18, 10, 2, 59, 51, 43, 35, 62, 54, 46, 38, 30, 22, 14, 6, 61, 53, 45, 37, 29, 21, 13, 5, 60, 52, 44, 36, 28, 20, 12, 4, 27, 19, 11, 3]
PC2=[13, 16, 10, 23, 0, 4, 2, 27, 14, 5, 20, 9, 22, 18, 11, 3, 25, 7, 15, 6, 26, 19, 12, 1, 40, 51, 30, 36, 46, 54, 29, 39, 50, 44, 32, 47, 43, 48, 38, 55, 33, 52, 45, 41, 49, 35, 28, 31]
movnum = [1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1]#对应16轮中每一轮的循环左移位数
import copy
import sys
_pythonMajorVersion = sys.version_info[0]

ECB = 0
CBC = 1

PAD_NORMAL = 1
PAD_PKCS5 = 2


class _baseDes(object):
    def __init__(self, mode=ECB, IV=None, pad=None, padmode=PAD_NORMAL):
        if IV:
            IV = self._guardAgainstUnicode(IV)
        if pad:
            pad = self._guardAgainstUnicode(pad)
        self.block_size = 8
        if pad and padmode == PAD_PKCS5:
            raise ValueError("Cannot use a pad character with PAD_PKCS5")
        if IV and len(IV) != self.block_size:
            raise ValueError("Invalid Initial Value (IV), must be a multiple of " + str(self.block_size) + " bytes")

        self._mode = mode
        self._iv = IV
        self._padding = pad
        self._padmode = padmode

    def getKey(self):
        """getKey() -> bytes"""
        return self.__key

    def setKey(self, key):
        """Will set the crypting key for this object."""
        key = self._guardAgainstUnicode(key)
        self.__key = key

    def getMode(self):
        """getMode() -> pyDes.ECB or pyDes.CBC"""
        return self._mode

    def setMode(self, mode):
        """Sets the type of crypting mode, pyDes.ECB or pyDes.CBC"""
        self._mode = mode

    def getPadding(self):
        """getPadding() -> bytes of length 1. Padding character."""
        return self._padding

    def setPadding(self, pad):
        """setPadding() -> bytes of length 1. Padding character."""
        if pad is not None:
            pad = self._guardAgainstUnicode(pad)
        self._padding = pad

    def getPadMode(self):
        """getPadMode() -> pyDes.PAD_NORMAL or pyDes.PAD_PKCS5"""
        return self._padmode

    def setPadMode(self, mode):
        """Sets the type of padding mode, pyDes.PAD_NORMAL or pyDes.PAD_PKCS5"""
        self._padmode = mode

    def getIV(self):
        """getIV() -> bytes"""
        return self._iv

    def setIV(self, IV):
        """Will set the Initial Value, used in conjunction with CBC mode"""
        if not IV or len(IV) != self.block_size:
            raise ValueError("Invalid Initial Value (IV), must be a multiple of " + str(self.block_size) + " bytes")
        IV = self._guardAgainstUnicode(IV)
        self._iv = IV

    def _padData(self, data, pad, padmode):
        if padmode is None:
            padmode = self.getPadMode()
        if pad and padmode == PAD_PKCS5:
            raise ValueError("Cannot use a pad character with PAD_PKCS5")

        if padmode == PAD_NORMAL:
            if len(data) % self.block_size == 0:
                return data

            if not pad:
                pad = self.getPadding()
            if not pad:
                raise ValueError("Data must be a multiple of " + str(
                    self.block_size) + " bytes in length. Use padmode=PAD_PKCS5 or set the pad character.")
            data += (self.block_size - (len(data) % self.block_size)) * pad

        elif padmode == PAD_PKCS5:
            pad_len = 8 - (len(data) % self.block_size)
            if _pythonMajorVersion < 3:
                data += pad_len * chr(pad_len)
            else:
                data += bytes([pad_len] * pad_len)

        return data

    def _unpadData(self, data, pad, padmode):
        if not data:
            return data
        if pad and padmode == PAD_PKCS5:
            raise ValueError("Cannot use a pad character with PAD_PKCS5")
        if padmode is None:
            padmode = self.getPadMode()

        if padmode == PAD_NORMAL:
            if not pad:
                pad = self.getPadding()
            if pad:
                data = data[:-self.block_size] + \
                       data[-self.block_size:].rstrip(pad)

        elif padmode == PAD_PKCS5:
            if _pythonMajorVersion < 3:
                pad_len = ord(data[-1])
            else:
                pad_len = data[-1]
            data = data[:-pad_len]

        return data

    def _guardAgainstUnicode(self, data):
        if _pythonMajorVersion < 3:
            if isinstance(data, unicode):
                raise ValueError("pyDes can only work with bytes, not Unicode strings.")
        else:
            if isinstance(data, str):
                try:
                    return data.encode('ascii')
                except UnicodeEncodeError:
                    pass
                raise ValueError("pyDes can only work with encoded strings, not Unicode.")
        return data


class des(_baseDes):
    # Permutation and translation tables for DES
    __pc1 = [56, 48, 40, 32, 24, 16, 8,
             0, 57, 49, 41, 33, 25, 17,
             9, 1, 58, 50, 42, 34, 26,
             18, 10, 2, 59, 51, 43, 35,
             62, 54, 46, 38, 30, 22, 14,
             6, 61, 53, 45, 37, 29, 21,
             13, 5, 60, 52, 44, 36, 28,
             20, 12, 4, 27, 19, 11, 3
             ]

    # number left rotations of pc1
    __left_rotations = [
        1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1
    ]

    # permuted choice key (table 2)
    __pc2 = [
        13, 16, 10, 23, 0, 4,
        2, 27, 14, 5, 20, 9,
        22, 18, 11, 3, 25, 7,
        15, 6, 26, 19, 12, 1,
        40, 51, 30, 36, 46, 54,
        29, 39, 50, 44, 32, 47,
        43, 48, 38, 55, 33, 52,
        45, 41, 49, 35, 28, 31
    ]

    # initial permutation IP
    __ip = [57, 49, 41, 33, 25, 17, 9, 1,
            59, 51, 43, 35, 27, 19, 11, 3,
            61, 53, 45, 37, 29, 21, 13, 5,
            63, 55, 47, 39, 31, 23, 15, 7,
            56, 48, 40, 32, 24, 16, 8, 0,
            58, 50, 42, 34, 26, 18, 10, 2,
            60, 52, 44, 36, 28, 20, 12, 4,
            62, 54, 46, 38, 30, 22, 14, 6
            ]

    # Expansion table for turning 32 bit blocks into 48 bits
    __expansion_table = [
        31, 0, 1, 2, 3, 4,
        3, 4, 5, 6, 7, 8,
        7, 8, 9, 10, 11, 12,
        11, 12, 13, 14, 15, 16,
        15, 16, 17, 18, 19, 20,
        19, 20, 21, 22, 23, 24,
        23, 24, 25, 26, 27, 28,
        27, 28, 29, 30, 31, 0
    ]

    # The (in)famous S-boxes
    __sbox = [
        # S1
        [14, 4, 13, 1, 2, 15, 11, 8, 3, 10, 6, 12, 5, 9, 0, 7,
         0, 15, 7, 4, 14, 2, 13, 1, 10, 6, 12, 11, 9, 5, 3, 8,
         4, 1, 14, 8, 13, 6, 2, 11, 15, 12, 9, 7, 3, 10, 5, 0,
         15, 12, 8, 2, 4, 9, 1, 7, 5, 11, 3, 14, 10, 0, 6, 13],

        # S2
        [15, 1, 8, 14, 6, 11, 3, 4, 9, 7, 2, 13, 12, 0, 5, 10,
         3, 13, 4, 7, 15, 2, 8, 14, 12, 0, 1, 10, 6, 9, 11, 5,
         0, 14, 7, 11, 10, 4, 13, 1, 5, 8, 12, 6, 9, 3, 2, 15,
         13, 8, 10, 1, 3, 15, 4, 2, 11, 6, 7, 12, 0, 5, 14, 9],

        # S3
        [10, 0, 9, 14, 6, 3, 15, 5, 1, 13, 12, 7, 11, 4, 2, 8,
         13, 7, 0, 9, 3, 4, 6, 10, 2, 8, 5, 14, 12, 11, 15, 1,
         13, 6, 4, 9, 8, 15, 3, 0, 11, 1, 2, 12, 5, 10, 14, 7,
         1, 10, 13, 0, 6, 9, 8, 7, 4, 15, 14, 3, 11, 5, 2, 12],

        # S4
        [7, 13, 14, 3, 0, 6, 9, 10, 1, 2, 8, 5, 11, 12, 4, 15,
         13, 8, 11, 5, 6, 15, 0, 3, 4, 7, 2, 12, 1, 10, 14, 9,
         10, 6, 9, 0, 12, 11, 7, 13, 15, 1, 3, 14, 5, 2, 8, 4,
         3, 15, 0, 6, 10, 1, 13, 8, 9, 4, 5, 11, 12, 7, 2, 14],

        # S5
        [2, 12, 4, 1, 7, 10, 11, 6, 8, 5, 3, 15, 13, 0, 14, 9,
         14, 11, 2, 12, 4, 7, 13, 1, 5, 0, 15, 10, 3, 9, 8, 6,
         4, 2, 1, 11, 10, 13, 7, 8, 15, 9, 12, 5, 6, 3, 0, 14,
         11, 8, 12, 7, 1, 14, 2, 13, 6, 15, 0, 9, 10, 4, 5, 3],

        # S6
        [12, 1, 10, 15, 9, 2, 6, 8, 0, 13, 3, 4, 14, 7, 5, 11,
         10, 15, 4, 2, 7, 12, 9, 5, 6, 1, 13, 14, 0, 11, 3, 8,
         9, 14, 15, 5, 2, 8, 12, 3, 7, 0, 4, 10, 1, 13, 11, 6,
         4, 3, 2, 12, 9, 5, 15, 10, 11, 14, 1, 7, 6, 0, 8, 13],

        # S7
        [4, 11, 2, 14, 15, 0, 8, 13, 3, 12, 9, 7, 5, 10, 6, 1,
         13, 0, 11, 7, 4, 9, 1, 10, 14, 3, 5, 12, 2, 15, 8, 6,
         1, 4, 11, 13, 12, 3, 7, 14, 10, 15, 6, 8, 0, 5, 9, 2,
         6, 11, 13, 8, 1, 4, 10, 7, 9, 5, 0, 15, 14, 2, 3, 12],

        # S8
        [13, 2, 8, 4, 6, 15, 11, 1, 10, 9, 3, 14, 5, 0, 12, 7,
         1, 15, 13, 8, 10, 3, 7, 4, 12, 5, 6, 11, 0, 14, 9, 2,
         7, 11, 4, 1, 9, 12, 14, 2, 0, 6, 10, 13, 15, 3, 5, 8,
         2, 1, 14, 7, 4, 10, 8, 13, 15, 12, 9, 0, 3, 5, 6, 11],
    ]

    # 32-bit permutation function P used on the output of the S-boxes
    __p = [
        15, 6, 19, 20, 28, 11,
        27, 16, 0, 14, 22, 25,
        4, 17, 30, 9, 1, 7,
        23, 13, 31, 26, 2, 8,
        18, 12, 29, 5, 21, 10,
        3, 24
    ]

    # final permutation IP^-1
    __fp = [
        39, 7, 47, 15, 55, 23, 63, 31,
        38, 6, 46, 14, 54, 22, 62, 30,
        37, 5, 45, 13, 53, 21, 61, 29,
        36, 4, 44, 12, 52, 20, 60, 28,
        35, 3, 43, 11, 51, 19, 59, 27,
        34, 2, 42, 10, 50, 18, 58, 26,
        33, 1, 41, 9, 49, 17, 57, 25,
        32, 0, 40, 8, 48, 16, 56, 24
    ]

    # Type of crypting being done
    ENCRYPT = 0x00
    DECRYPT = 0x01

    # Initialisation
    def __init__(self, key, mode=ECB, IV=None, pad=None, padmode=PAD_NORMAL):
        # Sanity checking of arguments.
        if len(key) != 8:
            raise ValueError("Invalid DES key size. Key must be exactly 8 bytes long.")
        _baseDes.__init__(self, mode, IV, pad, padmode)
        self.key_size = 8

        self.L = []
        self.R = []
        self.Kn = [[0] * 48] * 16  # 16 48-bit keys (K1 - K16)
        self.final = []

        self.setKey(key)

    def setKey(self, key):
        """Will set the crypting key for this object. Must be 8 bytes."""
        _baseDes.setKey(self, key)
        self.__create_sub_keys()

    def __String_to_BitList(self, data):
        """Turn the string data, into a list of bits (1, 0)'s"""
        if _pythonMajorVersion < 3:
            data = [ord(c) for c in data]
        l = len(data) * 8
        result = [0] * l
        pos = 0
        for ch in data:
            for i in range(0, 8):
                result[(pos << 3) + i] = (ch >> i) & 1
            pos += 1

        return result

    def __BitList_to_String(self, data):
        """Turn the list of bits -> data, into a string"""
        l = len(data) // 8
        result = [0] * l
        pos = 0
        c = 0
        while pos < l:
            for i in range(0, l):
                result[pos] |= data[(pos << 3) + i] << i
            pos += 1

        if _pythonMajorVersion < 3:
            return ''.join([chr(c) for c in result])
        else:
            return bytes(result)
    def BitList_to_String(self, data):#这里我自己改动了一下,目的是还原**,这里去掉了私有方法
        """Turn the list of bits -> data, into a string"""
        l = len(data) // 8
        result = [0] * l
        pos = 0
        c = 0
        while pos < l:
            for i in range(0, l):
                result[pos] |= eval(data[(pos << 3) + i]) << i#这里多了一个eval
            pos += 1

        if _pythonMajorVersion < 3:
            return ''.join([chr(c) for c in result])
        else:
            return bytes(result)

    def __permutate(self, table, block):
        """Permutate this block with the specified table"""
        return list(map(lambda x: block[x], table))

    def __create_sub_keys(self):
        """Create the 16 subkeys K[1] to K[16] from the given key"""
        key = self.__permutate(des.__pc1, self.__String_to_BitList(self.getKey()))
        i = 0
        self.L = key[:28]
        self.R = key[28:]
        while i < 16:
            j = 0

            while j < des.__left_rotations[i]:
                self.L.append(self.L[0])
                del self.L[0]

                self.R.append(self.R[0])
                del self.R[0]

                j += 1

            self.Kn[i] = self.__permutate(des.__pc2, self.L + self.R)

            i += 1

    def __des_crypt(self, block, crypt_type):
        """Crypt the block of data through DES bit-manipulation"""
        block = self.__permutate(des.__ip, block)
        self.L = block[:32]
        self.R = block[32:]

        if crypt_type == des.ENCRYPT:
            iteration = 0
            iteration_adjustment = 1
        else:
            iteration = 15
            iteration_adjustment = -1

        i = 0
        while i < 16:

            tempR = self.R[:]

            self.R = self.__permutate(des.__expansion_table, self.R)

            self.R = list(map(lambda x, y: x ^ y, self.R, self.Kn[iteration]))
            B = [self.R[:6], self.R[6:12], self.R[12:18], self.R[18:24], self.R[24:30], self.R[30:36], self.R[36:42],
                 self.R[42:]]

            j = 0
            Bn = [0] * 32
            pos = 0
            while j < 8:
                m = (B[j][0] << 1) + B[j][5]
                n = (B[j][1] << 3) + (B[j][2] << 2) + (B[j][3] << 1) + B[j][4]

                v = des.__sbox[j][(m << 4) + n]

                Bn[pos] = (v & 8) >> 3
                Bn[pos + 1] = (v & 4) >> 2
                Bn[pos + 2] = (v & 2) >> 1
                Bn[pos + 3] = v & 1

                pos += 4
                j += 1

            self.R = self.__permutate(des.__p, Bn)

            self.R = list(map(lambda x, y: x ^ y, self.R, self.L))

            self.L = tempR

            i += 1
            iteration += iteration_adjustment

        self.final = self.__permutate(des.__fp, self.R + self.L)
        return self.final

    def crypt(self, data, crypt_type):
        """Crypt the data in blocks, running it through des_crypt()"""

        if not data:
            return ''
        if len(data) % self.block_size != 0:
            if crypt_type == des.DECRYPT:
                raise ValueError(
                    "Invalid data length, data must be a multiple of " + str(self.block_size) + " bytes\n.")
            if not self.getPadding():
                raise ValueError("Invalid data length, data must be a multiple of " + str(
                    self.block_size) + " bytes\n. Try setting the optional padding character")
            else:
                data += (self.block_size - (len(data) % self.block_size)) * self.getPadding()

        if self.getMode() == CBC:
            if self.getIV():
                iv = self.__String_to_BitList(self.getIV())
            else:
                raise ValueError("For CBC mode, you must supply the Initial Value (IV) for ciphering")

        i = 0
        dict = {}
        result = []

        while i < len(data):

            block = self.__String_to_BitList(data[i:i + 8])

            if self.getMode() == CBC:
                if crypt_type == des.ENCRYPT:
                    block = list(map(lambda x, y: x ^ y, block, iv))

                processed_block = self.__des_crypt(block, crypt_type)

            else:
                processed_block = self.__des_crypt(block, crypt_type)

            result.append(self.__BitList_to_String(processed_block))

            i += 8

        if _pythonMajorVersion < 3:
            return ''.join(result)
        else:
            return bytes.fromhex('').join(result)

    def encrypt(self, data, pad=None, padmode=None):
        data = self._guardAgainstUnicode(data)
        if pad is not None:
            pad = self._guardAgainstUnicode(pad)
        data = self._padData(data, pad, padmode)
        return self.crypt(data, des.ENCRYPT)

    def decrypt(self, data, pad=None, padmode=None):
        """decrypt(data, [pad], [padmode]) -> bytes

        data : Bytes to be encrypted
        pad  : Optional argument for decryption padding. Must only be one byte
        padmode : Optional argument for overriding the padding mode.

        The data must be a multiple of 8 bytes and will be decrypted
        with the already specified key. In PAD_NORMAL mode, if the
        optional padding character is supplied, then the un-encrypted
        data will have the padding characters removed from the end of
        the bytes. This pad removal only occurs on the last 8 bytes of
        the data (last data block). In PAD_PKCS5 mode, the special
        padding end markers will be removed from the data after decrypting.
        """
        data = self._guardAgainstUnicode(data)
        if pad is not None:
            pad = self._guardAgainstUnicode(pad)
        data = self.crypt(data, des.DECRYPT)
        return self._unpadData(data, pad, padmode)


correct = [
    '\x4d',
    '\x6a',
    '\x20',
    '\x9b',
    '\xf3',
    '\x3e',
    '\x6b',
    '\x7b',
    '\x9e',
    '\x80',
    '\xc0',
    '\x8c',
    '\x21',
    '\x5d',
    '\x8a',
    '\xe9',
    '\xf7',
    '\x9d',
    '\x82',
    '\xc5',
    '\x28',
    '\xaf',
    '\x63',
    '\x1c',
    '\xcd',
    '\xc1',
    '\xf6',
    '\xba',
    '\xa0',
    '\xd3',
    '\x70',
    '\x8d',
]
deskey = "imnotkey"
DES = des(deskey)
DES.Kn = [
    [1, 0, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1, 0, 0, 0, 1, 1, 0, 0, 1, 1, 1, 1, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 0,
     1, 1, 1, 0, 0, 1, 0, 1, 1, 1],
    [1, 1, 0, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 1, 1, 0, 1, 0, 1, 0, 0, 1, 1, 1, 1, 0, 1, 0, 0, 0,
     1, 1, 1, 1, 0, 0, 0, 1, 1, 1],
    [0, 0, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 0, 1,
     1, 1, 1, 1, 0, 0, 0, 1, 1, 1],
    [1, 1, 0, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 0, 0, 0, 0, 1, 0, 1, 0, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 0, 0, 0, 0, 1,
     1, 1, 1, 1, 0, 0, 0, 1, 1, 1],
    [1, 1, 1, 0, 0, 0, 1, 1, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 0, 0, 1,
     0, 1, 1, 1, 0, 0, 1, 0, 1, 1],
    [0, 0, 0, 0, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 0, 0, 0, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1,
     0, 1, 0, 1, 0, 0, 1, 0, 0, 1],
    [0, 1, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 0, 1, 1, 1, 1, 0, 1,
     0, 1, 0, 1, 1, 0, 1, 0, 1, 0],
    [1, 1, 1, 0, 1, 1, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 1,
     1, 1, 0, 0, 1, 0, 1, 0, 1, 0],
    [1, 0, 0, 1, 1, 1, 0, 1, 1, 0, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 0, 1, 1, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1,
     0, 1, 0, 1, 1, 1, 1, 0, 0, 0],
    [1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 1, 1, 0, 1, 1, 1,
     0, 1, 0, 1, 1, 1, 0, 1, 0, 0],
    [1, 1, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 0, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 0, 1, 1, 1, 0, 0, 1, 1,
     1, 0, 1, 0, 1, 1, 1, 1, 0, 0],
    [1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 0, 0, 1, 1, 1, 0, 1, 1, 0, 0, 1, 0, 1, 0, 1, 1, 1,
     1, 0, 1, 0, 0, 1, 1, 1, 0, 1],
    [0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 0,
     1, 0, 1, 0, 1, 1, 1, 1, 0, 1],
    [1, 0, 1, 0, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 0, 1, 1, 1, 1, 0,
     1, 1, 1, 0, 1, 0, 0, 1, 0, 1],
    [0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 1, 0, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 1, 1, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0,
     1, 1, 1, 0, 1, 1, 0, 1, 0, 1],
    [0, 0, 1, 0, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 0, 0, 1, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 0, 0,
     0, 0, 1, 1, 0, 1, 0, 1, 1, 1]
]
#以下为子**还原原**的过程。
key1=[1, 0, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1, 0, 0, 0, 1, 1, 0, 0, 1, 1, 1, 1, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 0,1, 1, 1, 0, 0, 1, 0, 1, 1, 1]
key2=[1, 1, 0, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 1, 1, 0, 1, 0, 1, 0, 0, 1, 1, 1, 1, 0, 1, 0, 0, 0,1, 1, 1, 1, 0, 0, 0, 1, 1, 1]
dic={}#用来存储pc2逆置换后的8个未知数的值。
def gen_key(C1,D1):
    tempc=C1[1:]+C1[:1]
    tempd=D1[1:]+D1[:1]
    tempCD1=tempc+tempd
    tempkey=[]
    for i in range(len(PC2)):
        tempkey.append(tempCD1[PC2[i]])
    return tempkey#轮运算得到下一***
def RE_pc2():
    CD1=['*']*56
    for i in range(len(PC2)):
        CD1[PC2[i]]=str(key1[i])#初步还原CD1
    a=97
    #print(CD1)
    for i in range(len(CD1)):
        if CD1[i]=='*':
            CD1[i]=chr(a)
            a+=1
    C1=CD1[:28]
    D1=CD1[28:]
    en_key2=gen_key(C1,D1)
    for i in range(len(en_key2)):
        if en_key2[i]!=str(key2[i]):
            dic[en_key2[i]]=str(key2[i])
    for i in range(97,105):
        CD1[CD1.index(chr(i))]=dic[chr(i)]#还原完成CD1,PC2逆置换完成。
    #print(CD1)
    return CD1
def RE_pc1(CD1):
    tempc=CD1[:28]
    tempd=CD1[28:]
    C1=tempc[-1:]+tempc[:-1]
    D1=tempd[-1:]+tempd[:-1]
    #循环左移的逆过程完成。
    new_CD1=C1+D1
    pre_key=['*']*64
    for i in range(len(PC1)):
        pre_key[PC1[i]]=new_CD1[i]
    #逆pc1完成。
    return pre_key
def crackit(pre_key):
    '''**8个校验位'''
    keys=[]
    for i in range(256):
        s=bin(i)[2:].zfill(8)
        temp=0
        for j in range(len(pre_key)):
            if (j+1)%8==0:
                pre_key[j]=s[temp]
                temp+=1
        c=copy.deepcopy(pre_key)
        keys.append(c)
        for j in range(len(pre_key)):
            if (j+1)%8==0:
                pre_key[j]='*'
    return keys
CD1=RE_pc2()
pre_key=RE_pc1(CD1)
#print(pre_key)
keys=crackit(pre_key)
import Crypto.Util.number
from Crypto.Cipher import Blowfish
import base64
'''
    def __String_to_BitList(self, data):
        """Turn the string data, into a list of bits (1, 0)'s"""
        if _pythonMajorVersion < 3:
            data = [ord(c) for c in data]
        l = len(data) * 8
        result = [0] * l
        pos = 0
        for ch in data:
            for i in range(0, 8):
                result[(pos << 3) + i] = (ch >> i) & 1
            pos += 1

        return result
#通过这个原**的数字转换过程,可以知道,返回的result其实每个字节都reverse了,所以在还原原**时,也需要对每一个字节进行reverse,但是在原转换过程中似乎是一一对应的。
'''
# for i in range(len(keys)):
#     print(DES.BitList_to_String(keys[i]))#这里调用的这个方法原来是私有方法,不能被实例调用,所以这里改了一下,新增了一个可以实例化的方法。
#通过输出可以得到,符合条件的就是第一个
#
deskey=b'CodinGay'
c=b'Mj \x9b\xf3>k{\x9e\x80\xc0\x8c!]\x8a\xe9\xf7\x9d\x82\xc5(\xafc\x1c\xcd\xc1\xf6\xba\xa0\xd3p\x8d'
code=DES.decrypt(c)
key=deskey+code
cipher = Blowfish.new(key, Blowfish.MODE_ECB)
print(cipher.decrypt(base64.b64decode("fxd+VFDXF6lksUAwcB1CMco6fnKqrQcO5nxS/hv3FtN7ngETu95BkjDn/ar+KD+RbmTHximw03g=")))












#b'flag{R1p0s4Riposa_1n_p4c3_Nel1_illusi0n3_che_ha1_cr34t0}'
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