每天CTF小练（6.6）--基础异或

题目：[HNCTF 2022 Week1]XXXOOORRR

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from flag import flag
from Crypto.Util.number import *
import os

randBytes = [bytes_to_long(os.urandom(64)) for _ in range(3)]
m = bytes_to_long(flag)

print(f'a = {randBytes[0]}')
print(f'b = {randBytes[0] ^ randBytes[1]}')
print(f'c = {randBytes[1] ^ randBytes[2]}')
print(f'd = {m ^ randBytes[0] ^ randBytes[1] ^ randBytes[2]}')

'''
a = 1215421974111272707828609697064234072332368362928440865251897449605952163161176359366553487776268706107760670434157083936287598207881176904763353849369234
b = 10533604054267448009117468094542127075826310122733511023911022436253583775790861879410728001403728088545946257902341417532648419689212361977221573357292618
c = 6401236597601556248960570084212025183497657335932789785351897915858852832577623776212842429736547820800219382515052263929074210010546149322465536545021479
d = 5711309307698496426409561761492698639489294806611133698231840146911562848869711567477706456972659368849642409039245400981517493100724067475248620536111560
'''

代码解释：

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randBytes = [bytes_to_long(os.urandom(64)) for _ in range(3)]



"""
这段代码是用Python来生成一个包含3个随机64字节长的bytes对象的列表。让我逐步解释：

os.urandom(64)：os.urandom()函数是Python中用于生成指定长度的随机字节序列的方法。在这里，os.urandom(64)生成了一个长度为64字节的随机字节序列。

bytes_to_long()：这是一个自定义的函数，它将一个字节序列转换为一个长整型数。在Python中，可以使用int.from_bytes()方法来实现这一转换。

[bytes_to_long(os.urandom(64)) for _ in range(3)]：这是一个列表推导式（list comprehension），它会生成一个包含3个元素的列表。在这里，循环了3次（range(3)），每次生成一个64字节长的随机字节序列，并将其转换为长整型数后加入到列表中。

因此，randBytes列表包含了3个随机的64字节长的长整型数。
"""

代码解释不懂，不用管，直接解。

wp:

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from Crypto.Util.number import *


a = 1215421974111272707828609697064234072332368362928440865251897449605952163161176359366553487776268706107760670434157083936287598207881176904763353849369234
b = 10533604054267448009117468094542127075826310122733511023911022436253583775790861879410728001403728088545946257902341417532648419689212361977221573357292618
c = 6401236597601556248960570084212025183497657335932789785351897915858852832577623776212842429736547820800219382515052263929074210010546149322465536545021479
d = 5711309307698496426409561761492698639489294806611133698231840146911562848869711567477706456972659368849642409039245400981517493100724067475248620536111560

a1=a
b1=b^a
c1=c^b1
m=d^a1^b1^c1
print(m)
print(long_to_bytes(m))

"""
955126884749829153586936045914642979607739079976821931874795098472843959716986845513508261072901299531296605101249003068702245602361385060494717
b'NSSCTF{XOR_ha5_many_propertie5_and_thi5_i5_ju5t_one_of_them}'
"""