normal27 （累加）

pyc文件，网站转py

并进行题目分析

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#!/usr/bin/env python
# visit https://tool.lu/pyc/ for more information
# Version: Python 2.7

import struct
import time

def b(a):
    return a & 0xFFFFFFFFFFFFFFFF #取16位

def c(str):
    return struct.unpack('<Q', bytes(str,encoding='utf8'))[0]
#小端，unsigned longlong

def d(a):
    for i in range(64):
        a = a * 2
        if a > 0xFFFFFFFFFFFFFFFF:
            a = b(a)
            a = b(a ^ 0xB0004B7679FA26B3)#异或奇数
            continue
    return a

if __name__ == '__main__':
    cmp_data = [
        0x6E8DD76D3B876F95,
        0xE206DA09DAF4BED6,
        0x77559D346E134BF1,
        0x61CE39CAC5EAF891,
        0x656C3C155520E36F] #密码长度为40
    input = input('plz input your flag:')#满足长度为8的倍数
    if len(input) % 8 != 0:
        for i in range(8 - len(input) % 8):
            input += '\x00'
        print(input)
    arr = []
    for i in range(int(len(input) / 8)):
        #print(input[i*8:i*8+8],hex(c(input[i * 8:i * 8 + 8])),hex(d(c(input[i * 8:i * 8 + 8]))))  #八位八位切割
        value = d(c(input[i * 8:i * 8 + 8])) #化为unsigned longlong 然后加密
        arr.append(value)
    
    for i in range(5):
        if arr[i] != cmp_data[i]:
            print( 'fail')
            time.sleep(5)
            exit()
            continue
    print('success')
    time.sleep(5)
    exit()

脚本编写

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import struct
data=[0x6E8DD76D3B876F95,
        0xE206DA09DAF4BED6,
        0x77559D346E134BF1,
        0x61CE39CAC5EAF891,
        0x656C3C155520E36F]
flag=''
for i in data :
    for x in range(64):
        if i%2==0:
            i>>=1

        else:
            i^=0xB0004B7679FA26B3
            i+=(2**64)#进位
            i>>=1
    flag+=str(struct.pack('<Q',i),encoding='utf-8')
print(flag)