[HNCTF 2022 WEEK2]e@sy_flower

简单花指令

Nop掉

然后整段u c p然后就反汇编

可能反编译的不太对，，看了别人的wp就是ida反编译的有问题

#include<stdio.h>
#include<string.h>
int main()
{int i,j;char ch[]="c~scvdzKCEoDEZ[^roDICUMC";int len=strlen(ch);char v5;for(i=0;i<len;i++) {ch[i]=ch[i]^48;}for(int i=0;i<len/2;i++){v5 = ch[2*i];ch[2*i] = ch[2 * i+1];ch[2*i+1] = v5;} puts(ch);//NSSCTF{Just_junk_Bytess}return 0;
} 

[HNCTF 2022 Week1]X0r

打开

arr处的数据那个2dup，是数据重复两次的意思

#include<stdio.h>
#include<string.h>
int main()
{int i,j;char data[]={0x3FE,0x3EB,0x3EB,0x3FB, 0x3E4, 0x3F6, 0x3D3, 0x3D0, 0x388, 0x3CA, 0x3EF, 0x389, 0x3CB, 0x3EF, 0x3CB, 0x388, 0x3EF,0x3D5, 0x3D9, 0x3CB, 0x3D1, 0x3CD, 0x0A};char ch[28];int len=strlen(data);for(i=0;i<22;i++) {ch[i]=(data[i]-900)^0x34;}puts(ch);
//NSSCTF{x0r_1s_s0_easy}return 0;
} 

[HNCTF 2022 Week1]贝斯是什么乐器啊？

先base64解密，然后在用解密得到的字符 各自+i;

#include<stdio.h>
#include<string.h>
int main()
{int i,j;char ch[]="NRQ@PAu;8j[+(R:2806.i";int len=strlen(ch);for(i=0;i<len;i++) {ch[i]=ch[i]+i;}puts(ch);
//NSSCTF{B@se64_HAHAHA}return 0;
} 

[HNCTF 2022 Week1]你知道什么是Py嘛？

不懂python，转成C语言

#include <stdio.h>
#include <stdlib.h>
#include <string.h>int main() {char s[36];int i;int arr[] = {29, 0, 16, 23, 18, 61, 43, 41, 13, 28, 88, 94, 49, 110, 66, 44, 43, 28, 91, 108, 61, 7, 22, 7, 43, 51, 44, 46, 9, 18, 20, 6, 2, 24};s[0]='N';for(i=1;i<35;i++){s[i]=s[i-1]^arr[i-1];}puts(s);//NSSCTF{Pyth0n_1s_th3_best_l@nguage}return 0;
}

[HNCTF 2022 WEEK2]Packet

脱壳

base64换表

import base64
import stringstr1 = "tLntq1rgE1vqwf8XC19Zmf8Zyxn5Fq=="string1 = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789+/"
string2 = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"print (base64.b64decode(str1.translate(str.maketrans(string1,string2))))#NSSCTF{UPX_1s_s0_3asy}

[HNCTF 2022 Week1]给阿姨倒一杯Jvav

#include <stdio.h>
#include <stdlib.h>
#include <string.h>int main() {int i;char s[] = {180, 136, 137, 147, 191, 137, 147, 191, 148, 136, 133, 191, 134, 140, 129, 135, 191, 65};int n=strlen(s);for(i=0;i<n;i++){s[i]=(s[i]^32)-'@';}puts(s);//This_is_the_flag_!return 0;
}

[HNCTF 2022 Week1]CrackMe

learn learn

od动调--wait me 速速学习

[HNCTF 2022 WEEK2]TTTTTTTTTea

xtea加密，日后研究一下原理和脚本

今天先溜了

#include<stdio.h>int main()
{unsigned int enc[6] = {0xC11EE75A, 0xA4AD0973, 0xF61C9018, 0x32E37BCD, 0x2DCC1F26, 0x344380CC};unsigned int key[4] = {0x10203, 0x4050607, 0x8090A0B, 0x0C0D0E0F};int i, j;long sum = 0, delta = 0x61C88647;// 解码for(i=0;i < 6;i+=2){sum =  0 - (32 * delta);for(j = 0; j < 32; j++) {enc[i+1] -= (((enc[i] >> 5) ^ (16 * enc[i])) + enc[i]) ^ (key[((sum >> 11) & 3)] + sum);sum += delta;enc[i] -= ((((enc[i+1] >> 5) ^ (16 * enc[i+1])) + enc[i+1]) ^ key[sum & 3] + sum);}}// 打印for (i = 0; i < 6; i++){for (j = 0; j<=3; j++){printf("%c", (enc[i] >> (j * 8)) & 0xFF);}}return 0;
}