文章目录

应该算是签到
CyzCC_loves_LOL
Cthulhu Mythos
lovemath

题目附件请自取
链接：https://pan.baidu.com/s/13TwadE6DenseIuRUNZlCKg
提取码：rrpe

应该算是签到

B站搜索直接搜索这个BV号

直接页面Ctrl+F没找出来
搜索引擎找一下有没有通过API查弹幕的方法：https://www.bilibili.com/read/cv7923601

F12点击Network，找到这个视频的cid

从当前时间2021-11-27开始往前找

https://api.bilibili.com/x/v2/dm/web/history/seg.so?type=1&oid=400438565&date=2021-11-27

将历史弹幕文件下载下来，选择UTF-8编码，然后查找关键字即可

D0g3{We1come_to_axbg0g0g0}

CyzCC_loves_LOL

D0g3_LOLteampassword

HAI D0g3 code
I HAS A CODE ITZ "D0g3isthepAssword"
I HAS A MSG ITZ ""
I HAS A COUNTER ITZ 0
I HAS A NUM
IM IN YR LOOP UPPIN YR COUNTER WILE COUNTER SMALLR THAN LEN OF CODE
I HAS A C ITZ CODE!COUNTER
NUM R ORD OF C
NUM R SUM OF NUM AN -3
IZ NUM SMALLR THAN 65?, NUM R SUM OF NUM AN 26, KTHX
NUM R CHR OF NUM
MSG R SMOOSH MSG AN NUM
IM OUTTA YR LOOP
VISIBLE MSG
KTHXBYE

看不懂什么东西，猜测某种编码，搜索引擎找一下

lolcode-language：https://www.dcode.fr/lolcode-language

解码得到ez_misc.zip密码：AGdJfpqebmXpptloa

Program.png根据名称提示一开始以为是npiet，尝试直接编译发现不对

后来经过查阅资料才发现Brainfuck也有一种用像素颜色表示的语言：Brainloller

https://minond.xyz/brainloller/

上传之后点击Play，得到密码：0MTTW CWZVN!

然后根据题目名称提示将密码中的空格换成下划线、以及jinx's_flag_in_silent.jpg的名称，直接尝试SilentEye解密

D0g3{544f3225-bbaf-47dc-ba8d-5bda54cbaecb}

Cthulhu Mythos

hint.mp3听一下，发现前面是泰拉瑞亚的主题曲，后面部分很明显是SSTV

因为格式问题没法直接用QSSTV，RX-SSTV的话又比较麻烦要调整电脑录音设备，就直接用Robot36听吧

网上随便找个地址：https://apkpure.com/cn/robot36-sstv-image-decoder/xdsopl.robot36

下载好传到手机上，安装，然后听就完事了，多听几遍确认信息

>>> from base64 import *
>>> b32decode('MRPVI4TZL5KGK4TSGRZGSYJBPU======')
b'd_Try_Terr4ria!}'

The Evil Watcher.wld

关于泰拉瑞亚地图编辑器

https://www.bilibili.com/read/cv275739?from=search

https://www.binaryconstruct.com/downloads/

https://www.bilibili.com/video/BV1Za4y1a7uN

https://m33.wiki/extension/wld.html

使用TerraMap打开The Evil Watcher.wld；Players->All Spoilers

Sets->Chests找宝箱

在地面上找到四个Class Chest

IQYGOM33

JUYW4ZLD

KI2GM5C

总共四部分，前三部分为：IQYGOM33JUYW4ZLDKI2GM5C
Base32

第四部分可以使用TEdit打开The Evil Watcher.wld

在这个位置找到第四部分

7I4YF6QLO

最终得到的base32为：IQYGOM33JUYW4ZLDKI2GM5C7I4YF6QLO

最终flag

D0g3{M1necR4ft_G0_And_Try_Terr4ria!}

lovemath

hint: not blindwater but you can search it

crc32爆破

-------------Filename CRC Info-------------
[+] flag.zip: 0xc38199da
[+] flag_01.txt: 0xa430239a
[+] flag_02.txt: 0xf81abecd
[+] flag_03.txt: 0x2a75b14e
[+] flag_04.txt: 0x2d2c423c
[+] flag_05.txt: 0xd9e12803
-------------------------------------------

PS D:\Tools\Misc\crc32> python .\crc32.py reverse 0xa430239a
4 bytes: {0x56, 0x34, 0xbc, 0x00}
verification checksum: 0xa430239a (OK)
alternative: 3RAsk0 (OK)
alternative: 5jYl3N (OK)
alternative: ANz4c9 (OK)
alternative: DViXxW (OK)
alternative: EJg5bZ (OK)
alternative: JE94EM (OK)
alternative: JYvhDY (OK)
alternative: O1YuZg (OK)
alternative: R3ix8v (OK)
alternative: _lAJB8 (OK)
alternative: dYZaCR (OK)
alternative: mOBoUw (OK)
alternative: pMrb7f (OK)
alternative: qlmCE3 (OK)
alternative: sq6Mub (OK)
alternative: th1s_I (OK)
alternative: uhpBDP (OK)
PS D:\Tools\Misc\crc32> python .\crc32.py reverse 0xf81abecd
4 bytes: {0xf6, 0x44, 0x6a, 0xcc}
verification checksum: 0xf81abecd (OK)
alternative: 5XyM2J (OK)
alternative: 9kccWY (OK)
alternative: DdIyyS (OK)
alternative: MrQwov (OK)
alternative: ONTi6k (OK)
alternative: RLddTz (OK)
alternative: s_Y0ur (OK)
alternative: uZPcET (OK)
PS D:\Tools\Misc\crc32> python .\crc32.py reverse 0x2a75b14e
4 bytes: {0x39, 0x11, 0xcc, 0x5b}
verification checksum: 0x2a75b14e (OK)
alternative: 0njyYo (OK)
alternative: 4Wf40T (OK)
alternative: 7wmGsD (OK)
alternative: 8x3FTS (OK)
alternative: 9xrwOJ (OK)
alternative: Cn_SKk (OK)
alternative: KdI0GC (OK)
alternative: R_upLi (OK)
alternative: S3GlS4 (OK)
alternative: S_4AWp (OK)
alternative: UFrNfB (OK)
alternative: W7ZmRW (OK)
alternative: _pa33w (OK)
alternative: caljpn (OK)
alternative: d5Fi7M (OK)
alternative: dxkTZE (OK)
alternative: jwtdfK (OK)
alternative: ln2kWy (OK)
alternative: rPFIwl (OK)
alternative: w8iTiR (OK)
alternative: x77UNE (OK)
PS D:\Tools\Misc\crc32> python .\crc32.py reverse 0x2d2c423c
4 bytes: {0x78, 0x6b, 0xc3, 0x45}
verification checksum: 0x2d2c423c (OK)
alternative: 0rd_We (OK)
alternative: 1nj2Mh (OK)
alternative: BSNT74 (OK)
alternative: CrQuEa (OK)
alternative: DkVKoJ (OK)
alternative: FWSU6W (OK)
alternative: P2Suvv (OK)
alternative: Sbdw06 (OK)
alternative: Wfyv1U (OK)
alternative: ZIm5NK (OK)
alternative: dderTO (OK)
alternative: jkzBhA (OK)
alternative: rLHoyf (OK)
alternative: uUOQSM (OK)
PS D:\Tools\Misc\crc32> python .\crc32.py reverse 0xd9e12803
4 bytes: {0x9f, 0x48, 0x0c, 0x36}
verification checksum: 0xd9e12803 (OK)
alternative: 1c0m3e (OK)
alternative: 2_tBqa (OK)
alternative: 3_5sjx (OK)
alternative: 98DoSQ (OK)
alternative: A_Ahce (OK)
alternative: FFFVIN (OK)
alternative: J8qEAU (OK)
alternative: K80tZL (OK)
alternative: NLP5Ef (OK)
alternative: PnkKdg (OK)
alternative: Rs0ET6 (OK)
alternative: WwluNL (OK)
alternative: YxsErB (OK)
alternative: ZD7j0F (OK)
alternative: ZXx61R (OK)
alternative: _a5JCp (OK)
alternative: fIuorK (OK)
alternative: hFj_NE (OK)
alternative: iZd2TH (OK)
alternative: o_madn (OK)
alternative: paXr_b (OK)
alternative: wx_LuI (OK)
PS D:\Tools\Misc\crc32>

得到密码：th1s_Is_Y0ur_pa33w0rd_We1c0m3e

blind.png存在LSB隐写PNG内容

保存下来使用010Editor将前面的几个干扰字节去掉，得到图片

图片OCR：https://www.onlineocr.net/zh_hant/

1251077695482776025338577125579215707216262981842821000162276994967943212822693842845266851984880336702446444408289977864567921038435144120176357529686342977212633764247620567669441602729004003473312468776582473461071462631554533766709934484393185739708817165738912742570170547790145328253304755428563911689057632001795598667127514331122190795355921436735375126688142856470280128821316586008242687241930886868804388482643589009068543771977163419519208340324352

根据题目给出的提示画出自己；需要用到一种叫塔珀自指公式(Tupper's self-referential formula)的公式

https://zh.wikipedia.org/wiki/%E5%A1%94%E7%8F%80%E8%87%AA%E6%8C%87%E5%85%AC%E5%BC%8F

脚本参考：https://www.cnblogs.com/1024th/p/14418846.html

把K的值换成上面的数字即可

"""
Plot Tupper's self-referential formula
"""
import textwrap
import matplotlib.pyplot as pltK = 1251077695482776025338577125579215707216262981842821000162276994967943212822693842845266851984880336702446444408289977864567921038435144120176357529686342977212633764247620567669441602729004003473312468776582473461071462631554533766709934484393185739708817165738912742570170547790145328253304755428563911689057632001795598667127514331122190795355921436735375126688142856470280128821316586008242687241930886868804388482643589009068543771977163419519208340324352H = 17
W = 106if __name__ == "__main__":plt.figure(figsize=(6.8, 4), dpi=600)plt.axis("scaled")K_ = K//17for x in range(W):for y in range(H):if K_ & 1:plt.bar(x+0.5, bottom=y, height=1,width=1, linewidth=0, color="black")K_ >>= 1plt.figtext(0.5, 0.8, r"$\frac{1}{2}<\left\lfloor \operatorname{mod}\left(\left\lfloor\frac{y}{%d}\right\rfloor 2^{-%d\lfloor x\rfloor-\operatorname{mod}(\lfloor y\rfloor, %d)}, 2\right)\right\rfloor$" % (H, H, H), ha="center", va="bottom", fontsize=18)plt.subplots_adjust(top=0.8, bottom=0.5)K_str = textwrap.wrap(str(K), 68)K_str[0] = f"K={K_str[0]}"for i in range(1, len(K_str)):K_str[i] = f"  {K_str[i]}".ljust(70)K_str = "\n".join(K_str)plt.figtext(0.5, 0.45, K_str, fontfamily="monospace", ha="center", va="top")plt.xlim((0, W))plt.ylim((0, H))xticks = list(range(0, W+1))xlabels = ["" for i in xticks]xlabels[0] = "0"xlabels[-1] = str(W)plt.xticks(xticks, xlabels)yticks = list(range(0, H+1))ylabels = ["" for i in yticks]ylabels[0] = "K"ylabels[-1] = f"K+{H}"plt.yticks(yticks, ylabels)plt.grid(b=True, linewidth=0.5)# plt.show()plt.savefig("Tupper-plot.png")# plt.savefig(fname="name", format="svg")

D0g3{I_Lov3_math}

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