BJD Crypto wp

• 签到-y1ng

  base64解密：QkpEe1czbGMwbWVfVDBfQkpEQ1RGfQ==

  flag: BJD{W3lc0me_T0_BJDCTF}

• 老文盲了

  罼雧締眔擴灝淛匶襫黼瀬鎶軄鶛驕鳓哵眔鞹鰝

  读音上的问题，将这些字放到百度翻译中听读音得到答案

  flag: BJD{淛匶襫黼瀬鎶軄鶛驕鳓哵}

• cat_flag

  [外链图片转存失败,源站可能有防盗链机制,建议将图片保存下来直接上传(img-N6njW8XJ-1585143250524)(C:\Users\Qin\Desktop\doc\BJD\misc\cat.gif)]

  一排8个团，怀疑是二进制，根据图片的猫吃的东西，饭团为0，鸡腿为1，转为ascii得到flag

  >>> s = '01000010 01001010 01000100 01111011 01001101 00100001 01100001 00110000 01111110 01111101'
  >>> s = s.split(' ')
  >>> m = ''
  >>> for i in s:
  ...     m += chr(int(i, 2))
  ... 
  >>> m
  'BJD{M!a0~}'
  

• 灵能精通-y1ng

  [外链图片转存失败,源站可能有防盗链机制,建议将图片保存下来直接上传(img-zKICVS8F-1585143250525)(C:\Users\Qin\Desktop\doc\BJD\misc\jpg.jpg)]

  flag: BJD{IMKNIGHTSTEMPLAR}

• 燕言燕语-y1ng

  转字符得到：yanzi ZJQ{xilzv_iqssuhoc_suzjg}

  维吉尼亚解密：flag: BJD{yanzi_jiushige_shabi}

  解密网站：https://www.qqxiuzi.cn/bianma/weijiniyamima.php

• Y1nglish-y1ng

  解密网站：https://quipqiup.com/

  注：需要将flag中的y改成k

  flag: BJD{pyth0n_Brut3_f0rc3_oR_quipquip_AI_Cr4ck}

• rsa0

  import gmpy2
  from Crypto.Util import number
  
  e = 15738223
  a = 22999545225230790442989050305360831212567892239847839691681153757935657632110606134527037860192006333762054561955099284250498075820331979680304151103013042 
  b = 1980535616763974112246612697247223559275610064379845242706813039905799273080479345345368299988834060959259695257570793120003055807072769921793736720435364
  c = 57933450475924174593039238409467199689107049441946105839153303179570547437145611201125948099510594729340953435310604752079537763813476544307505686836833455707520204832942324622479274316380418004744782335740953215786115487419880726622517870793048195686696386269367242397101569315477045172857240060668442925542
  
  p = (a+b)/2
  q = (a-b)/2
  
  d = gmpy2.invert(e, (p-1)*(q-1))
  
  m = pow(c, d, p*q)
  print number.long_to_bytes(m)
  

• rsa1

  暂时没弄懂，以后补上
  官方wp：https://github.com/BjdsecCA/BJDCTF2020_March

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