CTF 密码学

Posted 2020-10-17 木剑配酒

0x00 前言

　　为了练习python，强迫自己能用Python的题都用python解题还有各种密码

0x01 奇怪的字符串

　　实验吧题目：信息保密的需求和实际操作自古有之，与之相应的信息加密与解密也是历史悠久，现有一段经过古典密码理论（不止一种）加密的密文，内容如下：

89 51 82 109 89 50 86 122 97 71 107 61请找出这段密文隐藏的消息明文

　　1.数字都没有超过127,ASCII码，解出来base64，然后再转得到flag

1 import  base64
2 s="89 51 82 109 89 50 86 122 97 71 107 61"
3 s=s.split()
4 d = ""
5 for i in s:
6     d+=(chr(int(i)))
7 print(d)
8 print(base64.b64decode(d))

 0x02 base??

　　实验吧题目：YMFZZTY0D3RMD3RMMTIZ    这一串到底是什么！！！！为什么这么像base32却不是！！！    明文的md5值为16478a151bdd41335dcd69b270f6b985

　　1.给了一段全字母全大写的字符串，提示说像base32，后来试了一下错误的，后面有md5值，网上搜了一下直接解出来了。起始作者的思路

　　2 爆破列出所有的字符串组合的MD5值和给出的md5比较，如果相等，返回原字符串，得出flag，上代码

import base64
import hashlib
import itertools

pwd ="YMFZZTY0D3RMD3RMMTIZ"
tables =[]

#检查md5值是否相同
def check(src):
    m1 =hashlib.md5()
    m1.update(src)
    ans =m1.hexdigest()
    if ans =="16478a151bdd41335dcd69b270f6b985":
        return 1
    else: return 0
#生成字符串的列表
def generateTable(string):
    lists=[]
    for i in range(len(string)):
        if str.isupper(string[i]):
            lists.append([str.lower(string[i]),string[i]])
        else: lists.append([string[i]])
    print(lists)
#generateTable(pwd)
lists=itertools.product([‘y‘, ‘Y‘], [‘m‘, ‘M‘], [‘f‘, ‘F‘], [‘z‘, ‘Z‘], [‘z‘, ‘Z‘], [‘t‘, ‘T‘], [‘y‘, ‘Y‘], [‘0‘],
                  [‘d‘, ‘D‘], [‘3‘], [‘r‘, ‘R‘], [‘m‘, ‘M‘], [‘d‘, ‘D‘], [‘3‘], [‘r‘, ‘R‘], [‘m‘, ‘M‘], [‘m‘, ‘M‘],
                  [‘t‘, ‘T‘], [‘i‘, ‘I‘], [‘z‘, ‘Z‘])
for i in lists:
    temp=‘‘.join(i)
    if check(base64.b64decode(temp)) ==1:
        print(bytes.decode(base64.b64decode(temp)))

 0x03  Morese 加解密

#Author TriompheL
#2017年11月17日
#功能：对于Morse密码的加密解密
DeCODE = {‘.-‘: ‘A‘,     ‘-...‘: ‘B‘,   ‘-.-.‘: ‘C‘,
        ‘-..‘: ‘D‘,    ‘.‘: ‘E‘,      ‘..-.‘: ‘F‘,
        ‘--.‘: ‘G‘,    ‘....‘: ‘H‘,   ‘..‘: ‘I‘,
        ‘.---‘: ‘J‘,   ‘-.-‘: ‘K‘,    ‘.-..‘: ‘L‘,
        ‘--‘: ‘M‘,     ‘-.‘: ‘N‘,     ‘---‘: ‘O‘,
        ‘.--.‘: ‘P‘,   ‘--.-‘: ‘Q‘,   ‘.-.‘: ‘R‘,
        ‘...‘: ‘S‘,    ‘-‘: ‘T‘,      ‘..-‘: ‘U‘,
        ‘...-‘: ‘V‘,   ‘.--‘: ‘W‘,    ‘-..-‘: ‘X‘,
        ‘-.--‘: ‘Y‘,   ‘--..‘: ‘Z‘,

        ‘-----‘: ‘0‘,  ‘.----‘: ‘1‘,  ‘..---‘: ‘2‘,
        ‘...--‘: ‘3‘,  ‘....-‘: ‘4‘,  ‘.....‘: ‘5‘,
        ‘-....‘: ‘6‘,  ‘--...‘: ‘7‘,  ‘---..‘: ‘8‘,
        ‘----.‘: ‘9‘
        }
EnCODE = {‘A‘: ‘.-‘,     ‘B‘: ‘-...‘,   ‘C‘: ‘-.-.‘,
        ‘D‘: ‘-..‘,    ‘E‘: ‘.‘,      ‘F‘: ‘..-.‘,
        ‘G‘: ‘--.‘,    ‘H‘: ‘....‘,   ‘I‘: ‘..‘,
        ‘J‘: ‘.---‘,   ‘K‘: ‘-.-‘,    ‘L‘: ‘.-..‘,
        ‘M‘: ‘--‘,     ‘N‘: ‘-.‘,     ‘O‘: ‘---‘,
        ‘P‘: ‘.--.‘,   ‘Q‘: ‘--.-‘,   ‘R‘: ‘.-.‘,
        ‘S‘: ‘...‘,    ‘T‘: ‘-‘,      ‘U‘: ‘..-‘,
        ‘V‘: ‘...-‘,   ‘W‘: ‘.--‘,    ‘X‘: ‘-..-‘,
        ‘Y‘: ‘-.--‘,   ‘Z‘: ‘--..‘,

        ‘0‘: ‘-----‘,  ‘1‘: ‘.----‘,  ‘2‘: ‘..---‘,
        ‘3‘: ‘...--‘,  ‘4‘: ‘....-‘,  ‘5‘: ‘.....‘,
        ‘6‘: ‘-....‘,  ‘7‘: ‘--...‘,  ‘8‘: ‘---..‘,
        ‘9‘: ‘----.‘
        }
def encrypt():
    msg = raw_input(‘MESSAGE: ‘)
    ans =""
    for char in msg:
        if char == ‘ ‘:
            ans+=‘ ‘
        else:
            ans+=EnCODE[char.upper()]
            ans+=‘ ‘
            #print(EnCODE[char.upper()] + ‘ ‘)
    print(ans)

def decrypt():
    msg =input(‘MESSAGE:‘)
    mores =""
    ans =""
    for char in msg:
        if char==‘.‘ or char==‘-‘:
            mores+=char
        if char ==‘ ‘ and mores !=‘ ‘:
            ans+=DeCODE[mores]
            mores=""
    if mores !="":
        ans+= DeCODE[mores]
        mores=""

    print(ans.lower())

def run():
    para = input(‘1 is encrypt 2 is decrypt : ‘)
    if para == ‘1‘:
        encrypt()
    elif para == ‘2‘:
        decrypt()
    else: print(" your input is error")

run()

0x04 费纳姆密码　　

#encoding:UTF-8

# 费纳姆密码
paswd = "000000000000000000000000000000000"         "000000000000000000101110000110001000000101000000001"


EnCODE ={‘A‘:‘1000001‘ ,‘N‘:‘1001110‘,
        ‘B‘: ‘1000010‘, ‘O‘ :‘1001111‘,
        ‘C‘: ‘1000011‘, ‘P‘ :‘1010000‘,
        ‘D‘: ‘1000100‘, ‘Q‘ :‘1010001‘,
        ‘E‘: ‘1000101‘, ‘R‘ :‘1010010‘,
        ‘F‘: ‘1000110‘, ‘S‘ :‘1010011‘,
        ‘G‘: ‘1000111‘, ‘T‘ :‘1010100‘,
        ‘H‘: ‘1001000‘, ‘U‘ :‘1010101‘,
        ‘I‘: ‘1001001‘, ‘V‘ :‘1010110‘,
        ‘J‘: ‘1001010‘, ‘W‘ :‘1010111‘,
        ‘K‘: ‘1001011‘ ,‘X‘ :‘1011000‘,
        ‘L‘: ‘1001100‘ ,‘Y‘ :‘1011001‘,
        ‘M‘: ‘1001101‘ ,‘Z‘ :‘1011010‘
}
DeCODE={
        ‘1000001‘:‘A‘,  ‘1001110‘:‘N‘,
        ‘1000010‘:‘B‘,  ‘1001111‘:‘O‘,
        ‘1000011‘:‘C‘,  ‘1010000‘:‘P‘,
        ‘1000100‘:‘D‘,  ‘1010001‘:‘Q‘,
        ‘1000101‘:‘E‘,  ‘1010010‘:‘R‘,
        ‘1000110‘:‘F‘,  ‘1010011‘:‘S‘,
        ‘1000111‘:‘G‘,  ‘1010100‘:‘T‘,
        ‘1001000‘:‘H‘,  ‘1010101‘:‘U‘,
        ‘1001001‘:‘I‘,  ‘1010110‘:‘V‘,
        ‘1001010‘:‘J‘,  ‘1010111‘:‘W‘,
        ‘1001011‘:‘K‘,  ‘1011000‘:‘X‘,
        ‘1001100‘:‘L‘,  ‘1011001‘:‘Y‘,
        ‘1001101‘:‘M‘,  ‘1011010‘:‘Z‘
}
#加密
def encrypt():
    msg =input("Input Message:")
    ans  =""

    for char in msg:
        if char ==‘ ‘:
            ans+= ‘ ‘
        else: ans+=EnCODE[char.upper()]+‘ ‘
    print(ans)
#解密
def decrypt():
    msg =input(‘MESSAGE:‘)
    german =""
    ans =""
    for char in msg:
        if char==‘0‘ or char==‘1‘:
            german+=char
        if len(german)==7:
            ans+=DeCODE[german]
            german=""

    print(ans)

def run():
    para = input(‘1 is encrypt 2 is decrypt : ‘)
    if para == ‘1‘:
        encrypt()
    elif para == ‘2‘:
        decrypt()
    else: print(" your input is error")

run()