CRYPTO古典密码学学习

1.键盘密码加密

（1）在键盘上进行查找比划，观察形状①------形状------②------圈起来------
（2）键盘坐标加密，法1.- - -以字母所在列为横坐标，数字行为纵坐标；法2- - - 数字行为横坐标，以字母所在列为纵坐标

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2.Brain Fuck 和 Ook密码

Ook与bf在线解密

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3.替代密码

莫斯密码

常用“/”或“ ” 分割，而有些在线编译器无法识别，其中莫斯码表包含少

• 莫斯python脚本

import Morse

MorseList = {
    ".-": "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 morse(string, sign):
    # 分割，字符串string，分割标识符sign
    lists = string.split(sign)
    for code in lists:
        print(MorseList.get(code), end="")
#get（code）后可加.lower()
if __name__ == "__main__":
    Morse.morse("..-. .-.. .- --.", " ")

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凯撒加密

• 恺撒密码的替换方法是通过排列明文和密文字母表，密文字母表示通过将明文字母表向左或向右移动一个固定数目的位置。
• 加密，解密方法
  
• 凯撒python脚本

'''加密
a=int(input('请输入密钥：'))
s=input('请输入字符串')
print(''.join([chr((ord(i)-97+a)%26+97) for i in s]))
'''
#解密
txt = input('请输入密文').strip()
n = input('是否需要推荐(Y/N)').strip()
for i in range(1,26):
    plain=''
    for j in txt:
        if j.islower():
            plain = plain + chr(97+(ord(j)-i-97)%26)
        elif j.isupper():
            plain = plain + chr(65+(ord(j)-i-65)%26)
        else:
            plain = plain + j
    if n.lower() == 'y':
        key = ('flag','ctf','key')
        for m in key:
            if m in plain:
                print('明文可能是：',plain)
                print()
                break
    elif n.lower() == 'n':
        print(plain,end='')
        print()

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$rot13$

• rot13其实为特殊的凯撒加密，其凯撒密钥为13，也称回旋加密，密文与原文交替13

词频分析法 ¹

特点：密文很长

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培根密码

有可能是大写算a或b的一种，小写为另一种
也可能是文字的粗细关系

• 培根密码python脚本

#培根24
a = [
    "AAAAA", "AAAAB", "AAABA", "AAABB", "AABAA", "AABAB",
    "AABBA", "AABBB", "ABAAA", "ABAAB", "ABABA", "ABABB",
    "ABBAA", "ABBAB", "ABBBA", "ABBBB", "BAAAA", "BAAAB",
    "BAABA", "BAABB", "BABAA", "BABAB", "BABBA", "BABBB",
]
b = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', '(ij)', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', '(uv)', 'w', 'x', 'y', 'z']
key = dict(zip(a,b))
txt = input('请输入密文：').replace(' ','').upper()
for i in range(0,len(txt),5):
    print(key.get(txt[i:i+5]),end='')

#培根26
a = [
    "aaaaa", "aaaab", "aaaba", "aaabb", "aabaa", "aabab", "aabba",
    "aabbb", "abaaa", "abaab", "ababa", "ababb", "abbaa", "abbab",
    "abbba", "abbbb", "baaaa", "baaab", "baaba", "baabb",
    "babaa", "babab", "babba", "babbb", "bbaaa", "bbaab",
]
b = 'abcdefghijklmnopqrstuvwxyz'
key = dict(zip(a,b))
txt = input('请输入密文：').replace(' ','').lower()
for i in range(0,len(txt),5):
    print(key.get(txt[i:i+5]),end='')

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仿射加密

解密公式：x = a ^-1(y - b) % 26

• 仿射（affine）解密python脚本(下面这位大佬更全面点)
  https://blog.csdn.net/qq_43531895/article/details/106316161

#求乘法逆元
#y = (ax + b)%26,其中y为密文
#(a*m)%26 = 1,m为乘法逆元

txt = input('请输入密文:')
a = int(input('输入a的值:'))
b = int(input('输入b的值:'))
def get_inverse(a):
	for i in range(1,27):
        if a*i%26==1:
            return i
def decipher(a, b, c):
    a_inv = get_inverse(a)
    p=[]
    for i in c:
        temp=(((ord(i)-97)-b)*a_inv)%26+97
        p.append(chr(temp))
    print(''.join(p))

#暴力破解
for i in txt:
    for j in range(0,26):
        if (a*j+b)%26 == ord(i)-97:#小写97，大写65
            print(chr(j+97),end='')
            

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猪圈密码

猪圈密码在线解密

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base家族

• 16 是 0 - 9 和 A - F
• 32 是大写英文加 1 - 7
• 64 是大小写加 0 - 9 加 / +
  base全家桶进入base家族

#base64
import base64
txt = input('请输入密文：')
key = ''
for i in txt:
    key = key + chr(ord(i)-4)
print(key)

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维吉尼亚加密

• 采用多表替换
• 密钥：比较短的英文字母
  
• 维吉尼亚python脚本

txt = input('请输入密文：')
passward = input('请输入密钥：').lower()
key = [ord(i)-97 for i in passward]
flag = ''
for i in range(len(txt)):
    if txt[i].islower():
        flag += chr(97 + (ord(txt[i]) - 97 - key[i % len(key)]) % 26)
    if txt[i].isupper():
        flag += chr(65 + (ord(txt[i]) - 65 - key[i % len(key)]) % 26)
print(flag)

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费纳姆加密

简称：七位一体转ASCII

• 费纳姆python脚本

txt = input('请输入密文：')
key = input('请输入密钥：')
mi = []
for i in range(0,len(txt),7):
    mi.append(txt[i:i+7])

for m,n in zip(mi,key):
    print(chr(int(m,2) ^ ord(n)),end='')

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杰斐逊加密

• 杰斐逊python脚本

#txt 为密文可以更换
txt = ['ZWAXJGDLUBVIQHKYPNTCRMOSFE',
     'KPBELNACZDTRXMJQOYHGVSFUWI',
     'BDMAIZVRNSJUWFHTEQGYXPLOCK',
     'RPLNDVHGFCUKTEBSXQYIZMJWAO',
     'IHFRLABEUOTSGJVDKCPMNZQWXY',
     'AMKGHIWPNYCJBFZDRUSLOQXVET',
     'GWTHSPYBXIZULVKMRAFDCEONJQ',
     'NOZUTWDCVRJLXKISEFAPMYGHBQ',
     'QWATDSRFHENYVUBMCOIKZGJXPL',
     'WABMCXPLTDSRJQZGOIKFHENYVU',
     'XPLTDAOIKFZGHENYSRUBMCQWVJ',
     'TDSWAYXPLVUBOIKZGJRFHENMCQ',
     'BMCSRFHLTDENQWAOXPYVUIKZGJ',
     'XPHKZGJTDSENYVUBMLAOIRFCQW']
mi = 'HCBTSXWCRQGLES'
key = '2,5,1,3,6,4,9,7,8,14,10,13,11,12'
key = key.split(',')
#print(key)  ['2', '5', '1', '3', '6', '4', '9', '7', '8', '14', '10', '13', '11', '12']
key = [int(i) for i in key]
#print(key)  [2, 5, 1, 3, 6, 4, 9, 7, 8, 14, 10, 13, 11, 12]
flag = []
for m,n in zip(key,mi):#[txt[m-1].index(n):]切片
     flag.append(txt[m-1][txt[m-1].index(n):] + txt[m-1][:txt[m-1].index(n)])
for i in range(26):
     for j in flag:
          print(j[i],end='')
     print()

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4.置换加密

栅栏加密

• 栅栏加密是将明文分成 n 个一组，然后把每个字符第一个字符连接起来，第二个……组成一个新的无规律字符
• 栅栏python脚本

def zhalan(txt,key):
    s = ''
    for m in range(key):
        for n in range(m,len(txt),key):
            s = s + txt[n]
    return s
if __name__ == '__main__':
    txt = input('请输入密文：')
    key = []
    for i in range(2,len(txt)):
        if len(txt)%i == 0:
            key.append(i)
    for j in key:
        flag = zhalan(txt,j)
        print(f'{j}栏:{flag}')

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列置换加密

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波利比奥斯（polybius）加密

又称棋盘加密，将给定的明文加密为两两组合的数字

• 明文：HELLO
• 密文：23 15 31 31 34

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ADFGX加密

可以看作是 polybius 升级版，
其密码用A D F G X 代替了上述5个数字
明文：HELLO
密文：AD DA XX XX DX

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赠CTF密码学离线工具
成功解压之后，点击 $.bat$ 文件即可
CTFcracktools
提取码：qb4f

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1. 需要词频分析离线软件的点击windecryptosetup
   提取码：anto ↩︎