Crypto-Pirat, Internetwache CTF crypto50 challenge. Writeup: http://losfuzzys.github.io/writeup/2016/02/21/iwctf2016-crypto-pirat/

README.txt

♆♀♇♀♆ ♇♇♀♆⊕ ♇♀♇♀♆ ♇♆♇♆⊕ ♆♇♆♇♇ ♀♆♇♆⊕ ♆♇♆♇♆ ♇♆♇♆⊕ ♆♇♇♀♇ ♀♆⊕♇♀ ♆⊕♇♀♆ ⊕♆♇♆♇ ♇♀♆♇♆ ⊕♇♀♇♀ ♆⊕♆♇♆ ♇♆♇♇♀ ♆⊕♆♇♆ ♇♆♇♆⊕ ♆♇♆♇♆ ♇♆⊕♇♀ ♆♇♇♀♆ ♇♆⊕♇♀ ♆♇♆♇♇ ♀♆⊕♆♇ ♆♇♇♀♇ ♀♇♀♆⊕ ♆♇♆♇♇ ♀♆⊕♇♀ ♇♀♆♇♆ ⊕♆♇♇♀ ♆⊕♇♀♆ ♇♇♀♇♀ ♆⊕♆♇♆ ♇♆♇♆♇ ♆⊕♇♀♆ ♇♇♀♆♇ ♆⊕♇♀♆ ♇♆♇♇♀ ♆⊕♆♇♆ ♇♇♀♇♀ ♇♀♆⊕♇ ♀♆♇♆♇ ♆⊕♇♀♇ ♀♇♀♆⊕ ♇♀♇♀♆ ♇♆♇♆⊕ ♆♇♆♇♆ ♇♆⊕♆♇ ♇♀♇♀♆ ⊕♆♇♆♇ ♆♇♆♇♇ ♀♆⊕♇♀ ♇♀♆♇♆ ♇♆⊕♆♇ ♆♇♆♇♇ ♀♇♀♆⊕ ♆♇♆♇♆ ♇♆⊕♆♇ ♇♀♆♇♆ ♇♆⊕♆♇ ♆♇♆♇♆ ♇♆♇♆⊕ ♆♇♇♀♇ ♀♆⊕♇♀ ♇♀♆♇♆ ⊕♆♇♆⊕ ♆♇♆♇♇ ♀♇♀♇♀ ♆⊕♇♀♆ ♇♇♀♆♇ ♆⊕♇♀♇ ♀♆♇♆♇ ♆♇♆⊕♇ ♀♆♇♆⊕ ♇♀♇♀♆ ♇♆♇♆⊕ ♆♇♆♇♆ ♇♆⊕♇♀ ♆♇♆♇♇ ♀♆⊕♆♇ ♆⊕♇♀♇ ♀♇♀♆⊕ ♆♇♇♀♆ ♇♆⊕♆♇ ♇♀♇♀♇ ♀♆⊕♆♇ ♇♀♇♀♆ ♇♆⊕♆♇ ♆♇♇♀♆ ⊕♇♀♆♇ ♆♇♆♇♇ ♀♆⊕♇♀ ♆♇♆♇♆ ♇♇♀♆⊕ ♇♀♆♇♆ ♇♆♇♇♀ ♆⊕♇♀♆ ♇♆♇♆♇ ♇♀♆⊕♇ ♀♆♇♆♇ ♆♇♇♀♆ ⊕♇♀♆♇ ♆♇♆♇♇ ♀

attack.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-

from pwn import *
import morse_talk as morse
from base64 import b32decode

log.info('load the ciphertext ... ')
ciphertext = open('README.txt').read()

log.info('initialize planets and mapping ... ')
neptun = '♆'  # 8
pluto = '♇'  # 9
venus = '♀'  # 2
earth = '⊕'  # 3
mapping = {'♆': 8, '♇': 9, '♀': 2, '⊕': 3}

log.info('load the tapir table ... ')
tapir = dict()
for line in open('TAPIR.txt').read().split('\n'):
    data = line.split(' ')
    if len(data) <= 1:
        break
    tapir[data[0]] = data[1]

# control chars are not relevant, to we ignore them ... ')
blacklist = ['Zi', 'ZwR']

log.info('decode the planet mapping ...')
i = 0
group = ''
while i < len(ciphertext):
    if ciphertext[i] is not ' ':
        num = mapping[ciphertext[i:i + 3]]
        # print(num),
        i += 3
        group += str(num)
    else:
        # print '_',
        i += 1
clist = list(group)

log.info('planet-decoded plaintext:')
print group

log.info('decode the tapir mapping ...')
tapirDecoded = ''
while len(clist) > 0:
    c = clist.pop(0)
    if len(clist) <= 0:
        break
    if int(float(c)) >= 5:
        c2 = clist.pop(0)
        char = tapir[c + c2]
    else:
        char = tapir[c]
    if char not in blacklist:  # Control chars are not relevant
        tapirDecoded += char
    if char == 'ZwR':  # 'Zwr' is 'Zwischenraum', needed in morse
        tapirDecoded += ' '


log.info('tapir-decoded plaintext:')
print tapirDecoded

log.info('morse-decoded plaintext:')
morsecode = tapirDecoded.replace(' -...-', '')
morseDecoded = morse.decode(morsecode)
print morseDecoded

log.info('base32-decoded plaintext:')
b32decoded = b32decode(morseDecoded + '======')
print b32decoded

for caesarKey in range(1, 27):
    caesarDecrypted = ''
    for c in b32decoded:
        if not c.isalnum():
            caesarDecrypted += c
        else:
            offset = ord('a') if c.islower() else ord('A')
            c = ord(c) - offset
            c = (c + caesarKey) % 26
            caesarDecrypted += chr(c + offset)
    if caesarDecrypted.startswith('IW{'):
        break

log.info('caesar-decrypted plaintext:')
print caesarDecrypted

requirements.txt

pwn==1.0
pwntools==2.2.0
morse-talk==0.2

TAPIR.txt

0 A
1 E
2 I
3 N
4 R
50 B
B1 BE
52 C
53 CH
54 D
55 DE
56 F
57 G
58 GE
59 H
60 J
61 K
62 L
63 M
64 O
65 _
66 _
67 P
68 Q
69 S
70 T
71 TE
72 U
73 UN
74 V
75 _
76 W
77 X
78 Y
79 Z
80 WR
81 Bu
82 Zi
83 ZwR
84 Code
85 RPT
86 _
87 _
88 _
89 .
90 :
91 ,
92 -
93 /
94 (
95 )
96 +
97 =
98 "
99 _
00 0
11 1
22 2
33 3
44 4
55 5
66 6
77 7
88 8
99 9