Diberikan kittycrypt.tar.gz yang isinya example_input.txt, example_output.txt, flag_output.txt dan main.go
-- example_input.txt
You fools! You will never get my catnip!!!!!!!
-- example output.txt
🐱💻😸😿😼🐱👓😺😾😿🙀🐱💻🐱👓😺😿😹😿🐱💻🐱👓🐱🐱👤😹😿😺🐱👓😹🙀😿😾🐱🏍🐱👓😹😾🐱🚀🐱👤😾🐱💻🐱👓😿😽🐱👓😺😾🐱👤🙀😻🐱👓😸🙀😼🐱👤🐈🐱👓😺🐱👤😼😿😾🐱👓🐈😿😽🙀🐱🚀🐱👓😹😾😹🐱👤🐱👤🐱👓😹🙀🐱🐱👤😾🐱👓🐱🙀😽😿😻🐱👓😹🐱👤🐱🐱👤🐱👤🐱👓🐈😾😽😿🐱💻🐱👓🐈🙀🐱👓😿🐱👤🐱👓😹🐱👤🐱👤😾🐱🏍🐱👓🐈🐱👤🐱😿🐱👤🐱👓😸😾😿🐱👤😾🐱💻🐱🏍😿🙀🐱👓😸😾🙀🙀🐱🐱👓😸🐱👤🐱👓🙀🐱👓🐱👓🐱🙀🙀😾😺🐱👓😺🙀😽😿😸🐱👓😸🐱👤😾🙀🐈🐱👓😺🙀😼🙀😼🐱👓😺😿😿😿😿🐱🏍😿😾🐱👓🐱👓😺😿😽😿🐱🏍🐱👓🐈😾🐈😿😹🐱💻😸🐱👤😹🐱👓😺😿🐱👓🙀🐱🐱👓😺🙀🐱👤😾🐱🏍🐱👓😹🐱👤😸🙀🐱🏍🐱👓😹🐱👤😼🐱👤😾🐱👓🐱🙀🐈🐱👤🐈🐱👓😺😿🐱👤🐱👤😽🐱👓😸🐱👤🐈🐱👤🐱🚀🐱👓😺🐱👤😽🙀😿🐱👓😺😿🐱💻🙀😿🐱👓😺😾🐱👤😿🐱🚀🐱👓😸🙀🐱🏍🐱👤😻🐱👓😸🐱👤🐱💻🐱👤😾🐱👓😹😿😻🙀🐱🚀🐱👓😹😿😿😿😿
-- flag_output.txt
🐱💻😸🙀😼🐱👓😺😾😿🐱👤🐱🐱👓😺😿😹😿🐈🐱👓🐱🐱👤😺🙀😽🐱👓😹🙀😿😾😿🐱👓😹😾🐱🚀🐱👤🐱💻🐱💻🐱👓😾🐱👓🐱👓😺😾🐱👤🐱👤😺🐱👓😸🙀😼🐱👤🐈🐱👓😺🐱👤😼🙀😽🐱👓🐈😿😾🐱👤🐱🏍🐱👓😹😾😹😿😻🐱👓😹🙀🐱😾🐱🐱👓🐱🙀😼😿🐈🐱👓😹🐱👤😸😾😾🐱👓🐈😾😼😿😿🐱👓🐈🙀🐱👓🙀😻🐱👓😹🐱👤🙀🐱👤🐱🚀🐱👓🐈🐱👤🐱😿🐈🐱👓😸😾🙀🐱👤🐈🐱💻🐱👤🙀😹🐱👓😸😾😿🙀🐱👓🐱👓😸🐱👤🐱💻🙀🐱💻🐱👓🐱🙀😿🐱👤🐱👓🐱👓😺🙀😼😿😺🐱👓😸🐱👤😿🐱👤😹🐱👓😺🙀😻🐱👤😸🐱👓😺😿😿🙀😸🐱🏍😾😿🐈🐱👓😺😿😾😿🐱👤🐱👓🐈😾🐈😿🐱💻🐱💻😸🙀😸🐱👓😺😿🐱👓🐱👤😺🐱👓😺🙀🙀🙀🐱🐱👓😹🐱👤😸🙀🙀🐱👓😹🐱👤😼🐱👤🐱💻🐱👓🐱🙀🐱🐱👤😹🐱👓😺😿🐱🏍😾😹🐱👓😸🐱👤🐈🙀🐱👓🐱👓😺🐱👤😽🐱👤🐱👤🐱👓😺😿🐱🚀😾🐱🐱👓😺😾🐱🏍🙀🐱👓🐱👓😸🙀🐱💻😾😽🐱👓😸🐱👤🐱👓🐱👤🙀🐱👓😹😿😼😾😻🐱👓😹😿🙀🐱👤😻
-- main.go
package main
import (
"crypto/rand"
"encoding/hex"
"encoding/json"
"fmt"
"math/big"
"os"
"strings"
)
var CharSet = map[rune]string{
'0': "🐱", '1': "🐈", '2': "😸", '3': "😹",
'4': "😺", '5': "😻", '6': "😼", '7': "😽",
'8': "😾", '9': "😿", 'A': "🙀", 'B': "🐱👤",
'C': "🐱🏍", 'D': "🐱💻", 'E': "🐱👓", 'F': "🐱🚀",
}
func catify(input string, keys []int) string {
var keyedText string
var result string
for i, char := range input {
keyedText += string(rune(int(char) + keys[i]))
}
fmt.Printf("I2Keyed: %s\\n", keyedText)
hexEncoded := strings.ToUpper(hex.EncodeToString([]byte(keyedText)))
fmt.Printf("K2Hex: %s\\n", hexEncoded)
for _, rune := range hexEncoded {
result += CharSet[rune]
}
return result
}
func savePair(name, input, output string) {
inputFile, err := os.OpenFile(name+"_input.txt", os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0644)
if err != nil {
fmt.Println(err)
return
}
defer inputFile.Close()
outputFile, err := os.OpenFile(name+"_output.txt", os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0644)
if err != nil {
fmt.Println(err)
return
}
defer outputFile.Close()
if _, err := inputFile.Write([]byte(input)); err != nil {
fmt.Println(err)
return
}
if _, err := outputFile.Write([]byte(output)); err != nil {
fmt.Println(err)
return
}
}
func getKeys(length int) []int {
var keys = []int{}
keyFileName := fmt.Sprintf("keys_%d.json", length)
file, err := os.Open(keyFileName)
if err != nil {
for i := 0; i < length; i++ {
num, _ := rand.Int(rand.Reader, big.NewInt(60000))
keys = append(keys, int(num.Int64()))
}
keyFile, err := os.OpenFile(keyFileName, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0644)
if err != nil {
fmt.Println(err)
return []int{}
}
defer keyFile.Close()
encoded, _ := json.Marshal(keys)
keyFile.Write(encoded)
return keys
}
json.NewDecoder(file).Decode(&keys)
return keys
}
func main() {
input := "You fools! You will never get my catnip!!!!!!!"
keys := getKeys(len(input))
encoded := catify(input, keys)
savePair("example", input, encoded)
}
Tapi karena saya skill issue, saya convert ke python dengan bantuan gpt.
#main.py
import os
import json
import random
import string
from binascii import hexlify
# Karakter emoji untuk mapping
CHAR_SET = {
'0': "🐱", '1': "🐈", '2': "😸", '3': "😹",
'4': "😺", '5': "😻", '6': "😼", '7': "😽",
'8': "😾", '9': "😿", 'A': "🙀", 'B': "🐱👤",
'C': "🐱🏍", 'D': "🐱💻", 'E': "🐱👓", 'F': "🐱🚀"
}
def catify(input_text, keys):
# Tambahkan key ke setiap karakter input
keyed_text = ''.join(chr(ord(char) + keys[i]) for i, char in enumerate(input_text))
print(f"I2Keyed: {keyed_text}")
# Ubah menjadi representasi hex
hex_encoded = hexlify(keyed_text.encode()).decode().upper()
print(f"K2Hex: {hex_encoded}")
# Konversi hex menjadi emoji menggunakan CHAR_SET
result = ''.join(CHAR_SET[char] for char in hex_encoded)
return result
def save_pair(name, input_text, output_text):
# Simpan input ke file
with open(f"{name}_input.txt", "w") as input_file:
input_file.write(input_text)
# Simpan output ke file
with open(f"{name}_output.txt", "w") as output_file:
output_file.write(output_text)
def get_keys(length):
key_file_name = f"keys_{length}.json"
# Jika file key ada, baca isinya
if os.path.exists(key_file_name):
with open(key_file_name, "r") as file:
keys = json.load(file)
return keys
# Jika tidak ada, buat key baru
keys = [random.randint(0, 59999) for _ in range(length)]
# Simpan key ke file
with open(key_file_name, "w") as file:
json.dump(keys, file)
return keys
def main():
input_text = "You fools! You will never get my catnip!!!!!!!"
# Dapatkan kunci dengan panjang input
keys = get_keys(len(input_text))
# Encode input menjadi catified string
encoded = catify(input_text, keys)
# Simpan hasil encoding dan input ke file
save_pair("example", input_text, encoded)
if __name__ == "__main__":
main()
kita bisa bagi jadi tiga bagian, yakni catify, save_pair, dan get_keys
def get_keys(length):
key_file_name = f"keys_{length}.json"
# Jika file key ada, baca isinya
if os.path.exists(key_file_name):
with open(key_file_name, "r") as file:
keys = json.load(file)
return keys
# Jika tidak ada, buat key baru
keys = [random.randint(0, 59999) for _ in range(length)]
# Simpan key ke file
with open(key_file_name, "w") as file:
json.dump(keys, file)
return keys
Singkat saja, fungsi ini men-generate random key sesuai panjang pesan yang diterima dengan key ada di interval [0, 59999].
def catify(input_text, keys):
# Tambahkan key ke setiap karakter input
keyed_text = ''.join(chr(ord(char) + keys[i]) for i, char in enumerate(input_text))
print(f"I2Keyed: {keyed_text}")
# Ubah menjadi representasi hex
hex_encoded = hexlify(keyed_text.encode()).decode().upper()
print(f"K2Hex: {hex_encoded}")
# Konversi hex menjadi emoji menggunakan CHAR_SET
result = ''.join(CHAR_SET[char] for char in hex_encoded)
return result
Sementara, fungsi catify memetakan setiap character nya ke character lainnya sesuai key nya masing-masing, di encode ke hex, lalu setiap char hex nya di encode ke emoji.
def save_pair(name, input_text, output_text):
# Simpan input ke file
with open(f"{name}_input.txt", "w") as input_file:
input_file.write(input_text)
# Simpan output ke file
with open(f"{name}_output.txt", "w") as output_file:
output_file.write(output_text)
Jelas bahwa yang kita dapat dari save_pair adalah input_text nya dan output_text nya, namun kita cuma punya flag_output nya, nah dari probset dikasih tau kalau example_output dan flag_output menggunakan keys yang sama, jadi jelas len(flag_input) == len(text_input).