> For the complete documentation index, see [llms.txt](https://0xss0rz.gitbook.io/0xss0rz/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://0xss0rz.gitbook.io/0xss0rz/ctf/steganography-1/methods.md).

# Methods

## Paddinganography

{% embed url="<https://inshallhack.org/paddinganography/>" %}

```
#Source: https://gist.githubusercontent.com/dhondta/90a07d9d106775b0cd29bb51ffe15954/raw/e85a13e7fe1805daa314d776926df470d344aca6/paddinganograph.py

#!/usr/bin/python3
# -*- coding: UTF-8 -*-
import math
from tinyscript import *


__author__ = "Alexandre D'Hondt"
__version__ = "1.2"
__copyright__ = "A. D'Hondt"
__license__ = "agpl-3.0"
__reference__ = "https://inshallhack.org/paddinganography/"
__doc__ = """
This tool allows to unhide data hidden in base32/base64 strings. It can take a
 PNG or JPG in input to retrieve an EXIF value as the input data.
"""
__examples__ = [
    "-s . -f \"Comment\" < image.jpg > base32.enc",
    "-e base32 < base32.enc"
]


DEF_BASE64 = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"
DEF_BASE32 = "ABCDEFGHIJKLMNOPQRSTUVWXYZ234567"


def exif(raw_data, key):
    t = TempPath().tempfile().name
    with open(str(t), 'wb') as f:
        f.write(raw_data)
    logger.debug("Getting EXIF data...")
    exif = subprocess.check_output(["exiftool", str(t)])
    exif = codecs.decode(exif, "utf-8")
    exif = {l.split(':', 1)[0].strip(): l.split(':', 1)[1].strip() \
            for l in exif.split('\n') if l.strip() != ""}
    return exif if not key else exif[key]


def unhide(encoded, encoding="base64", charset=None, sep=".", pad="=", n_pad=8):
    try:
        charset = (charset or \
                   globals()["DEF_{}".format(encoding.upper())]).strip()
    except NameError:
        raise ValueError("Bad encoding")
    logger.debug("Unhidding data...")
    bits = ""
    for token in encoded.split(b(sep)):
        bits += unhide_bits(token.strip(), charset, pad, n_pad) or ""
    return "".join(ts.bin2str(bits[i:i+8]) for i in range(0, len(bits), 8))


def unhide_bits(encoded, charset, pad="=", n_pad=8):
    def __gcd(a,b):
        while b > 0:
            a, b = b, a % b
        return a
    padding = encoded.count(b(pad))
    n_repr = int(math.ceil(math.log(len(charset), 2)))
    w_len  = n_repr * n_pad / __gcd(n_repr, n_pad)
    n_char = int(math.ceil(float(w_len) / n_repr))
    if encoded == "" or len(encoded) % n_char != 0 or padding == 0:
        return
    unused = {n: int(w_len - n * n_repr) % n_pad for n in range(n_char)}
    b_val  = bin(b(charset).index(encoded.rstrip(b(pad))[-1]))[2:].zfill(n_repr)
    return b_val[-unused[padding]:]


if __name__ == '__main__':
    parser.add_argument("-c", "--charset",
                        help="characters set")
    parser.add_argument("-e", "--encoding", choices=["base32", "base64"],
                        default="base64", help="character encoding")
    parser.add_argument("-f", "--exif-field", dest="exif", default="Comment",
                        help="EXIF metadata field to be selected")
    parser.add_argument("-p", "--padding-char", default="=",
                        help="padding character")
    parser.add_argument("-s", "--separator", default="\n",
                        help="base-encoded token separator")
    initialize()
    data = b("").join(l for l in ts.stdin_pipe())
    if data.startswith(b("\x89PNG")) or data.startswith(b("\xff\xd8\xff\xe0")):
        data = exif(data, args.exif)
    print(unhide(data, args.encoding, args.charset, args.separator))
```

```
#Base 64 paddinganogarphy
#Source: http://delimitry.blogspot.com/2014/02/olympic-ctf-2014-find-da-key-writeup.html

def get_base64_diff_value(s1, s2):
 base64chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'
 res = 0
 for i in xrange(len(s1)):
  if s1[i] != s2[i]:
   return abs(base64chars.index(s1[i]) - base64chars.index(s2[i]))
 return res

def solve_stego():
 with open('stego.txt', 'rb') as f:
  file_lines = f.readlines()

 bin_str = ''
 for line in file_lines:
  steg_line = line.replace('\n', '')
  norm_line = line.replace('\n', '').decode('base64').encode('base64').replace('\n', '')

  diff = get_base64_diff_value(steg_line, norm_line)
  pads_num = steg_line.count('=')
  if diff:
   bin_str += bin(diff)[2:].zfill(pads_num * 2)
  else:
   bin_str += '0' * pads_num * 2

 res_str = ''
 for i in xrange(0, len(bin_str), 8):
  res_str += chr(int(bin_str[i:i+8], 2))
 print res_str

solve_stego()
```

## Whitespace language

{% embed url="<https://www.dcode.fr/whitespace-language>" %}

{% embed url="<http://manpages.ubuntu.com/manpages/bionic/man1/stegsnow.1.html>" %}


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://0xss0rz.gitbook.io/0xss0rz/ctf/steganography-1/methods.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.