Charset Generator

Overview

This package is designed to make CTF char-by-char bruteforce simpler.

Installation

pip install charset-generator

Documentation

Charsets can be generated from string.printable using gen_charset.

If frequency_sorted is True, then it will be ordered based on frequency, with the most frequent characters appearing first.

gen_charset(regex: str, frequency_sorted: bool = False) -> str:

Characters can be produced from a generator using yielding.yield_charset.

If allow_interruptions is True, then the user can press the interrupt_key, to temporarily take over, allowing them to choose the next character. This is useful for cases where the user can predict the next character faster than it would take to bruteforce through the charset.

yielding.yield_charset(regex: str, frequency_sorted: bool = False, allow_interruptions: bool = False, interrupt_key: str = "esc") -> Generator[str, None, None]:

ai.assess_predictability and ai.predict_next_char are both highly experimental.

Together, they allow you to use OpenAI to predict the next character of a flag, given some prefix known_text.

Use these with caution.

ai.assess_predictability(
    known_text: str, openai_api_key: str, model: str = "gpt-4o-mini",
    role: str = "You are a professional CTF hacker.",
    prompt: str = (
        "You will receive the first part of a flag. Analyze it and decide how confident you are in predicting "
        "the next character with 100% accuracy. Provide a brief explanation, then on a new line output exactly "
        "'~~' followed by one of these options: 'Very confident', 'Somewhat confident', or 'Not confident'.\n"
        "Example:\n"
        "The flag starts with 'CTF{' but many characters could follow.\n"
        "~~Not confident\n"
    )
) -> str

ai.predict_next_char(
    known_text: str, openai_api_key: str, banned_chars: List[str] = [], model: str = "gpt-4o-mini",
    role: str = "You are a professional CTF hacker.",
    prompt: str = (
        "You will receive the first part of a flag. Predict the next character with no extra text. "
        "Your answer must be exactly one character. Note that flags may include leet speak or underscores.\n"
    )
) -> str