Key cripto lab04

Descifrar mediante 3DES

You will need to install an extension such as Tampermonkey, Greasemonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey to install this script.

You will need to install an extension such as Tampermonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Userscripts to install this script.

You will need to install an extension such as Tampermonkey to install this script.

You will need to install a user script manager extension to install this script.

(I already have a user script manager, let me install it!)

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

(I already have a user style manager, let me install it!)

// ==UserScript==
// @name         Key cripto lab04
// @namespace    http://tampermonkey.net/
// @version      2024-06-13
// @description  Descifrar mediante 3DES
// @author       Franco Ramirez
// @match        https://*.tiiny.site/
// @icon         data:image/gif;base64,R0lGODlhAQABAAAAACH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==
// @require      https://cdnjs.cloudflare.com/ajax/libs/crypto-js/4.2.0/crypto-js.min.js#sha384-mgWScxWVKP8F7PBbpNp7i/aSb17kN0LcifBpahAplF3Mn0GR4/u1oMpWIm2rD8yY
// @grant        none
// @license MIT
// ==/UserScript==

(function() {
    'use strict';

    function decryptMessage(encryptedMessage, key) {
        // Convertir la clave en un formato adecuado
        const keyHex = CryptoJS.enc.Utf8.parse(key);

        // Descifrar el mensaje
        const decrypted = CryptoJS.TripleDES.decrypt({
            ciphertext: CryptoJS.enc.Base64.parse(encryptedMessage)
        }, keyHex, {
            mode: CryptoJS.mode.ECB,
            padding: CryptoJS.pad.Pkcs7
        });

        // Convertir el mensaje descifrado a texto
        const decryptedText = decrypted.toString(CryptoJS.enc.Utf8);

        return decryptedText;
    }

    function getKey(){

        // Se obtiene el texto completo
        const bodyText = document.body.innerText;

        // Trae todas las mayusculas y las concatena
        const key = bodyText.match(/[A-Z]/g).join('');

        // Retorna la llave encontrada
        return key;
    }

    function getMsgs(){

        const divs = document.querySelectorAll('div');
        const pattern = /^M\d+$/;

        const filteredDivs = Array.from(divs).filter(div => pattern.test(div.className));

        return filteredDivs;

    }


    window.addEventListener('load', function() {

        var messages_enc = [];
        var messages_dec = [];

        const key = getKey();

        const divs = getMsgs();

        console.log('La llave es:', key);

        console.log("Los mensajes cifrados son:", divs.length);


        divs.forEach((div) => {
            const dec = decryptMessage(div.id, key);
            messages_enc.push(div.id);
            messages_dec.push(dec);
        });


        for(let i = 0; i < messages_enc.length; i++){
            console.log(`M${i+1}: `, messages_enc[i], messages_dec[i]);
            const p = document.createElement('p');
            p.textContent = messages_dec[i];
            divs[i].appendChild(p);
        }
    });
})();