CyberChef/src/core/operations/FromBase64.mjs

/**
 * @author n1474335 [n1474335@gmail.com]
 * @copyright Crown Copyright 2016
 * @license Apache-2.0
 */

import Operation from "../Operation";
import {fromBase64, ALPHABET_OPTIONS} from "../lib/Base64";

/**
 * From Base64 operation
 */
class FromBase64 extends Operation {

    /**
     * FromBase64 constructor
     */
    constructor() {
        super();

        this.name = "From Base64";
        this.module = "Default";
        this.description = "Base64 is a notation for encoding arbitrary byte data using a restricted set of symbols that can be conveniently used by humans and processed by computers.<br><br>This operation decodes data from an ASCII Base64 string back into its raw format.<br><br>e.g. <code>aGVsbG8=</code> becomes <code>hello</code>";
        this.inputType = "string";
        this.outputType = "byteArray";
        this.args = [
            {
                name: "Alphabet",
                type: "editableOption",
                value: ALPHABET_OPTIONS
            },
            {
                name: "Remove non-alphabet chars",
                type: "boolean",
                value: true
            }
        ];
    }

    /**
     * @param {ArrayBuffer} input
     * @param {Object[]} args
     * @returns {string}
     */
    run(input, args) {
        const [alphabet, removeNonAlphChars] = args;

        return fromBase64(input, alphabet, "byteArray", removeNonAlphChars);
    }

    /**
     * Highlight to Base64
     *
     * @param {Object[]} pos
     * @param {number} pos[].start
     * @param {number} pos[].end
     * @param {Object[]} args
     * @returns {Object[]} pos
     */
    highlight(pos, args) {
        pos[0].start = Math.ceil(pos[0].start / 4 * 3);
        pos[0].end = Math.floor(pos[0].end / 4 * 3);
        return pos;
    }

    /**
     * Highlight from Base64
     *
     * @param {Object[]} pos
     * @param {number} pos[].start
     * @param {number} pos[].end
     * @param {Object[]} args
     * @returns {Object[]} pos
     */
    highlightReverse(pos, args) {
        pos[0].start = Math.floor(pos[0].start / 3 * 4);
        pos[0].end = Math.ceil(pos[0].end / 3 * 4);
        return pos;
    }
}

export default FromBase64;