captcha-canvas/dist/security.js

A captcha generator by using skia-canvas module.

"use strict";
/**
 * Security utilities for CAPTCHA generation
 */
Object.defineProperty(exports, "__esModule", { value: true });
exports.constantTimeDelay = constantTimeDelay;
exports.generateSessionToken = generateSessionToken;
exports.hashSolution = hashSolution;
exports.verifySolution = verifySolution;
/**
 * Adds consistent timing to prevent timing attacks
 */
async function constantTimeDelay(minMs = 100, maxMs = 300) {
    const delay = Math.random() * (maxMs - minMs) + minMs;
    return new Promise(resolve => setTimeout(resolve, delay));
}
/**
 * Generates a secure session token for CAPTCHA verification
 */
function generateSessionToken() {
    const { randomBytes } = require('crypto');
    return randomBytes(32).toString('hex');
}
/**
 * Creates a hash of the CAPTCHA solution for secure storage
 */
function hashSolution(solution, salt) {
    const crypto = require('crypto');
    const actualSalt = salt || randomBytes(16).toString('hex');
    const hash = crypto.pbkdf2Sync(solution.toUpperCase(), actualSalt, 10000, 64, 'sha512');
    return `${actualSalt}:${hash.toString('hex')}`;
}
/**
 * Verifies a CAPTCHA solution against its hash
 */
function verifySolution(solution, hashedSolution) {
    const crypto = require('crypto');
    const [salt, hash] = hashedSolution.split(':');
    const verifyHash = crypto.pbkdf2Sync(solution.toUpperCase(), salt, 10000, 64, 'sha512');
    return hash === verifyHash.toString('hex');
}