captcha-canvas/dist/validation.js

A captcha generator by using skia-canvas module.

"use strict";
/**
 * Input validation utilities for CAPTCHA generation parameters
 */
Object.defineProperty(exports, "__esModule", { value: true });
exports.validateDimensions = validateDimensions;
exports.validateText = validateText;
exports.validateColor = validateColor;
exports.validateNumericRange = validateNumericRange;
/**
 * Validates and sanitizes dimension parameters
 */
function validateDimensions(width, height) {
    // Prevent extremely large images that could cause memory issues
    const MAX_DIMENSION = 2000;
    const MIN_DIMENSION = 50;
    if (!Number.isInteger(width) || !Number.isInteger(height)) {
        throw new Error('Dimensions must be integers');
    }
    if (width < MIN_DIMENSION || width > MAX_DIMENSION) {
        throw new Error(`Width must be between ${MIN_DIMENSION} and ${MAX_DIMENSION} pixels`);
    }
    if (height < MIN_DIMENSION || height > MAX_DIMENSION) {
        throw new Error(`Height must be between ${MIN_DIMENSION} and ${MAX_DIMENSION} pixels`);
    }
    return { width, height };
}
/**
 * Validates text content for security
 */
function validateText(text) {
    if (typeof text !== 'string') {
        throw new Error('Text must be a string');
    }
    // Prevent excessively long text
    if (text.length > 50) {
        throw new Error('Text length cannot exceed 50 characters');
    }
    // Remove potentially dangerous characters
    const sanitized = text.replace(/[<>'"&]/g, '');
    if (sanitized.length === 0) {
        throw new Error('Text cannot be empty after sanitization');
    }
    return sanitized;
}
/**
 * Validates color values
 */
function validateColor(color) {
    if (typeof color !== 'string') {
        throw new Error('Color must be a string');
    }
    // Basic color validation (hex, rgb, named colors)
    const colorRegex = /^(#[0-9A-Fa-f]{3,8}|rgb\([^)]+\)|rgba\([^)]+\)|[a-zA-Z]+)$/;
    if (!colorRegex.test(color)) {
        throw new Error('Invalid color format');
    }
    return color;
}
/**
 * Validates numeric parameters with bounds
 */
function validateNumericRange(value, min, max, name) {
    if (typeof value !== 'number' || !Number.isFinite(value)) {
        throw new Error(`${name} must be a finite number`);
    }
    if (value < min || value > max) {
        throw new Error(`${name} must be between ${min} and ${max}`);
    }
    return value;
}