PanicAttack.php

<?php

/**
 * SPDX-License-Identifier: MIT
 * Copyright (c) 2017-2018 Tobias Reich
 * Copyright (c) 2018-2026 LycheeOrg.
 */

/**
 * Basic PanicAttack class.
 *
 * Used only in case of emergency: e.g. vendor not found
 */
class PanicAttack
{
	private $title = '';
	private $code = 0;
	private $message = '';

	/**
	 * Check if all the elements of the array are in a string.
	 *
	 * @param string $haystack string to check against
	 * @param array  $needles  array of needles to check
	 *
	 * @return bool
	 */
	private function contains(string $haystack, array $needles)
	{
		foreach ($needles as $needle) {
			if (strpos($haystack, $needle) === false) {
				return false;
			}
		}

		return true;
	}

	/**
	 * Display errors as nice page.
	 *
	 * This function is an EXIT.
	 */
	private function displaySimpleError()
	{
		$error_display = file_get_contents(__DIR__ . '/../simple_error_template.html');
		$replacing = [
			'$title' => $this->title,
			'$code' => $this->code,
			'$message' => $this->message,
		];
		http_response_code($this->code);
		echo strtr($error_display, $replacing);
		exit;
	}

	/**
	 * Called from ../index.php.
	 */
	public function root()
	{
		$this->title = 'ROOT';
		$this->code = 403;
		$this->message = '<span class="important">This is the root directory and MUST NOT BE PUBLICLY ACCESSIBLE.</span><br>
		To access Lychee, go <a href="public/">here</a>.';
		$this->displaySimpleError();
	}

	/**
	 * Called from bootstrap/initialize.php if apache rewrite is not enabled.
	 */
	public function apacheRewrite()
	{
		$this->title = 'mod_rewrite is not enabled';
		$this->code = 503;
		$this->message = 'You are using apache but <code>mod_rewrite</code> is not enabled.<br>
		Please do: <code>a2enmod rewrite</code>';
		$this->displaySimpleError();
	}

	/*
	 |--------------------------------------------------------------------------
	 | Catch error where composer is loading properly.
	 |--------------------------------------------------------------------------
	 | When composer has not been run yet the ../vendor/autoload.php file does
	 | not exists. We check if the error message contains 'require' and
	 | 'vendor/autoload', in such case we display a nice error.
	 */
	public function composerVendorNotFound()
	{
		$this->title = 'vendor/autoload.php not found';
		$this->code = 503;
		$this->message = '<code>../vendor/autoload.php</code> not found.<br>
		Please do: <code>composer install --no-dev --prefer-dist</code>';
		$this->displaySimpleError();
	}

	/*
	 |--------------------------------------------------------------------------
	 | Catch error on missing access rights.
	 |--------------------------------------------------------------------------
	 */
	public function checkAccessRightsViews()
	{
		$this->title = 'Invalid access rights';
		$this->code = 503;
		$this->message = '<code>../storage</code> and sub-directories are not writable.<br>
		Please set the proper access rights.';
		$this->displaySimpleError();
	}

	/*
	 |--------------------------------------------------------------------------
	 | Catch error on missing access rights.
	 |--------------------------------------------------------------------------
	 */
	public function checkAccessRightsEnv()
	{
		$this->title = 'Invalid access rights';
		$this->code = 503;
		$this->message = '<code>.env</code> is not writable.<br>
		Please set the proper access rights.';
		$this->displaySimpleError();
	}

	/*
	 |--------------------------------------------------------------------------
	 | Catch error on missing ldap extension.
	 |--------------------------------------------------------------------------
	 | When the ldap extension is not loaded, we display a nice error.
	 | This is a sanity check to prevent the user from seeing a blank page with an error in the top left
	*/
	public function ldap() {
		$this->title = 'Missing PHP Extension';
		$this->code = 500;
		$this->message = 'The PHP extension "ldap" is required but not loaded. Please install and enable it to run Lychee.';
		$this->displaySimpleError();
	}


	/**
	 *  dispatcher.
	 */
	public function handle(string $error_message)
	{
		$handling = [
			'composerVendorNotFound' => ['require', 'Failed opening required', 'vendor/autoload.php'],
			'checkAccessRightsViews' => ['file_put_contents', 'storage/framework/views', 'Permission denied'],
			'checkAccessRightsEnv' => ['file_put_contents', '.env'],
		];

		foreach ($handling as $fun => $needles) {
			if ($this->contains($error_message, $needles)) {
				$this->$fun();
			}
		}
	}
}