<?php

/**

 * fsockopen HTTP transport

 *

 * @package Requests

 * @subpackage Transport

 */

/**

 * fsockopen HTTP transport

 *

 * @package Requests

 * @subpackage Transport

 */

class Requests_Transport_fsockopen implements Requests_Transport {

	/**

	 * Second to microsecond conversion

	 *

	 * @var integer

	 */

	const SECOND_IN_MICROSECONDS = 1000000;

	/**

	 * Raw HTTP data

	 *

	 * @var string

	 */

	public $headers = '';

	/**

	 * Stream metadata

	 *

	 * @var array Associative array of properties, see {@see https://secure.php.net/stream_get_meta_data}

	 */

	public $info;

	/**

	 * What's the maximum number of bytes we should keep?

	 *

	 * @var int|bool Byte count, or false if no limit.

	 */

	protected $max_bytes = false;

	protected $connect_error = '';

	/**

	 * Perform a request

	 *

	 * @throws Requests_Exception On failure to connect to socket (`fsockopenerror`)

	 * @throws Requests_Exception On socket timeout (`timeout`)

	 *

	 * @param string $url URL to request

	 * @param array $headers Associative array of request headers

	 * @param string|array $data Data to send either as the POST body, or as parameters in the URL for a GET/HEAD

	 * @param array $options Request options, see {@see Requests::response()} for documentation

	 * @return string Raw HTTP result

	 */

	public function request($url, $headers = array(), $data = array(), $options = array()) {

		$options['hooks']->dispatch('fsockopen.before_request');

		$url_parts = parse_url($url);

		if (empty($url_parts)) {

			throw new Requests_Exception('Invalid URL.', 'invalidurl', $url);

		}

		$host                     = $url_parts['host'];

		$context                  = stream_context_create();

		$verifyname               = false;

		$case_insensitive_headers = new Requests_Utility_CaseInsensitiveDictionary($headers);

		// HTTPS support

		if (isset($url_parts['scheme']) && strtolower($url_parts['scheme']) === 'https') {

			$remote_socket = 'ssl://' . $host;

			if (!isset($url_parts['port'])) {

				$url_parts['port'] = 443;

			}

			$context_options = array(

				'verify_peer'       => true,

				'capture_peer_cert' => true,

			);

			$verifyname      = true;

			// SNI, if enabled (OpenSSL >=0.9.8j)

			// phpcs:ignore PHPCompatibility.Constants.NewConstants.openssl_tlsext_server_nameFound

			if (defined('OPENSSL_TLSEXT_SERVER_NAME') && OPENSSL_TLSEXT_SERVER_NAME) {

				$context_options['SNI_enabled'] = true;

				if (isset($options['verifyname']) && $options['verifyname'] === false) {

					$context_options['SNI_enabled'] = false;

				}

			}

			if (isset($options['verify'])) {

				if ($options['verify'] === false) {

					$context_options['verify_peer']      = false;

					$context_options['verify_peer_name'] = false;

					$verifyname                          = false;

				}

				elseif (is_string($options['verify'])) {

					$context_options['cafile'] = $options['verify'];

				}

			}

			if (isset($options['verifyname']) && $options['verifyname'] === false) {

				$context_options['verify_peer_name'] = false;

				$verifyname                          = false;

			}

			stream_context_set_option($context, array('ssl' => $context_options));

		}

		else {

			$remote_socket = 'tcp://' . $host;

		}

		$this->max_bytes = $options['max_bytes'];

		if (!isset($url_parts['port'])) {

			$url_parts['port'] = 80;

		}

		$remote_socket .= ':' . $url_parts['port'];

		// phpcs:ignore WordPress.PHP.DevelopmentFunctions.error_log_set_error_handler

		set_error_handler(array($this, 'connect_error_handler'), E_WARNING | E_NOTICE);

		$options['hooks']->dispatch('fsockopen.remote_socket', array(&$remote_socket));

		$socket = stream_socket_client($remote_socket, $errno, $errstr, ceil($options['connect_timeout']), STREAM_CLIENT_CONNECT, $context);

		restore_error_handler();

		if ($verifyname && !$this->verify_certificate_from_context($host, $context)) {

			throw new Requests_Exception('SSL certificate did not match the requested domain name', 'ssl.no_match');

		}

		if (!$socket) {

			if ($errno === 0) {

				// Connection issue

				throw new Requests_Exception(rtrim($this->connect_error), 'fsockopen.connect_error');

			}

			throw new Requests_Exception($errstr, 'fsockopenerror', null, $errno);

		}

		$data_format = $options['data_format'];

		if ($data_format === 'query') {

			$path = self::format_get($url_parts, $data);

			$data = '';

		}

		else {

			$path = self::format_get($url_parts, array());

		}

		$options['hooks']->dispatch('fsockopen.remote_host_path', array(&$path, $url));

		$request_body = '';

		$out          = sprintf("%s %s HTTP/%.1F\r\n", $options['type'], $path, $options['protocol_version']);

		if ($options['type'] !== Requests::TRACE) {

			if (is_array($data)) {

				$request_body = http_build_query($data, '', '&');

			}

			else {

				$request_body = $data;

			}

			// Always include Content-length on POST requests to prevent

			// 411 errors from some servers when the body is empty.

			if (!empty($data) || $options['type'] === Requests::POST) {

				if (!isset($case_insensitive_headers['Content-Length'])) {

					$headers['Content-Length'] = strlen($request_body);

				}

				if (!isset($case_insensitive_headers['Content-Type'])) {

					$headers['Content-Type'] = 'application/x-www-form-urlencoded; charset=UTF-8';

				}

			}

		}

		if (!isset($case_insensitive_headers['Host'])) {

			$out .= sprintf('Host: %s', $url_parts['host']);

			if ((strtolower($url_parts['scheme']) === 'http' && $url_parts['port'] !== 80) || (strtolower($url_parts['scheme']) === 'https' && $url_parts['port'] !== 443)) {

				$out .= ':' . $url_parts['port'];

			}

			$out .= "\r\n";

		}

		if (!isset($case_insensitive_headers['User-Agent'])) {

			$out .= sprintf("User-Agent: %s\r\n", $options['useragent']);

		}

		$accept_encoding = $this->accept_encoding();

		if (!isset($case_insensitive_headers['Accept-Encoding']) && !empty($accept_encoding)) {

			$out .= sprintf("Accept-Encoding: %s\r\n", $accept_encoding);

		}

		$headers = Requests::flatten($headers);

		if (!empty($headers)) {

			$out .= implode("\r\n", $headers) . "\r\n";

		}

		$options['hooks']->dispatch('fsockopen.after_headers', array(&$out));

		if (substr($out, -2) !== "\r\n") {

			$out .= "\r\n";

		}

		if (!isset($case_insensitive_headers['Connection'])) {

			$out .= "Connection: Close\r\n";

		}

		$out .= "\r\n" . $request_body;

		$options['hooks']->dispatch('fsockopen.before_send', array(&$out));

		fwrite($socket, $out);

		$options['hooks']->dispatch('fsockopen.after_send', array($out));

		if (!$options['blocking']) {

			fclose($socket);

			$fake_headers = '';

			$options['hooks']->dispatch('fsockopen.after_request', array(&$fake_headers));

			return '';

		}

		$timeout_sec = (int) floor($options['timeout']);

		if ($timeout_sec === $options['timeout']) {

			$timeout_msec = 0;

		}

		else {

			$timeout_msec = self::SECOND_IN_MICROSECONDS * $options['timeout'] % self::SECOND_IN_MICROSECONDS;

		}

		stream_set_timeout($socket, $timeout_sec, $timeout_msec);

		$response   = '';

		$body       = '';

		$headers    = '';

		$this->info = stream_get_meta_data($socket);

		$size       = 0;

		$doingbody  = false;

		$download   = false;

		if ($options['filename']) {

			$download = fopen($options['filename'], 'wb');

		}

		while (!feof($socket)) {

			$this->info = stream_get_meta_data($socket);

			if ($this->info['timed_out']) {

				throw new Requests_Exception('fsocket timed out', 'timeout');

			}

			$block = fread($socket, Requests::BUFFER_SIZE);

			if (!$doingbody) {

				$response .= $block;

				if (strpos($response, "\r\n\r\n")) {

					list($headers, $block) = explode("\r\n\r\n", $response, 2);

					$doingbody             = true;

				}

			}

			// Are we in body mode now?

			if ($doingbody) {

				$options['hooks']->dispatch('request.progress', array($block, $size, $this->max_bytes));

				$data_length = strlen($block);

				if ($this->max_bytes) {

					// Have we already hit a limit?

					if ($size === $this->max_bytes) {

						continue;

					}

					if (($size + $data_length) > $this->max_bytes) {

						// Limit the length

						$limited_length = ($this->max_bytes - $size);

						$block          = substr($block, 0, $limited_length);

					}

				}

				$size += strlen($block);

				if ($download) {

					fwrite($download, $block);

				}

				else {

					$body .= $block;

				}

			}

		}

		$this->headers = $headers;

		if ($download) {

			fclose($download);

		}

		else {

			$this->headers .= "\r\n\r\n" . $body;

		}

		fclose($socket);

		$options['hooks']->dispatch('fsockopen.after_request', array(&$this->headers, &$this->info));

		return $this->headers;

	}

	/**

	 * Send multiple requests simultaneously

	 *

	 * @param array $requests Request data (array of 'url', 'headers', 'data', 'options') as per {@see Requests_Transport::request}

	 * @param array $options Global options, see {@see Requests::response()} for documentation

	 * @return array Array of Requests_Response objects (may contain Requests_Exception or string responses as well)

	 */

	public function request_multiple($requests, $options) {

		$responses = array();

		$class     = get_class($this);

		foreach ($requests as $id => $request) {

			try {

				$handler        = new $class();

				$responses[$id] = $handler->request($request['url'], $request['headers'], $request['data'], $request['options']);

				$request['options']['hooks']->dispatch('transport.internal.parse_response', array(&$responses[$id], $request));

			}

			catch (Requests_Exception $e) {

				$responses[$id] = $e;

			}

			if (!is_string($responses[$id])) {

				$request['options']['hooks']->dispatch('multiple.request.complete', array(&$responses[$id], $id));

			}

		}

		return $responses;

	}

	/**

	 * Retrieve the encodings we can accept

	 *

	 * @return string Accept-Encoding header value

	 */

	protected static function accept_encoding() {

		$type = array();

		if (function_exists('gzinflate')) {

			$type[] = 'deflate;q=1.0';

		}

		if (function_exists('gzuncompress')) {

			$type[] = 'compress;q=0.5';

		}

		$type[] = 'gzip;q=0.5';

		return implode(', ', $type);

	}

	/**

	 * Format a URL given GET data

	 *

	 * @param array $url_parts

	 * @param array|object $data Data to build query using, see {@see https://secure.php.net/http_build_query}

	 * @return string URL with data

	 */

	protected static function format_get($url_parts, $data) {

		if (!empty($data)) {

			if (empty($url_parts['query'])) {

				$url_parts['query'] = '';

			}

			$url_parts['query'] .= '&' . http_build_query($data, '', '&');

			$url_parts['query']  = trim($url_parts['query'], '&');

		}

		if (isset($url_parts['path'])) {

			if (isset($url_parts['query'])) {

				$get = $url_parts['path'] . '?' . $url_parts['query'];

			}

			else {

				$get = $url_parts['path'];

			}

		}

		else {

			$get = '/';

		}

		return $get;

	}

	/**

	 * Error handler for stream_socket_client()

	 *

	 * @param int $errno Error number (e.g. E_WARNING)

	 * @param string $errstr Error message

	 */

	public function connect_error_handler($errno, $errstr) {

		// Double-check we can handle it

		if (($errno & E_WARNING) === 0 && ($errno & E_NOTICE) === 0) {

			// Return false to indicate the default error handler should engage

			return false;

		}

		$this->connect_error .= $errstr . "\n";

		return true;

	}

	/**

	 * Verify the certificate against common name and subject alternative names

	 *

	 * Unfortunately, PHP doesn't check the certificate against the alternative

	 * names, leading things like 'https://www.github.com/' to be invalid.

	 * Instead

	 *

	 * @see https://tools.ietf.org/html/rfc2818#section-3.1 RFC2818, Section 3.1

	 *

	 * @throws Requests_Exception On failure to connect via TLS (`fsockopen.ssl.connect_error`)

	 * @throws Requests_Exception On not obtaining a match for the host (`fsockopen.ssl.no_match`)

	 * @param string $host Host name to verify against

	 * @param resource $context Stream context

	 * @return bool