Proyectos de Subversion Moodle

<?php

namespace PhpXmlRpc\Helper;

use PhpXmlRpc\Exception\HttpException;

use PhpXmlRpc\PhpXmlRpc;

use PhpXmlRpc\Traits\LoggerAware;

class Http

{

    use LoggerAware;

    /**

     * Decode a string that is encoded with "chunked" transfer encoding as defined in rfc2068 par. 19.4.6.

     * Code shamelessly stolen from nusoap library by Dietrich Ayala.

     * @internal this function will become protected in the future

     *

     * @param string $buffer the string to be decoded

     * @return string

     */

    public static function decodeChunked($buffer)

    {

        // length := 0

        $length = 0;

        $new = '';

        // read chunk-size, chunk-extension (if any) and crlf

        // get the position of the linebreak

        $chunkEnd = strpos($buffer, "\r\n") + 2;

        $temp = substr($buffer, 0, $chunkEnd);

        $chunkSize = hexdec(trim($temp));

        $chunkStart = $chunkEnd;

        while ($chunkSize > 0) {

            $chunkEnd = strpos($buffer, "\r\n", $chunkStart + $chunkSize);

            // just in case we got a broken connection

            if ($chunkEnd == false) {

                $chunk = substr($buffer, $chunkStart);

                // append chunk-data to entity-body

                $new .= $chunk;

                $length += strlen($chunk);

                break;

            }

            // read chunk-data and crlf

            $chunk = substr($buffer, $chunkStart, $chunkEnd - $chunkStart);

            // append chunk-data to entity-body

            $new .= $chunk;

            // length := length + chunk-size

            $length += strlen($chunk);

            // read chunk-size and crlf

            $chunkStart = $chunkEnd + 2;

            $chunkEnd = strpos($buffer, "\r\n", $chunkStart) + 2;

            if ($chunkEnd == false) {

                break; // just in case we got a broken connection

            }

            $temp = substr($buffer, $chunkStart, $chunkEnd - $chunkStart);

            $chunkSize = hexdec(trim($temp));

            $chunkStart = $chunkEnd;

        }

        return $new;

    }

    /**

     * Parses HTTP an http response's headers and separates them from the body.

     *

     * @param string $data the http response, headers and body. It will be stripped of headers

     * @param bool $headersProcessed when true, we assume that response inflating and dechunking has been already carried out

     * @param int $debug when > 0, logs to screen messages detailing info about the parsed data

     * @return array with keys 'headers', 'cookies', 'raw_data' and 'status_code'

     * @throws HttpException

     *

     * @todo if $debug is < 0, we could avoid populating 'raw_data' and 'headers' in the returned value - but that would

     *       be a weird API...

     */

    public function parseResponseHeaders(&$data, $headersProcessed = false, $debug = 0)

    {

        $httpResponse = array('raw_data' => $data, 'headers'=> array(), 'cookies' => array(), 'status_code' => null);

        // Support "web-proxy-tunnelling" connections for https through proxies

        if (preg_match('/^HTTP\/1\.[0-1] 200 Connection established/', $data)) {

            // Look for CR/LF or simple LF as line separator (even though it is not valid http)

            $pos = strpos($data, "\r\n\r\n");

            if ($pos || is_int($pos)) {

                $bd = $pos + 4;

            } else {

                $pos = strpos($data, "\n\n");

                if ($pos || is_int($pos)) {

                    $bd = $pos + 2;

                } else {

                    // No separation between response headers and body: fault?

                    $bd = 0;

                }

            }

            if ($bd) {

                // this filters out all http headers from proxy. maybe we could take them into account, too?

                $data = substr($data, $bd);

            } else {

                $this->getLogger()->error('XML-RPC: ' . __METHOD__ . ': HTTPS via proxy error, tunnel connection possibly failed');

                throw new HttpException(PhpXmlRpc::$xmlrpcstr['http_error'] . ' (HTTPS via proxy error, tunnel connection possibly failed)', PhpXmlRpc::$xmlrpcerr['http_error']);

            }

        }

        // Strip HTTP 1.1 100 Continue header if present

        while (preg_match('/^HTTP\/1\.1 1[0-9]{2} /', $data)) {

            $pos = strpos($data, 'HTTP', 12);

            // server sent a Continue header without any (valid) content following...

            // give the client a chance to know it

            if (!$pos && !is_int($pos)) {

                /// @todo this construct works fine in php 3, 4 and 5 - 8; would it not be enough to have !== false now ?

                break;

            }

            $data = substr($data, $pos);

        }

        // When using Curl to query servers using Digest Auth, we get back a double set of http headers.

        // Same when following redirects

        // We strip out the 1st...

        /// @todo we should let the caller know that there was a redirect involved

        if ($headersProcessed && preg_match('/^HTTP\/[0-9](?:\.[0-9])? (?:401|30[1278]) /', $data)) {

            if (preg_match('/(\r?\n){2}HTTP\/[0-9](?:\.[0-9])? 200 /', $data)) {

                $data = preg_replace('/^HTTP\/[0-9](?:\.[0-9])? (?:401|30[1278]) .+?(?:\r?\n){2}(HTTP\/[0-9.]+ 200 )/s', '$1', $data, 1);

            }

        }

        if (preg_match('/^HTTP\/([0-9](?:\.[0-9])?) ([0-9]{3}) /', $data, $matches)) {

            $httpResponse['protocol_version'] = $matches[1];

            $httpResponse['status_code'] = $matches[2];

        }

        if ($httpResponse['status_code'] !== '200') {

            $errstr = substr($data, 0, strpos($data, "\n") - 1);

            $this->getLogger()->error('XML-RPC: ' . __METHOD__ . ': HTTP error, got response: ' . $errstr);

            throw new HttpException(PhpXmlRpc::$xmlrpcstr['http_error'] . ' (' . $errstr . ')', PhpXmlRpc::$xmlrpcerr['http_error'], null, $httpResponse['status_code']);

        }

        // be tolerant to usage of \n instead of \r\n to separate headers and data (even though it is not valid http)

        $pos = strpos($data, "\r\n\r\n");

        if ($pos || is_int($pos)) {

            $bd = $pos + 4;

        } else {

            $pos = strpos($data, "\n\n");

            if ($pos || is_int($pos)) {

                $bd = $pos + 2;

            } else {

                // No separation between response headers and body: fault?

                // we could take some action here instead of going on...

                $bd = 0;

            }

        }

        // be tolerant to line endings, and extra empty lines

        $ar = preg_split("/\r?\n/", trim(substr($data, 0, $pos)));

        foreach ($ar as $line) {

            // take care of (multi-line) headers and cookies

            $arr = explode(':', $line, 2);

            if (count($arr) > 1) {

                /// @todo according to https://www.rfc-editor.org/rfc/rfc7230#section-3.2.4, we should reject with error

                ///       400 any messages where a space is present between the header name and colon

                $headerName = strtolower(trim($arr[0]));

                if ($headerName == 'set-cookie') {

                    $cookie = $arr[1];

                    // glue together all received cookies, using a comma to separate them (same as php does with getallheaders())

                    if (isset($httpResponse['headers'][$headerName])) {

                        $httpResponse['headers'][$headerName] .= ', ' . trim($cookie);

                    } else {

                        $httpResponse['headers'][$headerName] = trim($cookie);

                    }

                    // parse cookie attributes, in case user wants to correctly honour them

                    // @todo support for server sending multiple time cookie with same name, but using different PATHs

                    $cookie = explode(';', $cookie);

                    foreach ($cookie as $pos => $val) {

                        $val = explode('=', $val, 2);

                        $tag = trim($val[0]);

                        $val = isset($val[1]) ? trim($val[1]) : '';

                        if ($pos === 0) {

                            $cookieName = $tag;

                            // if present, we have strip leading and trailing " chars from $val

                            if (preg_match('/^"(.*)"$/', $val, $matches)) {

                                $val = $matches[1];

                            }

                            $httpResponse['cookies'][$cookieName] = array('value' => urldecode($val));

                        } else {

                            $httpResponse['cookies'][$cookieName][$tag] = $val;

                        }

                    }

                } else {

                    /// @todo some other headers (the ones that allow a CSV list of values) do allow many values to be

                    ///       passed using multiple header lines.

                    ///       We should add content to $xmlrpc->_xh['headers'][$headerName] instead of replacing it for those...

                    $httpResponse['headers'][$headerName] = trim($arr[1]);

                }

            } elseif (isset($headerName)) {

                /// @todo improve this: 1. check that the line starts with a space or tab; 2. according to

                ///       https://www.rfc-editor.org/rfc/rfc7230#section-3.2.4, we should flat out refuse these messages

                $httpResponse['headers'][$headerName] .= ' ' . trim($line);

            }

        }

        $data = substr($data, $bd);

        if ($debug && count($httpResponse['headers'])) {

            $msg = '';

            foreach ($httpResponse['headers'] as $header => $value) {

                $msg .= "HEADER: $header: $value\n";

            }

            foreach ($httpResponse['cookies'] as $header => $value) {

                $msg .= "COOKIE: $header={$value['value']}\n";

            }

            $this->getLogger()->debug($msg);

        }

        // if CURL was used for the call, http headers have been processed, and dechunking + reinflating have been carried out

        if (!$headersProcessed) {

            // Decode chunked encoding sent by http 1.1 servers

            if (isset($httpResponse['headers']['transfer-encoding']) && $httpResponse['headers']['transfer-encoding'] == 'chunked') {

                if (!$data = static::decodeChunked($data)) {

                    $this->getLogger()->error('XML-RPC: ' . __METHOD__ . ': errors occurred when trying to rebuild the chunked data received from server');

                    throw new HttpException(PhpXmlRpc::$xmlrpcstr['dechunk_fail'], PhpXmlRpc::$xmlrpcerr['dechunk_fail'], null, $httpResponse['status_code']);

                }

            }

            // Decode gzip-compressed stuff

            // code shamelessly inspired from nusoap library by Dietrich Ayala

            if (isset($httpResponse['headers']['content-encoding'])) {

                $httpResponse['headers']['content-encoding'] = str_replace('x-', '', $httpResponse['headers']['content-encoding']);

                if ($httpResponse['headers']['content-encoding'] == 'deflate' || $httpResponse['headers']['content-encoding'] == 'gzip') {

                    // if decoding works, use it. else assume data wasn't gzencoded

                    if (function_exists('gzinflate')) {

                        if ($httpResponse['headers']['content-encoding'] == 'deflate' && $degzdata = @gzuncompress($data)) {

                            $data = $degzdata;

                            if ($debug) {

                                $this->getLogger()->debug("---INFLATED RESPONSE---[" . strlen($data) . " chars]---\n$data\n---END---");

                            }

                        } elseif ($httpResponse['headers']['content-encoding'] == 'gzip' && $degzdata = @gzinflate(substr($data, 10))) {

                            $data = $degzdata;

                            if ($debug) {

                                $this->getLogger()->debug("---INFLATED RESPONSE---[" . strlen($data) . " chars]---\n$data\n---END---");

                            }

                        } else {

                            $this->getLogger()->error('XML-RPC: ' . __METHOD__ . ': errors occurred when trying to decode the deflated data received from server');

                            throw new HttpException(PhpXmlRpc::$xmlrpcstr['decompress_fail'], PhpXmlRpc::$xmlrpcerr['decompress_fail'], null, $httpResponse['status_code']);

                        }

                    } else {

                        $this->getLogger()->error('XML-RPC: ' . __METHOD__ . ': the server sent deflated data. Your php install must have the Zlib extension compiled in to support this.');

                        throw new HttpException(PhpXmlRpc::$xmlrpcstr['cannot_decompress'], PhpXmlRpc::$xmlrpcerr['cannot_decompress'], null, $httpResponse['status_code']);

                    }

                }

            }

        } // end of 'if needed, de-chunk, re-inflate response'

        return $httpResponse;

    }

    /**

     * Parses one of the http headers which can have a list of values with quality param.

     * @see https://www.rfc-editor.org/rfc/rfc7231#section-5.3.1

     *

     * @param string $header

     * @return string[]

     */

    public function parseAcceptHeader($header)

    {

        $accepted = array();

        foreach(explode(',', $header) as $c) {

            if (preg_match('/^([^;]+); *q=([0-9.]+)/', $c, $matches)) {

                $c = $matches[1];

                $w = $matches[2];

            } else {

                $c = preg_replace('/;.*/', '', $c);

                $w = 1;

            }

            $accepted[(trim($c))] = $w;

        }

        arsort($accepted);

        return array_keys($accepted);

    }

}