includes/HttpFunctions.php

   1 <?php
   2 /**
   3  * @defgroup HTTP HTTP
   4  */
   5
   6 /**
   7  * Various HTTP related functions
   8  * @ingroup HTTP
   9  */
  10 class Http {
  11         static $httpEngine = false;
  12
  13         /**
  14          * Perform an HTTP request
  15          *
  16          * @param $method String: HTTP method. Usually GET/POST
  17          * @param $url String: full URL to act on
  18          * @param $options Array: options to pass to MWHttpRequest object.
  19          *      Possible keys for the array:
  20          *    - timeout             Timeout length in seconds
  21          *    - postData            An array of key-value pairs or a url-encoded form data
  22          *    - proxy               The proxy to use.
  23          *                          Will use $wgHTTPProxy (if set) otherwise.
  24          *    - noProxy             Override $wgHTTPProxy (if set) and don't use any proxy at all.
  25          *    - sslVerifyHost       (curl only) Verify hostname against certificate
  26          *    - sslVerifyCert       (curl only) Verify SSL certificate
  27          *    - caInfo              (curl only) Provide CA information
  28          *    - maxRedirects        Maximum number of redirects to follow (defaults to 5)
  29          *    - followRedirects     Whether to follow redirects (defaults to false).
  30          *                                  Note: this should only be used when the target URL is trusted,
  31          *                                  to avoid attacks on intranet services accessible by HTTP.
  32          * @return Mixed: (bool)false on failure or a string on success
  33          */
  34         public static function request( $method, $url, $options = array() ) {
  35                 $url = wfExpandUrl( $url );
  36                 wfDebug( "HTTP: $method: $url\n" );
  37                 $options['method'] = strtoupper( $method );
  38
  39                 if ( !isset( $options['timeout'] ) ) {
  40                         $options['timeout'] = 'default';
  41                 }
  42
  43                 $req = MWHttpRequest::factory( $url, $options );
  44                 $status = $req->execute();
  45
  46                 if ( $status->isOK() ) {
  47                         return $req->getContent();
  48                 } else {
  49                         return false;
  50                 }
  51         }
  52
  53         /**
  54          * Simple wrapper for Http::request( 'GET' )
  55          * @see Http::request()
  56          *
  57          * @return string
  58          */
  59         public static function get( $url, $timeout = 'default', $options = array() ) {
  60                 $options['timeout'] = $timeout;
  61                 return Http::request( 'GET', $url, $options );
  62         }
  63
  64         /**
  65          * Simple wrapper for Http::request( 'POST' )
  66          * @see Http::request()
  67          *
  68          * @return string
  69          */
  70         public static function post( $url, $options = array() ) {
  71                 return Http::request( 'POST', $url, $options );
  72         }
  73
  74         /**
  75          * Check if the URL can be served by localhost
  76          *
  77          * @param $url String: full url to check
  78          * @return Boolean
  79          */
  80         public static function isLocalURL( $url ) {
  81                 global $wgCommandLineMode, $wgConf;
  82
  83                 if ( $wgCommandLineMode ) {
  84                         return false;
  85                 }
  86
  87                 // Extract host part
  88                 $matches = array();
  89                 if ( preg_match( '!^http://([\w.-]+)[/:].*$!', $url, $matches ) ) {
  90                         $host = $matches[1];
  91                         // Split up dotwise
  92                         $domainParts = explode( '.', $host );
  93                         // Check if this domain or any superdomain is listed in $wgConf as a local virtual host
  94                         $domainParts = array_reverse( $domainParts );
  95
  96                         $domain = '';
  97                         for ( $i = 0; $i < count( $domainParts ); $i++ ) {
  98                                 $domainPart = $domainParts[$i];
  99                                 if ( $i == 0 ) {
 100                                         $domain = $domainPart;
 101                                 } else {
 102                                         $domain = $domainPart . '.' . $domain;
 103                                 }
 104
 105                                 if ( $wgConf->isLocalVHost( $domain ) ) {
 106                                         return true;
 107                                 }
 108                         }
 109                 }
 110
 111                 return false;
 112         }
 113
 114         /**
 115          * A standard user-agent we can use for external requests.
 116          * @return String
 117          */
 118         public static function userAgent() {
 119                 global $wgVersion;
 120                 return "MediaWiki/$wgVersion";
 121         }
 122
 123         /**
 124          * Checks that the given URI is a valid one. Hardcoding the
 125          * protocols, because we only want protocols that both cURL
 126          * and php support.
 127          *
 128          * @fixme this is wildly inaccurate and fails to actually check most stuff
 129          * @fixme do we actually intend to have FTP support here? Does it work consistently?
 130          *
 131          * @param $uri Mixed: URI to check for validity
 132          * @returns Boolean
 133          */
 134         public static function isValidURI( $uri ) {
 135                 return preg_match(
 136                         '/^(f|ht)tps?:\/\/[^\/\s]\S*$/D',
 137                         $uri
 138                 );
 139         }
 140 }
 141
 142 /**
 143  * This wrapper class will call out to curl (if available) or fallback
 144  * to regular PHP if necessary for handling internal HTTP requests.
 145  *
 146  * Renamed from HttpRequest to MWHttpRequest to avoid conflict with
 147  * PHP's HTTP extension.
 148  */
 149 class MWHttpRequest {
 150         const SUPPORTS_FILE_POSTS = false;
 151
 152         protected $content;
 153         protected $timeout = 'default';
 154         protected $headersOnly = null;
 155         protected $postData = null;
 156         protected $proxy = null;
 157         protected $noProxy = false;
 158         protected $sslVerifyHost = true;
 159         protected $sslVerifyCert = true;
 160         protected $caInfo = null;
 161         protected $method = "GET";
 162         protected $reqHeaders = array();
 163         protected $url;
 164         protected $parsedUrl;
 165         protected $callback;
 166         protected $maxRedirects = 5;
 167         protected $followRedirects = false;
 168
 169         /**
 170          * @var  CookieJar
 171          */
 172         protected $cookieJar;
 173
 174         protected $headerList = array();
 175         protected $respVersion = "0.9";
 176         protected $respStatus = "200 Ok";
 177         protected $respHeaders = array();
 178
 179         public $status;
 180
 181         /**
 182          * @param $url String: url to use
 183          * @param $options Array: (optional) extra params to pass (see Http::request())
 184          */
 185         function __construct( $url, $options = array() ) {
 186                 global $wgHTTPTimeout;
 187
 188                 $this->url = $url;
 189                 $this->parsedUrl = parse_url( $url );
 190
 191                 if ( !Http::isValidURI( $this->url ) ) {
 192                         $this->status = Status::newFatal( 'http-invalid-url' );
 193                 } else {
 194                         $this->status = Status::newGood( 100 ); // continue
 195                 }
 196
 197                 if ( isset( $options['timeout'] ) && $options['timeout'] != 'default' ) {
 198                         $this->timeout = $options['timeout'];
 199                 } else {
 200                         $this->timeout = $wgHTTPTimeout;
 201                 }
 202
 203                 $members = array( "postData", "proxy", "noProxy", "sslVerifyHost", "caInfo",
 204                                   "method", "followRedirects", "maxRedirects", "sslVerifyCert", "callback" );
 205
 206                 foreach ( $members as $o ) {
 207                         if ( isset( $options[$o] ) ) {
 208                                 $this->$o = $options[$o];
 209                         }
 210                 }
 211         }
 212
 213         /**
 214          * Generate a new request object
 215          * @param $url String: url to use
 216          * @param $options Array: (optional) extra params to pass (see Http::request())
 217          * @see MWHttpRequest::__construct
 218          */
 219         public static function factory( $url, $options = null ) {
 220                 if ( !Http::$httpEngine ) {
 221                         Http::$httpEngine = function_exists( 'curl_init' ) ? 'curl' : 'php';
 222                 } elseif ( Http::$httpEngine == 'curl' && !function_exists( 'curl_init' ) ) {
 223                         throw new MWException( __METHOD__ . ': curl (http://php.net/curl) is not installed, but' .
 224                                                                    ' Http::$httpEngine is set to "curl"' );
 225                 }
 226
 227                 switch( Http::$httpEngine ) {
 228                         case 'curl':
 229                                 return new CurlHttpRequest( $url, $options );
 230                         case 'php':
 231                                 if ( !wfIniGetBool( 'allow_url_fopen' ) ) {
 232                                         throw new MWException( __METHOD__ . ': allow_url_fopen needs to be enabled for pure PHP' .
 233                                                 ' http requests to work. If possible, curl should be used instead. See http://php.net/curl.' );
 234                                 }
 235                                 return new PhpHttpRequest( $url, $options );
 236                         default:
 237                                 throw new MWException( __METHOD__ . ': The setting of Http::$httpEngine is not valid.' );
 238                 }
 239         }
 240
 241         /**
 242          * Get the body, or content, of the response to the request
 243          *
 244          * @return String
 245          */
 246         public function getContent() {
 247                 return $this->content;
 248         }
 249
 250         /**
 251          * Set the parameters of the request
 252
 253          * @param $args Array
 254          * @todo overload the args param
 255          */
 256         public function setData( $args ) {
 257                 $this->postData = $args;
 258         }
 259
 260         /**
 261          * Take care of setting up the proxy
 262          * (override in subclass)
 263          *
 264          * @return String
 265          */
 266         public function proxySetup() {
 267                 global $wgHTTPProxy;
 268
 269                 if ( $this->proxy ) {
 270                         return;
 271                 }
 272
 273                 if ( Http::isLocalURL( $this->url ) ) {
 274                         $this->proxy = 'http://localhost:80/';
 275                 } elseif ( $wgHTTPProxy ) {
 276                         $this->proxy = $wgHTTPProxy ;
 277                 } elseif ( getenv( "http_proxy" ) ) {
 278                         $this->proxy = getenv( "http_proxy" );
 279                 }
 280         }
 281
 282         /**
 283          * Set the refererer header
 284          */
 285         public function setReferer( $url ) {
 286                 $this->setHeader( 'Referer', $url );
 287         }
 288
 289         /**
 290          * Set the user agent
 291          */
 292         public function setUserAgent( $UA ) {
 293                 $this->setHeader( 'User-Agent', $UA );
 294         }
 295
 296         /**
 297          * Set an arbitrary header
 298          */
 299         public function setHeader( $name, $value ) {
 300                 // I feel like I should normalize the case here...
 301                 $this->reqHeaders[$name] = $value;
 302         }
 303
 304         /**
 305          * Get an array of the headers
 306          */
 307         public function getHeaderList() {
 308                 $list = array();
 309
 310                 if ( $this->cookieJar ) {
 311                         $this->reqHeaders['Cookie'] =
 312                                 $this->cookieJar->serializeToHttpRequest(
 313                                         $this->parsedUrl['path'],
 314                                         $this->parsedUrl['host']
 315                                 );
 316                 }
 317
 318                 foreach ( $this->reqHeaders as $name => $value ) {
 319                         $list[] = "$name: $value";
 320                 }
 321
 322                 return $list;
 323         }
 324
 325         /**
 326          * Set a read callback to accept data read from the HTTP request.
 327          * By default, data is appended to an internal buffer which can be
 328          * retrieved through $req->getContent().
 329          *
 330          * To handle data as it comes in -- especially for large files that
 331          * would not fit in memory -- you can instead set your own callback,
 332          * in the form function($resource, $buffer) where the first parameter
 333          * is the low-level resource being read (implementation specific),
 334          * and the second parameter is the data buffer.
 335          *
 336          * You MUST return the number of bytes handled in the buffer; if fewer
 337          * bytes are reported handled than were passed to you, the HTTP fetch
 338          * will be aborted.
 339          *
 340          * @param $callback Callback
 341          */
 342         public function setCallback( $callback ) {
 343                 if ( !is_callable( $callback ) ) {
 344                         throw new MWException( 'Invalid MwHttpRequest callback' );
 345                 }
 346                 $this->callback = $callback;
 347         }
 348
 349         /**
 350          * A generic callback to read the body of the response from a remote
 351          * server.
 352          *
 353          * @param $fh handle
 354          * @param $content String
 355          */
 356         public function read( $fh, $content ) {
 357                 $this->content .= $content;
 358                 return strlen( $content );
 359         }
 360
 361         /**
 362          * Take care of whatever is necessary to perform the URI request.
 363          *
 364          * @return Status
 365          */
 366         public function execute() {
 367                 global $wgTitle;
 368
 369                 $this->content = "";
 370
 371                 if ( strtoupper( $this->method ) == "HEAD" ) {
 372                         $this->headersOnly = true;
 373                 }
 374
 375                 if ( is_object( $wgTitle ) && !isset( $this->reqHeaders['Referer'] ) ) {
 376                         $this->setReferer( $wgTitle->getFullURL() );
 377                 }
 378
 379                 if ( !$this->noProxy ) {
 380                         $this->proxySetup();
 381                 }
 382
 383                 if ( !$this->callback ) {
 384                         $this->setCallback( array( $this, 'read' ) );
 385                 }
 386
 387                 if ( !isset( $this->reqHeaders['User-Agent'] ) ) {
 388                         $this->setUserAgent( Http::userAgent() );
 389                 }
 390         }
 391
 392         /**
 393          * Parses the headers, including the HTTP status code and any
 394          * Set-Cookie headers.  This function expectes the headers to be
 395          * found in an array in the member variable headerList.
 396          *
 397          * @return nothing
 398          */
 399         protected function parseHeader() {
 400                 $lastname = "";
 401
 402                 foreach ( $this->headerList as $header ) {
 403                         if ( preg_match( "#^HTTP/([0-9.]+) (.*)#", $header, $match ) ) {
 404                                 $this->respVersion = $match[1];
 405                                 $this->respStatus = $match[2];
 406                         } elseif ( preg_match( "#^[ \t]#", $header ) ) {
 407                                 $last = count( $this->respHeaders[$lastname] ) - 1;
 408                                 $this->respHeaders[$lastname][$last] .= "\r\n$header";
 409                         } elseif ( preg_match( "#^([^:]*):[\t ]*(.*)#", $header, $match ) ) {
 410                                 $this->respHeaders[strtolower( $match[1] )][] = $match[2];
 411                                 $lastname = strtolower( $match[1] );
 412                         }
 413                 }
 414
 415                 $this->parseCookies();
 416         }
 417
 418         /**
 419          * Sets HTTPRequest status member to a fatal value with the error
 420          * message if the returned integer value of the status code was
 421          * not successful (< 300) or a redirect (>=300 and < 400).  (see
 422          * RFC2616, section 10,
 423          * http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html for a
 424          * list of status codes.)
 425          *
 426          * @return nothing
 427          */
 428         protected function setStatus() {
 429                 if ( !$this->respHeaders ) {
 430                         $this->parseHeader();
 431                 }
 432
 433                 if ( (int)$this->respStatus > 399 ) {
 434                         list( $code, $message ) = explode( " ", $this->respStatus, 2 );
 435                         $this->status->fatal( "http-bad-status", $code, $message );
 436                 }
 437         }
 438
 439         /**
 440          * Get the integer value of the HTTP status code (e.g. 200 for "200 Ok")
 441          * (see RFC2616, section 10, http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html
 442          * for a list of status codes.)
 443          *
 444          * @return Integer
 445          */
 446         public function getStatus() {
 447                 if ( !$this->respHeaders ) {
 448                         $this->parseHeader();
 449                 }
 450
 451                 return (int)$this->respStatus;
 452         }
 453
 454
 455         /**
 456          * Returns true if the last status code was a redirect.
 457          *
 458          * @return Boolean
 459          */
 460         public function isRedirect() {
 461                 if ( !$this->respHeaders ) {
 462                         $this->parseHeader();
 463                 }
 464
 465                 $status = (int)$this->respStatus;
 466
 467                 if ( $status >= 300 && $status <= 303 ) {
 468                         return true;
 469                 }
 470
 471                 return false;
 472         }
 473
 474         /**
 475          * Returns an associative array of response headers after the
 476          * request has been executed.  Because some headers
 477          * (e.g. Set-Cookie) can appear more than once the, each value of
 478          * the associative array is an array of the values given.
 479          *
 480          * @return Array
 481          */
 482         public function getResponseHeaders() {
 483                 if ( !$this->respHeaders ) {
 484                         $this->parseHeader();
 485                 }
 486
 487                 return $this->respHeaders;
 488         }
 489
 490         /**
 491          * Returns the value of the given response header.
 492          *
 493          * @param $header String
 494          * @return String
 495          */
 496         public function getResponseHeader( $header ) {
 497                 if ( !$this->respHeaders ) {
 498                         $this->parseHeader();
 499                 }
 500
 501                 if ( isset( $this->respHeaders[strtolower ( $header ) ] ) ) {
 502                         $v = $this->respHeaders[strtolower ( $header ) ];
 503                         return $v[count( $v ) - 1];
 504                 }
 505
 506                 return null;
 507         }
 508
 509         /**
 510          * Tells the MWHttpRequest object to use this pre-loaded CookieJar.
 511          *
 512          * @param $jar CookieJar
 513          */
 514         public function setCookieJar( $jar ) {
 515                 $this->cookieJar = $jar;
 516         }
 517
 518         /**
 519          * Returns the cookie jar in use.
 520          *
 521          * @returns CookieJar
 522          */
 523         public function getCookieJar() {
 524                 if ( !$this->respHeaders ) {
 525                         $this->parseHeader();
 526                 }
 527
 528                 return $this->cookieJar;
 529         }
 530
 531         /**
 532          * Sets a cookie.  Used before a request to set up any individual
 533          * cookies.      Used internally after a request to parse the
 534          * Set-Cookie headers.
 535          * @see Cookie::set
 536          */
 537         public function setCookie( $name, $value = null, $attr = null ) {
 538                 if ( !$this->cookieJar ) {
 539                         $this->cookieJar = new CookieJar;
 540                 }
 541
 542                 $this->cookieJar->setCookie( $name, $value, $attr );
 543         }
 544
 545         /**
 546          * Parse the cookies in the response headers and store them in the cookie jar.
 547          */
 548         protected function parseCookies() {
 549                 if ( !$this->cookieJar ) {
 550                         $this->cookieJar = new CookieJar;
 551                 }
 552
 553                 if ( isset( $this->respHeaders['set-cookie'] ) ) {
 554                         $url = parse_url( $this->getFinalUrl() );
 555                         foreach ( $this->respHeaders['set-cookie'] as $cookie ) {
 556                                 $this->cookieJar->parseCookieResponseHeader( $cookie, $url['host'] );
 557                         }
 558                 }
 559         }
 560
 561         /**
 562          * Returns the final URL after all redirections.
 563          *
 564          * @return String
 565          */
 566         public function getFinalUrl() {
 567                 $location = $this->getResponseHeader( "Location" );
 568
 569                 if ( $location ) {
 570                         return $location;
 571                 }
 572
 573                 return $this->url;
 574         }
 575
 576         /**
 577          * Returns true if the backend can follow redirects. Overridden by the
 578          * child classes.
 579          */
 580         public function canFollowRedirects() {
 581                 return true;
 582         }
 583 }
 584
 585 /**
 586  * MWHttpRequest implemented using internal curl compiled into PHP
 587  */
 588 class CurlHttpRequest extends MWHttpRequest {
 589         const SUPPORTS_FILE_POSTS = true;
 590
 591         static $curlMessageMap = array(
 592                 6 => 'http-host-unreachable',
 593                 28 => 'http-timed-out'
 594         );
 595
 596         protected $curlOptions = array();
 597         protected $headerText = "";
 598
 599         protected function readHeader( $fh, $content ) {
 600                 $this->headerText .= $content;
 601                 return strlen( $content );
 602         }
 603
 604         public function execute() {
 605                 parent::execute();
 606
 607                 if ( !$this->status->isOK() ) {
 608                         return $this->status;
 609                 }
 610
 611                 $this->curlOptions[CURLOPT_PROXY] = $this->proxy;
 612                 $this->curlOptions[CURLOPT_TIMEOUT] = $this->timeout;
 613                 $this->curlOptions[CURLOPT_HTTP_VERSION] = CURL_HTTP_VERSION_1_0;
 614                 $this->curlOptions[CURLOPT_WRITEFUNCTION] = $this->callback;
 615                 $this->curlOptions[CURLOPT_HEADERFUNCTION] = array( $this, "readHeader" );
 616                 $this->curlOptions[CURLOPT_MAXREDIRS] = $this->maxRedirects;
 617                 $this->curlOptions[CURLOPT_ENCODING] = ""; # Enable compression
 618
 619                 /* not sure these two are actually necessary */
 620                 if ( isset( $this->reqHeaders['Referer'] ) ) {
 621                         $this->curlOptions[CURLOPT_REFERER] = $this->reqHeaders['Referer'];
 622                 }
 623                 $this->curlOptions[CURLOPT_USERAGENT] = $this->reqHeaders['User-Agent'];
 624
 625                 if ( isset( $this->sslVerifyHost ) ) {
 626                         $this->curlOptions[CURLOPT_SSL_VERIFYHOST] = $this->sslVerifyHost;
 627                 }
 628
 629                 if ( isset( $this->sslVerifyCert ) ) {
 630                         $this->curlOptions[CURLOPT_SSL_VERIFYPEER] = $this->sslVerifyCert;
 631                 }
 632
 633                 if ( $this->caInfo ) {
 634                         $this->curlOptions[CURLOPT_CAINFO] = $this->caInfo;
 635                 }
 636
 637                 if ( $this->headersOnly ) {
 638                         $this->curlOptions[CURLOPT_NOBODY] = true;
 639                         $this->curlOptions[CURLOPT_HEADER] = true;
 640                 } elseif ( $this->method == 'POST' ) {
 641                         $this->curlOptions[CURLOPT_POST] = true;
 642                         $this->curlOptions[CURLOPT_POSTFIELDS] = $this->postData;
 643                         // Suppress 'Expect: 100-continue' header, as some servers
 644                         // will reject it with a 417 and Curl won't auto retry
 645                         // with HTTP 1.0 fallback
 646                         $this->reqHeaders['Expect'] = '';
 647                 } else {
 648                         $this->curlOptions[CURLOPT_CUSTOMREQUEST] = $this->method;
 649                 }
 650
 651                 $this->curlOptions[CURLOPT_HTTPHEADER] = $this->getHeaderList();
 652
 653                 $curlHandle = curl_init( $this->url );
 654
 655                 if ( !curl_setopt_array( $curlHandle, $this->curlOptions ) ) {
 656                         throw new MWException( "Error setting curl options." );
 657                 }
 658
 659                 if ( $this->followRedirects && $this->canFollowRedirects() ) {
 660                         wfSuppressWarnings();
 661                         if ( ! curl_setopt( $curlHandle, CURLOPT_FOLLOWLOCATION, true ) ) {
 662                                 wfDebug( __METHOD__ . ": Couldn't set CURLOPT_FOLLOWLOCATION. " .
 663                                         "Probably safe_mode or open_basedir is set.\n" );
 664                                 // Continue the processing. If it were in curl_setopt_array,
 665                                 // processing would have halted on its entry
 666                         }
 667                         wfRestoreWarnings();
 668                 }
 669
 670                 if ( false === curl_exec( $curlHandle ) ) {
 671                         $code = curl_error( $curlHandle );
 672
 673                         if ( isset( self::$curlMessageMap[$code] ) ) {
 674                                 $this->status->fatal( self::$curlMessageMap[$code] );
 675                         } else {
 676                                 $this->status->fatal( 'http-curl-error', curl_error( $curlHandle ) );
 677                         }
 678                 } else {
 679                         $this->headerList = explode( "\r\n", $this->headerText );
 680                 }
 681
 682                 curl_close( $curlHandle );
 683
 684                 $this->parseHeader();
 685                 $this->setStatus();
 686
 687                 return $this->status;
 688         }
 689
 690         public function canFollowRedirects() {
 691                 if ( strval( ini_get( 'open_basedir' ) ) !== '' || wfIniGetBool( 'safe_mode' ) ) {
 692                         wfDebug( "Cannot follow redirects in safe mode\n" );
 693                         return false;
 694                 }
 695
 696                 if ( !defined( 'CURLOPT_REDIR_PROTOCOLS' ) ) {
 697                         wfDebug( "Cannot follow redirects with libcurl < 7.19.4 due to CVE-2009-0037\n" );
 698                         return false;
 699                 }
 700
 701                 return true;
 702         }
 703 }
 704
 705 class PhpHttpRequest extends MWHttpRequest {
 706         protected function urlToTcp( $url ) {
 707                 $parsedUrl = parse_url( $url );
 708
 709                 return 'tcp://' . $parsedUrl['host'] . ':' . $parsedUrl['port'];
 710         }
 711
 712         public function execute() {
 713                 parent::execute();
 714
 715                 if ( is_array( $this->postData ) ) {
 716                         $this->postData = wfArrayToCGI( $this->postData );
 717                 }
 718
 719                 if ( $this->parsedUrl['scheme'] != 'http' &&
 720                          $this->parsedUrl['scheme'] != 'ftp' &&
 721                          $this->parsedUrl['scheme'] != 'https' ) {
 722                         $this->status->fatal( 'http-invalid-scheme', $this->parsedUrl['scheme'] );
 723                 }
 724
 725                 $this->reqHeaders['Accept'] = "*/*";
 726                 if ( $this->method == 'POST' ) {
 727                         // Required for HTTP 1.0 POSTs
 728                         $this->reqHeaders['Content-Length'] = strlen( $this->postData );
 729                         $this->reqHeaders['Content-type'] = "application/x-www-form-urlencoded";
 730                 }
 731
 732                 $options = array();
 733                 if ( $this->proxy && !$this->noProxy ) {
 734                         $options['proxy'] = $this->urlToTCP( $this->proxy );
 735                         $options['request_fulluri'] = true;
 736                 }
 737
 738                 if ( !$this->followRedirects ) {
 739                         $options['max_redirects'] = 0;
 740                 } else {
 741                         $options['max_redirects'] = $this->maxRedirects;
 742                 }
 743
 744                 $options['method'] = $this->method;
 745                 $options['header'] = implode( "\r\n", $this->getHeaderList() );
 746                 // Note that at some future point we may want to support
 747                 // HTTP/1.1, but we'd have to write support for chunking
 748                 // in version of PHP < 5.3.1
 749                 $options['protocol_version'] = "1.0";
 750
 751                 // This is how we tell PHP we want to deal with 404s (for example) ourselves.
 752                 // Only works on 5.2.10+
 753                 $options['ignore_errors'] = true;
 754
 755                 if ( $this->postData ) {
 756                         $options['content'] = $this->postData;
 757                 }
 758
 759                 $options['timeout'] = $this->timeout;
 760
 761                 $context = stream_context_create( array( 'http' => $options ) );
 762
 763                 $this->headerList = array();
 764                 $reqCount = 0;
 765                 $url = $this->url;
 766
 767                 $result = array();
 768
 769                 do {
 770                         $reqCount++;
 771                         wfSuppressWarnings();
 772                         $fh = fopen( $url, "r", false, $context );
 773                         wfRestoreWarnings();
 774
 775                         if ( !$fh ) {
 776                                 break;
 777                         }
 778
 779                         $result = stream_get_meta_data( $fh );
 780                         $this->headerList = $result['wrapper_data'];
 781                         $this->parseHeader();
 782
 783                         if ( !$this->followRedirects ) {
 784                                 break;
 785                         }
 786
 787                         # Handle manual redirection
 788                         if ( !$this->isRedirect() || $reqCount > $this->maxRedirects ) {
 789                                 break;
 790                         }
 791                         # Check security of URL
 792                         $url = $this->getResponseHeader( "Location" );
 793
 794                         if ( substr( $url, 0, 7 ) !== 'http://' ) {
 795                                 wfDebug( __METHOD__ . ": insecure redirection\n" );
 796                                 break;
 797                         }
 798                 } while ( true );
 799
 800                 $this->setStatus();
 801
 802                 if ( $fh === false ) {
 803                         $this->status->fatal( 'http-request-error' );
 804                         return $this->status;
 805                 }
 806
 807                 if ( $result['timed_out'] ) {
 808                         $this->status->fatal( 'http-timed-out', $this->url );
 809                         return $this->status;
 810                 }
 811
 812                 // If everything went OK, or we recieved some error code
 813                 // get the response body content.
 814                 if ( $this->status->isOK()
 815                                 || (int)$this->respStatus >= 300) {
 816                         while ( !feof( $fh ) ) {
 817                                 $buf = fread( $fh, 8192 );
 818
 819                                 if ( $buf === false ) {
 820                                         $this->status->fatal( 'http-read-error' );
 821                                         break;
 822                                 }
 823
 824                                 if ( strlen( $buf ) ) {
 825                                         call_user_func( $this->callback, $fh, $buf );
 826                                 }
 827                         }
 828                 }
 829                 fclose( $fh );
 830
 831                 return $this->status;
 832         }
 833 }