includes/WebRequest.php

   1 <?php
   2 /**
   3  * Deal with importing all those nasty globals and things
   4  *
   5  * Copyright © 2003 Brion Vibber <brion@pobox.com>
   6  * https://www.mediawiki.org/
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License along
  19  * with this program; if not, write to the Free Software Foundation, Inc.,
  20  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  21  * http://www.gnu.org/copyleft/gpl.html
  22  *
  23  * @file
  24  */
  25
  26 use MediaWiki\Session\Session;
  27 use MediaWiki\Session\SessionId;
  28 use MediaWiki\Session\SessionManager;
  29
  30 /**
  31  * The WebRequest class encapsulates getting at data passed in the
  32  * URL or via a POSTed form stripping illegal input characters and
  33  * normalizing Unicode sequences.
  34  *
  35  * @ingroup HTTP
  36  */
  37 class WebRequest {
  38         protected $data, $headers = [];
  39
  40         /**
  41          * Flag to make WebRequest::getHeader return an array of values.
  42          * @since 1.26
  43          */
  44         const GETHEADER_LIST = 1;
  45
  46         /**
  47          * The unique request ID.
  48          * @var string
  49          */
  50         private static $reqId;
  51
  52         /**
  53          * Lazy-init response object
  54          * @var WebResponse
  55          */
  56         private $response;
  57
  58         /**
  59          * Cached client IP address
  60          * @var string
  61          */
  62         private $ip;
  63
  64         /**
  65          * The timestamp of the start of the request, with microsecond precision.
  66          * @var float
  67          */
  68         protected $requestTime;
  69
  70         /**
  71          * Cached URL protocol
  72          * @var string
  73          */
  74         protected $protocol;
  75
  76         /**
  77          * @var SessionId|null Session ID to use for this
  78          *  request. We can't save the session directly due to reference cycles not
  79          *  working too well (slow GC in Zend and never collected in HHVM).
  80          */
  81         protected $sessionId = null;
  82
  83         /** @var bool Whether this HTTP request is "safe" (even if it is an HTTP post) */
  84         protected $markedAsSafe = false;
  85
  86         /**
  87          * @codeCoverageIgnore
  88          */
  89         public function __construct() {
  90                 $this->requestTime = isset( $_SERVER['REQUEST_TIME_FLOAT'] )
  91                         ? $_SERVER['REQUEST_TIME_FLOAT'] : microtime( true );
  92
  93                 // POST overrides GET data
  94                 // We don't use $_REQUEST here to avoid interference from cookies...
  95                 $this->data = $_POST + $_GET;
  96         }
  97
  98         /**
  99          * Extract relevant query arguments from the http request uri's path
 100          * to be merged with the normal php provided query arguments.
 101          * Tries to use the REQUEST_URI data if available and parses it
 102          * according to the wiki's configuration looking for any known pattern.
 103          *
 104          * If the REQUEST_URI is not provided we'll fall back on the PATH_INFO
 105          * provided by the server if any and use that to set a 'title' parameter.
 106          *
 107          * @param string $want If this is not 'all', then the function
 108          * will return an empty array if it determines that the URL is
 109          * inside a rewrite path.
 110          *
 111          * @return array Any query arguments found in path matches.
 112          */
 113         public static function getPathInfo( $want = 'all' ) {
 114                 global $wgUsePathInfo;
 115                 // PATH_INFO is mangled due to http://bugs.php.net/bug.php?id=31892
 116                 // And also by Apache 2.x, double slashes are converted to single slashes.
 117                 // So we will use REQUEST_URI if possible.
 118                 $matches = [];
 119                 if ( !empty( $_SERVER['REQUEST_URI'] ) ) {
 120                         // Slurp out the path portion to examine...
 121                         $url = $_SERVER['REQUEST_URI'];
 122                         if ( !preg_match( '!^https?://!', $url ) ) {
 123                                 $url = 'http://unused' . $url;
 124                         }
 125                         MediaWiki\suppressWarnings();
 126                         $a = parse_url( $url );
 127                         MediaWiki\restoreWarnings();
 128                         if ( $a ) {
 129                                 $path = isset( $a['path'] ) ? $a['path'] : '';
 130
 131                                 global $wgScript;
 132                                 if ( $path == $wgScript && $want !== 'all' ) {
 133                                         // Script inside a rewrite path?
 134                                         // Abort to keep from breaking...
 135                                         return $matches;
 136                                 }
 137
 138                                 $router = new PathRouter;
 139
 140                                 // Raw PATH_INFO style
 141                                 $router->add( "$wgScript/$1" );
 142
 143                                 if ( isset( $_SERVER['SCRIPT_NAME'] )
 144                                         && preg_match( '/\.php5?/', $_SERVER['SCRIPT_NAME'] )
 145                                 ) {
 146                                         # Check for SCRIPT_NAME, we handle index.php explicitly
 147                                         # But we do have some other .php files such as img_auth.php
 148                                         # Don't let root article paths clober the parsing for them
 149                                         $router->add( $_SERVER['SCRIPT_NAME'] . "/$1" );
 150                                 }
 151
 152                                 global $wgArticlePath;
 153                                 if ( $wgArticlePath ) {
 154                                         $router->add( $wgArticlePath );
 155                                 }
 156
 157                                 global $wgActionPaths;
 158                                 if ( $wgActionPaths ) {
 159                                         $router->add( $wgActionPaths, [ 'action' => '$key' ] );
 160                                 }
 161
 162                                 global $wgVariantArticlePath, $wgContLang;
 163                                 if ( $wgVariantArticlePath ) {
 164                                         $router->add( $wgVariantArticlePath,
 165                                                 [ 'variant' => '$2' ],
 166                                                 [ '$2' => $wgContLang->getVariants() ]
 167                                         );
 168                                 }
 169
 170                                 Hooks::run( 'WebRequestPathInfoRouter', [ $router ] );
 171
 172                                 $matches = $router->parse( $path );
 173                         }
 174                 } elseif ( $wgUsePathInfo ) {
 175                         if ( isset( $_SERVER['ORIG_PATH_INFO'] ) && $_SERVER['ORIG_PATH_INFO'] != '' ) {
 176                                 // Mangled PATH_INFO
 177                                 // http://bugs.php.net/bug.php?id=31892
 178                                 // Also reported when ini_get('cgi.fix_pathinfo')==false
 179                                 $matches['title'] = substr( $_SERVER['ORIG_PATH_INFO'], 1 );
 180
 181                         } elseif ( isset( $_SERVER['PATH_INFO'] ) && $_SERVER['PATH_INFO'] != '' ) {
 182                                 // Regular old PATH_INFO yay
 183                                 $matches['title'] = substr( $_SERVER['PATH_INFO'], 1 );
 184                         }
 185                 }
 186
 187                 return $matches;
 188         }
 189
 190         /**
 191          * Work out an appropriate URL prefix containing scheme and host, based on
 192          * information detected from $_SERVER
 193          *
 194          * @return string
 195          */
 196         public static function detectServer() {
 197                 global $wgAssumeProxiesUseDefaultProtocolPorts;
 198
 199                 $proto = self::detectProtocol();
 200                 $stdPort = $proto === 'https' ? 443 : 80;
 201
 202                 $varNames = [ 'HTTP_HOST', 'SERVER_NAME', 'HOSTNAME', 'SERVER_ADDR' ];
 203                 $host = 'localhost';
 204                 $port = $stdPort;
 205                 foreach ( $varNames as $varName ) {
 206                         if ( !isset( $_SERVER[$varName] ) ) {
 207                                 continue;
 208                         }
 209
 210                         $parts = IP::splitHostAndPort( $_SERVER[$varName] );
 211                         if ( !$parts ) {
 212                                 // Invalid, do not use
 213                                 continue;
 214                         }
 215
 216                         $host = $parts[0];
 217                         if ( $wgAssumeProxiesUseDefaultProtocolPorts && isset( $_SERVER['HTTP_X_FORWARDED_PROTO'] ) ) {
 218                                 // Bug 70021: Assume that upstream proxy is running on the default
 219                                 // port based on the protocol. We have no reliable way to determine
 220                                 // the actual port in use upstream.
 221                                 $port = $stdPort;
 222                         } elseif ( $parts[1] === false ) {
 223                                 if ( isset( $_SERVER['SERVER_PORT'] ) ) {
 224                                         $port = $_SERVER['SERVER_PORT'];
 225                                 } // else leave it as $stdPort
 226                         } else {
 227                                 $port = $parts[1];
 228                         }
 229                         break;
 230                 }
 231
 232                 return $proto . '://' . IP::combineHostAndPort( $host, $port, $stdPort );
 233         }
 234
 235         /**
 236          * Detect the protocol from $_SERVER.
 237          * This is for use prior to Setup.php, when no WebRequest object is available.
 238          * At other times, use the non-static function getProtocol().
 239          *
 240          * @return array
 241          */
 242         public static function detectProtocol() {
 243                 if ( ( !empty( $_SERVER['HTTPS'] ) && $_SERVER['HTTPS'] !== 'off' ) ||
 244                         ( isset( $_SERVER['HTTP_X_FORWARDED_PROTO'] ) &&
 245                         $_SERVER['HTTP_X_FORWARDED_PROTO'] === 'https' ) ) {
 246                         return 'https';
 247                 } else {
 248                         return 'http';
 249                 }
 250         }
 251
 252         /**
 253          * Get the number of seconds to have elapsed since request start,
 254          * in fractional seconds, with microsecond resolution.
 255          *
 256          * @return float
 257          * @since 1.25
 258          */
 259         public function getElapsedTime() {
 260                 return microtime( true ) - $this->requestTime;
 261         }
 262
 263         /**
 264          * Get the unique request ID.
 265          * This is either the value of the UNIQUE_ID envvar (if present) or a
 266          * randomly-generated 24-character string.
 267          *
 268          * @return string
 269          * @since 1.27
 270          */
 271         public static function getRequestId() {
 272                 if ( !self::$reqId ) {
 273                         self::$reqId = isset( $_SERVER['UNIQUE_ID'] )
 274                                 ? $_SERVER['UNIQUE_ID'] : wfRandomString( 24 );
 275                 }
 276
 277                 return self::$reqId;
 278         }
 279
 280         /**
 281          * Override the unique request ID. This is for sub-requests, such as jobs,
 282          * that wish to use the same id but are not part of the same execution context.
 283          *
 284          * @param string $id
 285          * @since 1.27
 286          */
 287         public static function overrideRequestId( $id ) {
 288                 self::$reqId = $id;
 289         }
 290
 291         /**
 292          * Get the current URL protocol (http or https)
 293          * @return string
 294          */
 295         public function getProtocol() {
 296                 if ( $this->protocol === null ) {
 297                         $this->protocol = self::detectProtocol();
 298                 }
 299                 return $this->protocol;
 300         }
 301
 302         /**
 303          * Check for title, action, and/or variant data in the URL
 304          * and interpolate it into the GET variables.
 305          * This should only be run after $wgContLang is available,
 306          * as we may need the list of language variants to determine
 307          * available variant URLs.
 308          */
 309         public function interpolateTitle() {
 310                 // bug 16019: title interpolation on API queries is useless and sometimes harmful
 311                 if ( defined( 'MW_API' ) ) {
 312                         return;
 313                 }
 314
 315                 $matches = self::getPathInfo( 'title' );
 316                 foreach ( $matches as $key => $val ) {
 317                         $this->data[$key] = $_GET[$key] = $_REQUEST[$key] = $val;
 318                 }
 319         }
 320
 321         /**
 322          * URL rewriting function; tries to extract page title and,
 323          * optionally, one other fixed parameter value from a URL path.
 324          *
 325          * @param string $path The URL path given from the client
 326          * @param array $bases One or more URLs, optionally with $1 at the end
 327          * @param string|bool $key If provided, the matching key in $bases will be
 328          *    passed on as the value of this URL parameter
 329          * @return array Array of URL variables to interpolate; empty if no match
 330          */
 331         static function extractTitle( $path, $bases, $key = false ) {
 332                 foreach ( (array)$bases as $keyValue => $base ) {
 333                         // Find the part after $wgArticlePath
 334                         $base = str_replace( '$1', '', $base );
 335                         $baseLen = strlen( $base );
 336                         if ( substr( $path, 0, $baseLen ) == $base ) {
 337                                 $raw = substr( $path, $baseLen );
 338                                 if ( $raw !== '' ) {
 339                                         $matches = [ 'title' => rawurldecode( $raw ) ];
 340                                         if ( $key ) {
 341                                                 $matches[$key] = $keyValue;
 342                                         }
 343                                         return $matches;
 344                                 }
 345                         }
 346                 }
 347                 return [];
 348         }
 349
 350         /**
 351          * Recursively normalizes UTF-8 strings in the given array.
 352          *
 353          * @param string|array $data
 354          * @return array|string Cleaned-up version of the given
 355          * @private
 356          */
 357         public function normalizeUnicode( $data ) {
 358                 if ( is_array( $data ) ) {
 359                         foreach ( $data as $key => $val ) {
 360                                 $data[$key] = $this->normalizeUnicode( $val );
 361                         }
 362                 } else {
 363                         global $wgContLang;
 364                         $data = isset( $wgContLang ) ?
 365                                 $wgContLang->normalize( $data ) :
 366                                 UtfNormal\Validator::cleanUp( $data );
 367                 }
 368                 return $data;
 369         }
 370
 371         /**
 372          * Fetch a value from the given array or return $default if it's not set.
 373          *
 374          * @param array $arr
 375          * @param string $name
 376          * @param mixed $default
 377          * @return mixed
 378          */
 379         private function getGPCVal( $arr, $name, $default ) {
 380                 # PHP is so nice to not touch input data, except sometimes:
 381                 # http://us2.php.net/variables.external#language.variables.external.dot-in-names
 382                 # Work around PHP *feature* to avoid *bugs* elsewhere.
 383                 $name = strtr( $name, '.', '_' );
 384                 if ( isset( $arr[$name] ) ) {
 385                         global $wgContLang;
 386                         $data = $arr[$name];
 387                         if ( isset( $_GET[$name] ) && !is_array( $data ) ) {
 388                                 # Check for alternate/legacy character encoding.
 389                                 if ( isset( $wgContLang ) ) {
 390                                         $data = $wgContLang->checkTitleEncoding( $data );
 391                                 }
 392                         }
 393                         $data = $this->normalizeUnicode( $data );
 394                         return $data;
 395                 } else {
 396                         return $default;
 397                 }
 398         }
 399
 400         /**
 401          * Fetch a scalar from the input without normalization, or return $default
 402          * if it's not set.
 403          *
 404          * Unlike self::getVal(), this does not perform any normalization on the
 405          * input value.
 406          *
 407          * @since 1.28
 408          * @param string $name
 409          * @param string|null $default Optional default
 410          * @return string
 411          */
 412         public function getRawVal( $name, $default = null ) {
 413                 $name = strtr( $name, '.', '_' ); // See comment in self::getGPCVal()
 414                 if ( isset( $this->data[$name] ) && !is_array( $this->data[$name] ) ) {
 415                         $val = $this->data[$name];
 416                 } else {
 417                         $val = $default;
 418                 }
 419                 if ( is_null( $val ) ) {
 420                         return $val;
 421                 } else {
 422                         return (string)$val;
 423                 }
 424         }
 425
 426         /**
 427          * Fetch a scalar from the input or return $default if it's not set.
 428          * Returns a string. Arrays are discarded. Useful for
 429          * non-freeform text inputs (e.g. predefined internal text keys
 430          * selected by a drop-down menu). For freeform input, see getText().
 431          *
 432          * @param string $name
 433          * @param string $default Optional default (or null)
 434          * @return string
 435          */
 436         public function getVal( $name, $default = null ) {
 437                 $val = $this->getGPCVal( $this->data, $name, $default );
 438                 if ( is_array( $val ) ) {
 439                         $val = $default;
 440                 }
 441                 if ( is_null( $val ) ) {
 442                         return $val;
 443                 } else {
 444                         return (string)$val;
 445                 }
 446         }
 447
 448         /**
 449          * Set an arbitrary value into our get/post data.
 450          *
 451          * @param string $key Key name to use
 452          * @param mixed $value Value to set
 453          * @return mixed Old value if one was present, null otherwise
 454          */
 455         public function setVal( $key, $value ) {
 456                 $ret = isset( $this->data[$key] ) ? $this->data[$key] : null;
 457                 $this->data[$key] = $value;
 458                 return $ret;
 459         }
 460
 461         /**
 462          * Unset an arbitrary value from our get/post data.
 463          *
 464          * @param string $key Key name to use
 465          * @return mixed Old value if one was present, null otherwise
 466          */
 467         public function unsetVal( $key ) {
 468                 if ( !isset( $this->data[$key] ) ) {
 469                         $ret = null;
 470                 } else {
 471                         $ret = $this->data[$key];
 472                         unset( $this->data[$key] );
 473                 }
 474                 return $ret;
 475         }
 476
 477         /**
 478          * Fetch an array from the input or return $default if it's not set.
 479          * If source was scalar, will return an array with a single element.
 480          * If no source and no default, returns null.
 481          *
 482          * @param string $name
 483          * @param array $default Optional default (or null)
 484          * @return array
 485          */
 486         public function getArray( $name, $default = null ) {
 487                 $val = $this->getGPCVal( $this->data, $name, $default );
 488                 if ( is_null( $val ) ) {
 489                         return null;
 490                 } else {
 491                         return (array)$val;
 492                 }
 493         }
 494
 495         /**
 496          * Fetch an array of integers, or return $default if it's not set.
 497          * If source was scalar, will return an array with a single element.
 498          * If no source and no default, returns null.
 499          * If an array is returned, contents are guaranteed to be integers.
 500          *
 501          * @param string $name
 502          * @param array $default Option default (or null)
 503          * @return array Array of ints
 504          */
 505         public function getIntArray( $name, $default = null ) {
 506                 $val = $this->getArray( $name, $default );
 507                 if ( is_array( $val ) ) {
 508                         $val = array_map( 'intval', $val );
 509                 }
 510                 return $val;
 511         }
 512
 513         /**
 514          * Fetch an integer value from the input or return $default if not set.
 515          * Guaranteed to return an integer; non-numeric input will typically
 516          * return 0.
 517          *
 518          * @param string $name
 519          * @param int $default
 520          * @return int
 521          */
 522         public function getInt( $name, $default = 0 ) {
 523                 return intval( $this->getVal( $name, $default ) );
 524         }
 525
 526         /**
 527          * Fetch an integer value from the input or return null if empty.
 528          * Guaranteed to return an integer or null; non-numeric input will
 529          * typically return null.
 530          *
 531          * @param string $name
 532          * @return int|null
 533          */
 534         public function getIntOrNull( $name ) {
 535                 $val = $this->getVal( $name );
 536                 return is_numeric( $val )
 537                         ? intval( $val )
 538                         : null;
 539         }
 540
 541         /**
 542          * Fetch a floating point value from the input or return $default if not set.
 543          * Guaranteed to return a float; non-numeric input will typically
 544          * return 0.
 545          *
 546          * @since 1.23
 547          * @param string $name
 548          * @param float $default
 549          * @return float
 550          */
 551         public function getFloat( $name, $default = 0.0 ) {
 552                 return floatval( $this->getVal( $name, $default ) );
 553         }
 554
 555         /**
 556          * Fetch a boolean value from the input or return $default if not set.
 557          * Guaranteed to return true or false, with normal PHP semantics for
 558          * boolean interpretation of strings.
 559          *
 560          * @param string $name
 561          * @param bool $default
 562          * @return bool
 563          */
 564         public function getBool( $name, $default = false ) {
 565                 return (bool)$this->getVal( $name, $default );
 566         }
 567
 568         /**
 569          * Fetch a boolean value from the input or return $default if not set.
 570          * Unlike getBool, the string "false" will result in boolean false, which is
 571          * useful when interpreting information sent from JavaScript.
 572          *
 573          * @param string $name
 574          * @param bool $default
 575          * @return bool
 576          */
 577         public function getFuzzyBool( $name, $default = false ) {
 578                 return $this->getBool( $name, $default ) && strcasecmp( $this->getVal( $name ), 'false' ) !== 0;
 579         }
 580
 581         /**
 582          * Return true if the named value is set in the input, whatever that
 583          * value is (even "0"). Return false if the named value is not set.
 584          * Example use is checking for the presence of check boxes in forms.
 585          *
 586          * @param string $name
 587          * @return bool
 588          */
 589         public function getCheck( $name ) {
 590                 # Checkboxes and buttons are only present when clicked
 591                 # Presence connotes truth, absence false
 592                 return $this->getVal( $name, null ) !== null;
 593         }
 594
 595         /**
 596          * Fetch a text string from the given array or return $default if it's not
 597          * set. Carriage returns are stripped from the text. This should generally
 598          * be used for form "<textarea>" and "<input>" fields, and for
 599          * user-supplied freeform text input.
 600          *
 601          * @param string $name
 602          * @param string $default Optional
 603          * @return string
 604          */
 605         public function getText( $name, $default = '' ) {
 606                 $val = $this->getVal( $name, $default );
 607                 return str_replace( "\r\n", "\n", $val );
 608         }
 609
 610         /**
 611          * Extracts the given named values into an array.
 612          * If no arguments are given, returns all input values.
 613          * No transformation is performed on the values.
 614          *
 615          * @return array
 616          */
 617         public function getValues() {
 618                 $names = func_get_args();
 619                 if ( count( $names ) == 0 ) {
 620                         $names = array_keys( $this->data );
 621                 }
 622
 623                 $retVal = [];
 624                 foreach ( $names as $name ) {
 625                         $value = $this->getGPCVal( $this->data, $name, null );
 626                         if ( !is_null( $value ) ) {
 627                                 $retVal[$name] = $value;
 628                         }
 629                 }
 630                 return $retVal;
 631         }
 632
 633         /**
 634          * Returns the names of all input values excluding those in $exclude.
 635          *
 636          * @param array $exclude
 637          * @return array
 638          */
 639         public function getValueNames( $exclude = [] ) {
 640                 return array_diff( array_keys( $this->getValues() ), $exclude );
 641         }
 642
 643         /**
 644          * Get the values passed in the query string.
 645          * No transformation is performed on the values.
 646          *
 647          * @codeCoverageIgnore
 648          * @return array
 649          */
 650         public function getQueryValues() {
 651                 return $_GET;
 652         }
 653
 654         /**
 655          * Return the contents of the Query with no decoding. Use when you need to
 656          * know exactly what was sent, e.g. for an OAuth signature over the elements.
 657          *
 658          * @codeCoverageIgnore
 659          * @return string
 660          */
 661         public function getRawQueryString() {
 662                 return $_SERVER['QUERY_STRING'];
 663         }
 664
 665         /**
 666          * Return the contents of the POST with no decoding. Use when you need to
 667          * know exactly what was sent, e.g. for an OAuth signature over the elements.
 668          *
 669          * @return string
 670          */
 671         public function getRawPostString() {
 672                 if ( !$this->wasPosted() ) {
 673                         return '';
 674                 }
 675                 return $this->getRawInput();
 676         }
 677
 678         /**
 679          * Return the raw request body, with no processing. Cached since some methods
 680          * disallow reading the stream more than once. As stated in the php docs, this
 681          * does not work with enctype="multipart/form-data".
 682          *
 683          * @return string
 684          */
 685         public function getRawInput() {
 686                 static $input = null;
 687                 if ( $input === null ) {
 688                         $input = file_get_contents( 'php://input' );
 689                 }
 690                 return $input;
 691         }
 692
 693         /**
 694          * Get the HTTP method used for this request.
 695          *
 696          * @return string
 697          */
 698         public function getMethod() {
 699                 return isset( $_SERVER['REQUEST_METHOD'] ) ? $_SERVER['REQUEST_METHOD'] : 'GET';
 700         }
 701
 702         /**
 703          * Returns true if the present request was reached by a POST operation,
 704          * false otherwise (GET, HEAD, or command-line).
 705          *
 706          * Note that values retrieved by the object may come from the
 707          * GET URL etc even on a POST request.
 708          *
 709          * @return bool
 710          */
 711         public function wasPosted() {
 712                 return $this->getMethod() == 'POST';
 713         }
 714
 715         /**
 716          * Return the session for this request
 717          *
 718          * This might unpersist an existing session if it was invalid.
 719          *
 720          * @since 1.27
 721          * @note For performance, keep the session locally if you will be making
 722          *  much use of it instead of calling this method repeatedly.
 723          * @return Session
 724          */
 725         public function getSession() {
 726                 if ( $this->sessionId !== null ) {
 727                         $session = SessionManager::singleton()->getSessionById( (string)$this->sessionId, true, $this );
 728                         if ( $session ) {
 729                                 return $session;
 730                         }
 731                 }
 732
 733                 $session = SessionManager::singleton()->getSessionForRequest( $this );
 734                 $this->sessionId = $session->getSessionId();
 735                 return $session;
 736         }
 737
 738         /**
 739          * Set the session for this request
 740          * @since 1.27
 741          * @private For use by MediaWiki\Session classes only
 742          * @param SessionId $sessionId
 743          */
 744         public function setSessionId( SessionId $sessionId ) {
 745                 $this->sessionId = $sessionId;
 746         }
 747
 748         /**
 749          * Get the session id for this request, if any
 750          * @since 1.27
 751          * @private For use by MediaWiki\Session classes only
 752          * @return SessionId|null
 753          */
 754         public function getSessionId() {
 755                 return $this->sessionId;
 756         }
 757
 758         /**
 759          * Returns true if the request has a persistent session.
 760          * This does not necessarily mean that the user is logged in!
 761          *
 762          * @deprecated since 1.27, use
 763          *  \MediaWiki\Session\SessionManager::singleton()->getPersistedSessionId()
 764          *  instead.
 765          * @return bool
 766          */
 767         public function checkSessionCookie() {
 768                 global $wgInitialSessionId;
 769                 wfDeprecated( __METHOD__, '1.27' );
 770                 return $wgInitialSessionId !== null &&
 771                         $this->getSession()->getId() === (string)$wgInitialSessionId;
 772         }
 773
 774         /**
 775          * Get a cookie from the $_COOKIE jar
 776          *
 777          * @param string $key The name of the cookie
 778          * @param string $prefix A prefix to use for the cookie name, if not $wgCookiePrefix
 779          * @param mixed $default What to return if the value isn't found
 780          * @return mixed Cookie value or $default if the cookie not set
 781          */
 782         public function getCookie( $key, $prefix = null, $default = null ) {
 783                 if ( $prefix === null ) {
 784                         global $wgCookiePrefix;
 785                         $prefix = $wgCookiePrefix;
 786                 }
 787                 return $this->getGPCVal( $_COOKIE, $prefix . $key, $default );
 788         }
 789
 790         /**
 791          * Return the path and query string portion of the main request URI.
 792          * This will be suitable for use as a relative link in HTML output.
 793          *
 794          * @throws MWException
 795          * @return string
 796          */
 797         public static function getGlobalRequestURL() {
 798                 if ( isset( $_SERVER['REQUEST_URI'] ) && strlen( $_SERVER['REQUEST_URI'] ) ) {
 799                         $base = $_SERVER['REQUEST_URI'];
 800                 } elseif ( isset( $_SERVER['HTTP_X_ORIGINAL_URL'] )
 801                         && strlen( $_SERVER['HTTP_X_ORIGINAL_URL'] )
 802                 ) {
 803                         // Probably IIS; doesn't set REQUEST_URI
 804                         $base = $_SERVER['HTTP_X_ORIGINAL_URL'];
 805                 } elseif ( isset( $_SERVER['SCRIPT_NAME'] ) ) {
 806                         $base = $_SERVER['SCRIPT_NAME'];
 807                         if ( isset( $_SERVER['QUERY_STRING'] ) && $_SERVER['QUERY_STRING'] != '' ) {
 808                                 $base .= '?' . $_SERVER['QUERY_STRING'];
 809                         }
 810                 } else {
 811                         // This shouldn't happen!
 812                         throw new MWException( "Web server doesn't provide either " .
 813                                 "REQUEST_URI, HTTP_X_ORIGINAL_URL or SCRIPT_NAME. Report details " .
 814                                 "of your web server configuration to https://phabricator.wikimedia.org/" );
 815                 }
 816                 // User-agents should not send a fragment with the URI, but
 817                 // if they do, and the web server passes it on to us, we
 818                 // need to strip it or we get false-positive redirect loops
 819                 // or weird output URLs
 820                 $hash = strpos( $base, '#' );
 821                 if ( $hash !== false ) {
 822                         $base = substr( $base, 0, $hash );
 823                 }
 824
 825                 if ( $base[0] == '/' ) {
 826                         // More than one slash will look like it is protocol relative
 827                         return preg_replace( '!^/+!', '/', $base );
 828                 } else {
 829                         // We may get paths with a host prepended; strip it.
 830                         return preg_replace( '!^[^:]+://[^/]+/+!', '/', $base );
 831                 }
 832         }
 833
 834         /**
 835          * Return the path and query string portion of the request URI.
 836          * This will be suitable for use as a relative link in HTML output.
 837          *
 838          * @throws MWException
 839          * @return string
 840          */
 841         public function getRequestURL() {
 842                 return self::getGlobalRequestURL();
 843         }
 844
 845         /**
 846          * Return the request URI with the canonical service and hostname, path,
 847          * and query string. This will be suitable for use as an absolute link
 848          * in HTML or other output.
 849          *
 850          * If $wgServer is protocol-relative, this will return a fully
 851          * qualified URL with the protocol that was used for this request.
 852          *
 853          * @return string
 854          */
 855         public function getFullRequestURL() {
 856                 return wfExpandUrl( $this->getRequestURL(), PROTO_CURRENT );
 857         }
 858
 859         /**
 860          * @param string $key
 861          * @param string $value
 862          * @return string
 863          */
 864         public function appendQueryValue( $key, $value ) {
 865                 return $this->appendQueryArray( [ $key => $value ] );
 866         }
 867
 868         /**
 869          * Appends or replaces value of query variables.
 870          *
 871          * @param array $array Array of values to replace/add to query
 872          * @return string
 873          */
 874         public function appendQueryArray( $array ) {
 875                 $newquery = $this->getQueryValues();
 876                 unset( $newquery['title'] );
 877                 $newquery = array_merge( $newquery, $array );
 878
 879                 return wfArrayToCgi( $newquery );
 880         }
 881
 882         /**
 883          * Check for limit and offset parameters on the input, and return sensible
 884          * defaults if not given. The limit must be positive and is capped at 5000.
 885          * Offset must be positive but is not capped.
 886          *
 887          * @param int $deflimit Limit to use if no input and the user hasn't set the option.
 888          * @param string $optionname To specify an option other than rclimit to pull from.
 889          * @return int[] First element is limit, second is offset
 890          */
 891         public function getLimitOffset( $deflimit = 50, $optionname = 'rclimit' ) {
 892                 global $wgUser;
 893
 894                 $limit = $this->getInt( 'limit', 0 );
 895                 if ( $limit < 0 ) {
 896                         $limit = 0;
 897                 }
 898                 if ( ( $limit == 0 ) && ( $optionname != '' ) ) {
 899                         $limit = $wgUser->getIntOption( $optionname );
 900                 }
 901                 if ( $limit <= 0 ) {
 902                         $limit = $deflimit;
 903                 }
 904                 if ( $limit > 5000 ) {
 905                         $limit = 5000; # We have *some* limits...
 906                 }
 907
 908                 $offset = $this->getInt( 'offset', 0 );
 909                 if ( $offset < 0 ) {
 910                         $offset = 0;
 911                 }
 912
 913                 return [ $limit, $offset ];
 914         }
 915
 916         /**
 917          * Return the path to the temporary file where PHP has stored the upload.
 918          *
 919          * @param string $key
 920          * @return string|null String or null if no such file.
 921          */
 922         public function getFileTempname( $key ) {
 923                 $file = new WebRequestUpload( $this, $key );
 924                 return $file->getTempName();
 925         }
 926
 927         /**
 928          * Return the upload error or 0
 929          *
 930          * @param string $key
 931          * @return int
 932          */
 933         public function getUploadError( $key ) {
 934                 $file = new WebRequestUpload( $this, $key );
 935                 return $file->getError();
 936         }
 937
 938         /**
 939          * Return the original filename of the uploaded file, as reported by
 940          * the submitting user agent. HTML-style character entities are
 941          * interpreted and normalized to Unicode normalization form C, in part
 942          * to deal with weird input from Safari with non-ASCII filenames.
 943          *
 944          * Other than this the name is not verified for being a safe filename.
 945          *
 946          * @param string $key
 947          * @return string|null String or null if no such file.
 948          */
 949         public function getFileName( $key ) {
 950                 $file = new WebRequestUpload( $this, $key );
 951                 return $file->getName();
 952         }
 953
 954         /**
 955          * Return a WebRequestUpload object corresponding to the key
 956          *
 957          * @param string $key
 958          * @return WebRequestUpload
 959          */
 960         public function getUpload( $key ) {
 961                 return new WebRequestUpload( $this, $key );
 962         }
 963
 964         /**
 965          * Return a handle to WebResponse style object, for setting cookies,
 966          * headers and other stuff, for Request being worked on.
 967          *
 968          * @return WebResponse
 969          */
 970         public function response() {
 971                 /* Lazy initialization of response object for this request */
 972                 if ( !is_object( $this->response ) ) {
 973                         $class = ( $this instanceof FauxRequest ) ? 'FauxResponse' : 'WebResponse';
 974                         $this->response = new $class();
 975                 }
 976                 return $this->response;
 977         }
 978
 979         /**
 980          * Initialise the header list
 981          */
 982         protected function initHeaders() {
 983                 if ( count( $this->headers ) ) {
 984                         return;
 985                 }
 986
 987                 $apacheHeaders = function_exists( 'apache_request_headers' ) ? apache_request_headers() : false;
 988                 if ( $apacheHeaders ) {
 989                         foreach ( $apacheHeaders as $tempName => $tempValue ) {
 990                                 $this->headers[strtoupper( $tempName )] = $tempValue;
 991                         }
 992                 } else {
 993                         foreach ( $_SERVER as $name => $value ) {
 994                                 if ( substr( $name, 0, 5 ) === 'HTTP_' ) {
 995                                         $name = str_replace( '_', '-', substr( $name, 5 ) );
 996                                         $this->headers[$name] = $value;
 997                                 } elseif ( $name === 'CONTENT_LENGTH' ) {
 998                                         $this->headers['CONTENT-LENGTH'] = $value;
 999                                 }
1000                         }
1001                 }
1002         }
1003
1004         /**
1005          * Get an array containing all request headers
1006          *
1007          * @return array Mapping header name to its value
1008          */
1009         public function getAllHeaders() {
1010                 $this->initHeaders();
1011                 return $this->headers;
1012         }
1013
1014         /**
1015          * Get a request header, or false if it isn't set.
1016          *
1017          * @param string $name Case-insensitive header name
1018          * @param int $flags Bitwise combination of:
1019          *   WebRequest::GETHEADER_LIST  Treat the header as a comma-separated list
1020          *                               of values, as described in RFC 2616 § 4.2.
1021          *                               (since 1.26).
1022          * @return string|array|bool False if header is unset; otherwise the
1023          *  header value(s) as either a string (the default) or an array, if
1024          *  WebRequest::GETHEADER_LIST flag was set.
1025          */
1026         public function getHeader( $name, $flags = 0 ) {
1027                 $this->initHeaders();
1028                 $name = strtoupper( $name );
1029                 if ( !isset( $this->headers[$name] ) ) {
1030                         return false;
1031                 }
1032                 $value = $this->headers[$name];
1033                 if ( $flags & self::GETHEADER_LIST ) {
1034                         $value = array_map( 'trim', explode( ',', $value ) );
1035                 }
1036                 return $value;
1037         }
1038
1039         /**
1040          * Get data from the session
1041          *
1042          * @note Prefer $this->getSession() instead if making multiple calls.
1043          * @param string $key Name of key in the session
1044          * @return mixed
1045          */
1046         public function getSessionData( $key ) {
1047                 return $this->getSession()->get( $key );
1048         }
1049
1050         /**
1051          * Set session data
1052          *
1053          * @note Prefer $this->getSession() instead if making multiple calls.
1054          * @param string $key Name of key in the session
1055          * @param mixed $data
1056          */
1057         public function setSessionData( $key, $data ) {
1058                 $this->getSession()->set( $key, $data );
1059         }
1060
1061         /**
1062          * Check if Internet Explorer will detect an incorrect cache extension in
1063          * PATH_INFO or QUERY_STRING. If the request can't be allowed, show an error
1064          * message or redirect to a safer URL. Returns true if the URL is OK, and
1065          * false if an error message has been shown and the request should be aborted.
1066          *
1067          * @param array $extWhitelist
1068          * @throws HttpError
1069          * @return bool
1070          */
1071         public function checkUrlExtension( $extWhitelist = [] ) {
1072                 $extWhitelist[] = 'php';
1073                 if ( IEUrlExtension::areServerVarsBad( $_SERVER, $extWhitelist ) ) {
1074                         if ( !$this->wasPosted() ) {
1075                                 $newUrl = IEUrlExtension::fixUrlForIE6(
1076                                         $this->getFullRequestURL(), $extWhitelist );
1077                                 if ( $newUrl !== false ) {
1078                                         $this->doSecurityRedirect( $newUrl );
1079                                         return false;
1080                                 }
1081                         }
1082                         throw new HttpError( 403,
1083                                 'Invalid file extension found in the path info or query string.' );
1084                 }
1085                 return true;
1086         }
1087
1088         /**
1089          * Attempt to redirect to a URL with a QUERY_STRING that's not dangerous in
1090          * IE 6. Returns true if it was successful, false otherwise.
1091          *
1092          * @param string $url
1093          * @return bool
1094          */
1095         protected function doSecurityRedirect( $url ) {
1096                 header( 'Location: ' . $url );
1097                 header( 'Content-Type: text/html' );
1098                 $encUrl = htmlspecialchars( $url );
1099                 echo <<<HTML
1100 <html>
1101 <head>
1102 <title>Security redirect</title>
1103 </head>
1104 <body>
1105 <h1>Security redirect</h1>
1106 <p>
1107 We can't serve non-HTML content from the URL you have requested, because
1108 Internet Explorer would interpret it as an incorrect and potentially dangerous
1109 content type.</p>
1110 <p>Instead, please use <a href="$encUrl">this URL</a>, which is the same as the
1111 URL you have requested, except that "&amp;*" is appended. This prevents Internet
1112 Explorer from seeing a bogus file extension.
1113 </p>
1114 </body>
1115 </html>
1116 HTML;
1117                 echo "\n";
1118                 return true;
1119         }
1120
1121         /**
1122          * Parse the Accept-Language header sent by the client into an array
1123          *
1124          * @return array Array( languageCode => q-value ) sorted by q-value in
1125          *   descending order then appearing time in the header in ascending order.
1126          * May contain the "language" '*', which applies to languages other than those explicitly listed.
1127          * This is aligned with rfc2616 section 14.4
1128          * Preference for earlier languages appears in rfc3282 as an extension to HTTP/1.1.
1129          */
1130         public function getAcceptLang() {
1131                 // Modified version of code found at
1132                 // http://www.thefutureoftheweb.com/blog/use-accept-language-header
1133                 $acceptLang = $this->getHeader( 'Accept-Language' );
1134                 if ( !$acceptLang ) {
1135                         return [];
1136                 }
1137
1138                 // Return the language codes in lower case
1139                 $acceptLang = strtolower( $acceptLang );
1140
1141                 // Break up string into pieces (languages and q factors)
1142                 $lang_parse = null;
1143                 preg_match_all(
1144                         '/([a-z]{1,8}(-[a-z]{1,8})*|\*)\s*(;\s*q\s*=\s*(1(\.0{0,3})?|0(\.[0-9]{0,3})?)?)?/',
1145                         $acceptLang,
1146                         $lang_parse
1147                 );
1148
1149                 if ( !count( $lang_parse[1] ) ) {
1150                         return [];
1151                 }
1152
1153                 $langcodes = $lang_parse[1];
1154                 $qvalues = $lang_parse[4];
1155                 $indices = range( 0, count( $lang_parse[1] ) - 1 );
1156
1157                 // Set default q factor to 1
1158                 foreach ( $indices as $index ) {
1159                         if ( $qvalues[$index] === '' ) {
1160                                 $qvalues[$index] = 1;
1161                         } elseif ( $qvalues[$index] == 0 ) {
1162                                 unset( $langcodes[$index], $qvalues[$index], $indices[$index] );
1163                         }
1164                 }
1165
1166                 // Sort list. First by $qvalues, then by order. Reorder $langcodes the same way
1167                 array_multisort( $qvalues, SORT_DESC, SORT_NUMERIC, $indices, $langcodes );
1168
1169                 // Create a list like "en" => 0.8
1170                 $langs = array_combine( $langcodes, $qvalues );
1171
1172                 return $langs;
1173         }
1174
1175         /**
1176          * Fetch the raw IP from the request
1177          *
1178          * @since 1.19
1179          *
1180          * @throws MWException
1181          * @return string
1182          */
1183         protected function getRawIP() {
1184                 if ( !isset( $_SERVER['REMOTE_ADDR'] ) ) {
1185                         return null;
1186                 }
1187
1188                 if ( is_array( $_SERVER['REMOTE_ADDR'] ) || strpos( $_SERVER['REMOTE_ADDR'], ',' ) !== false ) {
1189                         throw new MWException( __METHOD__
1190                                 . " : Could not determine the remote IP address due to multiple values." );
1191                 } else {
1192                         $ipchain = $_SERVER['REMOTE_ADDR'];
1193                 }
1194
1195                 return IP::canonicalize( $ipchain );
1196         }
1197
1198         /**
1199          * Work out the IP address based on various globals
1200          * For trusted proxies, use the XFF client IP (first of the chain)
1201          *
1202          * @since 1.19
1203          *
1204          * @throws MWException
1205          * @return string
1206          */
1207         public function getIP() {
1208                 global $wgUsePrivateIPs;
1209
1210                 # Return cached result
1211                 if ( $this->ip !== null ) {
1212                         return $this->ip;
1213                 }
1214
1215                 # collect the originating ips
1216                 $ip = $this->getRawIP();
1217                 if ( !$ip ) {
1218                         throw new MWException( 'Unable to determine IP.' );
1219                 }
1220
1221                 # Append XFF
1222                 $forwardedFor = $this->getHeader( 'X-Forwarded-For' );
1223                 if ( $forwardedFor !== false ) {
1224                         $isConfigured = IP::isConfiguredProxy( $ip );
1225                         $ipchain = array_map( 'trim', explode( ',', $forwardedFor ) );
1226                         $ipchain = array_reverse( $ipchain );
1227                         array_unshift( $ipchain, $ip );
1228
1229                         # Step through XFF list and find the last address in the list which is a
1230                         # trusted server. Set $ip to the IP address given by that trusted server,
1231                         # unless the address is not sensible (e.g. private). However, prefer private
1232                         # IP addresses over proxy servers controlled by this site (more sensible).
1233                         # Note that some XFF values might be "unknown" with Squid/Varnish.
1234                         foreach ( $ipchain as $i => $curIP ) {
1235                                 $curIP = IP::sanitizeIP( IP::canonicalize( $curIP ) );
1236                                 if ( !$curIP || !isset( $ipchain[$i + 1] ) || $ipchain[$i + 1] === 'unknown'
1237                                         || !IP::isTrustedProxy( $curIP )
1238                                 ) {
1239                                         break; // IP is not valid/trusted or does not point to anything
1240                                 }
1241                                 if (
1242                                         IP::isPublic( $ipchain[$i + 1] ) ||
1243                                         $wgUsePrivateIPs ||
1244                                         IP::isConfiguredProxy( $curIP ) // bug 48919; treat IP as sane
1245                                 ) {
1246                                         // Follow the next IP according to the proxy
1247                                         $nextIP = IP::canonicalize( $ipchain[$i + 1] );
1248                                         if ( !$nextIP && $isConfigured ) {
1249                                                 // We have not yet made it past CDN/proxy servers of this site,
1250                                                 // so either they are misconfigured or there is some IP spoofing.
1251                                                 throw new MWException( "Invalid IP given in XFF '$forwardedFor'." );
1252                                         }
1253                                         $ip = $nextIP;
1254                                         // keep traversing the chain
1255                                         continue;
1256                                 }
1257                                 break;
1258                         }
1259                 }
1260
1261                 # Allow extensions to improve our guess
1262                 Hooks::run( 'GetIP', [ &$ip ] );
1263
1264                 if ( !$ip ) {
1265                         throw new MWException( "Unable to determine IP." );
1266                 }
1267
1268                 wfDebug( "IP: $ip\n" );
1269                 $this->ip = $ip;
1270                 return $ip;
1271         }
1272
1273         /**
1274          * @param string $ip
1275          * @return void
1276          * @since 1.21
1277          */
1278         public function setIP( $ip ) {
1279                 $this->ip = $ip;
1280         }
1281
1282         /**
1283          * Check if this request uses a "safe" HTTP method
1284          *
1285          * Safe methods are verbs (e.g. GET/HEAD/OPTIONS) used for obtaining content. Such requests
1286          * are not expected to mutate content, especially in ways attributable to the client. Verbs
1287          * like POST and PUT are typical of non-safe requests which often change content.
1288          *
1289          * @return bool
1290          * @see https://tools.ietf.org/html/rfc7231#section-4.2.1
1291          * @see https://www.w3.org/Protocols/rfc2616/rfc2616-sec9.html
1292          * @since 1.28
1293          */
1294         public function hasSafeMethod() {
1295                 if ( !isset( $_SERVER['REQUEST_METHOD'] ) ) {
1296                         return false; // CLI mode
1297                 }
1298
1299                 return in_array( $_SERVER['REQUEST_METHOD'], [ 'GET', 'HEAD', 'OPTIONS', 'TRACE' ] );
1300         }
1301
1302         /**
1303          * Whether this request should be identified as being "safe"
1304          *
1305          * This means that the client is not requesting any state changes and that database writes
1306          * are not inherently required. Ideally, no visible updates would happen at all. If they
1307          * must, then they should not be publically attributed to the end user.
1308          *
1309          * In more detail:
1310          *   - Cache populations and refreshes MAY occur.
1311          *   - Private user session updates and private server logging MAY occur.
1312          *   - Updates to private viewing activity data MAY occur via DeferredUpdates.
1313          *   - Other updates SHOULD NOT occur (e.g. modifying content assets).
1314          *
1315          * @return bool
1316          * @see https://tools.ietf.org/html/rfc7231#section-4.2.1
1317          * @see https://www.w3.org/Protocols/rfc2616/rfc2616-sec9.html
1318          * @since 1.28
1319          */
1320         public function isSafeRequest() {
1321                 if ( $this->markedAsSafe && $this->wasPosted() ) {
1322                         return true; // marked as a "safe" POST
1323                 }
1324
1325                 return $this->hasSafeMethod();
1326         }
1327
1328         /**
1329          * Mark this request as identified as being nullipotent even if it is a POST request
1330          *
1331          * POST requests are often used due to the need for a client payload, even if the request
1332          * is otherwise equivalent to a "safe method" request.
1333          *
1334          * @see https://tools.ietf.org/html/rfc7231#section-4.2.1
1335          * @see https://www.w3.org/Protocols/rfc2616/rfc2616-sec9.html
1336          * @since 1.28
1337          */
1338         public function markAsSafeRequest() {
1339                 $this->markedAsSafe = true;
1340         }
1341 }