summaryrefslogtreecommitdiff
path: root/thumb.php
blob: c53eb2a5ab23c02db6d087a1c9d93ea20956cfc1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
<?php
/**
 * PHP script to stream out an image thumbnail.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 * http://www.gnu.org/copyleft/gpl.html
 *
 * @file
 * @ingroup Media
 */

define( 'MW_NO_OUTPUT_COMPRESSION', 1 );
if ( isset( $_SERVER['MW_COMPILED'] ) ) {
	require( 'core/includes/WebStart.php' );
} else {
	require( __DIR__ . '/includes/WebStart.php' );
}

// Don't use fancy mime detection, just check the file extension for jpg/gif/png
$wgTrivialMimeDetection = true;

if ( defined( 'THUMB_HANDLER' ) ) {
	// Called from thumb_handler.php via 404; extract params from the URI...
	wfThumbHandle404();
} else {
	// Called directly, use $_REQUEST params
	wfThumbHandleRequest();
}
wfLogProfilingData();

//--------------------------------------------------------------------------

/**
 * Handle a thumbnail request via query parameters
 *
 * @return void
 */
function wfThumbHandleRequest() {
	$params = get_magic_quotes_gpc()
		? array_map( 'stripslashes', $_REQUEST )
		: $_REQUEST;

	wfStreamThumb( $params ); // stream the thumbnail
}

/**
 * Handle a thumbnail request via thumbnail file URL
 *
 * @return void
 */
function wfThumbHandle404() {
	# lighttpd puts the original request in REQUEST_URI, while sjs sets
	# that to the 404 handler, and puts the original request in REDIRECT_URL.
	if ( isset( $_SERVER['REDIRECT_URL'] ) ) {
		# The URL is un-encoded, so put it back how it was
		$uriPath = str_replace( "%2F", "/", urlencode( $_SERVER['REDIRECT_URL'] ) );
	} else {
		$uriPath = $_SERVER['REQUEST_URI'];
	}
	# Just get the URI path (REDIRECT_URL/REQUEST_URI is either a full URL or a path)
	if ( substr( $uriPath, 0, 1 ) !== '/' ) {
		$bits = wfParseUrl( $uriPath );
		if ( $bits && isset( $bits['path'] ) ) {
			$uriPath = $bits['path'];
		} else {
			wfThumbError( 404, 'The source file for the specified thumbnail does not exist.' );
			return;
		}
	}

	$params = wfExtractThumbParams( $uriPath ); // basic wiki URL param extracting
	if ( $params == null ) {
		wfThumbError( 404, 'The source file for the specified thumbnail does not exist.' );
		return;
	}

	wfStreamThumb( $params ); // stream the thumbnail
}

/**
 * Stream a thumbnail specified by parameters
 *
 * @param $params Array
 * @return void
 */
function wfStreamThumb( array $params ) {
	global $wgVaryOnXFP;
	wfProfileIn( __METHOD__ );

	$headers = array(); // HTTP headers to send

	$fileName = isset( $params['f'] ) ? $params['f'] : '';
	unset( $params['f'] );

	// Backwards compatibility parameters
	if ( isset( $params['w'] ) ) {
		$params['width'] = $params['w'];
		unset( $params['w'] );
	}
	if ( isset( $params['p'] ) ) {
		$params['page'] = $params['p'];
	}
	unset( $params['r'] ); // ignore 'r' because we unconditionally pass File::RENDER

	// Is this a thumb of an archived file?
	$isOld = ( isset( $params['archived'] ) && $params['archived'] );
	unset( $params['archived'] ); // handlers don't care

	// Is this a thumb of a temp file?
	$isTemp = ( isset( $params['temp'] ) && $params['temp'] );
	unset( $params['temp'] ); // handlers don't care

	// Some basic input validation
	$fileName = strtr( $fileName, '\\/', '__' );

	// Actually fetch the image. Method depends on whether it is archived or not.
	if ( $isTemp ) {
		$repo = RepoGroup::singleton()->getLocalRepo()->getTempRepo();
		$img = new UnregisteredLocalFile( null, $repo,
			# Temp files are hashed based on the name without the timestamp.
			# The thumbnails will be hashed based on the entire name however.
			# @TODO: fix this convention to actually be reasonable.
			$repo->getZonePath( 'public' ) . '/' . $repo->getTempHashPath( $fileName ) . $fileName
		);
	} elseif ( $isOld ) {
		// Format is <timestamp>!<name>
		$bits = explode( '!', $fileName, 2 );
		if ( count( $bits ) != 2 ) {
			wfThumbError( 404, wfMessage( 'badtitletext' )->text() );
			wfProfileOut( __METHOD__ );
			return;
		}
		$title = Title::makeTitleSafe( NS_FILE, $bits[1] );
		if ( !$title ) {
			wfThumbError( 404, wfMessage( 'badtitletext' )->text() );
			wfProfileOut( __METHOD__ );
			return;
		}
		$img = RepoGroup::singleton()->getLocalRepo()->newFromArchiveName( $title, $fileName );
	} else {
		$img = wfLocalFile( $fileName );
	}

	// Check permissions if there are read restrictions
	$varyHeader = array();
	if ( !in_array( 'read', User::getGroupPermissions( array( '*' ) ), true ) ) {
		if ( !$img->getTitle() || !$img->getTitle()->userCan( 'read' ) ) {
			wfThumbError( 403, 'Access denied. You do not have permission to access ' .
				'the source file.' );
			wfProfileOut( __METHOD__ );
			return;
		}
		$headers[] = 'Cache-Control: private';
		$varyHeader[] = 'Cookie';
	}

	// Check the source file storage path
	if ( !$img ) {
		wfThumbError( 404, wfMessage( 'badtitletext' )->text() );
		wfProfileOut( __METHOD__ );
		return;
	}
	if ( !$img->exists() ) {
		wfThumbError( 404, 'The source file for the specified thumbnail does not exist.' );
		wfProfileOut( __METHOD__ );
		return;
	}
	$sourcePath = $img->getPath();
	if ( $sourcePath === false ) {
		wfThumbError( 500, 'The source file is not locally accessible.' );
		wfProfileOut( __METHOD__ );
		return;
	}

	// Check IMS against the source file
	// This means that clients can keep a cached copy even after it has been deleted on the server
	if ( !empty( $_SERVER['HTTP_IF_MODIFIED_SINCE'] ) ) {
		// Fix IE brokenness
		$imsString = preg_replace( '/;.*$/', '', $_SERVER["HTTP_IF_MODIFIED_SINCE"] );
		// Calculate time
		wfSuppressWarnings();
		$imsUnix = strtotime( $imsString );
		wfRestoreWarnings();
		$sourceTsUnix = wfTimestamp( TS_UNIX, $img->getTimestamp() );
		if ( $sourceTsUnix <= $imsUnix ) {
			header( 'HTTP/1.1 304 Not Modified' );
			wfProfileOut( __METHOD__ );
			return;
		}
	}

	$thumbName = $img->thumbName( $params );
	if ( !strlen( $thumbName ) ) { // invalid params?
		wfThumbError( 400, 'The specified thumbnail parameters are not valid.' );
		wfProfileOut( __METHOD__ );
		return;
	}

	$disposition = $img->getThumbDisposition( $thumbName );
	$headers[] = "Content-Disposition: $disposition";

	// Stream the file if it exists already...
	try {
		$thumbName2 = $img->thumbName( $params, File::THUMB_FULL_NAME ); // b/c; "long" style
		// For 404 handled thumbnails, we only use the the base name of the URI
		// for the thumb params and the parent directory for the source file name.
		// Check that the zone relative path matches up so squid caches won't pick
		// up thumbs that would not be purged on source file deletion (bug 34231).
		if ( isset( $params['rel404'] ) ) { // thumbnail was handled via 404
			if ( urldecode( $params['rel404'] ) === $img->getThumbRel( $thumbName ) ) {
				// Request for the canonical thumbnail name
			} elseif ( urldecode( $params['rel404'] ) === $img->getThumbRel( $thumbName2 ) ) {
				// Request for the "long" thumbnail name; redirect to canonical name
				$response = RequestContext::getMain()->getRequest()->response();
				$response->header( "HTTP/1.1 301 " . HttpStatus::getMessage( 301 ) );
				$response->header( 'Location: ' . wfExpandUrl( $img->getThumbUrl( $thumbName ), PROTO_CURRENT ) );
				$response->header( 'Expires: ' .
					gmdate( 'D, d M Y H:i:s', time() + 7*86400 ) . ' GMT' );
				if ( $wgVaryOnXFP ) {
					$varyHeader[] = 'X-Forwarded-Proto';
				}
				$response->header( 'Vary: ' . implode( ', ', $varyHeader ) );
				wfProfileOut( __METHOD__ );
				return;
			} else {
				wfThumbError( 404, 'The given path of the specified thumbnail is incorrect.' );
				wfProfileOut( __METHOD__ );
				return;
			}
		}
		$thumbPath = $img->getThumbPath( $thumbName );
		if ( $img->getRepo()->fileExists( $thumbPath ) ) {
			$headers[] = 'Vary: ' . implode( ', ', $varyHeader );
			$img->getRepo()->streamFile( $thumbPath, $headers );
			wfProfileOut( __METHOD__ );
			return;
		}
	} catch ( MWException $e ) {
		wfThumbError( 500, $e->getHTML() );
		wfProfileOut( __METHOD__ );
		return;
	}
	$headers[] = 'Vary: ' . implode( ', ', $varyHeader );

	// Thumbnail isn't already there, so create the new thumbnail...
	try {
		$thumb = $img->transform( $params, File::RENDER_NOW );
	} catch ( Exception $ex ) {
		// Tried to select a page on a non-paged file?
		$thumb = false;
	}

	// Check for thumbnail generation errors...
	$errorMsg = false;
	$msg = wfMessage( 'thumbnail_error' );
	if ( !$thumb ) {
		$errorMsg = $msg->rawParams( 'File::transform() returned false' )->escaped();
	} elseif ( $thumb->isError() ) {
		$errorMsg = $thumb->getHtmlMsg();
	} elseif ( !$thumb->hasFile() ) {
		$errorMsg = $msg->rawParams( 'No path supplied in thumbnail object' )->escaped();
	} elseif ( $thumb->fileIsSource() ) {
		$errorMsg = $msg->
			rawParams( 'Image was not scaled, is the requested width bigger than the source?' )->escaped();
	}

	if ( $errorMsg !== false ) {
		wfThumbError( 500, $errorMsg );
	} else {
		// Stream the file if there were no errors
		$thumb->streamFile( $headers );
	}

	wfProfileOut( __METHOD__ );
}

/**
 * Extract the required params for thumb.php from the thumbnail request URI.
 * At least 'width' and 'f' should be set if the result is an array.
 *
 * @param $uriPath String Thumbnail request URI path
 * @return Array|null associative params array or null
 */
function wfExtractThumbParams( $uriPath ) {
	$repo = RepoGroup::singleton()->getLocalRepo();

	// Zone URL might be relative ("/images") or protocol-relative ("//lang.site/image")
	$zoneUriPath = $repo->getZoneHandlerUrl( 'thumb' )
		? $repo->getZoneHandlerUrl( 'thumb' ) // custom URL
		: $repo->getZoneUrl( 'thumb' ); // default to main URL
	$bits = wfParseUrl( wfExpandUrl( $zoneUriPath, PROTO_INTERNAL ) );
	if ( $bits && isset( $bits['path'] ) ) {
		$zoneUriPath = $bits['path'];
	} else {
		return null; // not a valid thumbnail URL
	}

	$hashDirReg = $subdirReg = '';
	for ( $i = 0; $i < $repo->getHashLevels(); $i++ ) {
		$subdirReg .= '[0-9a-f]';
		$hashDirReg .= "$subdirReg/";
	}
	$zoneReg = preg_quote( $zoneUriPath ); // regex for thumb zone URI

	// Check if this is a thumbnail of an original in the local file repo
	if ( preg_match( "!^$zoneReg/((archive/)?$hashDirReg([^/]*)/([^/]*))$!", $uriPath, $m ) ) {
		list( /*all*/, $rel, $archOrTemp, $filename, $thumbname ) = $m;
	// Check if this is a thumbnail of an temp file in the local file repo
	} elseif ( preg_match( "!^$zoneReg/(temp/)($hashDirReg([^/]*)/([^/]*))$!", $uriPath, $m ) ) {
		list( /*all*/, $archOrTemp, $rel, $filename, $thumbname ) = $m;
	} else {
		return null; // not a valid looking thumbnail request
	}

	$filename = urldecode( $filename );
	$thumbname = urldecode( $thumbname );

	$params = array( 'f' => $filename, 'rel404' => $rel );
	if ( $archOrTemp === 'archive/' ) {
		$params['archived'] = 1;
	} elseif ( $archOrTemp === 'temp/' ) {
		$params['temp'] = 1;
	}

	// Check if the parameters can be extracted from the thumbnail name...
	if ( preg_match( '!^(page(\d*)-)*(\d*)px-[^/]*$!', $thumbname, $matches ) ) {
		list( /* all */, $pagefull, $pagenum, $size ) = $matches;
		$params['width'] = $size;
		if ( $pagenum ) {
			$params['page'] = $pagenum;
		}
		return $params; // valid thumbnail URL
	// Hooks return false if they manage to *resolve* the parameters
	} elseif ( !wfRunHooks( 'ExtractThumbParameters', array( $thumbname, &$params ) ) ) {
		return $params; // valid thumbnail URL (via extension or config)
	}

	return null; // not a valid thumbnail URL
}

/**
 * Output a thumbnail generation error message
 *
 * @param $status integer
 * @param $msg string
 * @return void
 */
function wfThumbError( $status, $msg ) {
	global $wgShowHostnames;

	header( 'Cache-Control: no-cache' );
	header( 'Content-Type: text/html; charset=utf-8' );
	if ( $status == 404 ) {
		header( 'HTTP/1.1 404 Not found' );
	} elseif ( $status == 403 ) {
		header( 'HTTP/1.1 403 Forbidden' );
		header( 'Vary: Cookie' );
	} else {
		header( 'HTTP/1.1 500 Internal server error' );
	}
	if ( $wgShowHostnames ) {
		$url = htmlspecialchars( isset( $_SERVER['REQUEST_URI'] ) ? $_SERVER['REQUEST_URI'] : '' );
		$hostname = htmlspecialchars( wfHostname() );
		$debug = "<!-- $url -->\n<!-- $hostname -->\n";
	} else {
		$debug = "";
	}
	echo <<<EOT
<html><head><title>Error generating thumbnail</title></head>
<body>
<h1>Error generating thumbnail</h1>
<p>
$msg
</p>
$debug
</body>
</html>

EOT;
}