1<?php 2 3/** 4 * Utilities for handling HTTP related tasks 5 * 6 * @license GPL 2 (http://www.gnu.org/licenses/gpl.html) 7 * @author Andreas Gohr <andi@splitbrain.org> 8 */ 9 10define('HTTP_MULTIPART_BOUNDARY', 'D0KuW1K1B0uNDARY'); 11define('HTTP_HEADER_LF', "\r\n"); 12define('HTTP_CHUNK_SIZE', 16 * 1024); 13 14/** 15 * Checks and sets HTTP headers for conditional HTTP requests 16 * 17 * @param int $timestamp lastmodified time of the cache file 18 * @returns void or exits with previously header() commands executed 19 * @link http://simonwillison.net/2003/Apr/23/conditionalGet/ 20 * 21 * @author Simon Willison <swillison@gmail.com> 22 */ 23function http_conditionalRequest($timestamp) 24{ 25 global $INPUT; 26 27 // A PHP implementation of conditional get, see 28 // http://fishbowl.pastiche.org/2002/10/21/http_conditional_get_for_rss_hackers/ 29 $last_modified = substr(gmdate('r', $timestamp), 0, -5) . 'GMT'; 30 $etag = '"' . md5($last_modified) . '"'; 31 // Send the headers 32 header("Last-Modified: $last_modified"); 33 header("ETag: $etag"); 34 // See if the client has provided the required headers 35 $if_modified_since = $INPUT->server->filter('stripslashes')->str('HTTP_IF_MODIFIED_SINCE', false); 36 $if_none_match = $INPUT->server->filter('stripslashes')->str('HTTP_IF_NONE_MATCH', false); 37 38 if (!$if_modified_since && !$if_none_match) { 39 return; 40 } 41 42 // At least one of the headers is there - check them 43 if ($if_none_match && $if_none_match != $etag) { 44 return; // etag is there but doesn't match 45 } 46 47 if ($if_modified_since && $if_modified_since != $last_modified) { 48 return; // if-modified-since is there but doesn't match 49 } 50 51 // Nothing has changed since their last request - serve a 304 and exit 52 header('HTTP/1.0 304 Not Modified'); 53 54 // don't produce output, even if compression is on 55 @ob_end_clean(); 56 exit; 57} 58 59/** 60 * Let the webserver send the given file via x-sendfile method 61 * 62 * @param string $file absolute path of file to send 63 * @returns void or exits with previous header() commands executed 64 * @author Chris Smith <chris@jalakai.co.uk> 65 * 66 */ 67function http_sendfile($file) 68{ 69 global $conf; 70 71 //use x-sendfile header to pass the delivery to compatible web servers 72 if ($conf['xsendfile'] == 1) { 73 header("X-LIGHTTPD-send-file: $file"); 74 ob_end_clean(); 75 exit; 76 } elseif ($conf['xsendfile'] == 2) { 77 header("X-Sendfile: $file"); 78 ob_end_clean(); 79 exit; 80 } elseif ($conf['xsendfile'] == 3) { 81 // FS#2388, #2895 nginx needs an internal redirect URL, not a file path. 82 header("X-Accel-Redirect: " . http_xaccel_url($file)); 83 ob_end_clean(); 84 exit; 85 } 86} 87 88/** 89 * Build the internal redirect URL for nginx's X-Accel-Redirect header 90 * 91 * Construct a request path from a given file path that nginx can resolve to the file through an `internal` location. 92 * A. Files inside the DokuWiki installation are returned as relative paths. 93 * B. Standard data directory paths are returned as /data/* paths regardless of their actual location (reconfigured 94 * savedir or mediadir). 95 * C. Paths outside the DokuWiki installation are returned with a /_x_accel_redirect/ prefix 96 * 97 * Nginx admins need to configure appropriate internal location mappings. 98 * 99 * @param string $file absolute path of the file to send 100 * @return string the relative URL for the X-Accel-Redirect header 101 */ 102function http_xaccel_url($file) 103{ 104 global $conf; 105 106 $file = fullpath($file); 107 108 if (str_starts_with($file, DOKU_INC)) { 109 // A. files inside the DokuWiki directory: keep their path relative to the root 110 $path = substr($file, strlen(DOKU_INC)); 111 } else { 112 // C. files outside DokuWiki and its data dirs: add prefix (overridden below if a root matches) 113 $path = '_x_accel_redirect/' . ltrim($file, '/'); 114 115 // B. files in a relocated data directory: map back to their default URL below data/ 116 $roots = [ 117 $conf['mediadir'] => 'data/media/', 118 $conf['mediaolddir'] => 'data/media_attic/', 119 $conf['cachedir'] => 'data/cache/', 120 $conf['savedir'] => 'data/', 121 ]; 122 // match the most specific (longest) root first so nested directories win 123 uksort($roots, fn($a, $b) => strlen($b) - strlen($a)); 124 125 foreach ($roots as $root => $logical) { 126 if (str_starts_with($file, $root . '/')) { 127 $path = $logical . substr($file, strlen($root) + 1); 128 break; 129 } 130 } 131 } 132 133 // URL-encode each segment (nginx URL-decodes the redirect target before resolving it) 134 return DOKU_REL . implode('/', array_map(rawurlencode(...), explode('/', $path))); 135} 136 137/** 138 * Send file contents supporting rangeRequests 139 * 140 * This function exits the running script 141 * 142 * @param resource $fh - file handle for an already open file 143 * @param int $size - size of the whole file 144 * @param int $mime - MIME type of the file 145 * 146 * @author Andreas Gohr <andi@splitbrain.org> 147 */ 148function http_rangeRequest($fh, $size, $mime) 149{ 150 global $INPUT; 151 152 $ranges = []; 153 $isrange = false; 154 155 header('Accept-Ranges: bytes'); 156 157 if (!$INPUT->server->has('HTTP_RANGE')) { 158 // no range requested - send the whole file 159 $ranges[] = [0, $size, $size]; 160 } else { 161 $t = explode('=', $INPUT->server->str('HTTP_RANGE')); 162 if (!$t[0] == 'bytes') { 163 // we only understand byte ranges - send the whole file 164 $ranges[] = [0, $size, $size]; 165 } else { 166 $isrange = true; 167 // handle multiple ranges 168 $r = explode(',', $t[1]); 169 foreach ($r as $x) { 170 $p = explode('-', $x); 171 $start = (int)$p[0]; 172 $end = (int)$p[1]; 173 if (!$end) $end = $size - 1; 174 if ($start > $end || $start > $size || $end > $size) { 175 header('HTTP/1.1 416 Requested Range Not Satisfiable'); 176 echo 'Bad Range Request!'; 177 exit; 178 } 179 $len = $end - $start + 1; 180 $ranges[] = [$start, $end, $len]; 181 } 182 } 183 } 184 $parts = count($ranges); 185 186 // now send the type and length headers 187 if (!$isrange) { 188 header("Content-Type: $mime", true); 189 } else { 190 header('HTTP/1.1 206 Partial Content'); 191 if ($parts == 1) { 192 header("Content-Type: $mime", true); 193 } else { 194 header('Content-Type: multipart/byteranges; boundary=' . HTTP_MULTIPART_BOUNDARY, true); 195 } 196 } 197 198 // send all ranges 199 for ($i = 0; $i < $parts; $i++) { 200 [$start, $end, $len] = $ranges[$i]; 201 202 // multipart or normal headers 203 if ($parts > 1) { 204 echo HTTP_HEADER_LF . '--' . HTTP_MULTIPART_BOUNDARY . HTTP_HEADER_LF; 205 echo "Content-Type: $mime" . HTTP_HEADER_LF; 206 echo "Content-Range: bytes $start-$end/$size" . HTTP_HEADER_LF; 207 echo HTTP_HEADER_LF; 208 } else { 209 header("Content-Length: $len"); 210 if ($isrange) { 211 header("Content-Range: bytes $start-$end/$size"); 212 } 213 } 214 215 // send file content 216 fseek($fh, $start); //seek to start of range 217 $chunk = ($len > HTTP_CHUNK_SIZE) ? HTTP_CHUNK_SIZE : $len; 218 while (!feof($fh) && $chunk > 0) { 219 @set_time_limit(30); // large files can take a lot of time 220 echo fread($fh, $chunk); 221 flush(); 222 $len -= $chunk; 223 $chunk = ($len > HTTP_CHUNK_SIZE) ? HTTP_CHUNK_SIZE : $len; 224 } 225 } 226 if ($parts > 1) { 227 echo HTTP_HEADER_LF . '--' . HTTP_MULTIPART_BOUNDARY . '--' . HTTP_HEADER_LF; 228 } 229 230 // everything should be done here, exit (or return if testing) 231 if (defined('SIMPLE_TEST')) return; 232 exit; 233} 234 235/** 236 * Check for a gzipped version and create if necessary 237 * 238 * return true if there exists a gzip version of the uncompressed file 239 * (samepath/samefilename.sameext.gz) created after the uncompressed file 240 * 241 * @param string $uncompressed_file 242 * @return bool 243 * @author Chris Smith <chris.eureka@jalakai.co.uk> 244 * 245 */ 246function http_gzip_valid($uncompressed_file) 247{ 248 if (!DOKU_HAS_GZIP) return false; 249 250 $gzip = $uncompressed_file . '.gz'; 251 if (filemtime($gzip) < filemtime($uncompressed_file)) { // filemtime returns false (0) if file doesn't exist 252 return copy($uncompressed_file, 'compress.zlib://' . $gzip); 253 } 254 255 return true; 256} 257 258/** 259 * Set HTTP headers and echo cachefile, if useable 260 * 261 * This function handles output of cacheable resource files. It ses the needed 262 * HTTP headers. If a useable cache is present, it is passed to the web server 263 * and the script is terminated. 264 * 265 * @param string $cache cache file name 266 * @param bool $cache_ok if cache can be used 267 */ 268function http_cached($cache, $cache_ok) 269{ 270 global $conf; 271 272 // check cache age & handle conditional request 273 // since the resource files are timestamped, we can use a long max age: 1 year 274 header('Cache-Control: public, max-age=31536000'); 275 header('Pragma: public'); 276 if ($cache_ok) { 277 http_conditionalRequest(filemtime($cache)); 278 if ($conf['allowdebug']) header("X-CacheUsed: $cache"); 279 280 // finally send output 281 if ($conf['gzip_output'] && http_gzip_valid($cache)) { 282 header('Vary: Accept-Encoding'); 283 header('Content-Encoding: gzip'); 284 readfile($cache . ".gz"); 285 } else { 286 http_sendfile($cache); 287 readfile($cache); 288 } 289 exit; 290 } 291 292 http_conditionalRequest(time()); 293} 294 295/** 296 * Cache content and print it 297 * 298 * @param string $file file name 299 * @param string $content 300 */ 301function http_cached_finish($file, $content) 302{ 303 global $conf; 304 305 // save cache file 306 io_saveFile($file, $content); 307 if (DOKU_HAS_GZIP) io_saveFile("$file.gz", $content); 308 309 // finally send output 310 if ($conf['gzip_output'] && DOKU_HAS_GZIP) { 311 header('Vary: Accept-Encoding'); 312 header('Content-Encoding: gzip'); 313 echo gzencode($content, 9, FORCE_GZIP); 314 } else { 315 echo $content; 316 } 317} 318 319/** 320 * Fetches raw, unparsed POST data 321 * 322 * @return string 323 */ 324function http_get_raw_post_data() 325{ 326 static $postData = null; 327 if ($postData === null) { 328 $postData = file_get_contents('php://input'); 329 } 330 return $postData; 331} 332 333/** 334 * Set the HTTP response status and takes care of the used PHP SAPI 335 * 336 * Inspired by CodeIgniter's set_status_header function 337 * 338 * @param int $code 339 * @param string $text 340 */ 341function http_status($code = 200, $text = '') 342{ 343 global $INPUT; 344 345 static $stati = [ 346 200 => 'OK', 347 201 => 'Created', 348 202 => 'Accepted', 349 203 => 'Non-Authoritative Information', 350 204 => 'No Content', 351 205 => 'Reset Content', 352 206 => 'Partial Content', 353 300 => 'Multiple Choices', 354 301 => 'Moved Permanently', 355 302 => 'Found', 356 304 => 'Not Modified', 357 305 => 'Use Proxy', 358 307 => 'Temporary Redirect', 359 400 => 'Bad Request', 360 401 => 'Unauthorized', 361 403 => 'Forbidden', 362 404 => 'Not Found', 363 405 => 'Method Not Allowed', 364 406 => 'Not Acceptable', 365 407 => 'Proxy Authentication Required', 366 408 => 'Request Timeout', 367 409 => 'Conflict', 368 410 => 'Gone', 369 411 => 'Length Required', 370 412 => 'Precondition Failed', 371 413 => 'Request Entity Too Large', 372 414 => 'Request-URI Too Long', 373 415 => 'Unsupported Media Type', 374 416 => 'Requested Range Not Satisfiable', 375 417 => 'Expectation Failed', 376 500 => 'Internal Server Error', 377 501 => 'Not Implemented', 378 502 => 'Bad Gateway', 379 503 => 'Service Unavailable', 380 504 => 'Gateway Timeout', 381 505 => 'HTTP Version Not Supported' 382 ]; 383 384 if ($text == '' && isset($stati[$code])) { 385 $text = $stati[$code]; 386 } 387 388 $server_protocol = $INPUT->server->str('SERVER_PROTOCOL', false); 389 390 if (str_starts_with(PHP_SAPI, 'cgi') || defined('SIMPLE_TEST')) { 391 header("Status: {$code} {$text}", true); 392 } elseif ($server_protocol == 'HTTP/1.1' || $server_protocol == 'HTTP/1.0') { 393 header($server_protocol . " {$code} {$text}", true, $code); 394 } else { 395 header("HTTP/1.1 {$code} {$text}", true, $code); 396 } 397} 398