src/Util/Network.php

   1 <?php
   2 /**
   3  * @file src/Util/Network.php
   4  */
   5 namespace Friendica\Util;
   6
   7 use Friendica\App;
   8 use Friendica\Core\Addon;
   9 use Friendica\Core\L10n;
  10 use Friendica\Core\System;
  11 use Friendica\Core\Config;
  12 use Friendica\Network\Probe;
  13 use Friendica\Object\Image;
  14 use Friendica\Util\XML;
  15 use DOMDocument;
  16 use DomXPath;
  17
  18 require_once 'library/slinky.php';
  19
  20 class Network
  21 {
  22         /**
  23          * @brief Curl wrapper
  24          *
  25          * If binary flag is true, return binary results.
  26          * Set the cookiejar argument to a string (e.g. "/tmp/friendica-cookies.txt")
  27          * to preserve cookies from one request to the next.
  28          *
  29          * @param string  $url            URL to fetch
  30          * @param boolean $binary         default false
  31          *                                TRUE if asked to return binary results (file download)
  32          * @param integer $redirects      The recursion counter for internal use - default 0
  33          * @param integer $timeout        Timeout in seconds, default system config value or 60 seconds
  34          * @param string  $accept_content supply Accept: header with 'accept_content' as the value
  35          * @param string  $cookiejar      Path to cookie jar file
  36          *
  37          * @return string The fetched content
  38          */
  39         public static function fetchUrl($url, $binary = false, &$redirects = 0, $timeout = 0, $accept_content = null, $cookiejar = 0)
  40         {
  41                 $ret = self::curl(
  42                         $url,
  43                         $binary,
  44                         $redirects,
  45                         ['timeout'=>$timeout,
  46                         'accept_content'=>$accept_content,
  47                         'cookiejar'=>$cookiejar
  48                         ]
  49                 );
  50
  51                 return($ret['body']);
  52         }
  53
  54         /**
  55          * @brief fetches an URL.
  56          *
  57          * @param string  $url       URL to fetch
  58          * @param boolean $binary    default false
  59          *                           TRUE if asked to return binary results (file download)
  60          * @param int     $redirects The recursion counter for internal use - default 0
  61          * @param array   $opts      (optional parameters) assoziative array with:
  62          *                           'accept_content' => supply Accept: header with 'accept_content' as the value
  63          *                           'timeout' => int Timeout in seconds, default system config value or 60 seconds
  64          *                           'http_auth' => username:password
  65          *                           'novalidate' => do not validate SSL certs, default is to validate using our CA list
  66          *                           'nobody' => only return the header
  67          *                           'cookiejar' => path to cookie jar file
  68          *
  69          * @return array an assoziative array with:
  70          *    int 'return_code' => HTTP return code or 0 if timeout or failure
  71          *    boolean 'success' => boolean true (if HTTP 2xx result) or false
  72          *    string 'redirect_url' => in case of redirect, content was finally retrieved from this URL
  73          *    string 'header' => HTTP headers
  74          *    string 'body' => fetched content
  75          */
  76         public static function curl($url, $binary = false, &$redirects = 0, $opts = [])
  77         {
  78                 $ret = ['return_code' => 0, 'success' => false, 'header' => '', 'info' => '', 'body' => ''];
  79
  80                 $stamp1 = microtime(true);
  81
  82                 $a = get_app();
  83
  84                 if (self::isUrlBlocked($url)) {
  85                         logger('z_fetch_url: domain of ' . $url . ' is blocked', LOGGER_DATA);
  86                         return $ret;
  87                 }
  88
  89                 $ch = @curl_init($url);
  90
  91                 if (($redirects > 8) || (!$ch)) {
  92                         return $ret;
  93                 }
  94
  95                 @curl_setopt($ch, CURLOPT_HEADER, true);
  96
  97                 if (x($opts, "cookiejar")) {
  98                         curl_setopt($ch, CURLOPT_COOKIEJAR, $opts["cookiejar"]);
  99                         curl_setopt($ch, CURLOPT_COOKIEFILE, $opts["cookiejar"]);
 100                 }
 101
 102                 // These settings aren't needed. We're following the location already.
 103                 //      @curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
 104                 //      @curl_setopt($ch, CURLOPT_MAXREDIRS, 5);
 105
 106                 if (x($opts, 'accept_content')) {
 107                         curl_setopt(
 108                                 $ch,
 109                                 CURLOPT_HTTPHEADER,
 110                                 ['Accept: ' . $opts['accept_content']]
 111                         );
 112                 }
 113
 114                 @curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
 115                 @curl_setopt($ch, CURLOPT_USERAGENT, $a->get_useragent());
 116
 117                 $range = intval(Config::get('system', 'curl_range_bytes', 0));
 118
 119                 if ($range > 0) {
 120                         @curl_setopt($ch, CURLOPT_RANGE, '0-' . $range);
 121                 }
 122
 123                 // Without this setting it seems as if some webservers send compressed content
 124                 // This seems to confuse curl so that it shows this uncompressed.
 125                 /// @todo  We could possibly set this value to "gzip" or something similar
 126                 curl_setopt($ch, CURLOPT_ENCODING, '');
 127
 128                 if (x($opts, 'headers')) {
 129                         @curl_setopt($ch, CURLOPT_HTTPHEADER, $opts['headers']);
 130                 }
 131
 132                 if (x($opts, 'nobody')) {
 133                         @curl_setopt($ch, CURLOPT_NOBODY, $opts['nobody']);
 134                 }
 135
 136                 if (x($opts, 'timeout')) {
 137                         @curl_setopt($ch, CURLOPT_TIMEOUT, $opts['timeout']);
 138                 } else {
 139                         $curl_time = Config::get('system', 'curl_timeout', 60);
 140                         @curl_setopt($ch, CURLOPT_TIMEOUT, intval($curl_time));
 141                 }
 142
 143                 // by default we will allow self-signed certs
 144                 // but you can override this
 145
 146                 $check_cert = Config::get('system', 'verifyssl');
 147                 @curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, (($check_cert) ? true : false));
 148
 149                 if ($check_cert) {
 150                         @curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 2);
 151                 }
 152
 153                 $proxy = Config::get('system', 'proxy');
 154
 155                 if (strlen($proxy)) {
 156                         @curl_setopt($ch, CURLOPT_HTTPPROXYTUNNEL, 1);
 157                         @curl_setopt($ch, CURLOPT_PROXY, $proxy);
 158                         $proxyuser = @Config::get('system', 'proxyuser');
 159
 160                         if (strlen($proxyuser)) {
 161                                 @curl_setopt($ch, CURLOPT_PROXYUSERPWD, $proxyuser);
 162                         }
 163                 }
 164
 165                 if (Config::get('system', 'ipv4_resolve', false)) {
 166                         curl_setopt($ch, CURLOPT_IPRESOLVE, CURL_IPRESOLVE_V4);
 167                 }
 168
 169                 if ($binary) {
 170                         @curl_setopt($ch, CURLOPT_BINARYTRANSFER, 1);
 171                 }
 172
 173                 $a->set_curl_code(0);
 174
 175                 // don't let curl abort the entire application
 176                 // if it throws any errors.
 177
 178                 $s = @curl_exec($ch);
 179                 $curl_info = @curl_getinfo($ch);
 180
 181                 // Special treatment for HTTP Code 416
 182                 // See https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/416
 183                 if (($curl_info['http_code'] == 416) && ($range > 0)) {
 184                         @curl_setopt($ch, CURLOPT_RANGE, '');
 185                         $s = @curl_exec($ch);
 186                         $curl_info = @curl_getinfo($ch);
 187                 }
 188
 189                 if (curl_errno($ch) !== CURLE_OK) {
 190                         logger('fetch_url error fetching ' . $url . ': ' . curl_error($ch), LOGGER_NORMAL);
 191                 }
 192
 193                 $ret['errno'] = curl_errno($ch);
 194
 195                 $base = $s;
 196                 $ret['info'] = $curl_info;
 197
 198                 $http_code = $curl_info['http_code'];
 199
 200                 logger('fetch_url ' . $url . ': ' . $http_code . " " . $s, LOGGER_DATA);
 201                 $header = '';
 202
 203                 // Pull out multiple headers, e.g. proxy and continuation headers
 204                 // allow for HTTP/2.x without fixing code
 205
 206                 while (preg_match('/^HTTP\/[1-2].+? [1-5][0-9][0-9]/', $base)) {
 207                         $chunk = substr($base, 0, strpos($base, "\r\n\r\n") + 4);
 208                         $header .= $chunk;
 209                         $base = substr($base, strlen($chunk));
 210                 }
 211
 212                 $a->set_curl_code($http_code);
 213                 $a->set_curl_content_type($curl_info['content_type']);
 214                 $a->set_curl_headers($header);
 215
 216                 if ($http_code == 301 || $http_code == 302 || $http_code == 303 || $http_code == 307) {
 217                         $new_location_info = @parse_url($curl_info['redirect_url']);
 218                         $old_location_info = @parse_url($curl_info['url']);
 219
 220                         $newurl = $curl_info['redirect_url'];
 221
 222                         if (($new_location_info['path'] == '') && ( $new_location_info['host'] != '')) {
 223                                 $newurl = $new_location_info['scheme'] . '://' . $new_location_info['host'] . $old_location_info['path'];
 224                         }
 225
 226                         $matches = [];
 227
 228                         if (preg_match('/(Location:|URI:)(.*?)\n/i', $header, $matches)) {
 229                                 $newurl = trim(array_pop($matches));
 230                         }
 231                         if (strpos($newurl, '/') === 0) {
 232                                 $newurl = $old_location_info["scheme"]."://".$old_location_info["host"].$newurl;
 233                         }
 234
 235                         if (filter_var($newurl, FILTER_VALIDATE_URL)) {
 236                                 $redirects++;
 237                                 @curl_close($ch);
 238                                 return self::curl($newurl, $binary, $redirects, $opts);
 239                         }
 240                 }
 241
 242                 $a->set_curl_code($http_code);
 243                 $a->set_curl_content_type($curl_info['content_type']);
 244
 245                 $rc = intval($http_code);
 246                 $ret['return_code'] = $rc;
 247                 $ret['success'] = (($rc >= 200 && $rc <= 299) ? true : false);
 248                 $ret['redirect_url'] = $url;
 249
 250                 if (!$ret['success']) {
 251                         $ret['error'] = curl_error($ch);
 252                         $ret['debug'] = $curl_info;
 253                         logger('z_fetch_url: error: '.$url.': '.$ret['return_code'].' - '.$ret['error'], LOGGER_DEBUG);
 254                         logger('z_fetch_url: debug: '.print_r($curl_info, true), LOGGER_DATA);
 255                 }
 256
 257                 $ret['body'] = substr($s, strlen($header));
 258                 $ret['header'] = $header;
 259
 260                 if (x($opts, 'debug')) {
 261                         $ret['debug'] = $curl_info;
 262                 }
 263
 264                 @curl_close($ch);
 265
 266                 $a->save_timestamp($stamp1, 'network');
 267
 268                 return($ret);
 269         }
 270
 271         /**
 272          * @brief Send POST request to $url
 273          *
 274          * @param string  $url       URL to post
 275          * @param mixed   $params    array of POST variables
 276          * @param string  $headers   HTTP headers
 277          * @param integer $redirects Recursion counter for internal use - default = 0
 278          * @param integer $timeout   The timeout in seconds, default system config value or 60 seconds
 279          *
 280          * @return string The content
 281          */
 282         public static function post($url, $params, $headers = null, &$redirects = 0, $timeout = 0)
 283         {
 284                 $stamp1 = microtime(true);
 285
 286                 if (self::isUrlBlocked($url)) {
 287                         logger('post_url: domain of ' . $url . ' is blocked', LOGGER_DATA);
 288                         return false;
 289                 }
 290
 291                 $a = get_app();
 292                 $ch = curl_init($url);
 293
 294                 if (($redirects > 8) || (!$ch)) {
 295                         return false;
 296                 }
 297
 298                 logger('post_url: start ' . $url, LOGGER_DATA);
 299
 300                 curl_setopt($ch, CURLOPT_HEADER, true);
 301                 curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
 302                 curl_setopt($ch, CURLOPT_POST, 1);
 303                 curl_setopt($ch, CURLOPT_POSTFIELDS, $params);
 304                 curl_setopt($ch, CURLOPT_USERAGENT, $a->get_useragent());
 305
 306                 if (Config::get('system', 'ipv4_resolve', false)) {
 307                         curl_setopt($ch, CURLOPT_IPRESOLVE, CURL_IPRESOLVE_V4);
 308                 }
 309
 310                 if (intval($timeout)) {
 311                         curl_setopt($ch, CURLOPT_TIMEOUT, $timeout);
 312                 } else {
 313                         $curl_time = Config::get('system', 'curl_timeout', 60);
 314                         curl_setopt($ch, CURLOPT_TIMEOUT, intval($curl_time));
 315                 }
 316
 317                 if (defined('LIGHTTPD')) {
 318                         if (!is_array($headers)) {
 319                                 $headers = ['Expect:'];
 320                         } else {
 321                                 if (!in_array('Expect:', $headers)) {
 322                                         array_push($headers, 'Expect:');
 323                                 }
 324                         }
 325                 }
 326
 327                 if ($headers) {
 328                         curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
 329                 }
 330
 331                 $check_cert = Config::get('system', 'verifyssl');
 332                 curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, (($check_cert) ? true : false));
 333
 334                 if ($check_cert) {
 335                         @curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 2);
 336                 }
 337
 338                 $proxy = Config::get('system', 'proxy');
 339
 340                 if (strlen($proxy)) {
 341                         curl_setopt($ch, CURLOPT_HTTPPROXYTUNNEL, 1);
 342                         curl_setopt($ch, CURLOPT_PROXY, $proxy);
 343                         $proxyuser = Config::get('system', 'proxyuser');
 344                         if (strlen($proxyuser)) {
 345                                 curl_setopt($ch, CURLOPT_PROXYUSERPWD, $proxyuser);
 346                         }
 347                 }
 348
 349                 $a->set_curl_code(0);
 350
 351                 // don't let curl abort the entire application
 352                 // if it throws any errors.
 353
 354                 $s = @curl_exec($ch);
 355
 356                 $base = $s;
 357                 $curl_info = curl_getinfo($ch);
 358                 $http_code = $curl_info['http_code'];
 359
 360                 logger('post_url: result ' . $http_code . ' - ' . $url, LOGGER_DATA);
 361
 362                 $header = '';
 363
 364                 // Pull out multiple headers, e.g. proxy and continuation headers
 365                 // allow for HTTP/2.x without fixing code
 366
 367                 while (preg_match('/^HTTP\/[1-2].+? [1-5][0-9][0-9]/', $base)) {
 368                         $chunk = substr($base, 0, strpos($base, "\r\n\r\n") + 4);
 369                         $header .= $chunk;
 370                         $base = substr($base, strlen($chunk));
 371                 }
 372
 373                 if ($http_code == 301 || $http_code == 302 || $http_code == 303 || $http_code == 307) {
 374                         $matches = [];
 375                         preg_match('/(Location:|URI:)(.*?)\n/', $header, $matches);
 376                         $newurl = trim(array_pop($matches));
 377
 378                         if (strpos($newurl, '/') === 0) {
 379                                 $newurl = $old_location_info["scheme"] . "://" . $old_location_info["host"] . $newurl;
 380                         }
 381
 382                         if (filter_var($newurl, FILTER_VALIDATE_URL)) {
 383                                 $redirects++;
 384                                 logger('post_url: redirect ' . $url . ' to ' . $newurl);
 385                                 return self::post($newurl, $params, $headers, $redirects, $timeout);
 386                         }
 387                 }
 388
 389                 $a->set_curl_code($http_code);
 390
 391                 $body = substr($s, strlen($header));
 392
 393                 $a->set_curl_headers($header);
 394
 395                 curl_close($ch);
 396
 397                 $a->save_timestamp($stamp1, 'network');
 398
 399                 logger('post_url: end ' . $url, LOGGER_DATA);
 400
 401                 return $body;
 402         }
 403
 404         /**
 405          * @brief Check URL to see if it's real
 406          *
 407          * Take a URL from the wild, prepend http:// if necessary
 408          * and check DNS to see if it's real (or check if is a valid IP address)
 409          *
 410          * @param string $url The URL to be validated
 411          * @return string|boolean The actual working URL, false else
 412          */
 413         public static function isUrlValid($url)
 414         {
 415                 if (Config::get('system', 'disable_url_validation')) {
 416                         return $url;
 417                 }
 418
 419                 // no naked subdomains (allow localhost for tests)
 420                 if (strpos($url, '.') === false && strpos($url, '/localhost/') === false) {
 421                         return false;
 422                 }
 423
 424                 if (substr($url, 0, 4) != 'http') {
 425                         $url = 'http://' . $url;
 426                 }
 427
 428                 /// @TODO Really suppress function outcomes? Why not find them + debug them?
 429                 $h = @parse_url($url);
 430
 431                 if ((is_array($h)) && (@dns_get_record($h['host'], DNS_A + DNS_CNAME + DNS_PTR) || filter_var($h['host'], FILTER_VALIDATE_IP) )) {
 432                         return $url;
 433                 }
 434
 435                 return false;
 436         }
 437
 438         /**
 439          * @brief Checks that email is an actual resolvable internet address
 440          *
 441          * @param string $addr The email address
 442          * @return boolean True if it's a valid email address, false if it's not
 443          */
 444         public static function isEmailDomainValid($addr)
 445         {
 446                 if (Config::get('system', 'disable_email_validation')) {
 447                         return true;
 448                 }
 449
 450                 if (! strpos($addr, '@')) {
 451                         return false;
 452                 }
 453
 454                 $h = substr($addr, strpos($addr, '@') + 1);
 455
 456                 if (($h) && (dns_get_record($h, DNS_A + DNS_CNAME + DNS_PTR + DNS_MX) || filter_var($h, FILTER_VALIDATE_IP) )) {
 457                         return true;
 458                 }
 459                 return false;
 460         }
 461
 462         /**
 463          * @brief Check if URL is allowed
 464          *
 465          * Check $url against our list of allowed sites,
 466          * wildcards allowed. If allowed_sites is unset return true;
 467          *
 468          * @param string $url URL which get tested
 469          * @return boolean True if url is allowed otherwise return false
 470          */
 471         public static function isUrlAllowed($url)
 472         {
 473                 $h = @parse_url($url);
 474
 475                 if (! $h) {
 476                         return false;
 477                 }
 478
 479                 $str_allowed = Config::get('system', 'allowed_sites');
 480                 if (! $str_allowed) {
 481                         return true;
 482                 }
 483
 484                 $found = false;
 485
 486                 $host = strtolower($h['host']);
 487
 488                 // always allow our own site
 489                 if ($host == strtolower($_SERVER['SERVER_NAME'])) {
 490                         return true;
 491                 }
 492
 493                 $fnmatch = function_exists('fnmatch');
 494                 $allowed = explode(',', $str_allowed);
 495
 496                 if (count($allowed)) {
 497                         foreach ($allowed as $a) {
 498                                 $pat = strtolower(trim($a));
 499                                 if (($fnmatch && fnmatch($pat, $host)) || ($pat == $host)) {
 500                                         $found = true;
 501                                         break;
 502                                 }
 503                         }
 504                 }
 505                 return $found;
 506         }
 507
 508         /**
 509          * Checks if the provided url domain is on the domain blocklist.
 510          * Returns true if it is or malformed URL, false if not.
 511          *
 512          * @param string $url The url to check the domain from
 513          *
 514          * @return boolean
 515          */
 516         public static function isUrlBlocked($url)
 517         {
 518                 $h = @parse_url($url);
 519
 520                 if (! $h) {
 521                         return true;
 522                 }
 523
 524                 $domain_blocklist = Config::get('system', 'blocklist', []);
 525                 if (! $domain_blocklist) {
 526                         return false;
 527                 }
 528
 529                 $host = strtolower($h['host']);
 530
 531                 foreach ($domain_blocklist as $domain_block) {
 532                         if (strtolower($domain_block['domain']) == $host) {
 533                                 return true;
 534                         }
 535                 }
 536
 537                 return false;
 538         }
 539
 540         /**
 541          * @brief Check if email address is allowed to register here.
 542          *
 543          * Compare against our list (wildcards allowed).
 544          *
 545          * @param  string $email email address
 546          * @return boolean False if not allowed, true if allowed
 547          *    or if allowed list is not configured
 548          */
 549         public static function isEmailDomainAllowed($email)
 550         {
 551                 $domain = strtolower(substr($email, strpos($email, '@') + 1));
 552                 if (!$domain) {
 553                         return false;
 554                 }
 555
 556                 $str_allowed = Config::get('system', 'allowed_email', '');
 557                 if (!x($str_allowed)) {
 558                         return true;
 559                 }
 560
 561                 $allowed = explode(',', $str_allowed);
 562
 563                 return self::isDomainAllowed($domain, $allowed);
 564         }
 565
 566         /**
 567          * Checks for the existence of a domain in a domain list
 568          *
 569          * @brief Checks for the existence of a domain in a domain list
 570          * @param string $domain
 571          * @param array  $domain_list
 572          * @return boolean
 573          */
 574         public static function isDomainAllowed($domain, array $domain_list)
 575         {
 576                 $found = false;
 577
 578                 foreach ($domain_list as $item) {
 579                         $pat = strtolower(trim($item));
 580                         if (fnmatch($pat, $domain) || ($pat == $domain)) {
 581                                 $found = true;
 582                                 break;
 583                         }
 584                 }
 585
 586                 return $found;
 587         }
 588
 589         public static function lookupAvatarByEmail($email)
 590         {
 591                 $avatar['size'] = 175;
 592                 $avatar['email'] = $email;
 593                 $avatar['url'] = '';
 594                 $avatar['success'] = false;
 595
 596                 Addon::callHooks('avatar_lookup', $avatar);
 597
 598                 if (! $avatar['success']) {
 599                         $avatar['url'] = System::baseUrl() . '/images/person-175.jpg';
 600                 }
 601
 602                 logger('Avatar: ' . $avatar['email'] . ' ' . $avatar['url'], LOGGER_DEBUG);
 603                 return $avatar['url'];
 604         }
 605
 606         /**
 607          * @brief Remove Google Analytics and other tracking platforms params from URL
 608          *
 609          * @param string $url Any user-submitted URL that may contain tracking params
 610          * @return string The same URL stripped of tracking parameters
 611          */
 612         public static function stripTrackingQueryParams($url)
 613         {
 614                 $urldata = parse_url($url);
 615                 if (is_string($urldata["query"])) {
 616                         $query = $urldata["query"];
 617                         parse_str($query, $querydata);
 618
 619                         if (is_array($querydata)) {
 620                                 foreach ($querydata as $param => $value) {
 621                                         if (in_array(
 622                                                 $param,
 623                                                 [
 624                                                         "utm_source", "utm_medium", "utm_term", "utm_content", "utm_campaign",
 625                                                         "wt_mc", "pk_campaign", "pk_kwd", "mc_cid", "mc_eid",
 626                                                         "fb_action_ids", "fb_action_types", "fb_ref",
 627                                                         "awesm", "wtrid",
 628                                                         "woo_campaign", "woo_source", "woo_medium", "woo_content", "woo_term"]
 629                                                 )
 630                                         ) {
 631                                                 $pair = $param . "=" . urlencode($value);
 632                                                 $url = str_replace($pair, "", $url);
 633
 634                                                 // Second try: if the url isn't encoded completely
 635                                                 $pair = $param . "=" . str_replace(" ", "+", $value);
 636                                                 $url = str_replace($pair, "", $url);
 637
 638                                                 // Third try: Maybey the url isn't encoded at all
 639                                                 $pair = $param . "=" . $value;
 640                                                 $url = str_replace($pair, "", $url);
 641
 642                                                 $url = str_replace(["?&", "&&"], ["?", ""], $url);
 643                                         }
 644                                 }
 645                         }
 646
 647                         if (substr($url, -1, 1) == "?") {
 648                                 $url = substr($url, 0, -1);
 649                         }
 650                 }
 651
 652                 return $url;
 653         }
 654
 655         /**
 656          * @brief Returns the original URL of the provided URL
 657          *
 658          * This function strips tracking query params and follows redirections, either
 659          * through HTTP code or meta refresh tags. Stops after 10 redirections.
 660          *
 661          * @todo Remove the $fetchbody parameter that generates an extraneous HEAD request
 662          *
 663          * @see ParseUrl::getSiteinfo
 664          *
 665          * @param string $url       A user-submitted URL
 666          * @param int    $depth     The current redirection recursion level (internal)
 667          * @param bool   $fetchbody Wether to fetch the body or not after the HEAD requests
 668          * @return string A canonical URL
 669          */
 670         public static function finalUrl($url, $depth = 1, $fetchbody = false)
 671         {
 672                 $a = get_app();
 673
 674                 $url = self::stripTrackingQueryParams($url);
 675
 676                 if ($depth > 10) {
 677                         return($url);
 678                 }
 679
 680                 $url = trim($url, "'");
 681
 682                 $stamp1 = microtime(true);
 683
 684                 $ch = curl_init();
 685                 curl_setopt($ch, CURLOPT_URL, $url);
 686                 curl_setopt($ch, CURLOPT_HEADER, 1);
 687                 curl_setopt($ch, CURLOPT_NOBODY, 1);
 688                 curl_setopt($ch, CURLOPT_TIMEOUT, 10);
 689                 curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
 690                 curl_setopt($ch, CURLOPT_USERAGENT, $a->get_useragent());
 691
 692                 curl_exec($ch);
 693                 $curl_info = @curl_getinfo($ch);
 694                 $http_code = $curl_info['http_code'];
 695                 curl_close($ch);
 696
 697                 $a->save_timestamp($stamp1, "network");
 698
 699                 if ($http_code == 0) {
 700                         return($url);
 701                 }
 702
 703                 if ((($curl_info['http_code'] == "301") || ($curl_info['http_code'] == "302"))
 704                         && (($curl_info['redirect_url'] != "") || ($curl_info['location'] != ""))
 705                 ) {
 706                         if ($curl_info['redirect_url'] != "") {
 707                                 return(self::finalUrl($curl_info['redirect_url'], ++$depth, $fetchbody));
 708                         } else {
 709                                 return(self::finalUrl($curl_info['location'], ++$depth, $fetchbody));
 710                         }
 711                 }
 712
 713                 // Check for redirects in the meta elements of the body if there are no redirects in the header.
 714                 if (!$fetchbody) {
 715                         return(self::finalUrl($url, ++$depth, true));
 716                 }
 717
 718                 // if the file is too large then exit
 719                 if ($curl_info["download_content_length"] > 1000000) {
 720                         return($url);
 721                 }
 722
 723                 // if it isn't a HTML file then exit
 724                 if (($curl_info["content_type"] != "") && !strstr(strtolower($curl_info["content_type"]), "html")) {
 725                         return($url);
 726                 }
 727
 728                 $stamp1 = microtime(true);
 729
 730                 $ch = curl_init();
 731                 curl_setopt($ch, CURLOPT_URL, $url);
 732                 curl_setopt($ch, CURLOPT_HEADER, 0);
 733                 curl_setopt($ch, CURLOPT_NOBODY, 0);
 734                 curl_setopt($ch, CURLOPT_TIMEOUT, 10);
 735                 curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
 736                 curl_setopt($ch, CURLOPT_USERAGENT, $a->get_useragent());
 737
 738                 $body = curl_exec($ch);
 739                 curl_close($ch);
 740
 741                 $a->save_timestamp($stamp1, "network");
 742
 743                 if (trim($body) == "") {
 744                         return($url);
 745                 }
 746
 747                 // Check for redirect in meta elements
 748                 $doc = new DOMDocument();
 749                 @$doc->loadHTML($body);
 750
 751                 $xpath = new DomXPath($doc);
 752
 753                 $list = $xpath->query("//meta[@content]");
 754                 foreach ($list as $node) {
 755                         $attr = [];
 756                         if ($node->attributes->length) {
 757                                 foreach ($node->attributes as $attribute) {
 758                                         $attr[$attribute->name] = $attribute->value;
 759                                 }
 760                         }
 761
 762                         if (@$attr["http-equiv"] == 'refresh') {
 763                                 $path = $attr["content"];
 764                                 $pathinfo = explode(";", $path);
 765                                 foreach ($pathinfo as $value) {
 766                                         if (substr(strtolower($value), 0, 4) == "url=") {
 767                                                 return(self::finalUrl(substr($value, 4), ++$depth));
 768                                         }
 769                                 }
 770                         }
 771                 }
 772
 773                 return $url;
 774         }
 775
 776         public static function shortenUrl($url)
 777         {
 778                 $slinky = new Slinky($url);
 779                 $yourls_url = Config::get('yourls', 'url1');
 780                 if ($yourls_url) {
 781                         $yourls_username = Config::get('yourls', 'username1');
 782                         $yourls_password = Config::get('yourls', 'password1');
 783                         $yourls_ssl = Config::get('yourls', 'ssl1');
 784                         $yourls = new Slinky_YourLS();
 785                         $yourls->set('username', $yourls_username);
 786                         $yourls->set('password', $yourls_password);
 787                         $yourls->set('ssl', $yourls_ssl);
 788                         $yourls->set('yourls-url', $yourls_url);
 789                         $slinky->set_cascade([$yourls, new Slinky_Ur1ca(), new Slinky_TinyURL()]);
 790                 } else {
 791                         // setup a cascade of shortening services
 792                         // try to get a short link from these services
 793                         // in the order ur1.ca, tinyurl
 794                         $slinky->set_cascade([new Slinky_Ur1ca(), new Slinky_TinyURL()]);
 795                 }
 796                 return $slinky->short();
 797         }
 798
 799         /**
 800          * @brief Find the matching part between two url
 801          *
 802          * @param string $url1
 803          * @param string $url2
 804          * @return string The matching part
 805          */
 806         public static function getUrlMatch($url1, $url2)
 807         {
 808                 if (($url1 == "") || ($url2 == "")) {
 809                         return "";
 810                 }
 811
 812                 $url1 = normalise_link($url1);
 813                 $url2 = normalise_link($url2);
 814
 815                 $parts1 = parse_url($url1);
 816                 $parts2 = parse_url($url2);
 817
 818                 if (!isset($parts1["host"]) || !isset($parts2["host"])) {
 819                         return "";
 820                 }
 821
 822                 if ($parts1["scheme"] != $parts2["scheme"]) {
 823                         return "";
 824                 }
 825
 826                 if ($parts1["host"] != $parts2["host"]) {
 827                         return "";
 828                 }
 829
 830                 if ($parts1["port"] != $parts2["port"]) {
 831                         return "";
 832                 }
 833
 834                 $match = $parts1["scheme"]."://".$parts1["host"];
 835
 836                 if ($parts1["port"]) {
 837                         $match .= ":".$parts1["port"];
 838                 }
 839
 840                 $pathparts1 = explode("/", $parts1["path"]);
 841                 $pathparts2 = explode("/", $parts2["path"]);
 842
 843                 $i = 0;
 844                 $path = "";
 845                 do {
 846                         $path1 = $pathparts1[$i];
 847                         $path2 = $pathparts2[$i];
 848
 849                         if ($path1 == $path2) {
 850                                 $path .= $path1."/";
 851                         }
 852                 } while (($path1 == $path2) && ($i++ <= count($pathparts1)));
 853
 854                 $match .= $path;
 855
 856                 return normalise_link($match);
 857         }
 858
 859         /**
 860          * @brief Glue url parts together
 861          *
 862          * @param array $parsed URL parts
 863          *
 864          * @return string The glued URL
 865          */
 866         public static function unparseURL($parsed)
 867         {
 868                 $get = function ($key) use ($parsed) {
 869                         return isset($parsed[$key]) ? $parsed[$key] : null;
 870                 };
 871
 872                 $pass      = $get('pass');
 873                 $user      = $get('user');
 874                 $userinfo  = $pass !== null ? "$user:$pass" : $user;
 875                 $port      = $get('port');
 876                 $scheme    = $get('scheme');
 877                 $query     = $get('query');
 878                 $fragment  = $get('fragment');
 879                 $authority = ($userinfo !== null ? $userinfo."@" : '') .
 880                                                 $get('host') .
 881                                                 ($port ? ":$port" : '');
 882
 883                 return  (strlen($scheme) ? $scheme.":" : '') .
 884                         (strlen($authority) ? "//".$authority : '') .
 885                         $get('path') .
 886                         (strlen($query) ? "?".$query : '') .
 887                         (strlen($fragment) ? "#".$fragment : '');
 888         }
 889 }