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Differences Between: [Versions 401 and 402] [Versions 401 and 403]

   1  <?php
   2  
   3  namespace IMSGlobal\LTI\OAuth;
   4  
   5  /**
   6   * Class to provide %OAuth utility methods
   7   *
   8   * @copyright  Andy Smith
   9   * @version 2008-08-04
  10   * @license https://opensource.org/licenses/MIT The MIT License
  11   */
  12  class OAuthUtil {
  13  
  14      public static function urlencode_rfc3986($input) {
  15  
  16          if (is_array($input)) {
  17              return array_map(array('IMSGlobal\LTI\OAuth\OAuthUtil', 'urlencode_rfc3986'), $input);
  18          } else if (is_scalar($input)) {
  19              return str_replace('+', ' ', str_replace('%7E', '~', rawurlencode($input)));
  20          } else {
  21              return '';
  22          }
  23      }
  24  
  25      // This decode function isn't taking into consideration the above
  26      // modifications to the encoding process. However, this method doesn't
  27      // seem to be used anywhere so leaving it as is.
  28      public static function urldecode_rfc3986($string) {
  29          return urldecode($string);
  30      }
  31  
  32      // Utility function for turning the Authorization: header into
  33      // parameters, has to do some unescaping
  34      // Can filter out any non-oauth parameters if needed (default behaviour)
  35      // May 28th, 2010 - method updated to tjerk.meesters for a speed improvement.
  36      //                  see http://code.google.com/p/oauth/issues/detail?id=163
  37      public static function split_header($header, $only_allow_oauth_parameters = true) {
  38  
  39          $params = array();
  40          if (preg_match_all('/('.($only_allow_oauth_parameters ? 'oauth_' : '').'[a-z_-]*)=(:?"([^"]*)"|([^,]*))/', $header, $matches)) {
  41              foreach ($matches[1] as $i => $h) {
  42                  $params[$h] = OAuthUtil::urldecode_rfc3986(empty($matches[3][$i]) ? $matches[4][$i] : $matches[3][$i]);
  43              }
  44              if (isset($params['realm'])) {
  45                  unset($params['realm']);
  46              }
  47          }
  48  
  49          return $params;
  50  
  51      }
  52  
  53      // helper to try to sort out headers for people who aren't running apache
  54      public static function get_headers() {
  55  
  56          if (function_exists('apache_request_headers')) {
  57              // we need this to get the actual Authorization: header
  58              // because apache tends to tell us it doesn't exist
  59              $headers = apache_request_headers();
  60  
  61              // sanitize the output of apache_request_headers because
  62              // we always want the keys to be Cased-Like-This and arh()
  63              // returns the headers in the same case as they are in the
  64              // request
  65              $out = array();
  66              foreach ($headers AS $key => $value) {
  67                  $key = str_replace(" ", "-", ucwords(strtolower(str_replace("-", " ", $key))));
  68                  $out[$key] = $value;
  69              }
  70          } else {
  71              // otherwise we don't have apache and are just going to have to hope
  72              // that $_SERVER actually contains what we need
  73              $out = array();
  74              if( isset($_SERVER['CONTENT_TYPE']) )
  75                  $out['Content-Type'] = $_SERVER['CONTENT_TYPE'];
  76              if( isset($_ENV['CONTENT_TYPE']) )
  77                  $out['Content-Type'] = $_ENV['CONTENT_TYPE'];
  78  
  79              foreach ($_SERVER as $key => $value) {
  80                  if (substr($key, 0, 5) == 'HTTP_') {
  81                      // this is chaos, basically it is just there to capitalize the first
  82                      // letter of every word that is not an initial HTTP and strip HTTP
  83                      // code from przemek
  84                      $key = str_replace(' ', '-', ucwords(strtolower(str_replace('_', ' ', substr($key, 5)))));
  85                      $out[$key] = $value;
  86                  }
  87              }
  88          }
  89          return $out;
  90      }
  91  
  92      // This function takes a input like a=b&a=c&d=e and returns the parsed
  93      // parameters like this
  94      // array('a' => array('b','c'), 'd' => 'e')
  95      public static function parse_parameters( $input ) {
  96  
  97          if (!isset($input) || !$input) return array();
  98  
  99          $pairs = explode('&', $input);
 100  
 101          $parsed_parameters = array();
 102          foreach ($pairs as $pair) {
 103              $split = explode('=', $pair, 2);
 104              $parameter = self::urldecode_rfc3986($split[0]);
 105              $value = isset($split[1]) ? self::urldecode_rfc3986($split[1]) : '';
 106  
 107              if (isset($parsed_parameters[$parameter])) {
 108                  // We have already recieved parameter(s) with this name, so add to the list
 109                  // of parameters with this name
 110  
 111                  if (is_scalar($parsed_parameters[$parameter])) {
 112                      // This is the first duplicate, so transform scalar (string) into an array
 113                      // so we can add the duplicates
 114                      $parsed_parameters[$parameter] = array($parsed_parameters[$parameter]);
 115                  }
 116  
 117                  $parsed_parameters[$parameter][] = $value;
 118              } else {
 119                  $parsed_parameters[$parameter] = $value;
 120              }
 121          }
 122  
 123          return $parsed_parameters;
 124  
 125      }
 126  
 127      public static function build_http_query($params) {
 128  
 129          if (!$params) return '';
 130  
 131          // Urlencode both keys and values
 132          $keys = OAuthUtil::urlencode_rfc3986(array_keys($params));
 133          $values = OAuthUtil::urlencode_rfc3986(array_values($params));
 134          $params = array_combine($keys, $values);
 135  
 136          // Parameters are sorted by name, using lexicographical byte value ordering.
 137          // Ref: Spec: 9.1.1 (1)
 138          uksort($params, 'strcmp');
 139  
 140          $pairs = array();
 141          foreach ($params as $parameter => $value) {
 142              if (is_array($value)) {
 143                  // If two or more parameters share the same name, they are sorted by their value
 144                  // Ref: Spec: 9.1.1 (1)
 145                  // June 12th, 2010 - changed to sort because of issue 164 by hidetaka
 146                  sort($value, SORT_STRING);
 147                  foreach ($value as $duplicate_value) {
 148                      $pairs[] = $parameter . '=' . $duplicate_value;
 149                  }
 150              } else {
 151                  $pairs[] = $parameter . '=' . $value;
 152              }
 153          }
 154  
 155          // For each parameter, the name is separated from the corresponding value by an '=' character (ASCII code 61)
 156          // Each name-value pair is separated by an '&' character (ASCII code 38)
 157          return implode('&', $pairs);
 158  
 159      }
 160  
 161  }