[Summary view]

   1  <?php
   2  
   3  /**
   4   * Licensed to Jasig under one or more contributor license
   5   * agreements. See the NOTICE file distributed with this work for
   6   * additional information regarding copyright ownership.
   7   *
   8   * Jasig licenses this file to you under the Apache License,
   9   * Version 2.0 (the "License"); you may not use this file except in
  10   * compliance with the License. You may obtain a copy of the License at:
  11   *
  12   * http://www.apache.org/licenses/LICENSE-2.0
  13   *
  14   * Unless required by applicable law or agreed to in writing, software
  15   * distributed under the License is distributed on an "AS IS" BASIS,
  16   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  17   * See the License for the specific language governing permissions and
  18   * limitations under the License.
  19   *
  20   * PHP Version 7
  21   *
  22   * @file     CAS/ProxyChain.php
  23   * @category Authentication
  24   * @package  PhpCAS
  25   * @author   Adam Franco <afranco@middlebury.edu>
  26   * @license  http://www.apache.org/licenses/LICENSE-2.0  Apache License 2.0
  27   * @link     https://wiki.jasig.org/display/CASC/phpCAS
  28   */
  29  
  30  /**
  31   * A normal proxy-chain definition that lists each level of the chain as either
  32   * a string or regular expression.
  33   *
  34   * @class    CAS_ProxyChain
  35   * @category Authentication
  36   * @package  PhpCAS
  37   * @author   Adam Franco <afranco@middlebury.edu>
  38   * @license  http://www.apache.org/licenses/LICENSE-2.0  Apache License 2.0
  39   * @link     https://wiki.jasig.org/display/CASC/phpCAS
  40   */
  41  
  42  class CAS_ProxyChain
  43  implements CAS_ProxyChain_Interface
  44  {
  45  
  46      protected $chain = array();
  47  
  48      /**
  49       * A chain is an array of strings or regexp strings that will be matched
  50       * against. Regexp will be matched with preg_match and strings will be
  51       * matched from the beginning. A string must fully match the beginning of
  52       * an proxy url. So you can define a full domain as acceptable or go further
  53       * down.
  54       * Proxies have to be defined in reverse from the service to the user. If a
  55       * user hits service A get proxied via B to service C the list of acceptable
  56       * proxies on C would be array(B,A);
  57       *
  58       * @param array $chain A chain of proxies
  59       */
  60      public function __construct(array $chain)
  61      {
  62          // Ensure that we have an indexed array
  63          $this->chain = array_values($chain);
  64      }
  65  
  66      /**
  67       * Match a list of proxies.
  68       *
  69       * @param array $list The list of proxies in front of this service.
  70       *
  71       * @return bool
  72       */
  73      public function matches(array $list)
  74      {
  75          $list = array_values($list);  // Ensure that we have an indexed array
  76          if ($this->isSizeValid($list)) {
  77              $mismatch = false;
  78              foreach ($this->chain as $i => $search) {
  79                  $proxy_url = $list[$i];
  80                  if (preg_match('/^\/.*\/[ixASUXu]*$/s', $search)) {
  81                      if (preg_match($search, $proxy_url)) {
  82                          phpCAS::trace(
  83                              "Found regexp " .  $search . " matching " . $proxy_url
  84                          );
  85                      } else {
  86                          phpCAS::trace(
  87                              "No regexp match " .  $search . " != " . $proxy_url
  88                          );
  89                          $mismatch = true;
  90                          break;
  91                      }
  92                  } else {
  93                      if (strncasecmp($search, $proxy_url, strlen($search)) == 0) {
  94                          phpCAS::trace(
  95                              "Found string " .  $search . " matching " . $proxy_url
  96                          );
  97                      } else {
  98                          phpCAS::trace(
  99                              "No match " .  $search . " != " . $proxy_url
 100                          );
 101                          $mismatch = true;
 102                          break;
 103                      }
 104                  }
 105              }
 106              if (!$mismatch) {
 107                  phpCAS::trace("Proxy chain matches");
 108                  return true;
 109              }
 110          } else {
 111              phpCAS::trace("Proxy chain skipped: size mismatch");
 112          }
 113          return false;
 114      }
 115  
 116      /**
 117       * Validate the size of the the list as compared to our chain.
 118       *
 119       * @param array $list List of proxies
 120       *
 121       * @return bool
 122       */
 123      protected function isSizeValid (array $list)
 124      {
 125          return (sizeof($this->chain) == sizeof($list));
 126      }
 127  }