src/Util/Security.php

   1 <?php
   2 /**
   3  * @file /src/Util/Security.php
   4  */
   5
   6 namespace Friendica\Util;
   7
   8 use Friendica\BaseObject;
   9 use Friendica\Database\DBA;
  10 use Friendica\Model\Contact;
  11 use Friendica\Model\Group;
  12 use Friendica\Core\L10n;
  13 use Friendica\Model\PermissionSet;
  14 use Friendica\Core\System;
  15
  16 /**
  17  * Secures that User is allow to do requests
  18  */
  19 class Security extends BaseObject
  20 {
  21         public static function canWriteToUserWall($owner)
  22         {
  23                 static $verified = 0;
  24
  25                 if (!local_user() && !remote_user()) {
  26                         return false;
  27                 }
  28
  29                 $uid = local_user();
  30                 if ($uid == $owner) {
  31                         return true;
  32                 }
  33
  34                 if (local_user() && ($owner == 0)) {
  35                         return true;
  36                 }
  37
  38                 if (remote_user()) {
  39                         // use remembered decision and avoid a DB lookup for each and every display item
  40                         // DO NOT use this function if there are going to be multiple owners
  41                         // We have a contact-id for an authenticated remote user, this block determines if the contact
  42                         // belongs to this page owner, and has the necessary permissions to post content
  43
  44                         if ($verified === 2) {
  45                                 return true;
  46                         } elseif ($verified === 1) {
  47                                 return false;
  48                         } else {
  49                                 $cid = 0;
  50
  51                                 if (!empty($_SESSION['remote'])) {
  52                                         foreach ($_SESSION['remote'] as $visitor) {
  53                                                 if ($visitor['uid'] == $owner) {
  54                                                         $cid = $visitor['cid'];
  55                                                         break;
  56                                                 }
  57                                         }
  58                                 }
  59
  60                                 if (!$cid) {
  61                                         return false;
  62                                 }
  63
  64                                 $r = q("SELECT `contact`.*, `user`.`page-flags` FROM `contact` INNER JOIN `user` on `user`.`uid` = `contact`.`uid`
  65                                         WHERE `contact`.`uid` = %d AND `contact`.`id` = %d AND `contact`.`blocked` = 0 AND `contact`.`pending` = 0
  66                                         AND `user`.`blockwall` = 0 AND `readonly` = 0  AND ( `contact`.`rel` IN ( %d , %d ) OR `user`.`page-flags` = %d ) LIMIT 1",
  67                                         intval($owner),
  68                                         intval($cid),
  69                                         intval(Contact::SHARING),
  70                                         intval(Contact::FRIEND),
  71                                         intval(Contact::PAGE_COMMUNITY)
  72                                 );
  73
  74                                 if (DBA::isResult($r)) {
  75                                         $verified = 2;
  76                                         return true;
  77                                 } else {
  78                                         $verified = 1;
  79                                 }
  80                         }
  81                 }
  82
  83                 return false;
  84         }
  85
  86         /// @TODO $groups should be array
  87         public static function getPermissionsSQLByUserId($owner_id, $remote_verified = false, $groups = null)
  88         {
  89                 $local_user = local_user();
  90                 $remote_user = remote_user();
  91
  92                 /*
  93                  * Construct permissions
  94                  *
  95                  * default permissions - anonymous user
  96                  */
  97                 $sql = " AND allow_cid = ''
  98                                  AND allow_gid = ''
  99                                  AND deny_cid  = ''
 100                                  AND deny_gid  = ''
 101                 ";
 102
 103                 /*
 104                  * Profile owner - everything is visible
 105                  */
 106                 if ($local_user && $local_user == $owner_id) {
 107                         $sql = '';
 108                 /*
 109                  * Authenticated visitor. Unless pre-verified,
 110                  * check that the contact belongs to this $owner_id
 111                  * and load the groups the visitor belongs to.
 112                  * If pre-verified, the caller is expected to have already
 113                  * done this and passed the groups into this function.
 114                  */
 115                 } elseif ($remote_user) {
 116                         /*
 117                          * Authenticated visitor. Unless pre-verified,
 118                          * check that the contact belongs to this $owner_id
 119                          * and load the groups the visitor belongs to.
 120                          * If pre-verified, the caller is expected to have already
 121                          * done this and passed the groups into this function.
 122                          */
 123
 124                         if (!$remote_verified) {
 125                                 if (DBA::exists('contact', ['id' => $remote_user, 'uid' => $owner_id, 'blocked' => false])) {
 126                                         $remote_verified = true;
 127                                         $groups = Group::getIdsByContactId($remote_user);
 128                                 }
 129                         }
 130
 131                         if ($remote_verified) {
 132                                 $gs = '<<>>'; // should be impossible to match
 133
 134                                 if (is_array($groups)) {
 135                                         foreach ($groups as $g) {
 136                                                 $gs .= '|<' . intval($g) . '>';
 137                                         }
 138                                 }
 139
 140                                 $sql = sprintf(
 141                                         " AND ( NOT (deny_cid REGEXP '<%d>' OR deny_gid REGEXP '%s')
 142                                           AND ( allow_cid REGEXP '<%d>' OR allow_gid REGEXP '%s' OR ( allow_cid = '' AND allow_gid = '') )
 143                                           )
 144                                         ",
 145                                         intval($remote_user),
 146                                         DBA::escape($gs),
 147                                         intval($remote_user),
 148                                         DBA::escape($gs)
 149                                 );
 150                         }
 151                 }
 152                 return $sql;
 153         }
 154
 155 }