| 1 | <?php |
| 2 | /* |
| 3 | +--------------------------------------------------------------------+ |
| 4 | | CiviCRM version 4.6 | |
| 5 | +--------------------------------------------------------------------+ |
| 6 | | Copyright CiviCRM LLC (c) 2004-2014 | |
| 7 | +--------------------------------------------------------------------+ |
| 8 | | This file is a part of CiviCRM. | |
| 9 | | | |
| 10 | | CiviCRM is free software; you can copy, modify, and distribute it | |
| 11 | | under the terms of the GNU Affero General Public License | |
| 12 | | Version 3, 19 November 2007 and the CiviCRM Licensing Exception. | |
| 13 | | | |
| 14 | | CiviCRM is distributed in the hope that it will be useful, but | |
| 15 | | WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 16 | | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. | |
| 17 | | See the GNU Affero General Public License for more details. | |
| 18 | | | |
| 19 | | You should have received a copy of the GNU Affero General Public | |
| 20 | | License and the CiviCRM Licensing Exception along | |
| 21 | | with this program; if not, contact CiviCRM LLC | |
| 22 | | at info[AT]civicrm[DOT]org. If you have questions about the | |
| 23 | | GNU Affero General Public License or the licensing of CiviCRM, | |
| 24 | | see the CiviCRM license FAQ at http://civicrm.org/licensing | |
| 25 | +--------------------------------------------------------------------+ |
| 26 | */ |
| 27 | |
| 28 | namespace Civi\API\Subscriber; |
| 29 | |
| 30 | use Civi\API\Events; |
| 31 | use Symfony\Component\EventDispatcher\EventSubscriberInterface; |
| 32 | |
| 33 | /** |
| 34 | * Given an entity which dynamically attaches itself to another entity, |
| 35 | * determine if one has permission to the other entity. |
| 36 | * |
| 37 | * Example: Suppose one tries to manipulate a File which is attached to a |
| 38 | * Mailing. DynamicFKAuthorization will enforce permissions on the File by |
| 39 | * imitating the permissions of the Mailing. |
| 40 | * |
| 41 | * Note: This enforces a constraint: all matching API calls must define |
| 42 | * either "id" (e.g. for the file) or "entity_table". |
| 43 | * |
| 44 | * Note: The permission guard does not exactly authorize the request, but it |
| 45 | * may veto authorization. |
| 46 | */ |
| 47 | class DynamicFKAuthorization implements EventSubscriberInterface { |
| 48 | |
| 49 | /** |
| 50 | * @return array |
| 51 | */ |
| 52 | public static function getSubscribedEvents() { |
| 53 | return array( |
| 54 | Events::AUTHORIZE => array( |
| 55 | array('onApiAuthorize', Events::W_EARLY), |
| 56 | ), |
| 57 | ); |
| 58 | } |
| 59 | |
| 60 | /** |
| 61 | * @var \Civi\API\Kernel |
| 62 | */ |
| 63 | protected $kernel; |
| 64 | |
| 65 | /** |
| 66 | * @var string, the entity for which we want to manage permissions |
| 67 | */ |
| 68 | protected $entityName; |
| 69 | |
| 70 | /** |
| 71 | * @var array <string> the actions for which we want to manage permissions |
| 72 | */ |
| 73 | protected $actions; |
| 74 | |
| 75 | /** |
| 76 | * @var string, SQL; a query which looks up the related entity |
| 77 | * |
| 78 | * ex: "SELECT if(cf.id,1,0) as is_valid, cef.entity_table, cef.entity_id |
| 79 | * FROM civicrm_file cf |
| 80 | * INNER JOIN civicrm_entity_file cef ON cf.id = cef.file_id |
| 81 | * WHERE cf.id = %1" |
| 82 | * |
| 83 | * Note: %1 is a parameter |
| 84 | * Note: There are three parameters |
| 85 | * - is_valid: "1" if %1 identifies an actual record; otherwise "0" |
| 86 | * - entity_table: NULL or the name of a related table |
| 87 | * - entity_id: NULL or the ID of a row in the related table |
| 88 | */ |
| 89 | protected $lookupDelegateSql; |
| 90 | |
| 91 | /** |
| 92 | * @var array list of related tables for which FKs are allowed |
| 93 | */ |
| 94 | protected $allowedDelegates; |
| 95 | |
| 96 | /** |
| 97 | * @param \Civi\API\Kernel $kernel |
| 98 | * The API kernel. |
| 99 | * @param string $entityName |
| 100 | * The entity for which we want to manage permissions (e.g. "File" or |
| 101 | * "Note"). |
| 102 | * @param array $actions |
| 103 | * The actions for which we want to manage permissions (e.g. "create", |
| 104 | * "get", "delete"). |
| 105 | * @param string $lookupDelegateSql |
| 106 | * See docblock in DynamicFKAuthorization::$lookupDelegateSql. |
| 107 | * @param array|NULL $allowedDelegates |
| 108 | * e.g. "civicrm_mailing","civicrm_activity"; NULL to allow any. |
| 109 | */ |
| 110 | public function __construct($kernel, $entityName, $actions, $lookupDelegateSql, $allowedDelegates = NULL) { |
| 111 | $this->kernel = $kernel; |
| 112 | $this->entityName = $entityName; |
| 113 | $this->actions = $actions; |
| 114 | $this->lookupDelegateSql = $lookupDelegateSql; |
| 115 | $this->allowedDelegates = $allowedDelegates; |
| 116 | } |
| 117 | |
| 118 | /** |
| 119 | * @param \Civi\API\Event\AuthorizeEvent $event |
| 120 | * API authorization event. |
| 121 | * @throws \API_Exception |
| 122 | * @throws \Civi\API\Exception\UnauthorizedException |
| 123 | */ |
| 124 | public function onApiAuthorize(\Civi\API\Event\AuthorizeEvent $event) { |
| 125 | $apiRequest = $event->getApiRequest(); |
| 126 | if ($apiRequest['version'] == 3 && $apiRequest['entity'] == $this->entityName && in_array(strtolower($apiRequest['action']), $this->actions)) { |
| 127 | if (/*!$isTrusted */ |
| 128 | empty($apiRequest['params']['id']) && empty($apiRequest['params']['entity_table']) |
| 129 | ) { |
| 130 | throw new \API_Exception("Mandatory key(s) missing from params array: 'id' or 'entity_table'"); |
| 131 | } |
| 132 | |
| 133 | if (isset($apiRequest['params']['id'])) { |
| 134 | list($isValidId, $entityTable, $entityId) = $this->getDelegate($apiRequest['params']['id']); |
| 135 | if ($isValidId && $entityTable && $entityId) { |
| 136 | $this->authorizeDelegate($apiRequest['action'], $entityTable, $entityId, $apiRequest); |
| 137 | $this->preventReassignment($apiRequest['params']['id'], $entityTable, $entityId, $apiRequest); |
| 138 | return; |
| 139 | } |
| 140 | elseif ($isValidId) { |
| 141 | throw new \API_Exception("Failed to match record to related entity"); |
| 142 | } |
| 143 | elseif (!$isValidId && strtolower($apiRequest['action']) == 'get') { |
| 144 | // The matches will be an empty set; doesn't make a difference if we |
| 145 | // reject or accept. |
| 146 | // To pass SyntaxConformanceTest, we won't veto "get" on empty-set. |
| 147 | return; |
| 148 | } |
| 149 | } |
| 150 | |
| 151 | if (isset($apiRequest['params']['entity_table'])) { |
| 152 | $this->authorizeDelegate( |
| 153 | $apiRequest['action'], |
| 154 | $apiRequest['params']['entity_table'], |
| 155 | \CRM_Utils_Array::value('entity_id', $apiRequest['params'], NULL), |
| 156 | $apiRequest |
| 157 | ); |
| 158 | return; |
| 159 | } |
| 160 | |
| 161 | throw new \API_Exception("Failed to run permission check"); |
| 162 | } |
| 163 | } |
| 164 | |
| 165 | /** |
| 166 | * @param string $action |
| 167 | * The API action (e.g. "create"). |
| 168 | * @param string $entityTable |
| 169 | * The target entity table (e.g. "civicrm_mailing"). |
| 170 | * @param int|NULL $entityId |
| 171 | * The target entity ID. |
| 172 | * @param array $apiRequest |
| 173 | * The full API request. |
| 174 | * @throws \API_Exception |
| 175 | * @throws \Civi\API\Exception\UnauthorizedException |
| 176 | */ |
| 177 | public function authorizeDelegate($action, $entityTable, $entityId, $apiRequest) { |
| 178 | $entity = $this->getDelegatedEntityName($entityTable); |
| 179 | if (!$entity) { |
| 180 | throw new \API_Exception("Failed to run permission check: Unrecognized target entity ($entityTable)"); |
| 181 | } |
| 182 | |
| 183 | if ($this->isTrusted($apiRequest)) { |
| 184 | return; |
| 185 | } |
| 186 | |
| 187 | $params = array('check_permissions' => 1); |
| 188 | if ($entityId) { |
| 189 | $params['id'] = $entityId; |
| 190 | } |
| 191 | |
| 192 | if (!$this->kernel->runAuthorize($entity, $this->getDelegatedAction($action), $params)) { |
| 193 | throw new \Civi\API\Exception\UnauthorizedException("Authorization failed on ($entity,$entityId)"); |
| 194 | } |
| 195 | } |
| 196 | |
| 197 | /** |
| 198 | * If the request attempts to change the entity_table/entity_id of an |
| 199 | * existing record, then generate an error. |
| 200 | * |
| 201 | * @param int $fileId |
| 202 | * The main record being changed. |
| 203 | * @param string $entityTable |
| 204 | * The saved FK. |
| 205 | * @param int $entityId |
| 206 | * The saved FK. |
| 207 | * @param array $apiRequest |
| 208 | * The full API request. |
| 209 | * @throws \API_Exception |
| 210 | */ |
| 211 | public function preventReassignment($fileId, $entityTable, $entityId, $apiRequest) { |
| 212 | if (strtolower($apiRequest['action']) == 'create' && $fileId && !$this->isTrusted($apiRequest)) { |
| 213 | if (isset($apiRequest['params']['entity_table']) && $entityTable != $apiRequest['params']['entity_table']) { |
| 214 | throw new \API_Exception("Cannot modify entity_table"); |
| 215 | } |
| 216 | if (isset($apiRequest['params']['entity_id']) && $entityId != $apiRequest['params']['entity_id']) { |
| 217 | throw new \API_Exception("Cannot modify entity_id"); |
| 218 | } |
| 219 | } |
| 220 | } |
| 221 | |
| 222 | /** |
| 223 | * @param string $entityTable |
| 224 | * The target entity table (e.g. "civicrm_mailing" or "civicrm_activity"). |
| 225 | * @return string|NULL |
| 226 | * The target entity name (e.g. "Mailing" or "Activity"). |
| 227 | */ |
| 228 | public function getDelegatedEntityName($entityTable) { |
| 229 | if ($this->allowedDelegates === NULL || in_array($entityTable, $this->allowedDelegates)) { |
| 230 | $className = \CRM_Core_DAO_AllCoreTables::getClassForTable($entityTable); |
| 231 | if ($className) { |
| 232 | $entityName = \CRM_Core_DAO_AllCoreTables::getBriefName($className); |
| 233 | if ($entityName) { |
| 234 | return $entityName; |
| 235 | } |
| 236 | } |
| 237 | } |
| 238 | return NULL; |
| 239 | } |
| 240 | |
| 241 | /** |
| 242 | * @param string $action |
| 243 | * API action name -- e.g. "create" ("When running *create* on a file..."). |
| 244 | * @return string |
| 245 | * e.g. "create" ("Check for *create* permission on the mailing to which |
| 246 | * it is attached.") |
| 247 | */ |
| 248 | public function getDelegatedAction($action) { |
| 249 | switch ($action) { |
| 250 | case 'get': |
| 251 | // reading attachments requires reading the other entity |
| 252 | return 'get'; |
| 253 | |
| 254 | case 'create': |
| 255 | case 'delete': |
| 256 | // creating/updating/deleting an attachment requires editing |
| 257 | // the other entity |
| 258 | return 'create'; |
| 259 | |
| 260 | default: |
| 261 | return $action; |
| 262 | } |
| 263 | } |
| 264 | |
| 265 | /** |
| 266 | * @param int $id |
| 267 | * e.g. file ID. |
| 268 | * @return array |
| 269 | * (0 => bool $isValid, 1 => string $entityTable, 2 => int $entityId) |
| 270 | */ |
| 271 | public function getDelegate($id) { |
| 272 | $query = \CRM_Core_DAO::executeQuery($this->lookupDelegateSql, array( |
| 273 | 1 => array($id, 'Positive'), |
| 274 | )); |
| 275 | if ($query->fetch()) { |
| 276 | return array($query->is_valid, $query->entity_table, $query->entity_id); |
| 277 | } |
| 278 | else { |
| 279 | return array(FALSE, NULL, NULL); |
| 280 | } |
| 281 | } |
| 282 | |
| 283 | /** |
| 284 | * @param array $apiRequest |
| 285 | * The full API request. |
| 286 | * @return bool |
| 287 | */ |
| 288 | public function isTrusted($apiRequest) { |
| 289 | // isn't this redundant? |
| 290 | return empty($apiRequest['params']['check_permissions']) or $apiRequest['params']['check_permissions'] == FALSE; |
| 291 | } |
| 292 | |
| 293 | } |