Added core:TargetedID filter, for adding eduPersonTargetedID attribute.

git-svn-id: https://simplesamlphp.googlecode.com/svn/trunk@821 44740490-163a-0410-bde0-09ae8108e29a

modules/core/lib/Auth/Process/TargetedID.php

+<?php
+
+/**
+ * Filter to generate the eduPersonTargetedID attribute.
+ *
+ * By default, this filter will generate the ID based on the UserID of the current user.
+ * This is by default generated from the attribute configured in 'userid.attribute' in the
+ * metadata. If this attribute isn't present, the userid will be generated from the
+ * eduPersonPrincipalName attribute, if it is present.
+ *
+ * It is possible to generate this attribute from another attribute by specifying this attribute
+ * in this configuration.
+ *
+ * Example - generate from user ID:
+ * <code>
+ * 'authproc' => array(
+ *   array('core:TargetedID'),
+ *   ),
+ * </code>
+ *
+ * Example - generate from mail-attribute:
+ * <code>
+ * 'authproc' => array(
+ *   array('core:TargetedID' , 'attribute' => 'mail'),
+ *   ),
+ * </code>
+ *
+ * @author Olav Morken, UNINETT AS.
+ * @package simpleSAMLphp
+ * @version $Id$
+ */
+class sspmod_core_Auth_Process_TargetedID extends SimpleSAML_Auth_ProcessingFilter {
+
+
+	/**
+	 * The attribute we should generate the targeted id from, or NULL if we should use the
+	 * UserID.
+	 */
+	private $attribute = NULL;
+
+
+	/**
+	 * Initialize this filter.
+	 *
+	 * @param array $config  Configuration information about this filter.
+	 * @param mixed $reserved  For future use.
+	 */
+	public function __construct($config, $reserved) {
+		parent::__construct($config, $reserved);
+
+		assert('is_array($config)');
+
+		if (array_key_exists('attribute', $config)) {
+			$this->attribute = $config['attribute'];
+			if (!is_string($this->attribute)) {
+				throw new Exception('Invalid attribute name given to core:TargetedID filter.');
+			}
+		}
+	}
+
+
+	/**
+	 * Apply filter to add the targeted ID.
+	 *
+	 * @param array &$state  The current state.
+	 */
+	public function process(&$state) {
+		assert('is_array($state)');
+		assert('array_key_exists("Attributes", $state)');
+
+		if ($this->attribute === NULL) {
+			if (!array_key_exists('UserID', $state)) {
+				throw new Exception('core:TargetedID: Missing UserID for this user. Please' .
+					' check the \'userid.attribute\' option in the metadata against the' .
+					' attributes provided by the authentication source.');
+			}
+
+			$userID = $state['UserID'];
+		} else {
+			if (!array_key_exists($this->attribute, $state['Attributes'])) {
+				throw new Exception('core:TargetedID: Missing attribute \'' . $this->attribute .
+					'\', which is needed to generate the targeted ID.');
+			}
+
+			$userID = $state['Attributes'][$this->attribute];
+		}
+
+
+		$secretSalt = SimpleSAML_Configuration::getInstance()->getString('secretsalt');
+		if ($secretSalt === 'defaultsecretsalt') {
+			throw new Exception('The "secretsalt" configuration option must be set to a secret' .
+			                    ' value.');
+		}
+
+		if (array_key_exists('Source', $state)) {
+			$srcID = self::getEntityId($state['Source']);
+		} else {
+			$srcID = '';
+		}
+
+		if (array_key_exists('Destination', $state)) {
+			$dstID = self::getEntityId($state['Destination']);
+		} else {
+			$dstID = '';
+		}
+
+		$uidData = 'uidhashbase' . $secretSalt;
+		$uidData .= strlen($srcID) . ':' . $srcID;
+		$uidData .= strlen($dstID) . ':' . $dstID;
+		$uidData .= strlen($userID) . ':' . $userID;
+		$uidData .= $secretSalt;
+
+		$state['Attributes']['eduPersonTargetedID'] = array(hash('sha1', $uidData));
+	}
+
+
+	/**
+	 * Generate ID from entity metadata.
+	 *
+	 * This function takes in the metadata of an entity, and attempts to generate
+	 * an unique identifier based on that.
+	 *
+	 * @param array $metadata  The metadata of the entity.
+	 * @return string  The unique identifier for the entity.
+	 */
+	private static function getEntityId($metadata) {
+		assert('is_array($metadata)');
+
+		$id = '';
+
+		if (array_key_exists('metadata-set', $metadata)) {
+			$set = $metadata['metadata-set'];
+			$id .= 'set' . strlen($set) . ':' . $set;
+		}
+
+		if (array_key_exists('entityid', $metadata)) {
+			$entityid = $metadata['entityid'];
+			$id .= 'set' . strlen($entityid) . ':' . $entityid;
+		}
+
+		return $id;
+	}
+
+}
+
+?>
\ No newline at end of file