[locationinfo] Fix crash with null-deref in exchange backend

1 files changed, 15 insertions, 13 deletions

diff --git a/modules-available/locationinfo/inc/coursebackend/coursebackend_exchange.inc.php b/modules-available/locationinfo/inc/coursebackend/coursebackend_exchange.inc.php
index a0eca0ec..5920231f 100755
--- a/modules-available/locationinfo/inc/coursebackend/coursebackend_exchange.inc.php
+++ b/modules-available/locationinfo/inc/coursebackend/coursebackend_exchange.inc.php
@@ -12,6 +12,7 @@ spl_autoload_register(function ($class) {
 	require_once $file;
 });
 
+use jamesiarmes\PhpEws\ArrayType\NonEmptyArrayOfBaseFolderIdsType;
 use jamesiarmes\PhpEws\Client;
 use jamesiarmes\PhpEws\Enumeration\DefaultShapeNamesType;
 use jamesiarmes\PhpEws\Enumeration\DistinguishedFolderIdNameType;
@@ -186,13 +187,9 @@ class CourseBackend_Exchange extends CourseBackend
 	}
 
 	/**
-	 * @param \jamesiarmes\PhpEws\Client $client
-	 * @param \DateTime $startDate
-	 * @param \DateTime $endDate
-	 * @param string $roomAddress
 	 * @return \jamesiarmes\PhpEws\Type\CalendarItemType[]
 	 */
-	public function findEventsForRoom($client, $startDate, $endDate, $roomAddress)
+	public function findEventsForRoom(Client $client, DateTime $startDate, DateTime $endDate, string $roomAddress): array
 	{
 		$request = new FindItemType();
 		$request->Traversal = ItemQueryTraversalType::SHALLOW;
@@ -206,12 +203,20 @@ class CourseBackend_Exchange extends CourseBackend
 		$folderId->Id = DistinguishedFolderIdNameType::CALENDAR;
 		$folderId->Mailbox = new EmailAddressType();
 		$folderId->Mailbox->EmailAddress = $roomAddress;
+		$request->ParentFolderIds = new NonEmptyArrayOfBaseFolderIdsType();
 		$request->ParentFolderIds->DistinguishedFolderId[] = $folderId;
-		$response = $client->FindItem($request);
-		$response_messages = $response->ResponseMessages->FindItemResponseMessage;
-
+		try {
+			$response = $client->FindItem($request);
+		} catch (Exception $e) {
+			$this->addError('Exception calling FindItem: ' . $e->getMessage(), true);
+			return [];
+		}
+		if (!is_object($response->ResponseMessages)) {
+			$this->addError('FindItem returned response without ResponseMessages', true);
+			return [];
+		}
 		$items = [];
-		foreach ($response_messages as $response_message) {
+		foreach ($response->ResponseMessages->FindItemResponseMessage as $response_message) {
 			// Make sure the request succeeded.
 			if ($response_message->ResponseClass !== ResponseClassType::SUCCESS) {
 				$code = $response_message->ResponseCode;
@@ -224,10 +229,7 @@ class CourseBackend_Exchange extends CourseBackend
 		return $items;
 	}
 
-	/**
-	 * @return \jamesiarmes\PhpEws\Client
-	 */
-	public function getClient()
+	public function getClient(): Client
 	{
 		$client = new Client($this->serverAddress, $this->username, $this->password, $this->clientVersion);
 		$client->setTimezone($this->timezone);