nextcloud · DerDreschner · Jul 23, 2026
@@ -38,9 +38,11 @@
 
 use OCA\DAV\CalDAV\CalendarObject;
 use OCA\DAV\CalDAV\EventComparisonService;
+use OCP\Accounts\IAccountManager;
 use OCP\AppFramework\Utility\ITimeFactory;
 use OCP\Defaults;
 use OCP\IConfig;
+use OCP\IUser;
 use OCP\IUserSession;
 use OCP\Mail\IMailer;
 use OCP\Util;
@@ -83,6 +85,7 @@ class IMipPlugin extends SabreIMipPlugin {
 	public const METHOD_CANCEL = 'cancel';
 	public const IMIP_INDENT = 15; // Enough for the length of all body bullet items, in all languages
 	private EventComparisonService $eventComparisonService;
+	private IAccountManager $accountManager;
 
 	public function __construct(IConfig $config,
 		IMailer $mailer,
@@ -91,7 +94,8 @@ public function __construct(IConfig $config,
 		Defaults $defaults,
 		IUserSession $userSession,
 		IMipService $imipService,
-		EventComparisonService $eventComparisonService) {
+		EventComparisonService $eventComparisonService,
+		IAccountManager $accountManager) {
 		parent::__construct('');
 		$this->userSession = $userSession;
 		$this->config = $config;
@@ -101,6 +105,7 @@ public function __construct(IConfig $config,
 		$this->defaults = $defaults;
 		$this->imipService = $imipService;
 		$this->eventComparisonService = $eventComparisonService;
+		$this->accountManager = $accountManager;
 	}
 
 	public function initialize(DAV\Server $server): void {
@@ -202,21 +207,17 @@ public function schedule(Message $iTipMessage) {
 		}
 		$this->imipService->setL10n($attendee);
 
-		// Build the sender name.
+		$sender = substr($iTipMessage->sender, 7);
+
 		// Due to a bug in sabre, the senderName property for an iTIP message can actually also be a VObject Property
-		// If the iTIP message senderName is null or empty use the user session name as the senderName
 		if (($iTipMessage->senderName instanceof Parameter) && !empty(trim($iTipMessage->senderName->getValue()))) {
 			$senderName = trim($iTipMessage->senderName->getValue());
 		} elseif (is_string($iTipMessage->senderName) && !empty(trim($iTipMessage->senderName))) {
 			$senderName = trim($iTipMessage->senderName);
-		} elseif ($this->userSession->getUser() !== null) {
-			$senderName = trim($this->userSession->getUser()->getDisplayName());
 		} else {
-			$senderName = '';
+			$senderName = $this->getSenderNameFor($sender);
 		}
 
-		$sender = substr($iTipMessage->sender, 7);
-
 		$replyingAttendee = null;
 		switch (strtolower($iTipMessage->method)) {
 			case self::METHOD_REPLY:
@@ -319,6 +320,40 @@ public function schedule(Message $iTipMessage) {
 		}
 	}
 
+	/**
+	 * Messages are regularly brokered on behalf of somebody else, so the
+	 * session user's name is only used when the sender address is one of
+	 * theirs.
+	 */
+	private function getSenderNameFor(string $sender): ?string {
+		$user = $this->userSession->getUser();
+		if ($user !== null && $this->isAddressOfUser($sender, $user)) {
+			return trim($user->getDisplayName()) ?: null;
+		}
+
+		return null;
+	}
+
+	/**
+	 * Profile email addresses are part of the user's calendar-user-address-set
+	 * and therefore valid sender addresses next to the system email address.
+	 */
+	private function isAddressOfUser(string $address, IUser $user): bool {
+		if (strcasecmp((string)$user->getEMailAddress(), $address) === 0) {
+			return true;
+		}
+
+		$emailCollection = $this->accountManager->getAccount($user)
+			->getPropertyCollection(IAccountManager::COLLECTION_EMAIL);
+		foreach ($emailCollection->getProperties() as $property) {
+			if (strcasecmp($property->getValue(), $address) === 0) {
+				return true;
+			}
+		}
+
+		return false;
+	}
+
 	/**
 	 * @return ?VCalendar
 	 */

diff --git a/apps/dav/lib/Server.php b/apps/dav/lib/Server.php
@@ -324,7 +324,8 @@ public function __construct(IRequest $request, string $baseUri) {
 						\OC::$server->get(\OCP\Defaults::class),
 						$userSession,
 						\OC::$server->get(\OCA\DAV\CalDAV\Schedule\IMipService::class),
-						\OC::$server->get(\OCA\DAV\CalDAV\EventComparisonService::class)
+						\OC::$server->get(\OCA\DAV\CalDAV\EventComparisonService::class),
+						\OC::$server->get(\OCP\Accounts\IAccountManager::class),
 					));
 				}
 				$this->server->addPlugin(new \OCA\DAV\CalDAV\Search\SearchPlugin());

@@ -32,6 +32,10 @@
 use OCA\DAV\CalDAV\EventComparisonService;
 use OCA\DAV\CalDAV\Schedule\IMipPlugin;
 use OCA\DAV\CalDAV\Schedule\IMipService;
+use OCP\Accounts\IAccount;
+use OCP\Accounts\IAccountManager;
+use OCP\Accounts\IAccountProperty;
+use OCP\Accounts\IAccountPropertyCollection;
 use OCP\AppFramework\Utility\ITimeFactory;
 use OCP\Defaults;
 use OCP\IConfig;
@@ -90,6 +94,9 @@ class IMipPluginTest extends TestCase {
 	/** @var EventComparisonService|MockObject */
 	private $eventComparisonService;
 
+	/** @var IAccountManager|MockObject */
+	private $accountManager;
+
 	protected function setUp(): void {
 		$this->mailMessage = $this->createMock(IMessage::class);
 		$this->mailMessage->method('setFrom')->willReturn($this->mailMessage);
@@ -126,6 +133,8 @@ protected function setUp(): void {
 
 		$this->eventComparisonService = $this->createMock(EventComparisonService::class);
 
+		$this->accountManager = $this->createMock(IAccountManager::class);
+
 		$this->plugin = new IMipPlugin(
 			$this->config,
 			$this->mailer,
@@ -134,7 +143,8 @@ protected function setUp(): void {
 			$this->defaults,
 			$this->userSession,
 			$this->service,
-			$this->eventComparisonService
+			$this->eventComparisonService,
+			$this->accountManager,
 		);
 	}
 
@@ -226,6 +236,9 @@ public function testParsingSingle(): void {
 		$this->user->expects(self::any())
 			->method('getDisplayName')
 			->willReturn('Mr. Wizard');
+		$this->user->expects(self::any())
+			->method('getEMailAddress')
+			->willReturn('gandalf@wiz.ard');
 		$this->userSession->expects(self::any())
 			->method('getUser')
 			->willReturn($this->user);
@@ -430,6 +443,9 @@ public function testParsingRecurrence(): void {
 		$this->user->expects(self::any())
 			->method('getDisplayName')
 			->willReturn('Mr. Wizard');
+		$this->user->expects(self::any())
+			->method('getEMailAddress')
+			->willReturn('gandalf@wiz.ard');
 		$this->userSession->expects(self::any())
 			->method('getUser')
 			->willReturn($this->user);
@@ -561,6 +577,9 @@ public function testFailedDelivery(): void {
 		$this->user->expects(self::any())
 			->method('getDisplayName')
 			->willReturn('Mr. Wizard');
+		$this->user->expects(self::any())
+			->method('getEMailAddress')
+			->willReturn('gandalf@wiz.ard');
 		$this->userSession->expects(self::any())
 			->method('getUser')
 			->willReturn($this->user);
@@ -657,6 +676,9 @@ public function testNoOldEvent(): void {
 		$this->user->expects(self::any())
 			->method('getDisplayName')
 			->willReturn('Mr. Wizard');
+		$this->user->expects(self::any())
+			->method('getEMailAddress')
+			->willReturn('gandalf@wiz.ard');
 		$this->userSession->expects(self::any())
 			->method('getUser')
 			->willReturn($this->user);
@@ -750,6 +772,9 @@ public function testNoButtons(): void {
 		$this->user->expects(self::any())
 			->method('getDisplayName')
 			->willReturn('Mr. Wizard');
+		$this->user->expects(self::any())
+			->method('getEMailAddress')
+			->willReturn('gandalf@wiz.ard');
 		$this->userSession->expects(self::any())
 			->method('getUser')
 			->willReturn($this->user);
@@ -783,4 +808,161 @@ public function testNoButtons(): void {
 		$this->plugin->schedule($message);
 		$this->assertEquals('1.1', $message->getScheduleStatus());
 	}
+
+	/**
+	 * Runs schedule() for an organizer sourced REQUEST whose iTip message
+	 * carries no sender name and captures the resulting From and Reply-To
+	 * headers.
+	 *
+	 * @return array{from: ?array, replyTo: ?array}
+	 */
+	private function scheduleWithoutSenderName(string $organizer, string $recipient): array {
+		$vCalendar = new VCalendar();
+		$vEvent = new VEvent($vCalendar, 'VEVENT', [
+			'UID' => 'uid-1234',
+			'SEQUENCE' => 1,
+			'SUMMARY' => 'Meeting',
+			'DTSTART' => new \DateTime('2017-01-01 00:00:00'),
+		]);
+		$vEvent->add('ORGANIZER', 'mailto:' . $organizer);
+		$vEvent->add('ATTENDEE', 'mailto:' . $recipient, ['RSVP' => 'TRUE', 'CN' => 'Frodo']);
+
+		$message = new Message();
+		$message->method = 'REQUEST';
+		$message->message = $vCalendar;
+		$message->sender = 'mailto:' . $organizer;
+		$message->senderName = null;
+		$message->recipient = 'mailto:' . $recipient;
+
+		$capturedFrom = null;
+		$capturedReplyTo = null;
+		$mailMessage = $this->createMock(IMessage::class);
+		$mailMessage->method('setTo')->willReturn($mailMessage);
+		$mailMessage->method('setFrom')
+			->willReturnCallback(function (array $from) use (&$capturedFrom, $mailMessage) {
+				$capturedFrom = $from;
+				return $mailMessage;
+			});
+		$mailMessage->method('setReplyTo')
+			->willReturnCallback(function (array $replyTo) use (&$capturedReplyTo, $mailMessage) {
+				$capturedReplyTo = $replyTo;
+				return $mailMessage;
+			});
+
+		$mailer = $this->createMock(IMailer::class);
+		$mailer->method('createMessage')->willReturn($mailMessage);
+		$mailer->method('createEMailTemplate')->willReturn($this->emailTemplate);
+		$mailer->method('validateMailAddress')->with($recipient)->willReturn(true);
+		$mailer->method('send')->willReturn([]);
+
+		$this->service->method('getLastOccurrence')->willReturn(1496912700);
+		$this->service->method('getCurrentAttendee')->willReturn($vEvent->select('ATTENDEE')[0]);
+		$this->service->method('isRoomOrResource')->willReturn(false);
+		$this->service->method('getAttendeeRsvpOrReqForParticipant')->willReturn(false);
+		$this->service->method('buildBodyData')->willReturn([
+			'meeting_title' => 'Meeting',
+			'invitee_name' => '',
+			'attendee_name' => $recipient,
+		]);
+		// Mirrors the real IMipService::getFrom() so assertions read like the
+		// actual mail header.
+		$this->service->method('getFrom')
+			->willReturnCallback(static function (?string $senderName, string $default): string {
+				return ($senderName === null || $senderName === '') ? $default : $senderName . ' via ' . $default;
+			});
+
+		$this->eventComparisonService->method('findModified')
+			->willReturn(['old' => [], 'new' => [$vEvent]]);
+
+		$plugin = new IMipPlugin(
+			$this->config,
+			$mailer,
+			$this->logger,
+			$this->timeFactory,
+			$this->defaults,
+			$this->userSession,
+			$this->service,
+			$this->eventComparisonService,
+			$this->accountManager,
+		);
+		$plugin->schedule($message);
+		self::assertSame('1.1', $message->getScheduleStatus());
+
+		return ['from' => $capturedFrom, 'replyTo' => $capturedReplyTo];
+	}
+
+	/**
+	 * Messages are regularly brokered on behalf of somebody else, so headers
+	 * must not fall back to the session user's name when the sender address
+	 * is not theirs.
+	 */
+	public function testSenderNameIsNotTakenFromAnUnrelatedSessionUser(): void {
+		$this->user->method('getUID')->willReturn('bilbo');
+		$this->user->method('getDisplayName')->willReturn('Bilbo Baggins');
+		$this->user->method('getEMailAddress')->willReturn('bilbo@hobb.it');
+
+		$result = $this->scheduleWithoutSenderName('a@example.com', 'frodo@hobb.it');
+
+		self::assertSame(['Instance Name 123'], array_values($result['from']));
+		self::assertSame(['a@example.com'], $result['replyTo']);
+	}
+
+	public function testSenderNameFallsBackToSessionUserWhenTheyAreTheSender(): void {
+		$this->user->method('getUID')->willReturn('gandalf');
+		$this->user->method('getDisplayName')->willReturn('Mr. Wizard');
+		$this->user->method('getEMailAddress')->willReturn('gandalf@wiz.ard');
+
+		$result = $this->scheduleWithoutSenderName('gandalf@wiz.ard', 'frodo@hobb.it');
+
+		self::assertSame(['Mr. Wizard via Instance Name 123'], array_values($result['from']));
+		self::assertSame(['gandalf@wiz.ard' => 'Mr. Wizard'], $result['replyTo']);
+	}
+
+	/**
+	 * The session user must also be recognized as the sender when sending
+	 * under one of their profile email aliases.
+	 */
+	public function testSenderNameUsesSessionUserForTheirAliasAddress(): void {
+		$this->user->method('getUID')->willReturn('carl');
+		$this->user->method('getDisplayName')->willReturn('Carl Session');
+		$this->user->method('getEMailAddress')->willReturn('carl@example.com');
+
+		$aliasProperty = $this->createMock(IAccountProperty::class);
+		$aliasProperty->method('getValue')->willReturn('Shared@Corp.example');
+		$emailCollection = $this->createMock(IAccountPropertyCollection::class);
+		$emailCollection->method('getProperties')->willReturn([$aliasProperty]);
+		$account = $this->createMock(IAccount::class);
+		$account->method('getPropertyCollection')
+			->with(IAccountManager::COLLECTION_EMAIL)
+			->willReturn($emailCollection);
+		$this->accountManager->method('getAccount')->with($this->user)->willReturn($account);
+
+		$result = $this->scheduleWithoutSenderName('shared@corp.example', 'frodo@hobb.it');
+
+		self::assertSame(['Carl Session via Instance Name 123'], array_values($result['from']));
+		self::assertSame(['shared@corp.example' => 'Carl Session'], $result['replyTo']);
+	}
+
+	public function testSenderNameStaysNeutralForBlankDisplayNames(): void {
+		$this->user->method('getUID')->willReturn('gandalf');
+		$this->user->method('getDisplayName')->willReturn('  ');
+		$this->user->method('getEMailAddress')->willReturn('gandalf@wiz.ard');
+
+		$result = $this->scheduleWithoutSenderName('gandalf@wiz.ard', 'frodo@hobb.it');
+
+		self::assertSame(['Instance Name 123'], array_values($result['from']));
+		self::assertSame(['gandalf@wiz.ard'], $result['replyTo']);
+	}
+
+	/**
+	 * Sessionless contexts: invitation link responses and background jobs.
+	 */
+	public function testSenderNameStaysNeutralWithoutSessionUser(): void {
+		$this->userSession = $this->createMock(IUserSession::class);
+
+		$result = $this->scheduleWithoutSenderName('a@example.com', 'frodo@hobb.it');
+
+		self::assertSame(['Instance Name 123'], array_values($result['from']));
+		self::assertSame(['a@example.com'], $result['replyTo']);
+	}
 }