From 0324e078f8a9c9ac8141cbcd03929c66e51319ca Mon Sep 17 00:00:00 2001
From: Roeland Jago Douma <roeland@famdouma.nl>
Date: Mon, 19 Apr 2021 12:53:49 +0200
Subject: [PATCH] Require read permissions for federated shares

Else they end up as weird shares that can't be properly utilized by
other parties anyway.

Signed-off-by: Roeland Jago Douma <roeland@famdouma.nl>
---
 apps/federatedfilesharing/lib/FederatedShareProvider.php | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/apps/federatedfilesharing/lib/FederatedShareProvider.php b/apps/federatedfilesharing/lib/FederatedShareProvider.php
index dfcc717554..4660e1ccf3 100644
--- a/apps/federatedfilesharing/lib/FederatedShareProvider.php
+++ b/apps/federatedfilesharing/lib/FederatedShareProvider.php
@@ -37,6 +37,7 @@ namespace OCA\FederatedFileSharing;
 
 use OC\Share20\Exception\InvalidShare;
 use OC\Share20\Share;
+use OCP\Constants;
 use OCP\DB\QueryBuilder\IQueryBuilder;
 use OCP\Federation\ICloudFederationProviderManager;
 use OCP\Federation\ICloudIdManager;
@@ -206,6 +207,13 @@ class FederatedShareProvider implements IShareProvider {
 			throw new \Exception($message_t);
 		}
 
+		// Federated shares always have read permissions
+		if (($share->getPermissions() & Constants::PERMISSION_READ) === 0) {
+			$message = 'Federated shares require read permissions';
+			$message_t = $this->l->t('Federated shares require read permissions');
+			$this->logger->debug($message, ['app' => 'Federated File Sharing']);
+			throw new \Exception($message_t);
+		}
 
 		$share->setSharedWith($cloudId->getId());