From 68c44bb6427632e237792bd75d874be4b4562f3f Mon Sep 17 00:00:00 2001
From: Maxence Lange <maxence@artificial-owl.com>
Date: Mon, 29 Oct 2018 10:03:52 +0100
Subject: [PATCH] shares are displayed to users with resharing rights

Signed-off-by: Maxence Lange <maxence@artificial-owl.com>
---
 .../lib/Controller/ShareAPIController.php     | 38 +++++++++++++++++++
 lib/private/Share20/DefaultShareProvider.php  | 22 +++++------
 2 files changed, 49 insertions(+), 11 deletions(-)

diff --git a/apps/files_sharing/lib/Controller/ShareAPIController.php b/apps/files_sharing/lib/Controller/ShareAPIController.php
index 61fad5d2b1..fc03a357f3 100644
--- a/apps/files_sharing/lib/Controller/ShareAPIController.php
+++ b/apps/files_sharing/lib/Controller/ShareAPIController.php
@@ -720,14 +720,23 @@ class ShareAPIController extends OCSController {
 		}
 
 		$formatted = [];
+		$resharingRight = false;
 		foreach ($shares as $share) {
 			try {
 				$formatted[] = $this->formatShare($share, $path);
+				if (!$resharingRight && $this->shareProviderResharingRights($this->currentUser, $share)) {
+					$resharingRight = true;
+				}
+
 			} catch (NotFoundException $e) {
 				//Ignore share
 			}
 		}
 
+		if (!$resharingRight) {
+			$formatted = [];
+		}
+
 		if ($include_tags) {
 			$formatted = Helper::populateTags($formatted, 'file_source', \OC::$server->getTagManager());
 		}
@@ -1102,4 +1111,33 @@ class ShareAPIController extends OCSController {
 
 		return $this->serverContainer->query('\OCA\Spreed\Share\Helper\ShareAPIController');
 	}
+
+
+	/**
+	 * Returns if we can find resharing rights in an IShare object for a specific user.
+	 *
+	 * @param string $userId
+	 * @param IShare $share
+	 * @return bool
+	 */
+	private function shareProviderResharingRights(string $userId, IShare $share): bool {
+		if ($share->getShareOwner() === $userId) {
+			return true;
+		}
+
+		if ((\OCP\Constants::PERMISSION_SHARE & $share->getPermissions()) === 0) {
+			return false;
+		}
+
+		if ($share->getShareType() === \OCP\Share::SHARE_TYPE_USER && $share->getSharedWith() === $userId) {
+			return true;
+		}
+
+		if ($share->getShareType() === \OCP\Share::SHARE_TYPE_GROUP && $this->groupManager->isInGroup($userId, $share->getSharedWith())) {
+			return true;
+		}
+
+		return false;
+	}
+
 }
diff --git a/lib/private/Share20/DefaultShareProvider.php b/lib/private/Share20/DefaultShareProvider.php
index 5011105454..53fd1728b8 100644
--- a/lib/private/Share20/DefaultShareProvider.php
+++ b/lib/private/Share20/DefaultShareProvider.php
@@ -617,18 +617,18 @@ class DefaultShareProvider implements IShareProvider {
 		/**
 		 * Reshares for this user are shares where they are the owner.
 		 */
-		if ($reshares === false) {
-			$qb->andWhere($qb->expr()->eq('uid_initiator', $qb->createNamedParameter($userId)));
+		if ($node === null) {
+			if ($reshares === false) {
+				$qb->andWhere($qb->expr()->eq('uid_initiator', $qb->createNamedParameter($userId)));
+			} else {
+				$qb->andWhere(
+					$qb->expr()->orX(
+						$qb->expr()->eq('uid_owner', $qb->createNamedParameter($userId)),
+						$qb->expr()->eq('uid_initiator', $qb->createNamedParameter($userId))
+					)
+				);
+			}
 		} else {
-			$qb->andWhere(
-				$qb->expr()->orX(
-					$qb->expr()->eq('uid_owner', $qb->createNamedParameter($userId)),
-					$qb->expr()->eq('uid_initiator', $qb->createNamedParameter($userId))
-				)
-			);
-		}
-
-		if ($node !== null) {
 			$qb->andWhere($qb->expr()->eq('file_source', $qb->createNamedParameter($node->getId())));
 		}