[stable32] hide share token if share has more permissions than the current user

apps/files_sharing/lib/Controller/ShareAPIController.php

@@ -77,6 +77,7 @@
 class ShareAPIController extends OCSController {
 
 	private ?Node $lockedNode = null;
+	/** @var array<bool> $trustedServerCache */
 	private array $trustedServerCache = [];
 
 	/**
@@ -237,6 +238,10 @@ protected function formatShare(IShare $share, ?Node $recipientNode = null): arra
 			$result['expiration'] = $expiration->format('Y-m-d 00:00:00');
 		}
 
+		$currentUserPermissions = $recipientNode?->getPermissions() ?? Constants::PERMISSION_ALL;
+		$userHasEnoughPermissions = ($currentUserPermissions & $share->getPermissions()) === $share->getPermissions();
+		$token = $userHasEnoughPermissions ? $share->getToken() : null;
+
 		if ($share->getShareType() === IShare::TYPE_USER) {
 			$sharedWith = $this->userManager->get($share->getSharedWith());
 			$result['share_with'] = $share->getSharedWith();
@@ -262,6 +267,7 @@ protected function formatShare(IShare $share, ?Node $recipientNode = null): arra
 			$result['share_with'] = $share->getSharedWith();
 			$result['share_with_displayname'] = $group !== null ? $group->getDisplayName() : $share->getSharedWith();
 		} elseif ($share->getShareType() === IShare::TYPE_LINK) {
+			$url = $token ? $this->urlGenerator->linkToRouteAbsolute('files_sharing.sharecontroller.showShare', ['token' => $token]) : null;
 
 			// "share_with" and "share_with_displayname" for passwords of link
 			// shares was deprecated in Nextcloud 15, use "password" instead.
@@ -272,23 +278,23 @@ protected function formatShare(IShare $share, ?Node $recipientNode = null): arra
 
 			$result['send_password_by_talk'] = $share->getSendPasswordByTalk();
 
-			$result['token'] = $share->getToken();
-			$result['url'] = $this->urlGenerator->linkToRouteAbsolute('files_sharing.sharecontroller.showShare', ['token' => $share->getToken()]);
+			$result['token'] = $token;
+			$result['url'] = $url;
 		} elseif ($share->getShareType() === IShare::TYPE_REMOTE) {
 			$result['share_with'] = $share->getSharedWith();
 			$result['share_with_displayname'] = $this->getCachedFederatedDisplayName($share->getSharedWith());
-			$result['token'] = $share->getToken();
+			$result['token'] = $token;
 		} elseif ($share->getShareType() === IShare::TYPE_REMOTE_GROUP) {
 			$result['share_with'] = $share->getSharedWith();
 			$result['share_with_displayname'] = $this->getDisplayNameFromAddressBook($share->getSharedWith(), 'CLOUD');
-			$result['token'] = $share->getToken();
+			$result['token'] = $token;
 		} elseif ($share->getShareType() === IShare::TYPE_EMAIL) {
 			$result['share_with'] = $share->getSharedWith();
 			$result['password'] = $share->getPassword();
 			$result['password_expiration_time'] = $share->getPasswordExpirationTime() !== null ? $share->getPasswordExpirationTime()->format(\DateTime::ATOM) : null;
 			$result['send_password_by_talk'] = $share->getSendPasswordByTalk();
 			$result['share_with_displayname'] = $this->getDisplayNameFromAddressBook($share->getSharedWith(), 'EMAIL');
-			$result['token'] = $share->getToken();
+			$result['token'] = $token;
 		} elseif ($share->getShareType() === IShare::TYPE_CIRCLE) {
 			// getSharedWith() returns either "name (type, owner)" or
 			// "name (type, owner) [id]", depending on the Teams app version.

apps/files_sharing/lib/ResponseDefinitions.php

@@ -54,7 +54,7 @@
  *     token: ?string,
  *     uid_file_owner: string,
  *     uid_owner: string,
- *     url?: string,
+ *     url?: string|null,
  * }
  *
  * @psalm-type Files_SharingDeletedShare = array{

apps/files_sharing/openapi.json

@@ -700,7 +700,8 @@
                         "type": "string"
                     },
                     "url": {
-                        "type": "string"
+                        "type": "string",
+                        "nullable": true
                     }
                 }
             },

build/integration/sharing_features/sharing-v1-part2.feature

@@ -23,6 +23,36 @@ Feature: sharing
     And User "user2" should be included in the response
     And User "user3" should not be included in the response
 
+Scenario: getting all shares of a file with reshares with link share with less permissions
+  Given user "user0" exists
+  And user "user1" exists
+  When as "user0" creating a share with
+    | path | textfile0.txt |
+    | shareType | 0 |
+    | shareWith | user1 |
+    | permissions | 17 |
+  Then the OCS status code should be "100"
+  And the HTTP status code should be "200"
+  When as "user0" creating a share with
+    | path | textfile0.txt |
+    | shareType | 3 |
+    | permissions | 19 |
+  Then the OCS status code should be "100"
+  And the HTTP status code should be "200"
+  And last link share can be downloaded
+  When As an "user1"
+  And sending "GET" to "/apps/files_sharing/api/v1/shares?reshares=true&path=textfile0 (2).txt"
+  Then the OCS status code should be "100"
+  And the HTTP status code should be "200"
+  And User "user1" should not be included in the response
+  Then the list of returned shares has 1 shares
+  And share 0 is returned with
+    | share_type             | 3 |
+    | uid_owner              | user0 |
+    | token                  | |
+    | url                    | |
+    | permissions            | 19 |
+
   Scenario: getting all shares of a file with a received share after revoking the resharing rights
     Given user "user0" exists
     And user "user1" exists

openapi.json

@@ -2798,7 +2798,8 @@
                         "type": "string"
                     },
                     "url": {
-                        "type": "string"
+                        "type": "string",
+                        "nullable": true
                     }
                 }
             },