From 5833b7b2a7a1b9f0a1eb4c2f3d74a7c7e2e51ed8 Mon Sep 17 00:00:00 2001
From: Wim Taymans <wtaymans@redhat.com>
Date: Fri, 28 Jun 2019 12:18:10 +0200
Subject: [PATCH] client: remove recursive permissions checks

Don't let permissions of an object influence the child permissions,
this is not so easy to manage and needs some more thought.
The result is now that it's possible to see a reference to a (parent)
id that is not visible, but that's ok.
---
 src/pipewire/client.c |  3 +--
 src/pipewire/global.c | 47 +++++++++++++------------------------------
 2 files changed, 15 insertions(+), 35 deletions(-)

diff --git a/src/pipewire/client.c b/src/pipewire/client.c
index aad218460..2011eee38 100644
--- a/src/pipewire/client.c
+++ b/src/pipewire/client.c
@@ -102,8 +102,7 @@ static uint32_t
 client_permission_func(struct pw_global *global,
 		       struct pw_client *client, void *data)
 {
-	struct pw_permission *p;
-	p = find_permission(client, global->id);
+	struct pw_permission *p = find_permission(client, global->id);
 	return p->permissions;
 }
 
diff --git a/src/pipewire/global.c b/src/pipewire/global.c
index 44bfbf6d1..fc9c8a519 100644
--- a/src/pipewire/global.c
+++ b/src/pipewire/global.c
@@ -41,29 +41,13 @@ struct impl {
 };
 
 /** \endcond */
-
-static inline uint32_t get_permissions(struct pw_global *global, struct pw_client *client, bool recurse)
-{
-	uint32_t perms;
-
-	if (client->permission_func == NULL)
-		return PW_PERM_RWX;
-
-	perms = client->permission_func(global, client, client->permission_data);
-
-	if (recurse) {
-		while (global->parent != NULL && global != global->parent) {
-			global = global->parent;
-			perms &= client->permission_func(global, client, client->permission_data);
-		}
-	}
-	return perms;
-}
-
 SPA_EXPORT
 uint32_t pw_global_get_permissions(struct pw_global *global, struct pw_client *client)
 {
-	return get_permissions(global, client, true);
+	if (client->permission_func == NULL)
+		return PW_PERM_RWX;
+
+	return client->permission_func(global, client, client->permission_data);
 }
 
 /** Create a new global
@@ -329,29 +313,25 @@ int pw_global_update_permissions(struct pw_global *global, struct pw_client *cli
 {
 	struct pw_core *core = global->core;
 	struct pw_resource *resource, *t;
-	struct pw_global *g;
-	uint32_t perms;
+	bool do_hide, do_show;
+
+	do_hide = PW_PERM_IS_R(old_permissions) && !PW_PERM_IS_R(new_permissions);
+	do_show = !PW_PERM_IS_R(old_permissions) && PW_PERM_IS_R(new_permissions);
+
+	pw_log_debug("client %p: permissions changed %d %08x -> %08x", client,
+			global->id, old_permissions, new_permissions);
 
 	pw_global_emit_permissions_changed(global, client, old_permissions, new_permissions);
 
-	spa_list_for_each(g, &global->child_list, child_link) {
-		if (g == global)
-			continue;
-		perms = get_permissions(g, client, false);
-		pw_global_update_permissions(g, client,
-				perms & old_permissions,
-				perms & new_permissions);
-	}
-
 	spa_list_for_each(resource, &core->registry_resource_list, link) {
 		if (resource->client != client)
 			continue;
 
-		if (PW_PERM_IS_R(old_permissions) && !PW_PERM_IS_R(new_permissions)) {
+		if (do_hide) {
 			pw_log_debug("client %p: hide global %d", client, global->id);
 			pw_registry_resource_global_remove(resource, global->id);
 		}
-		else if (!PW_PERM_IS_R(old_permissions) && PW_PERM_IS_R(new_permissions)) {
+		else if (do_show) {
 			pw_log_debug("client %p: show global %d", client, global->id);
 			pw_registry_resource_global(resource,
 						    global->id,
@@ -363,6 +343,7 @@ int pw_global_update_permissions(struct pw_global *global, struct pw_client *cli
 						        &global->properties->dict : NULL);
 		}
 	}
+
 	spa_list_for_each_safe(resource, t, &global->resource_list, link) {
 		if (resource->client != client)
 			continue;