logind: when a bus call is done on a session, user or seat, optionally determine them from the caller credentials

More specifically, if an operation is requested on a session with an
empty name, the caller's session is used. If an operation is requested
on a seat with an empty name, the seat of the caller's session is used.
Finally, if an operation on the user with UID -1 is requested, the user
of the client's session is used (and not the UID of the client!).

1 files changed, 7 insertions, 8 deletions

diff --git a/src/login/logind-session-dbus.c b/src/login/logind-session-dbus.c
index a6b15f28a0..d3411314d8 100644
--- a/src/login/logind-session-dbus.c
+++ b/src/login/logind-session-dbus.c
@@ -490,23 +490,21 @@ int session_object_find(sd_bus *bus, const char *path, const char *interface, vo
         if (streq(path, "/org/freedesktop/login1/session/self")) {
                 _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL;
                 sd_bus_message *message;
-                pid_t pid;
+                const char *name;
 
                 message = sd_bus_get_current_message(bus);
                 if (!message)
                         return 0;
 
-                r = sd_bus_query_sender_creds(message, SD_BUS_CREDS_PID, &creds);
+                r = sd_bus_query_sender_creds(message, SD_BUS_CREDS_SESSION|SD_BUS_CREDS_AUGMENT, &creds);
                 if (r < 0)
                         return r;
 
-                r = sd_bus_creds_get_pid(creds, &pid);
+                r = sd_bus_creds_get_session(creds, &name);
                 if (r < 0)
                         return r;
 
-                r = manager_get_session_by_pid(m, pid, &session);
-                if (r <= 0)
-                        return 0;
+                session = hashmap_get(m->sessions, name);
         } else {
                 _cleanup_free_ char *e = NULL;
                 const char *p;
@@ -520,10 +518,11 @@ int session_object_find(sd_bus *bus, const char *path, const char *interface, vo
                         return -ENOMEM;
 
                 session = hashmap_get(m->sessions, e);
-                if (!session)
-                        return 0;
         }
 
+        if (!session)
+                return 0;
+
         *found = session;
         return 1;
 }