bus: connect directly via kdbus in sd_bus_open_system_container()

[elogind.git] / src / libsystemd-bus / sd-bus.c

diff --git a/src/libsystemd-bus/sd-bus.c b/src/libsystemd-bus/sd-bus.c
index fef122bf3ede6a2740178e8ed655d052533e7151..edd917e30375786811727fd44590625e99ce3df1 100644 (file)
--- a/src/libsystemd-bus/sd-bus.c
+++ b/src/libsystemd-bus/sd-bus.c
@@ -318,6 +318,15 @@ _public_ int sd_bus_set_anonymous(sd_bus *bus, int b) {
         return 0;
 }
 
+_public_ int sd_bus_set_trusted(sd_bus *bus, int b) {
+        assert_return(bus, -EINVAL);
+        assert_return(bus->state == BUS_UNSET, -EPERM);
+        assert_return(!bus_pid_changed(bus), -ECHILD);
+
+        bus->trusted = !!b;
+        return 0;
+}
+
 static int hello_callback(sd_bus *bus, sd_bus_message *reply, void *userdata, sd_bus_error *error) {
         const char *s;
         int r;
@@ -755,6 +764,9 @@ static int parse_container_address(sd_bus *b, const char **p, char **guid) {
         if (!machine)
                 return -EINVAL;
 
+        if (!filename_is_safe(machine))
+                return -EINVAL;
+
         free(b->machine);
         b->machine = machine;
         machine = NULL;
@@ -1005,6 +1017,11 @@ _public_ int sd_bus_open_system(sd_bus **ret) {
 
         b->bus_client = true;
 
+        /* Let's do per-method access control on the system bus. We
+         * need the caller's UID and capability set for that. */
+        b->trusted = false;
+        b->attach_flags |= KDBUS_ATTACH_CAPS | KDBUS_ATTACH_CREDS;
+
         r = sd_bus_start(b);
         if (r < 0)
                 goto fail;
@@ -1065,6 +1082,10 @@ _public_ int sd_bus_open_user(sd_bus **ret) {
 
         b->bus_client = true;
 
+        /* We don't do any per-method access control on the user
+         * bus. */
+        b->trusted = true;
+
         r = sd_bus_start(b);
         if (r < 0)
                 goto fail;
@@ -1121,12 +1142,17 @@ _public_ int sd_bus_open_system_container(const char *machine, sd_bus **ret) {
 
         assert_return(machine, -EINVAL);
         assert_return(ret, -EINVAL);
+        assert_return(filename_is_safe(machine), -EINVAL);
 
         e = bus_address_escape(machine);
         if (!e)
                 return -ENOMEM;
 
+#ifdef ENABLE_KDBUS
+        p = strjoin("kernel:path=/dev/kdbus/ns/machine-", e, "/0-system/bus;x-container:machine=", e, NULL);
+#else
         p = strjoin("x-container:machine=", e, NULL);
+#endif
         if (!p)
                 return -ENOMEM;
 
@@ -1196,7 +1222,9 @@ _public_ sd_bus *sd_bus_ref(sd_bus *bus) {
 }
 
 _public_ sd_bus *sd_bus_unref(sd_bus *bus) {
-        assert_return(bus, NULL);
+
+        if (!bus)
+                return NULL;
 
         if (REFCNT_DEC(bus->n_ref) <= 0)
                 bus_free(bus);
@@ -2625,7 +2653,9 @@ fail:
 
 _public_ int sd_bus_detach_event(sd_bus *bus) {
         assert_return(bus, -EINVAL);
-        assert_return(bus->event, -ENXIO);
+
+        if (!bus->event)
+                return 0;
 
         if (bus->input_io_event_source) {
                 sd_event_source_set_enabled(bus->input_io_event_source, SD_EVENT_OFF);
@@ -2650,7 +2680,7 @@ _public_ int sd_bus_detach_event(sd_bus *bus) {
         if (bus->event)
                 bus->event = sd_event_unref(bus->event);
 
-        return 0;
+        return 1;
 }
 
 _public_ sd_event* sd_bus_get_event(sd_bus *bus) {