X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Flibsystemd%2Fsd-bus%2Fsd-bus.c;h=dc54e211a490b3918a400bc7c8eebfa5a0da780f;hb=93f1bcf40030a9e98bf2b71c177cbea36c64d5c9;hp=2794a4483fafeb83c98884e79761993e268960e0;hpb=03e334a1c7dc8c20c38902aa039440763acc9b17;p=elogind.git

diff --git a/src/libsystemd/sd-bus/sd-bus.c b/src/libsystemd/sd-bus/sd-bus.c
index 2794a4483..dc54e211a 100644
--- a/src/libsystemd/sd-bus/sd-bus.c
+++ b/src/libsystemd/sd-bus/sd-bus.c
@@ -111,6 +111,12 @@ static void bus_node_destroy(sd_bus *b, struct node *n) {
 static void bus_reset_queues(sd_bus *b) {
         assert(b);
 
+        /* NOTE: We _must_ decrement b->Xqueue_size before calling
+         * sd_bus_message_unref() for _each_ message. Otherwise the
+         * self-reference checks in sd_bus_unref() will fire for each message.
+         * We would thus recurse into sd_bus_message_unref() and trigger the
+         * assert(m->n_ref > 0) */
+
         while (b->rqueue_size > 0)
                 sd_bus_message_unref(b->rqueue[--b->rqueue_size]);
 
@@ -284,6 +290,15 @@ _public_ int sd_bus_set_bus_client(sd_bus *bus, int b) {
         return 0;
 }
 
+_public_ int sd_bus_set_monitor(sd_bus *bus, int b) {
+        assert_return(bus, -EINVAL);
+        assert_return(bus->state == BUS_UNSET, -EPERM);
+        assert_return(!bus_pid_changed(bus), -ECHILD);
+
+        SET_FLAG(bus->hello_flags, KDBUS_HELLO_MONITOR, b);
+        return 0;
+}
+
 _public_ int sd_bus_negotiate_fds(sd_bus *bus, int b) {
         assert_return(bus, -EINVAL);
         assert_return(bus->state == BUS_UNSET, -EPERM);
@@ -311,7 +326,7 @@ _public_ int sd_bus_negotiate_creds(sd_bus *bus, uint64_t mask) {
         /* The well knowns we need unconditionally, so that matches can work */
         bus->creds_mask = mask | SD_BUS_CREDS_WELL_KNOWN_NAMES|SD_BUS_CREDS_UNIQUE_NAME;
 
-        return kdbus_translate_attach_flags(bus->creds_mask, &bus->creds_mask);
+        return kdbus_translate_attach_flags(bus->creds_mask, &bus->attach_flags);
 }
 
 _public_ int sd_bus_set_server(sd_bus *bus, int b, sd_id128_t server_id) {
@@ -1075,7 +1090,7 @@ _public_ int sd_bus_open(sd_bus **ret) {
         if (e) {
                 if (streq(e, "system"))
                         return sd_bus_open_system(ret);
-                else if (streq(e, "session") || streq(e, "user"))
+                else if (STR_IN_SET(e, "session", "user"))
                         return sd_bus_open_user(ret);
         }
 
@@ -1114,8 +1129,18 @@ fail:
         return r;
 }
 
-_public_ int sd_bus_open_system(sd_bus **ret) {
+int bus_set_address_system(sd_bus *b) {
         const char *e;
+        assert(b);
+
+        e = secure_getenv("DBUS_SYSTEM_BUS_ADDRESS");
+        if (e)
+                return sd_bus_set_address(b, e);
+
+        return sd_bus_set_address(b, DEFAULT_SYSTEM_BUS_PATH);
+}
+
+_public_ int sd_bus_open_system(sd_bus **ret) {
         sd_bus *b;
         int r;
 
@@ -1125,11 +1150,7 @@ _public_ int sd_bus_open_system(sd_bus **ret) {
         if (r < 0)
                 return r;
 
-        e = secure_getenv("DBUS_SYSTEM_BUS_ADDRESS");
-        if (e)
-                r = sd_bus_set_address(b, e);
-        else
-                r = sd_bus_set_address(b, DEFAULT_SYSTEM_BUS_PATH);
+        r = bus_set_address_system(b);
         if (r < 0)
                 goto fail;
 
@@ -1153,53 +1174,56 @@ fail:
         return r;
 }
 
-_public_ int sd_bus_open_user(sd_bus **ret) {
+int bus_set_address_user(sd_bus *b) {
         const char *e;
-        sd_bus *b;
-        int r;
 
-        assert_return(ret, -EINVAL);
-
-        r = sd_bus_new(&b);
-        if (r < 0)
-                return r;
+        assert(b);
 
         e = secure_getenv("DBUS_SESSION_BUS_ADDRESS");
+        if (e)
+                return sd_bus_set_address(b, e);
+
+        e = secure_getenv("XDG_RUNTIME_DIR");
         if (e) {
-                r = sd_bus_set_address(b, e);
-                if (r < 0)
-                        goto fail;
-        } else {
-                e = secure_getenv("XDG_RUNTIME_DIR");
-                if (e) {
-                        _cleanup_free_ char *ee = NULL;
+                _cleanup_free_ char *ee = NULL;
 
-                        ee = bus_address_escape(e);
-                        if (!ee) {
-                                r = -ENOMEM;
-                                goto fail;
-                        }
+                ee = bus_address_escape(e);
+                if (!ee)
+                        return -ENOMEM;
 
 #ifdef ENABLE_KDBUS
-                        asprintf(&b->address, KERNEL_USER_BUS_FMT ";" UNIX_USER_BUS_FMT, (unsigned long) getuid(), ee);
+                asprintf(&b->address, KERNEL_USER_BUS_FMT ";" UNIX_USER_BUS_FMT, (unsigned long) getuid(), ee);
 #else
-                        asprintf(&b->address, UNIX_USER_BUS_FMT, ee);
+                asprintf(&b->address, UNIX_USER_BUS_FMT, ee);
 #endif
-                } else {
+        } else {
 #ifdef ENABLE_KDBUS
-                        asprintf(&b->address, KERNEL_USER_BUS_FMT, (unsigned long) getuid());
+                asprintf(&b->address, KERNEL_USER_BUS_FMT, (unsigned long) getuid());
 #else
-                        r = -ECONNREFUSED;
-                        goto fail;
+                return -ECONNREFUSED;
 #endif
-                }
-
-                if (!b->address) {
-                        r = -ENOMEM;
-                        goto fail;
-                }
         }
 
+        if (!b->address)
+                return -ENOMEM;
+
+        return 0;
+}
+
+_public_ int sd_bus_open_user(sd_bus **ret) {
+        sd_bus *b;
+        int r;
+
+        assert_return(ret, -EINVAL);
+
+        r = sd_bus_new(&b);
+        if (r < 0)
+                return r;
+
+        r = bus_set_address_user(b);
+        if (r < 0)
+                return r;
+
         b->bus_client = true;
         b->is_user = true;
 
@@ -1219,81 +1243,103 @@ fail:
         return r;
 }
 
-_public_ int sd_bus_open_system_remote(sd_bus **ret, const char *host) {
+int bus_set_address_system_remote(sd_bus *b, const char *host) {
         _cleanup_free_ char *e = NULL;
-        char *p = NULL;
-        sd_bus *bus;
-        int r;
 
-        assert_return(host, -EINVAL);
-        assert_return(ret, -EINVAL);
+        assert(b);
+        assert(host);
 
         e = bus_address_escape(host);
         if (!e)
                 return -ENOMEM;
 
-        p = strjoin("unixexec:path=ssh,argv1=-xT,argv2=", e, ",argv3=systemd-stdio-bridge", NULL);
-        if (!p)
+        b->address = strjoin("unixexec:path=ssh,argv1=-xT,argv2=", e, ",argv3=systemd-stdio-bridge", NULL);
+        if (!b->address)
                 return -ENOMEM;
 
+        return 0;
+ }
+
+_public_ int sd_bus_open_system_remote(sd_bus **ret, const char *host) {
+        sd_bus *bus;
+        int r;
+
+        assert_return(host, -EINVAL);
+        assert_return(ret, -EINVAL);
+
         r = sd_bus_new(&bus);
-        if (r < 0) {
-                free(p);
+        if (r < 0)
                 return r;
-        }
 
-        bus->address = p;
+        r = bus_set_address_system_remote(bus, host);
+        if (r < 0)
+                goto fail;
+
         bus->bus_client = true;
+        bus->trusted = false;
 
         r = sd_bus_start(bus);
-        if (r < 0) {
-                bus_free(bus);
-                return r;
-        }
+        if (r < 0)
+                goto fail;
 
         *ret = bus;
         return 0;
+
+fail:
+        bus_free(bus);
+        return r;
 }
 
-_public_ int sd_bus_open_system_container(sd_bus **ret, const char *machine) {
+int bus_set_address_system_container(sd_bus *b, const char *machine) {
         _cleanup_free_ char *e = NULL;
-        sd_bus *bus;
-        char *p;
-        int r;
 
-        assert_return(machine, -EINVAL);
-        assert_return(ret, -EINVAL);
-        assert_return(filename_is_safe(machine), -EINVAL);
+        assert(b);
+        assert(machine);
 
         e = bus_address_escape(machine);
         if (!e)
                 return -ENOMEM;
 
 #ifdef ENABLE_KDBUS
-        p = strjoin("x-container-kernel:machine=", e, ";x-container-unix:machine=", e, NULL);
+        b->address = strjoin("x-container-kernel:machine=", e, ";x-container-unix:machine=", e, NULL);
 #else
-        p = strjoin("x-container-unix:machine=", e, NULL);
+        b->address = strjoin("x-container-unix:machine=", e, NULL);
 #endif
-        if (!p)
+        if (!b->address)
                 return -ENOMEM;
 
+        return 0;
+}
+
+_public_ int sd_bus_open_system_container(sd_bus **ret, const char *machine) {
+        sd_bus *bus;
+        int r;
+
+        assert_return(machine, -EINVAL);
+        assert_return(ret, -EINVAL);
+        assert_return(filename_is_safe(machine), -EINVAL);
+
         r = sd_bus_new(&bus);
-        if (r < 0) {
-                free(p);
+        if (r < 0)
                 return r;
-        }
 
-        bus->address = p;
+        r = bus_set_address_system_container(bus, machine);
+        if (r < 0)
+                goto fail;
+
         bus->bus_client = true;
+        bus->trusted = false;
 
         r = sd_bus_start(bus);
-        if (r < 0) {
-                bus_free(bus);
-                return r;
-        }
+        if (r < 0)
+                goto fail;
 
         *ret = bus;
         return 0;
+
+fail:
+        bus_free(bus);
+        return r;
 }
 
 _public_ void sd_bus_close(sd_bus *bus) {
@@ -1348,6 +1394,24 @@ _public_ sd_bus *sd_bus_unref(sd_bus *bus) {
         if (!bus)
                 return NULL;
 
+        /* TODO/FIXME: It's naive to think REFCNT_GET() is thread-safe in any
+         * way but exclusive REFCNT_DEC(). The current logic _must_ lock around
+         * REFCNT_GET() until REFCNT_DEC() or two threads might end up in
+         * parallel in bus_reset_queues(). But locking would totally break the
+         * recursion we introduce by bus_reset_queues()...
+         * (Imagine one thread in sd_bus_message_unref() setting n_ref to 0 and
+         * thus calling into sd_bus_unref(). If at the same time the real
+         * thread calls sd_bus_unref(), both end up with "q == true" and will
+         * call into bus_reset_queues().
+         * If we require the main bus to be alive until all dispatch threads
+         * are done, there is no need to do ref-counts at all. So in both ways,
+         * the REFCNT thing is humbug.)
+         *
+         * On a second note: messages are *not* required to have ->bus set nor
+         * does it have to be _this_ bus that they're assigned to. This whole
+         * ref-cnt checking breaks apart if a message is not assigned to us.
+         * (which is _very_ easy to trigger with the current API). */
+
         if (REFCNT_GET(bus->n_ref) == bus->rqueue_size + bus->wqueue_size + 1) {
                 bool q = true;
 
@@ -1368,7 +1432,10 @@ _public_ sd_bus *sd_bus_unref(sd_bus *bus) {
                 /* We are the only holders on the messages, and the
                  * messages are the only holders on us, so let's drop
                  * the messages and thus implicitly also kill our own
-                 * last references */
+                 * last references.
+                 * bus_reset_queues() decrements the queue-size before
+                 * calling into sd_bus_message_unref(). Thus, it
+                 * protects us from recursion. */
 
                 if (q)
                         bus_reset_queues(bus);
@@ -1397,6 +1464,9 @@ _public_ int sd_bus_can_send(sd_bus *bus, char type) {
         assert_return(bus->state != BUS_UNSET, -ENOTCONN);
         assert_return(!bus_pid_changed(bus), -ECHILD);
 
+        if (bus->hello_flags & KDBUS_HELLO_MONITOR)
+                return 0;
+
         if (type == SD_BUS_TYPE_UNIX_FD) {
                 if (!(bus->hello_flags & KDBUS_HELLO_ACCEPT_FD))
                         return 0;
@@ -1595,9 +1665,12 @@ static int bus_send_internal(sd_bus *bus, sd_bus_message *_m, uint64_t *cookie,
         int r;
 
         assert_return(bus, -EINVAL);
-        assert_return(BUS_IS_OPEN(bus->state), -ENOTCONN);
         assert_return(m, -EINVAL);
         assert_return(!bus_pid_changed(bus), -ECHILD);
+        assert_return(!bus->is_kernel || !(bus->hello_flags & KDBUS_HELLO_MONITOR), -EROFS);
+
+        if (!BUS_IS_OPEN(bus->state))
+                return -ENOTCONN;
 
         if (m->n_fds > 0) {
                 r = sd_bus_can_send(bus, SD_BUS_TYPE_UNIX_FD);
@@ -1674,10 +1747,12 @@ _public_ int sd_bus_send_to(sd_bus *bus, sd_bus_message *m, const char *destinat
         int r;
 
         assert_return(bus, -EINVAL);
-        assert_return(BUS_IS_OPEN(bus->state), -ENOTCONN);
         assert_return(m, -EINVAL);
         assert_return(!bus_pid_changed(bus), -ECHILD);
 
+        if (!BUS_IS_OPEN(bus->state))
+                return -ENOTCONN;
+
         if (!streq_ptr(m->destination, destination)) {
 
                 if (!destination)
@@ -1729,12 +1804,15 @@ _public_ int sd_bus_call_async(
         int r;
 
         assert_return(bus, -EINVAL);
-        assert_return(BUS_IS_OPEN(bus->state), -ENOTCONN);
         assert_return(m, -EINVAL);
         assert_return(m->header->type == SD_BUS_MESSAGE_METHOD_CALL, -EINVAL);
         assert_return(!(m->header->flags & BUS_MESSAGE_NO_REPLY_EXPECTED), -EINVAL);
         assert_return(callback, -EINVAL);
         assert_return(!bus_pid_changed(bus), -ECHILD);
+        assert_return(!bus->is_kernel || !(bus->hello_flags & KDBUS_HELLO_MONITOR), -EROFS);
+
+        if (!BUS_IS_OPEN(bus->state))
+                return -ENOTCONN;
 
         r = hashmap_ensure_allocated(&bus->reply_callbacks, uint64_hash_func, uint64_compare_func);
         if (r < 0)
@@ -1842,12 +1920,15 @@ _public_ int sd_bus_call(
         int r;
 
         assert_return(bus, -EINVAL);
-        assert_return(BUS_IS_OPEN(bus->state), -ENOTCONN);
         assert_return(m, -EINVAL);
         assert_return(m->header->type == SD_BUS_MESSAGE_METHOD_CALL, -EINVAL);
         assert_return(!(m->header->flags & BUS_MESSAGE_NO_REPLY_EXPECTED), -EINVAL);
         assert_return(!bus_error_is_dirty(error), -EINVAL);
         assert_return(!bus_pid_changed(bus), -ECHILD);
+        assert_return(!bus->is_kernel || !(bus->hello_flags & KDBUS_HELLO_MONITOR), -EROFS);
+
+        if (!BUS_IS_OPEN(bus->state))
+                return -ENOTCONN;
 
         r = bus_ensure_running(bus);
         if (r < 0)
@@ -1885,12 +1966,17 @@ _public_ int sd_bus_call(
 
                                 if (incoming->header->type == SD_BUS_MESSAGE_METHOD_RETURN) {
 
-                                        if (reply)
-                                                *reply = incoming;
-                                        else
-                                                sd_bus_message_unref(incoming);
+                                        if (incoming->n_fds <= 0 || (bus->hello_flags & KDBUS_HELLO_ACCEPT_FD)) {
+                                                if (reply)
+                                                        *reply = incoming;
+                                                else
+                                                        sd_bus_message_unref(incoming);
+
+                                                return 1;
+                                        }
+
+                                        r = sd_bus_error_setf(error, SD_BUS_ERROR_INCONSISTENT_MESSAGE, "Reply message contained file descriptors which I couldn't accept. Sorry.");
 
-                                        return 1;
                                 } else if (incoming->header->type == SD_BUS_MESSAGE_METHOD_ERROR)
                                         r = sd_bus_error_copy(error, &incoming->error);
                                 else
@@ -1974,9 +2060,11 @@ _public_ int sd_bus_get_events(sd_bus *bus) {
         int flags = 0;
 
         assert_return(bus, -EINVAL);
-        assert_return(BUS_IS_OPEN(bus->state) || bus->state == BUS_CLOSING, -ENOTCONN);
         assert_return(!bus_pid_changed(bus), -ECHILD);
 
+        if (!BUS_IS_OPEN(bus->state) && bus->state != BUS_CLOSING)
+                return -ENOTCONN;
+
         if (bus->state == BUS_OPENING)
                 flags |= POLLOUT;
         else if (bus->state == BUS_AUTHENTICATING) {
@@ -2001,9 +2089,11 @@ _public_ int sd_bus_get_timeout(sd_bus *bus, uint64_t *timeout_usec) {
 
         assert_return(bus, -EINVAL);
         assert_return(timeout_usec, -EINVAL);
-        assert_return(BUS_IS_OPEN(bus->state) || bus->state == BUS_CLOSING, -ENOTCONN);
         assert_return(!bus_pid_changed(bus), -ECHILD);
 
+        if (!BUS_IS_OPEN(bus->state) && bus->state != BUS_CLOSING)
+                return -ENOTCONN;
+
         if (bus->track_queue) {
                 *timeout_usec = 0;
                 return 1;
@@ -2108,8 +2198,9 @@ static int process_hello(sd_bus *bus, sd_bus_message *m) {
 }
 
 static int process_reply(sd_bus *bus, sd_bus_message *m) {
+        _cleanup_bus_message_unref_ sd_bus_message *synthetic_reply = NULL;
         _cleanup_bus_error_free_ sd_bus_error error_buffer = SD_BUS_ERROR_NULL;
-        struct reply_callback *c;
+        _cleanup_free_ struct reply_callback *c = NULL;
         int r;
 
         assert(bus);
@@ -2119,6 +2210,12 @@ static int process_reply(sd_bus *bus, sd_bus_message *m) {
             m->header->type != SD_BUS_MESSAGE_METHOD_ERROR)
                 return 0;
 
+        if (bus->is_kernel && (bus->hello_flags & KDBUS_HELLO_MONITOR))
+                return 0;
+
+        if (m->destination && bus->unique_name && !streq_ptr(m->destination, bus->unique_name))
+                return 0;
+
         c = hashmap_remove(bus->reply_callbacks, &m->reply_cookie);
         if (!c)
                 return 0;
@@ -2126,13 +2223,32 @@ static int process_reply(sd_bus *bus, sd_bus_message *m) {
         if (c->timeout != 0)
                 prioq_remove(bus->reply_callbacks_prioq, c, &c->prioq_idx);
 
-        r = sd_bus_message_rewind(m, true);
-        if (r < 0)
-                return r;
+        if (m->n_fds > 0 && !(bus->hello_flags & KDBUS_HELLO_ACCEPT_FD)) {
+
+                /* If the reply contained a file descriptor which we
+                 * didn't want we pass an error instead. */
+
+                r = bus_message_new_synthetic_error(
+                                bus,
+                                m->reply_cookie,
+                                &SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_INCONSISTENT_MESSAGE, "Reply message contained file descriptor"),
+                                &synthetic_reply);
+                if (r < 0)
+                        return r;
+
+                r = bus_seal_synthetic_message(bus, synthetic_reply);
+                if (r < 0)
+                        return r;
+
+                m = synthetic_reply;
+        } else {
+                r = sd_bus_message_rewind(m, true);
+                if (r < 0)
+                        return r;
+        }
 
         r = c->callback(bus, m, c->userdata, &error_buffer);
         r = bus_maybe_reply_error(m, r, &error_buffer);
-        free(c);
 
         return r;
 }
@@ -2200,6 +2316,9 @@ static int process_builtin(sd_bus *bus, sd_bus_message *m) {
         assert(bus);
         assert(m);
 
+        if (bus->hello_flags & KDBUS_HELLO_MONITOR)
+                return 0;
+
         if (bus->manual_peer_interface)
                 return 0;
 
@@ -2244,6 +2363,32 @@ static int process_builtin(sd_bus *bus, sd_bus_message *m) {
         return 1;
 }
 
+static int process_fd_check(sd_bus *bus, sd_bus_message *m) {
+        assert(bus);
+        assert(m);
+
+        /* If we got a message with a file descriptor which we didn't
+         * want to accept, then let's drop it. How can this even
+         * happen? For example, when the kernel queues a message into
+         * an activatable names's queue which allows fds, and then is
+         * delivered to us later even though we ourselves did not
+         * negotiate it. */
+
+        if (bus->hello_flags & KDBUS_HELLO_MONITOR)
+                return 0;
+
+        if (m->n_fds <= 0)
+                return 0;
+
+        if (bus->hello_flags & KDBUS_HELLO_ACCEPT_FD)
+                return 0;
+
+        if (m->header->type != SD_BUS_MESSAGE_METHOD_CALL)
+                return 1; /* just eat it up */
+
+        return sd_bus_reply_method_errorf(m, SD_BUS_ERROR_INCONSISTENT_MESSAGE, "Message contains file descriptors, which I cannot accept. Sorry.");
+}
+
 static int process_message(sd_bus *bus, sd_bus_message *m) {
         int r;
 
@@ -2272,6 +2417,10 @@ static int process_message(sd_bus *bus, sd_bus_message *m) {
         if (r != 0)
                 goto finish;
 
+        r = process_fd_check(bus, m);
+        if (r != 0)
+                goto finish;
+
         r = process_filter(bus, m);
         if (r != 0)
                 goto finish;
@@ -2532,7 +2681,8 @@ static int bus_poll(sd_bus *bus, bool need_more, uint64_t timeout_usec) {
         if (bus->state == BUS_CLOSING)
                 return 1;
 
-        assert_return(BUS_IS_OPEN(bus->state), -ENOTCONN);
+        if (!BUS_IS_OPEN(bus->state))
+                return -ENOTCONN;
 
         e = sd_bus_get_events(bus);
         if (e < 0)
@@ -2587,7 +2737,8 @@ _public_ int sd_bus_wait(sd_bus *bus, uint64_t timeout_usec) {
         if (bus->state == BUS_CLOSING)
                 return 0;
 
-        assert_return(BUS_IS_OPEN(bus->state) , -ENOTCONN);
+        if (!BUS_IS_OPEN(bus->state))
+                return -ENOTCONN;
 
         if (bus->rqueue_size > 0)
                 return 0;
@@ -2604,7 +2755,8 @@ _public_ int sd_bus_flush(sd_bus *bus) {
         if (bus->state == BUS_CLOSING)
                 return 0;
 
-        assert_return(BUS_IS_OPEN(bus->state), -ENOTCONN);
+        if (!BUS_IS_OPEN(bus->state))
+                return -ENOTCONN;
 
         r = bus_ensure_running(bus);
         if (r < 0)
@@ -2913,7 +3065,7 @@ _public_ int sd_bus_attach_event(sd_bus *bus, sd_event *event, int priority) {
 
         bus->event_priority = priority;
 
-        r = sd_event_add_monotonic(bus->event, &bus->time_event_source, 0, 0, time_callback, bus);
+        r = sd_event_add_time(bus->event, &bus->time_event_source, CLOCK_MONOTONIC, 0, 0, time_callback, bus);
         if (r < 0)
                 goto fail;
 
@@ -2954,9 +3106,7 @@ _public_ int sd_bus_detach_event(sd_bus *bus) {
                 bus->quit_event_source = sd_event_source_unref(bus->quit_event_source);
         }
 
-        if (bus->event)
-                bus->event = sd_event_unref(bus->event);
-
+        bus->event = sd_event_unref(bus->event);
         return 1;
 }
 
@@ -3025,7 +3175,7 @@ _public_ int sd_bus_default(sd_bus **ret) {
         if (e) {
                 if (streq(e, "system"))
                         return sd_bus_default_system(ret);
-                else if (streq(e, "user") || streq(e, "session"))
+                else if (STR_IN_SET(e, "user", "session"))
                         return sd_bus_default_user(ret);
         }
 
@@ -3114,9 +3264,13 @@ _public_ int sd_bus_get_peer_creds(sd_bus *bus, uint64_t mask, sd_bus_creds **re
         assert_return(bus, -EINVAL);
         assert_return(mask <= _SD_BUS_CREDS_ALL, -ENOTSUP);
         assert_return(ret, -EINVAL);
-        assert_return(BUS_IS_OPEN(bus->state), -ENOTCONN);
         assert_return(!bus_pid_changed(bus), -ECHILD);
-        assert_return(!bus->is_kernel, -ENOTSUP);
+
+        if (bus->is_kernel)
+                return -ENOTSUP;
+
+        if (!BUS_IS_OPEN(bus->state))
+                return -ENOTCONN;
 
         if (!bus->ucred_valid && !isempty(bus->label))
                 return -ENODATA;
@@ -3155,9 +3309,13 @@ _public_ int sd_bus_try_close(sd_bus *bus) {
         int r;
 
         assert_return(bus, -EINVAL);
-        assert_return(BUS_IS_OPEN(bus->state), -ENOTCONN);
         assert_return(!bus_pid_changed(bus), -ECHILD);
-        assert_return(bus->is_kernel, -ENOTSUP);
+
+        if (!bus->is_kernel)
+                return -ENOTSUP;
+
+        if (!BUS_IS_OPEN(bus->state))
+                return -ENOTCONN;
 
         if (bus->rqueue_size > 0)
                 return -EBUSY;