bus: introduce new SD_BUS_VTABLE_HIDDEN flag for vtable members

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

diff --git a/src/libsystemd-bus/bus-util.c b/src/libsystemd-bus/bus-util.c
index 4d73df5853c3f9f494d7054367a50569fd32dfab..0a3f6b85f5422796ba4a5f7747feefb742f6c8d3 100644 (file)
--- a/src/libsystemd-bus/bus-util.c
+++ b/src/libsystemd-bus/bus-util.c
@@ -20,6 +20,7 @@
 ***/
 
 #include <sys/socket.h>
+#include <sys/capability.h>
 
 #include "util.h"
 #include "strv.h"
@@ -65,7 +66,7 @@ int bus_async_unregister_and_quit(sd_event *e, sd_bus *bus, const char *name) {
         if (r < 0)
                 return r;
 
-        if (r != SD_BUS_NAME_RELEASED)
+        if (r != BUS_NAME_RELEASED)
                 return -EIO;
 
         return 0;
@@ -103,6 +104,32 @@ int bus_event_loop_with_idle(sd_event *e, sd_bus *bus, const char *name, usec_t
         return 0;
 }
 
+int bus_name_has_owner(sd_bus *c, const char *name, sd_bus_error *error) {
+        _cleanup_bus_message_unref_ sd_bus_message *rep = NULL;
+        int r, has_owner = 0;
+
+        assert(c);
+        assert(name);
+
+        r = sd_bus_call_method(c,
+                               "org.freedesktop.DBus",
+                               "/org/freedesktop/dbus",
+                               "org.freedesktop.DBus",
+                               "NameHasOwner",
+                               error,
+                               &rep,
+                               "s",
+                               name);
+        if (r < 0)
+                return r;
+
+        r = sd_bus_message_read_basic(rep, 'b', &has_owner);
+        if (r < 0)
+                return sd_bus_error_set_errno(error, r);
+
+        return has_owner;
+}
+
 int bus_verify_polkit(
                 sd_bus *bus,
                 sd_bus_message *m,
@@ -111,7 +138,7 @@ int bus_verify_polkit(
                 bool *_challenge,
                 sd_bus_error *e) {
 
-        const char *sender;
+        _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL;
         uid_t uid;
         int r;
 
@@ -119,11 +146,11 @@ int bus_verify_polkit(
         assert(m);
         assert(action);
 
-        sender = sd_bus_message_get_sender(m);
-        if (!sender)
-                return -EBADMSG;
+        r = sd_bus_query_sender_creds(m, SD_BUS_CREDS_UID, &creds);
+        if (r < 0)
+                return r;
 
-        r = sd_bus_get_owner_uid(bus, sender, &uid);
+        r = sd_bus_creds_get_uid(creds, &uid);
         if (r < 0)
                 return r;
 
@@ -134,6 +161,11 @@ int bus_verify_polkit(
         else {
                 _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
                 int authorized = false, challenge = false;
+                const char *sender;
+
+                sender = sd_bus_message_get_sender(m);
+                if (!sender)
+                        return -EBADMSG;
 
                 r = sd_bus_call_method(
                                 bus,
@@ -206,7 +238,6 @@ static void async_polkit_query_free(sd_bus *b, AsyncPolkitQuery *q) {
 
 static int async_polkit_callback(sd_bus *bus, sd_bus_message *reply, void *userdata, sd_bus_error *error) {
         _cleanup_bus_error_free_ sd_bus_error error_buffer = SD_BUS_ERROR_NULL;
-        _cleanup_bus_message_unref_ sd_bus_message *m = NULL;
         AsyncPolkitQuery *q = userdata;
         int r;
 
@@ -246,8 +277,9 @@ int bus_verify_polkit_async(
 #ifdef ENABLE_POLKIT
         _cleanup_bus_message_unref_ sd_bus_message *pk = NULL;
         AsyncPolkitQuery *q;
-#endif
         const char *sender;
+#endif
+        _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL;
         uid_t uid;
         int r;
 
@@ -294,17 +326,21 @@ int bus_verify_polkit_async(
         }
 #endif
 
-        sender = sd_bus_message_get_sender(m);
-        if (!sender)
-                return -EBADMSG;
+        r = sd_bus_query_sender_creds(m, SD_BUS_CREDS_UID, &creds);
+        if (r < 0)
+                return r;
 
-        r = sd_bus_get_owner_uid(bus, sender, &uid);
+        r = sd_bus_creds_get_uid(creds, &uid);
         if (r < 0)
                 return r;
 
         if (uid == 0)
                 return 1;
+
 #ifdef ENABLE_POLKIT
+        sender = sd_bus_message_get_sender(m);
+        if (!sender)
+                return -EBADMSG;
 
         r = hashmap_ensure_allocated(registry, trivial_hash_func, trivial_compare_func);
         if (r < 0)
@@ -403,21 +439,43 @@ int bus_open_system_systemd(sd_bus **_bus) {
         if (geteuid() != 0)
                 return sd_bus_open_system(_bus);
 
-        /* If we are root, then let's talk directly to the system
-         * instance, instead of going via the bus */
+        /* If we are root and kdbus is not available, then let's talk
+         * directly to the system instance, instead of going via the
+         * bus */
 
+#ifdef ENABLE_KDBUS
         r = sd_bus_new(&bus);
         if (r < 0)
                 return r;
 
-        r = sd_bus_set_address(bus, "unix:path=/run/systemd/private");
+        r = sd_bus_set_address(bus, "kernel:path=/dev/kdbus/0-system/bus");
         if (r < 0)
                 return r;
 
+        bus->bus_client = true;
+
         r = sd_bus_start(bus);
+        if (r >= 0) {
+                *_bus = bus;
+                bus = NULL;
+                return 0;
+        }
+
+        bus = sd_bus_unref(bus);
+#endif
+
+        r = sd_bus_new(&bus);
         if (r < 0)
                 return r;
 
+        r = sd_bus_set_address(bus, "unix:path=/run/systemd/private");
+        if (r < 0)
+                return r;
+
+        r = sd_bus_start(bus);
+        if (r < 0)
+                return sd_bus_open_system(_bus);
+
         r = bus_check_peercred(bus);
         if (r < 0)
                 return r;
@@ -430,33 +488,53 @@ int bus_open_system_systemd(sd_bus **_bus) {
 
 int bus_open_user_systemd(sd_bus **_bus) {
         _cleanup_bus_unref_ sd_bus *bus = NULL;
-        _cleanup_free_ char *p = NULL;
+        _cleanup_free_ char *ee = NULL;
         const char *e;
         int r;
 
-        /* If we are supposed to talk to the instance, try via
-         * XDG_RUNTIME_DIR first, then fallback to normal bus
-         * access */
+        /* Try via kdbus first, and then directly */
 
         assert(_bus);
 
-        e = secure_getenv("XDG_RUNTIME_DIR");
-        if (e) {
-                if (asprintf(&p, "unix:path=%s/systemd/private", e) < 0)
-                        return -ENOMEM;
-        }
-
+#ifdef ENABLE_KDBUS
         r = sd_bus_new(&bus);
         if (r < 0)
                 return r;
 
-        r = sd_bus_set_address(bus, p);
+        if (asprintf(&bus->address, "kernel:path=/dev/kdbus/%lu-user/bus", (unsigned long) getuid()) < 0)
+                return -ENOMEM;
+
+        bus->bus_client = true;
+
+        r = sd_bus_start(bus);
+        if (r >= 0) {
+                *_bus = bus;
+                bus = NULL;
+                return 0;
+        }
+
+        bus = sd_bus_unref(bus);
+#endif
+
+        e = secure_getenv("XDG_RUNTIME_DIR");
+        if (!e)
+                return sd_bus_open_system(_bus);
+
+        ee = bus_address_escape(e);
+        if (!ee)
+                return -ENOMEM;
+
+        r = sd_bus_new(&bus);
         if (r < 0)
                 return r;
 
+        bus->address = strjoin("unix:path=", ee, "/systemd/private", NULL);
+        if (!bus->address)
+                return -ENOMEM;
+
         r = sd_bus_start(bus);
         if (r < 0)
-                return r;
+                return sd_bus_open_system(_bus);
 
         r = bus_check_peercred(bus);
         if (r < 0)
@@ -1100,7 +1178,6 @@ int bus_maybe_reply_error(sd_bus_message *m, int r, sd_bus_error *error) {
         } else if (sd_bus_error_is_set(error)) {
                 if (m->header->type == SD_BUS_MESSAGE_METHOD_CALL)
                         sd_bus_reply_method_error(m, error);
-
         } else
                 return r;