chiark / gitweb /
bus: properly return an error when we detect a method call timeout
[elogind.git] / src / libsystemd-bus / bus-control.c
index 7cb7d44ae942a1ac74c4ea95c6e51f98b7484a4e..b9700068b6acaf20847c94e90e606c00556d8db5 100644 (file)
@@ -27,7 +27,6 @@
 #include <errno.h>
 
 #include "strv.h"
-
 #include "sd-bus.h"
 #include "bus-internal.h"
 #include "bus-message.h"
 _public_ int sd_bus_get_unique_name(sd_bus *bus, const char **unique) {
         int r;
 
-        if (!bus)
-                return -EINVAL;
-        if (!unique)
-                return -EINVAL;
-        if (bus_pid_changed(bus))
-                return -ECHILD;
+        assert_return(bus, -EINVAL);
+        assert_return(unique, -EINVAL);
+        assert_return(!bus_pid_changed(bus), -ECHILD);
 
         r = bus_ensure_running(bus);
         if (r < 0)
@@ -53,198 +49,503 @@ _public_ int sd_bus_get_unique_name(sd_bus *bus, const char **unique) {
         return 0;
 }
 
-_public_ int sd_bus_request_name(sd_bus *bus, const char *name, int flags) {
+static int bus_request_name_kernel(sd_bus *bus, const char *name, unsigned flags) {
+        struct kdbus_cmd_name *n;
+        size_t l;
+        int r;
+
+        assert(bus);
+        assert(name);
+
+        l = strlen(name);
+        n = alloca0(offsetof(struct kdbus_cmd_name, name) + l + 1);
+        n->size = offsetof(struct kdbus_cmd_name, name) + l + 1;
+        kdbus_translate_request_name_flags(flags, (uint64_t *) &n->flags);
+        memcpy(n->name, name, l+1);
+
+#ifdef HAVE_VALGRIND_MEMCHECK_H
+        VALGRIND_MAKE_MEM_DEFINED(n, n->size);
+#endif
+
+        r = ioctl(bus->input_fd, KDBUS_CMD_NAME_ACQUIRE, n);
+        if (r < 0)
+                return -errno;
+
+        if (n->flags & KDBUS_NAME_IN_QUEUE)
+                return 0;
+
+        return 1;
+}
+
+static int bus_request_name_dbus1(sd_bus *bus, const char *name, unsigned flags) {
         _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
         uint32_t ret;
         int r;
 
-        if (!bus)
-                return -EINVAL;
-        if (!name)
-                return -EINVAL;
-        if (!bus->bus_client)
-                return -EINVAL;
-        if (!BUS_IS_OPEN(bus->state))
-                return -ENOTCONN;
-        if (bus_pid_changed(bus))
-                return -ECHILD;
-
-        if (bus->is_kernel) {
-                struct kdbus_cmd_name *n;
-                size_t l;
-
-                l = strlen(name);
-                n = alloca0(offsetof(struct kdbus_cmd_name, name) + l + 1);
-                n->size = offsetof(struct kdbus_cmd_name, name) + l + 1;
-                n->flags = flags;
-                memcpy(n->name, name, l+1);
+        assert(bus);
+        assert(name);
+
+        r = sd_bus_call_method(
+                        bus,
+                        "org.freedesktop.DBus",
+                        "/",
+                        "org.freedesktop.DBus",
+                        "RequestName",
+                        NULL,
+                        &reply,
+                        "su",
+                        name,
+                        flags);
+        if (r < 0)
+                return r;
+
+        r = sd_bus_message_read(reply, "u", &ret);
+        if (r < 0)
+                return r;
+
+        if (ret == BUS_NAME_ALREADY_OWNER)
+                return -EALREADY;
+        else if (ret == BUS_NAME_EXISTS)
+                return -EEXIST;
+        else if (ret == BUS_NAME_IN_QUEUE)
+                return 0;
+        else if (ret == BUS_NAME_PRIMARY_OWNER)
+                return 1;
+
+        return -EIO;
+}
+
+_public_ int sd_bus_request_name(sd_bus *bus, const char *name, unsigned flags) {
+        assert_return(bus, -EINVAL);
+        assert_return(name, -EINVAL);
+        assert_return(bus->bus_client, -EINVAL);
+        assert_return(BUS_IS_OPEN(bus->state), -ENOTCONN);
+        assert_return(!bus_pid_changed(bus), -ECHILD);
+        assert_return(!(flags & ~(SD_BUS_NAME_ALLOW_REPLACEMENT|SD_BUS_NAME_REPLACE_EXISTING|SD_BUS_NAME_DO_NOT_QUEUE)), -EINVAL);
+
+        if (bus->is_kernel)
+                return bus_request_name_kernel(bus, name, flags);
+        else
+                return bus_request_name_dbus1(bus, name, flags);
+}
+
+static int bus_release_name_kernel(sd_bus *bus, const char *name) {
+        struct kdbus_cmd_name *n;
+        size_t l;
+        int r;
+
+        assert(bus);
+        assert(name);
+
+        l = strlen(name);
+        n = alloca0(offsetof(struct kdbus_cmd_name, name) + l + 1);
+        n->size = offsetof(struct kdbus_cmd_name, name) + l + 1;
+        memcpy(n->name, name, l+1);
 
 #ifdef HAVE_VALGRIND_MEMCHECK_H
-                VALGRIND_MAKE_MEM_DEFINED(n, n->size);
+        VALGRIND_MAKE_MEM_DEFINED(n, n->size);
 #endif
+        r = ioctl(bus->input_fd, KDBUS_CMD_NAME_RELEASE, n);
+        if (r < 0)
+                return -errno;
+
+        return n->flags;
+}
+
+static int bus_release_name_dbus1(sd_bus *bus, const char *name) {
+        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
+        uint32_t ret;
+        int r;
+
+        assert(bus);
+        assert(name);
+
+        r = sd_bus_call_method(
+                        bus,
+                        "org.freedesktop.DBus",
+                        "/",
+                        "org.freedesktop.DBus",
+                        "ReleaseName",
+                        NULL,
+                        &reply,
+                        "s",
+                        name);
+        if (r < 0)
+                return r;
+
+        r = sd_bus_message_read(reply, "u", &ret);
+        if (r < 0)
+                return r;
+        if (ret == BUS_NAME_NON_EXISTENT)
+                return -ENOENT;
+        if (ret == BUS_NAME_NOT_OWNER)
+                return -EADDRNOTAVAIL;
+        if (ret == BUS_NAME_RELEASED)
+                return 0;
+
+        return -EINVAL;
+}
+
+_public_ int sd_bus_release_name(sd_bus *bus, const char *name) {
+        assert_return(bus, -EINVAL);
+        assert_return(name, -EINVAL);
+        assert_return(bus->bus_client, -EINVAL);
+        assert_return(BUS_IS_OPEN(bus->state), -ENOTCONN);
+        assert_return(!bus_pid_changed(bus), -ECHILD);
+
+        if (bus->is_kernel)
+                return bus_release_name_kernel(bus, name);
+        else
+                return bus_release_name_dbus1(bus, name);
+}
+
+static int kernel_get_list(sd_bus *bus, uint64_t flags, char ***x) {
+        struct kdbus_cmd_name_list cmd = {};
+        struct kdbus_name_list *name_list;
+        struct kdbus_cmd_name *name;
+        uint64_t previous_id = 0;
+        int r;
+
+        /* Caller will free half-constructed list on failure... */
+
+        cmd.flags = flags;
+
+        r = ioctl(bus->input_fd, KDBUS_CMD_NAME_LIST, &cmd);
+        if (r < 0)
+                return -errno;
+
+        name_list = (struct kdbus_name_list *) ((uint8_t *) bus->kdbus_buffer + cmd.offset);
+
+        KDBUS_ITEM_FOREACH(name, name_list, names) {
+
+                if ((flags & KDBUS_NAME_LIST_UNIQUE) && name->id != previous_id) {
+                        char *n;
+
+                        if (asprintf(&n, ":1.%llu", (unsigned long long) name->id) < 0)
+                                return -ENOMEM;
+
+                        r = strv_push(x, n);
+                        if (r < 0) {
+                                free(n);
+                                return -ENOMEM;
+                        }
+
+                        previous_id = name->id;
+                }
+
+                if (name->size > sizeof(*name)) {
+                        r = strv_extend(x, name->name);
+                        if (r < 0)
+                                return -ENOMEM;
+                }
+        }
+
+        r = ioctl(sd_bus_get_fd(bus), KDBUS_CMD_FREE, &cmd.offset);
+        if (r < 0)
+                return -errno;
+
+        return 0;
+}
+
+static int bus_list_names_kernel(sd_bus *bus, char ***acquired, char ***activatable) {
+        _cleanup_strv_free_ char **x = NULL, **y = NULL;
+        int r;
 
-                r = ioctl(bus->input_fd, KDBUS_CMD_NAME_ACQUIRE, n);
+        if (acquired) {
+                r = kernel_get_list(bus, KDBUS_NAME_LIST_UNIQUE | KDBUS_NAME_LIST_NAMES, &x);
                 if (r < 0)
-                        return -errno;
+                        return r;
+        }
 
-                return n->flags;
-        } else {
+        if (activatable) {
+                r = kernel_get_list(bus, KDBUS_NAME_LIST_STARTERS, &y);
+                if (r < 0)
+                        return r;
+
+                *activatable = y;
+                y = NULL;
+        }
+
+        if (acquired) {
+                *acquired = x;
+                x = NULL;
+        }
+
+        return 0;
+}
+
+static int bus_list_names_dbus1(sd_bus *bus, char ***acquired, char ***activatable) {
+        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
+        _cleanup_strv_free_ char **x = NULL, **y = NULL;
+        int r;
+
+        if (acquired) {
                 r = sd_bus_call_method(
                                 bus,
                                 "org.freedesktop.DBus",
                                 "/",
                                 "org.freedesktop.DBus",
-                                "RequestName",
+                                "ListNames",
                                 NULL,
                                 &reply,
-                                "su",
-                                name,
-                                flags);
+                                NULL);
                 if (r < 0)
                         return r;
 
-                r = sd_bus_message_read(reply, "u", &ret);
+                r = sd_bus_message_read_strv(reply, &x);
                 if (r < 0)
                         return r;
 
-                return ret;
+                reply = sd_bus_message_unref(reply);
         }
-}
 
-_public_ int sd_bus_release_name(sd_bus *bus, const char *name) {
-        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
-        uint32_t ret;
-        int r;
-
-        if (!bus)
-                return -EINVAL;
-        if (!name)
-                return -EINVAL;
-        if (!bus->bus_client)
-                return -EINVAL;
-        if (!BUS_IS_OPEN(bus->state))
-                return -ENOTCONN;
-        if (bus_pid_changed(bus))
-                return -ECHILD;
-
-        if (bus->is_kernel) {
-                struct kdbus_cmd_name *n;
-                size_t l;
-
-                l = strlen(name);
-                n = alloca0(offsetof(struct kdbus_cmd_name, name) + l + 1);
-                n->size = offsetof(struct kdbus_cmd_name, name) + l + 1;
-                memcpy(n->name, name, l+1);
-
-#ifdef HAVE_VALGRIND_MEMCHECK_H
-                VALGRIND_MAKE_MEM_DEFINED(n, n->size);
-#endif
-                r = ioctl(bus->input_fd, KDBUS_CMD_NAME_RELEASE, n);
-                if (r < 0)
-                        return -errno;
-
-                return n->flags;
-        } else {
+        if (activatable) {
                 r = sd_bus_call_method(
                                 bus,
                                 "org.freedesktop.DBus",
                                 "/",
                                 "org.freedesktop.DBus",
-                                "ReleaseName",
+                                "ListActivatableNames",
                                 NULL,
                                 &reply,
-                                "s",
-                                name);
+                                NULL);
                 if (r < 0)
                         return r;
 
-                r = sd_bus_message_read(reply, "u", &ret);
+                r = sd_bus_message_read_strv(reply, &y);
                 if (r < 0)
                         return r;
+
+                *activatable = y;
+                y = NULL;
         }
 
-        return ret;
+        if (acquired) {
+                *acquired = x;
+                x = NULL;
+        }
+
+        return 0;
 }
 
-_public_ int sd_bus_list_names(sd_bus *bus, char ***l) {
-        _cleanup_bus_message_unref_ sd_bus_message *reply1 = NULL, *reply2 = NULL;
-        char **x = NULL;
-        int r;
+_public_ int sd_bus_list_names(sd_bus *bus, char ***acquired, char ***activatable) {
+        assert_return(bus, -EINVAL);
+        assert_return(acquired || activatable, -EINVAL);
+        assert_return(BUS_IS_OPEN(bus->state), -ENOTCONN);
+        assert_return(!bus_pid_changed(bus), -ECHILD);
 
-        if (!bus)
-                return -EINVAL;
-        if (!l)
-                return -EINVAL;
-        if (!BUS_IS_OPEN(bus->state))
-                return -ENOTCONN;
-        if (bus_pid_changed(bus))
-                return -ECHILD;
+        if (bus->is_kernel)
+                return bus_list_names_kernel(bus, acquired, activatable);
+        else
+                return bus_list_names_dbus1(bus, acquired, activatable);
+}
 
-        r = sd_bus_call_method(
-                        bus,
-                        "org.freedesktop.DBus",
-                        "/",
-                        "org.freedesktop.DBus",
-                        "ListNames",
-                        NULL,
-                        &reply1,
-                        NULL);
+static int bus_get_owner_kdbus(
+                sd_bus *bus,
+                const char *name,
+                uint64_t mask,
+                sd_bus_creds **creds) {
+
+        _cleanup_bus_creds_unref_ sd_bus_creds *c = NULL;
+        struct kdbus_cmd_conn_info *cmd;
+        struct kdbus_conn_info *conn_info;
+        struct kdbus_item *item;
+        size_t size;
+        uint64_t m, id;
+        int r;
+
+        r = bus_kernel_parse_unique_name(name, &id);
         if (r < 0)
                 return r;
+        if (r > 0) {
+                size = offsetof(struct kdbus_cmd_conn_info, name);
+                cmd = alloca0(size);
+                cmd->id = id;
+        } else {
+                size = offsetof(struct kdbus_cmd_conn_info, name) + strlen(name) + 1;
+                cmd = alloca0(size);
+                strcpy(cmd->name, name);
+        }
+        cmd->flags = KDBUS_ATTACH_NAMES;
 
-        r = sd_bus_call_method(
-                        bus,
-                        "org.freedesktop.DBus",
-                        "/",
-                        "org.freedesktop.DBus",
-                        "ListActivatableNames",
-                        NULL,
-                        &reply2,
-                        NULL);
+        cmd->size = size;
+        r = ioctl(bus->input_fd, KDBUS_CMD_CONN_INFO, cmd);
         if (r < 0)
-                return r;
+                return -errno;
 
-        r = bus_message_read_strv_extend(reply1, &x);
-        if (r < 0) {
-                strv_free(x);
-                return r;
+        conn_info = (struct kdbus_conn_info *) ((uint8_t *) bus->kdbus_buffer + cmd->offset);
+
+        c = bus_creds_new();
+        if (!c)
+                return -ENOMEM;
+
+        if (mask & SD_BUS_CREDS_UNIQUE_NAME) {
+                if (asprintf(&c->unique_name, ":1.%llu", (unsigned long long) conn_info->id) < 0)
+                        return -ENOMEM;
+
+                c->mask |= SD_BUS_CREDS_UNIQUE_NAME;
         }
 
-        r = bus_message_read_strv_extend(reply2, &x);
-        if (r < 0) {
-                strv_free(x);
-                return r;
+        KDBUS_ITEM_FOREACH(item, conn_info, items) {
+
+                switch (item->type) {
+
+                case KDBUS_ITEM_CREDS:
+                        m = (SD_BUS_CREDS_UID | SD_BUS_CREDS_GID | SD_BUS_CREDS_PID |
+                             SD_BUS_CREDS_TID | SD_BUS_CREDS_PID_STARTTIME) & mask;
+
+                        if (m) {
+                                c->uid = item->creds.uid;
+                                c->pid = item->creds.pid;
+                                c->gid = item->creds.gid;
+                                c->tid = item->creds.tid;
+                                c->pid_starttime = item->creds.starttime;
+                                c->mask |= m;
+                        }
+                        break;
+
+                case KDBUS_ITEM_PID_COMM:
+                        if (mask & SD_BUS_CREDS_COMM) {
+                                c->comm = strdup(item->str);
+                                if (!c->comm) {
+                                        r = -ENOMEM;
+                                        goto fail;
+                                }
+
+                                c->mask |= SD_BUS_CREDS_COMM;
+                        }
+                        break;
+
+                case KDBUS_ITEM_TID_COMM:
+                        if (mask & SD_BUS_CREDS_TID_COMM) {
+                                c->tid_comm = strdup(item->str);
+                                if (!c->tid_comm) {
+                                        r = -ENOMEM;
+                                        goto fail;
+                                }
+
+                                c->mask |= SD_BUS_CREDS_TID_COMM;
+                        }
+                        break;
+
+                case KDBUS_ITEM_EXE:
+                        if (mask & SD_BUS_CREDS_EXE) {
+                                c->exe = strdup(item->str);
+                                if (!c->exe) {
+                                        r = -ENOMEM;
+                                        goto fail;
+                                }
+
+                                c->mask |= SD_BUS_CREDS_EXE;
+                        }
+                        break;
+
+                case KDBUS_ITEM_CMDLINE:
+                        if (mask & SD_BUS_CREDS_CMDLINE) {
+                                c->cmdline_size = item->size - KDBUS_ITEM_HEADER_SIZE;
+                                c->cmdline = memdup(item->data, c->cmdline_size);
+                                if (!c->cmdline) {
+                                        r = -ENOMEM;
+                                        goto fail;
+                                }
+
+                                c->mask |= SD_BUS_CREDS_CMDLINE;
+                        }
+                        break;
+
+                case KDBUS_ITEM_CGROUP:
+                        m = (SD_BUS_CREDS_CGROUP | SD_BUS_CREDS_UNIT |
+                             SD_BUS_CREDS_USER_UNIT | SD_BUS_CREDS_SLICE |
+                             SD_BUS_CREDS_SESSION | SD_BUS_CREDS_OWNER_UID) & mask;
+
+                        if (m) {
+                                c->cgroup = strdup(item->str);
+                                if (!c->cgroup) {
+                                        r = -ENOMEM;
+                                        goto fail;
+                                }
+
+                                c->mask |= m;
+                        }
+                        break;
+
+                case KDBUS_ITEM_CAPS:
+                        m = (SD_BUS_CREDS_EFFECTIVE_CAPS | SD_BUS_CREDS_PERMITTED_CAPS |
+                             SD_BUS_CREDS_INHERITABLE_CAPS | SD_BUS_CREDS_BOUNDING_CAPS) & mask;
+
+                        if (m) {
+                                c->capability_size = item->size - KDBUS_ITEM_HEADER_SIZE;
+                                c->capability = memdup(item->data, c->capability_size);
+                                if (!c->capability) {
+                                        r = -ENOMEM;
+                                        goto fail;
+                                }
+
+                                c->mask |= m;
+                        }
+                        break;
+
+                case KDBUS_ITEM_SECLABEL:
+                        if (mask & SD_BUS_CREDS_SELINUX_CONTEXT) {
+                                c->label = strdup(item->str);
+                                if (!c->label) {
+                                        r = -ENOMEM;
+                                        goto fail;
+                                }
+
+                                c->mask |= SD_BUS_CREDS_SELINUX_CONTEXT;
+                        }
+                        break;
+
+                case KDBUS_ITEM_AUDIT:
+                        m = (SD_BUS_CREDS_AUDIT_SESSION_ID | SD_BUS_CREDS_AUDIT_LOGIN_UID) & mask;
+
+                        if (m) {
+                                c->audit_session_id = item->audit.sessionid;
+                                c->audit_login_uid = item->audit.loginuid;
+                                c->mask |= m;
+                        }
+                        break;
+
+                case KDBUS_ITEM_NAME:
+                        if (mask & SD_BUS_CREDS_WELL_KNOWN_NAMES) {
+                                r = strv_extend(&c->well_known_names, item->name.name);
+                                if (r < 0)
+                                        goto fail;
+
+                                c->mask |= SD_BUS_CREDS_WELL_KNOWN_NAMES;
+                        }
+                        break;
+                }
         }
 
-        *l = strv_uniq(x);
-        return 0;
+        if (creds) {
+                *creds = c;
+                c = NULL;
+        }
+
+        r = 0;
+
+fail:
+        ioctl(bus->input_fd, KDBUS_CMD_FREE, &cmd->offset);
+        return r;
 }
 
-_public_ int sd_bus_get_owner(
+static int bus_get_owner_dbus1(
                 sd_bus *bus,
                 const char *name,
                 uint64_t mask,
-                char **owner,
                 sd_bus_creds **creds) {
 
-        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
+        _cleanup_bus_message_unref_ sd_bus_message *reply_unique = NULL, *reply = NULL;
         _cleanup_bus_creds_unref_ sd_bus_creds *c = NULL;
-        _cleanup_free_ char *unique = NULL;
+        const char *unique = NULL;
         pid_t pid = 0;
         int r;
 
-        assert_return(bus, -EINVAL);
-        assert_return(name, -EINVAL);
-        assert_return(mask <= _SD_BUS_CREDS_MAX, -ENOTSUP);
-        assert_return(mask == 0 || creds, -EINVAL);
-        assert_return(BUS_IS_OPEN(bus->state), -ENOTCONN);
-        assert_return(!bus_pid_changed(bus), -ECHILD);
-
         /* Only query the owner if the caller wants to know it or if
          * the caller just wants to check whether a name exists */
-        if (owner || mask == 0) {
-                const char *found;
-
+        if ((mask & SD_BUS_CREDS_UNIQUE_NAME) || mask == 0) {
                 r = sd_bus_call_method(
                                 bus,
                                 "org.freedesktop.DBus",
@@ -252,21 +553,15 @@ _public_ int sd_bus_get_owner(
                                 "org.freedesktop.DBus",
                                 "GetNameOwner",
                                 NULL,
-                                &reply,
+                                &reply_unique,
                                 "s",
                                 name);
                 if (r < 0)
                         return r;
 
-                r = sd_bus_message_read(reply, "s", &found);
+                r = sd_bus_message_read(reply_unique, "s", &unique);
                 if (r < 0)
                         return r;
-
-                unique = strdup(found);
-                if (!unique)
-                        return -ENOMEM;
-
-                reply = sd_bus_message_unref(reply);
         }
 
         if (mask != 0) {
@@ -274,8 +569,19 @@ _public_ int sd_bus_get_owner(
                 if (!c)
                         return -ENOMEM;
 
-                if ((mask & SD_BUS_CREDS_PID) ||
-                    mask & ~(SD_BUS_CREDS_PID|SD_BUS_CREDS_UID|SD_BUS_CREDS_SELINUX_CONTEXT)) {
+                if ((mask & SD_BUS_CREDS_UNIQUE_NAME) && unique) {
+                        c->unique_name = strdup(unique);
+                        if (!c->unique_name)
+                                return -ENOMEM;
+
+                        c->mask |= SD_BUS_CREDS_UNIQUE_NAME;
+                }
+
+                if (mask & (SD_BUS_CREDS_PID|SD_BUS_CREDS_PID_STARTTIME|SD_BUS_CREDS_GID|
+                            SD_BUS_CREDS_COMM|SD_BUS_CREDS_EXE|SD_BUS_CREDS_CMDLINE|
+                            SD_BUS_CREDS_CGROUP|SD_BUS_CREDS_UNIT|SD_BUS_CREDS_USER_UNIT|SD_BUS_CREDS_SLICE|SD_BUS_CREDS_SESSION|SD_BUS_CREDS_OWNER_UID|
+                            SD_BUS_CREDS_EFFECTIVE_CAPS|SD_BUS_CREDS_PERMITTED_CAPS|SD_BUS_CREDS_INHERITABLE_CAPS|SD_BUS_CREDS_BOUNDING_CAPS|
+                            SD_BUS_CREDS_AUDIT_SESSION_ID|SD_BUS_CREDS_AUDIT_LOGIN_UID)) {
                         uint32_t u;
 
                         r = sd_bus_call_method(
@@ -287,7 +593,7 @@ _public_ int sd_bus_get_owner(
                                         NULL,
                                         &reply,
                                         "s",
-                                        name);
+                                        unique ? unique : name);
                         if (r < 0)
                                 return r;
 
@@ -316,7 +622,7 @@ _public_ int sd_bus_get_owner(
                                         NULL,
                                         &reply,
                                         "s",
-                                        name);
+                                        unique ? unique : name);
                         if (r < 0)
                                 return r;
 
@@ -343,7 +649,7 @@ _public_ int sd_bus_get_owner(
                                         NULL,
                                         &reply,
                                         "s",
-                                        name);
+                                        unique ? unique : name);
                         if (r < 0)
                                 return r;
 
@@ -368,209 +674,461 @@ _public_ int sd_bus_get_owner(
                 c = NULL;
         }
 
-        if (owner) {
-                *owner = unique;
-                unique = NULL;
+        return 0;
+}
+
+_public_ int sd_bus_get_owner(
+                sd_bus *bus,
+                const char *name,
+                uint64_t mask,
+                sd_bus_creds **creds) {
+
+        assert_return(bus, -EINVAL);
+        assert_return(name, -EINVAL);
+        assert_return(mask <= _SD_BUS_CREDS_ALL, -ENOTSUP);
+        assert_return(mask == 0 || creds, -EINVAL);
+        assert_return(BUS_IS_OPEN(bus->state), -ENOTCONN);
+        assert_return(!bus_pid_changed(bus), -ECHILD);
+
+        if (bus->is_kernel)
+                return bus_get_owner_kdbus(bus, name, mask, creds);
+        else
+                return bus_get_owner_dbus1(bus, name, mask, creds);
+}
+
+static int add_name_change_match(sd_bus *bus,
+                                 uint64_t cookie,
+                                 const char *name,
+                                 const char *old_owner,
+                                 const char *new_owner) {
+
+        uint64_t name_id = 0, old_owner_id = 0, new_owner_id = 0;
+        int is_name_id = -1, r;
+        struct kdbus_item *item;
+
+        assert(bus);
+
+        /* If we encounter a match that could match against
+         * NameOwnerChanged messages, then we need to create
+         * KDBUS_MATCH_NAME_{ADD,REMOVE,CHANGE} and
+         * KDBUS_MATCH_ID_{ADD,REMOVE} matches for it, possibly
+         * multiple if the match is underspecified.
+         *
+         * The NameOwnerChanged signals take three parameters with
+         * unique or well-known names, but only some forms actually
+         * exist:
+         *
+         * WELLKNOWN, "", UNIQUE       â†’ KDBUS_MATCH_NAME_ADD
+         * WELLKNOWN, UNIQUE, ""       â†’ KDBUS_MATCH_NAME_REMOVE
+         * WELLKNOWN, UNIQUE, UNIQUE   â†’ KDBUS_MATCH_NAME_CHANGE
+         * UNIQUE, "", UNIQUE          â†’ KDBUS_MATCH_ID_ADD
+         * UNIQUE, UNIQUE, ""          â†’ KDBUS_MATCH_ID_REMOVE
+         *
+         * For the latter two the two unique names must be identical.
+         *
+         * */
+
+        if (name) {
+                is_name_id = bus_kernel_parse_unique_name(name, &name_id);
+                if (is_name_id < 0)
+                        return 0;
+        }
+
+        if (old_owner) {
+                r = bus_kernel_parse_unique_name(old_owner, &old_owner_id);
+                if (r < 0)
+                        return 0;
+                if (r == 0)
+                        return 0;
+                if (is_name_id > 0 && old_owner_id != name_id)
+                        return 0;
+        }
+
+        if (new_owner) {
+                r = bus_kernel_parse_unique_name(new_owner, &new_owner_id);
+                if (r < 0)
+                        return r;
+                if (r == 0)
+                        return 0;
+                if (is_name_id > 0 && new_owner_id != name_id)
+                        return 0;
+        }
+
+        if (is_name_id <= 0) {
+                struct kdbus_cmd_match *m;
+                size_t sz, l;
+
+                /* If the name argument is missing or is a well-known
+                 * name, then add KDBUS_MATCH_NAME_{ADD,REMOVE,CHANGE}
+                 * matches for it */
+
+                l = name ? strlen(name) : 0;
+
+                sz = ALIGN8(offsetof(struct kdbus_cmd_match, items) +
+                            offsetof(struct kdbus_item, name_change) +
+                            offsetof(struct kdbus_notify_name_change, name) +
+                            l+1);
+
+                m = alloca0(sz);
+                m->size = sz;
+                m->cookie = cookie;
+                m->src_id = KDBUS_SRC_ID_KERNEL;
+
+                item = m->items;
+                item->size =
+                        offsetof(struct kdbus_item, name_change) +
+                        offsetof(struct kdbus_notify_name_change, name) +
+                        l+1;
+
+                item->name_change.old_id = old_owner_id;
+                item->name_change.new_id = new_owner_id;
+
+                if (name)
+                        strcpy(item->name_change.name, name);
+
+                /* If the old name is unset or empty, then
+                 * this can match against added names */
+                if (!old_owner || old_owner[0] == 0) {
+                        item->type = KDBUS_MATCH_NAME_ADD;
+
+                        r = ioctl(bus->input_fd, KDBUS_CMD_MATCH_ADD, m);
+                        if (r < 0)
+                                return -errno;
+                }
+
+                /* If the new name is unset or empty, then
+                 * this can match against removed names */
+                if (!new_owner || new_owner[0] == 0) {
+                        item->type = KDBUS_MATCH_NAME_REMOVE;
+
+                        r = ioctl(bus->input_fd, KDBUS_CMD_MATCH_ADD, m);
+                        if (r < 0)
+                                return -errno;
+                }
+
+                /* If the neither name is explicitly set to
+                 * the empty string, then this can match
+                 * agains changed names */
+                if (!(old_owner && old_owner[0] == 0) &&
+                    !(new_owner && new_owner[0] == 0)) {
+                        item->type = KDBUS_MATCH_NAME_CHANGE;
+
+                        r = ioctl(bus->input_fd, KDBUS_CMD_MATCH_ADD, m);
+                        if (r < 0)
+                                return -errno;
+                }
+        }
+
+        if (is_name_id != 0) {
+                struct kdbus_cmd_match *m;
+                uint64_t sz;
+
+                /* If the name argument is missing or is a unique
+                 * name, then add KDBUS_MATCH_ID_{ADD,REMOVE} matches
+                 * for it */
+
+                sz = ALIGN8(offsetof(struct kdbus_cmd_match, items) +
+                            offsetof(struct kdbus_item, id_change) +
+                            sizeof(struct kdbus_notify_id_change));
+
+                m = alloca0(sz);
+                m->size = sz;
+                m->cookie = cookie;
+                m->src_id = KDBUS_SRC_ID_KERNEL;
+
+                item = m->items;
+                item->size = offsetof(struct kdbus_item, id_change) + sizeof(struct kdbus_notify_id_change);
+                item->id_change.id = name_id;
+
+                /* If the old name is unset or empty, then this can
+                 * match against added ids */
+                if (!old_owner || old_owner[0] == 0) {
+                        item->type = KDBUS_MATCH_ID_ADD;
+
+                        r = ioctl(bus->input_fd, KDBUS_CMD_MATCH_ADD, m);
+                        if (r < 0)
+                                return -errno;
+                }
+
+                /* If thew new name is unset or empty, then this can
+                match against removed ids */
+                if (!new_owner || new_owner[0] == 0) {
+                        item->type = KDBUS_MATCH_ID_REMOVE;
+
+                        r = ioctl(bus->input_fd, KDBUS_CMD_MATCH_ADD, m);
+                        if (r < 0)
+                                return -errno;
+                }
         }
 
         return 0;
 }
 
-int bus_add_match_internal(
+static int bus_add_match_internal_kernel(
                 sd_bus *bus,
                 const char *match,
                 struct bus_match_component *components,
                 unsigned n_components,
                 uint64_t cookie) {
 
+        struct kdbus_cmd_match *m;
+        struct kdbus_item *item;
+        uint64_t bloom[BLOOM_SIZE/8];
+        size_t sz;
+        const char *sender = NULL;
+        size_t sender_length = 0;
+        uint64_t src_id = KDBUS_MATCH_SRC_ID_ANY;
+        bool using_bloom = false;
+        unsigned i;
+        bool matches_name_change = true;
+        const char *name_change_arg[3] = {};
         int r;
 
         assert(bus);
         assert(match);
 
-        if (bus->is_kernel) {
-                struct kdbus_cmd_match *m;
-                struct kdbus_item *item;
-                uint64_t bloom[BLOOM_SIZE/8];
-                size_t sz;
-                const char *sender = NULL;
-                size_t sender_length = 0;
-                uint64_t src_id = KDBUS_MATCH_SRC_ID_ANY;
-                bool using_bloom = false;
-                unsigned i;
+        zero(bloom);
 
-                zero(bloom);
+        sz = offsetof(struct kdbus_cmd_match, items);
 
-                sz = offsetof(struct kdbus_cmd_match, items);
+        for (i = 0; i < n_components; i++) {
+                struct bus_match_component *c = &components[i];
 
-                for (i = 0; i < n_components; i++) {
-                        struct bus_match_component *c = &components[i];
+                switch (c->type) {
 
-                        switch (c->type) {
+                case BUS_MATCH_SENDER:
+                        if (!streq(c->value_str, "org.freedesktop.DBus"))
+                                matches_name_change = false;
 
-                        case BUS_MATCH_SENDER:
-                                r = bus_kernel_parse_unique_name(c->value_str, &src_id);
-                                if (r < 0)
-                                        return r;
+                        r = bus_kernel_parse_unique_name(c->value_str, &src_id);
+                        if (r < 0)
+                                return r;
 
-                                if (r > 0) {
-                                        sender = c->value_str;
-                                        sender_length = strlen(sender);
-                                        sz += ALIGN8(offsetof(struct kdbus_item, str) + sender_length + 1);
-                                }
+                        if (r > 0) {
+                                sender = c->value_str;
+                                sender_length = strlen(sender);
+                                sz += ALIGN8(offsetof(struct kdbus_item, str) + sender_length + 1);
+                        }
 
-                                break;
+                        break;
 
-                        case BUS_MATCH_MESSAGE_TYPE:
-                                bloom_add_pair(bloom, "message-type", bus_message_type_to_string(c->value_u8));
-                                using_bloom = true;
-                                break;
+                case BUS_MATCH_MESSAGE_TYPE:
+                        if (c->value_u8 != SD_BUS_MESSAGE_SIGNAL)
+                                matches_name_change = false;
 
-                        case BUS_MATCH_INTERFACE:
-                                bloom_add_pair(bloom, "interface", c->value_str);
-                                using_bloom = true;
-                                break;
+                        bloom_add_pair(bloom, "message-type", bus_message_type_to_string(c->value_u8));
+                        using_bloom = true;
+                        break;
 
-                        case BUS_MATCH_MEMBER:
-                                bloom_add_pair(bloom, "member", c->value_str);
-                                using_bloom = true;
-                                break;
+                case BUS_MATCH_INTERFACE:
+                        if (!streq(c->value_str, "org.freedesktop.DBus"))
+                                matches_name_change = false;
 
-                        case BUS_MATCH_PATH:
-                                bloom_add_pair(bloom, "path", c->value_str);
-                                using_bloom = true;
-                                break;
+                        bloom_add_pair(bloom, "interface", c->value_str);
+                        using_bloom = true;
+                        break;
 
-                        case BUS_MATCH_PATH_NAMESPACE:
-                                if (!streq(c->value_str, "/")) {
-                                        bloom_add_pair(bloom, "path-slash-prefix", c->value_str);
-                                        using_bloom = true;
-                                }
-                                break;
+                case BUS_MATCH_MEMBER:
+                        if (!streq(c->value_str, "NameOwnerChanged"))
+                                matches_name_change = false;
 
-                        case BUS_MATCH_ARG...BUS_MATCH_ARG_LAST: {
-                                char buf[sizeof("arg")-1 + 2 + 1];
+                        bloom_add_pair(bloom, "member", c->value_str);
+                        using_bloom = true;
+                        break;
 
-                                snprintf(buf, sizeof(buf), "arg%u", c->type - BUS_MATCH_ARG);
-                                bloom_add_pair(bloom, buf, c->value_str);
-                                using_bloom = true;
-                                break;
-                        }
+                case BUS_MATCH_PATH:
+                        if (!streq(c->value_str, "/org/freedesktop/DBus"))
+                                matches_name_change = false;
 
-                        case BUS_MATCH_ARG_PATH...BUS_MATCH_ARG_PATH_LAST: {
-                                char buf[sizeof("arg")-1 + 2 + sizeof("-slash-prefix")];
+                        bloom_add_pair(bloom, "path", c->value_str);
+                        using_bloom = true;
+                        break;
 
-                                snprintf(buf, sizeof(buf), "arg%u-slash-prefix", c->type - BUS_MATCH_ARG_PATH);
-                                bloom_add_pair(bloom, buf, c->value_str);
+                case BUS_MATCH_PATH_NAMESPACE:
+                        if (!streq(c->value_str, "/")) {
+                                bloom_add_pair(bloom, "path-slash-prefix", c->value_str);
                                 using_bloom = true;
-                                break;
                         }
+                        break;
 
-                        case BUS_MATCH_ARG_NAMESPACE...BUS_MATCH_ARG_NAMESPACE_LAST: {
-                                char buf[sizeof("arg")-1 + 2 + sizeof("-dot-prefix")];
+                case BUS_MATCH_ARG...BUS_MATCH_ARG_LAST: {
+                        char buf[sizeof("arg")-1 + 2 + 1];
 
-                                snprintf(buf, sizeof(buf), "arg%u-dot-prefix", c->type - BUS_MATCH_ARG_NAMESPACE);
-                                bloom_add_pair(bloom, buf, c->value_str);
-                                using_bloom = true;
-                                break;
-                        }
+                        if (c->type - BUS_MATCH_ARG < 3)
+                                name_change_arg[c->type - BUS_MATCH_ARG] = c->value_str;
 
-                        case BUS_MATCH_DESTINATION:
-                                /* The bloom filter does not include
-                                   the destination, since it is only
-                                   available for broadcast messages
-                                   which do not carry a destination
-                                   since they are undirected. */
-                                break;
-
-                        case BUS_MATCH_ROOT:
-                        case BUS_MATCH_VALUE:
-                        case BUS_MATCH_LEAF:
-                        case _BUS_MATCH_NODE_TYPE_MAX:
-                        case _BUS_MATCH_NODE_TYPE_INVALID:
-                                assert_not_reached("Invalid match type?");
-                        }
+                        snprintf(buf, sizeof(buf), "arg%u", c->type - BUS_MATCH_ARG);
+                        bloom_add_pair(bloom, buf, c->value_str);
+                        using_bloom = true;
+                        break;
                 }
 
-                if (using_bloom)
-                        sz += ALIGN8(offsetof(struct kdbus_item, data64) + BLOOM_SIZE);
+                case BUS_MATCH_ARG_PATH...BUS_MATCH_ARG_PATH_LAST: {
+                        char buf[sizeof("arg")-1 + 2 + sizeof("-slash-prefix")];
 
-                m = alloca0(sz);
-                m->size = sz;
-                m->cookie = cookie;
-                m->src_id = src_id;
-
-                item = m->items;
+                        snprintf(buf, sizeof(buf), "arg%u-slash-prefix", c->type - BUS_MATCH_ARG_PATH);
+                        bloom_add_pair(bloom, buf, c->value_str);
+                        using_bloom = true;
+                        break;
+                }
 
-                if (using_bloom) {
-                        item->size = offsetof(struct kdbus_item, data64) + BLOOM_SIZE;
-                        item->type = KDBUS_MATCH_BLOOM;
-                        memcpy(item->data64, bloom, BLOOM_SIZE);
+                case BUS_MATCH_ARG_NAMESPACE...BUS_MATCH_ARG_NAMESPACE_LAST: {
+                        char buf[sizeof("arg")-1 + 2 + sizeof("-dot-prefix")];
 
-                        item = KDBUS_PART_NEXT(item);
+                        snprintf(buf, sizeof(buf), "arg%u-dot-prefix", c->type - BUS_MATCH_ARG_NAMESPACE);
+                        bloom_add_pair(bloom, buf, c->value_str);
+                        using_bloom = true;
+                        break;
                 }
 
-                if (sender) {
-                        item->size = offsetof(struct kdbus_item, str) + sender_length + 1;
-                        item->type = KDBUS_MATCH_SRC_NAME;
-                        memcpy(item->str, sender, sender_length + 1);
+                case BUS_MATCH_DESTINATION:
+                        /* The bloom filter does not include
+                           the destination, since it is only
+                           available for broadcast messages
+                           which do not carry a destination
+                           since they are undirected. */
+                        break;
+
+                case BUS_MATCH_ROOT:
+                case BUS_MATCH_VALUE:
+                case BUS_MATCH_LEAF:
+                case _BUS_MATCH_NODE_TYPE_MAX:
+                case _BUS_MATCH_NODE_TYPE_INVALID:
+                        assert_not_reached("Invalid match type?");
                 }
+        }
 
-                r = ioctl(bus->input_fd, KDBUS_CMD_MATCH_ADD, m);
-                if (r < 0)
-                        return -errno;
+        if (using_bloom)
+                sz += ALIGN8(offsetof(struct kdbus_item, data64) + BLOOM_SIZE);
 
-        } else {
-                return sd_bus_call_method(
-                                bus,
-                                "org.freedesktop.DBus",
-                                "/",
-                                "org.freedesktop.DBus",
-                                "AddMatch",
-                                NULL,
-                                NULL,
-                                "s",
-                                match);
+        m = alloca0(sz);
+        m->size = sz;
+        m->cookie = cookie;
+        m->src_id = src_id;
+
+        item = m->items;
+
+        if (using_bloom) {
+                item->size = offsetof(struct kdbus_item, data64) + BLOOM_SIZE;
+                item->type = KDBUS_MATCH_BLOOM;
+                memcpy(item->data64, bloom, BLOOM_SIZE);
+
+                item = KDBUS_ITEM_NEXT(item);
+        }
+
+        if (sender) {
+                item->size = offsetof(struct kdbus_item, str) + sender_length + 1;
+                item->type = KDBUS_MATCH_SRC_NAME;
+                memcpy(item->str, sender, sender_length + 1);
+        }
+
+        r = ioctl(bus->input_fd, KDBUS_CMD_MATCH_ADD, m);
+        if (r < 0)
+                return -errno;
+
+        if (matches_name_change) {
+
+                /* If this match could theoretically match
+                 * NameOwnerChanged messages, we need to
+                 * install a second non-bloom filter explitly
+                 * for it */
+
+                r = add_name_change_match(bus, cookie, name_change_arg[0], name_change_arg[1], name_change_arg[2]);
+                if (r < 0)
+                        return r;
         }
 
         return 0;
 }
 
-int bus_remove_match_internal(
+static int bus_add_match_internal_dbus1(
+                sd_bus *bus,
+                const char *match) {
+
+        assert(bus);
+        assert(match);
+
+        return sd_bus_call_method(
+                        bus,
+                        "org.freedesktop.DBus",
+                        "/",
+                        "org.freedesktop.DBus",
+                        "AddMatch",
+                        NULL,
+                        NULL,
+                        "s",
+                        match);
+}
+
+int bus_add_match_internal(
+                sd_bus *bus,
+                const char *match,
+                struct bus_match_component *components,
+                unsigned n_components,
+                uint64_t cookie) {
+
+        assert(bus);
+        assert(match);
+
+        if (bus->is_kernel)
+                return bus_add_match_internal_kernel(bus, match, components, n_components, cookie);
+        else
+                return bus_add_match_internal_dbus1(bus, match);
+}
+
+static int bus_remove_match_internal_kernel(
                 sd_bus *bus,
                 const char *match,
                 uint64_t cookie) {
 
+        struct kdbus_cmd_match m;
         int r;
 
         assert(bus);
         assert(match);
 
-        if (bus->is_kernel) {
-                struct kdbus_cmd_match m;
+        zero(m);
+        m.size = offsetof(struct kdbus_cmd_match, items);
+        m.cookie = cookie;
 
-                zero(m);
-                m.size = offsetof(struct kdbus_cmd_match, items);
-                m.cookie = cookie;
+        r = ioctl(bus->input_fd, KDBUS_CMD_MATCH_REMOVE, &m);
+        if (r < 0)
+                return -errno;
 
-                r = ioctl(bus->input_fd, KDBUS_CMD_MATCH_REMOVE, &m);
-                if (r < 0)
-                        return -errno;
+        return 0;
+}
 
-        } else {
-                return sd_bus_call_method(
-                                bus,
-                                "org.freedesktop.DBus",
-                                "/",
-                                "org.freedesktop.DBus",
-                                "RemoveMatch",
-                                NULL,
-                                NULL,
-                                "s",
-                                match);
-        }
+static int bus_remove_match_internal_dbus1(
+                sd_bus *bus,
+                const char *match) {
 
-        return 0;
+        assert(bus);
+        assert(match);
+
+        return sd_bus_call_method(
+                        bus,
+                        "org.freedesktop.DBus",
+                        "/",
+                        "org.freedesktop.DBus",
+                        "RemoveMatch",
+                        NULL,
+                        NULL,
+                        "s",
+                        match);
+}
+
+int bus_remove_match_internal(
+                sd_bus *bus,
+                const char *match,
+                uint64_t cookie) {
+
+        assert(bus);
+        assert(match);
+
+        if (bus->is_kernel)
+                return bus_remove_match_internal_kernel(bus, match, cookie);
+        else
+                return bus_remove_match_internal_dbus1(bus, match);
 }
 
 _public_ int sd_bus_get_owner_machine_id(sd_bus *bus, const char *name, sd_id128_t *machine) {