dbus.c revision bbc2908635ca3ded9162504683fa126809f0ec14
/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/***
This file is part of systemd.
Copyright 2010 Lennart Poettering
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <errno.h>
#include <unistd.h>
#include "sd-bus.h"
#include "log.h"
#include "strv.h"
#include "mkdir.h"
#include "missing.h"
#include "dbus-unit.h"
#include "dbus-job.h"
#include "dbus-manager.h"
#include "dbus-execute.h"
#include "dbus-kill.h"
#include "dbus-cgroup.h"
#include "special.h"
#include "dbus.h"
#include "bus-util.h"
#include "bus-error.h"
#include "bus-common-errors.h"
#include "strxcpyx.h"
#include "bus-internal.h"
#include "selinux-access.h"
#define CONNECTIONS_MAX 4096
int bus_send_queued_message(Manager *m) {
int r;
assert(m);
if (!m->queued_message)
return 0;
/* If we cannot get rid of this message we won't dispatch any
* D-Bus messages, so that we won't end up wanting to queue
* another message. */
if (r < 0)
log_warning_errno(r, "Failed to send queued message: %m");
return 0;
}
int r;
assert(m);
if (!sd_bus_is_server(bus)) {
if (r < 0)
return r;
return 0;
}
/* only accept org.freedesktop.systemd1.Agent from UID=0 */
if (r < 0)
return r;
if (r < 0 || sender_uid != 0)
return 0;
/* parse 'cgroup-empty' notification */
if (r < 0) {
return 0;
}
/* if running as system-instance, forward under our name */
if (r >= 0)
if (r < 0)
log_warning_errno(r, "Failed to forward Released message: %m");
}
return 0;
}
assert(m);
destroy_bus(m, &m->api_bus);
if (bus == m->system_bus)
destroy_bus(m, &m->system_bus);
log_debug("Got disconnect on private connection.");
destroy_bus(m, &bus);
}
return 0;
}
static int signal_activation_request(sd_bus_message *message, void *userdata, sd_bus_error *ret_error) {
const char *name;
Unit *u;
int r;
assert(m);
if (r < 0) {
return 0;
}
r = sd_bus_error_setf(&error, BUS_ERROR_SHUTTING_DOWN, "Refusing activation, D-Bus is shutting down.");
goto failed;
}
if (r < 0)
goto failed;
if (u->refuse_manual_start) {
r = sd_bus_error_setf(&error, BUS_ERROR_ONLY_BY_DEPENDENCY, "Operation refused, %s may be requested by dependency only.", u->id);
goto failed;
}
if (r < 0)
goto failed;
/* Successfully queued, that's it for us */
return 0;
if (!sd_bus_error_is_set(&error))
sd_bus_error_set_errno(&error, r);
r = sd_bus_message_new_signal(sd_bus_message_get_bus(message), &reply, "/org/freedesktop/systemd1", "org.freedesktop.systemd1.Activator", "ActivationFailure");
if (r < 0) {
return 0;
}
if (r < 0) {
return 0;
}
if (r < 0)
return log_error_errno(r, "Failed to respond with to bus activation request: %m");
return 0;
}
#ifdef HAVE_SELINUX
Job *j;
int r;
/* Our own method calls are all protected individually with
* selinux checks, but the built-in interfaces need to be
* protected too. */
verb = "reload";
verb = "status";
else
return 0;
if (r < 0)
return r;
return 0;
}
if (r < 0)
return 0;
if (r < 0)
return 0;
u = manager_get_unit_by_pid(m, pid);
} else {
r = manager_get_job_from_dbus_path(m, path, &j);
if (r >= 0)
u = j->unit;
else
}
if (!u)
return 0;
if (r < 0)
return r;
return 0;
}
#endif
static int bus_job_find(sd_bus *bus, const char *path, const char *interface, void *userdata, void **found, sd_bus_error *error) {
Job *j;
int r;
assert(m);
r = manager_get_job_from_dbus_path(m, path, &j);
if (r < 0)
return 0;
*found = j;
return 1;
}
Unit *u;
int r;
assert(m);
if (!message)
return 0;
if (r < 0)
return r;
if (r < 0)
return r;
u = manager_get_unit_by_pid(m, pid);
} else {
if (r < 0)
return 0;
}
if (!u)
return 0;
*unit = u;
return 1;
}
static int bus_unit_find(sd_bus *bus, const char *path, const char *interface, void *userdata, void **found, sd_bus_error *error) {
assert(m);
}
static int bus_unit_interface_find(sd_bus *bus, const char *path, const char *interface, void *userdata, void **found, sd_bus_error *error) {
Unit *u;
int r;
assert(m);
if (r <= 0)
return r;
return 0;
*found = u;
return 1;
}
static int bus_unit_cgroup_find(sd_bus *bus, const char *path, const char *interface, void *userdata, void **found, sd_bus_error *error) {
Unit *u;
int r;
assert(m);
if (r <= 0)
return r;
return 0;
if (!unit_get_cgroup_context(u))
return 0;
*found = u;
return 1;
}
static int bus_cgroup_context_find(sd_bus *bus, const char *path, const char *interface, void *userdata, void **found, sd_bus_error *error) {
CGroupContext *c;
Unit *u;
int r;
assert(m);
if (r <= 0)
return r;
return 0;
c = unit_get_cgroup_context(u);
if (!c)
return 0;
*found = c;
return 1;
}
static int bus_exec_context_find(sd_bus *bus, const char *path, const char *interface, void *userdata, void **found, sd_bus_error *error) {
ExecContext *c;
Unit *u;
int r;
assert(m);
if (r <= 0)
return r;
return 0;
c = unit_get_exec_context(u);
if (!c)
return 0;
*found = c;
return 1;
}
static int bus_kill_context_find(sd_bus *bus, const char *path, const char *interface, void *userdata, void **found, sd_bus_error *error) {
KillContext *c;
Unit *u;
int r;
assert(m);
if (r <= 0)
return r;
return 0;
c = unit_get_kill_context(u);
if (!c)
return 0;
*found = c;
return 1;
}
static int bus_job_enumerate(sd_bus *bus, const char *path, void *userdata, char ***nodes, sd_bus_error *error) {
_cleanup_free_ char **l = NULL;
unsigned k = 0;
Iterator i;
Job *j;
if (!l)
return -ENOMEM;
HASHMAP_FOREACH(j, m->jobs, i) {
l[k] = job_dbus_path(j);
if (!l[k])
return -ENOMEM;
k++;
}
*nodes = l;
l = NULL;
return k;
}
static int bus_unit_enumerate(sd_bus *bus, const char *path, void *userdata, char ***nodes, sd_bus_error *error) {
_cleanup_free_ char **l = NULL;
unsigned k = 0;
Iterator i;
Unit *u;
if (!l)
return -ENOMEM;
HASHMAP_FOREACH(u, m->units, i) {
l[k] = unit_dbus_path(u);
if (!l[k])
return -ENOMEM;
k++;
}
*nodes = l;
l = NULL;
return k;
}
UnitType t;
int r;
assert(m);
#ifdef HAVE_SELINUX
if (r < 0)
return log_error_errno(r, "Failed to add SELinux access filter: %m");
#endif
r = sd_bus_add_object_vtable(bus, NULL, "/org/freedesktop/systemd1", "org.freedesktop.systemd1.Manager", bus_manager_vtable, m);
if (r < 0)
return log_error_errno(r, "Failed to register Manager vtable: %m");
r = sd_bus_add_fallback_vtable(bus, NULL, "/org/freedesktop/systemd1/job", "org.freedesktop.systemd1.Job", bus_job_vtable, bus_job_find, m);
if (r < 0)
return log_error_errno(r, "Failed to register Job vtable: %m");
if (r < 0)
return log_error_errno(r, "Failed to add job enumerator: %m");
r = sd_bus_add_fallback_vtable(bus, NULL, "/org/freedesktop/systemd1/unit", "org.freedesktop.systemd1.Unit", bus_unit_vtable, bus_unit_find, m);
if (r < 0)
return log_error_errno(r, "Failed to register Unit vtable: %m");
if (r < 0)
return log_error_errno(r, "Failed to add job enumerator: %m");
for (t = 0; t < _UNIT_TYPE_MAX; t++) {
r = sd_bus_add_fallback_vtable(bus, NULL, "/org/freedesktop/systemd1/unit", unit_vtable[t]->bus_interface, unit_vtable[t]->bus_vtable, bus_unit_interface_find, m);
if (r < 0)
return log_error_errno(r, "Failed to register type specific vtable for %s: %m", unit_vtable[t]->bus_interface);
if (unit_vtable[t]->cgroup_context_offset > 0) {
r = sd_bus_add_fallback_vtable(bus, NULL, "/org/freedesktop/systemd1/unit", unit_vtable[t]->bus_interface, bus_unit_cgroup_vtable, bus_unit_cgroup_find, m);
if (r < 0)
return log_error_errno(r, "Failed to register control group unit vtable for %s: %m", unit_vtable[t]->bus_interface);
r = sd_bus_add_fallback_vtable(bus, NULL, "/org/freedesktop/systemd1/unit", unit_vtable[t]->bus_interface, bus_cgroup_vtable, bus_cgroup_context_find, m);
if (r < 0)
return log_error_errno(r, "Failed to register control group vtable for %s: %m", unit_vtable[t]->bus_interface);
}
if (unit_vtable[t]->exec_context_offset > 0) {
r = sd_bus_add_fallback_vtable(bus, NULL, "/org/freedesktop/systemd1/unit", unit_vtable[t]->bus_interface, bus_exec_vtable, bus_exec_context_find, m);
if (r < 0)
return log_error_errno(r, "Failed to register execute vtable for %s: %m", unit_vtable[t]->bus_interface);
}
if (unit_vtable[t]->kill_context_offset > 0) {
r = sd_bus_add_fallback_vtable(bus, NULL, "/org/freedesktop/systemd1/unit", unit_vtable[t]->bus_interface, bus_kill_vtable, bus_kill_context_find, m);
if (r < 0)
return log_error_errno(r, "Failed to register kill vtable for %s: %m", unit_vtable[t]->bus_interface);
}
}
return 0;
}
int r;
assert(m);
r = sd_bus_add_match(
bus,
NULL,
"sender='org.freedesktop.DBus.Local',"
"type='signal',"
"path='/org/freedesktop/DBus/Local',"
"interface='org.freedesktop.DBus.Local',"
"member='Disconnected'",
signal_disconnected, m);
if (r < 0)
return log_error_errno(r, "Failed to register match for Disconnected message: %m");
return 0;
}
int r;
assert(s);
assert(m);
if (nfd < 0) {
return 0;
}
log_warning("Too many concurrent connections, refusing");
return 0;
}
if (r < 0) {
log_oom();
return 0;
}
r = sd_bus_new(&bus);
if (r < 0) {
log_warning_errno(r, "Failed to allocate new private connection bus: %m");
return 0;
}
if (r < 0) {
log_warning_errno(r, "Failed to set fd on new connection bus: %m");
return 0;
}
nfd = -1;
r = bus_check_peercred(bus);
if (r < 0) {
log_warning_errno(r, "Incoming private connection from unprivileged client, refusing: %m");
return 0;
}
if (r < 0) {
log_warning_errno(r, "Failed to enable server support for new connection bus: %m");
return 0;
}
if (r < 0) {
log_warning_errno(r, "Failed to enable credentials for new connection: %m");
return 0;
}
r = sd_bus_start(bus);
if (r < 0) {
log_warning_errno(r, "Failed to start new connection bus: %m");
return 0;
}
if (r < 0) {
log_warning_errno(r, "Failed to attach new connection bus to event loop: %m");
return 0;
}
if (m->running_as == MANAGER_SYSTEM) {
/* When we run as system instance we get the Released
* signal via a direct connection */
r = sd_bus_add_match(
bus,
NULL,
"type='signal',"
"interface='org.freedesktop.systemd1.Agent',"
"member='Released',"
"path='/org/freedesktop/systemd1/agent'",
if (r < 0) {
log_warning_errno(r, "Failed to register Released match on new connection bus: %m");
return 0;
}
}
r = bus_setup_disconnected_match(m, bus);
if (r < 0)
return 0;
r = bus_setup_api_vtables(m, bus);
if (r < 0) {
log_warning_errno(r, "Failed to set up API vtables on new connection bus: %m");
return 0;
}
if (r < 0) {
log_warning_errno(r, "Failed to add new connection bus to set: %m");
return 0;
}
log_debug("Accepted new private connection.");
return 0;
}
char **i;
int r;
assert(m);
if (r < 0)
return log_error_errno(r, "Failed to get initial list of names: %m");
/* This is a bit hacky, we say the owner of the name is the
* name itself, because we don't want the extra traffic to
* figure out the real owner. */
STRV_FOREACH(i, names) {
Unit *u;
u = hashmap_get(m->watch_bus, *i);
if (u)
}
return 0;
}
Iterator i;
char *name;
Unit *u;
int r;
assert(m);
/* Let's make sure we have enough credential bits so that we can make security and selinux decisions */
if (r < 0)
log_warning_errno(r, "Failed to enable credential passing, ignoring: %m");
r = bus_setup_api_vtables(m, bus);
if (r < 0)
return r;
if (r < 0)
log_error_errno(r, "Failed to subscribe to NameOwnerChanged signal: %m");
}
r = sd_bus_add_match(
bus,
NULL,
"type='signal',"
"sender='org.freedesktop.DBus',"
"path='/org/freedesktop/DBus',"
"interface='org.freedesktop.systemd1.Activator',"
"member='ActivationRequest'",
if (r < 0)
log_warning_errno(r, "Failed to subscribe to activation signal: %m");
/* Allow replacing of our name, to ease implementation of
* reexecution, where we keep the old connection open until
* after the new connection is set up and the name installed
* to allow clients to synchronously wait for reexecution to
* finish */
r = sd_bus_request_name(bus,"org.freedesktop.systemd1", SD_BUS_NAME_REPLACE_EXISTING|SD_BUS_NAME_ALLOW_REPLACEMENT);
if (r < 0)
return log_error_errno(r, "Failed to register name: %m");
bus_list_names(m, bus);
log_debug("Successfully connected to API bus.");
return 0;
}
static int bus_init_api(Manager *m) {
int r;
if (m->api_bus)
return 0;
/* The API and system bus is the same if we are running in system mode */
else {
if (m->running_as == MANAGER_SYSTEM)
r = sd_bus_open_system(&bus);
else
r = sd_bus_open_user(&bus);
if (r < 0) {
log_debug("Failed to connect to API bus, retrying later...");
return 0;
}
if (r < 0) {
log_error_errno(r, "Failed to attach API bus to event loop: %m");
return 0;
}
r = bus_setup_disconnected_match(m, bus);
if (r < 0)
return 0;
}
r = bus_setup_api(m, bus);
if (r < 0) {
log_error_errno(r, "Failed to set up API bus: %m");
return 0;
}
return 0;
}
int r;
assert(m);
/* On kdbus or if we are a user instance we get the Released message via the system bus */
r = sd_bus_add_match(
bus,
NULL,
"type='signal',"
"interface='org.freedesktop.systemd1.Agent',"
"member='Released',"
"path='/org/freedesktop/systemd1/agent'",
if (r < 0)
log_warning_errno(r, "Failed to register Released match on system bus: %m");
}
log_debug("Successfully connected to system bus.");
return 0;
}
static int bus_init_system(Manager *m) {
int r;
if (m->system_bus)
return 0;
/* The API and system bus is the same if we are running in system mode */
return 0;
}
r = sd_bus_open_system(&bus);
if (r < 0) {
log_debug("Failed to connect to system bus, retrying later...");
return 0;
}
r = bus_setup_disconnected_match(m, bus);
if (r < 0)
return 0;
if (r < 0) {
log_error_errno(r, "Failed to attach system bus to event loop: %m");
return 0;
}
r = bus_setup_system(m, bus);
if (r < 0) {
log_error_errno(r, "Failed to set up system bus: %m");
return 0;
}
m->system_bus = bus;
return 0;
}
static int bus_init_private(Manager *m) {
union sockaddr_union sa = {
};
sd_event_source *s;
int r;
assert(m);
if (m->private_listen_fd >= 0)
return 0;
/* We don't need the private socket if we have kdbus */
if (m->kdbus_fd >= 0)
return 0;
if (m->running_as == MANAGER_SYSTEM) {
/* We want the private bus only when running as init */
if (getpid() != 1)
return 0;
} else {
const char *e;
e = secure_getenv("XDG_RUNTIME_DIR");
if (!e) {
log_error("Failed to determine XDG_RUNTIME_DIR");
return -EHOSTDOWN;
}
}
if (fd < 0)
if (r < 0)
if (r < 0)
if (r < 0)
return log_error_errno(r, "Failed to allocate event source: %m");
(void) sd_event_source_set_description(s, "bus-connection");
m->private_listen_fd = fd;
m->private_listen_event_source = s;
fd = -1;
log_debug("Successfully created private D-Bus server.");
return 0;
}
int r;
if (try_bus_connect) {
r = bus_init_system(m);
if (r < 0)
return r;
r = bus_init_api(m);
if (r < 0)
return r;
}
r = bus_init_private(m);
if (r < 0)
return r;
return 0;
}
Iterator i;
Job *j;
assert(m);
if (!*bus)
return;
/* Get rid of tracked clients on this bus */
HASHMAP_FOREACH(j, m->jobs, i)
/* Get rid of queued message on this bus */
/* Possibly flush unwritten data, but only if we are
* unprivileged, since we don't want to sync here */
if (m->running_as != MANAGER_SYSTEM)
sd_bus_flush(*bus);
/* And destroy the object */
sd_bus_close(*bus);
}
sd_bus *b;
assert(m);
if (m->api_bus)
destroy_bus(m, &m->api_bus);
if (m->system_bus)
destroy_bus(m, &m->system_bus);
while ((b = set_steal_first(m->private_buses)))
destroy_bus(m, &b);
set_free(m->private_buses);
m->private_buses = NULL;
m->deserialized_subscribed = NULL;
if (m->private_listen_event_source)
}
Iterator i;
sd_bus *b;
int fd;
assert(m);
/* When we are about to reexecute we add all D-Bus fds to the
* set to pass over to the newly executed systemd. They won't
* be used there however, except thatt they are closed at the
* very end of deserialization, those making it possible for
* clients to synchronously wait for systemd to reexec by
* simply waiting for disconnection */
if (m->api_bus) {
if (fd >= 0) {
if (fd < 0)
return fd;
}
}
SET_FOREACH(b, m->private_buses, i) {
fd = sd_bus_get_fd(b);
if (fd >= 0) {
if (fd < 0)
return fd;
}
}
/* We don't offer any APIs on the system bus (well, unless it
* is the same as the API bus) hence we don't bother with it
* here */
return 0;
}
int bus_foreach_bus(
Manager *m,
void *userdata) {
Iterator i;
sd_bus *b;
int r, ret = 0;
/* Send to all direct buses, unconditionally */
SET_FOREACH(b, m->private_buses, i) {
r = send_message(b, userdata);
if (r < 0)
ret = r;
}
/* Send to API bus, but only if somebody is subscribed */
if (sd_bus_track_count(m->subscribed) > 0 ||
sd_bus_track_count(subscribed2) > 0) {
if (r < 0)
ret = r;
}
return ret;
}
const char *n;
assert(f);
for (n = sd_bus_track_first(t); n; n = sd_bus_track_next(t))
fprintf(f, "subscribed=%s\n", n);
}
int bus_track_deserialize_item(char ***l, const char *line) {
const char *e;
int r;
assert(l);
if (!e)
return 0;
r = strv_extend(l, e);
if (r < 0)
return r;
return 1;
}
int r = 0;
assert(m);
assert(t);
assert(l);
if (!strv_isempty(*l) && m->api_bus) {
char **i;
if (!*t) {
if (r < 0)
return r;
}
r = 0;
STRV_FOREACH(i, *l) {
int k;
k = sd_bus_track_add_name(*t, *i);
if (k < 0)
r = k;
}
}
strv_free(*l);
*l = NULL;
return r;
}
return bus_verify_polkit_async(call, CAP_SYS_ADMIN, "org.freedesktop.systemd1.manage-units", false, UID_INVALID, &m->polkit_registry, error);
}
/* Same as bus_verify_manage_unit_async(), but checks for CAP_KILL instead of CAP_SYS_ADMIN */
return bus_verify_polkit_async(call, CAP_KILL, "org.freedesktop.systemd1.manage-units", false, UID_INVALID, &m->polkit_registry, error);
}
return bus_verify_polkit_async(call, CAP_SYS_ADMIN, "org.freedesktop.systemd1.manage-unit-files", false, UID_INVALID, &m->polkit_registry, error);
}
return bus_verify_polkit_async(call, CAP_SYS_ADMIN, "org.freedesktop.systemd1.reload-daemon", false, UID_INVALID, &m->polkit_registry, error);
}
return bus_verify_polkit_async(call, CAP_SYS_ADMIN, "org.freedesktop.systemd1.set-environment", false, UID_INVALID, &m->polkit_registry, error);
}