src/core/dbus-job.c

/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/

/***
  This file is part of systemd.

  Copyright 2010 Lennart Poettering

  systemd is free software; you can redistribute it and/or modify it
  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 "log.h"
#include "sd-bus.h"
#include "selinux-access.h"
#include "job.h"
#include "dbus-job.h"
#include "dbus.h"

static BUS_DEFINE_PROPERTY_GET_ENUM(property_get_type, job_type, JobType);
static BUS_DEFINE_PROPERTY_GET_ENUM(property_get_state, job_state, JobState);

static int verify_sys_admin_or_owner_sync(sd_bus_message *message, Job *j, sd_bus_error *error) {
        int r;

        if (sd_bus_track_contains(j->clients, sd_bus_message_get_sender(message)))
                return 0; /* One of the job owners is calling us */

        r = sd_bus_query_sender_privilege(message, CAP_SYS_ADMIN);
        if (r < 0)
                return r;
        if (r == 0)
                return sd_bus_error_setf(error, SD_BUS_ERROR_ACCESS_DENIED, "Access denied to perform action");

        /* Root has called us */
        return 0;
}

static int property_get_unit(
                sd_bus *bus,
                const char *path,
                const char *interface,
                const char *property,
                sd_bus_message *reply,
                void *userdata,
                sd_bus_error *error) {

        _cleanup_free_ char *p = NULL;
        Job *j = userdata;

        assert(bus);
        assert(reply);
        assert(j);

        p = unit_dbus_path(j->unit);
        if (!p)
                return -ENOMEM;

        return sd_bus_message_append(reply, "(so)", j->unit->id, p);
}

int bus_job_method_cancel(sd_bus *bus, sd_bus_message *message, void *userdata, sd_bus_error *error) {
        Job *j = userdata;
        int r;

        assert(bus);
        assert(message);
        assert(j);

        r = verify_sys_admin_or_owner_sync(message, j, error);
        if (r < 0)
                return r;

        r = mac_selinux_unit_access_check(j->unit, message, "stop", error);
        if (r < 0)
                return r;

        job_finish_and_invalidate(j, JOB_CANCELED, true);

        return sd_bus_reply_method_return(message, NULL);
}

const sd_bus_vtable bus_job_vtable[] = {
        SD_BUS_VTABLE_START(0),
        SD_BUS_METHOD("Cancel", NULL, NULL, bus_job_method_cancel, SD_BUS_VTABLE_UNPRIVILEGED),
        SD_BUS_PROPERTY("Id", "u", NULL, offsetof(Job, id), SD_BUS_VTABLE_PROPERTY_CONST),
        SD_BUS_PROPERTY("Unit", "(so)", property_get_unit, 0, SD_BUS_VTABLE_PROPERTY_CONST),
        SD_BUS_PROPERTY("JobType", "s", property_get_type, offsetof(Job, type), SD_BUS_VTABLE_PROPERTY_CONST),
        SD_BUS_PROPERTY("State", "s", property_get_state, offsetof(Job, state), SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
        SD_BUS_VTABLE_END
};

static int send_new_signal(sd_bus *bus, void *userdata) {
        _cleanup_bus_message_unref_ sd_bus_message *m = NULL;
        _cleanup_free_ char *p = NULL;
        Job *j = userdata;
        int r;

        assert(bus);
        assert(j);

        p = job_dbus_path(j);
        if (!p)
                return -ENOMEM;

        r = sd_bus_message_new_signal(
                        bus,
                        &m,
                        "/org/freedesktop/systemd1",
                        "org.freedesktop.systemd1.Manager",
                        "JobNew");
        if (r < 0)
                return r;

        r = sd_bus_message_append(m, "uos", j->id, p, j->unit->id);
        if (r < 0)
                return r;

        return sd_bus_send(bus, m, NULL);
}

static int send_changed_signal(sd_bus *bus, void *userdata) {
        _cleanup_free_ char *p = NULL;
        Job *j = userdata;

        assert(bus);
        assert(j);

        p = job_dbus_path(j);
        if (!p)
                return -ENOMEM;

        return sd_bus_emit_properties_changed(bus, p, "org.freedesktop.systemd1.Job", "State", NULL);
}

void bus_job_send_change_signal(Job *j) {
        int r;

        assert(j);

        if (j->in_dbus_queue) {
                LIST_REMOVE(dbus_queue, j->manager->dbus_job_queue, j);
                j->in_dbus_queue = false;
        }

        r = bus_foreach_bus(j->manager, j->clients, j->sent_dbus_new_signal ? send_changed_signal : send_new_signal, j);
        if (r < 0)
                log_debug("Failed to send job change signal for %u: %s", j->id, strerror(-r));

        j->sent_dbus_new_signal = true;
}

static int send_removed_signal(sd_bus *bus, void *userdata) {
        _cleanup_bus_message_unref_ sd_bus_message *m = NULL;
        _cleanup_free_ char *p = NULL;
        Job *j = userdata;
        int r;

        assert(bus);
        assert(j);

        p = job_dbus_path(j);
        if (!p)
                return -ENOMEM;

        r = sd_bus_message_new_signal(
                        bus,
                        &m,
                        "/org/freedesktop/systemd1",
                        "org.freedesktop.systemd1.Manager",
                        "JobRemoved");
        if (r < 0)
                return r;

        r = sd_bus_message_append(m, "uoss", j->id, p, j->unit->id, job_result_to_string(j->result));
        if (r < 0)
                return r;

        return sd_bus_send(bus, m, NULL);
}

void bus_job_send_removed_signal(Job *j) {
        int r;

        assert(j);

        if (!j->sent_dbus_new_signal)
                bus_job_send_change_signal(j);

        r = bus_foreach_bus(j->manager, j->clients, send_removed_signal, j);
        if (r < 0)
                log_debug("Failed to send job remove signal for %u: %s", j->id, strerror(-r));
}