src/core/dbus-service.c

/* SPDX-License-Identifier: LGPL-2.1+ */

#include <stdio_ext.h>

#include "alloc-util.h"
#include "async.h"
#include "bus-internal.h"
#include "bus-util.h"
#include "dbus-cgroup.h"
#include "dbus-execute.h"
#include "dbus-kill.h"
#include "dbus-service.h"
#include "dbus-util.h"
#include "exit-status.h"
#include "fd-util.h"
#include "fileio.h"
#include "parse-util.h"
#include "path-util.h"
#include "service.h"
#include "signal-util.h"
#include "string-util.h"
#include "strv.h"
#include "unit.h"

static BUS_DEFINE_PROPERTY_GET_ENUM(property_get_type, service_type, ServiceType);
static BUS_DEFINE_PROPERTY_GET_ENUM(property_get_result, service_result, ServiceResult);
static BUS_DEFINE_PROPERTY_GET_ENUM(property_get_restart, service_restart, ServiceRestart);
static BUS_DEFINE_PROPERTY_GET_ENUM(property_get_notify_access, notify_access, NotifyAccess);
static BUS_DEFINE_PROPERTY_GET_ENUM(property_get_emergency_action, emergency_action, EmergencyAction);

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

        ExitStatusSet *status_set = userdata;
        Iterator i;
        void *id;
        int r;

        assert(bus);
        assert(reply);
        assert(status_set);

        r = sd_bus_message_open_container(reply, 'r', "aiai");
        if (r < 0)
                return r;

        r = sd_bus_message_open_container(reply, 'a', "i");
        if (r < 0)
                return r;

        SET_FOREACH(id, status_set->status, i) {
                int val = PTR_TO_INT(id);

                if (val < 0 || val > 255)
                        continue;

                r = sd_bus_message_append_basic(reply, 'i', &val);
                if (r < 0)
                        return r;
        }

        r = sd_bus_message_close_container(reply);
        if (r < 0)
                return r;

        r = sd_bus_message_open_container(reply, 'a', "i");
        if (r < 0)
                return r;

        SET_FOREACH(id, status_set->signal, i) {
                int val = PTR_TO_INT(id);
                const char *str;

                str = signal_to_string(val);
                if (!str)
                        continue;

                r = sd_bus_message_append_basic(reply, 'i', &val);
                if (r < 0)
                        return r;
        }

        r = sd_bus_message_close_container(reply);
        if (r < 0)
                return r;

        return sd_bus_message_close_container(reply);
}

const sd_bus_vtable bus_service_vtable[] = {
        SD_BUS_VTABLE_START(0),
        SD_BUS_PROPERTY("Type", "s", property_get_type, offsetof(Service, type), SD_BUS_VTABLE_PROPERTY_CONST),
        SD_BUS_PROPERTY("Restart", "s", property_get_restart, offsetof(Service, restart), SD_BUS_VTABLE_PROPERTY_CONST),
        SD_BUS_PROPERTY("PIDFile", "s", NULL, offsetof(Service, pid_file), SD_BUS_VTABLE_PROPERTY_CONST),
        SD_BUS_PROPERTY("NotifyAccess", "s", property_get_notify_access, offsetof(Service, notify_access), SD_BUS_VTABLE_PROPERTY_CONST),
        SD_BUS_PROPERTY("RestartUSec", "t", bus_property_get_usec, offsetof(Service, restart_usec), SD_BUS_VTABLE_PROPERTY_CONST),
        SD_BUS_PROPERTY("TimeoutStartUSec", "t", bus_property_get_usec, offsetof(Service, timeout_start_usec), SD_BUS_VTABLE_PROPERTY_CONST),
        SD_BUS_PROPERTY("TimeoutStopUSec", "t", bus_property_get_usec, offsetof(Service, timeout_stop_usec), SD_BUS_VTABLE_PROPERTY_CONST),
        SD_BUS_PROPERTY("RuntimeMaxUSec", "t", bus_property_get_usec, offsetof(Service, runtime_max_usec), SD_BUS_VTABLE_PROPERTY_CONST),
        SD_BUS_PROPERTY("WatchdogUSec", "t", bus_property_get_usec, offsetof(Service, watchdog_usec), SD_BUS_VTABLE_PROPERTY_CONST),
        BUS_PROPERTY_DUAL_TIMESTAMP("WatchdogTimestamp", offsetof(Service, watchdog_timestamp), 0),
        SD_BUS_PROPERTY("PermissionsStartOnly", "b", bus_property_get_bool, offsetof(Service, permissions_start_only), SD_BUS_VTABLE_PROPERTY_CONST|SD_BUS_VTABLE_HIDDEN), /* 😷 deprecated */
        SD_BUS_PROPERTY("RootDirectoryStartOnly", "b", bus_property_get_bool, offsetof(Service, root_directory_start_only), SD_BUS_VTABLE_PROPERTY_CONST),
        SD_BUS_PROPERTY("RemainAfterExit", "b", bus_property_get_bool, offsetof(Service, remain_after_exit), SD_BUS_VTABLE_PROPERTY_CONST),
        SD_BUS_PROPERTY("GuessMainPID", "b", bus_property_get_bool, offsetof(Service, guess_main_pid), SD_BUS_VTABLE_PROPERTY_CONST),
        SD_BUS_PROPERTY("RestartPreventExitStatus", "(aiai)", property_get_exit_status_set, offsetof(Service, restart_prevent_status), SD_BUS_VTABLE_PROPERTY_CONST),
        SD_BUS_PROPERTY("RestartForceExitStatus", "(aiai)", property_get_exit_status_set, offsetof(Service, restart_force_status), SD_BUS_VTABLE_PROPERTY_CONST),
        SD_BUS_PROPERTY("SuccessExitStatus", "(aiai)", property_get_exit_status_set, offsetof(Service, success_status), SD_BUS_VTABLE_PROPERTY_CONST),
        SD_BUS_PROPERTY("MainPID", "u", bus_property_get_pid, offsetof(Service, main_pid), SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
        SD_BUS_PROPERTY("ControlPID", "u", bus_property_get_pid, offsetof(Service, control_pid), SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
        SD_BUS_PROPERTY("BusName", "s", NULL, offsetof(Service, bus_name), SD_BUS_VTABLE_PROPERTY_CONST),
        SD_BUS_PROPERTY("FileDescriptorStoreMax", "u", bus_property_get_unsigned, offsetof(Service, n_fd_store_max), SD_BUS_VTABLE_PROPERTY_CONST),
        SD_BUS_PROPERTY("NFileDescriptorStore", "u", bus_property_get_unsigned, offsetof(Service, n_fd_store), 0),
        SD_BUS_PROPERTY("StatusText", "s", NULL, offsetof(Service, status_text), SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
        SD_BUS_PROPERTY("StatusErrno", "i", bus_property_get_int, offsetof(Service, status_errno), SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
        SD_BUS_PROPERTY("Result", "s", property_get_result, offsetof(Service, result), SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
        SD_BUS_PROPERTY("USBFunctionDescriptors", "s", NULL, offsetof(Service, usb_function_descriptors), SD_BUS_VTABLE_PROPERTY_CONST),
        SD_BUS_PROPERTY("USBFunctionStrings", "s", NULL, offsetof(Service, usb_function_strings), SD_BUS_VTABLE_PROPERTY_CONST),
        SD_BUS_PROPERTY("UID", "u", bus_property_get_uid, offsetof(Unit, ref_uid), SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
        SD_BUS_PROPERTY("GID", "u", bus_property_get_gid, offsetof(Unit, ref_gid), SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
        SD_BUS_PROPERTY("NRestarts", "u", bus_property_get_unsigned, offsetof(Service, n_restarts), SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),

        BUS_EXEC_STATUS_VTABLE("ExecMain", offsetof(Service, main_exec_status), SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
        BUS_EXEC_COMMAND_LIST_VTABLE("ExecStartPre", offsetof(Service, exec_command[SERVICE_EXEC_START_PRE]), SD_BUS_VTABLE_PROPERTY_EMITS_INVALIDATION),
        BUS_EXEC_COMMAND_LIST_VTABLE("ExecStart", offsetof(Service, exec_command[SERVICE_EXEC_START]), SD_BUS_VTABLE_PROPERTY_EMITS_INVALIDATION),
        BUS_EXEC_COMMAND_LIST_VTABLE("ExecStartPost", offsetof(Service, exec_command[SERVICE_EXEC_START_POST]), SD_BUS_VTABLE_PROPERTY_EMITS_INVALIDATION),
        BUS_EXEC_COMMAND_LIST_VTABLE("ExecReload", offsetof(Service, exec_command[SERVICE_EXEC_RELOAD]), SD_BUS_VTABLE_PROPERTY_EMITS_INVALIDATION),
        BUS_EXEC_COMMAND_LIST_VTABLE("ExecStop", offsetof(Service, exec_command[SERVICE_EXEC_STOP]), SD_BUS_VTABLE_PROPERTY_EMITS_INVALIDATION),
        BUS_EXEC_COMMAND_LIST_VTABLE("ExecStopPost", offsetof(Service, exec_command[SERVICE_EXEC_STOP_POST]), SD_BUS_VTABLE_PROPERTY_EMITS_INVALIDATION),

        /* The following four are obsolete, and thus marked hidden here. They moved into the Unit interface */
        SD_BUS_PROPERTY("StartLimitInterval", "t", bus_property_get_usec, offsetof(Unit, start_limit.interval), SD_BUS_VTABLE_PROPERTY_CONST|SD_BUS_VTABLE_HIDDEN),
        SD_BUS_PROPERTY("StartLimitBurst", "u", bus_property_get_unsigned, offsetof(Unit, start_limit.burst), SD_BUS_VTABLE_PROPERTY_CONST|SD_BUS_VTABLE_HIDDEN),
        SD_BUS_PROPERTY("StartLimitAction", "s", property_get_emergency_action, offsetof(Unit, start_limit_action), SD_BUS_VTABLE_PROPERTY_CONST|SD_BUS_VTABLE_HIDDEN),
        SD_BUS_PROPERTY("FailureAction", "s", property_get_emergency_action, offsetof(Unit, failure_action), SD_BUS_VTABLE_PROPERTY_CONST|SD_BUS_VTABLE_HIDDEN),
        SD_BUS_PROPERTY("RebootArgument", "s", NULL, offsetof(Unit, reboot_arg), SD_BUS_VTABLE_PROPERTY_CONST|SD_BUS_VTABLE_HIDDEN),
        SD_BUS_VTABLE_END
};

static int bus_set_transient_exit_status(
                Unit *u,
                const char *name,
                ExitStatusSet *status_set,
                sd_bus_message *message,
                UnitWriteFlags flags,
                sd_bus_error *error) {

        const int *status, *signal;
        size_t sz_status, sz_signal, i;
        int r;

        r = sd_bus_message_enter_container(message, 'r', "aiai");
        if (r < 0)
                return r;

        r = sd_bus_message_read_array(message, 'i', (const void **) &status, &sz_status);
        if (r < 0)
                return r;

        r = sd_bus_message_read_array(message, 'i', (const void **) &signal, &sz_signal);
        if (r < 0)
                return r;

        r = sd_bus_message_exit_container(message);
        if (r < 0)
                return r;

        if (sz_status == 0 && sz_signal == 0 && !UNIT_WRITE_FLAGS_NOOP(flags)) {
                exit_status_set_free(status_set);
                unit_write_settingf(u, flags, name, "%s=", name);
                return 1;
        }

        for (i = 0; i < sz_status; i++) {
                if (status[i] < 0 || status[i] > 255)
                        return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid status code in %s: %i", name, status[i]);

                if (!UNIT_WRITE_FLAGS_NOOP(flags)) {
                        r = set_ensure_allocated(&status_set->status, NULL);
                        if (r < 0)
                                return r;

                        r = set_put(status_set->status, INT_TO_PTR(status[i]));
                        if (r < 0)
                                return r;

                        unit_write_settingf(u, flags, name, "%s=%i", name, status[i]);
                }
        }

        for (i = 0; i < sz_signal; i++) {
                const char *str;

                str = signal_to_string(signal[i]);
                if (!str)
                        return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid signal in %s: %i", name, signal[i]);

                if (!UNIT_WRITE_FLAGS_NOOP(flags)) {
                        r = set_ensure_allocated(&status_set->signal, NULL);
                        if (r < 0)
                                return r;

                        r = set_put(status_set->signal, INT_TO_PTR(signal[i]));
                        if (r < 0)
                                return r;

                        unit_write_settingf(u, flags, name, "%s=%s", name, str);
                }
        }

        return 1;
}

static int bus_set_transient_std_fd(
                Unit *u,
                const char *name,
                int *p,
                bool *b,
                sd_bus_message *message,
                UnitWriteFlags flags,
                sd_bus_error *error) {

        int fd, r;

        assert(p);
        assert(b);

        r = sd_bus_message_read(message, "h", &fd);
        if (r < 0)
                return r;

        if (!UNIT_WRITE_FLAGS_NOOP(flags)) {
                int copy;

                copy = fcntl(fd, F_DUPFD_CLOEXEC, 3);
                if (copy < 0)
                        return -errno;

                asynchronous_close(*p);
                *p = copy;
                *b = true;
        }

        return 1;
}
static BUS_DEFINE_SET_TRANSIENT_PARSE(notify_access, NotifyAccess, notify_access_from_string);
static BUS_DEFINE_SET_TRANSIENT_PARSE(service_type, ServiceType, service_type_from_string);
static BUS_DEFINE_SET_TRANSIENT_PARSE(service_restart, ServiceRestart, service_restart_from_string);
static BUS_DEFINE_SET_TRANSIENT_STRING_WITH_CHECK(bus_name, service_name_is_valid);

static int bus_service_set_transient_property(
                Service *s,
                const char *name,
                sd_bus_message *message,
                UnitWriteFlags flags,
                sd_bus_error *error) {

        Unit *u = UNIT(s);
        ServiceExecCommand ci;
        int r;

        assert(s);
        assert(name);
        assert(message);

        flags |= UNIT_PRIVATE;

        if (streq(name, "PermissionsStartOnly"))
                return bus_set_transient_bool(u, name, &s->permissions_start_only, message, flags, error);

        if (streq(name, "RootDirectoryStartOnly"))
                return bus_set_transient_bool(u, name, &s->root_directory_start_only, message, flags, error);

        if (streq(name, "RemainAfterExit"))
                return bus_set_transient_bool(u, name, &s->remain_after_exit, message, flags, error);

        if (streq(name, "GuessMainPID"))
                return bus_set_transient_bool(u, name, &s->guess_main_pid, message, flags, error);

        if (streq(name, "Type"))
                return bus_set_transient_service_type(u, name, &s->type, message, flags, error);

        if (streq(name, "RestartUSec"))
                return bus_set_transient_usec(u, name, &s->restart_usec, message, flags, error);

        if (streq(name, "TimeoutStartUSec")) {
                r = bus_set_transient_usec(u, name, &s->timeout_start_usec, message, flags, error);
                if (r >= 0 && !UNIT_WRITE_FLAGS_NOOP(flags))
                        s->start_timeout_defined = true;

                return r;
        }

        if (streq(name, "TimeoutStopUSec"))
                return bus_set_transient_usec(u, name, &s->timeout_stop_usec, message, flags, error);

        if (streq(name, "RuntimeMaxUSec"))
                return bus_set_transient_usec(u, name, &s->runtime_max_usec, message, flags, error);

        if (streq(name, "WatchdogUSec"))
                return bus_set_transient_usec(u, name, &s->watchdog_usec, message, flags, error);

        if (streq(name, "FileDescriptorStoreMax"))
                return bus_set_transient_unsigned(u, name, &s->n_fd_store_max, message, flags, error);

        if (streq(name, "NotifyAccess"))
                return bus_set_transient_notify_access(u, name, &s->notify_access, message, flags, error);

        if (streq(name, "PIDFile")) {
                _cleanup_free_ char *n = NULL;
                const char *v, *e;

                r = sd_bus_message_read(message, "s", &v);
                if (r < 0)
                        return r;

                n = path_make_absolute(v, u->manager->prefix[EXEC_DIRECTORY_RUNTIME]);
                if (!n)
                        return -ENOMEM;

                path_simplify(n, true);

                if (!path_is_normalized(n))
                        return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "PIDFile= path '%s' is not valid", n);

                e = path_startswith(n, "/var/run/");
                if (e) {
                        char *z;

                        z = strjoin("/run/", e);
                        if (!z)
                                return log_oom();

                        if (!UNIT_WRITE_FLAGS_NOOP(flags))
                                log_unit_notice(u, "Transient unit's PIDFile= property references path below legacy directory /var/run, updating %s → %s; please update client accordingly.", n, z);

                        free_and_replace(s->pid_file, z);
                } else
                        free_and_replace(s->pid_file, n);

                return 1;
        }

        if (streq(name, "USBFunctionDescriptors"))
                return bus_set_transient_path(u, name, &s->usb_function_descriptors, message, flags, error);

        if (streq(name, "USBFunctionStrings"))
                return bus_set_transient_path(u, name, &s->usb_function_strings, message, flags, error);

        if (streq(name, "BusName"))
                return bus_set_transient_bus_name(u, name, &s->bus_name, message, flags, error);

        if (streq(name, "Restart"))
                return bus_set_transient_service_restart(u, name, &s->restart, message, flags, error);

        if (streq(name, "RestartPreventExitStatus"))
                return bus_set_transient_exit_status(u, name, &s->restart_prevent_status, message, flags, error);

        if (streq(name, "RestartForceExitStatus"))
                return bus_set_transient_exit_status(u, name, &s->restart_force_status, message, flags, error);

        if (streq(name, "SuccessExitStatus"))
                return bus_set_transient_exit_status(u, name, &s->success_status, message, flags, error);

        ci = service_exec_command_from_string(name);
        if (ci >= 0)
                return bus_set_transient_exec_command(u, name, &s->exec_command[ci], message, flags, error);

        if (streq(name, "StandardInputFileDescriptor"))
                return bus_set_transient_std_fd(u, name, &s->stdin_fd, &s->exec_context.stdio_as_fds, message, flags, error);

        if (streq(name, "StandardOutputFileDescriptor"))
                return bus_set_transient_std_fd(u, name, &s->stdout_fd, &s->exec_context.stdio_as_fds, message, flags, error);

        if (streq(name, "StandardErrorFileDescriptor"))
                return bus_set_transient_std_fd(u, name, &s->stderr_fd, &s->exec_context.stdio_as_fds, message, flags, error);

        return 0;
}

int bus_service_set_property(
                Unit *u,
                const char *name,
                sd_bus_message *message,
                UnitWriteFlags flags,
                sd_bus_error *error) {

        Service *s = SERVICE(u);
        int r;

        assert(s);
        assert(name);
        assert(message);

        r = bus_cgroup_set_property(u, &s->cgroup_context, name, message, flags, error);
        if (r != 0)
                return r;

        if (u->transient && u->load_state == UNIT_STUB) {
                /* This is a transient unit, let's load a little more */

                r = bus_service_set_transient_property(s, name, message, flags, error);
                if (r != 0)
                        return r;

                r = bus_exec_context_set_transient_property(u, &s->exec_context, name, message, flags, error);
                if (r != 0)
                        return r;

                r = bus_kill_context_set_transient_property(u, &s->kill_context, name, message, flags, error);
                if (r != 0)
                        return r;
        }

        return 0;
}

int bus_service_commit_properties(Unit *u) {
        assert(u);

        unit_invalidate_cgroup_members_masks(u);
        unit_realize_cgroup(u);

        return 0;
}