src/core/dbus-scope.c

   1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
   2
   3 #include "alloc-util.h"
   4 #include "bus-common-errors.h"
   5 #include "bus-get-properties.h"
   6 #include "dbus-cgroup.h"
   7 #include "dbus-kill.h"
   8 #include "dbus-scope.h"
   9 #include "dbus-unit.h"
  10 #include "dbus-util.h"
  11 #include "dbus.h"
  12 #include "scope.h"
  13 #include "selinux-access.h"
  14 #include "unit.h"
  15
  16 int bus_scope_method_abandon(sd_bus_message *message, void *userdata, sd_bus_error *error) {
  17         Scope *s = userdata;
  18         int r;
  19
  20         assert(message);
  21         assert(s);
  22
  23         r = mac_selinux_unit_access_check(UNIT(s), message, "stop", error);
  24         if (r < 0)
  25                 return r;
  26
  27         r = bus_verify_manage_units_async(UNIT(s)->manager, message, error);
  28         if (r < 0)
  29                 return r;
  30         if (r == 0)
  31                 return 1; /* No authorization for now, but the async polkit stuff will call us again when it has it */
  32
  33         r = scope_abandon(s);
  34         if (r == -ESTALE)
  35                 return sd_bus_error_setf(error, BUS_ERROR_SCOPE_NOT_RUNNING, "Scope %s is not running, cannot abandon.", UNIT(s)->id);
  36         if (r < 0)
  37                 return r;
  38
  39         return sd_bus_reply_method_return(message, NULL);
  40 }
  41
  42 static BUS_DEFINE_PROPERTY_GET_ENUM(property_get_result, scope_result, ScopeResult);
  43
  44 const sd_bus_vtable bus_scope_vtable[] = {
  45         SD_BUS_VTABLE_START(0),
  46         SD_BUS_PROPERTY("Controller", "s", NULL, offsetof(Scope, controller), SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
  47         SD_BUS_PROPERTY("TimeoutStopUSec", "t", bus_property_get_usec, offsetof(Scope, timeout_stop_usec), SD_BUS_VTABLE_PROPERTY_CONST),
  48         SD_BUS_PROPERTY("Result", "s", property_get_result, offsetof(Scope, result), SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
  49         SD_BUS_PROPERTY("RuntimeMaxUSec", "t", bus_property_get_usec, offsetof(Scope, runtime_max_usec), SD_BUS_VTABLE_PROPERTY_CONST),
  50         SD_BUS_PROPERTY("RuntimeRandomizedExtraUSec", "t", bus_property_get_usec, offsetof(Scope, runtime_rand_extra_usec), SD_BUS_VTABLE_PROPERTY_CONST),
  51         SD_BUS_SIGNAL("RequestStop", NULL, 0),
  52         SD_BUS_METHOD("Abandon", NULL, NULL, bus_scope_method_abandon, SD_BUS_VTABLE_UNPRIVILEGED),
  53         SD_BUS_VTABLE_END
  54 };
  55
  56 static int bus_scope_set_transient_property(
  57                 Scope *s,
  58                 const char *name,
  59                 sd_bus_message *message,
  60                 UnitWriteFlags flags,
  61                 sd_bus_error *error) {
  62
  63         Unit *u = UNIT(s);
  64         int r;
  65
  66         assert(s);
  67         assert(name);
  68         assert(message);
  69
  70         flags |= UNIT_PRIVATE;
  71
  72         if (streq(name, "TimeoutStopUSec"))
  73                 return bus_set_transient_usec(u, name, &s->timeout_stop_usec, message, flags, error);
  74
  75         if (streq(name, "RuntimeMaxUSec"))
  76                 return bus_set_transient_usec(u, name, &s->runtime_max_usec, message, flags, error);
  77
  78         if (streq(name, "RuntimeRandomizedExtraUSec"))
  79                 return bus_set_transient_usec(u, name, &s->runtime_rand_extra_usec, message, flags, error);
  80
  81         if (streq(name, "PIDs")) {
  82                 _cleanup_(sd_bus_creds_unrefp) sd_bus_creds *creds = NULL;
  83                 unsigned n = 0;
  84
  85                 r = sd_bus_message_enter_container(message, 'a', "u");
  86                 if (r < 0)
  87                         return r;
  88
  89                 for (;;) {
  90                         uint32_t upid;
  91                         pid_t pid;
  92
  93                         r = sd_bus_message_read(message, "u", &upid);
  94                         if (r < 0)
  95                                 return r;
  96                         if (r == 0)
  97                                 break;
  98
  99                         if (upid == 0) {
 100                                 if (!creds) {
 101                                         r = sd_bus_query_sender_creds(message, SD_BUS_CREDS_PID, &creds);
 102                                         if (r < 0)
 103                                                 return r;
 104                                 }
 105
 106                                 r = sd_bus_creds_get_pid(creds, &pid);
 107                                 if (r < 0)
 108                                         return r;
 109                         } else
 110                                 pid = (uid_t) upid;
 111
 112                         r = unit_pid_attachable(u, pid, error);
 113                         if (r < 0)
 114                                 return r;
 115
 116                         if (!UNIT_WRITE_FLAGS_NOOP(flags)) {
 117                                 r = unit_watch_pid(u, pid, false);
 118                                 if (r < 0 && r != -EEXIST)
 119                                         return r;
 120                         }
 121
 122                         n++;
 123                 }
 124
 125                 r = sd_bus_message_exit_container(message);
 126                 if (r < 0)
 127                         return r;
 128
 129                 if (n <= 0)
 130                         return -EINVAL;
 131
 132                 return 1;
 133
 134         } else if (streq(name, "Controller")) {
 135                 const char *controller;
 136
 137                 /* We can't support direct connections with this, as direct connections know no service or unique name
 138                  * concept, but the Controller field stores exactly that. */
 139                 if (sd_bus_message_get_bus(message) != u->manager->api_bus)
 140                         return sd_bus_error_set(error, SD_BUS_ERROR_NOT_SUPPORTED, "Sorry, Controller= logic only supported via the bus.");
 141
 142                 r = sd_bus_message_read(message, "s", &controller);
 143                 if (r < 0)
 144                         return r;
 145
 146                 if (!isempty(controller) && !sd_bus_service_name_is_valid(controller))
 147                         return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Controller '%s' is not a valid bus name.", controller);
 148
 149                 if (!UNIT_WRITE_FLAGS_NOOP(flags)) {
 150                         r = free_and_strdup(&s->controller, empty_to_null(controller));
 151                         if (r < 0)
 152                                 return r;
 153                 }
 154
 155                 return 1;
 156         }
 157
 158         return 0;
 159 }
 160
 161 int bus_scope_set_property(
 162                 Unit *u,
 163                 const char *name,
 164                 sd_bus_message *message,
 165                 UnitWriteFlags flags,
 166                 sd_bus_error *error) {
 167
 168         Scope *s = SCOPE(u);
 169         int r;
 170
 171         assert(s);
 172         assert(name);
 173         assert(message);
 174
 175         r = bus_cgroup_set_property(u, &s->cgroup_context, name, message, flags, error);
 176         if (r != 0)
 177                 return r;
 178
 179         if (u->load_state == UNIT_STUB) {
 180                 /* While we are created we still accept PIDs */
 181
 182                 r = bus_scope_set_transient_property(s, name, message, flags, error);
 183                 if (r != 0)
 184                         return r;
 185
 186                 r = bus_kill_context_set_transient_property(u, &s->kill_context, name, message, flags, error);
 187                 if (r != 0)
 188                         return r;
 189         }
 190
 191         return 0;
 192 }
 193
 194 int bus_scope_commit_properties(Unit *u) {
 195         assert(u);
 196
 197         unit_realize_cgroup(u);
 198
 199         return 0;
 200 }
 201
 202 int bus_scope_send_request_stop(Scope *s) {
 203         _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = NULL;
 204         _cleanup_free_ char *p = NULL;
 205         int r;
 206
 207         assert(s);
 208
 209         if (!s->controller)
 210                 return 0;
 211
 212         p = unit_dbus_path(UNIT(s));
 213         if (!p)
 214                 return -ENOMEM;
 215
 216         r = sd_bus_message_new_signal(
 217                         UNIT(s)->manager->api_bus,
 218                         &m,
 219                         p,
 220                         "org.freedesktop.systemd1.Scope",
 221                         "RequestStop");
 222         if (r < 0)
 223                 return r;
 224
 225         return sd_bus_send_to(UNIT(s)->manager->api_bus, m, s->controller, NULL);
 226 }
 227
 228 static int on_controller_gone(sd_bus_track *track, void *userdata) {
 229         Scope *s = userdata;
 230
 231         assert(track);
 232
 233         if (s->controller) {
 234                 log_unit_debug(UNIT(s), "Controller %s disappeared from bus.", s->controller);
 235                 unit_add_to_dbus_queue(UNIT(s));
 236                 s->controller = mfree(s->controller);
 237         }
 238
 239         s->controller_track = sd_bus_track_unref(s->controller_track);
 240
 241         return 0;
 242 }
 243
 244 int bus_scope_track_controller(Scope *s) {
 245         int r;
 246
 247         assert(s);
 248
 249         if (!s->controller || s->controller_track)
 250                 return 0;
 251
 252         r = sd_bus_track_new(UNIT(s)->manager->api_bus, &s->controller_track, on_controller_gone, s);
 253         if (r < 0)
 254                 return r;
 255
 256         r = sd_bus_track_add_name(s->controller_track, s->controller);
 257         if (r < 0) {
 258                 s->controller_track = sd_bus_track_unref(s->controller_track);
 259                 return r;
 260         }
 261
 262         return 0;
 263 }