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-manager.h"
   9 #include "dbus-scope.h"
  10 #include "dbus-unit.h"
  11 #include "dbus-util.h"
  12 #include "dbus.h"
  13 #include "scope.h"
  14 #include "selinux-access.h"
  15 #include "unit.h"
  16
  17 int bus_scope_method_abandon(sd_bus_message *message, void *userdata, sd_bus_error *error) {
  18         Scope *s = ASSERT_PTR(userdata);
  19         int r;
  20
  21         assert(message);
  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 static BUS_DEFINE_SET_TRANSIENT_PARSE(oom_policy, OOMPolicy, oom_policy_from_string);
  44
  45 const sd_bus_vtable bus_scope_vtable[] = {
  46         SD_BUS_VTABLE_START(0),
  47         SD_BUS_PROPERTY("Controller", "s", NULL, offsetof(Scope, controller), SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
  48         SD_BUS_PROPERTY("TimeoutStopUSec", "t", bus_property_get_usec, offsetof(Scope, timeout_stop_usec), SD_BUS_VTABLE_PROPERTY_CONST),
  49         SD_BUS_PROPERTY("Result", "s", property_get_result, offsetof(Scope, result), SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
  50         SD_BUS_PROPERTY("RuntimeMaxUSec", "t", bus_property_get_usec, offsetof(Scope, runtime_max_usec), SD_BUS_VTABLE_PROPERTY_CONST),
  51         SD_BUS_PROPERTY("RuntimeRandomizedExtraUSec", "t", bus_property_get_usec, offsetof(Scope, runtime_rand_extra_usec), SD_BUS_VTABLE_PROPERTY_CONST),
  52         SD_BUS_PROPERTY("OOMPolicy", "s", bus_property_get_oom_policy, offsetof(Scope, oom_policy), SD_BUS_VTABLE_PROPERTY_CONST),
  53         SD_BUS_SIGNAL("RequestStop", NULL, 0),
  54         SD_BUS_METHOD("Abandon", NULL, NULL, bus_scope_method_abandon, SD_BUS_VTABLE_UNPRIVILEGED),
  55         SD_BUS_VTABLE_END
  56 };
  57
  58 static int bus_scope_set_transient_property(
  59                 Scope *s,
  60                 const char *name,
  61                 sd_bus_message *message,
  62                 UnitWriteFlags flags,
  63                 sd_bus_error *error) {
  64
  65         Unit *u = UNIT(s);
  66         int r;
  67
  68         assert(s);
  69         assert(name);
  70         assert(message);
  71
  72         flags |= UNIT_PRIVATE;
  73
  74         if (streq(name, "TimeoutStopUSec"))
  75                 return bus_set_transient_usec(u, name, &s->timeout_stop_usec, message, flags, error);
  76
  77         if (streq(name, "RuntimeMaxUSec"))
  78                 return bus_set_transient_usec(u, name, &s->runtime_max_usec, message, flags, error);
  79
  80         if (streq(name, "RuntimeRandomizedExtraUSec"))
  81                 return bus_set_transient_usec(u, name, &s->runtime_rand_extra_usec, message, flags, error);
  82
  83         if (streq(name, "OOMPolicy"))
  84                 return bus_set_transient_oom_policy(u, name, &s->oom_policy, message, flags, error);
  85
  86         if (streq(name, "PIDs")) {
  87                 _cleanup_(sd_bus_creds_unrefp) sd_bus_creds *creds = NULL;
  88                 unsigned n = 0;
  89
  90                 r = sd_bus_message_enter_container(message, 'a', "u");
  91                 if (r < 0)
  92                         return r;
  93
  94                 for (;;) {
  95                         uint32_t upid;
  96                         pid_t pid;
  97
  98                         r = sd_bus_message_read(message, "u", &upid);
  99                         if (r < 0)
 100                                 return r;
 101                         if (r == 0)
 102                                 break;
 103
 104                         if (upid == 0) {
 105                                 if (!creds) {
 106                                         r = sd_bus_query_sender_creds(message, SD_BUS_CREDS_PID, &creds);
 107                                         if (r < 0)
 108                                                 return r;
 109                                 }
 110
 111                                 r = sd_bus_creds_get_pid(creds, &pid);
 112                                 if (r < 0)
 113                                         return r;
 114                         } else
 115                                 pid = (uid_t) upid;
 116
 117                         r = unit_pid_attachable(u, pid, error);
 118                         if (r < 0)
 119                                 return r;
 120
 121                         if (!UNIT_WRITE_FLAGS_NOOP(flags)) {
 122                                 r = unit_watch_pid(u, pid, false);
 123                                 if (r < 0 && r != -EEXIST)
 124                                         return r;
 125                         }
 126
 127                         n++;
 128                 }
 129
 130                 r = sd_bus_message_exit_container(message);
 131                 if (r < 0)
 132                         return r;
 133
 134                 if (n <= 0)
 135                         return -EINVAL;
 136
 137                 return 1;
 138
 139         } else if (streq(name, "Controller")) {
 140                 const char *controller;
 141
 142                 /* We can't support direct connections with this, as direct connections know no service or unique name
 143                  * concept, but the Controller field stores exactly that. */
 144                 if (sd_bus_message_get_bus(message) != u->manager->api_bus)
 145                         return sd_bus_error_set(error, SD_BUS_ERROR_NOT_SUPPORTED, "Sorry, Controller= logic only supported via the bus.");
 146
 147                 r = sd_bus_message_read(message, "s", &controller);
 148                 if (r < 0)
 149                         return r;
 150
 151                 if (!isempty(controller) && !sd_bus_service_name_is_valid(controller))
 152                         return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Controller '%s' is not a valid bus name.", controller);
 153
 154                 if (!UNIT_WRITE_FLAGS_NOOP(flags)) {
 155                         r = free_and_strdup(&s->controller, empty_to_null(controller));
 156                         if (r < 0)
 157                                 return r;
 158                 }
 159
 160                 return 1;
 161         }
 162
 163         return 0;
 164 }
 165
 166 int bus_scope_set_property(
 167                 Unit *u,
 168                 const char *name,
 169                 sd_bus_message *message,
 170                 UnitWriteFlags flags,
 171                 sd_bus_error *error) {
 172
 173         Scope *s = SCOPE(u);
 174         int r;
 175
 176         assert(s);
 177         assert(name);
 178         assert(message);
 179
 180         r = bus_cgroup_set_property(u, &s->cgroup_context, name, message, flags, error);
 181         if (r != 0)
 182                 return r;
 183
 184         if (u->load_state == UNIT_STUB) {
 185                 /* While we are created we still accept PIDs */
 186
 187                 r = bus_scope_set_transient_property(s, name, message, flags, error);
 188                 if (r != 0)
 189                         return r;
 190
 191                 r = bus_kill_context_set_transient_property(u, &s->kill_context, name, message, flags, error);
 192                 if (r != 0)
 193                         return r;
 194
 195                 if (streq(name, "User"))
 196                         return bus_set_transient_user_relaxed(u, name, &s->user, message, flags, error);
 197
 198                 if (streq(name, "Group"))
 199                         return bus_set_transient_user_relaxed(u, name, &s->group, message, flags, error);
 200         }
 201
 202         return 0;
 203 }
 204
 205 int bus_scope_commit_properties(Unit *u) {
 206         assert(u);
 207
 208         unit_realize_cgroup(u);
 209
 210         return 0;
 211 }
 212
 213 int bus_scope_send_request_stop(Scope *s) {
 214         _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = NULL;
 215         _cleanup_free_ char *p = NULL;
 216         int r;
 217
 218         assert(s);
 219
 220         if (!s->controller)
 221                 return 0;
 222
 223         p = unit_dbus_path(UNIT(s));
 224         if (!p)
 225                 return -ENOMEM;
 226
 227         r = sd_bus_message_new_signal(
 228                         UNIT(s)->manager->api_bus,
 229                         &m,
 230                         p,
 231                         "org.freedesktop.systemd1.Scope",
 232                         "RequestStop");
 233         if (r < 0)
 234                 return r;
 235
 236         return sd_bus_send_to(UNIT(s)->manager->api_bus, m, s->controller, NULL);
 237 }
 238
 239 static int on_controller_gone(sd_bus_track *track, void *userdata) {
 240         Scope *s = userdata;
 241
 242         assert(track);
 243
 244         if (s->controller) {
 245                 log_unit_debug(UNIT(s), "Controller %s disappeared from bus.", s->controller);
 246                 unit_add_to_dbus_queue(UNIT(s));
 247                 s->controller = mfree(s->controller);
 248         }
 249
 250         s->controller_track = sd_bus_track_unref(s->controller_track);
 251
 252         return 0;
 253 }
 254
 255 int bus_scope_track_controller(Scope *s) {
 256         int r;
 257
 258         assert(s);
 259
 260         if (!s->controller || s->controller_track)
 261                 return 0;
 262
 263         r = sd_bus_track_new(UNIT(s)->manager->api_bus, &s->controller_track, on_controller_gone, s);
 264         if (r < 0)
 265                 return r;
 266
 267         r = sd_bus_track_add_name(s->controller_track, s->controller);
 268         if (r < 0) {
 269                 s->controller_track = sd_bus_track_unref(s->controller_track);
 270                 return r;
 271         }
 272
 273         return 0;
 274 }