src/bus-driverd/bus-driverd.c

   1 /***
   2   This file is part of systemd.
   3
   4   Copyright 2013 Daniel Mack
   5
   6   systemd is free software; you can redistribute it and/or modify it
   7   under the terms of the GNU Lesser General Public License as published by
   8   the Free Software Foundation; either version 2.1 of the License, or
   9   (at your option) any later version.
  10
  11   systemd is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   Lesser General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public License
  17   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  18 ***/
  19
  20 #include <stdlib.h>
  21 #include <stdbool.h>
  22 #include <unistd.h>
  23 #include <getopt.h>
  24 #include <locale.h>
  25 #include <string.h>
  26 #include <poll.h>
  27 #include <netdb.h>
  28 #include <sys/socket.h>
  29 #include <sys/un.h>
  30 #include <sys/timex.h>
  31 #include <sys/utsname.h>
  32 #include <unistd.h>
  33
  34 #include "kdbus.h"
  35 #include "sd-bus.h"
  36 #include "bus-internal.h"
  37
  38 #include "sd-daemon.h"
  39 #include "sd-event.h"
  40 #include "event-util.h"
  41 #include "bus-util.h"
  42 #include "bus-error.h"
  43 #include "bus-message.h"
  44 #include "bus-kernel.h"
  45 #include "socket-util.h"
  46 #include "util.h"
  47 #include "build.h"
  48 #include "strv.h"
  49 #include "sd-id128.h"
  50 #include "async.h"
  51 #include "hashmap.h"
  52 #include "def.h"
  53
  54 /*
  55  * TODO:
  56  *
  57  * AddMatch / RemoveMatch
  58  * ListActivatableNames
  59  * StartServiceByName
  60  */
  61
  62 static int driver_name_info_error(sd_bus *bus, sd_bus_message *m, const char *name, int error_code) {
  63
  64         if (error_code == -ENXIO || error_code == -ENOENT)
  65                 return sd_bus_reply_method_errorf(m, SD_BUS_ERROR_NAME_HAS_NO_OWNER,
  66                                                   "Could not get owner of name '%s': no such name",
  67                                                   name);
  68
  69         return sd_bus_reply_method_errno(m, error_code, NULL);
  70 }
  71
  72 static int driver_add_match(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
  73
  74         char *arg0, *match;
  75         int r;
  76
  77         r = sd_bus_message_read(m, "s", &arg0);
  78         if (r < 0)
  79                 return r;
  80
  81         match = strdup(arg0);
  82         if (!match)
  83                 return -ENOMEM;
  84
  85         /* FIXME */
  86
  87         return sd_bus_reply_method_return(m, NULL);
  88 }
  89
  90 static int driver_remove_match(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
  91
  92         char *arg0;
  93         int r;
  94
  95         r = sd_bus_message_read(m, "s", &arg0);
  96         if (r < 0)
  97                 return r;
  98
  99         /* FIXME */
 100
 101         return sd_bus_reply_method_return(m, NULL);
 102 }
 103
 104 static int driver_get_security_ctx(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
 105
 106         _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL;
 107         _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
 108         char *arg0;
 109         int r;
 110
 111         r = sd_bus_message_read(m, "s", &arg0);
 112         if (r < 0)
 113                 return r;
 114
 115         r = sd_bus_get_owner(bus, arg0, SD_BUS_CREDS_SELINUX_CONTEXT, &creds);
 116         if (r < 0) {
 117                 if (r == -ENOENT)
 118                         return driver_name_info_error(bus, m, arg0, r);
 119                 else
 120                         return r;
 121         }
 122
 123         r = sd_bus_message_new_method_return(m, &reply);
 124         if (r < 0)
 125                 return r;
 126
 127         r = sd_bus_message_append_array(reply, 'y', creds->label, strlen(creds->label));
 128         if (r < 0)
 129                 return r;
 130
 131         return sd_bus_send(bus, reply, NULL);
 132 }
 133
 134 static int driver_get_pid(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
 135
 136         _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL;
 137         char *arg0;
 138         int r;
 139
 140         r = sd_bus_message_read(m, "s", &arg0);
 141         if (r < 0)
 142                 return r;
 143
 144         r = sd_bus_get_owner(bus, arg0, SD_BUS_CREDS_PID, &creds);
 145         if (r < 0)
 146                 return r;
 147
 148         return sd_bus_reply_method_return(m, "u", creds->pid);
 149 }
 150
 151 static int driver_get_user(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
 152
 153         _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL;
 154         char *arg0;
 155         int r;
 156
 157         r = sd_bus_message_read(m, "s", &arg0);
 158         if (r < 0)
 159                 return r;
 160
 161         r = sd_bus_get_owner(bus, arg0, SD_BUS_CREDS_UID, &creds);
 162         if (r < 0) {
 163                 if (r == -ENOENT)
 164                         return driver_name_info_error(bus, m, arg0, r);
 165                 else
 166                         return r;
 167         }
 168
 169         return sd_bus_reply_method_return(m, "u", creds->uid);
 170 }
 171
 172 static int driver_get_id(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
 173
 174         sd_id128_t server_id;
 175         char buf[SD_ID128_STRING_MAX];
 176         int r;
 177
 178         r = sd_bus_get_server_id(bus, &server_id);
 179         if (r < 0)
 180                 return r;
 181
 182         return sd_bus_reply_method_return(m, "s", sd_id128_to_string(server_id, buf));
 183 }
 184
 185 static int driver_get_name_owner(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
 186
 187         _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL;
 188         char *arg0;
 189         int r;
 190
 191         r = sd_bus_message_read(m, "s", &arg0);
 192         if (r < 0)
 193                 return r;
 194
 195         r = sd_bus_get_owner(bus, arg0, SD_BUS_CREDS_UNIQUE_NAME, &creds);
 196         if (r < 0) {
 197                 if (r == -ENOENT)
 198                         return driver_name_info_error(bus, m, arg0, r);
 199                 else
 200                         return r;
 201         }
 202
 203         return sd_bus_reply_method_return(m, "s", creds->unique_name);
 204 }
 205
 206 static int driver_hello(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
 207
 208         return sd_bus_reply_method_return(m, "s", m->sender);
 209 }
 210
 211 static int driver_list_names(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
 212
 213         _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
 214         _cleanup_strv_free_ char **names = NULL;
 215         int r;
 216
 217         r = sd_bus_list_names(bus, &names, NULL);
 218         if (r < 0)
 219                 return r;
 220
 221         r = sd_bus_message_new_method_return(m, &reply);
 222         if (r < 0)
 223                 return r;
 224
 225         r = sd_bus_message_append_strv(reply, names);
 226         if (r < 0)
 227                 return r;
 228
 229         return sd_bus_send(bus, reply, NULL);
 230 }
 231
 232 static int driver_list_activatable_names(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
 233
 234         _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
 235         _cleanup_strv_free_ char **names = NULL;
 236         int r;
 237
 238         r = sd_bus_list_names(bus, NULL, &names);
 239         if (r < 0)
 240                 return r;
 241
 242         r = sd_bus_message_new_method_return(m, &reply);
 243         if (r < 0)
 244                 return r;
 245
 246         r = sd_bus_message_append_strv(reply, names);
 247         if (r < 0)
 248                 return r;
 249
 250         return sd_bus_send(bus, reply, NULL);
 251 }
 252
 253 static int driver_list_queued_owners(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
 254
 255         _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
 256         struct kdbus_cmd_name_list cmd = {};
 257         struct kdbus_name_list *name_list;
 258         struct kdbus_cmd_name *name;
 259         _cleanup_strv_free_ char **owners = NULL;
 260         char *arg0;
 261         int r;
 262
 263         r = sd_bus_message_read(m, "s", &arg0);
 264         if (r < 0)
 265                 return r;
 266
 267         cmd.flags = KDBUS_NAME_LIST_QUEUED;
 268
 269         r = ioctl(bus->input_fd, KDBUS_CMD_NAME_LIST, &cmd);
 270         if (r < 0)
 271                 return -errno;
 272
 273         name_list = (struct kdbus_name_list *) ((uint8_t *) bus->kdbus_buffer + cmd.offset);
 274
 275         KDBUS_ITEM_FOREACH(name, name_list, names) {
 276                 if (name->size > sizeof(*name) && !streq(name->name, arg0)) {
 277                         char *n;
 278
 279                         if (asprintf(&n, ":1.%llu", (unsigned long long) name->id) < 0)
 280                                 return -ENOMEM;
 281
 282                         r = strv_push(&owners, n);
 283                         if (r < 0) {
 284                                 free(n);
 285                                 return -ENOMEM;
 286                         }
 287                 }
 288         }
 289
 290         r = ioctl(sd_bus_get_fd(bus), KDBUS_CMD_FREE, &cmd.offset);
 291         if (r < 0)
 292                 return -errno;
 293
 294         r = sd_bus_message_new_method_return(m, &reply);
 295         if (r < 0)
 296                 return r;
 297
 298         r = sd_bus_message_append_strv(reply, owners);
 299         if (r < 0)
 300                 return r;
 301
 302         return sd_bus_send(bus, reply, NULL);
 303 }
 304
 305 static int driver_name_has_owner(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
 306
 307         char *arg0;
 308         int r;
 309
 310         r = sd_bus_message_read(m, "s", &arg0);
 311         if (r < 0)
 312                 return r;
 313
 314         r = sd_bus_get_owner(bus, arg0, 0, NULL);
 315         if (r < 0 && r != -ENOENT)
 316                 return r;
 317
 318         return sd_bus_reply_method_return(m, "b", r == 0);
 319 }
 320
 321 static int driver_request_name(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
 322
 323         struct kdbus_cmd_name *cmd_name;
 324         uint32_t flags;
 325         size_t size;
 326         uint64_t id;
 327         char *name;
 328         int r;
 329
 330         r = sd_bus_message_read(m, "su", &name, &flags);
 331         if (r < 0)
 332                 return r;
 333
 334         size = sizeof(*cmd_name) + strlen(name) + 1;
 335
 336         cmd_name = alloca(size);
 337         memset(cmd_name, 0, size);
 338         strcpy(cmd_name->name, name);
 339         cmd_name->size = size;
 340         kdbus_translate_request_name_flags(flags, (uint64_t *) &cmd_name->conn_flags);
 341
 342         /* This function is open-coded because we request the name 'on behalf'
 343          * of the requesting connection */
 344         r = bus_kernel_parse_unique_name(m->sender, &id);
 345         if (r < 0)
 346                 return r;
 347
 348         cmd_name->id = id;
 349
 350         r = ioctl(sd_bus_get_fd(bus), KDBUS_CMD_NAME_ACQUIRE, cmd_name);
 351         if (r < 0) {
 352                 if (errno == EEXIST)
 353                         return sd_bus_reply_method_return(m, "u", BUS_NAME_EXISTS);
 354                 else if (errno == EALREADY)
 355                         return sd_bus_reply_method_return(m, "u", BUS_NAME_ALREADY_OWNER);
 356                 else
 357                         return sd_bus_reply_method_return(m, "u", -errno);
 358         }
 359
 360         if (cmd_name->flags & KDBUS_NAME_IN_QUEUE)
 361                 return sd_bus_reply_method_return(m, "u", BUS_NAME_IN_QUEUE);
 362
 363         return sd_bus_reply_method_return(m, "u", BUS_NAME_PRIMARY_OWNER);
 364 }
 365
 366 static int driver_start_service_by_name(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
 367
 368         _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
 369         char *s;
 370         int r;
 371
 372         return sd_bus_reply_method_return(m, "u", 2);
 373
 374         r = sd_bus_message_read(m, "s", &s);
 375         if (r < 0)
 376                 return r;
 377
 378         /* FIXME */
 379
 380         return sd_bus_send(bus, reply, NULL);
 381 }
 382
 383 static int driver_unsupported(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
 384         return sd_bus_error_setf(error, SD_BUS_ERROR_NOT_SUPPORTED, "%s() is not supported", sd_bus_message_get_member(m));
 385 }
 386
 387 static const sd_bus_vtable driver_vtable[] = {
 388         SD_BUS_VTABLE_START(0),
 389         SD_BUS_METHOD("AddMatch", "s", NULL, driver_add_match, 0),
 390         SD_BUS_METHOD("GetConnectionSELinuxSecurityContext", "s", "ay", driver_get_security_ctx, 0),
 391         SD_BUS_METHOD("GetConnectionUnixProcessID", "s", "u", driver_get_pid, 0),
 392         SD_BUS_METHOD("GetConnectionUnixUser", "s", "u", driver_get_user, 0),
 393         SD_BUS_METHOD("GetId", NULL, "s", driver_get_id, 0),
 394         SD_BUS_METHOD("GetNameOwner", "s", "s", driver_get_name_owner, 0),
 395         SD_BUS_METHOD("Hello", NULL, "s", driver_hello, 0),
 396         SD_BUS_METHOD("ListActivatableNames", NULL, "as", driver_list_activatable_names, 0),
 397         SD_BUS_METHOD("ListNames", NULL, "as", driver_list_names, 0),
 398         SD_BUS_METHOD("ListQueuedOwners", "s", "as", driver_list_queued_owners, 0),
 399         SD_BUS_METHOD("NameHasOwner", "s", "b", driver_name_has_owner, 0),
 400         SD_BUS_METHOD("ReloadConfig", NULL, NULL, driver_unsupported, 0),
 401         SD_BUS_METHOD("RemoveMatch", "s", NULL, driver_remove_match, 0),
 402         SD_BUS_METHOD("RequestName", "su", "u", driver_request_name, 0),
 403         SD_BUS_METHOD("StartServiceByName", "su", "u", driver_start_service_by_name, 0),
 404         SD_BUS_METHOD("UpdateActivationEnvironment", "a{ss}", NULL, driver_unsupported, 0),
 405         SD_BUS_SIGNAL("NameAcquired", "s", 0),
 406         SD_BUS_SIGNAL("NameLost", "s", 0),
 407         SD_BUS_SIGNAL("NameOwnerChanged", "sss", 0),
 408         SD_BUS_VTABLE_END
 409 };
 410
 411 static int connect_bus(sd_event *event, sd_bus **_bus) {
 412         _cleanup_bus_unref_ sd_bus *bus = NULL;
 413         int r;
 414
 415         assert(event);
 416         assert(_bus);
 417
 418         r = sd_bus_default_system(&bus);
 419         if (r < 0) {
 420                 log_error("Failed to create bus: %s", strerror(-r));
 421                 return r;
 422         }
 423
 424         r = sd_bus_add_object_vtable(bus, "/org/freedesktop/DBus", "org.freedesktop.DBus", driver_vtable, NULL);
 425         if (r < 0) {
 426                 log_error("Failed to add manager object vtable: %s", strerror(-r));
 427                 return r;
 428         }
 429
 430         r = sd_bus_request_name(bus, "org.freedesktop.DBus", 0);
 431         if (r < 0) {
 432                 log_error("Unable to request name: %s\n", strerror(-r));
 433                 return r;
 434         }
 435
 436         r = sd_bus_attach_event(bus, event, 0);
 437         if (r < 0) {
 438                 log_error("Error %d while adding bus to even: %s", r, strerror(-r));
 439                 return r;
 440         }
 441
 442         *_bus = bus;
 443         bus = NULL;
 444
 445         return 0;
 446 }
 447
 448 int main(int argc, char *argv[]) {
 449         _cleanup_event_unref_ sd_event *event = NULL;
 450         _cleanup_bus_unref_ sd_bus *bus = NULL;
 451         int r;
 452
 453         log_set_target(LOG_TARGET_AUTO);
 454         log_parse_environment();
 455         log_open();
 456
 457         if (argc != 1) {
 458                 log_error("This program takes no arguments.");
 459                 r = -EINVAL;
 460                 goto finish;
 461         }
 462
 463         r = sd_event_default(&event);
 464         if (r < 0) {
 465                 log_error("Failed to allocate event loop: %s", strerror(-r));
 466                 goto finish;
 467         }
 468
 469         sd_event_set_watchdog(event, true);
 470
 471         r = connect_bus(event, &bus);
 472         if (r < 0)
 473                 goto finish;
 474
 475         r = bus_event_loop_with_idle(event, bus, "org.freedesktop.DBus", DEFAULT_EXIT_USEC);
 476         if (r < 0) {
 477                 log_error("Failed to run event loop: %s", strerror(-r));
 478                 goto finish;
 479         }
 480
 481 finish:
 482         return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
 483
 484 }