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
  33 #include "kdbus.h"
  34 #include "sd-bus.h"
  35 #include "bus-internal.h"
  36 #include "sd-daemon.h"
  37 #include "sd-event.h"
  38 #include "event-util.h"
  39 #include "bus-util.h"
  40 #include "bus-error.h"
  41 #include "bus-message.h"
  42 #include "bus-kernel.h"
  43 #include "socket-util.h"
  44 #include "util.h"
  45 #include "build.h"
  46 #include "strv.h"
  47 #include "sd-id128.h"
  48 #include "async.h"
  49 #include "hashmap.h"
  50 #include "def.h"
  51 #include "unit-name.h"
  52 #include "bus-control.h"
  53 #include "cgroup-util.h"
  54
  55 #define CLIENTS_MAX 1024
  56 #define MATCHES_MAX 1024
  57
  58 typedef struct Match Match;
  59 typedef struct Client Client;
  60 typedef struct Context Context;
  61
  62 struct Match {
  63         Client *client;
  64         char *match;
  65         uint64_t cookie;
  66         LIST_FIELDS(Match, matches);
  67 };
  68
  69 struct Client {
  70         Context *context;
  71         uint64_t id;
  72         uint64_t next_cookie;
  73         Hashmap *matches;
  74         unsigned n_matches;
  75         char *watch;
  76 };
  77
  78 struct Context {
  79         sd_bus *bus;
  80         sd_event *event;
  81         Hashmap *clients;
  82 };
  83
  84 static void match_free(Match *m) {
  85
  86         if (!m)
  87                 return;
  88
  89         if (m->client) {
  90                 Match *first;
  91
  92                 first = hashmap_get(m->client->matches, m->match);
  93                 LIST_REMOVE(matches, first, m);
  94                 if (first)
  95                         assert_se(hashmap_replace(m->client->matches, first->match, first) >= 0);
  96                 else
  97                         hashmap_remove(m->client->matches, m->match);
  98
  99                 m->client->n_matches--;
 100         }
 101
 102         free(m->match);
 103         free(m);
 104 }
 105
 106 static int match_new(Client *c, struct bus_match_component *components, unsigned n_components, Match **_m) {
 107         Match *m, *first;
 108         int r;
 109
 110         assert(c);
 111         assert(_m);
 112
 113         r = hashmap_ensure_allocated(&c->matches, string_hash_func, string_compare_func);
 114         if (r < 0)
 115                 return r;
 116
 117         m = new0(Match, 1);
 118         if (!m)
 119                 return -ENOMEM;
 120
 121         m->match = bus_match_to_string(components, n_components);
 122         if (!m->match) {
 123                 r = -ENOMEM;
 124                 goto fail;
 125         }
 126
 127         m->cookie = ++c->next_cookie;
 128
 129         first = hashmap_get(c->matches, m->match);
 130         LIST_PREPEND(matches, first, m);
 131         r = hashmap_replace(c->matches, m->match, first);
 132         if (r < 0) {
 133                 LIST_REMOVE(matches, first, m);
 134                 goto fail;
 135         }
 136
 137         m->client = c;
 138         c->n_matches++;
 139
 140         *_m = m;
 141         m = NULL;
 142
 143         return 0;
 144
 145 fail:
 146         match_free(m);
 147         return r;
 148 }
 149
 150 static int on_name_owner_changed(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error);
 151
 152 static void client_free(Client *c) {
 153         Match *m;
 154
 155         if (!c)
 156                 return;
 157
 158         if (c->context) {
 159                 if (c->watch)
 160                         sd_bus_remove_match(c->context->bus, c->watch, on_name_owner_changed, c);
 161
 162                 assert_se(hashmap_remove(c->context->clients, &c->id) == c);
 163         }
 164
 165         while ((m = hashmap_first(c->matches)))
 166                 match_free(m);
 167
 168         hashmap_free(c->matches);
 169         free(c->watch);
 170
 171         free(c);
 172 }
 173
 174 static int on_name_owner_changed(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
 175         Client *c = userdata;
 176
 177         assert(bus);
 178         assert(m);
 179
 180         client_free(c);
 181         return 0;
 182 }
 183
 184 static int client_acquire(Context *context, uint64_t id, Client **_c) {
 185         char *watch = NULL;
 186         Client *c;
 187         int r;
 188
 189         assert(context);
 190         assert(_c);
 191
 192         c = hashmap_get(context->clients, &id);
 193         if (c) {
 194                 *_c = c;
 195                 return 0;
 196         }
 197
 198         if (hashmap_size(context->clients) >= CLIENTS_MAX)
 199                 return -ENOBUFS;
 200
 201         r = hashmap_ensure_allocated(&context->clients, uint64_hash_func, uint64_compare_func);
 202         if (r < 0)
 203                 return r;
 204
 205         c = new0(Client, 1);
 206         if (!c)
 207                 return -ENOMEM;
 208
 209         c->id = id;
 210
 211         r = hashmap_put(context->clients, &c->id, c);
 212         if (r < 0)
 213                 goto fail;
 214
 215         c->context = context;
 216
 217         if (asprintf(&watch,
 218                      "type='signal',"
 219                      "sender='org.freedesktop.DBus',"
 220                      "path='/org/freedesktop/DBus',"
 221                      "interface='org.freedesktop.DBus',"
 222                      "member='NameOwnerChanged',"
 223                      "arg0=':1.%llu'", (unsigned long long) id) < 0) {
 224                 r = -ENOMEM;
 225                 goto fail;
 226         }
 227
 228         r = sd_bus_add_match(context->bus, watch, on_name_owner_changed, c);
 229         if (r < 0) {
 230                 free(watch);
 231                 goto fail;
 232         }
 233
 234         c->watch = watch;
 235
 236         *_c = c;
 237         return 0;
 238
 239 fail:
 240         client_free(c);
 241         return r;
 242 }
 243
 244 static int driver_add_match(sd_bus *bus, sd_bus_message *message, void *userdata, sd_bus_error *error) {
 245
 246         struct bus_match_component *components = NULL;
 247         Context *context = userdata;
 248         unsigned n_components = 0;
 249         Match *m = NULL;
 250         Client *c = NULL;
 251         char *arg0;
 252         uint64_t id;
 253         int r;
 254
 255         assert(bus);
 256         assert(message);
 257         assert(context);
 258
 259         r = sd_bus_message_read(message, "s", &arg0);
 260         if (r < 0)
 261                 return r;
 262
 263         r = bus_kernel_parse_unique_name(message->sender, &id);
 264         if (r < 0)
 265                 return r;
 266
 267         r = client_acquire(context, id, &c);
 268         if (r == -ENOBUFS)
 269                 return sd_bus_error_setf(error, SD_BUS_ERROR_LIMITS_EXCEEDED, "Reached limit of %u clients", CLIENTS_MAX);
 270         if (r < 0)
 271                 return r;
 272
 273         if (c->n_matches >= MATCHES_MAX) {
 274                 r = sd_bus_error_setf(error, SD_BUS_ERROR_LIMITS_EXCEEDED, "Reached limit of %u matches per client", MATCHES_MAX);
 275                 goto fail;
 276         }
 277
 278         r = bus_match_parse(arg0, &components, &n_components);
 279         if (r < 0) {
 280                 r = sd_bus_error_setf(error, SD_BUS_ERROR_MATCH_RULE_INVALID, "Match rule \"%s\" is not valid", arg0);
 281                 goto fail;
 282         }
 283
 284         r = match_new(c, components, n_components, &m);
 285         if (r < 0)
 286                 goto fail;
 287
 288         r = bus_add_match_internal_kernel(bus, id, components, n_components, m->cookie);
 289         if (r < 0)
 290                 goto fail;
 291
 292         bus_match_parse_free(components, n_components);
 293
 294         return sd_bus_reply_method_return(message, NULL);
 295
 296 fail:
 297         bus_match_parse_free(components, n_components);
 298
 299         match_free(m);
 300
 301         if (c->n_matches <= 0)
 302                 client_free(c);
 303
 304         return r;
 305 }
 306
 307 static int driver_remove_match(sd_bus *bus, sd_bus_message *message, void *userdata, sd_bus_error *error) {
 308
 309         struct bus_match_component *components = NULL;
 310         _cleanup_free_ char *normalized = NULL;
 311         Context *context = userdata;
 312         unsigned n_components = 0;
 313         Client *c = NULL;
 314         Match *m = NULL;
 315         char *arg0;
 316         uint64_t id;
 317         int r;
 318
 319         assert(bus);
 320         assert(message);
 321         assert(context);
 322
 323         r = sd_bus_message_read(message, "s", &arg0);
 324         if (r < 0)
 325                 return r;
 326
 327         r = bus_kernel_parse_unique_name(message->sender, &id);
 328         if (r < 0)
 329                 return r;
 330
 331         c = hashmap_get(context->clients, &id);
 332         if (!c)
 333                 return sd_bus_error_setf(error, SD_BUS_ERROR_MATCH_RULE_NOT_FOUND, "You have not registered any matches.");
 334
 335         r = bus_match_parse(arg0, &components, &n_components);
 336         if (r < 0) {
 337                 r = sd_bus_error_setf(error, SD_BUS_ERROR_MATCH_RULE_INVALID, "Match rule \"%s\" is not valid", arg0);
 338                 goto finish;
 339         }
 340
 341         normalized = bus_match_to_string(components, n_components);
 342         if (!normalized) {
 343                 r = -ENOMEM;
 344                 goto finish;
 345         }
 346
 347         m = hashmap_get(c->matches, normalized);
 348         if (!m) {
 349                 r = sd_bus_error_setf(error, SD_BUS_ERROR_MATCH_RULE_NOT_FOUND, "Match rule \"%s\" not found.", normalized);
 350                 goto finish;
 351         }
 352
 353         bus_remove_match_internal_kernel(bus, id, m->cookie);
 354         match_free(m);
 355
 356         r = sd_bus_reply_method_return(message, NULL);
 357
 358 finish:
 359         bus_match_parse_free(components, n_components);
 360
 361         if (c->n_matches <= 0)
 362                 client_free(c);
 363
 364         return r;
 365 }
 366
 367 static int get_creds_by_name(sd_bus *bus, const char *name, uint64_t mask, sd_bus_creds **_creds, sd_bus_error *error) {
 368         _cleanup_bus_creds_unref_ sd_bus_creds *c = NULL;
 369         int r;
 370
 371         assert(bus);
 372         assert(name);
 373         assert(_creds);
 374
 375         assert_return(service_name_is_valid(name), -EINVAL);
 376
 377         r = sd_bus_get_owner(bus, name, mask, &c);
 378         if (r == -ENOENT || r == -ENXIO)
 379                 return sd_bus_error_setf(error, SD_BUS_ERROR_NAME_HAS_NO_OWNER, "Name %s is currently not owned by anyone.", name);
 380         if (r < 0)
 381                 return r;
 382
 383         if ((c->mask & mask) != mask)
 384                 return -ENOTSUP;
 385
 386         *_creds = c;
 387         c = NULL;
 388
 389         return 0;
 390 }
 391
 392
 393 static int get_creds_by_message(sd_bus *bus, sd_bus_message *m, uint64_t mask, sd_bus_creds **_creds, sd_bus_error *error) {
 394         const char *name;
 395         int r;
 396
 397         assert(bus);
 398         assert(m);
 399         assert(_creds);
 400
 401         r = sd_bus_message_read(m, "s", &name);
 402         if (r < 0)
 403                 return r;
 404
 405         return get_creds_by_name(bus, name, mask, _creds, error);
 406 }
 407
 408 static int driver_get_security_context(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
 409         _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
 410         _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL;
 411         int r;
 412
 413         r = get_creds_by_message(bus, m, SD_BUS_CREDS_SELINUX_CONTEXT, &creds, error);
 414         if (r < 0)
 415                 return r;
 416
 417         r = sd_bus_message_new_method_return(m, &reply);
 418         if (r < 0)
 419                 return r;
 420
 421         r = sd_bus_message_append_array(reply, 'y', creds->label, strlen(creds->label));
 422         if (r < 0)
 423                 return r;
 424
 425         return sd_bus_send(bus, reply, NULL);
 426 }
 427
 428 static int driver_get_pid(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
 429         _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL;
 430         int r;
 431
 432         r = get_creds_by_message(bus, m, SD_BUS_CREDS_PID, &creds, error);
 433         if (r < 0)
 434                 return r;
 435
 436         return sd_bus_reply_method_return(m, "u", (uint32_t) creds->pid);
 437 }
 438
 439 static int driver_get_user(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
 440         _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL;
 441         int r;
 442
 443         r = get_creds_by_message(bus, m, SD_BUS_CREDS_UID, &creds, error);
 444         if (r < 0)
 445                 return r;
 446
 447         return sd_bus_reply_method_return(m, "u", (uint32_t) creds->uid);
 448 }
 449
 450 static int driver_get_name_owner(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
 451         _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL;
 452         const char *name;
 453         int r;
 454
 455         r = sd_bus_message_read(m, "s", &name);
 456         if (r < 0)
 457                 return r;
 458
 459         /* Here's a special exception for compatibility with dbus1:
 460          * the bus name of the driver is owned by itself, not by a
 461          * unique ID. */
 462         if (streq(name, "org.freedesktop.DBus"))
 463                 return sd_bus_reply_method_return(m, "s", "org.freedesktop.DBus");
 464
 465         r = get_creds_by_name(bus, name, SD_BUS_CREDS_UNIQUE_NAME, &creds, error);
 466         if (r < 0)
 467                 return r;
 468
 469         return sd_bus_reply_method_return(m, "s", creds->unique_name);
 470 }
 471
 472 static int driver_get_id(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
 473         sd_id128_t server_id;
 474         char buf[SD_ID128_STRING_MAX];
 475         int r;
 476
 477         r = sd_bus_get_server_id(bus, &server_id);
 478         if (r < 0)
 479                 return r;
 480
 481         return sd_bus_reply_method_return(m, "s", sd_id128_to_string(server_id, buf));
 482 }
 483
 484 static int driver_hello(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
 485         return sd_bus_reply_method_return(m, "s", m->sender);
 486 }
 487
 488 static int return_strv(sd_bus *bus, sd_bus_message *m, char **l) {
 489         _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
 490         int r;
 491
 492         r = sd_bus_message_new_method_return(m, &reply);
 493         if (r < 0)
 494                 return r;
 495
 496         r = sd_bus_message_append_strv(reply, l);
 497         if (r < 0)
 498                 return r;
 499
 500         return sd_bus_send(bus, reply, NULL);
 501 }
 502
 503 static int driver_list_names(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
 504         _cleanup_strv_free_ char **names = NULL;
 505         int r;
 506
 507         r = sd_bus_list_names(bus, &names, NULL);
 508         if (r < 0)
 509                 return r;
 510
 511         /* Let's sort the names list to make it stable */
 512         strv_sort(names);
 513
 514         return return_strv(bus, m, names);
 515 }
 516
 517 static int driver_list_activatable_names(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
 518         _cleanup_strv_free_ char **names = NULL;
 519         int r;
 520
 521         r = sd_bus_list_names(bus, NULL, &names);
 522         if (r < 0)
 523                 return r;
 524
 525         /* Let's sort the names list to make it stable */
 526         strv_sort(names);
 527
 528         return return_strv(bus, m, names);
 529 }
 530
 531 static int driver_list_queued_owners(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
 532         struct kdbus_cmd_name_list cmd = {};
 533         struct kdbus_name_list *name_list;
 534         struct kdbus_cmd_name *name;
 535         _cleanup_strv_free_ char **owners = NULL;
 536         char *arg0;
 537         int r;
 538
 539         r = sd_bus_message_read(m, "s", &arg0);
 540         if (r < 0)
 541                 return r;
 542
 543         assert_return(service_name_is_valid(arg0), -EINVAL);
 544
 545         cmd.flags = KDBUS_NAME_LIST_QUEUED;
 546
 547         r = ioctl(bus->input_fd, KDBUS_CMD_NAME_LIST, &cmd);
 548         if (r < 0)
 549                 return -errno;
 550
 551         name_list = (struct kdbus_name_list *) ((uint8_t *) bus->kdbus_buffer + cmd.offset);
 552
 553         KDBUS_ITEM_FOREACH(name, name_list, names) {
 554                 char *n;
 555
 556                 if (name->size <= sizeof(*name))
 557                         continue;
 558
 559                 if (!streq(name->name, arg0))
 560                         continue;
 561
 562                 if (asprintf(&n, ":1.%llu", (unsigned long long) name->owner_id) < 0)
 563                         return -ENOMEM;
 564
 565                 r = strv_consume(&owners, n);
 566                 if (r < 0)
 567                         return r;
 568         }
 569
 570         r = ioctl(bus->input_fd, KDBUS_CMD_FREE, &cmd.offset);
 571         if (r < 0)
 572                 return -errno;
 573
 574         return return_strv(bus, m, owners);
 575 }
 576
 577 static int driver_name_has_owner(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
 578         const char *name;
 579         int r;
 580
 581         r = sd_bus_message_read(m, "s", &name);
 582         if (r < 0)
 583                 return r;
 584
 585         assert_return(service_name_is_valid(name), -EINVAL);
 586
 587         r = sd_bus_get_owner(bus, name, 0, NULL);
 588         if (r < 0 && r != -ENOENT && r != -ENXIO)
 589                 return r;
 590
 591         return sd_bus_reply_method_return(m, "b", r >= 0);
 592 }
 593
 594 static int driver_request_name(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
 595         struct kdbus_cmd_name *n;
 596         uint32_t flags;
 597         size_t size, l;
 598         uint64_t id;
 599         const char *name;
 600         int r;
 601
 602         r = sd_bus_message_read(m, "su", &name, &flags);
 603         if (r < 0)
 604                 return r;
 605
 606         assert_return(service_name_is_valid(name), -EINVAL);
 607         assert_return((flags & ~(BUS_NAME_ALLOW_REPLACEMENT|BUS_NAME_REPLACE_EXISTING|BUS_NAME_DO_NOT_QUEUE)) == 0, -EINVAL);
 608
 609         l = strlen(name);
 610         size = offsetof(struct kdbus_cmd_name, name) + l + 1;
 611         n = alloca0(size);
 612         n->size = size;
 613         memcpy(n->name, name, l+1);
 614         kdbus_translate_request_name_flags(flags, (uint64_t *) &n->flags);
 615
 616         /* This function is open-coded because we request the name 'on behalf'
 617          * of the requesting connection */
 618         r = bus_kernel_parse_unique_name(m->sender, &id);
 619         if (r < 0)
 620                 return r;
 621
 622         n->owner_id = id;
 623
 624         r = ioctl(bus->input_fd, KDBUS_CMD_NAME_ACQUIRE, n);
 625         if (r < 0) {
 626                 if (errno == EEXIST)
 627                         return sd_bus_reply_method_return(m, "u", BUS_NAME_EXISTS);
 628                 if (errno == EALREADY)
 629                         return sd_bus_reply_method_return(m, "u", BUS_NAME_ALREADY_OWNER);
 630
 631                 return -errno;
 632         }
 633
 634         if (n->flags & KDBUS_NAME_IN_QUEUE)
 635                 return sd_bus_reply_method_return(m, "u", BUS_NAME_IN_QUEUE);
 636
 637         return sd_bus_reply_method_return(m, "u", BUS_NAME_PRIMARY_OWNER);
 638 }
 639
 640 static int driver_release_name(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
 641         struct kdbus_cmd_name *n;
 642         const char *name;
 643         size_t l, size;
 644         uint64_t id;
 645         int r;
 646
 647         r = sd_bus_message_read(m, "s", &name);
 648         if (r < 0)
 649                 return r;
 650
 651         assert_return(service_name_is_valid(name), -EINVAL);
 652
 653         l = strlen(name);
 654         size = offsetof(struct kdbus_cmd_name, name) + l + 1;
 655         n = alloca0(size);
 656         n->size = size;
 657         memcpy(n->name, name, l+1);
 658
 659         /* This function is open-coded because we request the name 'on behalf'
 660          * of the requesting connection */
 661         r = bus_kernel_parse_unique_name(m->sender, &id);
 662         if (r < 0)
 663                 return r;
 664
 665         n->owner_id = id;
 666
 667         r = ioctl(bus->input_fd, KDBUS_CMD_NAME_RELEASE, n);
 668         if (r < 0) {
 669                 if (errno == ESRCH)
 670                         return sd_bus_reply_method_return(m, "u", BUS_NAME_NON_EXISTENT);
 671                 if (errno == EADDRINUSE)
 672                         return sd_bus_reply_method_return(m, "u", BUS_NAME_NOT_OWNER);
 673                 return -errno;
 674         }
 675
 676         return sd_bus_reply_method_return(m, "u", BUS_NAME_RELEASED);
 677 }
 678
 679 static int driver_start_service_by_name(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
 680         _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
 681         _cleanup_strv_free_ char **t = NULL;
 682         _cleanup_free_ char *path = NULL;
 683         uint32_t flags;
 684         char *name, *u;
 685         int r;
 686
 687         r = sd_bus_message_read(m, "su", &name, &flags);
 688         if (r < 0)
 689                 return r;
 690
 691         assert_return(service_name_is_valid(name), -EINVAL);
 692         assert_return(flags == 0, -ENOTSUP);
 693
 694         r = sd_bus_get_owner(bus, name, 0, NULL);
 695         if (r >= 0)
 696                 return sd_bus_reply_method_return(m, "u", BUS_START_REPLY_ALREADY_RUNNING);
 697         if (r != -ENOENT)
 698                 return r;
 699
 700         u = strappenda(name, ".busname");
 701
 702         path = unit_dbus_path_from_name(u);
 703         if (!path)
 704                 return -ENOMEM;
 705
 706         r = sd_bus_get_property_strv(
 707                         bus,
 708                         "org.freedesktop.systemd1",
 709                         path,
 710                         "org.freedesktop.systemd1.Unit",
 711                         "Triggers",
 712                         error,
 713                         &t);
 714         if (r < 0)
 715                 return r;
 716
 717         if (!t || !t[0] || t[1])
 718                 return sd_bus_error_setf(error, SD_BUS_ERROR_SERVICE_UNKNOWN, "Bus name %s not found.", name);
 719
 720         r = sd_bus_call_method(
 721                         bus,
 722                         "org.freedesktop.systemd1",
 723                         "/org/freedesktop/systemd1",
 724                         "org.freedesktop.systemd1.Manager",
 725                         "StartUnit",
 726                         error,
 727                         &reply,
 728                         "ss",
 729                         t[0],
 730                         "replace");
 731         if (r < 0)
 732                 return r;
 733
 734         return sd_bus_reply_method_return(m, "u", BUS_START_REPLY_SUCCESS);
 735 }
 736
 737 static int driver_update_environment(sd_bus*bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
 738         _cleanup_bus_message_unref_ sd_bus_message *msg = NULL;
 739         _cleanup_strv_free_ char **args = NULL;
 740         int r;
 741
 742         r = sd_bus_message_enter_container(m, SD_BUS_TYPE_ARRAY, "{ss}");
 743         if (r < 0)
 744                 return r;
 745
 746        while ((r = sd_bus_message_enter_container(m, SD_BUS_TYPE_DICT_ENTRY, "ss")) > 0) {
 747                 _cleanup_free_ char *s = NULL;
 748                 const char *key;
 749                 const char *value;
 750
 751                 r = sd_bus_message_read(m, "ss", &key, &value);
 752                 if (r < 0)
 753                         return r;
 754
 755                 s = strjoin(key, "=", value, NULL);
 756                 if (!s)
 757                         return ENOMEM;
 758
 759                 r  = strv_extend(&args, s);
 760                 if (r < 0)
 761                         return r;
 762
 763                 r = sd_bus_message_exit_container(m);
 764                 if (r < 0)
 765                         return r;
 766         }
 767
 768         r = sd_bus_message_exit_container(m);
 769         if (r < 0)
 770                 return r;
 771
 772         if (!args)
 773                 return -EINVAL;
 774
 775         r = sd_bus_message_new_method_call(
 776                         bus,
 777                         &msg,
 778                         "org.freedesktop.systemd1",
 779                         "/org/freedesktop/systemd1",
 780                         "org.freedesktop.systemd1.Manager",
 781                         "SetEnvironment");
 782         if (r < 0)
 783                 return r;
 784
 785         r = sd_bus_message_append_strv(msg, args);
 786         if (r < 0)
 787                 return r;
 788
 789         r = sd_bus_call(bus, msg, 0, NULL, NULL);
 790         if (r < 0)
 791                 return r;
 792
 793         return sd_bus_reply_method_return(m, NULL);
 794 }
 795
 796 static int driver_unsupported(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) {
 797         return sd_bus_error_setf(error, SD_BUS_ERROR_NOT_SUPPORTED, "%s() is not supported", sd_bus_message_get_member(m));
 798 }
 799
 800 static const sd_bus_vtable driver_vtable[] = {
 801         SD_BUS_VTABLE_START(0),
 802         SD_BUS_METHOD("AddMatch", "s", NULL, driver_add_match, SD_BUS_VTABLE_UNPRIVILEGED),
 803         SD_BUS_METHOD("GetConnectionSELinuxSecurityContext", "s", "ay", driver_get_security_context, SD_BUS_VTABLE_UNPRIVILEGED),
 804         SD_BUS_METHOD("GetConnectionUnixProcessID", "s", "u", driver_get_pid, SD_BUS_VTABLE_UNPRIVILEGED),
 805         SD_BUS_METHOD("GetConnectionUnixUser", "s", "u", driver_get_user, SD_BUS_VTABLE_UNPRIVILEGED),
 806         SD_BUS_METHOD("GetId", NULL, "s", driver_get_id, SD_BUS_VTABLE_UNPRIVILEGED),
 807         SD_BUS_METHOD("GetNameOwner", "s", "s", driver_get_name_owner, SD_BUS_VTABLE_UNPRIVILEGED),
 808         SD_BUS_METHOD("Hello", NULL, "s", driver_hello, SD_BUS_VTABLE_UNPRIVILEGED),
 809         SD_BUS_METHOD("ListActivatableNames", NULL, "as", driver_list_activatable_names, SD_BUS_VTABLE_UNPRIVILEGED),
 810         SD_BUS_METHOD("ListNames", NULL, "as", driver_list_names, SD_BUS_VTABLE_UNPRIVILEGED),
 811         SD_BUS_METHOD("ListQueuedOwners", "s", "as", driver_list_queued_owners, SD_BUS_VTABLE_UNPRIVILEGED),
 812         SD_BUS_METHOD("NameHasOwner", "s", "b", driver_name_has_owner, SD_BUS_VTABLE_UNPRIVILEGED),
 813         SD_BUS_METHOD("ReleaseName", "s", "u", driver_release_name, SD_BUS_VTABLE_UNPRIVILEGED),
 814         SD_BUS_METHOD("ReloadConfig", NULL, NULL, driver_unsupported, SD_BUS_VTABLE_DEPRECATED),
 815         SD_BUS_METHOD("RemoveMatch", "s", NULL, driver_remove_match, SD_BUS_VTABLE_UNPRIVILEGED),
 816         SD_BUS_METHOD("RequestName", "su", "u", driver_request_name, SD_BUS_VTABLE_UNPRIVILEGED),
 817         SD_BUS_METHOD("StartServiceByName", "su", "u", driver_start_service_by_name, SD_BUS_VTABLE_UNPRIVILEGED),
 818         SD_BUS_METHOD("UpdateActivationEnvironment", "a{ss}", NULL, driver_update_environment, 0),
 819         SD_BUS_SIGNAL("NameAcquired", "s", SD_BUS_VTABLE_DEPRECATED),
 820         SD_BUS_SIGNAL("NameLost", "s", SD_BUS_VTABLE_DEPRECATED),
 821         SD_BUS_SIGNAL("NameOwnerChanged", "sss", 0),
 822         SD_BUS_VTABLE_END
 823 };
 824
 825 static int find_object(
 826                 sd_bus *bus,
 827                 const char *path,
 828                 const char *interface,
 829                 void *userdata,
 830                 void **ret_found,
 831                 sd_bus_error *ret_error) {
 832
 833         /* We support the driver interface on exactly two different
 834          * paths: the root and the entry point object. This is a bit
 835          * different from the original dbus-daemon which supported it
 836          * on any path. */
 837
 838         if (streq_ptr(path, "/"))
 839                 return 1;
 840
 841         if (streq_ptr(path, "/org/freedesktop/DBus"))
 842                 return 1;
 843
 844         return 0;
 845 }
 846
 847 static int node_enumerator(
 848                 sd_bus *bus,
 849                 const char *path,
 850                 void *userdata,
 851                 char ***ret_nodes,
 852                 sd_bus_error *ret_error) {
 853
 854         char **l;
 855
 856         l = strv_new("/", "/org/freedesktop/DBus", NULL);
 857         if (!l)
 858                 return -ENOMEM;
 859
 860         *ret_nodes = l;
 861         return 0;
 862 }
 863
 864 static int connect_bus(Context *c) {
 865         int r;
 866
 867         assert(c);
 868
 869         r = sd_bus_default(&c->bus);
 870         if (r < 0) {
 871                 log_error("Failed to create bus: %s", strerror(-r));
 872                 return r;
 873         }
 874
 875         if (!c->bus->is_kernel) {
 876                 log_error("Not running on kdbus");
 877                 return -EPERM;
 878         }
 879
 880         r = sd_bus_add_fallback_vtable(c->bus, "/", "org.freedesktop.DBus", driver_vtable, find_object, c);
 881         if (r < 0) {
 882                 log_error("Failed to add manager object vtable: %s", strerror(-r));
 883                 return r;
 884         }
 885
 886         r = sd_bus_add_node_enumerator(c->bus, "/", node_enumerator, c);
 887         if (r < 0) {
 888                 log_error("Failed to add node enumerator: %s", strerror(-r));
 889                 return r;
 890         }
 891
 892         r = sd_bus_request_name(c->bus, "org.freedesktop.DBus", 0);
 893         if (r < 0) {
 894                 log_error("Unable to request name: %s", strerror(-r));
 895                 return r;
 896         }
 897
 898         r = sd_bus_attach_event(c->bus, c->event, 0);
 899         if (r < 0) {
 900                 log_error("Error while adding bus to event loop: %s", strerror(-r));
 901                 return r;
 902         }
 903
 904         return 0;
 905 }
 906
 907 static bool check_idle(void *userdata) {
 908         Context *c = userdata;
 909         assert(c);
 910
 911         return hashmap_isempty(c->clients);
 912 }
 913
 914 int main(int argc, char *argv[]) {
 915         Context context = {};
 916         Client *c;
 917         int r;
 918
 919         log_set_target(LOG_TARGET_AUTO);
 920         log_parse_environment();
 921         log_open();
 922
 923         if (argc != 1) {
 924                 log_error("This program takes no arguments.");
 925                 r = -EINVAL;
 926                 goto finish;
 927         }
 928
 929         r = sd_event_default(&context.event);
 930         if (r < 0) {
 931                 log_error("Failed to allocate event loop: %s", strerror(-r));
 932                 goto finish;
 933         }
 934
 935         sd_event_set_watchdog(context.event, true);
 936
 937         r = connect_bus(&context);
 938         if (r < 0)
 939                 goto finish;
 940
 941         r = bus_event_loop_with_idle(context.event, context.bus, "org.freedesktop.DBus", DEFAULT_EXIT_USEC, check_idle, &context);
 942         if (r < 0) {
 943                 log_error("Failed to run event loop: %s", strerror(-r));
 944                 goto finish;
 945         }
 946
 947 finish:
 948         while ((c = hashmap_first(context.clients)))
 949                 client_free(c);
 950
 951         sd_bus_unref(context.bus);
 952         sd_event_unref(context.event);
 953
 954         return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
 955 }