src/resolve/resolved-manager.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2
   3 #include <fcntl.h>
   4 #include <netinet/in.h>
   5 #include <poll.h>
   6 #include <sys/ioctl.h>
   7 #include <sys/stat.h>
   8 #include <sys/types.h>
   9 #include <unistd.h>
  10
  11 #if HAVE_LIBIDN2
  12 #include <idn2.h>
  13 #endif
  14
  15 #include "af-list.h"
  16 #include "alloc-util.h"
  17 #include "bus-polkit.h"
  18 #include "dirent-util.h"
  19 #include "dns-domain.h"
  20 #include "fd-util.h"
  21 #include "fileio.h"
  22 #include "hostname-util.h"
  23 #include "io-util.h"
  24 #include "missing_network.h"
  25 #include "netlink-util.h"
  26 #include "network-internal.h"
  27 #include "ordered-set.h"
  28 #include "parse-util.h"
  29 #include "random-util.h"
  30 #include "resolved-bus.h"
  31 #include "resolved-conf.h"
  32 #include "resolved-dns-stub.h"
  33 #include "resolved-dnssd.h"
  34 #include "resolved-etc-hosts.h"
  35 #include "resolved-llmnr.h"
  36 #include "resolved-manager.h"
  37 #include "resolved-mdns.h"
  38 #include "resolved-resolv-conf.h"
  39 #include "resolved-varlink.h"
  40 #include "socket-util.h"
  41 #include "string-table.h"
  42 #include "string-util.h"
  43 #include "utf8.h"
  44
  45 #define SEND_TIMEOUT_USEC (200 * USEC_PER_MSEC)
  46
  47 static int manager_process_link(sd_netlink *rtnl, sd_netlink_message *mm, void *userdata) {
  48         Manager *m = userdata;
  49         uint16_t type;
  50         Link *l;
  51         int ifindex, r;
  52
  53         assert(rtnl);
  54         assert(m);
  55         assert(mm);
  56
  57         r = sd_netlink_message_get_type(mm, &type);
  58         if (r < 0)
  59                 goto fail;
  60
  61         r = sd_rtnl_message_link_get_ifindex(mm, &ifindex);
  62         if (r < 0)
  63                 goto fail;
  64
  65         l = hashmap_get(m->links, INT_TO_PTR(ifindex));
  66
  67         switch (type) {
  68
  69         case RTM_NEWLINK:{
  70                 bool is_new = !l;
  71
  72                 if (!l) {
  73                         r = link_new(m, &l, ifindex);
  74                         if (r < 0)
  75                                 goto fail;
  76                 }
  77
  78                 r = link_process_rtnl(l, mm);
  79                 if (r < 0)
  80                         goto fail;
  81
  82                 r = link_update(l);
  83                 if (r < 0)
  84                         goto fail;
  85
  86                 if (is_new)
  87                         log_debug("Found new link %i/%s", ifindex, l->ifname);
  88
  89                 break;
  90         }
  91
  92         case RTM_DELLINK:
  93                 if (l) {
  94                         log_debug("Removing link %i/%s", l->ifindex, l->ifname);
  95                         link_remove_user(l);
  96                         link_free(l);
  97                 }
  98
  99                 break;
 100         }
 101
 102         return 0;
 103
 104 fail:
 105         log_warning_errno(r, "Failed to process RTNL link message: %m");
 106         return 0;
 107 }
 108
 109 static int manager_process_address(sd_netlink *rtnl, sd_netlink_message *mm, void *userdata) {
 110         Manager *m = userdata;
 111         union in_addr_union address;
 112         uint16_t type;
 113         int r, ifindex, family;
 114         LinkAddress *a;
 115         Link *l;
 116
 117         assert(rtnl);
 118         assert(mm);
 119         assert(m);
 120
 121         r = sd_netlink_message_get_type(mm, &type);
 122         if (r < 0)
 123                 goto fail;
 124
 125         r = sd_rtnl_message_addr_get_ifindex(mm, &ifindex);
 126         if (r < 0)
 127                 goto fail;
 128
 129         l = hashmap_get(m->links, INT_TO_PTR(ifindex));
 130         if (!l)
 131                 return 0;
 132
 133         r = sd_rtnl_message_addr_get_family(mm, &family);
 134         if (r < 0)
 135                 goto fail;
 136
 137         switch (family) {
 138
 139         case AF_INET:
 140                 r = sd_netlink_message_read_in_addr(mm, IFA_LOCAL, &address.in);
 141                 if (r < 0) {
 142                         r = sd_netlink_message_read_in_addr(mm, IFA_ADDRESS, &address.in);
 143                         if (r < 0)
 144                                 goto fail;
 145                 }
 146
 147                 break;
 148
 149         case AF_INET6:
 150                 r = sd_netlink_message_read_in6_addr(mm, IFA_LOCAL, &address.in6);
 151                 if (r < 0) {
 152                         r = sd_netlink_message_read_in6_addr(mm, IFA_ADDRESS, &address.in6);
 153                         if (r < 0)
 154                                 goto fail;
 155                 }
 156
 157                 break;
 158
 159         default:
 160                 return 0;
 161         }
 162
 163         a = link_find_address(l, family, &address);
 164
 165         switch (type) {
 166
 167         case RTM_NEWADDR:
 168
 169                 if (!a) {
 170                         r = link_address_new(l, &a, family, &address);
 171                         if (r < 0)
 172                                 return r;
 173                 }
 174
 175                 r = link_address_update_rtnl(a, mm);
 176                 if (r < 0)
 177                         return r;
 178
 179                 break;
 180
 181         case RTM_DELADDR:
 182                 link_address_free(a);
 183                 break;
 184         }
 185
 186         return 0;
 187
 188 fail:
 189         log_warning_errno(r, "Failed to process RTNL address message: %m");
 190         return 0;
 191 }
 192
 193 static int manager_rtnl_listen(Manager *m) {
 194         _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *req = NULL, *reply = NULL;
 195         sd_netlink_message *i;
 196         int r;
 197
 198         assert(m);
 199
 200         /* First, subscribe to interfaces coming and going */
 201         r = sd_netlink_open(&m->rtnl);
 202         if (r < 0)
 203                 return r;
 204
 205         r = sd_netlink_attach_event(m->rtnl, m->event, SD_EVENT_PRIORITY_IMPORTANT);
 206         if (r < 0)
 207                 return r;
 208
 209         r = sd_netlink_add_match(m->rtnl, NULL, RTM_NEWLINK, manager_process_link, NULL, m, "resolve-NEWLINK");
 210         if (r < 0)
 211                 return r;
 212
 213         r = sd_netlink_add_match(m->rtnl, NULL, RTM_DELLINK, manager_process_link, NULL, m, "resolve-DELLINK");
 214         if (r < 0)
 215                 return r;
 216
 217         r = sd_netlink_add_match(m->rtnl, NULL, RTM_NEWADDR, manager_process_address, NULL, m, "resolve-NEWADDR");
 218         if (r < 0)
 219                 return r;
 220
 221         r = sd_netlink_add_match(m->rtnl, NULL, RTM_DELADDR, manager_process_address, NULL, m, "resolve-DELADDR");
 222         if (r < 0)
 223                 return r;
 224
 225         /* Then, enumerate all links */
 226         r = sd_rtnl_message_new_link(m->rtnl, &req, RTM_GETLINK, 0);
 227         if (r < 0)
 228                 return r;
 229
 230         r = sd_netlink_message_request_dump(req, true);
 231         if (r < 0)
 232                 return r;
 233
 234         r = sd_netlink_call(m->rtnl, req, 0, &reply);
 235         if (r < 0)
 236                 return r;
 237
 238         for (i = reply; i; i = sd_netlink_message_next(i)) {
 239                 r = manager_process_link(m->rtnl, i, m);
 240                 if (r < 0)
 241                         return r;
 242         }
 243
 244         req = sd_netlink_message_unref(req);
 245         reply = sd_netlink_message_unref(reply);
 246
 247         /* Finally, enumerate all addresses, too */
 248         r = sd_rtnl_message_new_addr(m->rtnl, &req, RTM_GETADDR, 0, AF_UNSPEC);
 249         if (r < 0)
 250                 return r;
 251
 252         r = sd_netlink_message_request_dump(req, true);
 253         if (r < 0)
 254                 return r;
 255
 256         r = sd_netlink_call(m->rtnl, req, 0, &reply);
 257         if (r < 0)
 258                 return r;
 259
 260         for (i = reply; i; i = sd_netlink_message_next(i)) {
 261                 r = manager_process_address(m->rtnl, i, m);
 262                 if (r < 0)
 263                         return r;
 264         }
 265
 266         return r;
 267 }
 268
 269 static int on_network_event(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
 270         Manager *m = userdata;
 271         Link *l;
 272         int r;
 273
 274         assert(m);
 275
 276         sd_network_monitor_flush(m->network_monitor);
 277
 278         HASHMAP_FOREACH(l, m->links) {
 279                 r = link_update(l);
 280                 if (r < 0)
 281                         log_warning_errno(r, "Failed to update monitor information for %i: %m", l->ifindex);
 282         }
 283
 284         (void) manager_write_resolv_conf(m);
 285         (void) manager_send_changed(m, "DNS");
 286
 287         return 0;
 288 }
 289
 290 static int manager_network_monitor_listen(Manager *m) {
 291         int r, fd, events;
 292
 293         assert(m);
 294
 295         r = sd_network_monitor_new(&m->network_monitor, NULL);
 296         if (r < 0)
 297                 return r;
 298
 299         fd = sd_network_monitor_get_fd(m->network_monitor);
 300         if (fd < 0)
 301                 return fd;
 302
 303         events = sd_network_monitor_get_events(m->network_monitor);
 304         if (events < 0)
 305                 return events;
 306
 307         r = sd_event_add_io(m->event, &m->network_event_source, fd, events, &on_network_event, m);
 308         if (r < 0)
 309                 return r;
 310
 311         r = sd_event_source_set_priority(m->network_event_source, SD_EVENT_PRIORITY_IMPORTANT+5);
 312         if (r < 0)
 313                 return r;
 314
 315         (void) sd_event_source_set_description(m->network_event_source, "network-monitor");
 316
 317         return 0;
 318 }
 319
 320 static int determine_hostname(char **full_hostname, char **llmnr_hostname, char **mdns_hostname) {
 321         _cleanup_free_ char *h = NULL, *n = NULL;
 322 #if HAVE_LIBIDN2
 323         _cleanup_free_ char *utf8 = NULL;
 324 #elif HAVE_LIBIDN
 325         int k;
 326 #endif
 327         char label[DNS_LABEL_MAX];
 328         const char *p, *decoded;
 329         int r;
 330
 331         assert(full_hostname);
 332         assert(llmnr_hostname);
 333         assert(mdns_hostname);
 334
 335         /* Extract and normalize the first label of the locally configured hostname, and check it's not "localhost". */
 336
 337         r = gethostname_strict(&h);
 338         if (r < 0)
 339                 return log_debug_errno(r, "Can't determine system hostname: %m");
 340
 341         p = h;
 342         r = dns_label_unescape(&p, label, sizeof label, 0);
 343         if (r < 0)
 344                 return log_error_errno(r, "Failed to unescape hostname: %m");
 345         if (r == 0)
 346                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
 347                                        "Couldn't find a single label in hostname.");
 348
 349 #if HAVE_LIBIDN2
 350         r = idn2_to_unicode_8z8z(label, &utf8, 0);
 351         if (r != IDN2_OK)
 352                 return log_error("Failed to undo IDNA: %s", idn2_strerror(r));
 353         assert(utf8_is_valid(utf8));
 354
 355         r = strlen(utf8);
 356         decoded = utf8;
 357 #elif HAVE_LIBIDN
 358         k = dns_label_undo_idna(label, r, label, sizeof label);
 359         if (k < 0)
 360                 return log_error_errno(k, "Failed to undo IDNA: %m");
 361         if (k > 0)
 362                 r = k;
 363
 364         if (!utf8_is_valid(label))
 365                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
 366                                        "System hostname is not UTF-8 clean.");
 367         decoded = label;
 368 #else
 369         decoded = label; /* no decoding */
 370 #endif
 371
 372         r = dns_label_escape_new(decoded, r, &n);
 373         if (r < 0)
 374                 return log_error_errno(r, "Failed to escape hostname: %m");
 375
 376         if (is_localhost(n))
 377                 return log_debug_errno(SYNTHETIC_ERRNO(EINVAL),
 378                                        "System hostname is 'localhost', ignoring.");
 379
 380         r = dns_name_concat(n, "local", 0, mdns_hostname);
 381         if (r < 0)
 382                 return log_error_errno(r, "Failed to determine mDNS hostname: %m");
 383
 384         *llmnr_hostname = TAKE_PTR(n);
 385         *full_hostname = TAKE_PTR(h);
 386
 387         return 0;
 388 }
 389
 390 static const char *fallback_hostname(void) {
 391
 392         /* Determine the fall back hostname. For exposing this system to the outside world, we cannot have it to be
 393          * "localhost" even if that's the compiled in hostname. In this case, let's revert to "linux" instead. */
 394
 395         if (is_localhost(FALLBACK_HOSTNAME))
 396                 return "linux";
 397
 398         return FALLBACK_HOSTNAME;
 399 }
 400
 401 static int make_fallback_hostnames(char **full_hostname, char **llmnr_hostname, char **mdns_hostname) {
 402         _cleanup_free_ char *n = NULL, *m = NULL;
 403         char label[DNS_LABEL_MAX], *h;
 404         const char *p;
 405         int r;
 406
 407         assert(full_hostname);
 408         assert(llmnr_hostname);
 409         assert(mdns_hostname);
 410
 411         p = fallback_hostname();
 412         r = dns_label_unescape(&p, label, sizeof label, 0);
 413         if (r < 0)
 414                 return log_error_errno(r, "Failed to unescape fallback hostname: %m");
 415
 416         assert(r > 0); /* The fallback hostname must have at least one label */
 417
 418         r = dns_label_escape_new(label, r, &n);
 419         if (r < 0)
 420                 return log_error_errno(r, "Failed to escape fallback hostname: %m");
 421
 422         r = dns_name_concat(n, "local", 0, &m);
 423         if (r < 0)
 424                 return log_error_errno(r, "Failed to concatenate mDNS hostname: %m");
 425
 426         h = strdup(fallback_hostname());
 427         if (!h)
 428                 return log_oom();
 429
 430         *llmnr_hostname = TAKE_PTR(n);
 431         *mdns_hostname = TAKE_PTR(m);
 432
 433         *full_hostname = h;
 434
 435         return 0;
 436 }
 437
 438 static int on_hostname_change(sd_event_source *es, int fd, uint32_t revents, void *userdata) {
 439         _cleanup_free_ char *full_hostname = NULL, *llmnr_hostname = NULL, *mdns_hostname = NULL;
 440         Manager *m = userdata;
 441         bool llmnr_hostname_changed;
 442         int r;
 443
 444         assert(m);
 445
 446         r = determine_hostname(&full_hostname, &llmnr_hostname, &mdns_hostname);
 447         if (r < 0)
 448                 return 0; /* ignore invalid hostnames */
 449
 450         llmnr_hostname_changed = !streq(llmnr_hostname, m->llmnr_hostname);
 451         if (streq(full_hostname, m->full_hostname) &&
 452             !llmnr_hostname_changed &&
 453             streq(mdns_hostname, m->mdns_hostname))
 454                 return 0;
 455
 456         log_info("System hostname changed to '%s'.", full_hostname);
 457
 458         free_and_replace(m->full_hostname, full_hostname);
 459         free_and_replace(m->llmnr_hostname, llmnr_hostname);
 460         free_and_replace(m->mdns_hostname, mdns_hostname);
 461
 462         manager_refresh_rrs(m);
 463         (void) manager_send_changed(m, "LLMNRHostname");
 464
 465         return 0;
 466 }
 467
 468 static int manager_watch_hostname(Manager *m) {
 469         int r;
 470
 471         assert(m);
 472
 473         m->hostname_fd = open("/proc/sys/kernel/hostname",
 474                               O_RDONLY|O_CLOEXEC|O_NONBLOCK|O_NOCTTY);
 475         if (m->hostname_fd < 0) {
 476                 log_warning_errno(errno, "Failed to watch hostname: %m");
 477                 return 0;
 478         }
 479
 480         r = sd_event_add_io(m->event, &m->hostname_event_source, m->hostname_fd, 0, on_hostname_change, m);
 481         if (r < 0) {
 482                 if (r == -EPERM)
 483                         /* kernels prior to 3.2 don't support polling this file. Ignore the failure. */
 484                         m->hostname_fd = safe_close(m->hostname_fd);
 485                 else
 486                         return log_error_errno(r, "Failed to add hostname event source: %m");
 487         }
 488
 489         (void) sd_event_source_set_description(m->hostname_event_source, "hostname");
 490
 491         r = determine_hostname(&m->full_hostname, &m->llmnr_hostname, &m->mdns_hostname);
 492         if (r < 0) {
 493                 log_info("Defaulting to hostname '%s'.", fallback_hostname());
 494
 495                 r = make_fallback_hostnames(&m->full_hostname, &m->llmnr_hostname, &m->mdns_hostname);
 496                 if (r < 0)
 497                         return r;
 498         } else
 499                 log_info("Using system hostname '%s'.", m->full_hostname);
 500
 501         return 0;
 502 }
 503
 504 static int manager_sigusr1(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {
 505         _cleanup_free_ char *buffer = NULL;
 506         _cleanup_fclose_ FILE *f = NULL;
 507         Manager *m = userdata;
 508         DnsServer *server;
 509         size_t size = 0;
 510         DnsScope *scope;
 511         Link *l;
 512
 513         assert(s);
 514         assert(si);
 515         assert(m);
 516
 517         f = open_memstream_unlocked(&buffer, &size);
 518         if (!f)
 519                 return log_oom();
 520
 521         LIST_FOREACH(scopes, scope, m->dns_scopes)
 522                 dns_scope_dump(scope, f);
 523
 524         LIST_FOREACH(servers, server, m->dns_servers)
 525                 dns_server_dump(server, f);
 526         LIST_FOREACH(servers, server, m->fallback_dns_servers)
 527                 dns_server_dump(server, f);
 528         HASHMAP_FOREACH(l, m->links)
 529                 LIST_FOREACH(servers, server, l->dns_servers)
 530                         dns_server_dump(server, f);
 531
 532         if (fflush_and_check(f) < 0)
 533                 return log_oom();
 534
 535         log_dump(LOG_INFO, buffer);
 536         return 0;
 537 }
 538
 539 static int manager_sigusr2(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {
 540         Manager *m = userdata;
 541
 542         assert(s);
 543         assert(si);
 544         assert(m);
 545
 546         manager_flush_caches(m);
 547
 548         return 0;
 549 }
 550
 551 static int manager_sigrtmin1(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {
 552         Manager *m = userdata;
 553
 554         assert(s);
 555         assert(si);
 556         assert(m);
 557
 558         manager_reset_server_features(m);
 559         return 0;
 560 }
 561
 562 int manager_new(Manager **ret) {
 563         _cleanup_(manager_freep) Manager *m = NULL;
 564         int r;
 565
 566         assert(ret);
 567
 568         m = new(Manager, 1);
 569         if (!m)
 570                 return -ENOMEM;
 571
 572         *m = (Manager) {
 573                 .llmnr_ipv4_udp_fd = -1,
 574                 .llmnr_ipv6_udp_fd = -1,
 575                 .llmnr_ipv4_tcp_fd = -1,
 576                 .llmnr_ipv6_tcp_fd = -1,
 577                 .mdns_ipv4_fd = -1,
 578                 .mdns_ipv6_fd = -1,
 579                 .hostname_fd = -1,
 580
 581                 .llmnr_support = DEFAULT_LLMNR_MODE,
 582                 .mdns_support = DEFAULT_MDNS_MODE,
 583                 .dnssec_mode = DEFAULT_DNSSEC_MODE,
 584                 .dns_over_tls_mode = DEFAULT_DNS_OVER_TLS_MODE,
 585                 .enable_cache = DNS_CACHE_MODE_YES,
 586                 .dns_stub_listener_mode = DNS_STUB_LISTENER_YES,
 587                 .read_resolv_conf = true,
 588                 .need_builtin_fallbacks = true,
 589                 .etc_hosts_last = USEC_INFINITY,
 590                 .etc_hosts_mtime = USEC_INFINITY,
 591                 .etc_hosts_ino = 0,
 592                 .etc_hosts_dev = 0,
 593                 .read_etc_hosts = true,
 594         };
 595
 596         r = dns_trust_anchor_load(&m->trust_anchor);
 597         if (r < 0)
 598                 return r;
 599
 600         r = manager_parse_config_file(m);
 601         if (r < 0)
 602                 log_warning_errno(r, "Failed to parse configuration file: %m");
 603
 604 #if ENABLE_DNS_OVER_TLS
 605         r = dnstls_manager_init(m);
 606         if (r < 0)
 607                 return r;
 608 #endif
 609
 610         r = sd_event_default(&m->event);
 611         if (r < 0)
 612                 return r;
 613
 614         (void) sd_event_add_signal(m->event, NULL, SIGTERM, NULL,  NULL);
 615         (void) sd_event_add_signal(m->event, NULL, SIGINT, NULL, NULL);
 616
 617         (void) sd_event_set_watchdog(m->event, true);
 618
 619         r = manager_watch_hostname(m);
 620         if (r < 0)
 621                 return r;
 622
 623         r = dnssd_load(m);
 624         if (r < 0)
 625                 log_warning_errno(r, "Failed to load DNS-SD configuration files: %m");
 626
 627         r = dns_scope_new(m, &m->unicast_scope, NULL, DNS_PROTOCOL_DNS, AF_UNSPEC);
 628         if (r < 0)
 629                 return r;
 630
 631         r = manager_network_monitor_listen(m);
 632         if (r < 0)
 633                 return r;
 634
 635         r = manager_rtnl_listen(m);
 636         if (r < 0)
 637                 return r;
 638
 639         r = manager_connect_bus(m);
 640         if (r < 0)
 641                 return r;
 642
 643         (void) sd_event_add_signal(m->event, &m->sigusr1_event_source, SIGUSR1, manager_sigusr1, m);
 644         (void) sd_event_add_signal(m->event, &m->sigusr2_event_source, SIGUSR2, manager_sigusr2, m);
 645         (void) sd_event_add_signal(m->event, &m->sigrtmin1_event_source, SIGRTMIN+1, manager_sigrtmin1, m);
 646
 647         manager_cleanup_saved_user(m);
 648
 649         *ret = TAKE_PTR(m);
 650
 651         return 0;
 652 }
 653
 654 int manager_start(Manager *m) {
 655         int r;
 656
 657         assert(m);
 658
 659         r = manager_dns_stub_start(m);
 660         if (r < 0)
 661                 return r;
 662
 663         r = manager_varlink_init(m);
 664         if (r < 0)
 665                 return r;
 666
 667         return 0;
 668 }
 669
 670 Manager *manager_free(Manager *m) {
 671         Link *l;
 672         DnssdService *s;
 673
 674         if (!m)
 675                 return NULL;
 676
 677         dns_server_unlink_all(m->dns_servers);
 678         dns_server_unlink_all(m->fallback_dns_servers);
 679         dns_search_domain_unlink_all(m->search_domains);
 680
 681         while ((l = hashmap_first(m->links)))
 682                link_free(l);
 683
 684         while (m->dns_queries)
 685                 dns_query_free(m->dns_queries);
 686
 687         dns_scope_free(m->unicast_scope);
 688
 689         /* At this point only orphaned streams should remain. All others should have been freed already by their
 690          * owners */
 691         while (m->dns_streams)
 692                 dns_stream_unref(m->dns_streams);
 693
 694 #if ENABLE_DNS_OVER_TLS
 695         dnstls_manager_free(m);
 696 #endif
 697
 698         hashmap_free(m->links);
 699         hashmap_free(m->dns_transactions);
 700
 701         sd_event_source_unref(m->network_event_source);
 702         sd_network_monitor_unref(m->network_monitor);
 703
 704         sd_netlink_unref(m->rtnl);
 705         sd_event_source_unref(m->rtnl_event_source);
 706
 707         manager_llmnr_stop(m);
 708         manager_mdns_stop(m);
 709         manager_dns_stub_stop(m);
 710         manager_varlink_done(m);
 711
 712         ordered_set_free(m->dns_extra_stub_listeners);
 713
 714         bus_verify_polkit_async_registry_free(m->polkit_registry);
 715
 716         sd_bus_flush_close_unref(m->bus);
 717
 718         sd_event_source_unref(m->sigusr1_event_source);
 719         sd_event_source_unref(m->sigusr2_event_source);
 720         sd_event_source_unref(m->sigrtmin1_event_source);
 721
 722         sd_event_unref(m->event);
 723
 724         dns_resource_key_unref(m->llmnr_host_ipv4_key);
 725         dns_resource_key_unref(m->llmnr_host_ipv6_key);
 726         dns_resource_key_unref(m->mdns_host_ipv4_key);
 727         dns_resource_key_unref(m->mdns_host_ipv6_key);
 728
 729         sd_event_source_unref(m->hostname_event_source);
 730         safe_close(m->hostname_fd);
 731
 732         free(m->full_hostname);
 733         free(m->llmnr_hostname);
 734         free(m->mdns_hostname);
 735
 736         while ((s = hashmap_first(m->dnssd_services)))
 737                dnssd_service_free(s);
 738         hashmap_free(m->dnssd_services);
 739
 740         dns_trust_anchor_flush(&m->trust_anchor);
 741         manager_etc_hosts_flush(m);
 742
 743         return mfree(m);
 744 }
 745
 746 int manager_recv(Manager *m, int fd, DnsProtocol protocol, DnsPacket **ret) {
 747         _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;
 748         CMSG_BUFFER_TYPE(CMSG_SPACE(MAXSIZE(struct in_pktinfo, struct in6_pktinfo))
 749                          + CMSG_SPACE(int) /* ttl/hoplimit */
 750                          + EXTRA_CMSG_SPACE /* kernel appears to require extra buffer space */) control;
 751         union sockaddr_union sa;
 752         struct iovec iov;
 753         struct msghdr mh = {
 754                 .msg_name = &sa.sa,
 755                 .msg_namelen = sizeof(sa),
 756                 .msg_iov = &iov,
 757                 .msg_iovlen = 1,
 758                 .msg_control = &control,
 759                 .msg_controllen = sizeof(control),
 760         };
 761         struct cmsghdr *cmsg;
 762         ssize_t ms, l;
 763         int r;
 764
 765         assert(m);
 766         assert(fd >= 0);
 767         assert(ret);
 768
 769         ms = next_datagram_size_fd(fd);
 770         if (ms < 0)
 771                 return ms;
 772
 773         r = dns_packet_new(&p, protocol, ms, DNS_PACKET_SIZE_MAX);
 774         if (r < 0)
 775                 return r;
 776
 777         iov = IOVEC_MAKE(DNS_PACKET_DATA(p), p->allocated);
 778
 779         l = recvmsg_safe(fd, &mh, 0);
 780         if (IN_SET(l, -EAGAIN, -EINTR))
 781                 return 0;
 782         if (l < 0)
 783                 return l;
 784         if (l == 0)
 785                 return 0;
 786
 787         assert(!(mh.msg_flags & MSG_TRUNC));
 788
 789         p->size = (size_t) l;
 790
 791         p->family = sa.sa.sa_family;
 792         p->ipproto = IPPROTO_UDP;
 793         if (p->family == AF_INET) {
 794                 p->sender.in = sa.in.sin_addr;
 795                 p->sender_port = be16toh(sa.in.sin_port);
 796         } else if (p->family == AF_INET6) {
 797                 p->sender.in6 = sa.in6.sin6_addr;
 798                 p->sender_port = be16toh(sa.in6.sin6_port);
 799                 p->ifindex = sa.in6.sin6_scope_id;
 800         } else
 801                 return -EAFNOSUPPORT;
 802
 803         CMSG_FOREACH(cmsg, &mh) {
 804
 805                 if (cmsg->cmsg_level == IPPROTO_IPV6) {
 806                         assert(p->family == AF_INET6);
 807
 808                         switch (cmsg->cmsg_type) {
 809
 810                         case IPV6_PKTINFO: {
 811                                 struct in6_pktinfo *i = (struct in6_pktinfo*) CMSG_DATA(cmsg);
 812
 813                                 if (p->ifindex <= 0)
 814                                         p->ifindex = i->ipi6_ifindex;
 815
 816                                 p->destination.in6 = i->ipi6_addr;
 817                                 break;
 818                         }
 819
 820                         case IPV6_HOPLIMIT:
 821                                 p->ttl = *(int *) CMSG_DATA(cmsg);
 822                                 break;
 823
 824                         }
 825                 } else if (cmsg->cmsg_level == IPPROTO_IP) {
 826                         assert(p->family == AF_INET);
 827
 828                         switch (cmsg->cmsg_type) {
 829
 830                         case IP_PKTINFO: {
 831                                 struct in_pktinfo *i = (struct in_pktinfo*) CMSG_DATA(cmsg);
 832
 833                                 if (p->ifindex <= 0)
 834                                         p->ifindex = i->ipi_ifindex;
 835
 836                                 p->destination.in = i->ipi_addr;
 837                                 break;
 838                         }
 839
 840                         case IP_TTL:
 841                                 p->ttl = *(int *) CMSG_DATA(cmsg);
 842                                 break;
 843                         }
 844                 }
 845         }
 846
 847         /* The Linux kernel sets the interface index to the loopback
 848          * device if the packet came from the local host since it
 849          * avoids the routing table in such a case. Let's unset the
 850          * interface index in such a case. */
 851         if (p->ifindex == LOOPBACK_IFINDEX)
 852                 p->ifindex = 0;
 853
 854         if (protocol != DNS_PROTOCOL_DNS) {
 855                 /* If we don't know the interface index still, we look for the
 856                  * first local interface with a matching address. Yuck! */
 857                 if (p->ifindex <= 0)
 858                         p->ifindex = manager_find_ifindex(m, p->family, &p->destination);
 859         }
 860
 861         *ret = TAKE_PTR(p);
 862
 863         return 1;
 864 }
 865
 866 static int sendmsg_loop(int fd, struct msghdr *mh, int flags) {
 867         int r;
 868
 869         assert(fd >= 0);
 870         assert(mh);
 871
 872         for (;;) {
 873                 if (sendmsg(fd, mh, flags) >= 0)
 874                         return 0;
 875
 876                 if (errno == EINTR)
 877                         continue;
 878
 879                 if (errno != EAGAIN)
 880                         return -errno;
 881
 882                 r = fd_wait_for_event(fd, POLLOUT, SEND_TIMEOUT_USEC);
 883                 if (r < 0)
 884                         return r;
 885                 if (r == 0)
 886                         return -ETIMEDOUT;
 887         }
 888 }
 889
 890 static int write_loop(int fd, void *message, size_t length) {
 891         int r;
 892
 893         assert(fd >= 0);
 894         assert(message);
 895
 896         for (;;) {
 897                 if (write(fd, message, length) >= 0)
 898                         return 0;
 899
 900                 if (errno == EINTR)
 901                         continue;
 902
 903                 if (errno != EAGAIN)
 904                         return -errno;
 905
 906                 r = fd_wait_for_event(fd, POLLOUT, SEND_TIMEOUT_USEC);
 907                 if (r < 0)
 908                         return r;
 909                 if (r == 0)
 910                         return -ETIMEDOUT;
 911         }
 912 }
 913
 914 int manager_write(Manager *m, int fd, DnsPacket *p) {
 915         int r;
 916
 917         log_debug("Sending %s packet with id %" PRIu16 ".", DNS_PACKET_QR(p) ? "response" : "query", DNS_PACKET_ID(p));
 918
 919         r = write_loop(fd, DNS_PACKET_DATA(p), p->size);
 920         if (r < 0)
 921                 return r;
 922
 923         return 0;
 924 }
 925
 926 static int manager_ipv4_send(
 927                 Manager *m,
 928                 int fd,
 929                 int ifindex,
 930                 const struct in_addr *destination,
 931                 uint16_t port,
 932                 const struct in_addr *source,
 933                 DnsPacket *p) {
 934
 935         CMSG_BUFFER_TYPE(CMSG_SPACE(sizeof(struct in_pktinfo))) control = {};
 936         union sockaddr_union sa;
 937         struct iovec iov;
 938         struct msghdr mh = {
 939                 .msg_iov = &iov,
 940                 .msg_iovlen = 1,
 941                 .msg_name = &sa.sa,
 942                 .msg_namelen = sizeof(sa.in),
 943         };
 944
 945         assert(m);
 946         assert(fd >= 0);
 947         assert(destination);
 948         assert(port > 0);
 949         assert(p);
 950
 951         iov = IOVEC_MAKE(DNS_PACKET_DATA(p), p->size);
 952
 953         sa = (union sockaddr_union) {
 954                 .in.sin_family = AF_INET,
 955                 .in.sin_addr = *destination,
 956                 .in.sin_port = htobe16(port),
 957         };
 958
 959         if (ifindex > 0) {
 960                 struct cmsghdr *cmsg;
 961                 struct in_pktinfo *pi;
 962
 963                 mh.msg_control = &control;
 964                 mh.msg_controllen = sizeof(control);
 965
 966                 cmsg = CMSG_FIRSTHDR(&mh);
 967                 cmsg->cmsg_len = CMSG_LEN(sizeof(struct in_pktinfo));
 968                 cmsg->cmsg_level = IPPROTO_IP;
 969                 cmsg->cmsg_type = IP_PKTINFO;
 970
 971                 pi = (struct in_pktinfo*) CMSG_DATA(cmsg);
 972                 pi->ipi_ifindex = ifindex;
 973
 974                 if (source)
 975                         pi->ipi_spec_dst = *source;
 976         }
 977
 978         return sendmsg_loop(fd, &mh, 0);
 979 }
 980
 981 static int manager_ipv6_send(
 982                 Manager *m,
 983                 int fd,
 984                 int ifindex,
 985                 const struct in6_addr *destination,
 986                 uint16_t port,
 987                 const struct in6_addr *source,
 988                 DnsPacket *p) {
 989
 990         CMSG_BUFFER_TYPE(CMSG_SPACE(sizeof(struct in6_pktinfo))) control = {};
 991         union sockaddr_union sa;
 992         struct iovec iov;
 993         struct msghdr mh = {
 994                 .msg_iov = &iov,
 995                 .msg_iovlen = 1,
 996                 .msg_name = &sa.sa,
 997                 .msg_namelen = sizeof(sa.in6),
 998         };
 999
1000         assert(m);
1001         assert(fd >= 0);
1002         assert(destination);
1003         assert(port > 0);
1004         assert(p);
1005
1006         iov = IOVEC_MAKE(DNS_PACKET_DATA(p), p->size);
1007
1008         sa = (union sockaddr_union) {
1009                 .in6.sin6_family = AF_INET6,
1010                 .in6.sin6_addr = *destination,
1011                 .in6.sin6_port = htobe16(port),
1012                 .in6.sin6_scope_id = ifindex,
1013         };
1014
1015         if (ifindex > 0) {
1016                 struct cmsghdr *cmsg;
1017                 struct in6_pktinfo *pi;
1018
1019                 mh.msg_control = &control;
1020                 mh.msg_controllen = sizeof(control);
1021
1022                 cmsg = CMSG_FIRSTHDR(&mh);
1023                 cmsg->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo));
1024                 cmsg->cmsg_level = IPPROTO_IPV6;
1025                 cmsg->cmsg_type = IPV6_PKTINFO;
1026
1027                 pi = (struct in6_pktinfo*) CMSG_DATA(cmsg);
1028                 pi->ipi6_ifindex = ifindex;
1029
1030                 if (source)
1031                         pi->ipi6_addr = *source;
1032         }
1033
1034         return sendmsg_loop(fd, &mh, 0);
1035 }
1036
1037 int manager_send(
1038                 Manager *m,
1039                 int fd,
1040                 int ifindex,
1041                 int family,
1042                 const union in_addr_union *destination,
1043                 uint16_t port,
1044                 const union in_addr_union *source,
1045                 DnsPacket *p) {
1046
1047         assert(m);
1048         assert(fd >= 0);
1049         assert(destination);
1050         assert(port > 0);
1051         assert(p);
1052
1053         log_debug("Sending %s packet with id %" PRIu16 " on interface %i/%s.", DNS_PACKET_QR(p) ? "response" : "query", DNS_PACKET_ID(p), ifindex, af_to_name(family));
1054
1055         if (family == AF_INET)
1056                 return manager_ipv4_send(m, fd, ifindex, &destination->in, port, source ? &source->in : NULL, p);
1057         if (family == AF_INET6)
1058                 return manager_ipv6_send(m, fd, ifindex, &destination->in6, port, source ? &source->in6 : NULL, p);
1059
1060         return -EAFNOSUPPORT;
1061 }
1062
1063 uint32_t manager_find_mtu(Manager *m) {
1064         uint32_t mtu = 0;
1065         Link *l;
1066
1067         /* If we don't know on which link a DNS packet would be
1068          * delivered, let's find the largest MTU that works on all
1069          * interfaces we know of */
1070
1071         HASHMAP_FOREACH(l, m->links) {
1072                 if (l->mtu <= 0)
1073                         continue;
1074
1075                 if (mtu <= 0 || l->mtu < mtu)
1076                         mtu = l->mtu;
1077         }
1078
1079         return mtu;
1080 }
1081
1082 int manager_find_ifindex(Manager *m, int family, const union in_addr_union *in_addr) {
1083         LinkAddress *a;
1084
1085         assert(m);
1086
1087         a = manager_find_link_address(m, family, in_addr);
1088         if (a)
1089                 return a->link->ifindex;
1090
1091         return 0;
1092 }
1093
1094 void manager_refresh_rrs(Manager *m) {
1095         Link *l;
1096         DnssdService *s;
1097
1098         assert(m);
1099
1100         m->llmnr_host_ipv4_key = dns_resource_key_unref(m->llmnr_host_ipv4_key);
1101         m->llmnr_host_ipv6_key = dns_resource_key_unref(m->llmnr_host_ipv6_key);
1102         m->mdns_host_ipv4_key = dns_resource_key_unref(m->mdns_host_ipv4_key);
1103         m->mdns_host_ipv6_key = dns_resource_key_unref(m->mdns_host_ipv6_key);
1104
1105         if (m->mdns_support == RESOLVE_SUPPORT_YES)
1106                 HASHMAP_FOREACH(s, m->dnssd_services)
1107                         if (dnssd_update_rrs(s) < 0)
1108                                 log_warning("Failed to refresh DNS-SD service '%s'", s->name);
1109
1110         HASHMAP_FOREACH(l, m->links) {
1111                 link_add_rrs(l, true);
1112                 link_add_rrs(l, false);
1113         }
1114 }
1115
1116 static int manager_next_random_name(const char *old, char **ret_new) {
1117         const char *p;
1118         uint64_t u, a;
1119         char *n;
1120
1121         p = strchr(old, 0);
1122         assert(p);
1123
1124         while (p > old) {
1125                 if (!strchr(DIGITS, p[-1]))
1126                         break;
1127
1128                 p--;
1129         }
1130
1131         if (*p == 0 || safe_atou64(p, &u) < 0 || u <= 0)
1132                 u = 1;
1133
1134         /* Add a random number to the old value. This way we can avoid
1135          * that two hosts pick the same hostname, win on IPv4 and lose
1136          * on IPv6 (or vice versa), and pick the same hostname
1137          * replacement hostname, ad infinitum. We still want the
1138          * numbers to go up monotonically, hence we just add a random
1139          * value 1..10 */
1140
1141         random_bytes(&a, sizeof(a));
1142         u += 1 + a % 10;
1143
1144         if (asprintf(&n, "%.*s%" PRIu64, (int) (p - old), old, u) < 0)
1145                 return -ENOMEM;
1146
1147         *ret_new = n;
1148
1149         return 0;
1150 }
1151
1152 int manager_next_hostname(Manager *m) {
1153         _cleanup_free_ char *h = NULL, *k = NULL;
1154         int r;
1155
1156         assert(m);
1157
1158         r = manager_next_random_name(m->llmnr_hostname, &h);
1159         if (r < 0)
1160                 return r;
1161
1162         r = dns_name_concat(h, "local", 0, &k);
1163         if (r < 0)
1164                 return r;
1165
1166         log_info("Hostname conflict, changing published hostname from '%s' to '%s'.", m->llmnr_hostname, h);
1167
1168         free_and_replace(m->llmnr_hostname, h);
1169         free_and_replace(m->mdns_hostname, k);
1170
1171         manager_refresh_rrs(m);
1172         (void) manager_send_changed(m, "LLMNRHostname");
1173
1174         return 0;
1175 }
1176
1177 LinkAddress* manager_find_link_address(Manager *m, int family, const union in_addr_union *in_addr) {
1178         Link *l;
1179
1180         assert(m);
1181
1182         HASHMAP_FOREACH(l, m->links) {
1183                 LinkAddress *a;
1184
1185                 a = link_find_address(l, family, in_addr);
1186                 if (a)
1187                         return a;
1188         }
1189
1190         return NULL;
1191 }
1192
1193 bool manager_our_packet(Manager *m, DnsPacket *p) {
1194         assert(m);
1195         assert(p);
1196
1197         return !!manager_find_link_address(m, p->family, &p->sender);
1198 }
1199
1200 DnsScope* manager_find_scope(Manager *m, DnsPacket *p) {
1201         Link *l;
1202
1203         assert(m);
1204         assert(p);
1205
1206         l = hashmap_get(m->links, INT_TO_PTR(p->ifindex));
1207         if (!l)
1208                 return NULL;
1209
1210         switch (p->protocol) {
1211         case DNS_PROTOCOL_LLMNR:
1212                 if (p->family == AF_INET)
1213                         return l->llmnr_ipv4_scope;
1214                 else if (p->family == AF_INET6)
1215                         return l->llmnr_ipv6_scope;
1216
1217                 break;
1218
1219         case DNS_PROTOCOL_MDNS:
1220                 if (p->family == AF_INET)
1221                         return l->mdns_ipv4_scope;
1222                 else if (p->family == AF_INET6)
1223                         return l->mdns_ipv6_scope;
1224
1225                 break;
1226
1227         default:
1228                 break;
1229         }
1230
1231         return NULL;
1232 }
1233
1234 void manager_verify_all(Manager *m) {
1235         DnsScope *s;
1236
1237         assert(m);
1238
1239         LIST_FOREACH(scopes, s, m->dns_scopes)
1240                 dns_zone_verify_all(&s->zone);
1241 }
1242
1243 int manager_is_own_hostname(Manager *m, const char *name) {
1244         int r;
1245
1246         assert(m);
1247         assert(name);
1248
1249         if (m->llmnr_hostname) {
1250                 r = dns_name_equal(name, m->llmnr_hostname);
1251                 if (r != 0)
1252                         return r;
1253         }
1254
1255         if (m->mdns_hostname) {
1256                 r = dns_name_equal(name, m->mdns_hostname);
1257                 if (r != 0)
1258                         return r;
1259         }
1260
1261         if (m->full_hostname)
1262                 return dns_name_equal(name, m->full_hostname);
1263
1264         return 0;
1265 }
1266
1267 int manager_compile_dns_servers(Manager *m, OrderedSet **dns) {
1268         DnsServer *s;
1269         Link *l;
1270         int r;
1271
1272         assert(m);
1273         assert(dns);
1274
1275         r = ordered_set_ensure_allocated(dns, &dns_server_hash_ops);
1276         if (r < 0)
1277                 return r;
1278
1279         /* First add the system-wide servers and domains */
1280         LIST_FOREACH(servers, s, m->dns_servers) {
1281                 r = ordered_set_put(*dns, s);
1282                 if (r == -EEXIST)
1283                         continue;
1284                 if (r < 0)
1285                         return r;
1286         }
1287
1288         /* Then, add the per-link servers */
1289         HASHMAP_FOREACH(l, m->links) {
1290                 LIST_FOREACH(servers, s, l->dns_servers) {
1291                         r = ordered_set_put(*dns, s);
1292                         if (r == -EEXIST)
1293                                 continue;
1294                         if (r < 0)
1295                                 return r;
1296                 }
1297         }
1298
1299         /* If we found nothing, add the fallback servers */
1300         if (ordered_set_isempty(*dns)) {
1301                 LIST_FOREACH(servers, s, m->fallback_dns_servers) {
1302                         r = ordered_set_put(*dns, s);
1303                         if (r == -EEXIST)
1304                                 continue;
1305                         if (r < 0)
1306                                 return r;
1307                 }
1308         }
1309
1310         return 0;
1311 }
1312
1313 /* filter_route is a tri-state:
1314  *   < 0: no filtering
1315  *   = 0 or false: return only domains which should be used for searching
1316  *   > 0 or true: return only domains which are for routing only
1317  */
1318 int manager_compile_search_domains(Manager *m, OrderedSet **domains, int filter_route) {
1319         DnsSearchDomain *d;
1320         Link *l;
1321         int r;
1322
1323         assert(m);
1324         assert(domains);
1325
1326         r = ordered_set_ensure_allocated(domains, &dns_name_hash_ops);
1327         if (r < 0)
1328                 return r;
1329
1330         LIST_FOREACH(domains, d, m->search_domains) {
1331
1332                 if (filter_route >= 0 &&
1333                     d->route_only != !!filter_route)
1334                         continue;
1335
1336                 r = ordered_set_put(*domains, d->name);
1337                 if (r == -EEXIST)
1338                         continue;
1339                 if (r < 0)
1340                         return r;
1341         }
1342
1343         HASHMAP_FOREACH(l, m->links) {
1344
1345                 LIST_FOREACH(domains, d, l->search_domains) {
1346
1347                         if (filter_route >= 0 &&
1348                             d->route_only != !!filter_route)
1349                                 continue;
1350
1351                         r = ordered_set_put(*domains, d->name);
1352                         if (r == -EEXIST)
1353                                 continue;
1354                         if (r < 0)
1355                                 return r;
1356                 }
1357         }
1358
1359         return 0;
1360 }
1361
1362 DnssecMode manager_get_dnssec_mode(Manager *m) {
1363         assert(m);
1364
1365         if (m->dnssec_mode != _DNSSEC_MODE_INVALID)
1366                 return m->dnssec_mode;
1367
1368         return DNSSEC_NO;
1369 }
1370
1371 bool manager_dnssec_supported(Manager *m) {
1372         DnsServer *server;
1373         Link *l;
1374
1375         assert(m);
1376
1377         if (manager_get_dnssec_mode(m) == DNSSEC_NO)
1378                 return false;
1379
1380         server = manager_get_dns_server(m);
1381         if (server && !dns_server_dnssec_supported(server))
1382                 return false;
1383
1384         HASHMAP_FOREACH(l, m->links)
1385                 if (!link_dnssec_supported(l))
1386                         return false;
1387
1388         return true;
1389 }
1390
1391 DnsOverTlsMode manager_get_dns_over_tls_mode(Manager *m) {
1392         assert(m);
1393
1394         if (m->dns_over_tls_mode != _DNS_OVER_TLS_MODE_INVALID)
1395                 return m->dns_over_tls_mode;
1396
1397         return DNS_OVER_TLS_NO;
1398 }
1399
1400 void manager_dnssec_verdict(Manager *m, DnssecVerdict verdict, const DnsResourceKey *key) {
1401
1402         assert(verdict >= 0);
1403         assert(verdict < _DNSSEC_VERDICT_MAX);
1404
1405         if (DEBUG_LOGGING) {
1406                 char s[DNS_RESOURCE_KEY_STRING_MAX];
1407
1408                 log_debug("Found verdict for lookup %s: %s",
1409                           dns_resource_key_to_string(key, s, sizeof s),
1410                           dnssec_verdict_to_string(verdict));
1411         }
1412
1413         m->n_dnssec_verdict[verdict]++;
1414 }
1415
1416 bool manager_routable(Manager *m, int family) {
1417         Link *l;
1418
1419         assert(m);
1420
1421         /* Returns true if the host has at least one interface with a routable address of the specified type */
1422
1423         HASHMAP_FOREACH(l, m->links)
1424                 if (link_relevant(l, family, false))
1425                         return true;
1426
1427         return false;
1428 }
1429
1430 void manager_flush_caches(Manager *m) {
1431         DnsScope *scope;
1432
1433         assert(m);
1434
1435         LIST_FOREACH(scopes, scope, m->dns_scopes)
1436                 dns_cache_flush(&scope->cache);
1437
1438         log_info("Flushed all caches.");
1439 }
1440
1441 void manager_reset_server_features(Manager *m) {
1442         Link *l;
1443
1444         dns_server_reset_features_all(m->dns_servers);
1445         dns_server_reset_features_all(m->fallback_dns_servers);
1446
1447         HASHMAP_FOREACH(l, m->links)
1448                 dns_server_reset_features_all(l->dns_servers);
1449
1450         log_info("Resetting learnt feature levels on all servers.");
1451 }
1452
1453 void manager_cleanup_saved_user(Manager *m) {
1454         _cleanup_closedir_ DIR *d = NULL;
1455         struct dirent *de;
1456
1457         assert(m);
1458
1459         /* Clean up all saved per-link files in /run/systemd/resolve/netif/ that don't have a matching interface
1460          * anymore. These files are created to persist settings pushed in by the user via the bus, so that resolved can
1461          * be restarted without losing this data. */
1462
1463         d = opendir("/run/systemd/resolve/netif/");
1464         if (!d) {
1465                 if (errno == ENOENT)
1466                         return;
1467
1468                 log_warning_errno(errno, "Failed to open interface directory: %m");
1469                 return;
1470         }
1471
1472         FOREACH_DIRENT_ALL(de, d, log_error_errno(errno, "Failed to read interface directory: %m")) {
1473                 _cleanup_free_ char *p = NULL;
1474                 int ifindex;
1475                 Link *l;
1476
1477                 if (!IN_SET(de->d_type, DT_UNKNOWN, DT_REG))
1478                         continue;
1479
1480                 if (dot_or_dot_dot(de->d_name))
1481                         continue;
1482
1483                 ifindex = parse_ifindex(de->d_name);
1484                 if (ifindex < 0) /* Probably some temporary file from a previous run. Delete it */
1485                         goto rm;
1486
1487                 l = hashmap_get(m->links, INT_TO_PTR(ifindex));
1488                 if (!l) /* link vanished */
1489                         goto rm;
1490
1491                 if (l->is_managed) /* now managed by networkd, hence the bus settings are useless */
1492                         goto rm;
1493
1494                 continue;
1495
1496         rm:
1497                 p = path_join("/run/systemd/resolve/netif", de->d_name);
1498                 if (!p) {
1499                         log_oom();
1500                         return;
1501                 }
1502
1503                 (void) unlink(p);
1504         }
1505 }
1506
1507 bool manager_next_dnssd_names(Manager *m) {
1508         DnssdService *s;
1509         bool tried = false;
1510         int r;
1511
1512         assert(m);
1513
1514         HASHMAP_FOREACH(s, m->dnssd_services) {
1515                 _cleanup_free_ char * new_name = NULL;
1516
1517                 if (!s->withdrawn)
1518                         continue;
1519
1520                 r = manager_next_random_name(s->name_template, &new_name);
1521                 if (r < 0) {
1522                         log_warning_errno(r, "Failed to get new name for service '%s': %m", s->name);
1523                         continue;
1524                 }
1525
1526                 free_and_replace(s->name_template, new_name);
1527
1528                 s->withdrawn = false;
1529
1530                 tried = true;
1531         }
1532
1533         if (tried)
1534                 manager_refresh_rrs(m);
1535
1536         return tried;
1537 }