src/network/networkd-ndisc.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 /***
   3   This file is part of systemd.
   4
   5   Copyright (C) 2014 Intel Corporation. All rights reserved.
   6 ***/
   7
   8 #include <netinet/icmp6.h>
   9 #include <arpa/inet.h>
  10
  11 #include "sd-ndisc.h"
  12
  13 #include "networkd-ndisc.h"
  14 #include "networkd-route.h"
  15
  16 #define NDISC_DNSSL_MAX 64U
  17 #define NDISC_RDNSS_MAX 64U
  18 #define NDISC_PREFIX_LFT_MIN 7200U
  19
  20 static int ndisc_netlink_handler(sd_netlink *rtnl, sd_netlink_message *m, void *userdata) {
  21         _cleanup_(link_unrefp) Link *link = userdata;
  22         int r;
  23
  24         assert(link);
  25         assert(link->ndisc_messages > 0);
  26
  27         link->ndisc_messages--;
  28
  29         r = sd_netlink_message_get_errno(m);
  30         if (r < 0 && r != -EEXIST)
  31                 log_link_error_errno(link, r, "Could not set NDisc route or address: %m");
  32
  33         if (link->ndisc_messages == 0) {
  34                 link->ndisc_configured = true;
  35                 link_check_ready(link);
  36         }
  37
  38         return 1;
  39 }
  40
  41 static void ndisc_router_process_default(Link *link, sd_ndisc_router *rt) {
  42         _cleanup_(route_freep) Route *route = NULL;
  43         struct in6_addr gateway;
  44         uint16_t lifetime;
  45         unsigned preference;
  46         uint32_t mtu;
  47         usec_t time_now;
  48         int r;
  49         Address *address;
  50         Iterator i;
  51
  52         assert(link);
  53         assert(rt);
  54
  55         r = sd_ndisc_router_get_lifetime(rt, &lifetime);
  56         if (r < 0) {
  57                 log_link_warning_errno(link, r, "Failed to get gateway address from RA: %m");
  58                 return;
  59         }
  60         if (lifetime == 0) /* not a default router */
  61                 return;
  62
  63         r = sd_ndisc_router_get_address(rt, &gateway);
  64         if (r < 0) {
  65                 log_link_warning_errno(link, r, "Failed to get gateway address from RA: %m");
  66                 return;
  67         }
  68
  69         SET_FOREACH(address, link->addresses, i) {
  70                 if (!memcmp(&gateway, &address->in_addr.in6,
  71                             sizeof(address->in_addr.in6))) {
  72                         char buffer[INET6_ADDRSTRLEN];
  73
  74                         log_link_debug(link, "No NDisc route added, gateway %s matches local address",
  75                                        inet_ntop(AF_INET6,
  76                                                  &address->in_addr.in6,
  77                                                  buffer, sizeof(buffer)));
  78                         return;
  79                 }
  80         }
  81
  82         SET_FOREACH(address, link->addresses_foreign, i) {
  83                 if (!memcmp(&gateway, &address->in_addr.in6,
  84                             sizeof(address->in_addr.in6))) {
  85                         char buffer[INET6_ADDRSTRLEN];
  86
  87                         log_link_debug(link, "No NDisc route added, gateway %s matches local address",
  88                                        inet_ntop(AF_INET6,
  89                                                  &address->in_addr.in6,
  90                                                  buffer, sizeof(buffer)));
  91                         return;
  92                 }
  93         }
  94
  95         r = sd_ndisc_router_get_preference(rt, &preference);
  96         if (r < 0) {
  97                 log_link_warning_errno(link, r, "Failed to get default router preference from RA: %m");
  98                 return;
  99         }
 100
 101         r = sd_ndisc_router_get_timestamp(rt, clock_boottime_or_monotonic(), &time_now);
 102         if (r < 0) {
 103                 log_link_warning_errno(link, r, "Failed to get RA timestamp: %m");
 104                 return;
 105         }
 106
 107         r = sd_ndisc_router_get_mtu(rt, &mtu);
 108         if (r == -ENODATA)
 109                 mtu = 0;
 110         else if (r < 0) {
 111                 log_link_warning_errno(link, r, "Failed to get default router MTU from RA: %m");
 112                 return;
 113         }
 114
 115         r = route_new(&route);
 116         if (r < 0) {
 117                 log_link_error_errno(link, r, "Could not allocate route: %m");
 118                 return;
 119         }
 120
 121         route->family = AF_INET6;
 122         route->table = link->network->ipv6_accept_ra_route_table;
 123         route->priority = link->network->dhcp_route_metric;
 124         route->protocol = RTPROT_RA;
 125         route->pref = preference;
 126         route->gw.in6 = gateway;
 127         route->lifetime = time_now + lifetime * USEC_PER_SEC;
 128         route->mtu = mtu;
 129
 130         r = route_configure(route, link, ndisc_netlink_handler);
 131         if (r < 0) {
 132                 log_link_warning_errno(link, r, "Could not set default route: %m");
 133                 link_enter_failed(link);
 134                 return;
 135         }
 136
 137         link->ndisc_messages++;
 138 }
 139
 140 static void ndisc_router_process_autonomous_prefix(Link *link, sd_ndisc_router *rt) {
 141         _cleanup_(address_freep) Address *address = NULL;
 142         Address *existing_address;
 143         uint32_t lifetime_valid, lifetime_preferred, lifetime_remaining;
 144         usec_t time_now;
 145         unsigned prefixlen;
 146         int r;
 147
 148         assert(link);
 149         assert(rt);
 150
 151         r = sd_ndisc_router_get_timestamp(rt, clock_boottime_or_monotonic(), &time_now);
 152         if (r < 0) {
 153                 log_link_warning_errno(link, r, "Failed to get RA timestamp: %m");
 154                 return;
 155         }
 156
 157         r = sd_ndisc_router_prefix_get_prefixlen(rt, &prefixlen);
 158         if (r < 0) {
 159                 log_link_error_errno(link, r, "Failed to get prefix length: %m");
 160                 return;
 161         }
 162
 163         r = sd_ndisc_router_prefix_get_valid_lifetime(rt, &lifetime_valid);
 164         if (r < 0) {
 165                 log_link_error_errno(link, r, "Failed to get prefix valid lifetime: %m");
 166                 return;
 167         }
 168
 169         r = sd_ndisc_router_prefix_get_preferred_lifetime(rt, &lifetime_preferred);
 170         if (r < 0) {
 171                 log_link_error_errno(link, r, "Failed to get prefix preferred lifetime: %m");
 172                 return;
 173         }
 174
 175         /* The preferred lifetime is never greater than the valid lifetime */
 176         if (lifetime_preferred > lifetime_valid)
 177                 return;
 178
 179         r = address_new(&address);
 180         if (r < 0) {
 181                 log_link_error_errno(link, r, "Could not allocate address: %m");
 182                 return;
 183         }
 184
 185         address->family = AF_INET6;
 186         r = sd_ndisc_router_prefix_get_address(rt, &address->in_addr.in6);
 187         if (r < 0) {
 188                 log_link_error_errno(link, r, "Failed to get prefix address: %m");
 189                 return;
 190         }
 191
 192         if (in_addr_is_null(AF_INET6, (const union in_addr_union *) &link->network->ipv6_token) == 0)
 193                 memcpy(((char *)&address->in_addr.in6) + 8, ((char *)&link->network->ipv6_token) + 8, 8);
 194         else {
 195                 /* see RFC4291 section 2.5.1 */
 196                 address->in_addr.in6.s6_addr[8]  = link->mac.ether_addr_octet[0];
 197                 address->in_addr.in6.s6_addr[8] ^= 1 << 1;
 198                 address->in_addr.in6.s6_addr[9]  = link->mac.ether_addr_octet[1];
 199                 address->in_addr.in6.s6_addr[10] = link->mac.ether_addr_octet[2];
 200                 address->in_addr.in6.s6_addr[11] = 0xff;
 201                 address->in_addr.in6.s6_addr[12] = 0xfe;
 202                 address->in_addr.in6.s6_addr[13] = link->mac.ether_addr_octet[3];
 203                 address->in_addr.in6.s6_addr[14] = link->mac.ether_addr_octet[4];
 204                 address->in_addr.in6.s6_addr[15] = link->mac.ether_addr_octet[5];
 205         }
 206         address->prefixlen = prefixlen;
 207         address->flags = IFA_F_NOPREFIXROUTE|IFA_F_MANAGETEMPADDR;
 208         address->cinfo.ifa_prefered = lifetime_preferred;
 209
 210         /* see RFC4862 section 5.5.3.e */
 211         r = address_get(link, address->family, &address->in_addr, address->prefixlen, &existing_address);
 212         if (r > 0) {
 213                 lifetime_remaining = existing_address->cinfo.tstamp / 100 + existing_address->cinfo.ifa_valid - time_now / USEC_PER_SEC;
 214                 if (lifetime_valid > NDISC_PREFIX_LFT_MIN || lifetime_valid > lifetime_remaining)
 215                         address->cinfo.ifa_valid = lifetime_valid;
 216                 else if (lifetime_remaining <= NDISC_PREFIX_LFT_MIN)
 217                         address->cinfo.ifa_valid = lifetime_remaining;
 218                 else
 219                         address->cinfo.ifa_valid = NDISC_PREFIX_LFT_MIN;
 220         } else if (lifetime_valid > 0)
 221                 address->cinfo.ifa_valid = lifetime_valid;
 222         else
 223                 return; /* see RFC4862 section 5.5.3.d */
 224
 225         if (address->cinfo.ifa_valid == 0)
 226                 return;
 227
 228         r = address_configure(address, link, ndisc_netlink_handler, true);
 229         if (r < 0) {
 230                 log_link_warning_errno(link, r, "Could not set SLAAC address: %m");
 231                 link_enter_failed(link);
 232                 return;
 233         }
 234
 235         link->ndisc_messages++;
 236 }
 237
 238 static void ndisc_router_process_onlink_prefix(Link *link, sd_ndisc_router *rt) {
 239         _cleanup_(route_freep) Route *route = NULL;
 240         usec_t time_now;
 241         uint32_t lifetime;
 242         unsigned prefixlen;
 243         int r;
 244
 245         assert(link);
 246         assert(rt);
 247
 248         r = sd_ndisc_router_get_timestamp(rt, clock_boottime_or_monotonic(), &time_now);
 249         if (r < 0) {
 250                 log_link_warning_errno(link, r, "Failed to get RA timestamp: %m");
 251                 return;
 252         }
 253
 254         r = sd_ndisc_router_prefix_get_prefixlen(rt, &prefixlen);
 255         if (r < 0) {
 256                 log_link_error_errno(link, r, "Failed to get prefix length: %m");
 257                 return;
 258         }
 259
 260         r = sd_ndisc_router_prefix_get_valid_lifetime(rt, &lifetime);
 261         if (r < 0) {
 262                 log_link_error_errno(link, r, "Failed to get prefix lifetime: %m");
 263                 return;
 264         }
 265
 266         r = route_new(&route);
 267         if (r < 0) {
 268                 log_link_error_errno(link, r, "Could not allocate route: %m");
 269                 return;
 270         }
 271
 272         route->family = AF_INET6;
 273         route->table = link->network->ipv6_accept_ra_route_table;
 274         route->priority = link->network->dhcp_route_metric;
 275         route->protocol = RTPROT_RA;
 276         route->flags = RTM_F_PREFIX;
 277         route->dst_prefixlen = prefixlen;
 278         route->lifetime = time_now + lifetime * USEC_PER_SEC;
 279
 280         r = sd_ndisc_router_prefix_get_address(rt, &route->dst.in6);
 281         if (r < 0) {
 282                 log_link_error_errno(link, r, "Failed to get prefix address: %m");
 283                 return;
 284         }
 285
 286         r = route_configure(route, link, ndisc_netlink_handler);
 287         if (r < 0) {
 288                 log_link_warning_errno(link, r, "Could not set prefix route: %m");
 289                 link_enter_failed(link);
 290                 return;
 291         }
 292
 293         link->ndisc_messages++;
 294 }
 295
 296 static void ndisc_router_process_route(Link *link, sd_ndisc_router *rt) {
 297         _cleanup_(route_freep) Route *route = NULL;
 298         struct in6_addr gateway;
 299         uint32_t lifetime;
 300         unsigned preference, prefixlen;
 301         usec_t time_now;
 302         int r;
 303
 304         assert(link);
 305
 306         r = sd_ndisc_router_route_get_lifetime(rt, &lifetime);
 307         if (r < 0) {
 308                 log_link_warning_errno(link, r, "Failed to get gateway address from RA: %m");
 309                 return;
 310         }
 311         if (lifetime == 0)
 312                 return;
 313
 314         r = sd_ndisc_router_get_address(rt, &gateway);
 315         if (r < 0) {
 316                 log_link_warning_errno(link, r, "Failed to get gateway address from RA: %m");
 317                 return;
 318         }
 319
 320         r = sd_ndisc_router_route_get_prefixlen(rt, &prefixlen);
 321         if (r < 0) {
 322                 log_link_warning_errno(link, r, "Failed to get route prefix length: %m");
 323                 return;
 324         }
 325
 326         r = sd_ndisc_router_route_get_preference(rt, &preference);
 327         if (r < 0) {
 328                 log_link_warning_errno(link, r, "Failed to get default router preference from RA: %m");
 329                 return;
 330         }
 331
 332         r = sd_ndisc_router_get_timestamp(rt, clock_boottime_or_monotonic(), &time_now);
 333         if (r < 0) {
 334                 log_link_warning_errno(link, r, "Failed to get RA timestamp: %m");
 335                 return;
 336         }
 337
 338         r = route_new(&route);
 339         if (r < 0) {
 340                 log_link_error_errno(link, r, "Could not allocate route: %m");
 341                 return;
 342         }
 343
 344         route->family = AF_INET6;
 345         route->table = link->network->ipv6_accept_ra_route_table;
 346         route->protocol = RTPROT_RA;
 347         route->pref = preference;
 348         route->gw.in6 = gateway;
 349         route->dst_prefixlen = prefixlen;
 350         route->lifetime = time_now + lifetime * USEC_PER_SEC;
 351
 352         r = sd_ndisc_router_route_get_address(rt, &route->dst.in6);
 353         if (r < 0) {
 354                 log_link_error_errno(link, r, "Failed to get route address: %m");
 355                 return;
 356         }
 357
 358         r = route_configure(route, link, ndisc_netlink_handler);
 359         if (r < 0) {
 360                 log_link_warning_errno(link, r, "Could not set additional route: %m");
 361                 link_enter_failed(link);
 362                 return;
 363         }
 364
 365         link->ndisc_messages++;
 366 }
 367
 368 static void ndisc_rdnss_hash_func(const void *p, struct siphash *state) {
 369         const NDiscRDNSS *x = p;
 370
 371         siphash24_compress(&x->address, sizeof(x->address), state);
 372 }
 373
 374 static int ndisc_rdnss_compare_func(const void *_a, const void *_b) {
 375         const NDiscRDNSS *a = _a, *b = _b;
 376
 377         return memcmp(&a->address, &b->address, sizeof(a->address));
 378 }
 379
 380 static const struct hash_ops ndisc_rdnss_hash_ops = {
 381         .hash = ndisc_rdnss_hash_func,
 382         .compare = ndisc_rdnss_compare_func
 383 };
 384
 385 static void ndisc_router_process_rdnss(Link *link, sd_ndisc_router *rt) {
 386         uint32_t lifetime;
 387         const struct in6_addr *a;
 388         usec_t time_now;
 389         int i, n, r;
 390
 391         assert(link);
 392         assert(rt);
 393
 394         r = sd_ndisc_router_get_timestamp(rt, clock_boottime_or_monotonic(), &time_now);
 395         if (r < 0) {
 396                 log_link_warning_errno(link, r, "Failed to get RA timestamp: %m");
 397                 return;
 398         }
 399
 400         r = sd_ndisc_router_rdnss_get_lifetime(rt, &lifetime);
 401         if (r < 0) {
 402                 log_link_warning_errno(link, r, "Failed to get RDNSS lifetime: %m");
 403                 return;
 404         }
 405
 406         n = sd_ndisc_router_rdnss_get_addresses(rt, &a);
 407         if (n < 0) {
 408                 log_link_warning_errno(link, n, "Failed to get RDNSS addresses: %m");
 409                 return;
 410         }
 411
 412         for (i = 0; i < n; i++) {
 413                 NDiscRDNSS d = {
 414                         .address = a[i]
 415                 }, *x;
 416
 417                 if (lifetime == 0) {
 418                         (void) set_remove(link->ndisc_rdnss, &d);
 419                         link_dirty(link);
 420                         continue;
 421                 }
 422
 423                 x = set_get(link->ndisc_rdnss, &d);
 424                 if (x) {
 425                         x->valid_until = time_now + lifetime * USEC_PER_SEC;
 426                         continue;
 427                 }
 428
 429                 ndisc_vacuum(link);
 430
 431                 if (set_size(link->ndisc_rdnss) >= NDISC_RDNSS_MAX) {
 432                         log_link_warning(link, "Too many RDNSS records per link, ignoring.");
 433                         continue;
 434                 }
 435
 436                 r = set_ensure_allocated(&link->ndisc_rdnss, &ndisc_rdnss_hash_ops);
 437                 if (r < 0) {
 438                         log_oom();
 439                         return;
 440                 }
 441
 442                 x = new0(NDiscRDNSS, 1);
 443                 if (!x) {
 444                         log_oom();
 445                         return;
 446                 }
 447
 448                 x->address = a[i];
 449                 x->valid_until = time_now + lifetime * USEC_PER_SEC;
 450
 451                 r = set_put(link->ndisc_rdnss, x);
 452                 if (r < 0) {
 453                         free(x);
 454                         log_oom();
 455                         return;
 456                 }
 457
 458                 assert(r > 0);
 459                 link_dirty(link);
 460         }
 461 }
 462
 463 static void ndisc_dnssl_hash_func(const void *p, struct siphash *state) {
 464         const NDiscDNSSL *x = p;
 465
 466         siphash24_compress(NDISC_DNSSL_DOMAIN(x), strlen(NDISC_DNSSL_DOMAIN(x)), state);
 467 }
 468
 469 static int ndisc_dnssl_compare_func(const void *_a, const void *_b) {
 470         const NDiscDNSSL *a = _a, *b = _b;
 471
 472         return strcmp(NDISC_DNSSL_DOMAIN(a), NDISC_DNSSL_DOMAIN(b));
 473 }
 474
 475 static const struct hash_ops ndisc_dnssl_hash_ops = {
 476         .hash = ndisc_dnssl_hash_func,
 477         .compare = ndisc_dnssl_compare_func
 478 };
 479
 480 static void ndisc_router_process_dnssl(Link *link, sd_ndisc_router *rt) {
 481         _cleanup_strv_free_ char **l = NULL;
 482         uint32_t lifetime;
 483         usec_t time_now;
 484         char **i;
 485         int r;
 486
 487         assert(link);
 488         assert(rt);
 489
 490         r = sd_ndisc_router_get_timestamp(rt, clock_boottime_or_monotonic(), &time_now);
 491         if (r < 0) {
 492                 log_link_warning_errno(link, r, "Failed to get RA timestamp: %m");
 493                 return;
 494         }
 495
 496         r = sd_ndisc_router_dnssl_get_lifetime(rt, &lifetime);
 497         if (r < 0) {
 498                 log_link_warning_errno(link, r, "Failed to get RDNSS lifetime: %m");
 499                 return;
 500         }
 501
 502         r = sd_ndisc_router_dnssl_get_domains(rt, &l);
 503         if (r < 0) {
 504                 log_link_warning_errno(link, r, "Failed to get RDNSS addresses: %m");
 505                 return;
 506         }
 507
 508         STRV_FOREACH(i, l) {
 509                 _cleanup_free_ NDiscDNSSL *s;
 510                 NDiscDNSSL *x;
 511
 512                 s = malloc0(ALIGN(sizeof(NDiscDNSSL)) + strlen(*i) + 1);
 513                 if (!s) {
 514                         log_oom();
 515                         return;
 516                 }
 517
 518                 strcpy(NDISC_DNSSL_DOMAIN(s), *i);
 519
 520                 if (lifetime == 0) {
 521                         (void) set_remove(link->ndisc_dnssl, s);
 522                         link_dirty(link);
 523                         continue;
 524                 }
 525
 526                 x = set_get(link->ndisc_dnssl, s);
 527                 if (x) {
 528                         x->valid_until = time_now + lifetime * USEC_PER_SEC;
 529                         continue;
 530                 }
 531
 532                 ndisc_vacuum(link);
 533
 534                 if (set_size(link->ndisc_dnssl) >= NDISC_DNSSL_MAX) {
 535                         log_link_warning(link, "Too many DNSSL records per link, ignoring.");
 536                         continue;
 537                 }
 538
 539                 r = set_ensure_allocated(&link->ndisc_dnssl, &ndisc_dnssl_hash_ops);
 540                 if (r < 0) {
 541                         log_oom();
 542                         return;
 543                 }
 544
 545                 s->valid_until = time_now + lifetime * USEC_PER_SEC;
 546
 547                 r = set_put(link->ndisc_dnssl, s);
 548                 if (r < 0) {
 549                         log_oom();
 550                         return;
 551                 }
 552
 553                 s = NULL;
 554                 assert(r > 0);
 555                 link_dirty(link);
 556         }
 557 }
 558
 559 static void ndisc_router_process_options(Link *link, sd_ndisc_router *rt) {
 560         int r;
 561
 562         assert(link);
 563         assert(rt);
 564
 565         r = sd_ndisc_router_option_rewind(rt);
 566         for (;;) {
 567                 uint8_t type;
 568
 569                 if (r < 0) {
 570                         log_link_warning_errno(link, r, "Failed to iterate through options: %m");
 571                         return;
 572                 }
 573                 if (r == 0) /* EOF */
 574                         break;
 575
 576                 r = sd_ndisc_router_option_get_type(rt, &type);
 577                 if (r < 0) {
 578                         log_link_warning_errno(link, r, "Failed to get RA option type: %m");
 579                         return;
 580                 }
 581
 582                 switch (type) {
 583
 584                 case SD_NDISC_OPTION_PREFIX_INFORMATION: {
 585                         uint8_t flags;
 586
 587                         r = sd_ndisc_router_prefix_get_flags(rt, &flags);
 588                         if (r < 0) {
 589                                 log_link_warning_errno(link, r, "Failed to get RA prefix flags: %m");
 590                                 return;
 591                         }
 592
 593                         if (flags & ND_OPT_PI_FLAG_ONLINK)
 594                                 ndisc_router_process_onlink_prefix(link, rt);
 595                         if (flags & ND_OPT_PI_FLAG_AUTO)
 596                                 ndisc_router_process_autonomous_prefix(link, rt);
 597
 598                         break;
 599                 }
 600
 601                 case SD_NDISC_OPTION_ROUTE_INFORMATION:
 602                         ndisc_router_process_route(link, rt);
 603                         break;
 604
 605                 case SD_NDISC_OPTION_RDNSS:
 606                         if (link->network->ipv6_accept_ra_use_dns)
 607                                 ndisc_router_process_rdnss(link, rt);
 608                         break;
 609
 610                 case SD_NDISC_OPTION_DNSSL:
 611                         if (link->network->ipv6_accept_ra_use_dns)
 612                                 ndisc_router_process_dnssl(link, rt);
 613                         break;
 614                 }
 615
 616                 r = sd_ndisc_router_option_next(rt);
 617         }
 618 }
 619
 620 static void ndisc_router_handler(Link *link, sd_ndisc_router *rt) {
 621         uint64_t flags;
 622         int r;
 623
 624         assert(link);
 625         assert(link->network);
 626         assert(link->manager);
 627         assert(rt);
 628
 629         r = sd_ndisc_router_get_flags(rt, &flags);
 630         if (r < 0) {
 631                 log_link_warning_errno(link, r, "Failed to get RA flags: %m");
 632                 return;
 633         }
 634
 635         if (flags & (ND_RA_FLAG_MANAGED | ND_RA_FLAG_OTHER)) {
 636                 /* (re)start DHCPv6 client in stateful or stateless mode according to RA flags */
 637                 r = dhcp6_request_address(link, !(flags & ND_RA_FLAG_MANAGED));
 638                 if (r < 0 && r != -EBUSY)
 639                         log_link_warning_errno(link, r, "Could not acquire DHCPv6 lease on NDisc request: %m");
 640                 else
 641                         log_link_debug(link, "Acquiring DHCPv6 lease on NDisc request");
 642         }
 643
 644         ndisc_router_process_default(link, rt);
 645         ndisc_router_process_options(link, rt);
 646 }
 647
 648 static void ndisc_handler(sd_ndisc *nd, sd_ndisc_event event, sd_ndisc_router *rt, void *userdata) {
 649         Link *link = userdata;
 650
 651         assert(link);
 652
 653         if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER))
 654                 return;
 655
 656         switch (event) {
 657
 658         case SD_NDISC_EVENT_ROUTER:
 659                 ndisc_router_handler(link, rt);
 660                 break;
 661
 662         case SD_NDISC_EVENT_TIMEOUT:
 663                 link->ndisc_configured = true;
 664                 link_check_ready(link);
 665
 666                 break;
 667         default:
 668                 log_link_warning(link, "IPv6 Neighbor Discovery unknown event: %d", event);
 669         }
 670 }
 671
 672 int ndisc_configure(Link *link) {
 673         int r;
 674
 675         assert(link);
 676
 677         r = sd_ndisc_new(&link->ndisc);
 678         if (r < 0)
 679                 return r;
 680
 681         r = sd_ndisc_attach_event(link->ndisc, NULL, 0);
 682         if (r < 0)
 683                 return r;
 684
 685         r = sd_ndisc_set_mac(link->ndisc, &link->mac);
 686         if (r < 0)
 687                 return r;
 688
 689         r = sd_ndisc_set_ifindex(link->ndisc, link->ifindex);
 690         if (r < 0)
 691                 return r;
 692
 693         r = sd_ndisc_set_callback(link->ndisc, ndisc_handler, link);
 694         if (r < 0)
 695                 return r;
 696
 697         return 0;
 698 }
 699
 700 void ndisc_vacuum(Link *link) {
 701         NDiscRDNSS *r;
 702         NDiscDNSSL *d;
 703         Iterator i;
 704         usec_t time_now;
 705
 706         assert(link);
 707
 708         /* Removes all RDNSS and DNSSL entries whose validity time has passed */
 709
 710         time_now = now(clock_boottime_or_monotonic());
 711
 712         SET_FOREACH(r, link->ndisc_rdnss, i)
 713                 if (r->valid_until < time_now) {
 714                         free(set_remove(link->ndisc_rdnss, r));
 715                         link_dirty(link);
 716                 }
 717
 718         SET_FOREACH(d, link->ndisc_dnssl, i)
 719                 if (d->valid_until < time_now) {
 720                         free(set_remove(link->ndisc_dnssl, d));
 721                         link_dirty(link);
 722                 }
 723 }
 724
 725 void ndisc_flush(Link *link) {
 726         assert(link);
 727
 728         /* Removes all RDNSS and DNSSL entries, without exception */
 729
 730         link->ndisc_rdnss = set_free_free(link->ndisc_rdnss);
 731         link->ndisc_dnssl = set_free_free(link->ndisc_dnssl);
 732 }