src/network/networkd-ndisc.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 /***
   3   Copyright © 2014 Intel Corporation. All rights reserved.
   4 ***/
   5
   6 #include <netinet/icmp6.h>
   7 #include <arpa/inet.h>
   8
   9 #include "sd-ndisc.h"
  10
  11 #include "missing_network.h"
  12 #include "networkd-ndisc.h"
  13 #include "networkd-route.h"
  14 #include "strv.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_message_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
  21         int r;
  22
  23         assert(link);
  24         assert(link->ndisc_messages > 0);
  25
  26         link->ndisc_messages--;
  27
  28         r = sd_netlink_message_get_errno(m);
  29         if (r < 0 && r != -EEXIST)
  30                 log_link_error_errno(link, r, "Could not set NDisc route or address: %m");
  31
  32         if (link->ndisc_messages == 0) {
  33                 link->ndisc_configured = true;
  34                 link_check_ready(link);
  35         }
  36
  37         return 1;
  38 }
  39
  40 static int ndisc_router_process_default(Link *link, sd_ndisc_router *rt) {
  41         _cleanup_(route_freep) Route *route = NULL;
  42         union in_addr_union gateway;
  43         uint16_t lifetime;
  44         unsigned preference;
  45         uint32_t mtu;
  46         usec_t time_now;
  47         int r;
  48         Address *address;
  49         Iterator i;
  50
  51         assert(link);
  52         assert(rt);
  53
  54         r = sd_ndisc_router_get_lifetime(rt, &lifetime);
  55         if (r < 0)
  56                 return log_link_warning_errno(link, r, "Failed to get gateway address from RA: %m");
  57
  58         if (lifetime == 0) /* not a default router */
  59                 return 0;
  60
  61         r = sd_ndisc_router_get_address(rt, &gateway.in6);
  62         if (r < 0)
  63                 return log_link_warning_errno(link, r, "Failed to get gateway address from RA: %m");
  64
  65         SET_FOREACH(address, link->addresses, i) {
  66                 if (address->family != AF_INET6)
  67                         continue;
  68                 if (in_addr_equal(AF_INET6, &gateway, &address->in_addr)) {
  69                         _cleanup_free_ char *buffer = NULL;
  70
  71                         (void) in_addr_to_string(AF_INET6, &address->in_addr, &buffer);
  72                         log_link_debug(link, "No NDisc route added, gateway %s matches local address",
  73                                        strnull(buffer));
  74                         return 0;
  75                 }
  76         }
  77
  78         SET_FOREACH(address, link->addresses_foreign, i) {
  79                 if (address->family != AF_INET6)
  80                         continue;
  81                 if (in_addr_equal(AF_INET6, &gateway, &address->in_addr)) {
  82                         _cleanup_free_ char *buffer = NULL;
  83
  84                         (void) in_addr_to_string(AF_INET6, &address->in_addr, &buffer);
  85                         log_link_debug(link, "No NDisc route added, gateway %s matches local address",
  86                                        strnull(buffer));
  87                         return 0;
  88                 }
  89         }
  90
  91         r = sd_ndisc_router_get_preference(rt, &preference);
  92         if (r < 0)
  93                 return log_link_warning_errno(link, r, "Failed to get default router preference from RA: %m");
  94
  95         r = sd_ndisc_router_get_timestamp(rt, clock_boottime_or_monotonic(), &time_now);
  96         if (r < 0)
  97                 return log_link_warning_errno(link, r, "Failed to get RA timestamp: %m");
  98
  99         r = sd_ndisc_router_get_mtu(rt, &mtu);
 100         if (r == -ENODATA)
 101                 mtu = 0;
 102         else if (r < 0)
 103                 return log_link_warning_errno(link, r, "Failed to get default router MTU from RA: %m");
 104
 105         r = route_new(&route);
 106         if (r < 0)
 107                 return log_link_error_errno(link, r, "Could not allocate route: %m");
 108
 109         route->family = AF_INET6;
 110         route->table = link_get_ipv6_accept_ra_route_table(link);
 111         route->priority = link->network->dhcp_route_metric;
 112         route->protocol = RTPROT_RA;
 113         route->pref = preference;
 114         route->gw = gateway;
 115         route->lifetime = time_now + lifetime * USEC_PER_SEC;
 116         route->mtu = mtu;
 117
 118         r = route_configure(route, link, ndisc_netlink_message_handler);
 119         if (r < 0) {
 120                 log_link_warning_errno(link, r, "Could not set default route: %m");
 121                 link_enter_failed(link);
 122                 return r;
 123         }
 124
 125         link->ndisc_messages++;
 126
 127         return 0;
 128 }
 129
 130 static int ndisc_router_process_autonomous_prefix(Link *link, sd_ndisc_router *rt) {
 131         _cleanup_(address_freep) Address *address = NULL;
 132         Address *existing_address;
 133         uint32_t lifetime_valid, lifetime_preferred, lifetime_remaining;
 134         usec_t time_now;
 135         unsigned prefixlen;
 136         int r;
 137
 138         assert(link);
 139         assert(rt);
 140
 141         r = sd_ndisc_router_get_timestamp(rt, clock_boottime_or_monotonic(), &time_now);
 142         if (r < 0)
 143                 return log_link_warning_errno(link, r, "Failed to get RA timestamp: %m");
 144
 145         r = sd_ndisc_router_prefix_get_prefixlen(rt, &prefixlen);
 146         if (r < 0)
 147                 return log_link_error_errno(link, r, "Failed to get prefix length: %m");
 148
 149         r = sd_ndisc_router_prefix_get_valid_lifetime(rt, &lifetime_valid);
 150         if (r < 0)
 151                 return log_link_error_errno(link, r, "Failed to get prefix valid lifetime: %m");
 152
 153         r = sd_ndisc_router_prefix_get_preferred_lifetime(rt, &lifetime_preferred);
 154         if (r < 0)
 155                 return log_link_error_errno(link, r, "Failed to get prefix preferred lifetime: %m");
 156
 157         /* The preferred lifetime is never greater than the valid lifetime */
 158         if (lifetime_preferred > lifetime_valid)
 159                 return 0;
 160
 161         r = address_new(&address);
 162         if (r < 0)
 163                 return log_link_error_errno(link, r, "Could not allocate address: %m");
 164
 165         address->family = AF_INET6;
 166         r = sd_ndisc_router_prefix_get_address(rt, &address->in_addr.in6);
 167         if (r < 0)
 168                 return log_link_error_errno(link, r, "Failed to get prefix address: %m");
 169
 170         if (in_addr_is_null(AF_INET6, (const union in_addr_union *) &link->network->ipv6_token) == 0)
 171                 memcpy(((char *)&address->in_addr.in6) + 8, ((char *)&link->network->ipv6_token) + 8, 8);
 172         else {
 173                 /* see RFC4291 section 2.5.1 */
 174                 address->in_addr.in6.s6_addr[8]  = link->mac.ether_addr_octet[0];
 175                 address->in_addr.in6.s6_addr[8] ^= 1 << 1;
 176                 address->in_addr.in6.s6_addr[9]  = link->mac.ether_addr_octet[1];
 177                 address->in_addr.in6.s6_addr[10] = link->mac.ether_addr_octet[2];
 178                 address->in_addr.in6.s6_addr[11] = 0xff;
 179                 address->in_addr.in6.s6_addr[12] = 0xfe;
 180                 address->in_addr.in6.s6_addr[13] = link->mac.ether_addr_octet[3];
 181                 address->in_addr.in6.s6_addr[14] = link->mac.ether_addr_octet[4];
 182                 address->in_addr.in6.s6_addr[15] = link->mac.ether_addr_octet[5];
 183         }
 184         address->prefixlen = prefixlen;
 185         address->flags = IFA_F_NOPREFIXROUTE|IFA_F_MANAGETEMPADDR;
 186         address->cinfo.ifa_prefered = lifetime_preferred;
 187
 188         /* see RFC4862 section 5.5.3.e */
 189         r = address_get(link, address->family, &address->in_addr, address->prefixlen, &existing_address);
 190         if (r > 0) {
 191                 lifetime_remaining = existing_address->cinfo.tstamp / 100 + existing_address->cinfo.ifa_valid - time_now / USEC_PER_SEC;
 192                 if (lifetime_valid > NDISC_PREFIX_LFT_MIN || lifetime_valid > lifetime_remaining)
 193                         address->cinfo.ifa_valid = lifetime_valid;
 194                 else if (lifetime_remaining <= NDISC_PREFIX_LFT_MIN)
 195                         address->cinfo.ifa_valid = lifetime_remaining;
 196                 else
 197                         address->cinfo.ifa_valid = NDISC_PREFIX_LFT_MIN;
 198         } else if (lifetime_valid > 0)
 199                 address->cinfo.ifa_valid = lifetime_valid;
 200         else
 201                 return 0; /* see RFC4862 section 5.5.3.d */
 202
 203         if (address->cinfo.ifa_valid == 0)
 204                 return 0;
 205
 206         r = address_configure(address, link, ndisc_netlink_message_handler, true);
 207         if (r < 0) {
 208                 log_link_warning_errno(link, r, "Could not set SLAAC address: %m");
 209                 link_enter_failed(link);
 210                 return r;
 211         }
 212
 213         link->ndisc_messages++;
 214
 215         return 0;
 216 }
 217
 218 static int ndisc_router_process_onlink_prefix(Link *link, sd_ndisc_router *rt) {
 219         _cleanup_(route_freep) Route *route = NULL;
 220         usec_t time_now;
 221         uint32_t lifetime;
 222         unsigned prefixlen;
 223         int r;
 224
 225         assert(link);
 226         assert(rt);
 227
 228         r = sd_ndisc_router_get_timestamp(rt, clock_boottime_or_monotonic(), &time_now);
 229         if (r < 0)
 230                 return log_link_warning_errno(link, r, "Failed to get RA timestamp: %m");
 231
 232         r = sd_ndisc_router_prefix_get_prefixlen(rt, &prefixlen);
 233         if (r < 0)
 234                 return log_link_error_errno(link, r, "Failed to get prefix length: %m");
 235
 236         r = sd_ndisc_router_prefix_get_valid_lifetime(rt, &lifetime);
 237         if (r < 0)
 238                 return log_link_error_errno(link, r, "Failed to get prefix lifetime: %m");
 239
 240         r = route_new(&route);
 241         if (r < 0)
 242                 return log_link_error_errno(link, r, "Could not allocate route: %m");
 243
 244         route->family = AF_INET6;
 245         route->table = link_get_ipv6_accept_ra_route_table(link);
 246         route->priority = link->network->dhcp_route_metric;
 247         route->protocol = RTPROT_RA;
 248         route->flags = RTM_F_PREFIX;
 249         route->dst_prefixlen = prefixlen;
 250         route->lifetime = time_now + lifetime * USEC_PER_SEC;
 251
 252         r = sd_ndisc_router_prefix_get_address(rt, &route->dst.in6);
 253         if (r < 0)
 254                 return log_link_error_errno(link, r, "Failed to get prefix address: %m");
 255
 256         r = route_configure(route, link, ndisc_netlink_message_handler);
 257         if (r < 0) {
 258                 log_link_warning_errno(link, r, "Could not set prefix route: %m");
 259                 link_enter_failed(link);
 260                 return r;
 261         }
 262
 263         link->ndisc_messages++;
 264
 265         return 0;
 266 }
 267
 268 static int ndisc_router_process_route(Link *link, sd_ndisc_router *rt) {
 269         _cleanup_(route_freep) Route *route = NULL;
 270         struct in6_addr gateway;
 271         uint32_t lifetime;
 272         unsigned preference, prefixlen;
 273         usec_t time_now;
 274         int r;
 275
 276         assert(link);
 277
 278         r = sd_ndisc_router_route_get_lifetime(rt, &lifetime);
 279         if (r < 0)
 280                 return log_link_warning_errno(link, r, "Failed to get gateway address from RA: %m");
 281
 282         if (lifetime == 0)
 283                 return 0;
 284
 285         r = sd_ndisc_router_get_address(rt, &gateway);
 286         if (r < 0)
 287                 return log_link_warning_errno(link, r, "Failed to get gateway address from RA: %m");
 288
 289         r = sd_ndisc_router_route_get_prefixlen(rt, &prefixlen);
 290         if (r < 0)
 291                 return log_link_warning_errno(link, r, "Failed to get route prefix length: %m");
 292
 293         r = sd_ndisc_router_route_get_preference(rt, &preference);
 294         if (r < 0)
 295                 return log_link_warning_errno(link, r, "Failed to get default router preference from RA: %m");
 296
 297         r = sd_ndisc_router_get_timestamp(rt, clock_boottime_or_monotonic(), &time_now);
 298         if (r < 0)
 299                 return log_link_warning_errno(link, r, "Failed to get RA timestamp: %m");
 300
 301         r = route_new(&route);
 302         if (r < 0)
 303                 return log_link_error_errno(link, r, "Could not allocate route: %m");
 304
 305         route->family = AF_INET6;
 306         route->table = link_get_ipv6_accept_ra_route_table(link);
 307         route->protocol = RTPROT_RA;
 308         route->pref = preference;
 309         route->gw.in6 = gateway;
 310         route->dst_prefixlen = prefixlen;
 311         route->lifetime = time_now + lifetime * USEC_PER_SEC;
 312
 313         r = sd_ndisc_router_route_get_address(rt, &route->dst.in6);
 314         if (r < 0)
 315                 return log_link_error_errno(link, r, "Failed to get route address: %m");
 316
 317         r = route_configure(route, link, ndisc_netlink_message_handler);
 318         if (r < 0) {
 319                 log_link_warning_errno(link, r, "Could not set additional route: %m");
 320                 link_enter_failed(link);
 321                 return r;
 322         }
 323
 324         link->ndisc_messages++;
 325
 326         return 0;
 327 }
 328
 329 static void ndisc_rdnss_hash_func(const NDiscRDNSS *x, struct siphash *state) {
 330         siphash24_compress(&x->address, sizeof(x->address), state);
 331 }
 332
 333 static int ndisc_rdnss_compare_func(const NDiscRDNSS *a, const NDiscRDNSS *b) {
 334         return memcmp(&a->address, &b->address, sizeof(a->address));
 335 }
 336
 337 DEFINE_PRIVATE_HASH_OPS(ndisc_rdnss_hash_ops, NDiscRDNSS, ndisc_rdnss_hash_func, ndisc_rdnss_compare_func);
 338
 339 static int ndisc_router_process_rdnss(Link *link, sd_ndisc_router *rt) {
 340         uint32_t lifetime;
 341         const struct in6_addr *a;
 342         usec_t time_now;
 343         int i, n, r;
 344
 345         assert(link);
 346         assert(rt);
 347
 348         r = sd_ndisc_router_get_timestamp(rt, clock_boottime_or_monotonic(), &time_now);
 349         if (r < 0)
 350                 return log_link_warning_errno(link, r, "Failed to get RA timestamp: %m");
 351
 352         r = sd_ndisc_router_rdnss_get_lifetime(rt, &lifetime);
 353         if (r < 0)
 354                 return log_link_warning_errno(link, r, "Failed to get RDNSS lifetime: %m");
 355
 356         n = sd_ndisc_router_rdnss_get_addresses(rt, &a);
 357         if (n < 0)
 358                 return log_link_warning_errno(link, n, "Failed to get RDNSS addresses: %m");
 359
 360         for (i = 0; i < n; i++) {
 361                 _cleanup_free_ NDiscRDNSS *x = NULL;
 362                 NDiscRDNSS d = {
 363                         .address = a[i],
 364                 }, *y;
 365
 366                 if (lifetime == 0) {
 367                         (void) set_remove(link->ndisc_rdnss, &d);
 368                         link_dirty(link);
 369                         continue;
 370                 }
 371
 372                 y = set_get(link->ndisc_rdnss, &d);
 373                 if (y) {
 374                         y->valid_until = time_now + lifetime * USEC_PER_SEC;
 375                         continue;
 376                 }
 377
 378                 ndisc_vacuum(link);
 379
 380                 if (set_size(link->ndisc_rdnss) >= NDISC_RDNSS_MAX) {
 381                         log_link_warning(link, "Too many RDNSS records per link, ignoring.");
 382                         continue;
 383                 }
 384
 385                 r = set_ensure_allocated(&link->ndisc_rdnss, &ndisc_rdnss_hash_ops);
 386                 if (r < 0)
 387                         return log_oom();
 388
 389                 x = new(NDiscRDNSS, 1);
 390                 if (!x)
 391                         return log_oom();
 392
 393                 *x = (NDiscRDNSS) {
 394                         .address = a[i],
 395                         .valid_until = time_now + lifetime * USEC_PER_SEC,
 396                 };
 397
 398                 r = set_put(link->ndisc_rdnss, x);
 399                 if (r < 0)
 400                         return log_oom();
 401
 402                 TAKE_PTR(x);
 403
 404                 assert(r > 0);
 405                 link_dirty(link);
 406         }
 407
 408         return 0;
 409 }
 410
 411 static void ndisc_dnssl_hash_func(const NDiscDNSSL *x, struct siphash *state) {
 412         siphash24_compress(NDISC_DNSSL_DOMAIN(x), strlen(NDISC_DNSSL_DOMAIN(x)), state);
 413 }
 414
 415 static int ndisc_dnssl_compare_func(const NDiscDNSSL *a, const NDiscDNSSL *b) {
 416         return strcmp(NDISC_DNSSL_DOMAIN(a), NDISC_DNSSL_DOMAIN(b));
 417 }
 418
 419 DEFINE_PRIVATE_HASH_OPS(ndisc_dnssl_hash_ops, NDiscDNSSL, ndisc_dnssl_hash_func, ndisc_dnssl_compare_func);
 420
 421 static void ndisc_router_process_dnssl(Link *link, sd_ndisc_router *rt) {
 422         _cleanup_strv_free_ char **l = NULL;
 423         uint32_t lifetime;
 424         usec_t time_now;
 425         char **i;
 426         int r;
 427
 428         assert(link);
 429         assert(rt);
 430
 431         r = sd_ndisc_router_get_timestamp(rt, clock_boottime_or_monotonic(), &time_now);
 432         if (r < 0) {
 433                 log_link_warning_errno(link, r, "Failed to get RA timestamp: %m");
 434                 return;
 435         }
 436
 437         r = sd_ndisc_router_dnssl_get_lifetime(rt, &lifetime);
 438         if (r < 0) {
 439                 log_link_warning_errno(link, r, "Failed to get RDNSS lifetime: %m");
 440                 return;
 441         }
 442
 443         r = sd_ndisc_router_dnssl_get_domains(rt, &l);
 444         if (r < 0) {
 445                 log_link_warning_errno(link, r, "Failed to get RDNSS addresses: %m");
 446                 return;
 447         }
 448
 449         STRV_FOREACH(i, l) {
 450                 _cleanup_free_ NDiscDNSSL *s;
 451                 NDiscDNSSL *x;
 452
 453                 s = malloc0(ALIGN(sizeof(NDiscDNSSL)) + strlen(*i) + 1);
 454                 if (!s) {
 455                         log_oom();
 456                         return;
 457                 }
 458
 459                 strcpy(NDISC_DNSSL_DOMAIN(s), *i);
 460
 461                 if (lifetime == 0) {
 462                         (void) set_remove(link->ndisc_dnssl, s);
 463                         link_dirty(link);
 464                         continue;
 465                 }
 466
 467                 x = set_get(link->ndisc_dnssl, s);
 468                 if (x) {
 469                         x->valid_until = time_now + lifetime * USEC_PER_SEC;
 470                         continue;
 471                 }
 472
 473                 ndisc_vacuum(link);
 474
 475                 if (set_size(link->ndisc_dnssl) >= NDISC_DNSSL_MAX) {
 476                         log_link_warning(link, "Too many DNSSL records per link, ignoring.");
 477                         continue;
 478                 }
 479
 480                 r = set_ensure_allocated(&link->ndisc_dnssl, &ndisc_dnssl_hash_ops);
 481                 if (r < 0) {
 482                         log_oom();
 483                         return;
 484                 }
 485
 486                 s->valid_until = time_now + lifetime * USEC_PER_SEC;
 487
 488                 r = set_put(link->ndisc_dnssl, s);
 489                 if (r < 0) {
 490                         log_oom();
 491                         return;
 492                 }
 493
 494                 s = NULL;
 495                 assert(r > 0);
 496                 link_dirty(link);
 497         }
 498 }
 499
 500 static int ndisc_router_process_options(Link *link, sd_ndisc_router *rt) {
 501         int r;
 502
 503         assert(link);
 504         assert(rt);
 505
 506         r = sd_ndisc_router_option_rewind(rt);
 507         for (;;) {
 508                 uint8_t type;
 509
 510                 if (r < 0)
 511                         return log_link_warning_errno(link, r, "Failed to iterate through options: %m");
 512                 if (r == 0) /* EOF */
 513                         break;
 514
 515                 r = sd_ndisc_router_option_get_type(rt, &type);
 516                 if (r < 0)
 517                         return log_link_warning_errno(link, r, "Failed to get RA option type: %m");
 518
 519                 switch (type) {
 520
 521                 case SD_NDISC_OPTION_PREFIX_INFORMATION: {
 522                         uint8_t flags;
 523
 524                         r = sd_ndisc_router_prefix_get_flags(rt, &flags);
 525                         if (r < 0)
 526                                 return log_link_warning_errno(link, r, "Failed to get RA prefix flags: %m");
 527
 528                         if (link->network->ipv6_accept_ra_use_onlink_prefix &&
 529                             FLAGS_SET(flags, ND_OPT_PI_FLAG_ONLINK))
 530                                 (void) ndisc_router_process_onlink_prefix(link, rt);
 531
 532                         if (link->network->ipv6_accept_ra_use_autonomous_prefix &&
 533                             FLAGS_SET(flags, ND_OPT_PI_FLAG_AUTO))
 534                                 (void) ndisc_router_process_autonomous_prefix(link, rt);
 535
 536                         break;
 537                 }
 538
 539                 case SD_NDISC_OPTION_ROUTE_INFORMATION:
 540                         (void) ndisc_router_process_route(link, rt);
 541                         break;
 542
 543                 case SD_NDISC_OPTION_RDNSS:
 544                         if (link->network->ipv6_accept_ra_use_dns)
 545                                 (void) ndisc_router_process_rdnss(link, rt);
 546                         break;
 547
 548                 case SD_NDISC_OPTION_DNSSL:
 549                         if (link->network->ipv6_accept_ra_use_dns)
 550                                 (void) ndisc_router_process_dnssl(link, rt);
 551                         break;
 552                 }
 553
 554                 r = sd_ndisc_router_option_next(rt);
 555         }
 556
 557         return 0;
 558 }
 559
 560 static int ndisc_router_handler(Link *link, sd_ndisc_router *rt) {
 561         uint64_t flags;
 562         int r;
 563
 564         assert(link);
 565         assert(link->network);
 566         assert(link->manager);
 567         assert(rt);
 568
 569         r = sd_ndisc_router_get_flags(rt, &flags);
 570         if (r < 0)
 571                 return log_link_warning_errno(link, r, "Failed to get RA flags: %m");
 572
 573         if (flags & (ND_RA_FLAG_MANAGED | ND_RA_FLAG_OTHER)) {
 574                 /* (re)start DHCPv6 client in stateful or stateless mode according to RA flags */
 575                 r = dhcp6_request_address(link, !(flags & ND_RA_FLAG_MANAGED));
 576                 if (r < 0 && r != -EBUSY)
 577                         log_link_warning_errno(link, r, "Could not acquire DHCPv6 lease on NDisc request: %m");
 578                 else {
 579                         log_link_debug(link, "Acquiring DHCPv6 lease on NDisc request");
 580                         r = 0;
 581                 }
 582         }
 583
 584         (void) ndisc_router_process_default(link, rt);
 585         (void) ndisc_router_process_options(link, rt);
 586
 587         return r;
 588 }
 589
 590 static void ndisc_handler(sd_ndisc *nd, sd_ndisc_event event, sd_ndisc_router *rt, void *userdata) {
 591         Link *link = userdata;
 592
 593         assert(link);
 594
 595         if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER))
 596                 return;
 597
 598         switch (event) {
 599
 600         case SD_NDISC_EVENT_ROUTER:
 601                 (void) ndisc_router_handler(link, rt);
 602                 break;
 603
 604         case SD_NDISC_EVENT_TIMEOUT:
 605                 link->ndisc_configured = true;
 606                 link_check_ready(link);
 607
 608                 break;
 609         default:
 610                 log_link_warning(link, "IPv6 Neighbor Discovery unknown event: %d", event);
 611         }
 612 }
 613
 614 int ndisc_configure(Link *link) {
 615         int r;
 616
 617         assert(link);
 618
 619         r = sd_ndisc_new(&link->ndisc);
 620         if (r < 0)
 621                 return r;
 622
 623         r = sd_ndisc_attach_event(link->ndisc, NULL, 0);
 624         if (r < 0)
 625                 return r;
 626
 627         r = sd_ndisc_set_mac(link->ndisc, &link->mac);
 628         if (r < 0)
 629                 return r;
 630
 631         r = sd_ndisc_set_ifindex(link->ndisc, link->ifindex);
 632         if (r < 0)
 633                 return r;
 634
 635         r = sd_ndisc_set_callback(link->ndisc, ndisc_handler, link);
 636         if (r < 0)
 637                 return r;
 638
 639         return 0;
 640 }
 641
 642 void ndisc_vacuum(Link *link) {
 643         NDiscRDNSS *r;
 644         NDiscDNSSL *d;
 645         Iterator i;
 646         usec_t time_now;
 647
 648         assert(link);
 649
 650         /* Removes all RDNSS and DNSSL entries whose validity time has passed */
 651
 652         time_now = now(clock_boottime_or_monotonic());
 653
 654         SET_FOREACH(r, link->ndisc_rdnss, i)
 655                 if (r->valid_until < time_now) {
 656                         free(set_remove(link->ndisc_rdnss, r));
 657                         link_dirty(link);
 658                 }
 659
 660         SET_FOREACH(d, link->ndisc_dnssl, i)
 661                 if (d->valid_until < time_now) {
 662                         free(set_remove(link->ndisc_dnssl, d));
 663                         link_dirty(link);
 664                 }
 665 }
 666
 667 void ndisc_flush(Link *link) {
 668         assert(link);
 669
 670         /* Removes all RDNSS and DNSSL entries, without exception */
 671
 672         link->ndisc_rdnss = set_free_free(link->ndisc_rdnss);
 673         link->ndisc_dnssl = set_free_free(link->ndisc_dnssl);
 674 }